供氧体在金溶解过程中的作用研究

本文提出供氧体的概念。认为供氧体在溶解金的过程中起着非常重要的作用。指出了用气体供氧体的缺陷，固体和液体供氧体的特点，以及需要严格控制供氧体的用量。     

速干高强淀粉粘合剂的制备

通过对玉米淀粉的改性，研究了制备玉米淀粉粘合剂时糊化剂，氧化剂，络合剂等用量及其它因素对粘合剂性能的影响。确定了工艺流程，最佳反应条件及配方，制得了一种适合瓦楞纸板用的粘合剂，具有性能稳定，无毒，粘合力强，干燥速度快等优点。     

Biologically Active Digests from Pumpkin Oil Cake Protein: Effect of Cross-linking by Transglutaminase

The objective of this study was to show that biologically active hydrolysates can be obtained by simulated human gastrointestinal digestion (HGD) of transglutaminase cross-linked pumpkin oil cake protein (Tg-C) which was previously reported as a potential functional food additive. A two-stage in vitro digestion model system (by pepsin and α chymotrypsin and trypsin, simultaneously) was used to simulate the process of HGD on native and Tg-C major storage pumpkin oil seed/cake protein, cucurbitin (C). The biologically active potential of the digests was evaluated, measuring the angiotensin-converting-I enzyme (ACE) inhibitory and anti-oxidant capacity. The ACE inhibitory activity was determined in both final digests, with IC₅₀ = 0.30 ± 0.04 mg/ml for C and IC₅₀ = 0.28 ± 0.01 for Tg-C. The anti-oxidant potency of the examined proteins was enhanced by the digestion process. The 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation activities and reducing power testing showed that all the hydrolysates act as a radical quencher and reducing agents. Overall, the results showed that the cross-linking by Tg did not influence the digestion process, as well as having no effect on the biological activity of the hydrolysates. These also indicate that Tg-C, if used as functional food additive, after food consumption can be digested and become a source of peptides exerting positive effects on human health.     

硝酸盐作酸法地浸采铀氧化剂的分解机理探讨

从室内试验、现场有关数据分析、理论计算等多角度进行研究,探讨了硝酸盐作酸法地浸采铀氧化剂时的转换机制,在地浸条件下NH4＋-NO2--NO3-体系三氮平衡关系总是向NO3-转化,表现为NO3-的积累.     

Promotion effect of KOH on preparation of dissolved Fe(Ⅵ)

In order to improve the yield and stability of ferrate in solution, dissolved Fe(Ⅵ) prepared with NaOH and KOH respectively was compared in this study. The results showed that KOH is more suitable than NaOH for the preparation of dissolved Fe(Ⅵ) at temperature over 50 ℃. It is found that the dissolved Fe(Ⅵ) prepared with KOH increases quickly at first, and then slowly with the increasing concentrations of OH-and ClO-, while it increases rapidly at first and then decreases rapidly with the increasing dosage of Fe(NO3)3·9H2O. These results are different from that prepared with NaOH. It can be explained that solid K2FeO4 salts can be formed in KOH solution, and it will lower the Fe(Ⅵ) concentration, counteract the decomposition of Fe(Ⅵ), and improve the yield of Fe(Ⅵ). The maximum ferrate concentration is 0.163 mol/L obtained by 100 g/L Fe(NO3)3·9H2O and 6.16 mol/L KOH at 65 ℃. The stability of Fe(VI) is greatly improved due to the hypochlorite existed in the dissolved ferrate, and only 24% Fe(Ⅵ) has been decomposed after 16 d for 1 mmol/L Fe(Ⅵ) at 25 ℃.     

Promotion effect of KOH on preparation of dissolved Fe (VI)

In order to improve the yield and stability of ferrate in solution, dissolved Fe (VI) prepared with NaOH and KOH respectively was compared in this study. The results showed that KOH is more suitable than NaOH for the preparation of dissolved Fe(VI) at temperature over 50 ℃. It is found that the dissolved Fe(VI)prepared with KOH increases quickly at first, and then slowly with the increasing concentrations of OH- and ClO~- , while it increases rapidly at first and then decreases rapidly with the increasing dosage of Fe(NO_3)_3·9H_2O. These results are different from that prepared with NaOH. It can be explained that solid K_2 FeO_4 salts can be formed in KOH solution, and it will lower the Fe (VI) concentration, counteract the decomposition of Fe(VI), and improve the yield of Fe(VI). The maximum ferrate concentration is 0. 163 mol/L obtained by 100 g/L Fe(NO_3)_3· 9H_2O and 6. 16 moL/L KOH at 65℃. The stability of Fe(VI) is greatly improved due to the hypochlorite existed in the dissolved ferrate, and only 24% Fe(VI) has been decomposed after 16 d for 1 mmol/L Fe(VI) at 25 ℃.     

Fe(Ⅲ)对染料废水的脱色作用

利用FeCl3.6H2O作为无机絮凝剂和H2O2作为氧化剂对活性蓝染料废水进行了脱色实验。通过改变pH、絮凝剂的用量和高分子电解质的种类,寻求最佳的反应条件。实验结果表明,FeCl3.6H2O的浓度为100 mg.L-1,废水的pH=7时,可以达到100%的脱色效果。同时,阳离子型高分子电解质能有效的增加絮凝剂的脱色效率。当Fe(II)和H2O2在最佳的摩尔比条件下,其初始浓度对脱色率也会产生一定的影响。     

二元氧化剂合成簇状聚苯胺纳米棒及其电学性质

通过自组装法采用二元氧化剂合成了簇状聚苯胺纳米棒,用IR、XRD、SEM和EDX等测试手段对产物的结构和性质进行了表征,讨论了氧化剂对产物形貌及性质的影响和反应的形成机理。结果表明,当苯胺单体与氧化剂K2Cr2O7的浓度比为1∶1时,产物形成的簇状形貌最好。     

某砂岩铀矿床矿石中性浸出性能试验

对某砂岩型铀矿石开展不同O2剂量的中性浸出试验。结果表明,试验矿石中性浸出性能较差,铀浓度基本低于20mg/L,在25.2的高液固比条件下,铀浸出率仅为35.36%~41.85%;前期以六价铀浸出为主,浸出强度与HCO3^-浓度正相关;六价铀基本被浸出后,有O2、无O2的浸出差别明显,但O2剂量在30~200mg/L变化时浸出差别并不显著;相对高的pH有利于形成更稳定的铀酰络合物和降低铀的氧化还原临界电位,但应避免高pH引起碳酸钙沉淀。在地浸生产保持不低于800mg/L的HCO3^-和维持浸出液10~20mg/L的余氧是合适的。     

Effect of inner oxidant on self-propagating high-temperature synthesis of MnZn-ferrite powder

Using KClO3 as an inner oxidant, MnZn-ferrite powder was synthesized by a self-propagating high-temperature synthesis (SHS) process in normal air atmosphere. The effects of the inner oxidant on combustion temperature, combustion velocity, microstructure and the phase of the product were investigated by XRD and SEM,respectively. The results show that a highly ferritized powder can be obtained as well as the highest combustion temperature and the highest combustion velocity when the inner oxidant content m equals 5/4( k -1/6).