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Science China Chemistry 2024年第3期67卷 908-913页

作者： jun zhang Xuefeng Wang Peiqi Wang Jiayuan fang Shaoyu Li Jie Wu School of Pharmaceutical and Chemical Engineering&Institute for Advanced Studies Taizhou UniversityShanghai 200438China Department of Chemistry Fudan UniversityShanghai 200438China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

β-Chiral sulfones are structural motifs widely found in natural products and bioactive molecules, while also serving as important intermediates for the synthesis of valuable chiral scaffolds. In contrast to the rapid growth of sulfur dioxide insertion chemistry over the last decade, enantioselective catalytic variants for accessing β-chiral sulfones, especially those bearing a quaternary carbon stereocenter, remain rare. Herein, we report an enantioselective copper/bisoxazoline catalyzed oxysulfonylation of alkenes to yield isoxazolinyl-containing β-chiral sulfones bearing quaternary carbon stereocenters with moderate to excellent yields and up to 96:4 er. The advantage and irreplaceability of this sulfur dioxide insertion catalytic system have been demonstrated by achieving transformations clearly unavailable with the previously reported sulfonyl chloride system. Additionally,the recoverability of the new-developed bisoxazoline ligand L9 and its reusability without any erosion of the catalytic activity and enantioselectivity further demonstrate the usefulness of the protocol.

关键词： β-chiral sulfones sulfur dioxide insertion oxysulfonylation copper catalysis enantioselectivity

Experimental and first-principles calculation of TiN growth mechanism on CeAlO_(3) surface in steel

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Journal of Iron and Steel Research International 2024年第2期31卷 452-463页

作者： Fei-hu He jun Peng fang zhang Yong-bin Wang Hong-tao Chang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina

Regular TiN is harmful to the toughness of steel,and its shape and size need to be *** the behavior of TiN precipitation on CeAlO_(3) surfaces is critical for controlling the morphology and formation process of CeAlO_(3)–TiN composite inclusions in the *** results showed that TiN had a square morphology on the CeAlO3 surface,and electron backscatter diffraction phase identification results revealed the orientation relationship between CeAlO_(3) and TiN as follows:(001)_(CeAlO_(3))//(110)_(TiN),(100)_(CeAlO_(3))/(001)_(TiN),and[010]_(CeAlO_(3))/[110]_(TiN).The CeAlO3 crystal structure was studied using the first-principles calculation method,and the adsorption and growth process of TiN on the CeAlO_(3) surface were investigated from the atomic *** calculation results indicate that there is no metallic bonding present in the CeAlO_(3) *** the low-index crystal planes of CeAlO_(3),the(110)planes terminated with O and CeAlO have the highest and lowest surface energies,respectively,with values of 0.373 and 0.051 eV/Å^(2).On the high surface energy plane of CeAlO_(3),the TiN atomic permutation structure is consistent with the arrangement of Ti and N atoms in TiN(100)or(110).For the low surface energy plane of CeAlO_(3),the Ti and N atoms are arranged in a ring-like structure.

关键词： CeAlO_(3)-TiN inclusion Orientation relationship Crystal structure First principle Surface energy

An innovative classification system for ranking the biological effects of marine aromatic hydrocarbons based on fish embryotoxicity

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Acta Oceanologica Sinica 2024年第6期43卷 153-162页

作者： Ronghui Zheng Chao fang Fukun Hong Min zhang Fulong Gao Yusheng zhang jun Bo Key Laboratory of Marine Ecological Conservation and Restoration Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China Observation and Research Station of Coastal Wetland Ecosystem in Beibu Gulf Ministry of Natural ResourcesBeihai 536015China

