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Mechanistic Insights into Electrocatalytic Nitrogen Reduction Reaction on the Pd-W Heteronuclear Diatom Supported on C_(2)N Monolayer:Role of H Pre-Adsorption

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Energy & Environmental Materials 2023年第2期6卷 323-333页

作者： Zeyun Zhang xuefei xu Department of Energy and Power Engineering and Key Laboratory for Thermal Science and Power Engineering of Ministry of EducationCenter for Combustion EnergyTsinghua UniversityBeijing 100084China

The electrocatalytic N_(2) reduction reaction(eNRR)is a potential alternative to the Haber-Bosch process for ammonia(NH3)*** efforts have been made in eNRR catalyst research to promote the practical application of *** this work,by means of density functional theory calculations and the computational hydrogen electrode model,we evaluated the eNRR performance of 30 single metal atoms supported on a C_(2)N monolayer(M@C_(2)N),and we designed a new thermodynamically stable Pd-W hetero-metal diatomic catalyst supported on the C_(2)N monolayer(PdW@C_(2)N).We found that PdW@C_(2)N prefers to adsorb H over N_(2),and then,the pre-generated hydrogen-terminated PdW@C_(2)N selectively adsorbing N_(2) behaves as the actual functioning“catalyst”to catalyze the eNRR process,exhibiting excellent performance with a low overpotential(0.31 V),an ultralow NH3 desorption free energy(0.05 eV),and a high selectivity toward eNRR over hydrogen evolution reaction(HER).Moreover,PdW@C_(2)N shows a superior eNRR performance to its monomer(W@C_(2)N)and homonuclear diatom(W_(2)@C_(2)N)*** revealed mechanism indicates that the preferential H adsorption over N_(2) on the active site may not always hamper the eNRR process,especially for heteronuclear diatom *** work encourages deeper exploration on the competition of eNRR and HER on catalyst surfaces.

关键词： density functional theory electrochemistry heteronuclear diatom catalyst nitrogen reduction reaction

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基于深度学习的输电线路绝缘子故障检测方法

电气工程学报 2024年第2期19卷 325-334页

作者：杨桢刘易宸李鑫许雪飞辽宁工程技术大学电气与控制工程学院葫芦岛125105

针对航拍巡检高压输电线路上绝缘子目标易受复杂背景和部分遮挡影响,造成传统算法难以准确检测的问题,建立了一种基于改进YOLOv5的输电线路绝缘子检测模型。首先,利用GA+K的检测框优化算法对选择的模型进行改进,来提高识别精度;然后,在Y... 详细信息

针对航拍巡检高压输电线路上绝缘子目标易受复杂背景和部分遮挡影响,造成传统算法难以准确检测的问题,建立了一种基于改进YOLOv5的输电线路绝缘子检测模型。首先,利用GA+K的检测框优化算法对选择的模型进行改进,来提高识别精度;然后,在YOLOv5算法框架中融合CBAM模块来提升图像中故障目标区域的显著度;其次,采用高斯函数改进YOLOv5中的非极大值抑制方法,提高对遮挡目标的识别准确率;最后利用辽宁某电网公司提供的无人机巡检图像制作数据集,并将所提算法与4种经典目标检测算法进行比较。试验结果表明,相比于4种对比算法,该算法能够在保证较高检测精度的同时具有较好的实时性,并且平均检测精度可以达到95.1%,每张图片的检测时间为0.04 s,兼具目标检测的准确性和实时性。

关键词：绝缘子缺陷故障检测深度学习目标识别 YOLOv5

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Rationally tailoring interface characteristics of ZnO/amorphous carbon/graphene for heat-conduction microwave absorbers

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Nano Research 2022年第10期15卷 8677-8687页

作者： Maofan Zhou xuefei xu Gengping Wan Pengpeng Mou Shengjie Teng Guizhen Wang State Key Laboratory of Marine Resource Utilization in South China Sea Hainan UniversityHaikou 570228China

With the increasingly severe electromagnetic interference issue and the huge heat dissipation demand caused by the miniaturized and integrated electronic devices,exploring the heat-conduction microwave absorption(MA)materials is highly desired and remains a great ***,we reported the fabrication of ZnO/amorphous carbon(ZnO/AC)hybrid films covered on the surface of graphene(ZnO/AC/Graphene)to simultaneously apply as the MA and thermal management *** ZnO/AC coatings synthesized with the auxiliary of an atomic layer deposition(ALD)method are highly uniform and controllable,which can significantly improve the MA performance and thermal conduction properties of *** reflection loss(RL)of−55.4 dB and the effective absorption bandwidth of 5.3 GHz were achieved with thickness of 2.0 mm for ZnO/AC/Graphene at a low loading content(3 wt.%).The minimum RL of−57.9 dB can be obtained in the ZnO/AC/Graphene composites at a low frequency(7.8 GHz).Moreover,the absorption frequency can be regulated by changing the ZnO/AC which can be readily implemented by adjusting the ALD cycles of *** thermal conductivity of ZnO/AC/Graphene is up to 257.8 mW·m^(−1)·K^(−1),increased by 53.2%compared with natural *** enhancement mechanisms of microwave loss and heat conduction are systematically studied in *** work not only develops an excellent candidate,but also provides a novel strategy to design functional materials for heat-conduction MA application.

