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Research on the influences of motion characteristics of jetting projectile charge under water

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Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： xing chen Yong-gang Lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater *** paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in *** findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying *** the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the *** optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in *** density plays a crucial role in the velocity decay pattern of the JPC during *** with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are ***,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge ***,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

Biological factors driving colorectal cancer metastasis

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 259-272页

作者： Shuai-xing An Zhao-Jin Yu chen fu Min-Jie Wei Long-Hai Shen Department of Pharmacology School of PharmacyChina Medical UniversityShenyang 110122Liaoning ProvinceChina Liaoning Key Laboratory of Molecular Targeted Antitumor Drug Development and Evaluation Liaoning Cancer Immune Peptide Drug Engineering Technology Research CenterKey Laboratory of Precision Diagnosis and Treatment of Gastrointestinal Tumors(China Medical University)Ministry of EducationShenyang 110122Liaoning ProvinceChina BD Department Greenpine Pharma Group Co.LtdTianjin 300020China Center of Oncology Genertec Liaoyou Gem Flower HospitalPanJin 124010Liaoning ProvinceChina

Approximately 20%of colorectal cancer(CRC)patients present with metastasis at *** Stage I-III CRC patients who undergo surgical resection,18%typically suffer from distal metastasis within the first three years following initial *** median survival duration after the diagnosis of metastatic CRC(mCRC)is only 9 *** is traditionally considered to be an advanced stage malignancy or is thought to be caused by incomplete resection of tumor tissue,allowing cancer cells to spread from primary to distant organs;however,increa-sing evidence suggests that the mCRC process can begin early in tumor *** patients present with high heterogeneity and diverse cancer phenotypes that are classified on the basis of molecular and morphological *** genomic and nongenomic events can induce subclone diversity,which leads to cancer and *** the course of mCRC,metastatic cascades are associated with invasive cancer cell migration through the circulatory system,extravasation,distal seeding,dormancy,and reactivation,with each step requiring specific molecular ***,cancer cells presenting neoantigens can be recognized and eliminated by the immune *** this review,we explain the biological factors that drive CRC metastasis,namely,genomic instability,epigenetic instability,the metastatic cascade,the cancer-immunity cycle,and external lifestyle *** remarkable progress in CRC research,the role of molecular classification in therapeutic intervention remains *** review shows the driving factors of mCRC which may help in identifying potential candidate biomarkers that can improve the diagnosis and early detection of mCRC cases.

关键词： cancer Metastasis cascade Cancer immunity Genomic variation Epigenetic instability Lifestyle factor

Acetylene/argon mixture plasma to build ultrathin carbon bridge of CF_(x)/C/MnO_(2) for high-rate lithium primary battery

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Rare Metals 2024年第6期43卷 2574-2584页

作者： Da-Wei Zou xing-Guang fu Gao-Bang chen Yi-Fan Liu Bao-Shan Wu Xian Jian School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 31300lChina

Forming an ultrathin conducting layer on a fluorinated carbon(CFx)surface for reducing severe electrochemical polarization in lithium/fluorinated carbon primary batteries(Li/CF_(x))remains a considerable challenge for achieving batteries with excellent rate ***,CFxwas modified by using acetylene/argon mixture plasma combined with MnO_(2)*** CF_(x)/C/MnO_(2)composite effectively reduced the voltage hysteresis and improved the electrochemical performance of Li/CF_(x).The excellent rate performance of CF_(x)/C/MnO_(2)was due to the high electrochemical activity provided by the atomicscale conductive carbon layer and ultrafine MnO_(2)*** with pristine CF_(x),the charge transfer resistance of the optimized CF_(x)/C/MnO_(2)decreased from 218.5 to 48.2Ω,the discharge rate increased from 2C to 10C,and the power density increased from 3.11 to 13.44 kW·g^(-1),The intrinsic reason for the enhanced rate performance was attributed to the fact that the ultrathin carbon layer acted as a conductive bridge to reduce the voltage hysteresis at the initial stage of the Li/CF_(x)discharge,and the high electrochemical activity of the ultrafine MnO_(2)particles provided a faster lithium-ion diffusion rate.

