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关于设立面向全球科学研究基金的思考与建议
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作者 傅伯杰 张军泽 +2 位作者 姜维 吕一河 朱永官 《中国科学基金》 CSCD 北大核心 2024年第1期193-199,共7页
气候变化、健康危机和粮食安全等问题通常会超越国家间的地理边界,是典型的全球性挑战。随着不同挑战的日益加剧,设立全球科学研究基金已成为推动科技进步、探索创新解决方案和加强伙伴关系的重要手段。在此背景下,“研究设立面向全球... 气候变化、健康危机和粮食安全等问题通常会超越国家间的地理边界,是典型的全球性挑战。随着不同挑战的日益加剧,设立全球科学研究基金已成为推动科技进步、探索创新解决方案和加强伙伴关系的重要手段。在此背景下,“研究设立面向全球的科学研究基金”是我国“十四五”时期(2021—2025年)完善科技创新体制的重要举措。为推进这一举措落实,本文在分析主要发达国家(美国、加拿大、英国、德国、日本、澳大利亚)和欧盟针对全球挑战的科研基金资助经验和广泛调研研讨的基础上,从人才项目、研究项目和大科学装置项目三个方面提出了我国未来设立面向全球的科学研究基金的建议,并探讨了相应的遴选、评估和管理机制,以期促进我国科研资助体系的创新发展,逐步提升我国在全球挑战研究中的国际影响力。 展开更多
关键词 全球挑战 全球科研基金 资助体系 管理机制
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再论构造叠加晕找盲矿三个核心理论的创新性及应用效果
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作者 魏江 李惠 +10 位作者 禹斌 任良良 王旭 魏子鑫 李永才 王希君 司淑云 杨亚娟 骆雪飞 要悦稳 许丽云 《矿产勘查》 2024年第1期82-91,共10页
“原生晕轴向分带理论”、“原生叠加晕理论”和“构造叠加晕理论”是构造叠加晕找盲矿法指导发现异常→评价异常→深部预测的三个核心理论,是提高预测准确性的关键。“构造叠加晕理论”是用少而精的样品发现异常→强化弱异常→加大预... “原生晕轴向分带理论”、“原生叠加晕理论”和“构造叠加晕理论”是构造叠加晕找盲矿法指导发现异常→评价异常→深部预测的三个核心理论,是提高预测准确性的关键。“构造叠加晕理论”是用少而精的样品发现异常→强化弱异常→加大预测深度的一种理论,“原生晕轴向分带理论”和“原生叠加晕理论”相结合是异常评价、预测盲矿和判别矿体剥蚀程度的重要理论。构造叠加晕团队先后在17个省105个矿山邀请138次立项研究-预测应用,其中已有20个矿山提供了预测靶位验证证明,累计找到金金属量突破320 t,见矿效果非常好。实践进一步证明了三个核心理论在找盲矿中的正确性和先进性,也表明构造叠加晕找盲矿法在矿区深部及外围找盲矿是一种直接、准确、有效的方法。 展开更多
关键词 构造叠加晕找盲矿法 三个核心理论 创新性 找矿效果显著
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机场道面水平钻孔注浆材料的制备与性能研究
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作者 方学东 魏江 +1 位作者 刘雨星 冯自立 《重庆理工大学学报(自然科学)》 CAS 北大核心 2024年第1期212-220,共9页
为满足机场不停航施工道面下基层水平注浆工程对材料的需求,开展了复合硅酸盐水泥和硫铝酸盐水泥复配试验。制备出符合施工要求的硅酸盐-硫铝酸盐复合水泥砂浆,并使用维卡仪、截锥圆模、压力试验机等设备研究了材料的凝结时间、流动性... 为满足机场不停航施工道面下基层水平注浆工程对材料的需求,开展了复合硅酸盐水泥和硫铝酸盐水泥复配试验。制备出符合施工要求的硅酸盐-硫铝酸盐复合水泥砂浆,并使用维卡仪、截锥圆模、压力试验机等设备研究了材料的凝结时间、流动性、1d抗压强度等。结果表明:硫铝酸盐水泥掺加比例越高,凝结时间越短;水灰比及减水剂掺量对流动性影响较大,同时对其他性能有一定影响。在确认最佳配合比时,经圆柱体强度试件模拟的钻孔注浆和现场试验段重锤式弯沉仪及探地雷达实测结果表明:复合水泥砂浆具有良好的工作性能,道面强度及结构恢复至钻孔前水平,能满足机场不停航施工要求。 展开更多
关键词 注浆材料 复合水泥砂浆 机场道面 不停航施工 水平钻孔注浆
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“新能源汽车技术”课程思政的教学改革与实践
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作者 李莎 李梅竹 +2 位作者 王胜 卫江 周艳峰 《时代汽车》 2024年第16期70-72,共3页
文章以高职院校汽车专业群共享课“新能源汽车技术”课程为例,全面贯彻党的教育方针、落实立德树人根本任务,在教学实施过程中,结合1+X职业技能及实际工作岗位深挖思政元素,将习近平新时代中国特色社会主义思想贯穿到专业教学全过程,推... 文章以高职院校汽车专业群共享课“新能源汽车技术”课程为例,全面贯彻党的教育方针、落实立德树人根本任务,在教学实施过程中,结合1+X职业技能及实际工作岗位深挖思政元素,将习近平新时代中国特色社会主义思想贯穿到专业教学全过程,推进“课程思政”教学改革,积极探索“新能源汽车技术”课程思政课教学改革与实践。 展开更多
关键词 高职教育 课程思政 新能源汽车技术
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混合高斯噪声条件下稀疏表示方法及其在冲击类故障特征提取中的应用
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作者 魏江 罗杨 +2 位作者 第五振坤 兰海 曹宏瑞 《机械科学与技术》 CSCD 北大核心 2024年第6期917-924,共8页
传统稀疏表示方法因其在冲击类信号特征提取中的独特优势而在故障诊断领域被广泛研究。然而,传统稀疏表示理论基于对干扰噪声的高斯分布假设,导致其难以适用于多种噪声分布混合的实际现场。针对上述问题,提出一种混合高斯噪声条件下的... 传统稀疏表示方法因其在冲击类信号特征提取中的独特优势而在故障诊断领域被广泛研究。然而,传统稀疏表示理论基于对干扰噪声的高斯分布假设,导致其难以适用于多种噪声分布混合的实际现场。针对上述问题,提出一种混合高斯噪声条件下的冲击类故障特征稀疏表示方法。基于传统稀疏表示理论的贝叶斯框架,借助混合高斯分布的万有逼近性质,建立了基于db4小波字典的混合高斯噪声稀疏分解模型,并推导了基于EM(Expectation-maximum,EM)和ADMM(Alternating direction method of multipliers,ADMM)的优化求解算法用于模型求解。仿真和实验结果表明,所提出的方法能够有效提取混合噪声干扰下的冲击类微弱故障特征信号。 展开更多
关键词 冲击类故障 故障特征提取 稀疏分解 混合高斯噪声
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Lipid metabolism analysis in esophageal cancer and associated drug discovery 被引量:1
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作者 Ruidi Jiao wei jiang +3 位作者 Kunpeng Xu Qian Luo Luhua Wang Chao Zhao 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第1期1-15,共15页
