微机控制动态配气装置的研究

按照ISO6145标准，设计，研制了微机控制动态配气装置，实现了微机对动态配气装置主要动态参数的实时监控，存储和结果处理，将该动态配气装置与静态容量法配气装置进行了比较，两种方法配制的标准气体的量值一致，对动态法配气的量值不确定度进行了评定。     

苯系物扩散管气体标准物质的研制

按照ISO 6145—2003、ISO 6144—1998标准,研制了新型气体标准物质动态配气装置,实现了微机对动态配气装置主要参数数据的实时监控。用该装置研制了氮中微量苯系物扩散管气体标准物质,量值的相对扩展不确定度为2％-3％,并与静态容量法配气进行了比较。     

丙硫醚动态配气装置的研制

为实现糜烂性毒剂化学报警器的现场校准，解决评价防护材料对丙硫醚“气-气”防毒时间时丙硫醚浓度波动大的问题，研制了丙硫醚动态配气装置。考察了称量瓶、密封垫片等材料对丙硫醚的吸附及渗透性，选择聚四氟乙烯材质的称量瓶、渗透膜及氯化丁基胶材料的密封垫片。丙硫醚动态配气装置由发生系统、空气净化清洗单元、流量控制系统、抽气泵、电源控制系统等部件组成，该装置能实现一次制备1 mg/m³丙硫醚标准气体，且配气稳定性符合JJF 1343—2022规范的考核要求。     

动态配气法制备氮气中乙醇扩散管气体标准物质

用动态配气装置配制体积分数为10^-6的氮气中乙醇扩散管气体标准物质，其量值不确定度为2%-3%。与静态容量法配制的乙醇气体标准物质进行比对，结果的相对误差为3.5%-4.0%。     

气体传感器气敏性能测试技术研究进展

对国内文献报道的气体传感器气敏性能测试系统的设计开发情况进行综述。从配气系统、数据处理系统、软件开发三个方面对半导体型气体传感器测试系统的组成进行了概述。配气系统为气敏性能测试提供一定浓度目标气体,分为静态配气法和动态配气法,动态配气法制备出的气体精确度较高,误差较小,可以连续制备气体,是目前主要配气方式。控制器是测试系统的核心部件,负责接收、处理、储存传感器与目标气体反应产生的信号,应用较多的是单片机,其次是ARM微控制器,但都存在内存和存储空间有限的问题。测试软件主要功能是发送指令,实现整个测试系统的有序运行,并实时显示测试结果,目前开发工具种类较多,其中LabVIEW较受青睐。未来气敏测试系统的测试精确度和测试效率还需进一步提高,研究开发功能更加全面的测试系统,来满足其它类型传感器测试需求。     

大气本底温室气体测量标准物质研究进展

综述了温室气体标准物质的制备技术与研究进展。归纳了温室气体标准物质种类和量值不确定度的要求,考察了各种配气技术对温室气体监测需求的适用性。综合讨论了配气技术中的稀释操作、钢瓶处理方式及阀门管线材质对温室气体标准物质量值稳定性的影响,并比较了BIPM和WMO量传体系的差异。     

TiO2超细粉热稳定性的研究

本实验以ＴｉＣｌ４为原料，采用超临界流体干燥法地出ＴｉＯ气凝胶超细粉，在６２３－９２３Ｋ温度范围内考察了其织构和结构的热稳定性。实验发现，随着焙烧温度的提高，样吕的比表面和孔体积减小表面堆积密度增大，同时伴随颗粒烧结长大并连成链状。对ＴｉＯ２气胶超细粉的烧结机理研究表明，其烧结为表面扩散控制过程，烧结活化能为２２２．６ｋＪ／ｍｏｌ。     

指数瓶配气中的几个问题

用指数稀释瓶配制标准气,设备简单、灵活,可一次产生几种组分的一系列浓度标准气。但由于稀释瓶结构设计不够完善,以及操作上的疏忽会给分析带来很大误差。本文介绍自制的稀释瓶以及配气时应注意的一些问题。 (一)稀释瓶的结构:稀释瓶结构是否合理易被人们忽略,如果瓶内存在死空间,气体不能充     

