检索结果-南通市图书馆

Prediction of solar activities:Sunspot numbers and solar magnetic synoptic maps

Science China Earth Sciences 2024年第8期67卷 2460-2477页

作者： Rui ZHUO Jiansen HE Die DUAN Rong LIN Ziqi WU limei yan Yong WEI School of Earth and Space Sciences Peking UniversityBeijing 100091China College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China Centre for Mathematical Plasma Astrophysics Department of MathematicsKU LeuvenLeuven 3001Belgium Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The evolution of solar magnetic fields is significant for understanding and predicting solar *** our knowledge of solar magnetic fields largely depends on the photospheric magnetic *** this paper,based on the spherical harmonic expansion of the photospheric magnetic field observed by Wilcox Solar Observatory,we analyze the time series of spherical harmonic coefficients and predict Sunspot Number as well as synoptic maps for Solar Cycle *** find that solar maximum years have complex short-period disturbances,and the time series of coefficient g_(7)~0 is nearly in-phase with Sunspot Number,which may be related to solar meridional *** Long Short-Term Memory networks(LSTM),our prediction suggests that the maximum of Solar Cycle 25 is likely to occur in June 2024 with an error of 8 months,the peak sunspot number may be 166.9±22.6,and the next solar minimum may occur around January *** incorporating Empirical Mode Decomposition,we enhance our forecast of synoptic maps truncated to Order 5,validating their relative *** prediction not only addresses a gap in forecasting the global distribution of the solar magnetic field but also holds potential reference value for forthcoming solar observation plans.

关键词： Solar activity prediction Solar magnetic field Spherical harmonic expansion Long-Short Term Memory(LSTM) Empirical Mode Decomposition(EMD)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Numerical manifold method for steady-state nonlinear heat conduction using Kirchhoff transformation

引用

Science China(Technological Sciences) 2024年第4期67卷 992-1006页

作者： ZHANG limei KONG Heng ZHENG Hong Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100124China Beijing Municipal Construction Co. Ltd.Beijing 100048China

The numerical manifold method(NMM)introduces the mathematical and physical cover to solve both continuum and discontinuum problems in a unified *** this study,the NMM for solving steady-state nonlinear heat conduction problems is presented,and heat conduction problems consider both convection and radiation boundary ***,the nonlinear governing equation of thermal conductivity,which is dependent on temperature,is transformed into the Laplace equation by introducing the Kirchhoff *** transformation reserves linearity of both the Dirichlet and the Neumann boundary conditions,but the Robin and radiation boundary conditions remain ***,the NMM is employed to solve the Laplace equation using a simple iteration procedure because the nonlinearity focuses on parts of the problem domain ***,the temperature field is retrieved through the inverse Kirchhoff *** examples are analyzed,demonstrating the advantages of the Kirchhoff transformation over the direct solution of nonlinear equations using the NewtonRaphson *** study provides a new method for calculating nonlinear heat conduction.

关键词： numerical manifold method nonlinear heat conduction temperature-dependent thermal conductivity Kirchhoff transformation convection and radiation boundary conditions

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Optimal Allocation of Sample Size with Uncertain Random Costs in Stratified Sampling

Optimal Allocation of Sample Size with Uncertain Random Cost...

引用

The Eleventh International Conference on Information and Management Sciences(IMS2012) in Celebrating of the 60th Birthday of Prof.Shu-Cherng Fang

作者： limei yan~1 Jianjun Liu~2 Mingfeng Zhang~1 1.Department of Mathematics Dezhou University Dezhou 253023 China 2.Department of Computer Science Dezhou University Dezhou 253023 China

＜正＞Optimal allocation problem of sample size in stratified sampling is *** randomness appears in the system,the unitary costs are described as random variables. Two optimal allocation models are proposed,one is dependentchance programming model and the other is a programming model with chance constrains.A hybrid intelligent algorithm integrated random simulation and genetic algorithm is designed to solve the proposed ***,an example about food enterprise survey is provided.

