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Microcrack analysis of Sanya grantite fragments from rockburst tests

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Mining Science and Technology 2010年第2期20卷 238-243页

作者： HE, Manchao NIE, Wen han, liqiang LING, Lijing state key laboratory of geomechanics and deep underground engineering beijing 100083china school of mechanics & civil engineering china university of mining & technologybeijing 100083china school of mechanics & civil engineering china university of mining & technologybeijing 100083china

Fractures running along a plane reflect the cracking *** this paper uniaxial and rockburst tests on a group of granite specimens from Sanya province are *** electron microscopic imaging was used to characterize the *** fracture mechanics were used to analyze the microcracks in terms of both the crack type and the mineral constituent.A statistical analysis showed that the area of inter-granular cracking exceeds that of intra-granular *** types of crack were observed in the cracked *** percentage of intra-granular cracks in fragments from rockburst tests exceeds that from uniaxial compression *** results also showed that feldspar deformation was the main cause of fracture and that the consolidation along quartz grain boundaries was another weak area in the *** along quartz grains had enough energy to enter the quartz crystal in the rockburst *** these results contribute to further research on rockburst mechanics.

关键词： granite rockburst medium fragment quartz feldspar fractal analysis

Knockout of butyrophilin subfamily 1 member A1(BTN1A1) alters lipid droplet formation and phospholipid composition in bovine mammary epithelial cells

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Journal of Animal Science and Biotechnology 2020年第4期11卷 975-985页

作者： liqiang han Menglu Zhang Zhiyang Xing Danielle N.Coleman Yusheng Liang Juan J.Loor Guoyu Yang College of Animal Science and Veterinary Medicine Henan Agricultural UniversityZhengzhou 450002PR China Department of Animal Sciences and Division of Nutritional Sciences University of IllinoisUrbanaIllinois 61801USA.

Background: Milk lipids originate from cytoplasmic lipid droplets(LD) that are synthesized and secreted from mammary epithelial cells by a unique membrane-envelopment process. Butyrophilin 1 A1(BTN1 A1) is one of the membrane proteins that surrounds LD, but its role in bovine mammary lipid droplet synthesis and secretion is not well ***: The objective was to knockout BTN1 A1 in bovine mammary epithelial cells(BMEC) via the CRISPR/Cas9 system and evaluate LD formation, abundance of lipogenic enzymes, and content of cell membrane phospholipid(PL) species. Average LD diameter was determined via Oil Red O staining, and profiling of cell membrane phospholipid species via liquid chromatography-tandem mass spectrometry(LC-MS/MS).Results: Lentivirus-mediated infection of the Cas9/sg RNA expression vector into BMEC resulted in production of a homozygous clone BTN1 A1^((-/-)). The LD size and content decreased following BTN1 A1 gene knockout. The m RNA abundance of fatty acid synthase(FASN) and peroxisome proliferator-activated receptor-gamma(PPARG) was downregulated in the BTN1 A1^((-/-))clone. Subcellular analyses indicated that BTN1 A1 and LD were co-localized in the cytoplasm. BTN1 A1 gene knockout increased the percentage of phosphatidylethanolamine(PE) and decreased phosphatidylcholine(PC), which resulted in a lower PC/PE ***: Results suggest that BTN1 A1 plays an important role in regulating LD synthesis via a mechanism involving membrane phospholipid composition.

关键词： Lipid droplet Mammary epithelial cell Milk fat globule Phospholipid

Analysis of microscopic pore structures of rocks before and after water absorption

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Mining Science and Technology 2011年第2期21卷 287-293页

作者： Li Dejian Wang Guilian han liqiang Liu Peiyu He Manchao Yang Guoxing Tai Qimin Chen Cheng State Key Laboratory of Geomechanics and Deep Underground Engineering Beijing 100083 China Institute of Geotechnical Engineering China University of Mining ＆ Technology Beijing 100083 China Sichuan Staff University of Science and Technology Sichuan 610101 China Engineering Research Institute of General Armament Department Beijing 100083 China

