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61.
Ling Tan Kipkorir Peter Jing Ren Baoyang Du Xiaojie Hao Yufei Zhao Yu-Fei Song 《Frontiers of Chemical Science and Engineering》2021,15(1):99-108
The rational design of photocatalyst that can effectively reduce CO2 under visible light(l>400 nm),and simultaneously precise control of the products syngas(CO/H2)ratio is highly desirable for the Fischer-Tropsch reaction.In this work,we synthesized a series of CeO2-decorated layered double hydroxides(LDHs,Ce-x)samples for photocatalytic CO2 reduction.It was found that the selectivity and productivity of CO and H2 from photoreduction of CO2 in conjunction with Ru-complex as photosensitizer performed an obvious“volcano-like”trend,with the highest point at Ce-0.15 and the CO/H2 ratio can be widely tunable from 1/7.7 to 1/1.3.Furthermore,compared with LDH,Ce-0.15 also drove photocatalytic CO2 to syngas under 600 nm irradiation.It implied that an optimum amount of CeO2 modifying LDH promoted the photoreduction of CO2 to syngas.This report gives the way to fully utilize the rare earth elements and provides a promising route to enhance the photo-response ability and charge injection efficiency of LDH-based photocatalysts in the synthesis of syngas with a tunable ratio under visible light irradiation. 相似文献
62.
Michael Hausmann Martin Falk Charlotte Neitzel Andreas Hofmann Abin Biswas Theresa Gier Iva Falkova Dieter W. Heermann Georg Hildenbrand 《International journal of molecular sciences》2021,22(7)
In cancer therapy, the application of (fractionated) harsh radiation treatment is state of the art for many types of tumors. However, ionizing radiation is a “double-edged sword”—it can kill the tumor but can also promote the selection of radioresistant tumor cell clones or even initiate carcinogenesis in the normal irradiated tissue. Individualized radiotherapy would reduce these risks and boost the treatment, but its development requires a deep understanding of DNA damage and repair processes and the corresponding control mechanisms. DNA double strand breaks (DSBs) and their repair play a critical role in the cellular response to radiation. In previous years, it has become apparent that, beyond genetic and epigenetic determinants, the structural aspects of damaged chromatin (i.e., not only of DSBs themselves but also of the whole damage-surrounding chromatin domains) form another layer of complex DSB regulation. In the present article, we summarize the application of super-resolution single molecule localization microscopy (SMLM) for investigations of these structural aspects with emphasis on the relationship between the nano-architecture of radiation-induced repair foci (IRIFs), represented here by γH2AX foci, and their chromatin environment. Using irradiated HeLa cell cultures as an example, we show repair-dependent rearrangements of damaged chromatin and analyze the architecture of γH2AX repair clusters according to topological similarities. Although HeLa cells are known to have highly aberrant genomes, the topological similarity of γH2AX was high, indicating a functional, presumptively genome type-independent relevance of structural aspects in DSB repair. Remarkably, nano-scaled chromatin rearrangements during repair depended both on the chromatin domain type and the treatment. Based on these results, we demonstrate how the nano-architecture and topology of IRIFs and chromatin can be determined, point to the methodological relevance of SMLM, and discuss the consequences of the observed phenomena for the DSB repair network regulation or, for instance, radiation treatment outcomes. 相似文献
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64.
摘要:在国内某转炉钢厂采用“留渣 双渣”工艺技术进行脱磷工艺试验。结果表明:随着转炉前期脱磷率不断升高,终点脱磷率不断提高。铁水硅含量对前期脱磷率的影响最大。根据铁水成分,在冶炼前期适当降低供氧强度、降低气固氧比、加入适量石灰及烧结矿,均有利于前期脱磷率的提高。在一倒时每吨钢液加入4~8kg石灰,不影响出钢温度,可提高一倒-终点阶段脱磷率,同时可提高终点脱磷率。从终点的控制效果可知,终点炉渣碱度应保持不小于3.0,炉渣中FeO质量分数在16%~20%,并适当降低终点出钢温度在1610~1630℃,有利于终点脱磷率的提高。通过加强熔池搅拌,促进钢渣反应趋于平衡,有利于终点磷分配比提高,从而可进一步提高终点脱磷率。 相似文献
65.
双滑移取向Cu单晶的循环形变行为──Ⅱ.滑移带和形变带SCIEI 总被引:2,自引:0,他引:2
用光学显微镜和扫描电镜研究了双滑移取向([034],[117])Cu单晶循环饱和后的表面形貌,塑性分切应变幅(γpl)低于10^(-3)时,[034]晶体表面上要为主滑移系的驻留滑移带(PSBs)占据,次滑移只在边缘区域启动,其PSBs细窄(<1μm),体积百分数在1%以下.γpl>10^(-3)时,次滑移开始在试样的中部启动,同时,表面出现二种贯穿晶体的宏观形变带(DBI,DBII),滑移带在形变带内集中.[117]晶体在γpl=4.4×10^(-4)时,双滑移现象已十分明显.γpl>10^(-3)时,表面也形成与前者相似的形变带.DBI的惯习面与主滑移面平行([034]晶体)或接近([117]晶体),DBII的惯习面则与前者垂直,文章讨论了形变带形成的可能原因. 相似文献
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68.
双作用变量叶片泵自动控制系统的机理分析 总被引:1,自引:0,他引:1
文章介绍了一种双作用变量叶片泵自动控制系统,通过电脑控制变频器,改变叶片泵转速,达到粗调目的;电脑控制电液数字阀,起微调作用.蓄能器的利用,进一步增了系统的稳定性. 相似文献
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70.
The catalytic partial oxidation of CH4 to syngas was carried out over an Ni–Mg/Al mixed-oxide catalyst prepared from layered double hydroxide-type precursors. The catalysts were characterized by XRD, TPR, UV-DRS, XRF, BET and CHNS analysis. The effects of the catalyst composition and the calcination temperature on the catalytic performance and the extent of catalyst deactivation were investigated. Ni–Mg/Al oxide catalysts converted CH4 into syngas efficiently with high selectivity. The catalyst performance was strongly related to the Ni particle size and the calcination temperature. The catalysts that were calcined at higher temperature exhibited a better catalytic performance. In conclusion, the NiAl2O4 spinel phase had a positive effect on the stability of the catalyst. 相似文献