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Microcrack-and microvoid-related impact damage and ignition responses for HMX-based polymer-bonded explosives at high temperature

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Defence Technology（防务技术） 2022年第9期18卷 1602-1621页

作者： Hai-jiao Xue Yan-qing wu kun Yang Yi wu State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China School of Aerospace Engineering Beijing Institute of TechnologyBeijing100081China

Investigating the damage and ignition behaviors of polymer-bonded explosive(PBX) under a coupled impact and high-temperature loading condition is required for the safe use of charged PBXs. An improved combined microcrack and microvoid model(CMM) was developed for better describing the thermal effects of deformation, damage, and ignition responses of PBXs. The main features of the model under typical dynamic loadings(i.e. uniaxial tension and compression, and lateral confinement) at different initial temperature were first studied. And then the effects of temperature on impact-shear sensitivity of HMX-based PBXs were investigated. The results showed that the ignition threshold velocity of shear-crack hotspots exhibits an increase from 260 to 270 to 315-325 m/s when initial temperature increases from 301 to 348 K;and then the threshold velocity decreases to 290-300 m/s with the initial temperature continually increasing to 378 K. The predicted ignition threshold velocity level of the explosives under coupled impact and high temperature loading conditions were consistent with the experimental data.

关键词： PBX Thermal-mechanical coupling Numerical simulation Impact Sensitivity

Decreased AKAP4/PKA signaling pathway in high DFI sperm affects sperm capacitation

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Asian Journal of Andrology 2024年第1期26卷 25-33页

作者： kun Zhang Xiu-hua Xu Jian wu Ning Wang Gang Li Gui-Min Hao Jin-Feng Cao Hebei Key Laboratory of Infertility and Genetics Department of Reproductive MedicineSecond Hospital of Hebei Medical UniversityShijiazhuang 050000China Department of Reproductive Medicine Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221000China Department of Neurology The 980th Hospital of the People's Liberation Army Joint Logistics Support Force(Bethune International Peace Hospital)Shijiazhuang 050000China.

The sperm DNA fragmentation index(DFI)is a metric used to assess DNA fragmentation within *** in vitro fertilizationembryo transfer(IVF-ET),high sperm DFI can lead to a low fertilization rate,poor embryo development,early miscarriage,etc.A kinase anchoring protein(AKAP)is a scaffold protein that can bind protein kinase A(PKA)to subcellular sites of specific substrates and protects the biophosphorylation *** protein antigen 17(SPA17)can also bind to *** study intends to explore the reason for the decreased fertilization rate observed in high sperm DFI(H-DFI)patients during *** addition,the study investigates the expression of AKAP,protein kinase A regulatory subunit(PKARIl),and SPA17 between H-DFI and low sperm DFI(L-DFI)***17 at the transcriptional level is abnormal,the translational level increases in H-DFI patients,and the expression of AKAP4/PKARIl protein decreases.H,O,has been used to simulate oxidative stress damage to spermatozoa during the formation of sperm *** indicates that H,O,increases the expression of sperm SPA17 protein and suppresses AKAP4/PKARIl protein *** processes inhibit sperm capacitation and reduce acrosomal *** culture data and IVF outcomes have been *** H-DFI group has a lower fertilization ***,the results indicate that the possible causes for the decreased fertilization rate in the H-DFI patients have included loss of sperm AKAP4/PKARIl proteins,blocked sperm capacitation,and reduced occurrence of acrosome reaction.

关键词： AKAP PKA SPA17 sperm capacitation sperm DNA fragmentation index

Preface for Special Issue on“Key Mechanical Problems of Marine Energy Development Equipment”

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China Ocean Engineering 2022年第4期36卷 509-510页

作者： wu Wen-hua Faculty of Vehicle Engineering and Mechanics State Key Laboratory of Structural Analysis of Industrial EquipmentDalian University of TechnologyDalian 116024China Ningbo Institute of Dalian University of Technology Ningbo 315000China

There are abundant energy reserves such as oil,natural gas,hydrate,and wind energy in the *** around the globe are competing to advance their marine energy development *** exploitation of marine resources relies on cutting-edge industrial *** decades of R&D endeavors,China has obtained most of the key technologies for the design,production,testing,and field application of marine energy development equipment(Xie and Zeng,2021).

