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Effect of Plant Roots on Penetrability and Anti-Scouri-bility of Red Soil Derived from Granite 被引量:19
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作者 WUWEIDONG ZHENGSHIZHANG 《Pedosphere》 SCIE CAS CSCD 2000年第2期183-188,共6页
Distribution of plant roots in a red soil derived from granite was investigated to study the effect of plantroots on intensifying soil penetrability and anti-scouribility by the double-cutting-ring and the undisturbed... Distribution of plant roots in a red soil derived from granite was investigated to study the effect of plantroots on intensifying soil penetrability and anti-scouribility by the double-cutting-ring and the undisturbedsoil-flume methods, respectively. The plant roots system consisting mostly of fibrils, < 1 mm in diameter,was mainly distributed in the upper surface soil 30 cm in depth. It can remarhably increase the penetrabilityand anti-scouribility of the red soil derived from granite. When the root density was > 0.35 root cm-2, theintensifying effect of roots on both the penetrability and the anti-scouribility could be described by exponentequations, △ Ks = 0.0021RD1.4826 (R2 = 0.9313) and △ As = 0.0003RD1.8478 (R2 = O.9619), where △ Ks isthe value of intensified soil penetrability, a As the value of intensified soil anti-scouribility and RD the rootdensity, especially in the top soils within 30 cm in depth where plant roots were conceotrated. 展开更多
关键词 anti-scouribility GRANITE penetrability plant roots red soil
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Topically applied hypericin exhibits skin penetrability on nude mice
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作者 Zhuo-heng LI Yuan-yuan LI +1 位作者 Lai-chun LU Xiao-yu XU 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2017年第10期1020-1020,共1页
OBJECTIVE Hypericin,a powerful naturally photosensitizer in photodynamic therapy(PDT),is suitable for treating skin diseases involving excess capillary proliferation.In the present study,we aimed to evaluate the skin ... OBJECTIVE Hypericin,a powerful naturally photosensitizer in photodynamic therapy(PDT),is suitable for treating skin diseases involving excess capillary proliferation.In the present study,we aimed to evaluate the skin penetrability of a topically applied hypericin,expecting reducing the risk of prolonged skin photosensitivity,which often occurs after systemic administration.METHODS The Franz diffusion cell assay was performed to evaluate different penetration enhancers.In vivo studies,fluorescence microscopy was performed to examine the distribution of hypericin in the skin,macroscopic and microscopic analyses were also carried out to detect pathological changes in the skin after topical hypericin-PDT treatment.Immunohistochemistry was used to determine the expression of PECAM-1 in the treated skin.RESULTS 5% menthol facilitated hypericin penetrate the skin of nude mice most.The results of in vivo assays revealed that hypericin penetrated nude mice skin,spread to the dermis,and resulted in obvious photosensitivity reaction on the dermal capillaries.Moreover,skin injured by the photosensitive reaction induced by hypericin was replaced by normal skin 7 d after hypericin-PDT treatment.CONCLUSION Topical hypericin could penetrate nude mouse skin well and be great potential in PDT treatment of skin diseases. 展开更多
关键词 HYPERICIN PHOTOSENSITIZER skin penetrability photodynamic therapy
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Release Kinetics of Urea from Polymer Coated Urea and Its Relationship with Coating Penetrability
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作者 ZHANG Hai-jun, WU Zhi-jie, CHEN Li-jun and LIANG Wen-ju(Institute of Applied Ecology , Chinese Academy of Sciences , Shenyang 110016 , P. R. China) 《Agricultural Sciences in China》 CAS CSCD 2003年第11期1232-1238,共7页
Four kinds of polymer coated urea(PCU)were put in distilled water at 30℃ to determine the variation of coating penetrability and give a precise description of the urea release kinetics. The urea release from PCU coul... Four kinds of polymer coated urea(PCU)were put in distilled water at 30℃ to determine the variation of coating penetrability and give a precise description of the urea release kinetics. The urea release from PCU could be divided into four stages: lag stage, swell stage, steady stage and decay stage. The release rate coefficient K, a measure of coating penetrability, was linearly increased at swell stage, but almost not variable at steady stage. At decay stage, the relation of X to time t could be described by the equation K= mtn-1where m and n are the coefficients). When n>1, the coating penetrability was gradually increased, and the urea release from PCU was accelerated; when n=1, the coating penetrability was steady, and the urea release from PCU obeyed the first-order kinetics; and when n<1.the coating penetrability was gradually decreased, and the urea release from PCU was delayed, resulting in a significant 'tailing effect'. 展开更多
关键词 Polymer coated urea Urea release kinetics Coating penetrability FITTING
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Problem of Nuclear Decay by Proton Emission in Fully Quantum Consideration: Calculations of Penetrability and Role of Boundary Conditions
