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The Role of China's High-Tech Zones in Its Regional Economic Development 被引量:2
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作者 刘瑞明 赵仁杰 《China Economist》 2016年第5期44-56,共13页
National high-tech industrial development zones represent a major strategy of the Chinese government in developing high-tech industries and spurring regional economic growth. The effect of this policy is yet to be pro... National high-tech industrial development zones represent a major strategy of the Chinese government in developing high-tech industries and spurring regional economic growth. The effect of this policy is yet to be proven. Based on the panel data of 283 Chinese cities between 1984 and 2012, this paper investigates the effect of high-tech zones on regional economic development. Empirical results suggest that first, national hightech zones have remarkably enhanced regional GDP and per capita GDP growth, and this conclusion still holds true after multiple rounds of robustness test; second, the economic effect of national high-tech zones is subject to diminishing marginal return and compared with higher-tier cities, lower-tier cities benefited more from the creation of national hightech zones. This paper concludes that national high-tech zones where special policies are experimented and offered not only drive economic development but, if properly distributed across regions, may help reduce regional economic disparities as well. The results of this study provide important implications for the future distribution of national high-tech zones and the creation of other relevant policies. 展开更多
关键词 national high-tech zones regional economic growth difference-in-differences method
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Comprehensive Control Measures and Effect Evaluation of Groundwater Over-exploitation Areas in High-tech Zone,Jining in 2020
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作者 Shengqing LI Fei XIE 《Meteorological and Environmental Research》 CAS 2022年第3期82-85,共4页
Groundwater over-exploitation is a major problem in groundwater development, utilization and protection. At present, the area of shallow groundwater over-exploitation in the High-tech Zone is 76 km^(2). In this study,... Groundwater over-exploitation is a major problem in groundwater development, utilization and protection. At present, the area of shallow groundwater over-exploitation in the High-tech Zone is 76 km^(2). In this study, the system and mechanism construction, engineering measure construction, and control effect of national comprehensive control project of groundwater over-exploitation areas in the High-tech Zone in 2020 were evaluated, and the comprehensive control of groundwater over-exploitation in the High-tech Zone in the year was summarized to provide effective basis for the continuous implementation of comprehensive control of groundwater over-exploitation. At the same time, the water-saving and exploitation reduction effect and generalizability of different measures were studied to provide useful reference for other over-exploitation areas. 展开更多
关键词 GROUNDWATER Over-exploitation area Exploitation reduction effect high-tech zone Jining
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Evolution of Industrial Competitiveness Based on Evaluation of Urban Competitiveness of Dongguan City:A Case Study of Songshan Lake High-tech Zone
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作者 TANG Shiyu LU Bin HE Dongran 《Journal of Landscape Research》 2020年第3期57-64,共8页
Based on the theoretical system of urban competitiveness,the evaluation model of urban competitiveness from the perspective of competition and cooperation was established.According to the significance index and explan... Based on the theoretical system of urban competitiveness,the evaluation model of urban competitiveness from the perspective of competition and cooperation was established.According to the significance index and explanatory index,the urban competitiveness was divided into urban comprehensive competitiveness(UC),urban internal node competitiveness(NC)and external competitiveness of urban network(EC).The scores and rankings of UC,NC and EC in 2006,2010 and 2015 were obtained by conducting the comprehensive evaluation of the urban competitiveness of Dongguan City with integrated usage of the principal component analysis and Technique for Order Preference by Similarity to an Ideal Solution and the data of other 20 cities in Guangdong province,Hong Kong and Macao.The research showed that the competitiveness of Dongguan City has been greatly improved during the decade of 2006–2015,and the regional cities in Guangdong Province had significant differences,which are reflected in the two dimensions of urban internal node competitiveness(NC)and external competitiveness of urban network(EC).Based on this,this study further analyzed Dongguan’s urban competitiveness from two dimensions of NC and EC,and took Dongguan Songshan Lake High-tech Zone as an example to study how to promote Dongguan’s urban competitiveness from the industrial level. 展开更多
