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Biological Status of Indus River Dolphin （Platanista Minor Owen） in Indus River, Northern Pakistan

Journal of Life Sciences 2011年第1期5卷 39-47页

作者： Farzana Perveen Sardar Azher Mehmood Shabbir ahmed Zia Ur Reman Department of Zoology Hazara University Garden Campus Mansehra-21300 Pakistan

A study was aimed to determine the biological status of the Indus river dolphin, Platanista minor Owen in Indus river with respect to distribution, threats and protection throughout its range in Northern Pakistan. For this purpose, a survey was conducted in an area of 103.5 km including the Indus river and its tributaries in March 2009 for estimating its distribution and population size using both direct observations of the dolphin as well as indirect evidences from its signs. The best group size was estimated with an abundance of 54 dolphins. Approximately 53.7% （1.07 dolphin＆m） of the dolphin-population occurred in 27 km from Miran onward to Ramak, however, 38.9% （0.46 dolphin/km） occurred in 46 km from Dera ismail （D.I.） Khan bridge to Miran, moreover, 7.4% （0.13 dolphin/kin） occurred in 30.5 km from Saggu, near Meetapur-village to D.I. Khan bridge in the Indus river. The highest density was found between Miran and Ramk. A pronounced increase in dolphin encounter rate and abundance were observed in a downstream-direction. Threats to dolphins include too much vessel-traffic, disturbance by the crane, duck-hunters, and no effective-protection. Dolphins are particularly vulnerable to the high levels of anthropogenic activities because of their restricted habitat. Threats vary geographically in their importance, but generally include accidental killing during fishing-operations, habitat-loss and population-fragmentation from water development. Deliberate killing for dolphin products also threatens the dolphins. Potential for protections and possibilities for dolphin eco-tourism measures must be taken.

关键词： Dolphin endangered or critically endangered Indus river Northern Pakistan protection population.

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Report on the Diatoms and Dinoflagellates Distribution along the Algerian Coasts: Inter-Region Comparison

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Journal of Resources and Ecology 2019年第4期10卷 432-440页

作者： Zakia MOKRANE Mustapha BOUDJENAH Yasmina BELKACEM EL Hadi MORSLI ahmed INAL Fahima BOUARAB National Center for Research and Development of Fisheries and Aquaculture (CNRDPA)/ Bou-ismail Tipaza 42415 Algeria FSB-USTHB/ Pelagic ecosystem laboratory Algiers No 32 El-Alia Bab Ezzouar 16111 Algeria Department of Marine Sciences Faculty of Natural and Life Sciences Abdelhamid Ibn Badis University of Mostaganem P. 300 Algeria

The phytoplankton group’s composition is an excellent indicator of the state of coastal waters. The aim of this study is to explore spatial variability of phytoplankton in shallow coastal areas from different regions(East, Center and West) of the Algerian coast. The quantitative and qualitative study of the phytoplankton population was conducted on samples taken during the 2012–2013 period by the research vessel GRINE BELKACEM. The qualitative results show a significant diversity of diatoms and dinoflagellates, which rank first and second in the total flora(Fr > 50%). This finding is also confirmed quantitatively by the abundance values in both 2013 and 2012 samples which largely exceeds the average value in most other areas of the western region(56%) and slightly exceeding 52% in all central areas which represent an equi-distribution between diatoms and dinoflagellates. The Dinoflagellates contribute significantly to the quantitative richness in the eastern region(>60%). The minimum value of Dia/Dino index, recorded in the eastern region confirms the dominance of the dinoflagellates especially in Skikda(0.31)(Skikda).However, our results reveal the presence, in smaller proportion, of other groups such as the cocolithophoridae and euglenophyceae.

关键词： Phytoplankton composition Dia/Dino index Algerian coast

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Physical Characterization and Elaboration Discussion of a Clay-PEG 6000 Composite with Natural Clay Matrix

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Engineering（科研） 2014年第7期6卷 338-354页

作者： Iatimad Akhrif Mostapha El Jai Laila Mesrar ahmed Elkhalfi Abdelhamid Touache Raouf Jabrane Advanced Material and Application Team Ecole Nationale Supérieure d’Arts et Métiers de Meknès Moulay Ismail University Meknes Morocco Geosciences and Environment Laboratory Faculty of Sciences and Techniques Sidi Mohammed Ben Abdellah University Fez Morocco Mechanical Engineering Department Faculty of Sciences and Techniques Sidi Mohammed Ben Abdellah University Fez Morocco

In this paper, we compare different nanoclay-PEG composites and the influence of the input parameters especially the percentage of PEG and the clay size. Because of the facility of material elaboration, dried state with grinding, we adopted a complete experiments plan to obtain a maximum of robustness of the responses. For each sample, we made an XRD analysis to see if we obtain the intercalation of the PEG 6000 (Polyethylene Glycol 6000) within the clay sheets. The characterization adopted consists on the measurement of the shrinking of some cylinders we made, the liquidity and plasticity limits according to the Casagrande protocol used in geotechnical clays characterizations. We utilize also the methylen blue protocol to estimate the variation of the specific surface of ionic exchange of the clay sheets according to the PEG 6000 percentage and the clay sizes. SEM microscopy permits to visualize some of the phases detected by the XRD analysis. The TEM microscopy permits also to see the amorphous phases created by the grinding protocol which affects significantly the specific surface and the shrinking of the new materials. For each section, we made some conclusions with interpretation in order to integrate these results in civil engineering, classical/artisanal material construction and geotechnical fields.

