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101.
新颍Mo-Cu-Se簇合物{MoCu3Se3I}(PPh3)3O·0.5CH2Cl2是由[Et4N]2MoSe4、Cu(PPh3)2NO3和KI在乙腈和二氯甲烷1∶1的混合溶剂中反应所得。晶体属单斜晶系,空间群P21相似文献   
102.
The concept of the residence time τksp of an atom in a kink site has recently been suggested to understand the processes in electrochemical deposition of alloys and intermetallic compounds. Different kink sites with different residence times must be defined for alloys and intermetallic compounds. Based on this model, the finite Markov chain theory is applied to describe the selectivity of the growth process. An analytical relationship between the alloy composition and the metal ion concentrations in the electrolyte is derived. General model parameters are ratios g i = K ii/K ij of equilibrium constants of the reaction of electrolyte ions with different kink sites on the surface (i, j representing different alloy components). These ratios are called selectivity constants. For simple conditions, the equation g i ≈ τiiij connects the g i values with the residence times. The theory is tested in the deposition of alloys Co-Ni (anomalous co-deposition) and Ni-Mo (induced co-deposition). Additionally, Bi2Te3, an example of stoichiometric semiconductor deposition, is treated. Published in Russian in Elektrokhimiya, 2006, Vol. 42, No. 10, pp. 1216–1223. The text was submitted by the authors in English.  相似文献   
103.
研究了用毛细管区带电泳法快速测定复方布洛芬片中布洛芬和伪麻黄碱含量的方法。在0.025mol/L的磷酸盐缓冲液(pH8.1)中,上述两组分可在3min内得以完全分离,用紫外检测器在210nm处检测,并以外标法定量。11次测定含有9.5mg/L盐酸伪麻黄碱和66.7mg/L布洛芬的试样溶液,相对标准偏差为2.9%(伪麻黄碱)和1.9%(布洛芬),回收率为103.1%(伪麻黄碱)和97.6%(布洛芬)。应用毛细管区带电泳法测定复方布洛芬片剂的含量,所得结果与HPLC法一致。  相似文献   
104.
用一简单的相关函数式对金属间化合物的热力学性质进行拟合,提出了一种计算金属间化合物热力学性质的新方法,并用此方法计算了二元金属间化合物的常温热容和熵。计算结果表明,该方法简单,且能满足一定的计算精度,有一定的实用价值。  相似文献   
105.
Two new alkaline-earth Nd selenite chlorides MNd10(SeO3)12Cl8 (M=Ca, Sr) were obtained using crystal growth from alkaline-earth chloride melts in quartz tubes. These new compounds crystallize in the orthorhombic system in space group C cca (#68). The compounds were studied by energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction. It was shown that both compounds adopt the same structure type, constructed by complex [M11(SeO3)12]8+ slabs separated by chloride anion layers perpendicular to the longest cell parameter. The SeO3 groups show a pyramidal shape and may be described as SeO3E tetrahedra. Such SeO3 groups decorate the Nd-O skeletons forming the [M11(SeO3)12]8+ slabs.  相似文献   
106.
翟纬绪  赵转云 《有机化学》1986,6(2):134-138
Pt(PPh_3)_2Cl_2在碱性介质中,与一氧化碳直接进行还原及羰基化反应,得到五种膦取代的羰基铂配合物:Pt_5(μ_2-CO)_5(CO)(PPh_3)_4 1,Pt_3(μ_2-CO)_3(PPh_3)_3 2,Pt_3(μ_2-CO)_3(PPh_3)_4 3,Pt_4(μ_2-CO)_5(PPh_3)_4 4,以及Pt(Cl)(PPh_3)_2(COOCH_3) 5。经X-射线单晶衍射分析,确定了新的三核铂羰基簇2以及配合物5的分子结构。还讨论了1和5的生成机理。  相似文献   
107.
用硒与尿素化合,新生的由杂环有机硒所组成的Zs-93硒剂治疗移植性S180肉瘤,有显著的抑瘤作用(P<0.01),其作用表现出一定的剂量效应,以5μg/只小鼠为最适,抑瘤率达60.76%,治疗组小鼠的T细胞、SOD活性均有增强。  相似文献   
108.
Summary The purity of the investigational antibacterial Abbott-086719.1 (I) which is 8[(3S)-3-amino-1-pyrrolidinyl]-1-cyclopropyl-7-fluoro-9-methyl-4-oxo-4H-quinolizine-3-carboxylic acid hydrochloride is determined using gradient elution HPLC. The chromatographic separation was optimized and the chromatographic parameters critical to separation are discussed in detail. Most acceptable separations were achieved using an Alltima C18 column (5 m) measuring 4.6 mm I.D.×15 cm with 0.01M–0.03M citrate eluents which were modified with acetonitrile or with mixtures of acetonitrile and methanol. Related substances in I were determinable to 0.05%. Repeatability (RSD values) for determining related substances at levels of 0.50 to 0.06% ranged from ±1.9 to ±10%. Determinations of I in 5% dextrose in water and in hydroxypropyl methylcellulose were made using the same column and a simple isocratic system. The determination of I was stability indicating with precision (RSD values) of ±0.5% to ±2.0% and good agreement with theory for formulations containing I at 1.0 to 95 mg/mL concentrations. Recoveries of I from the vehicles were quantitative and linearity of the detector response of I was demonstrated to at least 0.10 mg/mL.  相似文献   
109.
The crystal structure of thiamine iodide sesquihydrate has been determined by X-ray diffraction methods as a host-guest model for coenzyme-substrate interactions. The asymmetric unit contains two chemical units. Both the thiamine molecules A and B, which are crystallographically independent, assume the usualF conformation and have a disordered hydroxyethyl side chain. An iodide anion (or a water molecule) bridges the pyrimidine and thiazolium rings of molecule A (or B) by forming a hydrogen bond with the amino group and an electrostatic contact with the thiazolium ring to stabilize the molecular conformation. In the crystal the thiamine molecules self-associate to form a pipe-like polymeric structure, in which four thiamine hosts surround an iodide guest and hold it through C(2)-H...I hydrogen bonds and thiazolium...I electrostatic interactions. Crystal data: C12H17N4OS+·I · 1.5 H2O, monoclinic,P21/c, a=12.585(2), b=25.303(5), c=12.030(2) Å, =115.15(1)°,V=3468(1) Å3,Z=8,D c=1.606 g cm–3,R=0.045 for 3328 observed reflections. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP. 82156 (13 pages).  相似文献   
110.
Preparation of cellulose and cellulose derivative azo compounds   总被引:1,自引:0,他引:1  
Wood pulp and cotton linter are the most common sources of cellulose forindustrial use. Methyl cellulose (MC) and cellulose sulfate (CS) were preparedusing bleached wood pulp and cotton linter. Coloured azo compounds were alsoprepared from coupling cellulose, wood pulp, MC and CS with aromatic diazoniumsalt. The presence of electron-releasing or withdrawing substituents affectedthe electrophilic substitution reaction. The produced azo compounds werecharacterized by FT-IR methodology, as well as mass spectrometry, in which thefunctional groups and the ion fragments of the products were analyzed.  相似文献   
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