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Impact of Initial Soil Conditions on Soil Hydrothermal and Surface Energy Fluxes in the Permafrost Region of the Tibetan Plateau

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Advances in Atmospheric Sciences 2024年第4期41卷 717-736页

作者： Siqiong LUO Zihang CHEN jingyuan WANG Tonghua WU Yao XIAO Yongping QIAO Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Cryosphere Research Station on the Qinghai-Tibet Plateau State Key Laboratory of Cryospheric ScienceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Accurate initial soil conditions play a crucial role in simulating soil hydrothermal and surface energy fluxes in land surface process *** study emphasized the influence of the initial soil temperature(ST)and soil moisture(SM)conditions on a land surface energy and water simulation in the permafrost region in the Tibetan Plateau(TP)using the Community Land Model version 5.0(CLM5.0).The results indicate that the default initial schemes for ST and SM in CLM5.0 were simplistic,and inaccurately represented the soil characteristics of permafrost in the TP which led to underestimating ST during the freezing period while overestimating ST and underestimating SLW during the thawing period at the XDT *** the long-term spin-up method to obtain initial soil conditions has only led to limited improvement in simulating soil hydrothermal and surface energy *** modified initial soil schemes proposed in this study comprehensively incorporate the characteristics of permafrost,which coexists with soil liquid water(SLW),and soil ice(SI)when the ST is below freezing temperature,effectively enhancing the accuracy of the simulated soil hydrothermal and surface energy ***,the modified initial soil schemes greatly improved upon the results achieved through the long-term spin-up *** modified initial soil schemes experiments resulted in a 64%,88%,and 77%reduction in the average mean bias error(MBE)of ST,and a 13%,21%,and 19%reduction in the average root-mean-square error(RMSE)of SLW compared to the default simulation ***,the average MBE of net radiation was reduced by 7%,22%,and 21%.

关键词： initial soil conditions soil temperature soil liquid water soil ice surface energy fluxes permafrost

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Science communication with science fiction movies

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The Innovation 2024年第2期5卷 17-18页

作者： Yuanzhuo Wang jingyuan Li Yuanhao Cui Department of Computer Science Beijing Technology and Business UniversityNo.33 Fucheng RoadHaidianBeijing 100048China Institute of Computing Technology Chinese Academy of SciencesNo.6 Kexueyuan South RoadHaidianBeijing 100190China School of System Design and Intelligent Manufacturing Southern University of Science and TechnologyNo.1088 Xueyuan AvenueShenzhenGuangdong 518055China

“It is not as easy as it looks,”Holden Thorp,Science’s chief editor,commented at the end of 2021,when explaining new research findings of the COVID-19 pandemic to the public had encountered great difficulties.1 As a matter of fact,science communication has never been easy because serious scientific knowledge is prone to be boring rather than *** is only one atypical medium for science communication,i.e.,the science fiction movie(sci-fi movie for short),that has a huge amount of fans.

关键词： communication editor movie

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Phosphafluorenyl lithiums:direct synthesis from white phosphorus,structure and diversified synthons

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Science China Chemistry 2022年第2期65卷 322-327页

作者： jingyuan Hu Zhengqi Chai Wei Liu Zhe Huang Junnian Wei Wen-Xiong Zhang Beijing National Laboratory for Molecular Sciences(BNLMS) State Key Laboratory of Rare Earth Materials Chemistry and Applications&Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of ChemistryPeking UniversityBeijing 100871China

While rich chemistry of phospholyl anions is discovered,phosphafluorenyl anions are only proposed as the critical intermediates for the synthesis of *** this article,we reported the direct synthesis of phosphafluorenyl lithiums from white phosphorus(P_(4))through direct P-C bond *** reaction between P4 and biphenyl dilithio reagents efficiently afforded phosphafluorenyl lithiums,which were further used to synthesize different kinds of organophosphorus *** aggregation states of phosphafluorenyl lithiums were investigated for the first *** studies by DFT calculations revealed a cooperative nucleophilic attack of two C−Li bonds on P_(4)molecule.

