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Mercury isotope geochemistry of the Aketashi VMS deposit:Constraints on ore-forming fluid sources
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作者 Ziru Jin Zhengwei Zhang +2 位作者 Chengquan Wu Jinhong Xu Xiyao Li 《Acta Geochimica》 2025年第6期1340-1351,共12页
This study investigates the mercury(Hg)isotope geochemistry of pyrite from the Aketashi volcanic hosted massive sulfide(VMS)deposit in the West Kunlun Orogenic Belt,China,aiming to elucidate the sources of ore-forming... This study investigates the mercury(Hg)isotope geochemistry of pyrite from the Aketashi volcanic hosted massive sulfide(VMS)deposit in the West Kunlun Orogenic Belt,China,aiming to elucidate the sources of ore-forming fluids and the behavior of Hg isotopes during mineralization.The Aketashi deposit is located within a Late Paleozoic back-arc basin,which is characterized by extensive Carboniferous magmatism and hydrothermal activity.Analysis of 19 pyrite ore samples revealed Hg isotope composition with δ^(202)Hg values ranging from−2.48‰to 0.87‰ and Δ^(199)Hg values from−0.02‰ to 0.40‰.The negative δ^(202)Hg values are indicative of isotopic fractionation resulting from hydrothermal processes,whereas the positive Δ^(199)Hg values imply a mixed fluid source comprising both magmatic and seawater-derived components.This study highlights the unique advantage of Hg isotopes in tracing multi-source fluid interactions(e.g.,magmatic vs.seawater-derived)in VMS systems,providing a novel methodology for global metallogenic studies.Our findings not only resolve the longstanding debate on fluid origins at Aketashi but also establish a framework for applying Hg isotopes to other VMS deposits worldwide. 展开更多
关键词 VMS deposits Hg isotopes West Kunlun ore-forming fluid sources
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Uniform regularity for the Navier-Stokes-Fourier system in T^(n)
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作者 FAN Ji-shan ZHOU Yong 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期501-508,共8页
In this paper,we prove the uniform regularity estimates for the Navier-Stokes-Fourier system in T^(n).
关键词 Navier-Stokes-Fourier regularity smooth solutions
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Regularity criteria of weak solutions to the 3D axisymmetric Navier-Stokes equations
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作者 ZHAO Ji-hong 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第4期773-784,共12页
We investigate a sufficient condition,in terms of the azimuthal componentω^(θ)ofω=curl u in cylindrical coordinates,for the regularity of axisymmetric weak solutions to the 3D incompressible Navier-Stokes equations... We investigate a sufficient condition,in terms of the azimuthal componentω^(θ)ofω=curl u in cylindrical coordinates,for the regularity of axisymmetric weak solutions to the 3D incompressible Navier-Stokes equations.More precisely,we prove that if■,then the weak solution u is actually a regular solution.Similar regularity criterion still holds in the homogeneous Triebel-Lizorkin spaces. 展开更多
关键词 Navier-Stokes equations axisymmetric weak solutions regularity criteria Besov spaces
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Distribution,types,metallogenic regularity and exploration potential analysis of zirconium deposit in China
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作者 Qiong-wen Liang Yong-shen Li +8 位作者 Ying-cai Sun De-gao Zhai Hai-rui Sun Shi-xu Zhou Bang-lu Zhang Xin Lü Jin-chi Xu Xue-feng Li Yi-lun Du 《China Geology》 2025年第2期408-430,共23页
Zirconium,prized for its exceptional corrosion resistance,high melting point,and unique nuclear properties,plays a critical role in multiple industrial sectors globally.Zirconium deposits are categorized into endogene... Zirconium,prized for its exceptional corrosion resistance,high melting point,and unique nuclear properties,plays a critical role in multiple industrial sectors globally.Zirconium deposits are categorized into endogenetic and exogenetic types in China.Endogenetic deposits-including alkaline rock-,alkaline granite-,and pegmatite-type mineralizations-predominantly occur along the Tarim Craton’s northern margin,the North China Craton,the southern Greater Khingan metallogenic belt,and the Yangtze Craton’s western margin.Exogenetic deposits,comprising clastic sedimentary,weathering crust,and fragmentation types,are concentrated in South