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Numerical and experimental investigation on hydraulic-electric rock fragmentation of heterogeneous granite

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International Journal of Mining Science and Technology 2024年第1期34卷 15-29页

作者： xiaohua Zhu Ling He Weiji Liu Yunxu Luo Youjian Zhang Wuji tang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China School of Mechanical Engineering Sichuan University of Science and EngineeringYibin 643002China

Hydraulic-electric rock fragmentation(HERF)plays a significant role in improving the efficiency of high voltage pulse rock breaking.However,the underlying mechanism of HERF remains unclear.In this study,considering the heterogeneity of the rock,microscopic thermodynamic properties,and shockwave time domain waveforms,based on the shockwave model,digital imaging technology and the discrete element method,the cyclic loading numerical simulations of HERF is achieved by coupling electrical,thermal,and solid mechanics under different formation temperatures,confining pressure,initial peak voltage,electrode bit diameter,and loading times.Meanwhile,the HERF discharge system is conducive to the laboratory experiments with various electrical parameters and the resulting broken pits are numerically reconstructed to obtain the geometric parameters.The results show that,the completely broken area consists of powdery rock debris.In the pre-broken zone,the mineral cementation of the rock determines the transition of type CⅠcracks to type CⅡand type CⅢcracks.Furthermore,the peak pressure of the shockwave increased with initial peak voltage but decreased with electrode bit diameter,while the wave front time reduced.Moreover,increasing well depth,formation temperature and confining pressure augment and inhibit HERF,but once confining pressure surpassed the threshold of 60 MPa for 152.40,215.90,and 228.60 mm electrode bits,and 40 MPa for 309.88 mm electrode bits,HERF is promoted.Additionally,for the same kind of rock,the volume and width of the broken pit increase with higher initial peak voltage and rock fissures will promote HERF.Eventually,the electrode drill bit with a 215.90 mm diameter is more suitable for drilling pink granite.This research contributes to a better microscopic understanding of HERF and provides valuable insights for electrode bit selection,as well as the optimization of circuit parameters for HERF technology.

关键词： Hydraulic-electric rock fragmentation Shockwave Thermodynamics Microcracks Weak Linear Parallel Bond Model

Urban growth scenario projection using heuristic cellular automata in arid areas considering the drought impact

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Journal of Arid Land 2024年第4期16卷 580-601页

作者： tang Xiaoyan FENG Yongjiu LEI Zhenkun CHEN Shurui WANG Jiafeng WANG Rong tang Panli WANG Mian JIN Yanmin TONG xiaohua College of Surveying&Geo-Informatics Tongji UniversityShanghai 200092China Shanghai Key Laboratory of Space Mapping and Remote Sensing for Planetary Exploration Tongji UniversityShanghai 200092China

Arid areas with low precipitation and sparse vegetation typically yield compact urban pattern,and drought directly impacts urban site selection,growth processes,and future scenarios.Spatial simulation and projection based on cellular automata(CA)models is important to achieve sustainable urban development in arid areas.We developed a new CA model using bat algorithm(BA)named bat algorithm-probability-of-occurrence-cellular automata(BA-POO-CA)model by considering drought constraint to accurately delineate urban growth patterns and project future scenarios of Urumqi City and its surrounding areas,located in Xinjiang Uygur Autonomous Region,China.We calibrated the BA-POO-CA model for the drought-prone study area with 2000 and 2010 data and validated the model with 2010 and 2020 data,and finally projected its urban scenarios in 2030.The results showed that BA-POO-CA model yielded overall accuracy of 97.70%and figure-of-merits(FOMs)of 35.50%in 2010,and 97.70%and 26.70%in 2020,respectively.The inclusion of drought intensity factor improved the performance of BA-POO-CA model in terms of FOMs,with increases of 5.50%in 2010 and 7.90%in 2020 than the model excluding drought intensity factor.This suggested that the urban growth of Urumqi City was affected by drought,and therefore taking drought intensity factor into account would contribute to simulation accuracy.The BA-POO-CA model including drought intensity factor was used to project two possible scenarios(i.e.,business-as-usual(BAU)scenario and ecological scenario)in 2030.In the BAU scenario,the urban growth dominated mainly in urban fringe areas,especially in the northern part of Toutunhe District,Xinshi District,and Midong District.Using exceptional and extreme drought areas as a spatial constraint,the urban growth was mainly concentrated in the"main urban areas-Changji-Hutubi"corridor urban pattern in the ecological scenario.The results of this research can help to adjust urban planning and development policies.Our model is readily applicable to simulating urban grow

