三氟乙氧基磷酸酯的合成与性能研究

为提高锂离子电池安全性，本文制备了锂离子电池阻燃添加剂-三氟乙氧基磷酸酯（TFP）。通过红外（IR）光谱法鉴定了产物结构；讨论了反应时间、反应物浓度比与产率的关系；以及TFP的加入对1mol／L LiPFoEC／EMC／DMC（1：1：1Vol．）电解液的可燃性、分解电压和离子电导率的影响。结果表明：反应时间、反应物浓度比对TFP产率影响较为明显，当催化剂为15mol．％（相对于三氯氧磷），反应时间6h，三氟乙醇与三氯氧磷摩尔比为6：1时，TFP的产率可以达到94．00％；添加TFP对电解液阻燃效果显著，对电解液的分解电压无不利影响，电解液电导率会有所下降，对Li／LiCoO2电池的比容量影响不大。     

PbMoO4晶体生长基元和生长习性的高温拉曼光谱研究

应用高温拉曼光谱研究了PbMoO4熔体中的生长基元.通过对不同温度下PbMoO4晶体拉曼光谱和熔点温度附近熔体高温拉曼光谱的研究,发现PbMoO4熔体中存在Pb2 阳离子和[MoO4]2-阴离子生长基元.进一步讨论了PbMoO4晶体生长基元和各个低指数晶面间的相互作用,解释了晶体的生长习性和枝晶生长的原因,并指出:PbMoO4晶体生长的最佳籽晶取向是平行于其{101}面所围成的棱锥表面的方向.     

单核铜配合物Cu(C_(16)H_(13)N_2OS_2)_2的合成、晶体结构和生物活性(英文)

A planar copper complex Cu(L)2,HL=(E)-benzyl-2-(4-formylbenzylidene)-Hydrazinecarbodithioate,has been prepared via the template effect of copper ion. Crystal structure of the complex was determined by X-ray singlecrystal diffraction analysis. The crystal data for this complex:Orthorhombic,space group Pbcn,a=2.250 0(14) nm,b=1.660 0(11) nm,c=0.830 4(5) nm,V=3.102(3) nm3,Z=4,μ=1.011 mm-1,Dc=1.478 g·cm-3,F(000)=1 420,R1= 0.050 1,wR2=0.087 2 (observed reflections with I2σ(I)) and R1=0.129 1,wR2=0.100 9 (all reflections) GOF= 1.011. In the compound,Cu(Ⅱ) atom is four-coordinated with two N atoms and two S atoms from two bidentate ligands and located in the inversion center. The preliminary bioassay indicates that the complex exhibits distinct antitumor activity.     

固相萃取-高效液相色谱法测定浓缩苹果汁中的多菌灵残留量

报道了固相萃取-高效液相色谱法测定浓缩苹果汁中多菌灵残留量的方法.样品经适量水稀释后,C18固相萃取柱提取净化,用V(甲醇)∶V(二氯甲烷)=1∶1淋洗,HPLC法测定.在添加水平为0.10,0.50,2.0 mg/kg时,多菌灵的回收率在92.6%～108.3%之间;RSD＜3% (n=6),检出限为0.02 mg/kg,该方法的测定结果满足农药残留量的检测要求.     

Dynamic properties of epidemic spreading on finite size complex networks

The Internet presents a complex topological structure, on which computer viruses can easily spread. By using theoretical analysis and computer simulation methods, the dynamic process of disease spreading on finite size networks with complex topological structure is investigated. On the finite size networks, the spreading process of SIS （susceptibleinfected-susceptible） model is a finite Markov chain with an absorbing state. Two parameters, the survival probability and the conditional infecting probability, are introduced to describe the dynamic properties of disease spreading on finite size networks. Our results can help understanding computer virus epidemics and other spreading phenomena on communication and social networks. Also, knowledge about the dynamic character of virus spreading is helpful for adopting immunity policy.     

化学计量比LiNbO3晶体的激光显微拉曼光谱研究

对用助熔剂提拉法生长的近化学计量比LiNbO3晶体进行了激光显微拉曼光谱测试分析,与同成分LiNbO3晶体相比较,A1(TO)与E(TO)模的谱线数目、频率基本不变,验证了LiNbO3晶体属置换式固溶体的结论.738cm-1处拉曼振动峰（A1(LO)模）的相对强度随晶体中Li2O含量的增加发生了明显的变化,在两种掺杂晶体中,此振动峰已经消失.根据Li空位模型,从占位和结构上进行了分析讨论.在152和872cm-1处拉曼振动峰半高宽随晶体中Li/Nb的增大而变窄,对二者关系进行了线性拟合,利用拟合公式可根据拉曼振动峰半高宽计算晶体中的Li/Nb值. 关键词： 化学计量比 拉曼光谱 线性拟合 半高宽     

窄禁带稀磁半导体二维电子气的拍频振荡

通过对调制掺杂的n型Hg_0.82Cd_0.16Mn_0.02Te/Hg_0.3Cd_0.7Te第一类量子阱中磁性二维电子气磁阻拍频振荡的研究，发现温度、栅压的变化都会引起磁阻拍频节点位置的变化.从对拍频的分析中，可以将依赖于栅压的Rashba自旋-轨道分裂和依赖于温度的巨大塞曼分裂区分开来. 关键词： 磁性二维电子气 自旋分裂 sp-d交换相互作用 拍频     

流体/准饱和多孔介质中伪Scholte波的传播特性

研究流体/多孔介质界面Scholte波的传播特性对于水下勘探、地震工程等领域具有重要意义.本文基于Biot理论和等效流体模型,采用势函数方法,推导了描述有限厚度流体/准饱和多孔半空间远场界面波的特征方程和位移、孔压计算公式.在此基础上,分别以砂岩和松散沉积土为例,研究了流体/硬多孔介质和流体/软多孔介质两种情况下,可压缩流体层厚度和多孔介质饱和度对伪Scholte波传播特性的影响.结果表明：多孔介质软硬程度显著影响界面波的种类、相速度、位移和水压力分布;有限厚度流体/饱和多孔半空间界面处伪Scholte波相速度与界面波波长和流体厚度的比值有关;孔隙水中溶解的少量气体对剪切波的相速度的影响不大,对压缩波相速度、伪Scholte波相速度和孔隙水压力分布影响显著.     

Grain size and its distribution in NiTi thin films sputter-deposited on heated substrates

Grain size and its distribution in NiTi thin films sputter-deposited on a heated substrate have been investigated using the small angle x-ray scattering technique. The crystalline particles have a small size and are distributed over a small range of sizes for the films grown at substrate temperatures 370 and 420℃. The results show that the sizes of crystalline particles are about the same. From the x-ray diffraction profiles, the sizes of crystalline particles obtained were 2.40nm and 2.81nm at substrate temperatures of 350 and 420℃, respectively. The morphology of NiTi thin films deposited at different substrate temperatures has been studied by atomic force microscopy. The root mean square roughness calculated for the film deposited at ambient temperature and 420℃ are 1.42 and 2.75nm, respectively.     

激光与近视眼治疗

 近视眼给亿万患者带来了极大的痛苦.配戴眼镜不仅不能从根本上治疗近视,而且还会给患者的生活带来许多不便.因此,寻找更好、更有效的治疗方法是眼科医生和科学家们的共同心愿.