关键词： atomic layer deposition graphene microwave absorption heat conductivity

基于LMDI模型的南京都市圈土地利用碳排放效应及其影响因素

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安庆师范大学学报（自然科学版） 2024年第1期30卷 111-118页

作者：徐雪霏王楠陈红张振国安徽科技学院资源与环境学院安徽凤阳233100

本文基于南京都市圈2005—2020年的LUCC数据,通过土地利用动态度模型和碳排放核算模型,分析了该区域15年间的土地利用碳排放效应,并采用LMDI模型探究了影响因素。结果表明,2005—2020年,研究区建设用地增加了2586.47 km^(2),耕地减少256... 详细信息

本文基于南京都市圈2005—2020年的LUCC数据,通过土地利用动态度模型和碳排放核算模型,分析了该区域15年间的土地利用碳排放效应,并采用LMDI模型探究了影响因素。结果表明,2005—2020年,研究区建设用地增加了2586.47 km^(2),耕地减少2561.51 km^(2),林地、草地减少225.20 km^(2),其中建设用地增加以及耕地、林地、草地减少是土地利用类型变化的主要形式。同时净碳排放量从4191.51万吨增长到7867.26万吨,增长率达87.96%,建设用地增加是造成碳排放增长的最主要原因。南京、镇江、马鞍山的碳排放量占总量的61.77%,芜湖和扬州分别增长254.93%和36.46%,而且长江沿岸城市较高,碳排放量最小的是滁州,其次是宣城,两市林地面积占研究区总林地面积的74.60%。此外,土地利用碳排放强度、土地利用构成、经济水平和人口规模因素的贡献率平均为1.10、1.12、1.82和1.03,对碳排放起促进作用,而土地利用强度贡献率平均为0.55,是唯一持续起抑制作用的影响因素。

关键词：土地利用碳排放 LMDI模型南京都市圈

急性冠脉综合征合并恶性肿瘤患者冠脉介入术后的预后分析

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实用癌症杂志 2024年第3期39卷 502-504,508页

作者：张娟徐雪飞张莎莎韩大臻河南省胸科医院 450003

目的分析急性冠脉综合征(ACS)合并恶性肿瘤患者经冠脉介入术后的预后。方法回顾性分析84例行冠脉介入术治疗的ACS合并恶性肿瘤患者的病历有关资料。在患者行冠脉介入术治疗后进行2年随访,依据患者的临床结局将其分为生存组与死亡组。... 详细信息

目的分析急性冠脉综合征(ACS)合并恶性肿瘤患者经冠脉介入术后的预后。方法回顾性分析84例行冠脉介入术治疗的ACS合并恶性肿瘤患者的病历有关资料。在患者行冠脉介入术治疗后进行2年随访,依据患者的临床结局将其分为生存组与死亡组。运用多因素Logistic回归分析模型探究ACS合并恶性肿瘤患者行冠脉介入术治疗后死亡的影响因素。结果随访2年,84例行冠脉介入术治疗的ACS合并恶性肿瘤患者中,共14例死亡,70例生存。单因素分析显示:年龄、性别、高血压、体重指数(BMI)、陈旧性心肌梗死、高脂血症、血红蛋白(HB)、肠外抗凝治疗与ACS合并恶性肿瘤患者冠脉介入术后死亡无关(P>0.05),糖尿病、吸烟、脑钠肽(BNP)水平、血小板计数(PLT)与ACS合并恶性肿瘤患者冠脉介入术后死亡有关(P<0.05);多因素Logistic回归分析显示:糖尿病(OR=9.167,95%CI=2.311~36.360)、吸烟(OR=16.105,95%CI=3.294~78.734)、BNP水平升高(OR=19.759,95%CI=4.634~359.79)、PLT减少(OR=18.231,95%CI=3.954~230.64)为ACS合并恶性肿瘤患者冠脉介入术后死亡的主要影响因素(P<0.05)。结论 ACS合并恶性肿瘤患者经冠脉介入治疗后死亡率较高,死亡的发生与糖尿病、吸烟、BNP水平升高、PLT减少有关,临床需予以高度重视,并针对性开展医疗干预,以最大程度改善患者预后。