关键词： Stratified sampling Optimal allocation Dependentchance programming Hybrid intelligent algorithm Satisfactory degree of consumer

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Targeted therapeutic effects of oral magnetically driven pectin nanoparticles containing chlorogenic acid on colon cancer

引用

Particuology 2024年第1期84卷 53-59页

作者： Huatai Zhu limei Zhang Fujia Kou Jingyang Zhao Jiandu Lei Jing He Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China Institute of Biopharmaceutical and Health Engineering Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen518055China

Oral colonic nano-drug delivery system has attracted growing attention in treating colon cancer for their excellent ***,the unique and complex structure of the gastrointestinal tract is still an obstacle to the safe delivery of drugs targeting sites in colon ***,we designed magnetically driven dual-targeted oral colonic nanoparticles loaded with chlorogenic acid using pectin and oleic acid-modified iron oxide(Fe3O4@OA).Specific degradation of pectin by pectinase produced by colonic flora and magnetic fields applied to the colon confers specific targeting of nanoparticles to the *** order to overcome the challenge of preparing magnetically driven nanoparticles with small and homogeneous particle sizes by a single conventional method,we developed the combined ultrasound-emulsification *** average particle size of the prepared nanoparticles was 81.04±1.02 nm,which showed good drug release in the simulated colonic *** vitro anticancer studies,the drug-loaded nanoparticles possess an obvious toxicity and apoptosis-inducing ability against cancer ***,the hemolysis results demonstrated the safety of the nanoplatform(PET/CGA/Fe_(3)O_(4)@OA).This work holds broad prospects as a new treatment modality for colon cancer.

关键词： Pectin Chlorogenic acid Ultrasound-emulsion Magnetically driven Colon cancer Colon targeted

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Environmental benefits and farmers' adoption of winter cover crops in the North China Plain

引用

Pedosphere 2024年第1期34卷 159-169页

作者： Shufang GUO Yitao ZHANG limei ZHAI Jian LIU Hongyuan WANG Hongbin LIU State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China Key Laboratory of Nonpoint Source Pollution ControlMinistry of Agriculture and Rural AffairsInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China Institute of Agricultural Environment and Resources Yunnan Academy of Agricultural SciencesKunming 650205China Shandong Yucheng Agro-ecosystem National Observation Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China The Norwegian Institute of Bioeconomy Research(NIBIO) Akershus 1431Norway

The introduction of cover crops into monoculture systems to improve soil health has been widely adopted worldwide. However, little is known about the environmental risks and application prospects of different cover crops in spring maize(Zea mays L.) monocultures proposed in the North China Plain. A pot experiment was conducted to evaluate the effects of different winter cover crops on subsequent maize yield, soil fertility, and environmental risks of nitrogen(N) loss, and a questionnaire survey was conducted to examine factors influencing farmers' willingness to adopt cover crops in the North China Plain. Based on the same fertilization regime during the maize growing period, four winter cover crop treatments were set up, including bare fallow, hairy vetch(Vicia villosa Roth.), February orchid(Orychophragmus violaceus), and winter oilseed rape(Brassica campestris L.). The results indicated that winter cover crops significantly increased subsequent maize yield and soil organic carbon, total N, and microbial biomass carbon and N compared with the bare fallow *** incorporation of cover crops led to a negligible increase in nitrous oxide(N_(2)O) emissions and had a very limited effect on ammonia(NH_(3)) *** incorporation of February orchid and winter oilseed rape decreased nitrate leaching compared with the hairy vetch treatment in the maize growing *** N losses via N_(2)O and NH_(3) emissions and N leaching accounted for 71%–84% of the N surplus. However, yield increase and environmental benefits were not the main positive factors for farmers to accept cover crops. Financial incentive was rated by 83.9% of farmers as an “extremely important” factor, followed by other costs, when considering winter cover cropping. These results indicate that the environmental benefits depend on the type of cover crop. Maintaining high levels of soil fertility and maize yield, providing sufficient subsidies, and encouraging large-area cultivation of cover crops

关键词： cover crop N leaching NH_(3)emission N_(2)O emission spring maize willingness to accept

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Process design and intensification of multicomponent azeotropes special distillation separation via molecular simulation and system optimization

引用

Chinese Journal of Chemical Engineering 2024年第7期71卷 24-44页

作者： Chunliang Liu Jianhui Zhong Ranran Wei Jiuxu Ruan Kaicong Wang Zhaoyou Zhu Yinglong Wang limei Zhong College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China

