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Solid-phase impregnation promotes Ce doping in TiO_(2) for boosted denitration of CeO_(2)/TiO_(2) catalysts

Chinese Chemical Letters 2022年第2期33卷 935-938页

作者： Wang Song Jiawei Ji Kai guo Xin Wang Xiaoqian Wei yandi Cai Wei Tan Lulu Li Jingfang Sun Changjin Tang Lin dong School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210093China Key Laboratory of Vehicles Emission Control of Jiangsu Province Center of Modern AnalysisNanjing UniversityNanjing 210093China School of Environment Nanjing Normal UniversityNanjing 210023China School of the Environment Nanjing UniversityNanjing 210093China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

CeO_(2)/TiO_(2)(denoted as Ce Ti) catalysts obtained by solid-phase impregnation behaved better in lowtemperature selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR) than that by conventional wet *** explore the main factors for activity distinction,the texture property,CeO_(2)dispersion and structure changes of TiO_(2)were comprehensively *** was found that surface changes of TiO_(2)had a significant impact on the improved *** results of inductively coupled plasma atomic emission spectrometer (ICP-AES),diffuse reflectance UV-vis spectroscopy (UV-vis-DRS) and Raman,it was inferred that Ce ions were partially incorporated into TiO_(2)lattice,accompanied with the formation of defects and vacancies during solid-phase ***,Ce Ti catalysts from solid-phase impregnation exhibited superiority in adsorption and activation of *** result from monitoring the preparation process indicated that the evolved NO played an important role in promoting Ce doping through depriving oxygen atoms on TiO_(2)*** interaction between Ce and Ti was *** catalyst performed better in NH_(3)-SCR,especially at low temperature,which testified the solid-phase impregnation could be an effective method to modulate interface structure for designing efficient catalyst.

关键词： CeO_(2)/TiO_(2) NH_(3)-SCR Solid-phase impregnation Interfacial interaction NO induced incorporation

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Past and Future of a Type Ia Supernovae Progenitor Candidate HD 265435

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Research in Astronomy and Astrophysics 2023年第1期23卷 83-90页

作者： Wei-Zhong Qi dong-dong Liu Bo Wang Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China

As one of the most useful cosmological distance indicators,type Ia supernovae(SNe Ia)play an important role in the study of ***,the progenitors of SNe Ia are still *** has been suggested that carbonoxygen white dwarf(CO WD)+He subgiant systems could produce SNe Ia through the double-degenerate(DD)model,in which the He subgiant transfers He-rich matter to the primary CO WD and finally evolves to another CO ***,a CO WD+He star system(i.e.,HD 265435)has been discovered to be a new SNe Ia progenitor candidate based on the DD *** orbital period of the system is about 0.0688 days,and the masses of the CO WD and the He star are 1.01±0.15 M_(⊙) and 0.63_(-0.12)^(+0.13)M_(⊙),*** this work,we evolve a large number of primordial binaries to the formation of CO WD+He star systems and investigate the evolutionary history of *** find that HD 265435 may originate from a primordial binary that has a 5.18 M_(⊙) primary and a3.66 M_(⊙) secondary with an initial orbital period of 5200 *** CO WD+He star system would be formed after the primordial binary experiences two common-envelope ejection *** also find that HD 265435 would evolve to a double WD system with a total mass of 1.58 M⊙after a stable mass-transfer process,and the double WD system would merge driven by gravitational wave *** estimate that it would take about 76 Myr for HD 265435 to form an SN *** addition,HD 265435 would be a potential target of space-based gravitational wave observatories(e.g.,LISA,Taiji and TianQin).

