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Thermal analysis of the baffle structure of the Solar Space Telescope

Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1755-1764页

作者： li rong1,2.3.& wang sen1,{2.,chinese academy of sciences,Beijing 100012.china 2.Graduate University of chinese academy of sciences,Beijing 100049,china 3 Key Laboratory of Solar Activity,national astronomical observatories of chinese academy of sciences,Beijing 100012.china 1. national astronomical {2. Chinese Academy of Sciences Beijing 100012 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Key Laboratory of Solar Activity National Astronomical Observatories of Chinese Academy of Sciences Beijing 100012 China

The SST(Space Solar Telescope) is an astronomical telescope with a primary mirror of 1 m in *** observes the sun with a small view field to ensure that its high spatial resolution imaging has 0.1″-0.15″ and high SNR(signal to noise ratio).Surrounding the small view field is still the sun,which is an intense source of both heat and stray *** baffles(the main baffle,the aperture,and the outer baffle),which are used to eliminate the stray light,will change the thermal flux in the SST and will weaken the effect of the thermal control *** this study,the compatibility analysis of the thermal effect of baffle structures in SST is *** GCF(Geometry Composing Function) and BRDF(Bidirectional Reflectance Distribution Function),which are two inherent related parameters in the compatibility analysis,are *** objective and method of the compatibility analysis are *** the thermal analysis software,the temperature fields are calculated for different lengths of the main baffle,different radii of apertures,different lengths of the outer baffle with a 3' tilt angle and 16' tilt angle,and different tilt angles of the outer baffle with a 2.0 mm length.A series of configurations and sizes of the baffles are studied with the goals of both thermal control and elimination of stray *** design of the baffle structure of SST is achieved:the main baffle of length 4100 mm,the internal shield of radius 494 mm,the outer baffle of length 2.0 mm,and the outer baffle of tilt angle 3' are successfully *** paper presents the relationship between the thermal control design and stray light elimination plan in the *** aims of the optimal design of the baffle structure of SST are *** thoughts and methods of the optimal analysis are also useful for similar optical telescopes designed for solar observation.

关键词： baffle the main baffle the outer baffle GCF BRDF

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Regulation mechanism of EM parameters in natural ferrite and its application in microwave absorbing materials

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Science china(Technological sciences) 2006年第1期49卷 38-49页

作者： ZHENG Yongchun1,2. wang Shijie2. FENG Junming2. li Chunlai1, OUYANG Ziyuan1,2. liU Jianzhong1 & li Xiaobiao2.1. national astronomical observatories, chinese academy of sciences, Beijing 100012, china 2. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, chinese academy of sciences, Guiyang 550002. china 1. national astronomical {2. Chinese Academy of Sciences Beijing 100012 China 2. State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Electromagnetic (EM) parameters (ε ′, ε ″, μ ′, μ″ ) of several M2.Fe2.4 and Fe2.3 type natural ferrites with different geological occurrences are measured in this pa-per. The measurement results show that EM parameters of a magmatic-occurring natural ferrite is very different from other types occurring from sedimentary-metamorphic iron deposit, hydrothermal vein iron deposit, outer contact of magmatic iron deposit. It has potential to be used as magnetic absorbent in microwave absorbing materials. After min-eral separation and concentration, this magmatic-occurring natural ferrite was processed into type A ferrite absorbent. Type A natural ferrite absorbent is a kind of magnetic material with low dielectric constants, high magnetic conductivity and high EM loss. Its EM pa-rameters are ε ′ = 58.60, ε ″ = 10.0, μ ′ = 1.2.1.5, μ ″ = 1.0-1.2. respectively. In order to illuminate the regulation mechanism of EM parameters, we studied the chemical and mineral composition of type A ferrite absorbent. There is high concentration of natural impurities, which regulate the EM parameters of type A ferrite greatly. For comparison, the other types of natural ferrite, single-phase magnetite and two-phase iron minerals (ilmen-ite and magnetite), have few impurity. Thus regulation mechanism of EM parameters was absent in these ferrites. As a result, the regulation of EM parameters is advantageous to develop type A natural ferrite as excellent absorbent, lowers the reflectivity coefficients and enhances the absorbing efficiency of MAM made from it. Furthermore, the impurities in type A natural ferrite and its effects on EM parameters are very difficult to simulate in the synthesize ferrite. The carbonyl-iron powder is another kind of absorbent that is used ex-tensively in MAM. To compare the absorbing properties of these two absorbent, type A natural ferrite and carbonyl-iron powder were mixed with rubber and processed into mi-crowave absorbing sheets with the same procedures and tec

