Purchasing power parity: An Application for Turkey (1980-1987)

Ankara : The Department of Management and the Institute of Management Sciences of Bilkent University, 1989.Thesis (Master's) -- Bilkent University, 1989.Includes bibliographical references leaves 39-42Purchasing Power Parity (PPP) is claimed to be the oldest and simplest theory in determining the exchange rates of currencies. With its three versions, absolute PPP, relative PPP, and efficient markets PPP, this theory argues that price index levels of the countries are considered while setting the exchange rates. In this study, a general review of the theorj' and its failures are initially summarized. As the main purpose of the paper, the relative PPP has been applied for Turkey between 1980 and 1987 by taking USA as the comparision country. The application has been concentrated on both the official and black-market exchange rate determinations.Bilge, CemM.S

The effect of green biobased binder on structural, mechanical, liquid absorption and wetting properties of coated papers

Synthetic styrene-butadiene (SB) and styrene-acrylic (SA) latex binders used in paper coating formulations are common and based on unsustainable petroleum sources. Today\u27s papermaking industry turns towards sustainable substitutes that do not compromise quality, and reduce carbon emission, toxic substance release and waste disposal concerns related to fossil fuel sources. In this study, colloidal starch-based latex nanoparticles that do not require cooking were used for pigment coating and coated on the paper surfaces. The effects of these new biobased binders on the structural and mechanical strength properties, liquid absorption, wetting and surface topography of the paper were investigated and compared with the properties of coated paper that SB latex was used as a coating binder. The results demonstrated that the biobased latex decreases the grammage of paper while maintaining an identical thickness relative to the SB latex samples. The porosity, permeability and roughness of biobased latex are found higher than the SB latex. The biobased latex successfully replaced SB latex at 1:1 ratio and enabled an equivalent of bursting, tear, tensile strength and structural properties