关键词： (stars:)binaries(including multiple) close-stars individual(HD 265435)-stars evolution-(stars:)supernovae general-(stars:)white dwarfs

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基于16S rRNA高通量测序的北运河水体及沉积物微生物群落组成对比分析

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环境科学 2021年第11期42卷 5424-5432页

作者：彭柯董志邸琰茗郭逍宇首都师范大学资源环境与旅游学院北京100048 北京大学生命科学学院北京100871 北京市北运河管理处北京101100

微生物群落在沉积物和水生态系统中的物质循环中发挥重要作用,是水生态系统与沉积物之间污染物质交换的桥梁.但非常规补给水源扰动和闸坝、衬砌截流为主的城市河道水体和沉积物微生物对比研究并不多见,基于此以高度人工化的北运河京津... 详细信息

微生物群落在沉积物和水生态系统中的物质循环中发挥重要作用,是水生态系统与沉积物之间污染物质交换的桥梁.但非常规补给水源扰动和闸坝、衬砌截流为主的城市河道水体和沉积物微生物对比研究并不多见,基于此以高度人工化的北运河京津冀段为研究区域,尝试利用高通量测序结果对水体和沉积物微生物群落组成差异进行分析.结果表明,北运河沉积物较水体具有更高的微生物群落α多样性,β多样性则表现为水体中微生物群落较沉积物群落的相似性更高.变形杆菌门(Proteobacteria)丰度在水体与沉积物中无显著差异,且在两种生境条件下均为优势类群.α变形杆菌纲(α-Proteobacteria)、放线杆菌门(Actinobacteria)、蓝藻门(Cyanobacteria)和疣微菌门(Verrucomicrobia)在水体中的丰度较高,而γ变形杆菌纲(γ-Proteobacteria)、δ变形杆菌纲(δ-Proteobacteria)、绿弯菌门(Chloroflexi)、厚壁菌门(Firmicutes)和酸杆菌门(Acidobacteria)则在沉积物中有着更高丰度.好氧或兼性厌氧菌为主的水体类群和厌氧菌为主的沉积物类群体现出两者生境差异,沉积物中蕴含的病原菌存在二次释放到水体中的危险.研究结果为揭示高度人工化的、非常规补给水源补充下的和城市河道污染胁迫下的微生物群落变化机制提供科学依据.

关键词：微生物水体沉积物多样性群落结构 LEfSe组间差异

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Synthesis and Characterization of Two New Organically Templated Open-framework Uranium Phosphites

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1380-1386页

作者： XU Jian-Fu LI Hao-Hong CAO yan-Ning HUANG Chang-Cang ZHANG Han-Hui LIU dong-Sheng yanG Qi-Yu SUN Rui-Qing College of Chemistry and Chemical Engineering Fuzhoi University Fuzhou Fujian 350002 China Department of Chemistry Jinggangshan College Ji ＇an Jiangxi 343009 China

Two organically templated uranium phosphites, （C4H12N）（UO2）（HPO3）（NO3）（Mr = 486.16） 1 and （C16H36N）2（UO2）2（H2PO3）2（HPO3）（NO3）2 （Mr= 1390.95） 2, were prepared by evaporation from aqueous solution of uranyl nitrate, phosphite acid and their respective organic ammonium hydroxids. Their structures were determined by single-crystal X-ray diffraction and further characterized by infrared and fluorescence spectroscopy. In 1, pentagonal [UO7] bipyramids share comers with three [HPO3]2- tetrahedra and one edge with a [NO3]- anion to form [（UO2）- （HPO3）（NO3）]^- ladder-like chains parallel to the b axis. The structure of 2 is also based upon one-dimensional anionic [（UO2）2（H2PO3）2（HPO3）（NO3）2]2-chains of comer-sharing penta- gonal [UOT] bipyramids with [H2PO3]- and [HPO3] tetrahedra, which is still unknown in structural chemistry of uranium so far. Crystal data for 1： monoclinic, space group C2/m, a = 21.808（7）, b = 6.9605（15）, c = 8.357（2） A, β = 98.327（15）°, V= 1255.2（6） A^3, Z = 4, Dc = 2.573 g/cm^3, F（000） = 888, μ = 13.086 mm^-1 the final R = 0.0418 and wR = 0.0906 （I 〉 2σ（I））; and those for 2： monoclinic, space group C2/c, a = 36.4549（8）, b = 14.5296（11）, c = 20.8253（11） A, β = 101.7440（8）°, V= 10799.7（10） A3, Z = 8, Dc= 1.711 g/cm^3, F（000） = 5424,μ = 6.144 mm^-1, the final R= 0.0368 and wR= 0.0865 （I〉 2σ（I））.

