大颗粒超高纯度硅溶胶的制备及其表征(英文)

采用新工艺路线制备四乙氧基硅烷（tetraethoxysilane,TEOS）,以TEOS为原料制备超纯度大颗粒硅溶胶。TEOS是烷氧基硅烷法制备甲硅烷的副产物,经过精馏提纯以后,加入盐酸或氨水催化剂,采用溶胶-凝胶法制备硅溶胶。结果表明：TEOS和硅溶胶金属杂质离子总含量都低于0.3mg/L。用盐酸催化TEOS水解制备溶胶,胶粒直径达到129nm;用氨水催化,胶粒直径达272nm。当物质的量比n（C2H5OH）/n（TEOS）=6,n（H2O）/n（TEOS）=5,搅拌速度为250 r/min,制备的硅溶胶胶粒均匀度最好。加水不搅拌,胶粒很容易发生团聚,但是,当搅拌速率高于500 r/min时,胶粒出现团聚现象。     

超高纯度VICTREX PEEK聚合物

英国威格斯公司现已推出超高纯度VICTREX PEEK （VICTREX UHP PEEK）材料。VICTREX UHP PEEK是专门制造的聚合物，能够满足清洁室、医药加工与分析化学应用的最严格纯度要求。VICTREX UHP PEEK不仅具有VICTREX标准级别产品的全部力学性能、化学性能、热性能与摩擦性能，而且不含任何可能析出到液体或在真空或高温环境下发生释气的成分。     

关于蒽醌法双氧水纯度问题的探讨

主要对提高双氧水产品纯度，特别是减少产品中碳含量问题进行探讨。     

超高纯度VICTREX PEEK 聚合物为最高纯度定义设下新标准

英国威格斯公司（Victrexplc）现已推出超高纯度VICTREX PEEK （VICTREX UHP PEEK）材料，为聚合物纯度设定了最新标准。VICTREX UHP PEEK是专门制造的聚合物，能够满足清洁室、医药加工与分析化学应用的最严格纯度要求。VICTREX UHP PEEK不仅具有VIC TREX标准级别产品的全部机械性能、化学性能、热性能与摩擦性能，而且不含任何可能析出的液体或在真空或高温环境下发生释气的成分。     

Wacker化学公司将增加超高纯度多晶硅生产能力

该公司将在其德国Nuenchritz工厂新建1万t/a超高纯度多晶硅装置,预定2011年一季度投产,2011年底实现满负荷生产。该项目投资为7．6亿欧元。Wacker化学公司也将进一步扩建德国Burghausen工厂的超高纯度多晶硅生产能力,将从计划扩建0．7万t／a增至扩建1万t／a;加上其他扩建项目,该公司的超高纯度多晶硅生产能力将从目前的1万t／a增大到3．55万t／a。     

影响特级苯纯度的原因分析及应对措施

通过定性定量实验,确定了影响特级苯纯度的主要杂质:环己烷、甲基环己烷、甲苯,并对杂质的性质、来源及分离方法进行研究;分析了工艺上影响特级苯纯度的几个关键操作过程,有针对性地制定了控制粗苯原料质量、提高溶剂质量、稳定加氢系统操作、调整脱重操作指标、调节萃取操作、降低纯苯塔塔底温度等措施;使纯苯纯度由原来的99.90%提高到99.95%以上,质量等级由优等品提高到特等品。     

测定物质纯度新法的探讨

一、前 言 在科学研究和工业生产中,物质纯度的测定要求所使用的方法要简单、快速,试样量要小又能达到一定精度。纯度测定传统的量热计法与现代的差示扫描量热法(即DSC法)相比结果如表。从表中可清楚看出,DSC法具有在达到一定精度情况下既快速、试样量又小的优点,所以得到了越来越多的应用。     

乙苯纯度及烃类杂质的测定方法

中石化长岭分公司乙苯装置采用气相法干气制乙苯技术,生产不小于99.80%的高纯度乙苯。检验中心在Agilent7820A色谱仪上采用聚乙二醇交联毛细管柱对工业乙苯中的微量烃类杂质进行了定性和定量,该方法准确性高,重复性好。经过对比试验和重复性试验,符合标准SH/T 1148-2001要求,本方法同期正式应用于生产中,满足了乙苯装置生产控制的需求,对生产高纯度的乙苯产品的具有非常重要的意义。     