China’s coastal zones.Endogenetic mineralization formed during Permian-Cretaceous magmatic-hydrothermal events linked to evolved alkaline granitic systems,while exogenetic deposits developed in Quaternary periods through weathering of zirconium-rich protoliths.However,economic extraction of endogenetic deposits remains constrained by rare earth element(REE)associations and radioactive complexities.Currently,China’s most economically significant reserves derive from clastic sedimentary systems,particularly coastal placer deposits.This study systematically synthesizes the spatial distribution and metallogenic mechanisms of Chinese zirconium deposits,offering strategic insights for resource exploration and sustainable utilization. 展开更多
关键词 Zirconium deposit Metallogenic regularity Critical mineral resources Prospecting potential Geological survey engineering
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C^(1,1) REGULARITY FOR SOLUTIONS TO THE DEGENERATE DUAL ORLICZ-MINKOWSKI PROBLEM
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作者 Di WU 《Acta Mathematica Scientia》 2025年第2期327-337,共11页
In this paper,C1,1 regularity for solutions to the degenerate dual Orlicz-Minkowski problem is considered.The dual Orlicz-Minkowski problem is a generalization of the Lp dual Minkowski problem in convex geometry.The p... In this paper,C1,1 regularity for solutions to the degenerate dual Orlicz-Minkowski problem is considered.The dual Orlicz-Minkowski problem is a generalization of the Lp dual Minkowski problem in convex geometry.The proof is adapted from Guan-Li[17]and Chen-Tu-Wu-Xiang[11]. 展开更多
关键词 C^(1 1)regularity Monge-Ampere type equation dual Orlicz-Minkowski problem
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Federated Multi-Label Feature Selection via Dual-Layer Hybrid Breeding Cooperative Particle Swarm Optimization with Manifold and Sparsity Regularization
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作者 Songsong Zhang Huazhong Jin +5 位作者 Zhiwei Ye Jia Yang Jixin Zhang Dongfang Wu Xiao Zheng Dingfeng Song 《Computers, Materials & Continua》 2026年第1期1141-1159,共19页
Multi-label feature selection(MFS)is a crucial dimensionality reduction technique aimed at identifying informative features associated with multiple labels.However,traditional centralized methods face significant chal... Multi-label feature selection(MFS)is a crucial dimensionality reduction technique aimed at identifying informative features associated with multiple labels.However,traditional centralized methods face significant challenges in privacy-sensitive and distributed settings,often neglecting label dependencies and suffering from low computational efficiency.To address these issues,we introduce a novel framework,Fed-MFSDHBCPSO—federated MFS via dual-layer hybrid breeding cooperative particle swarm optimization algorithm with manifold and sparsity regularization(DHBCPSO-MSR).Leveraging the federated learning paradigm,Fed-MFSDHBCPSO allows clients to perform local feature selection(FS)using DHBCPSO-MSR.Locally selected feature subsets are encrypted with differential privacy(DP)and transmitted to a central server,where they are securely aggregated and refined through secure multi-party computation(SMPC)until global convergence is achieved.Within each client,DHBCPSO-MSR employs a dual-layer FS strategy.The inner layer constructs sample and label similarity graphs,generates Laplacian matrices to capture the manifold structure between samples and labels,and applies L2,1-norm regularization to sparsify the feature subset,yielding an optimized feature weight matrix.The outer layer uses a hybrid breeding cooperative particle swarm optimization algorithm to further refine the feature weight matrix and identify the optimal feature subset.The updated weight matrix is then fed back to the inner layer for further optimization.Comprehensive experiments on multiple real-world multi-label datasets demonstrate that Fed-MFSDHBCPSO consistently outperforms both centralized and federated baseline methods across several key evaluation metrics. 展开更多
关键词 Multi-label feature selection federated learning manifold regularization sparse constraints hybrid breeding optimization algorithm particle swarm optimizatio algorithm privacy protection
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Occurrence Regularity and Control Research of Apple Early Defoliation Disease in West Sichuan Plateau 被引量:2
