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Chinese Chemical Letters 2024年第10期35卷 452-456页

作者： Jun-jie Fang Zheng Liu Yun-Peng xie Xing Lu State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

In core-shell silver nanoclusters,the control of core structure presents a more formidable challenge compared to that of the shell ***,we report the successful synthesis and characterization of four distinct silver thiolate nanoclusters[MS_(4)@Ag_(12)@Ag_(46)S_(24)(dppb)_(12)](M=Mo or W),each incorporating a cup-like[MS_(4)@Ag_(12)]^(2+)*** nanoclusters were meticulously prepared using(NH_(4))2Mo S4or(NH_(4))_(2)WS_(4)as both a template and a controlled source of ***,we have observed a unique configuration within these eight-electron superatomic Ag_(58) nanoclusters,where the zerovalent Ag atoms reside exclusively within the inner[MS_(4)@Ag_(12)]^(2+)*** stands in contrast to other superatomic clusters possessing an Ag(0)***,the introduction of phenyl-containing compounds during the synthesis process induced a transformation in the space group symmetry from C_(2)/c to I 4ˉ.This transformative effect was found to originate from the interplay between adjacent 1,4-bis(diphenylphosphino)butane(dppb)ligands,which facilitated enhanced emission through aggregationinduced intermolecular interactions,specifically C-H···π***,our findings contribute substantively to the understanding of the intricate relationship between nanocluster structures and their corresponding properties,shedding light on the crucial roles played by templates and diphosphine ligands in this context.

关键词： Superatom Silver nanocluster Template synthesis Photoluminescence Aggregation-induced emission

Elevated CO_(2) increases soil redox potential by promoting root radial oxygen loss in paddy field

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Journal of Environmental Sciences 2024年第2期136卷 11-20页

作者： jie Li Han Zhang Wenyi xie Cheng Liu Xiaoyu Liu Xuhui Zhang Lianqing Li Genxing Pan Institute of Resource Ecosystem and Environment of AgricultureNanjing Agricultural UniversityNanjing 210095China College of Agriculture Nanjing Agricultural UniversityNanjing 210095China

Soil redox potential(Eh)plays an important role in the biogeochemical cycling of soil *** its effect soil process and nutrients'availability under elevated atmospheric CO_(2) concentration and warming has seldom been ***,in this study,a field experiment was used to elucidate the effect of elevated CO_(2) concentration and warming on soil Eh,redox-sensitive elements and root radial oxygen loss(ROL).We hypothesized elevated CO_(2) and warming could alter soil Eh by promoting or inhibiting *** found that soil Eh in the rhizosphere was significantly higher than that of *** CO_(2) enhanced soil Eh by 11.5%,which corresponded to a significant decrease in soil Fe^(2+)and Mn^(2+)*** elevated CO_(2),the concentration of Fe^(2+)and Mn^(2+)decreased by 14.7%and 13.7%,*** also found that elevated CO_(2) altered rice root aerenchyma structure and promoted rice root *** elevated CO_(2),rice root ROL increased by 79.5%and 112.2%for Yangdao 6 and Changyou 5,*** had no effect on soil Eh and rice root *** warming increased the concentration of Mn^(2+)and SO_(4)^(2-)by 4.9%and 19.3%,*** was a significant interaction between elevated CO_(2) and warming on Fe^(2+)and Mn^(2+).Under elevated CO_(2),warming had no effect on the concentration of Fe^(2+)but decreased Mn^(2+)concentration *** study demonstrated that elevated atmospheric CO_(2) in the future could increase soil Eh by promoting rice root ROL,which will alter some soil nutrients'availability,such as Fe^(2+)and Mn^(2+).

关键词： Atmospheric CO_(2)enrichment Global warming Soil redox potential FACE Rice root aerenchyma

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有机分子在铁磁界面处的自旋极化研究

物理学报 2015年第18期64卷 199-204页

作者：伊丁武镇杨柳戴瑛解士杰山东大学物理学院、晶体材料国家重点实验室济南250100

采用第一性原理计算的方法,通过改变有机苯分子与密排六方Co(0001)面之间的不同接触方式,研究了多种接触构型下有机分子界面的自旋极化.计算发现,Co原子的3d电子与苯的C原子的2p电子之间存在耦合,导致费米能级处上下两种自旋的态密度不... 详细信息

采用第一性原理计算的方法,通过改变有机苯分子与密排六方Co(0001)面之间的不同接触方式,研究了多种接触构型下有机分子界面的自旋极化.计算发现,Co原子的3d电子与苯的C原子的2p电子之间存在耦合,导致费米能级处上下两种自旋的态密度不再相等,苯分子自旋简并解除,出现明显的自旋极化.自旋极化度随着分子与Co电极距离的变化,呈现出反转的特性.

