检索结果-南通市图书馆

Oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions via Prufer transformation

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 191-200页

作者： LI zhi-yu LI Kun CAI jin-ming QIN Jian-fang ZHENG Zhao-wen School of Mathematical Sciences Qufu Normal UniversityQufu 273165China College of Mathematics and Systems Science Guangdong Polytechnic Normal UniversityGuangzhou 510665China

A class of Sturm-Liouville problems with discontinuity is studied in this *** oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are *** main method used in this paper is based on Prufer transformation,which is different from the classical ***,we give two examples to verify our main results.

关键词： Sturm-Liouville problem interface condition oscillatory solution

Graphdiyne(C_(n)H_(2n-2))as an"electron transfer bridge"boosting photocatalytic hydrogen evolution over Zn_(0.5)Co_(0.5)S/MoS_(2)S-scheme heterojunction

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第5期43卷 1999-2014页

作者： Mei Li jing-zhi Wang zhi-Liang jin School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan 750021China School of Chemistry and Chemical Engineering Ningxia Key Laboratory of Solar Chemical Conversion TechnologyKey Laboratory for Chemical Engineering and TechnologyState Ethnic Affairs CommissionNorth Minzu UniversityYinchuan 750021China

In the process of photocatalytic water cracking,the migration rate and utilization rate of photogenerated charges determine the hydrogen evolution performance of the *** this paper,a carbon isotope superconducting material graphdiyne(GDY)is prepared by mechanical ball milling and introduced into the S-scheme heterojunction Zn_(0.5)Co_(0.5)S/MoS_(2)inorganic *** terms of hydrogen evolution kinetics,GDY acts as an electron bridge,not only accelerating the migration of photogenerated carriers but also improving the utilization of photogenerated ***,the large twodimensional layer provides more loading and anchoring points for Zn_(0.5)Co_(0.5)S/MoS_(2),which increases the number of active *** ternary composite catalyst 20%GDY/Zn_(0.5)Co_(0.5)S/MoS_(2)(20-GCSM)generates 69.94μmol of hydrogen(5 h)in triethanolamine *** is 2.97 and1.80 times higher than Zn_(0.5)Co_(0.5)S and Zn_(0.5)Co_(0.5)S/MoS_(2),*** the cyclic experiment,it still has stable hydrogen evolution performance after standing for24 h(under dark conditions).In addition,the potential mechanism of photocatalytic hydrogen evolution is demonstrated through in-situ X-ray photoelectron *** work provides a reference for further research in the field of introducing carbon materials into photocatalytic systems and improving the utilization of photogenerated charges.

关键词： Graphdiyne S-scheme heterojunction Electron transfer bridge Hydrogen production

Monolayer graphene/GaN heterostructure photodetector with UV‑IR dual‑wavelength photoresponses

在线全文

学校读者我要写书评

暂无评论

Frontiers of Optoelectronics 2024年第2期17卷 61-68页

作者： Junjun Xue Jiaming Tong Zhujun Gao Zhouyu Chen Haoyu fang Saisai Wang Ting zhi jin Wang College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China Portland Institute Nanjing University of Posts and TelecommunicationsNanjing 210023China

An ultraviolet-infrared(UV-IR)dual-wavelength photodetector(PD)based on a monolayer(ML)graphene/GaN heterostructure has been successfully fabricated in this *** ML graphene was synthesized by chemical vapor deposition(CVD)and subsequently transferred onto GaN substrate using polymethylmethacrylate(PMMA).The morphological and optical properties of the as-prepared graphene and GaN were *** fabricated PD based on the graphene/GaN heterostructure exhibited excellent rectify behavior by measuring the current–voltage(I–V)characteristics under dark conditions,and the spectral response demonstrated that the device revealed an UV-IR dual-wavelength *** addition,the energy band structure and absorption properties of the ML graphene/GaN heterostructure were theoretically investigated based on density functional theory(DFT)to explore the underlying physical mechanism of the two-dimensional(2D)/three-dimensional(3D)hybrid heterostructure PD *** work paves the way for the development of innovative GaNbased dual-wavelength optoelectronic devices,offering a potential strategy for future applications in the field of advanced photodetection technology.