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作者 杨文渊 谢红江 +5 位作者 陈善波 江国良 陈栋 涂美艳 李靖 孙淑霞 《Plant Diseases and Pests》 CAS 2011年第5期25-27,68,共4页
[ Objective ] The research aimed to discuss the occurrence regularity of apple early defoliation disease and control effects of fungicides in west Sichuan plateau. [ Method ] Apple early defoliation disease in west Si... [ Objective ] The research aimed to discuss the occurrence regularity of apple early defoliation disease and control effects of fungicides in west Sichuan plateau. [ Method ] Apple early defoliation disease in west Sichuan plateau was systematically investigated during 2009 and 2011, and the control effects of different fungicides during different spraying periods were studied. [ Result] The species of pathogen mainly was Marssonina ma/i ( P. Henn), accounting for 32.5%, Phyl-losticta Pirina Sa accounted for 29.9%, and Alternaria mali Roberts accounted for 25.7%. The field fluctuation regularity was as follows : the disease generally be- gan in the mid-May and ended in early and middle October with only one damage peak during the whole year, the fluctuation had positive correlation with rainfall ( R2 =0.891 8 * * ). Control test showed that 40% flusilazole had the best control effect (86.5%), which was best to apply after anthesis. [ Conclusion ] The paper provided theoretical basis for the effective control against apple early defoliation disease. 展开更多
关键词 APPLE Early defoliation disease Occurrence regularity Control effect China
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Detection of an increase in EMG regularity during fatiguing contractions 被引量:2
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作者 陈伟婷 曹桂涛 王志中 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期541-545,共5页
The changes in the evolvement patterns of surface electromyography(EMG)signals during both static and dynamic fatiguing contractions are studied.The main finding is that the EMG signal tends to be more and more regu... The changes in the evolvement patterns of surface electromyography(EMG)signals during both static and dynamic fatiguing contractions are studied.The main finding is that the EMG signal tends to be more and more regular as muscle fatigues.An increase in the summation of all the regular evolvement patterns denoted by Dreg reflects such a tendency.Compared with traditional measurements,Dreg shows less variability among subjects when characterizing a fatigue process.In addition,the calculation of Dreg in the time domain is free from the restrictions disturbing those of spectral parameters.The detection of an increase in the EMG regularity not only proposes a new and easy way to inspect changes in EMG during the fatigue process,but also provides strong supports to estimate muscle fatigue by means of nonlinear analysis methods such as entropy and complexity measures.The detection method of signal regularity can also be applied to other physiological signals. 展开更多
关键词 muscle fatigue surface electromyography(EMG) regularity
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Factors affecting headway regularity on bus routes 被引量:5
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作者 张曼 李文权 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期99-102,共4页
The common phenomenon of uneven headway in bus service is explored based on the automatic vehicle location (AVL) data of Route 2 in Yichun City of Jiangxi province from 6:00 to 9:00 in the morning. The headway reg... The common phenomenon of uneven headway in bus service is explored based on the automatic vehicle location (AVL) data of Route 2 in Yichun City of Jiangxi province from 6:00 to 9:00 in the morning. The headway regularity of two stages 6: 00--7:00 and 7: 00--9:00 is comparatively analyzed, and it is found that both the traffic conditions and the passenger demand affect headway regularity. A bus arrival model, which assumes that the dwell time of a bus is linear in headway, is built to probe the effect of scheduled headway, and the model is simulated by Matlab. The simulation results reveal that the departure intervals and fluctuations affect headway regularity. Longer intervals and less fluctuation mean higher regularity of headway. And, the fluctuation has a more obvious influence on headway regularity than the interval. Controlling the fluctuations of scheduled headway can effectively raise the regularity of headway and improve the level of public transport service. 展开更多