This work provides an overview of distillation processes,including process design for different distillation processes,selection of entrainers for special distillation processes,system integration and intensification of distillation processes,optimization of process parameters for distillation processes and recent research progress in dynamic control ***,the feasibility of using thermodynamic topological theories such as residual curve,phase equilibrium line and distillation boundary line to analyze different separation regions is discussed,and the rationality of distillation process design is discussed by using its ***,the application of molecular simulation methods such as molecular dynamics simulation and quantum chemical calculation in the screening of entrainer is discussed for the extractive distillation *** thermal coupling mechanism of different distillation processes is used to explore the process of different process ***,a mixed integer nonlinear optimization strategy for the distillation process based on different algorithms is ***,the improvement of dynamic control strategies for different distillation processes in recent years is *** work focuses on the application of process intensification and system optimization in the design of distillation process,and analyzes the challenges,prospects,and development trends of distillation technology in the separation of multicomponent azeotropes.

关键词： Azeotrope separation Process design Optimization algorithm Process integration Dynamic control Entrainer selection

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Tuning the cross-linked structure of basic poly(ionic liquid)to develop an efficient catalyst for the conversion of vinyl carbonate to dimethyl carbonate

引用

Chinese Journal of Chemical Engineering 2024年第8期72卷 106-116页

作者： Zhaoyang Qi Shiquan Zhong Huiyun Su Changshen Ye limei Ren Ting Qiu Jie Chen College of Chemical Engineering Fuzhou UniversityFuzhou 350108China Department of Chemical Engineering Shijiazhuang UniversityShijiazhuang 050035China Qingyuan Innovation Laboratory Quanzhou 362801China Fuzhou University International Joint Laboratory of Thermochemical Conversion of Biomass Fuzhou UniversityFuzhou 350108China

Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other *** current primary industrial process employs a conventional sodium methoxide basic catalyst to produce DMC through the transesterification reaction between vinyl carbonate and ***,the utilization of this catalyst presents several challenges during the process,including equipment corrosion,the generation of solid waste,susceptibility to deactivation,and complexities in separation and *** address these limitations,a series of alkaline poly(ionic liquid)s,i.e.[DVBPIL][PHO],[DVCPIL][PHO],and[TBVPIL][PHO],with different crosslinking degrees and structures,were synthesized through the construction of cross-linked polymeric monomers and *** poly(ionic liquid)s exhibit cross-linked structures and controllable cationic and anionic *** was conducted to investigate the effect of the cross-linking degree and structure on the catalytic performance of transesterification in synthesizing *** was discovered that the appropriate cross-linking degree and structure of the[DVCPIL][PHO]catalyst resulted in a DMC yield of up to 80.6%.Furthermore,this catalyst material exhibited good stability,maintaining its catalytic activity after repeated use five times without significant *** results of this study demonstrate the potential for using alkaline poly(ionic liquid)s as a highly efficient and sustainable alternative to traditional catalysts for the transesterification synthesis of DMC.

关键词： Poly(ionic liquid) Cross-linking degree Dimethyl carbonate production Transesterification reaction Mechanism

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhanced Cooling Efficiency of Urban Trees on Hotter Summer Days in 70 Cities of China

引用

Advances in Atmospheric Sciences 2024年第11期41卷 2259-2275页

作者： limei yanG Jun GE Yipeng CAO Yu LIU Xing LUO Shiyao WANG Weidong GUO School of Atmospheric Sciences Nanjing UniversityNanjing 210023China Joint International Research Laboratory of Atmospheric and Earth System Sciences Nanjing UniversityNanjing 210023China Frontiers Science Center for Critical Earth Material Cycling Nanjing UniversityNanjing 210023China

