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Feedback of Efficient Shock Acceleration on Magnetic-field Structure Inside Young Type Ia Supernova Remnants

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Research in Astronomy and Astrophysics 2024年第6期24卷 234-244页

作者： jun-yu Shen Bi-Wen Bao Li Zhang Department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan UniversityKunming 650091China Key Laboratory of Statistical Modeling and Data Analysis of yunnan Province Yunnan UniversityKunming 650091China

Using an effective adiabatic index γ_(eff) to mimic the feedback of efficient shock acceleration,we simulate the temporal evolution of a young type Ia supernova remnant (SNR) with two different background magnetic field(BMF) topologies:a uniform and a turbulent *** density distribution and magnetic-field characteristics of our benchmark SNR are studied with two-dimensional cylindrical magnetohydrodynamic *** γ_(eff)is considered,we find that:(1) the two-shock structure shrinks and the downstream magnetic-field orientation is dominated by the Rayleigh–Taylor instability structures;(2) there exists more quasi-radial magnetic fields inside the shocked region;and (3) inside the intershock region,both the quasi-radial magnetic energy density and the total magnetic energy density are enhanced:in the radial direction,with γ_(eff)=1.1,they are amplified about 10–26 times more than those with γ_(eff)=5/*** in the angular direction,the total magnetic energy densities could be amplified about 350 times more than those with γ_(eff)=5/3,and there are more grid cells within the intershock region where the magnetic energy density is amplified by a factor greater than 100.

关键词： methods:numerical ISM:magnetic fields ISM:supernova remnants magnetohydrodynamics(MHD)

Laparoscopic anatomical liver resection of segment 7 using a sandwich approach to the right hepatic vein (with video)

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 217-220页

作者： Song-Feng yu Wei-Chen Zhang jun yu Department of Hepatobiliary and Pancreatic Surgery the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Full laparoscopic liver resection has been performed widely since it was introduced in the early *** has been expanded from initial for partial resection of the anterolateral segments to non-restriction of area of the liver[1–3].Anatomical liver resec-tion is considered to have potential superiority than non-anatomic resection in terms of tumor prognosis,thus it is more often rec-ommended in the treatment of hepatocellular carcinoma[4,5].Recently,laparoscopic segmental liver resection according to the Couinaud classification has been widely performed due to its ad-vantages in minimal invasiveness and tumor prognosis.

关键词： resection liver hepatic

Selective adsorption of tetracycline by β-CD-immobilized sodium alginate aerogel coupled with ultrafiltration for reclaimed water

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Chinese Journal of Chemical Engineering 2024年第4期68卷 27-34页

作者： Xi Quan jun Zhang Linlin Yin Wei Zuo yu Tian State Key Laboratory of Urban Water Resource and Environment(SKLUWRE) School of EnvironmentHarbin Institute of TechnologyHarbin 150090China

In this work,a novel composite material based on β-cyclodextrin-immobilized sodium alginate aerogel(β-CD/NaAlg) was developed utilizing cross-linker of epichlorohydrin and applied as an adsorbent to remove tetracycline antibiotics from reclaimed wastewater.A series of characterizations were utilized to confirm the successful synthesis of the adsorbent and this β-CD/NaAlg presented a three-dimensional network at the nanoscale or *** optimal conditions(pH=4,t=8 h,β-CD:NaAlg=9,adsorbent dosage = 1.5 g·L-1),the maximum removal rate of β-CD/NaAlg to tetracycline was 70%.The adsorption behavior of tetracycline on β-CD/NaAlg conformed to the Freundlich isotherm model(R2=0.9977) and the pseudo-second-order kinetic model(R^(2)=0.9993).Moreover,the adsorbent still removed 55.3% of tetracycline after five ***,the adsorbent was integrated with ultrafiltration to adsorb tetracycline antibiotics from simulated reclaimed wastewater,and the removal rate of tetracycline reached 78.9% within 2 *** existence of Cr(Ⅵ) had a negligible impact on tetracycline removal,while the presence of humic acid exhibited a promoting *** possible adsorption mechanisms were also elucidated through X-ray photoelectron spectroscopy and density functional theory *** summary,β-CD/NaAlg represents an environmentally friendly,efficient,and sustainable adsorbent for removing tetracycline antibiotics from reclaimed water.