关键词 traffic engineering bus scheduling headway regularity scheduled headway bus bunching
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Effects of Primary and Secondary Trunk Girdling on the Status and Distribution Regularity of Nutrients in Grape 被引量:1
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作者 张永福 王定康 +1 位作者 莫丽玲 董翠莲 《Agricultural Science & Technology》 CAS 2016年第12期2763-2768,共6页
Objective] The study aimed to investigate the effects of primary and sec-ondary trunk girdling on the status and distribution regularity of nutrients in grape. [Method] Using grape cultivar ‘Rose Honey’ as the exper... Objective] The study aimed to investigate the effects of primary and sec-ondary trunk girdling on the status and distribution regularity of nutrients in grape. [Method] Using grape cultivar ‘Rose Honey’ as the experimental material, the ef-fects of primary and secondary trunk girdling on carbon and nitrogen nutrition, min-eral nutrition and nutrient distribution regularity in leaves and branches above the girdling wound and roots below the girdling wound were analyzed. [Result] Girdling could significantly increase non-structural carbohydrate content (such as soluble sugar and starch) in branches above the girdling wound, reduce soluble protein and total nitrogen contents, and significantly improve C/N ratio. Specifical y, the highest C/N ratio in primary girdling group and secondary girdling group was 9.04 and 5.35, respectively, but C/N ratio in control group was only 4.89 in the same period. Girdling not only significantly decreased the content of non-structural carbohydrates (such as soluble sugar and starch) in roots, but also significantly declined soluble protein and total nitrogen content, which also reduced C/N ratio in various degrees. Specifical y, the lowest C/N ratio in primary girdling group and secondary girdling group was 1.16 and 3.06, respectively, while that in control group was 3.15 in the same period. ln addition, primary girdling exerted much greater effects on carbon and nitrogen nutrition than secondary girdling. Moreover, girdling significantly de-creased the contents of phosphorus, potassium, ferrum and copper in grape leaves, branches and roots. Specifical y, primary girdling exerted greater effects on ferrum and copper contents in leaves and branches. The contents of ferrum and copper in the first batch of samples exhibited significant differences between primary girdling group and control group: ferrum content in leaves was 75.05 μg/g DW in primary girdling group and that in control group was 85.29 μg/g DW; ferrum content in branches was 76.45 ?g/g DW in primary girdling group and copper content was 7.82 μg/g DW, while ferrum and copper contents in control group were 95.96 and 10.74 μg/g DW, respectively. [Conclusion] This study provided the basis for accu-rately regulating tree nutrition and ensuring safe and effective use of girdling tech-nique in ‘Rose Honey’ production. 展开更多
关键词 GRAPE GIRDLING Tree Nutrition Distribution regularity
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Study on the Occurrence and Epidemic Regularity and Region Division of Rice Blast in Nanchong City 被引量:1
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作者 彭昌家 白体坤 +2 位作者 丁攀 冯礼斌 杨宇衡 《Agricultural Science & Technology》 CAS 2016年第4期927-937,共11页
With the aim to improve the level of monitoring and warning as well as the comprehensive control of rice blast disease, and to feasibly reduce the disease threat in Nanchong City, the methods of GPS and GIS, systemati... With the aim to improve the level of monitoring and warning as well as the comprehensive control of rice blast disease, and to feasibly reduce the disease threat in Nanchong City, the methods of GPS and GIS, systematical monitoring and field survey, rice blast resistance identification, physiologic races of rice blast monitoring, and meteorological data analysis were performed to study the occurrence and epidemic region division, precise demarcation and occurrence and epidemic regularity of rice blast in Nanchong City. This study first completed the epidemic region division and precise demarcation; first clarified the initial affection(beginning period) locations, occurrence characteristics, epidemic trends and characteristics; explicated the existence of four epidemic peak periods of rice blast in the field, where the damage areas of first peak period played a decisive role during the blast epidemic years; in late May, the