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A super-resolution algorithm for synthetic aperture radar based on modified spatially variant apodization

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Science china(Physics,Mechanics & Astronomy) 2011年第2期54卷 355-364页

作者： ni chong {2. yanfei xu xianghui zhou changyi cui pengfei institute of electronics Chinese Academy of SciencesBeijing 100190 China Graduate University of the chinese academy of sciences Beijing 100190 China

The existing spatially variant apodizations(SVAs) either cannot depress the sidelobes effectively or reduce the energy of the *** improve this,a modified SVA(MSVA) is put forward in this paper,which expands the traditional filter from 3-taps to 5-taps and sets relevant parameters according to different sampling rates to get the excellent result that satisfies constrained optimization theory.A modified super-SVA is also presented,which compares the result after the iteration with the original signal and makes the one whose amplitude is smaller as the initial value of the next *** method can eliminate the sidelobes produced by the intermediate operation,so that the following bandwidth extrapolation is more ***-MSVA is presented based on the modified SVA and modified super-SVA,which is suitable for any Nyquist sampling rate,can extrapolate the signal bandwidth many times through iteration with a commensurate improvement in resolution,as demonstrated by the result of the experiment.

关键词： synthetic aperture radar sidelobe suppression super-resolution SVA

Loading capacity and emulsification phenomena of HREE extraction by dialkylphosphinic acids with different β,γ,δ-substituents

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Journal of Rare Earths 2024年第1期42卷 191-199,I0007页

作者： Junlian wang Guodong xu Wen xu Jianguo cui Yufu Chen Ziyong Chang School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines Beijing100083China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou014030China

The relationship between dialkylphosphinic acid structure and their loading capacity for HREEs and emulsification phenomena has rarely been *** this paper,we took Lu extraction as an example to study the effect of β,γ,δ-substituents of dialkylphosphinic acids on their loading capacity and anti-emulsification performance for *** discuss conveniently,the dialkylphosphinic acids were classified into two groups:β-substituent group(P2.8,INET-1,P2.8,USTB-1 and P2.7)and γ,δ-substituent group(P2.8,P2.32.and Cyanex 2.2..For β-substituent group extractants,their loading capacities are in the order P2.8(2.9.7 mg/L)≈INET-1(2.9.5 mg/L)>P2.8(2.0.8 mg/L)>>USTB-1(163.1 mg/L)>P2.7(151.4 mg/L),while their anti-emulsification/gelation performances are just in the opposite order P2.7>USTB-1>P2.8>P2.8≈INET-1 under the studied *** γ,δ-substituent group extractants,their loading capacities are in the order P2.8(2.0.8 mg/L)>P2.32.192.3 mg/L)>Cyanex2.2.131.7 mg/L),while the anti-emulsification performance of P2.8 is better than those of P2.32.and Cyanex *** loading capacity data given in the parentheses are obtained through repeatedly extracting Lu from ~4×10^(-4)mol/L of Lu aqueous feed solution with initial pH of 2.40 by 0.01 mol/L extractant at phase ratio A/O of 1:1.

关键词： Heavy rare earth element Dialkylphosphinic acid Extraction Loading capacity Emulsification

A strategy based on water soluble coal tar pitches to construct MnO_(2.@C composite materials with high electrochemical performance

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Science china(Technological sciences) 2024年第1期67卷 311-320页

作者： LIU Bo wang Kun GUO ZhaoQi HAN BeiBei xu GuiYing JU DongYing AN BaiGang LI YongCheng {2. ZhenYong zhou WeiMin Key Laboratory of Energy Materials and Electrochemistry Research Liaoning Province University of Science and Technology LiaoningAnshan 114051China Advanced Science Research Laboratory Saitama Institute of TechnologyFusaiji 1690Japan Liaoning Starry Sky Sodium Battery Co. Ltd.Anshan 114051China Sinosteel Anshan Research institute of Thermo-Energy Co. Ltd.Anshan 114051China State Key Laboratory of Marine Resource Utilization in South china Sea Hainan Provincial Key Lab of Fine ChemistrySchool of Chemical Engineering and TechnologyHainan UniversityHaikou 570228China Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China

