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861.
862.
《资源节约和综合利用》2010,(4):28-28
据美国《纽约时报》4月7日报道,俄美科学家成功合成了一种拥有117个质子的新元素,它可能就是科学家一直寻找的第117号元素(ununseptium),这将填补目前已被发现的第116号和118号元素之间缺失的“一环”:相关研究沧文将在近期出版的《物理评论快报》。 相似文献
863.
864.
利用ASP以及其他助剂组成的复合引发体系,研究了在50℃下采用水溶液自由基聚合方式,得到了溶解性能好的阳离子均聚物PDMDAAC。考察了pH值、引发剂用量和单体浓度对阳离子均聚物黏度和阳离子度的影响。研究了PDMDAAC作为絮凝荆在油田污水处理中的应用。 相似文献
865.
近几年来我国火灾的严重性已使木材阻燃成为一项紧迫任务.为了提高马尾松胶合板的阻燃性能,以聚氨酯为对象,采用HRR3热释放率系统、HC-2氧指数测定仪等测定了涂覆膨胀型纳米聚氨酯防火涂料的马尾松胶合板的燃烧热释放率和氧指数,分析了纳米SiO2以及各种发泡剂对聚氨酯防火涂料阻燃性能的影响,并分析它们的阻燃机理.结果表明,在聚氨酯防火涂料中加入纳米SiO2,可使涂覆的胶合板燃烧失重和炭化体积明显降低,有效地提高阻燃性能,纳米SiO2用量以3%为宜.加入发泡剂可进一步提高涂料的阻燃效果和氧指数值.复合发泡剂比单一发泡剂效果好.在8种试验方案中,用尿素-双氰胺按1∶3的质量比组成的复合发泡剂阻燃效果最优,在HRR3热释放率系统测试中,涂覆的胶合板着火燃烧时间最长(69 s),达最高热释放率时间最短(130 s),热释放率峰值最低(53.45 kW/m2),氧指数值最高(55). 相似文献
866.
The low-heat-value cornstalk gas produced in the down-flow fixed bed gasifier was tentatively used for methanol synthesis. The cornstalk gas was purified and the technical procedures such as deoxygenation, desulfurization, catalytic cracking of tar, purification and hydrogenation were studied. The catalytic experiments of methanol synthesis with cornstalk syngas were carried out in a tubular-flow integral and isothermal reactor. The effect of reaction temperature, pressure, catalyst types, catalyst particle size, syngas flow at entering end and composition of syngas was investigated. The optimum process conditions and yield of methanol from cornstalk syngas were obtained. The experimental results indicated that the proper catalyst for the synthetic reaction was C301 and the optimum catalyst size was 0.833 mm x 0.351 mm. The optimum operating temperature and pressure were found to be 235癈 and 5 MPa, respectively. The suitable syngas flow 0.9-1.10 mol/h at entering end was selected and the best composition of syngas were CO 10.49%, CO2 8.8%, N2 37.32%, CnHm 0.95% and H2 40.49%. The best methanol yield was 0.418 g/g cornstalk. This study provided the technical support for the industrial test of methanol production from biomass (cornstalk) gas. 相似文献
867.
摘要:硅酸钠、硫酸铝为原料制备了聚硅酸硫酸铝絮凝剂,在此基础上制备了不同Zn/Si摩尔比的聚硅酸硫酸铝锌絮凝剂及不同Mg/Si摩尔比的聚硅酸硫酸铝镁絮凝剂。结果表明:Zn/Si摩尔比和Mg/Si摩尔比是影响絮凝效果的最主要的因素。 相似文献
868.
G. K. Parshetti S. G. Parshetti A. A. Telke D. C. Kalyani R. A. Doong P. Govindwar 《环境科学学报(英文版)》2011,23(8):1384-1393
Agrobacterium radiobacter MTCC 8161 completely decolorized the Crystal Violet with 8 hr (10 mg/L) at static anoxic conditions.
The decreased decolorization capability by A. radiobacter was observed, when the Crystal Violet concentration was increased
from 10 to 100 mg/L. Semi-synthetic medium containing 1% yeast extract and 0.1% NH4Cl has shown 100% decolorization of
Crystal Violet within 5 hr. A complete degradation of Crystal Violet by A. radiobacter was observed up to 7 cycles of repeated
addition (10 mg/L). When the effect of increasing inoculum concentration on decolorization of Crystal Violet (100 mg/L) was
studied, maximum decolorization was observed with 15% inoculum concentration. A significant increase in the activities of laccase
(184%) and aminopyrine N-demethylase (300%) in cells obtained after decolorization indicated the involvement of these enzymes
in decolorization process. The intermediates formed during the degradation of Crystal Violet were analyzed by gas chromatography
and mass spectroscopy (GC/MS). It was detected the presence of N,N,N′,N′′-tetramethylpararosaniline, [N; N-dimethylaminophenyl]
[N-methylaminophenyl] benzophenone, N; N-dimethylaminobenzaldehyde, 4-methyl amino phenol and phenol. We proposed the
hypothetical metabolic pathway of Crystal Violet biodegradation by A. radiobacter. Phytotoxicity and microbial toxicity study showed
that Crystal Violet biodegradation metabolites were less toxic to bacteria (A. radiobacter, P. aurugenosa and A. vinelandii) contributing
to soil fertility and for four kinds of plants (Sorghum bicolor, Vigna radiata, Lens culinaris and Triticum aestivum) which are most
sensitive, fast growing and commonly used in Indian agriculture. 相似文献
869.
Jia Liu Kaiming Peng Xiangfeng Huang Lijun Lu Hang Cheng Dianhai Yang Qi Zhou Huiping Deng 《环境科学学报(英文版)》2011,23(6):1020-1026
Exploration of biodemulsifiers has become a new research aspect. Using waste frying oils (WFOs) as carbon source to synthesize
biodemulsifiers has a potential prospect to decrease production cost and to improve the application of biodemulsifiers in the oilfield.
In this study, a demulsifying strain, Alcaligenes sp. S-XJ-1, was investigated to synthesize a biodemulsifier using waste frying oils as
carbon source. It was found that the increase of initial pH of culture medium could increase the biodemulsifier yield but decrease the
demulsification ratio compared to that using paraffin as carbon source. In addition, a biodemulsifier produced by waste frying oils and
paraffin as mixed carbon source had a lower demulsification capability compared with that produced by paraffin or waste frying oil as
sole carbon source. Fed-batch fermentation of biodemulsifier using waste frying oils as supplementary carbon source was found to be a
suitable method. Mechanism of waste frying oils utilization was studied by using tripalmitin, olein and tristearin as sole carbon sources
to synthesize biodemulsifier. The results showed saturated long-chain fatty acid was difficult for S-XJ-1 to utilize but could effectively
enhance the demulsification ability of the produced biodemulsifier. Moreover, FT-IR result showed that the demulsification capability
of biodemulsifiers was associated with the content of C=O group and nitrogen element. 相似文献
870.
Synthesis and high adsorption and selectivity performance of lead ion-imprinted micro-beads with combination of two functional monomers. 相似文献