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Analysis of relations and forces of production in extraction And pearl industry in the Arabian Gulf 1900-1950 *
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بسبب محدودية الموارد الطبيعية، فأن سكان الخليج ومنذ القدم وجهوا جلّ نشاطاتهم توجهاً بحرياً: صيد الاسماك وصناعة اللؤلؤ العنصر الرئيس في حجم التشغيل، وتكوين الفائض الاقتصادي في المنطقة آنذاك.

لقد تزايدت أهمية هذا النشاط بخاصة بعد النصف الثاني من القرن التاسع عشر، لرواج تجارة اللؤلؤ عالمياً، وأنفتاح الخليج على الدول الاوروبية التي شهدت نهضة صناعية متسارعة، وحيث وصلت الخليج العديد من بضائعها ذات الاسعار المناسبة والنوعية الافضل.

إن عدد العاملين في صناعتهِ لم يقل عن 20-25% من مجموع العاملين في المنطقة خلال الربع الاول من القرن العشرين ويبين لنا المؤرخ J.G.Lorimer إن عدد العاملين وصل الى حوالي 90 ألف شخص من سكان قدر مجموعه بـ 300 ألف نسمة وذلك في أواسط العقد الأول من القرن العشرين. وبالأضافة الى العمل المحلي هناك وافدون من أيران والهند وباكستان مع وافدين من شرق أفريقيا، أستُقدم العديد منهم كعبيد سخرهم مالكوهم للعمل في صناعة اللؤلؤ وذلك بالرغم من محاربة السلطات البريطانية آنذاك لأعمال القرصنة وتجارة العبيد في منطقة الخليج والمحيط الهندي.

تفصح التراتيب الوظيفية في صناعة اللؤلؤ عن وجود تسع فئات مُقسمة بدقة حسب نوع العمل الذي تقوم به كل فئة. والعنصران الفاعلان في العملية الانتاجية هما:-

التاجر "الممول": يُمول العاملين بسلف تصل فائدتها الى حوالي 25% على أساس الموسم الذي يستمر بين 4-5 أشهر. وغالباً ما يستحوذ على الجزء الاعظم من الارباح بطريقة أو بأخرى..

الغواص ومساعده: يُلاحظ هنا تناقضٌ واضح، فمن ناحية هما الحلقة الاهم والاخطر في العملية الانتاجية وحيث لا يملك الغواص الا قابلياته البدنية أثناء عملية الغوص؛ ومن ناحية أخرى هما من أكثر المتضررين مادياً وأجتماعياً وصحياً بين الاطراف الاجتماعية المشاركة في هذه الصناعة.

لم تعرف هذه المهنة نظاماً للأجور، بل كانت تعمل وفق طريقة "المحاصصة" ونادراً ما كان يحصل الغواصون ومساعدوهم على ما يسدون به سلفهم وديونهم السابقة مع فوائدها المتزايدة.

    النقطة المركزية: ان العاملين عادةً ما يبقون في دين مستديم، وهذا ما يخوّل الممول حسب العرف السائد آنذاك والذي هو بمثابة قانون مُلزم من الابقاء عليهم للعمل في المواسم اللاحقة.

    لقد تراجعت صناعة اللؤلؤ منذ أوائل ثلاثينيات القرن الماضي، أثر اجتياح اللؤلؤ" الرخيص" المستزرع في اليابان ومناطق أخرى من العالم. ومن حسن حظ المنطقة ان صادف ذلك البدايات الاولى للأكتشافات النفطية حيث انتقل العديد من العاملين فيها الى الصناعة النفطية الحديثة.

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Publication Date
Wed Jul 05 2023
Journal Name
Chalcogenide Letters
Optimization physical properties of CdTe /Si solar cell devices fabricated by vacuum evaporation
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We investigated at the optical properties, structural makeup, and morphology of thin films of cadmium telluride (CdTe) with a thickness of 150 nm produced by thermal evaporation over glass. The X-ray diffraction study showed that the films had a crystalline composition, a cubic structure, and a preference for grain formation along the (111) crystallographic direction. The outcomes of the inquiry were used to determine these traits. With the use of thin films of CdTe that were doped with Ag at a concentration of 0.5%, the crystallization orientations of pure CdTe (23.58, 39.02, and 46.22) and CdTe:Ag were both determined by X-ray diffraction. orientations (23.72, 39.21, 46.40) For samples that were pure and those that were doped with

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Publication Date
Tue Dec 01 2015
Journal Name
Journal Of Engineering
Ten Years of OpenStreetMap Project: Have We Addressed Data Quality Appropriately? – Review Paper
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It has increasingly been recognised that the future developments in geospatial data handling will centre on geospatial data on the web: Volunteered Geographic Information (VGI). The evaluation of VGI data quality, including positional and shape similarity, has become a recurrent subject in the scientific literature in the last ten years. The OpenStreetMap (OSM) project is the most popular one of the leading platforms of VGI datasets. It is an online geospatial database to produce and supply free editable geospatial datasets for a worldwide. The goal of this paper is to present a comprehensive overview of the quality assurance of OSM data. In addition, the credibility of open source geospatial data is discussed, highlight

