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Review of Large Spacecraft Deployable Membrane Antenna Structures

Chinese Journal of Mechanical Engineering 2017年第6期30卷 1447-1459页

作者： Zhi-Quan liu Hui Qiu Xiao li shu-li yang Beijing Institute of Spacecraft System Engineering China Academy of Space Technology Beijing 100094 China

The demand for large antennas in future space missions has increasingly stimulated the development of deployable membrane antenna structures owing to their light weight and small stowage volume. However, there is little literature providing a comprehensive review and comparison of different membrane antenna structures. Space-borne membrane antenna structures are mainly classified as either parabolic or planar membrane antenna structures. For parabolic membrane antenna structures, there are five deploying and forming methods, including inflation, inflation-rigidization, elastic ribs driven, Shape Memory Polymer （SMP）-inflation, and electrostatic form- ing. The development and detailed comparison of these five methods are presented. Then, properties of membrane materials （including polyester film and polyimide film） for parabolic membrane antennas are compared. Additionally, for planar membrane antenna structures, frame shapes have changed from circular to rectangular, and different ten- sioning systems have emerged successively, including single Miura-Natori, double, and multi-layer tensioning systems. Recent advances in structural configurations, tensioning system design, and dynamic analysis for planar membrane antenna structures are investigated. Finally, future trends for large space membrane antenna structures are pointed out and technical problems are proposed, including design and analysis of membrane structures,materials and processes, membrane packing, surface accuracy stability, and test and verification technology. Through a review of large deployable membrane antenna structures, guidance for space membrane-antenna research and applications is provided.

关键词： Membrane antenna. Parabolic Plane.Tensioning system Dynamics

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分级大/介孔氮化碳-二氧化钛复合材料对U(Ⅵ)的光催化还原

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核化学与放射化学 2024年第4期46卷 396-400,I0004页

作者：李姝阳牛智伟崔振鹏潘多强吴王锁国民核生化灾害防护国家重点实验室北京102205 西南科技大学核废物与环境安全省部共建协同创新中心四川绵阳621010 兰州大学教育部稀有同位素前沿科学中心甘肃兰州730000

光催化技术可以利用光生电子将易溶解的U(Ⅵ)还原为难溶解的U(Ⅳ)。本工作在不引入有机模板或辅助添加剂的情况下,合成了分级大/介孔g-C_(3)N_(4)-TiO_(2)复合材料,并用于光催化还原U(Ⅵ)。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)... 详细信息

光催化技术可以利用光生电子将易溶解的U(Ⅵ)还原为难溶解的U(Ⅳ)。本工作在不引入有机模板或辅助添加剂的情况下,合成了分级大/介孔g-C_(3)N_(4)-TiO_(2)复合材料,并用于光催化还原U(Ⅵ)。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、全自动比表面积物理吸附仪(BET)、紫外-可见漫反射光谱仪(UV-vis DRS)等先进表征设备对g-C_(3)N_(4)-TiO_(2)复合材料的形貌结构和光学性质进行了研究。通过光催化实验对g-C_(3)N_(4)-TiO_(2)复合材料光催化还原U(Ⅵ)的性能进行了研究。结果表明:g-C_(3)N_(4)-TiO_(2)复合材料兼具分级大/介孔TiO_(2)和g-C_(3)N_(4)的优点,不仅具有大的比表面积(174.68 m^(2)/g)和长通道,而且具有更广的光吸收范围。因此,g-C_(3)N_(4)-TiO_(2)复合材料在15 min内对U(Ⅵ)的去除率就高达98.4%。本工作对光催化处理含铀放射性废水提供了新的思路。

关键词： TiO_(2) g-C_(3)N_(4) 光催化铀分级介孔

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氮化碳异质结用于光催化还原U(Ⅵ)的研究进展

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核化学与放射化学 2024年第4期46卷 299-313,I0001页

作者：吴林珍张玲孟旗李姝阳张友魁段涛西南科技大学核废物与环境安全省部共建协同创新中心环境友好能源材料国家重点实验室四川绵阳621010 西南科技大学四川天府新区创新研究院四川成都610299

