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Design method for hypersonic bump inlet based on transverse pressure gradient

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第6期23卷 479-494页

作者： Shang-cheng XU Yi WANG Zhen-guo WANG xiao-qiang fan Bing XIONG College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Transverse pressure gradient(TPG)is one of the key factors influencing the boundary layer airflow diversion in a bump inlet.This paper proposes a novel TPG-based hypersonic bump inlet design method.This method consists of two steps.First,a parametric optimization approach is employed to design a series of 2D inlets with various compression efficiencies.Then,according to the prescribed TPG,the optimized inlets are placed in different osculating planes to generate a 3D bump inlet.This method provides a means to directly control the aerodynamic parameters of the bump rather than the geometric parameters.By performing this method to a hypersonic chin inlet,a long and wide bump surface is formed in the compression wall,which leads to good integration of the bump/inlet.Results show that a part of the near-wall boundary layer flow is diverted by the bump,resulting in a slight decrease in the mass flow but a significant improvement in the total pressure recovery.In addition,the starting ability is significantly improved by adding the bump surface.Analysis reveals that the bump has a 3D rebuilding effect on the large-scale separation bubble of the unstarted inlet.Finally,a mass flow correction is performed on the designed bump inlet to increase the mass flow to full airflow capture.The results show that the mass flow rate of the corrected bump inlet reaches up to 0.9993,demonstrating that the correction method is effective.

关键词： Hypersonic bump inlet Transverse pressure gradient(TPG) Boundary layer flow Total pressure recovery Starting ability Mass flow correction

Development of a displacement-reactivity feedback model for dynamic behavior simulation in fast burst reactor

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Nuclear Science and Techniques 2019年第5期30卷 82-91页

作者： Jiang-Meng Wang Hui Gao Qi-Lin Xie xiao-qiang fan Da-Zhi Qian Key Laboratory of Neutron Physics China Academy of Engineering Physics Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics

In this study, a displacement-reactivity feedback model, which can directly represent the inherent ‘‘thermal expansion extinction effect'' of fast burst reactors(FBRs),was developed with the aid of the static neutron transport component of the FBR-MPC code. Dynamic behaviors of bursts in the Godiva I reactor were simulated by coupling the simplified multiphysics models consisting of the point kinetic equations for neutronics, adiabatic equation for temperature, and thermoelastic equations for displacement/stress with the developed model. The results were compared with the corresponding experimental data and those obtained using the traditional fission yield(temperature rise)-reactivity feedback models. It was found that the developed model can provide good results for the bursts with no or a small inertia effect. For the bursts with a prominent inertia effect, the smaller burst width and asymmetric distribution of the fission rate curve, noticed in the experiments but not evident using the traditional models, can be reproduced. In addition, the realistic oscillations in reactivity and fission rate caused by the core vibration, as well as the deeper sub-prompt criticality in the plateau following the burst, can be observed. Therefore, the developed displacement-reactivity feedback model can be expected to be an effective tool for calculating the dynamic behaviors of bursts.

关键词： Displacement-reactivity feedback model Prompt supercritical Coupled calculation Fast burst reactor

甲烷氧化偶联制乙烯Na–W–Mn/SiO_(2)催化剂的研究进展

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中国科学：化学 2024年第2期54卷 231-249页

作者：高欣宋佳欣范晓强于学华赵震沈阳师范大学化学化工学院能源与环境催化研究所沈阳110034 中国石油大学(北京)重质油国家重点实验室北京102249

乙烯产量是衡量一个国家石油化工行业水平的重要指标.因此,将甲烷高效转化为乙烯的甲烷氧化偶联(OCM)反应成为催化工业和能源领域的热门话题,甲烷氧化偶联工艺也已成为世界各国的研究热点.然而OCM反应是同时结合了多相反应和均相反应的... 详细信息

乙烯产量是衡量一个国家石油化工行业水平的重要指标.因此,将甲烷高效转化为乙烯的甲烷氧化偶联(OCM)反应成为催化工业和能源领域的热门话题,甲烷氧化偶联工艺也已成为世界各国的研究热点.然而OCM反应是同时结合了多相反应和均相反应的复杂反应网络,使得OCM反应高效催化剂的开发面临着重大挑战.其中, Na–W–Mn/SiO_(2)体系催化剂是目前综合性能最好的催化剂,但Na–W–Mn/SiO_(2)催化剂组分复杂,反应所需温度高,活性中心仍存在争议.因此本文主要总结讨论了该体系催化剂上OCM反应机理,以及氧物种和酸碱性对OCM反应的影响.并详细介绍了体系中各活性组分在反应中的作用,以及各种原位表征手段在OCM机理研究中的应用.最后对OCM反应在高温原位表征,低温可控OCM反应以及化学链循环反应方向进行了展望.

