检索结果-南通市图书馆

Defect-modulated synthesis and optoelectronic properties in chemical vapor deposited CsPbBr_(3) microplates

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第5期17卷 4610-4615页

作者： Yanan Bao Hengshan Wang Meiqi An Huayi Tang Jing Li Jianliang Li Conghui Tan Yingmin luo jiao Xu Yiming Yang School of Microelectronics Dalian University of TechnologyDalian 116024China Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024China

The remarkable optoelectronic features of halide perovskite promote their potential applications in semiconductor devices beyond solar cells,which require high-quality single crystals with controlled defect ***,we investigated the synthesis mechanism of chemical vapor deposited single-crystalline all-inorganic perovskite microplates(MPs),and reported a defect-modulated photocurrent which is closely related to the growth sequence of the *** MP synthesis initiates from island-like nano-disks,and subsequently transits to a layer-by-layer fashion,resulting in a defect-rich area at the center of the *** elevated temperatures,these central defects may be thermally activated and become highly mobile,leading to photoluminescence quenching and degression of local and overall optoelectronic attributes,as evidenced by the spatial resolved optical and electrical scanning probe ***,this work shines light on the formation,proliferation and dynamics of defects in perovskites,and offers guidance for preparation of high-quality perovskites micro-crystals for functional semiconductor devices with high temperature stability.

关键词： halide perovskites nanomaterials optoelectronics scanning photocurrent microscope chemical vapor deposition

Pollen-expressed RLCKs control pollen tube burst

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plant Communications 2024年第8期5卷 147-156页

作者： Yin-jiao Xu Ting luo Peng-Min Zhou Wei-Qi Wang Wei-Cai Yang Hong-Ju Li Center for Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Center for Molecular Agrobiology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina Key Laboratory of Seed Innovation Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina

In angiosperms,the pollen tube enters the receptive synergid cell,where it ruptures to release its cytoplasm along with two sperm *** interaction is complex,and the exact signal transducers that trigger the bursting of pollen tubes are not well *** this study,we identify three homologous receptor-like cytoplasmic kinases(RLCKs)expressed in pollen tubes of Arabidopsis,Delayed Burst 1/2/3(DEB1/2/3),which play a crucial role in this *** genes produce proteins localized on the plasma membrane,and their knockout causes delayed pollen tube burst and entrance of additional pollen tubes into the embryo sac due to fertilization *** show that DEBs interact with the Ca^(2+)pump ACA9,influencing the dynamics of cytoplasmic Ca^(2+)in pollen tubes through *** results highlight the importance of DEBs as key signal transducers and the critical function of the DEB-ACA9 axis in timely pollen tube burst in synergids.

关键词： Pollen tube burst RLCKs Calcium signaling/transport Double fertilization

Should we perform sigmoidoscopy for colorectal cancer screening in people under 45 years?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第4期16卷 1248-1255页

作者： Waiian Leong Jia-Qi Guo Chun Ning Fei-Fei luo Rui jiao Dong-Ye Yang Division of Gastroenterology&Hepatology The University of Hong Kong-Shenzhen HospitalShenzhen 518053Guangdong ProvinceChina Department of Accident&Emergency The University of Hong Kong-Shenzhen HospitalShenzhen 518053Guangdong ProvinceChina Department of Anatomical Pathology The University of Hong Kong-Shenzhen HospitalShenzhen 518053Guangdong ProvinceChina Endoscopy Center The University of Hong Kong-Shenzhen HospitalShenzhen 518053Guangdong ProvinceChin

BACKGROUND The strategy for preventing colorectal cancer is screening by colonoscopy,which offers a direct way for detection and removal of adenomatous polyps(APs).American College of Gastroenterology guidelines recommend that people aged≥45 years should undergo colonoscopy;however,how to deal with people aged≤45 years is still *** To compare the prevalence of APs and high-grade neoplasia between the left and right colon in patients≤45 *** A retrospective observational study was conducted at a single tertiary III hospital in *** study included patients aged 18-45 years with undergoing initial colonoscopy dissection and pathological diagnosis AP or high-grade neoplasia between February 2014 and January *** number of APs in the entire colon while screening and post-polypectomy surveillance in following 1-3 years were *** A total of 3053 cases were *** prevalence of APs in the left and right colon was 55.0%and 41.6%,respectively(OR 1.7,95%CI 1.6-2.4;P3 polyps(14.1%;OR 0.3,95%CI 0.1-0.6;P<0.05).CONCLUSION This study suggests that flexible sigmoidoscopy would be an optimal approach for initial screening in people aged≤45 years and would be a more cost-effective and safe strategy.

