نتایج جستجو برای: metallocene catalyst
تعداد نتایج: 44388 فیلتر نتایج به سال:
The uranium bipyridyl metallocene, [η5-1,2,4-(Me3C)3C5H2]2U(bipy) (2), prepared from [η5-1,2,4-(Me3C)3C5H2]2UCl2 (1) and 2,2′-bipyridine in the presence of potassium graphite (KC8) has been evaluated small-molecule activation. In contact with AgF, Ph2E2 (E = S, Se), (PhNH)2, (PhCH═N)2, diazenes, pyridine N-oxide, organic azides, diazoalkanes, Ph2CS, Ph2CO, it behaves as a synthon for [η5-1,2,4-...
We analyze a new family of carbon nanotube-based molecular wires, formed by encapsulating metallocene molecules inside the nanotubes. Our simulations, which are based on a combination of nonequilibrium Green function techniques and density functional theory, indicate that these wires can be engineered to exhibit desirable magnetotransport effects for use in spintronics devices. The proposed str...
This account critically surveys the field of side-chain transition metal-containing polymers as prepared by controlled living ring-opening metathesis polymerization (ROMP) of the respective metal-incorporating monomers. Ferrocene- and other metallocene-modified polymers, macromolecules including metal-carbonyl complexes, polymers tethering early or late transition metal complexes, etc. are here...
Two different hybrid cavitand-resorcin[4]arenes are shown to be effective and selective receptors for the molecular inclusion of positively charged organometallic sandwich complexes of appropriate size. The binding constants of the 1 : 1 complexes formed with a series of neutral and positively charged metallocenes have been calculated using different titration techniques. The motion of the incl...
B. Anionic Ligands 302 IX. Group 9 Catalysts 302 X. Group 10 Catalysts 303 A. Neutral Ligands 303 1. R-Diimine and Related Ligands 303 2. Other Neutral Nitrogen-Based Ligands 304 3. Chelating Phosphorus-Based Ligands 304 B. Monoanionic Ligands 305 1. [PO] Chelates 305 2. [NO] Chelates 306 3. Other Monoanionic Ligands 306 4. Carbon-Based Ligands 306 XI. Group 11 Catalysts 307 XII. Group 12 Catal...
A series of seven new complexes of zirconium and hafnium with bulky ω-aryloxyalkyl substituted indenyl ligands were synthesized and characterized by NMR spectroscopy and elemental analysis. These complexes were activated with methylaluminoxane and tested for homogeneous ethylene polymerization. The zirconium catalysts showed higher activities than their hafnium an...
Aqueous biphasic catalysis is a convenient approach to convert organic, partially soluble molecules in water. However, converting more hydrophobic substrates is much more challenging as their solubility in water is extremely low. During the past ten years, substantial progress has been made towards improving the contact between hydrophobic substrates and a hydrophilic transition-metal catalyst....
This paper argues that Information Technology (IT) needs to be demystified, through critical consciousness, for educators to focus on IT as a means to enhance learning. It goes on to define the technical, sociohistorical and political-ideological levels of IT and to identify four theoretical constructs: tutorial, machine-as-human, tool kit and catalyst. Pervading these constructs is the underst...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید