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Experimental research on the launching system of auxiliary charge with filter cartridge structure

Defence Technology（防务技术） 2024年第1期31卷 41-48页

作者： Zi-jun Chen Ze He hong-Hao Ma Lu-Qing Wang zhao-Wu Shen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefeiAnhui230027PR China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefeiAnhui230026PR China

A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the projectile.The combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the barrel.The breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the projectile.In this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the projectile.The proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the chamber.In order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are discussed.The experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak pressure.The projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,respectively.The muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the barrel.Under the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%.

关键词： Interior ballistics Charge structures Launch system Charge design

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High-entropy oxide-supported platinum nanoparticles for efficient hydrogen evolution reaction

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Rare Metals 2024年第4期43卷 1537-1546页

作者： Ming-Yu Fan Jia-jun Wang jun zhao hong Zhang Tian-Yi Ma Xiao-Peng Han Wen-Bin Hu School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional Materials Key Laboratory of Advanced Ceramics and Machining Technology Tianjin University School of National University of Singapore and Tianjin University International Campus of Tianjin University School of Science RMIT University

High-entropy oxides（HEOs） are a new class of single-phase structures with unique electronic and catalytic properties;therefore,it is worthwhile to explore their applications in electrocatalysis.In this study,a Pt/（FeCoNiCrAl）3O4nanohybrid using HEO as a support was developed as an efficient catalyst for the hydrogen evolution reaction（HER）.Pt/（FeCoNiCrAl）3O4exhibited high HER activity with a low overpotential of 22 mV at10 mA·cm-2,outperforming other binary,ternary,and quaternary supports.The HER activity of Pt/（FeCoNiCrAl）3O4was higher than that of a commercial Pt/C with a significantly lower Pt loading.The catalyst exhibited good activity and long-term stability（60 h） in an electrolytic water-splitting device.This good activity can be attributed to the fact that the introduction of Pt effectively facilitates electronic interactions between Pt and the HEO.In addition,the HEO substrate was more favorable for dispersing Pt particles,optimizing the electrochemical specific surface area,and significantly reducing the charge resistance of the HER.This study extends the application of HEOs in electrocatalysis and demonstrates the promising prospects of HEOs as supports for electrocatalysts.

关键词： High-entropy oxides Hydrogen evolution reaction Nanohybrid Water electrolysis

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Angiosperm-wide analysis of fruit and ovary evolution aided by a new nuclear phylogeny supports association of the same ovary type with both dry and fleshy fruits

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Journal of Integrative Plant Biology 2024年第2期66卷 228-251页

作者： Yezi Xiang Taikui Zhang Yiyong zhao hongjin Dong hongyi Chen Yi Hu Chien-Hsun Huang jun Xiang hong Ma State Key Laboratory of Genetic Engineering Ministry of Education Key Laboratory of Biodiversity and Ecological EngineeringInstitute of Plant BiologyCenter of Evolutionary BiologySchool of Life SciencesFudan UniversityShanghai 200438China Department of Biology Howard Hughes Medical InstituteDuke UniversityDurhamNC 27708USA Department of Biology the Eberly College of Scienceand the Huck Institutes of the Life Sciencesthe Pennsylvania State UniversityUniversity ParkPA 16802USA Hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization College of Biology and Agricultural ResourcesHuanggang Normal UniversityHuanggang 438000China

Fruit functions in seed protection and dispersal and belongs to many dry and fleshy types,yet their evolutionary pattern remains unclear in part due to uncertainties in the phylogenetic relationships among several orders and families.Thus we used nuclear genes of 502 angiosperm species representing 231 families to reconstruct a well supported phylogeny,with resolved relationships for orders and families with previously uncertain placements.Using this phylogeny as a framework,molecular dating supports a Triassic origin of the crown angiosperms,followed by the emergence of most orders in the Jurassic and Cretaceous and their rise to ecological dominance during the Cretaceous Terrestrial Revolution.The robust phylogeny allowed an examination of the evolutionary pattern of fruit and ovary types,revealing a trend of parallel carpel fusions during early diversifications in eudicots,monocots,and magnoliids.Moreover,taxa in the same order or family with the same ovary type can develop either dry or fleshy fruits with strong correlations between specific types of dry and fleshy fruits;such associations of ovary,dry and fleshy fruits define several ovaryfruit"modules"each found in multiple families.One of the frequent modules has an ovary containing multiple ovules,capsules and berries,and another with an ovary having one or two ovules,achenes(or other single-seeded dry fruits)and drupes.This new perspective of relationships among fruit types highlights the closeness of specific dry and fleshy fruit types,such as capsule and berry,that develop from the same ovary type and belong to the same module relative to dry and fleshy fruits of other modules(such as achenes and drupes).Further analyses of gene families containing known genes for ovary and fruit development identified phylogenetic nodes with multiple gene duplications,supporting a possible role of whole-genome duplications,in combination with climate changes and animal behaviors,in angiosperm fruit and ovary diversification.

