Dienestrol: A synthetic, non-steroidal estrogen structurally related to stilbestrol. It is used, usually as the cream, in the treatment of menopausal and postmenopausal symptoms.

Eight of the plaintiffs, including Linda Ferrigno, named in the amended complaint in the first action and in the complaint in the second suit (hereafter the complaint), are daughters whose mothers when pregnant with each took a synthetic estrogen prescribed by their doctors to prevent miscarriage. The remaining plaintiffs are either parents or spouses of those daughters.. The complaint alleges that as a direct consequence of the mothers taking the drugs their daughters developed a variety of serious ailments, including cancer of the vagina and cervix, adenosis and certain structural changes.. From 1946 to 1972, the complaint says, the 22 defendants manufactured, distributed and sold large quantities of the kind of prescription drugs ingested by the mothers. Collectively denominated as DES by plaintiffs, the drugs are alleged to have been diethylstilbestrol, stilbestrol and dienestrol.. According to the complaint, 12 of the defendants, at an unspecified time, joined together to form an ...

Female NMRI mice were given injections of different doses of 17β-estradiol, 17α-estradiol, diethylstilbestrol (DES), dienestrol, trans-stilbene, progesterone, testosterone, 5α-dihydrotestosterone, or olive oil for the first 5 days after birth. When the females were killed at 8 weeks after birth, all the estrogens, effective at different dose levels (10-2 to 5 µg/day), had resulted in the display by several of the cervicovaginal preparations studied of a heterotopic columnar epithelium (HCE) in regions where females given injections of olive oil, testoster-one, 5α-dihydrotestosterone, progesterone, or trans-stilbene had only the normal squamous epithelium. The further fate of the HCE was followed at two later age stages, 36 to 52 weeks and 14 to 17 months. The HCE developed into glandular-like structures penetrating into the stroma and justifying the designation of adenosis. DES resulted in a more pronounced adenosis than did 17β-estradiol; in both cases, metaplasia was a striking component ...

Dienestrol is a synthetic, non-steroidal estrogen. Estrogens passively diffuse into target cells of responsive tissues, complex with the estrogen receptors, and enter the cells nucleus to initiate or enhance gene transcription of protein synthesis after binding to DNA ...

A metallocene catalyst is provided which comprises the product obtained by combining (a) a metallocene procatalyst, preferably one containing a bridging group possessing at least two bulky groups, and (b) a cation-generating cocatalyst. A process for activating a metallocene procatalyst is also provided which comprises combining the metallocene procatalyst with the components of a cation-generating cocatalyst.

The results of this study show that the synthesis of the inner mitochondrial membrane phospholipid, cardiolipin, is markedly inhibited following infection of human embryonic lung or hamster embryo fibroblast cells with herpes simplex virus type 1 or 2. The synthesis of other phospholipids, i.e., phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, and phosphatidylinositol, is relatively unaffected.

This invention uses a new method of producing ionic metallocene compounds. These compounds are useful as catalysts for polymerization of olefins, primarily propylene. This method uses an ionizing agent which ionizes the neutral metallocene compound. The ionizing ionic compound does not contain an active proton and contains a carbonium, oxonium or sulfonium cation. The anion of the ionizing ionic compound is not coordinated or is only loosely coordinated to the metallocene cation and is chemically unreactive with the metallocene cation. Examples of such compounds are triphenylcarbenium tetrakis(pentafluorophenyl)boronate, triphenylcarbenium tris(pentafluorophenyl)phenyl boronate and triphenylcarbeniumtris(pentafluorophenyl)4-trimethylsilyl-2,3,5,6-tetrafluorophenylboronate. The process of making catalysts with this invention produces catalysts having high activity and does not produce by-products which can inhibit catalyst activity. This new synthesis is a clean reaction which does not produce a Lewis

Chemically homogeneous cycloolefin copolymers of polycyclic olefins, such as, for example, norbornene or tetracyclododecene, with cycloolefins and/or acyclic olefins are obtained without ring opening and in a high space-time yield if a catalyst system is used which comprises an aluminoxane and a stereorigid metallocene compound of an element from groups IVb to VIb, of the formula the part of the metallocene molecule formed by M1 and the substituents R16-R17 having C1-symmetry or being in the meso-form.

