检索结果-南通市图书馆

Breaking seed dormancy in Cupressus atlantica Gaussen,an endemicand threatened coniferous tree in Morocco

Journal of Forestry Research 2012年第3期23卷 385-390页

作者： Sfairi Youssef Ouahmane Lahcen abbad abdelaziz Direction Provinciale des Eaux et Forets et de la lutte contre laDésertification MarrakechMaroc Laboratoire de Biotechnologies Protection et Valorisation des Ressources Végétalesdépartement deBiologieEquipe de Phytochimie et Pharmacologie des Plantes Aromatiques et MédicinalesFacultédes Sciences SemlaliaUniversitéCadi AyyadMarrakechMaroc Centre Régional de Recherche Forestière Circuit de la PalmeraieMarrakechMaroc Laboratoire de Biotechnologies Protection et Valorisation desRessources Végétalesdépartement de BiologieEquipe de Phytochimieet Pharmacologie des Plantes Aromatiques et MédicinalesFacultédesSciences SemlaliaUniversitéCadi AyyadMarrakechMaroc

Cupressus atlantica Gaussen （Cupressaceae） is an endemic and endangered coniferous tree geographically restricted to the N＇Fis valley in South-Western Morocco. Like many forest species, C. atlantica exhibits dormancy which delays and reduces germination. To improve seed germination, different pre-treatments were conducted on C. atlantica seeds after storage for different periods （one, two and five years） including： scarification with sandy paper; soaking seeds in hot distilled water at 60℃ and 80℃ for 15 min and soaking seeds for 48 h in a gibberellic acid （GA3） at 1,000 and 2,000 mg·L-1. Results showed that scarification with sandy paper increased the germination rate of Atlas cypress by up to 67%, indicating that the species possess essentially an exogenous dormancy （physical dormancy） due to the hard seed coat （hardseededness）. Exogenous application of gibberellic acid （GA3） at 1,000 mg.L-1 was also effective in breaking seed dormancy and germination induction. These two treatments induced faster speed germination expressed by low number of days to first germination （8-10 days） and low values of mean germination times （MGT）. However, germination rate, under any treatment, is greatly dependent on the year of seed collection. Seeds collected in year 2004 gave the highest value, suggesting that even after five years of storage, the germination capacity of C. atlantica seeds could remain high. This observation is very interesting in the ex-situ conservation of such endemic and endangered species where the production of seeds is irregular over the years.

关键词： Cupressus atlantica endemic endangered breaking seed dormancy germination capacity hand scarification ex-situ conservation

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 fiber bridging in fluid flow for well stimulation applications

引用

Petroleum Science 2020年第3期17卷 671-686页

作者： Mehdi Ghommem Mustapha abbad Gallyam Aidagulov Steve Dyer Dominic Brady Department of Mechanical Engineering American University of ShaijahSharjah 26666United Arab Emirates Schlumberger Dhahran Carbonate Research Center Dammam/Doha Camp 31942Kingdom of Saudi Arabia Schlumberger Completions RosharonTX 77583USA

Accurate acid placement constitutes a major concern in matrix stimulation because the acid tends to penetrate the zones of least resistance while leaving the low-permeability regions of the formation *** materials(fibers and solid particles)have recently shown a good capability as fluid diversion to overcome the issues related to matrix *** the success achieved in the recent acid stimulation jobs stemming from the use of some products that rely on fiber flocculation as the main diverting mechanism,it was observed that the volume of the base fluid and the loading of the particles are not *** current industry lacks a scientific design guideline because the used methodology is based on experience or empirical studies in a particular area with a particular *** is important then to understand the fundamentals of how acid diversion works in carbonates with different diverting mechanisms and *** modeling and computer simulations are effective tools to develop this understanding and are efficiently applied to new product development,new applications of existing products or usage *** this work,we develop a numerical model to study fiber dynamics in fluid *** employ a discrete element method in which the fibers are represented by multi-rigid-body systems of interconnected *** discrete fiber model is coupled with a fluid flow solver to account for the inherent simultaneous *** focus of the study is on the tendency for fibers to flocculate and bridge when interacting with suspending fluids and encountering restrictions that can be representative of fractures or wormholes in *** trends of the dynamic fiber behavior under various operating conditions including fiber loading,flow rate and fluid viscosity obtained from the numerical model show consistency with experimental *** present numerical investigation reveals that the bridging capability of the fi

