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The first power generation test of hot dry rock resources exploration and production demonstration project in the Gonghe Basin,Qinghai Province,China

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China Geology 2022年第3期5卷 372-382页

作者： Er-yong zhang Dong-guang Wen Gui-ling Wang Wei-de Yan Wen-shi Wang Cheng-ming Ye Xu-feng Li Huang Wang Xian-chun Tang Wei Weng Kuan Li Chong-yuan zhang Ming-xing Liang Hong-bao Luo Han-yue Hu Wei zhang Sen-qi zhang Xian-peng Jin Hai-dong Wu Lin-you zhang Qing-da Feng Jing-yu Xie Dan Wang Yun-chao He Yue-wei Wang Zu-bin Chen Zheng-pu Cheng Wei-feng Luo Yi Yang Hao zhang en-lai zha Yu-lie Gong Yu Zheng Chang-sheng Jiang Sheng-sheng zhang Xue Niu Hui zhang Li-sha Hu Gui-lin Zhu Wen-hao Xu zhao-xuan Niu Li Yang Center for Hydrogeology and environmental Geology Survey China Geological SurveyMinistry of Natural ResourcesBaoding 071051China Institute of Hydrogeology and environmental Geology Chinese Academy of Geological SciencesChina Geological SurveyShijiazhuang 050061China Department of Natural Resources of Qinghai Province Xining 810001China Institute of Exploration Techniques Chinese Academy of Geological SciencesChina Geological SurveyLangfang 065000China Department of Hydrogeology and environmental Geology China Geological SurveyMinistry of Natural ResourcesBeijing 100037China Chinese Academy of Geological Sciences China Geological SurveyBeijing 100037China Beijing Institute of Exploration engineering China Geological SurveyMinistry of Natural ResourcesBeijing 100083China Institute of Geomechanics Chinese Academy of Geological SciencesChina Geological SurveyBeijing 100081China Institute of Geophysical and Geochemical Exploration Chinese Academy of Geological SciencesChina Geological SurveyLangfang 065000China Institute of Exploration Technology Chinese Academy of Geological SciencesChina Geological SurveyChengdu 611734China Geoscience Documentation Center China Geological SurveyMinistry of Natural ResourcesBeijing 100083China Jilin University Changchun 130012China Oil and Gas Survey China Geological SurveyMinistry of Natural ResourcesBeijing 100083China Guangzhou Institute of energy Conversion Chinese Academy of SciencesGuangzhou 510640China Institute of Geophysics China Earthquake AdministrationBeijing 100081China Institute of the Hydrogeology and engineering Geology of Qinghai Xining 810008China

Hot dry rock(HDR)is a kind of clean energy with significant *** the 1970s,the United States,Japan,France,Australia,and other countries have attempted to conduct several HDR development research projects to extract thermal energy by breaking through key ***,up to now,the development of HDR is still in the research,development,and demonstration *** HDR exploration borehole(with 236℃ at a depth of 3705 m)was drilled into Triassic granite in the Gonghe Basin in northwest China in ***,China Geological Survey(CGS)launched the HDR resources exploration and production demonstration project in *** three years of efforts,a sequence of significant technological breakthroughs have been made,including the genetic model of deep heat sources,directional drilling and well completion in high-temperature hard rock,large-scale reservoir stimulation,reservoir characterization,and productivity evaluation,reservoir connectivity and flow circulation,efficient thermoelectric conversion,monitoring,and geological risk assessment,*** the whole-process technological system for HDR exploration and production has been preliminarily established *** first power generation test was completed in November *** results of this project will provide scientific support for HDR development and utilization in the future.

