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111.
IntroductionThegenediagnosistechnology ,alsocallednucleicacidprobetechnology ,hasbecomeanattractivemethodinthefieldsofbiochemistryandclinicalmedicine .Itisprovedtobeconvenientandsafeusingnon radioactivereagentswithelectrochemicalandopticaldetector.Espe c… 相似文献
112.
Lieve A. De Bock Boris Treiger Ludo Van der Auwera René E. Van Grieken 《Mikrochimica acta》1998,128(3-4):191-200
To reveal useful environmental information which is contained in large analytical data sets, an approach, based on the successive application of hierarchical cluster analysis and factor analysis, is proposed. Estimation criteria to determine the most suitable number of clusters and/or factors, are discussed and the interpretation of the cluster and factor analyses results is performed using visual techniques. The data sets were obtained by scanning electron microscope-energy-dispersive X-ray analysis of individual North Sea aerosol particles. 相似文献
113.
Christoph Kratky Heinz Falk Ulrich Zrunek 《Monatshefte für Chemie / Chemical Monthly》1985,116(5):607-623
The molecular and crystal structures of the two racemic diastereomeric 3,4-dihydropyrromethenone derivatives1 and2 of configurations (Z) and (E) were determined at 93 K (1, 2) and at room temperature (1). From an analysis of the crystallographically observed temperature coefficients a pseudorotation flexibility of the pyrrolidinone ring in the crystal is deduced. In both compounds a nearly orthogonal arrangement between the two heterocyclic ring systems is observed, which is ascribed to the steric bulk of the substituents in positions 1 and 3 of the pyrrolidinone ring.Herrn Prof.Josef Schurz zum 60. Geburtstag gewidmet. 相似文献
114.
The complex permittivity for chlorobenzene–alcohol binary mixtures have been determined over the frequency range of 10 MHz to 20 GHz, at 15, 25, 35, and 45°C, using the time-domain reflectometry (TDR) method for 11 concentrations of each chlorobenzene–alcohol system. The alcohols used were methanol, ethanol, and 1-propanol. The values of static dielectric constant, relaxation time, the corresponding excess properties, the Redlich–Kister coefficients up to the third order, the Kirkwood correlation factor, and thermodynamic parameters of the mixtures have been determined. The excess permittivity is found to be negative for chlorobenzene–methanol and chlorobenzene–ethanol, whereas it is positive in the 1-propanol rich region. The excess inverse relaxation time is negative for all the systems studied here. The Kirkwood effective correlation factor increases with an increasing in the molecular size of the alcohol, but decreases with increasing temperature. 相似文献
115.
Ab initio calculations (RHF) of EtX molecules (X=F, Cl, Br, I, or OTs) were carried out with the use of different basis sets. Total
charges on the atoms in the compounds under study were determined by Mulliken's, NPA, and Bader's methods, and a comparison
of these values was performed. For all EtX compounds, a topological analysis of the electron density was carried out within
the framework of Bader's theory, and the global and relative local hardnesses of the above-mentioned ethylating agents were
estimated.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 608–612, April, 1998. 相似文献
116.
刘以训 《中国科学B辑(英文版)》1989,(12)
Several studies indicate that substances synthesized by granulosa cells are capableof regulating oocyte activity. We have studied the effect of factors synthesized by gran-ulosa cells on tPA activity of denuded oocytes using a co- culture system. The resultsshow that an FSH- dependent factor(s) synthesized by granulosa cells (but not by theca-interstitial cells) is capable of stimulating tPA activity of denuded oocytes. This findingis important for understanding hormonal regulation of oocyte tPA activity by mediatorssynthesized in granulosa cells. 相似文献
117.
用包括水抑制作用的动力学方程,根据建立的反应扩散模型和FT合成化学计量关系,计算了工业原颗粒FT合成沉淀Fe/Cu/K催化剂在工业操作条件下的有效因子。根据不同的产物组成,建立了三种化学计量关系式,比较了气相反应和气液反应的有效因子,确立了FT合成沉淀Fe/Cu/K催化剂有效因子的计算方法。在FT合成反应条件下,产物蜡充满了催化剂的微孔,各组分在蜡中的扩散系数要比纯气相中的扩散系数小得多。在工况操作条件下(523K,2.5MPa,500h ̄(-1),尾气循环比3.0),工业原颗粒(d_p=2.5mm,l_p=5~10mm)催化剂的实际有效因子是纯气相反应的一半左右,计算的平均有效因子分别为0.40和0.42。 相似文献
118.
Shortcut method for evaluation and design of a hybrid process for enantioseparations 总被引:1,自引:0,他引:1
Kaspereit M Gedicke K Zahn V Mahoney AW Seidel-Morgenstern A 《Journal of chromatography. A》2005,1092(1):43-54
Hybrid processes for enantioseparations have a considerable potential for reducing investment and operational costs. An example is the combination of simulated moving bed (SMB) chromatography and selective crystallisation. However, the design of integrated processes is a difficult task. A shortcut method is presented that can serve as a tool for design and estimation of the potential of such processes. The approach requires only limited experimental data and thus allows for systematic parameter studies. The method is based on the determination of the purity-performance characteristic of the SMB process and rigorous application of mass balances. The use of relative mass fluxes allows derivation of simple algebraic expressions for essential process parameters. The significant potential of combining SMB and crystallisation is demonstrated for the example of the separation of mandelic acid enantiomers. 相似文献
119.
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
120.
Binary zirconium orthophosphates R1/3Zr2(PO4)3 and M1/4Zr2(PO4)3, where R = Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu; M = Th, U, have been synthesized and studied by IR spectroscopy [structural family of NaZr2(PO4)3 (NZP)]. Vibrational analysis for the PO4 tetrahedron and investigation of symmetry relations among trigonal NZP phases showed that ordering of lanthanide atoms in structures of NaZr2(PO4)3 type with space group R
c leads to symmetry reduced to P
c. The lanthanide atoms occupy the 2b sites. The phosphorus atoms occupy two independent sites: 6f with C
2 symmetry and 12g with C
1 symmetry. Factor group analysis admits that the IR spectrum can contain eight v3 bands and two v1 bands of the stretching vibrations of the PO4 ions. The M atoms of actinides occupy statistical positions in the structure, and space group R
c is retained.Original Russian Text Copyright © 2004 by V. S. Kurazhkovskaya, D. M. Bykov, and A. I. Orlova__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 6, pp. 1013–1019, November–December, 2004. 相似文献