稀土元素对提铯离子筛交换性能的影响

对比了提铯离子筛对铯离子与分部稀土元素的交换容量和分配系数;了钕离子对提铯离子交换性能的影响,以及稀土元素存在对提铯离子筛在高效废液中选择性的影响。稀土元素对提铯离子筛的铯离子交换容量有一定的影响,但对铯离子分配系数影响不大;只要选择合适的液固比V：m,基本上可以消除稀土元素的存在对提铯离子筛在高放废液中铯离子选择性的影响。     

球形托卡马克聚变嬗变堆中子学设计

基于对球形托卡马克ST聚变堆的研究,提出了ST聚变嬗变堆的设计概念。对堆芯参数作了初步选择,确定了一组适合于嬗变包层的堆芯参数供中子学计算和结构设计参考,给出了在以嬗变次锕系元素（MA）核废物为目标的一维中子学计算结果。     

混合沉淀法处理冶金及机械行业实验室废液

提出了一种混合沉淀法处理冶金及机械行业实验室废液的新方法.在适量铁(Ⅱ)存在下,用含块粒状氢氧化钙、碳酸钙、石灰石的石灰乳调节至溶液出现浅棕色,再用精石灰乳调节溶液至pH 8.0～9.3,生成金属的微溶氢氧化物、铁氧体、碳酸盐等混合沉淀.结合间歇往复运动,静置沉降6 h,虹吸分离上清液.生石灰中的脉石成分降至2％.并探...     

采用超临界CO2萃取技术提取废次烟叶中的茄尼醇

采用超临界CO2萃取技术提取废次烟叶中的有效成分茄尼醇,以乙醇为夹带剂,研究了萃取压力、萃取温度、CO2的流量、萃取时间、夹带剂的使用、分离温度和原料粒度等方面对萃取效果的影响,并对其中影响较为显著的因素进行了正交试验,通过极差和方差分析确定了萃取体系适宜的工艺条件。萃取压力为20 MPa,萃取温度为45℃,CO2的流量为15 L/h,萃取时间为2 h,夹带剂为95%的乙醇,分离温度为40℃,原料粒度为40~60目。     

Comparative Analysis of VOCs from Winter Melon Pomace Fibers before and after Bleaching Treatment with H2O2

In this study, the trend of Volatile Organic Compounds (VOCs) in dietary fiber samples from the winter melon (Cucumis Melo var. Inodorus, Yellow Canary type) were investigated. This foodstuff, obtained as a by-product of agri-food production, has gained increasing attention and is characterized by many bioactive components and a high dietary-fiber content. As regards fiber, it is poorly colored, but it may be whitened by applying a bleaching treatment with H₂O₂. The result is a fibrous material for specific applications in food manufacturing, for example, as a corrector for some functional and technological properties. This treatment is healthy and safe for consumers and widely applied in industrial food processes. In this study, a method based on headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC-MS) was applied for the characterization of the aromatic profile of the dried raw materials. Furthermore, VOC variation was investigated as function of the bleaching treatment with H₂O₂. The bleached samples were also analyzed after a long storage period (24 months), to assess their stability over time. As a result, the VOC fraction of the fresh raw fiber showed nine classes of analytes; these were restricted to seven for the bleached fiber at t₀ time, and further reduced to four classes at the age of 24 months. Alcohols were the main group detected in the fresh raw sample (33.8 % of the total chromatogram area), with 2,3-butanediol isomers as the main compounds. These analytes decreased with time. An opposite trend was observed for the acids (9.7% at t₀), which increased with time and became the most important class in the 24-month aged and bleached sample (57.3%).     

入境废物原料浸出液毒性试验方法探讨

在分析入境危险废物浸出毒性试验方法的基础上,针对入境废物原料浸出液毒性试验方法,按照我国对危险废物浸出毒性试验方法基本要求内容,对确定的14种浸出物质试验方法进行了探讨,并将该法有效运用于对入境可用作原料的工业品废物环控指标普查的工作之中。     