关键词：有机铁磁界面自旋极化吸附第一性原理

Slope-climbing of cropland and its effects in China

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Journal of Mountain Science 2024年第8期21卷 2754-2769页

作者： CHEN Wanxu xie Youping YUAN Jintao ZENG jie YANG Liyan GU Tianci LEI Fan Hubei Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China Key Laboratory of Natural Resources Monitoring and Supervision in Southern Hilly Region Ministry of Natural ResourcesChangsha 410118China Yunnan Key Laboratory of Plateau Geographic Processes and Environmental Changes Faculty of GeographyYunnan Normal UniversityKunming 650500China

In recent decades,the spatio-temporal patterns of China’s croplands have been reshaped by disturbances from anthropogenic activities,with complex changes in the topographic characteristics of ***-climbing of croplands(SCCL)is an important issue that threatens sustainable agricultural *** providing land with prominent location advantages,SCCL weakens the water and fertilizer retention capacity for cropland,intensifies various geological disasters,and adversely affects the ecological environment and food yield of these *** is crucial to determine the spatio-temporal variation features and effects of SCCL in China to formulate more accurate cropland protection policies and to maintain food security;however,the current lack of relevant studies is detrimental for capturing trends in cropland resources and sustainable cropland *** this study,we constructed a multi-scale slope spectrum for cropland and total terrain to explore the spatial differences and trends of SCCL from a three-dimensional *** evaluated the natural and socioeconomic effects of SCCL in China from multiple *** indicate that the proportion of cropland with slopes below 2°,5°,and 6°in China decreased by 0.43%,0.47%,and 0.50%from 1980 to 2020,*** became apparent during 1980-1990 and 2010-2020,especially over the recent *** cropland climbing index(CCI)and upper limited slope change(ULSC)to measure the spatio-temporal pattern of SCCL were 0.99%and 1.17°,respectively,during *** the agricultural regional scale,the SCCL was also concentrated in 1980-1990 and 2010-2020,and it is more pronounced in the southern *** proportion of provinces and prefecture-level cities with high-intensity SCCL during 1980-2020 were 87.10%and 49.73%,*** was comparatively more pronounced and broader from 2010 to *** this period,17.84%of prefecture-level cities had no SCCL,and the average CCI for all prefecture-level citi

关键词： Croplands Slope spectrum Slope-climbing Three-dimensional perspective Multi-scale China

Hydrocarbon Charging and Accumulation Process of the Large Bozhong19-6 Condensate Gas Reservoirs in the Southwestern Bozhong Sub-Basin,Bohai Bay Basin,China

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Journal of Earth Science 2024年第2期35卷 613-630页

作者： Quanyun Miao Changgui Xu Fang Hao Minjunshi xie Qi Wang jie Yin Huayao Zou General Prospecting Institute of China National Administration of Coal Geology Beijing100039China State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing102249China Tianjin Branch of China National Offshore Oil Company Ltd. Tianjin300452China School of Geosciences China University of PetroleumQingdao266580China School of Geosciences Yangtze UniversityWuhan430100China

The Bozhong19-6(BZ19-6)condensate gas reservoirs,located in the southwestern Bozhong sub-basin,Bohai Bay Basin,China,were paleo-oil reservoirs in the geological past and have undergone at least three successive hydrocarbon charging *** hydrocarbon migration and accumulation process of“early oil and late gas”has occurred in the current *** the end of the sedimentation of the Guantao Formation(N_(1)g,∼12 Ma),the reservoirs began to fill with first stage low-moderate mature crude *** the late stage of the Lower Minghuazhen Formation(N_(1)ml)(∼6.7 Ma),the reservoirs were largely charged with second stage high mature crude *** the deposition of the upper Minghuazhen Formation(N_(2)m^(u),∼5.1 Ma),the paleo-oil reservoirs were transformed into shallow Neogene reservoirs due to the reactivation of basement *** the late stage of the N_(2)m^(u)to the present day(∼2.8–0 Ma),the reservoirs were rapidly filled by natural gas within a short *** addition,analysis of the formation of the reservoir bitumen and the conspicuous loss of the lower molecular weight n-alkanes in the crude oil reveal that the injection of a large amount of gas in the late stage caused gas flushing of the early charged oil.

