一种制备MCM-41/Y分子筛复合材料的新方法

以Y沸石为内核，以异丙醇铝为铝源，正硅酸乙酯为硅源，十六烷基三甲基溴化铵为模板剂，在控制条件下合成了MCM－41／Y分子筛复合材料，用X射线衍射，扫描电镜，低温N2吸附等手段对其物理化学性能进行了表征，用萘的液相叔丁基化反应考察了这种新材料的催化性能，结果表明，这种复合材料与HY相比，对反应的活性虽有所下降，但选择性却大大提高。     

新型亲和吸附剂的研究（I）：吸附剂的制备及其配体固定化

以醋酸乙烯酯为单体，三烯丙基异氰尿酸酯为交联剂制得大孔交联共聚物，以其为载体，氨基酸为配体制得一系列亲和吸附剂，探讨了溶剂用量和性质，反应时间和温度等条件对配体固定化的影响，并确定了最佳制备条件。     

基于二氧化硅纳米颗粒的三重态-三重态湮灭上转换研究

以氟化的四苯基卟啉铂为光敏剂，硅氧烷衍生化的9，10-二苯基蒽为发光体构筑了基于三重态-三重态湮灭机制的上转换体系.采用紫外可见分光光度计和荧光光谱仪研究了其在二氯甲烷溶液中的上转换性能，确定了光敏剂和发光体的最佳比例为1：40.在此比例下，以胶束模板法构筑了尺寸均一，能在水中稳定的上转换二氧化硅纳米颗粒，通过透射电子显微镜（TEM）和动态光散射仪（DLS）表征了其形貌和尺寸（TEM统计平均直径为15.5 nm，平均水合直径为22.5 nm）；当以532 nm的激光作为激发光源时，实现了水中的上转换发射，上转换发光寿命为12 μs，上转换量子效率为0.8%.     

高效毛细管电泳分离/电导检测麻黄碱和伪麻黄碱

采用高效毛细管电泳电导检测法分离麻黄碱和伪麻黄碱，初步探讨了分离机理，建立了检测方法。以柠檬酸－柠檬酸钠为缓冲体系，铜盐为络合剂，在pH值为4．5、电压13.5kV的条件下，盐酸麻黄碱和伪麻黄碱得到了较好的分离，加入适量乙醇可改善峰形和分离效果。用该法以水杨酰胺为内标，对含盐酸麻黄碱和伪麻黄碱的实际样品进行检测，回收率为97.3%-101.1%，结果令人满意。     

无溶剂体系酪氨酸酶催化对位苯酚类化合物与芳香胺的反应研究

以对苄氧基苯酚，对苄基苯酚和对苯氧基苯酚作为底物，研究在无溶剂体系下，酪氨酸酶分别催化它们与邻氨基苯甲醚的反应。考察了在无溶剂体系下，以底物200μmol为当量，酶催化该类反应的最适水含量为30～35μL，加酶量为35～40mg，反应时间为24h，以此为反应条件酶促催化合成了2和3b，3a，产率30～50％，并讨论了反应机制。     

纳米TiO2光催化降解CH3OH、HCHO及HCOOH反应的研究

以纳米TiO2为催化剂，采用主波长为364nm的汞灯为光源，分别研究了浓度为0.1mol/L的甲醇、甲醛和甲酸水溶液的光催化氧化反应速率，用TEM、XRD、SSA和FT-IR对催化剂进行了表征，通过气相色谱测定反应物和生成物的浓度变化。并用Langmuir-Hinshelwood方程进行计算，证明该组反应均为零级反应，根据红外光谱的检测结果，提出了甲醇光催化的反应机理。     

壳聚糖固定化胰蛋白酶的研究

以壳聚糖为载体，戊二醛为交联剂，采用两种方法制备了固定化胰蛋白酶。考察了固定化反应中pH值，戊二醛的浓度，以及给酶量对固定化胰蛋白酶活力的影响，并研究了这两种固定化胰蛋白酶的性质。实验结果表明，以戊二醛预交联的网状壳聚糖为载体制备的固定化胰蛋白酶具有更加优良的性能，在最佳固定化反应条件下，酶的活性加收率可达56％。此固定化胰蛋白酶的最适pH为7．0－8．5，最适温度为60℃，Km值为2．52mol/L，固定化胰蛋白酶表现出较好的热稳定性，pH贮存稳定性，以及在乙醇水溶液中的稳定性。     

