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排序方式: 共有480条查询结果,搜索用时 46 毫秒
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有机缓蚀剂的量子化学研究 总被引:33,自引:9,他引:24
本文概述了缓蚀剂量子化学研究方面的成果。着重讨论了缓蚀性能与量子化学参数(如HOMO能量,LUMO能量,电荷分布等)以及分子的电荷分布与缓蚀机制间的关系,并分析了质子化作用对分子量化计算结果的影响,最后简述了缓蚀剂研究中使用的量子化学方法。 相似文献
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聚天冬氨酸阻垢性能的研究 总被引:23,自引:0,他引:23
以L-天冬氨酸为原料合成了聚天冬氨酸,采用静态阻垢评定法,锌试剂分光光度法和测定透光率等方法对聚天冬氨酸进行了阻碳酸钙结垢,稳定锌离子和分散氧化铁能力的测定,结果表明:聚天冬氨酸不仅具有良好的阻碳酸钙垢的性能,对锌离子也有一定的稳定作用,而分散氧化铁的能力则均好于聚马来酸和聚丙烯酸,是一种阻垢性能较好的水处理剂。 相似文献
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《Advanced Powder Technology》2023,34(9):104148
During acrylonitrile–butadiene–styrene (ABS) plastic processing, dust explosions could occur in production and transportation. In this paper, the explosion properties and pyrolysis mechanism of ABS dust were studied. The inhibition effects of sodium bicarbonate (NaHCO3) on ABS dust were investigated using the 20-L explosion chamber, Hartmann tube, and G-G furnace. The results demonstrated that NaHCO3 effectively decreased both the ignition sensitivity and the explosion severity of ABS dust explosion by increasing the mass fraction of the inhibitor. Adding 50 wt% NaHCO3 could reduce the explosion hazard to an acceptable level. Combined with an analysis of gas phase products and thermal decomposition behaviour, it was discovered that incorporating NaHCO3 enhanced the heat stability of ABS dust. The decomposition of added NaHCO3 produced a substantial quantity of CO2, consuming many free radicals especially OH• and H•, which further reduced the decomposition temperature of ABS. The inhibitor effectively interrupted the combustion chain reaction and inhibited the propagation of the explosion. The results establish a scientific and operational basis for the prevention and management of dust explosion hazards in the ABS processing field. 相似文献
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《International Journal of Hydrogen Energy》2023,48(25):9333-9343
Producing clean hydrogen energy by water electrolysis is considered as an effective route to solve the current energy and environmental problems. Herein, a facile inhibitor-regulated corrosion strategy is employed to synthesize efficient hydrogen evolution reaction (HER) catalysts. The corrosion inhibitor of D-sodium gluconate (SG) is adopted to slow down the serious reaction of iron foam (IF) in RuCl3 aqueous solution. It is identified that the abundant hydroxy and carboxyl species of SG can compete with Cl? to adsorb on the IF surface to weaken the drastic reaction between Ru3+ and IF, resulting in achieving uniform amorphous RuFe(OH)x corrosion layers composed of nanoparticle aggregations. Owing to the sufficient exposure of active sites and electronic interaction between Ru and Fe sites, the optimized catalyst exhibits excellent HER activity of requiring a lower potential of 91 mV to reach a current density of 100 mA cm?2 and maintains durable operation at 100 mA cm?2 for 30 h without obvious fluctuations. This work supplies a facile inhibitor-regulated corrosion strategy for designing efficient catalysts for water splitting application. 相似文献
476.
新疆某国有大型黄金矿山矿石特点为矿体极度破碎、原生泥和次生泥含量高,载金硫化矿浮选分离精度低,部分载金黄铁矿嵌布粒度微细且结晶程度较差,金的高效回收技术难度大。基于矿石工艺矿物学特性,取消原泥砂分选工艺,开发应用“全粒级粗磨粗选-中矿再磨单独选别-再选产品梯级返回”选矿工艺流程,强化泥质脉石高效抑制和载金矿物有效活化,应用泥质脉石抑制剂XJ-12和微细粒载金黄铁矿浮选增效剂AXJ-1,在原矿Au品位2.19g/t条件下,实验室全流程闭路试验获得Au品位30.30g/t、Au回收率86.28%的金精矿,有效降低细泥对浮选的干扰,提高难选目的矿物可浮性,实现了金的高效回收。 相似文献
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Dr. Lisa Barbaro Dr. Gayathri Nagalingam Prof. James A. Triccas Dr. Lendl Tan Prof. Nicholas P. West Dr. Daniel L. Priebbenow Prof. Jonathan B. Baell 《ChemMedChem》2023,18(1):e202200533
To date, the clinical use of the anti-tubercular therapy bedaquiline has been somewhat limited due to safety concerns. Recent investigations determined that modification of the B- and C-ring units of bedaquiline delivered new diarylquinolines (for example TBAJ-587) with potent anti-tubercular activity yet an improved safety profile due to reduced affinity for the hERG channel. Building on our recent discovery that substitution of the quinoline motif (the A-ring subunit) for C5-aryl pyridine groups within bedaquiline analogues led to retention of anti-tubercular activity, we investigated the concurrent modification of A-, B- and C-ring units within bedaquiline variants. This led to the discovery that 4-trifluoromethoxyphenyl and 4-chlorophenyl pyridyl analogues of TBAJ-587 retained relatively potent anti-tubercular activity and for the 4-chlorophenyl derivative in particular, a significant reduction in hERG inhibition relative to bedaquiline was achieved, demonstrating that modifications of the A-, B- and C-ring units within the bedaquiline structure is a viable strategy for the design of effective, yet safer (and less lipophilic) anti-tubercular compounds. 相似文献