关键词： b-CD/NaAlg aerogel Covalent grafting Tetracycline antibiotics Ultrafiltration Selective adsorption Reclaimed water

Prediction and driving factors of forest fire occurrence in Jilin Province,China

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Journal of Forestry Research 2024年第1期35卷 58-71页

作者： Bo Gao Yanlong Shan Xiangyu Liu Sainan Yin Bo yu Chenxi cui Lili Cao Wildland Fire Prevention and Fighting Innovation Center of Beihua University Forestry College of Beihua University3999 Binjiang East RoadJilin City 132013People’s Republic of China

Forest fires are natural disasters that can occur suddenly and can be very damaging,burning thousands of square *** is better than suppression and prediction models of forest fire occurrence have developed from the logistic regression model,the geographical weighted logistic regression model,the Lasso regression model,the random forest model,and the support vector machine model based on historical forest fire data from 2000 to 2019 in Jilin *** models,along with a distribution map are presented in this paper to provide a theoretical basis for forest fire management in this *** studies show that the prediction accuracies of the two machine learning models are higher than those of the three generalized linear regression *** accuracies of the random forest model,the support vector machine model,geographical weighted logistic regression model,the Lasso regression model,and logistic model were 88.7%,87.7%,86.0%,85.0%and 84.6%,*** is the main factor affecting forest fires,while the impacts of topography factors,human and social-economic factors on fire occurrence were similar.

关键词： Forest fire Occurrence prediction Forest fire driving factors Generalized linear regression models Machine learning models

Single-atom alloys prepared by two-step thermal evaporation

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Nano Research 2024年第4期17卷 2808-2813页

作者： Honglin Wang Jing Li Meirong Huang Jizhe cui Zhiying Cheng Rong yu Hongwei Zhu State Key Lab of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China State Key Lab of Solid Waste Reuse for Building Materials Beijing Building Materials Academy of Science ResearchBeijing 100041China

Single-atom alloys(SAAs)have gained significant attention due to their remarkable atomic utilization efficiency,interactions between single atoms(SAs)and metal supports,and free-atom-like electronic structure of dopant *** this work,we observed the formation of SAs in pre-deposited metal particles by a two-step thermal evaporation technique,thereby establishing the first instance of discovering SAAs by thermal *** discovery of SAAs by thermal evaporation extends the range of SAAs preparation methods to include this traditional synthetic technique,which offers convenience,cost-efficiency,and *** formation mechanism of SAAs prepared using this technique was elucidated by density functional theory *** was demonstrated that thermal evaporation can be utilized to prepare SAAs with multiple SAs,further highlighting its universal applicability.

关键词： single-atom alloys thermal evaporation density functional theory

An efficient and universal protoplast-based transient gene expression system for genome editing in Brassica crops

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Horticultural Plant Journal 2024年第4期10卷 983-994页

作者： Xiaoxiao yu Jintai yu Yin Lu Wenjing Li Guanzhong Huo jun Zhang Yan Li Jianjun Zhao jun Li State Key Laboratory of North China Crop Improvement and Regulation College of Life SciencesHebei Agricultural UniversityBaodingHebei 071001China Hebei Key Laboratory of Plant Physiology and Molecular Pathology Hebei Agricultural UniversityBaodingHebei 071001China Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei Collaborative Innovation Center of Vegetable Industry in HebeiCollege of HorticultureHebei Agricultural UniversityBaodingHebei 071001China College of Modern Science and Technology Hebei Agricultural UniversityBaodingHebei 071001China Human Resource Department Hebei Agricultural UniversityBaodingHebei 071001China

Protoplast-based transient gene expression system has been widely used in plant genome editing because of its simple operation and less *** order to establish a universal protoplast-based transient transfection system for verifying activities of genome editing vectors containing targets in Brassica,we systematically optimized factors affecting protoplast isolation and transient gene *** established an efficient protoplast-based transient gene expression system(PTGE)in Chinese cabbage,achieving high protoplast yield of 4.9×10^(5)·g^(-1)FW,viability over 95%,and transfection efficiency of 76%.We showed for the first time that pretreatment of protoplasts with a hypotonic MMG could significantly enhance the transfection ***,protoplasts incubated at 37℃ for 6 min improved the transfection efficiency to 86%.We also demonstrated that PTGE worked well(more than 50%transfection efficiency)in multiple Brassica species including cabbage,Pak Choi,Chinese kale,and ***,PTGE was used for validating the activities of CRISPR/Cas9 vectors containing targets in Chinese cabbage,cabbage,and pak choi,demonstrating the broad applicability of the established PTGE for genome editing in Brassica crops.