关键词： Hot dry rock Directional drilling Reservoir stimulation Microseismic monitoring Organic Rankine cycle(ORC) Power generation test energy geological survey engineering Gonghe Basin Qinghai Province China

The compound(E)-2-(3,4-dihydroxystyryl)-3-hydroxy-4H-pyran-4-one alleviates neuroinflammation and cognitive impairment in a mouse model of Alzheimer's disease

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Neural Regeneration Research 2025年第11期20卷 3330-3344页

作者： Xueyan Liu Wei Wu Xuejuan Li Chengyan Wang Ke Chai Fanru Yuan Huijuan Zheng Yuxing Yao Chenlu Li Zu-Cheng Ye Daijun zha Department of Medicinal Chemistry School of PharmacyFujian Medical UniversityFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Institute of Laboratory Animal Center Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Neurosurgery Neurosurgery Research InstituteThe First Affiliated HospitalFujian Medical UniversityFuzhouFujian ProvinceChina Department of Hyperbaric Oxygen National Regional Medical CenterBinhai Campus of the First Affiliated HospitalFujian Medical UniversityFuzhouFujian ProvinceChina

Previous studies have shown that the compound(E)-2-(3,4-dihydroxystyryl)-3-hydroxy-4H-pyran-4-one(D30),a pyromeconic acid derivative,possesses antioxidant and anti-inflammatory properties,inhibits amyloid-β aggregation,and alleviates scopolamine-induced cognitive impairment,similar to the phase Ⅲ clinical drug *** this study,we established a mouse model of Alzheimer's disease via intracerebroventricular injection of fibrillar amyloid-β to investigate the effect of D30 on fibrillar amyloid-β-induced *** results showed that D30 alleviated fibrillar amyloid-β-induced cognitive impairment,promoted fibrillar amyloid-β clearance from the hippocampus and cortex,suppressed oxidative stress,and inhibited activation of microglia and astrocytes.D30 also reversed the fibrillar amyloid-β-induced loss of dendritic spines and synaptic protein ***,we demonstrated that exogenous fibrillar amyloid-βintroduced by intracerebroventricular injection greatly increased galectin-3 expression levels in the brain,and this increase was blocked by *** the role of D30 in clearing amyloid-β,inhibiting neuroinflammation,protecting synapses,and improving cognition,this study highlights the potential of galectin-3 as a promising treatment target for patients with Alzheimer's disease.

关键词： Alzheimer's disease amyloid-β astrocyte cognitive impairment D30 dendritic spines galectin-3 microglia neuroinflammation neuron

Chemo-selective control of Ritter-type reaction by coordinatively unsaturated inorganic salt hydrates

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Organic Chemistry Frontiers 2022年第6期9卷 1541-1549页

作者： Huifang lai Jiexin Xu Jin Lin Biling Su Daijun zha Department of Medicinal Chemistry School of PharmacyFujian Medical UniversityFuzhou 350004Fujian ProvinceChina Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research Fujian Medical UniversityChina

The Ritter-type reaction, without relying on a pre-installed functional group, is a highly efficient tool forthe construction of amides. However, the intrinsic chemo-selectivity that determines the generation ofamides or byproducts limits the efficiency and yield of the reaction. From 68 different types of hydrates,we found that a coordinatively unsaturated inorganic salt hydrate, MgSO_(4)·2H_(2)O, controlled chemoselectivity and eliminated the shortcomings of other synthesis approaches. To rationalize the differencesin selectivity of inorganic salt hydrates, we analyzed their corresponding water content, alkalinity, anions,and cations. MgSO_(4)·2H_(2)O was used with diverse scaffolds and C–H oxygenations, which demonstratedits generality in synthetic utility. Because it is readily available and it significantly improves yield, we expectthat MgSO_(4)·2H_(2)O will have broad application for Ritter-type reactions.

关键词： inorganic hydrate unsaturated

Multi-dimensional controllability analysis of precision ball bearing integrity

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Advances in Manufacturing 2023年第4期11卷 682-693页

作者： lai Hu Jun zha Wei-Hua zhao Xiao-Fei Peng Yao-Long Chen School of Mechanical engineering Xi’an Jiaotong UniversityXi’an710049People’s Republic of China State Key Laboratory for Manufacturing Systems engineering Xi’an Jiaotong UniversityXi’an710054People’s Republic of China Luoyang Bearing Science and Technology Co. Ltd.Luoyang471039HenanPeople’s Republic of China

Many factors affect the integrity of precision ball *** this study,the multi-dimensional controllability of precision ball bearings produced in different company brands(bearing A and bearing B)were studied and *** geometric errors(flatness,parallelism,roundness and cylindricity of inner and outer rings,roundness,groove and roughness of inner and outer rings)and vibration errors of bearings were ***,the residual stress,residual austenite content,element content ratio,metamorphic layer and temperature-vibration displacement coupling test were also *** on the above analysis conclusion,the bearing fatigue life test was carried out for 2150 *** reliability of the conclusion is proved again as *** the residual austenite content in the raceway of precision ball bearing is 10%,the axial residual stress is 877.4 MPa;the tangential residual stress is 488.1 MPa;the carbon content is 6%;the test temperature of bearing is the lowest;and the service life is prolonged.