Esophageal cancer is an upper gastrointestinal malignancy with a bleak prognosis.It is still being explored in depth due to its complex molecular mechanisms of occurrence and development.Lipids play a crucial role in ... Esophageal cancer is an upper gastrointestinal malignancy with a bleak prognosis.It is still being explored in depth due to its complex molecular mechanisms of occurrence and development.Lipids play a crucial role in cells by participating in energy supply,biofilm formation,and signal transduction processes,and lipid metabolic reprogramming also constitutes a significant characteristic of malignant tumors.More and more studies have found esophageal cancer has obvious lipid metabolism abnormalities throughout its beginning,progress,and treatment resistance.The inhibition of tumor growth and the enhancement of antitumor therapy efficacy can be achieved through the regulation of lipid metabolism.Therefore,we reviewed and analyzed the research results and latest findings for lipid metabolism and associated analysis techniques in esophageal cancer,and comprehensively proved the value of lipid metabolic reprogramming in the evolution and treatment resistance of esophageal cancer,as well as its significance in exploring potential therapeutic targets and biomarkers. 展开更多
关键词 Lipid metabolism Esophageal cancer PROGRESSION Treatment resistance New therapeutic targets
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A dual-RPA based lateral flow strip for sensitive,on-site detection of CP4-EPSPS and Cry1Ab/Ac genes in genetically modified crops 被引量:1
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作者 Jinbin Wang Yu Wang +7 位作者 Xiuwen Hu Yifan Chen wei jiang Xiaofeng Liu Juan Liu Lemei Zhu Haijuan Zeng Hua Liu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期183-190,共8页
Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSP... Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSPS and Cry1Ab/Ac was proposed and combined with a lateral flow immunochromatographic assay,named“Dual-RPA-LFD”,to visualize the dual detection of genetically modified(GM)crops.In which,the herbicide tolerance gene CP4-EPSPS and the insect resistance gene Cry1Ab/Ac were selected as targets taking into account the current status of the most widespread application of insect resistance and herbicide tolerance traits and their stacked traits.Gradient diluted plasmids,transgenic standards,and actual samples were used as templates to conduct sensitivity,specificity,and practicality assays,respectively.The constructed method achieved the visual detection of plasmid at levels as low as 100 copies,demonstrating its high sensitivity.In addition,good applicability to transgenic samples was observed,with no cross-interference between two test lines and no influence from other genes.In conclusion,this strategy achieved the expected purpose of simultaneous detection of the two popular targets in GM crops within 20 min at 37°C in a rapid,equipmentfree field manner,providing a new alternative for rapid screening for transgenic assays in the field. 展开更多
关键词 Genetically modifi ed crops On-site detection Lateral fl ow test strips Dual recombinase polymerase amplification (RPA)
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沙库巴曲缬沙坦联合马来酸左旋氨氯地平治疗原发性高血压伴稳定型心绞痛的效果
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作者 李学英 魏江 +2 位作者 李甜甜 董静 马鹏超 《中国心血管病研究》 CAS 2024年第3期255-260,共6页
目的探讨沙库巴曲缬沙坦联合马来酸左旋氨氯地平治疗原发性高血压伴稳定型心绞痛(EH+SAP)的效果。方法选取2021年5月~2023年4月新疆生产建设兵团第一师医院EH+SAP患者128例,采用随机数字表法分为两组,各64例。两组均给予常规治疗,对照... 目的探讨沙库巴曲缬沙坦联合马来酸左旋氨氯地平治疗原发性高血压伴稳定型心绞痛(EH+SAP)的效果。方法选取2021年5月~2023年4月新疆生产建设兵团第一师医院EH+SAP患者128例,采用随机数字表法分为两组,各64例。两组均给予常规治疗,对照组采用奥美沙坦联合马来酸左旋氨氯地平治疗,观察组采用沙库巴曲缬沙坦联合马来酸左旋氨氯地平治疗。两组均连续治疗8周后进行疗效评估。比较两组治疗前、治疗8周血压、心绞痛情况、硝酸甘油用量变化,并检测中性粒细胞/高密度脂蛋白胆固醇比值(NHR)、心血管调节肽(salusin-β)水平。分析治疗8周NHR、salusin-β与血压、心绞痛情况、硝酸甘油用量的关系。统计两组治疗期间不良反应发生率。结果观察组治疗总有效率高于对照组[92.19%(59/64)比78.13%(50/64),P<0.05];治疗8周后两组24 h平均收缩压(24 h SBP)[(124.26±8.58)mmHg比(129.15±9.04)mm Hg]、24 h平均舒张压(24 h DBP)[(84.46±6.21)mmHg比(88.12±6.77)mmHg]、收缩压变异性(SBPV)[(9.54±2.42)mmHg比(10.63±2.30)mmHg]、舒张压变异性(DBPV)[(7.59±1.54)mmHg比(8.32±1.43)mmHg]、心绞痛发作次数[(0.33±0.10)次/周比(0.44±0.13)次/周]、心绞痛持续时间[(2.73±0.61)min比(3.42±0.98)min]、硝酸甘油用量[(0.17±0.05)mg/周比(0.23±0.06)mg/周]、NHR[(4.32±0.89)比(4.79±0.93)]、salusin-β[(3.65±0.57)nmol/L比(3.96±0.55)nmol/L]降低,且观察组低于对照组(P均<0.05);两组治疗8周NHR、salusin-β与24 h SBP、24 h DBP、SBPV、DBPV、心绞痛发作次数、心绞痛持续时间、硝酸甘油使用量均呈正相关(P<0.05);治疗期间两组水肿、头晕、潮红、心悸、低血压发生率比较,差异无统计学意义(P>0.05)。结论沙库巴曲缬沙坦联合马来酸左旋氨氯地平对EH+SAP疗效显著,可有效控制患者血压,减轻心绞痛症状,可能与调节NHR、salusin-β水平变化有关,且安全性有保障。 展开更多