关键词： Wide bandgap semiconductors Graphene Dual-wavelength Photodetector

Superior compound coatings prepared by low-temperature vanadium-nitrocarburizing duplex treatment

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第4期43卷 1828-1835页

作者： Gen jin fang-fang Xu Xun-Xun Hu Yue Xu School of Chemistry Beihang UniversityBeijing100191China Guobiao(Beijing)Testing and Certification Co. LtdBeijing100088China School of Materials Science and Engineering Beihang UniversityBeijing100191China

Superior compound coatings were prepared on CK45 steel surface by vanadium-nitrocarburizing duplex treatment in low-temperature salt *** this study,the microhardness,the phase constitution and the compositional distribution in the coatings prepared under different conditions were systematically *** results indicated that the reactions among activated vanadium,carbon and nitrogen atoms occurred on the steel surface,leading to the formation of compound coatings composed of outermost and compound *** mechanism for the formation of compound layer as well as the growth kinetics of the layer was also *** the duplex treatment,the wear and corrosion resistances of steel surface were significantly *** was found that the growth kinetics of compound layer obeyed the parabolic law,with the activation energy of 122.82 kJ·moL^(-1).

关键词： Vanadium-nitrocarburizing duplex treatment Compound coatings Microstructure Formation mechanism Growth kinetics

Adaptive Algorithms on Maximizing Monotone Nonsubmodular Functions

在线全文

学校读者我要写书评

暂无评论

Journal of the Operations Research Society of China 2024年第2期12卷 428-445页

作者： Bin Liu Hui Su Shu-fang Gong Qi-zhi fang School of Mathematical Sciences Ocean Universityof ChinaQingdao266100ShandongChina

Submodular optimization is widely used in large *** order to speed up the problems solving,it is essential to design low-adaptive algorithms to achieve acceleration in *** general,the function values are given by a value oracle,but in practice,the oracle queries may consume a lot of ***,how to strike a balance between optimizing them is *** this paper,we focus on maximizing a normalized and strictly monotone set function with the diminishing-return ratio under a cardinality constraint,and propose two algorithms to deal with *** apply the adaptive sequencing technique to devise the first algorithm,whose approximation ratio is arbitrarily close to 1-e^(-γ)in O(logn·log(log k/γ)) adaptive rounds,and requires O(logn^(2)·log(log k/γ)) *** by adding preprocessing and parameter estimation steps to the first algorithm,we get the second *** second algorithm trades a small sacrifice in adaptive complexity for a significant improvement in query *** the same approximation and adaptive complexity,the query complexity is improved *** the best of our knowledge,this is the first paper of designing adaptive algorithms for maximizing a monotone function using the diminishing-return ratio.

关键词： Approximation algorithm Adaptivity Nonsubmodular maximization Cardinality constraint

Flocking of a Cucker–Smale Type Model with Compactly Supported Interaction Functions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第9期40卷 2285-2296页

作者： Chun Yin jin Shuang zhi LI College of Science China Agricultural UniversityBeijing 100083P.R.China

How to analyze flocking behaviors of a multi-agent system with local interaction functions is a challenging problem in *** and Tadmor in 2011 also stressed the significance to assume that the interaction function is rapidly decaying or cut-off at a finite distance(*** and Tadmor in ***.2011).In this paper,we study the flocking behavior of a Cucker–Smale type model with compactly supported interaction *** properties of a connected stochastic matrix,together with an elaborate analysis on perturbations of a linearized system,we obtain a sufficient condition imposed only on model parameters and initial data to guarantee ***,it is shown that the system achieves flocking at an exponential rate.

关键词： Cucker-Smale model local interaction flocking stochastic matrix neighbor graph

Kinetic model of vibration screening for granular materials based on biological neural network

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第5期88卷 98-106页

作者： Zhan Zhao Yan Zhang fang Qin Mingzhi jin School of Agricultural Engineering Jiangsu UniversityZhenjiang212013China Shandong Academy of Agricultural Machinery Sciences Ji'nan250100China