关键词：急性冠脉综合征恶性肿瘤冠脉介入术预后

国土空间碳排放时空演变特征分析——以南京都市圈为例

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安徽科技学院学报 2024年第3期38卷 58-69页

作者：徐雪霏戚云丽陈红张振国肖新安徽科技学院资源与环境学院安徽凤阳233100 南京达农生态景观规划设计研究院有限公司江苏南京210000 安庆师范大学资源与环境学院安徽安庆246133

目的:探究南京都市圈国土空间碳排放效应时空演变特征,分析南京都市圈国土空间所承载的碳排放,寻求合理碳减排途径。方法:采用GIS分析技术、国土空间转移矩阵和碳排放流动模型,探究南京都市圈国土空间碳排放效应时空演变特征。结果:2005... 详细信息

目的:探究南京都市圈国土空间碳排放效应时空演变特征,分析南京都市圈国土空间所承载的碳排放,寻求合理碳减排途径。方法:采用GIS分析技术、国土空间转移矩阵和碳排放流动模型,探究南京都市圈国土空间碳排放效应时空演变特征。结果:2005—2020年,南京都市圈各国土空间类型间相互转化面积达3484.79 km^(2),其中农业空间净减少2561.51 km^(2),城镇空间净增加2586.47 km^(2)。研究期内,净碳排放量由7.52634×10^(7)t增长到1.538615×10^(8)t,年均增长率为6.96%;能源消费碳排放量增长3.68595×10^(7)t,工业生产碳排放量增长4.20659×10^(7)t。2005—2010、2010—2015及2015—2020年期间,国土空间类型变化导致的碳流动量分别为-2.26907×10^(7)t、-1.04824×10^(7)t、-8.1115×10^(6)t。结论:2005—2020年南京都市圈国土空间结构变化明显,耕地保护的形势严峻,城镇化水平显著提升。2005—2020年净碳排放量呈持续增长趋势,能源消费碳排放和工业生产碳排放为南京都市圈最大碳源。南京、镇江、马鞍山的碳排放量占南京都市圈的57.17%以上,芜湖、扬州的碳排放量涨幅显著,分别增长241.17%和119.55%。碳排放量最小的是宣城市,其次是滁州市,两市碳汇量占研究区总体的62.52%。3个时期内的消极碳流动量远大于积极碳流动量,消极碳流动主要源于农业空间向城镇空间的转化,说明城镇空间的扩张蚕食大量农业空间。

关键词：国土空间碳排放碳流动模型转移矩阵南京都市圈

Metal-Organic Frameworks Offering Tunable Binary Active Sites toward HighlyEfficient Urea Oxidation Electrolysis

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Research 2022年第4期2022卷 309-320页

作者： xuefei xu Qingming Deng Hsiao-Chien Chen Muhammad Humayun Delong Duan Xia Zhang Huachuan Sun Xiang Ao Xinying xue Anton Nikiforov Kaifu Huo Chundong Wang Yujie Xiong School of Optical and Electronic Information Wuhan National Laboratory for OptoelectronicsOptics Valley LaboratoryHuazhong University of Science and TechnologyWuhan 430074China Physics Department and Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials Huaiyin Normal UniversityHuaian 223300China Center for Reliability Science and Technologies Chang Gung UniversityTaoyuan33302 TaiwanChina School of Chemistry and Materials Science University of Science and Technology of ChinaHefei230026 AnhuiChina Department of Physics College of ScienceShihezi UniversityXinjang 832003China Department of Applied Physics Ghent UniversityGent 9000Belgium

Electrocatalytic urea oxidation reaction(UOR)is regarded as an effective yet challenging approach for the degradation of urea in wastewater into harmless N2 and CO_(2).To overcome the sluggish kinetics,catalytically active sites should be rationally designed to maneuver the multiple key steps of intermediate adsorption and ***,we demonstrate that metal-organic frameworks(MOFs)can provide an ideal platform for tailoring binary active sites to facilitate the rate-determining steps,achieving remarkable electrocatalytic activity toward ***,the MOF(namely,NiMn_(0.14)-BDC)based on Ni/Mn sites and terephthalic acid(BDC)ligands exhibits a low voltage of 1.317 V to deliver a current density of 10 mA cm^(-2).As a result,a high turnover frequency(TOF)of 0.15 s^(-1) is achieved at a voltage of 1.4 V,which enables a urea degradation rate of 81.87%in 0.33 M urea *** combination of experimental characterization with theoretical calculation reveals that the Ni and Mn sites play synergistic roles in maneuvering the evolution of urea molecules and key reaction intermediates during the UOR,while the binary Ni/Mn sites in MOF offer the tunability for electronic structure and d-band center impacting on the intermediate *** work provides important insights into active site design by leveraging MOF platform and represents a solid step toward highly efficient UOR with MOF-based electrocatalysts.