The novel metallocenes of the formula I in which, preferably, M1 is Zr or Hf, R1 and R2 are alkyl or halogen, R3 and R4 are hydrogen, R5 and R6 are alkyl or haloalkyl, -(CR8R9)m-R7-(CR8R9)n- is a single- or multi-membered chain in which R7 may also be a (substituted) hetero atom, m+n is zero or 1, and R10 is hydrogen, form, together with aluminoxanes as cocatalysts, a very effective catalyst system for the preparation of polyolefins or high stereospecificity and high melting point. Polyolefins with unique or improved properties are obtained by polymerizing an olefin in the presence of a metallocene combined with a cocatalyst, wherein the metallocene is preferably a zirconocene or a hafnocene, and the Zr or Hf central atom is coordinated with two ligands which are derivatives of 2-substituted indenyl nuclei and which are substituted with at least one and up to four groups (e.g. aliphatic or aromatic groups) on the six-member rings of the indenyl nuclei. The indenyl nuclei are optionally substituted at

Metallocenes containing aryl-substituted indenyl derivatives as ligands, process for their preparation, and their use as catalysts. A very effective catalyst system for the polymerization or copolymerization of olefins comprises a cocatalyst, preferably an aluminoxane or a supported aluminoxane, and a metallocene of the formula I ##STR1## in which, in the preferred form, M1 is Zr or Hf, R1 and R2 are halogen or alkyl, R1 is alkyl, R4 to R12 are alkyl or hydrogen and R13 is a (substituted) alkylene or heteroatom bridge. The metallocenes, in particular the zirconocenes, produce polymers of very high molecular weight, in the case of prochiral monomers polymers of very high molecular weight, very high stereotacticity and very high melting point, at high catalyst activities in the industrially particularly interesting temperature range between 50 and 80 C. In addition, reactor deposits are avoided by means of supported catalyst systems.

For info regarding Fibroblast Cell Culture Protocols, please contact Leslie Gordon at [email protected], or Wendy Norris at [email protected].

The present invention relates to a polynuclear metallocene compound of the formula I ##STR1## a process for their preparation and their use as a catalyst for olefin polymerization.

The market predictions for various resins and products are changing rapidly but gradually it becomes known which directions are most likely to be affected and why. Several chapters contribute to this understanding.

Tired of Hot Melt Headaches? Tired of high prices and poor service? Astro Packaging has the cure. Specialists in hot melt glue & adhesive equipment.

Many chemicals are subject to strict legal stipulations.. Our offer is not directed toward consumers within the meaning of Section 13 of the German Civil Code (BGB), but exclusively toward companies (Section 14 of the German Civil Code), legal entities under public law or public-law special funds. Our products - insofar as a deviating agreement has not been reached - may not be used in unprocessed form as additives for foodstuffs or animal feed, medications for humans or animals, cosmetics or for in-vivo diagnostics purposes.. Notice: Your complete company data is required for purchasing chemicals. All new or additionally added addresses are initially examined by order processing. Please note that country-specific export restrictions apply to some products. ...

As reported in our September K preview, Brampton Engineering (be-ca.com) showed a streamlined FlexStack SCD (Streamlined Coextrusion Die) die. It is about half as tall of the suppliers standard SCD, cutting residence and purging times. Macro Engineering & Technology (macroeng.com) showed a seven-layer TaperPack Die, the key component of its DXL-7000 Series of double-bubble lines. Addex Inc. (addexinc.com) displayed a simplified version its original autoprofile External Gauge Control air ring. Macchi (macchi.it) ran a nine-layer line that sandwiched barrier layers between layers of metallocene LLDPE and LDPE ...

Diethylstilbestrol (DES), hexestrol and dienestrol (oestrogenic hormones) are collectively called stilbenes, which are banned worldwide for use in food producing animals. The stilbenes are growth promoting agents used in meat production. The use of anabolic agents has been banned within the European community since 1986, because of the potential risk to consumers from meat containing any residues. Stilbenes are also thought to be capable of initiating the carcinogenic process at small concentrations.. ...

