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A Simplified Method for the Stress Analysis of Underground Transfer Structures Crossing Multiple Subway Tunnels

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2893-2915页

作者： Shen Yan Dajiang geng Ning Dai Mingjian long Zhicheng Bai College of Civil Engineering Tongji UniversityShanghai200092China China Construction 4th Engineering Bureau 6th Corp. Ltd.Shanghai201199China Department of Civil and Architecture Engineering Hubei Polytechnic UniversityHuangshi435003China

According to the design specifications,the construction of extended piles involves traversing the tunnel’s upper region and extending to the underlying rock layer.To address this challenge,a subterranean transfer structure spanning multiple subway tunnels was proposed.Deliberating on the function of piles in the transfer structure as springs with axial and bending stiffness,and taking into account the force balance and deformation coordination conditions of beams and plates within the transfer structure,we established a simplified mechanical model that incorporates soil stratification by combining it with the Winkler elastic foundation beam model.The resolved established simplifiedmechanicalmodel employed finite difference technology and the Newton-Simpsonmethod,elucidating the mechanical mechanism of the transfer structure.The research findings suggest that the load carried by the upper structural columns can be transferred to the pile foundation beneath the beams through the transfer structure,subsequently reaching the deep soil layer and ensuring minimal impact on adjacent tunnels.The established simplified analysis method can be used for stress analysis of the transfer structure,concurrently considering soil stratification,pile foundation behavior,and plate action.The pile length,pile section size,and beam section size within the transfer structure should account for the characteristics of the upper load,ensuring an even distribution of the beam bending moment.

关键词： Crossing tunnels transfer structure force mechanism simplify analysis layered soil mass

Enemies atpeace:Recentprogressin Agrobacterium-mediated cereal transformation

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The Crop Journal 2024年第2期12卷 321-329页

作者： Shaoshuai Liu Ke Wang Shuaifeng geng Moammar Hossain Xingguo Ye Aili Li long Mao Karl-Heinz Kogel State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Institute of Phytopathology Centre for BioSystemsLand Use and NutritionJustus Liebig UniversityHeinrich Buff-Ring 26-32D-35392GiessenGermany

Agrobacterium tumefaciens mediated plant transformation is a versatile tool for plant genetic engineering following its discovery nearly half a century ago.Numerous modifications were made in its application to increase efficiency,especially in the recalcitrant major cereals plants.Recent breakthroughs in transformation efficiency continue its role as a mainstream technique in CRISPR/Cas-based genome editing and gene stacking.These modifications led to higher transformation frequency and lower but more stable transgene copies with the capability to revolutionize modern agriculture.In this review,we provide a brief overview of the history of Agrobacterium-mediated plant transformation and focus on the most recent progress to improve the system in both the Agrobacterium and the host recipient.A promising future for transformation in biotechnology and agriculture is predicted.

关键词： Agrobacterium tumefaciens Cereal species Genome editing Genetic engineering Plant breeding

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The effects of in ovo feeding of selenized glucose on liver selenium concentration and antioxidant capacity in neonatal broilers

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Chinese Chemical Letters 2024年第6期35卷 312-315页

作者： Jiahui Li Qiao Shi Ying Xue Mingde Zheng long Liu Tuoyu geng Daoqing Gong Minmeng Zhao Jiangsu Key Laboratory of Animal genetic Breeding and Molecular Design College of Animal Science and TechnologyYangzhou UniversityYangzhou 225009China Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China Yangzhou UniversityYangzhou 225009China

Selenium is an essential trace element for humans and animals.As the active center of selenoproteins,the addition of selenium is beneficial to enhance the antioxidant ability.However,the high cost limits the application of organic Se in agriculture animal production.Selenized glucose(SeGlu)is a newly invented organoselenium material with good stability,low toxicity and low cost.This assay found that SeGlu was able to increase selenium deposition in liver of newborn broilers,and enhance the antioxidant capacity of liver by elevating the activities of antioxidant enzymes such as total superoxide dismutase and glutathione peroxidase.This paper as the first example clarifying the mechanism of SeGlu to enhance the antioxidant ability of chicks,shows that SeGlu can be used as an organic selenium enrichment additive for early nutrition of poultry.As a cross-discipline study involving chemistry,biology and agriculture animal science,the work may be beneficial for studies in related fields and prompt the development of the selenium science.

