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Chinese Physics B 2021年第10期30卷 665-672页

作者： Jun-bao Ma Wei-Bu Wang ji-Guo Su Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China

The realization of protein functional movement is usually accompanied by specific conformational changes,and there exist some key residues that mediate and control the functional motions of proteins in the allosteric *** the present work,the perturbation-response scanning method developed by our group was combined with the molecular dynamics(MD)simulation to identify the key residues controlling the functional movement of *** our method,a physical quantity that is directly related to protein specific function was introduced,and then based on the MD simulation trajectories,the perturbation-response scanning method was used to identify the key residues for functional motions,in which the residues that highly correlated with the fluctuation of the function-related quantity were identified as the key residues controlling the specific functional motions of the *** protein systems,i.e.,the heat shock protein 70 and glutamine binding protein,were selected as case studies to validate the effectiveness of our *** calculated results are in good agreement with the experimental *** location of the key residues in the two proteins are similar,indicating the similar mechanisms behind the performance of their biological functions.

关键词： protein functional movements molecular dynamics simulations perturbation-response scanning method

I-DCGAN and TOPSIS-IFP:A simulation generation model for radiographic flaw detection images in light alloy castings and an algorithm for quality evaluation of generated images

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China Foundry 2024年第3期21卷 239-247页

作者： Ming-jun Hou Hao Dong Xiao-yuan ji Wen-bing Zou Xiang-sheng Xia meng Li Ya-jun Yin bao-hui Li Qiang Chen jian-xin Zhou State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China Xinjiang Technology(jiangsu)Co. Ltd.Nantong 226100JiangsuChina Southwest Technique and Engineering Research Institute Chongqing 400039China Shanghai Spaceflight Precision Machinery Institute Shanghai 201600China

The intelligent detection technology driven by X-ray images and deep learning represents the forefront of advanced techniques and development trends in flaw detection and automated evaluation of light alloy ***,the efficacy of deep learning models hinges upon a substantial abundance of flaw *** existing research on X-ray image augmentation for flaw detection suffers from shortcomings such as poor diversity of flaw samples and low reliability of quality *** this end,a novel approach was put forward,which involves the creation of the Interpolation-Deep Convolutional Generative Adversarial Network(I-DCGAN)for flaw detection image generation and a comprehensive evaluation algorithm named TOPSIS-IFP.I-DCGAN enables the generation of high-resolution,diverse simulated images with multiple appearances,achieving an improvement in sample diversity and quality while maintaining a relatively lower computational ***-IFP facilitates multi-dimensional quality evaluation,including aspects such as diversity,authenticity,image distribution difference,and image distortion *** results indicate that the X-ray radiographic images of magnesium and aluminum alloy castings achieve optimal performance when trained up to the 800th and 600th epochs,*** TOPSIS-IFP value reaches 78.7%and 73.8%similarity to the ideal solution,*** to single index evaluation,the TOPSIS-IFP algorithm achieves higher-quality simulated images at the optimal training *** approach successfully mitigates the issue of unreliable quality associated with single index *** image generation and comprehensive quality evaluation method developed in this paper provides a novel approach for image augmentation in flaw recognition,holding significant importance for enhancing the robustness of subsequent flaw recognition networks.

关键词： light alloy casting flaw detection image generator discriminator comprehensive evaluation index

ZERNIKE ASTIGMATISM AND VISUAL PERFORMANCE IN MYOPIC EYES BY RIGID GAS PERMEABLE CONTACT LENSES WEAR

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Journal of Innovative Optical Health Sciences 2012年第3期5卷 8-14页

作者： jiNHUA bao XINjiE MAO HAIRONG WANG ji CHE FAN LU School of Optometry and Ophthalmology Wenzhou Medical CollegeWenzhouZhejiangP.R.China New England College of Optometry BostonMassachusettsUSA

