检索结果-南通市图书馆

Experimental determination of gas holdup and volumetric mass transfer coefficient in a jet bubbling reactor

Chinese Journal of Chemical Engineering 2021年第6期34卷 61-67页

作者： mostafa Abbasian-arani mohammad Sadegh Hatamipour Amir Rahimi Chemical Engineering Department University of IsfahanIsfahanIran

The hydrodynamics and mass transfer characteristics of a lab-scale jet bubbling reactor(JBR)including the gas holdup,volumetric mass transfer coefficient and specific interfacial area were assessed experimentally investigating the influence of temperature,pH and superficial gas *** reactor diameter and height were 11 and 30 cm,*** was equipped with a single sparger,operating at atmospheric pressure,20 and 40℃,and two pH values of 3 and *** height of the liquid was 23 cm,while the superficial gas velocity changed within 0.010-0.040 m·s^(-1)*** were conducted with pure oxygen as the gas phase and saturated lime solution as the liquid *** liquid-side volumetric mass transfer coefficient was determined under unsteady-state oxygen absorption in a saturated lime *** gas holdup was calculated based on the liquid height change,while the specific interfacial area was obtained by a physical method based on the bubble size distribution(BSD)in different superficial gas *** results indicated that at the same temperature but different pH,the gas holdup variation was negligible,while the liquid-side volumetric mass transfer coefficient at the pH value of 6 was higher than that at the pH=*** a constant pH but different temperatures,the gas holdup and the liquid-side volumetric mass transfer coefficients at 40℃were higher than that of the same at 20℃.A reasonable and appropriate estimation of the liquid-side volumetric mass transfer coefficient(kla)in a pilot-scale JBR was provided which can be applied to the design and scale-up of JBRs.

关键词： Jet bubbling reactor Liquid-side volumetric mass transfer coefficient Gas holdup Specific interfacial area Experimental analysis

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

Accuracy of sedimentgraph modeling from topography map scale and DEm mesh size

引用

International Soil and Water Conservation Research 2019年第2期7卷 138-149页

作者： Seyed Hamidreza Sadeghi mostafa moradi Dashtpagerdi Hamidreza moradi Rekabdarkoolai Jeroen m.Schoorl Department of Watershed management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor 46417-76489MazandaranIran Department of Environmental Sciences Soil Geography and landscapeWageningen University and ResearchPO Box 47 6700AA WageningenThe Netherlands

The evaluation of scale effects on modeling performance of sedimentgraphs as the ultimate outputs of the hydrological simulation is vital for adaptive watershed *** present study therefore analyzed effectability of simulated sedimentgraphs components in association with different topographic maps with various vector *** whole procedure was materialized to select the critical scale and cell size for the Galazchai Watershed,*** this end,the stormwise sedimentgraphs were modeled for 23 recorded events using the Clark's Instantaneous Unit Hydrograph (IUH) model stemmed for developing Instantaneous Unit Sedimentgraphs (IUSGs) incorporated with dimensionless sediment concentTation distribution (DSCD) based on the vector scales of 1∶25000,1∶50000,1∶100000 and 1∶250000 and cell sizes of 5,10,20 30,50,100 and 200 *** 644 direct sedimentgraphs (DSGs) were then evaluated based on Relative Errors (REs) for sediment volume,peak sediment,time to peak,base time and the Coefficient of Efficiency (CE).The results confirmed that REs for peak sediment,time to peak and CE were sensitive to cell *** results further verified that the cell sizes of 5,20,30,50 and 100 m were critical cell sizes in viewpoint of time to *** addition,the vector scales of 1∶50000 with cell size of 50 m,and 1∶100000 with cell sizes of 5 and 10 m were critical vector scales and cell sizes based on RmSE evaluation *** is concluded from the current research that the accuracy of simulation of sedimentgraph was influenced by map scales and mesh sizes.