cumulative occurrence areas and annual occurrence areas presented higher positive correlation with the correlation coefficient of 0.817;and established a prediction model of occurrence areas per year based on the disease field rate at the end of boot stages and the diseased plant rate at dough stages. The results of investigation on the impact factors investigation of blast disease in Nanchong in recent years suggested that the internal causes were the decrease or loss of blast resistance of the rice cultivars, as well as the increase of physiological races with strong resistance to rice blast and the emergence of new virulent physiologic varieties; the external causes were suitable temperature, too much rainy, and sunlight shortage. Between 2010 and 2015, the short-term forecast accuracy for rice blast in Nanchong was up to 100%, and medium-and long-term forecast accuracy was also up to 98% and 95%, respectively, which increased by 5-15% than that before 1997, thereby making the control effect of rice blast in Nanchong increased by 15-30%. 展开更多
关键词 Rice Rice blast Region division Occurrence characteristics Epidemic regularity Early warning level
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Data-Path Placement Based on Regularity Extraction and Implementation
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作者 杨长旗 洪先龙 +2 位作者 蔡懿慈 经彤 吴为民 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第8期925-936,共12页
An algorithm named DPP is addressed.In it,a new model based on the concept of irregularity degree is founded to evaluate the regularity of cells.It generates the structure regularity of cells by exploiting the signal ... An algorithm named DPP is addressed.In it,a new model based on the concept of irregularity degree is founded to evaluate the regularity of cells.It generates the structure regularity of cells by exploiting the signal flow of circuit.Then,it converts the bit slice structure to parallel constraints to enable Q place algorithm.The design flow and the main algorithms are introduced.Finally,the satisfied experimental result of the tool compared with the Cadence placement tool SE is discussed. 展开更多
关键词 Data Path regularity extraction bit slice structure Q place
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PARTIAL REGULARITY FOR MINIMIZERS OF HIGHER ORDER QUASICONVEX FUNCTIONALS
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作者 吴在德 李君湘 梁汲廷 《Transactions of Tianjin University》 EI CAS 1997年第1期90-92,共3页
We consider the following quasiconvex functional I(u)=∫ Gf(x,δu,D mu) d x where u is a vector valued function in W m,p (G),m>1 and p>2. The partial C m,a —regularity is proved fo... We consider the following quasiconvex functional I(u)=∫ Gf(x,δu,D mu) d x where u is a vector valued function in W m,p (G),m>1 and p>2. The partial C m,a —regularity is proved for minimizers of I(u) under weaker conditions. 展开更多
关键词 higher order functional blow up technique partial regularity
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In, Sn, Pb and Zn Contents and Their Relationships in Ore-forming Fluids from Some In-rich and In-poor Deposits in China 被引量:16
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作者 ZHANG Qian ZHU Xiaoqing +1 位作者 HE Yuliang ZHU Zhaohui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第3期450-462,共13页
All the indium-rich deposits with indium contents in ores more than 100×10^-6 seems to be of cassiterite-sulfide deposits or Sn-bearing Pb-Zn deposits, e.g., in the Dachang Sn deposit in Guangxi, the Dulong Sn-Zn... All the indium-rich deposits with indium contents in ores more than 100×10^-6 seems to be of cassiterite-sulfide deposits or Sn-bearing Pb-Zn deposits, e.g., in the Dachang Sn deposit in Guangxi, the Dulong Sn-Zn deposit in Yunnan, and the Meng'entaolegai Ag-Pb-Zn deposit in Inner Mongolia, the indium contents in ores range from 98×10^-6 to 236×10^-6 and show a good positive correlation with contents of zinc and tin, and their correlation coefficients are 0.8781 and 0.7430, respectively. The indium contents from such Sn-poor deposits as the Fozichong Pb-Zn deposit in Guangxi and the Huanren Pb-Zn deposit in Liaoning are generally lower than 10×10^-6, i.e., whether tin is present or not in a deposit implies the enrichment extent of indium in ores. Whether the In enrichment itself in the ore -forming fluids or the ore-forming conditions has actually caused the enrichment/depletion of indium in the deposits? After studying