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Generation and regulation of electromagnetic pulses generated by femtosecond lasers interacting with multitargets

Nuclear Science and Techniques 2024年第1期35卷 96-107页

作者： Ya-Dong Xia De-Feng Kong Qiang-You he Zhen guo Dong-Jun Zhang Tong Yang Hao Cheng Yu-Ze Li Yang Yan Xiao Liang Ping zhu Xing-Long Xie Jian-Qiang zhu Ting-Shuai Li Chen Lin Wen-Jun Ma Xue-Qing Yan State Key Laboratory of Nuclear Physics and Technology and Key Laboratory of HEDP of the Ministry of EducationCAPTPeking UniversityBeijing 100871China Beijing Laser Acceleration Innovation Center Beijing 101407China Institute of Guangdong Laser Plasma Technology Guangzhou 510540China National Laboratory on High Power Laser and Physics Shanghai Institute of Optics and FineChinese Academy of SciencesShanghai 201800China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China

Ultrashort and powerful laser interactions with a target generate intense wideband electromagnetic pulses(EMPs).In this study,we report EMPs generated by the interactions between petawatt(30 fs,1.4×10^(20) W/cm^(2))femtosecond(fs)lasers with metal flat,plastic flat,and plastic nanowire-array(NWA)*** analyses are conducted on the EMPs in terms of their spatial distribution,time and frequency domains,radiation energy,and *** results indicate that EMPs from metal targets exhibit larger amplitudes at varying angles than those generated by other types of targets and are enhanced significantly for NWA *** a plastic target holder and increasing the laser focal spot can significantly decrease the radiation energy of the ***,the composite shielding materials indicate an effective shielding effect against *** simulation results show that the NWA targets exert a collimating effect on thermal electrons,which directly affects the distribution of *** study provides guidance for regulating EMPs by controlling the laser focal spot,target parameters,and target rod material and is beneficial for electromagnetic-shielding design.

关键词： Electromagnetic pulses Laser plasma interaction Electromagnetic shielding Electron distribution

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14MeV中子硒同位素反应截面的测量

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高能物理与核物理 2006年第9期30卷 844-847页

作者：贺国珠拓飞孔祥忠兰州大学现代物理系

在14MeV中子能区用活化法测得了^(82)Se(n,2n)^(81m,g)Se,^(76)Se(n,2n)^(75)Se,^(78)Se(n,p)^(78)As,^(76)Se(n,p)^(76)As,^(74)Se(n,p)^(74)As和^(80)Se(n,α)^(77)Ge反应截面值,以^(93)Nb(n,2n)^(92m)Nb反应截面为中子注量标准,并且... 详细信息

关键词：中子反应截面硒活化法

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Tbx 4 and Tbx 5 gene expression associated with appendage development and its relationship with the absence of the pelvic fin in Pampus argenteus

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Journal of Oceanology and Limnology 2024年第2期42卷 580-593页

作者： Shun ZHANG Xiaojing zhu Lingzhu HU Kai LIAO Shanliang XU Danli WANG Chunyang guo School of Marine Science Ningbo UniversityNingbo 315211China Key Laboratory of Applied Marine Biotechnology Ningbo UniversityChinese Ministry of EducationNingbo 315211China

The Tbx family is first known through the study of their functions in the body and limbs,and its members Tbx4 and Tbx5 genes are important factors in determining the characteristics of the *** argenteus is one of the important economical marine fishes widely distributed in offshore ***,it is necessary to study the role of Tbx family genes in the deletion of pelvic fin in *** this study,we cloned Tbx4 and Tbx5 cDNA sequence of ***(GenBank:MH709128 and MH712458).The Western blot and real time PCR were used to detect the expressions of Tbx4 and Tbx5 in different developmental stages and tissues of *** addition,whole-mount in-situ hybridization was used to study the localization of Tbx4 and Tbx5 genes in different developmental stages of *** show that the translation of Tbx4 mRNA was inhibited during the critical period of pelvic fin *** different tissues,Tbx4 protein levels were the lowest in the abdominal epithelium,and even lower than that in the pectoral fin,suggesting that the protein expression was also inhibited in the abdominal epithelium of adult ***,the results indicated that upstream genes regulation led to the key stage-specific and low expression of Tbx4 during pelvic fin development and in the abdominal epithelium.