关键词： Selenized glucose In ovo feeding Antioxidant capacity Selenium Broiler

Concurrent hetero-/homo-geneous electrocatalysts to bi-phasically mediate sulfur species for lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第6期93卷 663-668,I0016页

作者： Rui-Bo LingHu Jin-Xiu Chen Jin-Hao Zhang Bo-Quan Li Qing-Shan Fu Gulnur Kalimuldina geng-Zhi Sun Yunhu Han long Kong Xi’an Institute of Flexible Electronics(IFE) Northwestern Polytechnical UniversityXi’an 710129ShaanxiChina Institute of Advanced Materials Nanjing Tech UniversityNanjing 211816JiangsuChina Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Department of Mechanical and Aerospace Engineering School of Engineering and Digital SciencesNazarbayev UniversityKabanbay Batyr Ave.53Astana 010000Kazakhstan

Expediting redox kinetics of sulfur species on conductive scaffolds with limited charge accessible surface is considered as an imperative approach to realize energy-dense and power-intensive lithium-sulfur(Li-S)batteries.In this work,the concept of concurrent hetero-/homo-geneous electrocatalysts is proposed to simultaneously mediate liquid-solid conversion of lithium polysulfides(LiPSs)and solid lithium disulfide/sulfide(Li_(2)S_(2)/Li_(2)S)propagation,the latter of which suffers from sluggish reduction kinetics due to buried conductive scaffold surface by extensive deposition of Li_(2)S_(2)/Li_(2)S.The selected model material to verify this concept is a two-in-one catalyst:carbon nanotube(CNT)scaffold supported iron-cobalt(Fe-Co)alloy nanoparticles and partially carbonized selenium(C-Se)component.The Fe-Co alloy serves as a heterogeneous electrocatalyst to seed Li_(2)S_(2)/Li_(2)S through sulphifilic active sites,while the C-Se sustainably releases soluble lithium polyselenides and functions as a homogeneous electrocatalyst to propagate Li_(2)S_(2)/Li_(2)S via solution pathways.Such bi-phasic mediation of the sulfur species benefits reduction kinetics of LiPS conversion,especially for the massive Li_(2)S_(2)/Li_(2)S growth scenario by affording an additional solution directed route in case of conductive surface being largely buried.This strategy endows the Li-S batteries with improved cycling stability(836 mA h g^(-1)after 180 cycles),rate capability(547 mA h g^(-1)at 4 C)and high sulfur loading superiority(2.96 mA h cm^(-2)at 2.4 mg cm^(-2)).This work hopes to enlighten the employment of bi-phasic electrocatalysts to dictate liquid-solid transformation of intermediates for conversion chemistry batteries.

关键词： Lithium-sulfur batteries Electrocatalysis Lithium polysulfides Sulfur cathode Energy density

Omics-imaging signature-based nomogram to predict the progression-free survival of patients with hepatocellular carcinoma after transcatheter arterial chemoembolization

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World Journal of Clinical Cases 2024年第18期12卷 3340-3350页

作者： Qing-long Guan Hai-Xiao Zhang Jun-Peng Gu geng-Fei Cao Wei-Xin Ren Department of Interventional Radiology The First Affiliated Hospital of Xinjiang Medical UniversityUrumqi 830011Xinjiang Uygur Autonomous regionChina Department of Interventional Radiology The First Affiliated Hospital of Xinjiang Medical UniversityUrumqi 830011Xinjiang Uygur Autonomous RegionChina