关键词 沙库巴曲缬沙坦 马来酸左旋氨氯地平 高血压 心绞痛 中性粒细胞 高密度脂蛋白胆固醇 心血管调节肽
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Synergistic catalysis of the N-hydroxyphthalimide on flower-like bimetallic metal-organic frameworks for boosting oxidative desulfurization
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作者 Jing He Kun Zhu +5 位作者 wei jiang Dong-Ao Zhu Lin-Hua Zhu Hai-Yan Huang Wen-Shuai Zhu Hua-Ming Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期674-682,共9页
Synergic catalytic effect between active sites and supports greatly determines the catalytic activity for the aerobic oxidative desulfurization of fuel oils.In this work,Ni-doped Co-based bimetallic metal-organic fram... Synergic catalytic effect between active sites and supports greatly determines the catalytic activity for the aerobic oxidative desulfurization of fuel oils.In this work,Ni-doped Co-based bimetallic metal-organic framework(CoNi-MOF)is fabricated to disperse N-hydroxyphthalimide(NHPI),in which the whole catalyst provides plentiful synergic catalytic effect to improve the performance of oxidative desulfurization(ODS).As a bimetallic MOF,the second metal Ni doping results in the flower-like morphology and the modification of electronic properties,which ensure the exposure of NHPI and strengthen the synergistic effect of the overall catalyst.Compared with the monometallic Co-MOF and naked NHPI,the NHPI@CoNi-MOF triggers the efficient activation of molecular oxygen and improves the ODS performance without an initiator.The sulfur removal of dibenzothiophene-based model oil reaches 96.4%over the NHPI@CoNi-MOF catalyst in 8 h of reaction.Furthermore,the catalytic product of this aerobic ODS reaction is sulfone,which is adsorbed on the catalyst surface due to the difference in polarity.This work provides new insight and strategy for the design of a strong synergic catalytic effect between NHPI and bimetallic supports toward high-activity aerobic ODS materials. 展开更多
关键词 Metal-organic frameworks DOPED BIMETALLIC N-HYDROXYPHTHALIMIDE Aerobic processes Oxidative desulfurization
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New insights in nano-copper chromite catalyzing ultrafine AP:Evaluation of dispersity and mixing uniformity
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作者 Yong Kou Peng Luo +8 位作者 Lei Xiao Yanping Xin Guangpu Zhang Yubing Hu Junqing Yang Hongxu Gao Fengqi Zhao wei jiang Gazi Hao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期120-133,共14页
Improving the application of nanomaterials has always been a research hotspot in the field of energetic materials(EMs)due to their obvious catalytic effect on the EMs,especially the uniformly dispersed nanomaterials.H... Improving the application of nanomaterials has always been a research hotspot in the field of energetic materials(EMs)due to their obvious catalytic effect on the EMs,especially the uniformly dispersed nanomaterials.However,few studies have reported the dispersion of nanomaterials.In this study,the dispersity and mixing uniformity of nano-CuCr_(2)O_(4)was evaluated based on the difference of solid UV light absorption between the nano-catalytic materials and EMs.The nano-CuCr_(2)O_(4)/ultrafine AP composites with different dispersity of nano-CuCr_(2)O_(4)were prepared by manual grinding