关键词： natural impure ferrite, complex permittivity, complex permeability, microwave absorbing materials.

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Polyzwitterionic cross-linked double network hydrogel electrolyte enabling high-stable Zn anode

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Nano Research 2024年第6期17卷 5278-5287页

作者： Mengyu Shi Junlong Zhang Guochuan Tang Ben wang sen wang Xiaoxian Ren Guojie li Weihua Chen Chuntai liu Changyu Shen State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou 450002China College of Chemistry and Green Catalysis Center Zhengzhou UniversityZhengzhou 450001China Research Institute of Interdisciplinary Science and School of Materials Science and Engineering Dongguan University of TechnologyDongguan 523808China

Zn metal anode suffers from dendrite issues and passive byproducts,which severely plagues the practical application of aqueous Zn metal ***,a polyzwitterionic cross-linked double network hydrogel electrolyte composed of physical crosslinking(hyaluronic acid)and chemical crosslinking(synthetic zwitterionic monomer copolymerized with acrylamide)is introduced to overcome these *** the one hand,highly hydrophilic physical network provides an energy dissipation channel to buffer stress and builds a H_(2.O-poor interface to avoid side *** the other hand,the charged groups(sulfonic and imidazolyl)in chemical crosslinking structure build anion/cation transport channels to boost ions’kinetics migration and regulate the typical solvent structure[Zn(H_(2.O)_(6)]^(2.)to R-SO_(3)^(−)[Zn(H_(2.O)_(4)]^(2.),with uniform electric field distribution and significant resistance to dendrites and parasitic *** on the above functions,the symmetric zinc cell exhibits superior cycle stability for more than 42. h at a high current density of 5 mA·cm^(−2.,and Zn||MnO_(2.full cell has a reversible specific capacity of 150 mAh·g^(−1)after 1000 cycles at 2.C with this hydrogel ***,the pouch cell delivers impressive flexibility and cyclability for energy-storage applications.

关键词： Zn anode dendrites parasitic reactions polyzwitterion double network hydrogel electrolyte

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Asperochones A and B,two antimicrobial aromatic polyketides from the endophytic fungus Aspergillus ***-2

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chinese Chemical Letters 2024年第9期35卷 206-209页

作者： Hong Zhang Cui-Ping li li-li wang Zhuo-Da Zhou Wen-sen li ling-Yi Kong Ming-Hua Yang Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China

Two novel fungal metabolites,asperochones A and B,were obtained from an Aspergillus *** structures were determined by 1D/2. nuclear magnetic resonance(NMR)spectroscopy,high resolution electrospray ionization mass spectroscopy(HRESIMS),and single-crystal X-ray diffraction *** A possesses an intriguing skeleton bearing 5/6/6/6/7/5/5/5 octacyclic ring system,and asperochone B also exhibits an unusual carbon skeleton with five stereochiral *** structures were proposed as heterotrimeric and heterodimeric products of aromatic *** addition,asperochone A exhibited a potential anti-tuberculosis effect since it showed a moderate potency against Mycobacterium smegmatis.