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作者 Sergei P Maydanyuk Sergei V Belchikov 《Journal of Modern Physics》 2011年第6期572-585,共14页
We develop a new fully quantum method for determination of widths for nuclear decay by proton emission where multiple internal reflections of wave packet describing tunneling process inside proton-nucleus radial barri... We develop a new fully quantum method for determination of widths for nuclear decay by proton emission where multiple internal reflections of wave packet describing tunneling process inside proton-nucleus radial barrier are taken into account. Exact solutions for amplitudes of wave function, penetrability T and reflection R (estimated for the first time for decay problem) are found for n -step barrier (at arbitrary n) which approximates the realistic barrier. In contrast to semiclassical approach and two-potential approach, we establish by this method essential dependence of the penetrability on the starting point Rform in the internal well where proton starts to move outside (for example, for Ta the penetrability is changed up to 200 times;accuracy is T+R-1|-15 ). We impose a new condition: in the beginning of the proton decay the proton starts to move outside from minimum of the well. Such a condition provides minimal calculated half-life and gives stable basis for predictions. However, the half-lives calculated by such an approach turn out to be a little closer to experimental data in comparison with the semiclassical half-lives. Estimated influence of the external barrier region is up to 1.5 times for changed penetrability. 展开更多
关键词 TUNNELING Multiple Internal REFLECTIONS Wave Packet DECAY by PROTON Emission penetrability and Reflection HALF-LIFE
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Analyzing and Projecting Soil Moisture and Cone Penetrability Variations in Forest Soils
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作者 Marie-France Jones Paul Arp 《Open Journal of Forestry》 2019年第2期109-142,共34页
This article details how forest soil moisture content (MC) and subsequent resistances to cone penetration (referred below as Cone Index, CI) vary by daily weather, season, topography, site and soil properties across e... This article details how forest soil moisture content (MC) and subsequent resistances to cone penetration (referred below as Cone Index, CI) vary by daily weather, season, topography, site and soil properties across eleven harvest blocks in northwestern New Brunswick. The MC- and CI-affecting soil variables refer to density, texture, organic matter content, coarse fragment content, and topographic position (i.e., elevation, and the seasonally affected cartographic depth-to-water (DTW) pattern). The harvest blocks were transect-sampled inside and outside their wood-forwarding tracks at varying times throughout the year. In detail, 61% of the pore-filled moisture content (MCPS) determinations inside and outside the tracks could be related to topographic position, coarse fragments, bulk density, and forest cover type specifications. In addition, 40% of the CI variations could be related to soil depth, MCPS, and block-specific cover type. Actual versus model-projected uncertainties amounted to ΔMCPS ≤ ± 15% and ΔCI ≤ ± 0.5 MPa, 8 times out of 10. Block-centered MC and CI projections were obtained through: 1) daily hydrological modelling using daily precipitation and air temperature weather-station records nearest each block, and 2) digitally mapped variations in soil properties, elevation, DTW and forest cover type, done at 10 m resolution. 展开更多
关键词 Forest SOILS Soil Moisture CONE Penetration Digital ELEVATION Modelling Cartographic Depth-to-Water MULTILINEAR Regression CONFUSION Matrix
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Liposomes Carrying Diclofenac Diethylammonium: A Penetrability and Permeation Study
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作者 Adriana Camino Anyoli Taly +3 位作者 Cirana Rodriguez Alfredo Inatti Evelyn Pena Xenon Serrano 《Journal of Biosciences and Medicines》 2024年第12期206-218,共13页
This study investigated whether liposomes could enhance the permeation and penetration of diclofenac diethylammonium. For this, a 1.16% diclofenac diethylammonium liposome gel formulation was developed (Grupo Leti, S.... This study investigated whether liposomes could enhance the permeation and penetration of diclofenac diethylammonium. For this, a 1.16% diclofenac diethylammonium liposome gel formulation was developed (Grupo Leti, S.A.V.). In vitro and ex vivo tests were conducted to analyze the diffusion and penetration profiles of the formulation. The profiles obtained were compared with a commercially available product, DiAnalper gel (Pharmetique Labs). The in vitro test was assessed in a Franz diffusion cell system using a dialysis membrane. The cumulative amount of drug permeated after 24 h demonstrated a significantly (p 2, whereas the commercial formulation yielded values of 371.00 ± 3.54 μg/cm2. These findings were further supported by consistent results in the percentage of drug release, flux, and permeability coefficient, all indicating a notable improvement in diffusion associated with the liposomal gel formulation. The tape stripping assay performed on pig ear skin demonstrates a statistically significant difference (p < 0.05) between the penetration transport of the diclofenac from liposome gel formulation (1413.95 ± 250.51 μg) and the conventional product (202.36 ± 18.07 μg) the liposomal formulation was able to cross de stratum corneum and deliver a high amount of drug to the skin. These findings demonstrated that incorporating diclofenac into a liposomal system significantly improved the drug delivery, which could confer an advantage for clinical uses. 展开更多