Hydrophilic characteristics of rocks are affected by their microscopic pore structures,which clearly change after water *** absorption tests and scanning electron microscopic（SEM） experiments on rock samples,located at a site in Tibet,China,were carried out Changes of rock pore structures before and after water absorption were studied with the distribution of pore sizes and fractal characteristics of *** results show that surface porosities,fractal dimensions of pores and the complexity of pore structures increased because the number of new small pores produced increased or the original macropore flow channels were expanded after rocks absorbed *** were points of inflection on their water absorption *** water absorption of other rocks,surface porosities and fractal dimensions of pores and complexity of pore structures decreased as the original pore flow channels became *** absorption curves did not *** porosity and the pore fractal dimensions of rocks have good linear relationships before and after water absorption.

关键词： Hydrophilic characteristics Pore structures Pore size distribution Pore fractal characteristics

Artificial intelligence optimization and controllable slow-release iron sulfide realizes efficient separation of copper and arsenic in strongly acidic wastewater

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Journal of Environmental Sciences 2024年第5期139卷 293-307页

作者： Xingfei Zhang Chenglong Lu Jia Tian liqiang Zeng Yufeng Wang Wei Sun Haisheng han Jianhua Kang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Centre for Mined Land Rehabilitation Sustainable Minerals InstituteThe University of QueenslandBrisbane 4072Australia

Iron sulfide(FeS)is a promising material for separating copper and arsenic from strongly acidic wastewater due to its S^(2-)slow-release ***,uncertainties arise because of the constant changes in wastewater composition,affecting the selection of operating parameters and FeS *** this study,the aging method was first used to prepare various controllable FeS nanoparticles to weaken the arsenic removal ability without affecting the copper *** experiments were conducted,and the results identified the Cu/As ratio,H_(2)SO_(4) concentration,and FeS dosage as the three main factors influencing the separation *** backpropagation artificial neural network(BP-ANN)model was established to determine the relationship between the influencing factors and the separation *** correlation coefficient(R)of overall model was 0.9923 after optimizing using genetic algorithm(GA).The BP-GA model was also solved using GA under specific constraints,predicting the best solution for the separation process in *** predicted results show that the high temperature and long aging time of FeS were necessary to gain high separation efficiency,and the maximum separation factor can reached 1,*** study provides a suitable sulfurizing material and a set of methods and models with robust flexibility that can successfully predict the separation efficiency of copper and arsenic from highly acidic environments.

关键词： FeS nanoparticles Aging Sulfide precipitation Orthogonal experiment Artificial neural network Prediction

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脂噬对奶牛乳腺上皮细胞脂滴大小的调控研究

畜牧兽医学报 2024年第3期55卷 1095-1101页

作者：康方圆刘镇滔吴奎显倪晗钟凯李和平杨国宇韩立强河南农业大学动物医学院、农业部动物生化与营养重点实验室郑州450046 河南牧业经济学院、河南省动物生长发育重点实验室郑州450046

脂噬是一种新的自噬形式,可以选择性识别脂滴并将其降解,在维持细胞内脂质稳态等过程中发挥着重要的作用。本研究旨在探讨奶牛乳腺上皮细胞经饥饿诱导脂噬后对细胞脂滴大小的调控作用。试验用100μmol·L^(-1)的亚油酸处理细胞24 h,刺... 详细信息

脂噬是一种新的自噬形式,可以选择性识别脂滴并将其降解,在维持细胞内脂质稳态等过程中发挥着重要的作用。本研究旨在探讨奶牛乳腺上皮细胞经饥饿诱导脂噬后对细胞脂滴大小的调控作用。试验用100μmol·L^(-1)的亚油酸处理细胞24 h,刺激细胞脂滴蓄积,然后分别饥饿诱导细胞0、6、12、24、48 h,油红O染色观察细胞内脂滴的尺寸和数量随饥饿时间的变化情况,随后饥饿诱导24 h通过免疫荧光观察脂滴和自噬蛋白LC3的共定位,蛋白免疫印迹检测细胞内自噬蛋白LC3和P62的表达,透射电镜观察脂滴自噬情况。结果发现:随着饥饿处理时间的延长,脂滴直径从1.57μm显著增加到2.12μm,每个细胞的脂滴数量显著减少,从39个·cell^(-1)减少到24个·cell^(-1),大脂滴比例显著增加,小脂滴比例显著减少(P<0.05),免疫荧光发现LC3与脂滴发生共定位,透射电镜观察发现自噬溶酶体包裹着脂滴,饥饿处理24 h后LC3Ⅱ/LC3Ⅰ蛋白的比值显著增加1倍,P62蛋白表达显著下降(P<0.05)。以上结果表明,脂噬对奶牛乳腺上皮细胞脂滴的大小发挥调控作用。

关键词：奶牛乳腺上皮细胞脂滴脂噬

A new insight into LPSO phase transformation and mechanical properties uniformity of large-scale Mg-Gd-Y-Zn-Zr alloy prepared by multi-pass friction stir processing

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Journal of Magnesium and Alloys 2024年第5期12卷 2041-2056页

作者： Xiaohu Guan Wen Wang Ting Zhang Pai Peng Qiang Liu Peng han Ke Qiao Jun Cai liqiang Wang Kuaishe Wang School of Metallurgical Engineering National and Local Joint Engineering Research Center for Functional Materials ProcessingXi’an University of Architecture and TechnologyNo.13 Yanta RoadXi’anShaanxi 710055China Xi’an Rare Metal Materials Institute Co.Ltd Xi’an 710016China State Key Laboratory of Metal Matrix Composites School of Material Science and EngineeringShanghai Jiao Tong UniversityNo.800 Dongchuan RoadShanghai 200240China

A large-scale fine-grained Mg-Gd-Y-Zn-Zr alloy plate with high strength and ductility was successfully prepared by multi-pass friction stir processing(MFSP)technology in this *** structure of grains and long period stacking ordered(LPSO)phase were characterized,and the mechanical properties uniformity was ***,a quantitative relationship between the microstructure and tensile yield strength was *** results showed that the grains in the processed zone(PZ)and interfacial zone(IZ)were refined from 50μm to 3μm and 4μm,respectively,and numerous original LPSO phases were *** IZ,some block-shaped 18R LPSO phases were transformed into needle-like 14H LPSO phases due to stacking faults and the short-range diffusion of solute *** severe shear deformation in the form of kinetic energy caused profuse stacking fault to be generated and move rapidly,greatly increasing the transformation rate of LPSO *** MFSP,the ultimate tensile strength,yield strength and elongation to failure of the large-scale plate were 367 MPa,305 MPa and 18.0% *** refinement and LPSO phase strengthening were the major strengthening mechanisms for the MFSP *** particularly,the strength of IZ was comparable to that of PZ because the strength contribution of the 14H LPSO phase offsets the lack of grain refinement strengthening in *** result opposes the widely accepted notion that IZ is a weak region in MFSP-prepared large-scale fine-grained plate.

关键词： Friction stir processing Multi-pass Mg-Gd-Y-Zn-Zr alloy LPSO phase transformation Mechanical properties

Catalytic effects of V-and O-species derived from PrF_(3)/V_(2)C for efficient hydrogen storage in MgH_(2)

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Nano Research 2024年第8期17卷 7117-7125页

作者： Zhenluo Yuan Yuhang Wang Xiuxiu Zhang Shuyan Guan Xiaojiao Wang liqiang Ji Qiuming Peng Shumin han Yanping Fan Baozhong Liu College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo 454000China Henan Famous Diamond Co. Ltd.Mengzhou 454763China School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

