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排序方式: 共有1314条查询结果,搜索用时 15 毫秒
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Emad. M. Elsehly N. G. Chechenin A. V. Makunin H. A. Motaweh E. A. Vorobyeva K. A. Bukunov E. G. Leksina A. B. Priselkova 《中国化学工程学报》2016,24(12):1695-1702
Filtration efficiency of Ni(II) from aqueous solution using pristine and modified MWCNTs filters was investigated as a function of Ni(II) ion concentration, pH, and filter mass. MWCNTs were synthesized by CVD method and modified using two complementary treatments, purification (using a mixture of hydrochloric acid and hydrogen peroxide) and functionalization (using nitric acid). The effect and mechanism of each treatment on the structural integrity of pristine MWCNTs has been studied. Morphology of the pristine and modified filters was investigated by Raman Spectrometry (RS), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Fourier Transform Infrared (FTIR) spectrometry and Thermogravimetric analysis. It was found from Raman spec-tra that the ratio of the intensity of D-band to that of G-band decreased by purification process, and increased by functionalization process. The adsorption mechanism of Ni(II) onto the surface functional groups of modified MWCNTs was confirmed by FTIR spectrum. The filtration results showed that the removal efficiency of Ni(II) is strongly dependent on pH and could reach 85%at pH=8. Also, modified MWCNT filters can be reused through many cycles of regeneration with high performance. Functionalized MWCNTs filters may be a promising adsor-bent candidate for heavy metal removal from wastewater. 相似文献
73.
阐述了游离氯产生的原因及脱氯方法。介绍了新疆中泰化学(集团)股份有限公司华泰分公司通过对脱氯淡盐水pH值进行精细化控制,达到了降低成本、节能降耗的目的。 相似文献
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Abstracts are not published in this journal
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
77.
JM Bhatavdekar DD Patel N Ghosh PR Chikhlikar TI Trivedi TP Suthar SS Doctor NG Shah DB Balar 《Canadian Metallurgical Quarterly》1997,40(7):785-790
Lanepitant is a high-affinity, selective neurokinin-1 receptor (NK-1) and is effective in the dural inflammation model of acute migraine. Lanepitant 30, 80, and 240 mg given orally was evaluated in a double-blind, placebo-controlled crossover study to determine its effect in reducing migraine pain and severity of associated symptoms. Outpatients treated four migraine headaches of moderate or severe pain intensity with study drug according to a randomization schedule. They recorded their pain intensity and severity of migraine-associated symptoms at 30, 60, 90, and 120 min. Although 53 patients were randomly allocated to a treatment sequence, only 40 patients completed all treatments. There was no statistically significant difference in improvement in migraine pain at any time for any of the treatments. Additionally, there was no change in severity of migraine-associated symptoms associated with lanepitant therapy. No adverse events could be attributed to lanepitant. Lanepitant was ineffective orally in treating acute migraine in this trial. This may be due to poor bioavailability during a migraine attack. Alternatively, the neurogenic inflammation hypothesis may not apply to migraine. 相似文献
78.
KB Avraham T Hasson T Sobe B Balsara JR Testa AB Skvorak CC Morton NG Copeland NA Jenkins 《Canadian Metallurgical Quarterly》1997,6(8):1225-1231
Deafness is the most common form of sensory impairment in humans. Mutations in unconventional myosins have been found to cause deafness in humans and mice. The mouse recessive deafness mutation, Snell's waltzer, contains an intragenic deletion in an unconventional myosin, myosin VI (locus designation, Myo6). The requirement for Myo6 for proper hearing in mice makes this gene an excellent candidate for a human deafness disorder. Here we report the cloning and characterization of the human unconventional myosin VI (locus designation, MYO6) cDNA. The MYO6 gene maps to human chromosome 6q13. The isolation of the human gene makes it now possible to determine if mutations in MYO6 contribute to the pathogenesis of deafness in the human population. 相似文献
79.
The effect of compressive deformation testedabove the M_s temperature on the martensitemorphology in Fe-Ni-C alloys has been studied.Inthe Fe-30Ni-0.12C alloy,the M_s temperature is-50℃ The cylindrical specimens werecompressively deformed at -40℃.The strain rateswere 10,20,30 and 40%.X-ray analysis andmetallographic examination showed that nostrain-induced martensite was found.After quench-ing to -53℃,some thin plates and unusualmorphologies of lenticular martensites with bentand/or broken mid-ribs were observed.In theFe-30Ni-0.34C alloy,the M_s temperature is-120℃.Compressive deformation with differentstrain rates were carried out at room temperature.After quenching to the liquid nitrogen temperature,some bent thin plate matensites(unbroken)occur-red.The transformed twins in bent plate were alsobent and nearly parallel to the γ-α'interfaces.Orientation relationship between austenite and bentmartensite has been examined by means of trans-mission electron microscope.It was proved thatthese unusual morphologies are inherent in thecompressive pre-deformed austenite. 相似文献
80.
The effect of various pHs on winged bean and soybean protein-lipid films formation, proximate composition and rehydration capacity were studied. Film can only form within a specific range of pH. Films prepared at high pHs (7.5, 9.0, 10.0 and 11.0) contained higher proportions of proteins, ash and carbohydrate but lower proportion of fat than those at pH 6.7, 2.5 and 2.0. Winged bean and soybean films were found to have different pattern of rehydration, however both tended to absorb more water at high pH. With regard to film formation efficiency, nutritional value (higher protein content) and rehydration capacity, soybean film is better than winged bean film. 相似文献