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THE BUOYANT TWO-DIMENSIONAL LAMINAR VERTICAL JET 总被引:2,自引:0,他引:2
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ZHANG Yu-Hua YUAN Jian-Chao ZHANG Wei-Qiang YIN Yuan-Qi ZHOU Zhong-yuan Albert S.C.CHAN 《结构化学》2001,20(5)
The hetero-metal clusters [h5-C5H4C(O)CH2CH2C(O)OCH3]FeCoM(m3-S)(CO)8 (M = Mo 1, M = W 2) were prepared by thermal reactions of FeCo2(CO)9(m3-S) with metal exchange reagent [h5-C5H4C(O)CH2CH2C(O)OCH3]M(CO)3Na (M = Mo or W) in THF. Cluster 1 reacted with 2,4-dinitrophenylhydrazine at room temperature to yield the cluster hydrazone derivative (m3-S)CoFeMo(CO)8[h5-C5H4C(NR)Me] [R = NHC6H3-2,4-(NO2)2] 3. All the compounds were characterized by elemental analyses, IR and NMR spectra. Cluster 1 was determined by single crystal X-ray diffraction. Crystal data: C18H11O11SCoFeMo, Mr = 646.05, triclinic, space group P_1, a = 8.148(2), b = 10.685(3), c = 13.410(4) ?, a = 100.077(5), b = 102.452(5), g = 91.108(6)°, V = 1120.4(5) ?3, Z = 2, Dc = 1.915 g/cm3, F(000) = 636, m = 2.071 mm-1, the final R = 0.0378 and wR = 0.0968 for 5074 observations with (I > 2s(I)). 相似文献
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IntroductionMagnetic microspheres have been widely usedin many fields,such as targetdrug,cell separationand enzyme immunoassay,since the past twentyyears because of their relatively rapid and easymagnetic separation[1] .Although a poly(ethyleneoxide) supported- catalyst system with a solublepolymer as the carrier can easily keep the activityand the selectivity of the catalyst,its recovery hasto be performed by filtration or precipitation fromthe reaction medium,which is time- consuming andener… 相似文献
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Through three stories about nitrates, a storytelling technique is used to describe the main uses of nitrates today, including agricultural fertilizers, industrial explosives, and food preservatives. Nowadays, nitrate is suspected to be the main cause of carcinogenesis, but one coin has two sides; in fact, nitrates play an important role both in the ecological environment and in the human body. Therefore, the public can understand more about the applications of nitrates from this article. Through the accidental discovery of a rural couple in a wartime setting, this article describes the uses of nitrate in agriculture, antiseptic, immune systems and blood circulation system. 相似文献
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A unified approach to the variational dualities in the stateregulator of control theory and linear estimation with and withouttime delay is developed by the complementary variational technique.New variational duals for the state regulator with time-delayand estimation problems with and without time delay are presented. 相似文献
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甘蓝型油菜抗(耐)菌核病近等基因系的创建及抗病性分析 总被引:1,自引:0,他引:1
以抗 (耐 )菌核病显著强于中油 82 1的中R 888、中R 783、宁RS 1作供体亲本 ,中油 82 1作受体亲本和回交亲本创建了甘蓝型油菜抗菌核病的近等基因系 经离体叶片接种菌核病菌抗性鉴定 ,结果表明 3个近等基因系 (NIL)与回交亲本抗菌核病差异极显著 (P <0 .0 1) ,其中以供体亲本中R 888品系抗病性最强 ,NIL的抗病性强弱的排列顺序与抗性亲本的相一致 油菜种子带菌率的测定结果显示 (中油 82 1×中R 888)BC5的带菌率为 0 也与供体亲本的带菌率大小顺序相一致 随机选择的油菜品种 (系 )种子中游离脯氨酸含量分析 ,结果表明 3大类型油菜的脯氨酸含量差异极显著 ,芥菜型油菜 >NIL(甘蓝型油菜 ) >白菜型油菜 >极感病甘蓝型油菜 . 相似文献
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The frequency dependence of electrical conductivity in a 0.1 molar univalent restricted primitive model electrolyte confined in cylindrical pores is studied by non-equilibrium molecular dynamics simulations. At high frequencies, conductivity is independent of pore size and approaches the zero value limit. The phase lag is independent of pore size and approaches the value π/2 at high frequency. At low frequencies, the conductivity is relatively constant and approaches the zero frequency (dc) conductivity value. For pores with radius smaller than 3 times the ion diameter, severe confinement effects lead to different low frequency behaviour. In these very small pores, axial collisions increase at low frequency and lead to much lower conductivity and a negative phase shift. The current response in severely confined electrolytes can be analogous to an LRC circuit with resonance at a characteristic frequency. 相似文献
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