关键词： uranium phosphite organically templated crystal structure fluorescence

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Strength and fatigue properties of three-step sintered dense nanocrystal hydroxyapatite bioceramics

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Frontiers of Materials Science 2013年第2期7卷 190-195页

作者： Wen-Guang guo Zhi-Ye QIU Han CUI Chang-Ming WANG Xiao-Jun ZHANG In-Seop LEE Yu-Qi dong Fu-Zhai CUI School of Materials Science and Engineering Tsinghua University Beijing 100084 China Beijing AIIgens Medical Science and Technology Co. Ltd. Beijing 100085 China Institute of Natural Science and Atomic-scale Surface Science Research Center Yonsei University Seoul 120-749 Korea Department of Orthopedics Renji Hospital Affiliated with Shanghai Jiao Tong University School of Medicine Shanghai 200127 China

Dense hydroxyapatite （HA） ceramic is a promising material for hard tissue repair due to its unique physical properties and biologic properties. However, the brittleness and low compressive strength of traditional HA ceramics limited their applications, because previous sintering methods produced HA ceramics with crystal sizes greater than nanometer range. In this study, nano-sized HA powder was employed to fabricate dense nanocrystal HA ceramic by high pressure molding, and followed by a three-step sintering process. The phase composition, microstructure, crystal dimension and crystal shape of the sintered ceramic were examined by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. Mechanical properties of the HA ceramic were tested, and cytocompatibility was evaluated. The phase of the sintered ceramic was pure HA, and the crystal size was about 200 nm. The compressive strength and elastic modulus of the HA ceramic were comparable to human cortical bone, especially the good fatigue strength overcame brittleness of traditional sintered HA ceramics. Cell attachment experiment also demonstrated that the ceramics had a good cytocompatibility.

关键词： nanocrystal hydroxyapatite ceramic three-step sintering mechanicalproperty fatigue strength cytocom patibility

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The Progenitors of Type Ia Supernovae with Asymptotic Giant Branch Donors

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Research in Astronomy and Astrophysics 2023年第7期23卷 118-125页

作者： Lu-Han Li dong-dong Liu Bo Wang Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China International Centre of Supernovae Yunnan Key LaboratoryKunming 650216China University of Chinese Academy of Sciences Beijing 100049China

TypeⅠa supernovae(SNe Ia)are among the most energetic events in the *** are excellent cosmological distance indicators due to the remarkable homogeneity of their light ***,the nature of the progenitors of SNeⅠa is still not well *** the single-degenerate model,a carbon-oxygen white dwarf(CO WD)could grow its mass by accreting material from an asymptotic giant branch(AGB)star,leading to the formation of SNe Ia when the mass of the WD approaches to the Chandrasekhar-mass limit,known as the AGB donor *** this channel,previous studies mainly concentrate on the wind-accretion pathway for the mass-increase of the *** the present work,we employed an integrated mass-transfer prescription for the semidetached WD+AGB systems,and evolved a number of WD+AGB systems for the formation of SNe Ia through the Roche-lobe overflow process or the wind-accretion *** provided the initial and final parameter spaces of WD+AGB systems for producing SNe *** also obtained the density distribution of circumstellar matter at the moment when the WD mass reaches the Chandrasekhar-mass ***,we found that the massive WD+AGB sample AT 2019qyl can be covered by the final parameter space for producing SNe Ia,indicating that AT 2019qyl is a strong progenitor candidate of SNe Ia with AGB donors.

