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Journal of Earth Science 2024年第4期35卷 1186-1195页

作者： Yangyang Zhang Yuelong Chen Dapeng Li huan kang Mingliang Fang Yunliang Xu School of Earth Science and Resources China University of GeosciencesBeijing100083China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing100083China Jinchuan Group Company Limited Jinchang737104China China-Explo Tian Cheng(Beijing)Technology Company Limited Beijing100093China

Radon(Rn)and helium(He)gases from uranium decay form distinct anomalies related to buried uranium *** order to trace the geochemical anomalous sources from the volcanic-related uranium deposits in deeply buried areas,systematical Rn contents and He isotope ratios were analyzed from the Daguanchang uranium *** soil gas Rn concentrations above the deep uranium are ten times higher than those in barren areas,indicating that instantaneous Rn content measurements can be used to detect deeply buried *** helium isotope ratios(^(3)He/^(4)He)of the unmineralized samples from the mineralized drill hole(ZK1)are relatively lower and uniform compared to those of the samples from no-mineral drill hole(ZK2).However,the Th and U contents of the drill core samples from ZK1 are slightly lower than those of the samples from ZK2,indicating that the lower 3He/4He ratios in ZK1 are most likely due to the addition of 4He from underlying uranium *** differences in the instantaneous Rn contents are consistent with the variations in the He isotope ratios of the drill core *** results demonstrate that soil gas Rn and ^(3)He/^(4)He ratios are useful tracers and can indicate the existence of deeply buried volcanic-related hydrothermal uranium ores.

关键词： tracers radon helium ^(3)He/^(4)He ratio uranium deposits Daguanchang deposit

Student Academic Performance Predictive Model Based on Dual-stream Deep Network

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计算机科学 2024年第10期51卷 119-128页

作者： XIE Hui ZHANG Pengyuan DONG Zexiao YANG Huiting kang huan HE Jiangshan CHEN Xueli Center for Biomedical-photonics and Molecular Imaging Xi’an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life InformationSchool of Life Science and TechnologyXidian UniversityXi’an 710126China Engineering Research Center of Molecular and Neuro Imaging Ministry of EducationXi’an 710126China Innovation Center for Advanced Medical Imaging and Intelligent Medicine Guangzhou Institute of TechnologyXidian UniversityGuangzhou 510550China

Blended teaching is one of the essential teaching methods with the development of information *** a learning effect evaluation model is helpful to improve students’academic performance and helps teachers to better implement course ***,a lack of evaluation models for the fusion of temporal and non-temporal behavioral data leads to an unsatisfactory evaluation *** meet the demand for predicting students’academic performance through learning behavior data,this study proposes a learning effect evaluation method that integrates expert perspective indicators to predict academic performance by constructing a dual-stream network that combines temporal behavior data and non-temporal behavior data in the learning *** this paper,firstly,the Delphi method is used to analyze and process the course learning behavior data of students and establish an effective evaluation index system of learning behavior with universality;secondly,the Mann-Whitney U-test and the complex correlation analysis are used to analyze further and validate the evaluation indexes;and lastly,a dual-stream information fusion model,which combines temporal and non-temporal features,is *** learning effect evaluation model is built,and the results of the mean absolute error(MAE)and root mean square error(RMSE)indexes are 4.16 and 5.29,*** study indicates that combining expert perspectives for evaluation index selection and further fusing temporal and non-temporal behavioral features that for learning effect evaluation and prediction is rationality,accuracy,and effectiveness,which provides a powerful help for the practical application of learning effect evaluation and prediction.

关键词： Blended teaching Expert perspective indicators Two-stream information fusion model

共和盆地河流碎屑锆石U-Pb年龄特征、Hf同位素组成及其对构造和地壳演化的启示

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地质通报 2024年第6期43卷 1004-1020页

作者：艾尼卡尔·艾克帕尔陈岳龙梁乾坤康欢中国地质大学(北京)地球科学与资源学院北京100083 中国地震局地质研究所地震动力学国家重点实验室北京100029

为揭示青海共和盆地沉积源区构造活动和地壳演化历史,应用LA-MC-ICP-MS技术,对共和盆地曲什安河与西河河漫滩沉积物中的碎屑锆石进行了U-Pb定年和Hf同位素分析。得出碎屑锆石U-Pb年龄可分为5组:309~172 Ma、471~368 Ma、943~737 Ma、236... 详细信息

