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A Deprojection Analysis of Abell 1650 with XMM-Newton

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Chinese Journal of Astronomy and Astrophysics 2006年第2期6卷 181-196页

作者： shu-mei jia Yong Chen Li Chen Department of Astronomy Beijing Normal University Beijing 100875 Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academyof Sciences Beijing 100049

We revisit the XMM-Newton observation of the galaxy cluster Abell 1650 with a deprojection technique. We find that the radial deprojected spectra of Abell 1650 can be marginally fitted by a single-temperature model. In order to study the properties of the central gas, we fit the spectra of the central two regions with a two- temperature model. The fits then become significantly better and the cool gas about 1～2 keV can be connected with the gas cooling. Fitting the central spectrum （r≤1′） by using a cooling flow model with an isothermal component yields a small mass deposition rate of 10-7^＋11 M. yr^-1, while the standard cooling flow model can not fit this spectrum satisfactorily except that there exists a cut-off temperature having a level of about 3 keV. From the isothermal model we derive the deprojected electron density profile ne（r）, and then together with the deprojected temperature profile the total mass and gas mass fraction of cluster are also determined. We compare the properties of Abell 1650 with those of Abell 1835 （a large cooling flow cluster） and some other clusters, to explore the difference in properties between large and small cooling flow cluster, and what causes the difference in the cooling flow of different clusters. It has been shown that Abell 1835 has a steeper potential well and thus a higher electron density and a lower temperature in its center, indicating that the shape of the gravitational potential well in central region determines the cooling flow rates of clusters. We calculate the potential, internal and radiated energies of these two clusters, and find that the gas energies in both clusters are conserved during the collapsing stage.

关键词： galaxies: clusters: individual: Abell 1650 -galaxies: cooling flowsgalaxies: evolution - galaxies: intergalactic medium - X-rays: galaxies: clusters

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基于教师专业发展的乡村学校管理现代化

教育教学论坛 2024年第35期 41-44页

作者：舒佳楣曾慧何敦培衡阳师范学院教育科学学院湖南衡阳421002

乡村教师专业发展离不开学校管理现代化。乡村学校管理现代化是国家战略的必然要求和乡村学校的内在要求,是教育现代化和教育治理的重要内容,对乡村教师高质量发展和乡村学校管理改革具有关键作用。乡村学校管理现代化是管理理念、管理... 详细信息

乡村教师专业发展离不开学校管理现代化。乡村学校管理现代化是国家战略的必然要求和乡村学校的内在要求,是教育现代化和教育治理的重要内容,对乡村教师高质量发展和乡村学校管理改革具有关键作用。乡村学校管理现代化是管理理念、管理组织、管理手段、管理队伍、管理方法五个方面相结合的、系统的、科学的现代化。为促进乡村教师专业发展,乡村学校管理现代化须坚持问题导向、树立系统观念、扎根本土文化、恪守教师为本、强化数字管理、改进考核评价。

关键词：教师专业发展乡村学校管理现代化

High-rate lithium-ion battery performance of a ternary sea urchin-shaped CoNiO_(2)@NiP_(6)Mo_(18)/CNTs composites

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Journal of Energy Chemistry 2024年第9期96卷 516-525页

作者： Li-ping Cui shuang Sun Kai Yu shu Zhang mei-lin Wang jia-jia Chen Bai-bin Zhou Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringHarbin Normal UniversityHarbin 150025HeilongjiangChina State Key Laboratory of Physical Chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical EngineeringCollaborative Innovation Centre of Chemistry for Energy MaterialsXiamen UniversityXiamen 361005FujianChina

Bimetallic oxides are attractive anode materials for lithium-ion batteries(LIBs)due to their large theoretical ***,the low conductivity,short cycle life,and poor rate capability are the bottlenecks for their further *** overcome above issues,the basket-like polymolybdate(NiP_(6)Mo_(18))and carbon nanotubes(CNTs)were uniformly embedded on the urchin-shaped CoNiO_(2)nanospheres to yield a ternary composites CoNiO_(2)@NiP_(6)Mo_(18)/CNTs via electrostatic *** multi-level morphology of urchin spinules accelerates the diffusion rate of Li^(+);CNT improves the conductivity and enhances cycle stability of the material;and heteropoly acid contributes more redox activity ***,CoNiO_(2)@NiP_(6)Mo_(18)/CNTs as an anode of LIBs exhibits a high initial capacity(1396.7 mA h g^(−1)at 0.1 A g^(−1)),long-term cycling stability(750.2 mA h g^(−1)after 300 cycles),and rate performance(450.3 mA h g^(−1)at 2 A g^(−1)),which are superior to reported metallic oxides anode of *** density functional theory(DFT)and kinetic mechanism suggest that CoNiO_(2)@NiP_(6)Mo_(18)/CNTs delivers an outstanding pseudocapacitance and rapid Li^(+)diffusion behaviors,which is due to the rich surface area of the urchin-like CoNiO_(2)with the uniform embeddedness of NiP_(6)Mo_(18)and *** study provides a new idea for optimizing the performance of bimetallic oxides and developing high-rate lithium-ion battery composites.