BACKGROUND Enhanced magnetic resonance imaging(MRI)is widely used in the diagnosis,treatment and prognosis of hepatocellular carcinoma(HCC),but it can not effectively reflect the heterogeneity within the tumor and evaluate the effect after treatment.Preoperative imaging analysis of voxel changes can effectively reflect the internal heterogeneity of the tumor and evaluate the progression-free survival(PFS).AIM To predict the PFS of patients with HCC before operation by building a model with enhanced MRI images.METHODS Delineate the regions of interest(ROI)in arterial phase,portal venous phase and delayed phase of enhanced MRI.After extracting the combinatorial features of ROI,the features are fused to obtain deep learning radiomics(DLR)_Sig.Delong's test was used to evaluate the diagnostic performance of different typological features.K-M analysis was applied to assess PFS in different risk groups,and the discriminative ability of the model was evaluated using the Cindex.RESULTS Tumor diameter and diolame were independent factors influencing the prognosis of PFS.Delong's test revealed multi-phase combined radiomic features had significantly greater area under the curve values than did those of the individual phases(P<0.05).In deep transfer learning(DTL)and DLR,significant differences were observed between the multi-phase and individual phases feature sets(P<0.05).K-M survival analysis revealed a median survival time of high risk group and low risk group was 12.8 and 14.2 months,respectively,and the predicted probabilities of 6 months,1 year and 2 years were 92%,60%,40%and 98%,90%,73%,respectively.The C-index was 0.764,indicating relatively good consistency between the predicted and observed results.DTL and DLR have higher predictive value for 2-year PFS in nomogram.CONCLUSION Based on the multi-temporal characteristics of enhanced MRI and the constructed Nomograph,it provides a new strategy for predicting the PFS of transarterial chemoembolization treatment of HCC.

关键词： Magnetic resonance imaging Radiomics Deep learning Progression-free survival Transcatheter arterial chemoembolization Hepatocellular carcinoma

Identifying drivers of urban landuse changes in the Wenchuan earthquake- affected area by using night-time light data

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Journal of Mountain Science 2024年第4期21卷 1140-1159页

作者： HUANG Tao DING Mingtao geng Dongxian GAO Zemin ZHENG Hao School of Civil Engineering and Architecture Southwest University of Science and TechnologyMianyang 621010China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Analysis and Test Center of Sichuan Province Chengdu 610023China

To learn the process of urban land evolution before and after an earthquake is vital to formulate the urban reconstruction control policies and recovery measures in the earthquake-stricken areas.However,spatiotemporal evolution and its driving factors of urban land in earthquake-prone areas remains limited due to the scarcity of ground observation data.This research,leveraging night-time light remote sensing imagery and land cover data,conducted a comprehensive analysis of the long-term evolution characteristics of urban land in earthquake-prone areas.It introduced methodologies for assessing the socio-economic impact and the primary natural environmental factors driving urban land evolution in these regions.To validate the proposed methods,the 2008 Wenchuan earthquake-affected area in China was selected as a representative study area.The results indicated that the average Digital Number(DN)values in socio-economically impacted areas showed a trend of rising,falling,and then rising again after the earthquake.DN values in three types of damaged areas including Type Ⅱ,Type Ⅲ,and Type Ⅳ exceeded pre-earthquake levels.The analysis of determinative factors influencing urban land evolution revealed that slope and elevation were key elements in controlling urban land expansion before the earthquake,whereas factors such as slope,elevation,lithology,and faults had a stronger influence on urban land expansion after the earthquake.It can be seen that,in view of the differences in the natural conditions of regions for post-disaster reconstruction,the local government need to actively adjust and adapt to urban spatial planning,so as to leverage the scale effect of large-scale inputs of funds,facilities,human resources and other factors after the disaster,thus enhancing resilience and recovery efficiency in response to disaster impacts.

关键词： Wenchuan earthquake Night-time lights Urban land Post-earthquake reconstruction

Study on the dynamic mechanical properties of winding-block axial structure considering short circuit strain rate effect

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High Voltage 2024年第2期9卷 380-390页

作者： Xinyu Wang Ping Wang Jianghai geng Zikang Zhang Fangcheng Lü Shuguo Gao Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense North China Electric Power UniversityBaodingChina State Grid Hebei Electric Power Research Institute ShijiazhuangChina

Transformers may suffer multiple short-circuit impacts during long-term operation,and axial instability is one of the typical types of serious accidents caused by short-circuit faults.The axial instability form of the winding-block structure is analysed,and the dynamic solution of the winding short-circuit electromagnetic force is obtained by estab-lishing the three-dimensional magnetic-circuit-force multi-physical field coupling simulation model.The influence of strain rate on the cushion block constitutive equation is corrected,and the modified model is verified by short-circuit impact test and quasi-static test.The research results show that for 110 kV 31.5 MVA transformers,the maximum electromagnetic axial resultant force of winding is 363.16 kN,and the ultimate tilt force is 1214.2 kN.The pre-tightening force configuration is accordingly recom-mended to range from 363.16 to 608.28 kN,which is narrowed by 18.49%compared with the static calculation method;Meanwhile,adding a logarithmic strain rate correction term to the classical constitutive equation of the cushion block can achieve a good correction of the stress-strain relationship with the coefficient of determination above 0.99,and the cushion block has a larger elastic modulus under high strain rate load.The research results provide an important theoretical reference for the axial stability structure of transformers.

