PCB碱性蚀刻废液高效回收铜粉研究

针对PCB碱性蚀刻废液含铜量高、腐蚀性强等特点,在氮气气氛下采用水合肼液相还原制备高质量铜粉,同时实现蚀刻液再生。研究了液相还原气氛、肼与铜离子的摩尔比、反应温度和反应时间等对沉铜效率以及产物组成的影响。通过电感耦合等离子体质谱(ICP)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)和激光粒度分析仪(LDPA)等对蚀刻液成分、产物物相、形貌结构以及铜粉粒度分布进行表征。实验结果表明:空气气氛下液相还原过程中易产生一价铜,导致产物不纯且沉铜率较低;氮气气氛下肼还原效率显著提高,当肼与铜离子摩尔比≥0.64∶1.00、温度≥90℃时,沉铜率高达99.9%,还原产物以单质铜为主,伴有少量CuCl和Cu_(2)O杂质。经碱洗转化、氢还原后得到的铜粉产品纯度不低于99.9%,粒度均匀,满足工业质量标准。

Mesoporous Ti-Mo Mixed Oxides Catalyzed Transformation of Carbohydrates into 5-Hydroxymethylfurfural

Mesoporous Ti-Mo mixed oxides were prepared via a facile approach using stearic acid as the template, and were characterized using XRD FT-IR, nitrogen adsorption-desorption isotherm and TEM techniques. The catalytic activity of the prepared mesoporous Ti-Mo mixed oxides was first evaluated for the dehydration of fructose to 5-hydroxymethylfurfural(HMF), and a 50.3% yield of HMF was obtained within 60min at 120℃. Moreover, moderate yields of HMF could also be achieved from glucose and sucrose. The mesoporous catalyst could be simply separated from the reaction mixture after termination of the reaction and reused five times with no significant loss of catalytic activity.

内生贪铜菌的分离鉴定及其对铜污染含羞草生长的影响

【目的】研究贪铜菌及其与含羞草(Mimosa pudica)形成的共生体对重金属铜污染的抗性,为重金属污染环境的微生物修复提供参考,丰富功能菌株资源库。【方法】自含羞草根瘤中分离得到菌株HXC-8,扩增该菌株的16S rDNA序列,对其进行鉴定,并对其进行生理生化特性测定,研究菌株HXC-8对重金属铜的耐受性及去除率。此外,设置接菌组(含羞草种子在HXC-8菌悬液中浸泡6 h、自然阴干1 h)和未接菌组(含羞草种子在蒸馏水中浸泡6 h、自然阴干1 h),将2组含羞草种子在Cu^(2+)质量浓度分别为0,50,100,150,200,250,300,350,400 mg/L的混合营养液中培养,分析菌株HXC-8对铜胁迫下含羞草种子萌发和幼苗生长的影响。【结果】16S rDNA基因序列分析结果显示,菌株HXC-8为贪铜菌属(Cupriavidus sp.)细菌,将其命名为“贪铜菌HXC-8”。生理生化特性测定结果显示,贪铜菌HXC-8为革兰氏阴性菌,能分泌活性较高的H_(2)O_(2)酶和淀粉酶,不产生纤维素酶,不适合在肉汁培养基上生长,在糖代谢过程中无混合酸发酵,属于快生型内生菌。随着Cu^(2+)质量浓度的升高,贪铜菌HXC-8的生长受到了抑制,该菌对Cu^(2+)的耐受量是0~150 mg/L。当Cu^(2+)质量浓度为25~150 mg/L时,随着菌液中Cu^(2+)质量浓度的增大,贪铜菌HXC-8对铜的去除率逐渐降低,其中Cu^(2+)质量浓度为25 mg/L时,贪铜菌HXC-8对铜的去除率最高,为97.93%。在0~400 mg/L Cu^(2+)胁迫下,随Cu^(2+)质量浓度的升高,未接菌组和接菌组含羞草种子萌发率均无显著变化,但种子活力指数明显下降;未接菌组和接菌组含羞草幼苗鲜质量、根长、茎长及株高均明显降低。当Cu^(2+)质量浓度为0~300 mg/L时,接菌组与未接菌组含羞草幼苗鲜质量、根长、茎长、株高均无显著差异;当Cu^(2+)质量浓度为350~400 mg/L时,接菌组幼苗以上指标均明显大于未接菌组。【结论】贪铜菌HXC-8对铜具有一定的耐受性,能够降低环境中游离态的Cu^(2+),可减缓重金属铜对含羞草生长的胁迫。

Extraction of Neodymium by Emulsion-Liquid-Membrane within Hollow-Fiber-contactor and Its Mass Transfer Properties