关键词： angiosperm fruit evolution MADS-box molecular clock nuclear phylogeny ovary and fruit developmental genes

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Degradation of warm permafrost and talik formation on the Qinghai-Tibet Plateau in 2006-2021

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Advances in Climate Change Research 2024年第2期15卷 275-284页

作者： Qi-Hang MEI Ji CHEN You-Qian LIU Shou-hong ZHANG Jing-Yi zhao Tian-Chun DONG jun-Cheng WANG Yao-jun zhao Beiluhe Observation and Research Station of Frozen Soil Engineering and Environment Key Laboratory of Cryospheric Science and Frozen Soil EngineeringNorthwest Institute of Eco-Environmental and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway Qinghai-Tibet Group Co.Ltd Xining 810007China University of Chinese Academy of Sciences Beijing 100049China

Permafrost is degrading globally,particularly those with low thermal stability on the Qinghai-Tibet Plateau,owing to climate change.However,the inadequacy of direct research on permafrost degradation based on in-situ monitoring limits the prediction of permafrost degradation and engineering practices.This study explored the processes and modes of permafrost degradation into talik by analyzing ground temperature data from five points in the hinterland of the Qinghai-Tibet Plateau from 2006 to 2021.The results showed that the degradation of the warm permafrost layer with a geothermal gradient of zero occurred simultaneously in the top and bottom directions.The rate of permafrost degradation from the top down and bottom up increase during the degradation process,but the increase of the former is more drastic after the formation of thawed interlayer.Additionally,the construction of the Qinghai-Tibet Railway changed the degradation modes of the permafrost in adjacent natural sites through horizontal heat transfer,particularly after through talik formation under the embankment.The findings suggest that taking countermeasures before or immediately after forming thawed interlayer is more effective.When evaluating the thermal impact of projects in warm permafrost regions,special attention should be given to the horizontal heat transfer process that may result from the formation of a through talik.

关键词： Warm permafrost Degradation Talik Qinghai-Tibet Plateau Climate change

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A novel small-signal equivalent circuit model for GaN HEMTs incorporating a dual-field-plate

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Journal of Semiconductors 2024年第5期45卷 61-68页

作者： Jinye Wang jun Liu Zhenxin zhao School of Integrated Circuit Science and Engineering Hangzhou Dianzi UniversityHangzhou 310018China

An accurate and novel small-signal equivalent circuit model for GaN high-electron-mobility transistors(HEMTs)is proposed,which considers a dual-field-plate(FP)made up of a gate-FP and a source-FP.The equivalent circuit of the overall model is composed of parasitic elements,intrinsic transistors,gate-FP,and source-FP networks.The equivalent circuit of the gate-FP is identical to that of the intrinsic transistor.In order to simplify the complexity of the model,a series combination of a resistor and a capacitor is employed to represent the source-FP.The analytical extraction procedure of the model parameters is presented based on the proposed equivalent circuit.The verification is carried out on a 4×250μm GaN HEMT device with a gate-FP and a source-FP in a 0.45μm technology.Compared with the classic model,the proposed novel small-signal model shows closer agreement with measured S-parameters in the range of 1.0 to 18.0 GHz.

关键词： small-signal model dual field-plate(FP) GaN high-electron-mobility transistors(HEMT) parameter extraction

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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 loops.The 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 improved.However,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 temperature.Defect is one of the causes of space charge phenomenon,resulting in the increase in dielectric constant.Moreover,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

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Effect of Wave Nonlinearity on the Instantaneous Seabed Liquefaction

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China Ocean Engineering 2024年第1期38卷 93-103页

作者： WANG zhao-jun SUI Ti-ti ZHANG Chi PAN jun-ning Key Laboratory of Port Waterway and Sedimentation Engineering of the Ministry of TransportNanjing Hydraulic Research InstituteNanjing 210024China Key Laboratory of Coastal Disaster and Protection(Hohai University) Ministry of EducationNanjing 210098China The National Key Laboratory of Water Disaster Prevention Nanjing 210098China

The nonlinear variation of wave is commonly seen in nearshore area,and the resulting seabed response and liquefaction are of high concern to coastal engineers.In this study,an analytical formula considering the nonlinear wave skewness and asymmetry is adopted to provide wave pressure on the seabed surface.The liquefaction depth attenuation coefficient and width growth coefficient are defined to quantitatively characterize the nonlinear effect of wave on seabed liquefaction.Based on the 2D full dynamic model of wave-induced seabed response,a detailed parametric study is carried out in order to evaluate the influence of the nonlinear variation of wave loadings on seabed liquefaction.Further,new empirical prediction formulas are proposed to fast predict the maximum liquefaction under nonlinear wave.Results indicate that(1)Due to the influence of wave nonlinearity,the vertical transmission of negative pore water pressure in the seabed is hindered,and therefore,the amplitude decreases significantly.(2)In general,with the increase of wave nonlinearity,the liquefaction depth of seabed decreases gradually.Especially under asymmetric and skewed wave loading,the attenuation of maximum seabed liquefaction depth is the most significant among all the nonlinear wave conditions.However,highly skewed wave can cause the liquefaction depth of seabed greater than that under linear wave.(3)The asymmetry of wave pressure leads to the increase of liquefaction width,whereas the influence of skewedness is not significant.(4)Compared with the nonlinear waveform,seabed liquefaction is more sensitive to the variation of nonlinear degree of wave loading.

