TY - JOUR. T1 - Structural Phase Transitions at Clean and Metal-Covered Si(111) Surfaces Investigated by Rheed Spot Analysis. AU - Hasegawa, Shuji. AU - Nagai, Yasuyoshi. AU - Oonishi, Toshio. AU - Kobayashi, Nobuhiko. AU - Miyake, Takashi. AU - Murakami, Shuuichi. AU - Ishii, Yuuji. AU - Hanawa, Daiki. AU - Ino, Shozo. PY - 1995/3/1. Y1 - 1995/3/1. N2 - Structural phase transitions between various kinds of superlattice structures formed on a Si(111) surface have been investigated by spot analysis of reflection high-energy electron diffraction (RHEED). Reversible transitions induced by temperature changes and irreversible ones induced by metal depositions were observed. Detailed discussions on the dynamics of the phase transitions are made by quantitative analyses of integrated spot intensity and profile. For a phase transition of 7x7âŸ1x1 structures on a clean Si(111) surface, a hysteresis with temperature difference of 5° C between in heating and cooling processes was found in the spot ...
Paracetamol is a sparingly soluble bitter tasting drug. It is widely used as an analgesic and antipyretic. Complexation of drug with different cyclodextrins (?, ? and HP-?-CD) was attempted to improve solubility of Paracetamol. During the drug excipient interaction studies, ?, ? cyclodextrins elicited analytical interference and showed considerable absorbance at ?max (243.5 nm) of Paracetamol while the ones constituting of hydroxypropyl-beta-cyclodextrin (HP-?-CD) did not show any such interference. Therefore, the present study is concentrated on exploring HP-?-CD as complexing agent. Phase solubility studies showed that complexation of Paracetamol/HP-?-CD at molar ratio 1:1 and showed AL type solubility curve. Complexation was done by various methods like physical mixing, kneading and freeze drying and resulting drug complexes were characterized by Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FTIR). The thermograms obtained showed an endothermic peak for
A preliminary thermo gravimetric measurement was performed over a temperature range from room temperature to 240 °C. Beginning at room temperature the mass loss rate increased steadily, reaching a maximum at 94°C and exhibiting a small shoulder in the DTG curve at 107°C,. Mass loss was complete at 115°C, taking into account the initial mass loss from purging (21.7%) before the start of the measurement. There was no residue left. The DSC measurements were performed twice. To determine a possible boiling point more precisely a crucible lid with a hole of 50 Om diameter was used in the measurements. The small hole causes the generation of a defined atmosphere at constant pressure inside the crucible and allows measurements at near equilibrium conditions, thus preventing evaporation of the test material before reaching the boiling point. The sample was quenched down to -150°C. Upon heating the enthalpy curves show a small exothermic peak at -135°C (crystallisation) and a small endothermic peak ...
During the heating phase an endothermic effect was observed in the temperature range of 50 - 70 °C, which can be assigned to the melting of the test item. The test item showed a second endothermic signal in the temperature range of approx. 160 - 270 °C that can be assigned to the boiling of the test item. For the correction of the boiling temperature to standard pressure the test item was assigned to chemical group 2 (e.g. Hydrocarbons). A correction value φ = 5.05 was used for the temperature of 240 - 250 °C. The lowest measured onset temperature is corrected to the standard pressure to be 243.23 °C and the highest onset temperature to be 243.53 °C. As the corrected onset temperatures in both tests deviate less than 0.5 K from their mean value of 243.38 °C, the test item has a boiling point of 243.4 °C. No further thermal effects were observed up to the maximum test temperature of 500 °C. Final Results The test item has a boiling point of 243.4 °C corrected to normal atmospheric ...
They carried out DSC studies on the cyclopropane and on the bromodiene. The first step involves dibromocarbene addition to the but-2-ene and noted that the cyclopropane decomposes at an onset temperature of 145°C releasing 360 J/g and the diene at 226°C delivering 500 J/g. Both non-trivial amounts of energy. According to their SOPs a 100°C difference between onset temperature and reaction temperature must be observed for a decent safety margin to be maintained. To get around this problem two thing were done a) the dibromocyclopropane was isolated and b) the conversion to the bromodiene was carried out in a continuous flow reactor. A further complication is that the dibromocyclopropane is sensitive to basic conditions and careful work-up conditions had to be chosen to avoid high pH. Using t-BuOK/CHBr3 in heptanes the reaction was addition controlled at 0°C and gave a 98% yield of the diene precursor.. It was determined that the bromodiene was optimally synthesised by using a reaction ...
TY - JOUR AU - Balanč, Bojana AU - Ota, Ajda AU - Đorđević, Verica AU - Sentjurc, Marjeta AU - Nedović, Viktor AU - Bugarski, Branko AU - Poklar-Ulrih, Nataša PY - 2015 UR - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3075 AB - The influence of resveratrol encapsulated into liposomes (prepared with a commercial lipid mixture of phospholipids, phospolipon 90NG, using the thin film and proliposome methods) on the structural properties of the liposome membrane was investigated by electron paramagnetic resonance (EPR) spectroscopy, fluorescence spectroscopy, and differential scanning calorimetry. Two fluorophores and two spin probes were used to monitor the characteristics of membranes made from a commercial mixture of phosphatidylcholine. Resveratrol was positioned rather in the inner part of the liposome membranes causing reduction in membrane fluidity. Moreover, resveratrol induced a concentration-dependent decrease in the gel-to-liquid crystalline phase transition temperature (from 41.3 ...
Abstract: We use holographic techniques to study SU(Nc) super Yang-Mills theory coupled to Nf ,, Nc flavours of fundamental matter at finite temperature and baryon density. We focus on four dimensions, for which the dual description consists of Nf D7-branes in the background of Nc black D3-branes, but our results apply in other dimensions as well. A non-zero chemical potential mu or baryon number density n is introduced via a nonvanishing worldvolume gauge field on the D7-branes. Ref. [1] identified a first order phase transition at zero density associated with `melting of the mesons. This extends to a line of phase transitions for small n, which terminates at a critical point at finite n. Investigation of the D7-branes thermodynamics reveals that (d mu / dn)_T ,0 in a small region of the phase diagram, indicating an instability. We comment on a possible new phase which may appear in this region ...
Polyester-like thermoplastic products obtained as a result of the reaction between lignins and terephthaloyl chrolide were examined. Steam exploded lignin (L) and sodium lignosulphonates (LS) were modified with terephthaloyl chloride. Some molecular and thermal properties of lignin modificates were determined. As a result of TG analysis it can be stated that modified product have higher temperature of a maximum weight loss than initial lignins. In thermograms of the initial lignins only endothermic peaks at 124 and 121°C for LS and 111°C for L can be observed. In case of modified LS the additional enothermic peak at 401°C is noticed. It is probably caused by thermal decomposition of the products. For modified product of LS an exothermic peaks at 313°C is observed. Molecular properties of lignins and products of their modification were evaluated using gel permeation chromatography (GPC). Due to GPC application a comparison of molecular weight distribution both for lignins and for products of ...
Polyester-like thermoplastic products obtained as a result of the reaction between lignins and terephthaloyl chrolide were examined. Steam exploded lignin (L) and sodium lignosulphonates (LS) were modified with terephthaloyl chloride. Some molecular and thermal properties of lignin modificates were determined. As a result of TG analysis it can be stated that modified product have higher temperature of a maximum weight loss than initial lignins. In thermograms of the initial lignins only endothermic peaks at 124 and 121°C for LS and 111°C for L can be observed. In case of modified LS the additional enothermic peak at 401°C is noticed. It is probably caused by thermal decomposition of the products. For modified product of LS an exothermic peaks at 313°C is observed. Molecular properties of lignins and products of their modification were evaluated using gel permeation chromatography (GPC). Due to GPC application a comparison of molecular weight distribution both for lignins and for products of ...
