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Defence Technology（防务技术） 2024年第1期31卷 288-294页

作者： Er-hai An Xiao-xia Li Cun-juan Yu Ying-xin tan zi-jun Fan Qing-xia Li Peng Deng Xiong Cao School of Environment and Safety Engineering North University of ChinaTaiyuan030051PR China College of Safety and Emergency Management Engineering Taiyuan University of Science and TechnologyTaiyuan030024PR China

Fe/N-based biomass porous carbon composite(Fe/N-p Carbon) was prepared by a facile high-temperature carbonization method from biomass,and the effect of Fe/N-p Carbon on the thermal decomposition of energetic molecular perovskite-based material DAP-4 was *** porous carbonaceous materials was considered as the micro/nano support layers for in situ deposition of Fe/N ***/Np Carbon was prepared simply by the high-temperature carbonization *** was found that it showed the inherent catalysis properties for thermal decomposition of *** heat release of DAP-4/Fe/N-p Carbon by DSC curves tested had increased slightly,compared from DAP-4/Fe/N-p *** decomposition temperature peak of DAP-4 at the presence of Fe/N-p Carbon had reduced by 79°C from384.4°C(pure DAP-4) to 305.4°C(DAP-4/Fe/N-p Carbon-3).The apparent activation energy of DAP-4thermal decomposition also had decreased by 29.1 J/*** possible catalytic decomposition mechanism of DAP-4 with Fe/N-p Carbon was proposed.

关键词： Biomass materials Porous carbon DAP-4 Thermal decomposition Facile method

Atroposelective Synthesis of 2-Arylindoles via Chiral Phosphoric Acid-Catalyzed Direct Amination of Indoles

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Chinese Journal of Chemistry 2024年第7期42卷 731-735页

作者： Wen Bao Ye-Hui Chen Yu-Wei Liu Shao-Hua Xiang bin tan School of Pharmacy&StateKey Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhouGansu 730000China Shenzhen Grubbs Institute Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong 518055China

Indole-based atropisomers are a very important class of axially chiral ***,the atroposelective synthesis of axially chiral 2-arylindole remains largely *** this study,we report the successful synthesis of atropisomeric 2-arylindoles using direct amination of indoles with p-quinonediimines in the presence of chiral phosphoric acid as a *** acts as an aminating reagent through formal polarity inversion of *** malonate group on the 2-aryl of 2-indoles was found to be essen-tial for high enantioselectivity of the *** could be due to the additional interaction between the ester group and the cata-lyst,as well as the intramolecular hydrogen *** findings provide a new strategy for the asymmetric construction of 2-arylindole atropisomers.

关键词： Chiral phosphoric acid Quinonediimines Direct amination Nucleophilic addition Asymmetric catalysis Enantioselectivity Axially chiral 2-arylindole Atroposelective synthesis

Investigation of formaldehyde sources and its relative emission intensity in shipping channel environment

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Journal of Environmental Sciences 2024年第8期142卷 142-154页

作者： Jiaqi Liu Shanshan Wang Yan Zhang Yuhao Yan Jian Zhu Sanbao Zhang Tianyu Wang Yibing tan bin Zhou Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China Institute of Eco-Chongming(IEC) No.20 Cuiniao RoadShanghai 202162China Institute of Atmospheric Sciences Fudan UniversityShanghai 200433China National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary Fudan UniversityShanghai 200438China Institute of Digitalized Sustainable Transformation Big Data InstituteFudan UniversityShanghai 200433China

Formaldehyde(HCHO)is considered one of the most abundant gas-phase carbonyl compounds in the atmosphere,which can be directly emitted through transportation ***-Path Differential Optical Absorption Spectroscopy(LP-DOAS)was used to observe HCHO in the river channel of Wusong Wharf in Shanghai,China for the whole year of *** to the impact of ship activity,the annual average HCHO level in the channel is about2.5 times higher than that in the nearby campus *** explain the sources of HCHO under different meteorological conditions,the tracer-pair of CO and O_(x)(NO_(2)+O_(3))was used on the clustered air *** results of the source appointment show that primary,secondary and background account for 24.14%(3.34±1.19 ppbv),44.78%(6.20±2.04ppbv)and 31.09%(4.31±2.33 ppbv)of the HCHO in the channel when the air masses were from the mixed direction of the city and channel,*** performing background station subtraction at times of high primary HCHO values and resolving the plume peaks,directly emitted HCHO/NO_(2)in the channel environment and plume were determined to be mainly distributed between 0.2 and *** cargo ships with higher sailing speeds or main engine powers tend to have higher HCHO/NO_(2)*** the knowledge of NO_(2)(or NO_(x))emission levels from ships,this study may provide data support for the establishment of HCHO emission factors.