This is a complete list of estrogens and formulations that are approved by the FDA and available in the United States. Estrogens are used as hormonal contraceptives, in hormone replacement therapy, and in the treatment of gynecological disorders. Conjugated estrogens (Premarin) - 0.3 mg, 0.45 mg, 0.625 mg, 0.9 mg, 1.25 mg, 2.5 mg Esterified estrogens (Amnestrogen, Estratab, Evex, Femogen, Menest) - 0.3 mg, 0.625 mg, 1.25 mg, 2.5 mg Estradiol (Estradiol, Gynodiol, Innofem) - 0.5 mg, 1 mg, 2 mg Estradiol acetate (Femtrace) - 0.45 mg, 0.9 mg, 1.8 mg Estropipate (Estropipate, Ogen .625, Ogen 1.25, Ogen 2.5, Ogen 5, Ortho-Est) - 0.75 mg, 1.5 mg, 3 mg, 6 mg Synthetic conjugated estrogens (Cenestin, Enjuvia) - 0.3 mg, 0.45 mg, 0.625 mg, 0.9 mg, 1.25 mg Atypical (nitrogen mustard alkylating antineoplastic): Estramustine phosphate sodium (Emcyt) - 140 mg Discontinued: Chlorotrianisene (TACE) Dienestrol (Synestrol) Diethylstilbestrol (DES, Diethylstilbestrol, Stilbestrol, Stilbetin) Ethinylestradiol ...

The general name metallocene is derived from ferrocene, (C5H5)2Fe or Cp2Fe , systematically named bis(η5-cyclopentadienyl)iron(II). According to the IUPAC definition, a metallocene contains a transition metal and two cyclopentadienyl ligands coordinated in a sandwich structure, i. e., the two cyclopentadienyl anions are co-planar with equal bond lengths and strengths. Using the nomenclature of hapticity, the equivalent bonding of all 5 carbon atoms of a cyclopentadienyl ring is denoted as η5, pronounced pentahapto. There are exceptions, such as uranocene, which has two cyclooctatetraene rings sandwiching a uranium atom.. In metallocene names, the prefix before the -ocene ending indicates what metallic element is between the Cp groups. For example in ferrocene, iron(II) or ferrous is present.. In contrast to the more strict definition proposed by IUPAC, which requires a d-block metal and a sandwich structure, the term metallocene and thus the denotation -ocene, is applied in the chemical ...

f-Block Metallocene refers to a class of organometallic sandwich compounds with f-Block metal and electron-rich ligands like cyclopentadienyl anion. The first prepared and well-characterized f-block metallocenes were the tris(cyclopentadienyl) lanthanide complexes, (C5H5)3Ln (Ln = La, Ce, Pr, Nd, Sm and Gd). However, their significance is limited more to their existences and structures than to their reactivity. The cyclopentadienyl ligands of f-block metallocenes were considered as inert ancillary ligands, only capable of enhancing their stability and solubility, but not their reactivity. In addition, only late and small metals in the lanthanide series, i.e., elements from Sm to Lu, are trivalent metallocene complexes, [(C5H5)2LnZ]n In 1980, the pentamethylcyclopentadienyl ligand, C5Me− 5, was introduced to prepare the lanthanide complexes with all metals in the series. Apart from improving the stability and solubility of the complexes, it was demonstrated to participate in organometallic ...

A catalyst composition for polymerizing olefins to polymers having bimodal molecular weight distribution comprises two transition metal-containing metallocene compounds, a magnesium compound, an alcohol, an aluminum containing co-catalyst and a polymeric support. The transition metal in one of the metallocene compounds is zirconium and the transition metal in the second metallocene compound is selected from the group consisting of titanium, vanadium and hafnium. Polyolefin polymers made using the catalyst composition have broad molecular weight distributions and are useful in film and blow molding applications.