A non-dispersive extraction technique, using an emulsion liquid membrane within a hollow-fiber-contactor for the extraction and enrichment of Nd^3＋ from the dilute feed aqueous, was applied. The emulsion system is consisted of span80 [ sorbitian monooleate], paraffin oil, D2EHPA [ 2-（ 2-ethylhexyl- phosphonic acid）], kerosene as well as HCl solution. The extraction under various conditions such as the span80 concentrations, the flow rate of aqueous, the extraction time and HCl concentrations in receiving phase were studied. Results show that the lower the flow rates of aqueous are, the higher the extraction percentage and enrichment-fold are, and the extraction percentage increases with the increasing of HCl concentrations. When the initial Nd^3＋ concentration in feed is maintained at 1000 mg· L^-1 and the emulsion is recycled with 70 times by a counter-flow,

Alkali Induced Morphology and Property Improvements of TiO_2 by Hydrothermal Treatment

Alkali induced morphology and property improvements of TiO2 by hydrothermal reaction were investigated. The products were characterized by SEM, TEM, XRD, TG, EDX, FT-IR and DRS. The results indicate that, with the phase transformation from anatase to rutile, the morphologies changed from high aggregated particles to nanofibers with the diameter of about 100 nm and the length up to several tens of micrometers, meanwhile the process is controllable by manipulating the nature of the alkali, alkalinity and hydrothermal temperature. DRS analysis shows the property improvement of the nanofibers in the UV-Vis light absorption compared with the raw materials, implying the products have potential application in photocatalysis.

集中式储能电站机电暂态建模及自适应附加功率控制方法

目前的储能建模研究大都关注其电磁仿真模型,难以用于大规模储能接入对系统稳定性的影响研究。该文提出了集中式储能电站的机电暂态建模方法,在电力系统分析综合程序PSASP的用户自定义(UD)模块中搭建了考虑限幅和附加功率控制的储能机电暂态仿真模型。在此基础上,提出了储能电站的自适应附加功率控制方法,并搭建了相应控制模块。不同工况下的仿真结果证明,所提模型能够准确模拟储能对电力系统的暂态支撑,所提自适应附加功率控制方案进一步提升了储能电站对系统的暂态支撑能力。

Minimizing chemical interference errors for the determination of lithium in brines by flame atomic absorption spectroscopy analysis

Chemical interferences （ionization and oxide/hydroxide formation） on the atomic absorbance signal of lithium in FAAS analysis of brine samples are elaborated in this article. It is suggested that inadequate or overaddition of deionization buffers can lead to loss of sensitivities under particular operating conditions. In the analysis of brine samples, signal enhancing and oxide/hydroxide formation inducing signal reduction resulting from overaddition of deionization buffers can be seen with varying amounts of chemical buffers. Based on experimental results, the authors have arrived at the optimized operating conditions for the detection of lithium, under which both ionization and stable compound formation can be suppressed. This is a simplified and quick method with adequate accuracy and precision for the determination of lithium in routine brine samples from chemical plants or R＆D laboratories, which contain comparable amounts of lithium with some other components.

不同乳化剂对姜黄素乳液理化稳定性的影响

姜黄素具有许多生物活性功能,但较差的溶解度和稳定性限制了其在食品和医药领域的应用。为筛选出具有良好稳定性的姜黄素乳液,本研究以亚麻籽油为姜黄素的油相载体,经高压均质法制备出姜黄素乳液中研究卵磷脂、吐温-80、阿拉伯胶和乳清分离蛋白4种食品级乳化剂对姜黄素乳液的理化特性和贮藏稳定性的影响,从包埋率、浊度、粒径、电位等方面进行稳定性评价。结果表明,吐温-80稳定的姜黄素乳液中姜黄素包埋率较高(76.98%),浊度和平均粒径最小,分别为848.0 NTR、214.23±1.52 nm;同时在贮藏期内姜黄素乳液的平均粒径变化最小,增长不到1%,贮藏稳定性表现良好。同时,4℃低温条件下姜黄素保留率最高,达到88.02%。结果表明,选用吐温-80作为乳化剂,姜黄素乳液具有最好的溶解性和稳定性,这为今后姜黄素在食品工业中的广泛应用提供了新思路。

ZrOCl_2·8H_2O: An Efficient and Cheap Catalyst for Esterification of Free Fatty Acids to Methyl Esters

The esterification of lauric acid with methanol could be efficiently catalyzed by ZrOCl2·8H2O, and this reaction was studied to develop a green method for biodiesel production. The influencing factors, such as amount of catalyst, reaction time and molar ratio of acid to methanol, were investigated. The results indicated that the ZrOCl2·8H2O catalyst showed high catalytic activity, and gave a 97.0% methyl laurate conversion rate under the following optimized conditions, viz.: a lauric acid/methanol molar ratio of 1:10, a catalyst dosage of 4%, and a reaction duration of 2 h at methanol refluxing temperature. The catalyst could be easily recovered while its activity could be well retained after three cycles. The ZrOCl2·8H2O catalyst also exhibited excellent catalytic activity for the esterification of different free long-chain fatty acids(including nonedible oils with high acid value) with different short carbon chain alcohols. Therefore, the ZrOCl2·8H2O catalyst has good potential for the synthesis of biodiesel from low-cost feedstocks such as waste vegetable oils and non-edible oils.