and mechanical grinding with different grinding strength and griding time.And then,the absorbance of different samples at 212 nm was obtained by solid UV testing due to the high repeatability of the absorbance at 210-214 nm for three parallel experiments,and the dispersity of different samples was calculated through the established difference equation.Furthermore,the samples were characterized by XRD,IR,SEM,EDS,DSC and TG-MS,which confirmed that different mixing methods did not change the structure of the samples(XRD and IR),and the mixing uniformity improved with the increase of grinding strength and grinding time(SEM and EDS).The scientificity and feasibility of the difference equation were further verified by DSC.The dispersity of nano-CuCr_(2)O_(4)exhibits a positive intrinsic relationship with its catalytic performance,and the uniformly dispersed nano-CuCr_(2)O_(4)significantly reduces the thermal decomposition temperature of ultrafine AP from 367.7 to 338.8℃.The TG-MS patterns show that the dispersed nano-CuCr_(2)O_(4)advanced the thermal decomposition process of ultrafine AP by about 700 s,especially in the high temperature decomposition stage,and the more concentrated energy release characteristic is beneficial to further enhance the energy performance of AP-based propellants.The above conclusions show that the evaluation method of dispersity based on solid UV curves could provide new ideas for the dispersity characterization of nano-catalytic materials in EMs,which is expected to be widely used in the field of EMs. 展开更多
关键词 Nano-CuCr_(2)O_(4) Ultrafine AP Dispersity UVeVis diffuse reflectance spectroscopy Thermal decomposition
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Countermeasure against blinding attack for single-photon detectors in quantum key distribution
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作者 Lianjun jiang Dongdong Li +12 位作者 Yuqiang Fang Meisheng Zhao Ming Liu Zhilin Xie Yukang Zhao Yanlin Tang wei jiang Houlin Fang Rui Ma Lei Cheng weifeng Yang Songtao Han Shibiao Tang 《Journal of Semiconductors》 EI CAS CSCD 2024年第4期76-81,共6页
Quantum key distribution(QKD),rooted in quantum mechanics,offers information-theoretic security.However,practi-cal systems open security threats due to imperfections,notably bright-light blinding attacks targeting sin... Quantum key distribution(QKD),rooted in quantum mechanics,offers information-theoretic security.However,practi-cal systems open security threats due to imperfections,notably bright-light blinding attacks targeting single-photon detectors.Here,we propose a concise,robust defense strategy for protecting single-photon detectors in QKD systems against blinding attacks.Our strategy uses a dual approach:detecting the bias current of the avalanche photodiode(APD)to defend against con-tinuous-wave blinding attacks,and monitoring the avalanche amplitude to protect against pulsed blinding attacks.By integrat-ing these two branches,the proposed solution effectively identifies and mitigates a wide range of bright light injection attempts,significantly enhancing the resilience of QKD systems against various bright-light blinding attacks.This method forti-fies the safeguards of quantum communications and offers a crucial contribution to the field of quantum information security. 展开更多
关键词 quantum key distribution single photon detector blinding attack pulsed blinding attack COUNTERMEASURE quan-tum communication
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Electrocatalysts with atomic-level site for nitrate reduction to ammonia
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作者 Shuai Yin Rong Cao +4 位作者 Yifan Han Jiachangli Shang Jing Zhang wei jiang Guigao Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期642-668,共27页