To investigate the effects of rigid-gas-permeable contact lens(RGP-CL)wear on Zernike astigmatism and visual performance in myopic ***:A wavefront sensor was used to evaluate Zernike astigmatism for 21 eyes with minimum astigmatism and 18 eyes with moderate astigmatism under three different modes of refractive correction:the RGP-CL,spectacle lens correcting spherical equivalent(SL)and spectacle lens fully correcting spherical error and astigmatism(fSL).Contrast visual acuity was assessed with a VA tester at four contrast levels and two luminance ***:Compared to the SL wear,RGP-CL wear changed the main axis astigmatism(Z_(2)^(2))from0:09-0:34 to 0.34-0.22 for the minimum astigmatism group,while the contrast VA was improved about 0.05 LogMAR(F=8:06,p<0:01).For the group with moderate astigmatism,significant reduction in Z_(2)^(2)was found for both fSL wear(t=4:78,p<0:001)and RGP-CL wear(t=6:29,p<0:0001).The changes in astigmatism were significantly correlated between the fSL and RGP-CL wears(r=0:897,p<0:0001 for Z_(2)^(-2);and r=0:643,p=0:004 for Z_(2)^(2)).Contrast VA was significantly improved for both fSL and RGP-CL wears and the improvements were significantly correlated between each other for all four contrast levels and two ***:RGP-CL wear induces astigmatism for the eyes with minor astigmatism probably due to a correction of corneal astigmatism and thus a manifesting of the lens *** the astigmatic eyes,RGP-CL wear has similar effect on correcting astigmatism as the spectacle lens wear with spherical-cylinder correction and also produces similar visual improvement.

关键词： Wavefront aberration Zernike aberration contrast visual acuity rigid-gas-permeable contact lens spectacle lens

Experimental studies on rock failure mechanisms under impact load by single polycrystalline diamond compact cutter

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Petroleum Science 2023年第5期20卷 3100-3109页

作者： Zhao-Sheng ji jin-bao jiang Huai-Zhong Shi Bang-Min Li Drilling Engineering Technology Research Institute Sinopec Zhongyuan Petroleum Engineering CompanyPuyangHenan457001China State Key Laboratory of Petroleum Resources and Prospecting Beijing102249China

Percussive drilling shows excellent potential for promoting the rate of penetration(ROP)in drilling hard *** diamond compact(PDC)bits account for most of the footage drilled in the oil and gas *** reveal the rock failure mechanisms under the impact load by PDC bits,a series of drop tests with a single PDC cutter were conducted to four kinds of rocks at different back rake angles,drop heights,drop mass,and drop *** the morphology characteristics of the craters were obtained and quantified by using a three-dimensional *** fracture micrographs can be observed by using scanning electron microscope(SEM).The distribution and propagation process of subsurface cracks were captured in rock-like silica glass by a high-speed photography *** results can indicate that percussive drilling has a higher efficiency and ROP when the rock fractures in brittle *** failure mode of rock is related with the type of rock,the impact speed,and the back rake angle of the *** the penetration depth and fragmentation volume get the maximum values at a back rake angle of about 45°.Increasing the weight and speed of falling hammer is beneficial to improving the rock breaking effects and *** subsurface cracks under the impact load by a single PDC cutter is shaped like a clamshell,and its size is much larger than the crater *** findings can help to shed light on the rock failure mechanisms under the impact of load by a single PDC cutter and provide a theoretical explanation for better field application of percussive drilling.

关键词： Percussive drilling PDC cutter Drop test Failure mechanism Subsurface cracks

Anthropogenic,detritic and atmospheric soil-derived sources of lead in an alpine poor fen in northeast China

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Journal of Mountain Science 2016年第2期13卷 255-264页

作者： bao Kun-shan SHEN ji WANG Guo-ping TSERENPIL Shurkhuu State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of Sciences Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of Sciences Nuclear Research Center National University of Mongolia Nuclear Application and Research Center Akdeniz University

Ombrotrophic bogs are faithful archive of atmospheric metal deposition, but the potential for fens to reconstruct environmental change is often underestimated. In this study, some new data on the Pb depositional history in northeast China were provided using two ^210Pb-dated peat sequences from a poor fen in the Fenghuang Mountain of Heilongjiang province. Anthropogenic, detritic and atmospheric soil sources were discriminated using a two-step sequential digestion （weak acid leaching to liberate mobile Pb which is often regarded as anthropogenic Pb, especially for recent samples） and a ratio of unsupported ^210Pb and supported ^210Pb with the logic of that the ^214Pb mainly represents the residual detritus （constant throughout the core） and the unsupported ^210Pb arises from atmospheric fallout. A higher ^210Pb/^214Pb suggests more contributions from atmospheric deposition to the Pb content in the peat, and a ratio of 10 was defined to indicate the boundary between detrific input and atmospheric deposition. The detritic Pb was estimated to be 10-13 mg·kg^-1, the anthropogenic Pb ranged from 10-80 mg·kg^-1, and the atmospheric soil-derived Pb ranged from 〈 5 mg·kg^-1 to 30 mg·kg^-1. The history of anthropogenic Pb pollution over the last 150 years was reconstructed, and the calculated Pb deposition rate （AR Pb） ranged from 5 to 56 mg·m^-2·yr^-1. Using Ti as a reliable reference, the enrichment factor of Pb （EF Pb） relative to the upper continental crust was calculated. Both AR Pb and EF Pb increased with time, especially after the foundation of the People＇s Republic of China. This is consistent with increasing industrialization and coal burning in the last 60 years in northeast China. The present record of anthropogenic Pb deposition was consistent with the previous reports and an increasing trend of environmental pollution due to anthropogenic activities, in contrasts to Europe and North America which have experienced a major environmental cleanup. For the first tim