关键词：甲烷催化剂 OCM 反应机理 Na–W–Mn/SiO_(2)活性位

Effect of electrochemical etching current on prepared perforated silicon structures for neutron detectors

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Frontiers of Materials Science 2013年第1期7卷 96-101页

作者： xiao-qiang fan Yong JIANG Chang-Yong ZHAN Yu ZOU Jian-Chun WU Ning-Kang HUANG Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China Key Laboratory of Radiation Physics and Technology (Ministry of Education) Institute of Nuclear Science and Technology Sichuan University Chengdu 610064 China

Neutron detector based on perforated silicon structures backfilled with neutron converting materials could be operated at a low voltage and improves the detection efficiency of thermal neutron. It is found that the intrinsic detection efficiency of thermal neutron is affected by a lot of factors such as the geometry, size, and depth of the perforation and so on. In this study, the perforated silicon was prepared by electrochemical etching. Effect of etching current on geometry, size, and depth of the perforated silicon structures for neutron detectors was also reported.

关键词： neutron detector silicon electrochemical etching current

Research on the quasi-isentropic driving model of aluminized explosives in the detonation wave propagation direction

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Defence Technology（防务技术） 2024年第2期32卷 596-618页

作者： Hongfu Wang Yan Liu fan Bai Chao He Yingliang Xu qiang Zhou Chuan xiao Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Research and Development Academy of Machinery Equipment Beijing100089China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China

Taking CL-20(Hexanitrohexaazaisowurtzitane)-based aluminized explosives with high gurney energy as the research object, this research experimentally investigates the work capability of different aluminized explosive formulations when driving metal flyer plates in the denotation wave propagation direction.The research results showed that the formulations with 43 μm aluminum(Al) powder particles(The particle sizes of Al powder were in the range of 2~43 μm) exhibited the optimal performance in driving flyer plates along the denotation wave propagation direction. Compared to the formulations with Al powder 13 μm, the formulations with Al powder 2 μm delivered better performance in accelerating metal flyer plates in the early stage, which, however, turned to be poor in the later stage. The CL-20-based explosives containing 25% Al far under-performed those containing 15% Al. Based on the proposed quasi-isentropic hypothesis, relevant isentropy theories, and the functional relationship between detonation parameters and entropy as well as Al reaction degree, the characteristic lines of aluminized explosives in accelerating flyer plates were theoretically studied, a quasi-isentropic theoretical model for the aluminized explosive driving the flyer plate was built and the calculation methods for the variations of flyer plate velocity, Al reaction degree, and detonation product parameters with time and axial positions were developed. The theoretical model built is verified by the experimental results of the CL-20-based aluminized explosive driving flyer plate. It was found that the model built could accurately calculate the variations of flyer plate velocity and Al reaction degree over time. In addition, how physical parameters including detonation product pressure and temperature varied with time and axial positions was identified. The action time of the positive pressure after the detonation of aluminized explosives was found prolonged and the downtrend of the temperature was slowed down and even reversed to a slight rise

关键词： Aluminized explosive Flyer plate experiment Quasi-isentropic theoretical model Al reaction Driving characteristics

Current understanding of ELF4 deficiency:a novel inborn error of immunity

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World Journal of Pediatrics 2024年第5期20卷 444-450页

作者： Hong-qiang Du xiao-Dong Zhao Department of Rheumatology&Immunology National Clinical Research Center for Child Health and DisordersMinistry of Education Key Laboratory of Child Development and DisordersChongqing Key Laboratory of Child Rare Diseases in Infection and ImmunityChildren’s Hospital of Chongqing Medical UniversityZhongshan Er Road 136Yuzhong DistrictChongqingChina

