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Unimolecular Reactions of E-Glycolaldehyde Oxide and Its Reactions with One and Two Water Molecules

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Research 2024年第1期2023卷 809-824页

作者： Yan Sun bo long Donald G.Truhlar Department of Physics Guizhou UniversityGuiyang 550025China College of Materials Science and Engineering Guizhou Minzu UniversityGuiyang 550025China Department of Chemistry Chemical Theory Centerand Supercomputing InstituteUniversity of MinnesotaMinneapolisMN 55455-0431USA

The kinetics of Criegee intermediates are important for atmospheric ***,the quantitative kinetics of Criegee intermediates are still very limited,especially for those with hydroxy ***,we calculate rate constants for the unimolecular reaction of E-glycolaldehyde oxide[E-hydroxyethanal oxide,E-(CH_(2)OH)CHOO],for its reactions with H_(2)O and(H_(2)O)_(2),and for the reaction of the E-(CH_(2)OH)CHOO…H_(2)O complex with H_(2)*** the highest level of electronic structure,we use W3X-L//CCSD(T)-F12a/cc-pVDZ-F12 for the unimolecular reaction and the reaction with water and W3X-L//DF-CCSD(T)-F12b/jun-cc-pVDZ for the reaction with 2 water *** the dynamics,we use a dual-level strategy that combines conventional transition state theory with the highest level of electronic structure and multistructural canonical variational transition state theory with small-curvature tunneling with a validated density functional for the electronic structure.

关键词： structure kinetics molecular

Surficial modification enabling planar Al growth toward dendrite-free metal anodes for rechargeable aluminum batteries

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Science China Chemistry 2024年第4期67卷 1341-1351页

作者： Wenhao Liu Yu Li bo long Haoyi Yang Lumin Zheng Ying Bai Feng Wu Chuan Wu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing 314019China

Al metal possesses ultrahigh theoretical volumetric capacity of 8,040 m Ah cm^(-3),and gravimetric capacity of 2,980 m Ah g^(-1),and thus is highly attractive for electrochemical energy ***,it suffers from several issues,such as the dendrite formation,during Al stripping-deposition cycling,which has been verified to account for the short circuit and limited cyclic ***,we use a facile and applicable method to in-situ reconstruct the Al anode surface with F-Al-O chemical bonds,which could preferentially induce the planar growth of Al along the interface plane,thus leading to the dendrite-free morphology evolution during the *** from F-Al-O chemical bonds on the surface of Al anodes,long lifespan of symmetric cells can be realized even under 1 m A cm^(-2)and 1 m Ah cm^(-2).Coupling the F-Al anode with graphite-based cathodes,high-voltage dual-ion Al metal batteries can be achieved with long-term cycle stability up to 1,200 cycles(at 0.5 m A cm^(-2)),surpassing the counterparts using pristine Al metal ***,the effectiveness of this surficial modification strategy is also elucidated with the aid of theoretical *** work provides novel insights on low-cost and facile strategies against the Al dendrite growth in aluminum batteries.

关键词： rechargeable aluminum batteries Al metal anode Al dendrite dual-ion batteries surficial modification

Design and high-power testing of offline conditioning cavity for CiADS RFQ high-power coupler

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Nuclear Science and Techniques 2024年第9期35卷 18-27页

作者： Ruo-Xu Wang Yuan He long-bo Shi Chen-Xing Li Zong-Heng Xue Tian-Cai Jiang Xian-bo Xu Lie-Peng Sun Zhou-Li Zhang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Lanzhou University Lanzhou 730000China

To validate the design rationality of the power coupler for the RFQ cavity and minimize cavity contamination,we designed a low-loss offline conditioning cavity and conducted high-power *** offline cavity features two coupling ports and two tuners,operating at a frequency of 162.5 MHz with a tuning range of 3.2 *** the installation angle of the coupling ring and the insertion depth of the tuner helps minimize cavity *** performed electromagnetic structural and multiphysics simulations,revealing a minimal theoretical power loss of 4.3%.However,when the cavity frequency varied by110 kHz,theoretical power losses increased to10%,necessitating constant tuner adjustments during *** simulations indicated that increased cavity temperature did not affect frequency *** completion of the offline high-power conditioning platform,we measured the transmission performance,revealing a power loss of 6.3%,exceeding the theoretical *** utilized efficient automatic range scanning and standing wave resonant *** fully condition the power coupler,a 15°phase difference between two standing wave points in the condition-ing system was ***,the maximum continuous wave power surpassed 20 kW,exceeding the expected target.

