检索结果-南通市图书馆

Exact Eigenstates for a Class of Models Describing Multiphoton Processes in the Presence of Six Bosonic Modes

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2004年第6期21卷 983-986页

作者： ZHANZhi-Ming LIWei-bin LIJia-Hua YANGWen-xing CHENAi-xi StateKeyLaboratoryofLaserTechnology HuazhongUniversityofScienceandTechnologyWuhan430074 DepartmentofPhysics HuazhongUniversityofScienceandTechnologyWuhan430074 CentreforColdAtomPhysics ChineseAcademyofSciencesWuhan430071

We present an efficient approach to study the spectra and eigenstates for the model describing six multiphoton processes in the presence of bosonic modes without using the assumption of the Bethe ansatz. The exact analytical results of all the eigenstates and eigenvalues are in terms of a parameter λ for a class of models describing the six-mode multiphoton processes. The parameter is determined by the roots of a polynomial and is solvable analytically or numerically.

关键词： Multiphoton processes

关于大陆“社会网络”研究的iView分析及知识视图

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

系统工程理论与实践 2013年第7期33卷 1661-1671页

作者：罗斌唐锡晋中联重科股份有限公司长沙410013 中国科学院数学与系统科学研究院北京100190

相对于期刊文章需经历较长的评审过程,学术会议报告和论文能反映领域研究的最新成果,考察某领域的旗舰会议并对其跟踪有助于较快地把握研究脉络.简要介绍iView分析这一定性综合集成技术基本原理后,将iView分析技术应用于中国社会网研究... 详细信息

相对于期刊文章需经历较长的评审过程,学术会议报告和论文能反映领域研究的最新成果,考察某领域的旗舰会议并对其跟踪有助于较快地把握研究脉络.简要介绍iView分析这一定性综合集成技术基本原理后,将iView分析技术应用于中国社会网研究学会的年会"社会网与关系管理研讨会"这一社会网领域在中国的代表性会议,探测当前研究概况、主要议题、主要研究人员等,进而考察系列研讨会所反映的该领域研究的地域特性、学科特性、时代特性及研究趋势.如此展示支持快速准确勾画研究主题的知识视图的定性研究中智能信息技术的应用.

关键词： iView分析 iView网络社会网关系管理知识视图

Sea-water-level prediction via combined wavelet decomposition,neuro-fuzzy and neural networks using SLA and wind information

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2020年第5期39卷 157-167页

作者： Bao Wang bin Wang Wenzhou Wu Changbai xi Jiechen Wang School of Geography and Ocean Science Nanjing UniversityNanjing 210023China National Marine Environmental Forecasting Center Beijing 100081China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Nanjing UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing UniversityNanjing 210023China

Sea-water-level(SWL)prediction significantly impacts human lives and maritime activities in coastal regions,particularly at offshore locations with shallow water ***-term SWL forecasts,which are conventionally obtained via harmonic analysis,become ineffective when nonperiodic meteorological events *** intelligence combined with other data-processing methods can effectively forecast highly nonlinear and nonstationary inflow patterns by recognizing historical relationships between input and *** techniques are considerably useful in time-series data *** paper reports the development of a hybrid model to realize accurate multihour SWL forecasting by combining an adaptive neuro-fuzzy inference system(ANFIS)with wavelet decomposition while using sea-level anomaly(SLA)and wind-shear-velocity components as *** wavelet-ANFIS(WANFIS)models have been tested using different inputs to assess their applicability as alternatives to the artificial neural network(ANN),wavelet ANN(WANN),and ANFIS *** error definitions have been used to evaluate results,which indicate that integrated wavelet-decomposition and ANFIS models improve the accuracy of SWL prediction and that the inputs of SLA and wind-shear velocity exhibit superior prediction capability compared to conventional SWL-only models.

