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61.
New invariant tests of normality based on Shepp property are constructed and studied. Test statistics are functions of a U-empirical process. The limiting distributions and large deviations of test statistics under the null-hypothesis are described. Local Bahadur efficiency of new tests is calculated under simplest parametric alternatives (shift, skew, and contamination alternatives). 相似文献
62.
Salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides, RCH(OH)CH2N(O)=NO− M+ (R=Me, Pri, or But; and M=Li, Na, K, Ag, NH4, or Me4N), were prepared. Their alkylation with alkyl halides R′X (X=Cl, Br, or I) and dimethyl sulfate was studied. Generally, alkylation
afforded mixtures ofN-(β-hydroxyalkyl)-N′-alkoxydiazeneN-oxides RCH(OH)CH2N(O)=NOR′ andO-alkyl-N-(β-hydroxyalkyl)-N-nitrosohydroxylamines RCH(OH)CH2N(NO)OR′.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1996–2001, October, 1998. 相似文献
63.
Oleksii M. Antypenko Sergiy I. Kovalenko Oleksandr V. Karpenko Vladyslav O. Nikitin Lyudmyla M. Antypenko 《Helvetica chimica acta》2016,99(8):621-631
Considering the frightening high level of mortality from cancer, studies of anticancer agents are vital nowadays. The 24 thioderivatives of 2‐alkyl(aryl)‐quinazolin‐4(3H)‐thiones and 20 thioderivatives of [1,2,4]triazolo[1,5‐c]quinazoline‐2‐thiones were synthesized and evaluated for preliminary in vitro anticancer activity with subsequent in silico QSAR analysis. The substance 18 had the best results inhibiting growth of eight cancer cell lines: CCRF‐CEM of leukemia; SF‐539, SNB‐75, and U251 of CNS cancer; 786, RXF393, and UO‐31 of renal cancer; and MDA‐MB‐231/ATCC of breast cancer (?31.50 – 47.41% of cell growth) with low procancer effect. Calculated QSAR‐models for CCRF‐CEM of leukemia, T‐47D and HS 578T of breast cancer, and mean cell growth demonstrated good rate of anticancer activity prediction (r2 = 0.7 – 0.8, = 0.5 – 0.7). 相似文献
64.
高效液相色谱法测定兔肉中氯羟吡啶 总被引:3,自引:0,他引:3
球虫病是畜禽业养殖过程中的重要疾病之一,不有效地加以控制会给广大养殖户造成很大的经济损失。氯羟吡啶由于其较强的抗球虫病作用而在畜禽养殖业中得到广泛应用。但是,长期使用或不按规定用药会造成氯羟吡啶在动物体内和组织中残留,对环境及公众健康构成严重的潜在危害。现在,欧盟、美国等发达国家及中国、中国台湾都规定了各种动物组织中氯羟吡啶残留最高限量标准。组织中氯羟吡啶的检测方法主要采用气相色谱法(GC)[1]、高效液相色谱法(HPLC)[2]和气相色谱-质谱联用法(GC-MS)[3]等。HPLC具有简便快速、灵敏的特点,成为分析组织中氯… 相似文献
65.
阴离子分散剂对酸化膨润土流变性的影响 总被引:1,自引:0,他引:1
研究了阴离子分散剂聚丙烯酸钠对质量分数为10%的酸化膨润土分散体系流变性的影响. 结果表明, 添加0.4%分散剂的分散体系的剪切应力、表观黏度和屈服应力最低. 其它体系流体均表现为从假塑型到胀流型流体的转变, 而含0.4%分散剂的体系始终表现为胀流型流体. 采用Herschel-Bulkley模型对各体系的流变曲线进行了拟合, 得到较好的拟合曲线, 同时探讨了酸化膨润土分散体系的流变机理. 相似文献
66.
敬钊毒素-I(JZTX-I)是一种能够抑制心肌钠通道失活的新型蜘蛛神经毒素,该文结合高效液相色谱与色氨酸荧光测定技术研究了JZTX-I的磷脂膜结合活性。脂质体共沉淀实验表明,JZTX-I具有不依赖于带负电荷磷脂组成的生物膜结合活性。当加入由酸性或中性磷脂构成的脂质体后,JZTX-I能够分别产生6.4和4.7nm的蓝移以及7.4和8.0nm的红移激发漂移,显示JZTX-I能够插入磷脂膜,同时该分子疏水表面的色氨酸残基处于一个运动受限的界面区域。荧光淬灭实验进一步证实,与脂质体结合能够减少该毒素分子表面色氨酸残基的溶剂暴露。该研究结果为阐明JZTX-I的离子通道门控调节机制提供了新的信息。 相似文献
67.
