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91.
92.
IntroductionCatal}ticrcactionsaffcctcdb}'diffosionaIlimitationincatal}'stporcshavcbccnextensive1}dcaltx`ithinlit.rat.rcll~5I.Scvcraltcchniqucsonthcspccialcase0fFischcr-Tropschs}'nthcsis(FTS)t\crcapplicdtocxplorcthebchaviorofthiscatal}ticrcactionundercxpcrimcntalandopcrationaIconditionsI3~5l.It`"ouldbeofvaluctoindicatchcrcthatthcseinvcstigationsx"ercmainl}'bascdonthesimplcstkineticsofthcfirstordcrinH2proposedbyAndersonl6]attheearIystages.However-thesetboents,striCtlyspeaking,areinvalidfor… 相似文献
93.
Wolfgang Hnle Walter Schmettow Karl Peters Jen‐Hui Chang Hans Georg von Schnering 《无机化学与普通化学杂志》2004,630(12):1858-1862
The novel ternary polyphosphides M4P21I (M = K, Rb) have been synthesized from the elements in single crystalline form, representing further examples for the formation of mixed crystals between simple salts and binary phosphides. They form as ruby‐red platelets and dark‐red prisms, respectively, and are only slightly sensitive to moisture and oxygen. The compounds are isotypic (Ccmm (no 63); Z = 4; oP104; K4P21I: a = 12.853Å; b = 21.795Å; c = 9.748Å; 1168 hkl, R = 0.033; Rb4P21I: a = 13.281Å; b = 21.868Å; c = 9.771Å; 777 hkl, R = 0.053) and feature corrugated 2D networks formed from two different types of polymerized P7 units. The networks form large cavities filled by M+ and I‐ ions. Zigzag chains of condensed trigonal M6 prisms, centered by the I‐ anions, separate the polyphosphide nets. The mean homoatomic P‐P bond length (d = 2.216Å) corresponds to a P‐P single bond. However, the individual P‐P distances vary with position and function (2.126 ‐ 2.247Å) and these are compared with those of the isolated P21‐3 anion. 相似文献
94.
M. Nève de Mévergnies 《Applied Physics A: Materials Science & Processing》1981,25(3):275-282
The multiphoton dissociation of CF3Cl induced by TEA-CO2 laser pulses has been studied in a focused beam geometry. TheR(10) [00°1–02°0] (
) laser line was used, so as to dissociate preferentially the minor isotopic component13CF3Cl. The isotopic selectivityS and the dissociation probability per pulse ω were measured in the pressure range between 0.25 and 8 Torr. With short laser
pulses (90 ns FWHM),S is found to increase slightly with gas pressure up to 2 Torr, and ω, to increase almost linearly over the whole pressure
range studied. A schematic model is proposed which satisfactorily explains these results if the transition rates across the
energy level spectrum of the CF3Cl molecules are assumed to increase with gas pressure. 相似文献
95.
Osvaldo Marrero 《Aequationes Mathematicae》1977,16(3):195-220
This work is an attempt to give a complete survey of all known results about pseudo (v, k, )-designs. In doing this, the author hopes to bring more attention to his conjecture given in Section 6; an affirmative answer to this conjecture would settle completely the existence and construction problem for a pseudo (v, k, )-design in terms of the existence of an appropriate (v, k, )-design. 相似文献
96.
Frank J.S. Wang 《Stochastic Processes and their Applications》1977,5(2):173-193
Consider a population consisting of one type of individual living in a fixed region with area A. In [8], we constructed a stochastic population model in which the death rate is affected by the age of the individual and the birth rate is affected by the population density PA(t), i.e., the population size divided by the area A of the given region. In [8], we proposed a continuous deterministic model which in general is a nonlinear Volterra type integral equation and proved that under appropriate conditions the sequence PA(t) would converge to the solution P(t) of our integral equation in the sense that .In this paper, we obtain a “central limit theorem” for the random element √A(PA(t)?P(t)). We prove that under appropriate conditions √A(PA(t)?P(t)) will converge to a Gaussian process. (See Theorem 3.4 for the explicit formula of this Gaussian process.) 相似文献
97.
单扫描极谱法测定注射液及血清中维生素K1 总被引:5,自引:0,他引:5
建立了维生素K1的极谱测定方法.在0.05 mol·L-1 NH4Cl-NH3(pH 8.58)缓冲溶液中,维生素K1可产生一极谱还原峰,峰电位Ep为-0.39 V ;其二阶微分峰峰电流ip″与维生素K1的浓度在1.1×10-7 ~2.2×10-5 mol·L-1范围内呈线性关系,相关系数r=0.998 6(n= 9 );方法的检出限为4.0×10-8 mol·L-1.13次平行测定2.2×10-5 mol·L-1维生素K1还原波二阶导数峰峰电流ip″的相对标准偏差(RSD)为1.83%.本法可直接用于注射液及血清中维生素K1含量的测定. 相似文献
98.
99.
A flow injection method combined with Resonance light scattering detection was developed for the determination of protein
concentration in human serum samples. This method is based on the enhanced RLS signals of protein binding with the dye acid
chrome blue K. The enhanced RLS intensities at 264 nm, in an acidic aqueous solution, were proportional to the protein concentration
over the range of 2.0–40.0 μg·mL−1 for human serum albumin (HSA) and the limit of detection (3σ) is 85 ng·mL−1. This method was successfully applied to the quantification of total proteins in human serum samples. The maximum relative
standard deviation is less than 2% and the recovery is between 97 and 103% for the standard addition method. The sample throughput
was 60 h−1. 相似文献
100.
The Zimmermann reaction for the determination of 17-ketosteroids was tested under both room-temperature and steam-distillation reaction conditions. meta-Nitroaniline was isolated from the residue of the steam distillation by ether extraction and thin-layer chromatography. Conclusive identification was by infrared spectroscopy. In contrast, m-nitroaniline was not formed under room-temperature reaction conditions, even when allowed to react for 24 hr. Similar results were also obtained for the reaction between acetone and m-dinitrobenzene under alkaline conditions. In conclusion, the results indicate that m-nitroaniline formation cannot account for the conversion of structure I to structure II under room-temperature reaction conditions as investigated herein. 相似文献