the fluid inclusions in quartz crystallized at the main stage of mineralization of several In-rich and In-poor deposits in China, this paper analyzed the contents and studied the variation trend of In, Sn, Pb and Zn in the ore-forming fluids. The results show that the contents of lead and zinc in the ore-forming fluids of In-rich and -poor deposits are at the same level, and the lead contents range from 22×10^-6 to 81×10^-6 and zinc from 164×10^-6 to 309×10^-6, while the contents of indium and tin in the ore-forming fluids of In-rich deposits are far higher than those of Inpoor deposits, with a difference of 1-2 orders of magnitude. Indium and tin contents in ore-forming fluid of In-rich deposits are 1.9×10^-6-4.1×10^-6 and 7×10^-6-55×10^-6, and there is a very good positive correlation between the two elements, with a correlation coefficient of 0.9552. Indium and tin contents in ore-forming fluid of In-poor deposits are 0.03×10^-6-0.09×10^-6 and 0.4×10^-6-2.0×10^-6, respectively, and there is no apparent correlation between them. This indicates, on one hand, that In-rich oreforming fluids are the material basis for the formation of In-rich deposits, and, on the other hand, tin probably played a very important role in the transport and enrichment of indium. 展开更多
关键词 In-rich deposit In-poor deposit ore-forming fluid fluid inclusion ore-forming elements
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Differentiation regularity of urban-rural equalized development at prefecture-level city in China 被引量:55
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作者 LIU Yansui CHEN Cong LI Yurui 《Journal of Geographical Sciences》 SCIE CSCD 2015年第9期1075-1088,共14页
The urban-rural equalized development (URED) as a definite measure and operating model is beneficial to gradually eliminating the dual-track structure of urban-rural development, bridging the gap of urban-rural deve... The urban-rural equalized development (URED) as a definite measure and operating model is beneficial to gradually eliminating the dual-track structure of urban-rural development, bridging the gap of urban-rural development, and creating harmonious urban-rural interactions. This paper aims to explore the status quo of URED in China at prefecture level, and to reveal the spatio-temporal patterns of URED and its differentiation regularity. The results show that: (1) China's URED level can be categorized into two parts, i.e., the eastern and the western, according to the "HU Huanyong Line", presenting a pattern of "east high and west low" and the URED level improves on the whole with the increase of distance from the line; (2) China's URED level can also be categorized into the northern and the southern parts according to "Kunlun-Qinling-Huaihe Line", presenting a pattern of "north high and south low", and the URED level reduces on the whole with the increase of distance from the line; (3) At the national level, China's URED has a significant trend of spatial agglomeration, the high and low URED regions tend to be adjacent, namely, the URED level presents obvious regional unbalance; (4) The five sub-dimension indicators of the URED level in the geographical space also reveal similar regional differentiation pattern, and in the aspect of space a decreasing trend is found in the URED level from the eastern (northern coast, eastern coast and southern coast), the northeastern, the central (the middle reaches of the Yangtze River and the Yellow River) to the western (northwest and southwest); and (5) China's URED at prefecture-level city can be divided into five types of differentiation areas. This study contributes to promoting the integrative cognition of the status quo of China's URED and can serve as a scientific ref- erence concerning the decision-making of coordinating urban-rural development and of pushing forward new-type urbanization strategy in China. 展开更多
关键词 urban-rural equalized development urban-rural development transformation URBANIZATION rural disease differentiation regularity China
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LOCAL REGULARITY RESULT FOR SOLUTIONS OF OBSTACLE PROBLEMS 被引量:20
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作者 高红亚 田会英 《Acta Mathematica Scientia》 SCIE CSCD 2004年第1期71-74,共4页
This paper gives the local regularity result for solutions to obstacle problems of A-harmonic equation divA(x, ξu(x)) = 0, |A.(x,ξ)|≈|?|p-1, when 1 < p < n and the obstacle function (?)≥0.