Description: This article discusses small molecule elimination from group IVB (Ti, Zr, Hf) amido complexes. An ab initio quantum chemical analysis of HX (X = H, CH₃, Cl, NH₂, SiH₃) elimination by group IVB (Ti, Zr, Hf) amidos (H₂(X)M - NH₂ → H₂M = NH + HX), of interest in the context of CVD precursor design, is reported. ...

Description: This article discusses small molecule elimination from group IVB (Ti, Zr, Hf) amido complexes. An ab initio quantum chemical analysis of HX (X = H, CH₃, Cl, NH₂, SiH₃) elimination by group IVB (Ti, Zr, Hf) amidos (H₂(X)M - NH₂ → H₂M = NH + HX), of interest in the context of CVD precursor design, is reported. ...

A comparative survey of published work on the reactions of organic derivatives of the Group IVB elements has been made, and the function of these elements in such reactions is discussed. The influence of the trimethylsilyl- and trimethyl- -germyl- substituents on the strengths of some carboxylic acids indicates that the inductive electron-releasing effect is slightly greater, and steric effects consider- -ably less, in the latter group. The alkaline cleavage of numerous tetra-organo- -silanes, -germanes, and -stannanes has been examined. The absolute and relative rates vary widely with the constitution of the compounds, but the germanes are generally much less reactive than the silanes, which are rather less reactive than the stannanes. The tetraorgano-stannanes are often less reactive than might be anticipated. The results are interpreted in terms of decreasing availability of the vacant d-orbitals for transition- state stabilisation as we descend Group IVB. The trimethylaralkyl-germanes and ...

Read Facile preparation and goodperformance of nano-Ag/metallocene polyethylene antibacterial coatings, Journal of Coatings Technology and Research on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.

The past 15 years have witnessed tremendous advances in the design and use of organometallic complexes as precatalysts for olefin polymerization. Most recently, an intense search has been started in next-generation single-site catalysts. New approaches have been taken to ligand design.

We report the synthesis and analysis of metallocenes (ferrocene, chromocene, ruthenocene, vanadocene, tungstenocene-dihydride) encapsulated in single wall carbon nanotubes (SWNTs). In the case of ferrocene, efficient filling of the SWNTs was accomplished from both the liquid and the vapor phase. The other two metallocenes were filled from the vapor phase. High resolution transmission electron microscopy reveals single molecular chains of metallocenes inside SWNTs. Molecules move under the electron beam in the SWNTs indicating the absence of strong chemical bonds between each other and the SWNT wall. Their movement freezes after short illumination as a result of irradiation damage. Energy dispersive X-ray spectrometry confirms the presence of iron, chromium, ruthenium, vanadium and tungsten.

TY - JOUR. T1 - Ecto-ganglioside-sialidase activity of herpes simplex virus-transformed hamster embryo fibroblasts. AU - Schengrund, Cara Lynne. AU - Rosenberg, Abraham. AU - Repman, Mary Ann. PY - 1976/9/1. Y1 - 1976/9/1. N2 - Cellular location of ganglioside-sialidase activity was determined in confluent hamster embryo fibroblasts transformed with herpes simplex virus type 2. Approximately equal specific activities of ganglioside-sialidase activity were found to be associated with the crude lysosomal and crude plasma membrane fractions isolated from whole cell homogenates. Whole transformed cells hydrolyzed exogenous ganglioside substrate, suggesting a partial location of the cellular sialidase on the outer surface of the plasma membrane of these cells. Intact cells were treated with the diazonium salt of sulfanilic acid, a nonpenetrating reagent inhibitory to ecto-enzymes (DePierre, J. W., and M. L. Kamovsky. 1974. J. Biol. Chem. 249: 7111-7120). Cytoplasmic lactate dehydrogenase activity was ...