关键词： multiscale modeling Sedimentgraph variability Spatial Resolution Watershed simulation

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

Folded novel accurate analytical and semi-analytical solutions of a generalized Calogero–Bogoyavlenskii–Schiff equation

引用

Communications in Theoretical Physics 2021年第9期73卷 26-36页

作者： mostafa m A Khater S K Elagan m A El-Shorbagy S H Alfalqi J F Alzaidi Nawal A Alshehri Department of mathematics Faculty of ScienceJiangsu University212013ZhenjiangChina Department of mathematics Obour High Institute For Engineering and Technology11828CairoEgypt Department of mathematics Faculty of ScienceTaif University P.O.Box 11099Taif 21944Saudi Arabia Department of mathematics College of Science and Humanities in Al-KharjPrince Sattam bin Abdulaziz UniversityAl-Kharj 11942Saudi Arabia Department of Basic Engineering Science Faculty of EngineeringMenoufia UniversityShebin El-Kom 32511Egypt Department of mathematics Faculty of Science and ArtsMahayil Asir King Khalid UniversityAbhaSaudi Arabia

This paper studies the analytical and semi-analytic solutions of the generalized Calogero–Bogoyavlenskii–Schiff(CBS)*** model describes the(2+1)–dimensional interaction between Riemann-wave propagation along the y-axis and the x-axis *** extended simplest equation(ESE)method is applied to the model,and a variety of novel solitarywave solutions is *** solitary-wave solutions prove the dynamic behavior of soliton waves in *** accuracy of the obtained solution is verified using a variational iteration(VI)semi-analytical *** analysis and the match between the constructed analytical solution and the semi-analytical solution are sketched using various diagrams to show the accuracy of the solution we *** adopted scheme’s performance shows the effectiveness of the method and its ability to be applied to various nonlinear evolution equations.

关键词： generalized Calogero-Bogoyavlenskii-Schiff equation accurate analytical semianalytical solutions

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

monitoring and analysing the Emirate of Dubai’s land use/land cover changes:an integrated,low-cost remote sensing approach

引用

International Journal of Digital Earth 2018年第11期11卷 1132-1150页

作者： Samy Ismail Elmahdy mohamed mostafa mohameda Civil and Environmental Engineering Department College of Engineering United Arab Emirates UniversityAl-AinUnited Arab Emirates Irrigation and Hydraulics Department Faculty of EngineeringCairo UniversityGizaEgypt

This study presents a modified low-cost approach,which integrates the spectral angle mapper and image difference algorithms in order to enhance classification maps for the purpose of monitoring and analysing land use/land cover change between 2000 and 2015 for the Emirate of *** approach was modified by collecting 320 training samples from QuickBird images with a spatial resolution of 0.6 m,as well as carrying out field observations,followed by the application of a 3×3 Soble filter,sieving classes,majority/minority analysis,and clump classes of the obtained classification *** accuracy assessment showed that the targeted 2000,2005,2010 and 2015 classification maps have 88.1252%,89.0699%,90.1225%and 96.0965%accuracy,*** results showed that the built-up area increased by 233.721 km^(2)(5.81%)between 2000 and 2005 and continues to increase even up and till the present *** assessment of changes in the periods 2000–2005 and 2010–2015 confirmed that net vegetation area losses were more pronounced from 2000 to 2005 than from 2010 to 2015,dropping from 47,618 to 40,820 km^(2),*** study is aimed to assist urban planners and decision-makers,as well as research institutes.

关键词： Dubai change detection image difference SAm algorithm

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

Functional activity of the rectum:A conduit organ or a storage organ or both?

引用

World Journal of Gastroenterology 2006年第28期12卷 4549-4552页

作者： Ahmed Shafik Randa m mostafa Ismail Shafik Olfat EI-Sibai Ali A Shafik Department of Surgery and Experimental Research Faculty of MedicineCairo UniversityCairoEgypt Department of Physiology Faculty of MedicineSharkia UniversityBanha-ZagazigEgypt Department of Surgery Faculty of MedicineMenoufia UniversityShebin El-KomEgypt

AIm： To investigate whether the degree of rectal distension could define the rectum functions as a conduit mETHODS： Response of the rectal and anal pressure to 2 types of rectal balloon distension, rapid voluminous and slow gradual distention, was recorded in 21 healthy volunteers （12 men, 9 women, age 41.7 ± 10.6 years）. The test was repeated with sphincteric squeeze on urgent sensation. RESULTS： Rapid voluminous rectal distension resulted in a significant rectal pressure increase （P 〈 0.001）, an anal pressure decline （P 〈 0.05） and balloon expulsion. The subjects felt urgent sensation but did not feel the 1^st rectal sensation. On urgent sensation, anal squeeze caused a significant rectal pressure decrease （P 〈 0.001） and urgency disappearance. Slow incremental rectal filling drew a rectometrogram with a ＂tone＂ limb representing a gradual rectal pressure increase during rectal filling, and an ＂evacuation limb＂ representing a sharp pressure increase during balloon expulsion. The curve recorded both the ist rectal sensation and the urgent sensation. CONCLUSION： The rectum has apparently two functions： transportation （conduit） and storage, both depending on the degree of rectal filling. If the fecal material received by the rectum is small, it is stored in the rectum until a big volume is reached that can affect a degree of rectal distension sufficient to initiate the defecation reflex. Large volume rectal distension evokes directly the rectoanal inhibitory reflex with a resulting defecation.

