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Regularities of formation.of ternary alloy phases between non-transition metals

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Science China(Technological Sciences) 2000年第2期43卷 199-205页

作者：姚莉秀陈瑞亮钦佩陈念贻陆文聪 Shanghai Institute of Metallurgy Chinese Academy of Sciences Shanghai China Department of Chemistry Shanghai University Shanghai China

Using a four-parameter model based on extended Miedema’ s cellular model of alloy phases and pattern recognition methods, the regularities of formation.of ternary intermetallic compounds between non-transition metals have been investigated. The criterion of formation.can be expressed as some empirical functions of Φ (electronegativity), nws1/3( valence electron density in Wagn-er-Seitz cell), R (Pauling’s metallic radius) and Z (number of valence electrons in atom).

关键词： non-transition metals ternary intermetallic compounds regularities of formation.

In situ formation.of nanometer-scale TiO_2/SiC functional compositional film on carbon fiber

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Science China(Technological Sciences) 2005年第1期48卷 53-60页

作者： ZHOU Chunhua YIN Yansheng ZHANG Shuxiang LIU Wei College of Chemistry Chemical Engineering Jinan University Jinan 250022 China College of Material Science and Technologe Ocean University of China Qingdao 266003 China College of Chemistry Chemical Engineering Jinan University Jinan 250022 China College of Material Science and Technologe Ocean University of China Qingdao 266003 China College of Material Science and Technologe Ocean University of China Qingdao 266003 China

In the toluene solution of the precursor Polycarbosilane (PCS) containing low- molecular-mass additive Ti(OC4H9)4, TiO2/SiC nanometer-scale functional compositional film with the surface TiO2 layer on CF was formed in situ by means of polymer-derived precursors. The effects of Ti (OC4H9)4 concentrations and the maturating time were studied on the densification and TiO2 particle size of surface layer. The compositions of film were TiO2 and SiC crystal by XRD. According to the results of ESCA analysis, Ti(OC4H9)4 compound oozed gradiently from the pre-ceramic PCS to the surface layer after maturating time of 100 h. In the conditions of 45wt% Ti (OC4H9)4 and 100 h maturation, the nanometer-scale TiO2 particles on continuous surface layer were formed by SEM photographs. The nanometer-scale TiO2/SiC functional compositional film can modify the resistance to oxidation of carbon fiber.

关键词： polycarbosilane, TiO2/SiC nanometer-scale functional compositional film, CF, in situ formation.

Determination of combustion energies and the standard enthalpies of formation.for the complexes of RE(Et_(2)dtc)_(3)(phen)

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Science China Chemistry 2005年第Z1期48卷 88-92页

作者： YANG Xuwu ZHU Li CHEN Sanping GAO Shengli SHI Qizhen Department of Chemistry Shaanxi Key Laboratory of Physico-Inorganic Chemistry Northwest University Xi'an 710069 China Department of Chemistry Shaanxi Key Laboratory of Physico-Inorganic Chemistry Northwest University Xi'an 710069 China Department of Chemistry Shaanxi Key Laboratory of Physico-Inorganic Chemistry Northwest University Xi'an 710069 China Department of Chemistry Shaanxi Key Laboratory of Physico-Inorganic Chemistry Northwest University Xi'an 710069 China Department of Chemistry Shaanxi Key Laboratory of Physico-Inorganic Chemistry Northwest University Xi'an 710069 China

Solid complexes, RE(Et2dtc)3(phen) (RE=La, Pr, Nd, Sm-Lu), were synthesized hydrated lanthanide chlorides in absolute ethanol. The constant-volume combustion energies of complexes, △cU, were determined by a precise rotating-bomb calorimeter at 298.15 K. The standard enthalpies of combustion, AcHmθ, and standard enthalpies of formation. AfHmθ, were calculated for these complexes, respectively. The experiment results showed the "tripartite effect"of rare earth.

关键词： thermochemistry, combustion energies, calorimeter, RE(Et2dtc)3(phen), standard enthalpies of formation.

THERMAL INSTABILITY AND THE formation.MODEL OF GLOBULAR CLUSTERS FROM MERGING DWARF GALAXIES

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Science China Mathematics 1992年第11期35卷 1364-1373页

作者：马駬陈时俞允强 Beijing Astronomical Observatory Academia Sinica Beijing 100080 PRC Institute of Theoretical Physics Academia Sinica Beijing 100080 PRC Department of Physics Peking University Beijing 100871 PRC

A Viable scenario for globula r cluster formation.is suggested in CDM model.In this scenario the smaller scale fluctuations superpo sed on proto-galaxy will form proto-dwarf-galaxies. In their multi-phase ISM the warm clouds,which are thermally stable and gravitationally marginally stable with appropriate masses and metallicities, might be the proper progenitors of GCs.In the virialization of a proto-galaxy,these dwarf galaxies will acquire kinetic energy and collide with each other. As strong external disturbances. these collisions will cause a short timescale thermal instability,and further stimulate gravitational instability which is necessary for the transformation.of progenitors into GCs.

关键词： globular cluster galaxy formation.