超临界流体干燥过程的分析

以ZrOCl2•8H2O为原料，采用超临界流体干燥（SCFD）法，在短时间内制备出大孔体积高比表面ZrO2气凝胶超细粉．该法具有良好的稳定性和可靠性．建立了醇凝胶中液相含水量的分析方法，为产品质量控制及确认体系是否处于超临界状态提供了依据．对抽提后的溶剂分析表明，SCFD过程是一物理过程．对水的抽提干燥过程亦进行了初步的理论探讨．     

聚吡咯/二氧化锡杂化材料的制备及气敏性研究

化学氧化法制备了聚吡咯(PPy)，并进行了元素分析、TG-DTA分析、FTIR测试。讨论了氧化剂用量对PPy气敏性的影响。用机械共混法制备了含不同聚吡咯的聚吡咯/二氧化锡杂化材料，研究其低温下对有毒气体NH₃、H₂S、NO的敏感性。结果表明，相同条件下聚吡咯/二氧化锡杂化材料的气敏性和稳定性均优于聚吡咯、二氧化锡。60 ℃时，当聚吡咯/二氧化锡杂化材料中聚吡咯的质量分数为5%时，其对体积分数为0.05%的H₂S的灵敏度(V_g/ V_a)达到了104.52，且响应恢复时间短。文章讨论了气体与敏感元件的相互作用机制。这一研究有助于开发低能耗、灵敏度高的气敏元件。     

Determination of petroleum trace impurities in aqueous samples by chromatography in a steam flow

A procedure was developed for the determination of trace petroleum products in water by gas chromatography with steam as the carrier gas. Solid-phase microextraction was used for sample preparation. A method for the stabilization and homogenization of water samples before the analysis and a method for the removal of polar components of the sample were proposed. The precision and accuracy indices of the proposed procedure were estimated for aqueous solutions of a mixture of diesel fuel and oil with a concentration close to the maximum permissible concentration. The relative error in the measurement is no more than ～25% in the concentration range of petroleum products of 0.05–0.5 mg/L.     

氮气中六种氯代烷烃混合标准气体的研制

介绍了氮气中6种氯代烷烃混合标准气体的制备和定值方法。标准气体的组分是二氯甲烷、三氯甲烷、1,1-二氯乙烷、1,2-二氯乙烷、1,1,1-三氯乙烷和1,1,2-三氯乙烷,标准值为5 μmol/mol。考察了标准气体的制备重现性、均匀性和稳定性。结果表明,标准气体在气瓶内均匀性良好,扩展相对不确定度为5%,使用有效期为一年。经与国外的同类标准气体比对,量值有较好的一致性。氮气中6种氯代烷烃混合标准气体的研制为挥发性氯代烷烃的检测提供了计量标准。     

氮中磷化氢气体标准物质的制备

用称量法配制磷化氢气体标准物质,以配制值作为标准值,研制出浓度为10~4 000μmol/mol的氮中磷化氢气体标准物质,其量值相对扩展不确定度U_(rel)=2%(k=2),其均匀性满足FF_α,稳定性满足|b_1|t_(0.95,n-2)·s(b_1)。试验测试和应用结果表明,该标准物质量值准确可靠,均匀性、稳定性和不确定度符合项目任务书的要求,可用于磷化氢气体报警器的检定、校准以及环境监测和化工企业等领域的质量控制、方法确认。     

Development of a new microextraction method based on a dynamic single drop in a narrow-bore tube: application in extraction and preconcentration of some organic pollutants in well water and grape juice samples

A novel sample preparation technique, the microextraction method based on a dynamic single drop in a narrow-bore tube, coupled with gas chromatography-flame ionization detection (GC-FID) is presented in this paper. The most important features of this method are simplicity and high enrichment factors. In this method, a microdrop of an extraction solvent assisted by an air bubble was repeatedly passed through a narrow-bore closed end tube containing aqueous sample. It has been successfully used for the analysis of some pesticides as model analytes in aqueous samples. Parameters affecting the method's performance such as selection of extraction solvent type and volume, number of extractions, volume of aqueous sample (tube length), and salt effect were studied and optimized. Under the optimal conditions, the enrichment factors (EFs) for triazole pesticides were in the range of 141-214 and the limits of detection (LODs) were between 2 and 112 μg L⁻¹. The relative standard deviations (C = 1000 μg L⁻¹, n = 6) were obtained in the range of 2.9-4.5%. The recoveries obtained for the spiked well water and grape juice samples were between 71 and 106%. Low cost, relatively short sample preparation time and less solvent consumption are other advantages of the proposed method.     

