检索结果-南通市图书馆

Effect of wall temperature modulation on the heat transfer characteristics of droplet-train flow inside a rectangular microchannel

引用

Chinese Journal of Chemical Engineering 2020年第3期28卷 685-697页

作者： vivekanand S.v.B.,Raju v.R.K. Department of Mechanical Engineering National Institute of TechnologyWarangalTelangana 506004India

The numerical studies of water–oil two-phase slug flow inside a two-dimensional vertical microchannel subjected to modulated wall temperature boundary conditions have been discussed in the present *** researchers have contributed their efforts in exploring the characteristics of Taylor flows inside microchannel under constant wall heat flux or isothermal wall ***,there is no study available in the literature which discusses the impact of modulated thermal wall boundary conditions on the heat transfer behavior of slug flows inside ***,to bridge this gap,an effort has been made to understand the heat transfer characteristics of the flow under sinusoidal wall temperature ***,a single phase flow and heat transfer study was performed in microchannels,and the results of the fully developed velocity profile and heat transfer rate were validated with benchmark analytical *** an optimal selection of the combination of sinusoidal thermal wall boundary conditions has been made for the two-phase slug flow ***,the effects of amplitude(0 bεb 0.03)and frequency(0 bωb 750πrad·s-1)of the sinusoidal wall temperature profile on the heat transfer have been studied using the optimal combination of the wall boundary *** results of the numerical study using modulated temperature conditions on channel walls showed a significant improvement in the heat transfer over liquid-only flow by approximately 50%as well as over two-phase flow without wall temperature *** non-dimensional temperature contours obtained for different cases of temperature modulation clearly explain the root cause of such improvement in the heat ***,the results based on the hydrodynamics of the flow have also been reported in terms of variation of droplet shapes and film *** influence of Capillary number on the film thickness as well as heat transfer rates has also been *** addition,the measured fil

关键词： Heat transfer Microchannel Modulation Surface tension Taylor flow

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

Bedrock outcropping in the accumulation zone of the largest glacier in Mexico(Glaciar Norte of Citlaltépetl),as evidence of a possible accelerated extinction

引用

Journal of Mountain Science 2023年第2期20卷 338-354页

作者： SOTO víctor Colegio de Geografía Facultad de EconomíaUniversidad VeracruzanaAv.Xalapa s/nObrero Campesina91020XalapaVer.México

The highest volcano in Mexico,at the same time the third largest mountain in North America(Citlaltépetl,5610 m a.s.l.),is home to the largest glacier in the *** of the extinction of the Popocatépetl glacier(5500 m a.s.l.)caused by eruptive activity,and the almost disappearance of the Iztaccíhuatl glaciers(5220 m a.s.l.)due to the lower elevation of the mountain,the Glaciar Norte of Citlatépetl has been the only glacier that has shown a certain degree of stability as a response to the altitude in which it is ***,as occurs in almost all glaciers on the planet,the retreat of its glacier terminus has been ***,during the last years the thickness of its upper part began to decrease rapidly until its bedrock was exposed for the first time in *** to its ecosystem importance and because it is the main glacier in Mexico,as well as the only one in the world located at latitude 19°N,in this work its current dimensions are updated,as well as the local climatology that governs the current state of the glacier is pointed *** study was based on the analysis of high-resolution Sentinel-2 optical images,as well as through Sentinel-1 SAR images,with the support of climatological information from the study ***,the outcropping of the bedrock in the accumulation zone and the consequent horizontal retreat of the upper part of the glacier are documented;at the same time,the decrease in the thickness of the ice along it is *** rocky outcrop in the accumulation zone suggests that the flow dynamics of the ice towards the ablation zone will be considerably less,accelerating the retreat of the glacier ***,the ascent of the glacial front to 5102 m *** the modelled altitude of the equilibrium line to 5276 m *** reported as a warning signal in terms of snow catchment and mass balance;likewise,the decrease of 23%of its surface is also indicated regarding the surface reduction monitoring that has been done

关键词： Bedrock outcrop Citlaltépetl glacier Glacial accumulation zone Glacier retreat Glacial thickness

