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Simulation of two-dimensional interior ballistics model of solid propellant electrothermal-chem ical launch with discharge rod plasma generator

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Defence Technology（防务技术） 2017年第4期13卷 249-256页

作者： Yan-jie Ni Yong Jin Niankai Cheng chun-xia yang Hai-yuan Li Bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and Technology Nanjing 210094 Jiangsu China China Academy of Ordnance 100089 Beijing China

Instead of the capillary plasma generator(CPG),a discharge rod plasma generator(DRPG)is used in the30 mm electrothermal-chemical(ETC)gun to improve the ignition uniformity of the solid *** axisymmetric two-dimensional interior ballistics model of the solid propellant ETC gun(2D-IB-SPETCG)is presented to describe the process of the ETC *** calculated pressure and projectile muzzle velocity accord well with the experimental *** feasibility of the 2D-IB-SPETCG model is *** on the experimental data and initial parameters,detailed distribution of the ballistics parameters can be *** the distribution of pressure and temperature of the gas phase and the propellant,the influence of plasma during the ignition process can be *** of the radial flowing plasma,the propellant in the area of the DRPG is ignited within 0.01 ms,while all propellant in the chamber is ignited within 0.09 *** radial ignition delay time is much less than the axial delay *** the ignition process,the radial pressure difference is less than 5 MPa at the place 0.025 m away from the *** radial ignition uniformity is *** temperature of the gas increases from several thousand K(conventional ignition)to several ten thousand K(plasma ignition).Compare the distribution of the density and temperature of the gas,we know that low density and high temperature gas appears near the exits of the DRPG,while high density and low temperature gas appears at the wall near the *** simulation of the 2D-IB-SPETCG model is an effective way to investigate the interior ballistics process of the ETC *** 2D-IB-SPETC model can be used for prediction and improvement of experiments.

关键词： Electrothermal-chemical launch Interior ballistics simulation Two-phase flow Two-dimensional model

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生物医药厂房结构施工安全风险管控

建筑技术开发 2024年第3期51卷 145-147页

作者：陆万柱朱朝聪陈伟夏春阳中建科技集团有限公司深圳分公司广东深圳518118

以坪山生物医药产业加速器园区项目结构施工为例,针对装配式群体结构在施工过程中主要存在的安全隐患进行了识别和判断,介绍了相应的安全管理措施和创新技术,主要包括群塔作业及各类安全防护措施。经项目实际应用,采用的管理措施和技术... 详细信息

以坪山生物医药产业加速器园区项目结构施工为例,针对装配式群体结构在施工过程中主要存在的安全隐患进行了识别和判断,介绍了相应的安全管理措施和创新技术,主要包括群塔作业及各类安全防护措施。经项目实际应用,采用的管理措施和技术手段,在满足现场安全施工的前提下,达到了节约成本的功效。在施工过程中大体量地使用装配式施工技术,实现了已使用的材料可达到多次周转使用的目的,具有绿色环保、安全可靠等特点,更好地保证了本工程施工的顺利进行,可为类似工程提供借鉴。

关键词：装配式结构风险分类安全管理与创新

Electrochemical study and application on rutin at chitosan/graphene films modified glassy carbon electrode

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Journal of Pharmaceutical Analysis 2013年第2期3卷 102-108页

作者： Jing An Ying-Yan Bi chun-xia yang Fang-Di Hu chun-Ming Wang School of Pharmacy Lanzhou University College of Chemistry and Chemical Engineering Lanzhou University

Graphene（G） was dispersed into 0.5% chitosan（Chit） solution,then the composite films were coated on glassy carbon electrode（GCE）,the electrochemical behavior of rutin on a Chit/G modified GCE was investigated and the electrochemical parameters of rutin were *** effectively accumulated on the Chit/G/GCE and caused a pair of redox peaks at around 408 mV and 482 mV（***） in 0.1M phosphate buffer solution（pH 4.0）.Under optimized conditions,the anodic peak current was linear to the rutin concentration in the range of 5×107-1.04×*** regression equation was：y 9.9219x-0.0025,r=*** proposed method was successfully used for the determination of rutin content in tablet samples with satisfactory results.