关键词： HCHO LP-DOAS Channel environment Ship emissions

Dielectric and energy storage properties of PbO–SrO–Nb_(2)O_(5)–Na_(2)O–Si thin films by annealing

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Rare Metals 2024年第1期43卷 351-355页

作者： Fei-Hu tan Qing-Meng Zhang Feng Wei Hong-bin Zhao Xiao Zhang Jun Du State Key Laboratory of Advanced Materials for Smart Sensing General Research Institute for Nonferrous MetalsBeijing 100088China Advanced Electronic Materials Institute General Research Institute for Nonferrous MetalsBeijing 100088China

Dielectric and energy storage properties of PbOSrO-Na_(2)O-Nb_(2)O_(5)-SiO_(2)(PSNNS) thin films with annealing temperature from 700 to 850 ℃ were investigated by measuring their capacitance-electric filed curve and hysteresis *** results show that the highest dielectric constant and energy density are 81.2 and 17.0 J·cm^(-3),respectively,which is obtained in the sample with annealing temperature of 800 ℃.Annealed from 700 to800 ℃,the dielectric constant and energy storage performance of PSNNS films are continuously ***,with annealing temperature up to 850 ℃,their dielectric constant decreases,which might be related with the removal of interfacial defects as a function of annealing *** is one of the causes of space charge phenomenon,resulting in the increase in dielectric ***,the micro structure analysis by X-ray diffraction(XRD) and transmission electron microscope(TEM) indicates that the change of crystallization phase and interfacial polarization takes responsibility to the results.

关键词： Thin film Pulse laser deposition Annealing temperature Energy storage density

Characteristics and suppression of beam distortion in a high repetition rate nanosecond stimulated Brillouin scattering phase conjugation mirror

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High Power Laser Science and Engineering 2024年第2期12卷 69-78页

作者： Yifu Chen Bowen tan Duo Jin bin Chen Zhenxu Bai Kun Wang Yulei Wang Zhiwei Lü School of Astronautics Harbin Institute of TechnologyHarbinChina Center for Advanced Laser Technology Hebei University of TechnologyTianjinChina Hebei Key Laboratory of Advanced Laser Technology and Equipment TianjinChina School of Energy and Environmental Engineering Hebei University of TechnologyTianjinChina

The stimulated Brillouin scattering phase conjugation mirror (SBS-PCM) based on liquid media is widely used in high-power laser systems due to its robust thermal load capacity, high energy conversion efficiency and improved beam quality. Nevertheless, with an increase in the pump repetition rate, thermally-induced blooming and optical breakdown can emerge, leading to distortions in the Stokes beam. In this study, we delved into the thermal effects in liquid SBS-PCMs employing hydrodynamic analysis, establishing a relationship between beam profile distortion and the thermal convection field. We calculated the temperature and convection velocity distribution based on the pump light parameters and recorded the corresponding beam profiles. The intensities of the beam profiles were modulated in alignment with the convection directions, reaching a velocity peak of 2.85 mm/s at a pump pulse repetition rate of 250 Hz. The residual sum of squares (RSS) was employed to quantify the extent of beam profile distortion relative to a Gaussian distribution. The RSS escalated to 7.8, in contrast to 0.7 of the pump light at a pump pulse repetition rate of 500 Hz. By suppressing thermal convection using a high-viscosity medium, we effectively mitigated beam distortion. The RSS was reduced to 0.7 at a pump pulse repetition rate of 500 Hz, coinciding with a twentyfold increase in viscosity, thereby enhancing the beam quality. By integrating hydrodynamic analysis, we elucidated and mitigated distortion with targeted solutions. Our research offers an interdisciplinary perspective on studying thermal effects and contributes to the application of SBS-PCMs in high-repetition-rate laser systems by unveiling the mechanism of photothermal effects.