关键词： RFQ cavity Power coupler Offline conditioning Resonant cavity

Fracturing-flooding technology for low permeability reservoirs:A review

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Petroleum 2024年第2期10卷 202-215页

作者： Nianyin Li Shijie Zhu Yue Li Jingrui Zhao bo long Fei Chen Erzhen Wang Wentao Feng Yanan Hu Shubei Wang Chen Jiang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China CNPC Southwest Oil and Gas Field Company Exploration and Development Research Institute Chengdu 610051China CNPC Southwest Oil and Gas Field Company Shale Gas Research Institute Chengdu 610051China Western Drilling Tuha Underground Operation Company Turpan838200China Changqing Downhole Technical Service Company of Chuanqing Drilling Engineering Co. Ltd.CNPCXi’anChina Petroleum Technology Research Institute Petrochina Changqing Oilfield CompanyXi'anChina

The development of low-permeability oil and gas resources presents a significant challenge to traditional development *** address the problem of“no injection and no production”in low-permeability reservoirs,a novel fracture-injection-production integration technology named fracturing-flooding has been proposed by oilfield *** technology combines the advantages of conventional fracturing,water flooding,and chemical flooding,resulting in improved reservoir physical properties,increased injection,replenished energy,and increased oil displacement *** technology is especially suitable for low-permeability reservoirs that suffer from lack of energy,and strong ***-flooding technology has shown significant results and broad development prospects in some oilfields in *** paper analyzes the development status of fracturing-flooding technology from its development history,technical mechanism,technical characteristics,process flow,types of fracturing and oil displacement fluids,and field *** and numerical simulations of fracturingflooding technology are also *** results suggest that fracturing-flooding technology is more effective than conventional fracturing,water flooding,and chemical flooding in stimulating lowpermeability tight reservoirs and improving oil ***,it has a high input-output ratio and can be utilized for future reservoir stimulation and transformation.

关键词： Fracturing-flooding Enhanced oil recovery Low permeability reservoirs Water flooding Injection Chemical flooding Fracturing

Clinical Value of the Quantitative Flow Ratio to Predict long-term Target Vessel Failure in Patients with In-stent Restenosis after Drug-coated Balloon Angioplasty

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Current Medical Science 2024年第3期44卷 561-567页

作者： Xiang-qi WU long-bo LI Wei YOU Zhi-ming WU Lei ZHAO Zhi-hui WANG Pei-na MENG Bin LIU Fei YE Department of Cardiology Nanjing First HospitalNanjing Medical UniversityNanjing210006China Department of Cardiology The Second Hospital of Jilin UniversityJilin130000China

Objective The study sought to investigate the clinical predictive value of quantitative flow ratio(QFR)for the long-term target vessel failure(TVF)outcome in patients with in-stent restenosis(ISR)by using drug-coated balloon(DCB)treatment after a long-term *** This was a retrospective study.A total of 186 patients who underwent DCB angioplasty for ISR in two hospitals from March 2014 to September 2019 were *** QFR of the entire target vessel was measured *** primary endpoint was TVF,including target vessel-cardiac death(TV-CD),target vessel-myocardial infarction(TV-MI),and clinically driven-target vessel revascularization(CD-TVR).Results The follow-up time was 3.09±1.53 years,and 50 patients had *** QFR immediately after percutaneous coronary intervention(PCI)was significantly lower in the TVF group than in the no-TVF *** Cox regression analysis indicated that the QFR immediately after PCI was an excellent predictor for TVF after the long-term follow-up[hazard ratio(HR):5.15×10−5(6.13×10−8−0.043);Plong-term TVF was 0.925(area under the curve:0.886,95%confidence interval:0.834–0.938;sensitivity:83.40%,specificity:88.00;Plong-term follow-up in ISR patients who underwent DCB angioplasty.A lower QFR immediately after PCI was associated with a worse TVF outcome.

关键词： percutaneous coronary intervention in-stent restenosis target vessel failure quantitative flow ratio

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战国秦汉斜向互绞编织物的编织工艺研究

丝绸 2024年第2期61卷 115-124页

作者：黄天周旸龙博浙江理工大学纺织科学与工程学院(国际丝绸学院) 杭州310018 中国丝绸博物馆杭州310002

本文以战国秦汉时期的两件斜向互绞编织物为研究对象,通过模拟复原的方法对战国秦汉时期斜向互绞编织物的组织结构与编织工艺进行分析与探究。对比两者在结构、格眼、纹理、组边上的异同,发现通过变化基础结构中经线交织的方向和次数可... 详细信息