为揭示青海共和盆地沉积源区构造活动和地壳演化历史,应用LA-MC-ICP-MS技术,对共和盆地曲什安河与西河河漫滩沉积物中的碎屑锆石进行了U-Pb定年和Hf同位素分析。得出碎屑锆石U-Pb年龄可分为5组:309~172 Ma、471~368 Ma、943~737 Ma、2368~1698 Ma、2543~2453 Ma。结合研究区构造-岩浆事件得出,曲什安河与西河河漫滩碎屑沉积物是西秦岭地块在不同时期提供的结果。碎屑锆石U-Pb年龄存在2个主要峰值,约236 Ma和约403 Ma,反映了古特提斯洋和原特提斯洋在不同部分的俯冲导致陆块碰撞,形成强烈岩浆事件的地质记录,碰撞后伸展阶段出现裂谷和新生洋盆。Hf同位素组成特征揭示,源区地壳在2.7~1.3 Ga经历了主要增生期,形成现今地壳的84%。ε_(Hf)(t)值为-14.7~+15.0,Hf亏损模式年龄在3.6~0.24Ga范围内,表明源区基底存在古太古代古老地壳物质。约0.5 Ga以来,地壳增长以古老地壳物质再循环为主,并在0.28 Ga左右地壳停止了生长。依据前人公式计算了曲什安河与西河河漫滩碎屑沉积物物源区各时期的重熔/增生比例。

关键词：共和盆地碎屑锆石 U-Pb年龄 Lu-Hf同位素大陆地壳生长

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经鼻高流量湿化氧疗在重症肺部感染合并呼吸衰竭患者脱机后的应用

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中国医学创新 2024年第18期21卷 18-22页

作者：康欢曾期龙刘伟广东省人民医院赣州医院(赣州市立医院)重症医学科江西赣州341000

目的:探究经鼻高流量湿化氧疗(HFNC)在重症肺部感染合并呼吸衰竭患者脱机后的应用。方法:拟选取2022年9月—2023年5月广东省人民医院赣州医院(赣州市立医院)收治的重症肺部感染合并呼吸衰竭患者90例为研究对象,经随机数字表法,分为对照... 详细信息

目的:探究经鼻高流量湿化氧疗(HFNC)在重症肺部感染合并呼吸衰竭患者脱机后的应用。方法:拟选取2022年9月—2023年5月广东省人民医院赣州医院(赣州市立医院)收治的重症肺部感染合并呼吸衰竭患者90例为研究对象,经随机数字表法,分为对照组与观察组,各45例。所有患者均满足脱机标准,对照组脱机后予以常规氧疗,观察组脱机后给予HFNC。比较两组脱机成功率及成功脱机24、48、96 h及1周后的再插管率,以及血清中Th1、Th2细胞因子[肿瘤坏死因子-α(TNF-α)和白细胞介素(IL)-6]水平,观察脱机后12、24 h的血气分析[动脉血氧分压(PaO_(2))、动脉血二氧化碳分压(PaCO_(2))、动脉血氧饱和度(SaO_(2))],并统计两组氧疗24 h内低血氧症发生率和氧疗1周内并发症发生情况。结果:观察组脱机后12、24 h的PaO_(2)、SaO_(2)均高于对照组,脱机后24 h的PaCO_(2)低于对照组(P0.05)。两组成功脱机24 h后再插管率比较,差异无统计学意义(P>0.05);观察组成功脱机48、96 h及1周后的再插管率均显著低于对照组(P<0.05)。观察组氧疗24 h内低血氧症发生率和氧疗1周内其他并发症发生率均低于对照组(P<0.05)。治疗后,两组TNF-α、IL-6水平均下降,且观察组均低于对照组(P<0.05)。结论:HFNC可有效改善重症肺部感染合并呼吸衰竭患者脱机后的血气指标,有效调节Th1、Th2细胞因子,减轻肺部炎症,改善呼吸功能,提高脱机成功率,降低并发症发生率及再插管率。

关键词：高流量湿化氧疗重症肺部感染呼吸衰竭细胞因子

Application of Optically Stimulated Luminescence Technique in Exploring a Concealed Sandstone-type Uranium Deposit

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Acta Geologica Sinica(English Edition) 2022年第2期96卷 571-581页

作者： kang huan CHEN Yuelong XUE Guoliang ZHAO Junxiang ZHANG Na ZHANG Yangyang State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China Key Laboratory of Crustal Dynamics Institute of Crustal DynamicsChina Earthquake AdministrationBeijing 100085China

