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111.
Cai H Chen T Wang X Schultz AJ Koetzle TF Xue Z 《Chemical communications (Cambridge, England)》2002,(3):230-231
Reactions of Ta(NMe2)5 with D2SiR'Ph (R' = Me, Ph) were found to give a dideuteride eta 2-imine complex (Me2N)3Ta(mu-D)2(mu-N-eta 2-N,C-CH2NMe)Ta(NMe2)3(1-d2) through C-H activation of an amide ligand via beta-H abstraction, and the structure of 1 was confirmed by single crystal neutron and X-ray diffraction. 相似文献
112.
Thomas F.O. Lim Jerry K. Myers Greg. T. Rogers Paul Ronald Jones 《Journal of organometallic chemistry》1977,135(2):249-259
The regioselectivity of the hydroboration of the methylchlorovinylsilanes, ClnMe3?nSiCHCH2 (n= 0 ? 3), has been investigated using BH3←THF, 9-BBN, disiamyl- and dicyclohexylborane. Methylation of the adducts with methylmagnesium bromide is complicated by formation of tetraalkylboronates. Alkaline hydrogen peroxide oxidation of the boronates gives reasonable yields of the corresponding α- and β-trimethylsilylethanols forn= 0 and 1. Forn= 2 and 3, conversion of the adducts to the corresponding α- and β- deuteroethylsilanes by treatment with excess sodium methoxide in methanol-0-d provides a more effective means of derivatization. Addition of the alkenes,n= 2 or 3, to excess BH3←THF givesca. 90% of the α-boro-organo-chlorosilanes. For all of the alkenes, the dialkylboranes giveca. 80% of the β-boron adducts. 相似文献
113.
6-Diazopenicillanates react with allylic sulphides, selenides and bromides, to give 6,6-disubstituted penicillanates [2,3]-sigmatropic rearrangements. 相似文献
114.
Thomas Armbruster 《Journal of solid state chemistry》1981,36(3):275-288
The phase relations in the system NiOTiO2 were studied between 1000 and 1600°C using quenched powder specimens, DTA runs, and single crystal diffusion couples. Quenching experiments establish the stable phases TiO2 (rutile), NiTiO3 an ilmenite structure type, Ni2(1+x)Ti1?xO4 (x ≥ 0.16), a cation-excess spinel, and Ni1?2xTixO (rocksalt structure type). DTA runs reveal the existence of an additional nonstoichiometric ilmenite phase Ni1?2xTi1+xO3 (x ≤ 0.03) above 1260°C. In quenched (1500, 1450°C) or slowly cooled single crystal diffusion couples, mutual oriented exsolutions occur in the rutile crystal and in the ilmenite diffusion zone. Orientation relations are: {101}rutile{1120}ilmenite; ∥010〉rutile∥00.1〉ilmenite. The cation-excess spinel decomposes below 1375°C into oriented intergrowth of NiTiO3 (ilmenite) and NiO: {111}NiO{0001}NiTiO3; ∥110〉NiO∥21.0〉NiTiO3. 相似文献
115.
The sensitivity of six mammalian cell strains to either germicidal (254 nm) or artificial "solar" simulated radiation was tested. The solar simulator used had an output similar, in some respects, to natural sunlight. Cellular capacity for Herpes simplex virus production was used as the assay procedure. The tested cells were a strain of African green monkey kidney cells and five human skin fibroblast cell strains. The latter included a "normal" cell strain, and four photosensitive cell strains; three of which were strains of xeroderma pigmentosum cells, and one strain of Bloom's syndrome cells. When comparing the D10 values, the different cell strains varied by a factor of six in response to germicidal radiation, but only by a factor of two to artificial "solar" simulated radiation. The relative sensitivity of the cells to either type of radiation also varied from 1.7 to 10.9. Large variations in response occurred even among the xeroderma pigmentosum cell strains. These responses suggest that mammalian cell sensitivity to 254 nm radiation may not be a true indicator of a cell's responses to natural sunlight. 相似文献
116.
Bendazzoli Gianni L. Raimondi Mario Garetz Bruce A. George Thomas F. Morokuma Keiji 《Theoretical chemistry accounts》1977,44(4):341-350
Semiclassical calculations are carried out by two methods for the problem of collision-induced predissociation of electronically excited I2. The first method is that of surface-hopping with the Landau-Zener model. The second method is similar to surface-hopping, except that analytic continuation of the adiabatic potential energy surfaces replaces the Landau-Zener model. Results of the calculations by the two methods compare favorably with each other and with experiment. The possible advantages of the second method are discussed.Camille and Henry Dreyfus Teacher-Scholar, Alfred P. Sloan Research Fellow. 相似文献
117.
118.
Features concerning development, response, selectivity and applications of selective ion-sensitive electrodes are reviewed. Recommendations are made concerning investigations involving the development and applications of electrodes and attention given to the manner of presenting data for publication. 相似文献
119.
Thomas Bally Edwin Haselbach Zuzana Lanyiova Peter Baertschi 《Helvetica chimica acta》1978,61(7):2488-2502
γ-Irradiation of tris (methylidene)-cyclopropane (‘[3]radialene’) 1 in a rigid electron scavenging matrix (butylchoride/i-pentane, 1:1) at 77 K leads to formation of its molecular cation 1 +. Slight softening of the matrix by a temperature increase of 3–5 K results in formation of a newly absorbing species, tentatively assigned arising from structrral relaxation of 1 + by π-bond rotation: 相似文献
120.
Physical methods of molecule observation and manipulation will prove useful, not only as research tools for investigating biomolecular structure and behavior, but also for the creation of nanostructures. Supramolecular and self-assembling structures are able to generate nanostructures, with many such systems being of biological origin. They form the interface between nanotechnology and biotechnology. Whereas biotechnological processes usually involve populations of cells or molecules, nanotechnological methods operate at the level of individual molecule manipulation. This article considers what advances have been made through cross-fertilisation between nanotechnology and biotechnology to develop for the next millennium new analytical tools at the microscale, using nanostructures as the sensitive part and with the ability to detect individual molecules. 相似文献