Combining membrane extraction with mobile gas chromatography for the field analysis of volatile organic compounds in contaminated waters

A mobile gas chromatographic device (Airmobtx HC 1000 monitor manufactured by Airmotec, Germany), originally designed for the analysis of benzene, toluene, ethylbenzene and xylenes (BTEX) in air, was connected to a flow cell for dynamic membrane extraction. Volatile organic compounds (VOCs) diffuse out of a water stream through a hollow fibre, are enriched onto sorption tubes integrated in the mobile device, and are then thermally desorbed and analysed by gas chromatography-flame ionisation detection. Battery operation of the device enables continuous on-site analysis of VOCs. Influences of the water flow-rate on system response and memory effects were investigated. The linear range of the method depends on the flow-rate of the water sample and did not exceed two orders of magnitude. The detection limits for trichloroethene, chlorobenzene and the BTEX compounds were found to be between 0.1 and 1.0 microg/l using a water flow-rate of 30 ml/min. Dynamic membrane extraction combined with the mobile gas chromatographic device was used for the on-site analysis of contaminated waters in the area of Leipzig.     

钛及钛合金气体标准试样的制备及定值

研究了钛及钛合金的气体标准试样制备工艺和数据处理方案，对标准试样长期考察的结果。证明了它的准确性，稳定性是令人满意的。适用于氢氧分析仪器的校准和分析的验证。     

Uniformly sized molecularly imprinted polymer for (S)-naproxen retention and molecular recognition properties in aqueous mobile phase

A uniformly sized molecularly imprinted polymer (MIP) for (S)-naproxen has been prepared by a multi-step swelling and polymerization method using 4-vinylpyridine (4-VPY) and ethylene glycol dimethacrylate (EDMA) as a functional monomer and cross-linker, respectively. We optimized the preparation method of the MIP by changing the molar amounts of the template molecule and functional monomer. Further, we examined the effects of organic modifier type, column temperature and flow-rate on the retentivity and enantioselectivity for naproxen using a mixture of phosphate buffer and organic modifier (acetonitrile, ethanol and 2-propanol) as an eluent. When the amounts of (S)-naproxen, 4-VPY and EDMA used were 4, 6 and 25 mmol, respectively, the enantioselectivity and resolution for naproxen were good despite the shorter retention. When acetonitrile was used as an organic modifier, the highest column efficiency was obtained for the separation of naproxen enantiomers. With regard to the effects of column temperature and flow-rate, the column performance was improved by elevating a column temperature and decreasing a flow-rate.     

Optimization of a method for the determination of a mustard gas biomarker in human blood plasma by liquid chromatography–high-resolution mass spectrometry

A method for the determination of a mustard gas biomarker (an S-hydroxyethylthioethyl adduct with albumin) in blood plasma was optimized with the use of HPLC with high-resolution tandem mass-spectrometric detection. This method is based on the hydrolysis of this adduct by the proteinase K enzyme with the formation of the following stable tripeptide with cysteine, proline, and phenylalanine: S-[HETE]-Cys- Pro-Phe. The conditions of the sample preparation of human plasma artificially contaminated by mustard gas (the selection of an aliquot portion volume and an enzyme for the hydrolysis), the mass-spectrometric detection (the selection of optimum pairs of ion reactions and high-resolution detection modes), and the gradient elution program in the HPLC separation of an analyzed mixture were optimized. The detection limit of mustard gas in human blood plasma was 1 ng/mL. The approach proposed was tested in the analysis of human blood plasma samples by the standard addition technique and also within the framework of the first official biomedical test carried out by the Organization for the Prohibition of Chemical Weapons (OPCW) in 2016, and it exhibited a good accuracy, reproducibility, and specificity of determination.     

甲苯磺酸异构体的气相色谱分析

为克服在甲苯磺酸异构体定量分析结果中重复性和准确性差的问题，从多种色谱固定液中选出合适固定液，以正十十一烷作为内标物，优化了色谱条件，对气相色谱法研究甲苯磺酸乙酯异构体中的诸多影响因素进行了比较，确定了汽化室温度对于邻、间、对甲苯磺酸乙酯异构体准确测定的影响作用。