工业用1—丁烯纯度及烃类杂质的测定

介绍HP-AL2O3毛细管柱在工业1-丁烯纯度及烃类杂质测定中的应用,与GB^1相比该法的分离效果更好。     

关于双氧水纯度问题的探讨

一、前言双氧水是一种基础化工原料,广泛地用于化工产品的合成、工业漂白、食品、医药、电子工业等诸多行业。但各种不同的领域,对产品的质量要求不同,根据国家标准,可分为工业级、食品级、医药级、电子级等。其中工业级对质量要求最低,而电子级对质量的要求最高,因此,电子级双氧水也称为超纯双氧水。目前国内外双氧水的生产主要以蒽醌法为主,我国还有电解法生产厂,但成本较高。国外近几年正在大力研究开发氢氧直接合成双氧水方法,DuPont 公司已建成了1.8万吨/年的示范装置。蒽醌法生产的双氧水,在质     

The thermal‐electrical properties of polyvinyl alcohol/AgNO3 films

In this article, one cast technique to fabricate 20–40 wt %AgNO₃‐doped polyvinyl alcohol (PVA) composite films of which electrical resistance sharply dropped (4–5 order) in a certain temperature range was reported. The phase, structure thermal, and electrical resistivity properties of films at different heat treatment temperatures were studied by X‐ray diffraction (XRD), scanning electrical microscopy (SEM) and differential scanning calorimetry (DSC). The results showed that all the AgNO₃ (20–40 wt %) doped PVA films presented an exothermic peak at 182°C. And the temperature of exothermic peak kept constant for various contents of AgNO₃. Meanwhile, the phase composition of the films was greatly affected by the heat treatment temperature. Ag particles were generated during the heat treatment process, and the content of Ag particles increased with increasing the temperature. The resistivity of PVA/AgNO₃ films decreased with increasing the temperature. And a sharp decrease appeared at 155–165°C due to the generation and contact of a mass of Ag particles at this temperature. The thermal‐electrical results suggested the applicability of these materials in temperature sensor, for example, critical temperature resistor thermistor. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Effect of NA-light radiation on the optical gap and crystal structure of AgNO3-diffused PVDF sensor

A casting method was used to prepare polyvinylidene fluoride (PVDF) and 1 wt % MnCl₂-filled PVDF films. AgNO₃ was allowed to diffuse through the filled films. The 3 types of the prepared films were irradiated by Na light with various doses. The post-irradiation and relaxation effects were investigated using ultraviolet–visible spectroscopy, X-ray analysis, and optical microscopy. The results were interpreted on the bases of a theoretical model previously suggested for a build-up and decay of radiation-induced conductivity associated with the transition of charge carriers in the presence of a uniform trap distribution. Various structures were proposed for the diffused AgNO₃ before and after irradiation. It was found that the induced change in optical gap, due to 5-min irradiation time for the AgNO₃ diffused films, exhibits no relaxation phenomenon. Accordingly, this film can be used in photorecording applications. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 1759–1767, 1998     

Physical properties and β-phase increment of AgNO3-filled poly(vinylidene fluoride) films

X-ray diffraction (XRD), infrared (IR) transmition and optical absorption (OA) spectra, differential thermal analysis (DTA), dc electrical resistivity (ρ), magnetic susceptibility (χ) and electron spin resonance (ESR) of AgNO₃-filled poly(vinylidene fluoride) (PVDF) films, were measured over the filler mass fraction range 0.001 ≤ W ≤ 15%. XRD and IR analysis evidenced the increase of α- and β-PVDF crystalline phases due to the AgNO₃ filler. The maximum crystallinity increment was found at W = 0.5%. Three endothermic peaks were detected by DTA, and were attributed subsequently to: the first order para–para-electric phase transition, the first-order ferro-para-electric phase transition and the melting. The melting peak was used to calculate the order of reaction and the activation energy of melting. The observed OA peaks and/or plateau were attributed to the charge-transfer complex formed mainly by the AgNO₃ filler. This assumption was supported by the diamagnetic susceptibility detected for the present system. The temperature dependence of ρ was explored according to a previously proposed one-dimensional interpolaron-hopping model. The hopping distance was formulated numerically as a function of temperature and filling level. The ESR findings were attributed to the roles of AgNO₃ and dimethylformamide solvent in complex formation. Copyright © 2004 Society of Chemical Industry     