关键词 Liposomes Diclofenac Diethylammonium Transdermal Drug Delivery Skin Permeation Skin Penetration
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Effect of Spudcan Penetration Angles on Adjacent Bucket Foundation in Sand
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作者 Conghuan Le Zhenqi He +2 位作者 Hao Hu Puyang Zhang Hongyan Ding 《哈尔滨工程大学学报(英文版)》 2026年第1期95-109,共15页
Installing internal bulkheads in a composite bucket foundation alters the rotational symmetry characteristic of a single-compartment bucket foundation,consequently influencing the stress distribution within the bucket... Installing internal bulkheads in a composite bucket foundation alters the rotational symmetry characteristic of a single-compartment bucket foundation,consequently influencing the stress distribution within the bucket and surrounding soil.During the seabed penetration of a spudcan from a jack-up wind turbine installation vessel,an angle may form between the spudcan’s axis and the axis of symmetry of the adjacent composite bucket foundation in the horizontal plane.Such a misalignment may affect load distribution and the non-uniform interaction between the foundation,soil,and spudcan,ultimately influencing the foundation’s stability.This study employs physical model tests to ascertain the trends in end resistance during spudcan penetration in sand,the extent of soil disturbance,and the backflow condition.The finite element coupled Eulerian-Lagrangian method is validated and utilized to determine the range of penetration angles that induce alterations in the maximum vertical displacement and tilt rate of the composite bucket foundation in sand.The differential contact stress distribution at the base of the bucket is analyzed,with qualitative criteria for sand backflow provided.Findings demonstrate that the maximum vertical displacement and tilt rate of the composite bucket foundation display a“wave-like”variation with the increasing spudcan penetration angle,peaking when the angle between the spudcan and bulkhead is the smallest.Stress distribution is predominantly concentrated at the base and apex of the bucket,becoming increasingly uneven as the penetration angle deviates from the foundation’s symmetry axis.The maximum stress gradually shifts to the junction of the bulkhead and bucket bottom on the side with the shortest net distance from the spudcan.Considering the in-place stability and stress state of the composite bucket foundation is therefore imperative,and particular attention should be paid to the foundation’s state when the angle between the spudcan and bulkhead is small. 展开更多
关键词 Spudcan penetration Soil disturbance Penetration angle Composite bucket foundation Coupled Eulerian-Lagrangian
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Mechanisms of Concrete Durability against Seawater(Case Study:Concrete as Dock)
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作者 Niken Chatarina Suyadi Suyadi +2 位作者 Noorhidana Vera Agustriana Chairani Zilia Mariyanto Mariyanto 《Structural Durability & Health Monitoring》 2026年第2期213-234,共22页
In strong aggressive areas,Indonesian standards specify a maximum penetration of 30 mm.Concrete utilizes sulfate-resistant Portland Pozzolan Cement(PPC)for a target strength of 30 MPa,with and without silica fume and ... In strong aggressive areas,Indonesian standards specify a maximum penetration of 30 mm.Concrete utilizes sulfate-resistant Portland Pozzolan Cement(PPC)for a target strength of 30 MPa,with and without silica fume and plastic fiber(SR-SFF-sea and SR-N-SFF).Some samples of SR-N-SFF are immersed in the sea(SR-N-SFF-sea),while others are protected(SR-N-SFF-protected).Additionally,concrete using non-sulfate-resistant cement(NSR-sea)with a strength of 20.75 MPa was also evaluated.All samples were subjected to penetration depth testing according to the DIN EN 12390-8 standard,demonstrating that they met the penetration requirements for intense aggression.The study employed cylindrical samples measuring 15 cm in diameter and 30 cm in height to assess compressive strength and natural penetration fromthe split tensile test.Samples were placed into the sea at the fishing boat dock in Lampung,Indonesia,at 9 days of age following 7 days of immersion curing.The results indicated that sulfate-resistant Portland Composite Cement(PCC)is unsuitable for protected areas,as its strength is inferior to that of concrete submerged in seawater.Concrete featuring sulfate-resistant PCC,silica fume,and plastic fiber(SR-SFF-sea)exhibited lower strength compared to SR-N-SFF-protected samples.Conversely,SR-N-SFF-sea achieved the highest strength of 46 MPa at 56 days,with a notable increase in strength occurring from 21 to 56 days,while no increase in penetration depth was observed during this period.The standard penetration depth of SR-N-SFF-sea is 17.8mm,which can serve as a guideline for creating durable concrete in marine environments. 展开更多
关键词 CONCRETE PENETRATION PET fiber PPC sea silica fume sulfate resistant cement
