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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 Plant Roots on Penetrability and Anti-Scouri-bility of Red Soil Derived from Granite 被引量:18
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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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Resistance of Cement-based Grouting Materials with Nano- SiO_(2) Emulsion to Chloride Ion Penetration
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作者 LI Shuiping CHENG Jian +2 位作者 WEI Chao YUAN Bin YU Chengxiao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期114-119,共6页
The chloride penetration resistance of cement-based grout materials was improved by nano-silica emulsion.Specimens of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride so... The chloride penetration resistance of cement-based grout materials was improved by nano-silica emulsion.Specimens of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test ages.Hardened properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction(XRD)and scanning electron microscopy(SEM)of mixes were performed to analysis the phase evolution and microstructure.The results demonstrated that the introduction of nano-SiO_(2) emulsion significantly decreased the compressive strength loss and calcium hydroxide(CH)crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion penetration.This improvement derives from the filling and pozzolanic effects of nano-SiO_(2) particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix. 展开更多
关键词 grouting materials nano-SiO_(2)emulsion chloride ion penetration weight loss strength loss
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Kali Pi—A Miniature Ultra-Portable Penetration Testing Device
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作者 Ahmed Bin Ali 《Journal of Information Security》 2025年第1期101-113,共13页
Penetration testing plays a critical role in ensuring security in an increasingly interconnected world. Despite advancements in technology leading to smaller, more portable devices, penetration testing remains reliant... Penetration testing plays a critical role in ensuring security in an increasingly interconnected world. Despite advancements in technology leading to smaller, more portable devices, penetration testing remains reliant on traditional laptops and computers, which, while portable, lack true ultra-portability. This paper explores the potential impact of developing a dedicated, ultra-portable, low-cost device for on-the-go penetration testing. Such a device could replicate the core functionalities of advanced penetration testing tools, including those found in Kali Linux, within a compact form factor that fits easily into a pocket. By offering the convenience and portability akin to a smartphone, this innovative device could redefine the way penetration testers operate, enabling them to carry essential tools wherever they go and ensuring they are always prepared to conduct security assessments efficiently. This approach aims to revolutionize penetration testing by merging high functionality with unparalleled portability. 展开更多
关键词 Penetration Testing Portable Device CYBERSECURITY Raspberry Pi
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Response properties of geometries of coal penetrating fracture on seepage behavior
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作者 Penghua Han Kai Wang +2 位作者 Jiewen Pang Xiaofeng Ji Cun Zhang 《International Journal of Mining Science and Technology》 2025年第2期191-211,共21页
The fracture surfaces of coal-rock masses formed under mining-induced stress generally exhibit complex geometries, and the fracture geometry is one of the primary factors affecting the seepage characteristics of coal-... The fracture surfaces of coal-rock masses formed under mining-induced stress generally exhibit complex geometries, and the fracture geometry is one of the primary factors affecting the seepage characteristics of coal-rock penetrating fracture. This paper investigates the seepage characteristics of 5 groups of coal penetrating fracture(CPF) with different joint roughness coefficients(JRCs). Based on 3D morphology scanner tests and hydraulic coupling tests, a characterization method of effective geometric parameters in fracture surfaces under various confining pressures was improved, and a relationship between effective geometric parameters and the confining pressure is established. The results indicate that the nonlinear flow behavior in a CPF primarily includes three types: non-Newtonian fluid seepage under high confining pressure and low JRC, non-Darcy seepage under low confining pressure and high JRC, and the whole process of seepage characteristics between these two conditions. Among them, nonNewtonian fluid seepage is caused by significant fracture expansion, while non-Darcy seepage can be attributed to turbulence effects. During the seepage process, the geometric parameters with different JRC fracture samples all exhibit exponential changes with the increase of confining pressure. In addition,under high confining pressure, the effective contact ratio, effective fracture aperture, and void deviation ratio with high JRC fracture samples under high confining pressure increase by 93.5%, 67.4%, and 24.9%,respectively, compared with those of low JRC fracture samples. According to the variation of geometric parameters in a CPF with external stress, a seepage model considering geometric parameters in a CPF is proposed. By introducing the root mean square error(RMSE) and coefficient of determination(R2) to evaluate the error and goodness of fit between model curves and experimental data, it is found that the theoretical curves of model in this paper have the best matching with the experimental data. The average values of RMSE and R2for model in this paper are 0.002 and 0.70, respectively, which are better than models in the existing literature. 展开更多
