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高原环境爆炸冲击波传播规律及计算模型研究

火工品 2025年第1期 62-69页

作者：赵伟成翟红波李尚青毛伯永西安近代化学研究所陕西西安710065

为研究高原地区的低温低压环境对冲击波传播特性的影响,在海拔1500,3000,4500 m环境下开展了TNT爆炸试验,并使用有限元软件对高原环境TNT的爆炸冲击波进行数值仿真计算,分析了不同海拔对冲击波传播特性的影响规律。对比了Sadovskyi,Kinn... 详细信息

为研究高原地区的低温低压环境对冲击波传播特性的影响,在海拔1500,3000,4500 m环境下开展了TNT爆炸试验,并使用有限元软件对高原环境TNT的爆炸冲击波进行数值仿真计算,分析了不同海拔对冲击波传播特性的影响规律。对比了Sadovskyi,Kinney-Graham和Sachs修正公式的超压峰值和比冲量计算结果与试验结果,并采用Sachs修正中的温度修正项对Sadovskyi高原超压峰值公式进行了修正。研究结果表明:随着海拔的升高,冲击波的波阵面速度加快,到达时间提前,每升高1 km,冲击波超压峰值下降约2%~4%,比冲量下降约4%;对超压峰值进行修正时,3种修正公式均具有一定的准确性;对比冲量进行修正时,Kinney-Graham修正的比冲量值随比例距离增加呈线性降低,与试验结果吻合较差,庞春桥与Sachs的修正结果随比例距离增加呈指数降低;基于温度项修正的Sadovskyi高原冲击波超压峰值经验公式的平均误差减小了3.1%。该研究结果对于高海拔地区的弹药毁伤效能评估有参考意义。

关键词：爆炸试验高原环境冲击波传播特性计算模型

Deformation behavior and microstructural evolution during hot compression of an a+b Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 344-351页

作者： Gao-feng liu shang-zhou Zhang li-qing Chen Jian-xun Qiu School of Environmental and Materials Engineering Yantai University Yantai 264005 China State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 China

The effect of processing parameters on the flow response and microstructural evolution of the a＋b titanium alloy Ti-6.5Al-3.5Mo-1.5Zr-0.3Si has been studied by conducting isothermal hot compressive tests at a strain rate of 0.01-10 s-1 at 860-1100°C. The true stress-true strain curves of the sample hot-compressed in the a＋b phase region exhibit a peak stress followed by continuous flow softening, whereas in the b region, the flow stress attains a steady-state regime. At a strain rate of 10 s-1, the alloy exhibits plastic flow insta-bilities. According to the kinetic rate equation, the apparent activation energies are estimated to be about 674-705 kJ/mol in the a＋b region and 308-335 kJ/mol in the b region, respectively. When deformed in the a＋b region, the globularization process of the a colony structure occurs, and a dynamic recrystallized microstructures are observed to show bimodal. Dynamic recrystallization can take place in the b region irrespective of starting deformed structures.

关键词： titanium alloys hot pressing deformation microstructural evolution activation energy

Dense Face Network:A Dense Face Detector Based on Global Context and Visual Attention Mechanism

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Machine Intelligence Research 2022年第3期19卷 247-256页

作者： lin Song Jin-Fu Yang qing-Zhen shang Ming-Ai li Faculty of Information Technology Beijing University of TechnologyBeijing 100124China Beijing Key Laboratory of Computational Intelligence and Intelligent Systems Beijing 100124China

Face detection has achieved tremendous strides thanks to convolutional neural networks. However, dense face detection remains an open challenge due to large face scale variation, tiny faces, and serious occlusion. This paper presents a robust, dense face detector using global context and visual attention mechanisms which can significantly improve detection accuracy. Specifically, a global context fusion module with top-down feedback is proposed to improve the ability to identify tiny faces. Moreover, a visual attention mechanism is employed to solve the problem of occlusion. Experimental results on the public face datasets WIDER FACE and FDDB demonstrate the effectiveness of the proposed method.