对核工业产生的含铀废水进行铀污染处理和铀资源回收,有利于维护核能的可持续发展。光催化还原技术友好地协同了吸附-还原能力,克服了单一吸附去除的热力学限制,用于核废水中铀去除与回收具有较大的发展潜力。氮化碳基纳米材料因其优异... 详细信息

对核工业产生的含铀废水进行铀污染处理和铀资源回收,有利于维护核能的可持续发展。光催化还原技术友好地协同了吸附-还原能力,克服了单一吸附去除的热力学限制,用于核废水中铀去除与回收具有较大的发展潜力。氮化碳基纳米材料因其优异的光化学性能、出色的理化可调性和良好的化学稳定性而被认为是一类光催化U(Ⅵ)还原的理想光催化剂。近年来围绕氮化碳进行的改性和应用研究为光催化铀还原提供了深入见解。近期的研究揭示了基于C_(3)N_(4)的异质结纳米结构的构筑及其对铀的光催化还原过程和机制。本文旨在阐明这一快速发展的主题,立足于光催化还原U(Ⅵ)的机理,着眼于有效改善C_(3)N_(4)的光催化性能,系统总结了基于C_(3)N_(4)异质结光催化材料的设计开发及其在U(Ⅵ)还原中的应用。最后,展望了当前基于C_(3)N_(4)的光催化材料在含铀废水中对U(Ⅵ)的还原去除面临的困难,为未来的突破提供视角和方向。

关键词：氮化碳异质结光催化铀还原核废水

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马克思实践哲学视域下教育家精神的内在意蕴和践行路径

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西安建筑科技大学学报（社会科学版） 2024年第3期43卷 33-39页

作者：文涛杜忠泽李舒扬西安建筑科技大学高教研究所陕西西安710055

习近平总书记提出的教育家精神,完整阐述了中国特有的教育家精神的核心要义和实践要求,建构了新时代教师应该具备的集体人格和精神风貌,是对教师职业素养、精神和能力的凝练与升华。立足马克思实践哲学视域,认为教育的过程,是马克思实... 详细信息

习近平总书记提出的教育家精神,完整阐述了中国特有的教育家精神的核心要义和实践要求,建构了新时代教师应该具备的集体人格和精神风貌,是对教师职业素养、精神和能力的凝练与升华。立足马克思实践哲学视域,认为教育的过程,是马克思实践哲学“实践、认识、再实践、再认识的循环往复”之生动体现和现实检验。对教育特质进行分析,提出教育过程是主观与客观、主体与客体统一,是实践与认识统一,是真理尺度与价值尺度统一的过程;在此基础上,探究了教育家精神的内在意蕴:教育家精神源起的客观实在性、教育家精神形成的主观能动性、教育家精神提出的社会历史性。进而从保持从业初心和情怀、从业水平和能力、从业品格和素养的认识与实践等三个层面提供了教育家精神的践行路径。

关键词：马克思实践哲学教育教育家精神践行路径

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Photosynthetic response dynamics in the invasive species Tithonia diversifolia and two co-occurring native shrub species under fluctuating light conditions

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Plant Diversity 2024年第2期46卷 265-273页

作者： Ju li shu-Bin Zhang yang-Ping li CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunMengla 666303YunnanChina University of Chinese Academy of Sciences Beijing 100049China

To determine the invasiveness of invasive plants,many studies have compared photosynthetic traits or strategies between invasive and native ***,few studies have compared the photosynthetic dynamics between invasive and native species during light *** compared photosynthetic induction,relaxation dynamics and leaf traits between the invasive species,Tithonia diversifolia and two native species,Clerodendrum bungei and Blumea balsamifera,in full-sun and shady *** photosynthetic dynamics and leaf traits differed among *** showed a slower induction speed and stomatal opening response but had higher average intrinsic water-use efficiency than the two native species in full-sun ***,the slow induction response may be attributed to the longer stomatal length in *** had a significant effect on photosynthetic dynamics in *** and *** but not in *** shady habitat,*** had a faster photosynthetic induction response than in full-sun habitat,leading to a higher average stomatal conductance during photosynthetic induction in *** than in the two native *** contrast,*** had a larger stomatal length and slower photosynthetic induction and relaxation response in shady habitat than in full-sun habitat,resulting in higher carbon gain during photosynthetic ***,in both habitats,*** had an overall higher carbon gain during light fluctuations than the two native *** results indicated that *** can adopt more effective response strategies under fluctuating light environments to maximize carbon gain,which may contribute to its successful invasion.