关键词 Dongguan Songshan Lake high-tech zone External competitiveness of urban network Improvement of comprehensive competitiveness
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Characteristics and Development Modes of Standardization forChina's National High-Tech Zones:A Review
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作者 郑巧英 田川 徐成华 《China Standardization》 2012年第2期52-57,共6页
Indigenous innovation focused on the development of technical standards has become the core of China's innovation policy,since China released the "Outline of the National Program for Longand Medium-Term Scien... Indigenous innovation focused on the development of technical standards has become the core of China's innovation policy,since China released the "Outline of the National Program for Longand Medium-Term Scientific and Technological Development (2006-2020)" in 2006.Meanwhile,standardization issues are greatly emphasized by high-tech zones which serve as the major carriers of national economic growth as well as innovation clusters in the context of fast-growing international standardization.By means of the effective guide of the government,the standardization of high-tech zones in China now presents a wide range of operating modes.Specifically,they can be divided predominantly into the government promotion mode,the alliance collaboration mode,the research-standard-industry linkage mode,and the talent training mode,in terms of the main body of work and influence factors. 展开更多
关键词 National high-tech zone STANDARDIZATION standard development modes
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Chengdu High-Tech Zone
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《China Today》 2001年第4期28-29,共2页
关键词 Chengdu high-tech zone
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A Study on Theoretical Model and Applied Evaluation of Land Use Performance of High-tech Zone in Urban Fringe: A Case Study in Haidian District, Beijing 被引量:3
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作者 Ban Maosheng Fang Chuanglin Liu Xiaoli 《Chinese Journal of Population,Resources and Environment》 北大核心 2008年第1期91-96,共6页
High-tech industrial zone is an important carrier for constructing innovative cities. It also plays an important role in implementing the national independent innovative strategy. How-ever, most of the high-tech indus... High-tech industrial zone is an important carrier for constructing innovative cities. It also plays an important role in implementing the national independent innovative strategy. How-ever, most of the high-tech industrial zones have many problems in their development process, such as efficiency of land use, weakness of oriented function and lack of land intensive. To solve these problems, the authors of this paper introduced the concept of land use performance and established the theoretical model to assess the land use performance of high-tech industrial zones. The model consists of the following three-dimensional parts: land use benefit, land use efficiency and innovative function. Based on this theory model, an index system which was composed of three secondary indictors, eight tertiary indictors and 37 fourth-grade indictors was set up to evaluate the land use performance of high-tech zone. To avoid the defects of plus model and function model, the authors brought out a three-dimensional evaluation model to examine the index of the land use performance of the high-tech industrial parks, which equals to the evaluation indicator system of land use performance of high-tech zone based on the above research. The authors examined the land use performance of five different high-tech industrial parks in Haidian District, Beijing City. The results indicated that the indicator system per-forms better in the aspect of evaluating land use benefit, land use efficiency and function of the high-tech industrial zone compared with other models. 展开更多
关键词 high-tech industry zone innovative ability land use performance theoretical mode
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Particulate matter pollution in Kunshan High-Tech zone: Source apportionment with trace elements, plume evolution and its monitoring 被引量:3
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作者 Suwei Zhang Qijie Zhang +11 位作者 Armand Albergel Didier Buty Liangmin Yu Haiting Wang Wuxia Bi Peng Cheng Fu Chen Jun Fang Ruirui Hou Xudong Luan Changgan Shu Jingjing Su 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第9期119-126,共8页
