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The influence of silica on reaction rates and molecular hydrogen(H_(2))generation during olivine hydrothermal alteration

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Science China Earth Sciences 2024年第1期67卷 222-233页

作者： Ruifang huang Weidong SUN Xing DING Yusheng ZHAO yibing LI Xiuqi SHANG CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China SUSTech Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Institue of Geology Chinese Academy of Geological SciencesBeijing 100037China

Hydrothermal alteration of olivine greatly influences geodynamics and the recycling of volatiles(such as water and carbon)in subduction zones.Silica is an important component of geological fluids,and its influence on the hydrothermal alteration of olivine remains poorly constrained.In this study,we performed experiments at 300–515℃ and 3.0 kbar(1 bar=10^(5)Pa)by reacting well homogenized mixtures of olivine and silica powders with saline solutions(0.5 mol L^(−1)NaCl).Silica greatly influences the reaction pathways,reaction rates,and molecular hydrogen(H_(2))formation during olivine hydrothermal alteration.In experiments at 300℃ and 3.0 kbar with mixtures of olivine and 10 wt%silica,olivine was replaced by serpentine and talc.The proportions of serpentine and talc were determined according to standard curves based on infrared spectroscopy analyses.Around 6.5%serpentine and 12%talc were produced after an experimental duration of 7 days,which had no change after a longer period(14 days).Compared to the kinetics in silica-free systems,the rates of olivine hydrothermal alteration in experiments with 10 wt%silica are much lower.The overall reaction is:4.5Forsterite+5.5SiO_(2),aq+4H_(2)O=Serpentine+2Talc.With the addition of more silica(20 wt%and 40 wt%),olivine was transformed into talc.The rates of reaction were much faster,e.g.,for experiments with olivine and 20 wt%silica,43%of talc was produced after 14 days,which increased to 77%for experiments with 40 wt%silica over the same period.The overall reaction is:3Forsterite+5SiO_(2),aq+2H_(2)O=2Talc.In experiments at 400–505℃ and 3.0 kbar,the promoting effect of silica on olivine hydrothermal alteration was also observed,which is closely associated with a decrease in Gibbs free energies of olivine hydrothermal alteration.At 300℃ and 3.0 kbar,silica decreased H_(2)formed during olivine hydrothermal alteration by around an order of magnitude,resulting in an increase in oxygen fugacity.Based on measured H_(2),we calibrated oxygen fugacities,ranging from 0.96 to 3.41 log un

关键词： Olivine hydrothermal alteration Silica Serpentinization Hydrogen Serpentine

Role of helicity of a-helical antimicrobia peptides to improve specificity

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Protein & Cell 2014年第8期5卷 631-642页

作者： Yibing Huang Liyan He Guirong Li Naicui Zhai Hongyu Jiang Yuxin Chen Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education Jilin University Changchun 130012 China National Engineering Laboratory for AIDS Vaccine Jilin University Changchun 130012 China School of Life Sciences Jilin University Changchun 130012 China The First Hospital Jilin University Changchun 130021 China

A major barrier to the use of antimicrobial peptides as antibiotics is the toxicity or ability to lyse eukaryotic cells. In this study, a 26-residue amphipathic a-helical antimicrobial peptide A12L/A20L （Ac-KWKSFLKTFKSLK KTVLHTLLKAISS-amide） was used as the framework to design a series of D- and L-diastereomeric peptides and study the relationships of helicity and biological activi- ties of o-helical antimicrobial peptides. Peptide helicity was measured by circular dichroism spectroscopy and demonstrated to correlate with the hydrophobicity of peptides and the numbers of D-amino acid substitu- tions. Therapeutic index was used to evaluate the selectivity of peptides against prokaryotic cells. By introducing D-amino acids to replace the original L-amino acids on the non-polar face or the polar face of the helix, the hemolytic activity of peptide analogs have been significantly reduced. Compared to the parent peptide, the therapeutic indices were improved of 44-fold and 22-fold against Gram-negative and Gram- positive bacteria, respectively. In addition, D- and L-diastereomeric peptides exhibited lower interaction with zwitterionic eukaryotic membrane and showed the significant membrane damaging effect to bacterial cells. Helicity was proved to play a crucial role on peptide specificity and biological activities. By simply replacing the hydrophobic or the hydrophilic amino acid residues on the non-polar or the polar face of these amphipathic derivatives of the parent peptide with D-amino acids, we demonstrated that this method could have excellent potential for the rational design of antimicrobial pep- tides with enhanced specificity.