关键词： solution steps Highly

药物涂层球囊扩张成形术用于合并冠心病的肿瘤限期手术患者的效果研究

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中国实用医刊 2024年第7期51卷 10-12页

作者：谢力民徐雪飞王晓明董金虎王记培杨鹏伟河南省胸科医院郑州450000

目的探讨合并冠心病的肿瘤限期手术患者应用冠状动脉药物涂层球囊(DCB)扩张成形术的临床效果。方法回顾性抽取2019年2月至2023年2月河南省胸科医院收治的冠状动脉重度狭窄合并肿瘤限期手术患者136例,所有患者均行DCB扩张成形术处理冠状... 详细信息

目的探讨合并冠心病的肿瘤限期手术患者应用冠状动脉药物涂层球囊(DCB)扩张成形术的临床效果。方法回顾性抽取2019年2月至2023年2月河南省胸科医院收治的冠状动脉重度狭窄合并肿瘤限期手术患者136例,所有患者均行DCB扩张成形术处理冠状动脉重度狭窄情况,DCB术后应用双联抗血小板(DAPT)治疗1个月,然后行肿瘤相关手术。记录患者的相关临床资料,记录患者DCB手术围术期急性心血管事件发生率、手术成功率、出血率等,并记录患者肿瘤手术后的心源性死亡、非心源性死亡、急性心肌梗死、恶性心律失常、出血、再次冠状动脉血运重建等术后不良事件发生率及复合终点。结果136例患者均安全完成DCB手术,手术成功率100%(136/136)。无院内急性心血管事件发生,满足肿瘤限期手术的时间要求。DCB术后发生消化道出血4例(2.94%,4/136),均为消化道肿瘤患者;发生泌尿系统出血2例(1.47%,2/136),均为泌尿系统肿瘤患者;均未输血。中位随访时间为18.8个月,随访中3例患者死亡,均为非心源性死亡;2例出血,均为消化系统出血;9例DCB术后再发心绞痛,再次入院行药物洗脱支架植入术;无急性及晚期血栓形成事件发生。结论冠状动脉DCB扩张成形术极大的缩短了DAPT时间,且出血风险小、心血管事件发生率低,在合并冠心病的肿瘤限期手术患者中具有较高的应用价值。

关键词：冠心病肿瘤限期手术药物球囊扩张成形术围术期

Mottled dolomite in the lower Cambrian Longwangmiao formation in the Northern Sichuan Basin, South China

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Petroleum 2024年第1期10卷 19-29页

作者： xuefei Yang Hao Tang Junyi Zhang Yao Du Ruifeng Tang Shuang Pan Xiang Zhou Yan xu State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Sichuan Provincial Key Laboratory of Gas Geology Southwest Petroleum University CCDC Chuandong Drilling Company Exploration Department Petrochina Southwest Oil& Gasfield Company

At the end of Early Cambrian time, the Sichuan basin（South China） was located in a wide carbonate platform, with hundreds of meters of carbonate deposited. The Longwangmiao Formation carbonate in Sichuan basin is partially to completely dolomitized, displaying a mottled texture in the northern area of the exposure. The mottled dolomitic limestone developed parallel to bedding, with shape irregular boundaries with limestone that has not been dolomitized. The mottled dolomite is composed of powder crystalline and finely crystalline dolomite, while the matrix limestone is composed of micritic calcite. the isotopic composition of mottled dolomite(δ13C = +0.29‰PDB, δ18O =-1.15‰PDB) is similar to that of micrite calcite(δ13C =-0.49‰PDB, δ18O =-1.45‰PDB). Both isotopic values and trace element data indicate that the dolomitized fluid is originated from sea water. Some beds contain gypsum pseudomorphs and mud cracks, indicating a shallow and evaporative environment with local high salinity during deposition. Dolomitization likely took place early, in part as a result of sea water salinity concentration. Trace fossils thalassinoides horizontalis, thalassinoides callianassa and planolites developed in the Longwangmiao Formation, and the sharp edges of mottled dolomite are similar to these trace fossils. The beds are intensely bioturbated. In the burrow network, the sediments and burrow fill were coarse and loose with little clay, and it is interpreted here as being easier to be dolomitized than the surrounding *** dolomitization is thus interpreted to have occurred in the burrow system, and the degree of dolomitization was related to the degree of bioturbation, which is controlled by the trace-making creatures.

关键词： Mottled dolomite Dolomitization Longwangmiao Formation Early Cambrian Northern Sichuan basin