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Experimental study on explosion dispersion process of a multi-layer composite charge under different initiation modes

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Defence Technology（防务技术） 2020年第4期16卷 883-892页

作者： xiao-wen hong Wei-bing Li wen-bin Li He-yang Xu Bo-liang Wang Wei xiao ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjingPR China School of Chemical Engineering Nanjing University of Science and TechnologyNanjingPR China

The influe nce of initiation modes on the explosive dispersion process of the multi-layer co mposite charge(MCC) was *** sensors and high-speed photography system were used to investigate the energy release process of an MCC with a specific *** shock wave pressure and explosive dispersion characteristics of the MCC under different initiation modes were *** forming and expanding process of the shock wave of the composite charge under different initiation modes was *** separation position of the shock wave and fireball interface was *** calculation formulas of the shock radius and overpressure of the composite charge are *** radius of the shock wave of the composite charge was significantly affected by the initiation ***,the development process of the composite explosive fireball under different initiation modes was analyzed,the variation rules of the composite charge dispersion radius and fireball dispersion velocity with time were obtained under the different initiation modes,the explosion energy release rate of composite charge under simultaneous initiation modes was the highest,and the peak overpressure under the simultaneous initiation mode was 1.61 times that of central single-point initiation.

关键词： Composite charge Initiation mode Blast wave Overpressure Dispersion radius

Numerical simulation of the blast wave of a multilayer composite charge

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Defence Technology（防务技术） 2020年第1期16卷 96-106页

作者： xiao-wen hong Wei-bing Li Wei Cheng wen-bin Li He-yang Xu ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjingPR China Chongqing hongyu Precision Industrial Co. LtdChongqingPR China

The numerical simulation of a blast wave of a multilayer composite charge is investigated.A calculation model of the near-field explosion and far-field propagation of the shock wave of a composite charge is established using the AUTODYN finite element *** of the near-field and far-field calculations of the shock wave respectively converge at cell sizes of 0.25-0.5 cm and 1-3 *** Euler--fluxcorrected transport solver is found to be suitable for the far-field calculation after mapping.A numerical simulation is conducted to study the formation,propagation,and interaction of the shock wave of the composite charge for different initiation *** is found that the initiation mode obviously affects the shock-wave waveform and pressure distribution of the composite ***,it is found that the area of the overpressure distribution is greatest for internal and external simultaneous initiation,and the peak pressure of the shock wave exponentially decays,fitting the calculation formula of the peak overpressure attenuation under different initiation modes,which is obtained and verified by *** difference between numerical and experimental results is less than 10%,and the peak overpressure of both internal and external initiation is 56.12% higher than that of central single-point initiation.

关键词： Structure of composite charge Initiation mode Blast wave Cell size in calculation Numerical simulation

Fracture mechanism of a cylindrical shell cut by circumferential detonation collision

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Defence Technology（防务技术） 2021年第5期17卷 1650-1659页

作者： He-yang Xu Wei-bing Li wen-bin Li Qing Zhang Ya-jun Wang xiao-wen hong Ying Yang Nanjing University of Science and Technology Nanjing210094China Jiangsu Yongfeng Mechanics Co. LtdNanjing210094China

The failure mechanism of a cylindrical shell cut into fragments by circumferential detonation collision was experimentally and numerically investigated.A self-designed detonation wave regulator was used to control the detonation and cut the *** was found that the self-designed regulator controlled the fragment *** macrostructure and micro-characteristics of fragments revealed that shear fracture was a prior mechanism,the shell fractured not only at the position of detonation collision,but the crack also penetrated the shell at the first contact position of the Chapmen-Jouguet(C-J)*** effects of groove number and outer layer thickness on the fracture behavior were tested by *** the thickness of the outer layer was 5e18 mm,it has little effect on fragmentation of the shell,and shells all fractured at similar *** increase of the groove number reduced the fracture possibility of the first contact position of the C-J *** the groove number reached 7 with a 10 mm outer layer(1/4 model),the fracture only occurred at the position of detonation collision and the fragment width rebounded.