关键词： Anal pressure Rectal pressure Rectometry First rectal sensation

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

The effect of maternal thyroxine injection on growth, survival and development of the digestive system of Nile tilapia, <i>Oreochromis niloticus</i>, larvae

引用

Advances in Bioscience and Biotechnology 2011年第5期2卷 320-329页

作者： Noha A. Khalil hassan m. m. Khalaf Allah mostafa A. mousa 不详

The present study deals with the effect of exogenous treatment of O. niloticus females with L-thyroxine (T4) on the development of the digestive system during larval rearing, and its subsequent effect on larval growth and survival. The development of the digestive tract and accessory glands was investigated histologically and histochemically in the developing O. niloticus larvae, from control and T4-treated spawners. During yolk-sac absorption, the digestive system of the fish underwent further differentiation and the rudimentary alimentary canal became segmented into four different histological regions: the buccopharynx, oesophagus, stomach and intestine. The injection of females O. niloticus with thyroxine (1 or 10 μg T4/g BW) greatly enhanced the development of the digestive tract and accessory glands of larvae as indicated by the quantitative and qualitative changes of the mucus composition from predominantly neutral to a mixture of neutral and acid mucosubstances, or acid mucosubstances occurred during the rearing period for the larvae produced from T4-treated females. This may be due to the direct effect of exogenous thyroxine, which might have been transferred from maternal circulation into the oocytes and larvae, on the synthesis of proteins, which increased with larval development. Thus, thyroxine directly or indirectly improved O. niloticus larval growth, since a marked increase in both, length and weight of larvae occurred during the experimental period. In addition, larvae from treated females also gave a significantly higher survival rate than that of control. It could be concluded that exogenous T4 in maternal circulation might have been transferred into oocytes and larvae. The transferred thyroid hormone appears to play some role in the early development of larvae and may confer a distinct advantage for the growth of the offspring of the Nile tilapia, O. niloticus.

关键词： Fish Larvae O. Niloticus Thyroxine Growth Digestive System

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

Optimization of the fully grouted rock bolts for load transfer enhancement

引用

International Journal of mining Science and Technology 2015年第5期25卷 707-712页

作者： Ghadimi mostafa Shahriar Korosh Jalalifar Hossein Department of mining Engineering Tehran Science and Research BranchIslamic Azad University Faculty of mining Metallurgy and Petroleum EngineeringAmir Kabir University of Technology Department of Petroleum and mining Engineering Environmental and Energy Research CenterShahidBahonar University of Kerman

The purpose of this study is to investigate the role of bolt profile configuration in load transfer capacity between the bolt and ***,five types of rock bolts are used with different *** rock bolts are modeled by ANSYS *** show that profile rock bolt T_3 and T_ with load capacity 180 and 195 kN in the jointed rocks,are the optimum ***,the performances of the selected profiles are examined in Tabas Coal mine by FLAC *** is good subscription between the results of numerical modeling and instrumentation reading such as tells tale,sonic extensometer and strain gauge rock *** to the finding of this study,the proposed pattern of rock bolts,on 7 + 6 patterns per meter with 2 flexi bolt(4 m) for support gate road.

关键词： Fully grouted rock bolts Numerical modeling Load transfer Bolt profile

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

Spatial downscaling of climate variables using three statistical methods in Central Iran

引用

Journal of mountain Science 2018年第3期15卷 606-617页

作者： Zahra JABERALANSAR mostafa TARKESH mehdi BASSIRI Department of Natural Resources Isfahan University of Technology Research Division of Natural Resources Isfahan Agricultural and Natural Resources Research and Education CenterAREEO