关键词： stars:evolution (stars:)supernovae:general (stars:)binaries(including multiple):close (stars:)white dwarfs

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Insight into the Ebola virus nucleocapsid assembly mechanism： crystal structure of Ebola virus nucleoprotein core domain at 1.8 A resolution

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Protein & Cell 2015年第5期6卷 351-362页

作者： Shishang dong Peng yang guobang Li Baocheng Liu Wenming Wang Xiang Liu Boran Xia Cheng yang Zhiyong Lou Yu guo Zihe Rao State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy Nankai University Tianjin 300071 China College of Life Sciences Nankai University Tianjin 300071 China Tianjin International Joint Academy of Biotechnology & Medicine Tianjin 300457 China

Ebola virus （EBOV） is a key member of Filoviridae family and causes severe human infectious diseases with high morbidity and mortality. As a typical negative-sense single-stranded RNA （-ssRNA） viruses, EBOV possess a nucleocapsid protein （NP） to facilitate genomic RNA encapsidation to form viral ribonucleoprotein complex （RNP） together with genome RNA and polymerase, which plays the most essential role in virus proliferation cycle. However, the mechanism of EBOV RNP formation remains unclear. In this work, we solved the high resolution structure of core domain of EBOV NP. The polypeptide of EBOV NP core domain （NPcore） pos- sesses an N-lobe and C-lobe to clamp a RNA binding groove, presenting similarities with the structures of the other reported viral NPs encoded by the members from Mononegavirales order. Most strikingly, a hydrophobic pocket at the surface of the C-lobe is occupied by an a- helix of EBOV NPcore itself, which is highly conserved among filoviridae family. Combined with other bio- chemical and biophysical evidences, our results provides great potential for understanding the mechanism underlying EBOV RNP formation via the mobility of EBOV NP element and enables the development of antiviral therapies targeting EBOV RNP formation.

关键词： Filoviridae Ebola virus nucleoprotein nucleocapsid crystal structure assembly mechanism

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High-Performance and Hysteresis-Free Perovskite Solar Cells Based on Rare-Earth-Doped SnO_(2) Mesoporous Scaffold

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Research 2019年第1期2019卷 378-390页

作者： Qiyao guo Jihuai Wu Yuqian yang Xuping Liu Zhang Lan Jianming Lin Miaoliang Huang Yuelin Wei Jia dong Jinbiao Jia Yunfang Huang Engineering Research Center of Environment-Friendly Functional Materials Ministry of EducationInstitute of Materials Physical ChemistryHuaqiao UniversityXiamen 361021China School of Physics and Physical Engineering Qufu Normal UniversityQufu 273165China School of Chemical Engineering Huaqiao UniversityXiamen 361021China

Tin oxide(SnO_(2)),as electron transport material to substitute titanium oxide(TiO_(2))in perovskite solar cells(PSCs),has aroused wide ***,the performance of the PSCs based on SnO_(2) is still hard to compete with the TiO_(2)-based ***,a novel strategy is designed to enhance the photovoltaic performance and long-term stability of PSCs by integrating rare-earth ions Ln^(3+)(Sc^(3+),Y^(3+),La^(3+))with SnO_(2) nanospheres as mesoporous *** doping of Ln promotes the formation of dense and large-sized perovskite crystals,which facilitate interfacial contact of electron transport layer/perovskite layer and improve charge transport *** dopant optimizes the energy level of perovskite layer,reduces the charge transport resistance,and mitigates the trap state *** a result,the optimized mesoporous PSC achieves a champion power conversion efficiency(PCE)of 20.63%without hysteresis,while the undoped PSC obtains an efficiency of 19.01%.The investigation demonstrates that the rare-earth doping is low-cost and effective method to improve the photovoltaic performance of SnO_(2)-based PSCs.