关键词： Stromateidae pelvic fin protein translation T-box aquaculture broodstock

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Spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation

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National Science Review 2024年第2期11卷 155-167页

作者： Peng he Meng-Yang Hu Jin-Hong Li Tian-Zhang Qiao Yi-Lin Lu Shou-Fei zhu Frontiers Science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the Earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. Deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

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Evaluation and projection of marine heatwaves in the South China Sea: insights from CMIP6 multi-model ensemble

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Acta Oceanologica Sinica 2024年第7期43卷 15-25页

作者： Kai Liu Kang Xu Tongxin Han Congwen zhu Nina Li Anboyu guo Xiaolu Huang National Marine Environmental Forecasting Center Beijing 100081China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China National Meteorological Center China Meteorological AdministrationBeijing 100081China Inner Mongolia Autonomous Region Meteorological Observatory Huhhot 010051China

This study evaluates the performance of 16 models sourced from the coupled model intercomparison project phase 6(CMIP6)in simulating marine heatwaves(MHWs)in the South China Sea(SCS)during the historical period(1982−2014),and also investigates future changes in SCS MHWs based on simulations from three shared socioeconomic pathway(SSP)scenarios(SSP126,SSP245,and SSP585)using CMIP6 *** demonstrate that the CMIP6 models perform well in simulating the spatial-temporal distribution and intensity of SCS MHWs,with their multi-model ensemble(MME)results showing the best *** reasonable agreement between the observations and CMIP6 MME reveals that the increasing trends of SCS MHWs are attributed to the warming sea surface temperature *** various SSP scenarios,the year 2040 emerges as pivotal juncture for future shifts in SCS MHWs,marked by distinct variations in changing rate and *** is characterized by an accelerated decrease in MHWs frequency and a notably heightened increase in mean intensity,duration,and total days after ***,the projection results for SCS MHWs suggest that the spatial pattern of MHWs remains consistent across future ***,the intensity shows higher consistency only during the near-term period(2021−2050),while notable inconsistencies are observed during the medium-term(2041−2070)and long-term(2071−2100)periods under the three SSP *** the nearterm period,the SCS MHWs are characterized by moderate and strong events with high frequencies and relatively shorter *** contrast,during the medium-term period,MHWs are also characterized by moderate and strong events,but with longer-lasting and more intense events under the SSP245 and SSP585 ***,in the long-term period,extreme MHWs become the dominant feature under the SSP585 scenario,indicating a substantial intensification of SCS MHWs,effectively establishing a near-permanent state.

关键词： marine heatwaves South China Sea global warming future projections CMIP6

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Sialyltransferase ST3GAL6 silencing reduces α2,3-sialylated glycans to regulate autophagy by decreasing HSPB8-BAG3 in the brain with hepatic encephalopathy

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第6期25卷 485-498页

作者： Xiaocheng LI Yaqing XIAO Pengfei LI Yayun zhu Yonghong guo Huijie BIAN Zheng LI Laboratory for Functional Glycomics College of Life SciencesNorthwest UniversityXi’an 710069China National Translational Science Center for Molecular Medicine Department of Cell BiologyFourth Military Medical UniversityXi’an 710032China Medical Experiment Center Shaanxi University of Chinese MedicineXianyang 712046China The Infectious Disease Department Gongli HospitalPudong New AreaShanghai 200135China