关键词： Aspergillus sp. Asperochones A and B Aromatic polyketides Heterotrimeric compound Anti-tuberculosis effect Antifibrotic activity

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Dynamic gut microbiome-metabolome in cationic bovine serum albumin induced experimental immune-complex glomerulonephritis and effect of losartan and mycophenolate mofetil on microbiota modulation

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Journal of Pharmaceutical Analysis 2024年第4期14卷 562-577页

作者： Wenying Shi Zhaojun li Weida wang Xikun liu Haijie Wu Xiaoguang Chen Xunrong Zhou sen Zhang State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing100050China State Key Laboratory of Functions and Applications of Medicinal Plants College of PharmacyGuizhou Provincial Engineering Technology Research Center for Chemical Drug R&DGuizhou Medical UniversityGuiyang550004China Department of Medicine Solna Center for Molecular MedicineKarolinska University Hospital and Karolinska InstituteStockholm17176Sweden Department of Pharmacy The Second Affiliated Hospital of Guizhou University of Traditional Chinese MedicineGuiyang550001China

Dynamic changes in gut dysbiosis and metabolomic dysregulation are associated with immune-complex glomerulonephritis(ICGN).However,an in-depth study on this topic is currently ***,we report an ICGN model to address this *** was induced via the intravenous injection of cationized bovine serum albumin(c-BSA)into Sprague-Dawley(SD)rats for two weeks,after which mycophenolate mofetil(MMF)and losartan were administered *** and six weeks after ICGN establishment,fecal samples were collected and 16S ribosomal DNA(rDNA)sequencing and untargeted metabolomic were *** microbiota transplantation(FMT)was conducted to determine whether gut normali-zation caused by MMF and losartan contributed to their renal protective effects.A gradual decline in microbial diversity and richness was accompanied by a loss of renal *** 18 genera were found to have significantly different relative abundances between the early and later stages,and Marvinbryantia and Allobaculum were markedly upregulated in both *** metabolomics indicated that the tryptophan metabolism was enhanced in ICGN,characterized by the overproduction of indole and kynurenic acid,while the serotonin pathway was *** of losartan and MMF ameliorated microbial dysbiosis and reduced the accumulation of indoxyl conjugates in *** using feces from animals administered MMF and losartan improved gut dysbiosis by decreasing the Firmicutes/Bacteroidetes(F/B)ratio but did not improve renal *** findings indicate that ICGN induces serous gut dysbiosis,wherein an altered tryptophan metabolism may contribute to its *** and losartan significantly reversed the gut microbial and metabolomic dysbiosis,which partially contributed to their renoprotective effects.

关键词： Immune-complex glomerulonephritis Gut microbiome Metabolomics Fecal microbiota transplant Tryptophan metabolism

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In-situ electrochemical study on the eff ects of Fe(Ⅲ)on kinetics of pyrite acidic pressure oxidation

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Acta Geochimica 2024年第4期43卷 814-825页

作者： Yu Zhang Can Cui sen lin Heping li lian Yang Yadian Xie Hailiang Hu lingyun Zhou Huanjiang wang Chunyan li School of Chemical Engineering Guizhou Minzu UniversityGuiyang 550025China Key Laboratory of High-Temperature and High-Pressure Study of the Earth’s Interior Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

Fe(Ⅲ)has been proved to be a more eff ective oxidant than dissolved oxygen at ambient temperature,however,the role of Fe(Ⅲ)in pyrite acidic pressure oxidation was rarely discussed so *** this paper,in-situ electrochemical investigation was performed using a flow-through autoclave system in acidic pressure oxidation *** results illustrated that increasing Fe(Ⅲ)concentrations led to raising in redox potential of the solution,and decreased passivation of pyrite caused by deposition of elemental *** of Fe(Ⅲ)at pyrite surface was a fast reaction with low activation energy,it was only slightly promoted by rising ***,the oxidation rate of pyrite at all investigated Fe(Ⅲ)concentrations increased obviously with rising temperatures,the anodic reaction was the rate-limiting step in the overall *** energy of pyrite oxidation decreased from 47.74 to 2..79 kJ/mol when Fe(Ⅲ)concentration was increased from 0.05 to 0.50 g/L,showing that the reaction kinetics were limited by the rate of electrochemical reaction at low Fe(Ⅲ)concentrations,while,it gradually turned to be diffusion control with increasing Fe(Ⅲ)concentrations.

