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51.
周代梅  萨本豪  陆中道  蔡勖 《中国物理 C》2002,26(10):1072-1077
用强子–弦级联模型JPCIAE及相应的Monte Carlo事例产生器研究相对论性核–核碰撞中带电粒子多重数的赝快度密度对能量和中心度的依赖关系.无需另调任何模型参数的条件下,此模型可以同时较好地描述相对论性pp实验数据及PHOBOS和PHENIX实验组的Au+Au实验数据.本文指出:因〈Npart〉并非严格定义的物理量,致使实验上和理论上确定〈Npart〉有一定任意性,从而使得每参加者核子对的带电粒子赝快度密度随着〈Npart〉的增加可能逐渐增大,也可能逐渐减小,因此用它来区分粒子产生机制是欠妥的.  相似文献   
52.
The result of the calculation of the field of a longitudinal wave which has passed through an elastic layer is studied and the character of the propagation of different phases of this wave is determined.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im V. A. Steklova AN SSSR, Vol. 165, pp. 159–165, 1987.  相似文献   
53.
Journal of Analytical Chemistry - Silver nanoparticles modified with Eu3+ ions increase the intensity of the fluorescence signal by a factor of 125 in an analytical system containing doxycycline as...  相似文献   
54.
Transition Metal Chemistry - In this study, Ni(II) and Co(II) complexes [Co(H2O)2L2] (1), [Ni(H2O)2L2] (2), [Co(phen)L2] (3), [Ni(phen)L2]·2H2O·EtOH (4·2H2O), and...  相似文献   
55.
The sensitive BRET system for the homogeneous immunoassay of a low‐molecular weight antigen was developed using progesterone as an example. Two thermostable mutants of the Luciola mingrelica firefly luciferase (Luc)—the “red” mutant with λmax.em = 590 nm (RedLuc) and the “green” mutant with λmax.em = 550 nm (GreenLuc)—were tested as the donors. The water‐soluble Alexa Fluor 610× (AF) dye was selected as the acceptor because its two absorption maxima, located at 550 and 610 nm, are close to the bioluminescence maxima of the GreenLuc and RedLuc, respectively. The methods for the synthesis of the luciferase–progesterone (Luc–Pg) conjugate and the conjugate of the dye and the polyclonal antiprogesterone antibody (AF–Ab) were developed. Both conjugates retained their functional properties, had high antigen–antibody binding activity, and demonstrated a high BRET signal. The homogeneous immunoassay system based on the BRET from the firefly luciferase to the synthetic dye was established to assay progesterone as a model antigen. Optimization of the assay conditions, the composition of the reaction mixture, and the concentrations of the donor and the acceptor made it possible to reach the minimum detectable progesterone concentration of 0.5 ng mL?1.  相似文献   
56.
The heats of dissolution of benzene, chlorobenzene, ortho-dichlorobenzene, nitrobenzene, and aniline in n-hexane and 1-butanol and those of benzene, chlorobenzene, nitrobenzene, and aniline in a mixture of n-hexane and 1-butanol were measured by calorimetry at 25°C. The enthalpies of solvation of the compounds were calculated. The correlation between the enthalpies of solvation of the compounds and their molar refraction was studied. The enthalpies of solvation of the compounds and their functional groups by the mixture of n-hexane and 1-butanol were considered.  相似文献   
57.
The 950°C isothermal section of the InPO4-Na3PO4-Li3PO4 ternary system was studied and constructed; one-, two, and three-phase fields are outlined. Five solid-solution regions exist in the system: solid solutions based on the complex phosphate LiNa5(PO4)2 (olympite structure), the indium ion stabilized high-temperature Na3PO4 phase (Na3(1 − x)In x (PO4); space group Fm [`3]\bar 3 m), the complex phosphate Na3In2(PO4)3, and the α and β phases of the compound Li3In2(PO4)3. A narrow region of melt was found in the vicinity of eutectic equilibria. All the phases detected in the system are derivatives of phases existing in the binary subsystems. Isovalent substitution of lithium for sodium in Na3In2(PO4)3 leads to a significant increase in the region of a NASICON-like solid solution.  相似文献   
58.
Tri(m-tolyl)antimony bis(1-adamantanecarboxylate) (3-MeC6H4)3Sb[OC(O)C10H15]2 has been synthesized with a yield of 90.0% by the reaction of tri(m-tolyl)antimony with 1-adamantanecarboxylic acid in the presence of hydrogen peroxide in ether. According to X-ray diffraction analysis data, the antimony atom has a distorted trigonal-bipyramidal coordination with the axially positioned oxygen atoms of carboxyl groups. The axial OSbO angle is 173.1(2)°; the equatorial CSbC angles are 112.0(1)°, 112.0(1)°, and 136.0(3)°; the Sb-O distance is 2.109(3)Å; the Sb-C distances are 2.103(5), 2.103(5), and 2.121(7) Å; intramolecular Sb…O(=C) contacts are 3.069(5) Å.  相似文献   
59.
Using the aggregation numbers of micelles and the effective sizes of hydrated surfactant ions and counterions of the first coordination sphere, we calculated the average geometric characteristics of the surface layer of ionic spherical micelles in solutions of the sodium n-alkyl sulfate homologues with n C = 8, 10, 12, and 14 carbon atoms in the molecule; in particular, we established 1) the size of the micelle core; 2) the thickness of the electrical double layer on the surface; 3) the mutual arrangement parameters of hydrophilic and hydrophobic ions; 4) the number of “free” water molecules and showed their dependence on the homologue number and the degree of binding of counterions.  相似文献   
60.
The structure of Ga2O3–Al2O3 supports and Pd/Ga2O3–Al2O3 catalysts and the performance of these catalysts in liquid-phase acetylene hydrogenation have been investigated. The deposition of Ga(NO3)3 onto Al2O3 by impregnation followed by calcination of the impregnated support at 600°C yields γ-Ga2O3–Al2O3 solid solutions containing up to 50 wt % Ga2O3. X-ray diffraction characterization of model palladium catalysts and their temperature-programmed reduction with hydrogen have demonstrated that, while palladium in Pd/Ga2O3 is in the form of a Pd2Ga alloy, in the Pd/γ-Ga2O3–Al2O3 catalyst there is no direct interaction between PdО and Ga2O3 particles and palladium is in the monometallic state. The introduction of 10–20 wt % gallium oxide into Al2O3 lowers the activity of the supported palladium catalyst relative to that of the initial Pd/Al2O3 but increases the ethylene yield by enhancing the ethylene formation selectivity.  相似文献   
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