测定气体水合物相平衡数据的高压 PVT装置

建立了一套用于研究气体水合物的高压流体PVT（压力－体积－温度）测试系统。分别利用低压和高压传感器在温度268－283．2K时,压力6－40．2kPa和4600－7200kPa范围内采用恒温试压法分别对1,1－dichloro-1-fluoroethane(1,1二氯－1－氟乙烷）和甲烷气体水合物相平衡点进行了测试;并将所得两组数据与文献值相比较。该装置温度、压力范围较宽,可用于气体水合物相平衡实验。     

PVC-PP树脂分离富集/火焰原子吸收光谱法测定海水中痕量铜镍钴

采用自制的聚氯乙烯多乙烯多胺（PVC-PP）树脂,在pH值为5．0的条件下,分离富集海水中的痕量铜、镍、钴,以1．2mol／L盐酸溶液洗脱．火焰原子吸收光潜法测定,富集倍数最大可达100倍（回收率大于90％）。研究了吸附与洗脱的最佳条件,方法检出限分别为铜0．81μg/L、镍0．98μg/L、钴0．57μg/L（富集倍数100,S／N=3）,相对标准偏差小于5％（n=7）,样品加标回收率在90％-105％之间。     

R245fa和其他四种工质在高温热泵中的理论对比

把R245fa和R134a、R11、R1336mzz(Z)和R1233zd(E)四种工质的热物理性质对比,在相同的工况下理论分析了五种工质在中高温热泵中的COP、压缩机排气温度、单位容积制热量、压缩比等性能参数。结果表明,在高温热泵70～100℃的运行区间内,R245fa冷凝压力较低、制热COP高、排气温度相对较低等特性,具有良好的循环性能。R245fa拥有应用于更高冷凝温度工况下的潜质,为今后更为深入的研究提供借鉴。     

方便面中砷元素的形态分析

建立了硝酸提取,高效液相色谱一原子荧光联用技术测定方便面中不同砷形态的分析方法。样品经0．15mol／L盐酸溶液超声提取后离心过滤,上机测试。实验表明：砷的4种形态亚砷酸[As（Ⅲ）]、砷酸[As（V）]、一甲基胂酸（MMA）和二甲基胂酸（DMA）的线性范围为0-50μg／L,相关系数（r）均优于0．9990,检出限在2～8μg／L之间,砷各形态的测量重复性（以RSD表示）均小于5％,样品的加标回收率为78％-118％。同时用原子荧光光度计检测了样品中总砷,并将两种方法测定结果进行了对比,结果符合理论以及文献报道。该方法操作简单快速、结果准确可靠,适用于方便面中砷形态的分析测定。     

用N2O-C2H2原子吸收光谱法测定铜银合金中铁

提出用N2O-C2H2火焰原子吸收光谱法测试镉镍电池材料铜银合金中铁含量．方法具有良好的灵敏度,干扰少,重现性好．铁含量在0．1～30．0mg／L范围内与吸收值呈良好的线性关系．在测试铁含量为6．26mg／L（测定次数n=10）时,其相对标准偏差小于1．0％．标准回收率在97．0%-99．0％（n=6）范围内,适用于镉镍电池材料铜银合金中铁含量的质量控制分析和样品系统分析,结果令人满意．     

C02（CO）8催化苯乙烯氢酯基化制α-苯基丙酸酯研究

以Co2（CO）8为催化剂,对苯乙烯与CO及甲醇氢酯基化反应制α-苯基丙酸甲酯的反应进行了研究,并根据实验结果提出了可能的催化反应机理．考察了催化剂用量、配体、溶剂、CO压力及反应温度等因素对氢酯基化反应的影响．结果表明：以甲苯为溶剂,在n（Co2（CO）8）／n（苯乙烯）=0．06,吡啶为配体且n（吡啶）／n（Co）=2,CO压力6．0MPa、反应温度95℃的较佳条件下反应12h,苯乙烯的转化率接近100％,α-苯基丙酸甲酯的收率达到89．07％,异正比24．35．     