关键词： Pyrite Pressure oxidation Fe(Ⅲ) In-situ electrochemistry Hydrothermal experiment

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Three‐dimensional(3D)‐printed MXene high‐voltage aqueous micro‐supercapacitors with ultrahigh areal energy density and low‐temperature tolerance

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Carbon Energy 2024年第8期6卷 36-48页

作者： Yuanyuan Zhu Qingxiao Zhang Jiaxin Ma Pratteek Das liangzhu Zhang Hanqing liu {2. wang Hui li Zhong‐Shuai Wu State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianChina Key Laboratory of Spin Electron and Nanomaterials of Anhui Higher Education Institutes Suzhou UniversitySuzhouChina Shanghai Key Laboratory of Rare Earth Functional Materials and Education Ministry Key Laboratory of Resource Chemistry Shanghai Normal UniversityShanghaiChina University of chinese academy of sciences BeijingChina Dalian national Laboratory for Clean Energy Chinese Academy of SciencesDalianChina

The rapid advancement in the miniaturization,integration,and intelligence of electronic devices has escalated the demand for customizable microsupercapacitors(MSCs)with high energy ***,efficient microfabrication of safe and high‐energy MXene MSCs for integrating microelectronics remains a significant challenge due to the low voltage window in aqueous electrolytes(typically≤0.6 V)and limited areal mass loading of MXene ***,we tackle these challenges by developing a highconcentration(18mol kg^(−1))“water‐in‐liBr”(WiB)gel electrolyte for MXene symmetric MSCs(M‐SMSCs),demonstrating a record high voltage window of 1.8 ***,additive‐free aqueous MXene ink with excellent rheological behavior is developed for three‐dimensional(3D)printing customizable all‐MXene microelectrodes on various *** the synergy of a highvoltage WiB gel electrolyte and 3D‐printed microelectrodes,quasi‐solid‐state MSMSCs operating stably at 1.8 V are constructed,and achieve an ultrahigh areal energy density of 1772.Whcm^(−2.and excellent low‐temperature tolerance,with a long‐term operation at−40℃.Finally,by extending the 3D printing protocol,M‐SMSCs are integrated with humidity sensors on a single planar substrate,demonstrating their reliability in miniaturized integrated microsystems.

关键词： 3D printing aqueous electrolyte high voltage micro‐supercapacitors MXene

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A flame-retardant binder with high polysulfide affinity for safe and stable lithium–sulfur batteries

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Science china Chemistry 2024年第3期67卷 1028-1036页

作者： Guowei Yu Guofeng Ye Cheng wang Chenyang wang Zhaoyun wang Pu Hu Yu li Xi-Xi Feng Shuang-Jie Tan Min Yan sen Xin Zhitian liu Hubei Key Laboratory of Plasma Chemistry and Advanced Materials Hubei Engineering Technology Research Center of Optoelectronic and New Energy MaterialsSchool of Materials Science and EngineeringWuhan Institute of TechnologyWuhan 430205China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China University of chinese academy of sciences Beijing 100049China

lithium-sulfur(li-S) batteries have shown promises for the next-generation, high-energy electrochemical storage, yet are hindered by rapid performance decay due to the polysulfide shuttle in the cathode and safety concerns about potential thermal runaway. To address the above challenges, herein, we show a flame-retardant cathode binder that simultaneously improves the electrochemical stability and safety of batteries. The combination of soft and hard segments in the polymer framework of binders allows high flexibility and mechanical strength for adapting to the drastic volume change during the li(de)intercalation of the S cathode. The binder contains a large number of polar groups, which show the high affinity to polysulfides so that they help to anchor active S species at the cathode. These polar groups also help to regulate and facilitate the li-ion transport, promoting the kinetics of polysulfide conversion reaction. The binder contains abundant phosphine oxide groups, which, in the case of battery's thermal runaway, decompose and release PO· radicals to quench the combustion reactions and stop the fire. Consequently, li-S batteries using the new cathode binder show the improved electrochemical performance, including a low-capacity decay of 0.046% per cycle for 800 cycles at 1 C and favorable rate capabilities of up to 3 C. This work offers new insights on the practical realization of high-energy rechargeable batteries with stable storage electrochemistry and high safety.

