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81.
Ga8Ir4B – a Gallium Iridium Boride with isolated, nearly square planar Ir4B Groups in a Structure derived from the CaF2 Type The new compound Ga8Ir4B (tetragonal, I41/acd, a = 853.69(2) pm, c = 2 105.69(6) pm, Z = 8, 614 reflections, 31 parameters, R = 0.034) was prepared by reaction of the elements at 1 100°C. The structure is derived from the CaF2 type. It contains isolated Ir4B groups with boron in an unusual, nearly square planar coordination. 相似文献
82.
Bis(diphenylphosphano)alkane- and 1-Diphenylphosphano-2-(2-pyridino)ethane-N-arylsulfinylamine Nickel(0) Complexes Synthesis and properties of the bis(diphenylphosphano)alkane-N-phenyl-sulfinylamine-nickel(0) complexes [Ni{Ph2P(CH2)nPPh2}(PhNSO)] (n = 2 dppe, n = 3 dppp, n = 4 dppb) as well as of the 1-(diphenylphosphano)-2-(2-pyridino)ethane nickel(0) complexes [Ni(dpppe)2], [Ni(dpppe)(p-TolNSO)] and [Ni(dpppe)(PPh3)2] are described. These compounds have been characterized by i. r. and 31P n.m.r. spectroscopy. The N-arylsulfinylamine ligands are η2-(N, S)-side on coordinated. 相似文献
83.
Möller I Thomas A Wingender A Machnik M Schänzer W Thevis M 《European journal of mass spectrometry (Chichester, England)》2012,18(4):407-412
Erythropoietin (EPO) and its recombinant analogues are suspected to be illicitly administered to horses for performance enhancing purposes and, consequently, prohibited in equine sports. Recently, a new erythropoiesis-stimulating agent, peginesatide (Omontys, formerly referred to as Hematide), belonging to the upcoming class of EPO-mimetic peptides, received approval for the treatment of anaemia in humans with chronic kidney disease on dialysis. As the pegylated dimeric peptide of approximately 45 kDa without sequence homology to EPO is not detectable by conventional EPO detection assays, specific methods are bound to be established for horse sports drug testing. Thus, by fortifying equine serum with peginesatide, an approach consisting of a proteolytic digestion with subtilisin after protein precipitation was developed, eventually targeting a proteotypic and xenobiotic pentapeptide which is easily accessible to liquid chromatography- tandem mass spectrometry analysis. The method was validated for qualitative purposes and demonstrated to be specific, precise (relative standard deviations below 14%), sensitive (limit of detection 10 ng mL(-1)) and linear. Being simple, cost-effective and readily transferable to other doping control laboratories, a mass spectrometric assay for the detection of therapeutic concentrations of peginesatide in equine serum is, in terms of preventive doping research, applicable to routine analysis shortly after approval of the drug. 相似文献
84.
Theberge AB Mayot E El Harrak A Kleinschmidt F Huck WT Griffiths AD 《Lab on a chip》2012,12(7):1320-1326
This paper presents a droplet-based microfluidic platform for miniaturized combinatorial synthesis. As a proof of concept, a library of small molecules for early stage drug screening was produced. We present an efficient strategy for producing a 7 × 3 library of potential thrombin inhibitors that can be utilized for other combinatorial synthesis applications. Picolitre droplets containing the first type of reagent (reagents A(1), A(2), …, A(m)) were formed individually in identical microfluidic chips and then stored off chip with the aid of stabilizing surfactants. These droplets were then mixed to form a library of droplets containing reagents A(1-m), each individually compartmentalized, which was reinjected into a second microfluidic chip and combinatorially fused with picolitre droplets containing the second reagent (reagents B(1), B(2), …, B(n)) that were formed on chip. The concept was demonstrated with a three-component Ugi-type reaction involving an amine (reagents A(1-3)), an aldehyde (reagents B(1-7)), and an isocyanide (held constant), to synthesize a library of small molecules with potential thrombin inhibitory activity. Our technique produced 10(6) droplets of each reaction at a rate of 2.3 kHz. Each droplet had a reaction volume of 3.1 pL, at least six orders of magnitude lower than conventional techniques. The droplets can then be divided into aliquots for different downstream screening applications. In addition to medicinal chemistry applications, this combinatorial droplet-based approach holds great potential for other applications that involve sampling large areas of chemical parameter space with minimal reagent consumption; such an approach could be beneficial when optimizing reaction conditions or performing combinatorial reactions aimed at producing novel materials. 相似文献
85.