关键词： Key Mechanical Problems of Marine Energy Development Equipment Preface for Special Issue on

Tuning the interfacial reaction environment via pH-dependent and induced ions to understand C–N bonds coupling performance in NO3- integrated CO2 reduction to carbon and nitrogen compounds over dual Cu-based N-doped carbon catalyst

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Journal of Energy Chemistry 2025年第1期100卷 273-285页

作者： Tianhang Zhou Chen Shen Zhenghao wu Xingying Lan Yi Xiao College of Carbon Neutrality Future Technology State Key Laboratory of Heavy Oil Processing China University of Petroleum (Beijing) Institute of Materials Science TU Darmstadt Department of Chemistry Xi'an Jiaotong-Liverpool University Department of Mechanical and Mechatronics Engineering and Waterloo Institute of Nanotechnology University of Waterloo Waterloo

Dual atomic catalysts （DAC）,particularly copper （Cu2）-based nitrogen （N） doped graphene,show great potential to effectively convert CO2and nitrate （NO3-） into important industrial chemicals such as ethylene,glycol,acetamide,and urea through an efficient catalytical process that involves C–C and C–N ***,the origin of the coupling activity remained unclear,which substantially hinders the rational design of Cu-based catalysts for the N-integrated CO2reduction reaction （CO2RR）.To address this challenge,this work performed advanced density functional theory calculations incorporating explicit solvation based on a Cu2-based N-doped carbon (Cu2N6C10) catalyst for *** calculations are aimed to gain insight into the reaction mechanisms for the synthesis of ethylene,acetamide,and urea via coupling in the interfacial reaction *** to the sluggishness of CO2,the formation of a solvation electric layer by anions （F-,Cl-,Br-,and I-） and cations (Na+,Mg2+,K+,and Ca2+) leads to electron transfer towards the Cu *** process significantly accelerates the reduction of *** results reveal that*CO intermediates play a pivotal role in N-integrated ***,the Cu2-based N-doped carbon catalyst examined in this study has demonstrated the most potential for C–N coupling to *** findings reveal that through the process of a condensation reaction between*CO and NH2OH for urea synthesis,*NO3-is reduced to*NH3,and*CO2to*CCO at dual Cu atom *** dual-site reduction facilitates the synthesis of acetamide through a nucleophilic reaction between NH3and the ketene ***,we found that the I-and Mg2+ions,influenced by pH,were highly effective for acetamide and ammonia synthesis,except when F-and Ca2+were ***,the mechanisms of C–N bond formation were investigated via ab-initio molecular dynamics simulations,and we found that adjusting the micro-environment can change the dominant side reaction,shift

关键词： pH-dependent micro-environments C–N coupling Dual Cu-based nitrogen carbon catalysts Explicit solvation model Ion stabilizer AIMD

A New Pathway to Synthesize Cyclomercurated Ferrocenylimines Containing Heterocyclic Ring

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Chinese Chemical Letters 2003年第7期14卷 673-676页

作者： kun hua LIN Mao Ping SONG Chen Xia DU Qiao Hong ZHANG Yang Jie wu Department of Chemistry Zhengzhou UniversityHenan Key Laboratory of Applied ChemistryZhengzhou 450052

The cyclomercurated ferrocenylimines containing heterocyclic ring were prepared by the condensation of cyclomercuration of acylferrocene with the appropriate heterocyclic amine. This procedure provides an efficient method for the synthesis of cyclomerucurated ferroceny- limines containing heterocyclic ring which are difficultly synthesized by the conventional method. The reaction mechanism is proposed.

关键词： Heterocyclic ring containing cyclomercurated ferrocenylimine synthesis.

Identification of a nine-gene prognostic signature for gastric carcinoma using integrated bioinformatics analyses

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World Journal of Gastrointestinal Oncology 2020年第9期12卷 975-991页

作者： kun-Zhe wu Xiao-hua Xu Cui-Ping Zhan Jing Li Jin-Lan Jiang Scientific Research Center China-Japan Union Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Nephrology China-Japan Union Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Ultrasound China-Japan Union Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina

BACKGROUND Gastric carcinoma(GC)is one of the most aggressive primary digestive *** has unsatisfactory therapeutic outcomes and is difficult to diagnose *** To identify prognostic biomarkers for GC patients using comprehensive bioinformatics *** Differentially expressed genes(DEGs)were screened using gene expression data from The Cancer Genome Atlas and Gene Expression Omnibus databases for *** DEGs were analyzed using univariate and multivariate Cox regression analyses.A risk score model was then constructed and its prognostic value was validated utilizing an independent Gene Expression Omnibus dataset(GSE15459).Multiple databases were used to analyze each gene in the risk score ***-risk score-associated pathways and therapeutic small molecule drugs were analyzed and predicted,*** A total of 95 overlapping DEGs were found and a nine-gene signature(COL8A1,CTHRC1,COL5A2,AADAC,MAMDC2,SERPINE1,MAOA,COL1A2,and FNDC1)was constructed for the GC prognosis *** operating characteristic curve performance in the training dataset(The Cancer Genome Atlas-stomach adenocarcinoma)and validation dataset(GSE15459)demonstrated a robust prognostic value of the risk score *** database analyses for each gene provided evidence to further understand the nine-gene *** set enrichment analysis showed that the high-risk group was enriched in multiple cancer-related ***,several new small molecule drugs for potential treatment of GC were *** The nine-gene signature-derived risk score allows to predict GC prognosis and might prove useful for guiding therapeutic strategies for GC patients.

关键词： Gastric carcinoma Bioinformatic analysis Prognosis Overall survival Differentially expressed genes

Effects of aggregate size distribution and carbon nanotubes on the mechanical properties of cemented gangue backfill samples under true triaxial compression

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 311-324页

作者： Qian Yin Fan Wen Zhigang Tao Hai Pu Tianci Deng Yaoyao Meng Qingbin Meng Hongwen Jing Bo Meng Jiangyu wu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China State Key Laboratory for Geomechanics&Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China Key Laboratory of Xinjiang Coal Resources Green Mining Ministry of EducationXinjiang Institute of EngineeringUrumqi 830023China

The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious ***,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of *** mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically *** results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,***,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the ***σ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite ***ε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse *** increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.

关键词： cemented gangue backfill materials particle size distribution true triaxial compression test carbon nanotubes mechanical properties failure modes

Microstructure and Microhardness of Tempered Ni-Al Alloyed Layer

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Journal of Materials Science & Technology 2012年第10期28卷 937-940页

作者： Yue Yang hua wu College of Materials Science and Engineering Changchun University of TechnologyChangchun130012China

A Nd：YAG pulsed laser was used to alloy the Ni-P electroless deposited coating with aluminum substrate under the condition of scanning speed of 3.0 mm/s and power density of 5.36×10^9 W/m^2. Subsequently, the samples were heat treated at 300, 400 and 500 ℃ for 2.5 h, respectively. The phase composition and microstructure of the tempered layers treated at different temperature were identified by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. The results showed that the phase constituents of the alloyed zones were intermetallic compounds of NiAI, AI3Ni, Ni3P and AINi3. As a result, the microhardness of the alloyed layer after heat treatment was improved obviously compared to untreated samoles, and the laver obtained at teml0erature 400 ℃ reached HVn.1 430.

关键词： Laser alloying Nickel-aluminum intermetallics Heat treatment Microhardness

基于密度泛函理论研究Co、Ni、As掺杂载金黄铁矿的电子结构和稳定性

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原子与分子物理学报 2025年第1期42卷 145-155页

作者：吴德宝唐云李国辉吴波聂光华贵州大学矿业学院贵阳550025 贵州省非金属矿产资源综合利用重点试验室贵阳550025 紫金矿业集团股份有限公司龙岩364000

Co、Ni、As掺杂的黄铁矿晶体具有不同物理性质,会影响其载金性能和氧化行为.论文基于密度泛函理论计算,采用了CASTEP软件对载金黄铁矿以及不同晶体缺陷的载金黄铁矿进行模拟计算,以研究Co、Ni、As掺杂载金黄铁矿的电子结构,并据此分析... 详细信息

Co、Ni、As掺杂的黄铁矿晶体具有不同物理性质,会影响其载金性能和氧化行为.论文基于密度泛函理论计算,采用了CASTEP软件对载金黄铁矿以及不同晶体缺陷的载金黄铁矿进行模拟计算,以研究Co、Ni、As掺杂载金黄铁矿的电子结构,并据此分析其稳定性.综合半导体类型和能量分析,不同晶体缺陷的载金黄铁矿稳定性顺序为:Fe_(32)S_(63)AsAu

关键词：载金黄铁矿掺杂密度泛函理论氧化预处理

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