Particulate matter (PM} in the Kunshan High-Tech zone is studied during a three-month campaign. PM and trace elements are measured by the online pollution monitoring, forecast-warning and source term retrieval system... Particulate matter (PM} in the Kunshan High-Tech zone is studied during a three-month campaign. PM and trace elements are measured by the online pollution monitoring, forecast-warning and source term retrieval system AS3. Hourly measured concentrations of PM10, PM2.5 and 16 trace elements in the PM2.5 section (Ca, Pb, Cu, C1, V, Cr, Fe, Ti, Mn, Ni, Zn, Ga, As, Se, Sr, Ba) are focused. Source apportionment of trace elements by Positive Matrix Factorization modeling indicates that there are five major sources, including dust, industrial processing, traffic, combustion, and sea salt with contribution rate of 23.68%, 21.66%, 14.30%, 22.03%, and 6.89%, respectively. Prediction ofptume dispersion from concrete plant and traffic emissions shows that PM20 pollution of concrete plant is three orders of magnitude more than that of the traffic. The influence range can extend to more than 3 km in 1 hr. Because the footprint of the industrial plumes is constantly moving according to the local meteorological conditions, the fixed monitoring sites scattered in a few hundred meters haven't captured the heaviest pollution plume at the local scale of a few km2. As a more intensive monitoring network is not operationally possible, the use of online modeling gives accurate and quantitative information of plume location, which increases the spatial pollution monitoring capacity and improves the understanding of measurement data. These results indicate that the development of the AS3 system, which combines monitoring equipment and air pollution modeling systems, is beneficial to the real-time pollution monitoring in the industrial zone. 展开更多
关键词 Particulate matter pollution Trace elements Online pollution monitoring in a industrial zone Source apportionment Plume evolution
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The Impact of the Establishment of National High-tech Zones on Total Factor Productivity of Chinese Enterprises
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作者 Wang Mingyi Liu Xiaoyu 《中国经济学人(中英文)》 2023年第3期68-93,共26页
The National High-tech Zone(NHTZs)is an important strategic platform for cultivating high-tech industries and realizing high-quality economic development in China.Based on the combined data from 2006 to 2014 of the in... The National High-tech Zone(NHTZs)is an important strategic platform for cultivating high-tech industries and realizing high-quality economic development in China.Based on the combined data from 2006 to 2014 of the industrial enterprise database,the customs database,and the China Development Zones Audit and Announcement Catalogue(abbreviated asthe Catalogue),this paper systematically investigates the influence of the construction of NHTZs on enterprise’s total factor productivity(TFP).Results show that NHTZs have a positive impact on the TFP of enterprises in the zone,and this conclusion is still valid after considering endogeneity problems.Furthermore,the above productivity effects of NHTZs are heterogeneous in terms of enterprise ownership,external environment and establishment time,and NHTZs have greater stimulation effects on enterprise productivity after comparing with other types of functional zones.An investigation of the specific mechanisms at play shows that NHTZs promote the TFP of enterprises in the zone through the release of preferential policies,strengthening the“technology spillover effects”of imported intermediate goods,enhancing enterprise’s innovation ability and attracting talent.In addition,based on the decomposition of industry productivity,this paper also investigates the impact of NHTZs on changes in industry productivity and finds that NHTZs promote the overall productivity of specific industries mainly by stimulating the productivity improvement of incumbent enterprises and expanding the market share of high-productivity enterprises.Moreover,the preferential policies of NHTZs do not significantly stimulate high-productivity enterprises to enter the zones,nor do they cause low-productivity enterprises to exit.This research is helpful in objectively evaluating the economic effects of the NHTZs in China and in providing a theoretical basis for its further adjustment. 展开更多
关键词 National high-tech zones(NHTZs) total factor productivity(TFP) difference-in-differences changes in industry productivity
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Preparation of high-purity tellurium based on simulation-assisted zone refining
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作者 Qing-hua TIAN Zhi-qiang HE +2 位作者 Zhi-peng XU Hai-bei WANG Liu ZHU 《Transactions of Nonferrous Metals Society of China》 2026年第2期638-648,共11页
The effect of temperature on molten zone length was investigated through simulation to optimize the control of molten zone length during the experimental process. The temperature gradient distribution within the molte... The effect of temperature on molten zone length was investigated through simulation to optimize the control of molten zone length during the experimental process. The temperature gradient distribution within the molten zone during zone refining was simulated using COMSOL Multiphysics software and experimentally validated. The simulated molten zone length showed good agreement with the actual measured length. The experimental study of tellurium purification by zone refining was conducted under the following conditions: three passes of zone refining, a hydrogen flow rate of 0.5 L/min, and molten zone movement speeds of 0.5 and 1.0 mm/min. The results demonstrated that the removal efficiencies of impurities such as Ca and Cu exceeded 95%, while the removal efficiency of phosphorus (P) reached over 70%. And the purity of tellurium reached 6N. 展开更多