High sensitivity differential scanning calorimetry (d.s.c.) and uv-visible spectrophotometry have been used to study the thermal unfolding of alpha-chymotrypsin in presence of calcium chloride at pH = 2.8, 3.4, 5.0, 7.0, and 8.2. Quantitative thermodynamic parameters accompanying the thermal transitions have been evaluated. In the absence of calcium ions, the thermal denaturation of a-chymotrypsin is a reversible process giving a ratio of the vant Hoff to calorimetric enthalpy of 0.92 at pH = 2.8. At pH values higher than 5.0, the thermal denaturations in the absence of calcium chloride were observed to be completely irreversible. In the presence of calcium chloride, alpha-chymotrypsin undergoes irreversible thermal denaturation and its thermal transitions are found to be scan-rate dependent fitting to the model N-2 --, I, yielding an average activation energy of (419 +/- 16) kJ (.) mol(-1) using different approaches at pH = 2.8. It is also observed that at pH 2.8 and 3.4, calcium reduces the ...
However, above 50 K the thermal expansivity of the cell volume for the heating sequence is markedly lower when compared with the cooling sequence. Similar behaviour is shown by the a, c and b lattice constants, whereas the b lattice constant exhibits a less negative expansion. The thermal treatment of the sample offers a likely explanation for this observation. The sample was initially quenched at 100 K and then cooled to 5 K. Data recorded on warming this sample were composed entirely of the phase II structure until the transition onset around 210 K. In contrast, the phase II sample for the cooling sequence was transformed via the phase I structure and lattice parameters for both phases could be refined down to 167 K. Very weak peaks corresponding to the phase I structure were in fact observed down to 100 K. The intergrowth of phase II and phase I structures and sluggish nature of the transition would both affect the observed thermal expansivity of phase II in the cooling sequence. ...
For this endpoint one study is available. The explosive properties of the test item were assessed according to Regulation EC No. 440/2008 Method A.14. Explosive Properties and OECD Test Guideline 113 (1981): Thermal Stability (DSC measurement). In the DSC-measurement the energy of the exothermic decomposition of the test item was , -500 J/g. The onset temperature for the exothermic decomposition was 350°C. Therefore, further tests for explosive properties had not to be performed. It is concluded that the test item has no explosive properties. ...
This article reports the temperature dependence of the structural and photoelectrical properties of C60 thin films with varying crystal structure and oxygen content near the orientational disorder/order phase transition at about 260 K. X-ray diffraction data demonstrate that highly crystalline oxygen-free C60 films undergo the first-order phase transition at 252 K with a lattice parameter discontinuity Δa/a of 0.22%; no discontinuity was observed in C60 films with coexisting amorphous and nanocrystalline phases. A strong effect of the phase transition on the dark- and photoconductivity in those films is presented: In highly crystalline C60 films both dark- and photoconductivity increase as the temperature is lowered through the transition region. However, opposite temperature changes of the conductivity are observed in nanocrystalline/amorphous C60 films. In situ exposure of samples to oxygen gas suppresses any critical behavior. The experimental results are interpreted in terms of ...
Polymorphic transitions of α-phenylcinnamic acid stereoisomers crystallized from various solvents (CHCl3, ethanol, diethyl ether), precipitated with different acids (acetic acid or HCl) or sublimed have been studied by differential scanning calorimetry (DSC). Measurements were also supplemented by powder X-ray diffractometry (XRD). Polymorphic transitions were not found for any of the E isomer samples irrespective of the method of treatment. However, in heating-cooling cycles reversible transitions could be detected for the Z isomer. On heating an exothermic peak was registered on samples sublimed, crystallized from ethanol or diethyl ether before melting, while samples precipitated by HCl or crystallized from chloroform exhibited more complex transitions. Here, endothermic effects were also observed. Enthalpy values for transformations (either for melting or polymorphic and other transitions) are also given. ...
Most polymeric materials are based on non-renewable fossil resources, respectively petrochemicals. As regenerable resources carbohydrates have attracted great attention in the last decade for production of polymeric materials. The biodegradable polymers are indispensable in the modern society and their importance is continuously growing. In this paper we report the thermal properties of a new class of biodegradable copolymers derived from monosaccharides. The glycomonomers 3-O-acryloyl-1,2:5,6-di-O-isopropylidene-α-D-glucofuranose, and 1-O-acryloyl-2,3:5,6-di-O-isopropylidene-α-D-mannofuranose, were co-polymerized with 2-hydroxypropyl methacrylate, using benzoyl and lauroyl peroxide as initiators. The copolymerization process between glycomonomers and 2-hydroxypropyl methacrylate was studied using differential scanning calorimetry analysis (DSC). The storage and loss modulus were evaluated using DMA technigue (dynamic mechanical analysis), while the thermal stability of the obtained products ...
TY - JOUR. T1 - Fabrication and characterization of a solid polymeric electrolyte of PAN-TiO2-LiClO4 AU - Abd Rahman, Mohd Yusri. AU - Ahmad, Azizan. AU - Ismail, L. H C. AU - Mat Salleh, Muhamad. PY - 2010/2/15. Y1 - 2010/2/15. N2 - The ionic conductivity of PAN-TiO2-LiClO4 as a function of TiO2 concentration and temperature has been reported. The electrolyte samples were prepared by solution casting technique. Their conductivity was measured using the impedance spectroscopy technique. The highest room temperature conductivity of 1.8 × 10-4 S cm-1 was obtained at 7.5 wt % of TiO2 filler. It was observed that the relationship between temperature and conductivity were linear, fitting well in Arrhenius and not in Vogel-Tamman-Fulcher equation. The pre-exponential factor, σ0 and Ea are 1.8 × 10-4 S cm-1 and 0.15 eV, respectively. The conductivity data have been supported by differential scanning calorimeter (DSC) analysis. DSC analysis showed that there was a significant change in glass ...
Dortmund Data bank - Thermophysical Properties | Benzene, CAS Number: 71-43-2 | 1-Propanol, CAS Number: 71-23-8 | SpringerMaterials 2014
An endotherm (from Greek ἔνδον endon within and θέρμη thermē heat) is an organism that maintains its body at a metabolically favorable temperature, largely by the use of heat set free by its internal bodily functions instead of relying almost purely on ambient heat. Such internally generated heat is mainly an incidental product of the animals routine metabolism, but under conditions of excessive cold or low activity an endotherm might apply special mechanisms adapted specifically to heat production. Examples include special-function muscular exertion such as shivering, and uncoupled oxidative metabolism such as within brown adipose tissue. Only birds and mammals are extant universally endothermic groups of animals. Certain lamnid sharks, tuna and billfishes are also endothermic. In common parlance, endotherms are characterized as warm-blooded. The opposite of endothermy is ectothermy, although in general, there is no absolute or clear separation between the nature of ...
A paper structure having at least three regions is disclosed. The paper structure has a first region, a patterned second region, and a third transition region connecting the first and second regions. The first and second regions are disposed at different elevations, and can each have a thickness less than a thickness of the transition region. An apparatus and process for making such a paper structure are also disclosed.