关键词： nonlinear wave seabed response seabed liquefaction numerical simulation liquefaction prediction

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PRaG 3.0 therapy for human epidermal growth factor receptor 2-positive metastatic pancreatic ductal adenocarcinoma:A case report

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World Journal of Gastroenterology 2024年第9期30卷 1237-1249页

作者： Yue-hong Kong Mei-Ling Xu jun-jun Zhang Guang-Qiang Chen Zhi-Hui hong hong Zhang Xiao-Xiao Dai Yi-Fu Ma Xiang-Rong zhao Chen-Yang Zhang Rong-Zheng Chen Peng-Fei Xing Li-Yuan Zhang Center for Cancer Diagnosis and Treatment The Second Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina Department of Radiotherapy&Oncology The Second Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina Institution of Radiotherapy&Oncology Soochow UniversitySuzhou 215000Jiangsu ProvinceChina Department of Radiology The Second Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina Department of Nuclear Medicine The Second Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina Department of Clinical Laboratory The Second Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina Department of Pathology The Second Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina

BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)is a highly fatal disease with limited effective treatment especially after first-line chemotherapy.The human epidermal growth factor receptor 2(HER-2)immunohistochemistry(IHC)positive is associated with more aggressive clinical behavior and shorter overall survival in PDAC.CASE SUMMARY We present a case of multiple metastatic PDAC with IHC mismatch repair proficient but HER-2 IHC weakly positive at diagnosis that didn’t have tumor regression after first-line nab-paclitaxel plus gemcitabine and PD-1 inhibitor treatment.A novel combination therapy PRaG 3.0 of RC48(HER2-antibody-drug conjugate),radio-therapy,PD-1 inhibitor,granulocyte-macrophage colony-stimulating factor and interleukin-2 was then applied as second-line therapy and the patient had confirmed good partial response with progress-free-survival of 6.5 months and overall survival of 14.2 month.She had not developed any grade 2 or above treatment-related adverse events at any point.Percentage of peripheral CD8^(+) Temra and CD4^(+) Temra were increased during first two activation cycles of PRaG 3.0 treatment containing radiotherapy but deceased to the baseline during the maintenance cycles containing no radiotherapy.CONCLUSION PRaG 3.0 might be a novel strategy for HER2-positive metastatic PDAC patients who failed from previous first-line approach and even PD-1 immunotherapy but needs more data in prospective trials.

关键词： Pancreatic ductal adenocarcinoma PRaG 3.0 therapy Human epidermal growth factor receptor 2 Novel combination therapy Case report

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Self-Triggered Set Stabilization of Boolean Control Networks and Its Applications

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1631-1642页

作者： Rong zhao jun-e Feng Dawei Zhang the School of Mathematics Shandong UniversityShandong UniversityJinan 250100China

Set stabilization is one of the essential problems in engineering systems, and self-triggered control(STC) can save the storage space for interactive information, and can be successfully applied in networked control systems with limited communication resources. In this study, the set stabilization problem and STC design of Boolean control networks are investigated via the semi-tensor product technique. On the one hand, the largest control invariant subset is calculated in terms of the strongly connected components of the state transition graph, by which a graph-theoretical condition for set stabilization is derived. On the other hand, a characteristic function is exploited to determine the triggering mechanism and feasible controls. Based on this, the minimum-time and minimum-triggering open-loop, state-feedback and output-feedback STCs for set stabilization are designed,respectively. As classic applications of self-triggered set stabilization, self-triggered synchronization, self-triggered output tracking and self-triggered output regulation are discussed as well. Additionally, several practical examples are given to illustrate the effectiveness of theoretical results.

关键词： Boolean control networks(BCNs) output regulation self-triggered control semi-tensor product of matrices set stabilization synchronization

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Passivity-Based Stabilization for Switched Stochastic Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1307-1309页

作者： Yaowei Sun jun zhao School of Automation Zhengzhou University of AeronauticsZhengzhou 450046 Henan Key Laboratory of General Aviation Technology Zhengzhou University of AeronauticsZhengzhou 450046China College of Information Science and Engineering Northeastern UniversityShenyang 110819China

Dear Editor,This letter addresses the passivity-based mean square exponential stabilization problem for switched stochastic nonlinear systems.A concept of generalized small-time norm-observability is presented and an appropriate test condition is also provided.For pre-given passivity rate and average dwell time,a set of feedback controllers is designed by use of the passivity property.

关键词： property letter stabilization

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