Kirill Nikitin Helge Müller-Bunz Gérard Jaouen Michael J. McGlinchey 《Journal of organometallic chemistry》2010,695(4):595-608
The McMurry coupling of (tetraphenylcyclobutadiene)cobalt(cyclopentadienyl) ketones, (C4Ph4)Co[C5H4C(O)R], where R = Me, 3a, or Et, 3b, with a range of substituted benzophenones furnished a series of cobaltifens, organometallic analogues of tamoxifen whereby a phenyl ring has been replaced by an organo-cobalt sandwich moiety. These systems of the general formula (η4-C4Ph4)Co[η5-C5H4C(R)C(Ar)Ar′], where R = Me or Et, and Ar = Ar′ = p-C6H4X where X is OH, 2a and 2b, OMe, 2c and 2d, OBn, 2e and 2f, or O(CH2)2NMe2, 12a and 12b, and where Ar = C6H4OH and Ar′ = C6H4O(CH2)2NMe2, 2g and 2h, have been characterised by NMR spectroscopy and/or X-ray crystallography. The effect of 2a and 2b, 2g and 2h, and 12a and 12b on the growth of MCF-7 (hormone-dependent) and MDA-MB-231 (hormone-independent breast cancer cells) was studied. The dihydroxycobaltifens 2a and 2b exhibit a strong estrogenic effect on MCF-7 cells while the aminoalkyl-hydroxycobaltifens, 2g and 2h, were found to be only slightly cytotoxic on MDA-MB-231 cells (IC50 = 27.5 and 17 μM); surprisingly, however, the bis-(dimethylaminoethoxy)cobaltifens, 12a and 12b were shown to be highly cytotoxic towards both cell lines (IC50 = 3.8 and 2.5 μM). 相似文献
68.
V. F. Mironov Yu. I. Sal’nikov G. A. Boos D. A. Tatarinov A. P. Nikitin 《Russian Journal of General Chemistry》2013,83(6):1087-1093
Four new compounds, asymmetrical phosphine oxides containing 2-hydroxyphenylethenyl fragment in cis-orientation with respect to the phosphine oxide: dibutyl-, diphenyl-, dibenzyl-, and dinaphthyl-2-(2-hydroxy-5-chlorophenyl)-2-phenyl-ethenylphospnine oxides, have been studied in aqueous ethanol (80 vol % of EtOH) by means of potentiometry and spectrophotometry at 25±0.1°C, and their acid-base and complexing properties estimated. 相似文献
69.
K. N. Semenov D. G. Letenko N. A. Charykov V. A. Nikitin M. Yu. Matuzenko V. A. Keskinov V. N. Postnov A. A. Kopyrin 《Russian Journal of Applied Chemistry》2011,84(1):44-49
Method of isothermal saturation in ampules was used to study the solubility of fullerenol in distilled water in the temperature range 20–80°C and to determine the composition of its equilibrium crystal hydrates. The pycnometric technique was employed to examine how the density depends of the concentration of fullerenol solutions and the average molar and partial molar volumes of the components in solution at 25°C was calculated. The method of refractometry was used to study the dependence of the refractive index on the concentration of fullerenol solutions and the specific refraction of the solutions was calculated. 相似文献
70.
M. L. Keshtov E. I. Mal’tsev A. M. Lopatin L. N. Nikitin D. V. Marochkin V. P. Perevalov P. V. Petrovskii A. R. Khokhlov 《Polymer Science Series B》2012,54(1-2):106-114
A number of new phenylated polyfluorenes with blue emission are synthesized via the Diels-Alder reaction in chloronaphthalene and supercritical carbon dioxide. It is shown that these polymers are thermally stable. A comparative analysis of their properties shows that a ??green?? solvent is a suitable alternative to organic solvents for obtaining phenyl-substituted polyfluorenes via the Diels-Alder reaction. 相似文献