海泡石负载Cu催化糠醛气相加氢制糠醇反应

糠醇是一种重要的精细化学品，用于合成耐酸、耐碱和防腐蚀树脂，并用于合成纤维、橡胶、农药等行业，还是呋喃树脂、清漆和颜料的优良溶剂和一种火箭燃料．     

三元配合物[Cu(L-tyr)(TATP)(H_2O)]ClO_4·H_2O的合成、晶体结构及芳环堆积作用

合成了新的三元配合物 [Cu(L tyr) (TATP) (H2 O) ]ClO4 ·H2 O (L tyr=L 酪氨酸 ,TATP =1,4,8,9 四氮三联苯 ) ,并用红外光谱和电子顺磁共振谱进行了表征 .用X射线单晶衍射测定了配合物结构 ,晶体属单斜晶系 ,空间群P2 1,晶胞参数 :a =0 .786 2 (2 )nm ,b=1.0 5 10 (5 )nm ,c=1.476 8(3)nm ,β =97.74(3)° ,Z =2 ,V =1.2 0 92 (5 )nm3 ,R1=0 .0 34 1,wR2 =0 .0 919.中心Cu(Ⅱ )离子具有变形四方锥配位结构 ,与TATP中两个氮原子、L tyr的氨基氮和羧基氧原子及一个水分子配位 .晶体中芳环堆积及氢键作用类似于稳定DNA双螺旋结构的碱基之间的作用 ,具有分子识别的特点 .     

pH位移法评定阻垢剂的阻垢性能

介绍了一种评定阻垢剂性能的新方法，即在某一pH范围内，通过测定加入阻垢剂后Ca(HCO3）2过饱和溶液的起始PH与一定时间后的稳定PH之差，根据差值的变化评定阻垢的阻垢性能，通过与国内普遍采用的评定阻垢剂性能的方法－静态阻垢法和鼓泡法的比较，证明此法简便、快捷，重现性好，可信度高。     

大气降雨俘获空气中短寿命氡子体实验研究

为了研究降雨对空气中短寿命氡子体的清洗机制,设计了分别模拟大气降雨的水汽凝结过程和雨粒下降过程的两个实验装置,并进行了多次实验,实验水样采用低本底 能谱仪进行测量。实验结果表明:凝结水的短寿命放射性计数与本底相近,说明水汽凝结不能俘获短寿命氡子体。某一次自来水冲刷空气后获得了高出本底30.9% 的初始 计数,其半衰期为35.7 min,纯净水冲刷空气后获得了高出本底19.6%的初始计数,这些计数主要是由氡子体214Pb 和214Bi 引起的。可见,无论是自来水还是纯净水,它们冲刷空气后都能俘获短寿命氡子体,且半衰期和放射性核素种类均与雨水相似。这一实验结果充分说明:大气降雨的短寿命放射性不是在水汽凝结阶段而是在降落阶段对空气的冲刷获得的,是在降落过程中俘获了空气中的短寿命氡子体214Pb 和214Bi 而引起的。本次实验结果为降雨对空气中短寿命氡子体的冲刷清洗机制提供了最有力的证据。To investigate the underpinning mechanism of rainfall-scavenging of the atmospheric short-lived radon daughters, two experiments simulating water vapor condensing procedure and raindrop falling procedure were conducted. The radioactivity of the tested water was measured by low-background   γ spectrometry. The obtained results showed that the γ-ray counts of condensed water was on the same level as the background,which proved that water vapor condensation cannot trap short-lived radon daughters. In contrast, the initial γ-ray count of washout water (35.7 min half-life) was increased by 30.9% after washing the atmosphere with tap water. Similarly, the initial  -ray count of washout water was increased by 19.6% after washing the atmosphere with puri ed water. These counts originated mainly from radon daughters 214Pb and 214Bi. Obviously, both tap water and puri ed water can trap short-lived radon daughters when washing the atmosphere. Furthermore, the half-life and the kinds of radioactive nuclides in the washout water are similar to that in the rainfall water.These experimental results are able to ascertain that short-lived radon daughters in precipitation come mainly from scavenging (washout) and not from water vapor condensation within the cloud. It is in the process of falling that raindrops trapped short-lived radon daughters 214Pb and 214Bi. The obtained results as demonstrated here provide a powerful evidence for understanding the washout mechanism of short-lived radon daughters from theatmosphere by rainfall.     