关键词： Adenomatous polyps High-grade neoplasia Colonoscopy Flexible sigmoidoscopy

Method for the height measurement of agricultural implements based on variable parameter Kalman filter

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Agricultural and Biological Engineering 2024年第2期17卷 193-199页

作者： Gaolong Chen Xiwen luo Lian Hu Pei Wang Jie He Dawen Feng Weicong Li Jinkang jiao College of Engineering South China Agricultural UniversityGuangzhou 510642China Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510642China Guangdong Provincial Key Laboratory of Agricultural Artificial Intelligence(GDKL-AAI) Guangzhou 510642China

To improve the GNSS receiver’s accuracy,continuity,and stability in measuring the height of agricultural implements,this study proposed a variable-parameter Kalman filter(VPKF)algorithm based on GNSS and accelerometer to estimate the height of the implements *** VPKF was verified,and its accuracy was evaluated by parallel rail platform and field *** the parallel rail test results,when the GNSS receiver was in real-time kinematic(RTK)positioning and the time delay of differential correction data(TDDCD)was less than or equal to 4 s,the root mean square error(RMSE)of the VPKF estimation was 9.82 *** RMSE of the GNSS measurement was 18.85 *** the GNSS receiver lost differential correction data within 28 s,the absolute error of VPKF was less than 30 mm,and the RMSE was 16.93 *** field test results showed that when the GNSS receiver was in RTK positioning and the TDDCD was less than or equal to 4 s,the RMSE of VPKF estimation was 13.43 mm,and the GNSS measurement was 14.56 *** the GNSS receiver lost differential correction data within 28 s,the RMSE of the VPKF estimate was 15.22 *** results show that VPKF can optimally estimate implement height with better ***,the VPKF can obtain a more accurate,continuous,and stable height of the implement,and increase the application scenarios of the GNSS receiver to measure the implement height.

关键词： agricultural implement height Kalman filter GNSS accelerometer

Two-dimensional silica enhanced solid polymer electrolyte for lithium metal batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2024年第2期85卷 146-154页

作者： Zhihong luo Weiyong Li Chong Guo Ya Song Mingxia Zhou Yan Shi Jing Xu Long Li Bin Shi Quansheng Ouyang jiao-jing Shao Guangmin Zhou School of Materials and Metallurgy Guizhou UniversityGuiyang550025China State Key Laboratory of Advanced Chemical Power Sources Zunyi563003China Graphene Materials Engineering Research Center of Guizhou Colleges and Universities Guiyang550025China Tsinghua-Berkeley Shenzhen Institute&Tsinghua Shenzhen International Graduate Schoo Tsinghua UniversityShenzhen518055China

Solid polymer electrolytes(SPEs)are promising substitutes for current flammable liquid electrolytes to achieve high-safety and high-energy-density lithium metal *** oxide(PEO)based solid polymer electrolytes have attracted increasing attention because of their excellent flexibility,manufacturability,light weight,and low-cost processing,while they often suffer from low ionic con-ductivity at room temperature,low lithium transference number and unsatisfactory interfacial resis-tance,which largely restrain their practical ***,two-dimensional holey silica nanosheets(2D-HSN)as the fillers,together with LiNO_(3) as the electrolyte additive,are introduced in a PEO/poly(-vinylidene fiuoride-co-hexafluoropropylene)(PVDF-HFP)blended polymer matrix to obtain a *** incorporation of HSN filler creates supplementary channels for lithium ion migration and lowers the crystallinity of the polymer,thereby facilitating the movement of lithium *** HSN-based SPE demonstrates higher ionic conductivity up to 3.7 x 10-4 S cm-1 at 30℃,larger Li+transference number close to 0.34,and more stable lithium plating/stripping than that without the fillers,and HSN can promote the formation of more stable solid electrolyte interphase(SEI)*** as-assembled LiFePO4||Li batteries deliver a high specific capacity of 159 mA h g-1 with the capacity retention of 95.5%after 200 cycles at 30℃,as well as superior rate performance and cycling stability compared to that using the blank SPE.

关键词： Vermiculite nanosheets Two-dimensional silica Solid polymer electrolytes FillersLithium metal batteries

Rhodium-catalyzed Doyle-Kirmse rearrangement reactions of sulfoxoniun ylides

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第4期35卷 363-366页

作者： Ying-Di Hao Zhi-Qian Lin Xiao-Yu Guo jiao Liang Can-Kun luo Qian-Tao Wang Li Guo Yong Wu Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Department of Medicinal Chemistry Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China

Doyle-Kirmse rearrangement reactions have received continuous attention as an important method for constructing complex chemical structures. Herein, we disclosed an efficient rhodium-catalyzed DoyleKirmse rearrangement reaction, which can simultaneously construct C–C bonds and C–X(X = S/Se) bonds using sulfoxonium ylides as starting materials to obtain sulfur-or selenium-containing compounds. This strategy is characterized by the safer and greener carbene precursor, high yields and broad substrate scope, possessing a wide range of application.

