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Chinese Chemical Letters 2016年第3期27卷 417-422页

作者： Bo Li Xu-zhuo sun College of Chemistry and Chemical Engineering Henan University of Technology

Two new supramolecular architectures {（HC2O4）2^2- [C6H（18）N2^2＋ C（36）H（36）N（24）O（12）]} 12H2O（1） and{（C6H5SO3）22 [C6H（18）N22＋ C（36）H（36）N（24）O（12）]} 12H2O（2） were synthesized and characterized by singlecrystal X-ray diffraction, thermogravimetric analysis and X-ray powder diffraction. Compound 1contains infinite two dimensional（2D） L18（8）14（8）8（4） type anion–water aggregates [（HC2O4）4（H2O）（22）]^4- and results in the construction of sandwich-like three dimensional（3D） networks. In compound 2, honeycomb-like three dimensional（3D） networks are fabricated by one dimensional（1D）＂W＂-like T5（0）A2 type anion–water clusters [（C6H5SO3）（H2O）6]^-. These results indicate that anionic groups play a crucial role in modulating the structures of water clusters with their spatial structure and binding sites. In these two structures, the majority of interactions are O...H and H...H interactions on the Hirshfeld surface, which means that hydrogen bonding and hydrophobic interactions are the dominate drive forces in forming these supramolecular systems.

关键词： Cucurbituril Supramolecular Water clusters Anion templates Pseudorotaxane

Multi model forecast biases of the diurnal variations of intense rainfall in the Beijing-Tianjin-Hebei region

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Science China Earth Sciences 2022年第8期65卷 1490-1509页

作者： Qi ZHONG zhuo sun Haoming CHEN Jiangbo LI Lili SHEN China Meteorological Administration Training Center Beijing100081China Hebei Meteorological Observatory Shijiazhuang050020China Chinese Academy of Meteorological Sciences Beijing100081China

Forecasts of the intense rainfall events are important for the disaster prevention and reduction in the Beijing-TianjinHebei region(BTHR). What are the common biases in the forecasts of intense rainfall in the current operational numerical models? What are the possible causes of model bias? In this study, intense rainfall events in the BTHR were categorized into two types: those mainly due to strong synoptic forcings(SSF) and those with weak synoptic forcings(WSF). The results showed that,the numerical forecasts tend to overestimate the frequency of intense rainfall events but underestimate the rainfall intensity. Of these, the overestimation of precipitation frequency mainly appeared in the mountainous areas in the afternoon. Compared with global models, high-resolution mesoscale models showed a notable improvement in forecasting the afternoon intense rainfall,while they all have an obvious bias in forecasting the nighttime rainfall. For the WSF type, both global model and mesoscale model have a low forecast skill, with large biases in subdaily propagation feature. The possible causes are related to a poor performance of the model in reproducing the local thermodynamical circulations and the dynamical processes in the planetary boundary layer. So, the biases in forecasting the WSF type intense rainfall showed notable features of nonlinearity, which made it really challenging to understand their physical processes and to improve the associated forecasts.

关键词： The Beijing-Tianjin-Hebei region Diurnal variations of precipitation Operational numerical forecast Bias feature Local circulations

Two Types of Compact UHF Antennas for Partial Discharge Measurement

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高电压技术 2008年第11期34卷 2305-2310页

作者： JIN zhuo-rui sun Cai-xin CHENG Chang-kui LI Jian State Key Laboratory of Power Transmission Equipment ＆ System Security and New Technology Department of High Voltage and Insulation Engineering Chongqing University Chongqing 400044 China

To investigate the partial discharge (PD) online monitoring of transformers by ultra-high-frequency (UHF) approaches,high-qualified UHF antennas are focused on as one key technique. The size of UHF sensor used for PD UHF online monitoring in transformer is excessively large,therefore,it is not convenient for internal installation of transformer. Two types of compact UHF antennas with small sizes,a Hilbert fractal antenna and a small loop antenna are presented. PD experiments of three typically artificial insulation defects are executed and both antennas are used for PD measurement. The spectra of power via frequency of detected PD signals are analyzed and compared. The experimental results show that the Hilbert fractal antenna and small loop antenna are qualified for PD online UHF monitoring.