Synthesis,Characterization,and DNA Binding Properties of Dinuclear Copper(Ⅱ)Complex [Cu2(TATP)2(L-Leu)2(CIO4)2]2°2H2O

A dinuclear copper(Ⅱ) complex [Cu2(TATP)2(L-Leu)2(ClO4)2]2.2H2O was synthesized and characterized,where,TATP=1,4,8,9-tetraazatriphenylene,and L-Leu=L-leucinate,The complex was crystallized in the triclinic space group P1,with two independent molecules in a unit cell,Two Cu(Ⅱ) ions in each complex[Cu2(TATP)2(L-Leu)2(ClO4)2]molecule were found to be in different coordination geometries,i.e.,Cu2 or Cu4 of a distorted square-pyramidal geometry coordinated with two nitrogens of TATP,the amino nitrogen and one carboxylate oxygen of L-Leu and one oxygen of perchlorate,and Cul or Cu3 with an octahedral geometry coordinated with the above stated similar coordinated atoms,and another carboxylate oxygen of L-Leu coordinating to Cu2 or Cu4,The complex can interact with CT-DNA by an intercalative mode and cleave pBR322 DNA in the presence of ascorbate.     

pH-Responsive Polycarbonate Copolymer-based Nanoparticles for Targeted Anticancer Drug Delivery

A smart polycarbonate(PCA) copolymer-based nanoparticle(NanoPCA) with pH-responsive, long-term stability, and tumor targeting ability was successfully developed by synthesizing and assembling a series of functional PCA-based copolymers including poly(2-amino-1,3-propanediol carbonate-co-L-lactide)[P(CA-co-LA)], poly(2-amino-1,3-propanediol carbonate-co-L-lactide)-g-methoxy-poly(ethylene glycol)[P(CA-co-LA)-g-MPEG], and poly(2-amino-1,3-propanediol carbonate-co-L-lactide)-g-poly(ethylene glycol)-cyclic(Arg-Gly-Asp-D-Phe-Lys)[P(CA-co-LA)-g-PEG-cRGD] for targeted anticancer drug delivery. pH-Responsive studies demonstrated that the loading doxorubicin(DOX) released faster from NanoPCA at acidic conditions due to protonation effects of P(CA-co-LA) copolymers. Furthermore, the in vitro and in vivo investigations demonstrate that the DOX-loaded NanoPCA exhibited significant tumor targeting ability, outstanding antitumor effect and excellent biological safety in the treatment of oral squamous cell carcinoma(OSCC). Therefore, this work provides a promising drug delivery platform for cancer therapy and other applications.     

间断有限元方法在弹尾超音速喷流计算中的应用

采用间断有限元方法对超音速无粘喷流流动进行数值模拟.将二维双曲守恒方程的间断有限元方法发展到轴对称Euler方程,并就某导弹尾部超音速伴随射流进行数值计算.计算结果与实验照片反映的流动特征吻合较好,与高精度、高分辨率TVD格式的计算结果相比,间断有限元方法的计算结果在轴线反射点附近具有较高的分辨率,表明该方法对激波具有较强的捕捉能力,在激波阵面上不会产生振荡或抹平间断现象.     

德国大学物理实验教学情况介绍

介绍德国大学的学制和物理实验的教学情况,物理实验课很受重视,基础理论结合实际应用的实验设计思想、单个实验丰富的实验内容、编写独特的实验手册、灵活的考核办法和精简的师资安排都颇具参考价值。     

关于Whiteman差集

设p,q是不同的奇素数.本文证明了如果W(p,q)是Whiteman差集,则必有     

温度变化对Eu/TiO2纳米材料的结构和光学性能的影响

研究了温度(包括退火温度,测试温度)变化对Eu3+掺杂TiO2纳米颗粒的结构和光学性能的影响.结果表明:随着退火温度的升高,纳米颗粒的尺寸变大,Eu3+发光增强;而且当退火温度升到973 K时,纳米颗粒的形状由球状变成方形,并开始发生相变;此后Eu3+离子发光峰的强度随着温度升高明显减弱,与此同时生成了一个新的宽荧光峰...