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Publication Date
Tue Sep 01 2020
Journal Name
Journal Of Engineering
Buckling Behavior of Aluminum Alloy Thin-Walled Beam with Holes under Compression Loading
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Thin-walled members are increasingly used in structural applications, especially in light structures like in constructions and aircraft structures because of their high strength-to-weight ratio. Perforations are often made on these structures for reducing weight and to facilitate the services and maintenance works like in aircraft wing ribs. This type of structures suffers from buckling phenomena due to its dimensions, and this suffering increases with the presence of holes in it. This study investigated experimentally and numerically the buckling behavior of aluminum alloy 6061-O thin-walled lipped channel beam with specific holes subjected to compression load. A nonlinear finite elements analysis was used to obtain the

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Publication Date
Wed Sep 01 2021
Journal Name
Journal Of Engineering
Thermal Buckling of Laminated Composite Plates Using a Simple Four Variable Plate Theory
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In this study, the thermal buckling behavior of composite laminate plates cross-ply and angle-ply all edged simply supported subjected to a uniform temperature field is investigated, using a simple trigonometric shear deformation theory. Four unknown variables are involved in the theory, and satisfied the zero traction boundary condition on the surface without using shear correction factors, Hamilton's principle is used to derive equations of  motion depending on a Simple Four Variable Plate Theory for cross-ply and angle-ply, and then solved through Navier's double trigonometric sequence, to obtain critical buckling temperature for laminated composite plates. Effect of changing some design parameters such as, ortho

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Publication Date
Tue Jan 01 2019
Journal Name
Optical And Quantum Electronics
Photocatalytic activity of anatase titanium dioxide nanostructures prepared by reactive magnetron sputtering technique
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Publication Date
Fri Jul 19 2019
Journal Name
Communications Chemistry
Positive functional synergy of structurally integrated artificial protein dimers assembled by Click chemistry
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Abstract<p>Construction of artificial higher order protein complexes allows sampling of structural architectures and functional features not accessible by classical monomeric proteins. Here, we combine in silico modelling with expanded genetic code facilitated strain promoted azide-alkyne cycloaddition to construct artificial complexes that are structurally integrated protein dimers and demonstrate functional synergy. Using fluorescent proteins sfGFP and Venus as models, homodimers and heterodimers are constructed that switched ON once assembled and display enhanced spectral properties. Symmetrical crosslinks are found to be important for functional enhancement. The determined molecular structure of one artific</p> ... Show More
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Publication Date
Thu Feb 01 2024
Journal Name
Heliyon
Removal of amoxicillin from contaminated water using modified bentonite as a reactive material
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This study concerns the removal of a trihydrate antibiotic (Amoxicillin) from synthetically contaminated water by adsorption on modified bentonite. The bentonite was modified using hexadecyl trimethyl ammonium bromide (HTAB), which turned it from a hydrophilic to a hydrophobic material. The effects of different parameters were studied in batch experiments. These parameters were contact time, solution pH, agitation speed, initial concentration (C0) of the contaminant, and adsorbent dosage. Maximum removal of amoxicillin (93 %) was achieved at contact time = 240 min, pH = 10, agitation speed = 200 rpm, initial concentration = 30 ppm, and adsorbent dosage = 3 g bentonite per 1L of pollutant solution. The characterization of the adsorbent, modi

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Publication Date
Wed Jul 06 2022
Journal Name
International Journal Of Biomaterials
Extracellular Enzyme of Endophytic Fungi Isolated from Ziziphus spina Leaves as Medicinal Plant
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Endophytic fungi live inside plants or any part of them without creating any visible pathogenic signs. Endophytic fungi are found within medicinal plants and have shown strong biologic activity, such as anticancer and antioxidant activities, as well as producing extracellular enzymes. In this study, different fungal strains were isolated from the leaves of the medicinal plant Ziziphus spina, including Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Cladosporium sp., Rhizopus sp., and Mucor sp. Extracellular enzymes have been quantified using agar plate-based methods in which fungi were grown in specified growth media to detect the enzymes produced. The results showed that A. niger has the highest ability to produce amy

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Publication Date
Tue Feb 01 2022
Journal Name
Civil Engineering Journal
Calibration of a New Concrete Damage Plasticity Theoretical Model Based on Experimental Parameters
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The introduction of concrete damage plasticity material models has significantly improved the accuracy with which the concrete structural elements can be predicted in terms of their structural response. Research into this method's accuracy in analyzing complex concrete forms has been limited. A damage model combined with a plasticity model, based on continuum damage mechanics, is recommended for effectively predicting and simulating concrete behaviour. The damage parameters, such as compressive and tensile damages, can be defined to simulate concrete behavior in a damaged-plasticity model accurately. This research aims to propose an analytical model for assessing concrete compressive damage based on stiffness deterioration. The prop

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Publication Date
Wed Jan 01 2020
Journal Name
International Conference Of Numerical Analysis And Applied Mathematics Icnaam 2019
Synthesis of nanostructure diamond-like carbon thin films by atmospheric pressure plasma jet
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In this work, diamond-like carbon (DLC) thin films were prepared from Cyclohexane. Thin films were deposited on quartz substrate by atmospheric pressure Argon plasma jet system. The plasma jet system was applying high voltage sinusoidal waves of frequency 28 kHz and potential difference of 7.5kV peak to peak across the electrodes. The effect of annealing at 400, 500 and 600 °C under vacuum for two hours on optical properties and structural properties of the DLC thin films were investigated. This effect was clarified by X-ray diffraction (XRD), FTIR, UV-Visible absorption, Scanning Electron Microscopy (SEM) and Raman Spectroscopy. The X-ray diffraction patterns for the annealing DLC thin films show two broad peaks at 2θ, 26.62° and 51.58

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