关键词： Detonation wave Circumferential detonation collision Fracture mechanism Fragmentation control

Blast wave characteristics of multi-layer composite charge:Theoretical analysis,numerical simulation,and experimental validation

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Defence Technology（防务技术） 2023年第1期19卷 91-102页

作者： Jun-bao Li Wei-bing Li xiao-wen hong Jia-xin Yu Jian-jun Zhu ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjing210094China Inner Mongolia Metal Material Research Institute Yantai264003China China Ship Development and Design Center Wuhan 430064China

This article investigates the characteristics of shock wave overpressure generated by multi-layer composite charge under different detonation *** dimensional analysis and the explosion mechanism of the charge,a peak overpressure prediction model for the composite charge under singlepoint detonation and simultaneous detonation was *** effects of the charge structure and initiation method on the overpressure field characteristics were investigated in AUTODYN *** accuracy of the prediction model and the reliability of the numerical simulation method were subsequently verified in a series of static explosion *** results reveal that the mass of the inner charge was the key factor determining the peak overpressure of the composite charge under single-point *** peak overpressure in the radial direction improved apparently with an increase in the aspect ratio of the *** overpressure curves in the axial direction exhibited a multi-peak phenomenon,and the secondary peak overpressure even exceeded the primary peak at distances of 30D and 40D(where D is the charge diameter).The difference in peak overpressure among azimuth angles of 0-90°gradually decreased with an increase in the propagation distance of the shock *** coupled effect of the detonation energy of the inner and outer charge under simultaneous detonation improved the overpressure in both radial and axial *** difference in peak overpressure obtained from model prediction and experimental measurements was less than 16.4%.

关键词： Blast wave characteristics Multi-layer composite charge Dimensional analysis AUTODYN mapping Model Explosion experiment

Quantitative (stereological) study on the spermatozoal storage capacity of epididymis in rats and monkeys

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Asian Journal of Andrology 2000年第1期2卷 73-77页

作者： xiao-hong wen Zheng-Wei YANG Morphometric Research Laboratory, North Sichuan Medical College, Nanchong 637007, China. Morphometric Research Laboratory North Sichuan Medical College 234 Fujiang Road Nanchong 637007 China

Aim: To investigate the spermatozoal production rate of the testis and the spermatozoal storage capacity of the epi-didymis in monkeys and rats. Methods: The number of the late spermatids (steps 13 - 14 in the monkey or steps15 - 19 in the rat) per testis and the number of spermatozoa per epididymis were estimated in 6 normal adult monkeys(Macaca fascicularis) and 6 normal adult SD rats on 25 um-thick methacrylate-embedded sections using a contempo-rary unbiased and efficient stereological method-the optical disector. The diameter and length of the efferent ductulesand ductus epididymidis and the volume of the epididymal fluid in the tubules were also estimated. Results: The totalnumber of the late spermatids per testis was 2902 ±749 (million, x ±s) in the monkey, or 179 ±31 in the rat; thenumber of spermatozoa per epididymis was 3235 ±1835 in the monkey, or 241±76 in the rat. Conclusion: A largenumber of spermatozoa was densely packed and stored in the ductus epididymidis; the epididymal transit time for sper-matozoa was around 5 days in monkeys or 11 days in rats.

关键词： epididymis spermatids spermatozoa stereology testis

Addition of ulinastatin to preservation solution promotes protection against ischemia-reperfusion injury in rabbit lung

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Chinese Medical Journal 2011年第14期124卷 2179-2183页

作者： XU Ming wen xiao-hong CHEN Shu-ping AN xiao-xia XU He-yun Department of Anesthesiology First Affiliated Hospital Zhejiang University School of Medicine HangzhouZhejiang 310003 China Department of Anesthesiology Hangzhou First People's HospitalHangzhou Zhejiang 310006 China Department of Cardiothoracic Surgery First Affiliated Hospital Zhejiang University School of Medicine HangzhouZhejiang 310003 China