Pollution profile and waste minimization study for a corn processing industry

Bu çalışmada Marmara Bölgesi’nde faaliyet gösteren büyük bir mısır işleme endüstrisi için kirlenme profili oluşturularak, çeşitli atık azaltım önerileri getirilmiştir. Bu amaçla söz konusu tesiste oluşan atıksu kaynak ve miktarları ile atıksu dışındaki atıkların tür, miktar ve özellikleri incelenmiştir. Tesiste üretim sürekli olup, ıslak öğütme ve rafineri olmak üzere iki temel proses mevcuttur. Tesisin üretim kademesindeki her bir işlem esnasında oluşan kirlilik konsantrasyonu belirlenerek kirlilik profili oluşturulmuştur. Endüstrinin biyolojik ve kimyasal kısımdan oluşan üç kademeli ileri atıksu arıtma tesisinin verimi ile deşarj suyunun kalitesi incelenerek ulusal ve uluslararası deşarj standartlarıyla kıyaslanmıştır. Kirlenme profilinin oluşturulmasında 2004-2005 dönemine ait bir yıllık kompozit numune bazlı analiz sonuçları dikkate alınmıştır. Kirlenme profili için KOİ yükü, deşarj suyunun değerlendirilmesinde ise KOİ, amonyak, nitrat, toplam fosfor ve askıda katı madde parametreleri incelenmiştir. Tesis için oluşturulan kirlenme profili incelendiğinde birim ürün başına oluşan atıksu miktarının rafineri prosesinde literatürle uyumlu olduğu; ıslak öğütme prosesinde ise literatür değerinin üstünde olduğu görülmüştür. Birim ürün başına KOİ yükleri incelendiğinde ise tesis değerlerinin literatür değerinin altında kaldığı görülmüştür. Atıksu oluşumu ve kirlilik açısından en önemli payı ıslak öğütme prosesinde yer alan evaporatör kondanse suyu oluşturmaktadır. İşletmenin arıtma tesisi performansına bakıldığında ise çıkış suyu değerlerinin ilgili ulusal ve uluslar arası yönetmelik limitlerini rahatlıkla sağladığı görülmektedir. Anahtar Kelimeler: Atık azaltımı, ileri atıksu arıtımı, kirlenme profili, mısır işleme endüstrisi.Products such as starch, gluten, glucose, dextrin, fructose etc. can be obtained from corn processing. Corn based glucose products are key ingredients in the growing international markets. As the intermediate products, the vegetable oil is bought by catering factories, protein and whole-wheat are bought by the farmers for animal feed, and fructose obtained from the starch is bought by food processing industries for sweetening and beverage. Effluent from corn milling industry is known as high strength wastewater due to its high protein and starch content. Wastewater from corn wet mill industries has high COD?s (chemical oxygen demand) mainly of soluble and biodegradable character, with an initial inert COD content of less than 15%. This character has promoted the application of biological processes as appropriate treatment technology. Anaerobic and/or aerobic biological treatment systems have been used to treat these types of effluents. In this paper, a pollution profile study for a corn processing industry located in Marmara Region as 21 ha was performed and some waste minimization approaches were proposed. For this purpose, the sources and the quantities of wastewater and other types of wastes generated in the industry were investigated. Around 264000 tons of corn are processed and 997000 tons of water are used annually in the investigated industry. The mean specific water usage can be calculated as  about 3.8 m3/t-corn including regeneration and washing waters. The studied industry has a three-stage advanced wastewater treatment plant (WWTP) including anaerobic expanded granular sludge bed reactor (EGSB), intermittently aerated single sludge activated sludge system for biological nitrogen (N) removal and chemical post treatment unit for phosphorus (P) removal. Simultaneous C and N removal is achieved by the aerobic treatment stage. Chemical P removal has been performed by using FeCl3 as the coagulant in the third stage. The final effluents from the WWTP are discharging to a nearby creek. The related corn processing plant has two main production steps including wet mill and starch slurry production. In the wet mill process, corn germ, fiber, gluten and starch slurry are produced from corn by steeping. The starch slurry is further processed to produce glucose, fructose and dextrin in the starch slurry derivatives units. Efficiency of the existing three stage advanced wastewater treatment plant and the quality of effluents from the WWTP were investigated and compared with national and international discharge standards. One year data set (2004-2005) was considered to generate the pollution profile. All analytical measurements have been carried out by APHA standard methods at the wastewater laboratory of the industry. Control analyses have also been performed by Environmental Engineering Department of Istanbul Technical University on monthly basis. COD parameter for the pollution profile and parameters including COD, ammonium, nitrate, total phosphorus, suspended solids and pH were considered for the evaluation of effluents from the WWTP. The identified three wastewater sources from the wet mill process and seven wastewater sources from refinery process were characterized and the pollution profile was generated. The pollution profile have shown that the amount of wastewater generated per ton of raw material in the refinery process is consistent with the related literature, however in wet milling process the corresponding value is above the literature figure. The COD loading values are also in agreement with the previous works. According to pollution profile, wastewater generation and pollutant loads as COD are mainly originated from evaporator vapor condensate. The efforts should be on the way to minimize the pollution loading and wastewater generation of this process. Some advices were given for this purpose in the study. For example, recycled cooling water from evaporator may be treated by mechanically instead chemical treatment to reduce energy and water consumptions in the plant. The quality of the final effluent meets the discharge limits of Aquatic Products and Water Pollution Control Regulations of Turkey and European Union (EU) Urban Wastewater Directive for Sensitive Regions. The whole WWTP has been operated very successfully and it is one of the best plants in this sector. The biosolids from the WWTP is planning to produce compost by mixing the residual corn wastes by applying windrow composting. Keywords: Advanced wastewater treatment, corn processing industry, pollution profile, waste minimization

Controlling unequal surface energy results caused by test liquids: the case of UV/O3 Treated PET