关键词 high purity tellurium SIMULATION zone refining molten zone length
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Agro-Climatic Suitability of Purslane(Portulaca oleracea L.)under Abiotic Stress in Semiarid—Arid Zone in North America
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作者 Aaron David Lugo-Palacios Edgar Omar Rueda-Puente +3 位作者 César Omar Montoya-García Ignacio Orona-Castillo Urbano Nava-Camberos JoséLuis García-Hernández 《Phyton-International Journal of Experimental Botany》 2026年第1期234-250,共17页
To ensure the efficient use of resources,particularly in water-scarce arid and semi-arid regions where abiotic stress threatens food security,assessing soil and climate suitability for specific crops is crucial.Simult... To ensure the efficient use of resources,particularly in water-scarce arid and semi-arid regions where abiotic stress threatens food security,assessing soil and climate suitability for specific crops is crucial.Simultaneously,food production must align with sustainable development goals by minimizing negative environmental impacts.Therefore,establishing agro-climatic suitability using a spatiotemporal approach is essential.This involves three key steps:first,determining the climatically appropriate months based on the species’requirements(temporal suitability),and second,establishing the soil suitability of specific plots(spatial suitability).Following this,quantifying crop evapotranspiration allows for optimized water use.This study used climatic and soil variables from diverse data sources to characterize the study area.Subsequently,suitability classes for Portulaca oleracea were determined based on existing literature.Our analysis concerning temporal suitability revealed that June and July are the optimal months for sowing this species in all of the municipalities.Spatially,approximately 30%of the agricultural land use of the study area exhibits a highly suitable class in most municipalities.Both dimensions,the temporal and the spatially,were validated through Chi square(χ^(2))Goodness-of-Fit test and theχ^(2)test of independence,respectively.Consequently,for a one-month production cycle during periods of high suitability,estimated evapotranspiration values are between 210 and 245 mm.In brief,the study area demonstrates favorable agro-climatic conditions for P.oleracea cultivation in specific months of the year according to parameters used,with potential in a large proportion of agricultural land and achievable water requirements. 展开更多
关键词 HALOPHYTE agro-ecological zoning northern Mexico spatio-temporal suitability
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Prediction of Root Zone Temperature Dynamics at Effective Depth on Lettuce Production in Greenhouse Using Sensitivity and Feature Importance Analysis with XGBoost
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作者 Hasan Kaan Kucukerdem 《Phyton-International Journal of Experimental Botany》 2026年第1期265-289,共25页
Root-zone temperature(RZT)strongly affects plant growth,nutrient uptake and tolerance to environmental stress,making its regulation a key challenge in greenhouse cultivation in cold climates.This study aimed to assess... Root-zone temperature(RZT)strongly affects plant growth,nutrient uptake and tolerance to environmental stress,making its regulation a key challenge in greenhouse cultivation in cold climates.This study aimed to assess the potential of passive techniques,namely black polyethylene mulch and row covers,for modifying RZT dynamics in lettuce(Lactuca sativa L.)production and to evaluate the predictive performance of the eXtreme Gradient Boosting(XGBoost)algorithm.Experiments were conducted in Iğdır,Türkiye,over a 61-day period,with soil temperature continuously monitored at depths of 1-30 cm under mulched and non-mulched conditions,alongside measurements of greenhouse air temperature both with and without row covers.The application of row covers increased internal air temperature by 5.8℃,while mulching raised RZT by 0.6-1.3℃,with effects diminishing at deeper layers.XGBoost modeling achieved high predictive accuracy,with RMSE values of 0.150-0.189◦C and R^(2)values above 0.99,and feature-importance analysis indicated that neighboring soil depths were the strongest predictors of RZT.These findings show that integrating row covers and mulching can stabilize the root-zone microclimate without active heating.The XGBoost model provides a robust tool for forecasting soil temperature and supports sustainable greenhouse production in cold regions. 展开更多
关键词 GREENHOUSE machine learning MULCH root zone temperature row cover
