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Science China(Technological Sciences) 2024年第2期67卷 558-567页

作者： SHI WeiLin ZHOU jian LU HaiBao ELMARAKBI Ahmed fu yong-Qing National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080China College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China Faculty of Engineering and Environment University of NorthumbriaNewcastle upon Tyne NEI 8STUK

Network structures of various polymers have significant effects on their mechanical properties;therefore,numerous studies have investigated the constitutive relationship between symmetrical network structures and their rubber elasticity in ***,few studies have focused on asymmetrical network structures in polymers that undergo bond exchange reactions,selfassembly,or mechanochemical coupling—all of which are induced by transition probabilities of chemical bonding *** this study,an extended constraint junction and phantom network model is formulated using the tree-growing theory to establish a constitutive relationship between asymmetrical network structures and their rubber elasticity in polymers.A free-energy equation is further developed to explore working principles of configurational transitions on the dynamic rubber elasticity of symmetrical and asymmetrical network *** constitutive relationship between dynamic rubber elasticity and symmetrical and asymmetrical network structures has also been proposed for the gels undergoing mechanochemical and hydromechanical ***,the effectiveness of this newly proposed tree-growing model has been verified by comparing with the classical affine network model,finite element analysis,and the experimental results of gels reported in literature.

关键词： gel polymer network rubber elasticity asymmetric

Research of green cement clinker calcinated from ferrochrome slag

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Journal of Environmental Sciences 1999年第4期11卷 403-406页

作者： LIU Xiao-bo fu yong-jian XIAO Qiu-guo JIN Yi-su LIU Xiao-ping Department of Chemical Engineering Xiangtan Polytechnic Universi tyXiangtan 411201China

Ferrochrome slag is a kind of industrial waste containing Cr^(6+)and is produced in the process of silico ferrochrome *** the basis of analyzing the chemical composition and mineral composition of ferrochrome slag,this paper has put forward a technology of green portland cement clinker calcinated from ferrochrome *** the experiment,physical chemical changes of cement clinker in the burning process of ferrochrome slag were *** effects of calcinating temperature and clinker cooling rate on the solubility value of Cr^(6+)were *** results indicated that when the calcinating temperature is above 1450℃,and the cooling rate is beyond 120℃/min,Cr^(6+)in cement clinker is almost insoluble.

关键词： ferrochrome slag Cr^(6+) green cement clinker

Application of a concrete thermal pile in cooling the warming permafrost under climate change

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Advances in Climate Change Research 2024年第1期15卷 170-183页

作者： Yun-Hu SHANG fu-Jun NIU Guo-Yu LI jian-Hong FANG Ze-yong GAO State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Da Xing'anling Observation and Research Station of Frozen-Ground Engineering and Environment Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesJagdaqi 165000China Qinghai Research Institute of Transportation Xining 810008China

Permafrost degradation caused by climate warming is posing a serious threat to the stability of cast-in-place pile foundations in warm permafrost *** cold energy can be effectively utilized by two-phase closed thermosyphons(TPCTs)to cool the ***,we installed TPCTs in a cast-in-place pile foundation to create a unique structure called a thermal pile,which effectively utilizes the TPCTs to regulate ground *** we conducted a case study and numerical simulation to exhibit the cooling performance,and optimize the structure of the thermal *** purpose of this study is to promote the application of thermal piles in unstable permafrost *** on the findings,the thermal pile operated for approximately 53%of the entire year and effectively reduced the deep ground temperature at a rate of at least-0.1℃per ***,it successfully raised the permafrost table that is 0.35 m shallower than the natural ground *** characteristics prove highly beneficial in mitigating the adverse effects of permafrost degradation and enhancing infrastructure *** the length of the condenser section and the diameter of the TPCT in a suitable manner can effectively enhance the cooling capability of the thermal pile and ensure the long-term mechanical stability of the pile foundation even under climate warming.

关键词： Heat transfer Cold energy Warm permafrost Two-phase closed thermosyphons Cast-in-place pile foundation

The Essential 2-rank for Classical Groups

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2169-2186页

作者： jian Bei AN yong XU Department of Mathematics University of AucklandAucklandNew Zealand School of Mathematics and Statistics He’nan University of Science and TechnologyLuoyang 471023P.R.China

Let G be a symplectic or orthogonal group defined over a finite field with odd characteristic and let D≤G be a Sylow *** this paper,we classify the essential 2-subgroups and determine the essential 2-rank of the Frobenius category FD(G).Together with the results of An–Dietrich and Cao–An–Zeng,this completes the work of essential subgroups and essential ranks of classical groups.