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A Review on Penetration Testing for Privacy of Deep Learning Models
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作者 Salma Akther Wencheng Yang +5 位作者 Song Wang Shicheng Wei Ji Zhang Xu Yang Yanrong Lu Yan Li 《Computers, Materials & Continua》 2026年第5期43-76,共34页
As deep learning(DL)models are increasingly deployed in sensitive domains(e.g.,healthcare),concerns over privacy and security have intensified.Conventional penetration testing frameworks,such asOWASP and NIST,are effe... As deep learning(DL)models are increasingly deployed in sensitive domains(e.g.,healthcare),concerns over privacy and security have intensified.Conventional penetration testing frameworks,such asOWASP and NIST,are effective for traditional networks and applications but lack the capabilities to address DL-specific threats,such asmodel inversion,membership inference,and adversarial attacks.This review provides a comprehensive analysis of penetration testing for the privacy of DL models,examining the shortfalls of existing frameworks,tools,and testing methodologies.Through systematic evaluation of existing literature and empirical analysis,we identify three major contributions:(i)a critical assessment of traditional penetration testing frameworks’inadequacies when applied to DL-specific privacy vulnerabilities,(ii)a comprehensive evaluation of state-of-the-art privacy-preserving methods and their integration with penetration testing workflows,and(iii)the development of a structured framework that combines reconnaissance,threat modeling,exploitation,and post-exploitation phases specifically tailored for DL privacy assessment.Moreover,this review evaluates popular solutions such as IBMAdversarial Robustness Toolbox and TensorFlowPrivacy,alongside privacy-preserving techniques(e.g.,Differential Privacy,Homomorphic Encryption,and Federated Learning),which we systematically analyze through comparative studies of their effectiveness,computational overhead,and practical deployment constraints.While these techniques offer promising safeguards,their adoption is hindered by accuracy loss,performance overheads,and the rapid evolution of attack strategies.Our findings reveal that no single existing solution provides comprehensive protection,which leads us to propose a hybrid approach that strategically combines multiple privacy-preserving mechanisms.The findings of this survey underscore an urgent need for automated,regulationcompliant penetration testing frameworks specifically tailored to DL systems.We argue for hybrid privacy solutions that combinemultiple protectivemechanisms to ensure bothmodel accuracy and privacy.Building on our analysis,we present actionable recommendations for developing adaptive penetration testing strategies that incorporate automated vulnerability assessment,continuous monitoring,and regulatory compliance verification. 展开更多
关键词 Penetration testing deep learning homomorphic encryption differential privacy federated learning
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Characteristics of gas−liquid flow in double-side-blown systems computed by CFD
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作者 Wei WANG Hong-liang ZHAO +1 位作者 Feng-qin LIU Hong Yong SOHN 《Transactions of Nonferrous Metals Society of China》 2026年第2期659-676,共18页
A CFD-based numerical model was employed to quantitatively analyze the flow characteristics of double-side-blown gas−liquid flow.Key parameters were extracted,and Spearman correlation analysis was used to quantify the... A CFD-based numerical model was employed to quantitatively analyze the flow characteristics of double-side-blown gas−liquid flow.Key parameters were extracted,and Spearman correlation analysis was used to quantify the relationships among bubble behavior,circulating flow,and liquid oscillations.The results show that periodic bubble behavior under steady injection drives the circulating flow of the liquid on both sides.The asynchronism of bubble behavior on both sides results in the alternation of circulating intensity,which significantly enhances gas−liquid mixing efficiency at certain liquid levels of 200 and 220 mm.Flow patterns of the double-side-blown process are classified into weak circulation,strong−weak alternating circulation,and strong circulation modes based on the influence of circulating flows on the penetration depth.The penetration depth in the strong−weak alternating circulation mode is generally greater than that in the single-side-blown process.The imbalance of circulating intensities on both sides primarily leads to the stable fluctuation in the injecting direction,which reveals the appearance of periodic oscillations in the molten bath.The effect of control parameters such as liquid level and gas flow rate on the liquid oscillations were discussed. 展开更多
关键词 numerical simulation side-blown furnace flow characteristics bubble behavior penetration depth Spearman correlation analysis
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Systematic study of laser-assisted cluster radioactivity for deformed nuclei
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作者 Leng-Jun Liao Lin-Jing Qi +2 位作者 Xi-Jun Wu Xiao-Hua Li Ming Li 《Nuclear Science and Techniques》 2026年第4期232-242,共11页