金属钇表面吸附氢同位素的量子力学计算

用量子力学B3P86方法,对H、D、T采用基函数6-311G^**,对Y采用SDD^**,计算了H2、D2、T2及其钇化合物YHn,YDn,YTn(n=1,2,3)的热力学性质,导出H与Y反应的△rHm^θ、△rSm^θ、△rGm^θ和平衡压力与温度的函数关系。文献值La-LaH2的氢化反应热为-209．296kJ／mol,本文计算值Y-YH2在298-700K间为-137．875到-155．477kJ／mol。LaH2．7的分解温度(平衡压力为0．1MPa时的平衡温度)文献值为1124℃,本文计算YH2的分解温度为782．9K。     

ICP-AES法测定钢中的铈

建立了离子体发射光谱仪测定钢中铈元素的方法。为消除共存元素对铈分析游线的光谱干扰,选择Ce413．380nm作为分析线,铈含量在0．005％-0．50％之间工作曲线线性良好。对于含量范围在0．005％-0．10％的铈元素,回收率为85．6％-12．5％,测定结果的相对标准偏差小于9．74％（n=8）;对于含量范围在0．10％-0．50％的铈元素,回收率为99．5％-103．0％,测定结果的相对标准偏差小于3．52％（n=8）。该方法适宜钢中含量范围在O．005％-0．50％的铈元素的测定。     

N,N'-二(2-硫代-5,5-二甲基-1,3,2-二氧磷杂环己基)乙二胺的合成及阻燃性能

以新戊二醇与PSCl3合成2-硫代-2-氯-5,5-二甲基-1,3,2-二氧磷杂环己烷（DDSP）,再与乙二胺反应,合成了-种新型含有磷、氮、硫的阻燃剂：N,N’-二（2-硫代-5,5-二甲基-1,3,2-二氧磷杂环己基）乙二胺（DDPSN）,用元素分析、FTIR、^1HNMR、MS测试技术对其结构进行了表征。采用热重（TG）分析,研究了反应物摩尔比、缚酸剂及催化剂、反应温度对DDPSN产率的影响。结果表明,所合成的标题化合物结构与预期一致．其初始热分解温度大于290℃,在1000℃时仍有24．5％的残炭率。新戊二醇与PSCl3摩尔比为1．75：1时。DDSP产率高达85％,而DDSP与乙二胺摩尔比为1：1．25时,DDPSN产率为89％;采用4-二甲氨基吡啶（DMAP）作为缚酸剂的效果优于吡啶和三乙胺,其加入量为新戊二醇质量分数的1％时．可使DDPSN产率提高到92％,反应温度以0～5℃为宜。其阻燃粘胶膜实验结果表明,DDPSN在粘胶中质量分数为18％时,极限氧指数（LOI）值可达28％．是-种效果很好的阻燃剂。由阻燃粘胶膜燃烧后生成的炭残渣的扫描电子显微镜（SEM）可知,炭残渣表面有很多隆起的泡状物,且试样的断面为蜂窝状结构,表明该阻燃剂为膨胀型阻燃剂。     

反相高效液相色谱法测定人血浆中利培酮及其代谢物的质量浓度

建立了测定人血浆中利培酮及其活性代谢物9-羟利培酮质量浓度的反相高效液相色谱方法。用Zor－baxODSC18色谱柱,以V（甲醇）：V（水）：V（1mol／L醋酸铵）：V（3mol／L氨水）＝300：50：3：1为流动相,检测波长为280nm,流速为0．8mL／min。利培酮的线性范围为2～600μg／L（r＝0．996）,回收率为（98．2±3．5）％,日内与日间的标准偏差分别为4．12％和4．83％;9-羟利培酮的线性范围为2～800μg／L（r＝0．998）,回收率为（97．8±3．8）％,日内与日间的标准偏差分别为4．28％和4．81％。     

Calorimetry under Stress A Preliminary Study in Single Crystalline Cu-Zn-Al Shape Memory Alloys

A non-differential calorimetric analyzer was developed for an INSTRON 1123 machine (a stress-strain-temperature analyzer) with a temperature chamber INSTRON 1110. The study was performed using the Joule effect and pseudoelastic martensitic transformations in single crystals of Cu-Zn-Al alloys. The analysis of the system establishes that: the sensitivity of calorimetric measurements after a filter of two poles and two zeros is 166 mV W^-1 (at 297 K), the noise is near 1.5 μV and the drift is close to 30 μV in 6 h. The reproducibility of the sensitivity working with one sample is better than ±0.3%, and the change to a new sample keeps the value below ±0.5%. The uncertainty in reproducibility in the martensitic transformation (including repositioning) does not overcome ±1.6%. The used calorimetric sensors limit the temperature to 373 K. The furnace control originated fluctuations on the base line (near ±20 μV), which by means of an auxiliary signal processing were reduced to 50% (less than ±10 μV). This revised version was published online in July 2006 with corrections to the Cover Date.     