Identifying ore-induced geochemical anomalies at the surface that indicate concealed deposits in buried areas remains a significant challenge in geochemical exploration. In this study, in order to trace the source of the geochemical anomalies, systematic luminescence intensity analyses were conducted on quartz grains from the Quaternary regolith at the Hadatu sandstone-type uranium deposit in the Erenhot Basin. The optically stimulated luminescence(OSL) ages were much older than the depositional ages of the Quaternary regolith. Moreover, quartz OSL ages were closely related to both borehole grades and sampling depths. Thus, the abnormal mineral OSL ages from near-surface sediments were ultimately controlled by the sandstone-type uranium deposits. This is identical to the rapid changes of quartz OSL ages(0.063 ka/cm) and equivalent doses(0.19 Gy/cm) with depths in a given sampling site. The instantaneous soil radon concentration was positively correlated with the quartz OSL apparent age, indicating their ore-induced origin and, as a result, their effectiveness in the exploration of concealed uranium deposits. Other parameters, including mobile-state uranium and;Po contents, were poorly correlated with quartz OSL ages and therefore should only be used with caution for geochemical exploration. This is the first time an attempt has been made to discriminate the ore-induced sources for different surface anomaly parameters, including instantaneous soil radon, mobile-state uranium and;Po contents for concealed sandstonetype uranium deposits.

关键词： OSL dating geochemical anomaly ore-induced anomaly concealed sandstone-type uranium deposit

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豚鼠气单胞菌研究进展

动物医学进展 2024年第6期45卷 106-110页

作者：袁中华宋海超刘俊彤康元环孙武文单晓枫吉林农业大学动物科学技术学院吉林长春130118

豚鼠气单胞菌属于气单胞菌属,在自然界中通过食物和水广泛传播,是人、动物和水生生物共患的条件性病原菌,严重危害人类身体健康,同时是造成多种淡水鱼疾病的主要原因,给水产养殖业造成了巨大的威胁。目前,对豚鼠气单胞菌发展的研究,学... 详细信息

豚鼠气单胞菌属于气单胞菌属,在自然界中通过食物和水广泛传播,是人、动物和水生生物共患的条件性病原菌,严重危害人类身体健康,同时是造成多种淡水鱼疾病的主要原因,给水产养殖业造成了巨大的威胁。目前,对豚鼠气单胞菌发展的研究,学界很少从系统去概述,论文从豚鼠气单胞菌的病原学、临床特征、流行现状、致病机理及防治等几个方面的最新研究进展进行概述,旨在为其防治及研究提供参考。

关键词：豚鼠气单胞菌流行病学临床特征致病机理防治

Unidirectional transport of both wettable and nonwettable liquids on an asymmetrically concave structured surface

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Fundamental Research 2024年第3期4卷 557-562页

作者： Zhongxue Tang kang Luan Bojie Xu huan Liu Research Institute for Frontier Science School of PhysicsBeihang UniversityBeijing 100191China Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityHaidian DistrictBeijing 100191China

Unidirectional liquid transport(UDLT)has been widely used in various fields as an important process for transferring both mass and ***,UDLT driven by a structural gradient has been witnessed for a long time only in wettable *** nonwettable liquids,UDLT can hardly proceed merely by a structural ***,we propose an asymmetrically concave structured surface(AMC-surface),featuring tip-to-base periodically arranged pyramid-shaped concave structures with a certain degree of overlap,which enables the UDLT of both wettable and nonwettable *** wettable liquids,the capillary force along each corner leads to the UDLT pointing toward the base side of the concave pyramid,while for nonwettable liquids,the UDLT is attributable to the static liquid pressure overwhelming the repulsive Laplace pressure induced by the asymmetric grooves and overlapping *** a result,both wettable and nonwettable liquids transport spontaneously and unidirectionally on the AMC-surface with no energy ***,the concave structure endows good mechanical stability and can be easily prepared using a facile nail-punching approach over a large *** also demonstrated its application in a continuous chemical reaction in a confined *** envision that the unique UDLT behavior on the as-developed AMC-surface will shed new light on the programmable manipulation of various liquids.

