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Science China(Information Sciences) 2024年第7期67卷 335-336页

作者： kunfeng XIE liang HU Jianping CHEN Guiling WU State Key Laboratory of Advanced Optical Communication System and Networks Department of Electronic EngineeringShanghai Jiao Tong University

Optical fiber transmission has been widely used in communications and metrology, wherein optical frequency transfer (OFT) and optical physical layer secure key distribution (OKD) have become research hotspots [1, 2]. Moreover,OFT can perform a comparison between state-of-the-art optical atomic clocks and implement coherent optical phase transfer over long distances to support geodesy [1, 3].

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Euler’s First-Order Explicit Method–Peridynamic Differential Operator for Solving Population Balance Equations of the Crystallization Process

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 3033-3049页

作者： Chunlei Ruan Cengceng Dong kunfeng liang Zhijun Liu Xinru Bao Mathematics&Statistics School Henan University of Science&TechnologyLuoyang471023China Longmen Laboratory Luoyang471023China College of Vehicle and Traffic Engineering Henan University of Science&TechnologyLuoyang471023China

Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridynamic differential operator(EE–PDDO)was obtained for solving the one-dimensional population balance equation in crystallization.Four different conditions during crystallization were studied:size-independent growth,sizedependent growth in a batch process,nucleation and size-independent growth,and nucleation and size-dependent growth in a continuous process.The high accuracy of the EE–PDDO method was confirmed by comparing it with the numerical results obtained using the second-order upwind and HR-van methods.The method is characterized by non-oscillation and high accuracy,especially in the discontinuous and sharp crystal size distribution.The stability of the EE–PDDO method,choice of weight function in the PDDO method,and optimal time step are also discussed.

关键词： Population balance equation crystallization peridynamic differential operator Euler’s first-order explicit method

Energy and Exergy Analysis of a Cooling/Power Cogeneration Ejector Refrigeration System

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Journal of Thermal Science 2022年第2期31卷 448-462页

作者： YANG Mengke LI Xiuzhen WANG Lin YUAN Junfei WANG Zhanwei liang kunfeng Institute of Refrigeration and Air conditioning Henan University of Science and TechnologyLuoyang 471023China

The organic Rankine cycle is introduced into the conventional ejector refrigeration(CER)system to establish the low-grade heat-driven cooling/power cogeneration ejector refrigeration(CPC-ER)system using the isobutane as the refrigerant.In comparison with the CER system where external power is consumed by the circulating pump,the power output from the CPC-ER system is more than the power consumption of its circulating pump so that a portion of net power is derived from the CPC-ER system.Based on the mathematical model of thermodynamics,energy and exergy analysis of the CPC-ER system is carried out and compared with the CER system.The results reveal that the equivalent coefficient of performance(COP)of the CPC-ER system is 41.14%to 71.30%higher than that of the CER system,and the exergy efficiency of the CPC-ER system is 1.32 to 1.49 times higher than that of the CER system.Both the power produced by the turbine and the total exergy output from the CPC-ER system approach the maximum,as the generating temperature in the generator is up to 80°C.The CPC-ER system has the higher energy utilization efficiency than the CER system,and it is suitable for the cooling and power-required places with low-grade thermal sources.

关键词： ejector refrigeration exergy power consumption equivalent COP

Thermodynamic Evaluation of Transcritical CO_(2) Heat Pump Considering Temperature Matching under the Constraint of Heat Transfer Pinch Point

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Journal of Thermal Science 2021年第3期30卷 869-879页

作者： LIU Ruijian GAO Fengling liang kunfeng WANG Lin WANG Moran MI Guoqiang LI Yachao Institute of Refrigeration and Air-Conditioning Henan University of Science and TechnologyLuoyang 471003China

The non-linear temperature glide in the supercritical CO_(2) cooling process makes the heat transfer pinch point of heat exchanger show multiplicity,like size,location distribution and quantity,which makes the thermodynamic performance of the CO_(2) transcritical cycle more complex and eventually affects the evaluation of the optimal operating state of the system.Based on the second law of thermodynamics and the constraints of heat transfer pinch,a thermodynamic evaluation method of CO_(2) transcritical heat pump system was proposed according to the degree of temperature matching.The influence mechanism of multi-characteristic change of heat transfer pinch point on temperature matching degree and the effect of temperature matching degree on thermodynamic performance of CO_(2) transcritical heat pump system were discussed.The relationship between temperature matching degree,COP and exergy efficiency of the system was analyzed.It is considered that the change of temperature matching index value can clearly characterize the change trends of COP and exergy efficiency.That is,the smaller the temperature matching degree is,the closer the temperature distribution of heat transfer fluids on both sides of the heat exchanger is to Lorenz cycle,and the greater the COP and exergy efficiency are.Furthermore,by monitoring the outlet temperature of the CO_(2) cooler,which has an essential relationship with the temperature matching degree during the heat exchange process,the deviation between actual and optimal working condition can be judged online,which is beneficial to real-time evaluation of the working state of the system.

