SDS水溶液荧光光谱研究

十二烷基硫酸钠(SDS)是一种重要的荧光增敏剂.文章研究发现:SDS水溶液的荧光光谱中,300nm处的荧光峰由亲水基的配位物激发产生;330nm处的光峰则由SDS胶团内的憎水基配位物激发产生.配位物的差异,导致-OH基团出现不同波长的荧光.实验及分析结果为利用SDS荧光增敏特性研究碳纳米管等材料的荧光光谱提供了重要信息.     

Synthesis and Structures of A Series of Novel Rare Earth Transition Metal Sulfates

Seven new rare earth transition metal sulfates were synthesized by hydrothermal reactions under conditions slightly above the critical point of water. Their crystal structures were determined from single crystal X-ray data. The compositions of the new compounds can be represented by two general formulae ： REM （OH） 3 （SO4） and RE2M （OH） 3 （SO4） 2F （H2O） with RE = Gd, Tb, Dy ; M = Ni, Cu. Three different crystal structure types were found for the formula REM （OH） 3 （SO4）. The structures of the new compounds all feature infinite chains of REOn coordination polyhedra, which are connected to chains of CuO6 or NiO6 octabedra. The limited size range of the rare earth cations observed in these compounds is most likely because of interactions between the octabedral chains and the chains of REOn polyhedra. The new compounds are closely related to the known yttrium transition metal sulfates.     

电弧炉短流程冶炼石油套管钢中夹杂物的演变规律

为研究石油套管钢(34Mn6)中夹杂物的演变规律,对钙处理效果进行精准化控制,进行全流程取样分析,通过采用SEM-EDS分析夹杂物形貌和成分,同时结合Aspex夹杂物自动分析仪统计夹杂物的数量、成分和尺寸分布。研究结果表明,LF精炼具有较好的脱硫与脱氧能力;钙处理前,由于渣钢反应的进行,夹杂物数量明显减少,夹杂物成分中SiO₂含量增加;经过钙处理后,夹杂物成分发生显著变化,由MgO-Al₂O₃系转变为MgO-Al₂O₃-CaO系和SiO₂-Al₂O₃-CaO系,夹杂物形貌由尖角夹杂向球状夹杂过渡。在铸坯中,夹杂物数量减少,其成分已偏离液相区,向富CaO区域移动。对钙处理进行优化,通过利用热力学软件FactSage进行计算,得出钢液中钙的质量分数稳定在0.001 3%时对夹杂物的改性效果最佳,钢液中的夹杂物控制较好。     

Effect of Sulfate Ions on YAG Powders Synthesized by Microwave Homogeneous Precipitation

Using Al(NO3)3·9H2O, NH4Al(SO4)2·12H2O, Y(NO3)3 as mother salts, and urea as precipitant, YAG nano-powders were synthesized by microwave homogeneous precipitation. The composition, morphology, and phase transformation of precursor were analyzed by IR, XRD and TEM. The size distribution of YAG powders was characterized using laser diffraction method. The results show that sulfate ions influence the dispersion, composition and morphology of the YAG precursors. The addition of moderate sulfate ions can produce YAG powders with nano size and excellent dispersion at 1100 ℃.     

蒸汽活化改善中温烟气脱硫的机理

用蒸汽处理用于中温烟气脱硫的失去反应活性的脱硫剂可以显著提高钙利用率和脱硫效率。为了探明蒸汽活化机理，借助于成分分析和表观形貌检测，分析了蒸汽处理后的脱硫剂理化特性的变化，用CaO迁移的新观点揭示了中温蒸汽活化提高脱硫剂固硫能力的机理，经过蒸汽活化后，乏脱硫剂颗粒除了发生破碎外，其内部未反应的CaO会与蒸汽水合成Ca(OH）2，继而在体积膨胀作用下迁移到颗粒表面，并在分解温度以下还原和与SO2发生反应，迁移过程还改变了颗粒表层的孔隙结构，改善了SO2与CaO扩散，接触和反应。     

