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Concerted Steric and Electronic Strategy in Thermostable Salicylaldiminato Nickel Catalysts for Ethylene(Co)polymerization

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Chinese Journal of Polymer Science 2024年第8期42卷 1085-1092页

作者： Hong-yu Ji Hong-Liang Mu Chun-Feng Tang yu-Xing Zhang yue Chi Zhong-Bao Jian Key Laboratory of Advanced Structural Materials Ministry of EducationSchool of Materials Science and EngineeringChangchun University of TechnologyChangchun 130012China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Olefin polymerization is one of the most im portant chemical reactions in *** work presents a strategy that emphasizes the synergistic meta/poro-steric hindrance of N-aryl groups and electronic effects in newly synthesized neutral salicylaldiminato nickel *** nickel(Ⅱ)catalysts exhibit exceptional thermostability,ranging from 30℃to 130℃,demonstrating enhanced catalytic activities and broadly regulated polyethylene molecular weights(3-341 kg·mol^(-1))and controlled polymer branch density(2-102 brs/1000C).The preferred catalyst Ni3 with concerted steric and electronic effects enables the production of solid-state semi-crystalline polyethylene materials at temperatures below 90℃.Notably,Ni3 exhibits an impressive tolerance of 110℃and can withstand even the challenging polymerization temperature of 130℃,leading to the production of polyethylene wax and ***,functionalized polyethylene is produced.

关键词： Polyolefin Salicylaldiminato ligand Nickel catalyst Oil Wax

Microdeletion on Xq27.1 in a Chinese VACTERL-Like Family with Kidney and Anal Anomalies

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Biomedical and Environmental Sciences 2024年第5期37卷 503-510页

作者： LI Min ZHANG yu Lan ZHANG Kai Li LI Ping Ping Lyu yu Han LIANG Ya Xin yu yue Department of Gynecology and Obstetrics Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China Chinese Academy of Medical Sciences and Peking Union Medical College Beijing HospitalBeijing 100730China The Key Laboratory of Geriatrics Beijing Institute of GeriatricsBeijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China

Objective VATER/VACTERL-like association is associated with adverse pregnancy *** evidence of this disorder is *** this study,we aimed to provide genetic insights to improve the diagnosis of *** We have described a Chinese family in which four members were affected by renal defects or agenesis,anal atresia,and anovaginal fistula,which is consistent with the diagnosis of a VACTERL-like *** and genetic analyses were conducted using genome and exome *** Segregation analysis revealed the presence of a recessive X-linked microdeletion in two living affected individuals,harboring a 196–380 kb microdeletion on Xq27.1,which was identified by familial exome *** sequencing was performed on the affected male,confirming a-196 kb microdeletion in Xq27.1,which included a 28%loss of the CDR-1 *** family members were included in the co-segregation analysis,and only VACTERL-like cases with microdeletions were reported in *** These results suggest that the 196–380 kb microdeletion in Xq27.1 could be a possible cause of the VATER/VACTERL-like ***,further genetic and functional analyses are required to confirm or rule out genetic background as the definitive cause of the VACTERL association.

关键词： Prenatal diagnosis VACTERL whole-genome sequencing whole-exome sequencing X-linked

Nanodiamond:a promising metal-free nanoscale material in photocatalysis and electrocatalysis

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Rare Metals 2024年第8期43卷 3501-3552页

作者： Xiao-Wu Gao zi-Wei Zhao Yang He Sai-Fei Fan Ke-Ran Jiao Si-yu Lou Xin-yue Han Peng-Fei Song Rong Cai Zhun Hu Zhong-Jie Jiang Yong-Jie Wang Jia-Qi Zhu Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems School of ScienceHarbin Institute of TechnologyShenzhen 518055China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080China School of Advanced Technology Xi'an Jiaotong-Liverpool UniversitySuzhou215000China Department of Biosciences Rice UniversityHoustonTX 77251USA Institute of Industrial Catalysis School of Chemical Engineering and TechnologyXi'an Jiaotong UniversityXi'an 710049China Guangzhou Key Laboratory for Surface Chemistry of Energy Materials New Energy Research Institute&Guangdong Engineering and Technology Research Center for Surface Chemistry of Energy MaterialsCollege of Environment and EnergySouth China University of TechnologyGuangzhou 510006China

Benefiting from its surface-rich functional groups,eco-friendliness,impressive electrochemical properties,excellent light absorption,structural tunability at the atomic/morphological level,and ultra-high stability under harsh conditions,nanodiamond has emerged as a promising carbon-based non-metallic material in the field of energy conversion such as electrocatalysis and ***,nanodiamond,as a new generation of green catalysts,can overcome the poisoning of catalysts by complex pollutants in advanced oxidation processes,thus effectively removing organic matter from water,which is unparalleled in reducing the cost of water purification and avoiding secondary cross-contamination of water by traditional heavy metal-based ***,we review the research and development of nanodiamonds as major electrocatalysts and photocatalysts for energy conversion and for air/water treatment for environmental *** relevant properties,trimming strategy,mechanistic understanding,and design principles of nanodiamond as a catalyst are described,as well as the challenges and prospects of this emerging field.

