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961.
Stefan Scholz Michael Bolte Matthias Wagner Hans‐Wolfram Lerner Dr. 《无机化学与普通化学杂志》2007,633(8):1199-1204
Syntheses and Properties of Di‐tert‐butylphosphides [M(PtBu2)2]2 (M = Zn, Hg) and [Cu(PtBu2)]4 The phosphides [M(PtBu2)2]2 (M = Zn, Hg) and [Cu(PtBu2)]4 are accessible from reaction of LiPtBu2 with ZnI2, HgCl2 and CuCl, respectively. [M(PtBu2)2]2 (M = Zn, Hg) are dimers in the solid state. X‐ray structural analyses of these phosphides reveal that [M(PtBu2)2]2 (M = Zn, Hg) contain four‐membered M2P2‐rings whereas [Cu(PtBu2)]4 features a planar eight‐membered Cu4P4‐ring. Degradation reaction of LiPtBu2(BH3) in the presence of HgCl2 results in the dimeric phosphanylborane BH3 adduct [tBu2PBH2(BH3)]2. X‐ray quality crystals of [tBu2PBH2(BH3)]2 (monoclinic, P21/n) are obtained from a pentane solution at 6 °C. According to the result of the X‐ray structural analysis, the O2‐oxidation product of [Hg(PtBu2)2]2, [Hg{OP(O)(tBu)OPtBu2}(μ‐OPtBu)]2, features in the solid state structure two five‐membered HgP2O2‐rings and a six‐membered Hg2P2O2‐ring. Herein the spiro‐connected Hg atoms are member of one five‐membered and of the six‐membered ring. 相似文献
962.
ISO radiation sterilization standards 总被引:2,自引:0,他引:2
This presentation provides an overview of the current status of the ISO radiation sterilization standards. The ISO standards are voluntary standards which detail both the validation and routine control of the sterilization process. ISO 11137 was approved in 1994 and published in 1995. When reviewing the standard you will note that less than 20% of the standard is devoted to requirements and the remainder is guidance on how to comply with the requirements.
Future standards developments in radiation sterilization are being focused on providing additional guidance. The guidance that is currently provided in informative annexes of ISO 11137 includes: device/packaging materials, dose setting methods, and dosimeters and dose measurement, currently, there are four Technical Reports being developed to provide additional guidance:
- 1. 1. AAMI Draft TIR, “Radiation Sterilization Material Qualification”
- 2. 2. ISO TR 13409-1996, “Sterilization of health care products — Radiation sterilization — Substantiation of 25 kGy as a sterilization dose for small or infrequent production batches”
- 3. 3. ISO Draft TR, “Sterilization of health care products — Radiation sterilization Selection of a sterilization dose for a single production batch” li]4. ISO Draft TR, “Sterilization of health care products — Radiation sterilization-Product Families, Plans for Sampling and Frequency of Dose Audits.”
963.
Mary E. R. McHale Joyce R. Powell Ann-Sofi M. Kauppila William E. Acree Jr. Pierre L. Huyskens 《Journal of solution chemistry》1996,25(11):1089-1104
Experimental solubilities are reported for anthracene dissolved in eight binary mixtures containing 2-ethoxyethanol with 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 1-pentanol, 3-methyl-1-butanol and 1-octanol, and also in binary 1-pentanol+2-methoxyethanol and 2-methyl-1-propanol+2-propoxyethanol solvent systems at 25°C. Results of these measurements, combined with previously reported anthracene solubility data in 22 different alcohol +2-alkoxyethanol (2-methoxyethanol, 2-propoxyethanol and 2-butoxyethanol) solvent mixtures, are used to test the limitations and applications of expressions derived from Mobile Order theory. The first predictive expression assumes only formation of homogeneous self-associated hydrogen-bonded species, whereas the second equation includes additional terms to account for heterogeneous complex formation between the dissolved alcohol and 2-alkoxyethanol solvent molecules. Both equations predict the observed anthracene solubilities to within an average absolute deviation of about 3%. 相似文献
964.