关键词： Electrochemical Chitosan/graphene films Differential pulse voltammetry Rutin

Application of transient burning rate model of solid propellant in electrothermal-chemical launch simulation

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Defence Technology（防务技术） 2016年第2期12卷 81-85页

作者： Yan-jie NI Yong JIN Gang WAN chun-xia yang Hai-yuan LI Bao-ming LI National Key Laboratory of Transient Physics Nanjing University of Science and Technology

A 30 mm electrothermal-chemical(ETC) gun experimental system is employed to research the burning rate characteristics of 4/7 high-nitrogen solid propellant. Enhanced gas generation rates(EGGR) of propellants during and after electrical discharges are verified in the experiments. A modified 0D internal ballistic model is established to simulate the ETC launch. According to the measured pressure and electrical parameters, a transient burning rate law including the influence of EGGR coefficient by electric power and pressure gradient(dp/dt) is added into the model. The EGGR coefficient of 4/7 high-nitrogen solid propellant is equal to 0.005 MW-1. Both simulated breech pressure and projectile muzzle velocity accord with the experimental results well. Compared with Woodley's modified burning rate law, the breech pressure curves acquired by the transient burning rate law are more consistent with test results. Based on the parameters calculated in the model, the relationship among propellant burning rate, pressure gradient(dp/dt) and electric power is analyzed. Depending on the transient burning rate law and experimental data, the burning of solid propellant under the condition of plasma is described more accurately.

关键词：固体推进剂内弹道模型发射模拟电热化学燃速特性瞬态燃烧速率应用

Design and manufacture of a 100 kA coaxial pulsed power cable for plasma generator and PPS in ETC guns

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Defence Technology（防务技术） 2019年第5期15卷 698-702页

作者： Yong Jin Zhen-xiao Li Yan-jie Ni xiao-ya Gao Gang Wan chun-xia yang Bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing 210094China Information Central of China North Industries Group Corporation Beijing100089China China Academy of Ordnance Beijing100089China

Based on our previous pulsed current and internal overvoltage test data and the experience of common commercial high power cables,a 100 kA coaxial pulsed power cable is designed and manufactured to adapt the coaxial electric energy breech transmission between the plasma generator and the pulsed power supply(PPS) in electrothermal-chemical(ETC) *** index parameters are analyzed and ***-conductor layers and a shield stiffener are introduced to prevent the deformation and burst of the pulsed power cable *** semi-conductor layer can eliminate the air gap and balance the electric field in the *** shield stiffener can multiply the mechanical strength to restrain the strong electrodynamic force produced by the core dislocation of the outer *** multi-coupling of electromagnetic field,stress field and thermal field analysis are established to assist in aided design of electrical strength,mechanical strength and temperature rise *** a DC voltage withstand test and pulsed discharge tests are introduced to verify and inspect the performance and dynamic response of the pulsed power *** 25 kV/5 min DC voltage withstand test result shows that the sample leakage current is nearly 3 μA and no abnormal phenomena of the pulsed power cable sample *** pulsed discharge tests show that the sample can sustain the 100 kA peak ***,this 100 kA coaxial pulsed power cable can satisfy the ETC test requirements.

关键词： Pulsed power cable Pulsed power supply Electrothermal-chemical launch Coaxial structure

Numerical analysis of hydraulic fracture propagation in deep shale reservoir with different injection strategies

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3558-3574页

作者： Yingjie xia Mingyu Yao Tianjiao Li Hai yang chun'an Tang School of Civil Engineering Dalian University of TechnologyDalian116024China Deep Underground Engineering Research Center Dalian University of TechnologyDalian116024China CNPC Chuanqing Drilling Engineering Company Limited Chengdu610051China

Deep shale reservoirs are characterized by elevated breakdown pressures,diminished fracture complexity,and reduced modified volumes compared to medium and shallow ***,it is urgent to investigate particular injection strategies that can optimize breakdown pressure and fracturing efficiency to address the increasing demands for deep shale reservoir *** this study,the efficiency of various stimulation strategies,including multi-cluster simultaneous fracturing,modified alternating fracturing,alternating shut-in fracturing,and cyclic alternating fracturing,was ***,the sensitivity of factors such as the cycle index,shut-in time,cluster spacing,and horizontal permeability was ***,the flow distribution effect within the wellbore was *** results indicate that relative to multi-cluster simultaneous fracturing,modified alternating fracturing exhibits reduced susceptibility to the stress shadow effect,which results in earlier breakdown,extended hydraulic fracture lengths,and more consistent propagation despite an increase in breakdown *** alternating shut-in fracturing benefits the increase of fracture length,which is closely related to the shut-in ***,cyclic alternating fracturing markedly lowers breakdown pressure and contributes to uniform fracture propagation,in which the cycle count plays an important *** alternating fracturing demonstrates insensitivity to variations in cluster spacing,whereas horizontal permeability is a critical factor affecting fracture *** wellbore effect restrains the accumulation of pressure and flow near the perforation,delaying the initiation of hydraulic *** simulation results can provide valuable numerical insights for optimizing injection strategies for deep shale hydraulic fracturing.