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

Quantum information and microscopic measuring instruments

引用

Communications in Theoretical Physics 2020年第1期72卷 44-51页

作者： Alexey v Melkikh Ural Federal University YekaterinburgRussia

The consideration of measuring instruments as macroscopic bodies leads to neglect of the microscopic processes that occur during *** disregard is not justified in general *** an example of measurements using microscopic instruments,the scattering of a photon by an electron with electron interference at two slits(Compton effect)was *** amount of information that can be obtained in such a process is inversely proportional to the wavelength of the incident *** large photon wavelengths(soft measurements),the pure state of the electron can be disrupted by an arbitrarily small extent;accordingly,the amount of information extracted in such an experiment is also arbitrarily *** is shown that the energy price for a bit obtained in such a measurement tends toward a constant value for increasing the photon *** instruments can be used in situations where energy costs for measurements are important.

关键词： measurement problem double-slit experiment von Neumann entropy decoherence compton effect

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

Progress in ileal endogenous amino acid flow research in poultry

引用

Journal of Animal Science and Biotechnology 2021年第2期12卷 415-425页

作者： v.Ravindran Monogastric Research Centre School of Agriculture and EnvironmentMassey UniversityPalmerston North 4442New Zealand

The progress in our understanding of the endogenous protein concept over the past century is *** proteins found in the digesta at the terminal ileum of poultry,known as endogenous protein loss,are comprised of digestive secretions,mucus and sloughed gut epithelial *** measurement of this loss is of fundamental importance because it is an indicator of gut metabolism and is essential to adjust apparent estimates of ileal amino acid *** ileal endogenous amino acid losses comprise of two components,namely basal and specific *** basal losses are fixed and associated with feed dry matter intake,whereas the specific losses are variable and induced by the presence of dietary components such as fibre and *** there is no methodology available to directly measure the specific endogenous losses and these losses are calculated by determining the basal and total(basal plus specific)losses and,then subtracting the basal losses from total *** seminal features,specific applications and shortcomings of available methodologies are briefly outlined as well as the practical challenges faced in using the published endogenous amino acid loss values for true digestibility *** relevance of taurine as a component of endogenous protein flow in poultry is identified for the first time.

关键词： Basal loss Digestible amino acids Endogenous amino acid losses Poultry Specific loss

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

Active and passive modulation of solar light transmittance in a uniquely multifunctional dual-band single molecule for smart window applications

引用

Journal of Energy Chemistry 2024年第1期88卷 293-305,I0007页

作者： Pooja v.Chavan Pramod v.Rathod Joohyung Lee Sergei v.Kostjuk Hern Kim Department of Energy Science and Technology Environmental Waste Recycle InstituteMyongji UniversityYonginGyeonggi-do 17058Republic of Korea Department of Chemical Engineering Myongji UniversityYonginGyeonggi-do 17058Republic of Korea Research Institute for Physical Chemical Problems of the Belarusian State University MinskBelarus

Functional materials may change color by heat and electricity separately or simultaneously in smart *** materials have not only demonstrated remarkable potential in the modulation of solar radiation but are also leading to the development of indoor environments that are more comfortable and conducive to improving individuals'quality of ***,dual-responsive materials have not received ample research attention due to economic and technological *** a consequence,the broader utilization of smart windows faces *** address this new generational multistimulus responsive chromic materials,our group has adopted a developmental strategy to create a poly(NIPAM)n-Hv as a switchable material by anchoring active viologen(Hv)onto a phase-changing poly(NIPAM)n-based smart material for better utility and *** constructed smart windows facilitate individualistic reversible switching,from a highly transparent state to an opaque state(thermochromic)and a red state(electrochromic),as well as facilitate a simultaneous dual-stimuli response reversible switching from a clear transparent state to a fully opaque(thermochromic)and orange(electrochromic)*** privacy can be attained in smart windows designed for exclusive settings by achieving zero *** unique chromic mode operates independently and modulates visible and near-infrared(NIR)light in a distinct ***,these smart windows with thermal and electric dual-stimuli responsiveness demonstrate remarkable heat regulation capabilities,rendering them highly attractive for applications in building facades,energy harvesting,privacy protection,and color display.