Petroleum hydrocarbon pollution is a global concern,particularly in coastal *** aromatic hydrocarbons(PAHs) are regarded as the most toxic components of petroleum *** this study,the biomonitoring and ranking effects of petroleum hydrocarbons and PAHs on the marine fish model Oryzias melastigma embryos were determined in the Jiulong River Estuary(JRE) and its adjacent waters in *** results showed that the levels of petroleum hydrocarbons from almost all sites met the primary standard for marine seawater quality,and the concentrations of the 16 priority PAHs in the surface seawater were lower compared with those in other coastal areas worldwide.A new fish expert system based on the embryotoxicity of ***(OME-FES) was developed and applied in the field to evaluate the biological effects of petroleum hydrocarbons and *** selected physiological index and molecular indicators in OME-FES were appropriate biomarkers for indicating the harmful effects of petroleum hydrocarbons and *** outcome of OME-FES revealed that the biological effect levels of the sampling sites ranged from level Ⅰ(no stress) to level Ⅲ(medium stress),which is further corroborated by the findings of nested analysis of variance(ANOVA) *** results suggest that the OME-FES is an effective tool for evaluating and ranking the biological effects of marine petroleum hydrocarbons and *** method may also be applied to evaluate other marine pollutants based on its framework.

关键词： petroleum hydrocarbons polycyclic aromatic hydrocarbons fish expert system integrated biomarker response nested one-way analysis of variance

Cuproptosis mediates copper-induced testicular spermatogenic cell death

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Asian Journal of Andrology 2024年第3期26卷 295-301页

作者： Jing-Yi zhang Xu-jun Yu jun-jun Li Yao Xiao Guang-Sen Li fang Yang Liang Dong Chengdu University of Traditional Chinese Medicine Chengdu 611137China Chengdu Fifth People’s Hospital The Fifth People’s Hospital of Chengdu University of Traditional Chinese MedicineChengdu 611130China TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072China Department of Surgery The Reproductive and Women-Children HospitalChengdu University of Traditional Chinese MedicineChengdu 610041China

Cuproptosis,a novel mechanism of programmed cell death,has not been fully explored in the context of spermatogenic *** investigated the potential involvement of cuproptosis in spermatogenic cell death using a mouse model of copper *** male Institute of Cancer Research(ICR)mice were randomly divided into four groups that received daily oral gavage withsodium chloride(control)or copper sulfate(CuSO_(4))at 50 mg kg^(−1),100 mg kg^(−1),or 200 mg kg^(−1),for 42 consecutive *** to copper overload exhibited a disruption in copper ***,significant upregulated expression of keycuproptosis factors was accompanied by a significant rise in the rates of testicular tissue cell *** revealed the presence of ferredoxin 1(Fdx1)in Sertoli cells,Leydig cells,and spermatogenic cells at various stages oftesticular development,and the Fdx1-positive staining area was significantly increased in copper-overloaded *** and decreased adenosine triphosphate levels were also observed,further implicating mitochondrial damage *** analyses revealed pathological lesions and blood−testis barrier destruction in the testicular tissue,accompaniedby decreased sperm concentration and motility,in copper-overloaded *** summary,our results indicate that copper-overloadedmice exhibit copper homeostasis disorder in the testicular tissue and that cuproptosis participates in spermatogenic cell *** findings provide novel insights into the pathogenic mechanisms underlying spermatogenic cell death and provide initialexperimental evidence for the occurrence of cuproptosis in the testis.

关键词： blood−testis barrier cuproptosis ferredoxin 1 spermatogenic cell death

城市人工湖泊浮游植物群落结构及环境因子分析

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水生态学杂志 2024年第2期45卷 92-101页

作者：魏秘王瑞王竹周连凤张俊芳王辉吕克强韩增辉彭增辉胡菊香水利部中国科学院水工程生态研究所水利部水工程生态效应与生态修复重点实验室湖北武汉430079 湖南湘新水务环保投资建设有限公司湖南长沙410006 湖南水天地环保科技有限公司湖南长沙410006

探究梅溪湖浮游植物群落结构与环境因子的关系,为城市人工湖泊水生态系统修复与治理提供基础资料与理论依据。2020-2021年布设7个采样点按季度进行采样,分析浮游植物群落组成、时空分布及其与环境因子的关系。结果显示4个季度梅溪湖水... 详细信息