Ultraviolet/ozone (UV/O3) treatment has been reported to be an effective method to modify properties such as wettability, adhesion or adsorption of plastic surfaces. The change in the surface is measured by contact angle analysis, which employs liquids and their surface tensions (ST) to estimate the surface energy (SE). We found two different practices in the scientific community: (1) the majority of researchers adopted the ST value of liquids from the literature, while (2) other researchers conducted real-time measurements in the lab under ambient conditions prior to SE estimation. To the best of our knowledge, there is no study that compares the difference between the two practices. One study was found to show different SE methods generating unequal SE values for the same substrate. However, there was no definitive conclusion backed by general thermodynamics rules. In this study, we presented (1) a statistical significance test that showed the literature and experimental ST values are significantly different, and studied (2) the effect of different liquid pairs on the SE estimation for UV/O3 treated poly(ethylene terephthalate) (PET) substrate. Modification techniques such as atmospheric pressure plasma or chemical modification were studied previously to examine PET’s wettability and the SE. The UV/O3 treatment was studied to improve adhesion and to modify its chemical properties for adsorption. In contrast, we studied (3) the effect of UV/O3 on wettability at different timeframes and addressed (4) how to control unequal SE based on a method that was refined on a rigorous thermodynamic three-phase system. It must be noted that this method can be generalized to other types of solid surfaces to estimate thermodynamically self-consistent SE values. This work also provides (5) a web-based calculator that complements computational findings available to the readership in the data availability section

Use of nanoparticle binders for paper coatings: A review

Starch is a biopolymer that is used as a co-binder alongside synthetic petroleum based latex binders for paper coating applications, though it causes production downtimes due to the problems during cooking process, such as gelling; lack of full expansion of starch granules; increase in viscosity during cooling; bacteria growth in cooked starch and difficulties in viscosity control during storage. On the other hand, synthetic binders negatively affect paper recyclability and biodegradability. To overcome these problems, a new biopolymer binder has been introduced to the paper manufacturing, being used initially as a partial replacement for petroleum based synthetic latex polymers. This study reviews the recent developments of nanoparticle biopolymer binders, referred to as biolatex binders. These binders are shipped dry and can be dispersed in water without cooking requirement while improving paper quality and reducing costs of paper manufacturing. They also provide quality benefits, coater runnability improvements and new higher solids coating formulations for future product advancements

Post-traumatic stress disorder after terrorist attack in healthcare professionals

INTRODUCTION: On the date of 15 July 2016 a terrorist organization launched a terrorist attack using helicopters and heavy combat weapons in the city centers of Istanbul and Ankara simultaneously. Numerous civilian were hurt and many of them lost their lives during the attacks. Terrorism is a form of combat designed to cause the highest psychological influence on the masses. Post-traumatic stress disorder (PTSD) is one of the most common psychological disorders after such disasters. The aim of this study is to determine the associated risk factors and PTSD rates in healthcare professionals who were on call during the 15 July 2016 terrorist attacks. METHOD: Since the hospital is in a neighbouring the street to where terror attacks occurred, all healthcare professionals ≥ 18 years of age who were on duty that night in the Dr. Ridvan Ege Training and Research Hospital and were auditory or visual witnesses of the event were included in the study as the first group while healthcare professionals who work in the same hospital but were not on duty that night were included as the control group. RESULTS: The mean post-traumatic diagnostic scale stress score of the control group was 11.87. The mean post-traumatic diagnostic scale stress score of the Group 1 was 21.91. There was a significant difference between the groups in terms of posttraumatic diagnostic scale stress score (p < 0.05). While the healthcare professionals on duty on July 15, 2016 (Group 1) had moderate-severe (21.91 ± 5.11) stress disorder, the healthcare professionals who were not at the hospital on July 15, 2016 (Control Group) had moderate stress disorder (11.87 ± 6.86). CONCLUSION: Our country is at risk from the fact that such attacks may be experienced again because of its unique conditions. The results of our work support the data on the high level of exposure to PTSD when exposed to a terrorist attack. For this reason, the identification of the characteristics of pre-traumatic health individuals at risk is useful in planning the presentation of preventive and curative health services. At the same time, there is a need for longer-term work and wider samples to reveal the psychological consequences of such attacks