This is also reflected in the solubility versus temperature phase diagram (Fig. 3A), which shows a region of concentrations where the HB oligomer is unstable (below the dashed purple line and above the black solubility line) and a region where the oligomer is metastable (above the dashed purple line). Similar arguments can be made for the other metastable phases, such as the two, three, and four β-sheet fibril phases. We emphasize that we did not calculate free energies as we were able to calculate the solubilities directly; the discussion here is mainly presented for pedagogical purposes.. Knowledge of the thermodynamically stable and metastable phases in the phase diagram allows us to determine the conditions under which the oligomer or fibril can form. A previous discontinuous molecular dynamics (DMD) study of Aβ16-22 kinetic aggregation by Cheon et al. (6) found that at 20 mM and T* = 0.2, corresponding to 342 K, a system of peptides in a random configuration first forms a fibril nucleus, ...
FT-IR and 2D correlation spectroscopy were employed to study the microstructural changes ocurring during phase transitions of a liquid crystal poly(amidoamine) codendrimer (PAMAM (L1)16(L2)16) generation 3, functionalized on the terminal groups by one-chain promesogenic calamitic units (4-(4-decyloxybenzoyloxy)salicylaldehyde (L1)) and two-chain promesogenic calamitic units (4-(3,4-didecyloxybenzoyloxy)salicylaldehyde (L2)). Spectral modifications associated with molecular conformation rearangements allowing for molecular shape change on going from a liquid−crystalline organization to another were found. The transition temperatures were calculated, and they are in good agreement with the DSC data. Spectral analysis gives evidence of the LC phase transitions and to an additional transition associated with the existence of conformers. Various types of hydrogen bonding have been established ...
When an object absorbs light, the light energy is transferred to heat energy. The amount of heat that is absorbed depends on whether the color of the object reflects, absorbs or transmits. Simple science experiments are possible to determine how different colors respond to light and how much heat each color absorbs.
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Thermogram of a cat. The different colours represent different temperatures. The lightest colours are the hottest temperatures, while the darker colours represent cooler temperatures. Thermography uses special cameras that can detect light in the far-infrared range of the electromagnetic spectrum (900-14,000 nanometers or 0.9-14 µm) to create an image that represents an objects temperature. - Stock Image Z934/0730
Industrially textured PLA multifilaments were heat set under different conditions at 110 ºC for 1 min and subjected to one cycle of deformation up to 20%. Thermal transitions of the original textured, heat set and cyclic strained filaments were measured using differential scanning calorimetry from 25 to 250 ºC. Cyclic deformation induces an endo-exo transition at peak temperatures between 55 - 60 ºC that is not observed in the original textured and heat set multifilaments. There is another endo-exo transition with peak temperatures between 67 and 72 ºC in all filaments, the intensity of which varies according to texturing conditions, heat setting and cycle strain. Texturing conditions, heat setting and cyclic strain play a role in thermal transitions, the strain at breaking and elastic properties of the filaments. The crystallinity and magnitude of the endo-exo thermal events detected by DSC are related to the strain at breaking and elasticity of polylactide textured ...
You may also wish to search for items by Massalska-Arodz. 7 matching references were found. Rachwalska, M.; Massalska-Arodz, M.; Moscicki, J.K.; Jaich, A., Calorimetric study of NPOB, Mol. Cryst. Liq. Cryst., 1982, 80, 157-164. [all data] Bamezai, R.K.; Godlewska, M.; Massalska-arodz, M.; Sciesinski, J.; Witko, W., The adiabatic calorimetry study of the polymorphism of solid 4,4-di-n-butyloxyazoxybenzene, Phase Transitions, 1990, 27(2-3), 113-119. [all data] Mayer, J.; Witko, W.; Massalska-Arodz, M.; Williams, G.; Dabrowski, R., Polymorphism of right handed (S) 4-(2-Methylbutyl) 4´-Cyanobiphenyl, Phase Transitions, 1999, 69, 2, 199-213, https://doi.org/10.1080/01411599908208019 . [all data] Sciesinski, J.; Sciesinska, E.; Massalska, E.; Massalska-Arodz, M.; Wasiutynski, T.; Zielinski, P.M.; Witko, W., Polymorphism of righthanded octyloxycyanobiphenyl, IEEE Trans. Dielect. Electr. Insul., 2001, 8, 3, 522-526, https://doi.org/10.1109/94.933377 . [all data] Massalska-Arodz, M., Specific-heat ...
The outermost membrane of gram-negative bacteria is a lipopolysaccharide (LPS) rich bilayer assembly that acts as the first line of defense for bacterial cells in adverse physical and chemical environments. Besides the LPS, the outer membrane has radially extending O-antigen polysaccharide chains and β-barrel membrane proteins that make the bacterial membrane physiologically unique compared to the phospholipid cell membranes. To study the molecular complexity and dynamics of the LPS rich membrane, we have developed coarse grained parameter set for the outer membrane compatible with the Martini force field. The coarse grained model was benchmarked against available experimental and atomistic simulations data for properties such as membrane thickness, density profiles of the residues, area per lipid, gel to liquid-crystalline phase transition temperatures, order parameters, and radial distribution functions. More than 17 membrane compositions were studied with a combined simulation time of over 100
A chemical registry was created from a literature review and included characteristics relevant to XL such as molecular weight, carcinogenicity/mutagenicity, toxicity, hydrophobicity, and commercial availability. From this registry, compounds were then selected for efficacy screening using an ex vivo rabbit corneal cross-linking simulation set up. XL solution was administered via a corneal reservoir for 30 min in 0.1M NaHCO3 at either pH 7.4 or 8.5. The epithelium was left intact and 0.5% proparacaine was applied prior to XL. The control contralateral eye was treated identically with vehicle. Effectiveness of XL was based on shifts in thermal denaturation temperature (Tm) as measured by differential scanning calorimetry (Perkin-Elmer DSC 6000). Favorable DSC results were validated using biomechanical inflation tests with digital image correlation (DIC) as previously described by Myers et al.. ...
Gadolinium silicide (Gd5Si4) nanoparticles (NPs) exhibit different properties compared to their parent bulk materials due to finite size, shape, and surface effects. NPs were prepared by high energy ball-milling of the as-cast Gd5Si4ingot and size separated into eight fractions using time sensitive sedimentation in an applied dc magnetic field with average particle sizes ranging from 700 nm to 82 nm. The largest Gd5Si4 NPs order ferromagnetically at 316 K. A second anomaly observed at 110 K can be ascribed to a Gd5Si3 impurity. As the particle sizes decrease, the volume fraction of Gd5Si3 phase increases at the expense of the Gd5Si4 phase, and the ferromagnetic transition temperature of Gd5Si4 is reduced from 316 K to 310 K, while the ordering of the minor phase is independent of the particle size, remaining at 110 K.
