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Vulnerability and Conservation of Nearshore Cetaceans to Increasing Vessel Traffic:The Indo-Pacific Humpback Dolphin in the South China Sea

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Journal of Ocean University of China 2024年第4期23卷 1003-1014页

作者： LUO Dingyu GUO Lang HUANG Nuoyan WANG Hongri ZENG Chen TANG Xikai XU Zhuo WU Yuping sun xian School of Marine Sciences Zhuhai Key Laboratory of Marine Bioresources and EnvironmentGuangdong Provincial Key Laboratory of Marine Resources and Coastal EngineeringPearl River Estuary Marine Ecosystem Research Sta-tionMinistry of EducationSun Yat-Sen UniversitySouthern Marine Science and Engineering Guangdong Labora-tory(Zhuhai)Zhuhai 519082China

A comprehensive risk assessment to evaluate the vulnerability of the nearshore cetaceans to increasing marine traffic is *** this study,the risk to Indo-Pacific humpback dolphins(Sousa chinensis)in the main habitats in China was assessed based on a semiquantitative spatial vulnerability analysis.85%of the(sub)population which overlapped with the lanes of ferries and/or cargo vessels,with exposure scores of 1.23±0.31(calculated based on the proportion of sea routes that overlap the dolphin’s range).A combination of high exposure to the sea routes and sensitivity to marine traffic would render the(sub)populations to be highly vulnerable(EPRE:5.21 and XM:4.47).A low frequency of vessels and an awareness of the ecology assures a low vulnerability(SH:2.43,EZ:2.73).Uncertainty scores were commonly lower for the higher vulnerable populations,and higher for the lower vulnerable populations,suggesting additional field data and more monitoring are *** years of field data have been used to analyze the influences of various types of marine traffic on humpback dolphin *** and non-fishing vessels were significantly different(χ^(2)=65.19,p<0.01).The humpback dolphins were attracted by fishing vessels(83.1%)but avoided non-fishing vessels(95.2%).We recommend a management with seasonal and geographical constraints,to balance economic development and environmental conservation.

关键词： Indo-Pacific humpback dolphin vessel impacts risk analysis protection strategy

Enhanced hydrogen evolution performance by 3D ordered macroporous Ru-CoP@NC electrocatalysts

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Rare Metals 2024年第3期43卷 1095-1107页

作者： Chen-Chen Zhang Sheng Wei Li-xian sun Yi-Fang Ouyang Fen Xu Hai-Liang Chu Hong-GePan Li-Xin Chen Xue-Zhang Xiao School of Material Science and Engineering Guilin University of Electronic TechnologyGuilin541004China School of Chemistry and Chemical Engineering Guangxi UniversityNanning530004China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen518055GuangdongChina Institute of Science and Technology for New Energy Xi'an Technological UniversityXi'an710021China School of Materials Science and Engineering Zhejiang UniversityHangzhou310058China

Electrocatalytic water splitting coupled with sustainable energies is identified as an environmentally friendly and renewable strategy to generate high-quality hydrogen for the fuel ***,the main challenge is to develop high performance,low cost and chemically stable electrocatalysts to decline the energy barriers and enhance the sluggish kinetics of hydrogen evolution reaction(HER).Herein,a three-dimensional hierarchically ordered macroporous Ru-CoP@NC electrocatalyst(3DOM Ru-CoP@NC)derived from ordered macro-microporous metal-organic frameworks has been prepared using the precursor@template and double-solvent *** prepared 3DOM Ru-CoP@NC catalyst exhibits an overpotential of 15 mV(j=10 mA·cm^(-2))and a reaction Tafel slope of 38 mV·dec^(-1)in alkaline electrolyte,which are superior to commercial Pt@C ***,the overpotential and reaction Tafel slope of this catalyst in acidic media are 45 mV and 50 mV·dec^(-1),*** outstanding HER activities of 3DOM Ru-CoP@NC catalysts are ascribed to the 3D highly interconnectedreticular nanospaces that can increase effective reaction active *** N dope d carbon framework improves the electronic properties and ***,the strong interaction of Ru and CoP nanoparticles also boosts the HER *** results indicate that 3DOM Ru-CoP@NC catalysts with high catalytic activities have a broad application prospect in the future.