关键词：超高频天线局部放电测量方法电压

Machine Learning-Based Temperature and Wind Forecasts in the Zhangjiakou Competition Zone during the Beijing 2022 Winter Olympic Games

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Journal of Meteorological Research 2024年第4期38卷 664-679页

作者： zhuo sun Jiangbo LI Ruiqiang GUO Yiran ZHANG Gang ZHU Xiaoliang YANG China Meteorological Administration Xiong'an Atmospheric Boundary Layer Key Laboratory Xiong'an New Area 071800 Hebei Key Laboratory of Meteorology and Ecological Environment Shijiazhuang 050021 Hebei Meteorological Observatory Shijiazhuang 050021 College of Computer and Cyber Security Hebei Normal UniversityShijiazhuang 050024

Weather forecasting for the Zhangjiakou competition zone of the Beijing 2022 Winter Olympic Games is a challenging task due to its complex *** weather prediction models generally perform poorly for cold air pools and winds over complex terrains,due to their low spatiotemporal resolution and limitations in the description of dynamics,thermodynamics,and microphysics in mountainous *** study proposes an ensemble-learning model,named ENSL,for surface temperature and wind forecasts at the venues of the Zhangjiakou competition zone,by integrating five individual models—linear regression,random forest,gradient boosting decision tree,support vector machine,and artificial neural network(ANN),with a ridge regression as meta *** ENSL employs predictors from the high-resolution ECMWF model forecast(ECMWF-HRES) data and topography data,and targets from automatic weather station *** categories of predictors(synoptic-pattern related fields,surface element fields,terrain,and temporal features) are fed into *** results demonstrate that ENSL achieves better performance and generalization than individual *** root-mean-square error(RMSE) for the temperature and wind speed predictions is reduced by 48.2% and 28.5%,respectively,relative to *** the gust speed,the performance of ENSL is consistent with ANN(best individual model) in the whole dataset,whereas ENSL outperforms on extreme gust samples(42.7% compared with 38.7% obtained by ECMWF-HRES in terms of RMSE reduction).Sensitivity analysis of predictors in the four categories shows that ENSL fits their feature importance rankings and physical explanations effectively.

关键词： machine learning ensemble learning post-processing cold air pools mountain Beijing 2022 Winter Olympic Games

Efficiency Enhancement of Inverted Polymer Solar Cells Using Ionic Liquid-functionalized Carbon Nanoparticles-modified ZnO as Electron Selective Layer

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Nano-Micro Letters 2014年第1期6卷 24-29页

作者： Feng Zhu Xiaohong Chen Zhe Lu Jiaxiang Yang Sumei Huang zhuo sun Engineering Research Center for Nanophotonics and Advanced Instrument Ministry of Educationand Department of PhysicsEast China Normal University Department of Chemistry Anhui University

ZnO thin film was fabricated on tin-doped indium oxide electrode as an electron selective layer of inverted polymer solar cells using magnetron sputtering deposition. Ionic liquid-functionalized carbon nanoparticles(ILCNs) film was further deposited onto ZnO surfaces by drop-casting ILCNs solution to improve interface properties. The power conversion efficiency(PCE) of inverted polymer solar cells(PSCs)with only ZnO layer was quickly decreased from 2.7% to 2.2% when the thickness of ZnO layer was increased from 15 nm to 60 nm. However, the average PCE of inverted PSCs with ZnO layer modified with ILCNs only decreased from 3.5% to 3.4%, which is comparable to that of traditional PSCs with poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) anode buffer layer. The results suggested that the contact barrier between ZnO layer and poly(3-hexylthiophene) and phenyl-C61-butyric acid methylester(P3HT:PCBM)blended film compared to ZnO bulk resistance can more significantly influence the performance of inverted PSCs with sputtered ZnO layer. The vanishment of negative capacitive behavior of inverted PSCs with ILCNs modified ZnO layer indicated ILCNs can greatly decrease the contact barrier of ZnO/P3HT:PCBM interface.