In this study,the effects of laser fields that can be achieved in the near future on cluster penetration probability and half-life are quantitatively investigated.The calculation results show that extreme laser fields... In this study,the effects of laser fields that can be achieved in the near future on cluster penetration probability and half-life are quantitatively investigated.The calculation results show that extreme laser fields can slightly change the cluster-decay half-life by affecting the penetration probability within a narrow range.Subsequently,we discuss the correlation between the change rate of the penetration probability and the tunneling path.The results indicate that for different parent nuclei emitting the same cluster,nuclei with longer tunneling paths are more easily affected by the laser fields.The shell effect on this correlation is also observed.In addition,the impact of laser fields on the penetration probability in any direction is investigated. 展开更多
关键词 Cluster radioactivity HALF-LIFE Extreme laser field Penetration probability
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Resistance of Calcium Sulphoaluminate Cement-based Coral Sand Mortar to Chloride Ingress
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作者 YU Zhuqing LONG Yu WANG Haonan 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期107-115,共9页
The utilization of discarded coral debris in cementitious material is a prominent research area for island construction projects.The aim of this study is to explore the use of environment-friendly cement and waste cor... The utilization of discarded coral debris in cementitious material is a prominent research area for island construction projects.The aim of this study is to explore the use of environment-friendly cement and waste coral sand in the preparation of coral mortar,while investigating its performance when exposed to a chloride environment.Three types of low-carbon cements were employed,such as rapid hardening sulphoaluminate(RCSA)cement,high belite sulphoaluminate(HBCSA)cement,and slag sulphoaluminate cement(SSC).The coulomb electric flux,mechanical properties,free chloride content,and mass change of the cement mortar under exposed to 3.5 wt%NaCl solution were examined at various time intervals.X-ray diffraction analysis was conducted to identify the mineral phases present in the mortar samples.The results demonstrate that the flexural and compressive strength of the mortar consistently increase throughout the 360 days chloride exposure period.Incorporating coral sand into SSC-based mortars enhances their compressive strength from day 28 up until day 360.However,it adversely affects the strength of HBCSA-based mortars.The behavior of mortars exposed to a chloride-rich environment is closely associated with the amount of C-S-H gel present within them.SSC generates a significant quantity of C-S-H gel which possesses a large specific surface area capable of absorbing more chloride ions thereby reducing their concentration within the mortar matrix as well as increasing its mass and improving resistance against chloride ion penetration. 展开更多
关键词 calcium sulphoaluminate cement coral sand chloride penetration coral mortar
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PenCards:a global and community-contributed public archive of variant penetrance
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作者 Zhaopo Zhu Ling Shang +7 位作者 Chuhan Shao Zheng Wang Xinxin Mao Yuanfeng Huang Pei Yu Bin Li Jinchen Li Guihu Zhao 《Journal of Genetics and Genomics》 2026年第2期332-342,共11页
Penetrance is a crucial indicator for accurately assessing disease risk and plays a vital role in disease research,gene therapy,and genetic counseling.However,with penetrance data dispersed across various sources,effi... Penetrance is a crucial indicator for accurately assessing disease risk and plays a vital role in disease research,gene therapy,and genetic counseling.However,with penetrance data dispersed across various sources,efficiently accessing and consolidating this information becomes a challenge.A comprehensive platform that integrates penetrance is urgently needed.Here,we present PenCards,a global,community-contributed public archive of variant penetrance,by first collecting penetrance data from all published literature and then using large international cohorts to specifically calculate the penetrance of autism-related variants.PenCards contains a total of 244,531 variants,including 239,244 single nucleotide variants,4994 insertions and deletions,and 293 copy number variants,covering approximately 300 phenotypes.We also provide a submission portal for the dynamic updating of penetrance.Additionally,to help users efficiently access genetic information,we comprehensively integrate over 150 variant-and gene-level resources.In summary,PenCards is a powerful platform designed to advance genetic research and diagnostics.PenCards is publicly available at https://genemed.tech/pencards/. 展开更多
关键词 PENETRANCE Disease risk Genetic research and diagnostics Secondary findings Human genomics
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The effects of compressibility and target strength on shaped charge jet penetration
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作者 Qiangqiang Xiao Zhengxiang Huang +2 位作者 Xudong Zu Xin Jia Bin Ma 《Defence Technology(防务技术)》 2026年第2期244-253,共10页