关键词： Chinese cabbage PTGE Transfection efficiency CRISPR/Cas9

Shape estimation for a TPU-based multi-material 3D printed soft pneumatic actuator using deep learning models

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Science China(Technological Sciences) 2024年第5期67卷 1470-1481页

作者： HU yu TANG Wei QU Yang XU HuXiu KRAMARENKO yu.Elena ZOU jun State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China School of Mechanical Engineering Zhejiang UniversityHangzhou310027China Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou310027China Faculty of Physics Lomonosov Moscow State UniversityMoscow119991Russia Enikolopov Institute of Synthetic Polymeric Materials of Russian Academy of Sciences Moscow117393Russia

Real-time proprioception presents a significant challenge for soft robots due to their infinite degrees of freedom and intrinsic *** studies mostly focused on specific sensors and *** is still a lack of generalizable technologies for integrating soft sensing elements into soft actuators and mapping sensor signals to proprioception *** tackle this problem,we employed multi-material 3D printing technology to fabricate sensorized soft-bending actuators(SBAs)using plain and conductive thermoplastic polyurethane(TPU)*** designed various geometric shapes for the sensors and investigated their strain-resistive performance during *** address the nonlinear time-variant behavior of the sensors during dynamic modeling,we adopted a data-driven approach using different deep neural networks to learn the relationship between sensor signals and system states.A series of experiments in various actuation scenarios were conducted,and the results demonstrated the effectiveness of this *** sensing and shape prediction steps can run in real-time at a frequency of50 Hz on a consumer-level ***,a method is proposed to enhance the robustness of the learning models using data augmentation to handle unexpected sensor *** the methods are efficient,not only for in-plane 2D shape estimation but also for out-of-plane 3D shape *** aim of this study is to introduce a methodology for the proprioception of soft pneumatic actuators,including manufacturing and sensing modeling,that can be generalized to other soft robots.

关键词： shape estimation soft sensors and actuators 3D printing deep learning in robotics

Risk assessment of oil and gas investment environment in countries along the Belt and Road Initiative

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Petroleum Science 2024年第2期21卷 1429-1443页

作者： Bao-jun Tang Chang-Jing Ji yu-Xian Zheng Kang-Ning Liu Yi-Fei Ma jun-yu Chen Center for Energy and Environmental Policy Research Beijing Institute of TechnologyBeijing100081China School of Management and Economics Beijing Institute of TechnologyBeijing100081China Collaborative Innovation Center of Electric Vehicles in Beijing BeijingChina Sustainable Development Research Institute for Economy and Society of Beijing BeijingChina Institute of Carbon Neutrality ShanghaiTech UniversityShanghai201210China

With the implementation of the Belt and Road Initiative, China is deepening its cooperation in oil and gas resources with countries along the Initiative. In order to better mitigate risks and enhance the safety of investments, it is of significant importance to research the oil and gas investment environment in these countries for China's overseas investment macro-layout. This paper proposes an indicator system including 27 indicators from 6 dimensions. On this basis, game theory models combined with global entropy method and analytic hierarchy process are applied to determine the combined weights, and the TOPSIS-GRA model is utilized to assess the risks of oil and gas investment in 76 countries along the Initiative from 2014 to 2021. Finally, the GM(1,1) model is employed to predict risk values for 2022-2025. In conclusion, oil and gas resources and political factors have the greatest impact on investment environment risk, and 12 countries with greater investment potential are selected through cluster analysis in conjunction with the predicted results. The research findings may provide scientific decisionmaking recommendations for the Chinese government and oil enterprises to strengthen oil and gas investment cooperation with countries along the Belt and Road Initiative.

关键词： Belt and Road Initiative Oil and Gas Investment Risk assessment

Corrosion Behavior of Pre-oxidized GH4169 Alloy with Solid NaCl Deposited in a Wet Oxygen Flow at 600℃

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1249-1264页

作者： Weidong Zhang yu cui Li Liu Wenquan Wang Wenzheng Chen Rui Li Fuhui Wang Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang110819China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The corrosion behavior of the pre-oxidized GH4169 alloy was studied after 20 h of exposure under a solid NaCl deposit film in a wet O_(2) environment at 600℃by mass-gain measurements,X-ray diffraction,scanning electron microscopy,transmission electron microscopy *** results indicate that the pre-oxidized GH4169 alloy undergoes serious corrosion in the corrosive *** preformed Cr_(2)O_(3) layer is gradually destroyed by deposit NaCl,and the inner Nb2O5 layer beneath the complete outer Cr_(2)O_(3) layer also reacts with NaCl to form NaNbO_(3).The electrochemical test results testified the existence of electrochemical reactions during this corrosion *** corrosion behavior of pre-oxidized GH4169 under a solid NaCl deposit film in a wet O_(2) environment at 600℃has been discussed in detail.

关键词： Pre-oxidation Solid NaCl Wet O2 Electrochemical corrosion