关键词： Clay Structure PEG 6000/Clay Matrix Composite ICP Analysis Atterberg Limits Specific Surface Shrinking Microscopy Characterization

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LaF3-passivation of Porous Silicon for the Enhancement and Stabilization of Photoluminescence

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材料科学与工程（中英文版） 2010年第4期4卷 60-65页

作者： Sinthia Shabnam Mou Md. Atowar Rahman Mushtaq ahmed Sobhan Md. Abdur Rahman Abu Bakar Md.ismail Department of Applied Physics and Electronic Engineering Rajshahi University Rajshahi 6205 Bangladesh

Passivation of porous silicon (PS) with LaF3 has been investigated in this article. PS has been prepared by electrochemical etching single crystal Silicon (Si) in a solution of HF and ethanol at various current densities. Just after fabrication, PS samples were passivated with e-beam-evaporated LaF3 of various thicknesses. SEM, XRD and EDX confirmed a heteroepitaxy of LaF3, PS and Si. The photoluminescence (PL) peak appeared at 696 nm that confirmed the luminescence from the PS and not from LaF3. The LaF3 layer did not affect appreciably the size of silicon crystallites as the full width half maxima (FWHM) of the PL band remained nearly constant with LaF3 thickness. Thin layer of LaF3 produced a good enhancement of photoluminescence of PS where as thicker layer provided the luminescence stability. The PL intensity degraded due to aging, but it was possible to recover the degraded PL intensity by annealing the LaF3/PS/Si structure at 400 °C for 10 mins in air. Altogether, it can be concluded that annealed LaF3 on PS can provide the required passivation of PS that might enable it to be used in the photonic devices.

关键词：光致发光钝化处理氟化镧多孔硅光稳定发光强度结构退化电子束蒸发

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塔哈·侯赛因的《山鲁佐德之梦》与鲁迅的《补天》对比研究

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东方论坛（青岛大学学报） 2010年第5期 83-90页

作者：李哈布开罗大学文学院

塔哈·侯赛因的《山鲁佐德之梦》与鲁迅的《故事新编》均重视从多个层面对神话人物进行塑造,并在其中凝聚作者的哲学、政治、思想以及对社会的关注,使神话形象言其所不能。这两部作品在形式上存在诸多相似点,而在主题和内容方面却大相... 详细信息

塔哈·侯赛因的《山鲁佐德之梦》与鲁迅的《故事新编》均重视从多个层面对神话人物进行塑造,并在其中凝聚作者的哲学、政治、思想以及对社会的关注,使神话形象言其所不能。这两部作品在形式上存在诸多相似点,而在主题和内容方面却大相径庭。利用神话人物反映现实生活的手法,在鲁迅和塔哈·侯赛因的笔下得到完美的体现,这正是源于两位作家杰出的创造力和想象力。

关键词：鲁迅塔哈·侯赛因神话象征比较

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温室气体四氟化碳处理技术研究进展

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能源环境保护 2023年第2期37卷 73-84页

作者：朱烨林郑谐陈世杰刘菀凝艾曼沈锋华向开松刘恢中南大学冶金与环境学院湖南长沙410083 国家重金属污染防治工程技术研究中心湖南长沙410083

四氟化碳(CF_(4))是《京都协议书》规定与管控的典型非二氧化碳超强温室气体之一。随着铝电解、半导体等工业活动规模的不断扩大,CF_(4)排放量持续增加,加剧了全球气候变化,影响着人类赖以生存的环境质量,同时阻碍了相关产业的可持续发... 详细信息

四氟化碳(CF_(4))是《京都协议书》规定与管控的典型非二氧化碳超强温室气体之一。随着铝电解、半导体等工业活动规模的不断扩大,CF_(4)排放量持续增加,加剧了全球气候变化,影响着人类赖以生存的环境质量,同时阻碍了相关产业的可持续发展。随着碳达峰行动方案的落实,加大CF_(4)等非二氧化碳温室气体的控制力度已成为我国“碳达峰碳中和”战略目标达成的重要支撑。本文对CF_(4)的来源进行了系统地分析,阐述了CF_(4)主要行业来源、排放特征与生成机制。在综述了CF_(4)源头减排措施的基础上,分析了CF_(4)源头减排的局限性与末端处理的必然趋势。重点针对CF_(4)的末端处理,从物理和化学处理技术两大类方向总结了深冷分离、吸附法、膜分离、热力燃烧、热催化分解、等离子体高能分解、电催化分解等七种末端处理技术,阐述了相关方法的基本原理、应用案例和技术发展现状;根据各项技术的分解效率、温度、产物、能耗等参数,对比分析了技术间的优缺点;基于末端处理技术的行业需求和应用场景,研判了CF_(4)末端处理技术的未来挑战。