You may also wish to search for items by Hu. 54 matching references were found. Huang, W.; Zhou, Y.; Tan, F.; Xu, G.; Hu, Y.; Hu, H., 8-Hydroxymethylcoumarin derivatives. II. DSC study of phase transitions, Huaxue Wuli Xuebao, 1992, 5, 3, 178. [all data] Zhang, Q.; Qiu, Z.; Luo, Z.; Hu, Y., Vapor-liquid equilibria of trioxane-water and trioxane-1,2- dichloroethane system, Huadong Ligong Daxue Xuebao, 1996, 22, 7-12. [all data] Zhang, G.; Ying, X.; Ye, R.; Hu, Y., Vapor-liquid equilibria for solvent-oil, solvent-wax and continuous thermodynamic study, Huadong Ligong Daxue Xuebao, 1996, 22, 486-494. [all data] Zhang, G.; Ye, R.; Huang, S.; Ying, X.; Hu, Y., Vapor-liquid equilibria for furfural-oil, N-methyl-2-pyrrolidone-oil and approach to pseudo-component method, Huadong Ligong Daxue Xuebao, 1995, 21, 631-9. [all data] Ye, Q.; Zhong, C.; Hu, Y., Prediction of vapor-liquid equilibria of binary and ternary systems by UNIFAC combined with PRSV equation of state, Huaxue Gongcheng (Xian, Peoples ...
1B5U: CONTRIBUTION OF HYDROGEN BONDS TO THE CONFORMATIONAL STABILITY OF HUMAN LYSOZYME: CALORIMETRY AND X-RAY ANALYSIS OF SIX SER-|ALA MUTANT
The CMS hadronic calorimeter (HCAL) employs a plastic-scintillator-based endcap detector. The CMS HCAL Phase 1 upgrade involves installing silicon photomultipliers (SiPM) to measure light from scintillators in the detector. The SiPM signals are digitized by custom readout cards, called QIE cards, using the charge integration and encoder version 11 (QIE11) chip. The QIE cards for the HCAL endcap (HE) were tested and calibrated at FNAL. Then at CERN the QIE cards completed high radiation tests in the CHARM facility and muon/pion energy measurements in testbeam. Finally, the HE readout electronics were installed in CMS in 2018. The HCAL endcaps were calibrated using two Co-60 radiation sources. During physics data-taking in 2018, the HCAL online software (HCOS) configures and monitors the readout electronics to ensure data quality. This talk will summarize the testing, installation and commissioning of the HE Phase 1 upgrade readout system ...
LISA may be able to detect the gravitational waves from a first order phase transition at the electroweak scale. We present results from a large campaign of simulations studying a model of such phase transitions, and determine the shape of the power spectrum with unparalleled accuracy. We make concrete predictions of the detectability of sound waves from such a scenario, and note that an accurate measurement could place constraints on the underlying phase transition parameters.. ...
Journal of Shahid Sadoughi University of Medical Sciences ماهنامه علمی پژوهشی دانشگاه علوم پزشکی و خدمات بهداشتی درمانی شهید صدوقی یزد
I did an experiment using a calorimeter to determine the energy produced when certain salts are mixed with water. How do you calculate the energy absorbed when mixing salts with water that produce an endothermic reaction, make thing the water cold, but with regards to calorimetry? I dont know how to get the energy but I know how to get the molar enthalpy, but I am still confused, if I calculate just for energy using q=mct I feel like Im not taking into consideration everything regarding
The material contains several polymers and additives. It is important that each component has a similar melting point. To find the right formulation we use the DSC analysis and the Kofler hot stage ...
NFPA chapter 15 page 11 to page 15 DESIGN and INSTALLATION clause 4-4.3.2 VESSELS delineates;. (a) These rules for exposure protection contemplate emergency relieving capacity for vessles, based upon a maximum allowable heat input of 6,000 BTU per hour per sg ft (18,930 W/sq m) of exposed surface area. The density shall be increased to limit the heat absorption to a safe level in the event required emergency relieving capacity is not provided.. (b) Water shall be applied to VERTICAL or INCLINED vessel surfaces at a Net Rate of Not less that 0.25 Gallon per minutes per sq ft (10.17 Liter per minute per sq meter) of exposed un-insulated surface ...
Abstract: The nature of axion cosmology is usually said to depend on whether the Peccei-Quinn (PQ) symmetry breaks before or after inflation. The PQ symmetry itself is believed to be an accident, so there is not necessarily a symmetry during inflation at all. We explore these issues in some simple models, which provide examples of symmetry breaking before and after inflation, or in which there is no symmetry during inflation and no phase transition at all. One effect of these observations is to relax the constraints from isocurvature fluctuations due to the axion during inflation. We also observe new possibilities for evading the constraints due to cosmic strings and domain walls, but they seem less generic ...
Extramarks provides online study material for ICSE class 10 Calorimetry chapter. Practice physics icse board sample papers to score good marks in exams.
Dense protein clusters are known to play an important role in nucleation of protein crystals from dilute solutions. While these have generally been thought to be formed from a metastable phase, the observation of similar, if not identical, clusters above the critical point for the dilute-solution/strong-solution phase transition has thrown this into doubt. Furthermore, the observed clusters are stable for relatively long times. Because protein aggregation plays a central role in some pathologies, understanding the nature of such clusters is an important problem. One mechanism for the stabilization of such structures was proposed by Pan, Vekilov and Lubchenko and was investigated using a dynamical density functional theory model which confirmed the viability of the model. Here, we revisit that model and incorporate additional physics in the form of state-dependent reaction rates. We show by a combination of numerical results and general arguments that the state-dependent rates disrupt the ...
Calorimetry deals with the energetics of atoms, molecules, and phases and can be used to gather experimental details about one of the two roots of our knowledge about matter. The other root is structural science. Both are understood from the microscopic to the macroscopic scale, but the effort to learn about calorimetry has lagged behind structural science. Although equilibrium thermodynamics is well known, one has learned in the past little about metastable and unstable states. Similarly, Dalton made early progress to describe phases as aggregates of molecules. The existence of macromolecules that consist of as many atoms as are needed to establish a phase have led, however, to confusion between colloids (collections of microphases) and macromolecules which may participate in several micro- or nanophases. This fact that macromolecules can be as large or larger than phases was first established by Staudinger as late as 1920. Both fields, calorimetry and macromolecular science, found many ...
Abstract: We find an unexpected tetragonal-to-monoclinic-to-rhombohedral-to-cubic phase transition sequence induced by pressure, and a morphotropic phase boundary in a pure compound using first-principles calculations. Huge dielectric and piezoelectric coupling constants occur in the transition regions, comparable to those observed in the new complex single-crystal solid-solution piezoelectrics such as Pb(Mg$_{1/3}$Nb$_{2/3}$)O$_{3}$-PbTiO$_{3}$, which are expected to revolutionize electromechanical applications. Our results show that morphotropic phase boundaries and giant piezoelectric effects do not require intrinsic disorder, and open the possibility of studying this effect in simple systems ...
1B5X: Contribution of hydrogen bonds to the conformational stability of human lysozyme: calorimetry and X-ray analysis of six Ser --> Ala mutants.
Brief Summary Report of MHE Project Phenomenology and Controllability of New Exothermic Reaction between Metal and Hydrogen (Quote) https://www.researchgate.net/p…etween_Metal_and_Hydrogen
A new homologous series (ten compounds) of 2-hydroxy azo compounds SRn (where n:1-10) were synthesized. Their structures were elucidated using spectroscopic techniques such as IR (Infrared), 1H-NMR as well as elemental analysis. Mesomorphic properties and phase transitions were studied using polarized hot stage optical microscopy and differential scanning calorimetry (DSC), and are discussed as a function of the number of carbon atoms in the thioalkyl chain. It has been found that all compounds in the series are pure nematogens.