Radiation and chemical pretreatment of cellulosic waste

RADIATION AND CHEMICAL PRETREATMENT OF CELLULOSIC WASTE. Combination pretreatment of cellulosic wastes such as corn stalk, cassava bark and peanut husk were studied using chemical and irradiation of electron beam. The effect of 2 % NaOH and irradiation at the doses of 100, 300 and 500 kGy on the cellulosic wastes were evaluated by measurement of the glucose yield in enzymatic hydrolysis. Irradiation was carried out with an electron beam machine EPS-300 (Energy 300 kev, current 50 mA). The result shows that the glucose yield were higher by increasing of dose irradiation and treated with 2 % of NaOH especially in corn stalk. The glucose yield of corn stalk were 20 % in untreated samples and increases to 43 % after treated with electron beam irradiation at the dose of 500 kGy and 2 % NaOH. Cassava bark and peanut husk show the glucose yield are only 3.5, and 2.5% respectively. The effect of E-beam current in enzymatic hydrolysis of corn stalk, and preliminary studied E-beam radiation pretreatment of cassava bark are also reported.     

铂纳米棒有序阵列催化电极在被动式直接甲醇燃料电池中的应用

直接甲醇燃料电池(DMFC)具有能量密度高、无需充电、液体燃料添加便捷及环境友好等优点,是新一代便携式移动电源研究热点. DMFC规模应用的主要技术挑战是如何进一步提高电池性能、显著降低成本和可靠延长寿命.催化电极作为 DMFC发电核心和成本的集中体现,其电催化活性和贵金属用量直接影响 DMFC的性能和成本,开发高性能、低成本的催化电极对推进 DMFC实用化进程具有重要意义.特别是在被动式 DMFC中,阴极催化电极不仅需要提高电催化活性和大幅降低贵金属用量,而且还面临内部严重的“水淹”和氧传质受限等问题.近年来,随着纳米技术发展,有序纳米结构已逐渐应用于 DMFC催化电极的构筑中,电池性能得到显著提高.然而,目前的研究主要集中在膜电极纳米有序微孔层、纳米有序改性膜和纳米有序阳极催化电极及其阳极贵金属载量降低等方面,关于阴极催化电极在有序纳米结构以及载量降低等方面的研究相对较少.
　　本文采用模板法直接在微孔层上电沉积定向生长排列有序、直径可控的铂纳米棒阵列,并作为阴极催化电极应用于被动式 DMFC. X射线衍射和透射电镜结果表明,该铂纳米棒结构稳定,表面含有丰富的纳米晶须结构,有利于催化电极比表面积增加和电催化活性提高.不同催化电极上氧还原的极化曲线表明电极性能依下列次序变化：直径为200 nm铂纳米棒阵列电极>100 nm铂纳米棒阵列电极>商业化铂黑催化电极.电池性能表征表明,长度为1–3μm、直径分别为200和100 nm、载量为1.0 mg/cm2的铂纳米棒阵列作为阴极催化电极的 DMFC最大功率密度分别为17.3和12.0 mW/cm2.通过催化电极电化学活性面积和阻抗测试,分析其性能提高的原因可归结于有序排列的铂纳米棒阵列结构提高了电化学活性面积、增强了氧还原电催化活性并促进了阴极氧的传质.     

金属-有机骨架材料用于废水处理

废水中的各种有害物质常常具有生物毒性或致癌性,因此如何高效、节能地处理水体污染是一个亟待解决的重要问题。金属-有机骨架材料(metal-organic frameworks, MOFs)是一种新型纳米多孔材料,具有种类多样性、结构可设计性与可调控性、高比表面积及良好的热稳定性等优点,已成为当前化学、材料学科的一个研究热点, 在多个领域显示出潜在的应用前景,尤其是在分离方面。与气相分离相比,MOFs用于液相分离的研究较少。本文综述了近年来MOFs用于含有染料、药物、醇、芳香族化合物、重金属离子及其他离子的废水处理的研究进展,重点剖析了MOFs的孔结构、骨架电荷及功能性对分离效果的影响,并结合本课题组的研究工作,对这种新型多功能材料在水处理方面的前景和今后的研究重点作了展望。     

钛白废酸低温除杂浓缩的研究

钛白粉是一种白色颜料,其主要成分为二氧化钛(TiO_2),是一种重要的无机化工产品.其生产工艺有硫酸盐工艺和氯化物工艺两种,硫酸盐法的技术比氯化物法简单,可以用于品位低和比较便宜的矿物~([1]).