关键词： Unidirectional liquidtransport Asymmetrically concave structure Capillary force Laplace pressure Wettability

An Improved MPH-Based Delay-constrained Steiner Tree Algorithm

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Communications and Network 2011年第3期3卷 127-132页

作者： Chun-De Yang kang huan College of Mathematics and Physics Chongqing University of Posts and Telecommunication College of Computer Science and Technology Chongqing University of Posts and Telecommunication

In order to optimize cost and decrease complexity with a delay upper bound, the delay-constrained Steiner tree problem is addressed. Base on the new delay-constrained MPH (DCMPH_1) algorithm and through improving on the select path, an improved MPH-based delay-constrained Steiner tree algorithm is presented in this paper. With the new algorithm a destination node can join the existing multicast tree by selecting the path whose cost is the least;if the path’s delay destroys the delay upper bound, the least-cost path which meets the delay upper bound can be constructed through the least-cost path, and then is used to take the place of the least-cost path to join the current multicast tree. By the way, a low-cost multicast spanning tree can be constructed and the delay upper bound isn’t destroyed. Experimental results through simulations show that the new algorithm is superior to DCMPH_1 algorithm in the performance of spanning tree and the space complexity.

关键词： Multicast Tree Delay-Constrained Steiner Tree

Durable hierarchical phosphorus‐doped biphase MoS_(2)electrocatalysts with enhanced H^(*)adsorption

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Carbon Energy 2024年第4期6卷 104-114页

作者： Yongteng Qian Jianmin Yu Zhiyi Lyu Qianwen Zhang Tae Hyeong Lee huan Pang Dae Joon kang College of Pharmacy Jinhua PolytechnicJinhuaZhejiangChina Department of Physics Sungkyunkwan UniversitySuwonGyeonggi‐doRepublic of Korea International Collaborative Laboratory of 2D Materials for Optoelectronic Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhenGuangdongChina School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhouJiangsuChina

Phase engineering is an efficient strategy for enhancing the kinetics of electrocatalytic ***,phase engineering was employed to prepare high‐performance phosphorous‐doped biphase(1T/2H)MoS_(2)(P‐BMS)nanoflakes for hydrogen evolution reaction(HER).The doping of MoS_(2)with P atoms modifies its electronic structure and optimizes its electrocatalytic reaction kinetics,which significantly enhances its electrical conductivity and structural stability,which are verified by various characterization tools,including X‐ray photoelectron spectroscopy,high‐resolution transmission electron microscopy,X‐ray absorption near‐edge spectroscopy,and extended X‐ray absorption fine ***,the hierarchically formed flakes of P‐BMS provide numerous catalytic surface‐active sites,which remarkably enhance its HER *** optimized P‐BMS electrocatalysts exhibit low overpotentials(60 and 72 mV at 10 mA cm^(−2))in H_(2)SO_(4)(0.5 M)and KOH(1.0 M),*** mechanism of improving the HER activity of the material was systematically studied using density functional theory calculations and various electrochemical characterization *** study has shown that phase engineering is a promising strategy for enhancing the H*adsorption of metal sulfides.

关键词： 1T/2H MoS_(2) density functional theory electrocatalysts phase engineering phosphorous doping

Mechanical Modeling and Analysis of Stability Deterioration of Production Well During Marine Hydrate Depressurization Production

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China Ocean Engineering 2024年第2期38卷 338-351页

作者： SUN huan-zhao CHANG Yuan-jiang SUN Bao-jiang WANG kang CHEN Guo-ming LI Hao DAI Yong-guo Centre for Offshore Engineering and Safety Technology China University of Petroleum(East China)Qingdao 266580China School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China Jiangsu Shuguang Oil Tools Co. LtdTaizhou 225532China

Different from oil and gas production,hydrate reservoirs are shallow and unconsolidated,whose mechanical properties deteriorate with hydrate ***,the formations will undergo significant subsidence during depressurization,which will destroy the original force state of the production ***,existing research on the stability of oil and gas production wells assumes the formation to be stable,and lacks consideration of the force exerted on the hydrate production well by formation subsidence caused by hydrate decomposition during *** fill this gap,this paper proposes an analytical method for the dynamic evolution of the stability of hydrate production well considering the effects of hydrate *** on the mechanical model of the production well,the basis for stability analysis has been proposed.A multi-field coupling model of the force state of the production well considering the effect of hydrate decomposition and formation subsidence is established,and a solver is *** analytical approach is verified by its good agreement with the results from the numerical method.A case study found that the decomposition of hydrate will increase the pulling-down force and reduce the supporting force,which is the main reason for the stability *** higher the initial hydrate saturation,the larger the reservoir thickness,and the lower the production pressure,the worse the stability or even *** work can provide a theoretical reference for the stability maintaining of the production well.

关键词： natural gas hydrate production well depressurization production formation deformation stability deterioration