关键词： C_(2)H_(2)/Ar plasma Fluorinated carbon Lithium primary battery MnO_(2)

Rogue wave solutions and rogue-breather solutions to the focusing nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 33-41页

作者： Si-Jia chen xing Lü College of Science Tianjin University of TechnologyTianjin 300384People's Republic of China Department of Mathematics Beijing Jiaotong UniversityBeijing 100044People's Republic of China Beijing Laboratory of National Economic Security Early-warning Engineering Beijing Jiaotong UniversityBeijing 100044People's Republic of China

Based on the long wave limit method,the general form of the second-order and third-order rogue wave solutions to the focusing nonlinear Schr?dinger equation are given by introducing some arbitrary *** interaction solutions between the first-order rogue wave and one-breather wave are constructed by taking a long wave limit on the two-breather *** applying the same method to the three-breather solutions,two types of interaction solutions are obtained,namely the first-order rogue wave and two breather waves,the second-order rogue wave and one-breather wave,*** influence of the parameters related to the phase on the interaction phenomena is graphically *** occur among the rogue waves and breather *** the collisions,the shape of them remains *** abundant interaction phenomena in this paper will contribute to a better understanding of the propagation and control of nonlinear waves.

关键词： nonlinear Schrodinger equation rogue wave solutions interaction solutions

Evaluation of 3D crustal seismic velocity models in southwest China:Model performance,limitation,and prospects

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Science China Earth Sciences 2024年第2期67卷 604-619页

作者： Xin WANG Ling chen Qi-fu chen Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China

Southwest China is a tectonically and seismically active region,witnessing strong deformation due to the collision between the Indian and Eurasian *** the subsurface velocity structure of this region is thus important in understanding the tectonics and geodynamic processes of continental collision and in mitigating seismic *** studies have provided various 3D seismic velocity models in southwest ***,discrepancies exist among these models,and less effort has been made to quantify the reliability and accuracy of these existing velocity *** this study,we use regional 3D waveform simulation to evaluate the performance of various regional crustal 3D velocity models in reproducing observed *** particularly focus on two recent earthquake sequence in the region,the 2021 Yunnan Yangbi MS_(6.4) earthquake sequence and the 2022 Sichuan Luding MS_(6.8) earthquake *** tested 3D velocity models include the Southwest China Community Velocity model V1.0,the Unified Seismic Tomography Models for Continental China Lithosphere V2.0,the adjoint full waveform tomography model of the crustal and upper mantle beneath Eastern Tibetan Plateau,and the shallow seismic structure model beneath continental *** results show that the tested 3D velocity models generally capture well long-period(full-waveform tomography model shows a slighter better performance than the other models,especially for the body-waves,highlighting the advantages

关键词： Southwest China Seismic tomography models Shallow Structures Waveform simulation Model evaluation

A refined representation method of the particle size distribution curve based on grading entropy

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Particuology 2024年第5期88卷 302-311页

作者： xing Li Qun chen Zhaozhao Liu cheng Zhou chen Wang chen chen State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China

The particle size distribution(PSD)curve is an important expression of the basic properties of the *** characteristic parameters such as median particle size D_(50),effective particle size D_(10),and some combinations of characteristic parameters can only represent some points of the PSD curve,failing to represent all information of the PSD *** this paper,a fraction characteristic parameter F that could reflect the fraction size variation of the PSD curve was introduced based on grading *** a new presentation method of the A-B-F three parameters was proposed for a refined representation of the PSD *** was found that the newly constructed model not only better represents the differences in the width of PSD curves but also has a higher sensitivity than the A-B two-parameter model proposed by Lő*** PSD curves with similar distributions,the new presentation method has a higher degree of discrimination than that of the D_(50)-C_(u)-C_(c) three-parameter or the four-parameter combination G_(c) proposed by ***,the application of this new method in describing the spatial nonuniformity distribution of depositions and predicting the soil hydraulic conductivity was *** research results can provide a reference for the refined representation of PSD curves.

