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Article Tıpta Plazma Teknolojisi(İz Dergisi, 2015) Şaşmazel, Hilal; Sürücü, SedaPlazma sözcüğünü fizik dünyasına yazılı olarak sunan ilk kişi Langmuir’dir. Langmuir 1929 yılında gaz deşarj tüpleri üzerine yaptığı çalışmalarda plazmanın bir canlı gibi davrandığını düşünmüş ve iyonlaşmış gaz topluluğuna daha çok yakışacağını düşündüğü plazma adını vermiş. Plazma, içerisinde yüksüz türleri, negatif ve pozitif yüklü elektronları içeren iyonlaşmış gaz halidir. Evrenin % 99’u plazma durumunda, geriye kalan % 1’in bir bölümü katı, çok küçük bir bölümü de sıvı durumunda. Kuşkusuz, gaz durumundaki her ortamı plazma olarak tanımlayamayız. Ancak kozmik koşullar altında, soğuk yıldız atmosferleri plazma özelliği sergiler. Evrende hali hazırda var olan astro-plazmanın yanısıra, laboratuvarda oluşturulan plazma iki ana gruba ayrılabilir; yüksek sıcaklık veya füzyon plazma ve düşük sıcaklık veya gaz-yük boşalım plazması. Sıcak plazmaya örnek olarak güneş sistemi verilebilir. Soğuk plazma ise laboratuvar koşullarında elektriksel boşalım veya ışık kaynaklarıyla oluşturulabilir.Article PET ŞİŞELER NASIL ÜRETİLİR?(Bilim ve Teknoloji, 2015) Ergün, Gül CansuÖzellikle sıcak yaz günlerinde hemen her birimizin yanında mutlaka bir plastik su şişesi bulunur. Hatta gün içinde evde değilsek, iki belki üç şişe su değiştirdiğimiz oluyor. Akşam eve gittiğimizde ise buzdolabından mutlaka bir gazlı içecek çıkarıp, bardağımıza dolduruyoruz. Peki bu kadar çok tüketilen suyu ve içecekleri taşıyan plastik şişelerin nasıl üretildiğini biliyor musunuz?Article Unconventional Natural Gas From Abandoned Coal Mines: Modelling and Performance Prediction at the Frankenholz-St. Barbara Mining Complex(The International Journal of Mineral Resources Engineering, 2007) Durucan, Şevket; Shı, Ji-quan; Korre, AnnaThis paper describes a joint research project carried out by Imperial College and Deutsche Steinkohle Aktiengesellschaft (DSK), in which the Imperial College in house gas-water two-phase Coalbed Methane (CBM) simulator was further developed to model abandoned mine methane recovery in the Saar Coalfield. Historical data on mining and methane emissions, as well as the long-term methane production data monitored at the Hangard shaft was used to validate the model developed. A satisfactory match tothe historical and currrent field data was achieved. Predictionsfor future production opportunities were made for the Allenfeld shaft in conjunction with production from the Hangard shaft which has been in production since 1960.Article Bin Volume Selection in Relation To Hoist Output and Stream of Rock Extracted-Analysis of the System(The International Journal of Mineral Resources Engineering, 2008) Czaplıckı, Jacek M.This paper conducts an analytical description of the problem of shaft bin volume selection in relation to the hoist output given and to the stream of rock mass delivered to the shaft. Special attention is devoted to the stochastic nature of phenomena occurring during ine operation. The stream of mass transported is identified as the Gaussian and the hoist daily output as the random variable that can be described by a modified beta distribution. The bin volmu is considered as a function of either the average value by which the rock mass exceeds the hoisting capacity of transportation both per day or the average rock mass that is delivered to the shaft during the mean time of hoist repair plus the corresponding standard deviation of thise repair time. The rock mass fluctuation in the bin is also taken into account, and its effect included in the calculation procedure.Article İNSANOĞLUNUN PLASTİK İLE İMTİHANI(Bilim ve Teknoloji, 2015) Ergün, CansuStaudinger’in makromolekülleri keşfetmesi ile başlayan plastik çağı, 1930’lardan bugüne dünyamızı tamamen ele geçirmiş durumda. Günlük yaşamımıza, mesela sabah evden çıkana dek, şöyle bir göz atalım. Banyoda diş fırçası, havlu, saç kurutma makinesi, traş bıçağı, klozet kapağı, sabunluk-diş fırçalıklar. Mutfakta, ısıya dayanıklı plastik kaşıklar, fırın tutacakları, yapışmaz tavalar, su ısıtıcıları, tencere sapları, ocak düğmeleri, beyaz eşya kapakları, yiyecek ambalajları.. Salonda televizyon kumandası (ve hatta artık ekranları), koltuk süngerleri, sandalyeler, pencere pimapenleri. Evden çıkacakken giydiğimiz ayakkabılar, tokalar, kıyafetler, ceketler. Bunlar evde kullandığımız plastiklerin sadece bir bölümü.Article A Company-Perspective Cost Analysis of the Personal Dust Monitor (pdm)(The International Journal of Mineral Resources Engineering, 2007) Reed, W.r.; Volkweın, J.c.; Joy, G.j.The personal dust monitor (PDM) is a new coal mine respirable dust sampling instrument that has the ability to provide accurate end-of-shift and real-time respirable dust exposure data. A hypothetical cost comparison analysis of the PDM with the current MSHA-required coal mine dust personal sampling unit (CMDPSU) was conducted. Some simplifying assumptions were made to create hypothetical cases for analysis. This analysis was limited to respirable dust