探究梅溪湖浮游植物群落结构与环境因子的关系,为城市人工湖泊水生态系统修复与治理提供基础资料与理论依据。2020-2021年布设7个采样点按季度进行采样,分析浮游植物群落组成、时空分布及其与环境因子的关系。结果显示4个季度梅溪湖水体溶解氧、pH、氨氮、高锰酸盐指数等指标均处于Ⅱ类水质标准范围内,总磷处于Ⅱ~Ⅲ类水质标准,总氮在春秋冬季含量较高。共在梅溪湖检出浮游植物7门96种,其中以绿藻、硅藻和蓝藻种类数居多,共占总种类数的86.46%,主要优势种为细小隐球藻(Aphanocapsa elacjista)、小环藻(Cyclotella sp.)、链状曲壳藻(Achnanthes catenata)和尖尾蓝隐藻(Chroomonas acuta),优势种具有明显季节交替性。浮游植物年均密度为(23.97±9.95)×10^(6)个/L,各季度东部水域密度均高于西部水域;多样性指数评价结果表明梅溪湖水体处于中度污染和中-富营养状态,与水质评价结果基本一致。浮游植物与环境因子基于转化的冗余分析结果显示,水温、氧化还原电位、总氮和亚硝酸盐氮是影响梅溪湖浮游植物群落的主要驱动因子。控制总氮等营养盐的输入是改善梅溪湖水质和营养状态的有效手段。

关键词：人工湖泊浮游植物环境因子群落结构梅溪湖

FPGA-based position reconstruction method for neutron beam flux spatial distribution measurement in BNCT

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Nuclear Science and Techniques 2024年第3期35卷 96-108页

作者： Wei Jiang Ping Cao Yi-Ming Wu Xian-Ke Liu Zhu-jun fang Zhi-Yong zhang Bin Shi jun Chen State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China National Key Laboratory for Metrology and Calibration Techniques China Institute of Atomic EnergyBeijing 102413China

A new measurement method for the spatial distribution of neutron beam flux in boron neutron capture therapy(BNCT)is being developed based on the two-dimensional Micromegas *** address the issue of long processing times in traditional offline position reconstruction methods,this paper proposes a field programmable gate array based online position reconstruction method utilizing the micro-time projection chamber *** method encapsulates key technical aspects:a self-adaptive serial link technique built upon the dynamical adjustment of the delay chain length,fast sorting,a coordinate-matching technique based on the mapping between signal timestamps and random access memory(RAM)addresses,and a precise start point-merging technique utilizing a circular combined *** performance test of the selfadaptive serial link shows that the bit error rate of the link is better than 10-12 at a confidence level of 99%,ensuring reliable data *** experiment utilizing the readout electronics and Micromegas detector shows a spatial resolution of approximately 1.4 mm,surpassing the current method’s resolution level of 5 *** beam experiment confirms that the readout electronics system can obtain the flux spatial distribution of neutron beams online,thus validating the feasibility of the position reconstruction *** online position reconstruction method avoids traditional methods,such as bubble sorting and traversal searching,simplifies the design of the logic firmware,and reduces the time complexity from O(n2)to O(n).This study contributes to the advancement in measuring neutron beam flux for BNCT.