The thermal phase transition behavior of maize starch in water:ionic liquid (IL) mixtures was investigated. With decreasing water:IL molar ratio to 10:1, the endothermic transition shifted to higher temperatures, and then to lower temperatures at 5:1 water:IL ratio. At 2:1 water:IL ratio, an exothermic transition occurred at a lower temperature than gelatinization temperature of starch in pure water. At the same water:IL ratios (35:1 to 5:1), the endothermic transition temperatures of starch increased with decreasing alkyl chain length of the cation, whereas an opposite trend was found for the exothermic transition at 2:1 water:IL ratio. Rheological, 1H NMR and FTIR analyses of water:IL mixtures showed that with decreasing water:IL ratio, the viscosity of water:IL mixture and the interactions between cation and anion increased, whereas the interactions between IL and water increased and then decreased. The endothermic transition of starch in water:IL mixtures of 35:1 to 5:1 was affected by the ...
The effects of the antipsychotic drug, chlorpromazine hydrochloride (CPZ) on the phase behavior of hydrated dipalmitoylphosphatidylcholine (DPPC) have been investigated by fluorescence spectroscopy and differential scanning calorimetry. Incorporation of the amphiphilic drug into the bilayer began to dramatically affect its fluidity at 2 mol% CPZ. With increasing CPZ concentration, the pre- and main transition temperatures of DPPC decrease. These thermal shifts demonstrate that interactions of the tricyclic phenothiazine ring on CPZ with the lipid headgroups disorder the acyl chains of DPPC such that it favors the liquid crystalline phase over the gel phase. Fluorescence anisotropy results confirm that the acyl chain regions near the phenothiazine ring become more fluid with higher amounts of CPZ. The sub- and pre-transition peaks disappear in the presence of 5 mol% CPZ, indicating a direct transition from planar gel to the liquid crystalline phase upon destabilization of the subgel and rippled ...
The binding of insulin to the G-quadruplexes formed by the consensus sequence of the insulin-linked polymorphic region (ILPR) was investigated with differential scanning calorimetry (DSC) and isothermal titration calorimetry (ITC). The thermal denaturation temperature of insulin was increased by almost 4 oC upon binding to ILPR G-quadruplex DNA as determined by DSC. The thermodynamic parameters (KD, H, G and S) of the insulin-G-quadruplex complex were further investigated by temperature-dependent ITC measurement over 10-37 °C. The binding of insulin to the ILPR consensus sequence displays micromolar affinity in phosphate buffer at pH 7.4, which and is mainly driven by entropic factors at below 25 °C but by enthalpic factors terms at above 30 °C. The interaction was also examined in several different buffers and results showed that observed H is dependent on the ionization enthalpy of the buffer used. This indicates proton release upon the binding of G-quadruplex DNA to insulin. ...
They carried out DSC studies on the cyclopropane and on the bromodiene. The first step involves dibromocarbene addition to the but-2-ene and noted that the cyclopropane decomposes at an onset temperature of 145°C releasing 360 J/g and the diene at 226°C delivering 500 J/g. Both non-trivial amounts of energy. According to their SOPs a 100°C difference between onset temperature and reaction temperature must be observed for a decent safety margin to be maintained. To get around this problem two thing were done a) the dibromocyclopropane was isolated and b) the conversion to the bromodiene was carried out in a continuous flow reactor. A further complication is that the dibromocyclopropane is sensitive to basic conditions and careful work-up conditions had to be chosen to avoid high pH. Using t-BuOK/CHBr3 in heptanes the reaction was addition controlled at 0°C and gave a 98% yield of the diene precursor.. It was determined that the bromodiene was optimally synthesised by using a reaction ...
The interactions of trimethoprim, sulphadiazine and sulphamethoxazole with natural (alpha-, beta-, gamma-) and amorphous (RAMEB) or crystalline (DIMEB) methylated beta-cyclodextrins were investigated both in aqueous solution (using phase-solubility analysis) and in the solid state (using DSC supported by X-ray analysis). In particular, DSC studies enabled determination of the relative degree of crystallinity of each drug in its physical and ground mixtures with the different cyclodextrins on the basis of the variation of its heat of fusion in comparison with that of the pure drug. In all cases, the host cavity size was a prevalent factor for the inclusion complexation in liquid state. On the contrary, it had a negligible effect on solid-state interactions in terms of drug amorphization. DIMEB and RAMEB exhibited similar performances in aqueous solution, showing that the presence of methyl-groups improved the complexing and solubilizing properties of beta-cyclodextrin. However, DSC studies ...
The determination of the boiling point temperature range of the test material Maleated rosin esters of glycerol was performed by Differential Scanning Calorimetry and in accordance with OECD Guideline 103. No boiling was observed until the test item reached 300°C. An insignificant endothermic peak corresponding to the glass transition temperature with its relaxation peak was observed. No decomposition was observed until 300°C (2 peaks were observed but considered insignificant). Based on the result of this study it can be concluded that the test item did not vaporise or decompose at -40°C up to 300°C. ...
Breath cancer analysis. Thermographic footage of a man breathing towards a dogs nose as part of a test for cancer. A thermogram shows variation in temperature on the surface of an object, measured by the long-wave infrared radiation it emits. The temperature scale is colour-coded from black (cold) through dark blue, light blue, green and yellow to red and white (hottest). This thermogram footage shows that exhaled air is warm, but cools quickly. Dogs have an extremely sensitive sense of smell, and can be trained to detect different types of chemicals, including those produced in the breath in some forms of cancer. - Stock Video Clip K004/5646
TY - JOUR. T1 - Ureaerature phase diagrams capture the thermodynamics of denatured state expansion that accompany protein unfolding. AU - Tischer, Alexander. AU - Auton, Matthew. PY - 2013/9. Y1 - 2013/9. N2 - We have analyzed the thermodynamic properties of the von Willebrand factor (VWF) A3 domain using urea-induced unfolding at variable temperature and thermal unfolding at variable urea concentrations to generate a phase diagram that quantitatively describes the equilibrium between native and denatured states. From this analysis, we were able to determine consistent thermodynamic parameters with various spectroscopic and calorimetric methods that define the urea-temperature parameter plane from cold denaturation to heat denaturation. Urea and thermal denaturation are experimentally reversible and independent of the thermal scan rate indicating that all transitions are at equilibrium and the vant Hoff and calorimetric enthalpies obtained from analysis of individual thermal transitions are ...
Stability and molecular size of the DNA double helical structure were studied on an aqueous solution of DNA after exposure to high power doses of continuous wave ultrasound at frequency of 20kHz. Thermal transition spectrophotometry (UV-melting), constant-field gel electrophoresis (CFGE), differential scanning calorimetry (DSC) and dielectric properties measurements were used to evaluate the ultrasound-induced changes in the DNA double helical structure. The thermal transition spectrophotometry (UV-melting) and differential scanning calorimetry (DSC) results showed that ultrasound power caused loss of DNA double helical structure and the DNA double strands melting temperature decreased as the ultrasound power increased, indicating a decrease in the stability of the double helical structure of DNA. The constant-field gel electrophoresis (CFGE) results showed that the molecular size of the DNA fragments decreased as the ultrasound power increased. The dielectric data in the frequency range from ...