关键词： Smart windows Thermochromism Electrochromism Energy saving Dual-responsive material

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

Structural traits of woody plants and geomorphological conditions to the vegetation recovery at Ksudach caldera(Southern Kamchatka) since the explosive eruption in 1907

引用

Journal of Mountain Science 2020年第7期17卷 1613-1635页

作者： KOPANINA Anna v LEBEDEvA Ekaterina v vLASOvA Inna I TALSKIKH Anastasia v Institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesNauka street1 B693022Yuzhno-SakhalinskRussia Institute of Geography Russian Academy of SciencesStaromonetny s-str.29119017MoscowRussia

This study considers the restoration of the plant cover destroyed by a catastrophic volcano eruption in the south of Kamchatka Peninsula(the Ksudach caldera,Shtyubel cone),with a particular attention to the role of woody *** aims to qualitatively estimate(at a qualitative level)the rate of the primary succession development depending on the microrelief and the modern relief-forming *** vegetation recovery in the caldera after the Shtyubel cone eruption 109 years ago proceeds slowly and *** proceeds most slowly on a thick tephra mantle continuously disturbed by water and wind erosion,lahars,debris flows,landslides,*** conditions are most typical of the western part of the caldera dominated by pumice fields with occasional patches of pioneer herbs and dwarf *** tundra communities with gradually expanding patches of shrub alder develop in the southern,eastern and northeastern parts of the Ksudach *** 1997 the area of the shrub alder communities has increased by 1.9 times,while the alpine tundra–by 1.3 times *** woody plants(dwarf shrubs and prostrate shrubs)are of particular importance in the process of the vegetation recovery on pumice *** suggest that the bark thickness of woody plants is an integrated indicator,which may serve for estimating the state of ecosystem in the course of the primary succession development on juvenile *** extremely inhospitable environments cause changes in physiological processes in the plant body and in its bark in *** results show that woody plants have a"thin"bark and develop some structural-functional arrangements for keeping bark tissues at their ***,the woody plant structure and the rate of changes in plant communities are under control of the geomorphic conditions and primarily–of physicochemical features of the pyroclastic cover.

关键词： Ksudach caldera Pioneer species Woody plants Bark Pyroclastic deposits Geomorphological processes

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

Modeling of Canonical Switching Cell Converter Using Genetic Algorithm

引用

Computer Modeling in Engineering & Sciences 2017年第1期113卷 109-116页

作者： T.v.viknesh v.Manikandan Department of Electrical and Electronics Engineering Coimbatore Institute of TechnologyCoimbatore-641014India

The working of Canonical switching cell(CSC)converter was studied and its equivalent circuit during ON and OFF states were *** space model of CSC converter in ON and OFF states were developed using the Kirchhoff *** state space matrices were used to construct the transfer functions of ON&OFF *** step response of the converter was simulated using *** step response curve was obtained using different values of circuit components(L,C1,C2 and RL)and *** characteristic parameters such as rise time,overshoot,settling time,steady state error and stability were determined using the step response *** response curve shows that there is no overshoot;the rise time and settling time are very low as expected for a converter and its stability is very high but the amplitude is *** circuit was tuned to attain the expected amplitude using PID controller with the help of Genetic *** excellent results of circuits’characteristic parameters are very useful guideline for constructing such CSC converters for DC-DC *** circuit characteristic parameters are useful in constructing such CSC converters for DCDC conversions in driving solar energy using solar panel.

关键词： Canonical switching cell converter state-space methods DC-DC converter step response stability power system modeling switching circuits genetic algorithm PID

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

On the asteroid-comet hazard mitigation problem for the earth

引用

Journal of Harbin Institute of Technology(New Series) 2003年第4期10卷 358-362页

作者： v v Ivashkin M v Keldysh Institute of Applied Mathematics

In frame of the asteroid-comet hazard problem study, a qualitative analysis of some methods for the effect on a celestial near-Earth object (NEO)-an asteroid, a comet — is carried out. The goal of the effect is a correction of this object’s orbit, its deflection from the Earth to prevent their collision. There are studied a mechanical impact-kinetic effect of the spacecraft (SC), a thermonuclear effect, an effect on a cometary nucleus for a controlled change of its dusty mantle and, therefore, its sublimation activity. Qualitative models of these effects are developed. Numerical analysis results are given for a group of NEOs such as some asteroids from the Apollo family (Apollo, Castalia, Nereus, Orpheus, Phaethon, Toutatis, etc.) and from the Aten family (Aten, Hathor, Khufu, etc.) as well as some short-periodic comets like the comet P/Biela. There are studied some characteristics of the effects on the NEOs such as the velocity impulse (or acceleration) applied to the celestial body, its deflection from the Earth. The study is supported by the Russian Foundation of Basic Studies (Grant N 01-01-00133).