关键词： white phosphorus organophosphorus compounds P–C bond formation P_(4)functionalization phosphafluorenyl lithium

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Controlling molecular assembly on time scale:Time-dependent multicolor fluorescence for information encryption

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Chinese Chemical Letters 2024年第7期35卷 336-340页

作者： Zixi Zou jingyuan Wang Yian Sun Qian Wang Da-Hui Qu Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Dynamic assembly on time scale is common in biological systems but rare for artificial materials,especially for smart luminescent *** molecular assembly in a spatio-temporal manner and resulting in white-light-including multicolor fluorescence with time-dynamic features remains ***,controlling molecular assembly on time scale is achieved by integrating a pH-responsive motif to a transient alkaline solution which is fabricated by activators(NaOH)and deactivators(esters),leading to automatic assembly on time scale and time-dependent multicolor fluorescence changing from blue to white and *** kinetics of the assembly process is dependent on the ester hydrolysis process,which can be controlled by varying ester concentrations,temperature,initial pH,stirring rate and ester *** dynamic fluorescent system can be further developed for intelligent fluorescent materials such as fluorescent ink,three-dimension(3D)codes and even four-dimension(4D)codes,exhibiting a promising potential for information encryption.

关键词： Supramolecular chemistry Multicolor fluorescence White light emission Time-dependent fluorescence Information encryption

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Modeling and analysis of porosity and compressive strength of gradient Al_2O_3-ZrO_2 ceramic lter using BP neural network

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China Foundry 2013年第4期10卷 227-231页

作者： Li Qiang Zhang Fengfeng Yu jingyuan Tang Ji School of Materials Science and Engineering Liaoning University of Technology Shenyang Research Institute of Foundry

BP neural network was used in this study to model the porosity and the compressive strength of a gradient Al2Q-ZrO2 ceramic foam filter prepared by centrifugal slip casting. The influences of the load applied on the epispastic polystyrene template （F）, the centrifugal acceleration （V） and sintering temperature （T） on the porosity （P） and compressive strength （a） of the sintered products were studied by using the registered three-layer BP model. The accuracy of the model was verified by comparing the BP model predicted results with the experimental ones. Results show that the model prediction agrees with the experimental data within a reasonable experimental error, indicating that the three-layer BP network based modeling is effective in predicting both the properties and processing parameters in designing the gradient Al203-ZrO2 ceramic foam filter. The prediction results show that the porosity percentage increases and compressive strength decreases with an increase in the applied load on epispastic polystyrene template. As for the influence of sintering temperature, the porosity percentage decreases monotonically with an increase in sintering temperature, yet the compressive strength first increases and then decreases slightly in a given temperature range. Furthermore, the porosity percentage changes little but the compressive strength first increases and then decreases when the centrifugal acceleration increases.

关键词： gradient Al203-ZrO2 ceramic foams centrifugal process parameters BP neural network porosity compressive strength

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Noninvasive genetic assessment of the population trend and sex ratio of the Shennongjia population of Sichuan snub-nosed monkeys(Rhinopithecus roxellana)

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Chinese Science Bulletin 2012年第10期57卷 1135-1141页

作者： CHANG ZongFei LIU ZhiJin YANG jingyuan LIMing VIGILANT Linda Key Laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China Department of Primatology Max Planck Institute for Evolutionary Anthropology Leipzig 04103 Germany Graduate University of the Chinese Academy of Sciences Beijing 100039 China Hubei Province Key Laboratory of Conservation Biology of Shennongjia Golden Monkey Muyu 44241l China

