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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 wang 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

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 & wang Tuanhua1 1. institute of Geology, china Seismological Bureau, beijing 100029, china 2. institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, 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_2O+Na_2O = 5%—11%, especially for K_2O) as well asvolatiles such as H_2O 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_2O > 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.

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(P208,INET-1,P218,USTB-1 and P227)and γ,δ-substituent group(P218,P2132 and Cyanex 272).For β-substituent group extractants,their loading capacities are in the order P208(299.7 mg/L)≈INET-1(299.5 mg/L)>P218(270.8 mg/L)>>USTB-1(163.1 mg/L)>P227(151.4 mg/L),while their anti-emulsification/gelation performances are just in the opposite order P227>USTB-1>P218>P208≈INET-1 under the studied *** γ,δ-substituent group extractants,their loading capacities are in the order P218(270.8 mg/L)>P2132(192.3 mg/L)>Cyanex272(131.7 mg/L),while the anti-emulsification performance of P218 is better than those of P2132 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

Quantitative estimation of the shrub canopy LAI from atmosphere-corrected HJ-1 CCD data in Mu Us Sandland

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Science china Earth sciences 2010年第S1期53卷 26-33页

作者： CHEN Wei1,2,CAO ChunXiang1,HE QiSheng1,2,GUO HuaDong3,ZHANG Hao1,2,LI RenQiang4,ZHENG Sheng1,2,xu Min1,2,GAO Mengxu1,2,ZHAO Jian1,2,LI Sha1,ni XiLiang1,2,JIA HuiCong1,JI Wei1,TIAN Rong1,2,LIU Cheng1,2,ZHAO YuXing5 & LI JingLu6 1 State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the institute of Remote Sensing Applications of chinese academy of sciences and beijing Normal University,beijing 100101,china 2 Graduate University of chinese academy of sciences,beijing 100049,china 3 Center for Earth Observation and Digital Earth,chinese academy of sciences,beijing 100190,china 4 china Key Laboratory of Ecological Network Observation and Modeling,institute of Geographical sciences and Natural Resources Research,chinese academy of sciences,beijing 100101,china 5 Ordos Forestry Sand Control Science institute,Dongsheng 017000,china 6 Inner Mongolia Biomass Thermoelectricity Limited Company,Wushen 017300,china State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Graduate University of chinese academy of sciences Beijing China Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing China china Key Laboratory of Ecological Network Observation and Modeling Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Ordos Forestry Sand Control Science institute Dongsheng China Inner Mongolia Biomass Thermoelectricity Limited Company Wushen China

The leaf area index(LAI) is an important ecological parameter that characterizes the interface between vegetation canopy and the *** addition,it is used by most process-oriented ecosystem *** paper investigates the potential of HJ-1 CCD data combined with linear spectral unmixing and an inverted geometric-optical model for the retrieval of the shrub LAI in Wushen Banner of Inner Mongolia in the Mu Us ***(Moderate Resolution Atmospheric Radiance and Transmittance Model) was used for atmospheric *** was extracted using the threshold of the normalized difference vegetation index,with which water bodies and farmland were separated,in combination with a vegetation map of the People's Republic of china(1:1000000).Using the geometric-optical model,we derive the per-pixel reflectance as a simple linear combination of two components,namely sunlit background and *** fraction of sunlit background is related to the shrub *** the support of HJ-1 CCD data,we employ linear spectral unmixing to obtain the fraction of sunlit background in an atmospherically corrected HJ *** addition,we use the measured shrub canopy structural parameters for shrub communities to invert the geometric-optical model and retrieve the pixel-based shrub *** total,18 sample plots collected in Wushen Banner of Inner Mongolia are used for *** results of the shrub LAI show good agreement with R2 of 0.817 and a root-mean-squared error of 0.173.

关键词： shrub leaf area index inversion HJ-1 data geometric-optical model MODTRAN Mu Us Sandland

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

Scale effects of leaf area index inversion based on environmental and disaster monitoring satellite data

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Science china Earth sciences 2010年第S1期53卷 92-98页

作者： ZHANG Hao1,LI XiaoWen1,2,CAO ChunXiang1,YANG Hua2,GAO Mengxu1,3,ZHENG Sheng1,3,xu Min1,3,XIE DongHui2,JIA HuiCong1,JI Wei1,ZHAO Jian1,3,CHEN Wei1,3 & ni XiLiang1,3 1 State Key Laboratory of Remote Sensing Science,Jointly Sponsored by institute of Remote Sensing Applications,chinese academy of sciences and beijing Normal University,beijing 100101,china 2 State Key Laboratory of Remote Sensing Science,Jointly Sponsored by beijing Normal University and institute of Remote Sensing Applications of chinese academy of sciences,beijing 100875,china 3 Graduate University of chinese academy of sciences,beijing 100049,china State Key Laboratory of Remote Sensing Science Jointly Sponsored by Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Beijing China State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications of Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