The kinetic model is the theoretical basis for optimizing the structure and operation performance of vibration screening *** this paper,a biological neurodynamic equation and neural connections were established according to the motion and interaction properties of the material under vibration *** material feeding to the screen and the material passing through apertures were considered as excitatory and inhibitory inputs,respectively,and the generated stable neural activity landscape was used to describe the material distribution on the 2D screen *** dynamic process of material vibration screening was simulated using discrete element method(DEM).By comparing the similarity between the material distribution established using biological neural network(BNN)and that obtained using DEM simulation,the optimum coefficients of BNN model under a certain screening parameter were determined,that is,one relationship between the BNN model coefficients and the screening operation parameters was *** screening parameters were randomly selected,and the corresponding relationships were established as a ***,with straw/grain ratio,aperture diameter,inclination angle,vibration strength in normal and tangential directions as inputs,five independent adaptive neuro-fuzzy inference systems(ANFIS)were established to predict the optimum BNN model coefficients,*** training results indicated that ANFIS models had good stability and *** flexibility and adaptability of the proposed BNN method was demonstrated by modeling material distribution under complex feeding conditions such as multiple regions and non-uniform rate.

关键词： Kinetic model Material distribution Vibration screening Biological neural network DEM simulation Adaptive neuro-fuzzy inference systems

Successful management of severe hypoglycemia induced by total parenteral nutrition in patients with hepatocellular injury: Three cases reports

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2024年第1期12卷 157-162页

作者： Ling-zhi fang Hui-Xin jin Na Zhao Yu-Pei Wu Ying-Qin Shi Department of Pharmacy Hebei Key Laboratory of Clinical PharmacyHebei General HospitalShijiazhuang 050051Hebei ProvinceChina

BACKGROUND Glucose imbalance is common in total parenteral nutrition(TPN).Hypoglycemia seems to be less frequent than hyperglycemia,but it influences the clinical outcome to a greater ***,it should be effectively prevented and ***,there is no relevant report on how to treat hypoglycemia caused by TPN in patients with liver cell *** SUMMARY We present three patients with liver cell injury who developed severe hypo-glycemia during or after TPN *** causes of severe hypoglycemia and glucose-raising strategies were *** to the physiological charac-teristics of the hepatocellular injury,the ratio of nutrition components prescribed in TPN was appropriately adjusted for the three *** simultaneously reduced the dose of insulin and fat emulsion,and increased the dose of glucose in *** blood glucose level was restored to normal range and clinical symptoms were *** When hypoglycemia occurs during or after TPN in patients with hepatocellular injury,physicians need to simultaneously reduce insulin and fat emulsion,and increase glucose,and correct severe hypoglycemia in time to reduce its adverse consequences.

关键词： Total parenteral nutrition Hepatocellular injury Severe hypoglycemia Treatment Causes Case report

Combustion mechanism of benzene in iron ore sintering process:experimental and simulation

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 2024年第1期31卷 195-203页

作者： zhi-gang Que jin-ming Shi Xian-bin Ai Institute of Energy Research Jiangxi Academy of ScienceNanchang330096JiangxiChina Jiangxi Carbon Neutralization Research Center Nanchang330096JiangxiChina

Benzene is a typical component of volatile organic compounds(VOCs)in the iron ore sintering flue *** combustion behavior of benzene directly affects the emission of VOCs in iron ore sintering *** effects of temperature,benzene,and oxygen concentrations on the conversion ratio of benzene were investigated by experiments and numerical *** experiments were carried out in a tube reactor at temperatures of 773-1098 K,benzene concentrations of 0.01-0.03 vol.%,and oxygen concentrations of 10-21 vol.%.The numerical simulation was performed with the plug flow model in the CHEMKIN program based on a kinetic model that consists of 132 chemical species and 772 elementary step-like *** experimental results reveal that increasing the temperature and benzene concentration could signifi-cantly promote benzene *** is attributed to the increase in the reaction rates of all steps in the pathway for forming CO_(2)and H_(2)*** addition,due to the large equivalent ratio of oxygen to benzene,the conversion ratio of benzene remained constant at different oxygen *** simulation results were in good agreement with the experimental results and indicated that six elementary reactions dominated the formations of CO_(2)and H_(2)*** oxidations of C_(6)H_(5)O,CO,and C_(5)H_(4)O intermediates to CO_(2)were the limiting steps in the reaction pathways.

关键词： Benzene Volatile organic compound Iron ore sinter Combustion Simulation Temperature Oxygen