The water soluble coal tar pitches(WS-CTPs)were successfully prepared and used to construct the MnO_(2.@C composite materials by a hydrothermal *** is interestingly observed that the structures and morphologies of MnO_(2.@C materials can be controlled by controlling the dosages of WS-CTPs and ***,it is aware that MnO_(2.exists in the MnO_(2.@C materials in an amorphous *** with MnO_(2.,MnO_(2.@C materials output a remarkable improvement in electrochemical *** instance,MnO_(2.@C-0.3 shows the storage capacity at 965.7 mA h g^(−1)after 300 cycles at a current density of 0.1 A g^(−1).In addition,after 600 cycles at a current density of 1.0 A g^(−1),the storage capacity of MnO_(2.@C-0.3 still keeps 450.3 mA h g^(−1),indicating that MnO_(2.@C-0.3 owns tremendous cycle stability at a high current *** view of the fact that the coal tar pitches possess great cost advantages,the strategy of using WS-CTPs as a carbon source to cover the metal oxides is a competitive way to expand the application of metal oxides in the fabrication of electrodes of LIBs.

关键词： water soluble coal tar pitches MnO_(2. composite materials lithium ion batteries(LIBs) energy storage systems(ESSs) coal tar pitches

Si-and alkali-rich melt inclusions in minerals of mantle peridotites from eastern china:Implication for lithospheric evolution

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Science china Earth sciences 2006年第1期49卷 43-49页

作者： FAN Qicheng1, SUI Jianli2. xu Ping2. LI ni1, SUN Qian1 & {2. Tuanhua1 1. institute of Geology, china Seismological Bureau, Beijing 10002., china 2. institute of Geology and Geophysics, chinese academy of sciences, Beijing 10002., china institute of Geology China Seismological Bureau Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Minerals of spinel- and garnet-facies mantle xenoliths entrained in Cenozoicbasalts from eastern china (North china, Northeastern china and Southeastern china coastal area)contains lots of melt inclusions. Studies on these melt inclusions show that the glass inclusionsare rich in SiO_2.(60%—68%) and alkalis (K_2.+Na_2. = 5%—11%, especially for K_2.) as well asvolatiles such as H_2. and CO_2.(2.—7%), which belong to dacites and andesites of the high-K calcicalkali series rocks with few shoshonites. High Al and Ca diopside in melt inclusion is the productof melt crystallization at high temperature and pressure, rather than the product ofdevitrification. Results show that these K-rich (in general K_2. > 3%) intermediate-acidic silicatemelt inclusions have characteristics of continent without a genetical link to host basalts and theirphenocrystic minerals. Thus, these trapped melt inclusions represent melts of Mesozoic lithosphericmantle-crust interaction and imply that the continental lithospheric mantle beneath eastern chinahad undergone fragmentation and recreation processes during the Mesozoic and Cenozoic periods. Thisresult undoubtly provides important implication for the evolution of sub-continental lithospherebeneath eastern china. We propose that these Si- and alkalis-rich melts should be responsible forthe mantle chemical heterogeneity underneath eastern china.

关键词： Si- and alkali-rich melt inclusion, mantle peridotite, lithospheric evolution, eastern china.

Molecular characterization and structure basis of a malonyltransferase with both substrate promiscuity and catalytic regiospecificity from Cistanche tubulosa

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2333-2348页

作者： Xiao Liu Yuyu Liu Xiping xu Wenqian Huang Yaru Yan Yingxia wang Weisheng Tian Ting Mo Xiaoxue cui Jun Li She-Po Shi pengfei Tu Modern Research Center for Traditional chinese Medicine Beijing Research Institute of Chinese MedicineBeijing University of Chinese MedicineBeijing 100029China Modern Research Center for Traditional chinese Medicine School of Chinese Materia MedicaBeijing University of Chinese MedicineBeijing 100029China

