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Synthesis and Crystal Structure of[(CH_3)_4N]_4,H_2[ZnW_(11)SnO_(39)]·9H_2O

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Chinese Journal of Structural Chemistry 1998年第1期17卷 31-34页

作者： YANG Qi-Hua dai hui-cong LIU Jing-Fu(Department of Chemostry, Northeast Normal University, Changchun 130024)XING Yan LIN Yong-Hua JIA Heng-Qing(Institute of Applied Chemistry, the Chinese Academy of Science, Changchun 130022) Department of Chemistry Northeast Normal University Changchun 130024 China Institute of Applied Chemistry Chinese Academy of Science Changchun 130022 China

The complex [(CH_3)_4N]_4,H_2[ZnW_(11)SnO_(39)]·9H_2O Crystallizes in themonoclinic space group P21/m with cell dimensions: a=13. 164(3) A, b=21. 502(4)A, c=13. 234(3) A, a=90, β=91. 70(3), r=90, V=3744. 3(13) A3, Z=4,Mr= 3307. 15, Dc= 2. 933 g/cm3, A (MoKa ) = 0. 71073 A, u=175. 45 cm-1,F(000) = 2956, T= 293K, R=0. 0801 for 8401 observed reflections. The anion in thetitle compound is of a-typekeggin structure.

关键词： Synthesis crystal structure heteropoly compound

Crystal Structures of Two New Monoprotonated Products of 1,4,7 trimethyl-1,4,7-triazacyclononane: （Me3〔9〕aneN3H）(SO3CF3) and （Me3〔9〕aneN3H）I

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Chinese Journal of Structural Chemistry 2000年第1期19卷 48-52页

作者： DENG Dao Lia * ZHANG Yan hui a dai cong Yun a ZENG Hong a YAN Zhi Qing a YE Chang Qing a Ronald Ha\|Ge ba (Unilever Research SIOC, 354 Fenglin Road, Shanghai 200032. China) b (Unilever Research Laboratorium, Olivier van Noor Unilever Research SIOC 上海 2 0 0 0 32 Unilever Research Laboratorium 荷兰 Vlaardinge

Two new monoprotonated products of macrocyclic polyamine 1,4,7 trimethyl 1,4,7 triazacyclononane(Me 3〔9〕aneN 3), (Me 3〔9〕aneN 3H)(SO 3CF 3) 1 (C 10 H 22 N 3O 3SF 3, M r =321.36) and (Me 3〔9〕aneN 3H)I 2 (C 9H 22 N 3I, M r =299.20) were obtained by the reactions of Me 3〔9〕aneN 3 and yttrium triflate or ytterbium diiodide as the unexpected products. The crystal structures of compounds 1 and 2 have been determined. Crystal 1 is orthorhombic, space group P2 12 12 1(#19), a =12.609(3), b=13.531(1), c=9.225(3) , V=1573.9(7)  3, Z=4, D c= 1.356 g/cm 3, μ =2.47 cm -1 , F (000)=680 and R=0.052, R w =0.052 for 807 unique reflections with I>2σ(I) . Crystal 2 belongs to the orthorhombic system with space group P2 12 12 1(#19), a=11.417(2), b=13.099(3), c=8.762(2) , V=1310.5(4)  3, Z=4, D c =1\^516 g/cm 3, μ =24.14 cm -1 , F (000)=600 and R=0.035, R w =0.042 for 1427 unique reflections with I>3σ(I) . The two structures contain the same cyclic framework in which the acid proton is bonded to an amine nitrogen. This proton exhibits strong intramolecular hydrogen bonds with the other two nitrogen atoms. The methyl groups are directed away from the ring cavity. The bond distance between acid proton and an amine nitrogen in compound 2 is extremely short. The bond angles for 1 and 2 also exhibit obvious diversity inside of triazacyclononae.

关键词： formation crystal structure protonation triazacyclononane

High-temperature oxidation behavior and degradation mechanism of chromium-coated zirconium alloy cladding: a review

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Tungsten 2025年第1期7卷 50-70页

作者： Yi Li Bei-Qi Wang Xin-Yin Zhang Shi-Jie Wang cong-Yi Li hui-Long Yang Ran-Ran Su Tong Liu School of Mechanical Engineering Shanghai Jiao Tong University College and Graduate School of Arts and Sciences University of Virginia Global Institute of Future Technology Shanghai Jiao Tong University

Accident-tolerant fuels(ATF) have been extensively studied to reduce the production rate and total amount of heat and hydrogen generated from high-temperature steam oxidation during severe ***-coated zirconium alloy cladding has become one of the most promising candidates for ATF because of its excellent corrosion and oxidation *** paper provides a comprehensive overview of the research progress on oxidation behaviors and degradation mechanisms in chromium-coated zirconium alloy cladding under high-temperature *** techniques to strengthen the oxidation resistance are highlighted and ***,challenges and opportunities for various future directions are addressed.

