Identification of factors that accelerate hydrogen production by Clostridium butyricum RAK25832 using casamino acids as a nitrogen source

The ability of Clostridium butyricum RAK25832 to use casamino acids as a nitrogen source was investigated. Strain RAK25832 showed the capacity to utilize different types of carbon sources. With glucose as a carbon source (10 g/L), the preferred final concentration of casamino acids was 26.67 g/L, with a cumulative hydrogen production, production rate, and yield of 2505 mL H₂/L, 160 mL/h, and 1.81 mol H₂/mol glucose, respectively. Eighteen metal elements were screened to identify the most important metals for biohydrogen production, and four elements were optimized. The optimal medium composition was MgCl₂·6H₂O (0.1 g/L), K₂HPO₄·3H₂O (6.67 g/L), NaHCO₃ (2.6 g/L), and FeCl₂·4H₂O (0.002 g/L). Vitamin supplementation of the medium showed no significant effect on hydrogen production. Under the optimized conditions, cumulative hydrogen production reached 3074 mL H₂/L. This is the first study to demonstrate the use of casamino acids as a nitrogen source by C. butyricum.     

DTPA、EDTA氨基安替比林衍生物的合成及其金属配合物的弛豫性能研究

二乙三胺五乙酸(DrrPA)酸酐和乙二胺四乙酸(EDTA)酸酐与4-氨基安替比林(4-AAP)反应，合成了含氨基安替比林的配体DTPA-4-AAP和EDTA-4-AAP，并分别合成了与Gd(Ⅲ)、Fe(Ⅲ)、Mn(Ⅱ)的配合物，配体和配合物用IR、^1HNMR与元素分析做了结构表征。测定了配合物的体外弛豫效率，获得了较好的结果。     

Oxidative stability of milk drinks containing structured lipids produced from sunflower oil and caprylic acid

Milk drinks containing 5% traditional sunflower oil (SO), randomized lipid (RL) or specific structured lipid (SL) (both produced from SO and tricaprylin/caprylic acid) were compared with respect to their particle size, viscosity and oxidative stability during storage. Furthermore, the effect of adding potential antioxidants EDTA or gallic acid to the milk drink based on SL was investigated. The lipid type significantly affected the oxidative stability of the milk drinks: Milk drink based on SL oxidized faster than milk drink based on RL or SO. The reduced oxidative stability in the SL milk drink could not be ascribed to a single factor, but was most likely influenced by the structure of the lipid and differences in the process applied to produce and purify the lipids. EDTA was a strong antioxidant, while gallic acid did not exert a distinct antioxidative effect in the milk drink based on SL.     

EDTA/CA对加氢处理催化剂性能的影响

以碱式碳酸镍、三氧化钼、磷酸为原料制备钼镍磷浸渍液，并在浸渍液中分别添加乙二胺四乙酸、柠檬酸、柠檬酸和乙二胺四乙酸，制备出含单一络合剂及双络合剂的加氢处理催化剂。通过XRD、HRTEM、H2-TPR、NH3-TPD等对其进行表征，发现双络合剂催化剂与单络合剂催化剂相比，降低了活性金属与载体的相互作用力，有利于形成更多的II类活性相，且片晶长度更长，片晶层数更多；同时又具有较大的比表面积和孔容，酸量及中强酸也得到增加。因此，双络合剂催化剂具有更高的加氢脱硫、脱氮活性。     

碱性锌-钴合金镀液中锌、钴含量的测定

为获得耐蚀性良好的锌 钴合金镀层 ,必须维持镀液中的锌 钴含量在工艺范围内。采用EDTA滴定和分光光度相结合的方法测定碱性锌 钴合金镀液中的锌、钴含量。介绍了该方法的分析步骤 ,探讨了测量波长的确定 ,亚硝酸钠、镀液共存组分、酸度以及铜离子和铁离子等杂质对测量结果的影响。结果表明 ,在 530nm波长下 ,钴浓度在 0 - 3μg/mL范围内所测吸光度与钴浓度间的关系遵守比耳定律 ,该方法准确度高 ,回收率达 97% - 1 0 3 5%。     

藕节鞣质提取工艺

为了找到用超声波法提取藕节鞣质的最佳工艺,用EDTA络合滴定法,以洛黑T指示剂的变色效果作为考察指标,测定提取的鞣质含量。实验结果表明,超声提取藕节鞣质最佳工艺条件为10倍量的80%丙酮溶液,超声提取120 m in,且影响力大小为:溶剂量>提取时间>丙酮浓度。     

Structure and properties of SnS films prepared by electro-deposition in presence of EDTA

SnS thin films were deposited onto indium tin oxide (ITO) glass substrates by constant potential cathodic electro-deposition from aqueous solution containing stannous sulfate, ethylenediamine tetraacetate acid and sodium thiosulfate. The co-deposited potential was explored by cyclic voltammetry and the deposition potential (E) was roughly determined to be more negative than −0.70 V (vs. saturated calomel electrode, SCE). The analysis of the composition of the as-deposited films by X-ray fluorescence spectrometer indicated that stoichiometric SnS films could be obtained under the condition of E = −0.95 to −1.00 V. The films deposited at E = −1.00 V were characterized with X-ray diffraction (XRD), scanning electron microscope (SEM), and their transmission and reflectance spectra were measured. The as-deposited films were polycrystalline SnS compound with orthorhombic crystalline structure and the ratio of Sn and S was nearly 1. The films were uniform and compact with small grains. The direct band gap of the films was estimated to be about 1.10–1.43 eV with an absorption coefficient near the fundamental absorption edge larger than 4 × 10⁴ cm⁻¹.     

螯合铁湿法催化煤气脱硫工业试验

改良螯合铁湿法催化脱硫首次用于焦炉煤气脱硫的工业试验,结果表明本脱硫剂性能稳定,各项工业技术参数均达到工业化设计要求。     

EDTA交换法制备脑灌注显像剂99Tcm-ECD--反应条件研究

用脂溶性分数和放射化学纯度两项指标,系统地观察了以ＥＤＴＡ作为交换配体（转移螯合剂）时,制备脑灌注显像剂＾９９Ｔ制剂的反应条件及其稳定性。结果表明,用ＥＤＴＡ交换法标记＾９９Ｔｃ＾ｍ－ＥＣＤ时,放射性浓度对标记影响不大,ｐＨ５￣８范围宽,容易标记,ＥＤＴＡ用量为３６０μｇ和反应体积在２￣６ｍＬ为宜;＾９９Ｔｃ＾ｍ－ＥＣＤ在不同ｐＨ的溶液中可稳定保存。