关键词： heat pump CO_(2)transcritical cycle temperature matching degree exergy COP pinch point

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胶东型金矿

岩石学报 2024年第6期40卷 1691-1711页

作者：杨立强邓军张良杨伟谢东汪龙邱昆峰李大鹏中国地质大学地质过程与矿产资源国家重点实验室深时数字地球前沿科学中心北京100083 自然资源部金矿成矿过程与资源利用重点实验室山东省金属矿产成矿地质过程与资源利用重点实验室山东省地质科学研究院济南250013 山东黄金地质研究院济南250101

胶东是全球唯一已知赋存于前寒武纪变质地体中的晚中生代巨型金矿省,其成矿系统独具特色,具体表现为:(1)位于陆内复合构造域,经历了多期重大构造-热事件,大规模金成矿作用受控于120±2Ma古太平洋板块俯冲方向变化及其诱发的软流圈上涌... 详细信息

胶东是全球唯一已知赋存于前寒武纪变质地体中的晚中生代巨型金矿省,其成矿系统独具特色,具体表现为:(1)位于陆内复合构造域,经历了多期重大构造-热事件,大规模金成矿作用受控于120±2Ma古太平洋板块俯冲方向变化及其诱发的软流圈上涌、岩石圈改造和伸展-挤压变形交替及控矿断裂剪压-剪张转换;(2)多重控矿构造和多样赋矿建造联合控制了不同规模和类型金矿的发育,形成了三山岛、焦家、招平、栖霞、郭即和牟乳六条NE向金矿带和三山岛-栖霞EW向富金廊带,导致了金矿化类型(焦家式/破碎带蚀变岩型、玲珑式/石英脉型、蓬家夼式/蚀变砾岩±角砾岩型、辽上式/黄铁矿-碳酸盐脉型)及其地质-地球化学特征的多样性;(3)主要矿化元素Au、Ag、Cu、Pb和Zn均达到工业利用要求,并有多种共/伴生关键金属超常富集;(4)不同金矿带中硫化物Pb同位素组成与探明金资源储量及到郯庐断裂带的距离线性相关,反映距离幔源流体主通道越近、金属硫化物中放射性成因Pb含量和幔源组分占比越多、金成矿强度越大;(5)区域总体相对均一的Δ199 Hg(平均~0.012‰)及Δ199 Hg/Δ201 Hg与金品位呈线性负相关,表明成矿物质来源于富集岩石圈地幔、且地幔被俯冲洋壳及其上覆沉积物交代的程度控制了金品位的高低;(6)区域恒定的Δ33 S同位素组成(~0‰)排除了巨量金源自太古宙变质基底及其重熔花岗岩的可能,重的δ34 S(平均9.0±3.7‰)来源于俯冲的古太平洋板片及其上覆沉积物的脱挥发份;不同金矿带Δ33 S/δ34 S与探明金资源储量及其到郯庐断裂带距离线性相关,反映成矿期地壳伸展程度控制了金成矿强度;(7)区域He-Ar和H-O同位素组成显示壳幔混合特征,焦家式金矿的成矿流体组成更靠近地幔、玲珑式金矿位于地幔与地壳过渡带;三山岛、焦家和招平金矿带的成矿流体相对接近幔源流体,而郭即金矿带具有相对开放的构造环境;不同金矿带氢-氧同位素组成和探明金资源储量正相关,可能表征了从西到东成矿流体通量和流体-岩石反应强度逐渐降低。基于对上述特征的总结,提出了胶东型金矿的成因模式,明确了其成矿地球动力学背景和深部驱动、巨量金属和流体及络合物来源、输运通道和方式、源→汇过程和机制、成矿后变化和保存等成矿系统形成的关键因素,确立了“拆离断裂系与基底活化带及幔源流体通道复合控矿”的勘查思路和“四步式”的勘查模型。综上,胶东金矿不同尺度的鉴别特征及其形成的关键因素明显不同于全球已知的其他金矿类型,难以被已有成矿模式所涵盖,属于一种新的金矿类型——胶东型,其成因模式对华北、华南、西伯利亚、西澳伊尔岗、北美怀俄明和南美圭亚那等陆内金矿床具有普适性;系列找矿突破则验证了该成因模式与勘查模型的合理性和适用性。因此,本文认为胶东型金矿是全球研究热点和重要的金矿勘查方向,而该地区找矿的主攻目标是资源量大且品位和产状稳定的破碎带蚀变岩型金矿。