关键词： Precision ball bearing Controllability Geometric errors Carbon content Residual austenite Residual stress

晋西黄土区不同植被恢复阶段土壤生态化学计量特征

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水土保持研究 2025年第1期32卷 30-38+47页

作者：高连炜张红丽查同刚北京林业大学水土保持学院水利部水土保持监测中心

[目的]开展土壤生态化学计量特征随植被恢复进程的变化研究，探究植被恢复引起土壤养分变化规律及其作用机制，对认识植被恢复与土壤养分的关系，指导植被恢复实践具有重要意义。[方法]以晋西黄土区不同植被恢复阶段(撂荒地、草地、灌... 详细信息

[目的]开展土壤生态化学计量特征随植被恢复进程的变化研究，探究植被恢复引起土壤养分变化规律及其作用机制，对认识植被恢复与土壤养分的关系，指导植被恢复实践具有重要意义。[方法]以晋西黄土区不同植被恢复阶段(撂荒地、草地、灌木林、先锋阔叶林、针叶林)的5种林(草)地为研究对象，通过调查采样和室内分析，探究土壤生态化学计量特征随植被恢复的进程变化及其影响因素。[结果](1)随着植被的恢复，先锋阔叶林和针叶林阶段的SOC含量较上一阶段增加19.8%,土壤TN含量较上一阶段增加17.6%,而土壤TP含量较上一阶段减少12.4%;(2)随着植被恢复的发展，土壤C∶P和N∶P显著增加，C∶N的变化无明显规律，在先锋阔叶林和针叶林阶段的土壤C∶P较上一阶段增加26.6%;先锋阔叶林和针叶林阶段在0—40 cm土层的土壤N∶P较上一阶段增加40.2%,40—100 cm土层的土壤N∶P较上一阶段增加35.7%;土壤C∶N在不同植被恢复阶段间的变化未见明显规律，研究区土壤逐渐由C,N的限制转变为P的限制；(3)各植被恢复阶段土壤C∶P和N∶P主要与砂粒含量呈显著负相关，与孔隙度呈显著正相关，土壤C∶N与其他因子的相关性不明显。[结论]植被恢复有利于土壤C,N含量增加，改善土壤理化性质，在植被恢复过程应同时注重P元素的调控，以提高晋西黄土区植被生态恢复水平。

关键词：植被恢复土壤养分生态化学计量特征

Ore-Forming Fluids Characteristics and Metallogenesis of the Anjing Hitam Pb-Zn Deposit in Northern Sumatra, Indonesia

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Journal of Earth Science 2019年第1期30卷 131-141页

作者： Chaowen Huang Gaofeng Du Huajun Jiang Jianfeng Xie Daohan zha Huan Li Chun-Kit lai Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological environment Monitoring Ministry of Education School of Geosciences and Info-Physics Central South University Geological Survey of Anhui Province School of Earth and Space Sciences University of Science and Technology of China Research Institute of Hunan Provincial Nonfenous Metals Geological Exploration Bureau Hunan Key Laboratory of Land Resources Evaluation and Utilization Faculty of Science Universiti Brunei Darussalam Centre of Excellence in Ore Deposits(CODES) University of Tasmania