LIST OF ALL EURO-DIAGNOSTICA PRODUCTS AND DATA SHEETS ». Zeranol is a xenobiotic anabolic agent with estrogenic growth promoting activities, which is legally used in several countries. However, in the EC the anabolics have been banned since 1986. Because of close structural resemblance the antibody cross-reacts with both zeranol and its main metabolites and with the mycotoxin zearalenone and its main metabolites. The Zeranol-EIA is recommended for the screening of urine samples on the presence of zeranol (100%), taleranol (133%), zearalanone (100%), a. -zearalenol (90%), zearalenone (75%) and ß. -zearalenol (70%). The stilbenes (diethylstilbestrol, hexestrol and dienestrol), 17ß-oestradiol, progesterone and testosterone show a cross-reactivity of less than 0.01%. With this Zeranol-EIA a detection limit of 0.1 ng/ml urine can be obtained.. ...

Carbohydrate - metallocene conjugates. Metallocenes are organometallic compounds characterized by a transition metal central atom (M) bound to cyclopentadienide (Cp-/C5H5-) ligands, the general formula of metallocenes being Cp2M. Titanocene dichloride was among the first non-platinum organometallics investigated as promising anticancer agents. Although its clinical trials were stopped because of low efficacy and other drawbacks, the last two decades have witnessed renewed research interest in anticancer metallocenes. We have started a programme aimed at improving cytotoxic activity and pharmacological properties of metallocenes by their conjugation to carbohydrates, iminosugars and selected heterocycles. Carbohydrates and iminosugars have typicaly 3 - 6 functional groups that can be modified to ameliorate cytotoxic profile, bioavailability, solubility, biocompatibility, and hydrophobic/hydrophilic balance of the resulting metallocene-carbohydrate conjugate. Recently, we have extended this ...

Negishi reagent [Cp2ZrBu2] derived from zirconocene dichloride using was used for high-stereoselective and regioselective coupling reaction or cyclization. For example, multisubstituted pentacene derivatives having high carrier mobility were synthesized by Negishi reagent. ...

The invention includes a hot melt adhesive composition that includes at least one of an isotactic copolymer of butene-1 and a metallocene catalyzed propylene homopolymer, a tackifying resin, and, optionally, a wax. The adhesive composition initially exhibits adhesion quality and subsequently non-adhesion quality. The invention also includes methods of using the adhesive composition for temporarily bonding substrates.

Cellular location of ganglioside-sialidase activity was determined in confluent hamster embryo fibroblasts transformed with herpes simplex virus type 2. Approximately equal specific activities of ganglioside-sialidase activity were found to be associated with the crude lysosomal and crude plasma membrane fractions isolated from whole cell homogenates. Whole transformed cells hydrolyzed exogenous ganglioside substrate, suggesting a partial location of the cellular sialidase on the outer surface of the plasma membrane of these cells. Intact cells were treated with the diazonium salt of sulfanilic acid, a nonpenetrating reagent inhibitory to ecto-enzymes (DePierre, J.W., and M. L. Karnovsky. 1974. J. Biol. Chem. 249:7111-7120). Cytoplasmic lactate dehydrogenase activity was not inhibited by this treatment, and mitochondrial succinate dehydrogenase activity was inhibited only 10%, indicating that intracellular enzymes were not affected. 5-Nucleotidase activity was diminished 90%, and sialidase very ...

In this thesis a detailed ab initio theoretical study of organothorium chemistry is presented. The first part is devoted to examining both the bonding in and the reaction chemistry of various substituted thorium complexes. Using the chlorine ligand as a model for the usual cyclopentadienyl groups found in these systems, we examine the bonding of hydrogen and methyl ligands to thorium. Frequent comparisons with the experimental results on similar species are made. In addition, by contrasting the bonding in the thorium complexes with the bonding in the analogous Group IVB systems, a qualitative and quantitative picture of bonding, as the atomic number of the metal becomes larger, can be obtained. The reaction chemistry is studied via two different sets of processes. In the first, the deuterium (D2) exchange reaction with a thorium-hydrogen bond is examined. Several studies have been done previously, both experimentally and theoretically, on the Group IVB exchange reactions. Hence, there is enough ...