关键词： Grading entropy Particle size distribution curve Refined representation

Study on concentration distribution and detonation characteristics for non-axisymmetric fuel dispersal

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Defence Technology（防务技术） 2024年第1期31卷 484-495页

作者： Linghui Zeng Zhongqi Wang xing chen Jianping Li State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China College of Environment and Chemical Engineering Sichuan University of Science&EngineeringZigong643000China

The study of non-axisymmetric fuel dispersal and detonation can provide reference for the prevention of industrial cloud explosion accidents and the design of fuel air explosive(FAE).The concentration and detonation fields of 85 kg cylindrical and fan-shaped fuel are investigated by experiments and numerical simulations.A dynamic model of the whole process for fuel dispersal and detonation is *** concentration distribution of fuel is used as the initial condition to calculate the detonation stage,thus solving the initial value problem of detonation *** phase and component changes of fuel cloud at different locations are *** fuel cloud is divided into directions of 0°,90°,135°and 180°.The results show that the maximum cloud radius is 20.94 m in 135°and the minimum is 12.04 m in 0°.The diameter of the detonation fireball is 53.6 m,and the peak temperature is 3455 *** highest peak overpressure is 3.44 MPa in 0°and the lowest is 2.97 MPa in 135°.The proportion of liquid phase in 0°is22.90%,and the fuel loss is 11.8% and 9% higher than that in 135°and cylindrical charge,*** stable propagation distance of blast wave in 135°is 42.50% longer than 0°and 28.37% longer than cylindrical charge.

关键词： fuel dispersal Concentration distribution Detonation characteristic fuel loss Numerical simulation

A Novel ISSA–DELM Model for Predicting Rock Mass Permeability

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2825-2848页

作者： chen xing Leihua Yao Yingdong Wang School of Engineering and Technology China University of Geosciences(Beijing)Beijing100083China Beijing Engineering Corporation Limited Beijing100024China

In pumped storage projects,the permeability of rock masses is a crucial parameter in engineering design and *** rock mass permeability coefficient(K)is influenced by various geological parameters,and previous studies aimed to establish an accurate relationship between K and geological *** study uses the improved sparrow search algorithm(ISSA)to optimize the parameter settings of the deep extreme learning machine(DELM),constructing a prediction model with flexible parameter selection and high ***,the Spearman method is applied to analyze the correlation between geological parameters.A sample database is built by comprehensively selecting four geological indexes:burial depth,rock quality designation(RQD),fracture density characteristic index(FD),and rock mass integrity designation(RID).Hence,the defects of the sparrow search algorithm(SSA)are enhanced using the improved strategy,and the initial input weights of the DELM are ***,the proposed ISSA–DELM model is employed to predict the permeability coefficient of rock mass in the entire study *** results showed that the predictive performance of the model is superior to that of the DELM and SSA–***,this model successfully provides insights into the distribution characteristics of rock mass permeability at engineering sites.

关键词： ISSA DELM rock mass permeability coefficient geological parameter correlation analysis

Experimental investigation of spectral evolution in flash radiation by hypervelocity impact on aluminum plates

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Defence Technology（防务技术） 2024年第7期37卷 96-110页

作者： xing chen Yonggang Lu Zhiwen Li Zhonghua Cui Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina Chongqing Qianwei Technology Group Co. LtdChongqing 401121China

In this study,a series of hypervelocity impact tests were carried out based on a two-stage light gas gun,and the sequence spectrum and radiation evolution data of the impact products under different impact conditions were *** diameter of the projectile is 3-5 mm,the impact velocity is 3.13-6.58 km/s,and the chamber pressure is 0.56-990 *** spectrum of ejected debris cloud in the 250-310 nm band were obtained using a transient spectral measurement system and a multi-channel radiometer measurement *** test results reveal that the flash radiation intensity increases as a power function with the kinetic energy of the ***,the peak value of the line spectrum decreases as the chamber vacuum degree increases,while the radiation width gradually *** line spectrum in the spectral characterization curve corresponds to the ejected debris clouds splitting phase,which does not produce significant line spectrum during material fragmentation and is dominated by the continuum spectrum produced by blackbody *** will appear one or three characteristic peaks in the flash radiation time curve,the first and second peaks correspond to the penetration phase and the third peak corresponds to the expansion phase of the ejected debris clouds on the time scale,the first and second peaks are more sensitive to the chamber vacuum degree,and when the pressure is higher than 99 Pa,the first and second characteristic peaks will *** radiant heat attenuation of the flash under different impact conditions is significantly different,the attenuation exponent has a power function relationship with the impact velocity and the chamber vacuum degree,while the attenuation exponent has a linear relationship with the diameter of the projectile,the specific expression of the attenuation exponent is obtained by *** findings from this research can serve as a valuable reference for remote diagnostic technologies based on flash radiation characte

关键词： Hypervelocity impact Flash radiation Evolution Spectral characteristics Damage evaluation