关键词： hazard mitigation asteroid-comet hazard impact-kinetic effect

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

A review of the effects of dietary organic acids fed to swine

引用

Journal of Animal Science and Biotechnology 2016年第1期7卷 67-77页

作者： Mocherla v A N Suiryanrayna J v Ramana Livestock Research Station Sri Venkateswara Veterinary University

Animal production depends on nutrient utilization and if done there is an accelerated momentum towards growth with a low cost to feed ratio Public concern over the consumption of pork with antibiotic residues of the animals fed with antibiotic growth promoters （AGP） has paved the way to use other additives like herbs and their products, probiotics, prebiotics etc. Numerous feed additives are in vogue for achieving this target and one such classical example is the usage of organic acids and their salts. Usage of organic acids was in progress for over four decades. Early weaned piglets are （3-4 weeks age） exposed to stress with a reduced feed intake, little or no weight gain. This post weaning lag period is due to a limited digestive and absorptive capacity due to insufficient production of hydrochloric acid, pancreatic enzymes and sudden changes in feed consistency and intake. Lowering dietary pH by weak organic acids was found to overcome these problems. The main activity of organic acids is associated with a reduction in gastric pH converting the inactive pepsinogen to active pepsin for effective protein hydrolysis. Organic acids are both bacteriostatic and bactericidal. Lactic acid has been reported to reduce gastric pH and delay the multiplication of an enterotoxigenic E. coil These acids are the intermediary products in Kreb＇s cycle and thus act as an energy source preventing the tissue breakdown resulting from gluconeogenesis and lipolysis. Excretion of supplemental minerals and nitrogen are minimized with organic acids as these form complexes with minerals and aids for their bio-availability. Short chain fatty cids like acetic, propionic and n-butyric acid produced by microbial fermentation of dietary fibre in the large intestines may increase the proliferation of epithelial cells and have stimulatory effects on both endocrine and exocrine pancreatic secretions in pigs. Organic acids also enhances apparent total tract digestibility and improves growth performa

关键词： Chelation Improved productivity Organic acids Pathogen inhibition Protein utility Swine

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

Development of Mg-Zn-Y-Zr casting magnesium alloy with high thermal conductivity

引用

Journal of Magnesium and Alloys 2021年第5期9卷 1583-1593页

作者： v.E.Bazhenov A.v.Koltygin M.C.Sung S.H.Park Yu.v.Tselovalnik A.A.Stepashkin A.A.Rizhsky M.v.Belov v.D.Belov K.v.Malyutin National University of Science and Technology“MISiS” Leninskiy pr.4Moscow 119049 Russia LG Electronics Inc. Yeoui-daeroYeongdeungpo-gu.128LG Twin TowerSeoul 07336 Republic of Korea

Magnesium alloys are used in aircraft because of their light ***,for these alloys to be applied in electronic devices,high thermal conductivities are *** high-potential compositions of Mg-Zn-Y-Zr alloys were selected by phase composition and their freezing ranges calculated using Thermo-Calc *** alloys were prepared,and their fluidity,hot tearing susceptibility,mechanical properties,and thermal conductivity were obtained and *** alloy composed of Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr was selected for further investigation,because of its high thermal conductivity and satisfactory mechanical *** Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr alloy’s fluidity and hot tearing susceptibility were similar to those of the widespread AZ91 commercial casting magnesium *** influence of a heat treatment regime on the microstructure,thermal conductivity,and mechanical properties of the developed alloy was also *** was established that the room temperature thermal conductivity of the Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr alloy after aging at 300℃for 5 h was 105 W/m K^(-1).Additionally,the following tensile test results were obtained in aged condition:120 MPa yield strength,200 MPa ultimate tensile strength,and 4%*** utilization of solid solution heat treatment at 520℃for 8 h prior to aging can promote up to 9%increase in *** Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr casting alloy can be used as a high thermal conductivity material with industrial applications.

关键词： Magnesium alloy Mg-Zn-Y-Zr Thermal conductivity Phase composition Fluidity Hot tearing susceptibility

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：