LOCATION: Erwin Schrödinger Lecture Hall, 5th floor, Boltzmanngasse 5, 1090 Vienna. ABSTRACT: One of the main research lines in magnetism is to embed the spin degrees of freedom into a molecular unit, taking advantage of the monodispersity of an ensemble of synthesized molecules with identical properties. The field of molecular spintronics aims to realize logic or storage devices, addressing the properties of single or few magnetic molecules deposited on opportune substrates/electrodes. The characterization of molecule-substrate interactions is therefore very timely and has raised in the last years a broad interest in the physics and chemists communities.. Along this line, I will present a theoretical density-functional investigation of magnetic molecule-substrate systems. The focus has been on single ion molecules, namely TM-phthalocyanines (TM=transition metals) [1,2], metallocenes (e.g. CoCp2) [3] and Ln double-deckers (e.g. TbPc2) [4,5], and we have investigated in detail the magnetic ...

A variety of metal based ROMP initiators have been developed over the past several years that allow precise control of polymer structure. Recently initiators based on molybdenum and ruthenium that provide control of the double bond geometry of the resulting polymers. Many of these also provide precise control of the tacticity of the backbone. Metallocene catalysts provide good models for thiis control. ...

Process for the preparation of the catalyst system, according to which a mixture is prepared of a halogenated neutral metallocene derived from a transition metal chosen from groups IIIB, IVB, VB and VIB of the Periodic Table and of an organoaluminium compound, and an ionising agent is added thereto. (Co)polymerisation process according to which a mixture of a halogenated neutral metallocene as defined above and of an organoaluminium compound is prepared and the olefin is brought into contact with this mixture and an ionising agent is added thereto.

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The use of diethylstilbestrol DES in large and repeated doses in the successful treatment of sixty-eight cases of threatened abortion is presented.

A tin-plating or aluminum-plating surface treated steel material with excellent corrosion resistance containing an intermetallic compound composed of one or more Group IIa (alkaline earth metal) elements and one or more Group IVb elements in a tin-based plating layer or aluminum-based plating layer on the surface of a steel material. For a tin-based plating layer, the long diameter of the intermetallic compound massive bodies is 1 82 m or greater and the short diameter/long diameter ratio is at least 0.4. For an aluminum-based plating layer, the long diameter of the intermetallic compound massive bodies is 10 .mu.m or greater and the short diameter/long diameter ratio is at least 0.4.

(C5Me5)2Y(η3-C3H5) reacts with 9-borabicyclo[3.3.1]nonane, 9-BBN, to form single crystals containing both a borane-substituted allyl complex, (C5Me5)2Y[η3-C3H4(BC8H14)], and a borohydride, (C5Me5)2Y(μ-H)2BC8H14, that can be synthesized directly from 9-BBN and the yttrium hydride, [(C5Me5)2YH]x.

0026]Non-limiting examples of metallocene catalyst components consistent with the description herein include, for example cyclopentadienylzirconiumAn; indenylzirconiumAn; (1-methylindenyl)zirconiumAn; (2-methylindenyl)zirconiumAn, (1-propylindenyl)zirconiumAn; (2-propylindenyl)zirconiumAn; (1-butylindenyl)zirconiumAn; (2-butylindenyl)zirconiumAn; methylcyclopentadienylzirconiumAn; tetrahydroindenylzirconiumAn; pentamethylcyclopentadienylzirconiumAn; cyclopentadienylzirconiumAn; pentamethylcyclopentadienyltitaniumAn; tetramethylcyclopentyltitaniumAn; (1,2,4-trimethylcyclopentadienyl)zirconiumAn; dimethylsilyl(1,2,3,4-tetramethylcyclopentadienyl)(cyclopentadienyl)zirco- niumAn; dimethylsilyl(1,2,3,4-tetramethylcyclopentadienyl)(1,2,3-trimethylcyclope- ntadienyl)zirconiumAn; dimethylsilyl(1,2,3,4-tetramethylcyclopentadienyl)(1,2-dimethylcyclopenta- dienyl)zirconiumAn; dimethylsilyl(1,2,3,4-tetramethylcyclopentadienyl)(2-methylcyclopentadien- yl)zirconiumAn; ...