关键词： Carbon materials Nanodiamond Electrocatalysis Photocatalysis Energy conversion Pollutant treatment

Highly Red Emissive Conjugated Homopolymers Based on Double B←N Bridged Bipyridine Unit

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Chinese Journal of Polymer Science 2024年第8期42卷 1029-1037页

作者： yu-yue Gao Kai-yuan Zhang Shu-Meng Wang Hui Tong Jun Liu State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Conjugated homopolymers based on six-member rings,e.g.,polyfluorene,always exhibit blue emission and conjugated homopolymers based on five-member rings,e.g.,polythiophene,can give red emission with low *** this work,we report a series of new conjugated homopolymers based on six-member rings with high-efficiency deep-red *** repeating units of the red light emitting homopolymers are double B←N bridged bipyridine(BNBP)with the boron atoms functionalized with diphenyl,borafluorene,and 2,7-di-tert-butyl-borafluorene groups,*** relationship between the chemical structures and the opto-electronic properties of the monomers and the homopolymers has been systematically *** three polymers emit pure red light(λ_(max)=656 nm)or deep red light(λ_(max)=693 nm)with fluorescence quantum efficiency in solution higher than 60%.The polymers can be used as the emitters in solution-processed organic light-emitting diodes with red emission and decent device *** work indicates a new strategy to design highly efficient light emitting conjugated polymers.

关键词： Conjugated homopolymers Double B←N bridged bipyridine(BNBP) Deep-red emission High fluorescent efficiency

Simulation study of the performance of the Very Large Area gamma-ray Space Telescope

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Nuclear Science and Techniques 2024年第9期35卷 1-17页

作者： Xu Pan Wei Jiang Chuan yue Shi-Jun Lei yu-Xin Cui Qiang yuan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

The Very Large Area gamma-ray Space Telescope(VLAST)is a mission concept proposed to detect gamma-ray photons through both Compton scattering and electron–positron pair production mechanisms,thus enabling the detection of photons with energies ranging from MeV to *** project aims to conduct a comprehensive survey of the gamma-ray sky from a low-Earth orbit using an anti-coincidence detector,a tracker detector that also serves as a low-energy calorimeter,and a high-energy imaging *** developed a Monte Carlo simulation application of the detector using the GEANT4 toolkit to evaluate the instrument performance,including the effective area,angular resolution,and energy resolution,and explored specific optimizations of the detector *** simulation-based analysis indicates that the current design of the VLAST is physically feasible,with an acceptance above 10 m^(2)sr which is four times larger than that of the Fermi-LAT,an energy resolution better than 2%at 10 GeV,and an angular resolution better than 0.2◦at 10 *** VLAST project promises to make significant contributions to the field of gamma-ray astronomy and enhance our understanding of the cosmos.

关键词： Space astronomy Gamma-ray telescope Calorimeter Monte Carlo simulation

Three-Dimensional Density Distribution and Seismic Activity along the Guxiang–Tongmai Segment of the Jiali Fault,Tibet

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 454-467页

作者： FAN Pengxiao yu Changqing WANG Ruixue ZENG Xiangzhi QU Chen ZHANG yue Institute of Land and Resources Engineering Kunming University of Science and Technology Kunming 650000China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Jiangsu Donghai Continental Deep Hole Crustal Activity National Observation and Research StationLianyungangJiangsu 222000China

The Guxiang-Tongmai segment of the Jiali fault is situated northeast of the Namche Barwa Syntaxis in northeastern *** is one of the most active strike-slip faults near the syntaxis and plays a pivotal role in the examination of seismic activity within the eastern Himalayan *** study in the research region has yielded a 1:200000 gravity dataset covering an area 1500 km^(2).Using wavelet transform multiscale decomposition,scratch analysis techniques,and 3D gravity inversion methods,gravity anomalies,fault distributions,and density structures were determined across various *** the integration of our new gravity data with other geophysical and geological information,our findings demonstrate substantial variations in the overall crustal density within the region,with the fault distribution closely linked to these density *** in stratigraphic density are important causes of variations in the capacity of geological formations to endure regional tectonic *** are predominantly concentrated within the density transition zone and are primarily situated in regions of elevated *** hanging wall stress within the Guxiang-Tongmai segment of the Jiali fault exhibits a notable concentration,marked by pronounced anisotropy,and is positioned within the density differential zone,which is prone to earthquakes.