关键词： Bi-metal oxides Transition metal oxides Polyoxometalates Nanocomposite LIBs

Exosome-Transmitted miR-224-5p Promotes Colorectal Cancer Cell Proliferation via Targeting ULK2 in p53-Dependent Manner

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Biomedical and Environmental Sciences 2024年第1期37卷 71-84页

作者： YANG Le mei ZHENG Qi LIU Xiao jia LI Xian Xian Veronica Lim CHEN Qi ZHAO Zhong Hua WANG shu Yang Department of Pathology School of Basic MedicineFudan UniversityShanghai 200032China Department of Pathology Dunedin School of MedicineUniversity of OtagoDunedin 9054New Zealand Department of Pathology Huashan HospitalFudan UniversityShanghai 200040China Shanghai Cancer Institute Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Teladoc Health Inc Shanghai 200335China Shanghai Medical College Fudan UniversityShanghai 200032China Shanghai Key Laboratory of Medical Imaging Computing and Computer Assisted Intervention Shanghai 200032China

Objective To investigate the role and molecular mechanism of exosomal miR-224-5p in colorectal cancer(CRC).Methods The miR-224-5p expression in CRC patient tissues and cell-derived exosomes was measured by laser capture microdissection and qRT-PCR,***-luciferase reporter gene assay was used to determine the target gene of *** protein expressions of p53 and unc-51 like kinase 2(ULK2)in CRC cells were detected by western *** cytometry was used to detect cell cycle and *** proliferation was measured by CCK8 and EdU *** The miR-224-5p expression was upregulated in CRC tissues and increased progressively with the rise of CRC *** cells secreted extracellular miR-224-5p mainly in an exosome-dependent manner,and then miR-224-5p could be transferred to surrounding tumor cells to regulate cell proliferation in the form of autocrine or ***,ULK2 was characterized as a direct target of miR-224-5p and was downregulated in CRC ***,ULK2 inhibited CRC cell proliferation in a p53-dependent ***,exosome-derived miR-224-5p partially reversed the proliferation regulation of ULK2 on CRC *** Our findings demonstrate that exosome-transmitted miR-224-5p promotes p53-dependent cell proliferation by targeting ULK2 in CRC,which may offer promising targets for CRC prevention and therapy.

关键词： miR-224-5p Exosome ULK2 p53 Cell proliferation Colorectal cancer

Progress in preparation of AlN-reinforced magnesium matrix composites:A review

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China Foundry 2024年第1期21卷 1-10页

作者： Lu Chen shu-lin Lü Di-jia Zhao Wei Guo jian-yu Li shu-sen Wu State Key Lab of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

As a ceramic material,AlN has very good thermophysical and mechanical *** addition,AlN is an effective refining agent for Mg alloys because it has a lattice constant similar to that of ***,AlN is an ideal reinforcement for magnesium matrix composites(MMCs),and is attracting increasing *** review addresses the development of preparation technologies for AlN-reinforced Mg matrix *** mainstream preparation techniques include stir casting,melt infiltration,powder metallurgy,and in-situ *** addition,the advantages and disadvantages of these techniques are analyzed in depth,and it is pointed out that the next direction for the preparation of high-performance AlN-reinforced MMCs is less aluminization and multiple technologies integration.

关键词： AlN MMCs preparation thermophysical property mechanical property

A condition-based maintenance policy for reconfigurable multi-device systems

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Advances in Manufacturing 2024年第2期12卷 252-269页

作者： shu-Lian Xie Feng Xue Wei-Min Zhang jia-Wei Zhu School of Mechanical Engineering Tongji UniversityShanghai201804People’s Republic of China

The exploration of component states for optimizing maintenance schedules in complex systems has garnered significant interest from ***,current literature usually overlooks the critical aspects of system flexibility and *** implementation of system reconfiguration can effectively mitigate system downtime and enhance production *** study proposes a dynamic condition-based maintenance policy considering reconfiguration for reconfigurable systems.A double-layer decision rule was constructed for the devices and *** achieve the best overall maintenance effect of the system,the remaining useful life probability distribution and recommended maintenance time of each device were used to optimize the concurrent maintenance time window of the devices and determine whether to reconfigure them.A comprehensive maintenance efficiency index was introduced that simultaneously considered the maintenance cost rate,reliability,and availability of the system to characterize the overall maintenance *** reconfiguration cost was included in the maintenance *** proposed policy was tested through numerical experiments and compared with different-level *** results show that the proposed policy can significantly reduce the downtime and maintenance costs and improve the overall system reliability and availability.