Summary of Facts and Submissions. I. The grant of European patent No. 0 751 965 in respect of European patent application No. 95 914 085.6, based on International patent application No. PCT/US95/03348 (which had been published as WO-A-95/26370), filed on 24 March 1995 and claiming priority of 25 March 1994 of an earlier application in the USA (08/218277), was announced on 25 March 1998 (Bulletin 1998/13). The patent contained 14 claims.. Claims 1 to 5, 7, 10 and 11 as granted read, respectively, as follows:. 1. A process for transitioning from a polymerization reaction catalyzed by a first catalyst to one catalyzed by a second catalyst comprising a metallocene catalyst, wherein said first and second catalysts are incompatible, said process comprising the steps of:. a) discontinuing the introduction of the first catalyst into a reactor;. b) introducing into the reactor an irreversible catalyst killer in an amount greater than about 1 molar equivalent based on the total gram atom metal of the ...

The metallocene catalyst system Cp2ZrCl2-methylaluminoxane showed surprisingly high activity for 1-hexadecene, and high concentrations of comonomer could be incorporated into the copolymer compared with a heterogeneous titanium catalyst. A temperature rising elution fractionation (TREF) fractogram of the copolymer revealed it to have narrow branching distribution, much narrower than in commercial linear low density polyethylene, and to have features in common with a commercial low density polyethylene. ...

The Arabidopsis autoimmune mutant, ((exhibits constitutive pathogen resistance responses including higher degrees of endogenous salicylic acid (SA), which can be an important signaling molecule for pathogen protection responses. flowering phenotype of and also have a unique function managing flowering timing which function is unbiased from its function in pathogen protection. genome provides 20 associates in the CNGC family members, which are categorized into four groupings (group I-IV), where group IV is split into subgroup IVA and IVB further. 2 This extension might indicate diverse biological assignments of CNGCs in plant life. They have already been implicated within a diverse selection of natural phenomena such as for example protection responses, pollen pipe growth, ion thermo-tolerance and homeostasis.2,3 Furthermore, recent electrophysiological research showed that place CNGCs tend Ca2+ permeable stations that get excited about a number of physiological phenomena.3-5 Group IVB comprises ...

The crystallization and morphology of very-low-density polyethylene (VLDPE) and ultra-low-density polyethylene (ULDPE) blends with isotactic polypropylene (PP) were studied by differential scanning calorimetry (DSC) and hot-stage optical microscopy (HSOM) with polarized light. In particular, the isothermal crystallization of PP in molten PE was investigated. A polypropylene homopolymer was melt-blended with six types of VLDPEs and ULDPEs, with variations in branch content and length and in molecular weight. All the blends contained 20% PP by mass. It was found that the crystallization temperatures of PP and PE changed in the blends, and the crystallization of PP was affected by branch length and content and by the molecular weight of the PE, indicating a certain degree of miscibility between PP and PE. The isothermal crystallization rate of PP decreased in the blends; in particular, the crystallization rate of PP was slower in the ULDPE with lower MFI, suggesting that crystallization of PP was ...

TY - JOUR. T1 - Recent developments in olefin polymerizations with transition metal catalysts. AU - Imanishi, Yukio. AU - Naga, Naofumi. PY - 2001/10. Y1 - 2001/10. N2 - Discovery of effective homogeneous transition metal catalysts for olefin polymerization must be one of the most dramatic technologies for polymer synthesis in the 1980s. Especially, development of group 4-metallocene catalysts not only improved the property of manufactured polyolefins but also made us possible to synthesize new type polyolefins. A large number of studies have also been made on structure and property of the resultant polyolefins with the advance of catalyst technology. Over the past few years, trend in catalyst development has moved from modification of group 4-metallocene catalysts to search for new generation catalysts, such as non-metallocene catalysts and late transition-metal catalysts. Some of the new catalysts can proceed specific polymerizations, which are not achieved with existent olefin polymerization ...