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Role of multicomponent nanoprecipitates on strength and low-temperature toughness of simulated heat-affected zone(HAZ)in high-strength low-carbon steel
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作者 Tingwei Yin Yongfeng Shen +2 位作者 Nan Jia Xin Sun Wenying Xue 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期579-594,共16页
This study investigates the microstructure and co-precipitation behavior of multicomponent(Ni(Al,Mn)and Cu)nanoparticles in the weld heat-affected zones of high-strength low-carbon steel.Through thermal simulations,th... This study investigates the microstructure and co-precipitation behavior of multicomponent(Ni(Al,Mn)and Cu)nanoparticles in the weld heat-affected zones of high-strength low-carbon steel.Through thermal simulations,the intercritical,fine-grained,and coarsegrained heat-affected zones were systematically characterized to elucidate the interplay between the microstructure,precipitation,and mechanical properties.At a heat input of 30 kJ·cm^(−1),Ni(Al,Mn)nanoparticles dissolve in the intercritical heat-affected zone,followed by dense reprecipitation coupled with significant coarsening of Cu particles during cooling,thereby retaining high strength but reducing impact toughness to(142±10)J(compared to(205±8)J of the base metal).The fine-grained heat-affected zone,under the same heat input,exhibits a refined ferritic-bainite matrix with a few fine Ni(Al,Mn)and slightly coarsened Cu particles,thus enhancing plastic deformation capacity and resulting in superior impact toughness of(196±7)J.Despite complete dissolution of original precipitates at peak temperatures in the coarse-grained heat-affected zone,re-precipitated nanoparticles provide effective strengthening effect,compensating for grain coarsening and dislocation recovery and resulting in an impressive impact toughness of(186±6)J.The toughening mechanism is primarily attributed to the synergistic actions of the matrix,precipitates,and deformation twins.These findings provide mechanistic and quantitative insights for developing processing-microstructure-property relationships in different welding heat-affected zones,and this framework can be further utilized to optimize welding parameters for tailored applications. 展开更多
关键词 high-strength low-carbon steel heat-affected zones multicomponent nanoparticles strengthening TOUGHENING
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Quantitative analysis of the relative tectonic activity of the Almus fault zone,Tokat,Türkiye
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作者 Serkan GÜRGÖZE 《Journal of Mountain Science》 2026年第1期29-48,共20页
The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents t... The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents the integration of morphometric indices to quantitatively assess the spatial variation of tectonic activity along the AFZ.The AFZ is an active fault with both strike-slip and normal fault components and consists of two main branches,Mercimekdağı-Çamdere Fault(MÇF)and Tokat Fault(TF)segments.This study aims to assess the relative tectonic activity of the AFZ using various morphometric indices,based on a 10 m resolution DEM,with the aid of ArcGIS and MATLAB software.For this purpose,morphometric indices such as hypsometric integral(HI:0.35-0.65),mountain front sinuosity(Smf:1.3-1.44),valley floor width-height ratio(Vf:0.15-2.28),asymmetry factor(AF:23-77),drainage basin shape(Bs:1.13-6.10)and normalized steepness index(ksn:1-498)were applied to 53 drainage basins.When the Smf and mean Vf indices results were evaluated,it was calculated that the uplift ratio of the region was more than 0.5 mm/yr.The spatial distribution of the relative tectonic activity(Iat)of the area was revealed by combining the obtained morphometric indices analysis results.According to the Iat result,it was concluded that the MercimekdağıÇamdere Fault and Tokat Fault segments have high tectonic activity,but the Mercimekdağı-Çamdere Fault segment has higher tectonic activity.The results obtained were also confirmed by field observations.This research provides valuable information for the evaluation of tectonic activity in drainage systems controlled by splay faults. 展开更多
关键词 Almus Fault zone Morphometric indices Relative tectonic activity Tokat Türkiye
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Mechanisms of the Creep-seismic Slip Transition along the Guanxian-Anxian Fault Zone,Longmen Shan:Evidence from the WFSD-3 Core
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作者 LAI Ya LI Haibing +5 位作者 SI Jialiang LI Chunrui WANG Huan ZHANG Lei SUN Zhiming ZHANG Jinjiang 《Acta Geologica Sinica(English Edition)》 2026年第1期231-250,共20页