Dilauroylglycerol arginine conjugates constitute a novel class of specific biocompatible surfactants, which can be considered analogues of partial glycerides and phospholipids. During their preparation, spontaneous intramolecular acyl-migration reactions are observed and both possible regioisomers are obtained: 1,2-dilauroyl-rac-glycero-3-(Nα-acetyl-l-arginine) (1212RAc) and 1,3-dilauroylglycero-2-(Nα-acetyl-l-arginine) (12RAc12). To study the influence of the presence of both regioisomers on the physicochemical properties, the phase behavior in the dry state of pure 1,2-dilauroyl-rac-glycero-3-(Nα-acetyl-l-arginine) and two mixtures of both regioisomers were studied by differential scanning calorimetry and small-angle X-ray diffraction complemented by polarized light microscopy. The experiments were performed for a sequence of heating, cooling and reheating scans. The results have shown that all samples investigated display thermotropic liquid crystallinity. The transition temperatures have ...
The present work discusses the potential and the economic feasibility of DH (district heating) delivery using industrial excess heat from a petrochemical cluster at the Swedish West Coast. Pinch Analysis was used for estimating the DH capacity targets and for estimating the cost of heat exchanger installation. A discounted cash flow rate of return of 10% was used as a criterion for identifying the minimum yearly DH delivery that should be guaranteed for a given DH capacity at different DH sales prices. The study was conducted for the current scenario in which no heat recovery is achieved between the cluster plants and for a possible future scenario in which 50% of the fuel currently used for heating purposes is saved by increasing the heat recovery at the site. The competition between excess heat export and local energy efficiency measures is also discussed in terms of CO2 emission consequences. The maximum capacity of DH delivery amounts today to around 235 MW, which reduces to 110 MW in the future
Plastics - Differential scanning calorimetry (DSC) - Part 2: Determination of glass transition temperature and glass transition step height
0035]FIGS. 4-6 illustrate specific examples of differential scanning calorimetry (DSC) measurements of release agents at viscosities of approximately 8 mPa*s, 40 mPa*s and 77 mPa*s. More specifically, FIG. 4 illustrates a comparative release agent, wherein the release agent has a viscosity of 8 mPa*s. As can be seen from the DSC curve, the peak endothermic melting temperature or Tmp of the release agent is approximately 85° C., i.e., 85° C.+/-1° C., and the melting range of the release agent (Tmr) is in the range of 47° C.+/-1° C. to 105° C.+/-1° C. FIG. 5 illustrates a release agent contemplated herein, wherein the release agent exhibits a viscosity of approximately 40 mPa*s. As can be seen from the DSC curve, the peak endothermic melting temperature or Tmp of the release agent is approximately 84° C., i.e., 84° C.+/-1° C., and the melting range of the release agent (Tmr) is in the range of 43° C.+/-1° C. to 104° C.+/-1° C. FIG. 6 illustrates another release agent contemplated ...
Syndiotactic polystyrene pellets were processed into powder form using mechanical (ball milling, rotor milling) and physicochemical (spray drying) techniques with the intention of using it as feed material for selective laser sintering. New materials are an important component in broadening the application window for selective laser sintering but must meet strict requirements to be used. Particles obtained were characterized in size and shape using SEM imaging, analyzed by software, and compared to the product obtained by conventional ball milling. Rotor milling and spray drying proved capable of making spherical powders, yet only rotor milling achieved particles with a mean diameter within the desired range of 45-97 µm. Subsequently, the obtained powders were examined for the effect each processing technique imparts on the intrinsic properties of the material. Differential scanning calorimetry analysis revealed amorphization for all methods and a reduction in crystallinity after processing, however,
The effect of oxygen content in zirconium on the structure and mechanical properties of the Cu46Zr42Al7Y5 alloy, in the form of melt-spun ribbons and suction-cast rods, was investigated. Two types of Zr, rod and crystal bar of different nominal purities and oxygen contents, were used to synthesize the alloy by arc melting. Rapidly solidified ribbons were produced by melt spinning and their amorphous structures were confirmed by X-ray diffractometry (XRD) and differential scanning calorimetry (DSC). Bulk samples in the form of rods were cast using a special water-cooled suction casting unit attached to the arc melting system. XRD and DSC studies proved the amorphous structure of the bulk alloy synthesized from low-oxygen Zr and partial crystallization of the same alloy for high-oxygen Zr. In both bulk samples, uniformly distributed crystalline particles were identified as yttrium oxides. Higher mean compressive strength of amorphous alloy was observed. The hardness of amorphous phase was close to ...
We therefore used propolis as a lipid material to prepare solid lipid nanoparticles (SLNs); SLNs are proposed bioactive medications for topical intranasal therapy. Suitable formulation parameters were studied and the SLNs obtained by the high shear homogenization method were characterized; a selected formulation was viscosized to increase the residence time. Dimensional, morphological, and solid-state characterizations of the formulated SLNs were performed. In vitro and ex vivo permeation tests of diclofenac sodium, the model drug, and polyphenols were carried out. The propolis amount and surfactant concentration represent the key parameters that affect nanoparticle properties in terms of size, drug and polyphenol content, and physical stability. Size dispersions of about 600nm and 0.4 PI were obtained, which do not change by increasing the viscosity. Drug is encapsulated in SLNs, as demonstrated by FTIR and DSC analyses. ...
TY - JOUR. T1 - Ferroelastic domain structures of the low-temperature phase transition in TlH2PO4. AU - Kim, Kum Bae. AU - Lee, Kwang Sei. AU - Lee, Cheol Eui. PY - 1998/6. Y1 - 1998/6. N2 - The low-temperature II-III phase transition of TlH2PO4 (ferroelastic in phase II) at 230 K (Tc2) was studied by a polarizing microscope between 300 and 80 K. Despite the II-III phase transition at Tc2, the two kinds of ferroelastic domain structures with the (100) and/or (001) and (201) domain boundaries were still observed below Tc2 and were nearly temperature-independent. No new domain structures corresponding to antiferroelectric or ferrielectric orientation states were observed in phase III. The possible intermediate structural phase transition near 130 K suggested by vibrational spectroscopic study [B. Pasquier et al.: Chem. Phys. 171 (1993) 203] was not detected. The transition at Tc2 without optically detectable new domains indicates that the monoclinic crystal system of the phase II persists in phase ...
TY - JOUR. T1 - Crystallization kinetics in liquid crystals with hexagonal precursor phases by calorimetry. AU - Padmaja, Sunkara. AU - Ajita, Narayanan. AU - Srinivasulu, Maddasani. AU - Girish, Sriram Ramchandra. AU - Pisipati, Venkata Gopala Krishna Murthy. AU - Potukuchi, Dakshina Murthy. PY - 2010. Y1 - 2010. N2 - Design and characterization of Schiff based liquid crystalline nO.m compounds exhibiting hexagonal smectic phases are reported. Crystallization kinetics investigations are carried out in the liquid crystals (LCs) exhibiting hexagonal ordered orthogonal and tilted precursor LC phases by calorimetry. The Avrami theory is referred and results are analyzed. Influence of molecular ordering, structure, and dimensionality of the LC precursor phase on kinetics is studied. Effect of shape and flexibility of the molecule for nucleation and growth processes is investigated. Varying rate of kinetics reflects upon the transit of the system from constant type to independent type of nucleation. ...
TY - JOUR. T1 - DNA that is dispersed in the liquid crystalline phases of phospholipids is actively transcribed. AU - Corsi, J.. AU - Dymond, Marcus. AU - Ces, O.. AU - Muck, J.. AU - Zink, D.. AU - Attard, George S.. PY - 2008/5/28. Y1 - 2008/5/28. N2 - We report that a 4.3 kbp linearised T7 DNA plasmid is actively transcribed when it is dispersed in the hexagonal liquid crystalline phase of dioleoylphosphoethanolamine (DOPE).. AB - We report that a 4.3 kbp linearised T7 DNA plasmid is actively transcribed when it is dispersed in the hexagonal liquid crystalline phase of dioleoylphosphoethanolamine (DOPE).. U2 - 10.1039/b801199k. DO - 10.1039/b801199k. M3 - Article. SP - 2307. EP - 2309. JO - Chemical Communications. JF - Chemical Communications. SN - 1359-7345. IS - 20. ER - ...