TY - CONF. T1 - Polyolefins containing `reactive p-methylstyrene groups. T2 - Proceedings of the 1998 56th Annual Technical Conference, ANTEC. Part 1 (of 3). AU - Chung, Tze-chiang. PY - 1998/1/1. Y1 - 1998/1/1. N2 - A new class of polyolefin co- and terpolymers containing `reactive p-methylstyrene groups will be discussed, which includes high Tm approximately 160 °C thermoplastics to low Tg ,-50 °C elastomers. The chemistry involves copolymerization of α-olefins (i.e. ethylene, propylene, 1-octene, etc.) and p-methylstyrene (p-ms), using metallocene technology. In turn, the p-ms groups in polyolefin are very versatile and can be interconverted to desirable functional groups or produce graft copolymers, such as PE-g-PS, PE-g-PMMA, PP-g-PMMA and EP-g-PMMA. They are very effectively interfacial reagents and can dramatically increase the interaction between polyolefin and other materials, such as nylons, glass and metals.. AB - A new class of polyolefin co- and terpolymers containing ...

Often, cases where complexes have more than 18 valence electrons are attributed to electrostatic forces - the metal attracts ligands to itself to try to counterbalance its positive charge, and the number of electrons it ends up with is unimportant. In the case of the metallocenes, the chelating nature of the cyclopentadienyl ligand stabilizes its bonding to the metal. Somewhat satisfying are the two following observations: cobaltocene is a strong electron donor, readily forming the 18-electron cobaltocenium cation; and nickelocene tends to react with substrates to give 18-electron complexes, e.g. CpNiCl(PR3) and free CpH. In the case of nickelocene, the extra two electrons are in orbitals which are weakly metal-carbon antibonding; this is why it often participates in reactions where the M-C bonds are broken and the electron count of the metal changes to 18.[5]. The 20-electron systems TM(CO)8− (TM = Sc, Y, La) have a cubic (Oh) equilibrium geometry and a singlet (1A1g) electronic ground state. ...

Chemistry of the porphyrins and related compounds is a large and well-established field of research, which includes organic, inorganic, physical, and biochemistry sub-disciplines. The objective of this research will be to continue the groups combined experimental and theoretical approach for the synthesis and detailed characterization of metallocenyl-containing porphyrinoids, and (aza)BODIPYs, which will provide a detailed understanding of factors influencing the metal-metal coupling as well as redox- and photoinduced electron-transfer processes in these systems. Understanding of through-bond and possible though-space interactions between donor (metallocene), antennae (porphyrinoid), and covalently or non-covalently linked acceptor (fullerenes, nanotubes, or graphene) is very important in chemistry and biology and can potentially lead to the fabrication of nanoscale-size functional materials with desired properties in a predetermined modular manner. This research centers on the design, ...

Copolymers of ethylene and alpha olefins that have been formed by the polymerization reaction in the presence of a single site catalyst, such as a metallocene, are used to form collapsible dispensing containers and/or components thereof. Blends of the copolymers with propylene polymers are disclosed and used to form a body wall layer or a collapsible dispensing container head having good bond strength with a body wall layer formed of an ethylene polymer. Methods for improving the adhesion between collapsible dispensing container components, such as between body wall layer formed of an ethylene polymer and another body wall layer formed of a propylene polymer, or between a body wall layer formed of an ethylene polymer and a collapsible dispensing container head formed of a propylene polymer, are also disclosed.

In Co(C5H5)2 the Co centre is sandwiched between two cyclopentadienyl (Cp) rings. The Co-C bond lengths are about 2.1 Å, slightly longer than the Fe-C bond in ferrocene.[3]. Co(C5H5)2 belongs to a group of organometallic compounds called metallocenes or sandwich compounds.[4] Cobaltocene has 19 valence electrons, one more than usually found in organotransition metal complexes such as its very stable relative ferrocene. (See 18-electron rule.) This additional electron occupies an orbital that is antibonding with respect to the Co-C bonds. Consequently, the Co-C distances are slightly longer than the Fe-C bonds in ferrocene. Many chemical reactions of Co(C5H5)2 are characterized by its tendency to lose this extra electron, yielding an 18-electron cation known as cobaltocenium: ...