关键词： seismicity deep-density structure wavelet transform multi-scale decomposition scratch analysis 3D gravity inversion Jiali fault Tibet

Modified filter for mean elements estimation with state jumping

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Journal of Systems Engineering and Electronics 2024年第4期35卷 999-1012页

作者： yu Yanjun yue Chengfei LI Huayi WU yunhua CHEN Xueqin Research Center of Satellite Technology Harbin Institute of TechnologyHarbin 150001China Institute of Space Science and Applied Technology Harbin Institute of Technology(Shenzhen)Shenzhen 518055China College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 211106China

To investigate the real-time mean orbital elements(MOEs)estimation problem under the influence of state jumping caused by non-fatal spacecraft collision or protective orbit trans-fer,a modified augmented square-root unscented Kalman filter(MASUKF)is *** MASUKF is composed of sigma points calculation,time update,modified state jumping detec-tion,and measurement *** with the filters used in the existing literature on MOEs estimation,it has three main ***,the state vector is augmented from six to nine by the added thrust acceleration terms,which makes the fil-ter additionally give the state-jumping-thrust-acceleration ***,the normalized innovation is used for state jumping detection to set detection threshold concisely and make the filter detect various state jumping with low ***,when sate jumping is detected,the covariance matrix inflation will be done,and then an extra time update process will be con-ducted at this time instance before measurement *** this way,the relatively large estimation error at the detection moment can significantly ***,typical simulations are per-formed to illustrated the effectiveness of the method.

关键词： unscented Kalman filter mean orbital elements(MOEs)estimation state jumping detection nonlinear system

Stress corrosion cracking behavior of buried oil and gas pipeline steel under the coexistence of magnetic field and sulfate-reducing bacteria

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Petroleum Science 2024年第2期21卷 1320-1332页

作者： Jian-yu He Fei Xie Dan Wang Guang-Xin Liu Ming Wu yue Qin College of Petroleum Engineering Liaoning Petrochemical UniversityFushun113001LiaoningChina Key Laboratory of Oil and Gas Storage and Transportation Technology in Liaoning Province Fushun113001LiaoningChina State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China PipeChina West East Gas Pipeline Company Shanghai200120China

Magnetic field and microorganisms are important factors influencing the stress corrosion cracking(SCC)of buried oil and gas pipelines. Once SCC occurs in buried pipelines, it will cause serious hazards to the soil environment. The SCC behavior of X80 pipeline steel under the magnetic field and sulfate-reducing bacteria(SRB) environment was investigated by immersion tests, electrochemical tests, and slow strain rate tensile(SSRT) tests. The results showed that the corrosion and SCC sensitivity of X80 steel decreased with increasing the magnetic field strength in the sterile environment. The SCC sensitivity was higher in the biotic environment inoculated with SRB, but it also decreased with increasing magnetic field strength, which was due to the magnetic field reduces microbial activity and promotes the formation of dense film layer. This work provided theoretical guidance on the prevention of SCC in pipeline steel under magnetic field and SRB coexistence.

关键词： Magnetic field Sulfate-reducing bacteria Film layer Stress corrosion cracking Oil and gas pipelines

Accuracy evaluation for in-situ machining reference points binocular measurement based on credibility probability

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Chinese Journal of Aeronautics 2024年第1期37卷 472-486页

作者： Binchao yu Wei LIU Yanze ZHANG Dazhi MA Zhenyuan JIA Yi yue Jiabo ZHANG Key Laboratory for Precision and Non-Traditional Machining Technology of the Ministry of Education Dalian University of TechnologyDalian 116024China Beijing Spacecrafts China Academy of Space TechnologyBeijing 100081China

Passive binocular measurement systems are being increasingly utilized in the in-situ industries of automobiles,aviation,and aerospace,*** to their excellent qualities of accuracy,efficiency,and cost *** the barrier of evaluating the accuracy of measured objects resulted from the unequal equivalent focal length and quantization of pixels,has limited their further development and application of high requirements for in-situ machining,e.g.,the measurement of machining reference points for the positioning of robotic drilling in aerospace *** this paper,an accuracy evaluation method is proposed to address the ***,the unequal equivalent focal length is considered to improve the accuracy of 3D ***,the credibility probability model is developed to calculate the probability of the observed error in the public view of the binocular measurement system and indicates the direction of ***,the in-situ experiment is carried out to validate the method within the effective public view range of 300 mm×300 *** experiment results show that the RMSs of observed errors are superior to 0.035 mm,and the credibility probabilities are all higher than 0.91;the maximum 3D reconstruction accuracy improvement is 60.3%,with the error reduced from 0.078 mm to 0.031 mm.

关键词： Aerospace manufacturing Binocular vision Credibility probability Pixel quantization Unequal equivalent focal length