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The concept, structure and characteristics of the distributed virtual coal-mine geographical environment

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Journal of Coal Science & engineering(China) 2007年第4期13卷 547-552页

作者：刘冰刘延龙田茂义卢秀山石奉华 Ministerial Key Laboratory of mining Surveying Shandong University of Science and Technology Qingdao 266510 China Modern Education center Shandong University of Science and Technology Qingdao 266510 China Economy ＆ Information research Institute China Coal Research Institute Beijing 100013 China

Distributed virtual coal-mine geography environment（CM-DVGE） researches the virtual reality simulation of coal-mine environment in cyberspace and the performance of coal production process. The goal is to deal with the practical safety problems of observation, analysis, design and training during the underground coal production process. This paper first probed into the evolution of CM-DVGE from a historical point of view, then respectively analyzed the characteristics of its physical progressive levels according to the cognitivd law and its logical structure of data on the basis of data flow, and concluded by putting forward the prospect of the application of CM-DVGE, thus enriched and developed the method of synthetic study of coal mine.

关键词： distributed virtual coal mine geography environment(CM-DVGE) virtual reality geography environment coal mine

Effects of internal factors on surface wettability of corn stalk rind

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International Journal of Agricultural and Biological engineering 2015年第6期8卷 77-83页

作者： He Xun Wang Defu College of Mechanical and Electronic engineering Henan Agricultural UniversityZhengzhou 450002China Collaborative Innovation center of Henan province Biomass Energy Zhengzhou 450002China College of engineering Northeast Agricultural UniversityHarbin 150030China

Corn stalk is one of heterogeneous materials with anisotropy and *** the rind of corn stalk consists of rich lignin and cellulose similar to wood properties,and possessing high mechanical strength,then can be used as raw material of stalk artificial board and *** corn stalk rind has significant differences in fiber morphology,chemical composition and mechanical properties at different ***-SiO2 composite material contained in the epidermis of corn stalk rind is not conducive to exert adhesive into a *** study board-making technology by intact corn stalk rind,the wettability of corn stalk rind at different sampling heights is necessary to be analyzed by keeping or removing the *** analyze the surface wettability difference,the contact angle with water,element compositions and the chemical compositions of corn stalk rind at different sampling heights were studied before and after removal of epidermis.A Fourier transform infrared(FTIR)analysis was *** results showed that the removal of the epidermis could significantly improve the hydrophilicity of corn stalk *** removal of the epidermis,the varying contents of elements including C and Si dominate the surface wettability differences at different sampling heights of corn *** an increase in the sampling height,the mass fraction of C increases while that of Si decreases,which result in increasing *** removal of the epidermis,the surface wettability of corn stalk rind is mainly determined by the mass fraction of hemicellulose,and the higher the sampling height,the larger the mass fraction of hemicellulose resulting in the increase of hydrophilicity.

关键词： corn stalk rind wettability surface contact angle element analysis chemical compositions mechanism

Droplet Manipulation and Crystallization Regulation in Inkjet-Printed Perovskite Film Formation

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CCS Chemistry 2022年第5期4卷 1465-1485页

作者： Yajie Cheng Hangjuan Wu Junjie Ma Pengwei Li Zhenkun Gu Shuangquan Zang Liyuan Han Yiqiang Zhang Yanlin Song School of Materials Science and engineering Henan Institute of Advanced TechnologyZhengzhou UniversityZhengzhou 450001 College of Chemistry Zhengzhou UniversityZhengzhou 450001 State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240 Key Laboratory of green Printing Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing Engineering Research Center of Nanomaterials for Green Printing TechnologyNational Laboratory for Molecular Sciences(BNLMS)Beijing 100190

Emerging organic–inorganic metal halide perovskite materials have become the focus of the optoelectronics research community owing to their excellent photoelectric ***,challenges still exist for transferring the lab-made devices to largearea industrial *** printing(IJP)technology provides a promising way to fill the gap because of its precise droplet control and uniform large-scale deposition ***,an in-depth understanding of inkjet-printed perovskite films in terms of droplet manipulation and crystallization regulation is critical for upscaling the perovskite devices to commercial *** this review,we give an overview of inkjet-printed high-quality perovskite films and provide guidelines on inkjet-printing large-scale highperformance perovskite ***,we analyze theories of droplet formation and perovskite nucleation/crystallization dynamics and then focus on summarizing the perovskite film-formation strategies via IJP,in the aspects of ink engineering,the printing process,and ***,we review the recent advances of inkjet-printed perovskite films on optoelectronic devices,such as perovskite solar cells,perovskite light-emitting diodes,and perovskite ***,we highlight the“Trilogy Strategies,”including ink engineering,printing process,and posttreatment for printing high-quality perovskite films.