关键词 Coal penetrating fracture ROUGHNESS GEOMETRIES Seepage characteristics
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Perspectives on additive manufacturing for warhead applications
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作者 Hao Xue Qiang Zhou +1 位作者 Chuan Xiao Guangyan Huang 《Defence Technology(防务技术)》 2025年第1期225-251,共27页
According to different damage modes,warheads are roughly divided into three types:fragmentation warheads,shaped charge warheads,and penetrating warheads.Due to limitations in material and structural manufacturing,trad... According to different damage modes,warheads are roughly divided into three types:fragmentation warheads,shaped charge warheads,and penetrating warheads.Due to limitations in material and structural manufacturing,traditional manufacturing methods make it difficult to fully utilize the damage ability of the warhead.Additive manufacturing(AM)technology can fabricate complex structures,with classified materials composition and customized components,while achieving low cost,high accuracy,and rapid production of the parts.The maturity of AM technology has brought about a new round of revolution in the field of warheads.In this paper,we first review the principles,classifications,and characteristics of different AM technologies.The development trends of AM technologies are pointed out,including multi-material AM technology,hybrid AM technology,and smart AM technology.From our survey,PBF,DED,and EBM technologies are mainly used to manufacture warhead damage elements.FDM and DIW technologies are mainly used to manufacture warhead charges.Then,the research on the application of AM technology in three types of warhead and warhead charges was reviewed and the existing problems and progress of AM technologies in each warhead were analyzed.Finally,we summarized the typical applications and look forward to the application prospects of AM technology in the field of warheads. 展开更多
关键词 Additive manufacturing Fragmentation warhead Shaped charge warhead Penetrating warhead Warhead charge
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Laser-assistedαdecay of the deformed odd-A nuclei
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作者 Jun-Hao Cheng Qiong Xiao +3 位作者 Jun-Gang Deng Yang-Yang Xu You-Tian Zou Tong-Pu Yu 《Nuclear Science and Techniques》 2025年第4期181-198,共18页
In this study,we explore the impact of state-of-the-art laser fields on theαdecay half-life of deformed ground-state odd-A nuclei within the proton number range of 52–107.The calculations show that the presence of a... In this study,we explore the impact of state-of-the-art laser fields on theαdecay half-life of deformed ground-state odd-A nuclei within the proton number range of 52–107.The calculations show that the presence of a laser field modulates theαdecay half-life by altering theαdecay penetration probability within a limited range.Moreover,the variance in the penetration probability rate of change between even–odd and odd–even nuclei is investigated.Furthermore,we investigate the rate of change of the penetration probability for the same parent nucleus with different neutron numbers,based on the characteristics of the odd-A nucleus.We found that the influence of the laser field on the penetration probability is determined by both the shell effect and odd–even staggering.This research contributes to the understanding of nuanced interactions between laser fields and nuclear decay processes.Therefore,valuable insights for future experiments in laser–nuclear physics are attainable using this study. 展开更多
关键词 αdecay Odd-A nuclei HALF-LIFE Extreme laser field Penetration probability
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New digital drilling process monitoring: Instrumentation, validation and calibration
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作者 Yanpeng Sun Zuyu Chen +3 位作者 Fangcai Xu Yufei Zhao Ruilang Cao Dong Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期31-54,共24页
