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31.
Unprecedented Efficient Structure Controlled Phosphorescence of Silver(I) Clusters Stabilized by Carba‐closo‐dodecaboranylethynyl Ligands
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Michael Hailmann Natalia Wolf Rebecca Renner Thomas C. Schäfer Benjamin Hupp Dr. Andreas Steffen Prof. Dr. Maik Finze 《Angewandte Chemie (International ed. in English)》2016,55(35):10507-10511
{Ag2(12‐C≡C‐closo‐1‐CB11H11)}n and selected pyridine ligands have been used for the synthesis of photostable AgI clusters that, with one exception, exhibit for AgI compounds unusual room‐temperature phosphorescence. Extraordinarily intense phosphorescence was observed for a distorted pentagonal bipyramidal AgI7 cluster that shows an unprecedented quantum yield of Φ=0.76 for AgI clusters. The luminescence properties correlate with the structures of the central AgIn motifs as shown by comparison of the emission properties of the clusters with different numbers of AgI ions, different charges, and electronically different pyridine ligands. 相似文献
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The eigenvalue analysis of rolling tires is one part of the simulation of tire rolling noise radiation for the reduction of traffic noise. In this paper the general strategies of numerical eigenvalue analysis for nonsymmetric matrices are shown. The special effects observed on rotating bodies are discussed in details. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Gudrun Schürer Peter Gedeck Maik Gottschalk Timothy Clark 《International journal of quantum chemistry》1999,75(1):17-31
The variational method for the calculation of the electronic polarizability of molecules within the NDDO‐based semiempirical MO methods MNDO, AM1, and PM3 was parametrized to improve its accuracy. A training set of 156 compounds was used to fit 34 parameters simultaneously for 12 elements using a simplex optimization. The resulting parameters were tested for a test set of 83 molecules and the calculated polarizabilities compared with the experimental data. For AM1, the RMS deviation between experimental and calculated polarizabilities was reduced from 2.99 (using the original variational treatment) to 0.70 Å3 for the test set and from 2.81 to 0.40 Å3 for the training set. MNDO and PM3 gave similar improvements. ©1999 John Wiley & Sons, Inc. Int J Quant Chem 75: 17–31, 1999 相似文献
36.
Point-of-care testing (POCT) in patients with ischemic heart disease is driven by the time-critical need for fast, specific,
and accurate results to initiate therapy instantly. According to current guidelines, the results of the cardiac marker testing
should be available to the physician within 30 min (“vein-to-brain” time) to initiate therapy within 60–90 min (“door-to-needle”
time) after the patient has arrived at the emergency room or intensive care unit. This article reviews the current efforts
to meet this goal (1) by implementing POCT of established biochemical markers such as cardiac troponins, creatine kinase MB,
and myoglobin, in accelerated diagnosis and management workflow schemes, (2) by improving current POCT methods to obtain more
accurate, more specific, and even faster tests through the integration of optical and electrochemical sensor technology, and
(3) by identifying new markers for the very early and sensitive detection of myocardial ischemia and necrosis. Furthermore,
the specific requirements for cardiac POCT in regard to analytical performance, comparability, and diagnostic sensitivity/specificity
are discussed. For the future, the integration of new immunooptical and electrochemical chip technology might speed up diagnosis
even further. However, every new development will have to meet the stringent method validation criteria set for corresponding
central laboratory testing. 相似文献
37.
Reactions of tris(trifluoromethyl)borane carbonyl, (CF(3))(3)BCO, with ammonia yielded either a mixture of [NH(4)][(CF(3))(3)BC(O)NH(2)], [NH(4)][(CF(3))(3)BCN], and [NH(4)](2)[{(CF(3))(3)BC(O)}(2)NH] or neat [NH(4)](2)[{(CF(3))(3)BC(O)}(2)NH] depending on the reaction conditions. The salt K[(CF(3))(3)BC(O)NH(2)] was obtained as the sole product from the reaction of NH(3) with K[(CF(3))(3)BC(O)F]. A simple synthesis for cyanotris(trifluoromethyl)borates, M[(CF(3))(3)BCN], was developed by dehydration of M[(CF(3))(3)BC(O)NH(2)] (M = [NH(4)], K) using phosgene. In addition, syntheses of the tris(trifluoromethyl)boron species [(CF(3))(3)BC(O)NH(n)()Pr](-), [(CF(3))(3)BC(O)NMe(2)](-), and (CF(3))(3)BC(O)NMe(3), as well as of (CF(3))(3)BC(O)PMe(3), were performed. All species were characterized by multinuclear NMR spectroscopy. As far as neat substances resulted, IR and Raman spectra were recorded and their thermal behaviors were studied by differential scanning calorimetry. The interpretation of reaction pathways, structures, and vibrational spectra are supported by DFT calculations. The solid-state structure of K(2)[{(CF(3))(3)BC(O)}(2)NH].2MeCN was determined by single-crystal X-ray diffraction. 相似文献
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A high-power longitudinally pumped Nd:YAG laser using direct pumping into the upper laser level is demonstrated. With an absorbed pump power of 438 W an output power of 250 W was realized, which results in an optical-to-optical efficiency of 57%. To the best of our knowledge, this is the first demonstration of a high-output power 885 nm pumped laser design. 相似文献
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Eichelbaum M Stösser R Karpov A Dobner CK Rosowski F Trunschke A Schlögl R 《Physical chemistry chemical physics : PCCP》2012,14(3):1302-1312
We have developed a noncontact method to probe the electrical conductivity and complex permittivity of single and polycrystalline samples in a flow-through reactor in the temperature range of 20-500 °C and in various gas atmospheres. The method is based on the microwave cavity perturbation technique and allows the simultaneous measurement of microwave conductivity, permittivity and of the catalytic performance of heterogeneous catalysts without any need for contacting the sample with electrodes. The sensitivity of the method towards changes in bulk properties was proven by the investigation of characteristic first-order phase transitions of the ionic conductor rubidium nitrate in the temperature range between 20 and 320 °C, and by studying the temperature dependence of the complex permittivity and conductivity of a niobium(V)-doped vanadium-phosphorous-oxide catalyst for the selective oxidation of n-butane to maleic anhydride. Simultaneously, the catalytic performance was probed by on line GC analysis of evolving product gases making the technique a real in situ method enabling the noninvasive investigation of electronic structure-function relationships. 相似文献