关键词： Fiber bridging Fiber flocculation Modeling and numerical simulation Discrete element method Fiber-fluid coupling Sensitivity 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

Simultaneous removal of Congo red and cadmium(Ⅱ) from aqueous solutions using graphene oxide–silica composite as a multifunctional adsorbent

引用

Journal of Environmental Sciences 2020年第12期32卷 151-160页

作者： Ebrahim Mahmoudi Sepehr Azizkhani Abdul Wahab Mohammad Law Yong Ng Abdelbaki Benamor Wei Lun Ang Muneer Ba-abbad Department of Chemical and Process Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia43600 BangiSelangor Darul EhsanMalaysia Department of Chemical and Environmental Engineering Faculty of EngineeringUniversiti Putra Malaysia43400 SerdangSelangorMalaysia Department of Chemical Engineering Lee Kong Chian Faculty of Engineering and ScienceUniversiti Tunku Abdul RahmanJalan Sungai LongBandar Sungai LongCheras43000 KajangSelangorMalaysia Centre for Sustainable Process Technology(CESPRO) Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia43600 BangiSelangor Darul EhsanMalaysia Gas Processing Centre Qatar UniversityP.O.Box 2713DohaQatar

Graphene oxide is a very high capacity adsorbent due to its functional groups and π-π interactions with other compounds. Adsorption capacity of graphene oxide, however, can be further enhanced by having synergistic effects through the use of mixed-matrix composite. In this study, silica-decorated graphene oxide(SGO) was used as a high-efficiency adsorbent to remove Congo red(CR) and Cadmium(Ⅱ) from aqueous solutions. The effects of solution initial concentration(20 to 120 mg/l), solution pH(pH 2 to 7), adsorption duration(0 to 140 min) and temperature(298 to 323 K) were measured in order to optimize the adsorption conditions using the SGO adsorbent. Morphological analysis indicated that the silica nanoparticles could be dispersed uniformly on the graphene oxide surfaces. The maximum capacities of adsorbent for effective removal of Cd(Ⅱ) and CR were 43.45 and 333.33 mg/g based on Freundlich and Langmuir isotherms, respectively. Langmuir and Freundlich isotherms displayed the highest values of Q max for CR and Cd(Ⅱ) adsorption in this study, which indicated monolayer adsorption of CR and multilayer adsorption of Cd(II) onto the SGO, respectively. Thermodynamic study showed that the enthalpy( H) and Gibbs free energy( G) values of the adsorption process for both pollutants were negative, suggesting that the process was spontaneous and exothermic in nature. This study showed active sites of SGO( π-π, hydroxyl, carboxyl, ketone, silane-based functional groups) contributed to an enormous enhancement in simultaneous removal of CR and Cd(Ⅱ) from an aqueous solu-tion, Therefore, SGO can be considered as a promising adsorbent for future water pollution control and removal of hazardous materials from aqueous solutions.

关键词： Graphene-oxide Multifunctional adsorbent Competitive removal Heavy metal-dye removal

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

船舶减摇水舱试验台不同控制策略的比较研究

船舶减摇水舱试验台不同控制策略的比较研究

引用

作者： Redhouane abbad 哈尔滨工程大学

学位级别：硕士

船舶在海上航行时，由于受到海浪、海风及海流等海洋环境扰动的作用，不可避免地要产生六自由度运动，即横摇、纵摇、首摇、横荡、升沉和纵荡运动。横摇运动过大不但影响船舶的航行，而且还会对船舶上的装备带来不良影响，对船上货物和... 详细信息

