105 research outputs found
Kolaborasi Hulagu Khan dan Nasiruddin At-Tusi terhadap Pengembangan Dunia Islam Pasca Runtuhnya Dinasti Abbasiyah
No full textSkripsi ini berjudul Kolaborasi Hulagu Khan dan Nasiruddin At-Tusi Terhadap Pengembangan Dunia Islam Pasca Runtuhnya Dinasti Abbasiyah. Skripsi ini bertujuan untuk mengetahui bagaimana kolaborasi Hulagu Khan dan Nasiruddin At-Tusi terhadap pengembangan dunia Islam pasca penaklukan Baghdad yang meliputi tokoh-tokoh yang berperan dalam hal tersebut. Penelitian ini menggunakan metode Sejarah dan menggunakan penelitian kepustakaan (Library Research). Adapun urutan penelitian ini adalah Heuristik, kritik sumber, Interpretasi dan Historiografi. Selanjutnya, hasil penelitian ini adalah mengemukanya dua tokoh utama dalam pengembangan dunia Islam pasca takluknya kota Baghdad yaitu Hulagu Khan seorang panglima perang pasukan Mongol dan Nasiruddin At-Tusi seorang ilmuwan multi-talenta. Kedua tokoh ini bertemu pada saat penaklukan benteng Alamut oleh bangsa Mongol. Nasiruddin At-Tusi merupakan tahanan di benteng tersebut akhirnya di bebaskan. Hulagu Khan melihat dalam diri At-Tusi memiliki kecerdasan dan pandai bertutur kata di atas rata-rata orang awam, selanjutnya mengangkat At-Tusi menjadi penasehat pribadinya. Kolaborasi antara Hulagu Khan dan Nasiruddin At-Tusi pada akhirnya membuat dunia Islam mampu berkembang kembali
Weak Compactness in the Space of Operator Valued Measures and Optimal Control
No full textPart 2: Control of Distributed Parameter SystemsInternational audienceIn this paper we present a brief review of some important results on weak compactness in the space of vector valued measures. We also review some recent results of the author on weak compactness of any set of operator valued measures. These results are then applied to optimal structural feedback control for deterministic systems on infinite dimensional spaces
Chemical composition of wet precipitation of air pollutants: A case study in Karachi, Pakistan
No full textAbstractAir pollution has been considered one of the most important environmental challenges because of its direct effect on ecosystems and human health. Temporal changes in the composition of 20 samples of rainwater in the arid region of Karachi, Pakistan during the southwest monsoon of 2009 have been monitored to carry out the indirect assessment of air quality. The study has been fulfilled with the aim of identifying the level of air pollution, and the relative contribution of possible anthropogenic activities. Metal ions were analyzed to predict health risks. Rain samples were found to be alkaline (pH 5.55-7.55) due to the influence of calcium and magnesium rich particles. Continuous rains in consecutive days showed a remarkable decline in air pollution while the dry season boosted up the level of pollution. Strong correlations of total dissolved solids with K+, Na+, Ca2+, Mg2+, and Cl− were observed. A relatively weak correlation of total suspended particles with metals showed the possibility of some other particulate matters being suspended in the air. Principal component analysis and analysis of means were used to predict the anthropogenic source of pollution. This study will be helpful to formulate strategic planning and policies for controlling the level of air pollution in the city
DETERMINATION OF POINTS OF ZERO CHARGE OF NATURAL AND TREATED ADSORBENTS
No full textAlthough particle size and its measurement are intuitively familiar to particle technologists, the concept of point of zero charge (pzc) is less widely understood and applied. This is unfortunate since it is at least as fundamentally important as particle size in determining the behavior of particulate materials, especially those with sizes in the colloidal range below a micrometer. pzc is related to the charge on the surface of the particle and strongly depends on the pH of the material; so it influences a wide range of properties of colloidal materials, such as their stability, interaction with electrolytes, suspension rheology, and ion exchange capacity.The pH dependence of surface charges was quantified for four different adsorbent–aqueous solution interfaces. The points of zero charge were determined for activated charcoal, granite sand, lakhra coal, and ground corn cob materials using three methods: (1) the pH drift method, measuring pH where the adsorbent behaves as a neutral specie; (2) potentiometric titration, measuring the adsorption of H+ and OH- on surfaces in solutions of varying ionic strengths; (3) direct assessment of the surface charge via nonspecific ion adsorption as a function of pH. The intrinsic acidity constants for acid and base equilibria, \mbox{p}K_{\rm a1}^{\rm s} and \mbox{p}K_{\rm a2}^{\rm s}, were also calculated. Lakhra coal was found to have the lowest pzc value among all other adsorbents studied owing to the presence of a large amount of humus material. The results were used to explain general connections among points of zero charges, cation exchange capacity, and base saturation % of adsorbents.Points of zero charge, adsorbent, cationic exchange capacity, surface charge density, solid–liquid interface
Rheological characterization of vegetable oil blends: Effect of shear rate, temperature, and short‐term heating
No full textCHEMICAL COMPOSITION OF WET PRECIPITATION OF AIR POLLUTANTS: A CASE STUDY IN KARACHI, PAKISTAN
