MSMPR结晶器中肌肉肌醇的冷却结晶动力学

对肌肉肌醇(以下简称肌醇)在纯水中的冷却结晶动力学进行了一定的理论研究。实验测得了不同条件下肌醇晶体的粒数密度分布数据,通过粒数衡算方程,证明肌醇晶体生长过程是与粒度无关的;采用间歇动态法中的矩量变换法建立了肌醇冷却结晶过程动力学方程,利用最小二乘法回归出肌醇结晶过程中的各项动力学参数,得到肌醇晶体的成核速率方程和生长速率方程。实验结果表明,肌醇晶体的成核和生长过程均为吸热过程;在肌醇结晶过程中,成核较生长更容易发生。     

植酸酶

一、项目简介植酸酶是一种能将肌醇六磷酸(植酸)分解成肌醇单磷酸至肌醇五磷酸的一种酶。要想彻底分解肌醇单磷酸和肌醇二磷酸等,需要酸性磷酸酯酶的帮助,酸性磷酸酯酶在植酸彻底分解过程中起重要作用,它可以把肌醇单磷酸、二磷酸彻底分解成肌醇和磷酸。植酸酶作为饲料用酶60年     

肌醇及其应用

一、肌醇的性质肌醇系环己六醇的六羟基环己环,即环己六醇,分子式为 C_6H_(13)O_6,按其立体结构而论,肌醇有八种顺式、反式的立体异构体,而一般肌醇是指内消旋肌醇。肌醇易溶于水,微溶于酒精、冰醋酸、甘油和乙二醇,不溶于乙醚、氯仿、无水丙酮等有机溶剂,肌醇在低于50℃的温度下,可从水中结晶为无色     

植酸的发展概况

植酸是Preffer于1872年发现的,直到1969年才由Tate确定其分子结构。植酸,化学名称为肌醇六磷酸酯,即环己六醇六磷酯,它是肌醇磷酸脂的混合物,包括肌醇二磷脂。肌醇三磷脂、肌醇四磷脂、肌醇五磷脂、肌醇六磷脂等。分子式:C_6H_(18)O_(24)P_4,分子量:     

100t/a肌醇项目的技术经济论证

介绍了肌醇的应用、国内外市场及我国肌醇的原料资源，对１００ｔ／ａ肌醇项目进行了技术经济评价     

磷酸钙瓷器的新原料肌醇渣的提取与利用

以米糠为原料的植酸钙提取肌醇的生产过程中,产生出几乎与原料相当的肌醇渣,肌醇渣为磷酸盐的混合物,主要成分是磷酸钙。当前如何开发肌醇渣的出路,提高肌醇渣的利用价值,成为生产厂十分迫切需要解决的问题。目前肌醇渣作磷肥、矿物质饲料外,还可提取优质磷酸钙,经高温煅烧成羟基磷灰石,可作生物陶瓷的原料,如用于人工骨、人工关节、人工牙齿等,肌醇渣中提取的磷酸钙,还可提供磷酸钙系瓷器的原料。     

肌肉肌醇的应用及市场分析

肌肉肌醇是一种水溶性维生素,是人与动物生长所必需的物质。广泛用于食品、医药、饲料及化妆品等行业。本文在肌肉肌醇的理化性质上,结合肌肉肌醇在我国的生产现状,对各工艺技术要点进行总结;综述了肌肉肌醇的应用领域,可用于治疗肝炎、糖尿病等,可作为营养强化剂,还可促进动物生长并延缓衰老;同时分析了肌肉肌醇的近几年来的市场动态,其中出口量占肌醇产量的大部分,为增强肌醇的回报率,在增大出口的同时还应扩大内需。     

提高肌醇收率的工艺技术研究

肌醇原生产工艺存在收率低(7%)的情况,对肌醇各生产过程进行了改进,肌醇收率达到了9.3%。     

植酸含量的测定─—钒钼黄比色法的方法探讨

植酸含量的测定─—钒钼黄比色法的方法探讨蒋建军（长沙化工研究所·４１０００７）１前言植酸是肌醇磷酸酯混合物，包括肌醇二磷酸酯、肌醇三磷酸酯、肌醇四磷酸酯、肌醇五磷酸脂、肌醇六磷酸酯等。它具有独特的生理药理功能和化学性质，在医药、食品、化学、化工、保鲜...     