关键词： antimicrobial peptides （AMPs） peptideantibiotics helicity secondary structure diastereomericpeptides specificity therapeutic index

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《中国共产党的一百年》的突破和创新

中共党史研究 2023年第5期 94-106页

作者：黄一兵中共中央党史和文献研究院

中央党史和文献研究院编写的《中国共产党的一百年》(以下简称《一百年》)是第一部着力体现和反映《中共中央关于党的百年奋斗重大成就和历史经验的决议》的党史基本著作,是第一部着力体现和反映习近平总书记在庆祝中国共产党成立一百... 详细信息

中央党史和文献研究院编写的《中国共产党的一百年》(以下简称《一百年》)是第一部着力体现和反映《中共中央关于党的百年奋斗重大成就和历史经验的决议》的党史基本著作,是第一部着力体现和反映习近平总书记在庆祝中国共产党成立一百周年大会上重要讲话精神的党史基本著作。

关键词：中央党史重要讲话精神突破和创新一百年中国共产党重大成就中共中央习近平总书记

Transparent characterization and quantitative analysis of broken gangue's 3D fabric under the bearing compression

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International Journal of Mining Science and Technology 2022年第2期32卷 335-345页

作者： Junmeng Li Yanli huang Shenyang Ouyang Yachao Guo Huadong Gao Laiwei Wu yibing Shi Lei Zhu State Key Laboratory of Coal Resources and Safe Mining School of MinesChina University of Mining&TechnologyXuzhou 221116China Key Laboratory of Deep Coal Resource Mining of Ministry of Education China University of Mining&TechnologyXuzhou 221116China College of Mining Engineering and Geology Xinjiang Institute of EngineeringUrumqi 830000China CT Room Xuzhou Central HospitalXuzhou 221009China

Broken gangue has been extensively used in rockfill dams,subgrade,embankment,foundation cushion and other engineering construction.The deformation characteristics of broken gangue under the bearing compression play a decisive role in the firmness,stability and safety of these structures(buildings),and the meso-fabric change of broken gangue under the bearing compression significantly affects its macro deformation.In this study,the transparent characterization and quantitative analysis of 3D fabric of broken gangue under the bearing compression were performed through CT scanning test,image processing and 3D reconstruction technology,and the influence mechanism of internal fabric of broken gangue on its macro deformation was revealed.The results show that:In the loading stage of 0–2 MPa,the sharp corners,thin edges on the blocks and the bar-shaped and blade-shaped blocks with poor regularity are broken first under the bearing compression;in the loading stage of 2–8 MPa,a large number of larger particles in the sample are crushed in the mode of fragmentation;in the loading stage of 8–10 MPa,the breakage degree of samples is relieved.The axial displacement of the block inside the sample occurs,as well as the lateral displacement of the block converging to the central axis of the sample.In the rapid deformation stage,the macro deformation of the broken gangue is mainly caused by the rearrangement and adjustment of the block structure and the breakage of the block;in the slow deformation stage,it is mainly caused by the breakage of the block;in the stable deformation stage,it is mainly caused by the optimization and adjustment of the bearing skeleton in the sample.

关键词： Bearing compression Broken gangue 3D fabric Transparent characterization Quantitative analysis

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“第二个结合”与中国式现代化的文化形态

马克思主义与现实 2024年第1期 1-10,204页

作者：黄一兵中央党史和文献研究院

“把马克思主义基本原理同中国具体实际相结合、同中华优秀传统文化相结合”的重要论断,是我们党对马克思主义中国化时代化历史经验的深刻总结,是对中华文明发展规律的深刻把握。马克思主义是具有实践形态的革命理论,也是继承人类优秀... 详细信息

“把马克思主义基本原理同中国具体实际相结合、同中华优秀传统文化相结合”的重要论断,是我们党对马克思主义中国化时代化历史经验的深刻总结,是对中华文明发展规律的深刻把握。马克思主义是具有实践形态的革命理论,也是继承人类优秀传统文化、具有先进文化形态的科学理论。中华优秀传统文化是中华民族的文化基因和独特精神标识,为德润人心提供丰富滋养,为治国理政提供有益启示,以其永恒的时代内涵充实了马克思主义的文化生命。中华优秀传统文化同科学社会主义价值观主张具有高度契合性,价值观念融通不断赋予马克思主义科学理论以鲜明的中国特色,不断夯实马克思主义中国化时代化的历史基础和群众基础,推动了中华文明的生命更新和现代转型。“结合”是马克思主义基本原理同中华优秀传统文化相结合的核心和实质,要坚持马克思主义的主导地位,运用马克思主义激活中华民族创造的伟大文明,以鲜明的民族风格和广阔的国际视野,推动中华优秀传统文化创造性转化、创新性发展,不断培育和创造新时代中国特色社会主义文化。

关键词：马克思主义中国化时代化 “第二个结合” 中华优秀传统文化中国式现代化的文化形态

第三个历史决议与中共党史研究的几个重大问题

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中共党史研究 2022年第1期 8-15页

作者：黄一兵中共中央党史和文献研究院

党的十九届六中全会审议通过的《中共中央关于党的百年奋斗重大成就和历史经验的决议》(也称“第三个历史决议”),系统回顾了一百年来党走过的光辉历程、开辟的伟大道路,系统梳理了党在各个历史时期实现的奋斗目标、办成的历史大事,系... 详细信息

党的十九届六中全会审议通过的《中共中央关于党的百年奋斗重大成就和历史经验的决议》(也称“第三个历史决议”),系统回顾了一百年来党走过的光辉历程、开辟的伟大道路,系统梳理了党在各个历史时期实现的奋斗目标、办成的历史大事,系统总结了党顽强奋斗的历史意义和取得的历史经验,深刻揭示了中国共产党为什么能、马克思主义为什么行、中国特色社会主义为什么好的历史逻辑,深刻回答了中国共产党是什么、要干什么的历史之问。