No full textAir pollution has been considered one of the most important environmental challenges because of its direct effect on ecosystems and human health. Temporal changes in the composition of 20 samples of rainwater in the arid region of Karachi, Pakistan during the southwest monsoon of 2009 have been monitored to carry out the indirect assessment of air quality. The study has been fulfilled with the aim of identifying the level of air pollution, and the relative contribution of possible anthropogenic activities. Metal ions were analyzed to predict health risks. Rain samples were found to be alkaline (pH 5.55-7.55) due to the influence of calcium and magnesium rich particles. Continuous rains in consecutive days showed a remarkable decline in air pollution while the dry season boosted up the level of pollution. Strong correlations of total dissolved solids with K+, Na+, Ca2+, Mg2+, and Cl-were observed. A relatively weak correlation of total suspended particles with metals showed the possibility of some other particulate matters being suspended in the air. Principal component analysis and analysis of means were used to predict the anthropogenic source of pollution. This study will be helpful to formulate strategic planning and policies for controlling the level of air pollution in the city.La contaminación atmosférica se ha considerado como uno de los desafíos ambientales más importantes a causa de su impacto directo en los ecosistemas y la salud humana. Se monitorearon los cambios temporales en la composición de 20 muestras de agua de lluvia en la región árida de Karachi, Pakistán, durante el monzón del suroeste de 2009, para evaluar de forma indirecta la calidad del aire. El objetivo del estudio fue identificar los niveles de la contaminación atmosférica y su posible componente antropogénico. Se analizaron los iones de metales con el fin de predecir riesgos para la salud. Se encontró que las muestras de lluvia fueron alcalinas (pH 5.55-7.55) debido a la presencia de partículas ricas en calcio y magnesio. Las lluvias continuas en días consecutivos mostraron un descenso notable en los niveles de contaminación, en tanto que la estación seca los potenció. Se observaron correlaciones importantes del total de sólidos disueltos con K+, Na+, Ca2+, Mg2+ y Cl-, así como una correlación relativamente débil del total de partículas suspendidas con los metales, lo que sugiere la presencia de otras partículas suspendidas en el aire. Se utilizaron análisis de componentes principales y de medias para predecir fuentes antropogénicas de contaminación. Este estudio será útil para definir la planeación estratégica y formular políticas orientadas a controlar los nivel de contaminación atmosférica en la ciudad
KINETIC STUDY OF THE OXIDATWE DECOLORIZATION OF XYLENOL ORANGE BY HYDROGEN PEROXIDE IN MICELLAR MEDIUM
No full textThe Power Generation from Coal in Pakistan: Assessment of Physicochemical Pollutant Indicators in Indigenous Reserves in Comparison to the Foreign Coal
No full textElectricity production through coal combustion is the only viable solution in minimum timing. As environmental chemists, our primary goal is to assess environmental hazards and suggest cost-effective technologies for reducing combustion pollutants. In the present study, indigenous coal samples from different mines were analyzed for their physicochemical properties and toxic metals. Five samples from foreign coal mines were also studied for comparison purposes and already in use for power generation. The sulfur content in Thar coal (0.62 %) is similar to foreign samples of Indonesian and Mozambique samples (0.35 – 1.63 %). Heating values of local coals show their potential as future fuel. The principal component analysis was applied to the data. It interprets that the concentration of toxic metals in indigenous and foreign samples is lower than the reported Greece samples. The concentration of metals in Badin coal samples is similar to foreign studied samples and is lower than the reported China, South Africa and other local samples. Copper (77.64 mg/kg), Zinc (63.23 mg/kg), Chromium (75.80 mg/kg), Mercury (0.22 mg/kg) and Manganese (119.07 mg/kg) are found to be high in Thar and Lead (49.41 mg/kg) in Lakhra. Balochistan is elevated in the concentration of nickel (52.63 mg/kg). It becomes obligatory for the policy makers of the country to suggest legislation for the use of appropriate Clean Coal Technologies (CCT) in the use of the coal in power sector
Manajemen Sarana Prasarana Dalam Meningkatkan Kualitas Lembaga Pendidikan
No full textManagement of educational facilities and infrastructure is a process of cooperation in utilizing all educational infrastructure facilities effectively and efficiently. And this shows that the facilities and infrastructure in schools need to be utilized and managed properly for the benefit of the learning process in educational institutions. Therefore, infrastructure management is very important because without good infrastructure management, an educational institution will not run effectively and efficiently. The problems that will be studied in this study are examining the definition of infrastructure management, the principles of infrastructure management, and the infrastructure management process. The purpose of writing this article is to describe and analyze infrastructure management in improving the quality of educational institutions. The method used in this research is qualitative research with a literature study approach. In the literature study, the author conducts literature collection activities related to infrastructure management in improving the quality of educational institutions. The final result of this study aims to find out the definition of infrastructure management, the principles of infrastructure management, and the infrastructure management process
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