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71.
Poineau F Johnstone EV Weck PF Forster PM Kim E Czerwinski KR Sattelberger AP 《Inorganic chemistry》2012,51(9):4915-4917
A second polymorph of technetium trichloride, β-TcCl(3), has been identified from the reaction between Tc metal and Cl(2) gas. The structure of β-TcCl(3) consists of infinite layers of edge-sharing octahedra, similar to its MoCl(3) and RuCl(3) analogues. The Tc-Tc distance [2.861(3) ?] between adjacent octahedra is indicative of metal-metal bonding. Earlier theoretical work predicted that β-TcCl(3) is less stable than α-TcCl(3). In agreement with the prediction, β-TcCl(3) slowly transforms into α-TcCl(3) (Tc(3)Cl(9)) over 16 days at 280 °C. 相似文献
72.
73.
74.
Origin of summating potential 总被引:2,自引:0,他引:2
75.
Alverson G Baker WF Ballocchi G Benson R Berg D Blusk S Bromberg C Brown D Carey D Chand T Chandlee C Choudhary BC Chung WH de Barbaro L DeSoi W Dlugosz W Dunlea J Easo S Engels E Faissler W Fanourakis G Ferbel T Garelick D Ginther G Glass G Glaubman M Gutierrez P Hartman K Huston J Johnstone C Kapoor V Kourbanis I Lanaro A Lirakis C Lobkowicz F Lukens P Mani S Maul A Mansour J Miller R Nelson CA Oh B Orris D Pothier E Prebys E Rajaram BM Roser R Ruddick K Shepard PF Shivpuri RK Sinanidis A 《Physical review D: Particles and fields》1994,49(7):3106-3112
76.
The rapid, stereoselective, and specific transfer reduction of alkynes to alkenes using specially-modified, but easily prepared, palladium catalysts is described. Additional use of a phase transfer catalyst in these systems affords a simple method for phase transfer catalysed catalytic transfer reduction which can be carried out in the presence of other potentially reducible functional groups. 相似文献
77.
The thermal lens apparatus as usually designed for energy transfer and thermal conduction studies, has been used to measure the thermal conductivity coefficients of ethylene and ethyl chloride (2.2 × 10?2 and 3.1 × 10?2 J m?1 s?1 K?1). Contrary to previous analyses, a relaxation model based on the IR laser beam diameter must be used in order to get order of magnitude agreement between these data and literature values. The importance of Fresnel diffraction in greatly limiting the accuracy of the above data is determined and it is shown that the traditional design of apparatus is thus wholly unsuitable for a simple qualitative model. A new apparatus design is suggested which is amenable to simple quantitative as well as qualitative interpretation. 相似文献
78.
Hanessian S Margarita R Hall A Johnstone S Tremblay M Parlanti L 《Journal of the American Chemical Society》2002,124(45):13342-13343
The structure and absolute configuration of the marine antithrombotic product dysinosin A was confirmed by total synthesis. The strategy involved disconnections to three subunits, of which two were synthesized from the readily available l-glutamic acid, d-leucine, and d-mannitol. The Grubbs olefin metathesis carbocyclization reaction was utilized to prepare two intermediates. 相似文献
79.
Jennings David A. Petersen James N. Skeen Rodney S. Hooker Brian S. Peyton Brent M. Johnstone Donald L. Yonge David R. 《Applied biochemistry and biotechnology》1995,(1):727-734
The high nutrient concentrations that would exist near the nutrient injection well during the application of cometabolicin situ bioremediation may lead to the development of significant quantities of biomass at this point in the subsurface. This biomass
can decrease the porosity of the soil to such an extent that nutrient injection is no longer possible. In this work, experiments
were conducted using a porous media biofilm reactor, operated under constant substrate loading conditions, such that the pressure
drop across the reactor was allowed to increase to maintain a constant volumetric flow rate through the reactor. Results suggest
that biomass production, and hence biofilm thickness, near the injection feed port is highly sensitive to substrate loading.
In addition, these variations in biofilm thickness produce dramatic differences in the pressure drop that is attained across
the reactor. Use of the Kozeny-Carman equation can be used to predict that once a critical depth has been exceeded, the pressure
drop across the bed will increase exponentially within biofilm depth. This result means that pressure is not a reliable indicator
of the onset of pore plugging. 相似文献
80.