关键词： Condition-based maintenance(CBM) Reconfigurable system Remaining useful life Maintenance cost System reliability

Diagnosis and treatment of biliary mucinous cystic neoplasms: A single-center experience

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 495-501页

作者： Jun-Jun jia Ya-Fen Cheng mei-Bao Feng Li Liu Ming-Qi shuai Xiao-Dong Shen Xiao-Feng Tang shu-Sen Zheng Division of Hepatobiliary and Pancreatic Surgery Department of Surgerythe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of International Healthcare Center the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Pathology the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Library the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Background: Biliary mucinous cystic neoplasms(BMCNs) are rare hepatobiliary cystic tumors, which can be divided into noninvasive and invasive types. This study aimed to investigate the diagnosis, treatment, and prognosis of BMCNs in a large single center. Methods: We analyzed 49 patients with BMCNs confirmed by postoperative pathology at the First Afflliated Hospital, Zhejiang University School of Medicine between January 2007 and December 2021. Results: Among the 49 patients, 37 were female(75.5%), and the average age was 57.04 years. Common symptoms included abdominal discomfort, jaundice and fever, while 22 patients(44.9%) had no symptoms. Serum carbohydrate antigen(CA) 19-9 and CA125 concentrations were elevated in 34.8% and 19.6% of patients, respectively. Forty-eight patients had tumors in the intrahepatic bile ducts and only one had a tumor in the extrahepatic bile duct. Forty-eight patients with noninvasive intrahepatic BMCNs were further analyzed in terms of pathological features: 34(70.8%) had low-grade intraepithelial neoplasms(LGINs), and 14(29.2%) had high-grade intraepithelial neoplasms(HGINs). The potential immunohistochemical markers of BMCNs were cytokeratin(CK) 19, CK7, estrogen receptor and progesterone receptor. Follow-up data for 37 patients with intrahepatic BMCNs were obtained. The median overall survival(OS) of BMCNs was not reached. The longest survival time was 137 *** 5-and 10-year OS rates were 100% and 85.4%, respectively. The 5-and 10-year recurrence-free survival(RFS) rates were 93.9% and 80.2%, respectively. Conclusions: BMCNs are rare cystic neoplasms that commonly occur in middle-aged females. BMCNs can only be diagnosed and classified by postoperative pathology, as there are no specific clinical presentations, serological indicators or imaging modalities for preoperative diagnosis. Complete surgical resection is necessary for BMCNs, and the postoperative prognosis is favorable.

关键词： Biliary mucinous cystic neoplasms Low-grade intraepithelial neoplasms High-grade intraepithelial neoplasms Overall survival Recurrence-free survival

Enhanced preparation of dendritic metallic vanadium in recyclable NaCl-KCl-VCl_(2) molten salt by V_(2)CO electrolysis

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Rare Metals 2024年第8期43卷 3961-3973页

作者： jia-Liang An Ming-Yong Wang Yong-Zheng jia Jin-Tao Zhang Bao-Yan Feng shu-Qiang jiao State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China College of Material Science and Engineering Hebei Province Laboratory of Inorganic Nonmetallic MaterialsNorth China University of Science and TechnologyTangshan 063210China

A promising method for the preparation of pure metallic vanadium via V_(2)CO anode electrolysis was proposed and *** simple and controllable synthesis of a molten chloride salt containing VCl_(2) by an insitu reaction between VCl_(3) and metallic vanadium was verified through thermodynamic analysis and ***-KCl-VCl_(2) molten salt exhibited excellent recycling performance and could be repetitively used to prepare metallic vanadium by V_(2)CO *** V^(2+) ions remained in the molten salt after *** electrolysis conditions,such as the cathode diameter,current density,V^(2+) ion concentration,and temperature,were optimised to maximise the current *** was also simulated to reveal the regulatory *** highest current efficiency was 85%.The purity of metallic vanadium was up to 99.8%.In this study,an easy and efficient preparation of pure metallic vanadium was achieved.

关键词： V_(2)CO Metallic vanadium Current efficiency Molten salt electrolysis

Progress in the research on organic piezoelectric catalysts for dye decomposition

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 245-260页

作者： Zhaoning Yang Xiaoxin shu Di Guo Jing Wang Hui Bian Yanmin jia School of Science Xi’an University of Posts and TelecommunicationsXi’an 710121China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China

Organic contaminants have posed a direct and substantial risk to human wellness and the *** recent years,piezo-electric catalysis has evolved as a novel and effective method for decomposing these *** piezoelectric materials offer a wide range of options,most related studies thus far have focused on inorganic materials and have paid little attention to organic *** materials have advantages,such as being lightweight,inexpensive,and easy to process,over inorganic ***,this paper provides a comprehensive review of the progress made in the research on piezoelectric catalysis using organic materials,high-lighting their catalytic efficiency in addressing various *** addition,the applications of organic materials in piezoelectric cata-lysis for water decomposition to produce hydrogen,disinfect bacteria,treat tumors,and reduce carbon dioxide are ***,fu-ture developmental trends regarding the piezoelectric catalytic potential of organic materials are explored.

关键词： piezoelectric catalysis piezoelectric material dye decomposition organic materials