关键词： Bohai Bay Basin BZ19-6 condensate gas reservoirs fluid inclusions hydrocarbon charging and accumulation petroleum geology

TSC prediction and dynamic control of BOF steelmaking with state-of-the-art machine learning and deep learning methods

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Journal of Iron and Steel Research International 2024年第1期31卷 174-194页

作者： Tian-yi xie Cai-dong Zhang Quan-lin Zhou Zhi-qiang Tian Shuai Liu Han-jie Guo Material Technology Research Institute Hesteel GroupShijiazhuang050023HebeiChina Tangsteel Company Hesteel GroupTangshan063611HebeiChina School of Artificial Intelligence Beijing Technology and Business UniversityBeijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

Mathematical(data-driven)models based on state-of-the-art(SOTA)machine learning and deep learning models and data collected from 12,786 heats were established to predict the values of temperature,sample,and carbon(TSC)test,including temperature of molten steel(TSC-Temp),carbon content(TSC-C)and phosphorus content(TSC-P),which made prepa-ration for eliminating the TSC *** maximize the prediction accuracy of the proposed approach,various models with different inputs were implemented and compared,and the best models were applied to the production process of a Hesteel Group steelmaking plant in China in the *** number of tabular features(hot metal information,scrap,additives,blowing practices,and preset values)was expanded,and time series(off-gas profiles and blowing practice curves)that could reflect the entire steelmaking process were introduced as ***,the latest machine learning models(LightGBM,CatBoost,TabNet,and NODE)were used to make predictions with tabular features,and the best coefficient of determination R^(2)values obtained for TSC-P,TSC-C and TSC-Temp predictions were 0.435(LightGBM),0.857(Cat-Boost)and 0.678(LightGBM),respectively,which were higher than those of classic models(backpropagation and support vector machine).Then,making predictions was performed by using SOTA time series regression models(SCINet,DLinear,Informer,and MLSTM-FCN)with original time series,SOTA image regression models(NesT,CaiT,ResNeXt,and GoogLeNet)with resized time series,and the proposed Concatenate-Model and Parallel-Model with both tabular features and time *** optimization and comparisons,it was finally determined that the Concatenate-Model with MLSTM-FCN,SCINet and Informer as feature extractors performed the best,and its R^(2)values for predicting TSC-P,TSC-C and TSC-Temp reached 0.470,0.858 and 0.710,*** field test accuracies for TSC-P,TSC-C and TSC-Temp were 0.459,0.850 and 0.685,respectively.A related importance analysis was carri

关键词： BOF steelmaking In-blow prediction TSC test Machine learning Deep learning Field application

Boson star superradiance

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 69-78页

作者： He-Yu Gao Paul M.Saffin Yi-jie Wang Qi-Xin xie Shuang-Yong Zhou School of Physical Sciences University of Science and Technology of ChinaHefei 230026China School of Physics and Astronomy University of NottinghamUniversity ParkNottingham NG72RDUK Interdisciplinary Center for Theoretical Study University of Science and Technology of ChinaHefei 230026China Peng Huanwu Center for Fundamental Theory Hefei 230026China

Recently,it has been realized that in some systems internal space rotation can induce energy amplification for scattered waves,similar to rotation in real *** particularly,it has been shown that energy extraction is possible for a Q-ball,a stationary non-topological soliton that is coherently rotating in its field *** this paper,we generalize the analysis to the case of boson stars,and show that the same energy extraction mechanism still works for boson stars.

关键词： superradiance boson star field space rotation

Biomimetic porous silicon oxycarbide ceramics with improved specific strength and efficient thermal insulation

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Journal of Materials Science & Technology 2024年第1期168卷 185-193页

作者： Zhuoqing Zhang Jinghan Li Lei Cao Yu shi Huajie Yang Rui Yang Fan xie Xing Zhang shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159China Shenyang Aircraft Design and Research Institute Shenyang 110035China