技术市场

<正> 一、技术转让 肌醇项目征求接产单位 (五邑大学、佛山大学、中国科学院长沙农业现代化研究所、中国化工学会精细化工专业委员会联合开发肌醇项目组) 肌醇是高级营养补品和贵重药品,又是紧俏的生化原料及渔用医药品。据专家预测,十年内肌醇均供不应求,目前国内肌醇年产量不足800t,90％外销,国际市场价约3万美元/t。我们有合作单位包销或代销,可陪同前往肌醇生产厂考察产、供、销情况。 米糠是提取植酸钙镁生产肌醇的最佳原料。全球1/3以上的米糠是中国出产的,占世界首位。     

An interpretation on the origin of the specular reflectance change caused by the submonolayer formation of foreign metals on some precious metal electrodes

The optical properties of foreign metal submonolayers formed on Au, Ag, Cu, Pt and Pd electrodes through the underpotential deposition have been investigated by specular reflectivity measurement. Based on the spectral characteristics, 14 adsorbate-substrate systems were classified into 2 groups. The first group, involving Bi on Au, Cu on Au, Pb on Au, Tl on Au, Tl on Ag and Cd on Cu, is characterized by the similarity of the optical properties of the adsorbed metal in the submonolayer to those of bulk metal. The first monolayer was found to form through several submonolayer stages, in which the optical constants are slightly different from each other. In the second group, involving Cd on Au, In on Au, Sn on Au, Ag on Pt, Bi on Pt, Cu on Pt, Pb on Pt and Bi on Pd, the spectra of submonolayer observed experimentally differ from those calculated with the assumption that the optical properties of adatom and substrate are the same as those of corresponding bulk metal. The difference in the work functions between adsorbate and substrate materials in this group is larger than those in the first group.From these findings, some considerations were made to interpret the origin of the specular reflectance change due to the presence of metal adlayer on the electrode surface. The results allow a tentative conclusion that the reflectivity change is predominantly attributed to the optical properties of the adsorbed submonolayer, but at the same time the work function of the substrate and the interband transition in visible should also be taken into consideration.     

热镀锌板的镀层成分对其表面电泳漆膜抗石击腐蚀性能的影响

研究了热镀锌板的镀层成分对其表面电泳漆膜抗石击腐蚀性能的影响。结果表明,经过合金化退火得到的GA板镀层中含有一定量的Fe,镀层较未经合金化退火的GI板硬。GA板镀层表面疏松多孔,电泳漆膜能够充满其缝隙或凹陷之处,固化后在界面区产生了类似勾键作用的机械作用力。因此,GA板与电泳漆膜的附着力优于GI板,石击处的扩蚀速率小于GI板。     

聚丙烯酰胺在黑土上的吸附解吸特性研究

采用静态吸附法研究了聚丙烯酰胺在黑土上的吸附行为,考查了不同吸附时间对土壤吸附量的影响,得出了聚丙烯酰胺在土壤上的吸附等温线。并且研究了聚丙烯酰胺在黑土上的解吸行为,探讨了振荡时间、液固质量比、温度、pH值对黑土中聚丙烯酰胺解吸的影响。结果表明,聚丙烯酰胺在黑土上的吸附等温线符合Langmu ir吸附模式,饱和吸附质量比为1.17 mg/g,聚丙烯酰胺在土壤上有很强的吸附亲合力,在实验条件下,最大解吸量仅为总量的25%。     

颜料色浆的选择对外墙涂料耐候性的影响

探讨色浆的选择对外墙涂料色漆耐候性的影响因素。重点讨论色浆类型的选择对性能的影响,同一种颜色用不同的复合色浆对耐候性的影响,色浆与调色基础漆配方设计对耐候性的影响以及墙面基材对保色性的影响。     

甲酸在钛基纳米多孔网状铂电极上的电化学氧化

将水热法和电解过程相结合，制备出一种新型的钛基纳米多孔网状铂电极(nanoPt)，它具有特殊的网络状结构及巨大的表面积. 循环伏安曲线表明,在碱性溶液中，甲酸在nanoPt上的氧化电流密度远远大于在多晶Pt上的电流密度，其氧化峰电流几乎是后者的100倍；恒电位电解时，甲酸在nanoPt上的氧化电流开始时随时间的增加而增加，随后达到稳定，其稳定电流也明显高于多晶Pt；在nanoPt上甲酸的非线性现象出现的电流密度范围要比在多晶铂上的宽. 多次循环扫描和长时间电解实验表明. 这种钛基nanoPt结构稳定，催化剂颗粒不易脱落，有可能作为一种新型的燃料电池阳极材料而得到应用.     