关键词：四氟化碳源头减排末端治理物理回收高效分解

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Current systematic reviews and meta-analyses of COVID-19

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World Journal of Virology 2021年第4期10卷 182-208页

作者： Mahmoud Nassar Nso Nso Mostafa Alfishawy Anastasia Novikov Salim Yaghi Luis Medina Bahtiyar Toz Sofia Lakhdar Zarwa Idrees Yungmin Kim Dawa Ongyal Gurung Raheel S Siddiqui David Zheng Mariam Agladze Vikram Sumbly Jasmine Sandhu Francisco Cuevas Castillo Nadya Chowdhury Ravali Kondaveeti Sakil Bhuiyan Laura Guzman Perez Riki Ranat Carlos Gonzalez Harangad Bhangoo John Williams Alaa Eldin Osman Joyce Kong Jonathan Ariyaratnam Mahmoud Mohamed ismail Omran Mariely Lopez Akwe Nyabera Ian Landry Saba Iqbal Anoosh Zafar Gondal Sameen Hassan ahmed Daoud Bahaaeldin Baraka Theo Trandafirescu Vincent Rizzo Department of Internal Medicine Icahn School of Medicine at Mount Sinai/NYC H&H QueensNew YorkNY 11432United States Department of Infectious Diseases Infectious Diseases Consultants and Academic Researchers of Egypt(IDCARE)Cairo 11221Outside of the USEgypt Department of Medicine Division of NephrologyUniversity of Tennessee Health Science CenterKnoxville CityTN 38103United States Department of Medical St.George's UniversityWest Indies 38901Grenada Department of Internal Medicine Faculty of MedicineCairo UniversityCairo 11221Egypt Department of Oncology Broomfiled HospitalMid and South Essex NHS Foundation TrustESSEXChelmsford 12422United Kingdom Department of Critical Care Unit Icahn School of Medicine at Mount Sinai/NYC H&H QueensNew YorkNY 11432United States

BACKGROUND Coronavirus disease 2019(COVID-19)has left a significant impact on the world's health,economic and political systems;as of November 20,2020,more than 57 million people have been infected worldwide,with over 1.3 million *** the global spotlight is currently focused on combating this pandemic through means ranging from finding a treatment among existing therapeutic agents to inventing a vaccine that can aid in halting the further loss of *** To collect all systematic reviews and meta-analyses published related to COVID-19 to better identify available evidence,highlight gaps in knowledge,and elucidate further meta-analyses and umbrella reviews that are yet to be *** We explored studies based on systematic reviews and meta-analyses with the keyterms,including severe acute respiratory syndrome(SARS),SARS virus,coronavirus disease,COVID-19,and SARS *** included studies were extracted from Embase,Medline,and Cochrane *** publication timeframe of included studies ranged between January 01,2020,to October 30,*** that were published in languages other than English were not considered for this systematic *** finalized full-text articles are freely accessible in the public *** Searching Embase,Medline,and Cochrane databases resulted in 1906,669,and 19 results,respectively,that comprised 2594 studies.515 duplicates were subsequently removed,leaving 2079 *** inclusion criteria were systematic reviews or meta-analyses.860 results were excluded for being a review article,scope review,rapid review,panel review,or guideline that produced a total of 1219 *** screening articles were categorized,the included articles were put into main groups of clinical presentation,epi-demiology,screening and diagnosis,severity assessment,special populations,and ***,there was a second subclassification into the following groups:gastrointestinal,cardiovascular,neurological,stro

关键词： Systematic review Meta-analyses COVID-19 Review Coronavirinae

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Modeling and Simulation of Recursive Least Square Adaptive （RLS） Algorithm for Noise Cancellation in Voice Communication

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通讯和计算机（中英文版） 2013年第11期10卷 1440-1444页

作者： Azeddine Wahbi Rachid Elgouri ahmed Roukhe Laamari Hlou Laboratory of Electrical Engineering and Energy System Faculty of Science Ibn Tofail University Kenitra 14000 Morocco Laboratory of Atomic Mechanical Photonics and Energy Faculty of Science Moulay Ismail University Meknes 50003 Morocco

In this paper a module consisting of a RLS (recursive least square) filter is modeled and verified to eliminate acoustic noise, which is a problem in voice communication. In this work the ANC (acoustic noise cancellation) is modeled using digital signal processing technique especially Simulink Blocksets. The needed algorithm code is generated in Matlab Simulink programming. At the simulation level, results of simulink implementation prove the module behavior for cancellation of noise in voice communication using the RLS adaptive algorithm. The main scope of this paper is to implement the module in real time onboard an autonomous DSK C6713 card in the future work, benefiting the low computational cost and the simplicity of the implementation using simulink programming.

关键词：自适应算法语音通信噪音消除 RLS 递推最小二乘建模 Simulink SIMULINK

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