用于水处理分析的总有机碳分析仪自校方法

根据计量认证要求，用于计量用的总有机碳分析仪需定期进行检定或自校，制定合理可行的校准方法，并根据标准方法对仪器进行检定，岛津Vcpn型总有机碳分析仪校准结果为：重复性0．98％，零点漂移0．022％，直线性0．12％，相关系数0．9992，绝缘阻抗〉20MΩ，满足校准方法技术要求，根据检定结果，该仪器显示数据准确可靠。     

基于二氧化硫标准物质的烟气分析仪误差测量结果的不确定度评定

本文依据JJF1059-2012《测量不确定度评定和表示》和JJG968-2002《烟气分析仪》计量检定规程,以烟气分析仪示值误差为研究对象建立数学模型,分析仪器示值测量结果重复性标准不确定度、标准气体标称值准确度的标准不确定度、被测仪器分辨力的不确定度对合成不确定度的影响,计算各分量灵敏度系数,并结合实验分析数据,以其作为评定烟气分析仪不确定度的重要参考,以保证测量结果的科学性。     

碳排放连续检测气体分析仪测量结果的不确定度研究

为检测电厂烟气中二氧化碳排放量,依据JJG 968-2002《烟气分析仪检定规程》,利用碳排放连续检测气体分析仪进行实验测量,测得二氧化碳浓度并对测量结果进行评定。文章分析了实验获得测量示值误差的不确定度的原因,并评定了测量结果的标准不确定度和扩展不确定度。     

计数浓度粒度标准物质的研制

液体中粒子计数测量常采用电导法(库尔特法)和光阻法.此类仪器在日常校准或计量检定时,必须使用具有己知颗粒计数浓度的标准物质作为计量标准.本文介绍了粒子计数浓度粒度标准物质的制备方法、定值方法及其不确定度分析方法.     

分压电路方法测量直流高压高阻箱示值误差的测量不确定度的研究

直流高压高阻箱是主要用于检定、校准绝缘电阻表和高阻计的计量标准器.提出电阻分压电路(RVD circuit)测量直流高压高阻箱的方法,同时给出测量原理图和计量标准装置的构成,并对分压组合电路测量直流高压高阻箱示值误差的测量不确定度进行了评定.     

离子色谱法测定玻璃熔窑废气中氟化氢的测量不确定度评定

根据离子色谱法测定固定污染源废气中氟化氢的方法及程序,分析测试过程中不确定度的来源.对各不确定度分量进行评定及合成,计算得出合成不确定度和扩展不确定度.结果表明:标准曲线拟合产生的不确定度是影响测量结果不确定度的重要因素.在日常检测中应规范操作,使用经检定或校准合格的仪器设备和玻璃量器,增加样品和曲线标准系列的测量次数,提高测量准确度.     

聚合酶链反应分析仪校准结果不确定度的评定

聚合酶链反应分析仪(PCR仪)在疾控、机关病毒检测、医院、药厂等多个领域有着广泛的应用。PCR仪器的准确度与校准结果直接相关,有助于计量校准技术的研究,能够保证数据的准确可靠,保持正常的仪器工作状态,同时符合相关实验室认可的要求。因此对PCR仪温度示值误差不确定度的来源进行了分析,并对各不确定度分量进行计算,给出了相应的扩展不确定度。     

煤焦检验设备热电偶检定不确定度评定

简述热电偶的热电偶检定过程,依据JJG351对K型偶进行检定,并依据JJF1059对检定结果的不确定度进行评定。分析检定过程中不确定度的来源及其种类,对不确定度分量、合成不确定度和扩展不确定度进行了评定。     

车轮径向疲劳试验机校准方法及主要测量项目不确定度评定

对车轮径向疲劳试验机转鼓、试验负荷和试验速度进行校准,并对试负荷和试验速度的不确定度进行评定。试验负荷和试验速度校准结果不确定度的要来源为试验机分辨力引入的不确定度、试验机测试重复性引入的不确定度、标测力仪或标准转速表分辨力引入的不确定度。     

车轮弯曲疲劳试验机校准方法及主要测量项目不确定度评定

对车轮弯曲疲劳试验机试验弯矩、加载轴偏移量、试验转速进行校准,对试验弯矩和试验转速的不确定度进行评定。试验弯矩和试验转速校准结果不确定度的主要来源为试验机分辨力引入的标准不确定度、试验机测试重复性引入的标准不确定度、标准测力仪或标准转速表分辨力引入的标准不确定度。     

涂料剖析

简要分析了不同涂料体系分析程序,说明了每种涂料剖析体系中应该注意的事项。     

芒果苷元的人工全合成研究

以2-溴-4,5-二甲氧基苯甲酸(6)和均苯三酚三甲醚(5)为起始原料,经Friedel-Crafts酰基化、选择性脱甲基、Ullmann成醚环合、全部脱甲基四步反应,合成了芒果苷元(1),总收率51%。目标产物经高效液相检测,纯度达99.5%,其结构经IR、MS、1H NMR和13C NMR表征。     

