一锅法合成O-甲基-N-硝基异脲

采用尿素、硫酸二甲酯、硝酸、硫酸为原料一锅法合成O-甲基-N-硝基异脲。研究了反应温度、时间、催化剂、原料配比对反应收率的影响,确定了优化的工艺条件:原料配比n(尿素)∶n(硫酸二甲酯)=1.3∶1,温度70℃,催化剂50%硫酸,反应时间4 h,总收率为43%,含量在99%以上。     

Direct transformation of calcium sulfite to α-calcium sulfate hemihydrate in a concentrated Ca-Mg-Mn chloride solution under atmospheric pressure

Massive quantities of sulfite-rich flue gas desulfurization (FGD) scrubber sludge have been generated by coal burning power plants. Utilization of the sulfite-rich sludge for preparing α-calcium sulfate hemihydrate (α-HH), an important kind of cementitious material, is of particular interest to electric utilities and environmental preservation. In the experiment, calcium sulfite hemihydrate was directly transformed to α-HH without the occurrence of calcium sulfate dihydrate (DH). The transformation was performed in a concentrated CaCl2 solution containing Mg2+ and Mn²⁺ at 95 °C, atmospheric pressure and low pH. The oxidation of calcium sulfite and the subsequent crystallization of α-HH constitute the whole conversion, during which the oxidation turns out to be the rate controlling step. Solid solution comprised of calcium sulfite hemihydrate and calcium sulfate was found to coexist with α-HH in the suspension. Calcium sulfate increases and calcium sulfite decreases spontaneously until the solid solution disappears. Thus, it is a potential alternative to utilize sulfite-rich FGD scrubber sludge for the direct preparation of α-HH.     

三种阻垢剂阻硫酸钙垢协同效应的研究

采用电导法研究了聚天冬氨酸（PASP）、羟基亚乙基二膦酸（HEDP）、2-膦酸基-1,2,4三羧基丁烷（PBTCA）三种阻垢剂单组分时的阻CaSO4垢性能以及二元复配、三元复配后的协同效应。考察了pH、温度等条件对二元复配物阻垢性能的影响。实验表明：二元组合除PASP和PBTCA之间存在协同效应,其余组合不存在协同效应...     

酸性镀铜溶液中硫酸铜和锌杂质的分析方法

酸性镀铜溶液中的锌杂质严重影响硫酸铜的测定结果。介绍了硫酸铜和锌杂质的分析方法。用三乙醇胺光度法测定硫酸铜,用EDTA容量法测定硫酸铜和锌杂质的总量,从总量中减去硫酸铜的量得到锌杂质的质量浓度。方法简单,快速而准确,能够满足监控酸性镀铜溶液的要求。     

Porous Y<Subscript>2</Subscript>O<Subscript>3</Subscript> microcubes: synthesis and characterization

In this work, a facile route using a simple solvothermal reaction and sequential heat treatment process to prepare porous Y₂O₃ microcubes is presented. The as-synthesized products were characterized by X-ray powder diffraction (XRD), scanning electronic microscope (SEM), energy dispersive spectrometer (EDS), thermogravimetric analysis (TG), and differential thermal analysis (DTA). The thermal decomposition process of the Y₂O₃ precursor was investigated. SEM results demonstrated that the as-prepared porous Y₂O₃ microcubes were with an average width of about 20 μm and thickness of about 8 μm. It was found that the morphology of the Y₂O₃ precursor could be readily tuned by varying the molar ratio of S₂O₈²⁻ to Y³⁺. Y₂O₃:Eu³⁺ (6.6%) microcubes were also prepared and their photoluminescence properties were investigated.     

十二烷基硫酸钠与铝盐絮凝特征研究

为了更好地去除水体中残留的表面活性剂,选用十二烷基硫酸钠为研究对象,在298．15K时,对临界胶束浓度之上和CMC之下的SDS溶液与典型无机絮凝剂（AlCl3）的絮凝行为进行了实验和理论方面的研究。结果表明：在SDS／AlCl3絮凝体系中,0．01mol／LSDS和0．001mol／LSDS与铝盐达到最佳絮凝时,Al^3＋与SDS的摩尔比（记为CAl／BSDS）分别约为0．5和1．0。最佳絮凝时,体系Zeta电位接近零点,表面张力降到最小,pH值均在4．0以下,电导率随CAl／BSDS呈线性增大变化。在0．01mol／LSDS与Al“絮凝体系中,当凝聚摩尔比G化赫约为21．6时,絮凝体完全消失并不再浑浊,而在0．001mol／LSDS与Al^3＋絮凝体系中观察不到絮凝体完全消失的现象。     

钾盐对氰化镀铜溶液性能的影响

研究了钾盐对氰化镀铜溶液性能的影响,结果表明,向镀液中加30～60 g/L的硫酸钾,能够明显提高镀层的光亮度和镀液的覆盖能力,当采用较低质量浓度氰化镀铜溶液时,硫酸钾能够提高镀液的分散能力.生产实践表明:在挂镀氰化镀铜槽中用硫酸钾取代有机光亮剂能够提高镀层与基体之间的结合力.     

《化学试剂七水合硫酸锌(硫酸锌)》标准修订研究

本文对<化学试剂七水合硫酸锌(硫酸锌)>国内外标准以及产品生产企业、应用单位的情况进行调研,结合我国实际情况,提出了质量指标、试验方法等方面的修订建议.通过拟定修订标准的质量指标、研究质量指标的试验方法,从中确定最佳方案,最终完成该标准修订文本的起草工作.     

硫酸镓改性离子交换树脂催化合成己酸戊酯

采用硫酸镓与阳离子交换树脂反应制备的改性离子交换树脂为催化剂合成了己酸戊酯。考察了催化剂用量、醇酸物质的量比、反应时间、催化剂重复使用次数及带水剂等因素对收率的影响。结果表明,该催化剂具有催化活性高、易分离回收、重复使用性良好、后处理方便等优势。适宜条件：己酸用量为0.1 mol,醇酸物质的量比为1.4,催化剂用量为0.75 g,反应时间为60 min,甲苯用量为15 mL,收率达97.8%。催化剂使用5次的收率为88.4%。