Background The composition of the lung preservation solution used in lung graft procurement has been considered the key to minimize lung injury during the period of ischemia. Low-potassium dextran glucose （LPDG）, an extracellular-type solution, has been adopted by most lung transplantation centers, due to the experimental and clinical evidences that LPDG is superior to intracellular-type solutions. Ulinastatin has been shown to attenuate ischemia-reperfusion （I/R） injury in various organs in animals. We supposed that the addition of ulinastatin to LPDG as a flushing solution, would further ameliorate I/R lung injury than LPDG solution *** Twelve male New Zealand white rabbits were randomly divided into 2 groups. Using an alternative in situ lung I/R model, the left lung in the control group was supplied and preserved with LPDG solution for 120 minutes. In the study group 50 000 U/kg of ulinastatin was added to the LPDG solution for lung preservation. Then re-ventilation and reperfusion of the left lung were performed for 90 minutes. Blood gas analysis （PaO2, PaCO2）, mean pulmonary artery pressure （MPAP） and serum TNF-α level were measured intermittently. The pulmonary water index （D/W）, tissue myeloperoxidase （MPO） activity, tissue malondialdehyde （MDA） content and morphologic changes were *** The study group showed significantly higher PaO2 and lower MPAP at the end of reperfusion. Serum TNF-α level, left lung tissue MPO and MDA in the study group were significantly lower than those in the control group. D/W and pathologic evaluation were also remarkably different between the two *** This study indicated that better lung preservation could be achieved with the use of an ulinastatin modified LPDG solution. Ulinastatin further attenuated lung I/R injury, at least partly by reducing oxidative reactions,inhibiting the release of inflammatory factors and neutrophils immigration.

关键词： ischemia reperfusion injury organ preservation lung LPDG solution ulinastatin urinary trypsin inhibitor rabbits

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Father Remarries

Women of China 1996年第5期 17-18页

作者： xiao wen hong X.LIU

FATHER seemed a different person after my mother’s death. During my frequent visits home I noticed that he stayed in one place for a long time, silently, but sighing all the time. As time went by I visited home less often, mostly because of the pressures of my job. My father called and complained that he had no one to talk to, that he

关键词： Father Remarries

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语言习得与语法教学

汉语学习 2008年第1期 76-84页

作者：温晓虹休士顿大学语言系

语言习得研究的一个主要方面是语法规则的习得。语法知识的建立分为两种:一种是在交流时无意识形成的;另一种是能明确说出来的。本文提出教师要通过大量的有特征性的语言输入来促使学生把语言规则提炼出来,再融入到自己的语言系统中,使... 详细信息

语言习得研究的一个主要方面是语法规则的习得。语法知识的建立分为两种:一种是在交流时无意识形成的;另一种是能明确说出来的。本文提出教师要通过大量的有特征性的语言输入来促使学生把语言规则提炼出来,再融入到自己的语言系统中,使之不断地趋于目的语。这种教授语法的理念不同于传统的语法教学,有益于促进学习者中介语系统的发展,通过对语言形式的练习来促进学习者对语言特征的注意,使语言经验概念化,学习者能创造性地运用语言。这种语法教学是在语言交际的前提下进行的。本文以课堂活动设计实例来说明这一观点。

关键词：语言习得中介语交际能力任务型活动

A temporary-sustainable team:A new multidisciplinary team model for severe trauma

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Chinese Journal of Traumatology 2020年第6期23卷 363-366页

作者： Xing-Ming Zhong xiao-hong wen Chao-Hui Ji Xing-Zhen Fei xiao-Gang Zhao Department of Emergency and Department of Neurosurgery The First People's Hospital of HuzhouFirst Affiliated Hospital of Huzhou Normal UniversityHuzhou 313000Zhejiang ProvinceChina Department of Emergency The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

The treatment of severe trauma,especially multiple injuries,requires multidisciplinary *** current study aims to highlight the challenges of consultation mode for severe trauma in general hospitals and emphasizes the need to create a new temporary-sustainable *** suggests developing an information consultation mode and enforcing the fine management to improve the quality and safety of the medical *** management mode of a temporary-sustainable team will reduce the cost and improve the treatment ***,a temporary-sustainable team has significant advantages over a traditional multidisciplinary team for severe trauma treatment.

关键词： Trauma Temporary-sustainable team Multidisciplinary team