I have been getting annual thermograms instead of doing mammograms. During my last visit, the consultant noticed an area between my shoulder blades was highlighted green and she suggested that it may have something to do with gallbladder congestion. She referred me to the Miracle Gallbladder and Liver Cleanse book and protocall by Andreas Moritz. I read the book and did the flush 4 months in a row and seemed to have textbook results which consisted of small pea green stones exiting my body. There is a lot of praise for this protocall, but there seems to be an equal amount of skeptcsism about whether or not these are actually gall and liver stones or if they are a by product of the olive oil that is ingested the night before. I was hoping to get your opinions on this cleanse before I go forward with another round. Its not exactly how I want to spend a weekend, but I will continue if it is worth it. Thank You so much! Johnna T. ...
scales or at atomic scales, but virtually no technique offers the ability to monitor and map bias-induced phase transitions at nanometer lengths. The detection of phase transitions at these length scales is crucial for understanding the function of a variety of materials used in energy transduction, harvesting, and piezoelectric actuation. Here, a non-destructive technique is demonstrated using an atomic force microscope tip, which is used to confine an electric field in a small (nanometers) volume of material. By using a special AC waveform applied to the tip, it is possible to listen to the changes in the elastic properties of the material by monitoring the resonant frequency of the tip-sample contact. The technique is applied to a material used in ultrasound transducers and energy harvesting devices to detect and map a voltage-induced phase transition across the surface, and is compared to thermodynamic modeling, providing fresh insight into how these materials function at the relevant ...
Excess heat skin - Facial Sweating - My Excessive Sweating. Revitol Skin Brightener Cream is your safe, herbal-based solution for a beautiful, glowing complexion.
Elkordy, Amal, Forbes, Robert T and Barry, Brian W (2008) Study of protein conformational stability and integrity using calorimetry and FT-Raman spectroscopy correlated with enzymatic activity. European Journal of Pharmaceutical Sciences, 33 (2). pp. 177-190. ISSN 0928-0987 ...
AbeBooks.com: Quantitative X-Ray Diffractometry (9781461395379) by Lev S. Zevin; Giora Kimmel and a great selection of similar New, Used and Collectible Books available now at great prices.
Thermal analysis and calorimetry for carbon neutral capture in liquid , CO2 capture in solid media, Sequestration of CO2 hydrates, in minerals and saline solutions, and chemical looping combustion
Endotherm Life Science Molecules bietet als Auftragsforschungsunternehmen hochwertige Substanzen zur Entwicklung neuer Arzneistoffe für die Medizinische Chemie, und Biomarker für die Entwicklung von diagnostischen Testverfahren an.Die Produktpalette umfasst u.a. fokussierte und diversifizierte Substanzbibliotheken, Referenzstandards, Synthesebausteine, Pharmawirkstoffe und deren Verunreinigungen, Fluoreszenzfarbstoffe sowie Naturstoffe und ihre Metabolite.
We investigate the swelling and shrinking of L-beta lamellar gel phases composed of surfactant and fatty alcohol after contact with aqueous poly(ethyleneglycol) solutions. The height change Delta h(t) is diffusionlike with a swelling coefficient S: Delta h=S root t. On increasing polymer concentration, we observe sequentially slower swelling, absence of swelling, and finally shrinking of the lamellar phase. This behavior is summarized in a nonequilibrium diagram and the composition dependence of S quantitatively described by a generic model. We find a diffusion coefficient, the only free parameter, consistent with previous measurements ...
Reaction calorimeters uncover potential safety issues and provide process information under using real time heat flow or heat flux calorimetry.
A structural and Mössbauer study of Y3Fe5O12 nanoparticles prepared with high energy ball milling and subsequent sintering. Widatallah, H. M.; Johnson, C.; Al-Harthi, S. H.; Gismelseed, A. M.; Al-Rawas, A. D.; Stewart, S. J.; Elzain, M. E.; Al-Omari, I. A.; Yousif, A. A. // Hyperfine Interactions;2008, Vol. 183 Issue 1-3, p87 The influence of ball milling and subsequent sintering of a 3:5 molar mixture of Y2O3 and α-Fe2O3 on the formation of nanocrystalline Y3Fe5O12 (YIG) particles is studied. Pre-milling the mixture for 100 h lowers the onset temperature at which the material forms to 900°C which is 200°C... ...
K.Baumgartner, S. Oelmeier, J. Hubbuch, The influence of mixed salts on the capacity of HIC adsorbers and a correlation to the surface tension and the aggregation onset temperature, 34th International symposium on the separation of proteins, peptides and polynucleotides (ISPPP), Würzburg, Germany, 05. November 2014.. ...
While this new bra might sound like the next best thing since sliced bread, critics argue that the thermal technology may be premature. Hypothetically, its conceivable that malignant processes would have a temperature gradient compared to non-malignant tissues, says Dr. Therese Bevers, medical director of the cancer prevention center at the University of Texas M.D. Anderson Cancer Center. But that gradient may not be very large.. Medical experts say that thermograms are already being used by the industry to detect abnormal cells, but unfortunately the hot and cold spots that are supposed to indicate cancerous and non-malignant tissue, respectively, are not always accurate. We see some thermograms come back as abnormal, and we do all kinds of imaging with mammogram, ultrasound and MRI and we follow the women and nothing develops, says Bevers. And we have women with breast cancers that are not seen on the thermograms.. So, can First Warnings new sport bra really predict cancer? It is ...
In order to facilitate the study of reactive-compositional porous media processes we develop a virtual kinetic cell (single-cell model) as well as a virtual combustion tube (one-dimensional model). Both models are fully compositional based on an equation of state. We employ the models to study phase behavior sensitivity for in situ combustion, a thermal oil recovery process. For the one-dimensional model we first study the sensitivity to numerical discretization errors and provide grid density guidelines for proper resolution of in situ combustion behavior. A critical condition for success of in situ combustion processes is the formation and sustained propagation of a high-temperature combustion front. Using the models developed, we study the impact of phase behavior on ignition/extinction dynamics as a function of the operating conditions. We show that when operating close to ignition/extinction branches, a change of phase behavior model will shift the system from a state of ignition to a state ...
We discuss an open driven-dissipative many-body system, in which the competition of unitary Hamiltonian and dissipative Liouvillian dynamics leads to a nonequilibrium phase transition. It shares features of a quantum phase transition in that it is interaction driven, and of a classical phase transition, in that the ordered phase is continuously connected to a thermal state. We characterize the phase diagram and the critical behavior at the phase transition approached as a function of time. We find a novel fluctuation induced dynamical instability, which occurs at long wavelength as a consequence of a subtle dissipative renormalization effect on the speed of sound.. ...
The cooling of used sand which is still hot can be best achieved using the principle of vaporization. Spraying water and ensuring good ventilation can take away a large part of the heat. The vaporization of 1 % of water brings a cooling of around 27K. A cooling of the mold material through ventilation alone is less effective, as its heat absorption capacity is low. The cooling air mainly serves as a medium to transport the water vapor.. The determination of the amount of water and air required for vaporization can be formalized via three calculation steps of a combined energy-water balance and can be represented in a diagram ...