关键词： beam profile high power high repetition rate stimulated Brillouin scattering phase conjugation mirror thermal convection

Integrating machine learning and CALPHAD method for exploring low-modulus near-β-Ti alloys

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Rare Metals 2024年第1期43卷 309-323页

作者： Hao Zou Yue-Yan Tian Li-Gang Zhang Ren-Hao Xue zi-Xuan Deng Ming-Ming Lu Jian-Xin Wang Li-bin Liu School of Computer Science and Engineering Central South UniversityChangsha 410083China School of Materials Science and Engineering Central South UniversityChangsha 410083China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Traditional theoretical and empirical calculation methods can guide the design of β-and metastable β-alloys for bio-titanium. However, it is still difficult to obtain novel near-β-Ti alloys with low modulus. This study developed a method that combines machine learning with calculation of phase diagrams(CALPHAD) to facilitate the design of near-β-Ti alloys. An elastic modulus database of Ti–Nb–Zr–Mo–Ta–Sn system was constructed first, and then three features(the electron to atom ratio, mean absolute deviation of atom mass, and mean electronegativity) were selected as the key factors of modulus by performing a three-step feature selection. With these features, a highly accurate model was built for predicting the modulus of near-β-Ti alloys. To further ensure the accuracy of modulus prediction, machine learning with the elastic constants calculated was leveraged by CALPHAD database. The root mean square error of the well-trained model can be as low as 6.75 GPa. Guided by the prediction of machine learning and CALPHAD, three novel near-β-Ti alloys with elastic modulus below 50 GPa were successfully designed in this study. The best candidate alloy(Ti–26Nb–4Zr–4Sn–1Mo–Ta) exhibits an ultra-low modulus(36.6 GPa) after cold rolling with a thickness reduction of 20%. Our method can greatly save time and resources in the development of novel Ti alloys, and experimental verifications have demonstrated the reliability of this method.

关键词： Near-β-Ti alloy Machine learning Calculation of phase diagram Low-modulus alloy Feature selection

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都市圈轨道交通多阶段交路一体化编制研究

铁道学报 2024年第2期46卷 22-29页

作者：谭彬西南交通大学交通运输与物流学院四川成都610031 广东省铁路建设投资集团有限公司广东广州525000

在都市圈轨道交通线网不断织密和互联互通背景下,不同时期的线网结构会影响运行交路方案。考虑都市圈轨道交通网在不同阶段的变化情况,研究都市圈轨道交通多阶段运行交路一体化编制问题。首先,以各阶段交路车型编组与开行频率、直达与... 详细信息

在都市圈轨道交通线网不断织密和互联互通背景下,不同时期的线网结构会影响运行交路方案。考虑都市圈轨道交通网在不同阶段的变化情况,研究都市圈轨道交通多阶段运行交路一体化编制问题。首先,以各阶段交路车型编组与开行频率、直达与换乘客流配流情况为决策变量,以最小化乘客旅行时间与交路运行里程为目标,考虑客流需求、服务频率、通过能力、交路设置规则、交路多阶段延续性等约束,构建都市圈区域线网多阶段运行交路一体化编制模型。以某都市圈新建城际快轨为例进行实证研究,结果表明,本方法一体化编制的不同阶段交路方案具有良好的延续性和稳定性;相比各线路分别运行本线交路模式,能够减少乘客因换乘增加的时间,节时比达到18%~19%。

关键词：铁路运输多阶段交路编制整数规划都市圈轨道交通互联互通

The new era of integrative medicine—the confluence of tradition and modernity

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Integrative Medicine Discovery 2024年第21期8卷 1-2页

作者： zi-bin Lu Third Level Research Laboratory of State Administration of Traditional Chinese Medicine School of Traditional Chinese MedicineSouthern Medical UniversityGuangzhou 510515China.

In the context of accelerated globalization and rapid advancements in science and technology,integrative medicine—combining traditional medicine with modern science—is emerging at the forefront of medical *** article focuses on the current research hotspots and frontiers in integrative *** field of integrative medicine has seen the emergence of numerous new research hotspots and cutting-edge technologies,which reveal the scientific foundations and application potential of traditional medicine from various perspectives.(1)Application of multi-omics technologies:multi-omics technologies,including metabolomics,transcriptomics,proteomics,and genomics,have become essential tools in integrative medicine *** analyzes metabolites within biological systems to elucidate the metabolic pathways and mechanisms of traditional *** advancements in high-throughput technologies have enabled more comprehensive and accurate profiling of metabolic changes induced by traditional medicines,facilitating the identification of bioactive compounds and their *** investigates the effects of traditional medicines on gene expression,revealing molecular mechanisms by comparing transcriptome data under different *** in single-cell RNA sequencing have allowed researchers to study the heterogeneity of cellular responses to traditional medicines,uncovering cell-specific therapeutic targets and pathways.