E-白藜芦醇化学全合成

以3,5-二羟基苯甲酸为起始原料,由羟基保护,酯基硼氢化钠还原,羟基氯代制备氯苄,制备了膦酸酯;经Wittig-Horner反应,脱甲基反应合成了E-白藜芦醇。合成总收率达47.6%。     

周期全回流间歇精馏中全采出操作时的塔顶浓度平台期(英文)

The total withdrawal operation is an inevitable section in cyclic total reflux batch distillation.In the operation,an interesting phenomenon "overhead concentration platform"(OCP) appears,which is defined as a period of time with high overhead concentrations when the operation is changed from total reflux to total withdrawal.The OCP phenomenon and its influential factors,such as the theoretical stage number,feed concentration,and feed composition,are examined by simulations and experiments.The experimental equipment is a column with random packings.It is shown that the number of theoretical stages influences the OCP more significantly than the other factors.     

Total synthesis of zoanthamine alkaloids

Zoanthamine alkaloids, isolated from organisms in the Zoanthus genus, constitute a distinctive family of marine metabolites. These molecules exhibit a broad spectrum of unique biological properties. For example, norzoanthamine inhibits interleukin-6, the key mediator of bone resorption in osteoporosis, providing a promising drug candidate for a disease that affects more than 10 million people over age 50 in the United States. In addition, these natural products are characterized by a densely functionalized heptacyclic framework, as exemplified by the structures of zoanthamine, norzoanthamine, and zoanthenol, which makes them extremely attractive targets for chemical synthesis. Prior to our first total synthesis of norzoanthamine in 2004, the densely functionalized and complex stereostructures of the zoanthamine alkaloids had impeded synthetic studies of these molecules. In this Account, we describe our synthetic approach toward the total synthesis of zoanthamine alkaloids, focusing on how we overcame various synthetic challenges. At the beginning of our synthetic studies, we aimed to develop an efficient route that was flexible enough to provide access to several members of the family while allowing the synthesis of various analogues for biological testing. Our first project was the total synthesis of norzoanthamine, and we established an efficient synthetic route based on a novel strategy involving the following key features. First, we used a sequential three-component coupling reactions and subsequent photosensitized oxidation of a furan moiety to synthesize the precursor for the key intramolecular Diels-Alder reaction. Second, the key intramolecular Diels-Alder reaction constructed the ABC-ring carbon framework bearing two adjacent quaternary asymmetric carbon atoms at the C12 and C22 positions in a single stereoselective step. Third, we installed the third quaternary asymmetric carbon center at the C9 position by an intramolecular acylation of a keto alcohol followed by successive O-methylation and C-methylation reactions with complete stereoselectivity. Through the exploitation of a deuterium kinetic isoptope effect, we then efficiently synthesized the alkyne segment. Next, a coupling reaction between the alkyne segment and the amino alcohol segment and several subsequent synthetic transformations afforded the bis-aminoacetalization precursor. Finally, bis-aminoacetalization reactions carried out in one-pot constructed the DEFG-ring system and culminated in the total synthesis of norzoanthamine. Our synthetic route to norzoanthamine also allowed access to other zoanthamine alkaloids from a common synthetic intermediate, by way of stereoselective introduction of the C19 methyl group for zoanthamine, and isoaromatization for construction of the aromatic A-ring in zoanthenol. The chemistry described here not only allowed us to overcome formidable synthetic challenges but also opened a completely chemical avenue to naturally occurring zoanthamine alkaloids and their synthetic derivatives.     

克螨特原药的全分析

采用气相色谱—质谱联用技术，分离和鉴定了克螨特原药标样、工业品及本实验室合成克螨特原药中的杂质，并探讨了其成因。     

全卤制碱新工艺

叙述２０ｋｔ／ａ全卤隔膜法制烧碱工艺;探讨３０ｋｔ／ａ全卤离子膜法制烧碱工艺的两个方案。针对全卤隔膜法烧碱工艺存在４个关键问题提出新的工艺方案并已用于工业生产     

Total desalination of brackish water

With desalination of brackish water far inland, the discharge of the concentrated brine which -is -inevitably produced as a by-product by all the desalination processes may pose a serious problem.

Deep well injection and discharge into rivers can be a solution in many cases. These methods however have serious disadvantages with respect to ecology and a pipeline to the sea can only be considered for shorter distances.

As an alternative, a hybrid plant consisting of a Reverse-Osmosis unit and a crystallization section has been studied. Such a combination converts brackish water into fresh water and a crystal sludge which can be either stored or treated for further use. Because of the scale-forming substances in brackish water, only modified crystallization processes can be employed as second stage of the hybrid plant. In this study, two versions are discussed: agitated thin-film evaporators and a modified MSF-process employing oil as a heat-carrier.

Cost figures for the total process will be given and the sensibility of the fresh-water-price to variations of the main parameters like capacity, fuel price etc. will be discussed.