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Metrology for sub-Ray.eigh-length target positioning in~10^(22)W/cm^(2)laser-plasma experiments

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High Power Laser Science and engineering 2024年第3期12卷 90-105页

作者： e.A.Vishnyakov A.Sagisaka K.Ogura T.Zh.esirkepov B.Gonzalez-Izquierdo C.D.Armstrong T.A.Pikuz S.A.Pikuz W.yan T.M.Jeong S.Singh P.Hadjisolomou O.Finke G.M.Grittani M.Nevrkla C.M.Lazzarini A.Velyhan T.Hayakawa y.Fukuda J.K.Koga M.Ishino K.Kondo y.Miyasaka A.Kon M.Nishikino y.V.Nosach D.Khikhlukha I.P.Tsygvintsev D.Kumar J.Nejdl D.Margarone P.V.Sasorov S.Weber M.Kando H.Kiriyama y.Kato G.Korn K.Kondo S.V.Bulanov T.Kawachi A.S.Pirozhkov eLI Beamlines Facility The Extreme Light Infrastructure ERICDolníBrežanyCzech Republic Kansai Institute for Photon Science(KPSI) QSTKyotoJapan Central Laser Facility Rutherford Appleton LaboratorySTFCHarwell OxfordDidcotUK Institute for Open and Transdisciplinary Research Initiatives Osaka UniversityOsakaJapan HB11 energy Holdings FreshwaterAustralia Key Laboratory for Laser Plasmas(Ministry of education) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghaiChina Institute of Plasma Physics ASCR PragueCzech Republic FZU-Institute of Physics ASCR PragueCzech Republic Czech Technical University in Prague FNSPEPragueCzech Republic Institute of Laser engineering Osaka UniversityOsakaJapan Institute of Physics National Academy of Sciences of UkraineKyivUkraine ISTeQ AR YerevanArmenia

Tight focusing with very small f-numbers is necessary to achieve the highest at-focus ***,tight focusing imposes strong demands on precise target positioning in-focus to achieve the highest on-target irradiance We describe several near-infrared,visible,ultraviolet and soft and hard X-ray diagnostics employed in a~10^(22)W/cm^(2)laser±plasma *** used nearly 10 J total energy femtosecond laser pulses focused into an approximately1.3-μm focal spot on 5±20μm thick stainless-steel *** discuss the applicability of these diagnostics to determine the best in-focus target position with approximately 5μm accuracy(i.e.,around half of the short Ray.eigh length)and show that several diagnostics(in particular,3ωreflection and on-axis hard X-rays)can ensure this *** demonstrated target positioning within several micrometers from the focus,ensuring over 80%of the ideal peak laser intensity *** approach is relatively fast(it requires 10±20 laser shots)and does not rely on the coincidence of low-power and high-power focal planes.

关键词： laser-plasma interaction precise target positioning spectroscopy ultra-high intensity X-rays

In-situ forming ultra-mechanically sensitive materials for high-sensitivity stretchable fiber strain sensors

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National Science Review 2024年第06期 254-263页

作者： Rouhui yu Changxian Wang Xiangheng Du Xiaowen Bai yongzhong tong Huifang Chen Xuemei Sun Jing yang Naoji Matsuhisa Huisheng Peng Meifang Zhu Shaowu Pan State Key Laboratory for Modification of Chemical Fibers and Poly.er Materials College of Materials Science and Engineering Donghua University MOe Key Lab of Disaster Forecast and Control in engineering School of Mechanics and Construction Engineering Jinan University State Key Laboratory of Molecular engineering of Poly.ers Department of Macromolecular Science and Institute of Fiber Materials and Devices Fudan University Department of Cardiology Shanghai Xuhui Central HospitalZhongshan-Xuhui Hospital Fudan University Research Center for Advanced Science and Technology and Institute of Industrial Science The University of Tokyo

Fiber electronics with flexible and weavable features can be easily integrated into textiles for wearable applications. However, due to small sizes and curved surfaces of fiber materials, it remains challenging to load robust active layers, thus hindering production of high-sensitivity fiber strain sensors. Herein, functional sensing materials are firmly anchored on the fiber surface in-situ through a hydrolytic condensation *** anchoring sensing layer with robust interfacial adhesion is ultra-mechanically sensitive, which significantly improves the sensitivity of strain sensors due to the easy generation of microcracks during stretching. The resulting stretchable fiber sensors simultaneously possess an ultra-low strain detection limit of 0.05%, a high stretchability of 100%, and a high gauge factor of 433.6, giving 254-folds enhancement in sensitivity. Additionally, these fiber sensors are soft and lightweight, enabling them to be attached onto skin or woven into clothes for recording physiological signals, e.g. pulse wave velocity has been effectively obtained by them. As a demonstration, a fiber sensor-based wearable smart healthcare system is designed to monitor and transmit health status for timely intervention. This work presents an effective strategy for developing high-performance fiber strain sensors as well as other stretchable electronic devices.