The Guanxian-Anxian fault zone in the Longmen Shan,Sichuan,China,exhibits long-term creep-slip but ruptured during the 2008 Wenchuan earthquake,challenging the view that creeping faults rarely generate strong earthqua... The Guanxian-Anxian fault zone in the Longmen Shan,Sichuan,China,exhibits long-term creep-slip but ruptured during the 2008 Wenchuan earthquake,challenging the view that creeping faults rarely generate strong earthquakes.To investigate the transition from creep-slip to stick-slip,we analyzed fault rocks from the WFSD-3,using microstructural observations,XRD,μXRF,Raman spectroscopy,and quartz grain size statistics.Fault rocks show intense foliation,pressure-solution structures,and abundant clay minerals,reflecting long-term aseismic creep.At the interface between black and gray fault gouges at~1249.98 m,microstructures indicate stick-slip behavior,including truncated grains,angular fragments,and finer grain sizes.Here,clay content drops sharply while strong minerals(quartz,feldspar,calcite,dolomite)increase.Elemental mapping shows Al and K enriched in black gouge,whereas Ca and Si in gray gouge;Raman spectroscopy indicates possible graphitization;the finest quartz grains occur in black gouge.These features mark co-seismic principal slip zone of the Wenchuan earthquake.We propose that fluid-driven transformation of strong minerals into clays facilitates creep-slip,whereas localized precipitation of strong minerals strengthens the fault,causing stress accumulation and controlling the creep-slip to stick-slip transition.This mechanism has implications for reassessing seismic hazards of creeping faults. 展开更多
关键词 creep-slip STICK-SLIP fault rocks microstructure geochemistry Guanxian-Anxian fault zone Wenchuan earthquake Longmen Shan
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Experimental study on real-time monitoring of surrounding rock 3D wave velocity structure and failure zone in deep tunnels
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作者 Hongyun Yang Chuandong Jiang +4 位作者 Yong Li Zhi Lin Xiang Wang Yifei Wu Wanlin Feng 《International Journal of Mining Science and Technology》 2026年第2期423-437,共15页
An innovative real-time monitoring method for surrounding rock damage based on microseismic time-lapse double-difference tomography is proposed for delayed dynamic damage identification and insufficient detection of a... An innovative real-time monitoring method for surrounding rock damage based on microseismic time-lapse double-difference tomography is proposed for delayed dynamic damage identification and insufficient detection of adverse geological conditions in deep-buried tunnel construction.The installation techniques for microseismic sensors were optimized by mounting sensors at bolt ends which significantly improves signal-to-noise ratio(SNR)and anti-interference capability compared to conventional borehole placement.Subsequently,a 3D wave velocity evolution model that incorporates construction-induced disturbances was established,enabling the first visualization of spatiotemporal variations in surrounding rock wave velocity.It finds significant wave velocity reduction near the tunnel face,with roof and floor damage zones extending 40–50 m;wave velocities approaching undisturbed levels at 15 m ahead of the working face and on the laterally undisturbed side;pronounced spatial asymmetry in wave velocity distribution—values on the left side exceed those on the right,with a clear stress concentration or transition zone located 10–15 m;and systematically lower velocities behind the face than in front,indicating asymmetric rock damage development.These results provide essential theoretical support and practical guidance for optimizing dynamic construction strategies,enabling real-time adjustment of support parameters,and establishing safety early warning systems in deep-buried tunnel engineering. 展开更多
关键词 Deep-buried tunnel Microseismic monitoring Wave velocity tomography Surrounding rock damage zone Real-time monitoring
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Biodiversity and biogeographic patterns of Nereididae(Annelida)across the Indo-Pacific Convergence Zone
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作者 Jieyang WENG Xuwen WU +2 位作者 Tiantian WANG Chenrui LI Linlin ZHANG 《Journal of Oceanology and Limnology》 2026年第1期322-339,共18页
Nereididae is a prolific annelid family widely distributed in the world oceans,especially in the Indo-Pacific Convergence Zone(IPCZ).However,its biogeographic pattern remains unexplored in IPCZ.To contribute to the un... Nereididae is a prolific annelid family widely distributed in the world oceans,especially in the Indo-Pacific Convergence Zone(IPCZ).However,its biogeographic pattern remains unexplored in IPCZ.To contribute to the understanding of biodiversity and biogeography of Nereididae in the IPCZ,we integrated historical data of species distributions with those of model-predicted ones to determine the biogeographic patterns of nereid species,from which we projected to its future distribution patterns for 2090-2100 under different climate scenarios(SSP1-1.9 and SSP5-8.5).Functional diversity within IPCZ was assessed using functional richness,functional evenness,and functional disparity.Divergence times within Nereididae were estimated using three DNA marker genes(COI,16S,and 18S rRNA),and a time tree was constructed based on a strict molecular clock model.The IPCZ was established as a key Nereididae