1例老年糖尿病高渗性昏迷病人的护理

糖尿病高渗性昏迷(HNDC)高发于60~80岁的老年2型糖尿病病人,是临床常见的急、危、重症。此病来势凶险,病死率高,可达40~60%[1]。老年人由于年龄的增长、机体功能的退化,全身各个系统相继出现问题,处于一个多疾病共存的状态。不同疾病之间因病理、生理、治疗原则、药物禁忌等原因,可能存在相互影响、相互牵制、相互抵触,加大了老年病人疾病治疗的难度,导致老年病人在疾病过程中存在难好转、难治愈、易恶化的特点,对病人的预后及生存质量产生巨大的威胁。

Minimizing chemical interference errors for the determination of lithium in brines by flame atomic absorption spectroscopy analysis

Chemical interferences (ionization and oxide/hydroxide formation) on the atomic absorbance signal of lithium in FAAS analysis of brine samples are elaborated in this article. It is suggested that inadequate or overaddition of deionization buffers can lead to loss of sensitivities under particular operating conditions. In the analysis of brine samples,signal enhancing and oxide/hydroxide formation inducing signal reduction resulting from overaddition of deionization buffers can be seen with varying amounts of chemical buffers. Based on experimental results,the authors have arrived at the optimized operating conditions for the detection of lithium,under which both ionization and stable compound formation can be suppressed. This is a simplified and quick method with adequate accuracy and precision for the determination of lithium in routine brine samples from chemical plants or R&D laboratories,which contain comparable amounts of lithium with some other components.

慢走丝线切割大导程蜗杆刀具实例

通过分析大后角蜗杆加工刀具在慢走丝线切割机上的编程切割过程,介绍了FIKUS线切割编程软件的应用及慢走丝线切割机在切割大锥度工件时的注意事项及加工过程。

基于ASD-KDE算法的超短期风电出力区间预测

为提高含风电场电网经济调度能力并降低电力系统规划决策的保守性,提出了基于原子稀疏分解-核密度(atom sparse decomposition-kernel density estimation, ASD-KDE)算法的超短期风电出力区间预测模型。该模型应用ASD计算出较为精确的点预测值,并采用粒子群优化正交匹配追踪算法提高原子分解过程的预测实时性。同时针对风电序列不同区域所具有的线性及非平稳特性,构建了衰减线性原子库及Gabor原子库,以期达到自适应分解的效果。再通过对原子分量和残余分量分别进行自预测和BP(back propagation)神经网络预测,获得点预测值。在此基础上,通过对历史风电数据不同区间的划分,构建一维核密度估计模型,逐步滚动获取预测值的置信区间,从而降低了环境变化对预测结果的影响。实际风电场算例验证了所提方法的自适应性、快速性及有效性。

Study on the Host-Guest Interactions Between Tetramethyl Cucurbit[6]uril and Benzimidazole Derivatives

In this paper,^(1)H NMR spectroscopy,isothermal titration calorimetry,X-ray crystallography and other characterization methods were used to investigate the interaction modes of tetramethyl cucurbit[6]uril(TMeQ[6])and three benzimidazole derivatives in an aqueous solution-solid state.The results showed that the aromatic ring moieties in the three derivatives all entered the cavity of TMeQ[6]and their substituents were located at the port of TMeQ[6],forming 1:1 host-guest inclusion complexes.The crystal structures showed that the aromatic part of the benzimidazole derivatives interacted with the cavity of TMeQ[6]via hydrogen bond interactions and the N atoms on the benzimidazole ring formed hydrogen bonds with the carbonyl oxygen of TMeQ[6].The ion-dipole interactions between[ZnCl_(4)]^(2-)and TMeQ[6]formed supramolecular self-assembly entities.

Host-Guest Interactions of Cyclopentanocucurbit[6]uril with Alkyl Imidazolium Hydrochlorides

The host-guest interactions between cyclopentanocucurbit-[6]uril(CyP_(6)Q[6])as host and six alkyl imidazolium hydrochloride as guests(g1,g2,g3,g4,g5,and g6)have been studied by various techniques,such as^(1)H NMR spectroscopy,isothermal titration calorimetry,mass spectrometry,and single-crystal X-ray diffraction analysis.The experimental results showed that CyP6Q[6]formed 1:1 inclusion complexes with each of guests g1-g6.The part of the guest entered the cavity of CyP_(6)Q[6]changes as the alkyl chain increases in length.It can be seen that the length of the alkyl chain plays a key role in determining the mode of host-guest interactions.