关键词：

effects of building aspect ratio,diurnal heating scenario,and wind speed on reactive pollutant dispersion in urban street canyons

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Journal of environmental Sciences 2012年第12期24卷 2091-2103页

作者： Nelson y.O.tong Dennis y.C.Leung Department of Mechanical engineering The University of Hong Kong

A photochemistry coupled computational fluid dynamics （CFD） based numerical model has been developed to model the reactive pollutant dispersion within urban street canyons, particularly integrating the interrelationship among diurnal heating scenario （solar radiation affections in nighttime, daytime, and sun-rise/set）, wind speed, building aspect ratio （building-height-to-street-width）, and dispersion of reactive gases, specifically nitric oxide （NO）, nitrogen dioxide （NO2） and ozone （O3） such that a higher standard of air quality in metropolitan cities can be achieved. Validation has been done with both experimental and numerical results on flow and temperature fields in a street canyon with bottom heating, which justifies the accuracy of the current model. The model was applied to idealized street canyons of different aspect ratios from 0.5 to 8 with two different ambient wind speeds under different diurnal heating scenarios to estimate the influences of different aforementioned parameters on the chemical evolution of NO, NO2 and 03. Detailed analy.es of vertical profiles of pollutant concentrations showed that different diurnal heating scenarios could substantially affect the reactive gases exchange between the street canyon and air aloft, followed by respective dispersion and reaction. Higher building aspect ratio and stronger ambient wind speed were revealed to be, in general, responsible for enhanced entrainment of 03 concentrations into the street canyons along windward walls under all diurnal heating scenarios. Comparatively, particular attention can be paid on the windward wall heating and nighttime uniform surface heating scenarios.

关键词： photochemistry reactive pollutant dispersion building aspect ratio diurnal heating scenario wind speed urban streetcanyon

基于卷积神经网络的液化预测模型及可解释性分析

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岩土力学 2024年第9期45卷 2741-2753页

作者：龙潇孙锐郑桐中国地震局工程力学研究所地震工程与工程振动重点实验室黑龙江哈尔滨150080 地震灾害防治应急管理部重点实验室黑龙江哈尔滨150080

常规液化判别方法通常是半经验方法,存在人为因素干扰,成功率及均衡性不佳。现有的机器学习方法缺乏足够的样本支撑,存在一定的局限性。通过整合液化数据集,选取修正标准贯击数、细粒含量、土层深度、地下水位深度、总上覆应力、有效上... 详细信息

常规液化判别方法通常是半经验方法,存在人为因素干扰,成功率及均衡性不佳。现有的机器学习方法缺乏足够的样本支撑,存在一定的局限性。通过整合液化数据集,选取修正标准贯击数、细粒含量、土层深度、地下水位深度、总上覆应力、有效上覆应力、门槛加速度、循环剪应力比、剪切波速、震级与地表峰值加速度11个液化特征建立卷积神经网络(convolutional neural network,简称CNN)模型。引入边界合成少数过采样技术消除不平衡数据集的影响。将CNN模型与随机森林模型、逻辑回归模型、支持向量机模型、极致梯度提升模型和规范方法进行对比,并结合沙普利加性解释(SHapley Additive exPlanations,简称SHAP)分析输入特征对预测结果的影响趋势。结果表明,CNN模型准确率达92.58%,各项指标均优于其他4种机器学习模型和规范方法。对SHAP结果分析可知,修正标贯击数小于15的土层液化概率较高,循环剪应力比CSR小于0.25的土层更不易液化。各因素的影响规律均符合现有认知,预测模型合理可靠。

关键词：机器学习液化预测卷积神经网络边界合成少数过采样技术沙普利加性解释(SHAP)

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跨境电商平台与企业出口产品质量升级——基于阿里巴巴国际站大数据平台的分析

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世界经济与政治论坛 2024年第3期 138-156页

作者：潘彤刘斌顾聪青岛科技大学经济与管理学院对外经济贸易大学中国世界贸易组织研究院杭州师范大学经济学院

近年来,数字化驱动的跨境电商平台成为推动外贸高质量发展的新引擎。本文基于阿里巴巴国际站会员企业数据、中国工业企业数据与海关数据等微观数据,实证分析跨境电子商务平台对企业出口产品质量的影响及作用渠道。研究结果表明:首先,应... 详细信息