关键词： density. perovskite doping

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LncRNA NPTN-IT1-201 Ameliorates Depressive-like Behavior by Targeting miR-142-5p and Regulating Inflammation and Apoptosis via BDNF

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Current Medical Science 2024年第5期44卷 971-986页

作者： Jun HE Peng XIE Xiao-qiong AN dong-fen guo Bin BI Gang WU Wen-feng YU Zhen-kui REN Li ZUO Department of Immunology School of Basic Medical ScienceGuizhou Medical UniversityGuiyang550004China Department of Laboratory Medicine The Second People’s Hospital of Guizhou ProvinceGuiyang550004China Guizhou Provincial Center for Clinical Laboratory Guiyang550002China Key Laboratory of Endemic and Ethnic Diseases Ministry of EducationSchool of Basic Medical ScienceGuizhou Medical UniversityGuiyang550004China Psychosomatic Department The Second People’s Hospital of Guizhou ProvinceGuiyang550004China

Objective Long noncoding RNAs(lncRNAs)and microRNAs(miRNAs)are widely expressed in the brain and are associated with the development of neurological and neurodegenerative ***,their roles and molecular mechanisms in major depressive disorder(MDD)remain largely *** study aimed to identify lncRNAs and miRNAs involved in the development of MDD and elucidate their molecular *** Transcriptome and bioinformatic analyses were performed to identify miRNAs and lncRNAs related to MDD.C57 mice were subjected to chronic unpredictable mild stress(CUMS)to establish a depression *** containing either lncRNA NPTN-IT1-201 or miR-142-5p were microinjected into the hippocampal region of these *** tests including the sucrose preference test(SPT),tail suspension test(TST),and forced swim test(FST)were conducted to evaluate depressive-like *** The results revealed that overexpression of lncRNA NPTN-IT1-201 or inhibition of miR-142-5p significantly ameliorated depressive-like behaviors in CUMS-treated ***-luciferase reporter assays confirmed interactions between miR-142-5p with both brain-derived neurotrophic factor(BDNF)and *** analysis revealed significant alterations in relevant biomarkers in the blood samples of MDD patients compared to healthy *** analyses,including HE and Nissl staining,showed marked structural changes in brain tissues following CUMS treatment,which were partially reversed by lncRNA NPTN-IT1-201 overexpression or miR-142-5p *** imaging demonstrated significant differences in the levels of BAX,Bcl2,p65,Iba1 among different treatment *** assays confirmed reduced apoptosis in brain tissues following these *** blotting showed the significant differences in BDNF,BAX,and Bcl2 protein levels among different treatment *** NPTN-IT1-201 regulates inflammation and apoptosis in MDD by targeting BDN

关键词： depressive-like behavior chronic unpredictable mild stress long noncoding RNA microRNA brain-derived neurotrophic factor

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An Effective On-line Surface Particles Inspection Instrument for Large Aperture Optical Element

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International Journal of Automation and computing 2017年第4期14卷 420-431页

作者： Wen-dong Ding Zheng-Tao Zhang Da-Peng Zhang De Xu Hai-Bing Lv Xin-Xiang Miao guo-Rui Zhou Hao Liu Research Center of Precision Sensing and Control Institute of Automation Chinese Academy of Sciences School of Computer and Control Engineering University of Chinese Academy of Sciences Laser Fusion Research Center China Academy of Engineering Physics

Surface particles growing in large aperture optical element （LAOE） have significant impact on LAOE＇s stable operation. It is a challenge for the online system to inspect the particles with long working distance, enough precision and high efficiency because of the system constraints. In this paper, an effective and portable inspection instrument is designed based on dark-field imaging principle. A Nikon lens and an industrial high definition （HD） camera are selected to construct the vision system to inspect particles of microns size spreading over hundreds of millimeters. Using two motors and other mechanical structure, the system can realize auto-focus and image rectification functions. The line light sources are installed on both sides of the LAOE in a sealed box while the vision system is portable and working outside the box. An adaptive binarization method is proposed to process the captured dark-field image. The distribution of particles on the LAOE＇s surface is investigated. Because of the high resolution of the captured image, the SSE2 instructions optimization method is used to reduce the time cost of the algorithm. Experiments show that the instrument can inspect LAOE effectively and accurately.

关键词： Dark-field imaging image rectification adaptive binarization particle inspection large aperture optical elements(LAOE).

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