Ammonia(NH_(3))is an important raw material for modern agriculture and industry,being widely demanded to sustain the sustainable development of modern society.Currently,the industrial production methods of NH_(3),such... Ammonia(NH_(3))is an important raw material for modern agriculture and industry,being widely demanded to sustain the sustainable development of modern society.Currently,the industrial production methods of NH_(3),such as the traditional Haber-Bosch process,have drawbacks including high energy consumption and significant carbon dioxide emissions.In recent years,the electrocatalytic nitrate reduction reaction(NO_(3)RR)powered by intermittent renewable energy sources has gradually become a multidisciplinary research hotspot,as it allows for the efficient synthesis of NH_(3)under mild conditions.In this review,we focus on the research of electrocatalysts with atomic-level site,which have attracted attention due to their extremely high atomic utilization efficiency and unique structural characteristics in the field of NO_(3)RR.Firstly,we introduce the mechanism of nitrate reduction for ammonia synthesis and discuss the in-situ characterization techniques related to the mechanism study.Secondly,we review the progress of the electrocatalysts with atomic-level site for nitrate reduction and explore the structure-activity relationship to guide the rational design of efficient catalysts.Lastly,the conclusions of this review and the challenges and prospective of this promising field are presented. 展开更多
关键词 Ammonia synthesis Nitrate reduction Electrocatalysts with atomic-level site Reaction mechanism In-situ characterization techniques
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Alternating current heating techniques for lithium-ion batteries in electric vehicles:Recent advances and perspectives
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作者 Xinrong Huang Jinhao Meng +5 位作者 wei jiang Wenjie Liu Kailong Liu Yipu Zhang Daniel-Ioan Stroe Remus Teodorescu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期679-697,共19页
The significant decrease in battery performance at low temperatures is one of the critical challenges that electric vehicles(EVs)face,thereby affecting the penetration rate in cold regions.Alternating current(AC)heati... The significant decrease in battery performance at low temperatures is one of the critical challenges that electric vehicles(EVs)face,thereby affecting the penetration rate in cold regions.Alternating current(AC)heating has attracted widespread attention due to its low energy consumption and uniform heating advantages.This paper introduces the recent advances in AC heating from the perspective of practical EV applications.First,the performance degradation of EVs in low-temperature environments is introduced briefly.The concept of AC heating and its research methods are provided.Then,the effects of various AC heating methods on battery heating performance are reviewed.Based on existing studies,the main factors that affect AC heating performance are analyzed.Moreover,various heating circuits based on EVs are categorized,and their cost,size,complexity,efficiency,reliability,and heating rate are elaborated and compared.The evolution of AC heaters is presented,and the heaters used in brand vehicles are sorted out.Finally,the perspectives and challenges of AC heating are discussed.This paper can guide the selection of heater implementation methods and the optimization of heating effects for future EV applications. 展开更多
关键词 Lithium-ion battery Low temperature Alternating current heating HEATER Electric vehicle
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Nondestructive technique for identifying nuclides using neutron resonance transmission analysis at CSNS Back-n