biodiversity hotspot through distribution modelling of 256 species(44 genera),and temperature emerging as the predominant climatic driver of species distribution patterns.The distribution of species and functional diversity is notable for its non-centralized pattern.We projected that by the end of the century,areas of medium-to-high species richness will expand significantly under the low-emission SSP1-1.9 climate scenario.However,under the high-emission SSP5-8.5 scenario,the suitability of these regions significantly declines,posing an increasingly severe threat to biodiversity.In addition,by molecular clock analysis,we revealed that the evolutionary divergence of extant nereidid species occurred mainly in the Cretaceous and Jurassic,suggesting that paleogeographical and environmental events,such as oceanic anoxic events,might have played a pivotal role in shaping the evolutionary trajectory and ecological adaptations of marine annelids.These findings highlight the importance of considering both current biodiversity patterns and historical contexts in conservation planning,and provided insights into the potential factors on the biogeographic distribution and evolutionary processes of Nereididae. 展开更多
关键词 NEREIDIDAE species distribution model(SDM) climate change BIODIVERSITY Indo-Pacific Convergence zone(IPCZ)
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A new algorithm for high-speed identificationof discontinuities on large-scale rock outcrop:A case study in Jinsha River suture zone
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作者 Jiali Han Jia Wang +6 位作者 Wenchuan Dong Shuonan Wang Qi Sun Tengyue Li Zhengxuan Xu Yingxu Zhang Wen Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1250-1265,共16页
Automatic identificationof discontinuities is a key focus in rock slope research.Conventional methods typically target small areas,which limits efficiencyand applicability for complex discontinuities in large-scale ro... Automatic identificationof discontinuities is a key focus in rock slope research.Conventional methods typically target small areas,which limits efficiencyand applicability for complex discontinuities in large-scale rock slopes.This study uses multi-angle unmanned aerial vehicle(UAV)nap-of-the-object photogrammetry to construct a high-definitionthree-dimensional(3D)point cloud model of the slope.The edge-firstconnection algorithm identifiesall edge points of discontinuities in the point cloud and completes recognition through simple connection analysis.This method avoids the complex calculations required for sequentially identifying discontinuity edges in conventional methods and achieves significantacceleration through algorithm optimization and parallel computation support.Based on this algorithm,the RockDiscontinuity Identification(RD ID)software is developed and applied to identify numerous highly disordered discontinuities on the Xulong slope in the Jinsha River suture zone.Processing tens of millions of point clouds within approximately 2 h demonstrates exceptional computational efficiency.The automatic algorithm accurately identifiesnearly 80%of planar discontinuities,with orientations and trace lengths closely matching manual results,highlighting its potential for large-scale rock outcrop applications.Comparisons with region growing algorithms further emphasize its effectiveness and accuracy.However,the algorithm struggles to identify linear discontinuities,which are a major source of error.Additionally,high roughness and smooth edges of discontinuities affect recognition accuracy,indicating areas for further improvement. 展开更多
关键词 Rock discontinuity Suture zone Automatic recognition Three-dimensional(3D)point cloud Unmanned aerial vehicle(UAV) PHOTOGRAMMETRY
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Subventricular zone radial glial cells maintain inhibitory neuron production in the human brain
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作者 Longzhong Jia 《四川生理科学杂志》 2026年第1期220-220,共1页
The number and diversity of inhibitory neurons(INs)increased substantially during mammalian brain evolution.However,the generative mechanisms of the vast repertoire of human INs remain elusive.We performed spatial and... The number and diversity of inhibitory neurons(INs)increased substantially during mammalian brain evolution.However,the generative mechanisms of the vast repertoire of human INs remain elusive.We performed spatial and single-cell transcriptomics of human medial ganglionic eminence(hMGE),a pivotal source of cortical and subpallial INs,and built the trajectories of hMGE-derived cells during brain development.We identified spatiotemporally and molecularly segregated progenitor cell populations fated to produce distinct IN types. 展开更多
关键词 radial glial cells subventricular zone human medial ganglionic eminence hmge inhibitory neurons ins increased inhibitory neurons medial ganglionic eminence human brain progenitor cell
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Dynamic Mechanisms of Land Use Conflict Under Main Function Oriented Zone Planning:A Case Study of Beijing-Tianjin-Hebei Region