尿酸-铁氰化钾-鲁米诺化学发光测定亚硝酸盐

在酸性介质中，亚硝酸盐氧化亚铁氰化钾为铁氰化钾，利用尿酸-铁氰化钾-鲁米诺化学发光体系，建立了一种间接测定亚硝酸盐的新方法。讨论了酸度、反应物浓度、干扰离子等因素的影响。方法的检出限为0.05μg/L，对样品进行了平行测定（n=11），其相对标准偏差为1.8%-3.2%，线性范围为0.001-10ng/L。方法简便，易于操作，并具有较高的灵敏度和选择性。用于环境水样及食品中亚硝酸盐的测定，回收率为95.7%-105.8%，结果令人满意。     

电位滴定法测定石膏中三氧化硫的方法研究

研究了ＥＤＴＡ滴定Ｐｂ＾２＋过程中溶液的电位变化，建立了以双液接饱和甘汞电极为参比电极，铅电极为指示电极，ＥＤＴＡ为滴定剂电位滴定法测定石膏，水泥中三氧化硫，方法准确度高，结果稳定，操作简便。     

高分子结晶的新进展、新模型

回顾了高分子结晶经典模型－成核与生长模型，讨论了近年来高分子结晶研究的新结果，新进展，特别介绍了德国著名高分子物理学家Strobl提出的高分子结晶是从熔体先形成中间相，中间相转变为小晶块，最后小晶块融合为均匀为片晶的全新模型。     

固体分层取样方案的最优化设计

本文首次从理论上探讨了取得量对分层取样误差的影响,提出了总取样量一定时各层的最佳取样量和最小取样方差的计算公式,从而为分层取样的最佳取样方案设计提供了理论依据。     

Field sampling demonstration of portable thermal desorption collection and analysis instrumentation

The HAPSITE® (Hazardous Air Pollutants on Site) is a portable gas chromatography-mass spectrometry (GC–MS) unit designed to aid air sampling technicians by identifying and quantifying volatile organic compounds from occupational and environmental sampling. The main goal of the present study was to extend prior laboratory-based work with the portable HAPSITE® ER (extended range model) thermal desorption (TD) capability to real-world field samples from both indoor and outdoor environments using different types of active and passive sampling mechanisms. Understanding the performance of the HAPSITE® ER in a realistic field setting will allow air quality sampling technicians to make improved decisions related to sampling and analysis methods in the field. An important finding was that certain charcoal-based TD sorbents were contraindicated for the HAPSITE® ER because of a substantial hydrocarbon bleed which degraded system performance. A novel time series TD sampler (Logistically Enabled Sampling System-Portable [LESS-P]) was validated using Tenax TA TD tubes against standard active sampling across multiple field sampling sites, and the qualitative analytical trends and compound identities were similar between LESS-P replicates analysed via benchtop GC–MS and HAPSITE® ER. Once validated, the LESS-P was used to determine the reference concentrations for passive sampling calculations. The results confirmed the passive sampling methodology within the benchtop system, but highlighted some systemic sensitivity limitations that must be addressed in order for the HAPSITE® to be accurately applied to passive sampling. We propose that the LESS-P time-series sampler may help to alleviate the requirement for sampling technicians to be on-site during active sampling, allowing for automated sampling throughout the duration of a sampling event.     

Solid-phase microextraction under controlled agitation conditions for rapid on-site sampling of organic pollutants in water

An electric drill coupled with a solid-phase microextraction (SPME) polydimethylsiloxane (PDMS) fiber or a PDMS thin film was used for rapid sampling of polycyclic aromatic hydrocarbons (PAHs) in aqueous samples. Laboratory experiments demonstrated that the sampling rates of SPME fiber and thin film can be predicted theoretically. Compared with the SPME fiber, the PDMS thin film active sampler exhibited a higher sampling rate and much better sensitivity due to its higher surface-to-volume ratio and its larger extraction phase volume. The amount of the analytes extracted by the thin film was around 100 times higher than those obtained by fiber, for both 5 min rapid sampling and equilibrium extraction. A new thin film active sampler was then developed for rapid on-site water sampling. The sampling kit included a portable electric drill, a copper mesh pocket, a piece of thin film, and a liner. Laboratory experiments indicated that the sampling remained in the linear uptake phase with this sampler to 8 min for the PAHs. Field test illustrated that this novel sampler was excellent for rapid on-site water sampling due to its short sampling period, high sampling efficiency and durability The thin film sampling kit facilitates on-site sampling, sample preparation, storage and transport. This new sampler is more user-friendly and easier to commercialize than previous samplers.     