关键词： inkjet printing perovskite droplet manipulation crystallization film formation optoelectronic devices

Study of Organochlorine Pesticides in Eco-geochemical Survey of Soil in Shandong province

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Agricultural Biotechnology 2019年第2期8卷 196-200,204页

作者： Qing CAI Fang LIU Chunlan LI Shixin CAO Binbin LIU Jingjing WANG Shandong Institute of Geological Survey Land Quality Geochemistry and Pollution Prevention engineering technology research center of Shandong province Geological Environment Monitoring Master Station of Shandong province

Based on a comprehensive eco-geochemical survey of Shandong province, the differences in pesticide residue situation and contents of DDTs and HCHs in the soils of Yantai City and Southwest Shandong province(abbreviated as SSP) were studied in this paper. The results showed that the detection rates of DDTs and HCHs in the soil of SSP were apparently higher than Yantai City. However, the mean contents of DDTs and HCHs in the soil of Yantai were 9 and 25 times of SSP, respectively, and higher than the mean contents of many other cities and areas. p,p′-DDE was the main pesticide residual form in the soil of SSP. It is recognized as the degradation product of DDTs in oxidation environment in past, nevertheless, 5.52% of the soils in Yantai City still have a little of DDT input recently, which has posed a big impact on soil environment quality. β-HCH was the main form of the four isomers of HCHs in Yantai City, and α-HCH/γ-HCH in SSP was low. These reveal that the residual time of HCHs in the soils of both the two areas has a long period. After primary analysis, the risk of DDTs and HCHs in the soil of SSP is low, but DDTs in the soil of Yantai City still has a certain risk.

关键词： Soil Organochlorine pesticides Ecological risk Yantai City Southwest Shandong province

Unloading-slippage mechanism of coal bump in gateroad of longwall

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Geohazard Mechanics 2023年第3期1卷 208-217页

作者： Jun Han Dongxu Jia Qianjia Hui Luyu Cui Zhijie Zhu Chen Cao College of mining Liaoning Technical UniversityFuxin123000China University of Wollongong EISNSWWollongong2522Australia Liaoning province Coal Resources Safety mining and Clean Utilization engineering research center Fuxin123000China

Coal bump seriously threatens the safe and efficient mining of coal,and the research on the occurrence mechanism of coal bump is of great *** roadway coal bump accounts for 86.8%of the *** occurrence of coal bump in gateroad is *** is considered that hard roof and hard coal are the geological characteristics of coal bump,and the sliding instability of rib coal mass is the failure characteristics of coal *** on the elastic foundation theory,the upward deflection characteristics of the front and lateral roof of the working face under the condition of hard roof are analyzed,and compared with the engineering practice of roof *** the roadway coal mass as the research object,the unloading sliding mechanical model of roof-coal-floor composite structure is *** analyzing the relationship between horizontal ground stress of coal mass,frictional force of coal-roof and coal-floor and tensile resistance of coal mass,the critical equation of coal bump is *** is proposed that the vertical pressure of coal seam is reduced due to the upward deflection of the roof,and the coal mass loses its clamping and moves into the roadway after overcoming the friction between roof and floor and the tensile strength of coal mass under the action of horizontal ground stress,that is,the unloading and slippage mechanism of coal bump in hard roof mining *** model reasonably explains the causality of coal bump in hard roof mining *** on the unloading-slippage model,the principle of influencing factors of coal bump,includes the buried depth,roof strength,roof elastic modulus and roof thickness,coal mass strength and elastic ***,two coal bump events,''8.2''coal bump in Tangshan coal mine and''11.11''coal bump in Hongyang mine are analyzed and the unloading-slippage mechanism are the reasoning of two events.

关键词： Hard roof Gateroad Coal bump Elastic foundation Unloading Slippage

Adsorption mechanism of styryl phosphonate ester as collector in ilmenite flotation

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Transactions of Nonferrous Metals Society of China 2022年第12期32卷 4088-4098页

作者： Yan-ling XU Kai-hua HUANG Hong-qiang LI Wei HUANG Cheng LIU Si-yuan YANG School of Resources and Environmental engineering Wuhan University of TechnologyWuhan 430070China South China Institute of Environmental Sciences Ministry of Ecology and EnvironmentGuangzhou 510530China engineering research center of Phosphorus Resources Development and Utilization of Ministry of Education Wuhan Institute of TechnologyWuhan 430205China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China

A styryl phosphonate ester(SPE) collector was used to improve the flotation performance of ilmenite, and the adsorption mechanism and model were revealed and established, respectively. Microflotation tests showed that SPE exhibited a stronger collecting ability for ilmenite than the traditional collector styrene phosphonic acid(SPA). Zeta potential measurements revealed that both SPE and SPA could negatively shift the zeta potential of ilmenite, while SPE had more effects than SPA, suggesting the stronger adsorption of SPE. The analysis of X-ray photoelectron spectroscopy confirmed the chemisorption of SPA and SPE onto the Fe/Ti sites of ilmenite. According to frontier orbital theory, the chemical activities of SPE are greater than those of SPA. The partial densities of states analysis indicated that the PO—H groups of the collectors could interact with the Ti/Fe atoms of the ilmenite surface to generate a stable four-membered ring. The bonding model of the collector and(104) ilmenite surface showed that the adsorption energy of SPE was higher than that of SPA. Overall, SPE presented a better collecting ability and interaction effect for ilmenite flotation than SPA, and had the potential to replace SPA in the industry.