Deactivation of the metal and acidic functions for Pt, Pt-Sn and Pt-Sn-K using physically mixed catalysts

The effect of K addition on the amount and dispersion of carbon deposition on metal sites and support sites was investigated on a physical mixture for hexane dehydrogenation. TPO, BET and ESR experiments were used for characterization. The K addition significantly decreases catalyst deactivation involving the amount of coke deposits and the density of carbon radicals on the metal and support sites because of ensemble and electronic effects, especially on the metal sites. Coke on the metal sites associated with carbonaceous species rich in hydrogen is less polymerized than coke on the support sites, corresponding to a more graphitic-like carbon.     

汽车空调行业ODS替代品的需求与预测

本文对中国汽车空调行业随轿车工业的发展而迅速发展及汽车空调CFC-12替代计划的实施做了简单的介绍,并就汽车空调ODS淘汰过程中的替代品HFC-134a和润滑油的变化进行了分析和需求量的预测。     

三聚磷酸二氢铝对氨气的吸附动力学研究

在真空干燥器中,加入一定量待测气体的水溶液,保持真空干燥器中待测气体浓度恒定。利用此装置研究了氨气浓度、三聚磷酸二氢铝吸附大气和水蒸气后,对三聚磷酸二氢铝吸附氨气动力学的影响。结果表明,三聚磷酸二氢铝吸附氨气,可用一级动力学方程和Elovich动力学方程模型描述;氨水浓度对吸附量和平衡吸附时间有显著影响;三聚磷酸二氢铝吸附空气后,对吸附量和平衡吸附时间无影响;三聚磷酸二氢铝吸附水蒸气后,对吸附量和平衡吸附时间均有影响。     

Methyl Jasmonate Application Induces Increased Densities of Glandular Trichomes on Tomato, <Emphasis Type="Italic">Lycopersicon esculentum</Emphasis>

This study was designed to address whether applications of methyl jasmonate (MJ) or Benzothiadiazole (BTH) to cultivated tomato, Lycopersicon esculentum, induced elevated densities of defense-related glandular trichomes on new leaves. Four-leaf tomato plants were sprayed with MJ, BTH, or control solutions, and the density of type VI glandular trichomes on new leaves was subsequently determined at 3, 7, 14, 21, and 28 d. At 7, 14, and 21 d, the density of type VI glandular trichomes on new leaves was significantly higher on MJ-treated plants than on BTH- or control-treated plants. At 7 and 14 d after treatment, the mean density of glandular trichomes on new leaves of MJ-treated plants was ninefold higher than on leaves of control-treated plants. We observed entrapment of immature western flower thrips in trichomes on MJ-treated plants at higher rates than on BTH or control plants. Studies to evaluate potential trade-offs between reductions in pest populations by increased trichome density and possible negative impacts of trichome induction on biological control agents are needed.     

High performance liquid chromatography of oxygenated cholesterols and related compounds

Twenty-four oxygenated cholesterols and structurally related compounds were analyzed by high performance liquid chromatography with silicic acid column and various mobile phases. Hexane–propanol was superior to hexane/tetrahydrofuran and hexane/ethyl acetate for the separation of oxygenated cholesterols. The retention volumes of oxygenated cholesterols depended on the characteristics of the substituting group, its position of substitution, as well as its orientation. The effect of various functional groups at different positions on cholesterol molecules, in general order of decreasing retention volumes, were: hydroxy on the ring, carbonyl on the ring, epoxy on the ring, hydroxy on the side chain, and carbonyl on the side chain. Synergistic effect of multiple hydroxyl substitutions on cholesterol was observed.