近年来,数字化驱动的跨境电商平台成为推动外贸高质量发展的新引擎。本文基于阿里巴巴国际站会员企业数据、中国工业企业数据与海关数据等微观数据,实证分析跨境电子商务平台对企业出口产品质量的影响及作用渠道。研究结果表明:首先,应用跨境电商平台能够推动企业出口产品质量升级,影响作用主要通过缓解融资约束、降低中间品搜寻成本、提升创新能力三条渠道实现。其次,跨境电商平台对企业出口产品质量的影响呈现异质性特征,对一般贸易企业、劳动密集型企业和生产率偏低的企业出口产品质量提升作用更明显。此外,信誉较好、集群商业信用较高的企业有利于发挥跨境电商平台的正向影响效应,使用跨境电商平台也有助于缓解侵蚀性竞争对企业出口产品质量的负面影响。总之,本文的研究为跨境电商赋能企业出口提质增效、建设贸易强国提供了重要的政策意涵和实践路径。

关键词：跨境电商平台阿里巴巴国际站企业出口产品质量贸易强国

Identification of the cytochrome P450s responsible for the biosynthesis of two ty.es of aporphine alkaloids and their de novo biosynthesis in yeast

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Journal of Integrative Plant Biology 2024年第8期66卷 1703-1717页

作者： Qishuang Li Xiang Jiao Xinyi Li Wenlong Shi ying Ma Xiangmei Tan Jingyi Gan Jimei Liu Jian yang Jian Wang Baolong Jin tong Chen Ping Su yujun Zhao yifeng Zhang Jinfu Tang Guanghong Cui yun Chen Juan Guo Luqi Huang School of Traditional Chinese Pharmacy China Pharmaceutical UniversityNanjing 211198China State Key Laboratory for Quality.ensurance and Sustainable Use of Dao-di Herbs National Resource Center for Chinese Materia MedicaChina Academy of Chinese Medical SciencesBeijing 100700China Department of Life Sciences Chalmers University of TechnologyGothenburg SE-41296Sweden State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaThe Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Aporphine alkaloids have diverse pharmacological activities;however,our understanding of their biosynthesis is relatively *** studies have classified aporphine alkaloids into two categories based on the configuration and number of substituents of the D-ring and have proposed preliminary biosynthetic pathways for each *** this study,we identified two specific cytochrome P450 enzy.es(CyP80G6 and CyP80Q5)with distinct activities toward(S)-configured and(R)-configured substrates from the herbaceous perennial vine Stephania tetrandra,shedding light on the biosynthetic mechanisms and stereochemical features of these two aporphine alkaloid ***,we characterized two CyP719C enzy.es(CyP719C3 and CyP719C4)that cataly.ed the formation of the methy.enedioxy bridge,an essential pharmacophoric group,on the A-and D-rings,respectively,of aporphine *** the functional characterization of these crucial cytochrome P450 enzy.es,we reconstructed the biosynthetic pathways for the two ty.es of aporphine alkaloids in budding yeast(Saccharomy.es cerevisiae)for the de novo production of compounds such as(R)-glaziovine,(S)-glaziovine,and *** study provides key insight into the biosynthesis of aporphine alkaloids and lays a foundation for producing these valuable compounds through synthetic biology.

关键词： aporphine alkaloids biosynthesis CyP719C CyP80 engineered yeast

基于“技术道德化”理论的生成式人工智能教育应用潜能与风险研究

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电化教育研究 2024年第7期45卷 12-18页

作者：童慧杨彦军江西科技师范大学教育学部江西南昌330038 南昌大学教育发展研究院江西南昌330031

随着生成式人工智能的快速发展及其在教育领域的广泛应用,国内外研究者围绕它及其背后的大语言模型教育应用问题展开了热烈的讨论,但大部分研究因缺乏对生成式人工智能技术原理的了解而在问题探讨中存在伊莉莎效应。研究首先在对生成式... 详细信息

随着生成式人工智能的快速发展及其在教育领域的广泛应用,国内外研究者围绕它及其背后的大语言模型教育应用问题展开了热烈的讨论,但大部分研究因缺乏对生成式人工智能技术原理的了解而在问题探讨中存在伊莉莎效应。研究首先在对生成式人工智能技术学原理进行深入剖析的基础上,从维贝克“人—技杂合”视角对生成式人工智能的本质展开技术哲学分析;其次,基于“技术道德化”理论分析了生成式人工智能教育应用的四大潜能和面临的五大风险挑战;最后,提出基于“人—技杂合”的思想从“设计者”和“使用者”两种视角构建“双向奔赴”的全球人工智能治理体系,将成为未来探索的重要方向。

关键词：生成式人工智能技术道德化大模型人—技杂合应用风险

Three-dimensional magnetic reconnection in complex multiple X-point configurations in an ancient solar-lunar terrestrial system