关键词： Face detection global context attention mechanism computer vision deep learning

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雾视法在成年人近视验光配镜中的应用探讨

国际眼科杂志 2008年第2期8卷 400-402页

作者：苟胜文尚清丽高菊荣马建洲解放军第323医院眼科中国陕西省西安市710054

目的:为了解雾视法对部分成年人近视验光的结果影响情况,确定门诊对成年人中低度近视进行验光时应用此法的优点。方法:门诊选取成年人(21～45岁)52例104眼,裂隙灯、眼底镜检查排除感染、干眼症、青光眼、白内障、眼底等影响视力疾病。... 详细信息

目的:为了解雾视法对部分成年人近视验光的结果影响情况,确定门诊对成年人中低度近视进行验光时应用此法的优点。方法:门诊选取成年人(21～45岁)52例104眼,裂隙灯、眼底镜检查排除感染、干眼症、青光眼、白内障、眼底等影响视力疾病。先后进行裸眼远近视力、自然瞳孔下电脑自动验光,带状光检影验光、插片试镜,然后雾视,再进行相同检查。比较前后裸眼视力、自然瞳孔下电脑自动验光,带状光检影验光结果、主观插片矫正度数。结果:雾视前后的裸眼视力、检影结果,电脑自动验光及插片矫正度数均有显著性差异。结论:各种验光方法结果均有差异。成年人近视眼在门诊进行验光时,采取雾视法后,进行检影验光,电脑验光和主观插片验光可获得较为可靠,客观的验光结果。

关键词：近视验光雾视法

A comparative study of four nonlinear dynamic methods and their applications in classification of ship-radiated noise

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Defence Technology（防务技术） 2022年第2期18卷 183-193页

作者： Yu-xing li shang-bin Jiao Bo Geng qing Zhang You-min Zhang School of Automation and Information Engineering Xi’an University of TechnologyXi’an710048China Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi’an University of TechnologyXi’an710048China Department of Mechanical Industrial and Aerospace EngineeringConcordia UniversityMontrealQuebec H3G 1M8Canada

Refined composite multi-scale dispersion entropy(RCMDE),as a new and effective nonlinear dynamic method,has been applied in the field of medical diagnosis and fault *** this paper,we first introduce RCMDE into the field of underwater acoustic signal processing for complexity feature extraction of ship radiated noise,and then propose a novel classification method for ship-radiated noise based on RCMDE and k-nearest neighbor(KNN),termed *** results of a comparative experiment show that the proposed RCMDE-KNN classification method can effectively extract the complexity features of ship-radiated noise,and has better classification performance under one and two scales than the other three classification methods based on multi-scale permutation entropy(MPE)and KNN,multi-scale weighted-permutation entropy(MW-PE)and KNN,and multi-scale dispersion entropy(MDE)and KNN,termed MPE-KNN,MW-PE-KNN,and *** is proved that the RCMDE-KNN classification method for ship-radiated noise is feasible and effective,and can obtain a very high recognition rate.

关键词： Nonlinear dynamic Refined composite multi-scale dispersion entropy(RCMDE) Multi-scale dispersion entropy(MDE) Multi-scale weighted-permutation entropy (MW-PE) Multi-scale permutation entropy(MPE) Classification of ship-radiated noise

Construction of 3D porous Cu_(1.81)S/nitrogen-doped carbon frameworks for ultrafast and long-cycle life sodium-ion storage

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 191-200页

作者： Chen Chen Hongyu Xue Qilin Hu Mengfan Wang Pan shang Ziyan liu Tao Peng Deyang Zhang Yongsong Luo Key Laboratory of Microelectronics and Energy of Henan Province Henan Joint International Research Laboratory of New Energy Storage TechnologyCollege of Physics and Electronic EngineeringXinyang Normal UniversityXinyang 464000China School of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific ***,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs ***,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for ***,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 *** work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.

关键词： copper sulfide nanoparticles porous carbon framework fast charging long-cycle performance sodium-ion full batteries

The Strategies of Pathogen-Oriented Therapy on Circumventing Antimicrobial Resistance

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Research 2020年第1期2020卷 238-269页

作者： Zifang shang Siew Yin Chan qing Song Peng li Wei Huang Frontiers Science Center for Flexible Electronics(FSCFE) Xi’an Institute of Flexible Electronics(IFE)&Xi’an Institute of Biomedical Materials and Engineering(IBME)Northwestern Polytechnical University(NPU)Xi’an 710072China Key Laboratory for Organic Electronics and Information Displays(KLOEID)and Institute of Advanced Materials(IAM) Nanjing University of Posts and Telecommunications(NUPT)Nanjing 210023China Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing Tech University(NanjingTech)Nanjing 211816China

