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The goals of the present work are: (1) A theoretical analysis of possible reaction pathways to the synthesis of methanol and methane from CO2 and H2O and the selection of the best path from the view point of energy. (2) Investigation of the kinetic of assumed reactions. For determination of mechanism, BOC-MP method is used. By using of this theory, it is possible to calculate the thermodynamic and kinetic parameters and therefore predict the intermediates and the mechanism of heterogeneous catalytic reaction. With...

Edirne, which is one of the bigest city in western Turkey (Figure 1), has been damaged by floods and flashfloods with an increasing frequency and intensity over the years. This study was prepared as a preliminary investigation and aimed to research the floods and flooding in Edirne city (Turkey). For creating the topographic database in Geographic Information System (GIS), 1/25000 and 1/250000 scale topographic maps and satellite images was used. Subbasins areas of Meric River and flood area in Edirne city center ...

The general properties and distribution of low rank coal occurrences were investigated in Biga Peninsula, Turkey. Coal occurrences were alternated along with Tertiary clastic, volcanoclastic and continental units in the peninsula, one of the basic metallic and industrial mineral potential regions in Turkey. The collected twenty-six lignite samples from different beds were analyzed and evaluated. Proximate analyses contain to measure of moisture, ash, volatile matter, and fixed carbon parameters. The parameters of ...

In this study, enhancement and stabilization of photoluminescence (PL) by porous silicon (PS) were investigated. The PS samples were metallized in solutions containing 3 mM NaNO3 metal salt using immersing plating method. The surface bond configuration of PS was monitored by Fourier Transmission Infrared Spectroscopy (FTIR) and it was found that the PS surface was oxidized after the metallization. The PL intensity increased after certain critical immersion times and PL spectrum shifted towards the high energy regi...

All European papers consider the efficiency and quality of education as a fundamental premise of social cohesion, economic growth and sustainable development in the transition towards a knowledge society. The major reform processes initiated by the government in higher education, decentralization and quality management, are fully compatible and convergent with the European direction of reform in order to achieve the fundamental objectives of the ’Lisbon Process’. Debt of any institution of the national education s...

Floods are river basin wide phenomena and they often create common problems with locally varying intensity. The flood disaster management is highly dependent on early information and needs forecasts and data from the river basin as a whole. The starting point for flood risk management planning is the assessment of flood risks, based on the information about the river basin and floods in the past. The next step is developing strategies for reaction when flooding events are prognosticated, and evaluation of these st...

In order to prepare minimal feature vectors to be used in a Content Based Image Recognition (CBIR) system, we are proposing methods that can accurately identify the main colors contained in a digital image. The methods use the “LAB” color space properties that allow for all the colors of the same intensity or luminance “L” to be placed uniformly in the same “ab” plane. Basically, RGB images are first preprocessed: trimmed, scaled and transformed in the LAB color space. Then (a,b) pairs, corresponding to large pixe...

The study has been aimed at development of cheap sorbents of toxic heavy metals and radionuclides based on low rank, low energetic coals in combination with chitosan for use in treatment of both waste and drinking water and construction of active geochemical barriers. Sorbents based on lignite and naturally oxidized lignite (oxihumolite, leonardite) were prepared, both raw and impregnated with chitosan from its solution in oxalic acid. The sorbents were characterized by chemical and structural analyses. Their sorp...

Glauberite mineralization from Cayirhan, Ankara (Central Anatolia) has been investigated and identified the major mineralogical, petrographical and geochemical properties. Glauberite occurrence, a sodium calcium sulfate mineral (Na2Ca(SO4)2) by evaporation, is underneath the gypsum mineralization which accumulated at the contact zone between Pliocene aged Ucyatak and Softa formations. The mineralization is related to clay and mudstone, and accompanies with thenardite, gypsum, anhydrite, mirabilite and blodite. Maj...

In this paper, we have discussed a third-degree non-polynomial spline solution for the numerical solution to nonlinear boundary value problems (BVPs) and compare other metods. Two numerical examples are given to illustrate the efficiency and performance of the method. The method gives accurate results in both the linear and nonlinear cases.

Coal is one of the main energy sources in Turkey; it is used for both domestic heating and energy generation in power plants. However, most of these coals have low calorific value, high ash and sulfur content and high slagging potential. Therefore, they usually need to be cleaned before using in heating or power generation. Coal preparation operations consider the removal of ash forming material from the Run-of-Mine (ROM) coal. Dense-medium separators are employed in the majority of coal preparation plants for thi...

Due to its intensive data processing and highly distributed organization, the multidisciplinary Earth Science applications community is uniquely positioned for the uptake and exploitation of Grid technologies. Information and Communication Technologies have proven to be key instruments in activities targeted at protecting the environment and its integration in sustainable development policies. Grid computing capabilities are powerful tools to manage large volumes of Earth observation data and provide the Earth Sci...

Foundries produce metal castings from ferrous or non-ferrous alloys and they operate in various locations around the world. A typical foundry workplace is composed of furnace area, pouring area, core making area, shaking out area and fettling area. The manufacturing process involves the melting of metal into a liquid, the pouring of molten metal into a cast, the removing of casting and the cleaning / finishing of the cast piece. Dusts arise almost in every of these steps of foundry processes. Solid waste streams f...

Slag from pig iron, steel and cast iron production belong to metallurgical slag. A blast furnace slag is from pig iron production, slag from electric arc furnace and electric induction furnace are from steel production and stag from cupola furnace proceeds from cast iron production. There are given basic information about chemical composition and physical properties of slag in this contribution (melting temperature). As another properties basicity, content of free lime and structure of slag will be determined. Che...

Castings production cover different technologies of mouls and cores production, different technologies of metal melting (depended on casting material) and technologies of pouring. All these technologies have got some advantages, disadvantages and generate some kinds of by products.There are described in the contribution the basic technologies of moulds production (sand casting, shell moulding, investment casting, lost foam casting, shaw process, vacuum process), pouring technologies (gravity casting, die casting,s...

Abrasive waterjet technology (AWJ) is one of the fastest growing machining processes. It is environmentally friendly, can machine almost any engineering materials. It has received considerable attention from various industries due to its beneficial characteristics. Compared with traditional and most non traditional machining technologies, AWJ exhibits a high potential in the field of the shape machining of hard or brittle materials such as ceramics, glass and rocks. The present study investigates the machinability...

The paper presents the results of precise monitoring of the regime of groundwater at the territory of the Geophysical Observatory of IDG RAS "Mikhnevo". Variations of water level in the isolated aquifer depend on regime controlling factors that have episodic and stationary effects on the aquifer. Detecting and studying the reaction of groundwater to stationary lunisolar tides are of special interest. The tidal effect in variations of groundwater level can be considered as a probing signal for diagnostics of stress...

We propose a device which produces a high density cloud of spray that is consisted mostly of water micro droplets. The cloud automatically occurs when an electromagnetic pulse or/and shock wave from a close explosion matches the device. The ratio of absorbed energy of the dangerous shock wave depends on the density of the cloud and on its spreading speed as well as on the size and the mass of micro droplets. We have developed a mathematical model of physical processes in the Absorber. Numerical simulations show sa...

The article briefly characterizes a web service for thermochemical calculations in term of its implementation and provided methods. It specifies web service error conditions and their dependency on input parameters as well. The article closely deals with a two approaches aimed at solution of error conditions. The first approach is based on exception utilization. It defines fault in WSDL file, describes fault structure in XML schema, creation of exception on the web service side and exception processing on the clie...