Background ELF4 deficiency has been recently recognized as a novel disorder within the spectrum of inborn errors of immunity(IEIs),specifically categorized as a“disease of immune dysregulation.”Cases of this condition,reported by our team and others,are very limited worldwide.As such,our current knowledge of this new disease remains preliminary.This review aims to provide a brief overview of the clinical manifestations,pathogenesis,and treatment strategies for this novel IEI.Data sources A comprehensive review was conducted after an extensive literature search in the PubMed/Medline database and websites concerning transcriptional factor ELF4 and reports concerning patients with ELF4 deficiency.Our search strategy was“ELF4 OR ETS-related transcription factor Elf-4 OR EL4-like factor 4 OR myeloid Elf-1-like factor”as of the time of manuscript submission.Results The current signature manifestations of ELF4 deficiency disorder are recurrent and prolonged oral ulcer,abdominal pain,and diarrhea in pediatric males.In some cases,immunodeficiency and autoimmunity can also be prominent.Targeted Sanger sequencing or whole exome sequencing can be used to detect variation in ELF4 gene.Western blotting for ELF4 expression of the patient’s cells can confirm the pathogenic effect of the variant.To fully confirm the pathogenicity of the variant,further functional test is strongly advised.Glucocorticoid and biologics are the mainstream management of ELF4 deficiency disorder.Conclusions Pediatric males presenting with recurring ulcerations in digestive tract epithelium with or without recurrent fever should be suspected of DEX.When atypical presentations are prominent,variations in ELF4 gene should be carefully evaluated functionally due to the complex nature of ELF4 function.Experience of treating DEX includes use of glucocorticoid and biologics and more precise treatment needs more patients to identify and further mechanistic study.

关键词： ELF4 transcription factor Immune dysregulation Inborn errors of immunity Mechanism Recurrent infections

Severe liver injury and clinical characteristics of occupational exposure to 2-amino-5-chloro-N,3-dimethylbenzamide: A case series

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 186-194页

作者： Meng-xiao Feng Hua Zou Yuan-qiang Lu Department of Emergency Medicine The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Key Laboratory for Diagnosis and Treatment of Aging and Physic-chemical Injury Diseases of Zhejiang Province Hangzhou 310003China Occupational Health and Radiation Protection Institute Zhejiang Provincial Center for Disease Control and PreventionHangzhou 310051China

Background:The 2-amino-5-chloro-N,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and pharmaceuticals.However,no literature currently exists on 2-amino-5-chloro-N,3-dimethylbenzamide poisoning in humans.This study aimed to reveal the health hazard of this chemical for humans and summarize the clinical characteristics of patients with occupational 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.Methods:This observational study included four patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning from June 2022 to July 2022.The entire course of the incidents was described in detail.Blood 2-amino-5-chloro-N,3-dimethylbenzamide concentrations were detected by a mass spectrometer.Hema-toxylin and eosin staining was performed to assess liver injury,and immunofluorescence was used to evaluate hepatic mitophagy.Results:The 2-amino-5-chloro-N,3-dimethylbenzamide powder(99%purity)entered the human body mainly via the skin and respiratory tract due to poor personal protective measures.The typical course of 2-amino-5-chloro-N,3-dimethylbenzamide poisoning was divided into latency,rash,fever,organic dam-age,and recovery phases in accordance with the clinical evolution.Rash and fever may be the important premonitory symptoms for further organ injuries.The chemical was detected in the blood of all patients and caused multiple organ injuries,predominantly liver injury,including kidney,myocardium,and micro-circulation.Three patients recovered smoothly after comprehensive treatments,including artificial liver therapy,continuous renal replacement therapy,glucocorticoids,and other symptomatic and supportive treatments.One patient survived by liver transplantation.The postoperative pathological findings of the removed liver showed acute liver failure,and immunofluorescence staining confirmed the abundance of mitophagy in residual hepatocytes.Conclusions:This study is the first to elaborate the clinical characteristics of patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.The chemical enter

关键词： 2-amino-5-chloro-N,3-dimethylbenzamide Poisoning Clinical characteristics Liver injury