The penetration of shaped charge jets into targets at high velocities is significantly influenced by the compressibility effect,while at low velocities,the strength effect becomes predominant.In the latter regime,mate... The penetration of shaped charge jets into targets at high velocities is significantly influenced by the compressibility effect,while at low velocities,the strength effect becomes predominant.In the latter regime,material strength dictates the resistance to plastic deformation and flow,a contrast to the shockwave-dominated interactions where compressibility is key.This paper presents a self-consistent compressible penetration theory that considers both the axial penetration and radial crater growth of shaped charge jets into targets.An integrated approach where the axial and radial dynamics are coupled has been proposed,influencing each other through shared physical principles rather than being treated as separate,empirically linked phenomena.The presented theory is rooted in the compressible Bernoulli equation and the linear Rankine-Hugoniot relation.These foundational equations are employed to accurately model the high-pressure shock state and subsequent material flow at the jet-target interface,providing a robust physical basis for the penetration model.Notably,it considers the target material's compressibility,which elevates the pressure at the jet-target interface beyond that observed with incompressible materials.This pressure increase is directly proportional to the target's degree of compressibility.As such,this model of compressible penetration reorients the analytical approach:rather than merely estimating penetration resistance,it determines this value from the target material's specific compressibility and yield strength.This shift from empirical correlations to a physics-based derivation of penetration resistance enhances the model's predictive power,particularly for novel target materials or engagement conditions outside established experimental datasets.This investigation establishes a quantitative link between the material's yield strength and its penetration resistance.The accuracy of this penetration resistance value is paramount,as it significantly influences the predicted crater diameter;indeed,the crater diameter's sensitivity to this resistance underscores the necessity for its precise determination.Ultimately,by integrating the yield strength of the target material,this framework enables the prediction of both the penetration depth and the resultant crater diameter from a shaped charge jet.The theory's validation involved two experimental sets:the first focused on shaped charge jet penetration into 45#steel at varied stand-offs,while the second utilized targets of high-to ultrahigh-strength steel-fiber reactive powder concrete(RPC)with differing strength characteristics.These experimental campaigns were specifically chosen to test the theory against both ductile metallic alloys,where plastic flow is significant,and advanced quasi-brittle cementitious composites,presenting a broad spectrum of material responses and penetration challenges.Resulting hole profiles derived from theoretical calculations demonstrated a strong correspondence with empirical measurements for both material types. 展开更多
关键词 Shaped charge jet Penetration efficiency Compressibility influence Strength impact
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Dielectric constant influences and mechanical correlations in asphalt mixtures:Implications for non-destructive testing
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作者 Hao Hu Guoping Qian +5 位作者 Huanan Yu Yixiong Zhong Yutang Gao Wan Dai Jinguo Ge Chao Zhang 《Journal of Road Engineering》 2026年第1期122-133,共12页
Ground penetrating radar(GPR)offers a rapid and non-destructive approach to evaluating asphalt mixtures by capturing variations in their dielectric constant.As a critical electromagnetic parameter,the dielectric const... Ground penetrating radar(GPR)offers a rapid and non-destructive approach to evaluating asphalt mixtures by capturing variations in their dielectric constant.As a critical electromagnetic parameter,the dielectric constant demonstrates significant potential for assessing the material composition and mechanical properties of asphalt mixtures.However,the relationship between the dielectric constant and mechanical properties remains unclear.To investigate the factors affecting the dielectric constant and its correlation with the mechanical properties of asphalt mixtures,a systematic analysis of the influencing parameters was conducted.Fitting equations were established to quantify the relationships between the dielectric constant and mechanical properties.Firstly,the effects of compaction state,testing frequency,and testing temperature on the dielectric constant were evaluated.Subsequently,forward simulations of GPR were executed on asphalt pavements with diverse air voids and detection frequencies.Finally,a fitting analysis was performed to determine the correlation between the dielectric constant and the dynamic modulus,compressive strength,and splitting tensile strength.The results indicated that the dielectric constant increased with the compaction state,decreased with increasing testing frequency until stabilized,and was insignificantly affected by changes in testing temperature.The change of air void in asphalt pavement has significantly affected the amplitude and timing of electromagnetic wave reflection.A linear positive correlation was identified between the dielectric constant and dynamic modulus as well as compressive strength,while a quadratic positive correlation existed with splitting tensile strength.This study provided theoretical and practical foundations for enhancing the reliability and accuracy of non-destructive testing in asphalt pavement. 展开更多