关键词： Ombrotrophic bog Minerotrophicpeatland Pb deposition rate Enrichment factor ^210Pb and ^137Cs Metal pollution

Paleosandstorm characteristics and lake evolution history deduced from investigation on lacustrine sediments——The case of Hongjiannao Lake, Shaanxi Province

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Chinese Science Bulletin 2005年第20期50卷 2355-2361页

作者： SHEN ji WANG Yong YANG Xiangdong ZHANG Enlou YANG bao ji Junfeng Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Graduate School Chinese Academy of Sciences Beijing 100039 China Key Laboratory of Ice and Cold Region Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Institute of Surfacial Geochemistry State Laboratory of Mineral Deposits Research Department of Earth Sciences. Nanjing University Nanjing 210009 China

Sediment cores from desert lakes serve as good records of the frequency and intensity of sandstorms in his- tory. By multi-proxy analysis of grain-size, magnetic suscep- tibility, TOC and Rb/Sr ratio, the paleosandstorm character- istics and lake evolution history in Yulin Area for the past 80 years. are discussed in this article. It is revealed that Hong- jiannao Lake formed in about 1928 A.D. and in its initial stage sandstorms were prevalent with three extremes taking place in 1936 A.D., 1939 A.D. and 1941 A.D.. During the ex- pansion period of 1952―1960 A.D., inflow waters to the lake increased sharply and a lot more weathered materials were carried into the lake. The frequency and intensity of sand- storms have reduced a lot since 1960s and the “double peaks” feature of the grain-size frequency curve has changed into the “single peak” feature. Study on the catchment ecol- ogy of the lake shows that the occurrence of sandstorms has been effectively restrained by the forest plantation and water and soil conservation.

关键词：陕西省湖泊沉积物沙暴磁化系数进化历史

Effect of MgO promoter on Ni-based SBA-15 catalysts for combined steam and carbon dioxide reforming of methane

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Journal of Natural Gas Chemistry 2008年第3期17卷 225-231页

作者： Bingyao Huang Xiujin Li Shengfu ji bao Lang Fabien Habimana Chengyue Li State Key Laboratoly of Chemical Resource Engineering Beijing University of Chemical Technology. Beijing 100029. China Department of Environmental Engineering Beijing University of Chemical Technology Beijing 100029 China

A series of Ni/SBA-15 catalysts with Ni contents ranging from 5 wt% to 15 wt%, as well as another series of 10%Ni/MgO/SBA-15 catalysts, in which the range of the MgO content was from 1 wt% to 7 wt%, were prepared, and their catalytic performances for the reaction of combined steam and carbon dioxide reforming of methane were investigated in a continuous flow microreactor. The structures of the catalysts were characterized using the XRD, H2-TPR and CO2-TPD techniques. The results indicated that the CO selectivity for this reaction was very close to 100%, and the H2/CO ratio of the product gas could be controlled by changing the H2O/CO2 molar ratio of the feed gas. The simultaneous and plentiful existing of steam and CO2 had a significant influence on the catalytic performance of the 10%Ni/SBA-15 catalyst without modification. After reacting at 850 °C for 120 h over this catalyst, the CH4 conversion dropped from 98% to 85%, and the CO2 conversion decreased from 86% to 53%. However, the 10%Ni/3%MgO/SBA-15 catalyst exhibited a much better catalytic performance, and after reacting for 620 h, the CO2 conversion over this catalyst dropped from 92% to around 77%, while the CH4 conversion was not decreased. Oxidation of the Ni0 species as well as carbon deposition during the reaction were the main reasons for the deactivation of the catalyst without modification. On the other hand, modification by the MgO promoter improved the dispersion of the Ni0 species, and enhanced the CO2 adsorption affinity which in turn depressed the occurring of carbon deposition, and thus retarded the deactivation process.