This study aims to enhance the digital drilling process monitoring(DPM)or monitoring while drilling(MWD)technique,which is a widely recognized method in geological exploration for evaluating rock mass quality.First,ro... This study aims to enhance the digital drilling process monitoring(DPM)or monitoring while drilling(MWD)technique,which is a widely recognized method in geological exploration for evaluating rock mass quality.First,robust displacement and torque measurement facilities for rotary-core drilling are discussed.The conventional cable encoder for displacement measurement is replaced with a magnetostrictive displacement sensor,which is more reliable in harsh field drilling environments.This enables the measurement of the bit position with an accuracy of<1 mm.Most importantly,this new instrument is proven to be successful in improving the detection of structural discontinuities with thicknesses>1 mm.In addition,by measuring the electric current of the driving motor,the torque applied to the bit is conveniently and accurately converted.These innovations ensure high-quality data collection for DPM practices.Second,two indices derived from DPM are proposed to quantitatively describe rock mass quality.The specific energy index(SEI)and specific penetration index(SPI)are based on the principles of energy conservation and Mohr-Coulomb failure criterion,respectively.Extensive field tests conducted in a dam grouting area confirm a linear relationship between the thrust force and penetration per rotation,and between the torque and penetration per rotation.The correlation ratios of the related regressions are typically>0.9.These two indices allow for the quantitative interpretation of DPM data into rock mechanics characteristics,such as uniaxial compressive strength,rock quality designation(RQD),and rock mass permeability,eliminating the need for subjective judgment normally involved in the currently used rock mass quality rating approaches. 展开更多
关键词 Drilling process monitoring Specific penetration index Specific energy index Fracture identification
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A Study on Penetration Strategies of Infectious Disease Prevention and Control Education in High School Biology Teaching
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作者 Yixun Zhang Yannan Liu +3 位作者 Yating Shi Tianyi Peng Jiahui Gao Shuiqin Shi 《Journal of Contemporary Educational Research》 2025年第2期16-22,共7页
The outbreak of COVID-19 pneumonia has had a serious impact on the world and has led to a greater awareness of the importance of infectious disease prevention and control.Biology is closely related to life sciences an... The outbreak of COVID-19 pneumonia has had a serious impact on the world and has led to a greater awareness of the importance of infectious disease prevention and control.Biology is closely related to life sciences and is an ideal discipline to penetrate infectious disease education.Conducting infectious disease prevention and control education can help increase students’knowledge of infectious disease prevention and control and prompt them to form good living habits. 展开更多
关键词 High school biology classroom Infectious disease prevention and control education Penetration education
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Recognition for underground voids in C-scans based on GMM-HMM
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作者 BAI Xu LI Yuhao +4 位作者 GUO Shizeng LIU Jinlong WEN Zhitao LI Hongrui ZHANG Jiayan 《Journal of Systems Engineering and Electronics》 2025年第1期82-94,共13页
Ground penetrating radar(GPR),as a fast,efficient,and non-destructive detection device,holds great potential for the detection of shallow subsurface environments,such as urban road subsurface monitoring.However,the in... Ground penetrating radar(GPR),as a fast,efficient,and non-destructive detection device,holds great potential for the detection of shallow subsurface environments,such as urban road subsurface monitoring.However,the interpretation of GPR echo images often relies on manual recognition by experienced engineers.In order to address the automatic interpretation of cavity targets in GPR echo images,a recognition-algorithm based on Gaussian mixed model-hidden Markov model(GMM-HMM)is proposed,which can recognize three dimensional(3D)underground voids automatically.First,energy detection on the echo images is performed,whereby the data is preprocessed and pre-filtered.Then,edge histogram descriptor(EHD),histogram of oriented gradient(HOG),and Log-Gabor filters are used to extract features from the images.The traditional method can only be applied to 2D images and pre-processing is required for C-scan images.Finally,the aggregated features are fed into the GMM-HMM for classification and compared with two other methods,long short-term memory(LSTM)and gate recurrent unit(GRU).By testing on a simulated dataset,an accuracy rate of 90%is obtained,demonstrating the effectiveness and efficiency of our proposed method. 展开更多
关键词 ground penetrating rader(GPR) RECOGNITION edge histogram descriptor(EHD) histogram of oriented gradient(HOG) Log-Gabor filter
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Clinical Observation of Curative Effect of Qingfei Ditan Decoction Combined with Targeted Drug Penetration Therapy of Traditional Chinese Medicine on Severe Mycoplasma Pneumonia in Children
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作者 Yanfang TAO Jianmin ZHANG +1 位作者 Xiukun WANG Jian PAN 《Medicinal Plant》 2025年第1期70-72,共3页