Sampling and sampling strategies for environmental analysis

Sampling errors are generally believed to dominate the errors of analytical measurement during the entire environmental data acquisition process. Unfortunately, environmental sampling errors are hardly quantified and documented even though analytical errors are frequently yet improperly reported to the third decimal point in environmental analysis. There is a significant discrepancy in directly applying traditional sampling theories (such as those developed for the binary particle systems) to trace levels of contaminants in complex environmental matrices with various spatial and temporal heterogeneities. The purpose of this critical review is to address several key issues in the development of an optimal sampling strategy with a primary goal of sample representativeness while minimizing the total number of samples and sampling frequencies, hence the cost for sampling and analysis. Several biased and statistically based sampling approaches commonly employed in environmental sampling (e.g. judgmental sampling and haphazard sampling vs. statistically based approaches such as simple random, systematic random, and stratified random sampling) are examined with respect to their pros and cons for the acquisition of scientifically reliable and legally defensible data. The effects of sample size, sample frequency and the use of compositing are addressed to illustrate the strategies for a cost reduction as well as an improved representativeness of sampling from spatially and temporally varied environmental systems. The discussions are accompanied with some recent advances and examples in the formulation of sampling strategies for the chemical or biological analysis of air, surface water, drinking water, groundwater, soil, and hazardous waste sites.     

二元颗粒混合物按质量取样的误差研究

二元颗粒混合物的随机取样方式有两种：一是按颗粒数目取样,二是按质量取样本文对二元颗粒混合物按质量取样的误差进行了深入研究,详细分析了混合物的各种参对被测组分含量取样误差的影响,应用Ｍｏｎｔｅ Ｃａｒｌｏ技术对取样进行了模拟。以颗粒药品的二元混合物为例对按颗粒数目取样和按质量取样的误差进行了比较。此项研究对于分析取样理论和应用具有重要的价值。     

探讨二元颗粒混合物取样误差的新的数学模型

采用新的数学模型研究二元颗粒混合物的取样误差,首次提出了取样的逻辑质量单元的理论,探讨了逻辑质量单元的物理意义,建立了按质量取样的标准偏差的计算公式.应用颗粒药品二元混合物的取样实验,证实了该公式的正确性.     

Quality-In(Process)Line (QuIProLi) process intensification for a micro-flow UV-photo synthesis enabled by online UHPLC analysis

Process intensification commonly enables reaction acceleration and therefore continuous-flow/PAT is urgently needed. The low volumes typical for micro-flow pose challenges for online sampling operations in analytics. In this paper, a very fast process is combined with a modified ultra-high-performance liquid chromatography (UHPLC) system allowing for very fast sampling and analysis. Low-volume online sampling according to the needs posed by PAT for pharma quality control, is introduced here for UHPLC analysis of the photo-Claisen rearrangement in micro-flow. Chances and challenges are critically reviewed, including the reproducibility and robustness of the sampling. Furthermore, the ability and speed of the chosen set-up in order to capture process changes and adjust the process parameters properly is investigated. With the applied online sampling system, it was possible to perform, almost unattended and spending 12 times less sampling volume, a full factorial analysis of all relevant reaction conditions (243 experiments) in three days. Such quality-in-the-process-line (QuIProLi) online sampling avoided random errors due to automation.     

Improvements to the distance geometry algorithm for conformational sampling of cyclic structures

Modifications to the distance geometry algorithm as embodied in the program DGEOM have been made to improve sampling capabilities. Specifically, torsion angle sampling replaces distance sampling for 1,4 atomic relationships and correlated distance sampling is disabled. The effects of these modifications are illustrated by comparing the different sets of conformations produced for butane. In addition, these changes are shown to increase the conformational sampling of two medium-sized rings, cycloheptadecane and caprylolactam. The current results for these molecules are compared to those of other conformational searching methods.     

Uncertainty of sampling in chemical analysis

 Uncertainty of sampling is the contribution from sampling errors to the combined uncertainty associated with an analytical measurement when the measurand is the concentration of the analyte in the 'target', the total bulk of material that the sample is meant to represent. Of the errors considered to contribute to uncertainty, random errors of sampling, characterised by precision, are much more accessible to investigation than those due to bias. Where an approximation to random sampling can be achieved, realistic precisions can normally be estimated. In some instances reproducibility precision is significantly greater than repeatability precision, and the contribution of between-sampler variations to sampling uncertainty must be acknowledged. However, the collaborative trial of a sampling method is an expensive and difficult exercise to execute. A system of internal quality control for routine sampling can be introduced. Fitness for purpose has been defined in terms of the required combined uncertainty of sampling and analysis. Received: 4 November 1997 · Accepted: 26 November 1997