Markus Follmann Nils Griebenow Michael G. Hahn Ingo Hartung Franz‐Josef Mais Joachim Mittendorf Martina Schfer Hartmut Schirok Johannes‐Peter Stasch Friederike Stoll Alexander Straub Peter Jeschke Ralf Nauen Michael Edmund Beck Hans‐Wilhelm Engels Hans‐Georg Pirkl Reinhard Albers Rolf W. Albach Jens Krause Andreas Hoffmann Holger Casselmann Jeff Dormish 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(36):9503-9503
86.
87.
88.
R. Winkler J. Wilhelm M. Capitelli C. Gorse 《Plasma Chemistry and Plasma Processing》1992,12(1):71-87
Calculations of the electron energy distribution and of relevant macroscopic quantities of collision-dominated, weakly ionized plasmas under rf field action have been performed with increasing degrees of ionization, and the impact of the electron-electron interaction on these quantities was determined. The investigations were performed for the gas plasmas in CO and H2 as representatives of molecular plasmas The energy distribution and macroscopic quantities are obtained by solving the nonstationary Bolizmann equation for a given rf field and degree of ionization taking into accoung and additional Fokker-Planck term besides the collision integrals for the elastic and the main inelastic collision processes. In these molecular plasmas a remarkable impact of the electron-electron interaction connected with increasing Maxwellization is observed for degrees of ionization greater than 10. 相似文献
89.
The solubility of argon in pure liquid water was measured at ca. 100 kPa and from 2 to 40°C using an analytical method characterized by an imprecision of about ±0.05%. From the experimental results, Henry fugacities H
2,1
(T,P
s,1
) (also known as Henry's Law constants or Henry coefficients) at the vapor pressure P
s,1
of water as well as Ostwald coefficients L
2,1
at infinite dilution were obtained. Measurements were made at roughly 0.5°C and/or 1° intervals between 2 and 8°C (region I), and at 5°C intervals above 10°C (region II). A difference plot lnH
2,1
/T suggests an unusual temperature dependence in region I, i.e., between 2 and 8°C. Because of this, the data were treated separately in two parts corresponding to these two regions. Our results are compared with the recent high-precision data of Krause and Benson (Henry fugacities), and with calorimetrically determined quantities (enthalpies and heat capacities of solution). Finally, experimental results are compared with values calculated via scaled particle theory.Communicated in part at the 2nd International Symposium on Solubility Phenomena in Newark, New Jersey, August 12–15, 1986, and at the 4th ISSP in Troy, New York, July 20–August 3, 1990. 相似文献
90.
Mario?ThevisEmail author Andreas?Thomas Wilhelm?Sch?nzer 《Analytical and bioanalytical chemistry》2013,405(30):9655-9667
Urine samples have been the predominant matrix for doping controls for several decades. However, owing to the complementary information provided by blood (as well as serum or plasma and dried blood spots (DBS)), the benefits of its analysis have resulted in continuously increasing appreciation by anti-doping authorities. On the one hand, blood samples allow for the detection of various different methods of blood doping and the abuse of erythropoiesis-stimulating agents (ESAs) via the Athlete Biological Passport; on the other hand, targeted and non-targeted drug detection by means of chromatographic–mass spectrometric methods represents an important tool to increase doping control frequencies out-of-competition and to determine drug concentrations particularly in in-competition scenarios. Moreover, blood analysis seldom requires in-depth knowledge of drug metabolism, and the intact substance rather than potentially unknown or assumed metabolic products can be targeted. In this review, the recent developments in human sports drug testing concerning mass spectrometry-based techniques for qualitative and quantitative analyses of therapeutics and emerging drug candidates are summarized and reviewed. The analytical methods include both low and high molecular mass compounds (e.g., anabolic agents, stimulants, metabolic modulators, peptide hormones, and small interfering RNA (siRNA)) determined from serum, plasma, and DBS using state-of-the-art instrumentation such as liquid chromatography (LC)–high resolution/high accuracy (tandem) mass spectrometry (LC-HRMS), LC–low resolution tandem mass spectrometry (LC-MS/MS), and gas chromatography–mass spectrometry (GC-MS). 相似文献