Voltammetric determination of copper and lead in gasoline using sample preparation as microemulsions. 总被引:1,自引:0,他引:1
Carlos E Cardoso Wagner F Pacheco Rangel Sarubi Márcio L N Ribeiro Pércio A M Farias Ricardo Q Aucélio 《Analytical sciences》2007,23(9):1065-1069
A voltammetric method for the determination of Cu(II) and Pb(II) in gasoline using sample preparation as three-component solutions (gasoline:propan-1-ol:water, 25:60:15 v/v/v) is proposed. HNO(3) was employed as a supporting electrolyte and to allow the use of aqueous inorganic standards for calibration, even if the analyte species originally in gasoline is present as a metallo-organic form. A square-wave anodic sequential determination was used by measuring the stripping current of Cu(II) (at +104 mV) using a glassy carbon electrode (GCE) and, in a second run, measuring the Pb(II) stripping current (at -470 mV) using a bismuth-film deposited on the surface of the GCE. The method allowed the quantification of 1.7 x 10(-9) mol L(-1) of Cu and 1.4 x 10(-10) mol L(-1) of Pb employing a 1500-s accumulation time. Recovery tests using analyte spiked three-component solutions prepared with commercial gasoline samples enabled recoveries of Cu and Pb from 97 +/- 8 to 102 +/- 5%. 相似文献
965.
A novel approach for characterizing protein ligand complexes: molecular basis for specificity of small-molecule Bcl-2 inhibitors 总被引:5,自引:0,他引:5
Lugovskoy AA Degterev AI Fahmy AF Zhou P Gross JD Yuan J Wagner G 《Journal of the American Chemical Society》2002,124(7):1234-1240
The increasing diversity of small molecule libraries has been an important source for the development of new drugs and, more recently, for unraveling the mechanisms of cellular events-a process termed chemical genetics.(1) Unfortunately, the majority of currently available compounds are mechanism-based enzyme inhibitors, whereas most of cellular activity regulation proceeds on the level of protein-protein interactions. Hence, the development of small molecule inhibitors of protein-protein interactions is important. When screening compound libraries, low-micromolar inhibitors of protein interactions can be routinely found. The enhancement of affinities and rationalization of the binding mechanism require structural information about the protein-ligand complexes. Crystallization of low-affinity complexes is difficult, and their NMR analysis suffers from exchange broadening, which limits the number of obtainable intermolecular constraints. Here we present a novel method of ligand validation and optimization, which is based on the combination of structural and computational approaches. We successfully used this method to analyze the basis for structure-activity relationships of previously selected (2) small molecule inhibitors of the antiapoptotic protein Bcl-xL and identified new members of this inhibitor family. 相似文献
966.
In topological linear spaces convex hulls of bounded sets are, in general, not bounded. The question arises whether there is at least for every bounded set B a sequence {|} of strictly positive numbers such that the set {
l
n
v
B|n} is bounded. When this obtains, bounded sets share several of the properties known in locally convex spaces. The main result of this note is an example of a countable inductive limit of complete metrizable topological linear spaces which is neither regular nor sequentially complete and also fails to have the above bounded summability property. 相似文献
967.
W. Bartel P. Duinker J. Olsson P. Steffen J. Heintze G. Heinzelmann R.D. Heuer R. Mundhenke H. Rieseberg B. Schürlein A. Wagner A.H. Walenta 《Physics letters. [Part B]》1976,64(4):483-487
Decays of the J/ψ (3.1) resonance into final states with two charged hadrons and two photons are investigated. Branching ratios for the decays J/ψ → ?π and J/ψ → γη′ are determined to be Upper limits for the same decay modes of ψ′ (3.7) are also determined. 相似文献
968.
969.
Klein SR Himel T Abrams G Amidei D Baden AR Barklow T Boyarski AM Boyer J Burchat PR Burke DL Butler F Dorfan JM Feldman GJ Gidal G Gladney L Gold MS Goldhaber G Haggerty J Hanson G Hayes K Herrup D Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Karlen D Lankford AJ Larsen RR LeClaire BW Levi M Lockyer NS Lüth V Nelson ME Ong RA Perl ML Richter B Riles K Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH de la Vaissiere C Wagner SR Wood DR Yelton JM 《Physical review letters》1989,62(21):2444-2447
970.