关键词： bat algorithm cellular automata(CA) probability-of-occurrence drought intensity algorithm-probability-of-occurrence-cellular automata(BA-POO-CA)model arid areas

Nutrient enrichment driven by canopy rainfall redistribution:Mechanism,quantification,and pattern

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Science China Earth Sciences 2024年第5期67卷 1529-1544页

作者： Chuan YUAN Xiaoping YUE Yafeng ZHANG Yu ZHANG Yanting HU Qiang tang Li GUO Shuai WANG Xingwu DUAN Wenhua XIANG xiaohua WEI Xiaoyan LI College of Forestry and Biotechnology Zhejiang A&F UniversityHangzhou 311300China Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station School of Geographical SciencesSouthwest UniversityChongqing 400715China Shapotou Desert Research and Experiment Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Geographical Sciences Hebei Normal UniversityShijiazhuang 050024China Faculty of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Institute of International Rivers and Eco-securityYunnan UniversityKunming 650091China Department of Earth Environmental and Geographic SciencesUniversity of British Columbia(Okanagan)KelownaBritish Columbia V1V 1V7Canada

Vegetation canopies intercept and redistribute rainfall into throughfall and stemflow,which transfer substantial amounts of elements into the soil,influencing soil microbial community,plant survival,and plant community succession.Despite advancements in ecohydrological research,the implication of nutrient enrichment resulting from this redistribution of rainfall by canopies remains largely unexplored.To address this gap,we conducted a systematic review of 1020 papers published between 2000 and 2022,gathering data on nutrient concentration and enrichment for critical ions(including K^(+),Na^(+),Ca^(2+),Mg^(2+),NH_(4)^(+),Cl^(-),NO_(3)^(-)and SO_(4)^(2-))from the Web of Science and Chinese Knowledge Infrastructure databases.We aimed to synthesize the mechanisms,quantify the enrichments,and identify global patterns of nutrient enrichment in stemflow and throughfall across climate zones,and vegetation types and ecosystems.The results of this study indicate that stemflow exhibits,on average,2.1times greater ion concentration(6.13 mg L^(-1))compared to throughfall.In particular,among the investigated ions,SO_(4)^(2-)(12.45and 6.32 mg L^(-1))for stemflow and throughfall,respectively,and Cl^(-)(9.21 and 4.81 mg L^(-1))exhibit the highest concentrations in both rainfall redistribution components,while K^(+)(13.7 and 5.8)and Mg^(2+)(5.6 and 2.8)have the highest enrichment factors.Across climate zones,throughfall and stemflow show the lowest ion concentrations but the highest enrichment factors in extremely humid regions.Along the temperature gradient,ion concentrations are the highest in cold climates with no clear patterns observed for enrichment factors with increasing temperature.In addition,shrubs,conifers,mixed forests,and artificial ecosystems demonstrate enrichment factors 1.1 to 3.0 times greater than those of trees,broad-leaved plants,pure forests,and natural ecosystems.These findings emphasize the need for increased attentions to artificial ecosystems,such as urban and agricultural ecosystems,which often received

关键词： Ecohydrology Rainfall redistribution Nutrients transport Enrichment characteristics Climate zones

Chlamydia trachomatis infection in the genital tractis associated with inflammation and hypospermia inthe infertile male of China

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Asian Journal of Andrology 2022年第1期24卷 56-61页

作者： Hua Zhou Shunhong Wu xiaohua tang Guanqing Zhou Jingru Yuan Qing Li Yaoyong Chen Xia Xu Xiaofang Sun Detu Zhu Yumei Luo Department of Obstetrics and Gynecology Key Laboratory for Major Obstetric Diseases of Guangdong ProvinceThe Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510150China Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes The Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510150China Kingmed School of Laboratory Medicine Guangzhou Medical UniversityGuangzhou 510182China Department of Clinical Laboratory The Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510150China