关键词： sea-water level prediction ANFIS wavelet decomposition wind

Synergistic responses of NHX, AKT1, and SOS1 in the control of Na^+ homeostasis in sweet sorghum mutants induced by ^(12)C^(6+)-ion irradiation

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2018年第1期29卷 32-38页

作者： Wen-Ting Gu Li-bin Zhou Rui-Yuan Liu Wen-Jie jin Ying Qu xi-Cun Dong Wen-Jian Li Institute of Modern Physics Chinese Academy of Sciences

Sweet sorghum mutants induced by^(12)C(6+)-ion irradiation were planted under different soil salinity conditions to investigate the mechanisms maintaining the transport and spatial distribution of Na^+. The functions of the synergistic responses of NHX, AKT1, and SOS1 related to Na^+ accumulation were investigated in control(KFJT-CK) sorghum and KF1210-3 and KF1210-4 mutants. The results indicated that the NHX, AKT1, and SOS1 proteins in sweet sorghum are mainly involved in the transport, exclusion, and spatial distribution of Na^+,respectively. In addition to physiological parameters, we also measured the expression levels of NHX, AKT1, and SOS1 genes. The experimental results indicated that 150 m M Na Cl induced marked increases in the transcripts of NHX and SOS1 after 8 and 12 h in the KF1210-3,KF1210-4, and KFJT-CK cultivars. In contrast, however, a decrease in AKT1 was observed. On the basis of our results, we propose a model in which cooperation amongNHX, AKT1, and SOS1 facilitates Na^+ homeostasis in sweet sorghum in response to an increase in salt concentration. Accordingly, study of the regulatory mechanisms in sweet sorghum generated by carbon ion irradiation is essential for the selection of salt-tolerant cultivars.

关键词： 12C6+-ion irradiation Sweet sorghum Salt stress NHX AKT1 SOS1

Predication of Selective Ring-opening Hydrogenolysis for Furfuryl Alcohol to Produce Pentanediol over Dual-atom Catalysts

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2024年第1期40卷 55-63页

作者： WANG Tingting WANG Jia xi Yongjie HU bin LI Fuwei State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Selective activation of C-O bond is of fundamental importance in the precise conversion of oxygenates into value-added compounds in an atom-economic and sustainable manner, and meanwhile, the structurally well-defined dual-atoms catalysts (DACs) have been scarcely investigated in this field. In this study, a series of transition metal DACs anchored on nitrogen-doped graphene (TM2/NC, TM=Pt, Ir, Rh, Pd, Ru, Co, Ni and Cu) was constructed to make a comprehensive investigation of their selectivity in the hydrogenative transformation of furfuryl alcohol (FAL), an important biomass platform molecule, to 1,2-pentanediol (1,2-PeD) via selective cleavage of furanic C5-O bond, by density functional theory (DFT) calculations and microkinetic modeling. We found that Ir2/NC demonstrated a high selectivity for the cleavage of furanic C5-O bond to produce 1,2-PeD, while the production of THFAL or 1,5-pentanediol (1,5-PeD) on other TM2/NC catalysts are more favorable. Furthermore, we found that the selective C-O bond cleavage of FAL furan ring is affected by the orbital overlap between the d-orbitals of the anchored metal atoms and the p-orbitals of the adsorbed C atom in FAL, suggesting that the selectivity of the C-O bond cleavage is inextricably related with the electronic property of the anchored metals.

关键词： Furfuryl alcohol Hydrogenation Dual-atom catalyst Density functional theory(DFT)calculation

Metadynamic recrystallization behaviors of SA508Gr.4N reactor pressure vessel steel during hot compressive deformation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2021年第1期28卷 46-57页

作者： Shi-bin Qiao Zheng-dong Liu xi-kou He Chang-sheng xie Institute for Special Steels Central Iron and Steel Research InstituteBeijing 100081China Collaborative Innovation Centre of Steel Technology University of Science and Technology BeijingBeijing 100083China

The metadynamic recrystallization(MDRX)model is established,and the coefficients determined by multiple linear regression analysis are used to describe the microstructure evolution of SA508Gr.4N *** effects of compression temperature of 950–1150℃,strain rate of 0.001–0.1 s^(-1),pre-strain of 0.3–0.6,initial austenite grain size(IAGS)of 136–552 lm,and interval time of 1–300 s on the MDRX kinetics and microstructure evolution were analyzed,using twopass compression test method on Gleeble thermo-mechanical *** results show that MDRX kinetics and austenite grain size are strongly dependent on compression temperature and strain rate,MDRX volume fraction increases with increasing compression temperature and strain rate,and the grain size decreases with increasing strain rate and decreasing compression temperature,while less affected by the pre-strain and ***,the values predicted using MDRX model and the ones calculated from experiment are compared,and the results show that the proposed model can give a reasonable estimate of MDRX behavior for SA508Gr.4N steel.