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作者 Sheng-Da Tang Yong-Hao Chen +72 位作者 Jing-Yu Tang Rui-Rui Fan Qiang Li Gong Li Dong Liu Zheng-Yao Jin Xing-Zhu Cui Tian-Xiang Chen Yi-wei Yang Rong Liu Han Yi Yang Li Zhen Yang Qi An Hao-Fan Bai jiang-Bo Bai Jie Bao Ping Cao Qi-Ping Chen Zhen Chen Zeng-Qi Cui An-Chuan Fan Chang-Qing Feng Fan-Zhen Feng Ke-Qing Gao Min-Hao Gu Chang-Cai Han Zi-Jie Han Guo-Zhu He Yong-Cheng He Yang Hong Yi-wei Hu Han-Xiong Huang wei-Hua Jia Hao-yu jiang wei jiang Zhi-jie jiang Ling Kang Bo Li Chao Li Jia-Wen Li Xiao Li Jie Liu Shu-Bin Liu Guang-Yuan Luan Chang-Jun Ning Bin-Bin Qi Jie Ren Zhi-Zhou Ren Xi-Chao Ruan Zhao-Hui Song Kang Sun Zhi-Xin Tan Li-Jiao Wang Peng-Cheng Wang Zhao-Hui Wang Zhong-wei Wen Xiao-Guang Wu Xuan Wu Li-Kun Xie Yong-Ji Yu Guo-Hui Zhang Lin-Hao Zhang Mo-Han Zhang Qi-wei Zhang Xian-Peng Zhang Yu-Liang Zhang Yue Zhang Zhi-Yong Zhang Mao-Yuan Zhao Lu-Ping Zhou Zhi-Hao Zhou Ke-Jun Zhu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期178-187,共10页
Nondestructive and noninvasive neutron assays are essential applications of neutron techniques.Neutron resonance transmission analysis(NRTA)is a powerful nondestructive method for investigating the elemental compositi... Nondestructive and noninvasive neutron assays are essential applications of neutron techniques.Neutron resonance transmission analysis(NRTA)is a powerful nondestructive method for investigating the elemental composition of an object.The back-streaming neutron line(Back-n)is a newly built time-of-flight facility at the China Spallation Neutron Source(CSNS)that provides neutrons in the eV to 300 MeV range.A feasibility study of the NRTA method for nuclide identification was conducted at the CSNS Back-n via two test experiments.The results demonstrate that it is feasible to identify different elements and isotopes in samples using the NRTA method at Back-n.This study reveals its potential future applications. 展开更多
关键词 CSNS White neutron beam NRTA Nuclide identification Nondestructive method
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Strong metal–support interaction boosts the electrocatalytic hydrogen evolution capability of Ru nanoparticles supported on titanium nitride
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作者 Xin Wang Xiaoli Yang +7 位作者 Guangxian Pei Jifa Yang Junzhe Liu Fengwang Zhao Fayi Jin wei jiang Haoxi Ben Lixue Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期245-254,共10页
Ruthenium(Ru)has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction(HER),owing to its inherent high activity and being the cheapest platinum-gr... Ruthenium(Ru)has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction(HER),owing to its inherent high activity and being the cheapest platinum-group metal.Herein,based on the idea of strong metal–support interaction(SMSI)regulation,Ru/TiN catalysts with different degrees of TiN overlayer over Ru nanoparticles were fabricated,which were applied to the alkaline electrolytic water.Characterizations reveal that the TiN overlayer would gradually encapsulate the Ru nanoparticles and induce more electron transfer from Ru nanoparticles to TiN support by the Ru–N–Ti bond as the SMSI degree increased.Further study shows that the exposed Ru–TiN interfaces greatly promote the H_(2) desorption capacity.Thus,the Ru/TiN-300 with a moderate SMSI degree exhibits excellent HER performance,with an overpotential of 38 mV at 10 mA cm^(−2).Also,due to the encapsulation role of TiN overlayer on Ru nanoparticles,it displays super long-term stability with a very slight potential change after 24 h.This study provides a deep insight into the influence of the SMSI effect between Ru and TiN on HER and offers a novel approach for preparing efficient and stable HER electrocatalysts through SMSI engineering. 展开更多