Spatial downscaling methods are widely used for the production of bioclimatic variables(e.g. temperature and precipitation) in studies related to species ecological niche and drainage basin management and planning. This study applied three different statistical methods, i.e. the moving window regression(mWR), nonparametric multiplicative regression(NPmR), and generalized linear model(GLm), to downscale the annual mean temperature(Bio1) and annual precipitation(Bio12) in central Iran from coarse scale(1 km × 1 km) to fine scale(250 m ×250 m). Elevation, aspect, distance from sea and normalized difference vegetation index(NDVI) were used as covariates to create downscaled bioclimatic variables. model assessment was performed by comparing model outcomes with observational data from weather stations. Coefficients of determination(R2), bias, and root-mean-square error(RmSE) were used to evaluate models and covariates. The elevation could effectively justify the changes in bioclimatic factors related to temperature and precipitation. Allthree models could downscale the mean annual temperature data with similar R2, RmSE, and bias values. The mWR had the best performance and highest accuracy in downscaling annual precipitation(R2=0.70; RmSE=123.44). In general, the two nonparametric models, i.e. mWR and NPmR, can be reliably used for the downscaling of bioclimatic variables which have wide applications in species distribution modeling.

关键词： Statistical models Climatic data Elevation Spatial resolution Temperature Precipitation

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

Joint Optimal Power Source Sizing and Data Collection Trip Planning for Advanced metering Infrastructure Enabled by Unmanned Aerial Vehicles

引用

Journal of modern Power Systems and Clean Energy 2022年第5期10卷 1337-1348页

作者： Haiam Shahin mostafa F.Shaaban mahmoud H.Ismail Hebat-Allah m.mourad Ahmed Khattab Department of Electronics and Communications Engineering Facultyof EngineeringCairo UniversityGiza 12613Egypt IEEE Department of Electrical Engineering American University of SharjahPOBox 26666SharjahThe United Arab Emirates

The use of unmanned aerial vehicles(UAVs) in the collection of data from wireless devices, sensor nodes, and the Internet of Things(IoT) devices has recently received significant attention. In this paper, we investigate the data collection process from a set of smart meters in advanced metering infrastructure(AmI) enabled by UAVs. The objective is to minimize the total annual cost of the electric utility by jointly optimizing the number of UAVs, their power source sizing, the charging locations as well as the data collection trip planning. This is achieved while considering the energy budgets of batteries of UAVs and the required amount of collected data. The problem is formulated as a mixed-integer nonlinear programming(mINLP), which is decoupled into two sub-problems where a candidate UAV and a number of buildings are first grouped into trips via genetic algorithms(GAs), and then the optimum trip path is found using a traveling salesman problem(TSP) branch and bound algorithm. Simulation results show that the battery capacity or the number of UAVs increases as the coverage area or the density increases.

关键词： Advanced metering infrastructure unmanned aerial vehicle power source sizing trip planning genetic algorithm

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 study of power production from tidal energy in the Khuran Channel and its feedback on background hydrodynamics

引用

Acta Oceanologica Sinica 2022年第5期41卷 173-182页

作者： Davood Shariatmadari Seyed mostafa Siadatmousavi Cyrus Ershadi Civil Engineering Department Faculty of Technology and EngineeringUniversity of HormozganHormozganBandar Abbas***Iran School of Civil Engineering Iran University of Science and TechnologyTehran***Iran

This study focuses on the development of a farm of tidal turbines in the Khuran *** important factors include the location of turbines and their hydrodynamic effects on the environment.A three-dimensional circulation model for the Persian Gulf is employed for the comprehensive evaluation of the tidal energy potential throughout the study *** model is validated by using in situ observations of water level and current *** appropriate potential points for extracting the tidal energy were identified in the Persian Gulf using the model *** Khuran Channel,located in the north of Qeshm Island,was found to be the best place to extract tidal energy inside the Persian *** adding the term of momentum losses to the governing equations,the feedback of extracting energy on the hydrodynamic around Qeshm Island was *** simulation results show that the average daily power production of a tidal farm with 99 turbines for one month is approximately 1.3 *** tidal farm also has a significant impact on the water level inside the Khuran Channel,especially near the tidal farm where these fluctuations exceed 4 *** change in the current speed caused by wake reaches 0.4 m/*** effects were active up to 7 km downstream of the *** current velocity was also estimated to be 1.6 m/s and 2.1 m/s during the spring and ebb tides within the channel,respectively.

关键词： renewable energy tidal energy Khuran Channel tidal horizontal axis turbine turbine farm Delft3D

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：