Increasing the urban tree cover percentage(TCP) is widely recognized as an efficient way to mitigate the urban heat island effect. The cooling efficiency of urban trees can be either enhanced or attenuated on hotter days, depending on the physiological response of urban trees to rising ambient temperature. However, the response of urban trees' cooling efficiency to rising urban temperature remains poorly quantified for China's cities. In this study, we quantify the response of urban trees' cooling efficiency to rising urban temperature at noontime [~1330 LT(local time), LT=UTC+8] in 17summers(June, July, and August) from 2003–19 in 70 economically developed cities of China based on satellite observations. The results show that urban trees have stronger cooling efficiency with increasing temperature, suggesting additional cooling benefits provided by urban trees on hotter days. The enhanced cooling efficiency values of urban trees range from 0.002 to 0.055℃ %-1 per 1℃ increase in temperature across the selected cities, with larger values for the lowTCP-level cities. The response is also regulated by background temperature and precipitation, as the additional cooling benefit tends to be larger in warmer and wetter cities at the same TCP level. The positive response of urban trees' cooling efficiency to rising urban temperature is explained mainly by the stronger evapotranspiration of urban trees on hotter *** results have important implications for alleviating urban heat risk by utilizing urban trees, particularly considering that extreme hot days are becoming more frequent in cities under global warming.

关键词： urban trees cooling efficiency China's cities evapotranspiration summer hot days

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Environmental,economic and exergy analysis of separation of ternary azeotrope by variable pressure extractive distillation based on multi-objective optimization

引用

Chinese Journal of Chemical Engineering 2024年第1期65卷 145-157页

作者： Peizhe Cui Jiafu Xing Chen Li Mengjin Zhou Jifu Zhang Yasen Dai limei Zhong Yinglong Wang College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China

In this work,the ternary azeotrope of tert-butyl alcohol/ethyl acetate/water is separated by extractive distillation(ED)to recover the available constituents and protect the *** on the conductor like shielding model and relative volatility method,ethylene glycol was selected as the extractant in the separation *** addition,in view of the characteristic that the relative volatility between components changes with pressure,the multi-objective optimization method based on nondominated sorting genetic algorithm II optimizes the pressure and the amount of solvent cooperatively to avoid falling into the optimal local *** on the optimal process parameters,the proposed heat-integrated process can reduce the gas emissions by 29.30%.The heat-integrated ED,further coupled with the pervaporation process,can reduce gas emission by 42.36%and has the highest exergy efficiency of 47.56%.In addition,based on the heat-integrated process,the proposed two heat pump assisted heat-integrated ED processes show good economic and environmental *** double heat pump assisted heat-integrated ED can reduce the total annual cost by 28.78%and the gas emissions by 55.83%compared with the basis process,which has a good application *** work provides a feasible approach for the separation of ternary azeotropes.

关键词： Extractive distillation Optimization Mixtures Separation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

One-pot Synthesis of MoO_(3)/PI Composite with Enhanced Photocatalytic Performance for Oxidative Coupling of Amines to Imines

引用

China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 57-71页

作者： Zhao Wenjie Du Chengxin Song Yu Zhou Yafen Wang Qing Zhou limei Xu Bin Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province College of Chemistry and Chemical EngineeringChina West Normal UniversityNanchongChina Key Laboratory of Green Chemistry of Sichuan Institutes of Higher Education Sichuan University of Science&EngineeringZigongChina

Organic-inorganic MoO_(3)/PI(MoPI)composites were prepared using a simple one-pot thermal copolymerization *** resulting composites exhibited enhanced photocatalytic activity for the selective oxidation of benzylamine to N-benzylidene benzylamine(N-BDBA)in ambient air under simulated solar light irradiation compared to pristine MoO_(3) or polyimide(PI).In particular,the MoPI composite with a 0.3:1 molar ratio of Mo to melamine,referred to as MoPI-0.3,demonstrated the best performance in the photo-oxidation of benzylamine,achieving a benzylamine conversion of 95%with a N-BDBA selectivity exceeding 99%after 3 h *** enhanced photocatalytic activity of the MoPI-0.3 catalyst was attributed to the formation of a direct Z-scheme heterojunction between MoO_(3) and PI,facilitating more efficient separation of the photoinduced electrons and ***,the MoPI-0.3 composite maintained considerably high activity over four consecutive cycles,highlighting its good stability and ***,the MoPI-0.3 composite could photo-oxidize benzylamine derivatives and heterocyclic amines to their corresponding imines,demonstrating the universal applicability of this composite catalyst.

关键词： MoO3/PI composite photocatalysis amine oxidation imine

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：