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Chinese Physics B 2024年第3期33卷 488-495页

作者：何向磊毛傲华孙萌萌邹继同王晓钢 School of Physics Harbin Institute of TechnologyHarbin 150001China Laboratory for Space environment and Materials Science Harbin Institute of TechnologyHarbin 150001China

Magnetic reconnection processes in three-dimensional(3D)complex field configurations have been investigated in different magneto-plasma systems in space,laboratory,and astrophysical ***-dimensional(2D)features of magnetic reconnection have been well developed and applied successfully to systems with symmetrical property,such as toroidal fusion plasmas and laboratory.experiments with an axial *** in asymmetric systems,the 3D features are inevitably different from those in the 2D *** reconnection structures in multiple celestial body systems,particularly star-planet-Moon systems,bring fresh insights to the understanding of the 3D geometry of ***,we take magnetic reconnection in an ancient solar-lunar terrestrial magneto-plasma system as an example by using its crucial parameters approximately.estimated already and also some specific applications in pathways for energy and matter transports among earth,ancient Moon,and the interplanetary magnetic field(IMF).Then,magnetic reconnection of the ancient lunar-terrestrial magnetospheres with the IMF is investigated numerically in this *** a 3D simulation for the earth-Moon-IMF system,topological features of complex magnetic reconnection configurations and dynamical characteristics of magnetic reconnection processes are *** is found that a coupled lunar-terrestrial magnetosphere is formed,and under various IMF orientations,multiple X-points emerge at distinct locations,showing three typical magnetic reconnection structures in such a geometry,i.e.,the X-line,the triple current sheets,and the A-B null *** results can conduce to further understanding of reconnection physics in 3D for plasmas in complex magnetic configurations,and also a possible mechanism for energy and matters transport in evolutions of similar astrophysical systems.

关键词： magnetic reconnection multiple X-points complex magneto-plasma system

揭示氨对正己酸生产影响的机制——影响途径、关键酶和微生物

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engineering 2024年第4期35卷 180-190页

作者： Qing-Lian Wu Ke-Xin yuan Wei-tong Ren Lin Deng Hua-Zhe Wang Xiao-Chi Feng He-Shan Zheng Nan-Qi Ren Wan-Qian Guo State Key Laboratory of Urban Water Resource and environment Harbin Institute of TechnologyHarbin 150090China College of Architecture and environment Sichuan UniversityChengdu 610065China State Key Laboratory of Urban Water Resource and environment School of Civil and Environmental EngineeringHarbin Institute of Technology(Shenzhen)Shenzhen 518055China College of Chemistry and Chemical engineering Qiqihar UniversityQiqihar 161006China

n-Caproate,which is produced via chain elongation(Ce)using waste biomass,can supply various fossilderived products,thus advancing the realization of carbon *** released from the degradation of nitrogen-rich waste biomass can act as a nutrient or an inhibitor in anaerobic bioprocesses,including Ce,with the distinction being primarily dependent on its ***,the optimal concentration of ammonia and the threshold of toxicity for open-culture n-caproate production using ethanol as an electron donor,along with the underlying mechanisms,remain *** study revealed that the optimal concentration of ammonia for n-caproate production was 2.0 g∙L^(-1),whereas concentrations exceeding this threshold markedly suppressed the Ce *** of the mechanism revealed the involvement of two forms of ammonia(i.e.,ammonium ions and free ammonia)in this inhibitory *** ammonia levels(5.0 g∙L^(-1))induced excessive ethanol oxidation and suppressed the reverse β-oxidation(RBO)process,directly leading to the enhanced activities of enzy.es(phosphotransacetylase and acetate kinase)responsible for acetate formation and diminished activities of butyryl-coenzy.e A(CoA):acetyl-CoA transferase,caproyl-CoA:butyryl-CoA transferase,and caproyl-CoA:acetyl-CoA transferase that are involved in the syntheses of n-butyrate and ***,the composition of the microbial community shifted from Paraclostridium dominance(at 0.1 g∙L^(-1)ammonia)to a co-dominance of Fermentimonas,Clostridium sensu stricto 12,and Clostridium sensu stricto 15 at 2.0 g∙L^(-1)***,these Ce-functional bacteria were mostly absent in the presence of excessive ammonia(5.0 g∙L^(-1)ammonia).Metagenomic analysis revealed the upregulation of functions such as RBO,fatty acid synthesis,K^(+)efflux,adenosine triphosphatase(ATPase)metabolism,and metal cation export in the presence of 2.0 g∙L^(-1)ammonia,collectively contributing to enhanced n-caproate produc

关键词： Ammonia inhibition Medium chain fatty acids n-Caproate enzy.e Metagenomics