The KDM4B–CCAR1–MED1 axis is a critical regulator of osteoclast differentiation and bone homeostasis

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Bone Research 2021年第3期9卷 323-335页

作者： Sun-Ju Yi You-Jee Jang Hye-Jung Kim Kyubin Lee Hyerim Lee Yeojin Kim Junil Kim Seon Young Hwang Jin Sook Song Hitoshi Okada Jae-Il Park Kyuho Kang Kyunghwan Kim Department of Biological Sciences and Biotechnology Chungbuk National UniversityCheongjuChungbukRepublic of Korea Korea Basic Science Institute Gwangju Center at Chonnam National UniversityGwangjuRepublic of Korea New Drug Development Center KBIO Osong Medical Innovation FoundationCheongjuChungbukRepublic of Korea Data Convergence Drug Research Center Therapeutics&Biotechnology DivisionKorea Research Institute of Chemical TechnologyDaejeonRepublic of Korea Department of Biochemistry Kindai University Faculty of MedicineOsakasayamaOsakaJapan

Bone undergoes a constant and continuous remodeling process that is tightly regulated by the coordinated and sequential actions of bone-resorbing osteoclasts and bone-forming osteoblasts.Recent studies have shown that histone demethylases are implicated in osteoblastogenesis;however,little is known about the role of histone demethylases in osteoclast formation.Here,we identified KDM4B as an epigenetic regulator of osteoclast differentiation.Knockdown of KDM4B significantly blocked the formation.of tartrate-resistant acid phosphatase-positive multinucleated cells.Mice with myeloid-specific conditional knockout of KDM4B showed an osteopetrotic phenotype due to osteoclast deficiency.Biochemical analysis revealed that KDM4B physically and functionally associates with CCAR1 and MED1 in a complex.Using genome-wide chromatin immunoprecipitation(ChIP)-sequencing,we revealed that the KDM4B–CCAR1–MED1 complex is localized to the promoters of several osteoclast-related genes upon receptor activator of NF-κB ligand stimulation.We demonstrated that the KDM4B–CCAR1–MED1 signaling axis induces changes in chromatin structure(euchromatinization)near the promoters of osteoclast-related genes through H3K9 demethylation,leading to NF-κB p65 recruitment via a direct interaction between KDM4B and p65.Finally,small molecule inhibition of KDM4B activity impeded bone loss in an ovariectomized mouse model.Taken together,our findings establish KDM4B as a critical regulator of osteoclastogenesis,providing a potential therapeutic target for osteoporosis.

关键词： formation. critical MED1

Perovskite crystallization

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Journal of Semiconductors 2021年第8期42卷 8-11页

作者： Lili Ke Liming Ding Hunan Key Laboratory for Micro-Nano Energy Materials and Devices School of Physics and OptoelectronicsXiangtan UniversityHunan 411105China Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China

In recent years,perovskite solar cells(PSCs)have attracted tremendous attention due to their high power conversion efficiencies(PCEs)and tailorable optoelectronic properties.Up to now,the certified PCE of lab-scale PSCs has climbed up to 25.5%(see https://www.***.gov/pv/cell-effi-ciency.html).However,there still exists a large efficiency gap between small-area devices and large-area solar modules.The main reason refers to the difference between morphology and crystallinity caused by different perovskite film formation.

关键词： properties. formation. perovskite

Arabidopsis EED1 encoding a plant-specific nuclear protein is essential for early embryogenesis

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Journal of Genetics and Genomics 2020年第1期47卷 61-64页

作者： Mai Yang Chun Yan Megan Griffith Jinping Zhao Yongbiao Zhang Daoxin Xie Jianbin Yan MOE Key Laboratory of Bioinformatics Tsinghua-Peking Joint Center for Life SciencesSchool of Life SciencesTsinghua UniversityBeijing100084China Beijing Advanced Innovation Center for Big Data-Based Precision Medicine Beihang UniversityBeijing100191China Institute of Molecular and Cell Biology Singapore117609Singapore

Embryogenesis is central to the life cycle of higher plants,which starts from division of the single-cell zygote and culminates in formation.of the mature embryo with major cell precursors.Such a process generally inv... 详细信息

关键词： formation. Arabidopsis pattern

Safflower Yellow Compounds Alleviate Okadaic Acid-Induced Impairment of Neurite Outgrowth in Differentiated SH-SY5Y Cells

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Biomedical and Environmental Sciences 2020年第10期33卷 812-816页

作者： WANG Zhen Hua SHI Xiao Bing LI Gang HAO Xue Yan YUAN Zhen Zhen CAO Xiao Hai WANG Hong Lun LI Ji MA Cheng Jun Center for Mitochondria and Healthy Aging College of Life SciencesYantai UniversityYantai 264005ShandongChina State Key Laboratory of Plateau Ecology and Agriculture Qinghai UniversityXining 810016QinghaiChina Key Laboratory of Tibetan Medicine Research Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008QinghaiChina

The dynamic assembly of microtubules plays a key role in maintaining structural and functional integrity of eukaryotic cel s,especial y with regard to neuronal differentiation or neurite outgrowth and synaptic plastic... 详细信息

关键词： Outgrowth formation. integrity

Super-large-scale structures in the distribution of infrared galaxies

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Science China Mathematics 1999年第8期42卷 873-882页

作者：邓祖淦夏晓阳 G.Borner Max-Planck-Institut for Astrophysik 85740 Garching

Typical scales in the distribution of IRAS galaxies with the unnormalized pair count method. Samples are those provided by QDOT redshift survey and sorted out from the IRAS faint sources catalog. Analysis is concentrated on the structures at super-large scales. The results show that statistically significant typical scales do exist in the distribution of all these samples from both 2-dimensional and 3-dimensional analyses. These scales are consistent with those found from the analyses of galaxies and clusters of galaxies by Mo et al. and also consistent with those found from analysis of quasars by Deng et al. The analysis provides additional evidence for the existence of typical scales in the large-scale structure of the universe. The existence of typical scales challenges all the existing models on the formation.of galaxies and structures.

关键词： cosmology large-scale structures galaxies evolution formation.