Effective population management relies on assessments of population size and sex ***,these estimates are difficult to obtain for elusive and rare ***,noninvasive genetic census methods have been developed as an alternative to tradi-tional capture-mark-recapture *** this study,we estimated the size of the Sichuan snub-nosed monkey(Rhinopithecus roxellana) population in the Shennongjia Nature Reserve(SNR) using a noninvasive sampling method based on 16 microsatellite *** also used a PCR-based genetic method to sex the sampled individuals and infer the population sex *** population size of *** in the SNR was estimated to be 1044 individuals(95% CITIRM:613-1409) .The estimated population sex ratio is more female-biased than expected,which we attribute to the sampling biased towards one male units and limited sampling of bachelor male ***,there is no suggestion that the heavy traffic road through the reserve might block movement of *** results of this study indicate genetic assessments based on a noninvasive sampling method can provide useful in-formation regarding populations of elusive primates.

关键词：神农架自然保护区人口规模川金丝猴性别比例遗传评估侵入性信噪比估计抽样方法

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Synchronously Improving the Thermal Conductivity and Mechanical Properties of Al–Si–Fe–Mg–Cu–Zn Alloy Die Castings Through Ultrasonic-Assisted Rheoforming

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Acta Metallurgica Sinica(English Letters) 2021年第10期34卷 1331-1344页

作者： Mingfan Qi Yonglin Kang jingyuan Li Yuzhao Xu Jicheng Wang Gunan Li Aisen Liu Beijing Advanced Innovation Center for Materials genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China Zhuhai Runxingtai Electric Co. LtdZhuhai 591000China Center International Group Co. LtdBeijing 100176China

An ultrasonic vibration-assisted air-cooled stirring rod process(ACSR+UV)was used to efficiently prepare a large-volume semisolid slurry with a mass of more than 40 kg.A low-cost Al–Si–Fe–Mg–Cu–Zn die-casted alloy with high thermal conductivity,high plasticity and medium strength was *** alloy was used to manufacture large,thin-walled parts for 5 G base stations by using the ACSR+UV rheological die-casting(ACSR+UV R-DC)*** were performed on the microstructure,porosity,mechanical properties,fracture behaviour and thermal conductivity of the ACSR+UV R-DC alloy,which was then compared to traditionally die-casted(T-DC)and ACSR R-DC *** mechanisms for the microstructural refinement and enhancement of the mechanical and thermal conductivity performances of the ACSR+UV R-DC alloy were also *** results showed that the ACSR+UV process increased the nucleation rate of the melt due to the increase in the nucleation area and the generation of cavitation bubbles.A radial-and an axial-forced convection was also generated inside the melt under the combined effects of acoustic flow and mechanical stirring,thereby homogenising the melt composition field and the temperature ***,the ACSR+UV R-DC process not only refined the primaryα-Al(α_(1)-Al),the eutectic silicon and the secondaryα-Al(α_(2)-Al),but also greatly improved the morphology and the distribution of the β-Al5FeSi *** mechanical properties of the ACSR+UV R-DC alloy were higher than those of the T-DC and the ACSR R-DC *** to the T-DC alloy,the ultimate tensile strength,elongation and yield strength of the ACSR+UV R-DC alloy were increased by 34%,122%and 19%,*** was because the ACSR+UV R-DC technique gave the alloy the characteristics of high density,fine sphericalα1-Al grain and a fine and uniform β-phase,which improved the fracture behaviour of the *** thermal conductivity of the ACSR+UV R-DC alloy was 184 W/(m K),which was 10.2%a

关键词： Rheological die-casting Ultrasonic vibration Al–Si–Fe–Mg–Cu–Zn alloy Mechanical properties Thermal conductivity

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Non-destructive corrosion study on a magnesium alloy with mechanical properties tailored for biodegradable cardiovascular stent applications

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Journal of Materials Science & Technology 2021年第7期66卷 128-138页

作者： Changhong Cai Marta M.Alves Renbo Song Yongjin Wang jingyuan Li School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Centro de Qufmica Estrutural Instituto Superior TecnicoUniversidade de LisboaAv.Rovisco Pais1049-001LisboaPortugal