Kinetics of thermal decomposition of manganese(ii) oxalate

The kinetics of manganese(II) oxalate thermal decomposition in the helium atmosphere was studied on the basis of isothermal measurements in the temperature range from 608 to 623 K. Manganese(II) oxide, MnO, was found to be the final product of reaction. The Avrami-Erofeev kinetic equation was used to describe all the experimental data in the range of decomposition degrees from 0.1 to 0.9. The determined activation energy equals 184.7 kJ mol^-1 with standard deviation ±5.2 kJ mol^-1. The estimated value of parameter n is 1.9 with standard deviation ±0.01 what suggests that the rate limiting step of MnC₂O₄ decomposition is the nucleation of new MnO phase and that the rate of nuclei growth is rising during decomposition. This revised version was published online in July 2006 with corrections to the Cover Date.     

便携式气相色谱仪共用开发平台中多功能一体化控制器模块的研制

基于整体便携式气相色谱仪共用开发平台的设计理念,研制出了多功能一体化控制器模块.模块包括控制器、功率驱动组件和信号采集组件,直接嵌入到便携式气相色谱仪中.经试验考核,色谱柱温度波动不高于±0.1℃,60℃/min速率升温波动的RSD低于0.15%,进样口和检测器温度波动不高于±0.1℃,柱压不高于±0.16 KPa.以浓度为1 mg/m3的苯标准样品连续6次自动抽取1 m L样品进样分析,定性和定量重复性偏差RSD分别为0.1%和4.6%(峰高),温湿度试验为0~40℃和95%,振动试验(无运输包装)位移为25.4 mm、加速度为1.5 g,以频率5~200~5 Hz正弦波振动与XYZ轴向振动,试验结果正常.模块应用到3种新型仪器中效果理想,满足现场及野外应用要求,具有通用、坚固、体积小和功耗低等特点.     

A Simple Equation for Predicting the Volumetric Properties of Mixtures Involving Ionic Liquids

A simple equation has been employed to predict the volumetric properties of binary mixtures involving an ionic liquid. Moreover, we have calculated excess volumetric properties of the studied mixtures using the proposed equation. The outcomes of our computations have been compared with experimental data. The reliability of the proposed model was checked by taking 854 experimental data points over a temperature range from 278 to 358 K; the average absolute deviation of the calculated density and the excess molar volume were found to be 0.50 and 0.80 %, respectively, while the accuracies of our calculations were of the order of ±3 %.     

Comparative studies of oxygenated fuel synthesis with diesel from the measurements of density,speed of sound and refractive index

An experimental investigation on the feasibility and relevance of the tri fuel blends of ethanol and dibutyl ether with diesel was studied to replace pure diesel. The solubility of the ethanol and dibutyl ether with a percentage of 25% and 75% resulted with no phase separation, found miscible and stable with diesel at any percentage. However, the properties such as densities and refractive index experimentally verified for different blend ratios. A density of test samples with various compositions was tested. High precise equipment is engaged to analyze the density, speed of sound, refractive index for various fuel compositions. The temperature ranges between 298 K and 343 K show a greater impact on variation in the fuel properties. Density, speed of sound, refractive indices measured as a function of the temperature with an accuracy of?±?0.001 and?±?0.0001. Further, the validation of experimental method has been tested using Lorentz–Lorenz (L–L) analysis with a deviation of 0.4%. The uncertainty for fluid velocity is?±?0.3 m s^?1, and the experimental estimated excess molar volume uncertainty is 2?×?10^?3 cm³ mol^?1. The substantiation of intermolecular interactions between the liquids is found to be significant in both experimental and prediction analysis of each sample. The exergy destruction specifies with 46% which includes the air flow and chemical heat energy transfer losses.