船舶在海上航行时，由于受到海浪、海风及海流等海洋环境扰动的作用，不可避免地要产生六自由度运动，即横摇、纵摇、首摇、横荡、升沉和纵荡运动。横摇运动过大不但影响船舶的航行，而且还会对船舶上的装备带来不良影响，对船上货物和人员带来不安全因素。因为船舶的横摇运动阻尼很小，横摇运动是船舶主要运动形式，在特定频率海浪干扰下的横摇运动将非常剧烈。船舶设计师和控制工程师一直致力于研制有效的减摇装置来减小船舶的横摇运动，提高船舶的耐波性能。在众多减摇装置中，减摇水舱因其结构简单、成本低并在零航速具有减摇能力等优点被广泛应用。为降低研究和设计成本，建立减摇水舱的试验装置是对减摇水舱进行研究的重要手段。船舶减摇水舱实验台架是二自由度系统，对于研究和设计减摇水舱有重要作用。在中国仅有少数几家单位建立减摇水舱实验台架。它可以模拟实际舰船在海浪中的运动，从而为研究减摇水舱对船舶的作用，评估其减摇效果，为设计和研究减摇水舱提供了可靠的依据。为模拟实时海浪运动，要求控制系统具有较高的频率响应，电液伺服系统因其响应快、传递功率大等特点被作为系统的执行机构。实验台架的性能主要取决于二方面：一是电液伺服系统关键部件的选择，例如伺服放大器、执行油缸和运动传感器;二是制定合理的控制策略。对于给定实船模型，实验台架性能主要取决于控制策略。本文通过分析减摇水舱实验台架运动特性，设计出合理的控制策略，并通过仿真验证控制器控制性能。文中分析设计了极点配置控制器、非线性控制器和许多新型智能控制器，并将其与传统PID控制器相比较，验证控制效果。由于滑模控制对于非线性系统和外部扰动具有很强的自适应能力，本文设计了基于滑模控制的控制器。此外，基于模糊集和模糊推理的模糊控制在文中进行了详细的分析，并设计模糊控制器。在正弦波海浪信号和随机海浪信号输入下，对控制器进行仿真。结果表明，滑模控制器和模糊控制器控制效果优于传统PID控制器。

关键词：船舶水舱试验台架 PID控制极点配置滑模控制模糊控制线性和非线性控制

来源：

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Glutamate and Caffeine intake of Some Snacks and Drinks in Saudi Arabia

引用

Food and Nutrition Sciences 2011年第2期2卷 162-167页

作者： Magda I. Hassan Najat A. Al-abbad 不详

The aim of this study was to estimate the intake level of glutamate and caffeine from some snacks and drinks. The survey was carried out during 2008 to 2009 in 3 selected governorates (Al-Hassa, Al- Katif and AD-Dammam) localized in the eastern area of Saudi Arabia. The age of study participants (298) was ranged between less than 4 – over 30 years. The snacks and drinks consumption data were gathered and calculated using the frequency methods. Forty nine samples of snacks and beverages were analyzed by High Performance Liquid Chromatography (HPLC) for glutamate and caffeine contents. The results indicated that total intake of snacks, chocolates and drinks were significantly correlated (spearman r = 0.856, 0.591, 0.943, p = 0.0) with total intake of glutamate and caffeine. The mean of caffeine intake was 40.4± 44.5 mg, while the mean of glutamate intake was 0.134± 0.146 mg. The highest concentration of glutamate was in Pringles with Ketchup (0.420), Bugles Smoking BBQ (0.660) and Indomie with Vegetables (0.860). The high caffeine concentrations of Kit Kat, Ulker and Galaxy samples were 166, 165.5, and 134.5 mg/kg respectively, while the beverages, the high caffeine concentrations were presented in energy drinks like Red bull (345.5), Power Horse (339.0) and Bugzy(333.0) mg/L. The children aged between 4– 8 were the most consumers of snacks which containing glutamate, while the adolescents consumed more chocolates and beverages which containing caffeine. These finding suggests that consumption of salty snacks, and sugar-sweetened beverages is mounting between important categories in the community, so interventions focusing on increasing physical activity and fruit and vegetable consumption will have an impact on obesity control and promoting health.

关键词： Glutamate Caffeine Snacks Eating Habits Drinks KSA HPLC

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

Cellular based treatment modalities for unresectable hepatocellular carcinoma

引用

World Journal of Clinical Oncology 2021年第5期12卷 290-308页

作者： Konstantinos Damiris Hamza abbad Nikolaos Pyrsopoulos Department of Medicine Rutgers New Jersey Medical SchoolNewarkNJ 07103United States Department of Medicine Division of Gastroenterology and HepatologyRutgers New Jersey Medical SchoolNewarkNJ 07103United States