关键词 Local regularity obstacle problem A-harmonic equation
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Rare Earth Elements Geochemistry of Laowan Gold Deposit in Henan Province: Trace to Source of Ore-Forming Materials 被引量:12
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作者 谢巧勤 徐晓春 +2 位作者 李晓萱 陈天虎 陆三明 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第1期115-120,共6页
The compositions of REE in quartz and pyrite from the main stage of the Laowan gold deposit in Henan Province and that in quartz from Laowan granite were determined by inductively coupled plasma-mass-spectrometry (IC... The compositions of REE in quartz and pyrite from the main stage of the Laowan gold deposit in Henan Province and that in quartz from Laowan granite were determined by inductively coupled plasma-mass-spectrometry (ICP-MS) to trace the source of ore-forming materials. Meanwhile, the REE compositions of the deposit ore, granite and metamorphic wall rock were also considered for comparative studies in detail. The range of ∑REE of quartz and pyrite from the deposit ores is 4.18 × 10^-6- 30.91 × 10^-6, the average of ∑REE is 13.39 × 10^-6, and the average of ∑REE of quartz in the Laowan granite is 6.68 × 10^-6. There is no distinct difference of REE parameters between the deposit ore quartz and granite quartz. The quartz in gold deposit has the same REE particular parameters as quartzes from Laowan granite, such as δEu, δCe, (La/Yb)N and (La/Sm)N, partition degree of LREE to HREE, especially, the chondrite-normalized REE patterns, but no similarity to those from metamorphic wall rock, which shows that ore-forming hydrothermal fluid is mainly the fluid coming from the Laowan granite magma, rather than metamorphic fluid. Meanwhile, comparison studies on REE features between minerals from the deposit ores and related geological bodies in the deposit show that REE characteristics of minerals can serve as an indicator of ore-forming fluid properties and sources, while the REE characteristics of the bulk samples (such as deposit ores, granites and wall rocks) can not trace the source of the ore-forming materials exactly. 展开更多
关键词 Laowan gold deposit REE geochemistry source of the ore-forming material ore-forming fluid rare earths
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REGULARITY OF WEAK SOLUTIONS TO MAGNETO-MICROPOLAR FLUID EQUATIONS 被引量:14
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作者 原保全 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1469-1480,共12页
In this article, we study the regularity of weak solutions and the blow-up criteria for smooth solutions to the magneto-micropolar fluid equations in R3. We obtain the classical blow-up criteria for smooth solutions ... In this article, we study the regularity of weak solutions and the blow-up criteria for smooth solutions to the magneto-micropolar fluid equations in R3. We obtain the classical blow-up criteria for smooth solutions (u,w, b), i.e., u ∈ Lq(0, T; LP(R3) for 2/q+3/P≤ 1with 3〈P≤∞,u∈C([0,T);L3(R3))or△u∈Lq(0,T,LP)for 3/2〈P≤∞ satisfying 2/q+3/P≤ 2. Moreover, our results indicate that the regularity of weak solutions is dominated by the velocity u of the fluid. In the end-point case p = ∞, the blow-up criteriacan be extended to more general spaces △u E L1 (0, T; B0∞,∞(R3). 展开更多
关键词 magneto-micropolar fluid equations regularity criteria blow-up criteria
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Distribution Characteristics and Metallogenic Regularity of Graphite Deposits in Qinling Orogen,China 被引量:8
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作者 FENG Yangwei QU Hongjun +1 位作者 YANG Chenyi LV Lushi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第4期1244-1263,共20页
Qinling orogen is one of the five main repository distribution provinces of large scale graphite resources. Graphite occurrence strata are multitudinous including NeoArchaean group to Neopaleozoic. Mineral deposit typ... Qinling orogen is one of the five main repository distribution provinces of large scale graphite resources. Graphite occurrence strata are multitudinous including NeoArchaean group to Neopaleozoic. Mineral deposit types are complete consisting of crystal flaky graphite deposit and aphanitic graphite deposit, ore types of the former are main graphite gneiss, graphite schist and graphitized marble, and ore types of the latter are main graphite layer metamorphosised from coal bed and graphitic carbargilite. At present, most graphite deposits with low research degree only implement preliminary