关键词：中共党史研究决议系统梳理光辉历程中国特色社会主义六中全会重大成就奋斗目标

Improving the room-temperature bendability of Mg-3Al-1Zn alloy sheet by introducing a bimodal microstructure and the texture re-orientation

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International Journal of Minerals,Metallurgy and Materials 2022年第7期29卷 1322-1333页

作者： Chao He yibing Zhang Ming Yuan Bin Jiang Qinghang Wang Yanfu Chai Guangsheng huang Dingfei Zhang Fusheng Pan State Key Laboratory of Mechanical Transmissions College of Materials Science and EngineeringChongqing UniversityChongqing 400044China School of Chemistry and Materials Science Hubei Engineering UniversityXiaogan 432000China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China School of Mechanical Engineering Yangzhou UniversityYangzhou 225127China School of Mechanical and Electrical Engineering Shaoxing UniversityShaoxing 312000China

A significant enhancement of bendability was achieved by the introduction of bimodal microstructure for AZ31B alloy sheets via pre-compression and subsequent annealing(PCA)process.This combined treatment led to the c-axis of the extracted samples that were inclined by 30°to the rolling direction(30°sample)further shifting toward the rolling direction(RD)and resulting in a higher Schmid factor(SF)value of basal slip under the RD tensile stress.Furthermore,the bimodal microstructure that was introduced by the PCA process broke the damage bands(DBs)in the initial hot rolled AZ31B alloy sheets and gave rise to a more uniform strain distribution in the outer tension region of the bending samples,in which the tensile deformation was accommodated by the equally distributed{101^(-)2}tension twinning and basal slip.Consequently,the bimodal microstructure,shifted basal texture and the modification of DBs were responsible for the significant enhancement in the bendability of the AZ31 alloys.

关键词： magnesium alloy pre-compression texture bimodal microstructure bendability

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中国共产党与中国式现代化的四次历史性跨越

党的文献 2022年第6期 25-36页

作者：黄一兵中共中央党史和文献研究院北京100017

中国式现代化,是中国共产党领导的社会主义现代化。自诞生以来,中国共产党团结带领人民不懈奋斗,推动中国式现代化实现四次历史性跨越,有力推进了中华民族伟大复兴进程。这就是:新民主主义革命时期,向着中国式现代化探索正确方向的跨越... 详细信息

中国式现代化,是中国共产党领导的社会主义现代化。自诞生以来,中国共产党团结带领人民不懈奋斗,推动中国式现代化实现四次历史性跨越,有力推进了中华民族伟大复兴进程。这就是:新民主主义革命时期,向着中国式现代化探索正确方向的跨越;社会主义革命和建设时期,向着为实现“四个现代化”而奋斗的跨越;改革开放和社会主义现代化建设新时期,向着“中国式的四个现代化”的跨越;中国特色社会主义新时代,向着全面建设社会主义现代化的跨越。中国式现代化的开创、推进和拓展,不仅对中华民族和中国社会的发展具有深远历史意义,而且对世界社会主义和人类文明的发展具有重大现实意义。

关键词：中国共产党中国式现代化中华民族伟大复兴

Can phosphate compounds be used to reduce the plant uptake of Pb and resist the Pb stress in Pb-contaminated soils?

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Journal of Environmental Sciences 2009年第3期21卷 360-365页

作者： CHEN Shibao CHEN Li MA yibing huang Yizong Ministry of Agriculture Key Laboratory of Plant Nutrition and Nutrient Cycling and Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China Institute of Plant Protection and Environmental Protection Beijing Academy of Agricultural and Forestry Science Beijing 100097 China Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The effects of different phosphate-amendments on lead （Pb） uptake, the activities of superoxide dismutase （SOD） and the level of malondialdehyde （MDA） in cauliflower （Brassica oleracea L.） in contaminated soils with 2500, or 5000 mg P2O5/kg soil of hydroxyapatite （HA）, phosphate rock （PR）, single-superphosphate （SSP） and the mix of HA/SSP （HASSP） were evaluated in pot experiments. Results showed that the Pb concentrations in shoots and roots decreased by 18.3%-51.6% and 16.8%-57.3% among the treatments respectively compared to the control samples. The efficiency order of these phosphate-amendments in reducing Pb uptake was as follows： HASSP= HA 〉 SSP ,= PR. With the addition of SSP, HA and the mix of HA/SSP, the SOD activity in shoot was reduced markedly （P 〈 0.05） compared with that in the control group. For example, the SOD activities in shoot by the treatments of HASSP, SSP, and HA in 5000 mg P2O5/kg were found to be only 51.3%, 56.2%, and 56.7%, respectively. Similar effects were also observed on the level of MDA in the shoots with a decrease in 24.5%-56.3%. The results verified the inference that phosphate compounds could be used to reduce the plant uptake of Pb and resist the Pb stress in the plant vegetated in Pb-contaminated soils.

关键词： phosphate amendments lead superoxide dismutase （SOD） malondialdehyde （MDA） contaminated soil