Considering the challenge of aerodynamic heating,the development of high-performance insulating ce-ramic materials with lightweight and low thermal conductivity is crucially important for aerospace vehi-cles to achieve flight at high speed for a long *** this work,macro-porous silicon oxycarbide(SiOC)ceramics with directional pores(DP-SiOC)(mean pore size of 88.1μm)were prepared using polysiloxane precursors via freeze casting and photocrosslinking,followed by *** DP-SiOC samples were lightweight(density∼0.135 g cm^(-3))with a porosity of 90.4%,which showed good shapability through the molding of polysiloxane *** DP-SiOC samples also exhibited an ultra-low thermal con-ductivity of 0.048 W(m K)^(-1)at room temperature,which can also withstand heat treatment at 1200°C for 1 *** addition,scaffolds with triply periodic minimal surfaces(TPMS)were fabricated using digital light processing(DLP)printing,which was further filled with polysiloxane precursors for increasing the strength of *** TPMS scaffolds filled with macro-porous SiOC ceramics(TPMS-DP-SiOC)showed good integration between TPMS and macro-pore structures,which had a porosity∼75%and high specific strength of 9.73×10^(3)N m kg^(-1).The thermal conductivity of TPMS-DP-SiOC samples was 0.255 W(m K)^(-1)at room *** biomimetic TPMS-DP-SiOC ceramics developed in this study are likely used for thermal protection systems.

关键词： Thermal insulation Light weight Macro-porous ceramics SiOC

Nanofluidic memristor based on the elastic deformation of nanopores with nanoparticle adsorption

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National Science Review 2024年第04期11卷 46-54页

作者： Xi Zhou Yuanyuan Zong Yongchang Wang Miao Sun Deli shi Wei Wang Guanghua Du Yanbo xie Department of Chemistry and Chemical Engineering Northwestern Polytechnical University School of Physical Science and Technology Northwestern Polytechnical University School of Aeronautics and Institute of Extreme Mechanics Northwestern Polytechnical University Institute of Modern Physics Chinese Academy of Sciences

The memristor is the building block of neuromorphic computing. We report a new type of nanofluidic memristor based on the principle of elastic strain on polymer nanopores. With nanoparticles absorbed at the wall of a single conical polymer nanopore, we find a pinched hysteresis of the current within a scanning frequency range of 0.01–0.1 Hz, switching to a diode below 0.01 Hz and a resistor above 0.1 Hz. We attribute the current hysteresis to the elastic strain at the tip side of the nanopore, caused by electrical force on the particles adsorbed at the inner wall surface. Our simulation and analytical equations match well with experimental results, with a phase diagram for predicting the system transitions. We demonstrate the plasticity of our nanofluidic memristor to be similar to a biological synapse. Our findings pave a new way for ionic neuromorphic computing using nanofluidic memristors.

关键词： nanofluidics memristor neurocomputing elastic deformation

A resonant high-pressure microsensor based on a composite pressure-sensitive mechanism of diaphragm bending and volume compression

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Microsystems & Nanoengineering 2024年第2期10卷 57-66页

作者： Pan Qian Zongze Yu jie Yu Yulan Lu Bo xie Jian Chen Deyong Chen Junbo Wang The State Key Laboratory of Transducer Technology Aerospace Information Research InstituteChinese Academy of SciencesBeijing100190China The School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing100049China

In this paper,a composite pressure-sensitive mechanism combining diaphragm bending and volume compression was developed for resonant pressure microsensors to achieve high-pressure measurements with excellent *** composite mechanism was explained,and the sensor structure was designed based on theoretical analysis and finite element *** all-silicon resonant high-pressure microsensor with multiple miniaturized cavities and dual resonators was developed,where dual resonators positioned in two resonant cavities with suitably different widths are used to perform opposite characteristics in pressure and the same characteristics at different temperatures,which can improve pressure sensitivities and realize temperature self-compensation by differential frequency *** microsensor was fabricated by microfabrication,and the experimental results showed that the sensor had an accuracy of±0.015%full scale(FS)in a pressure range of 0.1~100 MPa and a temperature range of−10~50℃.The pressure sensitivity of the differential frequency was 261.10 Hz/MPa(~2523 ppm/MPa)at a temperature of 20℃,and the temperature sensitivities of the dual resonators were−1.54 Hz/℃(~−14.5 ppm/℃)and−1.57 Hz/℃(~−15.6 ppm/℃)at a pressure of 2 *** differential output had an outstanding stability within±0.02 Hz under constant temperature and ***,this research provides a convenient solution for high-pressure measurements because of its advantages,namely,large range,excellent accuracy and stability.

关键词： stability resonant bending