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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 {12. 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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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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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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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 2.10} astronomical {12., chinese Academy of sciences, 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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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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Spectroscopic and photometric observations of unidentified ultraviolet variable objects in the GUVV-2.Catalog

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Research in Astronomy and Astrophysics 2011年第7期11卷 833-842页

作者： You li Jing wang Jian-Yan Wei Xiang-Tao He Department of Astronomy Beijing Normal University Beijing 100875 China national astronomical {2. Chinese Academy of Sciences Beijing 100012 China

An NUV-optical diagram composed from sources from the second Galaxy Evolution Explorer（GALEX） Ultraviolet Variability（GUVV-2. Catalog provides us with a method to tentatively classify the unknown GUVV-2.sources by their NUV-optical *** the purpose of testing the correctness and generality of the method,we carry out a program on the spectroscopic observations of the unidentified GUVV-2.*** spectroscopic identification of these 37 sources are 19 type-A to-F stars,10 type-G to-K stars and 7 M dwarf stars together with an *** also pre{2.t the light curves in the R-band for two RR Lyrae star candidates selected from the NUV-optical diagram,both of which undergo cyclic *** their light curves and colors,we classify them as RR Lyrae *** confirm the re-sults,we show a color-color diagram for the 37 newly identified spectroscopic objects compared with previously identified ones,which are consistent with our previous re-sults,indicating that the ultraviolet variable sources can initially be classified by their NUV/optical color-color diagram.

关键词： stars:variables:general—galaxies:active—methods:observational—ultraviolet emission

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An unexpected stereochemical effect of thio-substituted Asp in native chemical ligation

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chinese Chemical Letters 2024年第8期35卷 278-281页

作者： Min Fu Pan He sen Zhou Wenqiang liu Bo Ma Shiying Shang Yaohao li Ruihan wang Zhongping Tan State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Center of Pharmaceutical Technology School of Pharmaceutical SciencesTsinghua UniversityBeijing 100084China Chemical Engineering College Hebei Normal University of Science and TechnologyQinhuangdao 066600China

This study presents an unexpected finding that the cis isomer of β-thio-Asp exhibits higher ligation ac-tivity than the trans *** discovery sheds light on the intricate nature of native chemical ligation and highligh... 详细信息

关键词： Native chemical ligation Stereochemistry ligation activity β-Thio-Asp Intramolecular hydrogen bond

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Triaxial ellipsoid models of the Moon based on the laser altimetry data of Chang'E-1

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Science china Earth sciences 2010年第11期53卷 1594-1601页

作者： wang WenRui1,2.3, {2. Fei1, {2.U JianJun1, REN Xin2. ZOU XiaoDuan2.3, MU {2.ng{2.2. YAN JianGuo1, ZOU Yong{2.ao2. ZHANG HongBo2. Lü Chang2. {2.U JianZhong2. ZUO Wei2. SU Yan2. WEN WeiBin2. BIAN Wei2. wang Min2. {2. ChunLai2.& OUYANG ZiYuan2.1 School of Geodesy and Geomatics, Wuhan University, Wuhan 430079, china 2.{12. astronomical Observatory of chinese Academy of sciences, beijing 100012, china 3 Graduate School of chinese Academy of sciences, beijing 100049, china 1. School of Geodesy and Geomatics Wuhan University Wuhan 430079 China2. National Astronomical Observatory of Chinese Academy of Sciences Beijing 100012 China3. Graduate School of Chinese Academy of Sciences Beijing 100049 China

Lunar geodetic parameters, which play an important role in lunar exploration, can be calculated from the gravity and topography data. With the CE-1 altimetry data and LP gravity model, we calculate such geodetic parameters as the principle moment of inertia, the principle inertia axes, equatorial radius, polar radius, mean radius, flattening and offset between center of mass and center of figure (DCOM-COF). According to the CE-1 altimetry data and the above geodetic parameters, a tri-axial ellipsoid (CE-1-LAM-GEO) and a tri-axial level ellipsoid (CE-1-LAM-LEVEL) are calculated individually, providing mass center and figure center offset (DCOM-COF) and parameters more reliable in direction and magnitude.

关键词： Chang’E-1 laser altimetry data lunar ellipsoid lunar gravity

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Support Vector Machine combined with K-Nearest Neighbors for Solar Flare Forecasting

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chinese Journal of Astronomy and Astrophysics 2007年第3期7卷 441-447页

作者： rong li Hua-Ning {2. Han He Yan-Mei Cui Zhan-Le Du national astronomical {2. Chinese Academy of Sciences Beijing 100012

A method combining the support vector machine （SVM） the K-Nearest Neighbors （KNN）, labelled the SVM-KNN method, is used to construct a solar flare forecasting model. Based on a proven relationship between SVM and KNN, the SVM-KNN method improves the SVM algorithm of classification by taking advantage of the KNN algorithm according to the distribution of test samples in a feature space. In our flare forecast study, sunspots and 10cm radio flux data observed during Solar Cycle 2. are taken as predictors, and whether an M class flare will occur for each active region within two days will be predicted. The SVM- KNN method is compared with the SVM and Neural networks-based method. The test results indicate that the rate of correct predictions from the SVM-KNN method is higher than that from the other two methods. This method shows promise as a practicable future forecasting model.

关键词： Sun flare - Sun sunspot - Sun activity - Sun magnetic fields

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