关键词： Polymer Solar cell ZnO

Fabrication and Evaluation of Low-cost Cu_2ZnSn(S,Se)_4 Counter Electrodes for Dyesensitized Solar Cells

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Nano-Micro Letters 2013年第4期5卷 281-288页

作者： Jie Shen Dingwen Zhang Junjie Li Xiaodong Li zhuo sun Sumei Huang Engineering Research Center for Nanophotonics & Advanced Instrument Ministry of Education Department of Physics East China Normal University Advanced Materials Technology Centre Singapore Polytechnic

We explore a simple and eco-friendly approach for preparing CZTS powders and a screen-printing process for Cu_2ZnSn(S,Se)_4(CZTSSe) counter electrodes(CEs) in dye-sensitized solar cells(DSCs). Cu_2ZnSnS_4(CZTS) nanoparticles have been synthesized via a hydrazine-free solvothermal approach without the assistance of organic ligands. CZTS has been prepared by directly drop-casting the CZTS ink on the cleaned FTO glass, while CZTSSe CEs have been fabricated by screen-printing CZTS pastes, followed by post selenization using Se vapor obtained from elemental Se pellets. The crystal structure, composition and morphology of the as-deposited CZTS nanoparticles and CZTSSe electrodes are characterized by X-ray diffractometer, energy dispersive spectrometer, field emission scanning electron microscopy and transmission electron *** electrochemical properties of CZTS, CZTSSe and Pt CE based DSCs are examined and analyzed by electrochemical impedance spectroscopy. The prepared CZTS and CZTSSe CEs exhibit a cellular structure with high porosity. DSCs fabricated with CZTSSe CEs achieve a power conversion efficiency of 5.75% under AM 1.5 G illumination with an intensity of 100 m W/cm^2, which is higher than that(3.22%) of the cell using the CZTS CE. The results demonstrate that the CZTSSe CE possesses good electrocatalytic activity for the reduction of charge carriers in electrolyte. The comprehensive CZTSSe CE process is cheap and scalable. It can make large-scale electro-catalytic film fabrication cost competitive for both energy harvesting and storage applications.

关键词： Copper-zinc-tin-chalcogenide Selenization Counter electrode Dye-sensitized solar cells

Hydrothermal Synthesis, Characterization and Catalytic Properties of Nanoporous MoO_ 3/ZrO_ 2 Mixed Oxide

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Chemical Research in Chinese Universities 2006年第3期22卷 364-367页

作者： SHI Wei LIU Hai-yan REN Dong-mei MA zhuo sun Wen-dong Faculty of Chemistry Northeast Normal University Changchun 130024 P. R. China

A nanoporous MoO3/ZrO2 mixed oxide was hydrothermally synthesized by hydrolyzing zirconium isopropoxide in the presence of a cationic surfactant, eetyltrimethylammonium bromide（CTAB）. The crystal structure and the acidity of the obtained nanoporous MoO3/ZrO2 mixed oxide were determined by means of XRD, N2 adsorption-desorption and NH3-TPD, respectively. The isobutane/butene alkylation over the MoO3/ZrO2 catalyst was carried out in a fixed bed reactor. The results reveal that ZrO2 in MoO3/ZrO2 exists mainly in the tetragonal phase, and the catalyst samples possess large specific surface areas as well as moderate acidity for isobutane/butene alkylation. Compared with samples prepared by impregnation and sol-gel processes, MoO3/ZrO2 mixed oxide samples prepared in this work have a better catalytic activity.

关键词： MoO3/ZrO2 Hydrothermal synthesis Solid acid catalyst Alkylation

Data fusion and machine learning for ship fuel efficiency modeling:Part Ⅱ-Voyage report data,AIS data and meteorological data

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Communications in Transportation Research 2022年第1期2卷 222-243页

作者： Yuquan Du Yanyu Chen Xiaohe Li Alessandro Schonborn zhuo sun Centre for Maritime and Logistics Management Australian Maritime CollegeUniversity of TasmaniaLauncestonTAS 7250Australia Institute for Marine and Antarctic Studies College of Sciences and EngineeringUniversity of TasmaniaTaroonaTAS 7053Australia College of Power and Energy Engineering Harbin Engineering UniversityHarbin150001China Maritime Energy Management World Maritime UniversityFiskehamnsgatan 120124 MalmoSweden College of Transportation Engineering Dalian Maritime UniversityDalian116026China