[Objectives]This study was conducted to explore the curative effect of Qingfei Ditan decoction combined with targeted drug penetration therapy of traditional Chinese medicine on severe mycoplasma pneumonia in children... [Objectives]This study was conducted to explore the curative effect of Qingfei Ditan decoction combined with targeted drug penetration therapy of traditional Chinese medicine on severe mycoplasma pneumonia in children.[Methods]Based on the retrospective study method,children with severe mycoplasma pneumonia admitted to the Children s Hospital of Soochow University from April 2023 to October 2023 were selected,and divided into a treatment group including 56 cases and a control group including 145 cases.The curative effect and adverse reactions of the two groups were compared.[Results]The total effective rate of the treatment group was higher than that of the control group,and the disappearance time of cough and lung rales was shorter than that of the control group,and the incidence of adverse reactions was lower,showing statistical significance(P<0.05).However,defervescence time and bronchoscope flushing rate showed no significant difference(P>0.05).[Conclusions]Qingfei Ditan Decoction combined with targeted drug penetration therapy of traditional Chinese medicine has a significant effect on severe mycoplasma pneumonia in children,and can reduce the side effects of drugs.It is a safe and efficient combination treatment scheme of traditional Chinese medicine. 展开更多
关键词 Qingfei Ditan Decoction Severe mycoplasma pneumonia in children Targeted drug penetration therapy of traditional Chinese medicine
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Second Near-Infrared Photothermal Therapy with Superior Penetrability through Skin Tissues 被引量:1
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作者 Yanji Chu Shenglong Liao +5 位作者 Hongguang Liao Yang Lu Xiaodong Geng Di Wu Jian Pei Yapei Wang 《CCS Chemistry》 CAS 2022年第9期3002-3013,共12页
Photothermal therapy(PTT)triggered by second near-infrared(NIR-II)light(1000–1400 nm)has shown great potential in tumor ablation because of its good tissue penetrability.However,NIR-II PTT still cannot treat tumors u... Photothermal therapy(PTT)triggered by second near-infrared(NIR-II)light(1000–1400 nm)has shown great potential in tumor ablation because of its good tissue penetrability.However,NIR-II PTT still cannot treat tumors underneath skin because of the light scattering effect of skin components.This research aims to promote the NIR-II penetrability of skin tissue by weakening the light scattering effect from the refractive index inhomogeneity among skin constituents. 展开更多
关键词 second near-infrared light photothermal therapy conjugated polymers tissue penetration light scattering
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Jet formation and penetration performance of a double-layer charge liner with chemically-deposited tungsten as the inner liner 被引量:2
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作者 Bihui Hong Wenbin Li +2 位作者 Yiming Li Zhiwei Guo Binyou Yan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期374-385,共12页
This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double... This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double-layer charge liners were fabricated by using CVD to deposit tungsten layers on the inner surfaces of pure T2 copper liners.The microstructures of the tungsten layers were analyzed using a scanning electron microscope(SEM).The feasibility analysis was carried out by pulsed X-rays,slug-retrieval test and static penetration tests.The shaped charge jet forming and penetration law of inner tungsten-coated double-layer liner were studied by numerical simulation method.The results showed that the double-layer liners could form well-shaped jets.The errors between the X-ray test results and the numerical results were within 11.07%.A slug-retrieval test was found that the retrieved slug was similar to a numerically simulated slug.Compared with the traditional pure copper shaped charge jet,the penetration depth of the double-layer shaped charge liner increased by 11.4% and>10.8% respectively.In summary,the test results are good,and the numerical simulation is in good agreement with the test,which verified the feasibility of using the CVD method to fabricate double-layer charge liners with a high-density and high-strength refractory metal as the inner liner. 展开更多
关键词 Shaped charge Chemical vapor deposition TUNGSTEN Double-layer charge liner X-ray PENETRATION
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Formation behaviors of rod-like reactive shaped charge penetrator and their effects on damage capability 被引量:1
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作者 Tao Sun Haifu Wang +4 位作者 Shipeng Wang Chao Ge Die Hu Pengwan Chen Yuanfeng Zheng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期242-253,共12页
Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical simulations.The pulsed X-ray technology and a spaced aluminu... Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical simulations.The pulsed X-ray technology and a spaced aluminum/steel plate with the thicknesses of 5 mm/100 mm are used.Three types of sphericalsegment aluminum-polytetrafluoroethylene-copper(Al-PTFE-Cu)reactive liners with Cu contents of 0%,46.6%,and 66%are fabricated and tested.The experimental results show that the reactive liners can form excellent rod-shaped penetrators with tail skirts under the shaped charge effect,but the tail skirts disappear over time.Moreover,rupturing damage to the aluminum plate and penetration to the steel plate are caused by the RRSCP impact.From simulation analysis,the RRSCP is formed by a mechanically and chemically coupled response with the reactive liner activated by shock in its outer walls and bottom and then backward overturning,forming a leading reactive penetrator and a following chemical energy cluster.The unique formation structure determines the damage modes of the aluminum plate and the steel plate.Further analysis indicates that the formation behaviors and damage capability of Al-PTFE-Cu RRSCP strongly depend on Cu content.With increasing Cu content,the velocity,activation extent,and reaction extent of Al-PTFE-Cu RRSCP decrease,which contribute to elongation and alleviate the negative effects of chemical reactions on elongation,significantly increasing the length-diameter ratio and thus enhancing the capability of steel plate penetration.However,the lower activation extent and energetic density will weaken the RRSCP's capability of causing rupturing damage to the aluminum plate. 展开更多
关键词 Reactive materials Al-PTFE composites Reactive liner X-ray PENETRATION
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Research on the influences of motion characteristics of jetting projectile charge under water 被引量:1
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作者 Xing Chen Yong-gang Lu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期411-425,共15页
Shaped charge warhead is important for enhancing the damage performance of underwater weapons.This paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of... Shaped charge warhead is important for enhancing the damage performance of underwater weapons.This 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 water.The 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 exponentially.Increasing the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the JPC.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 water.Material density plays a crucial role in the velocity decay pattern of the JPC during penetration.JPC with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are similar.Consequently,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge warhead.Finally,the results will provide an important reference for the design of underwater shaped charge warhead. 展开更多
关键词 JPC Movement characteristics Underwater penetration Numerical simulation
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High-speed penetration of ogive-nose projectiles into thick concrete targets:Tests and a projectile nose evolution model 被引量:1
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作者 Xu Li Yan Liu +4 位作者 Junbo Yan Zhenqing Shi Hongfu Wang Yingliang Xu Fenglei Huang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期553-571,共19页
The majority of the projectiles used in the hypersonic penetration study are solid flat-nosed cylindrical projectiles with a diameter of less than 20 mm.This study aims to fill the gap in the experimental and analytic... The majority of the projectiles used in the hypersonic penetration study are solid flat-nosed cylindrical projectiles with a diameter of less than 20 mm.This study aims to fill the gap in the experimental and analytical study of the evolution of the nose shape of larger hollow projectiles under hypersonic penetration.In the hypersonic penetration test,eight ogive-nose AerMet100 steel projectiles with a diameter of 40 mm were launched to hit concrete targets with impact velocities that ranged from 1351 to 1877 m/s.Severe erosion of the projectiles was observed during high-speed penetration of heterogeneous targets,and apparent localized mushrooming occurred in the front nose of recovered projectiles.By examining the damage to projectiles,a linear relationship was found between the relative length reduction rate and the initial kinetic energy of projectiles in different penetration tests.Furthermore,microscopic analysis revealed the forming mechanism of the localized mushrooming phenomenon for eroding penetration,i.e.,material spall erosion abrasion mechanism,material flow and redistribution abrasion mechanism and localized radial upsetting deformation mechanism.Finally,a model of highspeed penetration that included erosion was established on the basis of a model of the evolution of the projectile nose that considers radial upsetting;the model was validated by test data from the literature and the present study.Depending upon the impact velocity,v0,the projectile nose may behave as undistorted,radially distorted or hemispherical.Due to the effects of abrasion of the projectile and enhancement of radial upsetting on the duration and amplitude of the secondary rising segment in the pulse shape of projectile deceleration,the predicted DOP had an upper limit. 展开更多
关键词 High-speed penetration Concrete target EROSION Projectile nose evolution model
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