关键词： Frobenius category conjugation families essential 2-rank symplectic groups orthogonal groups

Impact of initial fluctuations and nuclear deformations in isobar collisions

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Nuclear Science and Techniques 2024年第6期35卷 155-162页

作者： jian-Fei Wang Hao-Jie Xu fu-Qiang Wang Department of Modern Physics University of Science and Technology of ChinaHefei 230026China School of Science Huzhou UniversityHuzhou 313000China Strong-Coupling Physics International Research Laboratory(SPiRL) Huzhou UniversityHuzhou 313000China Department of Physics and Astronomy Purdue UniversityWest LafayetteIN 47907USA

Relativistic isobar^(96)_(44)Ru+^(96)_(44)Ru and^(96)_(40)Zr+^(96)_(40)Zrcollisions have revealed intricate differences in their nuclear size and shape,inspiring unconventional studies of nuclear structure using relativistic heavy ion *** this study,we investigate the relative differences in the mean multiplicityR_()and the secondR_(ε2)and third-order eccentricityR_(ε3)between isobar collisions using initial state Glauber *** is found that initial fluctuations and nuclear deformations have negligible effects on R_()in most central collisions,while both are important for the R_(ε2)and R_(ε3),the degree of which is sensitive to the underlying nucleonic or sub-nucleonic degree of *** features,compared to real data,may probe the particle production mechanism and the physics underlying nuclear structure.

关键词： Relativistic isobar collisions Initial fluctuations Nuclear deformation

Reliability Analysis of Reinforcement Based on GM(1,1)-Markov Semi-immersion Test

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1177-1187页

作者： fu yong QIAO Hongxia HAKUZWEYEZU Theogene School of Civil Engineering Lanzhou University of TechnologyLanzhou 730050China Gansu Advanced Civil Engineering Materials Engineering Research Center Lanzhou 730050China State Key Laboratory of Geomechanics and Geotechnical Enginering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China Civil Engineering Department University of Chinese Academy of SciencesBeijing 100049China

To investigate the corrosion degradation law and service life of reinforced concrete in various salt solution environments,reinforced concrete specimens were semi-immersed in 3%Na_(2)CO_(3)(N3-0-0),3%Na_(2)CO_(3)+3%NaCl(N3-Cl3-0)and 3%Na_(2)CO_(3)+3%NaCl+3%Na_(2)SO_(4)(N3-Cl3-S3)salt *** electrochemical workstation was used for regular non-destructive testing,and the polarization curve and related electrochemical parameters were used as the macroscopic durability evaluation indicators,while microscopic analysis of steel bar corrosion products was performed in combination with SEM and *** addition,the corrosion current density degradation model of GM(1,1)was established and compared with the modified GM(1,1)-Markov degradation *** results showed that the prediction error of the GM(1,1)-Markov model was smaller and more accurate than that of GM(1,1).The reinforced concrete specimens in the N3-0-0,N3-Cl3-0 and N3-Cl3-S3 solutions reached the failure state in 3.08,1.67,and 2.30 years,respectively,as predicted by the GM(1,1)-Markov *** to ESM and EDS microscopic analysis of reinforcement,carbonate had no significant effect on reinforcement corrosion,chloride ions played a dominant role in reinforcement corrosion,and sulfate ion improved concrete's resistance to chloride ion *** on GM(1,1)-Markov model,the failure and damage of reinforced concrete in saline soil areas can be quantitatively evaluated in the whole life cycle,which provides a theoretical basis for the early maintenance or reinforcing of reinforced concrete.

关键词： salt solution semi-immersion corrosion current density GM(1,1)-Markov

Echo State Network Based on Improved Knowledge Distillation for Edge Intelligence

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Chinese Journal of Electronics 2024年第1期33卷 101-111页

作者： jian ZHOU Yuwen jianG Lijie XU Lu ZHAO fu XIAO College of Computer Nanjing University of Posts and Telecommunications jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks

Echo state network(ESN) as a novel artificial neural network has drawn much attention from time series prediction in edge intelligence. ESN is slightly insufficient in long-term memory, thereby impacting the prediction performance. It suffers from a higher computational overhead when deploying on edge devices. We firstly introduce the knowledge distillation into the reservoir structure optimization, and then propose the echo state network based on improved knowledge distillation(ESN-IKD) for edge intelligence to improve the prediction performance and reduce the computational overhead. The model of ESN-IKD is constructed with the classic ESN as a student network, the long and short-term memory network as a teacher network, and the ESN with double loop reservoir structure as an assistant network. The student network learns the long-term memory capability of the teacher network with the help of the assistant network. The training algorithm of ESN-IKD is proposed to correct the learning direction through the assistant network and eliminate the redundant knowledge through the iterative pruning. It can solve the problems of error learning and redundant learning in the traditional knowledge distillation process. Extensive experimental simulation shows that ESN-IKD has a good time series prediction performance in both long-term and short-term memory, and achieves a lower computational overhead.