Enzymatic malonylation of natural glycosides provides a promising alternative method for drug-like malonylated glycosides ***,the catalytic potential and structural basis of plant malonyltransferase are far from being fully *** work identified a new malonyltransferase CtMaT1 from Cistanche *** displayed unprecedented mono-and/or di-malonylation activity toward diverse glucosides with different aglycons.A“one-pot”system by CtMaT1 and a malonyl-CoA synthetase was established to biosynthesize nine new malonylated *** investigations revealed that CtMaT1 possesses an adequately spacious acyl-acceptor pocket capable of accommodating diverse ***,it recognizes malonyl-CoA through strong electrotactic and hydrogen ***/MM calculation revealed the H167-mediated SN2.reaction mechanism of CtMaT1,while dynamic simulations detected the formation of stable hydrogen bonds between the glucose-6-OH group and H167,resulting in its high malonylation *** energy profiles of two isomeric glycosides highlighted lower reaction energy barriers towards glucoside substrates,emphasizing CtMaT1's preference for ***,a mutant CtMaT1H36A with notably increased di-malonylation activity was *** underlying molecular mechanism was illuminated through MM/GBSA binding free energy *** study significantly advances the understanding of plant acyltransferases from both functional and protein structural perspectives,while also providing a versatile tool for enzymatic malonylation applications in pharmacology.

关键词： Plant acyltransferase Malonyltransferase Malonylated glycosides Enzymatic catalysis Enzyme promiscuity

Hot Deformation Behavior and Workability of a New ni–W–Cr Superalloy for Molten Salt Reactors

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1453-1466页

作者： Long Liu Zijian zhou Jie Yu Xinguang wang Chuanyong {2. Rui Zhang Yizhou zhou Xiaofeng Sun Shi‑Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Fushun Special Steel Co. LtdFushun 113000China

The hot deformation behavior of a newly developed ni–W–Cr superalloy for use in 800℃molten salt reactors(MSRs)was looked into by isothermal compression tests in the temperature range of 1050–12.0℃with a strain rate of 0.001–1 s^(−1)under a true strain of *** Arrhenius-type model for the ni–W–Cr superalloy was constructed by fitting the corrected flow stress *** this model,the effect of dispersion of solid solution elements during thermal deformation on microstructure evolution was considered,as well as the effects of friction and adiabatic heating on the temperature and strain rate-dependent variation of flow *** hot deformation activation energy of the ni–W–Cr superalloy was 32. kJ/mol,which was less than that of the Hastelloy N alloy(currently used in MSRs).According to the rectified flow stress data,processing maps were *** conjunction with the corresponding deformation microstructures,the flow instability domains of the ni–W–Cr superalloy were determined to be 1050–1160℃/0.03–1 s^(−1)and 1170–12.0℃/0.001–0.09 s^(−1).In these deformation conditions,a locally inhomogeneous microstructure was caused by flow-i.e.,incomplete dynamic recrystallization and hot working parameters should avoid sliding into these *** ideal processing hot deformation domain for the ni–W–Cr superalloy was determined to be 1170–12.0℃/0.6–1 s^(−1).

关键词： ni-W-Cr Superalloy Hot deformation behavior Constitutive equation Processing map Microstructure evolution

High-resolution remote thermometry based on Bi^(3+)-doped 0D zinc halide hybrids

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Science china Chemistry 2024年第8期67卷 2599-2605页

作者： cui-Mi Shi Shu-Hua xue Jin-Yun {2. Liang-Jin xu Zhong-ning Chen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science Technology Innovation Laboratory for Optoelectronic Information of ChinaFuzhou 350108China University of chinese academy of sciences Beijing 100049China