AnMg-2Zn-0.6Zr-0.6Nd alloy for biodegradable cardiovascular stent applications was prepared through indirect extrusion. The alloy exhibited a superior combination of tensile yield strength(TYS), ultimate tensile strength(UTS) and elongation(EL) of about 269 MPa, 298 MPa and 25.6 %, respectively. In addition,the non-destructive electrochemical frequency modulation(EFM) technique was used for the first time to investigate the corrosion behavior of Mg alloys combined with electrochemical impedance spectroscopy(EIS) in Dulbecco’s Modified Eagle’s Medium(DMEM) and in Hank’s solution. Compared with the corrosion rate of 0.07 mm/year in Hank’s solution, lower corrosion rate of 0.03 mm/year was achieved in DMEM. The significant differences between the corrosion rate trends were discussed and related with the composition of the corrosion layer formed. Depending on the biomimetic fluids tested, different corrosion products were precipitated on the alloy’s surface: a compact and homogeneous layer of Mg_(x)Ca_(y)(PO_(4))_(z) and Zn(OH)_(2) and organic compounds was formed in DMEM, whereas a partial coverage of Mg_(x)Ca_(y)(PO_(4))_(z) and Zn(OH)_(2) was formed in Hank’s solution.

关键词： Mg-Zn-Zr-Nd alloy Mechanical property Corrosion EIS EFM

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Predicting model on ultimate compressive strength of Al_2O_3-ZrO_2 ceramic foam filter based on BP neural network

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China Foundry 2011年第3期8卷 286-289页

作者： Yu jingyuan Li Qiang Tang Ji Sun Xudong College of Materials Science and Engineering Liaoning University of Technology Jinzhou 121001 China Key Laboratory of New Materials in Automobile of Liaoning Province Liaoning University of Technology Jinzhou 121001 China Shenyang Research Institute of Foundry Shenyang 110022 China Key Laboratory for Anisotropy and Texture of Materials Ministry of Education Northeastern University Shenyang 110004 China

In present study, BP neural network model was proposed for the prediction of ultimate compressive strength of Al2O3-ZrO2 ceramic foam filter prepared by centrifugal slip casting. The inputs of the BP neural network model were the applied load on the epispastic polystyrene template （F）, centrifugal acceleration （v） and sintering temperature （T）, while the only output was the ultimate compressive strength （（7）. According to the registered BP model, the effects of F, v, T on 0 were analyzed. The predicted results agree with the actual data within reasonable experimental error, indicating that the BP model is practically a very useful tool in property prediction and process parameter design of the Al2O3-ZrO2 ceramic foam filter prepared by centrifugal slip casting.

关键词： Al2O3-ZrO2 ceramic foam centrifugal slip casting BP neural network process parameters ultimate compressive strength

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Combining reinforcement learning with mathematical programming:An approach for optimal design of heat exchanger networks

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Chinese Journal of Chemical Engineering 2024年第5期69卷 63-71页

作者： Hui Tan Xiaodong Hong Zuwei Liao jingyuan Sun Yao Yang Jingdai Wang Yongrong Yang State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 311215China

Heat integration is important for energy-saving in the process *** is linked to the persistently challenging task of optimal design of heat exchanger networks(HEN).Due to the inherent highly nonconvex nonlinear and combinatorial nature of the HEN problem,it is not easy to find solutions of high quality for large-scale *** reinforcement learning(RL)method,which learns strategies through ongoing exploration and exploitation,reveals advantages in such ***,due to the complexity of the HEN design problem,the RL method for HEN should be dedicated and designed.A hybrid strategy combining RL with mathematical programming is proposed to take better advantage of both *** insightful state representation of the HEN structure as well as a customized reward function is introduced.A Q-learning algorithm is applied to update the HEN structure using theε-greedy *** results are obtained from three literature cases of different scales.

关键词： Heat exchanger network Reinforcement learning Mathematical programming Process design

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