Chlamydia trachomatis (CT) infection is the most prevalent sexually transmitted bacterial disease worldwide. However, unlikethat in female infertility, the role of CT infection in male infertility remains controversial. The objective of this retrospective studywas to explore the impacts of CT infection in the genital tract on sperm quality, sperm acrosin activity, antisperm antibody levels,and inflammation in a large cohort of infertile males in China. A total of 7154 semen samples were collected from infertile malesubjects, 416 of whom were CT positive (CT+ group) and 6738 of whom were CT negative (CT− group), in our hospital betweenJanuary 2016 and December 2018. Routine semen parameters (semen volume, pH, sperm concentration, viability, motility,morphology, etc.), granulocyte elastase levels, antisperm antibody levels, and sperm acrosin activity were compared between theCT+ and CT− groups. Our results showed that CT infection was significantly correlated with an abnormally low semen volume, aswell as an increased white blood cell count and granulocyte elastase level (all P < 0.05) in the semen of infertile males;otherroutine semen parameters were not negatively impacted. The antisperm antibody level and sperm acrosin activity were not affectedby CT infection. These findings suggested that CT infection might contribute to inflammation and hypospermia but does not impairsperm viability, motility morphology, and acrosin activity or generate antisperm antibodies in the infertile males of China.

关键词： Chlamydia trachomatis genital tract obstruction hypospermia male infertility semen parameters sperm quality

数字化转型对制造企业绿色创新效率作用机制研究

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金融与经济 2024年第4期 85-94页

作者：李鑫鑫汤小华北京交通大学经济管理学院

选用沪深A股上市的2039家制造企业2010—2021年的数据,探究数字化转型对绿色创新效率的影响及其作用机制。研究结果表明,制造企业进行数字化转型对绿色创新效率的提高有显著正向影响。进一步研究发现,企业主要通过加大创新资源投入、缓... 详细信息

选用沪深A股上市的2039家制造企业2010—2021年的数据,探究数字化转型对绿色创新效率的影响及其作用机制。研究结果表明,制造企业进行数字化转型对绿色创新效率的提高有显著正向影响。进一步研究发现,企业主要通过加大创新资源投入、缓解融资约束的方式来发挥数字化转型对绿色创新效率的提高作用;企业社会责任正向调节了数字化转型与绿色创新效率的关系;非国有、有政治关联、东部地区的制造企业进行数字化转型对促进绿色创新效率的提高作用更显著。

关键词：创新资源投入融资约束企业社会责任

2010—2021年中国森林生态系统服务功能价值评估研究进展

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生态学杂志 2024年第1期43卷 244-253页

作者：杨海江勾晓华唐呈瑞薛冰兰州大学资源环境学院西部环境教育部重点实验室兰州730000 兰州大学甘肃连城森林生态系统野外科学观测研究站兰州730333 中国科学院沈阳应用生态研究所污染生态与环境工程重点实验室沈阳110016

科学评估森林生态系统服务功能价值有利于实现森林资源资产化、优化森林资源保护和管理模式。通过对2010—2021年相关文献进行梳理,总结了中国森林生态系统服务功能价值评估研究进展。中国森林生态系统不同服务功能的价值量存在显著差异... 详细信息

科学评估森林生态系统服务功能价值有利于实现森林资源资产化、优化森林资源保护和管理模式。通过对2010—2021年相关文献进行梳理,总结了中国森林生态系统服务功能价值评估研究进展。中国森林生态系统不同服务功能的价值量存在显著差异,从大到小依次为涵养水源、保育土壤、固碳释氧、生物多样性保护、净化空气、森林游憩、林木产品供给、森林防护和林木养分固持。山地森林生态系统和城市森林生态系统的服务功能具有异质性,山地森林的主要贡献为涵养水源(36.94%)、保育土壤(18.68%)、生物多样性保护(17.67%)和固碳释氧(12.44%),而城市森林的主要贡献为固碳释氧(29.37%)、涵养水源(22.49%)、净化空气(16.93%)和保育土壤(11.68%)。不同类型森林的生态系统服务功能价值从大到小依次为常绿阔叶林、落叶阔叶林、针阔混交林和针叶林。2010—2021年,中国森林生态系统服务价值评估的方法体系和评估指标在不断充实和完善,但仍然存在很多不足,尤其是在指标体系一致性构建方面。未来,需进一步优化计量方法和技术手段,提高数据获取能力,提升生态系统服务功能评估的完整性和科学性,从而为森林生态系统可持续经营与生态环境建设提供科学依据,为生态系统服务价值的实现路径研究奠定基础。