关键词 Ground penetrating radar Compaction state Frequency sensitivity Forward modeling Pavement evaluation
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Pile installation effects in natural soft clays:A semi-analytical solution using strain path method
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作者 Liang Li Pan Zhou +3 位作者 Jingpei Li Seyedmohsen Miraei Peng Feng Mingdong Wei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期728-744,共17页
This paper develops a semi-analytical solution for pile penetration in natural soft clays using the strain path method(SPM).The stress-strain behavior of soils is characterized by the S-CLAY1S model,which can capture ... This paper develops a semi-analytical solution for pile penetration in natural soft clays using the strain path method(SPM).The stress-strain behavior of soils is characterized by the S-CLAY1S model,which can capture the anisotropic evolution and destructuring nature of soft clays.By integrating the S-CLAY1S model into the theoretical framework of the SPM,a set of ordinary differential equations is formulated with respect to the vertical coordinate of soil particles.The distribution of excess pore water pressure(EPWP)following pile installation is approximated through one-dimensional(1D)radial integration around the pile shaft.The distribution of stresses and EPWP,along with the evolution of fabric anisotropy within the soil surrounding the pile,is presented to illustrate the response of pile penetration in natural soft clays.The proposed solution is validated against existing theoretical solutions using the SPM and cavity expansion method(CEM),along with experimental data.The findings demonstrate that the SPM reveals lower radial effective stresses and EPWP at the pile shaft than that of CEM.Pile penetration alters the soil's anisotropic properties,inducing rotational hardening and affecting post-installation stress distribution.Soil destructuration eliminates bonding among particles near the pile,resulting in a complete disruption of soil structure at the pile surface,which is particularly pronounced for higher initial soil structure ratios.Minimal variation was observed in the three principal stresses and shear stress on the cone side surface as the angle increased from 18°to 60°,except for a slight reduction in EPWP. 展开更多
关键词 Pile penetration Strain path method Natural soft clays Anisotropy evolution Destructuration
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Linxing-Shenfu Gangue Interaction Coal Seam Hydraulic Fracture Cross-Layer Expansion Mechanism
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作者 Li Wang Xuesong Xing +4 位作者 Yanan Hou Heng Wen Ying Zhu Jingyu Zi Qingwei Zeng 《Energy Engineering》 2026年第2期279-293,共15页
The deep coal reservoir in Linxing-Shenfu block of Ordos Basin is an important part of China’s coalbed methane resources.In the process of reservoir reconstruction,the artificial fracture morphology of coal seam with... The deep coal reservoir in Linxing-Shenfu block of Ordos Basin is an important part of China’s coalbed methane resources.In the process of reservoir reconstruction,the artificial fracture morphology of coal seam with gangue interaction is significantly different,which affects the efficient development of coalbed methane resources in this area.In this paper,the surface outcrop of Linxing-Shenfu block is selected,and three kinds of interaction modes between gangue and coal seam are set up,including single-component coal rock sample,coal rock sample with different thicknesses of gangue layer and coal rock sample with different numbers of gangue.Through true triaxial physical simulation and three-dimensional discrete element numerical simulation,the lawof artificial fracture initiation and propagation in multi-gangue interaction coal seam is analyzed in depth,and the hydraulic fracture initiation and propagation mode under different interaction modes of gangue layer in Linxing-Shenfu deep coal reservoir was clarified.The research shows that the initiation of artificial fractures in a single coal seam is affected by geologicalengineering factors.The maximum principal stress dominates the direction of fracture propagation,and the stress difference controls the fracture morphology.When the stress difference is 2 MPa,the fracture morphology is complex,which is easy to connect to the weak surface of coal and rock cleat,and the fracturemorphology of the stress difference is mainly a single main fracture.After the thickness of the gangue layer is increased from 2 to 5 cm,it is difficult for the artificial fracture to penetrate the layer vertically after the fracture initiation,and the effective transformation area of the reservoir is limited.The more the number of gangue layers,the greater the hydraulic energy consumption in the process of fracture propagation,and the more difficult the fracture propagation. 展开更多
关键词 Deep coal reservoir true triaxial layer penetration fracturing reservoir reconstruction