关键词： Sulfoxonium ylides Rhodium(Ⅱ)-catalyzed Carbene Rearrangement reactions One-pot process

Adaptive strategies of high and low nucleic acid prokaryotes in response to declining resource availability and selective grazing by protozoa

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2024年第6期67卷 1872-1884页

作者： Chen HU Liuqian YU Xiaowei CHEN Jihua LIU Yao ZHANG John BATT Xilin XIAO Qiang SHI Rui ZHANG Tingwei luo Nianzhi jiao Dapeng XU College of the Environment and Ecology Xiamen UniversityXiamen 361102China State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesFujian Key Laboratory of Marine Carbon SequestrationXiamen UniversityXiamen 361102China Joint Lab for Ocean Research and Education(LORE)of Dalhousie University Canadaand Shandong University and Xiamen UniversityXiamen 361102China Earth Ocean and Atmospheric Sciences ThrustThe Hong Kong University of Science and Technology(Guangzhou)Guangzhou 510000China Institute of Marine Science and Technology Shandong UniversityQingdao 266237China Department of Oceanography Dalhousie UniversityHalifaxNova Scotia B3H 4R2Canada Institute for Advanced Study Shenzhen UniversityShenzhen 518060China Carbon Neutral Innovation Research Center Xiamen UniversityXiamen 361102China

Prokaryotes play a fundamental role in global ocean biogeochemical ***,how the abundance and metabolic activity of ecologically distinct subgroups(i.e.,high nucleic acid(HNA)and low nucleic acid(LNA)cells),and their regulating factors,change in response to changing marine environmental conditions remains poorly ***,we delved into the time-evolving dynamic responses of the HNA and LNA prokaryotic subgroups to declining resource availability and selective grazing by protozoa by conducting a 73-day incubation experiment in a large-volume(117,000 L)macrocosm that facilitates community-level *** found that the metabolic activity of the HNA subgroup was higher than that of the LNA subgroup when the macrocosm was resource replete but that the HNA subgroup declined more rapidly than the LNA subgroup as the resources became increasingly scarce,leading to a steadily increasing contribution of LNA cells to prokaryotic ***,as resources in the macrocosm became limited,protozoan grazing preference shifted from the HNA to the LNA subgroup and the contributions of the LNA subgroup to the carbon flow within the macrocosm *** findings highlight the resilience of LNA cells in resource-limited environments,illuminate the critical role of selective grazing by protozoa in balancing distinct prokaryotic subgroups under changing resource conditions,and demonstrate the complex and adaptive interactions between protozoa and prokaryotes across diverse environmental contexts.

关键词： Microbial loop Macrocosm experiment Prokaryote Top-down and bottom-up controls Carbon flow

Characterization and Monitoring of Transient Enamine Radical Intermediates in Photoredox/Chiral Primary Amine Synergistic Catalytic Cycle

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

CCS Chemistry 2024年第10期6卷 2420-2426页

作者： Shixue Zhang Liang Cheng Jian-Qing Qi Zongbin Jia Long Zhang Lei jiao Xingwei Guo Sanzhong luo Center of Basic Molecular Science(CBMS) Department of ChemistryTsinghua UniversityBeijing 100084

Enamine-derived radicals are crucial intermediates in singly occupied molecular orbital(SOMO)***,observing them directly is elusive and remains a long-standing ***,an advanced time-resolved electron paramagnetic resonance technique was employed to characterize and monitor the key intermediates in photoredox transformations by primary aminocatalysis on a microsecond *** transient enamine radical cation,generated by single electron transfer(SET),and the deprotonated form ofα-imino radical intermediates were directly observed for the first time,both spectroscopically and *** reactions with styrene,enamine radical cation was found to be faster thanα-imino radical by one order of *** revealed the subtle role of deprotonation associated with secondary enamine radical cation in the photoredox transformations by primary aminocatalysis.

关键词： aminocatalysis radical chemistry electron paramagnetic resonance direct observation time-resolved technique

A recyclable method for titanium extraction and oxygen evolution from Ti-bearing slags

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Fundamental Research 2024年第1期4卷 86-94页

作者： Zhenghao Pu Wei Wang Zhe Wang Mingyin Kou Yiwa luo Jianbang Ge Xin Tao Mingyong Wang Shuqiang jiao State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

Despite its existence for more than 80 years,the titanium industry is still challenged by massive carbon emissions,high production costs,and large resource *** than one hundred million tons of Ti-bearing blast furnace slag(TB-slag)has been discarded in China because of the difficulty of reutilization,which requires efficient titanium extraction and recovery *** paper describes a low-cost,carbon-emission-free method for Ti extraction and oxygen evolution via molten oxide electrolysis(MOE)vacuum *** a comprehensive analysis of the binding energies and activities of liquid metals,the highlights of our study are as follows.1)Sb has the best preferential deposition of Ti among a series of high-Ti-affinitive liquid metal cathodes(Cu,Ni,Pb,Sn,and Sb).2)The Ir anode was first used in TB-slag with IrO_(2) formed on its surface to protect it from further corrosion.3)An alloy containing Ti and Ca can be obtained by MOE,and Ti and Ca metals can be refined by further vacuum distillation.4)A closed loop is formed in the overall process owing to the recyclable Sb cathode and continuous feeding of TB-slag into the *** simple,low-cost,and environmentally friendly method can realize the efficient utilization of Ti resources and achieve carbon neutrality.

关键词： Titanium Molten oxide electrolysis Inert anodeLiquid cathode Depolarization