关键词：森林生态系统生态系统服务价值评估指标体系生态系统管理

竹圈姜灸联合中药热熨在慢性非特异性腰痛病人中的应用

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护理研究 2024年第7期38卷 1308-1310页

作者：尹小花汤霞赵丹江西中医药大学附属医院江西330006

目的:探究竹圈姜灸联合中药热熨对慢性非特异性腰痛病人的疗效。方法:选取2022年1月—2023年1月我院收治的88例慢性非特异性腰痛病人,采用随机数字表法将其分为对照组和观察组,各44例。对照组给予常规护理,观察组给予竹圈姜灸联合中药... 详细信息

目的:探究竹圈姜灸联合中药热熨对慢性非特异性腰痛病人的疗效。方法:选取2022年1月—2023年1月我院收治的88例慢性非特异性腰痛病人,采用随机数字表法将其分为对照组和观察组,各44例。对照组给予常规护理,观察组给予竹圈姜灸联合中药热熨护理。比较两组护理4周后的护理有效率及护理前、护理4周视觉模拟评分法(VAS)评分、Oswestry功能障碍指数(ODI)评分、匹兹堡睡眠质量指数(PSQI)评分。结果:护理4周后,观察组总有效率高于对照组;VAS评分、ODI评分、PSQI评分低于护理前及对照组,差异均有统计学意义(P<0.05)。结论:竹圈姜灸联合中药热熨可缓解慢性非特异性腰痛病人的疼痛感,改善其腰椎功能及睡眠质量,提高其护理效果。

关键词：慢性非特异性腰痛竹圈姜灸中药热熨疼痛睡眠质量中医护理

SBA-15分子筛负载对甲苯磺酸催化合成过氧化二异丙苯的性能和反应过程模拟

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高等学校化学学报 2024年第6期45卷 98-106页

作者：张小龙张毅城李庆朝查飞常玥唐小华西北师范大学化学化工学院兰州730070 山东阳谷华泰化工股份有限公司阳谷252300

采用浸渍法制备了SBA-15分子筛负载对甲苯磺酸(TsOH)催化剂TsOH/SBA-15,探究了其催化α-甲基苯乙烯(α-MS)和异丙苯过氧化氢(CHP)反应制备过氧化二异丙苯(DCP)的活性,并对反应过程进行了模拟分析.当进料比n(α-甲基苯乙烯)/n(异丙苯过... 详细信息

采用浸渍法制备了SBA-15分子筛负载对甲苯磺酸(TsOH)催化剂TsOH/SBA-15,探究了其催化α-甲基苯乙烯(α-MS)和异丙苯过氧化氢(CHP)反应制备过氧化二异丙苯(DCP)的活性,并对反应过程进行了模拟分析.当进料比n(α-甲基苯乙烯)/n(异丙苯过氧化氢)=2.0, TsOH/SBA-15用量为CHP质量的0.15%,于44℃反应2.5h, DCP的产率为62.1%.模拟计算结果表明,反应过程有异步协同反应和分步反应两种机理,在异步协同反应中α-MS, CHP和TsOH只需要经过一个过渡态即可完成,而分步反应中反应物需要经过两个过渡态以及一个中间体才能完成,两种路径均涉及2次H^(+)的转移.在44℃下,异步协同反应的反应能垒(ΔG)为121.8 kJ/mol,分步反应中两个过渡态对应的反应能垒分别为74.1和78.3 kJ/mol.

关键词：对甲苯磺酸 SBA-15分子筛过氧化二异丙苯异丙苯过氧化氢反应能垒

双循环视角下高铁建设对制造企业服务融合的影响研究

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中国软科学 2024年第6期 111-120页

作者：王昀付琳唐卓伟孙晓华大连理工大学经济管理学院辽宁大连116021

从国内国际双循环的新视角探究高铁建设对制造企业服务融合的影响。结果发现:高铁建设对制造企业服务融合存在显著正向影响;高铁促进了制造企业嵌入式服务水平提升,显著减少混入式服务融合;高铁建设通过国内市场可达性与市场竞争的增加... 详细信息

从国内国际双循环的新视角探究高铁建设对制造企业服务融合的影响。结果发现:高铁建设对制造企业服务融合存在显著正向影响;高铁促进了制造企业嵌入式服务水平提升,显著减少混入式服务融合;高铁建设通过国内市场可达性与市场竞争的增加促进制造企业服务融合;国际市场可达性和市场竞争的增加不利于制造企业服务化转型。

关键词：高铁建设国内国际双循环制造企业服务融合