Influence of oxygen-rich hot air composite gas medium on sintering performance and function mechanism

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1071-1081页

作者： Min Gan Hao-xiang Zheng xiao-hui fan Zhi-yun Ji qiang Li Ming Wu Yi-fan Wang xiao-long Wang Yu-feng Wu Xu-ling Chen Zeng-qing Sun xiao-xian Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina Shanxi Taigang Stainless Steel Co. Ltd.Taiyuan030003ShanxiChina

Hot air sintering technology is used to improve the quality and production efficiency of sintered ore.However,the current thick layer condition highlights the disadvantage of the low oxygen potential of the hot air sintering layer.Therefore,it is considered to use oxygen enrichment sintering to improve the environment of hot air sintering.Traditional sintering,hot air sintering,and oxygen-rich hot air sintering were compared through sintering cup experiments,and the influence of hot air and oxygen-rich hot air on sintering indexes was clarified.Hot air reduced the vertical sintering velocity,while improved the yield and tumbler index.Oxygen-rich hot air sintering contributed to improving the vertical sintering velocity while ensuring the quality of sintered ore,thus comprehensively improving production efficiency.Under the action of hot air,the highest temperature of the sintering layer increased and the high-temperature holding time was prolonged.After oxygen enrichment,the combustion efficiency of fuels in the upper layer of materials was promoted,which optimized heat distribution in the middle and lower layers of materials and increased the content of calcium ferrite in the sintered ore,thus strengthening the sintering process.

关键词： Iron ore sintering Hot air sintering Oxygen enrichment Function mechanism

Origin of the Yueguang gold deposit in Xinhua, Hunan Province, South China: insights from fl uid inclusion and hydrogen–oxygen stable isotope analysis

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Acta Geochimica 2024年第2期43卷 235-254页

作者： Hongxin fan qiang Wang Yulong Yang Yao Tang Hao Zou College of Earth Sciences Chengdu University of TechnologyChengdu 610059China College of Earth Sciences Jilin UniversityJilin 130061China

The Yueguang gold deposit is located in Fengjia,Xinhua County,Hunan Province,South China.It represents a recently discovered small-scale gold deposit situated in the southwestern region of the Jiangnan Orogenic Belt,west of the Baimashan granitic batholith.In order to discern the characteristics of the ore-formingﬂuids,the underlying mineralization processes,and establish a foundation for the origin of the Yueguang gold depositﬂuid inclusion micro-thermometry,as well as quartz hydrogen and oxygen isotope analysis,have been carried out on samples obtained from various stages of mineralization.The hydrothermal miner-alization stages within the Yueguang gold deposit can be categorized into three stages:(i)the barren,pre-ore quartz-pyrite stage(Stage Ⅰ),the quartz-pyrite-gold stage(Stage Ⅱ),and the post-ore quartz-carbonate stage(Stage Ⅲ),with the second stage being the main mineralization stage.Theﬂuid inclusions identiﬁed in samples from the main min-eralization stage can predominantly be described with the NaCl–H_(2)O and CO_(2)–NaCl–H_(2)O systems.These inclusions display homogenization temperatures ranging from 158.8 to 334.9℃,and theﬂuid salinity ranges from 0.3%to 4.0%(wt.%NaCl equiv.).Laser Raman spectroscopy analysis of individual inclusions further reveals the presence of gas-phases such as CO_(2),CH_(4),and N_(2).Isotopic analysis indicatesδ^(18)Oﬂuid values ranging from 3.95 to 6.7‰ and δDH_(2)O values ranging from-71.9 to-55.7‰.These results indi-cate that the ore-formingﬂuid of the Yueguang gold deposit belongs to metamorphic hydrothermalﬂuids of middle-low temperature and low salinity.In the process of ore formation,gold is transported in the form of Au(HS)2-complexes,with gold deposition being driven byﬂuid immiscibility.Therefore,the Yueguang gold deposit is categorized as an orogenic gold deposit dominated by metamorphic hydrother-malﬂuid.It may become a new target for gold exploration in the Baimashan region,central Hunan Province.

关键词： Hunan province Yueguang gold deposit Fluid inclusions Hydrogen–oxygen isotopes Laser Raman Fluid immiscibility Orogenic gold deposit