关键词： Position reconstruction FPGA Readout electronics Neutron flux spatial distribution

Magnetic NiFe_(2)O_(4)@FeNi_(3)core-shell nanospheres derived from FeNi-LDH precursor anchoring on rGO nanosheets for enhanced electromagnetic wave absorption

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Journal of Materials Science & Technology 2024年第4期171卷 101-114页

作者： Kunyao Cao Yuan fang Shuai Wang Yue zhang Jiayue Wen jun Chen Rui Zhao Weidong Xue School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054China

Graphene has been extensively utilized in the domain of electromagnetic wave(EMW)absorption ma-terials because of its excellent electrical ***,the inferior impedance matching per-formance and the single loss mechanism vastly restrict the ***,it’s an effective strat-egy to solve these issues by introducing magnetic ***,layer double hydroxide(LDH)is an appropriate template to obtain magnetic component *** that ferromagnetic met-als such as Fe,Co,Ni,and their corresponding metal oxides are usually treated as magnetic compo-nents which are promising candidates for EMW absorption ***,in this work,a FeNi-layered double hydroxide-reduced graphene oxide(FeNi-LDH-rGO)aerogel was synthesized through a series of processes such as electrostatic self-assembly,hydrothermal,freeze-drying,and *** magnetic NiFe_(2)O_(4)@FeNi_(3)core-shell nanospheres were obtained from FeNi-LDH precursor,anchoring on rGO nanosheets after the annealing ***,the effects of different mass ratios of LDH to GO as well as different annealing temperatures of LDH-rGO aerogel on the EMW absorption prop-erty and impedance matching performance were *** a consequence,the fabricated ultralight 600LDH-rGO 2:1 aerogel shows a broad effective absorption bandwidth(EAB)of 7.04 GHz at a thickness of 2.3 mm with a low filling content of only 6 wt%and a low density of 4.4 mg/cm^(3).In conclusion,the synthetic LDH-rGO aerogels offer an effective strategy for preparing EMW absorption materials that own three-dimensional porous network structure and unique magnetic NiFe_(2)O_(4)@FeNi_(3)core-shell struc-ture nanospheres.

关键词： Electrostatic self-assembly Electromagnetic wave absorption LDH-rGO aerogel Layered double hydroxide Reduced graphene oxide NiFe_(2)O_(4)@FeNi_(3)core-shell structure

Antibacterial and cytotoxic metabolites produced by Streptomyces tanashiensis BYF-112 isolated from Odontotermes formosanus

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Chinese Journal of Natural Medicines 2024年第9期22卷 822-830页

作者： WU jun SONG Tao zhang Le HUANG Zhongdi HUANG fang YIN Caiping zhang Shuxiang LIU Xinhua zhang Yinglao School of Life Science Anhui Agricultural UniversityHefei 230036China School of Pharmacy Anhui Medical UniversityHefei 230036China

Chemical investigations of the termite-associated Streptomyces tanashiensis BYF-112 resulted in the discovery of four novel alkaloid derivatives: vegfrecines A and B(1 and 2), exfoliazone A(3), and venezueline H(7), in addition to nine known metabolites(4-6, 8-13). The structures of these compounds were elucidated through comprehensive spectroscopic analysis and comparison with existing literature data. Antibacterial assays revealed that viridomycin A(11) exhibited potent antibacterial activity against Staphylococcus aureus, with a zone of inhibition(ZOI) of 12.67 mm, in comparison to a ZOI of 17.67 mm for the positive control gentamicin sulfate. Viridomycin A(11) showed moderate activity against Micrococcus tetragenus and Pseudomonas syringae pv. actinidae, with ZOI values of 15.50 and 14.33 mm, respectively, which were inferior to those of gentamicin sulfate(34.67 and 24.00mm). Viridomycin F(12) also exhibited moderate antibacterial effects against S. aureus, M. tetragenus, and P. syringae pv. actinidae,with ZOI values of 8.33, 16.50, and 10.83 mm, respectively. Cytotoxicity assays demonstrated that viridobruunine A(5), exfoliazone(6), viridomycin A(11), and X-14881E(13) exhibited significant cytotoxicity against human malignant melanoma(A375), ovarian cancer(SKOV-3), and gastric cancer(MGC-803) cell lines, with IC_(50) values ranging from 4.61 to 19.28 μmol·L^(-1). Furthermore, bioinformatic analysis of the complete genome of S. tanashiensis suggested a putative biosynthetic gene cluster(BGC) responsible for the production of compounds 1-12. These findings indicate that the secondary metabolites of insect-associated S. tanashiensis BYF-112hold promise as potential sources of novel antibacterial and anticancer agents.