     

Determination of Organotin Compounds in Wine by Microwave-Assisted Extraction and High Performance Liquid Chromatography–Inductively Coupled Plasma Mass Spectrometry

A new analytical procedure for the determination of five organotin compounds in several matrix wine samples is reported. The organotin compounds were extracted by microwave-assisted extraction with n-hexane. Extraction conditions, such as volume of n-hexane required, extraction temperature, and extraction time, were investigated and optimized by an orthogonal array experimental design. The determination of organotin compounds in the final extracts was carried out by liquid chromatography–inductively coupled plasma mass spectrometry. The procedure showed limits of detection between 0.029–0.049 µg · L^?1. The linearity was in the range of 0.5 to 100 µg · L^?1. The precision expressed as relative standard deviation (RSD) was below 9.43%. The developed method was successfully employed to analyze different matrix wine samples, and some analytes were detected at the level of 0.053 to 1.14 µg · L^?1.     

High‐throughput kinetic analysis of acrylate and thiol‐ene photopolymerization using temperature and exposure time gradients

In this work, a high‐throughput technique for evaluating photopolymers is developed to enable simultaneous measurement of the effects of temperature in combination with exposure time. Temperature and exposure time gradients were produced in orthogonal directions on a single sample, and subsequently sampled using Fourier transform infrared (FTIR) spectroscopy. The technique developed here allows for photopolymerization kinetics to be analyzed rapidly over a large range of industrially relevant temperatures, giving insight into the role temperature and the polymer's glass transition temperature have in dictating the photopolymerization kinetics. In the 70/30 wt % hexyl acrylate and hexanediol diacrylate system, conversion in samples below the glass transition temperature (T_G) was 66 ± 2% after 12 s, significantly lower than the 93 ± 4% conversion at 12 s for samples polymerized at temperatures above the T_G. In addition, a thiol‐ene system was analyzed to study the effect of temperature on the ene homopolymerization in allyl ether monomers, which leads to incomplete thiol conversion in stoichiometrically balanced systems. At a 60% thiol conversion, the allyl ether‐ene conversion at all temperatures is 65 ± 3% irrespective of initial formulation temperature, indicative of the homopolymerization behavior being nearly independent of temperature. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1502–1509, 2008     

Electrolytic conductivity and molar heat capacity of two aqueous solutions of ionic liquids at room-temperature: Measurements and correlations

As part of our systematic study on physicochemical characterization of ionic liquids, in this work, we report new measurements of electrolytic conductivity and molar heat capacity for aqueous solutions of two 1-ethyl-3-methylimidazolium-based ionic liquids, namely: 1-ethyl-3-methylimidazolium dicyanamide and 1-ethyl-3-methylimidazolium 2-(2-methoxyethoxy) ethylsulfate, at normal atmospheric condition and for temperatures up to 353.2 K. The electrolytic conductivity and molar heat capacity were measured by a commercial conductivity meter and a differential scanning calorimeter (DSC), respectively. The estimated experimental uncertainties for the electrolytic conductivity and molar heat capacity measurements were ±1% and ±2%, respectively. The property data are reported as functions of temperature and composition. A modified empirical equation from another researcher [1] was used to correlate the temperature and composition dependence of the our electrolytic conductivity results. An excess molar heat capacity expression derived using a Redlich–Kister type equation was used to represent the temperature and composition dependence of the measured molar heat capacity and calculated excess molar heat capacity of the solvent systems considered. The correlations applied represent the our measurements satisfactorily as shown by an acceptable overall average deviation of 6.4% and 0.1%, respectively, for electrolytic conductivity and molar heat capacity.     

全自动凯氏定氮仪测定干旱区土壤中全氮含量

对采用全自动凯氏定氮仪测定干旱区土壤全氮量的方法以及实验中影响因素进行了研究,对消解时间和硫酸用量进行了选择性实验,结果表明,土壤中有机物在30min时消解完全,硫酸用量在10~15mL时为最佳,干旱区土壤中氮一般含量为(0.260±0.003)%(P=0.95)。方法的相对标准偏差(RSD)≤1%,用来测定硫酸铵标准物质,其检测结果与标准值基本吻合,检测的准确度和精密度都符合国家标准的要求。