Synthesis,Crystal Structure and Characterization of a New Zinc Citrate Complex

A new Zn-citrate coordination complex {K[Zn(C6H5O7)(H2O)]}n(1) was synthesized via hydrothermal reaction. In the crystal structure of complex 1, each citrate serves as the quadricdentate ligand coordinating to three Zn(II) ions, forming a zigzag chain, and such chains are further connected into a 3D network by the K+ linkers. Crystal data for complex 1: triclinic, space group P1, a = 7.3487(9), b = 7.5397(6), c = 9.6772(8) ?, α = 76.894(8), β = 68.260(10), γ = 65.155(10)°, V = 450.34(7) ?3 and Z = 2. Other characterizations by elemental analysis, IR, TG and fluorescence were also described.     

聚(N-异丙基丙烯酰胺)/聚丙烯酰胺无机/有机互穿网络水凝胶的制备及表征

通过紫外引发聚合方法制备了无机交联的聚(N-异丙基丙烯酰胺)(PNIPAAm)/有机交联的聚丙烯酰胺(PAAm)互穿网络(IPN)水凝胶.利用FTIR和SEM分别表征了凝胶的化学结构和内部形态;测定了凝胶在高温(50℃)时的退溶胀性能;利用DMA和DSC分别研究了凝胶的储能模量随温度的变化及热相转变行为.研究表明,该IPN凝胶具有温度敏感性;与未互穿的无机交联PNIPAAm凝胶相比,IPN凝胶具有多孔的网络结构和超快的响应速率,如10min内失去90%的水;其储能模量增加了3～4倍,相转变行为变弱,而最低临界溶解温度(LCST)提高了1.4℃.     

新试剂用径向基函数网络光度法同时测定微量的镉镍

合成一种新的显色剂(4,4'-二偶氮苯基-2-羧基-重氮氨基偶氮苯,BBDDAB),对镉、镍有灵敏的显色反应,最大摩尔吸光系数分别达到1.90×10～5L·mol-1·cm-1和1.56×10～5 L·mo-1·cm-1.镉镍在最大吸收波长在524和540 nm处线性范围分别为0～0.40μg/mL.和0～0.32μg/mL.尽管两种络合物光谱重叠较严重,但采用分光光度法结合化学计量学中的人工神经网络方法(RBFANN)可实现镉镍的同时测定.     

Synthesis and Characterization of Self-oscillating P（AA-co-AM）/PEG SemiIPN Hydrogels Based on a p H Oscillator in Closed System

Various semi-interpenetrating polymer network（semi-IPN） hydrogels composed of pore-forming agent polyethylene glycol（PEG）, acrylic acid（AA） and acrylamide（AM） were prepared by using free radical polymerization with a two-step method. The chemical structures of the synthesized hydrogels were characterized by FTIR spectroscopy and the morphologies were studied by scanning electron microscopy（SEM） method. The swelling properties, such as the p Hresponsive behavior, salt sensitivity, oscillatory swelling/de-swelling behaviors in different solutions with various p H values and self-oscillating behaviors in bath p H oscillator were investigated in detail. The results revealed that the prepared hydrogels exhibited high p H sensitivity and excellent salt sensitivity when the p H values of the medium changes from 3.0 and 7.0 and well reversible properties by undergoing a number of swelling/de-swelling recycles. In particular, the hydrogels exhibited self-oscillation behavior in a closed system containing Br O3？-SO32？-Fe（CN）64？-H＋. This study may create a new possibility as biomaterial for new self-walking actuators and other devices.     

Two new oplopane sesquiterpenes from Artemisia gmelinii Web. ex Stechm.

Two new oplopane sesquiterpenes, gmelinin A（1） and gmelinin B（2）, were isolated from Artemisia gmelinii Web. ex Stechm. Their structures were established by spectroscopic techniques（mainly 1D and2 D NMR） and application of the modified Mosher method.     

《中国稀土学报》中、英文版有关版权转让声明

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小波包压缩-RBF网络同时测定润滑油中铁、铜、锌

将小波包压缩-RBF网络方法用于润滑油中铁铜锌三组分分光光度同时测定该方法采用小波包函数对光谱数据进行压缩处理,用较大的小波色系数构成新的校正集和预测集代替原始的校正集和预测集,然后用RBF网络进行数据解析。研究表明,用bior2．4小波包处理原始测定数据,最佳小波基用logenerge熵标准,选择适当阈值将变量数由46个压缩成25个（压缩比为0．54）,整体预测效果最好。将此方法用于合成样预测．预测结果与实际浓度的相对误差绝对值在2．50％～9．40％之间;用于实际润滑油样品中铁、铜和锌的同时测定,解析值与原子吸收法（AAS）的测定值的相对误差绝对值作3．55％～7．86％之间。应用结果令人满意。     

单体结构对聚合物稳定胆甾相液晶形貌及光电性能的影响

采用紫外光聚合诱导相分离法制备聚合物稳定胆甾相液晶(PSCT),研究了单体4,4′-二[6-(丙烯酰氧基)己氧基]联苯(BAB6)、2-甲基-1,4-二[4-(3-丙烯酰氧基已氧基)苯甲酸基]对苯二酚(HCM-009)、2-甲基-1,4-二[4-(3-丙烯酰氧基丙氧基)苯甲酸基]对苯二酚(LCM)对常黑和常白模式PSCT光电性能的影响。结果表明:BAB6不具备液晶性,与液晶的相容性差,形成的聚合物网络疏松,网孔较大;HCM-009和LCM均具有液晶性,能很好地溶于液晶中。BAB6、HCM-009、LCM 3种单体形成的聚合物网络对液晶分子的锚定作用依次增强,常黑模式PSCT的闲值(饱和)电压减小,下降时间变长,迟滞宽度变大;而常白模式PSCT的驱动电压增大,响应速率变快。     

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