关键词： Odontotermes formosanus Streptomyces tanashiensis Alkaloid Cytotoxic activity Antibacterial activity Biosynthetic pathway

Climate-Vegetation Coverage Interactions in the Hengduan Mountains Area, Southeastern Tibetan Plateau, and Their Downstream Effects

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Advances in Atmospheric Sciences 2024年第4期41卷 701-716页

作者： Congxi fang Jinlei CHEN Chaojun OUYANG Lu WANG Changfeng SUN Quan zhang jun WEN Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610299China State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710049China The State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China College of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China

Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in the *** study,using multisource datasets(including satellite data and meteorological observations and reanalysis data)revealed the mutual feedback mechanisms between changes in climate(temperature and precipitation)and vegetation coverage in recent decades in the Hengduan Mountains Area(HMA)of the southeastern TP and their influences on climate in the downstream region,the Sichuan Basin(SCB).There is mutual facilitation between rising air temperature and increasing vegetation coverage in the HMA,which is most significant during winter,and then during spring,but insignificant during summer and *** temperature significantly enhances local vegetation coverage,and vegetation greening in turn heats the atmosphere via enhancing net heat flux from the surface to the *** atmospheric heating anomaly over the HMA thickens the atmospheric column and increases upper air *** high pressure anomaly disperses downstream via the westerly flow,expands across the SCB,and eventually increases the SCB *** effect lasts from winter to the following spring,which may cause the maximum increasing trend of the SCB temperature and vegetation coverage in *** results are helpful for estimating future trends in climate and eco-environmental variations in the HMA and SCB under warming scenarios,as well as seasonal forecasting based on the connection between the HMA eco-environment and SCB climate.

关键词： Hengduan Mountains Area normalized difference vegetation index climate change net heat flux downstream effects

The reservoir characteristics and their controlling factors of the sublacustrine fan in the Paleogene Dongying Formation, Bohai Sea,China

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Journal of Palaeogeography 2024年第1期13卷 127-148页

作者： Xiao-jun Pang Guan-Min Wang Meng Zhao Qing-Bin Wang Xue-fang zhang School of Geosciences China University of Petroleum(East China)QingdaoShandong 266580China Tianjin Branch of China National Offshore Oil Corporation Limited Tianjin 300459China

Sublacustrine fan is an important element in continental lacustrine basins and is significant for reservoir exploration. Oil and gas resources have been found in the sublacustrine fan sandstone reservoirs of the Paleogene Dongying Formation in the Bohai Sea. In this study, the characteristics of the sublacustrine fan reservoirs and the controlling factors are studied using information from logging, cores, physical properties,casting thin sections, X-ray diffraction of clay minerals, vitrinite reflectance, rock pyrolysis, manometry data,and 3D seismic data. The sublacustrine fans of the Dongying Formation in the LD10, QHD34, and BZ21 structures show high-quality reservoirs with porosity >15 % and permeability >5 m D. The main controlling factors of the high-quality reservoirs are attributed to the favorable sedimentary facies type and negligible compaction,and cementation, substantial dissolution of K-feldspar, overpressure, and the development of faults and fractures. A high-quality sublacustrine fan reservoir model has been established to explain how these factors affected the physical properties. The favorable targets for oil and gas exploration in the Dongying Formation of Bohai Sea include undercompacted sandy debris flow reservoirs showing the dissolution of K-feldspar, and the reservoirs which are connected to the source rocks by faults. This study provides insights to establish the relationship between sedimentology, diagenesis and reservoir quality. The results of this study are significant for the exploration and development of the sublacustrine fan sandstone reservoirs in the Bohai Sea and analogous sandstone reservoirs elsewhere.

关键词： Sublacustrine fan High-quality reservoir Dissolution Overpressure Fault Bohai Sea