The emerging antimicrobial resistance(AMR)poses serious threats to the global public *** antibiotics have been eclipsed in combating with drug-resistant ***,the developing and deploying of novel antimicrobial drugs have trudged,as few new antibiotics are being developed over time and even fewer of them can hit the *** therapeutic strategies to resolve the AMR crisis are urgently ***-oriented therapy(POT)springs up as a promising approach in circumventing antibiotic *** tactic underling POT is applying antibacterial compounds or materials directly to infected regions to treat specific bacteria species or strains with goals of improving the drug efficacy and reducing nontargeting and the development of drug *** review exemplifies recent trends in the development of POTs for circumventing AMR,including the adoption of antibiotic-antibiotic conjugates,antimicrobial peptides,therapeutic monoclonal antibodies,nanotechnologies,CRISPR-Cas systems,and microbiota *** these alternative approaches alone or in combination shows promising advantages for addressing the growing clinical embarrassment of antibiotics in fighting drug-resistant bacteria.

关键词： drugs fighting alone

Genetic diversity and population structure of Camellia huana(Theaceae),a limestone species with narrow geographic range,based on chloroplast DNA sequence and microsatellite markers

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Plant Diversity 2020年第5期42卷 343-350页

作者： Shuang li shang-li liu Si-Yu Pei Man-Man Ning Shao-qing Tang Guangxi Key Laboratory of Rare and Endangered Animal Ecology College of Life ScienceGuangxi Normal UniversityGuilinChina Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection Ministry of EducationGuangxi Normal UniversityGuilinChina Longtan Nature Reserve Management Center HechiChina College of life Science Guangxi Normal UniversityGuilinGuangxi 541006China

Camellia huana is an endangered species with a narrow distribution in limestone hills of northern Guangxi and southern Guizhou provinces,*** used one chloroplast DNA(cpDNA)fragment and 12 pairs of microsatellite(simple sequence repeat;SSR)markers to assess the genetic diversity and structure of 12 *** populations.A total of 99 alleles were detected for 12 polymorphic loci,and eight haplotypes and nine polymorphic sites were detected within 5200 bp of *** populations showed a low level of genetic diversity(n=8,Hd=0.759,Pi=0.00042 for cpDNA,NA=3.931,HE=0.466 for SSRs),but high genetic differentiation between populations(FST=0.2159 for SSRs,FST=0.9318 for cpDNA).This can be attributed to the narrow distribution and limestone habitat of *** analysis divided natural *** populations into two groups,consistent with their geographical ***,we suggest that five natural *** populations should be split into two units to be managed effectively.

关键词： Camellia huana Genetic diversity Genetic structure Conservation implications

Effect of biochar application on rice,wheat,and corn seedlings in hydroponic culture

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Journal of Environmental Sciences 2024年第1期135卷 379-390页

作者： Yingjie Yin Jikai li Sihang Zhu qing Chen Chong Chen Yukui Rui Jianying shang College of Land Science and Technology China Agricultural UniversityKey Laboratory of Plant-Soil InteractionsMinistry of Educationand Key Laboratory of Arable Land Conservation in North ChinaMinistry of Agriculture and Rural AffairsBeijing 100193China Agricultural Management Institute Ministry of Agriculture and Rural AffairsBeijing 102208China College of Resources and Environmental Sciences China Agricultural UniversityBeijing Key Laboratory of Farmland Soil Pollution Prevention and RemediationBeijing 100193China

In recent years,biochar has attracted considerable attention for soil quality improvement and carbon sequestration due to its unique physicochemical ***,the mechanism by which biochar application negatively affects the growth of crop seedlings has not been fully *** this study,a hydroponic experiment was conducted to evaluate the response of rice,wheat,and corn seedlings to biochar application(CK,0 g/L;BC1,0.5 g/L;and BC2,1.0 g/L).Compared with the CK treatment,the BC1 and BC2 treatments decreased the fresh shoot and root weights of rice and corn seedlings(Plings(P>0.05).For the contents of nutrient elements in seedlings,both BC1 and BC2 treatments hindered the roots from absorbing Fe and Cu and increased the uptake of Ca and *** with the CK treatment,the translocation factor(TF)values of Ca,Mn,and Zn were significantly decreased especially in rice seedlings(35.3%-36.8%,68.7%-76.5%,and 29.8%-22.0%,respectively)under the BC1 and BC2 treatments,while only Mn was significantly decreased in wheat and corn seedlings(Plication can reduce nutrient absorption and translocation,and hinder rice,wheat,and corn seedlings,particularly rice seedling,in hydroponic system.

关键词： Biochar Toxicity Seedling growth Hydroponic cultivation