The spatial distribution of sub-pixel components has an impact on retrieval accuracy,and should be accounted for when inverting a three-dimensional adiative transfer model to retrieve leaf area index(LAI).To investigate this effect,we constructed three realistic scenarios with the same LAI values and other properties,except that the simulated plants had different *** implemented the radiosity method to subsequently produce synthetic bidirectional reflectance factor(BRF) datasets based upon these simulated *** inversion was conducted using these data,which showed that spatial distribution affects retrieval *** inversion was also conducted for LAI based on charge-coupled device(CCD) data from the Environment and Disaster Monitor Satellite(HJ-1),which depicted both forest and drought-resistant crop land *** showed that heterogeneity in coarse-resolution remote sensing data is the main error source in LAI *** spatial distribution of global fractal dimension index,which can be used to describe the area of sub-pixel components and their spatial distribution modes,shows good consistency with the coarse resolution LAI inversion error.

关键词： HJ-1 leaf area index scale effect spatial distribution

Preparation of Pt/K_2La_2Ti_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 institute 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 K2La2Ti3O10 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 K2La2Ti3O10 as a co-catalyst with different methods. The dispersion of platinum on K2La2Ti3O10 was determined with HOT method. The photocatalytic activity of Pt/K2La2Ti3O10 was studied. This catalyst showed much higher activity in hydrogen evolution reaction than ni/K2La2Ti3O10. The effects of different amounts of loaded platinum and several preparation methods were evaluated. The best achieved hydrogen evolution rate was 233.88 μmol·h?1 by Pt(2%)/K2La2Ti3O10. A possible band structure and mechanism were discussed based on the results.

关键词： photocatalysis hydrogen platinum K_2La_2Ti_3O_(10) support

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 wang 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

The RNA binding protein EHD6 recruits the m^(6)A reader YTH07 and sequesters OsCOL4 mRNA into phase-separated ribonucleoprotein condensates to promote rice flowering

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Molecular Plant 2024年第6期17卷 935-954页

作者： Song cui Peizhe Song Chaolong wang Saihua Chen Benyuan Hao Zhuang xu Liang Cai xu Chen Shanshan Zhu Xiangchao Gan Hui Dong Yuan Hu Liang zhou Haigang Hou Yunlu Tian Xi Liu Liangming Chen Shijia Liu Ling Jiang Haiyang wang Guifang Jia Shirong zhou Jianmin Wan State Key Laboratory for Crop Genetics&Germplasm Enhancement and Utilization Zhongshan Biological Breeding LaboratoryNational Observation and Research Station of Rice Germplasm ResourcesNanjing Agricultural UniversityNanjing 210095China State Key Laboratory for Crop Gene Resources and Breeding Institute of Crop ScienceChinese Academy of Agricultural SciencesBeijing 100081China Synthetic and Functional Biomolecules Center Beijing National Laboratory for Molecular SciencesKey Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking-Tsinghua Center for Life SciencesBeijing Advanced Center of RNA BiologyPeking UniversityBeijingChina Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding Agricultural College of Yangzhou UniversityYangzhou 225009China Max Planck institute for Plant Breeding Research Carl-von-Linne´-Weg 1050829 KolnGermany

N6-Methyladenosine(m^(6)A)is one of the most abundant modifications of eukaryotic mRNA,but its comprehensive biological functionality remains further *** this study,we identified and characterized a new flowering-promoting gene,EARLY HEADING DATE6(EHD6),in ***6 encodes an RNA recognition motif(RRM)-containing RNA binding protein that is localized in the non-membranous cytoplasm ribonucleoprotein(RNP)granules and can bind both m^(6)A-modified RNA and unmodified RNA *** found that EHD6 can physically interact with YTH07,a YTH(YT521-B homology)domain-containing m^(6)A *** showed that their interaction enhances the binding of an m^(6)A-modified RNA and triggers relocation of a portion of YTH07 from the cytoplasm into RNP granules through phase-separated *** these condensates,the mRNA of a rice flowering repressor,CONSTANS-like 4(OsCOL4),becomes sequestered,leading to a reduction in its protein abundance and thus accelerated flowering through the Early heading date 1 *** together,these results not only shed new light on the molecular mechanism of efficient m^(6)A recognition by the collaboration between an RNA binding protein and YTH family m^(6)A reader,but also uncover the potential for m^(6)A-mediated translation regulation through phaseseparated ribonucleoprotein condensation in rice.

关键词： N6-methyladenosine m^(6)A EHD6 YTH domain-containing protein phase separation heading date