关键词： frontier medicines advancement

Modulation of d-orbital to realize enriched electronic cobalt sites in cobalt sulfide for enhanced hydrogen evolution in electrocatalytic water/seawater splitting

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Rare Metals 2024年第2期43卷 511-521页

作者： Jian-Peng Sun Yu Zheng zi-Sheng Zhang Xiang-Chao Meng zi-Zhen Li Key Laboratory of Marine Chemistry Theory and Technology(Ministry of Education) College of Chemistry and Chemical EngineeringOcean University of ChinaQingdao266100China Shanxi Institute of Energy Taiyuan030600China Department of Chemical and Biological Engineering Faculty of EngineeringUniversity of OttawaOttawaONK1N6 N5Canada

Herein,a novel single-atomic Pt doping and interface-rich CoS/Co(OH)_(2)(Pt-CoS/Co(OH)_(2)/C)electrocatalyst has been successfully *** from precise regulation of d-orbital electronic structure modulation on Co site,Pt-CoS/Co(OH)_(2)/C exhibited remarkable HER activity and high stability for hydrogen evolution in splitting both water(73 mV@10 mA·cm^(−2)) and seawater(87 mV@10 mA·cm^(−2)).Notably,atomic Pt doping was introduced into CoS/Co(OH)_(2),which could produce local unbalanced Coulombic force and significantly increased the number of S vacancies,and then expose abundant Co ***,Co(OH)_(2) in Pt-CoS/Co(OH)_(2)/C could act as the adsorption sites for H_(2)O in hydrogen evolution reaction *** functional theory results also proved that atomic Pt doping,S vacancies and Co(OH)_(2) coupling could result in the formation of enriched electronic Co sites and optimize d_(z2) orbital electronic structure,and then realize the depth upward shift of d-band center and enhance the adsorption of H*on Co sites.

关键词： Electrocatalysts Hydrogen evolution reaction Pt-CoS/Co(OH)_(2) d-band center Electronic structure Water/seawater electrolysis

Birth weight,ideal cardiovascular health metrics in adulthood,and incident cardiovascular disease

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Chinese Medical Journal 2024年第10期137卷 1160-1168页

作者： Ying Sun bin Wang Yuefeng Yu Yuying Wang Xiao tan Jihui Zhang Lu Qi Yingli Lu Ningjian Wang Department of Endocrinology and Metabolism Institute of Endocrinology and MetabolismShanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China School of Public Health Zhejiang UniversityHangzhouZhejiang 310058China Department of Medical Sciences Uppsala UniversityUppsala 75105Sweden Center for Sleep and Circadian Medicine The Affiliated Brain Hospital of Guangzhou Medical UniversityGuangzhouGuangdong 510370China Department of Epidemiology School of Public Health and Tropical MedicineTulane UniversityNew OrleansLA 70118USA Department of Nutrition Harvard T.H.Chan School of Public HealthBostonMA 02138USA Channing Division of Network Medicine Department of MedicineBrigham and Women’s Hospital and Harvard Medical SchoolBostonMA 02138USA

Background:Prenatal and postnatal factors may have joint effects on cardiovascular health,and we aimed to assess the joint association of birth weight and ideal cardiovascular health metrics(ICVHMs)prospectively in adulthood with incident cardiovascular disease(CVD).Methods:In the UK Biobank,227,833 participants with data on ICVHM components and birth weight and without CVD at baseline were *** ICVHMs included smoking,body mass index,physical activity,diet information,total cholesterol,blood pressure,and hemoglobin *** Cox proportional hazards model was used to estimate the hazard ratios(HRs)and 95%confidence intervals(CIs)in men and ***:Over a median follow-up period of 13.0 years(2,831,236 person-years),we documented 17,477 patients with incident *** with participants with birth weights of 2.5-4.0 kg,the HRs(95%CIs)of CVD among those with low birth weights was 1.08(1.00-1.16)in men and 1.23(1.16-1.31)in *** association between having a birth weighttaneous improvement of both prenatal and postnatal factors could further prevent additional cases in women.

关键词： Birth weight Health metrics Cardiovascular disease Adult Stroke Coronary heart disease