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作者 ZHENG Yang CHENG Linlin +2 位作者 WANG Junqi WANG Yifang CUI Huizhen 《Chinese Geographical Science》 2026年第2期320-336,共17页
Systematically analyzing the impact mechanisms of policy on Land Use Conflict(LUC)is crucial for constructing effective conflict mitigation strategies.However,previous research on how policy influences LUC remains rel... Systematically analyzing the impact mechanisms of policy on Land Use Conflict(LUC)is crucial for constructing effective conflict mitigation strategies.However,previous research on how policy influences LUC remains relatively limited.Focusing on the indirect driving role of policy on LUC,this study proposed County Development Level(CDL)under Major Function Oriented Zone Planning(MFOZP)guidance as an intermediary variable,bridging the implicit influence of MFOZP and the explicit changes in LUC.Using the Beijing-Tianjin-Hebei(BTH)region in China as a case study,we analyzed the spatio-temporal evolution characteristics of LUC and CDL for the periods 2000-2010 and 2010-2020,before and after MFOZP implementation.Panel models and Geographically Weighted Regression(GWR)were employed to explore the mechanism by which CDL influences LUC under MFOZP guidance.The results show that:1)MFOZP implementation effectively alleviates land use pressure from regional development,with LUC continuously declining at a rate of 2.41%,while CDL exhibits slight growth(3.84%),during 2010-2020.2)Under MFOZP guidance,CDL reduces pressure on Land Use Structure Conflict(LUSC)and Land Use Process Conflict(LUPC),enhances its inhibitory effect on Land Use Function Conflict(LUFC),and significantly contributes to LUC coordination,with notable spatial heterogeneity.3)The coupling relationship between CDL and LUC has improved post-implementation.Based on this,tailored LUC coordination strategies are proposed for different functional zones.This study confirms the effectiveness of MFOZP in coordinating LUC and provides a scientific reference for LUC research under policy frameworks and the governance of LUC in the BTH region. 展开更多
关键词 Land Use Conflict(LUC) Major Function Oriented zone Planning(MFOZP) County Development Level(CDL) Beijing-Tianjin-Hebei(BTH)region China
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Spatial Pattern Evolution and Industrial Characteristics of Economic and Technological Development Zones and High-tech Industrial Zones in China 被引量:2
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作者 LI Jingxian LIU Qing LI Guicai 《Journal of Landscape Research》 2021年第2期11-16,共6页
Economic and technological development zone and high-tech industrial zone are important types of development zone in China,and there are differences in their connotation and goal setting.In this paper,basic data of na... Economic and technological development zone and high-tech industrial zone are important types of development zone in China,and there are differences in their connotation and goal setting.In this paper,basic data of national and provincial economic and technological development zones and high-tech industrial zones in China were collected and arranged.Kernel density analysis and other GIS spatial analysis techniques were used to analyze the evolution laws of spatial patterns of economic and technological development zones and high-tech industrial zones in cities from 2006 to 2018.First,the agglomeration intensity was compared by measuring the degree of regional agglomeration and dispersion on the two time nodes.Next,kernel density method was used to explore the evolution of the two in the spatial layout and location,and analyze development commonness and difference of economic and technological development zones and high-tech industrial zones.Finally,the trend and reason of spatial evolution of development zones with different leading industries were explored.Research results show that:①the agglomeration degree of layout of high-tech industrial zones is stronger than that of economic and technological development zones,and there are similarities and differences in distribution trend of spatial patterns of the two types of development zones;②the distribution of labor-intensive,capital-intensive and technology-intensive development zones is concentrated at smaller scales and dispersed at larger ones;③although there are differences between the economic and technological development zones and the high-tech industrial zones in the goal,support,structure and function,management system and so on,their spatial development presents a trend of convergence.In the future,when enhancing urban-rural planning and public administration,governments should combine the trend of industrial transformation and upgrading,and optimize spatial layout of development zones by adjusting industrial structure,layout,transportation and land use. 展开更多
关键词 Economic and technological development zone high-tech industrial zone Spatial pattern
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