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Experimental study on damage characteristics of t-shaped stiffened plates subjected to different types of shaped charges:Linear-shaped charge,embowed linear-shaped charge,and embowed linear explosively formed projectile
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作者 Shenhe Zhang Zhifan Zhang +4 位作者 Shuxin Yang Longkan Wang Yutong Sui Guiyong Zhang Zhi Zong 《Defence Technology(防务技术)》 2026年第2期231-243,共13页
In order to investigate the penetration performance of Linear-Shaped Charge(LSC),Embowed LinearShaped Charge(ELSC),and Embowed Linear Explosively Formed Projectile(ELEFP)on T-shaped stiffened plates,a series of near-f... In order to investigate the penetration performance of Linear-Shaped Charge(LSC),Embowed LinearShaped Charge(ELSC),and Embowed Linear Explosively Formed Projectile(ELEFP)on T-shaped stiffened plates,a series of near-field air-burst experiments are conducted.The damage modes and characteristics of the target plates are compared and analyzed.Each flat plate section is completely punctured,resulting in a penetration hole.The damage modes induced by the three charge types on the stiffened plate structure are consistent,characterized by shear failure in the central region of the flat plate due to penetration by the penetrator,localized plastic deformation of the flat plate,and local penetration failure resulting from partial perforation of the central stiffener.The penetration lengths caused by ELSC and ELEFP are 45.1%and 46.1% larger than that of LSC,while the half-width of the penetration hole generated by ELEFP is 54.2% and 24.7% smaller than that of ELSC and LSC,respectively.The penetration height caused by ELEFP are 17.5%and 62.1% larger than that of ELSC and LSC,respectively.The stiffener effectively segments the damage area,enhancing the local structural strength and limiting the extent of plastic deformation in the flat plate section.The comparative results show that the ELSC proves to be more effective for efficient large-scale damage,and ELEFP is more suitable for achieving efficient localized damage. 展开更多
关键词 Linear-shaped charge Embowed linear-shaped charge Embowed linear explosively formed PROJECTILE Near-filed explosion Penetration performance Stiffened plate
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China's Automotive Surge in Europe
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作者 Alice Yang 《China's Foreign Trade》 2026年第1期48-50,共3页
For decades,Europe's automotive landscape was dominated by homegrown marques——Volkswagen,Renault,BMW——and long-established Japanese and Korean challengers.Change was slow and predictable.In 2025,that assumptio... For decades,Europe's automotive landscape was dominated by homegrown marques——Volkswagen,Renault,BMW——and long-established Japanese and Korean challengers.Change was slow and predictable.In 2025,that assumption finally broke.Chinese automotive brands,once marginal on European roads,reached a historic high. 展开更多
关键词 Market penetration Industry change homegrown marques volkswagenrenaultbmw Chinese automotive brands European automotive landscape
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Algae penetration and taste and odor compounds production in drinking water treatment plants:seasonal variations and risk assessment
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作者 Ya Cheng Caiyun Ma +5 位作者 Gang Wen Chaoyang Zheng Wenle Tian Kailin Sha Xinru Han Tinglin Huang 《Journal of Environmental Sciences》 2026年第2期319-329,共11页
In the conventional water treatment process,algae have a propensity to breach the filter barriers and potentially seep into the water distribution system,leading to an elevation in taste and odor compounds(T&O com... In the conventional water treatment process,algae have a propensity to breach the filter barriers and potentially seep into the water distribution system,leading to an elevation in taste and odor compounds(T&O compounds).This investigation delved into the seasonal fluctuations of algae penetration and the production of T&O compounds within the treatment units of Reservoir Water Plant 1(W1)and River Water Plant 2(W2).The findings indicated that despite the application of the‘pre-oxidation,coagulation and sedimentation(PCS),sand filtration,and disinfection’process,certain robust-walled filamentous Cyanobacteria,Bacillariophyta species,and small Chlorophyta genera managed to bypass the filters.The leakage of algal cells during autumn at W1 was particularly striking,with a peak of 1,170,000 cells/L.The concurrent assessment of the potential for T&O compound formation revealed an alarming high potential for 2-methylisoborneol(2-MIB)in the water leaving the plants,with concentrations soaring to 197.20 ng/L at W1 in autumn and 54.78 ng/L at W2 in summer.This underscores the significant capacity of residual algal cells to generate T&O compounds.Tracking the retention and penetration dynamics of algal cells across each drinking water treatment stage is crucial for surface water treatment facilities to develop effective operational and management strategies,thereby enhancing the safety and quality of drinking water for the end consumer. 展开更多
关键词 CYANOBACTERIA Surface water treatment plant Algae penetration Taste and odor compounds 2-METHYLISOBORNEOL
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