关键词： Hydrogen evolution reaction Template method 3D ordered macroporous Ru-CoP@NC

Modulated noble metal/2D MOF heterostructures for improved hydrogen storage of MgH_(2)

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Rare Metals 2024年第4期43卷 1672-1685页

作者： Zeng-Yi Li Li-xian sun Fen Xu Yu-Mei Luo Yong-Peng Xia Sheng Wei Chen-Chen Zhang Ri-Guang Cheng Chao-Feng Ye Meng-Yuan Liu Ju-Lan Zeng Zhong Cao Hong-Ge Pan School of Material Science and Engineering Guilin University of Electronic TechnologyGuilin541004China School of Chemistry and Chemical Engineering Changsha University of Science and TechnologyChangsha410114China Institute of Science and Technology for New Energy Xi’an Technological UniversityXi’an710021China

The conjugation of external species with twodimensional(2D)materials has broad application *** this study,we have explored the potential of noble metal/2D MOF heterostructures in hydrogen ***,the MgH_(2)-Ni-MOF@Pd system has shown remarkable hydrogen desorption/sorption performances,starting to liberate hydrogen at 1810C,which is 2300C lower than that of pristine *** the catalytic effect of Ni-MOF@Pd,the dehydrogenation apparent activation energy of MgH2 is noticeably decreased from(133.5±17.5)to(34.58±1.87)kJ·moL^(-1),and the hydrogenation apparent activation energy is reduced from(70.41±7.43)to(25.78±4.64)kJ·moL^(-1),which is lowered by 63.4%.The fully-dehydrogenated MgH2-NiMOF@Pd composite rapidly uptakes hydrogen,with 2.62wt%at 100℃and 6.06 wt%at 150℃within 300 s,*** mechanism analysis of MgH2 catalyzed by Ni-MOF@Pd has revealed that the transformation of Mg_2Ni and Mg_2NiH_4 could act as a"hydrogen pump",providing numerous channels for fast diffusion and transport of hydrogen ***,in the dehydrogenation process,the element Pd reacts with MgH_(2)to form the MgPd alloy phase,which makes MgH_(2)take precedence to decompose through the Mg-Pd alloy rather than self-decomposition,further reducing thermal stability and improving de/hydrogenation *** synergistic effect of Mg-Pd,Mg_2Ni,and the special ultra-thin 2D sheet structure of the additive is the main reason for the good hydrogen storage property of MgH_(2)-Ni-MOF@*** findings provide inspiration for designing efficient multifunctional additives with unique morphologies to optimize the hydrogen desorption/sorption behaviors of hydrogen storage materials.

关键词： Hydrogen storage Magnesium hydride 2D metal-organic framework nanosheets Ni/Pd Synergistic catalysis

含下伏气的第一类天然气水合物藏开发实验与模拟研究进展

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化工进展 2024年第4期43卷 2091-2103页

作者：孙贤柳军王晓辉孙长宇陈光进中国石油大学(北京)化学工程与环境学院北京102249 济宁经济技术开发区管理委员会山东济宁272000

第一类天然气水合物藏由上部含水合物沉积层和下伏气-液两相流层组成,是目前天然气水合物开采的首选目标。本文对第一类天然气水合物藏特征及试采情况进行了介绍,并回顾了相关实验和数值模拟研究进展。实验研究方面总结了第一类水合物... 详细信息