关键词：矿床地质-地球化学特征成矿系统时-空结构成矿动力学控矿因素成因及勘查模型胶东型金矿

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以检测为基础的高校转基因试验基地安全管理研究

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实验技术与管理 2024年第6期41卷 226-231页

作者：颜晶莹倪亮黄冲平李坤峰沈星宇浙江大学农业试验站浙江杭州310058

转基因技术对选育高产、高品质的作物品种和全球粮食安全具有重要贡献。我国高度重视农业转基因技术的研究和发展,但转基因仍然存在一定的环境风险,需要被严格监管。高校转基因试验基地是开展转基因技术及其应用研究的重要平台。该文从... 详细信息

转基因技术对选育高产、高品质的作物品种和全球粮食安全具有重要贡献。我国高度重视农业转基因技术的研究和发展,但转基因仍然存在一定的环境风险,需要被严格监管。高校转基因试验基地是开展转基因技术及其应用研究的重要平台。该文从转基因植物的种植现状及其潜在风险出发,以浙江大学为例详细介绍了以转基因检测为基础的全方位监管溯源流程,包括从种子—幼苗—果实—秸秆—土壤残留根系等不同阶段的取样检测,提出了以检测为基础的高校转基因试验基地安全监管方式。

关键词：转基因植物安全管理转基因试验基地检测

Metallogenetic model of Jiaodong-type gold deposits,eastern China

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Science China Earth Sciences 2023年第10期66卷 2287-2310页

作者： Jun DENG Qingfei WANG liang ZHANG Shengchao XUE Xuefei LIU Lin YANG Liqiang YANG kunfeng QIU Yayun liang State Key Laboratory of Geological Process and Mineral Resources China University of GeosciencesBeijing100083China Frontiers Science Center for Deep-time Digital Earth China University of GeosciencesBeijing100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China

The genesis of giant gold provinces is an international scientific frontier,in which the source of a huge amount of gold and the drive for mineralization are key challenges.The mineralization intensity of the Jiaodong gold province in eastern China is a rare occasion in the world,because it owns gold reserves of~5500 tons within an area of less than 10,000 km^(2).The Jiaodong gold province formed in the superimposed domain of diverse tectonic regimes in an intracontinental setting.Paleoproterozoic regional peak metamorphism and Triassic continental collision are followed by the tectonic transition and gold mineralization at ca.120 Ma with time intervals of 1.9 billion years and about 100 million years,respectively.The Jiaodong gold deposits are different from orogenic and intrusion-related gold deposits in terms of the tectonic background,types of host rocks,and oreforming mechanism.These gold deposits show close spatial-temporal and genetic relationships to mafic igneous rocks,implying the derivation of ore-forming fluids from the metasomatic mantle domains.Mafic dykes in Jiaodong have negativeε_(Hf)(t)values of-29.9 to-9.1,Os content of 0.002-0.16 ppb,heavyδ^(18)O up to 8.23‰,and high initial^(187)Os/^(188)Os ratios of 0.1352-0.8858.These indicate that the lithospheric mantle was metasomatized by ancient crust-derived components.The lithospheric mantle in the western Jiaodong shows generally more enriched isotope features than that in the eastern part,which is explained to be an important reason for its huge gold resources.The mafic dykes show lighter Mg isotope characteristics(averageδ^(26)Mg of-0.33‰,n=50)and high Ca O content(overall greater than 6.5 wt%),indicating that the lithospheric mantle would also record the metasomatism by the carbonate rocks from the subducting oceanic slab.Under the background of the rollback of the subducting paleo-Pacific slab and the destruction of the North China Craton,partial melting of the lower crust would produce granitic magmas that led to the enrichment of gold in the r

关键词： Jiaodong-type gold deposits Mantle fluids Metasomatized lithospheric mantle Source of gold Tectonic regime transition

The Formation of the Jiaodong Gold Province

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 1801-1820页

作者： DENG Jun WANG Qingfei LIU Xuefei ZHANG liang YANG Liqiang YANG Lin QIU kunfeng GUO Linnan liang Yayun MA Yao State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China Chengdu Center China Geological SurveyChengdu 610081China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