关键词： styryl phosphonate ester ilmenite flotation collector X-ray photoelectron spectroscopy density functional theory adsorption mechanism

Influence of freeze tube deviation on the development of frozen wall during long cross-passage construction

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research in Cold and Arid Regions 2022年第4期14卷 250-257页

作者： JunHao Chen JianLin Wang LeXiao Wang Han Li MeiLin Chen School of Civil engineering Fujian University of TechnologyFuzhouFujian350118China Key Laboratory of Underground engineering Fujian Province UniversityFuzhouFujian350118China

This paper investigates the influence of the deviation in freeze pipe installation on the development of the frozen wall in long cross passages by numerical simulation with ANSYS *** study case is from the artificial ground freezing project along the Fuzhou Metro Line 2 between Ziyang Station and Wuliting *** freezepipe configurations,i.e.,one with perfectly aligned pipes without any deviation from design and another with randomly distributed deviation,are included for *** effect of the random deviation in the freeze pipes on frozen wall interconnection time,the thickness of the frozen wall and the development of the temperature field is *** the characteristic section of the numerical model at a depth of 25 m,it is found that the frozen wall interconnection time under the random deviation case and no deviation case is 24 days and 18 days,*** difference in the thickness of the thinnest frozen wall segment between the random deviation and no deviation cases is the largest in the early freezing stage(up to 0.75 m),which decreases with time to 0.31 m in the late freezing *** effects of random deviation are more significant in the early freezing stage and diminish as the freezing time increases.

关键词： Long cross passages Artificial ground freezing Random deflection Numerical simulation

Influence of temperature on thermal relaxation of exchange bias field in CoFe/Cu/CoFe/IrMn spin valve

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Chinese Physics B 2021年第10期30卷 554-559页

作者： Xian-Jin Qi Ni-Na Yang Xiao-Xu Duan Xue-Zhu Li engineering research center of Metallurgical Energy Conservation and Emission Reduction Ministry of EducationKunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China

A multilayered spin valve film with a structure of Ta(5 nm)/Co_(75)Fe_(25)(5 nm)/Cu(2.5 nm)/Co_(75)Fe_(25)(5 nm)/Ir_(20)Mn_(80)(12 nm)/Ta(8 nm)is prepared by the high-vacuum direct current(DC)magnetron *** effect of temperature on the spin valve structure and the magnetic properties are studied by x-ray diffraction(XRD),atomic force microscopy(AFM),and vibrating sample *** effect of temperature on the exchange bias field thermomagnetic properties of multilayered spin valve is studied by the residence time of samples in a reverse saturation *** results show that as the temperature increases,the IrMn(111)texture weakens,surface/interface roughness increases,and the exchange bias field *** 200℃,the exchange bias field decreases with the residence time increasing,and at the beginning of the negative saturation field,the exchange bias field Hex decreases first quickly and then slowly *** the temperature is greater than 200℃,the exchange bias field is unchanged with the residence time increasing.

关键词： exchange bias field spin valves temperature thermal relaxation

Effect of diet on the development, survival, and reproduction of the calanoid copepod Pseudodiaptomus dubia

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Journal of Oceanology and Limnology 2019年第5期37卷 1756-1767页

作者： LUO Xiaoxia LI Changling HUANG Xianghu Department of Aquaculture Fishery CollegeGuangdong Ocean UniversityZhanjiang 524088China engineering technology research center for Algae Breeding and Application Zhanjiang 524088China Shenzhen research Institute of Guangdong Ocean University Shenzhen 518108China

Pseudodiaptomus dubia is a calanoid copepod abundant in the mariculture ponds of southern China. However, our understanding of the population dynamics of P . dubia in aquaculture ponds is limited. In this study, groups of larval P . dubia were each fed a diff erent microalgal species, and the eff ects of these diff erent diets on development, survival, and reproduction were assessed. The fi ve microalgae used were species common in aquaculture farms in China, and included two chlorophytes ( Chlorella saccharophila and Platymonas subcordiformis ), one golden microalga ( Isochrysis zhanjiangensis ), and two diatoms ( Chaetoceros muelleri and Cyclotella meneghiniana ). Our results indicated that C . saccharophila was not a suitable food for larval P . dubia , as all larvae fed this microalga died at stage III (as copepodites). The survival rates of P . dubia larvae fed C . muelleri , I . zhanjiangensis , and P . subcordiformis were signifi cantly higher than that of larvae fed C . meneghiniana . In the adult stage, copepods fed C . muelleri , I . zhanjiangensis , and C . meneghiniana produced more nauplii (430-566 nauplii/female), had higher intrinsic growth rates (0.2- 0.253/d), and better longevity (59-60 days) than those fed P . subcordiformis . Our results therefore suggest that P . dubia has diff erent nutritional needs and food preferences at diff erent life stages. For example, P . subcordiformis was suitable for developing larvae but not for breeding adults, while C . meneghiniana was suitable for breeding adults but not for developing larvae. Both C . muelleri and I . zhanjiangensis were excellent foods for P . dubia throughout the entire life cycle.

关键词： copepods development survival reproduction Pseudodiaptomus dubia diet