关键词： MgO promoter Ni-based catalyst SBA-15 methane combined steam carbon dioxide reforming synthesis gas

Optimization and mechanism of gold-bearing sulfide flotation

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Rare Metals 2014年第3期33卷 363-368页

作者： Zhong-Mei Sun Chun-bao Sun ji-Zhen Wang Wan-Zhong Yin School of Civil and Environmental Engineering University of Science and Technology Beijing Zijin Research Institute of Mining and Metallurgy School of Materials & Metallurgy Northeastern University College of Zi jin Mining Fuzhou University

In order to overcome the difficulty of extracting gold from gold-bearing sulfide ore by cyanide process flotation was adopted based on mineralogical analysis Mineralogy shows that gold particles are of superfine structure and mainly enclosed by sulfide ores. Primary gold-bearing sulfide ore is fine-grained pyrite and arsenopyrite. The paper describes the effects of ratios and dosage of activators and collectors on the recovery and grade of gold concentrate. A proper flotation flowsheet was then proposed based on experimental condition and closedcircuit test. The gold concentrate with the gold grade of25.14 g ton-1and the recovery of 86.94 % is obtained after one rougher, three cleaners, and four scavengers from fine grinding flotation process. Furthermore, the mechanisms of combined activators and combined collectors were studied by thermodynamic calculation, and structure-activity relationship of flotation reagent was also explained

关键词： Gold Pyrite Arsenopyrite Activator Combined reagent Flotation

Fe-Catalyzed Pictet-Spengler-Type Cyclization via Selective Four-Electron Reductive Functionalization of CO_(2)

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Chinese Journal of Chemistry 2021年第3期39卷 614-620页

作者： Wen-Duo Li jie Chen Dao Yong Zhu ji-bao Xia State Key Laboratory for Oxo Synthesis and Selective Oxidation Center for Excellence in Molecular SynthesisSuzhou Research Institute of LICPLanzhou Institute of Chemical Physics(LICP)Chinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Sciences Beijing 100049China

Main observation and conclusion Herein,we describe a novel catalytic Pictet-Spengler-type cyclization using CO_(2) as a nontoxic and sustainable C1 feedstock with envi-ronmentally benign and non-precious-metal iron as *** reaction is achieved by selective four-electron reduction of CO_(2) into methylene level intermediate through carefully tuning the reaction parameters.A variety of tetrahydro-B-carbolines and other nitro-gen-containing heterocycles can be easily obtained under mild *** studies have shown that tetrahy-dro-B-carbolines are probably obtained via spiroindolenine intermediates.

关键词： Carbon dioxide Iron catalysis Four-electron reduction Pictet-Spengler-type cyclization Tetrahydro-B-carboline

Radial Additive Friction Stir Repairing of Mechanical Hole Out of Dimension Tolerance of AZ31 Magnesium Alloy Assisted by Stationary Shoulder:Process and Mechanical Properties

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Acta Metallurgica Sinica(English Letters) 2021年第10期34卷 1345-1360页

作者： Ying-Ying Zuo Hua Liu Peng Gong Shu-De ji bao-Sheng Wu College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China

Radial additive friction stir repairing(R-AFSR)assisted by stationary shoulder was put forward in the present study,which can be employed to repair the mechanical hole out of dimension tolerance of AZ31 magnesium alloy *** results show that the stationary shoulder has sealed-barrier,heat-sink and extra-forging *** heat-sink effect improves the microstructure uniformity along the stir zone(SZ)thickness and the surface appearance of repaired hole,and the sealedbarrier and extra-forging effects eliminate the super-fine grain band in the ***,these three effects improve the formation quality of repaired region,thereby enhancing the mechanical properties of repaired mechanical hole compared with conventional *** tensile and compressive shear strengths of the repaired hole by stationary shoulder R-AFSR both increase first and then decrease when the rotating speed changes from 1200 to 1800 rpm,and these maximum values,respectively,reach 190±3 MPa and 64.5±2 MPa at 1400 *** addition of stationary shoulder during R-AFSR can obtain a higher-quality repaired hole and broaden the repairing process window.

关键词： Stationary shoulder Radial additive friction stir repairing Mechanical hole out of dimension tolerance AZ31 magnesium alloy Microstructure Mechanical properties