甲烷液相催化氧化制甲醇的研究新进展

进行甲烷液相催化氧化制甲醇的研究,对于实现天然气的直接转化和利用具有极其重要的战略意义。从反应溶剂、催化剂、氧化剂三方面对甲烷液相部分氧化制甲醇的最新研究进展进行了评述,并展望了该领域进一步研究和开发的方向。     

含钛尾矿制备高硅贝利特硫铝酸盐水泥的研究

分析了含钛尾矿的矿物组成,结合高硅贝利特硫铝酸盐水泥的特点,提出了应用提取氧化钛后的尾矿、低品位铝矾土、含钛石膏制备高硅贝利特硫铝酸盐水泥的全新观点,并对该种水泥的烧结温度,冷却制度,强度及凝结时间等进行了系统的分析和讨论,结果表明它的烧结温度低,凝结时间及强度介于硅酸盐水泥和快硬硫铝酸盐水泥之间,含氧化钛较高的原料对高硅贝利特硫铝酸盐水泥性能没有明显负面影响。     

X射线荧光光谱熔融片法测定铜矿中的主次元素

采用熔融片法制样,使用X射线荧光光谱仪测定了铜矿中的13种主次量元素。为了有效地控制在熔样过程中硫的挥发,重点讨论了熔融制片法熔剂、氧化剂、脱模剂的选择及用量,预氧化及熔融温度和时间的选择。对分析元素谱线选择、基体效应和谱线重叠干扰校正等也作了详细讨论。实验表明,熔片制备过程中加入氧化剂硝酸锶既可使坩埚避免被腐蚀,又可准确测定铜精矿中的S,氧化效果最佳。此外,采用Sr作为测量铜元素的内标,分析结果的准确度和精密度均得到很好改善。X射线荧光光谱熔片法测定铜矿中的主次元素结果与参考值一致,表明该法能够有效应用于铜矿中主次元素的测量。     

High performance quasi-solid-state dye-sensitized solar cells based on poly(lactic acid-co-glycolic acid)

A stable quasi-solid-state dye-sensitized solar cell (DSC) with a novel amphiphilic polymer gel electrolyte (APGE) based on poly(lactic acid-co-glycolic acid) (PLGA) is fabricated. The APGE could be readily prepared by a simple method at low temperature of 50 °C and exhibits a quasi-solid property, high conductivity, and long-term stability. The 20 and 40 wt% APGE-based DSCs show high photovoltaic conversion efficiency of 7.5 and 7.4%, respectively, under AM 1.5 simulated sunlight, which is comparable to the liquid electrolyte-based DSC with the efficiency of 7.6%. The 40 wt% APGE-based DSC maintains 95% of the initial performance after 60 days in practical conditions. It is also noteworthy that the APGE endows with higher short-circuit current density than the liquid electrolyte. Different natures of the APGE from the typical polymer gel electrolytes have been elucidated by the I-V measurements, electrochemical impedance spectroscopy, electrophoretic measurements, and transmission electron microscopy.     

硫氰酸铵法提金工艺研究

以四川某硫化物包裹型金矿石精金砂为原料, 对比研究了氰化法和硫氰酸铵法的提金效果, 考察了氧化剂Fe³⁺和MnO₂在硫氰酸铵浸金工艺中的作用和特点, 并对氰化法和硫氰酸铵法的浸出机理进行了初步探讨和分析。结果表明, 硫氰酸铵法比氰化法有更好的提金效率; 用Fe³⁺作氧化剂的硫氰酸铵浸金法提金效率可达96%。     

乙蒜素合成新工艺研究

以乙硫醇为原料,KI为催化剂,对乙蒜素合成工艺进行了研究,尤其是对关键中间体二乙基二硫醚的合成关键因素优化和探讨.结果表明,投料比为M乙硫醇:MKI:M30％双氧水=1:0.02:0.6,滴加双氧水时间为3 h,滴加完毕后继续反应20 min,其收率可达85％以上,纯度大于99％;而投料比M二乙基二硫醚:M41％稀硝酸...     

亚硫酸钠防印印花糊料的再利用

将亚硫酸钠的防印印花糊料重新用于印花,针对亚硫酸钠本身的还原性,采用氧化剂与亚硫酸钠进行反应,生成物对印花效果不会产生影响。     

Image- and Fluorescence-Based Test Shows Oxidant-Dependent Damages in Red Blood Cells and Enables Screening of Potential Protective Molecules

An increase of oxygen saturation within blood bags and metabolic dysregulation occur during storage of red blood cells (RBCs). It leads to the gradual exhaustion of RBC antioxidant protective system and, consequently, to a deleterious state of oxidative stress that plays a major role in the apparition of the so-called storage lesions. The present study describes the use of a test (called TSOX) based on fluorescence and label-free morphology readouts to simply and quickly evaluate the oxidant and antioxidant properties of various compounds in controlled conditions. Here, TSOX was applied to RBCs treated with four antioxidants (ascorbic acid, uric acid, trolox and resveratrol) and three oxidants (AAPH, diamide and H₂O₂) at different concentrations. Two complementary readouts were chosen: first, where ROS generation was quantified using DCFH-DA fluorescent probe, and second, based on digital holographic microscopy that measures morphology alterations. All oxidants produced an increase of fluorescence, whereas H₂O₂ did not visibly impact the RBC morphology. Significant protection was observed in three out of four of the added molecules. Of note, resveratrol induced diamond-shape “Tirocytes”. The assay design was selected to be flexible, as well as compatible with high-throughput screening. In future experiments, the TSOX will serve to screen chemical libraries and probe molecules that could be added to the additive solution for RBCs storage.     

Gas-phase oxydehydrogenation of ethylbenzene with nitrobenzene by hydrogen transfer catalyzed reaction to produce styrene and aniline

Gas-phase catalytic hydrogen transfer reaction between ethylbenzene and nitrobenzene, to produce styrene and aniline, has been carried out at 360–460°C on amorphous AlPO₄, SiO₂, Al₂O₃, and on a natural sepiolite, as well as on the corresponding 20 wt% supported nickel catalysts. The influence of Cu as a second metal was also studied. Reactions were also carried out without nitrobenzene, under nonoxidative conditions. Catalytic activity under oxidative conditions was always comparatively higher than in nonoxidative conditions. In both cases, styrene yield and selectivity values obtained with support materials directly used as catalysts were better than those obtained with the corresponding Ni or Ni–Cu supported metal catalysts, with the only exception of SiO₂. The best results were obtained when amorphous AlPO₄ was used as the catalyst. The catalytic activity obtained in both oxidative and nonoxidative conditions, was closely associated to acid–base properties of the catalysts studied. Furthermore, a very similar linear correlation between A and E _a known as “compensation effect” was obtained and a common dehydrogenation mechanism was considered for oxidative and nonoxidative conditions. However, without considering the catalyst, nitrobenzene plays an important role as hydrogen acceptor, not only shifting the ethylbenzene dehydrogenation equilibrium but also avoiding secondary reactions by lowering the level of available hydrogen, especially when supported metals are being used as catalysts. This revised version was published online in July 2006 with corrections to the Cover Date.     

涤棉仿丝绸的酸减量和氧化减量处理

采用酸减量和氧化减量对涤棉混纺织物进行仿丝绸处理，分析比较两者的影响因素和处理后的织物性能。结果表明，两种方法均可使织物获得较好的仿丝绸效果，但两种方法中，达同一减量率时，织物的性能差异较大，仿丝效果不同。