关键词： axial correction structure

Recent progress in single crystal perovskite X-ray detectors

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Science China(Information Sciences) 2024年第3期67卷 5-19页

作者： Xiao LIU Jun REN Yu-Ang CHEN Xiangshun geng Dan XIE Tian-Ling REN Tsinghua University Beijing National Research Center for Information Science and Technology (BNRist) School of Integrated Circuits

Perovskites have attracted extensive attention as radiation detection material due to their long carrier diffusion length and lifetime, high absorption coefficient, and flexible manufacturing process. Compared with polycrystalline structures, single crystal perovskites improve the performance of optoelectronic devices due to their low defect state density, better photoelectric characteristics, and chemical stability.Herein, we review the recent progress of single crystal perovskite X-ray detectors. First, we briefly introduced the basic concepts, detection mechanisms, figure of merits of perovskite X-ray detectors, and the preparation methods of single crystal perovskites. Then, we summarized the significant advancements in single crystal perovskite X-ray detectors in recent times. Finally, we discussed the critical challenges and some practicable solutions for developing high-performance X-ray detectors.

关键词： single crystal perovskites carrier transport radiation detection X-ray detectors X-ray imaging

On the thermodynamics of plasticity during quasi-isentropic compression of metallic glass

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Matter and Radiation at Extremes 2024年第2期9卷 74-89页

作者： Kaiguo Chen Bo Chen Yinan Cui Yuying Yu Jidong Yu Huayun geng Dongdong Kang Jianhua Wu Yao Shen Jiayu Dai College of Science National University of Defense TechnologyChangsha 410073People’s Republic of China Hunan Key Laboratory of Extreme Matter and Applications National University of Defense TechnologyChangsha 410073People’s Republic of China Applied Mechanics Laboratory Department of Engineering MechanicsSchool of AerospaceTsinghua UniversityBeijing 100084People’s Republic of China Institute of Fluid Physics China Academy of Engineering PhysicsMianyangPeople’s Republic of China Department of Material Science and Technology Shanghai Jiao Tong UniversityShanghaiPeople’s Republic of China

Entropy production in quasi-isentropic compression (QIC) is critically important for understanding the properties of materials under extremeconditions. However, the origin and accurate quantification of entropy in this situation remain long-standing challenges. In this work, a framework is established for the quantification of entropy production and partition, and their relation to microstructural change in QIC. Cu50Zr50is taken as a model material, and its compression is simulated by molecular dynamics. On the basis of atomistic simulation-informed physicalproperties and free energy, the thermodynamic path is recovered, and the entropy production and its relation to microstructural change aresuccessfully quantified by the proposed framework. Contrary to intuition, entropy production during QIC of metallic glasses is relativelyinsensitive to the strain rate ˙γ when ˙γ ranges from 7.5 × 10^(8) to 2 × 10^(9)/s, which are values reachable in QIC experiments, with a magnitudeof the order of 10^(−2)kB/atom per GPa. However, when ˙γ is extremely high (>2 × 10^(9)/s), a notable increase in entropy production rate with˙γ is observed. The Taylor–Quinney factor is found to vary with strain but not with strain rate in the simulated regime. It is demonstrated thatentropy production is dominated by the configurational part, compared with the vibrational part. In the rate-insensitive regime, the increase inconfigurational entropy exhibits a linear relation to the Shannon-entropic quantification of microstructural change, and a stretched exponential relation to the Taylor–Quinney factor. The quantification of entropy is expected to provide thermodynamic insights into the fundamentalrelation between microstructure evolution and plastic dissipation.

关键词： entropy metallic regime