Hepatocellular carcinoma(HCC)is the most common primary malignancy of the liver and is unfortunately associated with an overall poor prognosis and high *** and intermediate stages of HCC allow for treatment with surgical resection,ablation and even liver transplantation,however disease progression warrants conventional systemic *** years treatment options were limited to molecular-targeting medications,of which sorafenib remains the standard of *** recent development and success of immune checkpoint inhibitors has proven to be a breakthrough in the treatment of HCC,but there is an urgent need for the development of further novel therapeutic treatments that prolong overall survival and minimize *** investigation is focused on adoptive cell therapy including chimeric antigen receptor-T cells(CAR-T cells),T cell receptor(TCR)engineered T cells,dendritic cells,natural killer cells,and tumor infiltrating lymphocyte cells,which have shown remarkable success in the treatment of hematological and solid tumor *** this review we briefly introduce readers to the currently approved systemic treatment options and present clinical and experimental evidence of HCC immunotherapeutic treatments that will hopefully one day allow for revolutionary change in the treatment modalities used for unresectable *** also provide an up-to-date compilation of ongoing clinical trials investigating CAR-T cells,TCR engineered T cells,cancer vaccines and oncolytic viruses,while discussing strategies that can help overcome commonly faced challenges when utilizing cellular based treatments.

关键词： Hepatocellular carcinoma Immunotherapy Immune cells Adoptive T cell therapy Chimeric antigen receptor-T cell Clinical trials

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

A Short Review of Classification Algorithms Accuracy for Data Prediction in Data Mining Applications

引用

Journal of Data Analysis and Information Processing 2021年第3期9卷 162-174页

作者： Ibrahim Ba’abbad Thamer Althubiti Abdulmohsen Alharbi Khalid Alfarsi Saim Rasheed Department of Information Technology Faculty of Computing and Information Technology King Abdulaziz University Jeddah KSA

Many business applications rely on their historical data to predict their business future. The marketing products process is one of the core processes for the business. Customer needs give a useful piece of information that helps to market the appropriate products at the appropriate time. Moreover, services are considered recently as products. The development of education and health services is depending on historical data. For the more, reducing online social media networks problems and crimes need a significant source of information. Data analysts need to use an efficient classification algorithm to predict the future of such businesses. However, dealing with a huge quantity of data requires great time to process. Data mining involves many useful techniques that are used to predict statistical data in a variety of business applications. The classification technique is one of the most widely used with a variety of algorithms. In this paper, various classification algorithms are revised in terms of accuracy in different areas of data mining applications. A comprehensive analysis is made after delegated reading of 20 papers in the literature. This paper aims to help data analysts to choose the most suitable classification algorithm for different business applications including business in general, online social media networks, agriculture, health, and education. Results show FFBPN is the most accurate algorithm in the business domain. The Random Forest algorithm is the most accurate in classifying online social networks (OSN) activities. Naïve Bayes algorithm is the most accurate to classify agriculture datasets. OneR is the most accurate algorithm to classify instances withi

关键词： Data Prediction Techniques Accuracy Classification Algorithms Data Mining Applications

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

Time Series Analysis and Forecasting of the Air Quality Index of Atmospheric Air Pollutants in Zahleh, Lebanon

引用

Atmospheric and Climate Sciences 2022年第4期12卷 728-749页

作者： Alya Atoui Kamal Slim Samir abbad Andaloussi Régis Moilleron Zaher Khraibani Leesu Univ Paris Est Creteil Creteil France Rammal Rammal Laboratory PhyToxE Group Lebanese University Nabatieh Lebanon Lebanese Atomic Energy Commission National Council for Scientific Research (CNRS) Beirut Lebanon Department of Applied Mathematics Faculty of Sciences Lebanese University Hadat Lebanon

During the last decades, air pollution has become a serious environmental hazard. Its impact on public health and safety, as well as on the ecosystem, has been dramatic. Forecasting the levels of air pollution to maintain the climatic conditions and environmental protection becomes crucial for government authorities to develop strategies for the prevention of pollution. This study aims to evaluate the atmospheric air pollution of the city of Zahleh located in the geographic zone of Bekaa. The study aims to determine a relationship between variations in ambient particulate concentrations during a short time. The data was collected from June 2017 to June 2018. In order to predict the Air Quality Index (AQI), Naïve, Exponential Smoothing, TBATS (a forecasting method to model time series data), and Seasonal Autoregressive Integrated Moving Average (SARIMA) models were implemented. The performance of these models for predicting air quality is measured using the Mean Absolute Error (MAE), the Root Mean Square Error (RMSE), and the Relative Error (RE). SARIMA model is the most accurate in prediction of AQI (RMSE = 38.04, MAE = 22.52 and RE = 0.16). The results reveal that SARIMA can be applied to cities like Zahleh to assess the level of air pollution and to prevent harmful impacts on health. Furthermore, the authorities responsible for controlling the air quality may use this model to measure the level of air pollution in the nearest future and establish a mechanism to identify the high peaks of air pollution.