Developing highly sensitive optical thermometers is of great significance due to their capability to enable remote and non-contact temperature measurements, rendering them highly applicable in diverse and harsh environments. Herein we report a temperature-dependent phosphor of 0D metal halide hybrid by incorporating Bi^(3+)into the(MePPh_(3))_(2.ZnCl_(4) matrix. Through Bi^(3+)doping,the initially non-luminescent(MePPh_(3))_(2. ZnCl_(4) matrix exhibits a deep-blue emission centered at 453 nm, with a photoluminescence quantum yield(PLQY) of 5.71% and a Stokes shift of 75 nm at room temperature. Experimental characterization demonstrates that exciton-like luminescence of Bi^(3+)is mainly responsible for the blue emission. Single crystals of Bi^(3+)-doped(MePPh_(3))_(2.ZnCl_(4) show an unusual correlation between photoluminescence(PL) lifetime and temperature. Particularly, the dependence of luminescence lifetime on temperature is most remarkable in the temperature range of 80 to 100 K with an exceptional sensitivity up to 0.09 K^(-1), representing one of the best levels for thermometry based on PL decay lifetime. Our work not only provides a viable strategy for designing a novel, environmentally friendly, and stable blue emitter, but also paves the way for precise thermometric application at low temperature.

关键词： lead-free hybrids Bi^(3+)doping blue emission temperature sensing

Preparation of Pt/K_2.a_2.i_3O_(10) and its photo-catalytic activity for hydrogen evolution from methanol water solution

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Science china Chemistry 2006年第2期49卷 162-168页

作者： cui Wenquan1,3, LIU Li2. FENG Liangrong1, xu Chenghua1, LI Zijian1, Lü Shaojie1 & QIU Fali1 1. Chengdu {2. of Organic Chemistry, chinese academy of sciences, Chengdu 610041, china 2. Chemistry Department, Sichuan University of Science & Engineering, Zigong 643033, china 3. Graduate School of the chinese academy of sciences, Beijing 100039, china Correspondence should be addressed to Qiu Fali Chengdu institute of Organic Chemistry Chinese Academy of Sciences Chengdu China Graduate School of the chinese academy of sciences Beijing China Chemistry Department Sichuan University of Science & Engineering Zigong China

A layered perovskite-type oxide K2.a2.i3O10 was prepared with high-temperature solid-state reaction, and characterized with X-ray diffraction (XRD) and ultraviolet-visible diffuse re-flectance spectroscopy (UV-Vis DRS). Platinum was loaded onto K2.a2.i3O10 as a co-catalyst with different methods. The dispersion of platinum on K2.a2.i3O10 was determined with HOT method. The photocatalytic activity of Pt/K2.a2.i3O10 was studied. This catalyst showed much higher activity in hydrogen evolution reaction than ni/K2.a2.i3O10. The effects of different amounts of loaded platinum and several preparation methods were evaluated. The best achieved hydrogen evolution rate was 2.3.88 μmol·h?1 by Pt(2.)/K2.a2.i3O10. A possible band structure and mechanism were discussed based on the results.

关键词： photocatalysis hydrogen platinum K_2.a_2.i_3O_(10) support

Synthesis,Structure and Chemical Bonding of Polyantimony Clusters Containing Coinage Metals[M_(2.Sb_(14)]^(4-)(M=Cu,Ag)

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chinese Journal of Chemistry 2024年第6期42卷 617-622页

作者： Wei-Xing Chen Yu-He xu cui-cui wang Lei Qiao Zi-Yan Guo Wen-Juan Tian Zhong-Ming Sun State Key Laboratory of Element-Organic Chemistry Tianjin Key Lab for Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin300350 China institute of Molecular Science Shanxi UniversityTaiyuanShanxi030006 China

Binary polyantimony clusters,namely[Cu_(2.Sb_(14)]^(4–) and [Ag_(2.Sb_(14)]^(4–),containing coinage metals,were successfully synthesized and characterized,in which two homoatomic Sb73–subunits are bridged by two coinage metals in η^(4):η^(1) and η^(1):η^(1) coordination modes,***[M_(2.Sb_(14)]^(4-),two bridging Cu ions and two Sb atoms form a planar rhombic unit,which was revealed to have antiaromatic properties by theoretical *** electron structure and bonding analysis confirmed the presence of delocalized bonds in the rhombic unit and the metallophilic interaction between two formal M^(+) ions.

关键词： Polyantimony cluster Copper Silver Antiaromaticity Metallophilic interaction Quantum chemical calculations