第一类天然气水合物藏由上部含水合物沉积层和下伏气-液两相流层组成,是目前天然气水合物开采的首选目标。本文对第一类天然气水合物藏特征及试采情况进行了介绍,并回顾了相关实验和数值模拟研究进展。实验研究方面总结了第一类水合物储层的重塑方案和该类水合物藏的产气特性。指出第一类水合物藏在储层塑造方面存在一定的局限性,多数实验研究中合成的水合物储层其下伏气是没有多孔介质的纯气体,不能模拟实际带有下伏气层的水合物储层的传质过程。而且,不同产气阶段的产气速率差异明显,初始阶段产气速率明显更快。此外,适用于经典的第三类水合物藏分解特性的建模思路,即将甲烷水合物的分解描述为移动边界问题,假设水合物分解发生在尖锐界面上,不适用于第一类水合物藏分解的数值模拟研究,因为该类水合物储层在分解阶段同时出现多个分解前沿。文中同时提出了有关第一类水合物藏开发未来的研究方向,即扩大研究尺度和模拟自然海洋环境水合物储层受力情况,以更贴近自然水合物成藏环境,提高研究结论的可参考性。

关键词：第一类水合物藏重塑传热传质数值模拟

维普期刊数据库博看期刊

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心脏磁共振对隐匿性心源性栓塞的诊断价值

中国现代神经疾病杂志 2024年第2期24卷 75-78页

作者：孙文先宋波郑州大学第一附属医院神经内科 450052

心脏磁共振(CMR)广泛应用于心脏疾病的诊断与治疗,但在缺血性卒中领域的应用尚不明确。CMR作为一种无创性检查方法,在明确缺血性卒中病因机制方面发挥重要作用,可以识别隐匿性心源性栓塞。本文综述CMR在隐匿性心源性栓塞诊断中的应用,... 详细信息

心脏磁共振(CMR)广泛应用于心脏疾病的诊断与治疗,但在缺血性卒中领域的应用尚不明确。CMR作为一种无创性检查方法,在明确缺血性卒中病因机制方面发挥重要作用,可以识别隐匿性心源性栓塞。本文综述CMR在隐匿性心源性栓塞诊断中的应用,即对缺血性卒中潜在病因如心脏血栓、左心房增大、左心房纤维化、左心耳形态及罕见心肌病等的识别,以及其优劣性,以为临床早期识别隐匿性心源性栓塞提供参考。

关键词：磁共振成像缺血性卒中心脏综述

装甲钢低相变点马氏体焊缝金属韧性劣化及其控制

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焊管 2024年第8期47卷 9-18页

作者：孙咸太原理工大学焊接材料研究所太原030024

综述了装甲钢低相变点马氏体焊缝金属韧性劣化及其控制。结果表明,低相变点马氏体焊缝金属常温冲击韧性低于母材的韧性劣化或韧性不稳定现象,与不同焊接方法所形成的马氏体焊缝显微组织及其含氧量的差异密切相关。降低焊缝马氏体相变温... 详细信息

综述了装甲钢低相变点马氏体焊缝金属韧性劣化及其控制。结果表明,低相变点马氏体焊缝金属常温冲击韧性低于母材的韧性劣化或韧性不稳定现象,与不同焊接方法所形成的马氏体焊缝显微组织及其含氧量的差异密切相关。降低焊缝马氏体相变温度的相关化学元素和成分含量在一定程度上有利于改善焊缝韧性,但焊缝化学成分并不是影响焊缝韧性的唯一因素。GTAW试样比GMAW试样焊缝冲击韧性高,焊缝中的含氧量是焊缝冲击韧性提高的内在因素。以形成低相变点马氏体组织为目标焊缝化学成分的控制和以焊缝中氧含量极低焊接方法的选用原则,是控制装甲钢焊缝韧性的有效途径。

关键词：韧性低相变点马氏体焊缝装甲钢残余应力夹杂物

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钛型气保护药芯焊丝工艺质量影响因素综述

焊管 2024年第3期47卷 16-27页

作者：孙咸太原理工大学焊接材料研究所太原030024

综述了涉及钛型气保护药芯焊丝工艺质量的影响因素。结果表明,合理选用药芯添加物,严格控制熔敷金属中主要强化元素C、Mn、Si的含量,可以改善焊丝熔滴过渡形态,获得焊丝熔敷金属满意的力学性能。在Ar+CO_(2)二元混合保护气体中,随着CO_... 详细信息