关键词： lithium–sulfur battery polymer binder polysulfide affinity flame retardancy

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Oxygen tension modulates cell function in an in vitro three-dimensional glioblastoma tumor model

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Bio-Design and Manufacturing 2024年第3期7卷 307-319页

作者： sen wang Siqi Yao Na Pei Luge Bai Zhiyan Hao Dichen {2. Jiankang He J.Miguel O{2.veira Xiaoyan Xue {2.ng wang Xinggang Mao State Key Laboratory for Manufacturing System Engineering Xi’an Jiaotong UniversityXi’an 710054China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710054China NMPA Key Laboratory for Research and Evaluation of Additive Manufacturing Medical Devices Xi’an Jiaotong UniversityXi’an 710054China 3B’s Research Group I3Bs–Research Institute on BiomaterialsBiodegradables and BiomimeticsUniversity of MinhoHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal ICVS/3B’s-PT Government Associate Laboratory 4806-909 Braga/Guimar˜aesPortugal Department of Pharmacology School of PharmacyFourth Military Medical UniversityXi’an 710032China Department of Neurosurgery Xijing HospitalFourth Military Medical UniversityXi’an 710032China

Hypoxia is a typical feature of the tumor microenvironment,one of the most critical factors affecting cell behavior and tumor ***,the lack of tumor models able to precisely emulate natural brain tumor tissue has impeded the study of the effects of hypoxia on the progression and growth of tumor *** study reports a three-dimensional(3D)brain tumor model obtained by encapsulating U87MG(U87)cells in a hydrogel containing type I *** also documents the effect of various oxygen concentrations(1%,7%,and 2.%)in the culture environment on U87 cell morphology,proliferation,viability,cell cycle,apoptosis rate,and ***,it compares two-dimensional(2.)and 3D *** comparison purposes,cells cultured in flat culture dishes were used as the control(2. model).Cells cultured in the 3D model proliferated more slowly but had a higher apoptosis rate and proportion of cells in the resting phase(G0 phase)/gap I phase(G1 phase)than those cultured in the 2. ***,the two models yielded significantly different cell ***,hypoxia(e.g.,1%O2.affected cell morphology,slowed cell growth,reduced cell viability,and increased the apoptosis rate in the 3D *** results indicate that the constructed 3D model is effective for investigating the effects of biological and chemical factors on cell morphology and function,and can be more representative of the tumor microenvironment than 2. culture *** developed 3D glioblastoma tumor model is equally applicable to other studies in pharmacology and pathology.

关键词： Hypoxia Glioma Three-dimensional glioma model In vitro

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Study of the primordial lithium abundance

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 67-72页

作者： li ZhiHong1, li ErTao1, SU Jun1, li YunJu1, BAI XiXiang1, GUO Bing1, wang YouBao1, CHEN YongShou1, HOU SuQing1, ZENG Sheng1, liAN Gang1, SHI Jianrong2.& liU WeiPing1 1 china Institute of Atomic Energy, Beijing 102.13, china 2.9} astronomical observatories, {12., Beijing 100012, china china Inst Atom Energy Beijing 102413 Peoples R China chinese Acad Sci Natl Astron Observ Beijing 100012 Peoples R China

lithium isotopes have attracted an intense interest because the abundance of both 6li and 6li from big bang nucleosynthesis (BBN) is one of the puzzles in nuclear astrophysics. Many investigations of both astrophysical observation and nucleosynthesis calculation have been carried out to solve the puzzle, but it is not solved yet. Several nuclear reactions involving lithium have been indirectly measured at china Institute of Atomic Energy, Beijing. The Standard BBN (SBBN) network calculations are then performed to investigate the primordial lithium abundance. The result shows that these nuclear reactions have minimal effect on the SBBN abundances of 6li and 7li.

关键词： big bang nucleosynthesis element abundance nuclear reaction network

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