关键词 electronic structure hydrogen evolution reaction RUTHENIUM strong metal-support interaction titanium nitride
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A review on surface coating strategies for anti-hygroscopic of high energy oxidizer ammonium dinitramide
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作者 Hongyu Yang Fuyao Chen +6 位作者 Yiwen Hu Qiangqiang Lu Lei Xiao Yinglei Wang Fengqi Zhao wei jiang Gazi Hao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期237-269,共33页
Ammonium dinitramide(ADN),which has the advantages of high energy density,no halogen and low characteristic signal,is not only considered as a new high-energy oxidizer that is expected to replace the traditional oxidi... Ammonium dinitramide(ADN),which has the advantages of high energy density,no halogen and low characteristic signal,is not only considered as a new high-energy oxidizer that is expected to replace the traditional oxidizer ammonium perchlorate(AP)in solid propellants,but also a good performance explosive in itself.However,due to the strong hygroscopicity of ADN,its application in solid propellants and explosives is greatly limited.Solving the hygroscopicity of ADN is the key to realize the wide application of ADN.In this paper,we systematically review the research progress of anti-hygroscopic strategies of ADN coating.The surface coating methods are focusing on solvent volatilization,solvent-non-solvent,melt crystallization and atomic layer deposition technology.The characteristics of the different methods are compared and analyzed,and the basis for the classification and selection of the coating materials are introduced in detail.In addition,the feasibility of material for surface coating of ADN is evaluated by several compatibility analysis methods.It is highly expected that the liquid phase method(solvent volatilization method,solvent-non-solvent method)would be the promising method for future ADN coating because of its effective,safety and facile operation.Furthermore,polymer materials,are the preferred coating materials due to their high viscosity,easy adhesion,good anti-hygroscopic effect,and heat resistance,which make ADN weak hygroscopicity,less sensitive,easier to preserve and good compatibility. 展开更多
关键词 Ammonium dinitramide(ADN) Energetic materials Anti-hygroscopic Surface coating Compatibility analysis
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Phosphotungstic acid ionic liquid for efficient photocatalytic desulfurization:Synthesis,application and mechanism
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作者 Chenchao Hu Suhang Xun +5 位作者 Desheng Liu Junjie Zhang Minqiang He wei jiang Huaming Li Wenshuai Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期101-111,共11页
An efficient mass transfer process is a critical factor for regulating catalytic activity in a photocatalytic desulfurization system.Herein,a phosphotungstic acid(HPW)active center is successfully composited with a qu... An efficient mass transfer process is a critical factor for regulating catalytic activity in a photocatalytic desulfurization system.Herein,a phosphotungstic acid(HPW)active center is successfully composited with a quaternary ammonium phosphotungstate-based hexadecyltrimethylammonium chloride ionic liquid(CTAC-HPW)by the ion exchange method for the photocatalytic oxidative desulfurization of dibenzothiophene sulfide.The keggin structure of HPW and highly mass transfer performance of organic cations synergistically enhanced the photocatalytic activity towards the effective convertion of dibenzothiophene(DBT)with the excitation of visible light.The deep desulfurization(<10 mg·kg^(-1))is attained within 