The Anjing Hitam Pb-Zn deposit in northern Sumatra(Indonesia) is one of the largest Pb-Zn deposits in the region. The stratiform orebodies are mainly hosted in the middle member of the Carboniferous–Permian Kluet Formation of the Tapanuli Group. Mineral paragenesis and crosscutting relationships suggest a two-stage Pb-Zn mineralization:(I) sedimentary and(Ⅱ) hydrothermal mineralization. Ore-related calcite from both stages Ⅰ and Ⅱ contains mainly liquid-and gas-liquid two-phase-type fluid inclusions(FI). For stage I ore-forming fluids, FI homogenization temperatures(T_h) are 105 to 199 oC, and the salinities are 9.6 wt.% to 16.6 wt.% NaCleqiv, reflecting low temperature and medium-low salinity; whereas in stage Ⅱ, the T_h(206 to 267 oC) and salinity(19.0 wt.% to 22.5 wt.% NaCleqiv) are considerably higher. Fluid inclusion and C-O isotope characteristics suggest that the stage I ore-forming fluids were mainly derived from a mixture of seawater and magmatic fluids(probably from deep-lying plutons), whereas the stage Ⅱ ore-forming fluids were likely magmatic-derived with wall rock input. We propose that the Anjing Hitam deposit was a Carboniferous exhalative sedimentary(SEDEX) deposit overprinted by the Pleistocene vein-style magmatic-hydrothermal mineralization.

关键词： Anjing Hitam SEDEX, C-O isotopes fluid inclusion Sumatra Indonesia

HOMOMORPHISMS BETWEen CHEVALLEY GROUPS OF TYPES C_nAND G_2 OVER FINITE FIELDS

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Chinese Annals of Mathematics,Series B 1997年第2期18卷 167-172页

作者： zha JIANGUO Department of Applied Mathematics Tongji UniversityShanghai 200092China

It is known that there exists an isogeny sort of Chevalley groups G (Σ, F) associated to any indecomposable root system Σ and any field F . In this paper the author determines all nontrivial homomorphisms from G(Σ, k) to G(Σ, K) when the root system Σ is of type C n or G 2 , and the fields k and K are finite fields of characteristic p .

关键词： Chevalley group Homomorphism Finite field

Geometric Error Identification of Gantry-Type CNC Machine Tool Based on Multi-Station Synchronization Laser Tracers

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Chinese Journal of Mechanical engineering 2024年第2期37卷 150-162页

作者： Jun zha Huijie zhang School of Mechanical engineering Xi’an Jiaotong UniversityXi’an 710049China Xi’an Jiaotong University Suzhou Academy Suzhou 215123China

Laser tracers are a three-dimensional coordinate measurement system that are widely used in industrial *** propose a geometric error identification method based on multi-station synchronization laser tracers to enable the rapid and high-precision measurement of geometric errors for gantry-type computer numerical control(CNC)machine *** method also improves on the existing measurement efficiency issues in the single-base station measurement method and multi-base station time-sharing measurement *** consider a three-axis gantry-type CNC machine tool,and the geometric error mathematical model is derived and established based on the combination of screw theory and a topological analysis of the machine kinematic *** four-station laser tracers position and measurement points are realized based on the multi-point positioning principle.A self-calibration algorithm is proposed for the coordinate calibration process of a laser tracer using the Levenberg-Marquardt nonlinear least squares method,and the geometric error is solved using Taylor’s first-order linearization *** experimental results show that the geometric error calculated based on this modeling method is comparable to the results from the Etalon laser *** a volume of 800 mm×1000 mm×350 mm,the maximum differences of the linear,angular,and spatial position errors were 2.0μm,2.7μrad,and 12.0μm,respectively,which verifies the accuracy of the proposed *** research proposes a modeling method for the precise measurement of errors in machine tools,and the applied nature of this study also makes it relevant both to researchers and those in the industrial sector.

关键词： Multi-point positioning Multi-station synchronization CNC machine tool Geometric error Error separation

Adaptive learning algorithm based on mixture Gaussian background

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Journal of Systems engineering and Electronics 2007年第2期18卷 369-376页

作者： zha Yufei Bi Duyan Signal and Information Processing Lab Engineering Coll. of Air Force Engineering Univ. Xi'an 710038 P. R. China

The key problem of the adaptive mixture background model is that the parameters can adaptively change according to the input data. To address the problem, a new method is proposed. Firstly, the recursive equations are inferred based on the maximum likelihood rule. Secondly, the forgetting factor and learning rate factor are redefined, and their still more general formulations are obtained by analyzing their practical functions. Lastly, the convergence of the proposed algorithm is proved to enable the estimation converge to a local maximum of the data likelihood function according to the stochastic approximation theory. The experiments show that the proposed learning algorithm excels the formers both in converging rate and accuracy.

关键词： Mixture Gaussian model Background model, Learning algorithm.