关键词： Invasive plant Photosynthetic induction Photosynthetic relaxation Carbon gain Stomatal traits Tithonia diversifolia

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Deficiency of Trp53 and Rb1 in myeloid cell lineage spontaneously develops acute myeloid leukemia in a mouse model

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Genes & Diseases 2024年第1期11卷 4-6页

作者： yang li shu-ting yang shuying yang Department of Basic&Translational Sciences School of Dental MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA Department of Orthopaedic Surgery School of MedicineJohns Hopkins University BaltimoreMD 21205USA Center for Innovation&Precision Dentistry School of Dental MedicineSchool of Engineering and Applied SciencesUniversity of PennsylvaniaPhiladelphiaPA 19104USA The Penn Center for Musculoskeletal Disorders School of MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA

Acute myeloid leukemia(AML)is a rapidly lethal blood cancer characterized by aberrant proliferation and differentiation of myeloid progenitors in the hematopoietic *** recent decades,AML patients are significantly *** 2019 alone,21,450 new AML cases were diagnosed in the United States,with an estimated 10,920 deaths due to ***’s worse,AML occurs with an increasing incidence with advanced age,and the survival rate remains dismal with a median overall survival of only 5e10 *** great advances in allogenic transplant and chemotherapy,the therapeutic outcomes are unfavorable due to the disease relapse and mortality *** importantly,the development of more specific and effective therapies was hampered in part by the lack of proper animal models for ***,management and elucidation of the pathological mechanism of AML remain an ongoing challenge,and the development of effective AML mouse models and treatment options are urgently needed.

关键词： myeloid Acute leukemia

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Evolution of inclusions in vacuum induction melting of superalloys containing 70%return material

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Journal of Iron and Steel Research International 2024年第3期31卷 719-728页

作者： Jin-guo Gao shu-lei yang shu-feng yang Jing-she li Wei liu Meng-jing Zhao An-ren Wang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Metallurgical and Building Materials Business Department China International Engineering Consulting CorporationBeijing 100048China

The variation law of inclusions type and size in the vacuum induction melting process and ingot of Ni-based superalloy containing 70%return material was studied by industrial test sampling,and the mechanism of inclusions formation was analyzed with thermodynamic *** results show that there are mainly two types of composite inclusions in the vacuum induction melting of Ni-based superalloys,which are nitride-and oxide-based composite inclusions,like Al_(2)O_(3)-SiO_(2)-Cr_(2)O_(3),TiN-(Mo,Nb)C,*** type and proportion of inclusions from the center to the edge of the vacuum induction ingot did not change *** number density of inclusions from the center to the edge of the ingot varied less,and the size of inclusions became smaller from the center to the *** addition,thermodynamic calculations show that oxides(M_(2)O_(3))are present in the liquid phase and mainly contain Al,Ti,Cr,Fe and O *** nitride consists mainly of Ti and N and contains small amounts of Cr,C,Nb,and Mo *** is consistent with the results of industrial *** the temperature decreases,the precipitation phases such as M_(2)O_(3),MN,γ,MC,δ,γ'andμphases are gradually precipitated,where oxides and nitrides are present in the liquid *** contents of O and N elements are the main influencing factors for the inclusions content and precipitation temperature;when the nitrogen content is reduced to below 0.0015%,it can make MN precipitate below the liquid-phase line.