关键词： Knowledge engineering Training Performance evaluation Computational modeling Time series analysis Artificial neural networks Reservoirs

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Control of fine particulate nitrate during severe winter haze in“2+26”cities

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Journal of Environmental Sciences 2024年第2期136卷 261-269页

作者： Chuang Qin Xiao fu Tao Wang jian Gao Jiaqi Wang Institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Department of Civil and Environmental Engineering Hong Kong Polytechnic UniversityHong Kong 99907China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 10084China

The“2+26”cities,suffering the most severe winter haze pollution,have been the key region for air quality improvement in *** prominent nitrate pollution is one of the most challenging environmental issues in this region,necessitating development of an effective control ***,we use observations,and state-of-the-art model simulations with scenario analysis and process analysis to quantify the effectiveness of the future SO_(2)-NO_(X)-VOC-NH_(3) emission control on nitrate pollution mitigation in“2+26”*** on a serious winter haze episode,we find that limited NO_(X)emission reduction alone in the short-term period is a less effective choice than VOC or NH_3emission reduction alone to decrease nitrate concentrations,due to the accelerated NO_(X)-HNO_(3)conversion by atmospheric oxidants and the enhanced HNO_(3)to NO_(3)^(-)partition by ammonia,although deep NO_(X)emission reduction is essential in the long-term *** synergistic NH_(3) and VOC emission control is strongly recommended,which can counteract the adverse effects of nonlinear photochemistry and aerosol chemical feedback to decrease nitrate *** extra benefits will be reduced if the synergistic NH_(3) and VOC reduction is delayed,and thus reducing emission of multiple precursors is urgently required for the effective control of increasingly severe winter nitrate pollution in“2+26”cities.

关键词： Nitrate Winter haze pollution Emission reduction “2+26”cities

Asymmetric reversible structural switching of a diene coordination polymer promoted by UV-visible light

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Science China Chemistry 2024年第2期67卷 536-541页

作者： yong Wang Qiaoqiao Zhang yong-yong Cao Qi Liu Brendan F.Abrahams jian-Ping Lang College of Chemistry Chemical Engineering and MaterialsSoochow UniversitySuzhou215123China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China College of Biological Chemical Science and EngineeringJiaxing UniversityJiaxing314001China School of Chemistry University of MelbourneVictoria3010Australia

In natural and artificial systems,reversible reactions are commonly asymmetric with respect to the time scale and nature of the stimuli which drive the forward and backward *** applications for which switching behavior is required,it is desirable that the reversible reaction goes as close to symmetric as possible;however,such systems are ***,we report an example of ultraviolet(UV)-visible light-regulated asymmetric reversible structural switching involving a diene-based coordination polymer,CP1 and its monocyclobutane product,*** is possible to cycle at least ten times through a forward [2+2] photocycloaddition reaction and the reverse,photocleavage reaction.A single cycle can be completed within a few *** transformation is accompanied by fast and distinct fluorescence changes,arising from optimisation of the reaction *** functional theory calculations allow rationalisation of the asymmetric reversible transformation between CP1 and CP1a rather than between CP1 and its dicyclobutane product *** work provides a clear illustration of reversible structural switching which approaches symmetric behaviour with respect to reaction rate and *** insights gained from this work also assist in the design of fast,reversible switching materials.

关键词： asymmetrical reversible structural switching coordination polymer photocycloaddition UV-visible light-controlled fluorescence switching

Energy modeling and optimization of building condenser water systems with all-variable speed pumps and tower fans:A case study

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Building Simulation 2024年第7期17卷 1085-1111页

作者： yong Cao Chuang Wang Sheng Wang Xiao fu Xinguo Ming School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Air-Conditioning Equipment and System Energy Conservation Zhuhai 519070China GREE Electric Appliances Inc.of ZhuhaiZhuhai 519070China School of Environment and Energy Engineering Beijing University of Civil Engineering and ArchitectureBeijing 100044China Beijing Advanced Innovation Centerfor future Urban Design Beijing University of Civil Engineering and ArchitectureBeijing 100044China

The emergence of building condenser water systems with all-variable speed pumps and tower fans allows for increased efficiency and flexibility of chiller plants in partial load operation but also increases the control complexity of condenser water *** study aims to develop an integrated modeling technique for evaluating and optimizing the energy performance of such a condenser water *** proposed system model is based on the semi-physical semi-empirical chiller,pump,and cooling tower models,with capabilities of fully considering the hydraulic and thermal interactions in the condenser water loop,being solved analytically and much faster than iterative solvers and supporting the explicit optimization of the pump and tower fan frequency.A mathematical approach,based on the system model and constrained optimization technique,is subsequently established to evaluate the energy performance of a typical dual setpoint-based variable speed strategy and find its energy-saving potential and most efficient operation by jointly optimizing pumps and tower *** all-variable speed chiller plant from Wuhan,China,is used for a case study to validate the system model’s accuracy and explore its *** results showed that the system model can accurately simulate the condenser water system’s performance under various operating *** optimizing the frequencies of pumps and tower fans,the total system energy consumption can be reduced by 12%–13%compared to the fixed dual setpoint-based strategy with range and approach setpoints of 4℃and 2℃.In contrast,the energy-saving potential of optimizing the cooling tower sequencing is insignificant.A simple joint speed control method for optimizing the pumps and tower fans emerged,i.e.,the optimal pump and fan frequency are linearly correlated(if both are non-extremes)and depend on the chiller part load ratio only,irrespective of the ambient wet-bulb temperature and chilled water supply *** was also foun

关键词： all-variable speed chiller plant model-based optimization hydraulic and thermal coupling analytical solution dual setpoint-based variable speed control optimal joint speed control