30 min,and well stability is demonstrated within 25 cycles.Moreover,the CTAC-HPW photocatalyst projects well selectivity to interference from coexisting compounds such as olefins and aromatic hydrocarbons and universality of dibenzothiophenes,for example,4-methyldibenzothiophene(4-MDBT)and 4,6-dimethyldibenzothiophene(4,6-DMDBT).Ultimately,a possible photocatalytic desulfurization mechanism is proposed according to the Gaschromatography-mass spectrometry(GC-MS),proving that the final product is the corresponding sulfone.The trapping experiment and electron spin resonance(ESR)analysis confirmed that h^(+)and,COOH played critical roles in the oxidation process.The work offers a practicable strategy for efficiently converting DBT to DBTO_(2) with added value. 展开更多
关键词 Photocatalytic desulfurization EXTRACTION Ionic liquid CTAC-HPW
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Optimization of extreme ultraviolet vortex beam based on high harmonic generation
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作者 肖礴 赵逸文 +6 位作者 程方晶 王革文 姜威 王一琛 胡杰 梁红静 马日 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期459-464,共6页
In high harmonic generation(HHG),Laguerre–Gaussian(LG) beams are used to generate extreme ultraviolet(XUV)vortices with well-defined orbital angular momentum(OAM),which have potential applications in fields such as m... In high harmonic generation(HHG),Laguerre–Gaussian(LG) beams are used to generate extreme ultraviolet(XUV)vortices with well-defined orbital angular momentum(OAM),which have potential applications in fields such as microscopy and spectroscopy.An experimental study on the HHG driven by vortex and Gaussian beams is conducted in this work.It is found that the intensity of vortex harmonics is positively correlated with the laser energy and gas pressure.The structure and intensity distribution of the vortex harmonics exhibit significant dependence on the relative position between the gas jet and the laser focus.The ring-like structures observed in the vortex harmonics,and the interference of quantum paths provide an explanation for the distinct structural characteristics.Moreover,by adjusting the relative position between the jet and laser focus,it is possible to discern the contributions from different quantum paths.The optimization of the HH vortex field is applicable to the XUV,which opens up a new way for exploiting the potential in optical spin or manipulating electrons by using the photon with tunable orbital angular momentum. 展开更多
关键词 high harmonic generation phase matching extreme ultraviolet vortex beam quantum path interference
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主编的话:再塑大学治理体系
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作者 魏江 《财经论丛》 北大核心 2024年第7期3-4,共2页
大学治理体系是高校各利益相关方共同参与、相互作用,以推动高校整体发展和实现人才培养、科学研究和社会服务等一系列功能的制度安排和运行体系。大学治理体系是以制度体系为核心,以组织架构为基础,涉及学科治理、学术治理、行政治理... 大学治理体系是高校各利益相关方共同参与、相互作用,以推动高校整体发展和实现人才培养、科学研究和社会服务等一系列功能的制度安排和运行体系。大学治理体系是以制度体系为核心,以组织架构为基础,涉及学科治理、学术治理、行政治理等多个方面。大学治理体系是大学运行的基石,与学校战略图、路线图和施工图一起形成运行系统,没有大学治理体系和治理能力现代化,就不可能建立起高水平大学。大学是具有独特个性的学术组织,其最大个性是,大学以学术共同体为治理制度设计的基点。 展开更多
关键词 大学治理体系 学术治理 高水平大学 行政治理 学术共同体 治理制度 利益相关方 施工图
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再塑培养体系
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作者 魏江 《财经论丛》 北大核心 2024年第5期3-4,共2页
当下有不少这样的声音:随着人工智能技术发展,外语可以由机器翻译了;随着数字技术发展,会计可以由智能取代了;随着大模型的出现,散文诗歌可以由AIGC代劳了……,似乎整个社会都在怀疑传统教育的合法性和价值性。这些观点有其合理性,但也... 当下有不少这样的声音:随着人工智能技术发展,外语可以由机器翻译了;随着数字技术发展,会计可以由智能取代了;随着大模型的出现,散文诗歌可以由AIGC代劳了……,似乎整个社会都在怀疑传统教育的合法性和价值性。这些观点有其合理性,但也不能以偏概全、一叶障目,一概否定传统教育模式,而应该守正创新。如果回顾第一次工业革命以来的经济社会发展,我们发现,有的行业会消亡,但一定有新的行业会产生;有的工种会消失,但一定有新的工种会出现;有的技能会退化,但思想、艺术、文化的创造会常青。 展开更多
关键词 人工智能技术 传统教育模式 第一次工业革命 一叶障目 机器翻译 培养体系 守正创新 数字技术发展
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