Selective transport of cesium ion in polymeric CTA membrane containing calixcrown ethers

A series of calixcrown ethers for which the cavity size of the crown ring is varied from crown-6 to crown-7 to crown-8 were examined for the transport abilities toward alkali metal ions. These ligands were incorporated into supported liquid membranes (SLMs) and into polymer inclusion membranes (PIMs) composed of cellulose triacetate (CTA) as a support and 2-nitrophenyl octyl ether (NPOE) and tris(2-butoxyethyl) phosphate (TBEP) as a plasticizer. In both membrane systems, calixcrown-6 showed the best selectivity toward a cesium ion over other alkali metal ions. The polymeric CTA membrane showed more rapid transport rate as well as higher durability than did the SLMs.     

光促进下溴代烃在CH3OH/DMF体系中的羰基化反应

羰基化反应是有机合成中最重要的反应之一,其合成产品分别为醛、酮、酯、羧酸和酰胺等一系列化合物,可用作溶剂、增塑剂、润滑剂以及天然产物的替代品。卤代烷烃种类繁多,价格低廉,以其为底物进行羰基化反应,可以得到多种多样的羰基化合物。但常规羰基化反应往往需要高温(150-2     

Ar原子电离能谱和Ar3p电子动量谱研究

电子动量谱学（ElectronMomentumSPectroscoP则是近．二十年来发展起来的一种新兴的探测原子、分子和固体结构的手段，它不仅能够获得轨道结合能的信息，而且能够能壳分辨地得到轨道电子的动量分布（即动量表象中的波函数模方）；同时它还是研究电子关联的最有效的实验手段．其     

生物质裂解产物的制备及HPLC检测其成分的虚拟仿真实验开发

In order to improve university laboratory teaching and practical education under the background of information technology, as well as overcome the difficulty for practical training, develop a virtual simulation experiment platform for rapid pyrolysis of natal materials and high-performance liquid chromatographic (HPLC) detection of its components. The experiment integrates the actual operation process of the plant to produce cleaved products by rapid pyrolysis of biomass with HPLC detection. The virtual experiment is divided into biomass sample pretreatment, rapid biomass pyrolysis, bio-oil extraction, and HPLC determination of complex components, making the biomass cleavage workshop "real" through simulation. This virtual simulation experiment fully integrates the utilization of biomass resources and basic chemistry courses (such as organic chemistry, instrumental analysis, chemical engineering principles, etc.), which are widely involved in agricultural and forestry majors with advantageous characteristics value.     

离子交换树脂纯化酪蛋白磷酸肽研究

通过单因素实验和正交试验确定了使用D-201型大孔强碱性阴离子交换树脂纯化酪蛋白磷酸肽(CPPs)的操作条件为：洗脱温度40℃、洗脱酸(HCI)浓度0．2mol／L、洗脱速度2．3ml／min、进样浓度2％(w／v)，进一步应用HPSEC技术分析考察了离子交换树脂纯化后含磷洗脱峰分子量分布情况，并计算了产品氮磷比与纯化收率．     

顺丁烯二酸二异辛酯的合成

以顺丁烯二酸酐和异辛酯为原料，用对甲苯磺酸作催化剂合成顺丁烯二酸二异辛酯。用正交试验确定了酯化反应的优化条件，酯化率达97．96％．     

高分子玻璃化转变过程的分子动力学模拟本科教学实验

玻璃化转变是高分子专业教学中的重要内容,转变过程中自由体积的变化和分子链段的运动是理解玻璃化转变的难点。在计算机上使用分子模拟的方法得到三维的可视化图形,可以更直观地观察到自由体积和分子链的变化。提炼近年分子模拟技术在玻璃化转变研究中的最新科研成果,得到既有理论基础又适合本科教学的课程素材。分子模拟可以实现了仪器测试无法达到的超快速升降温,并与仪器测试得到的实验结果相对照,验证了普通实验很难验证的理论观点,从而拓展了本科实验的范围,达到了很好的教学效果。     

To what extent can an uncertainty calculation be general?

 It is argued that results of uncertainty calculations in chemical analysis should be taken into consideration with some caution owing to their limited generality. The issue of the uncertainty in uncertainty estimation is discussed in two aspects. The first is due to the differences between procedure-oriented and result-oriented uncertainty assessments, and the second is due to the differences between the theoretical calculation of uncertainty and its quantication using the validation (experimental) data. It is shown that the uncertainty calculation for instrumental analytical methods using a regression calibration curve is result-oriented and meaningful only until the next calibration. A scheme for evaluation of the uncertainty in uncertainty calculation by statistical analysis of experimental data is given and illustrated with examples from the author's practice. Some recommendations for the design of corresponding experiments are formulated.     

PVC DISULFIDE AS CATHODE MATERIALS FOR SECONDARY LITHIUM BATTERIES

PVC disulfide (2SPVC) was synthesized by solution crosslink and its molecular structure was confirmed by infrared spectrum. 2SPVC's specific area is 36.1 m2·g-1 tested by stand BET method, and granularity experiment gives out the particle size of d0.5= 11.3μm. With SEM (Scanning Electron Microscope) experiment the surface morphology and particle shape of 2SPVC were observed. Cyclic voltammetry (scan rate: 0.5 mV·s-1) shows that 2SPVC experience an obvious S-S redox reaction in charge-discharge process. When 2SPVC was used as cathode material for secondary lithium battery in a 1 mol·L-1 solution of lithium bis(trifluoromethylsulfonyl) imide (Li(CF3SO2)2N) in a 5:45:50 volume ratio mixture of o-xylene (oxy), diglyme (DG) and dimethoxymethane (DME) at 30℃, the first discharge capacity of 2SPVC is about 400.3 mAh·g-1 which is very close to its theoretical value (410.5 mAh·g-1) at a constant discharge current of 15 mA·g-1. It can retain at about 346.1 mAh·g-1 of discharge capacity after 30 charge-discharge cycles. So 2SPVC is a very promising cathode candidate for rechargeable lithium batteries.     

热敏电阻温度计的设计与制作

本文介绍了设计性实验“热敏电阻的设计与制作”的实施情况。说明了只要选题合适、要求恰当,设计性实验不仅可行,而且对物理实验训练的总结提高十分有效。