小波分解用于硝酸银标准溶液的标定探讨

使用GB601-2002方法配制硝酸银标准溶液时,根据记录的标液滴加量V和对应的溶液电位数(mV),尝试使用小波分解处理数据,以确定滴定终点并计算待标定硝酸银标液的浓度。计算结果与使用二级微商法计算的结果作了对比,经统计检验,有95%的把握认为两种方法所得结果无显著差异。     

煤基载银抗菌剂的研制

研究了以煤为载体、用液相交换吸附法制备煤基载银抗菌剂的实验工艺,探讨了处理温度、处理时间、处理剂浓度等因素对抗菌性离子含量的影响,并找出最佳反应条件为:温度50℃～60℃,时间1h,硝酸银溶液质量浓度0.2mol/L～0.5mol/L。测试了煤基载银抗菌剂的耐洗涤性,同时使用能量色散谱对煤中各元素做了定量、定性分析,探讨了抗菌剂的主要性能和特点,预测了其适用范围。     

贫锰矿制取四氧化三锰的实验研究

贫锰矿用硫酸浸出后,对浸出液进行净化除杂,得到纯净的硫酸锰溶液,该溶液加氨水沉淀得到氢氧化锰,过滤后通空气氧化沉淀,洗涤烘干后,得到高纯度、高比表面积的四氧化三锰产品。实验中,对影响浸出、净化除杂、沉淀和氧化制取四氧化三锰各过程的影响因素分别进行了研究,得到最佳的实验条件,可制备高纯四氧化三锰。     

硫双威原药中杂质成分分析

用高效液相色谱/质谱联用技术及紫外光谱法分离并鉴定了硫双威原药中的主要杂质,确定了硫双威原药中的主要杂质为灭多威(杂质1),吡啶盐酸(杂质2),硫双威异构体(E,Z)(杂质3),硫双威异构体(E,E)(杂质4)及硫(杂质5)。     

高纯度异噁草酮原药的制备

以3-氯-2，2-二甲基丙酰氯为原料，经酰化、环合、缩合制得异噁草酮，总收率达到70％以上。采用氯化氢和冷却结晶的方法，使异噁草酮原药的纯度达到95％以上。     

钛酸钡中微量杂质和粒子性质的控制

根据ＢａＴｉＯ３在电子陶瓷行业应用的特点,着重分析了产品中微量杂质和粒子性质对陶瓷性能的影响,并结合生产工艺提出了生产过程中应采取的措施。     

Degradation analysis of A2/O combined with AgNO3+K2FeO4 on coking wastewater

In this work, a coking wastewater was selected and a biochemical A~2/O treatment device for fractional degradation was designed and employed. After each stage of the treatment, the products were analyzed through gas chromatography–mass spectroscopy(GC–MS) to determine their composition. Finally, AgNO_3+ K_2 FeO_4 was used as an advanced deep catalytic oxidation treatment. It was concluded from the analysis that cyclic organics could be degraded and the chemical oxygen demand(COD) was controlled within 50 mg·L~(-1), in line with the target value. Meanwhile, the spectra obtained from the GC–MS were in accordance with the conclusions reached based on the COD. The research results showed that all hard-degradable organics in coking wastewater could be eliminated through the A~2/O bio-membrane treatment and the advanced treatment of making use of K_2FeO_4 as an oxidant and Ag+as a catalyst, the catalytic efficiency with Ag+as a catalyst of K+2FeO_4 was very high. Agcould evidently improve the oxidation capacity of K_2FeO_4 to wastewater in its short stability time, and this is an important innovation.