综述了涉及钛型气保护药芯焊丝工艺质量的影响因素。结果表明,合理选用药芯添加物,严格控制熔敷金属中主要强化元素C、Mn、Si的含量,可以改善焊丝熔滴过渡形态,获得焊丝熔敷金属满意的力学性能。在Ar+CO_(2)二元混合保护气体中,随着CO_(2)含量增大,熔滴过渡形态从轴向变为非轴向滴状排斥过渡,接头的抗拉强度几乎没有影响,但熔敷金属的冲击吸收能明显下降。热输入较大时,焊丝工艺性变差;热输入居中时,焊丝工艺性较好。热输入对焊丝熔敷金属韧性的影响出现了对热输入敏感和不敏感两种情况。钛型气保护药芯焊丝工艺质量的三个影响因素控制原理各具特色。

关键词：钛型气保护药芯焊丝焊缝金属韧性焊丝成分热输入保护气体

T23/P23钢高强匹配焊缝金属接头再热裂纹表征

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钢管 2024年第2期53卷 17-27页

作者：孙咸太原理工大学焊接材料研究所山西太原030024

综述了T23/P23钢高强匹配焊缝金属接头再热裂纹的特征。结果表明,T23/P23耐热钢高强匹配接头再热裂纹倾向明显,焊后状态高强匹配接头具有较高的强度和可以接受的塑性和韧性。接头显微组织中的HAZ粗晶区碳化物析出、晶界的滑移及晶界的... 详细信息

综述了T23/P23钢高强匹配焊缝金属接头再热裂纹的特征。结果表明,T23/P23耐热钢高强匹配接头再热裂纹倾向明显,焊后状态高强匹配接头具有较高的强度和可以接受的塑性和韧性。接头显微组织中的HAZ粗晶区碳化物析出、晶界的滑移及晶界的脆化是再热裂纹产生的必要条件;影响HAZ组织的主要因素是母材中碳化物形成元素和残留元素的种类及含量。随接头拘束应力增大,再热温度升高时再热裂纹倾向增大。T23/P23钢接头中氢的行为是产生再热裂纹不可忽视的影响因素。生产中常用低应力化和低氢化综合工艺及参数,以及新型专用焊接材料等措施,使接头中的应力水平降低,氢含量最小化,控制再热裂纹形成条件,并获得了较满意的效果。

关键词： T23/P23钢高强匹配接头再热裂纹铁研试验扩散氢

基于工程应用的CW-GMAW熔滴过渡形态表征

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焊接 2024年第2期 63-73页

作者：孙咸太原理工大学焊接材料研究所太原030024

综述了涉及工程应用的冷丝熔化极气体保护焊(Cold wire gas metal arc welding,CW-GMAW)熔滴过渡形态特征。结果表明,在大电流、强规范、富氩混合气体保护下,CW-GMAW工艺的熔滴过渡形态呈喷射过渡;当电流较小、电弧电压较低时,可能为滴... 详细信息

综述了涉及工程应用的冷丝熔化极气体保护焊(Cold wire gas metal arc welding,CW-GMAW)熔滴过渡形态特征。结果表明,在大电流、强规范、富氩混合气体保护下,CW-GMAW工艺的熔滴过渡形态呈喷射过渡;当电流较小、电弧电压较低时,可能为滴状过渡,甚至在弧压很低时,呈现短路过渡形态。该工艺电弧发生偏向冷丝的位移,弧长变短甚至发生短路,与冷丝送进速率比增高及冷丝在电弧中产生大量金属蒸气时弧柱电阻下降有关。在具有富氩混合保护气体的相同工艺参数下,CWGMAW转变电流比GMAW降低了4%~7%。焊接工艺参数对CW-GMAW和GMAW工艺熔滴过渡形态的影响规律大致相近,但前者因涉及冷丝送进速率比和电极焊丝送进速度,以及它们的匹配等,使焊接电流的影响更为复杂。

关键词：熔滴过渡冷丝熔化极气体保护焊转变电流冷丝送进速率比金属蒸气产生

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