本文以战国秦汉时期的两件斜向互绞编织物为研究对象,通过模拟复原的方法对战国秦汉时期斜向互绞编织物的组织结构与编织工艺进行分析与探究。对比两者在结构、格眼、纹理、组边上的异同,发现通过变化基础结构中经线交织的方向和次数可以形成不同的组织结构和纹理效果。在编织工艺上,两者都使用斜向穿绞编法。其中普通组各编线间的编结变化和排列顺序以2个经线数为循环,编线在各行编结时的状态与编线数的奇偶和第一行编结时各编线的编结状态有关。

关键词：斜向互绞编织物战国秦汉编织工艺组织结构纹理格眼

时间戳服务到UTC(NIM)的溯源方法研究

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仪器仪表学报 2024年第2期45卷 176-183页

作者：张宇贾正森龙波王玉琢贵州省计量测试院贵阳550003 中国计量科学研究院北京100029

原子时标国家计量基准UTC(NIM)由中国计量科学研究院维护和保持,溯源至协调世界时(UTC),是统一全国时间频率量值的最高依据。随着信息技术的不断发展,时间戳服务被广泛应用于司法、医疗、金融、电子商务、知识产权等领域。根据我国在贸... 详细信息

原子时标国家计量基准UTC(NIM)由中国计量科学研究院维护和保持,溯源至协调世界时(UTC),是统一全国时间频率量值的最高依据。随着信息技术的不断发展,时间戳服务被广泛应用于司法、医疗、金融、电子商务、知识产权等领域。根据我国在贸易结算、医疗等领域对法制计量的需求,时间戳机构(TSA)提供的时间应溯源至UTC(NIM)以实现国内统一和国际互认。本文提出使用一种校准器对TSA提供的时间进行远程和本地评估。实验结果表明,在局域网进行本地校准时,TSA与UTC(NIM)时间偏差的不确定度(k=2)小于2 ms;在广域网环境下,即使校准器与TSA之间相距超过1000 km,TSA与UTC(NIM)时间偏差的不确定度(k=2)小于713 ms。

关键词：时间戳校准溯源性

体育教育训练学博士学位论文研究方法分析:现状、反思与创新

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北京体育大学学报 2024年第7期47卷 130-145页

作者：龙博马卫平湖南师范大学体育学院湖南长沙410012

体育教育训练学的研究方法创新是构建新的理论体系和范畴变革的根本路径,构建中国特色体育教育训练学学术体系必须创新研究方法。研究采用文献计量学的方法对2000—2022年1 101篇体育教育训练学博士学位论文的研究方法进行了分析、反思... 详细信息

体育教育训练学的研究方法创新是构建新的理论体系和范畴变革的根本路径,构建中国特色体育教育训练学学术体系必须创新研究方法。研究采用文献计量学的方法对2000—2022年1 101篇体育教育训练学博士学位论文的研究方法进行了分析、反思与展望。首先,研究发现,体育教育训练学博士学位论文在研究过程中借鉴多学科的理论和方法展开研究,推动研究方法综合化、融合化发展,除了使用常规研究方法外,还重视研究方法的不断创新,聚焦学科前沿问题,注重定量与定性研究相结合,提高研究成果准确性。其次,研究指出,体育教育训练学博士学位论文在研究方法使用中仍存在整合不足、概念泛化、层次错位、表述不规范等问题,尤其是提出观点和论断缺乏具有独立自主概念和范畴的问题较为突出。最后,研究从建设体育强国战略,保持竞技体育国际地位的客观需要,对体育教育训练学研究方法的创新进行了思考并提出以下建议:创新研究范式,构建中国特色体育教育训练学学术体系;关注计算扎根理论,解锁方法驱动引擎;坚持问题导向,倒逼研究方法创新。

关键词：体育教育训练学博士学位论文研究方法

育肥牛的防疫措施及保健对策探究——以贵州威宁彝族回族苗族自治县为例

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广东蚕业 2024年第8期58卷 59-61页

作者：龙波威宁彝族回族苗族自治县畜牧业发展服务中心贵州毕节553100

育肥牛的饲料利用率较高,养殖周期较短,肉质口感好,其产品在市场中备受消费者喜爱。然而由于各类疫病的影响,育肥牛的健康受到威胁,牛肉品质下降,无法保障养殖户的经济效益,不利于育肥牛产业健康发展。文章以威宁彝族回族苗族自治县为例... 详细信息

育肥牛的饲料利用率较高,养殖周期较短,肉质口感好,其产品在市场中备受消费者喜爱。然而由于各类疫病的影响,育肥牛的健康受到威胁,牛肉品质下降,无法保障养殖户的经济效益,不利于育肥牛产业健康发展。文章以威宁彝族回族苗族自治县为例,结合当地实际情况总结了育肥牛的防疫措施及保健相关对策,以期为相关工作者提供参考。

关键词：育肥牛防疫保健措施对策威宁县