End-stage liver diseases,such as cirrhosis and liver cancer caused by hepatitis B,are often combined with hepatic encephalopathy(he);ammonia poisoning is posited as one of its main pathogenesis *** is closely related to autophagy,but the molecular mechanism of ammonia’s regulatory effect on autophagy in he remains *** is an essential form of *** the nervous system,abnormal sialylation affects various physiological processes,such as neural development and synapse ***3 β-galactoside α2,3-sialyltransferase 6(ST3GAL6)is one of the significant glycosyltransferases responsible for addingα2,3-linked sialic acid to substrates and generating glycan *** found that the expression of ST3GAL6 was upregulated in the brains of mice with he and in astrocytes after ammonia induction,and the expression levels of α2,3-sialylated glycans and autophagy-related proteins microtubule-associated protein light chain 3(LC3)and Beclin-1 were upregulated in ammonia-induced *** findings suggest that ST3GAL6 is related to autophagy in ***,we aimed to determine the regulatory relationship between ST3GAL6 and *** found that silencing ST3GAL6 and blocking or degrading α2,3-sialylated glycans by way of Maackia amurensis lectin-II(MAL-II)and neuraminidase can inhibit *** addition,silencing the expression of ST3GAL6 can downregulate the expression of heat shock proteinβ8(HSPB8)and Bcl2-associated athanogene 3(BAG3).Notably,the overexpression of HSPB8 partially restored the reduced autophagy levels caused by silencing ST3GAL6 *** results indicate that ST3GAL6 regulates autophagy through the HSPB8-BAG3 complex.

关键词： hepatic encephalopathy Hyperammonemia Autophagy ST3β-galactosideα2,3-sialyltransferase 6(ST3GAL6) heat shock proteinβ8(HSPB8)

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Analysis and optimization of stamping and forming process of bearing outer ring

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 227-237页

作者： Shichao zhu Yulu Ding Bing Long Hun guo Linhan Ouyang Wengang Chen Zhengyi Jiang College of Aeronautics and Mechanical Engineering Changzhou Institute of TechnologyChangzhou 213002China College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China eering University of WollongongWollongong NSW 2522Australia

To address the common issues of wrinkling,tearing,and uneven wall thickness in the actual sheet metal stamp-ing process of the outer ring of needle roller bearings,this study analyzes critical technical indicators such asforming limits,thickness distribution,and principal strains in the forming process in ***-dimensionalmodels of the concave and convex dies were *** effects of different process parameters,includingstamping speed,edge pressure,sheet metal thickness,and friction coefficient,on the quality of the forming partswere investigated by varying these ***,the orthogonal experimental method was used todetermine an optimal experimental group from multiple sets of *** was found that under the processparameters of a stamping speed of 3000 mm/s,edge pressure of 2000 N,sheet metal thickness of 0.9 mm,andfriction coefficient of 0.125,the forming quality of the outer ring of the bearing is ideal.

关键词： Plate stamping Bearing outer ring Mold design Optimization

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Buried interface bridging for inverted cesium-formamidinium triiodide perovskite solar cells with long operational stability

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Science China Chemistry 2024年

作者： Chenhui Zhang Chunjun Liang Fulin Sun Ting zhu Xinghai Huang Yuzhu guo Xinyu guo Kunyang Ge Dan Li Fangtian You Zhiqun he Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronic TechnologyBeijing Jiaotong University Department of Physics School of Physical Science and Engineering Beijing Jiaotong University

In the field of perovskite solar cells(PSCs), the research on defects in the buried interface has been relatively limited due to its non-exposure; however, this interface significantly impacts the performance enhancement of inverted PSCs. This study employs phenylethylammonium chloride(PEACl) molecules as a buffer layer to modify the buried interface of p-i-n structured PSCs,aiming to enhance the uniformity of self-assembled monolayers(SAMs) and facilitate the uniform nucleation and growth of perovskite films on the substrate. Furthermore, the introduction of the PEACl buffer layer effectively passivates defects at the bottom of the perovskite layer and notably enhances the crystal quality of the perovskite film by mitigating residual stress,thereby reducing nonradiative recombination loss. Following these optimizations, the MA-free PSCs treated with PEACl achieve a power conversion efficiency(PCE) of 24.11%, with significant improvements in storage, thermal stability, and operational stability. Particularly noteworthy is the device's performance in an unencapsulated state, whereas after 1,500 hours of continuous light operation stability testing, it retains 97% of its original efficiency. This study not only enriches the systematic understanding of the characteristics of the buried interface in PSCs but also contributes significantly to advancing the commercial production of perovskite photovoltaic technology.