关键词： Ni-based superalloy Vacuum induction melting Return material Inclusion Thermodynamic

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Congenital dysfibrinogenemia misdiagnosed and inappropriately treated as acute fatty liver in pregnancy:A case report and review of literature

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World Journal of Clinical Cases 2022年第35期10卷 12996-13005页

作者： Yan Jia Xi-Wen Zhang Yi-Shi Wu Qing-Yu Wang shu-li yang Department of Obstetrics and Gynecology The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Orthopedic Medical Center The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina

BACKGROUND The purpose of this study was to report the rare case of a pregnant woman with congenital dysfibrinogenemia(CD)misdiagnosed as acute fatty *** was treated according to the principles of acute fatty liver but achieved good clinical *** SUMMARY A 30-year-old woman presented with 39(6/7)wk of menopause and 6 h of irregular abdominal pain and attended our *** surgery was performed due to fetal *** management followed the treatment principle of acute fatty *** sequencing was carried out on the pregnant woman and her *** values of the patient on admission were prothrombin time 33.7 s,activated partial thromboplastin time 60.4 s,thrombin time 45.2 s,and fibrinogen 0.60 g/*** sequencing results showed that the woman carried a pathogenic heterozygous variation of the fibrinogen alpha chain gene(FGA),which is closely related to hereditary fibrinogen abnormality,and the mutation site was located in *** a follow-up period of 12 mo,the mother and her newborn had a good prognosis without bleeding or *** Pregnant women with CD may have atypical symptoms,which can easily lead to *** addition,treatment can be attempted according to the principles of acute fatty liver *** rare pregnant patient with CD was caused by a novel FGA(p.R350H)gene mutation.

关键词： Gene mutation Fibrinogen Congenital dysfibrinogenemia Pregnancy Case report

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Flow stress equation for multipass hot-rolling of aluminum alloys

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Journal of Central South University of Technology 2001年第1期8卷 13-17页

作者： ZHANG Hui,PENG Da shu,yang li bin,MENG li ping (Department of Materials Science and Engineering, Central South University, Changsha 410083, China) 1. Department of Materials Science and Engineering Central South University 410083 Changsha China

A series of simple axisymmetric compression tests were carried out on the computer servo controlled Gleeble 1 500 machine when strain rates ranged between 0.05 25 s -1 and deformation temperature 300 500 ℃. The results show that flow stress is related to the Zener Hollonom parameter Z and strain, as well as the static recrystallization fraction between passes during multipass hot deformation of 5182 aluminum alloy. Hence, a modified exponential flow stress equation was presented by considering the values of ln A and β as functions of strain, and by using the uniform softening method and incorporating the static recrystallization fraction between passes to consider the effects of residual strain during multipass hot rolling of 5182 aluminum alloy. The validity of the equation was examined by a typical non isothermal multipass deformation test.

关键词： aluminum alloy multipass hot rolling flow stress equation

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A 30-year overview of sodium-ion batteries

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Carbon Energy 2024年第6期6卷 56-98页

作者： Yun Gao Hang Zhang Jian Peng lin li Yao Xiao li li yang liu Yun Qiao shu-Lei Chou School of Environmental and Chemical Engineering Shanghai UniversityShanghaiChina College of Chemistry and Materials Engineering Wenzhou UniversityWenzhouZhejiangChina Institute for Superconducting and Electronic Materials University of WollongongWollongongNew South WalesAustralia

Sodium-ion batteries(NIBs)have emerged as a promising alternative to commercial lithium-ion batteries(liBs)due to the similar properties of the li and Na elements as well as the abundance and accessibility of Na *** of the current research has been focused on the half-cell system(using Na metal as the counter electrode)to evaluate the performance of the cathode/anode/*** relationship between the performance achieved in half cells and that obtained in full cells,however,has been neglected in much of this ***,the trade-off in the relationship between electrochemical performance and cost needs to be given more ***,systematic and comprehensive insights into the research status and key issues for the full-cell system need to be gained to advance its ***,this review evaluates the recent progress based on various cathodes and highlights the most significant challenges for full *** strategies have also been proposed to enhance the electrochemical performance of NIBs,including designing electrode materials,optimizing electrolytes,sodium compensation,and so ***,perspectives and outlooks are provided to guide future research on sodium-ion full cells.

关键词： commercial application electrode electrolyte sodium-ion full cell strategies

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