Magnesium hydride(MgH_(2))is considered as an ideal hydrogen storage material with excellent hydrogen capacity,but the slow kinetics impedes its ***,an efficient additive of V2C MXene-anchored PrF_(3) nanoparticles(PrF_(3)/V_(2)C)was synthesized,which presents excellent catalytic effect in improving the reversibility and stability of hydrogen storage in MgH_(2).The initial dehydrogenation temperature of the 5 wt.% PrF_(3)/V_(2)C-containing MgH_(2)(182℃) is 105℃ lower than that of pure MgH_(2),and 6.5 wt.%hydrogen is rapidly released from 5 wt.%PrF_(3)/V_(2)C-added MgH_(2)sample in 6 min at 240℃.In addition,5 wt.%PrF_(3)/V_(2)C-containing MgH_(2) sample possesses outstanding reversible hydrogen storage capability of 6.5 wt.% after 10 cycles of dehydrogenation and *** analysis shows that the introduction of Pr improves the stability of V-species(V^(0)and V^(2+))and O-species(lattice oxygen(OL)and vacancy oxygen(OV))formed during ball milling,promotes the interaction between V-species and O-species,and enhances their reversibility,which contributes to the significant improvement in re/dehydrogenation reversibility and cycling stability of MgH_(2).This study provides effective ideas and strategies for the purpose of designing and fabricating high-efficient catalysts for solid-state hydrogen storage materials.

关键词： hydrogen storage materials MgH_(2) dehydrogenation reversibility cyclic stability

一种混合认知RF和MIMO FSO系统的中断概率分析

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中国激光 2018年第4期45卷 233-240页

作者：韩立强江红兵燕山大学电气工程学院河北秦皇岛066004

给出了一种串联衬底认知射频(RF)网络与多输入多输出(MIMO)自由空间光通信(FSO)链路的双跳传输系统,分析了其中断概率。对于射频链路,采用瑞利衰落分布模型,分析次级用户与主用户共享频谱的衬底认知无线电网络;对于MIMO FSO链路,采用Gam... 详细信息

给出了一种串联衬底认知射频(RF)网络与多输入多输出(MIMO)自由空间光通信(FSO)链路的双跳传输系统,分析了其中断概率。对于射频链路,采用瑞利衰落分布模型,分析次级用户与主用户共享频谱的衬底认知无线电网络;对于MIMO FSO链路,采用Gamma-Gamma大气湍流模型,考虑大气衰减效应和大气湍流效应,通过等增益合并建立MIMO FSO的信道模型。推导出中断概率的闭合表达式,仿真分析各种天气条件和大气湍流对串级链路的影响,结果显示随着次级用户发射器的峰值发射功率增大和发射孔径与接收孔径的数目增多,大气效应的影响逐渐减小,通信性能随之提高。

关键词：光通信自由空间光通信双跳中继系统中断概率衬底认知无线电

大气衰减和大气湍流效应下多输入多输出自由空间光通信的性能

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中国激光 2016年第7期43卷 223-230页

作者：韩立强游雅晖燕山大学电气工程学院河北秦皇岛066004

为了减小大气衰减效应和大气湍流效应对自由空间光通信的影响,采用了多输入多输出技术。假定自由空间光通信系统采用开关键控强度调制直接探测,信道独立同分布、无记忆平稳遍历并且具有加性高斯白噪声,在发射端和接收端都可以获取理想... 详细信息

为了减小大气衰减效应和大气湍流效应对自由空间光通信的影响,采用了多输入多输出技术。假定自由空间光通信系统采用开关键控强度调制直接探测,信道独立同分布、无记忆平稳遍历并且具有加性高斯白噪声,在发射端和接收端都可以获取理想信道状态信息;建立了综合大气效应下多输入多输出信道模型和系统模型,推导了等增益分集合并下自由空间光通信系统的遍历容量和中断概率闭合表达式,仿真分析了各种天气条件和大气湍流对空间光通信链路的影响,结果显示随着发射孔径和接收孔径的数目增多,大气效应的影响逐渐减小,通信系统性能随之提高。从系统复杂度及性能提高程度综合考虑,选择2个发射孔径、2个接收孔径较为合适。

关键词：光通信多输入多输出自由空间光通信遍历容量中断概率伽马-伽马分布