关键词： Accident-tolerant fuel Chromium coating Degradation mechanism High-temperature oxidation behavior Zirconium alloy cladding

Contribution of fungal biomass to persistent soil carbon across natural ecosystems

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Science China Earth Sciences 2025年

作者： Xiang WANG Guang-hui YU Yakov KUZYAKOV Bo-Hao YIN Andreas KAPPLER cong-Qiang LIU Bohai Coastal Critical Zone National Observation and Research Station Institute of Surface-Earth System Science School of Earth System Science Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim Tianjin University Department of Soil Science of Temperate Ecosystems Department of Agricultural Soil Science University of G?ttingen Agro-Technological Institute Peoples Friendship University of Russia (RUDN University) Geomicrobiology Center for Applied Geosciences University of Tübingen Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infection University of Tübingen

Fungi are known to be crucial in the formation and stabilization of soil organic matter through their exudates and dead residues (necromass). Yet, it remains unclear how fungi contribute to the persistence of carbon in soils over millennial scales across biomes. Here, this study fills the knowledge gap by linking fungal carbon stocks with minerals-associated carbon stocks across major biomes. A strong correlation between fungal biomass and reactive mineral-associated carbon stocks in soils across six biomes supports the substantial role of fungi in soil carbon persistence at the global level. High spatial resolution nanoscale secondary ion mass spectrometry revealed that fungi may stabilize carbon by forming organo-mineral associations through their close physical connection to reactive minerals and weathered nanoparticles. We propose a conceptual model that emphasizes the dualistic role of hypha-mineral interactions:(i) fungi accelerate organic matter decomposition by producing reactive oxygen species on the hypha-mineral interfaces, and (ii) fungi stabilize their residues on mineral surfaces, leading to millennial scale persistence of soil C. Concluding, fungi play a fundamental role in ecosystems that extends beyond the decomposition of persistent carbon. They are crucial in stabilizing carbon on mineral surfaces, thereby facilitating the long-term removal of carbon from rapid biotic cycling.

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Gamma oscillations and their role in orchestrating balance and communication following stroke

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Neural Regeneration Research 2025年第2期20卷 477-478页

作者： Montana Samantzis cong Wang Matilde Balbi Queensland Brain Institute The University of QueenslandBrisbaneQLDAustralia Engineering Research Centre of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghaiChina

Induced brain oscillations in the gamma range have recently garnered attention due to their reported neuroprotective effects in the treatment of Alzheimer’s *** method differs from pharmacological approaches by tapping into the neuronal population dynamics that underlie the homeostatic processes in the brain that are crucial for the recovery of ***,induced gamma-range oscillations have been used to improve cerebral blood flow,motor function,and synaptic plasticity in a mouse model of focal stroke,highlighting the broad potential of recruiting intrinsic recovery processes for the treatment of neurological *** open questions,such as the frequency specificity of the benefits,will shed light on the intrinsic processes involved and allow clinicians to optimize recovery after stroke.

关键词： protective specificity Alzheimer

新型手性膦配体的合成及其在不对称催化中应用的新进展

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分子催化 2000年第6期14卷 426-440页

作者：戴慧聪陈惠麟郑卓张遂之张秀峰中国科学院大连化学物理研究所大连116023

光学活性的膦配体在过渡金属催化的不对称合成中起着非常重要的作用。到目前为止，已相继出现2000多个新手性膦配体。经多年的大量研究积累，以BINAP为代表的几个手性膦配体已用于生产有用的光学活性物质。工业上应用的成功极大地推动... 详细信息

光学活性的膦配体在过渡金属催化的不对称合成中起着非常重要的作用。到目前为止，已相继出现2000多个新手性膦配体。经多年的大量研究积累，以BINAP为代表的几个手性膦配体已用于生产有用的光学活性物质。工业上应用的成功极大地推动了手性膦化学的基础研究。目前，对新型的不对称催化反应的探索以及新的手性膦配体的设计合成研究非常活跃~[1]。本文重点介绍1990年以后报导的手性膦配体的合成及其在不对称催化反应方面的应用。

关键词：光学活性膦配体 p-手性膦配体合成不对称催化

Approach from the laboratory to the field: New strategies in the control of mosquito-borne infectious diseases

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Science China Life Sciences 2025年第1期68卷 303-305页

作者： Ziqian Xu Lianpan dai Jun Liu National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases (NITFID) National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and Prevention CAS Key Laboratory of Pathogen Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences

Vector-borne viruses, transmitted among humans and animal hosts through bites of vectors such as mosquitoes and ticks,pose a great and ongoing threat to public health and biosafety(Yang et al., 2022).Among them, dengue virus-induced epidemics, have dramatically increased worldwide in recent decades. The report released by the World Health Organization(WHO) at the end of 2023 showed that dengue epidemic globally surged in2023, with the number of reported cases nearing a historical peak.

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Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan Guo Hong-Bo Jin cong-Feng Qiao Yue-Liang Wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

Emerging trends in the selective production of value-added aromatics

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Science China Chemistry 2025年第1期68卷 15-20页

作者： Yuchao Wu Houliang dai Weisheng Yang Yaxing Li Lichen Liu Petrochemical Research Institute Company Limited China National Petroleum Corporation Engineering Research Center of Advanced Rare Earth Materials Department of Chemistry Tsinghua University

1 Introduction Aromatics (mainly benzene, toluene, and xylenes, BTX) are essential intermediates in the chemical industry. They are employed in the synthesis of a broad spectrum of chemicals and materials, e.g., various polymers, plastics, resins, solvents, dyes, pharmaceuticals [1]. The manufacturing pathway of BTX mainly includes petroleum reforming of naphtha, coal-to-aromatics, methanol-to-aromatics [2].

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