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Machine Learning-Based Temperature and Wind Forecasts in the Zhangjiakou Competition Zone during the Beijing 2022 Winter Olympic Games

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Journal of Meteorological Research 2024年第4期38卷 664-679页

作者： zhuo SUN Jiangbo LI Ruiqiang guo Yiran ZHANG Gang zhu Xiaoliang YANG China Meteorological Administration Xiong'an Atmospheric Boundary Layer Key Laboratory Xiong'an New Area 071800 hebei Key Laboratory of Meteorology and Ecological Environment Shijiazhuang 050021 hebei Meteorological Observatory Shijiazhuang 050021 College of Computer and Cyber Security Hebei Normal UniversityShijiazhuang 050024

Weather forecasting for the Zhangjiakou competition zone of the Beijing 2022 Winter Olympic Games is a challenging task due to its complex *** weather prediction models generally perform poorly for cold air pools and winds over complex terrains,due to their low spatiotemporal resolution and limitations in the description of dynamics,thermodynamics,and microphysics in mountainous *** study proposes an ensemble-learning model,named ENSL,for surface temperature and wind forecasts at the venues of the Zhangjiakou competition zone,by integrating five individual models—linear regression,random forest,gradient boosting decision tree,support vector machine,and artificial neural network(ANN),with a ridge regression as meta *** ENSL employs predictors from the high-resolution ECMWF model forecast(ECMWF-HRES) data and topography data,and targets from automatic weather station *** categories of predictors(synoptic-pattern related fields,surface element fields,terrain,and temporal features) are fed into *** results demonstrate that ENSL achieves better performance and generalization than individual *** root-mean-square error(RMSE) for the temperature and wind speed predictions is reduced by 48.2% and 28.5%,respectively,relative to *** the gust speed,the performance of ENSL is consistent with ANN(best individual model) in the whole dataset,whereas ENSL outperforms on extreme gust samples(42.7% compared with 38.7% obtained by ECMWF-HRES in terms of RMSE reduction).Sensitivity analysis of predictors in the four categories shows that ENSL fits their feature importance rankings and physical explanations effectively.

关键词： machine learning ensemble learning post-processing cold air pools mountain Beijing 2022 Winter Olympic Games

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Advancing microarray fabrication:One-pot synthesis and highresolution patterning of UV-crosslinkable perovskite quantum dots

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Nano Research 2024年第9期17卷 8600-8609页

作者： Linfeng Yuan Dejian Chen Kun he Jiamin Xu Kunyuan Xu Jie Hu Sisi Liang Haomiao zhu CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Research Center of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021China

The development of highly efficient,solution-processable,and environmentally stable perovskite quantum dots(PQDs)is crucial for their accurate high-resolution patterning and subsequently enabling the practical deployment of PQD based emissive display *** study presents an innovative strategy for integrating all-inorganic PQDs and ultraviolet(UV)crosslinkable acrylate polymer at a structural and functional *** achievement is accomplished by meticulous design and one-pot synthesis of UV-crosslinkable CsPbX_(3)(X=Cl,Br,I)PQDs solution,which exhibit outstanding environmental *** the solution-processable characteristics of the resulting UV-crosslinkable PQDs,precise patterning of high-resolution(2μm,7608 pixels·in.^(-1))and colorful PQDs microarrays can be readily achieved through inkjet printing and high-throughput photolithography(~2μm in pitch line/space patterning).The UV cross-linked process guarantees a homogeneous distribution of PQDs,effectively mitigating coffee ring effect and improving the overall quality of stereoscopic *** photo-cured PQDs film,which undergoes free radical photopolymerization,displays an impressive photoluminescence quantum yield(PL QY)of up to 89.2%,reaching 98%of the value observed in the solution *** approach outlined in this research is both cost-effective and pragmatic,exhibiting tremendous promise for diverse system-level integrated optoelectronic devices,such as ultra-high-resolution micro-light-emitting device(micro-LED)displays.

关键词： perovskite quantum dots microarrays cross-linking strategy Inkjet printing photolithography

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