investigations of the graphite resource, which has a good prospect. Based on the basic material of dozens of graphite deposits, spots and plays discovered in the Qinling orogen, this paper applied geologic multidisciplinary analysis method to disclose the graphite deposit types of the Qinling orogen, mainly through outdoors geologic survey and specimen examination with analysis of some typical deposits: regional metamorphism crystal graphite deposits and thermo-contact metamorphic aphanitic graphite deposits, with the control of latitudinally trending regional tectonic, graphite deposits of the Qinling orogen distribute sublatitudinally trending three large ore belts: I the Neoarchean-Proterozoic basement crystal graphite enrichment deposits zone along the south margin of North China plate; II the Carboniferous intermountain basin group aphanitic graphite enrichment deposits zone near the Shangdan suture of the West Qinling; III Paleozoic crystal graphite enrichment deposits zone in the Qinling paleomicroplate of the west part of the East Qinling.Conclusions are reached from multiple inquiries: Qinling multi-cycle complex continental collision orogen zone has experienced multiple tectonic framework transformation and polyphase tectonic thermal event from NeoArchean Erathem adjointing multiple graphite tectonic mineralization cycle. In the light of chief control of mineralization and ore types, each of the three large graphite deposits belts of the Qinling orogen has its own genesis: I graphite deposits enriched metallogenetic zone is that regional tectogenetic movement from NeoArchaean caused polyphase metapepsis, which superimposed up and reconstructed NeoArchean Erathem to Proterozoic basement, forming regional metamorphic big flake crystal graphite deposits; I! graphite deposits enriched metallogenetic zone is that polyphase regional tectogenetic movement associated with multiple heating caused by multiphase igneous intrusion, which resulted in original coal layers emerging multiple thermo-contact metamorphisms and formed thermo-contact metamorphic aphanitic graphite deposits. III graphite deposits enriched metallogenetic zone is that Palaeozoic cap- rock experienced polyphase metapepsis, forming regional metamorphic finely flake crystal graphite deposits. Cemprehensive research of metallogenetic mechanism in graphite deposits and its associated profitable deposits of the Qinling orogen is importance for future exploration. 展开更多
关键词 Qinling orogen graphite deposits graphite gneiss Metallogenic regularity
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Outline of Uranium Resources Characteristics and Metallogenetic Regularity in China 被引量:15
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作者 CAI Yuqi ZHANG Jindai +6 位作者 LI Ziying GUO Qingyin SONG Jiye FAN Honghai LIU Wusheng QI Fucheng ZHANG Minglin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第3期918-937,共20页
Uranium,as one of twenty-six kinds of important minerals in China,is strategic resource and energy mineral,which has been thoroughly investigated in the project of National Potential Evaluation of Uranium Resource.Dur... Uranium,as one of twenty-six kinds of important minerals in China,is strategic resource and energy mineral,which has been thoroughly investigated in the project of National Potential Evaluation of Uranium Resource.During the implementation of this project,the authors summarized the metallogenic regularity of uranium resource in China systematically,through the researches of geological characteristics of uranium resource,uranium deposits type(genetic and prediction type),temporal and spatial distribution,and metallogenic series.Based on the investigation of present situation and progress in uranium exploration,this paper proposes the uranium deposits in China should be divided into 4 classes,9 types,21 subtypes in genetic,and 50 types in prediction;suggests to divide China into 29 uranium metallogenic belts and 20 uranium prospective area,and constructs 20uranium-polymetallic metallogenic series,through summarizing temporal and spatial distribution characteristics and metallogenic regularity of uranium deposits in China.The above research is beneficial to the comprehensive understanding of regional uranium metallogenic regularity,and will direct the uranium exploration in the future. 展开更多
关键词 Uranium deposit uranium deposit type uranium metallogenic regularity uraniummetallogenic belt uranium metallogenic series
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