The 96 site Elite Klone Machine is a Commercial Level propagation system. These systems are specifically designed for serious growers. Made of grey ABS plastic shell for less heat absorption from lights above and greater reflective properties to promote efficient growth. Has alpha/numeric lid to categorize different plant species with ease as well as colored Klone collars to visually differentiate plant species using a color coded pattern determined by you. Larger fan to introduce more oxygen to the grow chamber with even greater cooling effects. Optional humidity dome with integrated vents allow you to adjust the humidity level within the dome and provide more control.. Sold in Quantity of: 1. Warranty Offered: 1. ...
The 144 site Elite Klone Machine is a Commercial Level propagation system. These systems are specifically designed for serious growers. Made of grey ABS plastic shell for less heat absorption from lights above and greater reflective properties to promote efficient growth. Has alpha/numeric lid to categorize different plant species with ease as well as colored Klone collars to visually differentiate plant species using a color coded pattern determined by you. Larger fan to introduce more oxygen to the grow chamber with even greater cooling effects. Optional humidity dome with integrated vents allow you to adjust the humidity level within the dome and provide more control.. Sold in Quantity of: 1. Warranty Offered: 1. ...
A system for treating vision disorders is disclosed. The system includes a heating device able to heat predetermined areas of the corneal tissue of an eye. The energy for heating is typically generated in the form of laser light or infrared that cause the tissue at that predetermined area to heat and shrink. The shrinkage shifts a plug or portion of the cornea with respect to the remainder of the eye to change the shape of the corneal surface and correct the problematic refractive error. A heat absorption modifier is used to avoid damage to the epithelial layer as energy is passed therethrough.
Extended indirect calorimetry as a physiological phenotyping tool in mouse nutritionalintervention studies, with a focus on metabolic programming by ...
Abstract: Very recently, the discovery of a marginal, or practically perfect, phase transition (MPT or PPPT) at finite temperature in the 2-leg ladder Ising model with trimer rungs was reported [1]. The MPT or PPPT stems from a new mathematical structure that has not appeared before in phase-transition problems. This opens the door to simulations and utilizations of the spontaneous phase-transition phenomena in one-dimensional systems, despite the proof that phase transitions do not exist in the one-dimensional Ising models with short-range interactions back to year 1924 [2]. Naturally, the urgent fundamental and practical question is how we, now guided by the new light on phase transitions, can find the next cases of MPT or PPPT in one-dimensional systems. Here, I present a generalization of the original idea to a new parents-children Ising model with ice-cream-cone rungs, and exactly prove that the model possesses the same mathematical structure and thus MPT or PPPT. Yet, the ice-cream-cone ...
The synthesis and thermotropic properties of four homologous series of salicylaldimine-based dimer liquid crystals are reported. Two 4-(4-alkoxy-2-hydroxybenzylideneamino) benzoyloxy groups are connected to a central part consisting of a 1,3-phenylene, 1,5-pentylene, 2,2-dimethyl- 1,5-pentylene or 3,3-dimethyl-1,5-pentylene unit. The terminal alkoxy chains have been varied from 4 to 16 carbon atoms in length. All the compounds exhibit liquid crystalline phases whose behaviour depends on the nature of the central part and the length of the alkoxy terminal chains. All compounds of the series with the central phenyl part exhibit enantiotropic B-phases, and the sequence B-6 - B-1 - B-2 on increasing terminal chain length was observed. Replacement of the phenyl group with a pentyl central group partly suppresses the formation of B-phases. The longer homologues of this series show the B1 phase, while the shorter exhibit an intercalated SmCc mesophase. The introduction of methyl substituents to the ...
The paper frankly discusses some of the limits of using enthalpy arrays. For example, since the fragment should be present at a higher concentration than enzyme, very tight binders would require unfeasibly low enzyme concentrations. This limits the practical range of the technique to inhibitors with KIs ranging from ~500 nM to 2 mM. Also, as Morgen G observed in a comment to the last post, this is more of a biochemical assay (monitoring the heat of an enzymatic reaction) rather than what most people think of when you say the word calorimetry (monitoring the heat of binding, as in the case of isothermal titration calorimetry). Still, enthalpy arrays seem pretty cool; hopefully folks will warm to them ...
A system contains $x$ mole of material, with surface area $S$ is pressed by a mass $M_1$ (no fraction and no any other outer forces involves). Let $\Delta H_\mathrm{l\rightarrow g}$ be the transition enthalpy from liquid to gas. The system is position in $(T,P_1)$ such that the material phase is liquid for those temperature and pressure values ($T$ and $P_1$). Now instantaneously the mass $M_1$ is decreased to to an unknown value which we denote $M_2$ so the pressure decreases. In case that the temperature stays constant until the inner pressure is equal to the outer pressure $(T,P_2:=\frac{M_2g}{S})$ system gets to back to equilibrium, and the material phase in $(T,P_2)$ is gas, I wish to calculate how much energy was absorbed by the system till it gets to pressure equilibrium $(T,P_2)$.. In the question is says that the volume of the liquid can be neglected when compared to gas volume. And that the volume of the water is independent of the pressure.. What I did so far:. The chemical ...
This volume explores the creation, study, and processing of new liquid-crystalline polymers. It covers not only the chemistry of liquid-crystalline polymers, but also the physics and engineering aspects of these materials. A wide range of topics is covered, including syntheses of main-chain and side-chain LCPs, structural characterization of LP, rheology and processing, and applications such a electro-optics and self-reinforcing blends.
Fraden et al. and Teramoto et al. have studied the entropy driven phase transition of monodisperse suspensions of purely repulsive rods from an isotropic to an aligned nematic phase experimentally. [1-2] The phase transition has also been studied theoretically and computationally. [3-5] For Fraden et al. the motivation to study hard particle binary mixtures of multiple aspect ratios stems from the desire to ultimately understand the impact of polydispersity on the phase separation of concentrated suspensions of rodlike macromolecules. F-actin, microtubules, and DNA are all examples of biological rodlike particles in which length and diameter polydispersity are common. Theoretical studies of binary hard-rod mixtures predict that in addition to isotropicnematic (I-N) coexistence, isotropic-nematic-nematic (I-N-N), isotropic-isotropic (I-I), and nematic-nematic (N-N) coexistence are possible when the length or diameter ratios of the particles are large enough [6 -12]. Fraden et al. have presented ...
Sharp phase boundaries Small changes in climate can show big effects - i.e. number of events. Climate Phase change and amplification Frost and salt crystallisation Phase transitions at precise thermo-hygrometric conditions
In this article, three formulations of two phase compositional Darcy flows taking into account phase transitions are compared. The first formulation is the so called natural variable formulation commonly used in reservoir simulation, the second has been introduced in [14] and uses the phase pressures, saturations and component fugacities as main unknowns, and the third is an extension to general compositional two phase flows of the pressure pressure formulation introduced in [2] in the case of two compo-nents. The three formulations are shown to lead to equivalent definitions of the phase transitions for our gas liquid thermodynamical model. Then, they are compared numerically in terms of solution and convergence of the Newton type non linear solver on several 1D and 3D test cases including gas appearance and liquid disappearance. The 3D discretization is based on the Vertex Approximate Gradient (VAG) scheme [10] and takes into account discontinuous capillary pressures.