关键词： Air Pollution Air Quality Index Times Series Prediction

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

Multivariate Spatial and Temporal Analysis to Study the Variation of Physico-Chemical Parameters in Litani River, Lebanon

引用

American Journal of Analytical Chemistry 2021年第11期12卷 373-391页

作者： Ali Hayek Samir abbad Andaloussi Nabil Tabaja Joumana Toufaily Evelyne Garnie-Zarli Tayssir Hamieh Laboratory of Materials Catalysis Environment and Analytical Methods Laboratory (MCEMA) EDST FS Lebanese University Hadath Lebanon Laboratory of Applied Studies for Sustainable Development and Renewable Energy (LEADDER) EDST Lebanese University Hadath Lebanon Laboratoire Sol Eau Systèmes Urbains (LEESU) Université Gustave Eiffel Paris France Faculty of Science and Engineering Maastricht University Maastricht Netherlands

Water quality of Litani River was deteriorated due to rapid population growth and industrial and agricultural activity. Multivariate analysis of spatio-temporal variation of water quality is useful to improve the projects of water quality management and treatment of the river. In this work, analysis of samples from different locations at different seasons was investigated. The spatio-temporal variation of physico-chemical parameters of the water was determined. A total of 11 water quality parameters were monitored over 12 months during 2018 at 3 sites located in different areas of the river. Multivariate statistical techniques were used to study the spatio-temporal evolution of the studied parameters and the correlation between the different factors. Principal Component Analysis (PCA) was applied to the responsible factors for water quality variations during wet and dry periods. The multivariate analysis of variance (MANOVA) was also applied to the same factors and gives the best results for both spatial and temporal analysis. A black point of agricultural, industrial and sewage water pollution was identified in Jeb-Jennine station from the high concentrations of ammonia, sulfate and phosphate. This difference was proved by the major changes in the values of the parameters from one station to the other. Jeb-Jennine represents a main pollution area in the river. The high ammonia, sulfate and phosphate concentrations result from the important agricultural, industrial and sewage water pollution in the area. A high bacterial activity was highlighted in Jeb-Jennine and Quaroun stations because of the presence of the high nitrite concentrations in the two locations. All parameters are highly affected by climate factors, especially temperature and precipitation. TDS, salinity, electrical conductivity and the concentrations of all pollutants increase during wet season affected by the runoff. Other factors can affect the water quality of the river for example geographical fe

关键词： Water Quality Litani River Principal Component Analysis Seasonal Variation Spatial Variation

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

Evaluation of the Physico-Chemical Properties of the Waters on the Litani River Station Quaraoun

引用

American Journal of Analytical Chemistry 2020年第2期11卷 90-103页

作者： Ali Hayek Nabil Tabaja Samir abbad Andaloussi Joumana Toufaily Evelyne Garnie-Zarli Abbas El Toufaili Tayssir Hamieh Laboratory of Materials Catalysis Environment and Analytical Methods Laboratory (MCEMA) EDST FS Lebanese University Hadath Lebanon Laboratory of Applied Studies for Sustainable Development and Renewable Energy (LEADDER) EDST Lebanese University Hadath Lebanon Laboratoire Sol Eau Systèmes Urbains (Leesu) Université Paris Est Paris France

Water security is a very important purpose facing the world in the last decay as one of the main consequences related to the risks of climate change. Water quality of Litani River’s at Quaraoun Lake station in Lebanon was evaluated by measuring various physicochemical parameters between 2008 and 2018. Samples were performed and analyzed the first of every month. Different analytical methods were used to determine the values of 11 physico-chemical parameters. Different statistical methods, such as Principal Component Analysis and the Times Series Representation, were applied to the results to evaluate the water characteristics, determine the operation of the ecosystem and study the correlation between the different parameters in the Quaraoun station. Industrial, agricultural and sewage water pollution of the Litani River were demonstrated by the high concentration of sulfate, phosphate and ammonia. High bacterial activity was proved from the high decreasing of the dissolved oxygen. Important correlations between the different parameters and between the parameters of the ecosystem and the weather were proved.

关键词： Litani River Water Characteristics Physico-Chemical Parameters Statistical Analysis

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

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：