关键词： Fracture propagation Numerical simulation Hydraulic fracturing Rock failure process analysis(RFPA) Injection strategy

Congenital leukemia: A case report and review of literature

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World Journal of Clinical Cases 2023年第29期11卷 7227-7233页

作者： chun-xia yang Ying yang Fen-Li Zhang Ding-Huan Wang Qiu-Han Bian Man Zhou Ming-xiang Zhou xiao-Yan yang Department of Pediatrics Affiliated Hospital of Guizhou Medical UniversityGuiyang 550000Guizhou ProvinceChina Clinical Medicine Guizhou Medical UniversityGuiyang 550000Guizhou ProvinceChina

BACKGROUND Acute leukemia in newborns is also known as neonatal or congenital leukemia(CL)and is a rare disease with an incidence rate of 1-5 per 1000000 live *** birth,infants with CL exhibit infiltrative cutaneous nodules,hepatosplenomegaly,thrombocytopenia,and immature leukocytes in the peripheral *** symptoms are frequently accompanied by congenital abnormalities including trisomy 21,trisomy 9,trisomy 13,or Turner *** significant advances in disease management,the survival rate is approximately 25%at 2 *** SUMMARY Here,we document a case of trisomy 21-related acute myeloid leukemia(AML)in a female *** baby was sent to the neonatal intensive care unit because of anorexia,poor responsiveness,and respiratory *** was diagnosed with AML based on bone marrow aspiration and *** sequencing identified a mutation in the GATA1 *** receiving the diagnosis,the parents decided against medical care for their child,and the baby died at home on day 9 after *** The newborn infant was diagnosed with trisomy 21-related *** sequencing identified a mutation in the GATA1 *** parents abandoned medical treatment for their infant after receiving the diagnosis,and the infant died at home on the 9th day after birth.

关键词： Congenital leukemia Trisomy 21 GATA1 Acute myeloid leukemia Literature review Case report

Association between fetal macrosomia and risk of obesity in children under 3 years in Western China: a cohort study

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World Journal of Pediatrics 2019年第2期15卷 153-160页

作者： Xiong-Fei Pan Li Tang Andy H.Lee Colin Binns chun-xia yang Zhu-Ping Xu Jian-Li Zhang Yong yang Hong Wang Xin Sun Chinese Evidence-based Medicine Center Center for Clinical Epidemiology and Evidence-based MedicineWest China HospitalSichuan UniversityNo.37 Guoxue AlleyChengdu 610041SichuanChina Department of Epidemiology and Biostatistics School of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Department of Research and Education Sichuan Jinxin Women's and Children's HospitalChengduChina Department of Epidemiology and Biostatistics School of Public HealthCurtin UniversityPerthWAAustralia Department of Epidemiology and Biostatistics West China School of Public HealthSichuan UniversityChengduSichuanChina Shuangliu Maternal and Child Health Hospital ChengduSichuanChina Wenjiang Maternal and Child Health Hospital ChengduSichuanChina Longquan Maternal and Child Health Hospital ChengduSichuanChina Pidu Maternal and Child Health Hospital ChengduSichuanChina