关键词： SA508Gr.4N steel Metadynamic recrystallization Kinetic model Grain size model

Transition Metal Boride-Based Materials for Electrocatalytic Water Splitting

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2022年第9期41卷 8-44页

作者： Feng-Ge Wang xin Liu Qian-xi Lv bin Liu Yong-Ming Chai bin Dong State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China

Electrocatalytic water splitting to produce hydrogen is an eco-friendly way to achieve sustainable utilization of renewable *** industrial application of water electrolysis, which is severely limited by slow kinetic reactions on electrode surfaces, requires the development of highly reactive, low-cost and stable electrocatalytic materials. Transition metal borides/borates have recently emerged as promising electrocatalytic materials for catalyzing hydrogen/oxygen evolution reactions(HER/OER) in inexpensive electrolyzers. However, so far, there has been little comprehensive summary of transition metal borides/borates. Here, this review provides the latest research progress on transition metal borides/borates for electrocatalytic water splitting. The structural characteristics of transition metal borides/borates and their synthesis methods in recent years are discussed. Then, the theoretical and experimental progress of transition metal borides including single-metal borides, multi-metal borides, borate derived and other nanocomposites containing boron(boron-doped nanocomposites/substrate with boron) in electrocatalytic reaction and the role of boron in regulating electrocatalytic performance are further emphasized. Finally, the potential challenges and future prospects of transition metal borides/borates in electrocatalysis are presented.

关键词： transition metal borides/borates electrocatalysts hydrogen evolution reaction(HER) oxygen evolution reaction(OER) overall water splitting

What and where: A context-based recommendation system for object insertion

在线全文

学校读者我要写书评

暂无评论

Computational Visual Media 2020年第1期6卷 79-93页

作者： Song-Hai Zhang Zheng-Ping Zhou bin Liu xi Dong Peter Hall Tsinghua University Beijing 100084China Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084China Department of Computer Science Media Technology Research Center University of BathBath BA27AYUK

We propose a novel problem revolving around two tasks:(i)given a scene,recommend objects to insert,and(ii)given an object category,retrieve suitable background scenes.A bounding box for the inserted object is predicted in both tasks,which helps downstream applications such as semiautomated advertising and video *** major challenge lies in the fact that the target object is neither present nor localized in the input,and furthermore,available datasets only provide scenes with existing *** tackle this problem,we build an unsupervised algorithm based on object-level contexts,which explicitly models the joint probability distribution of object categories and bounding boxes using a Gaussian mixture *** on our own annotated test set demonstrate that our system outperforms existing baselines on all sub-tasks,and does so using a unified *** extensions and applications are suggested.

关键词： object recommendation bounding box prediction image composition object-level context

A comprehensive comparison of different regression techniques and nature-inspired optimization algorithms to predict carbonation depth of recycled aggregate concrete

在线全文

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第1期18卷 30-50页

作者： bin xi Ning ZHANG Enming LI Jiabin LI Jian ZHOU Pablo SEGARRA Department of Civil and Environmental Engineering Politecnico Di MilanoMilano 20133Italy Leibniz Institute of Ecological Urban and Regional Development(IOER) Dresden 01217Germany Universidad Politécnica de Madrid-ETSI Minas y Energía Madrid 28003Spain Department of Civil Engineering KU Leuven CampusBrugge 8200Belgium School of Resources and Safety Engineering Central South UniversityChangsha 410083China

The utilization of recycled aggregates(RA)for concrete production has the potential to offer substantial environmental and economic ***,RA concrete is plagued with considerable durability concerns,particularly *** advance the application of RA concrete,the establishment of a reliable model for predicting the carbonation is *** the one hand,concrete carbonation is a long and slow process and thus consumes a lot of time and energy to *** the other hand,carbonation is influenced by many factors and is hard to *** this,this paper proposes the use of machine learning techniques to establish accurate prediction models for the carbonation depth(CD)of RA *** types of regression techniques and meta-heuristic algorithms were employed to provide more alternative predictive *** was found that the best prediction performance was obtained from extreme gradient boosting-multi-universe optimizer(XGB-MVO)with R^(2) value of 0.9949 and 0.9398 for training and testing sets,***-MVO was used for evaluating physical laws of carbonation and it was found that the developed XGB-MVO model could provide reasonable predictions when new data were *** also showed better generalization capabilities when compared with different models in the ***,this paper emphasizes the need for sustainable solutions in the construction industry to reduce its environmental impact and contribute to sustainable and low-carbon economies.

关键词： recycled aggregate concrete carbonation depth nature-inspired optimization algorithms extreme gradient boosting technique parametric analysis