When voyage report data is utilized as the main data source for ship fuel efficiency analysis,its information on weather and sea conditions is often regarded as *** solve this issue,this study approaches AIS data to obtain the ship's actual detailed geographical positions along its sailing trajectory and then further retrieve the weather and sea condition information from publicly accessible meteorological data *** more reliable data about weather and sea conditions the ship sails through is fused into voyage report data in order to improve the accuracy of ship fuel consumption rate *** 8100-TEU to 14,000-TEU containerships from a global shipping company were used in *** each ship,nine datasets were constructed based on data fusion and eleven widely-adopted machine learning models were *** results revealed the benefits of fusing voyage report data,AIS data,and meteorological data in improving the fit performances of machine learning models of forecasting ship fuel consumption *** the best datasets,the performances of several decision tree-based models are promising,including Extremely randomized trees(ET),AdaBoost(AB),Gradient Tree Boosting(GB)and XGBoost(XG).With the best datasets,their R^(2) values over the training sets are all above 0.96 and mostly reach the level of 0.99-1.00,while their R^(2) values over the test sets are in the range from 0.75 to *** errors of ET,AB,GB,and XG on daily bunker fuel consumption,measured by RMSE and MAE,are usually between 0.8 and 4.5 ton/*** results are slightly better than our previous study,which confirms the benefits of adopting the actual geographical positions of the ship recorded by AIS data,compared with the estimated geographical positions derived from the great circle route,in retrieving weather and sea conditions the ship sails through.

关键词： Ship fuel efficiency Fuel consumption rate Voyage report AIS Data fusion Machine learning

Effective Improvement of the Photovoltaic Performance of Carbon-Based Perovskite Solar Cells by Additional Solvents

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Nano-Micro Letters 2016年第4期8卷 347-357页

作者： Chenxi Zhang Yudan Luo Xiaohong Chen Yiwei Chen zhuo sun Sumei Huang Engineering Research Center for Nanophotonics & Advanced Instrument Ministry of EducationDepartment of PhysicsEast China Normal University

A solvent-assisted methodology has been developed to synthesize CH_3NH_3 PbI_3perovskite absorber *** involved the use of a mixed solvent of CH_3NH_3 I,PbI_2,c-butyrolactone,and dimethyl sulfoxide(DMSO) followed by the addition of chlorobenzene(CB).The method produced ultra-flat and dense perovskite capping layers atop mesoporous TiO_2 films,enabling a remarkable improvement in the performance of free hole transport material(HTM) carbon electrode-based perovskite solar cells(PSCs).Toluene(TO) was also studied as an additional solvent for *** the annealing temperature of 100 °C,the fabricated HTM-free PSCs based on drop-casting CB demonstrated power conversion efficiency(PCE) of 9.73 %,which is 36 and 71 % higher than those fabricated from the perovskite films using TO or without adding an extra solvent,*** interaction between the PbI_2–DMSO–CH_3NH_3I intermediate phase and the additional solvent was ***,the influence of the annealing temperature on the absorber film formation,morphology,and crystalline structure was investigated and correlated with the photovoltaic *** efficient,simple,and stable HTM-free solar cells with a PCE of 11.44 % were prepared utilizing the optimum perovskite absorbers annealed at 120 °C.

关键词： Halide perovskite Solar cell Spin-coating Carbon counter electrode Free hole transporting material

Progress in in vitro culture and gene editing of porcine spermatogonial stem cells

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Zoological Research 2019年第5期40卷 343-348页

作者： Yi-zhuo sun Si-Tong Liu Xiao-Meng Li Kang Zou Germline Stem Cells and Microenvironment Lab College of Animal Science and Technology Nanjing Agricultural University Nanjing Jiangsu 210095 China College of Life Sciences Jilin University Changchun Jilin 130012 China Key Laboratory of Molecular Epigenetics of MOE Institute of Genetics and Cytology Northeast Normal University Changchun Jilin 130024 China

Research on in vitro culture and gene editing of domestic spermatogonial stem cells (SSCs) is of considerable interest but remains a challenging issue in animal science. In recent years, some progress on the isolation, purification, and genetic manipulation of porcine SSCs has been reported. Here, we summarize the characteristics of porcine SSCs as well current advances in their in vitro culture, potential usage, and genetic manipulation. Furthermore, we discuss the current application of gene editing in pig cloning technology. Collectively, this commentary aims to summarize the progress made and obstacles encountered in porcine SSC research to better serve animal husbandry, improve livestock fecundity, and enhance potential clinical use.

关键词： Progress vitro culture stem cells