一维链状镉配合物的合成及结构表征

在甲醇体系中合成了镉配合物[Cd(L)₂(H₂O)₂](ClO₄)₂·MeOH (1)[L=1,3,5-三(3-吡啶基甲氧基)苯]。通过元素分析及X-射线单晶衍射对其进行了表征。结构分析结果表明该化合物属于三斜晶系,P1空间群,晶胞参数为a=1.057 1(5) nm,b=1.059 0(5) nm,c=1.270 8(7) nm,α=87.460(16)°,β=81.895(17)°,γ=62.326(14)°,晶胞体积V=1.247 0(11) nm³,Z=1,D_calc=1.569 g·cm^-3,F(000)=604,μ=6.26 cm^-1,R=0.035 2,wR=0.066 4。在化合物1中,每个Cd(II)的配位环境为变形八面体,而每个配体L通过其两个吡啶基团连接2个Cd(II)形成一维链状结构,并进一步通过O-H…N,O-H…O和C-H…O氢键作用形成了一个具有三维结构的超分子化合物。     

用光谱法研究奥硝唑与人血清白蛋白的相互作用

采用荧光光谱法和紫外可见吸收光谱法研究了奥硝唑与人血清白蛋白之间的相互作用;求得了二者在不同温度下的结合常数KA和结合位点数n,以及对应温度下结合反应的热力学参数,同时采用同步荧光分析技术探讨了蛋白质与药物结合时构象的变化.结果表明,在生理条件下奥硝唑对人血清白蛋白的荧光猝灭主要为静态猝灭;奥硝唑与人血清白蛋白主要靠静电作用力结合.     

Dependence of Structure and Haemocompatibility of Amorphous Carbon Films on Substrate Bias Voltage

Tetrahedral amorphous hydrogenated carbon (ta-C:H) films on Si(lO0) substrates were prepared by using a magnetic-field-filter plasma stream deposition system. Samples with different ratios of sp^3-bond to sp^2-bond were obtained by changing the bias voltage applied to the substrates. The ellipsometric spectra of various carbon films in the photon energy range of 1.9-5.4eV were measured. The refractive index n and the relative sp^3 C ratio of these films were obtained by simulating their ellipsometric spectra using the Forouhi-Bloomer model and by using the Bruggeman effective medium approximation, respectively. The haemocompatibility of these ta-C:H films was analysed by observation of platelet adhesion and measurement of kinetic clotting time. The results show that the sp^3 C fraction is dependent on the substrate bias voltage, and the haemocompatibility is dependent on the ratio of sp^3-bond to sp^2-bond. A good haemocompatibility material of ta-C:H films with a suitable sp^3 C fraction can be prepared by changing the substrate bias voltage.     

眼球玻璃体液流变性初探

本文测量承不同切变率下的玻璃体流表观粘度，发现玻璃体液为非牛顿流体，表现出剪切稀化特性，观测到下班 液具有法向应力，表现出弹性液体的特性。     

一款小巧时尚的DLP投影机:瑞诚D2000

最近,朋友邀请共赏一款新购的DLP投影机,这款投影机很小巧,只有一本杂志大小(28cm×20cm×9cm),重量仅2Kg,仔细端详一番,原来是国内企业瑞诚科技出品的D2000投影机。这款投影机的外观设计不错(图1),银色机身散发着灵巧时尚的气息。前面是镜头和出风口,顶部凹槽中有变焦调整钮,底部是三脚支撑,前脚可以伸缩,以调整投影仰角,为了保证机身平整,后部一只脚为可旋式,以便调整高度。由于体积小,侧面几乎都是进风口,但是没有发现可抽出的滤尘网,可能是DLP投影机与液晶投影机的差别吧,因为DLP器件的面积很小,仅仅只有0.55英寸,不像液晶机容易沾…     

教你选购数码摄像机

每当旅游归来取回洗印的照片观看时,是大家最欢乐的时刻,那些凝固了的美好瞬间又将我们带回畅游的乐境之中。但是翻看照片之余总会使人觉得还有很多亲历的美境没有拍下,想再返回去一般是不可能的了,特别是去国外。这时就很羡慕那些有摄像机的人,不仅能拍下更多的内容,还能留下动态的情景,甚至那当时的环境     

Identification of Newβ-Delayed γ Rays and a Low-Spin Isomer in^176Ir

The β＋/EC decay of doubly odd nucleus ^176Ir has been studied via the ^146Nd（^35Cl, 5n7） heavy ion fusion evaporation reaction at 210MeV bombarding energy. With the aid of a helium-jet recoil fast tape transport system, the reaction products were transported to a low-background location for measurement. Based on the data analysis, the previously known γ rays from the decay of ^176Ir are proven. Moreover, three new excited levels and ten new γ rays are assigned to ^176Os. The time spectra of typical γ rays clearly indicate a long-lived low-spin isomer in ^176Ir.     

基于吡啶-4-甲酸构筑的二维Cu(Ⅱ)配位聚合物及其密度泛函研究

采用上下层扩散法合成了一种新型配合物[Cu(IN)2(CH3OH)2](1)(HIN=吡啶-4-甲酸),通过X射线单晶衍射测定了晶体结构,并用元素分析、红外光谱、热分析、磁学性质等技术对其进行了表征.配合物1属单斜晶系,空间群C2;晶胞参数为:a=0.947(3)nm,b=1.333(3)nm,c=0.746(18)nm,β=128.25(5)°,Z=2,V=0.740(3)nm3,Mr=371.83,Dc=1.669Mg?m-3,μ=1.510mm-1,F(000)=382,最终偏离因子R1=0.0751,wR2=0.1468.配合物1的中心原子Cu(II)与4个吡啶-4-甲酸根及2个甲醇分子配位,形成具有畸变八面体的几何构型;吡啶-4-甲酸配体采用桥联模式连接Cu(II)原子形成二维(4,4)层状结构;进而籍层间C—H…O氢键作用拓展为具有二重穿插的α-Po拓扑网络的三维超分子结构.此外,利用B3LYP方法,在6-31G(d)基组水平上对化合物1进行几何构型优化,在此基础上,采用对称性破损(BS)方法研究了配合物的磁性,计算结果表明配合物1具有弱的反铁磁相互作用.