Background Fetal macrosomia,defined as birth weight equal or over 4000 g,is a major concern for both neonatal and maternal health.A rapid increasing trend in fetal macrosomia is observed in different regions of *** aimed to examine the association between fetal macrosomia and risk of childhood obesity in Western *** All macrosomic live singletons (≥ 4000 g),and a random sample of singletons with normal birth weight (2500-3999 g) born in four districts of Chengdu,Western China,in 2011 were included in the cohort *** demographics,obstetric factors,labor and delivery summary at baseline were extracted from the Chengdu Maternal and Child Health Management *** measurements before 3 years and infant feeding information at around 6 months were also *** obesity under 3 years was primarily defined as a weight-for-length/height z score ≥ 1.645 using the WHO growth *** definitions were based on weight-for-age and body mass index (BMI)-for-age over the same *** A total of 1767 infants were included in the analyses,of whom 714 were *** controlling for maternal age,parity,gestational age and anemia at the first antenatal visit,pre-pregnancy BMI,gestational weight gain,gestational age at birth,baby age and sex,and breastfeeding practices at 6 months,the risk of childhood obesity defined according to weight-for-length/height among macrosomic babies was 1.90 (95% confidence interval 1.04-3.49) times that of babies with normal birth *** risk of childhood obesity for macrosomic babies was 3.74 (1.96-7.14) and 1.64 (0.89-3.00) times higher based on weight-for-age and BMI-for-age,*** Fetal macrosomia is associated with increased risk of obesity in children under 3 years in Western China.

关键词： Birth weight Child growth China Fetal macrosomia Obesity

Relationship between genetic polymorphisms of ALDH2 and ADH1B and esophageal cancer risk:A meta-analysis

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World Journal of Gastroenterology 2010年第33期16卷 4210-4220页

作者： Shu-Juan yang Akira Yokoyama Tetsuji Yokoyama Yu-Chuan Huang Si-Ying Wu Ying Shao Jin Niu Jie Wang Yu Liu xiao-Qiao Zhou chun-xia yang Departmentof Epidemiology West China School of Public HealthSichuan UniversityChengdu 610041Sichuan ProvinceChina Clinical Research Unit National HospitalOrganization Kurihama Alcoholism CenterYokosuka 239-0841Japan Department of Human Resources Development National Institute of Public HealthWako 351-0104Japan Technology Research and DevelopmentCenter China Tobacco Chuanyu IndustrialCorporationChengdu Department of Epidemiology and Health Statistics Fujian Medical Unive rsityFuzhou 350108Fujian ProvinceChina Department of Periodontology West China College of StomatologySichuan UniversityChengdu 610041Sichuan ProvinceChina West China School of Public Health Sichuan UniversityChengdu 610041Sichuan ProvinceChina 610066Sichuan ProvinceChina

AIM:To evaluate the contribution of alcohol dehydrogenase-1B(ADH1B)and aldehyde dehydrogenase-2 (ALDH2)polymorphisms to the risk of esophageal ***:Nineteen articles were included by searching MEDLINE,EMBASE and the Chinese Biomedical Database,13 on ADH1B and 18 on *** performed a meta-analysis of case-control studies including 13 studies on ADH1B(cases/controls:2390/7100)and 18 studies on ALDH2(2631/6030).RESULTS:The crude odds ratio[OR(95%confidence interval)]was 2.91(2.04-4.14)for ADH1B*1/*1(vs ADH1B*2/*2)and 1.32(1.17-1.49)for ADH1B*1/**** crude OR for ALDH2*1/*2(vs ALDH2*1/*1)was 2.52(1.76-3.61).ADH1B*1/*1 increased the risk of esophageal cancer among never/rare[1.56(0.93-2.61)],moderate[2.71(1.37-5.35)],and heavy drinkers[3.22 (2.27-4.57)].ADH1B*1/*2 was associated with a modest risk among moderate drinkers[1.43(1.09-1.87)].ALDH2*1/*2 increased the risk among never/rare[1.28 (0.91-1.80)],moderate[3.12(1.95-5.01)],and heavy [7.12(4.67-10.86)]drinkers,and among ex-drinkers [5.64(1.57-20.25)].ALDH2*2/*2 increased the risk among drinkers[4.42(1.72-11.36)].ADH1B*1/*1 plus ALDH2*1/*2 was associated with the highest risk for heavy drinkers[12.45(2.9-53.46)].The results of the meta-regression analysis showed that the effects of ADH1B*1/*1 and ALDH2*1/*2 increased with the level of alcohol ***2*1/*2 was associated with a high risk among Taiwan Chinese and Japanese drinkers,as opposed to a moderate risk among drinkers in high-incidence regions of China's ***1B*1/*1 in heavy drinkers and ALDH2*1/*2 in moderate-toheavy drinkers was associated with similarly high risk among both men and ***:ADH1B/ALDH2 genotypes affect the risk of esophageal cancer,and the risk is modified by alcohol consumption,ethnicity,and gender.

关键词： Alcohol dehydrogenase-1B Aldehyde dehy- drogenase-2 Esophageal cancer Meta-analysis