Role of Calcium in the Evolution of Superconductivity in a (La2?xRx)Ba2(CayCu4+y)Oz (R = Y, Er, Gd) System

It has been reported that, by adding equal amounts of CaO and CuO to non superconducting La₃Ba₃Cu₆O _z (La-336), a series of superconductors with nominal compositions La₃Ca _y Ba₃Cu_6+y O _z were prepared with maximum T^on _c 80K. Similar studies on addition of CaO and CuO in nonsuperconducting LaBaCu₂O _z (La-112) resulted into superconducting LaCaBaCu₃O _z (La-1113). To date no attempt has been made to synthesize La₂CaBa₂Cu₅O _z (La-2125) superconducting phase by addition of CaO and CuO to non superconducting La₂Ba₂Cu₄O _z (La-224) system. Also no reports are published to study the effect of replacing larger La³⁺-ions (1.01Å) by smaller rare earth ions viz Y³⁺(0.89Å), Er³⁺(0.91Å), Gd³⁺(0.91Å) on the structural and superconducting properties of (La_2–x R _x )Ba₂(Ca _y Cu_4+y )O _z (LRBCaC); 0.0 x 0.5; y=2x system. In this paper, we report the method of synthesis, structural and superconducting property characterization using X-ray diffraction, oxygen content measurements using iodometry, resistivity measurements using d.c. four probe technique and a.c. susceptibility measurements in the temperature range RT to 15K. Also a comparative study, on the evolution of superconducting phase with Ca-concentration for different rare earth substitutions for LRBCaC system in the context of hole doping mechanism, is carried out.     

从油脂氢化含镍废催化剂生产硫酸镍

采用酸碱法从油脂氢化含镍废催化剂中回收金属镍，可以制得工业级的七水硫酸镍。试验结果表明，废催化剂与１．５ｍｏｌ．Ｌ＾－１硫酸比例为１：３（Ｗ／Ｖ），分三阶段反应，每阶段反应时间１ｈ，镍的回收率可达８０％以上。     

分光光度法同时测定饮料中微量钙,镁

本文研究用偶氮氟磷Ⅰ为显色剂,用分光光度法同时测定饮料中微量钙和镁的方法,得出了合理的试验条件,用于饮料分析,取得了满意的结果.     

Evaulation of irritation potential of surfactant mixtures

Irritation potential of sodium laureth sulfate (SLES) alone, and in combination with lauryl glucoside (LG), polysorbate 20 (PS) and cocoamidopropyl betaine (CAPB) was tested in 13 human subjects. Four main and six sub-formulations were prepared and evaluated. Formulations were applied to the forearm as a 24 h close patch study. Irritation was scored by two different methods using an in vivo clinical protocol based on visual scoring and on the stratum corneum capacitance measurement. Irritation was found to be dose dependent. At 2 mg/patch level ten subjects did not show any skin reaction. At 20 mg/patch level eleven subjects showed a broad range of skin irritation. The highest irritation was observed with the formula that contained SLES, LG, and cocamide DEA together. Among the sub-formulations, cocamide DEA showed the highest irritation grade. A statistically significant correlation was observed between visual, clinical and corneometer scores. It was concluded that the irritation potential of surfactants was related to the total surfactant concentration, application mode, and the thermodynamic activity of molecules in the solution as well as the chemical structure of the surfactant molecules.     

Calcium Sulfate Concentration Influence on Yield and Quality of Tofu From Five Soybean Varieties

A mini-process is described for making tofu from 50-g quantities of soybeans. It was used to compare yield and quality among 5 Minnesota grown varieties (Vinton, Corsoy, Hardin, Stine 2510, Stine 2810) and to determine optimum concentration of the coagulant, CaSO₄. Product yield (wet basis), solids recovery, protein recovery and textural quality (Texture Profile Analysis hardness and fracturability) were optimal at 0.02 N CaSO₄ for all 5 varieties. Negative correlations were found between CaSO₄ concentration and both yield (r =? 0.90 to 1.00) and protein recovery (r =? 0.96 to 1.00) for all varieties.