Synthesis,characterization and in vitro cytotoxicity screening of some triarylbismuth(V) di(N‐salicylidene)amino carboxylates and the crystal structure of (2‐HOC6H4CHNCH2CO2)2Bi(C6H5)3

Four novel triarylbismuth(V) di(N‐salicylidene)amino carboxylates were synthesized. Their structures were confirmed by IR, ¹H NMR, ¹³C NMR and elemental analysis. The crystal structure of (2‐HOC₆H₄CH?NCH₂CO₂)₂BiPh₃ was determined by X‐ray diffraction. The in vitro cytotoxicity of all compounds against three human cancer cells (HL‐60, BGC‐823 and MDA‐MB‐435) at 10 µM are reported. Copyright © 2005 John Wiley & Sons, Ltd.     

Regioselective Propargylation of Aldehydes with Propargyl Bromide Mediated by Sn-In in Aqueous Media under Microwave Irradiation

Tin-indium were employed in the propargylations of various aldehydes with propargyl bromide in the presence of SnCl2 and C6H5（CH3）3NBr under microwave irradiation to afford the corresponding homopropargyl alcohols exclusively in high yields. All the reactions were completed smoothly in predominantly aqueous media in 200 seconds only.     

Crystallographic report: A two‐dimensional homochiral coordination polymer: [cadmium(II) bis(S‐(−)‐lactate)]n

In the two‐dimensional (2D) homochiral structure of [cadmium(II) bis(S‐(?)‐lactate)]_n, the lactate ligand adopts a µ₃‐bridging mode to connect two cadmium atoms, leading to the formation of a 2D network. Copyright © 2004 John Wiley & Sons, Ltd.     

Heterogeneous nucleation on the crystallization poly(ethylene terephthalate)

The crystallization behavior of poly(ethylene terephthalate) (PET) with disodium terephthalate (DST) as nucleating agent was investigated. A detailed analysis of the crystallization course from the melt was made with the Avrami expression. The results demonstrated that DST additive can promote the PET crystallization rate in its entire crystallizable temperature range, and the acceleration degree of DST decreases with increasing temperature after a temperature higher than 180 °C. The values of the Avrami exponent indicated that the crystallization mode in Avrami theory is not suitable for the crystallization of these polymers, and the mechanism of the heterogeneous nucleation on PET crystallization is discussed. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2135–2144, 2003     

由对苯二酚合成2,5—二甲氧基对苯二苄氯锍盐

以对苯二酚为基本原料，通过改进的甲氧基化、氯甲基化、锍化３个反应合成，得到（２，５－二甲氧基对苯乙炔）单体双锍盐２，５－二甲氧基对苯二苄氯锍盐，且产率达８４％，并对每步反应的合成条件及原因进行了解释，运用色谱／质谱联用仪和核磁共振仪对每步产物进行了表征     

Formation of optical waveguide in KNSBN crystal by low dose MeV H-ion implantation

The first H-ion implanted Cu-doped (K_0.5Na_0.5)_0.2(Sr_0.75Ba_0.25)_0.9Nb₂O₆ crystal planar waveguide is reported in this paper. Low dose MeV H ion implantation into a crystal of KNSBN has been used to fabricate the waveguide by generating a buried layer of lowered refractive index. Both TE and TM modes are observed. The reconstructed refractive index profiles in the waveguide are obtained using a parametrized index profile reconstruction method. The simulated results of TRIM show that the nuclear collision influences most the ordinary index profile, but in the region of the guide the extraordinary index profile may be related to the electronic energy loss.     

ErdÖs,Jacobson和Lehel的蕴含Pk可图序列猜想

研究经典的Turan极图问题的一种变形.证明了ErdÖs,Jacobson和Lehel关于蕴含P_k可图序列的猜想是正确的.     

纳米复合永磁Pr9Fe74Co12B5Snx(x=0,0.5)的磁化行为与磁黏滞性

用熔体快淬法制备了纳米复合永磁样品Pr9Fe74Co12B5与Pr9Fe74Co12B5Sn0.5,分析了样品的起始磁化、反磁化过程,测得样品的总磁化率、可逆磁化率以及样品的磁黏滞性.结果表明,两样品在室温下均表现为单一硬磁相磁化行为,在低温下表现为双相行为,且由于添加Sn后使晶粒均匀化从而导致样品低温下的双相行为更加明显.添加Sn后引起样品中软磁相含量和软磁相晶粒尺寸的增加,使磁化反转中可逆磁化部分增多,且使反磁化形核场降低.磁黏滞性研究表明,热激活体积与软磁相晶粒的大小有关.     

高吸水树脂凝胶强度的测定

高吸水树脂可用于油田调剖堵水,有机溶剂脱水及农田保水等。高吸水树脂凝胶中的水不易挤出。吸水凝胶的强度的岩芯测定法由于所取岩芯孔洞不均,测定结果重现性差。本文介绍一种测定吸水树脂凝胶抗压强度和抗压能的方法。 将凝胶置于压缩器中,用INSTRON-1121型材料试验机测定极限压强,以抗压强度σ表