sampling of the one designated operator (DO) and one designated area (DA) for one mechanized mining unit (MMU) which operated one shift per day. Only sampling intervals of the minimum sampling as required by federal regulations and continuous sampling were analyzed. This cost analysis from the company perspective is only one part of an overall cost/benefit analysis that should be conducted at a later date. In this analysis, company-associated costs were examined for both sampling systems. Results show that the PDM, while it has high initial costs of approximately $ 12,600, may be a cost-effective sampling system for measuring coal mine respirable dust. The estimated present worth cost of conducting the minimum requried dust sampling over a five-year life ranges from $5,850 to $19,000 for the CMDPSU, with the higher present worth cost including costs of potential violations incurred. For the PDM, the comparable present worth cost is $14,900 to $19,300, with the lower present worth cost representing a lower capital cost of $8,150 per unit if more than 850 units are produced per year, while the higher present worth cost reflects the results with the higher $12,600 capital cost.Article Quality Cost Assessment in Mine Tunnelling With Drilling and Blasting(The International Journal of Mineral Resources Engineering, 2007) Kenzap, Serguei A.; Kazakıdıs, Vassilios N.A decision making process for equipment selection in mine lateral development is presented. This addressess the need of mine development projects to increase actual lateral development rates for single headings using drilling and blasting techniques. The approach described in this papaer focuses on quality issues in a lateral development cycle by linking them to the "time value of money" concept. Th total poor quality cost estimation in lateral development is presented in case study #1, where typical lateral development practice at Falconbridge Ltd (now Xstrata Nickel) in the Sudbury basin was analyzed. A conceptual example, presented in case study#2, showa the practical application of the proposed approach and emphasizes the benefits of discrete event simulation in conjunction with process quality quantification in mine lateral development.Article A CALCULATION METHOD FOR A SHOVEL-TRUCK SYSTEM WITH AN INCLINED HOIST OF TRUCKLIFT TYPE(The International Journal of Mineral Resources Engineering, 2008) Czaplıckı, Jacek M.The proposal to apply an inclined hoist of the Trucklift type in open pit mining hung in mid-air. Although this suggestion is quite interesting, no mine around the world was interested in such an installation. It appears that one of the main reasons for which the proposal missed its aim was the lack of the method of analysis and calculation of shovel-truck systems including such a type of hoist to allow an assessment of what kind of improvement might be expected if the hoist is employed in the system. This paper shows the method of analysis and calculation of shovel-truck systems with a hoist, considering the majority of the important compenents that have an influence on the course of the operation/exploitation process of the machinery system. An example is given to add to the communicativeness of the considerations and conclusions drawn.Article Flotation of Refractory Marmatite Ore by Using Ammoniacal Copper (ii) Solution as Activator(The International Journal of Mineral Resources Engineering, 2008) Rao, Feng; Song, Shaoxian; Tong, Xiong; Xıe, Xian; Lopez-valdıvıeso, AlejandroThe flotation of a refactory marmatite ore in China has been studied by using ammoniacal copper (II) solution as the activator in this work, in order to improve the Zn recovery of the marmetite flotation. The experimental results have shown that the ACS could increase the Zn recovery of 9%, compared withcopper sulphate (a commonly used activator for sphalerite and marmatite). The marmatite flotation with the ACS as activator consume much less lime because it was realized at pH 9, while that with copper sulphate as the activator is carried out around pH 12. The less lime consumption not only leads to savings on operation costs, but also reduces the corrosions of flotation celss and stirring tanks, etc. The mechanism by which the ACS acts as activator in marmatite flotation has been found to be attributed to the chemical adsorption of copper (II)-ammonia complexes (CuNH32 and Cu(NH3)22) on marmatite surfaces, leaving to active sites on the surfaces for the adsorption of xanthate ions.Article PLASTİKLERİN ŞEKİLLENDİRİLMESİ: DÖNEL KALIPLAMA(Bilim ve Teknoloji, 2015) Ergün, Gül CansuPlastik hammaddeler pellet veya toz halde elde edildikten sonra, markette karşımıza şekillendirilmiş, renklendirilmiş ve kullanıma hazır eşyalar olarak çıkarlar. Dünya çapında en fazla tüketilen plastikler, polietilen ve polistiren polimerleridir. Özellikle düşük ve yüksek yoğunluklu polietilen seçenekleri, polietilenin günlük hayatta kullanımına yönelik yaygın imkanlar sunar. Polistirenin ise köpük haliyle elde edilebilmesi, bu polimeri paketleme endüstrisinde rakipsiz kılmıştır.