Gold deposits in Jiaodong,termed Jiaodong-type,are tectonically located in the southeastern margin of the North China Craton.Their major features are reviewed in this paper to highlight the differences between Jiaodong deposits and other genetic types of gold deposits.The mineralization was synchronized with asthenosphere upwelling indicated by synore OIB-like mafic dike and large-scale crustal thinning suggested by decrease of Sr/Y from pre-ore to syn-ore granites.Asthenosphere upwelling induced by the roll-back of Paleo-Pacific Plate drove partial melting of lithospheric mantle and devolatilization,which induced the release of the ore-forming fluids.In concomitant with magmatic records,mineralization migrated from the western Jiaobei terrane(133–127 Ma)to the eastern Sulu orogenic belt(114–108 Ma),corresponding to the eastward roll-back of Paleo-Pacific Plate.Gold mineralization in Jiaodong formed in the transitions of ductile to brittle deformation,rapid to slow crustal uplift,and regional compression to extension.In the regional-scale,the gold deposits in the Jiaobei terrane are mostly situated at intersections between NE-trending faults and EW-trending basement faults,and gold orebodies dominantly controlled by the lithologic contacts between Precambrian metamorphic rocks and Mesozoic granites.The mineralization was dominated by the disseminated-veinlet ores related to quartz–sericite alteration in strong cataclasite-breccia zone,with subsidiary thick quartz-sulfide veins developed in secondary fault zones.The ore-forming fluids belong to a H_(2)O–CO_(2)–NaCl±CH_(4)system and show minor variations in salinity among different types of ore.Structure-fluid feedback involving fluid-rock reaction and hydrofracturing triggered the fluid phase separation and resultant gold deposition.The Jiaodong gold deposits are distinct from orogenic and intrusion-related gold deposits in terms of tectonic setting,origin of ore-forming fluids,and mechanism of gold deposition.

关键词： Jiaodong-type geodynamic trigger ore-controlling structure ore-forming fluids structure-fluid feedback mineralization model

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尾矿管道泄漏检测系统研究与应用

矿山机械 2024年第3期52卷 67-71页

作者：任林海陈冲梅昆峰梁远骥谭晓乐朱成睿洛阳栾川钼业集团股份有限公司河南洛阳471500 中信重工机械股份有限公司河南洛阳471039

目前,尾矿矿浆一般通过管道输送至尾矿坝或者处理车间,输送管道会因其本身质量问题、矿浆磨损、复杂环境等因素而出现泄漏。尾矿含有大量重金属离子,甚至砷、汞等污染物质,以及选矿作业中加入的各种化学药剂;因此,输送管道一旦泄漏就会... 详细信息

目前,尾矿矿浆一般通过管道输送至尾矿坝或者处理车间,输送管道会因其本身质量问题、矿浆磨损、复杂环境等因素而出现泄漏。尾矿含有大量重金属离子,甚至砷、汞等污染物质,以及选矿作业中加入的各种化学药剂;因此,输送管道一旦泄漏就会对周边环境造成严重危害。输送管道主要采用人工巡查,巡检过程中发现泄漏,需开挖检修,但发现泄漏的时间完全依赖巡检人员。

关键词：泄漏检测系统输送管道管道输送化学药剂处理车间污染物质尾矿坝

实习护生自我效能感在人文关怀能力与职业获益感间的中介效应

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循证护理 2024年第13期10卷 2444-2447页

作者：周红颜杨西宁张文龙曾琪茜苏琳梁飘李亚如廖坤锋广西中医药大学广西530000 广西壮族自治区民族医院济南市中心医院

目的:探讨实习护生自我效能感在人文关怀能力与职业获益感间的中介效应。方法:便利抽取2022年10月1日—12月1日广西壮族自治区南宁市某三级甲等综合医院的300名实习护生为研究对象。采用一般资料调查问卷、关怀能力量表、一般自我效能... 详细信息

目的:探讨实习护生自我效能感在人文关怀能力与职业获益感间的中介效应。方法:便利抽取2022年10月1日—12月1日广西壮族自治区南宁市某三级甲等综合医院的300名实习护生为研究对象。采用一般资料调查问卷、关怀能力量表、一般自我效能感量表和护士职业获益感量表对实习护生进行调查并进行相关分析及中介效应分析。结果:实习护生人文关怀能力、自我效能感、职业获益感总分分别为(180.30±17.42)分、(30.37±4.66)分、(127.76±15.47)分;人文关怀能力、自我效能感与职业获益感总分均呈正相关(r值分别为0.585,0.476,均P<0.01);自我效能感在实习护生人文关怀能力与职业获益感间存在部分中介作用,占总效应的20.19%。结论:实习护生人文关怀能力、自我效能感和职业获益感处于中等偏上水平,护理管理者在重视实习护生人文关怀能力培养的同时还应注重自我效能感的培养,进而提高实习护生的职业获益感。

关键词：实习护生人文关怀能力自我效能感职业获益感中介效应