77 research outputs found

    Nikel kadmiyum sulu çözeltilerinden kadmiyumun sinerjistik ekstraksiyonu

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    06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Kadmiyum, kadmiyum bileşikleri ve kadmiyum alaşımları endüstriyel ve teknolojik açıdan önemlidir. Kadmiyum, kobalt ve nikelin genellikle birlikte bulunması, bu metallerin benzer fiziksel ve kimyasal özelliklere sahip olması ve uygulamalarında yüksek saflık derecesi gerektirmeleri, kadmiyum, kobalt ve nikelin ayrılmasıyla ilgili birçok araştırmanın yapılmasına yol açmıştır. Nikele ve değerli metallere duyulan ihtiyacın sürekli artmasından ve yüksek tenörlü cevherlerin gittikçe azalmasından dolayı çok düşük oranda değerli metal veya metaller içeren katı atıkların ve atık çözeltilerin değerlendirilmesi gerekmektedir. Bundan dolayı, problemin çözümüne katkıda bulunacak yeni proseslerin geliştirilmesi her geçen gün artan bir önem kazanmaktadır.Sulu çözeltilerden kadmiyum ile kobalt ve nikelin ayrılması, geriye kazanılması solvent ekstraksiyonla çok fazla incelenmiş olup, bunların bir kısmı ya endüstriyel olarak işletimde veya işletilmek üzeredir. Genel olarak solvent ekstraksiyonu sulu bir çözeltide bulunan farklı metal iyonlarından arzu edilen metali tercihli olarak ayırmaya yarayan metottur.Bu çalışmada solvent ekstraksiyonu ile asidik çözeltilerden kadmiyum seçici olarak ayrılması incelendi. Sinerjistik ekstraktant olarak triizooktilamin (TIOA) ve tribütilfosfat (TBP) kullanıldı. Ekstraksiyon için çeşitli parametreler (çözücü cinsi, ekstraktant, asit ve potasyum iyodür konsantrasyonu, karıştırma hızı, muamele oranı (Vo/Va), ekstraksiyon süresi) denenerek optimum şartlar belirlendi. Optimum şartlarda değişik Cd/Co/Ni konsantrasyonlarında kadmiyumun ekstraksiyonu gerçekleştirildi. Ekstrakte edilen kadmiyum sodyum hidroksit çözeltisi ile sıyrılarak sulu faza geri kazanıldı.Cadmium and its compounds have found wide range of applications in a number of industrial and technological fields. However, one of the main drawbacks that these compounds have is the separation of cadmium from nickel. These two elements are usually found together, and they have very similar physical and chemical properties, making them very hard to be purified. Moreover, The supply-demand gap for nickel and other valuable ores have been increasing with limited supply and increasing demand. With this in mind, one of the practical solutions to the problem would be recycling of solid and liquid waste containing trace amounts of precious metals, which lately has drawn very much attention. Furthermore, the separation of nickel and cadmium from aqueous solutions by solvent extraction, a method that depends on the selective dissolving of metal ions in aqueous solution, has been overstudied, and found many applications in various industries.In this study, we investigated the selective cadmium extraction from aqueous acidic solutions by solvent extraction. Triisooctylamine (TIOA) and tributylphosphate (TBP) were used as synergistic extractants. After several trials, the optimum extraction conditions (the solvent type, the concentration of the extractant, acid and potasium iodine, the stirring speed, the rate of the reactants (V0/Va), and the extraction time) were found. Under the optimum conditions, the cadmium extraction from the Cd/Co/Ni solutions in various concentrations was performed. The extracted cadmium was transferred back to the aqueous phase by washing with natrium hydroxide solution

    Management of Foreign Body Aspiration in Children: Insights From 664 Cases in the Operating Room

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    Tracheal or bronchial foreign body aspiration is an important emergency o childhood requiring bronchoscopy under general anesthesia. In this retrospective study, bronchoscopy were performed for foreign body aspiration; anesthesia methods, risks, and postoperative complications were evaluated. Children who underwent bronchoscopy with suspicion of a foreign body in the pediatric surgery operating room between January 2010 and December 2021 were included in the study. Six hundred and sixty four children were evaluated. General anesthesia was applied to all bronchoscopy. Demographic characteristics of the patients, type of foreign body, localization of foreign body, distribution of foreign body according to age groups, complications related to anesthesia and surgical process, length of stay in the postoperative intensive care unit, and duration of hospital stay were evaluated. The patients who aspirated foreign bodies most frequently were children aged 1-3 years (73.6%). During bronchoscopy, organic matter (seeds, hazelnuts, peanuts, chickpeas) was the most frequently removed foreign body in children (559 patients). It was observed that foreign bodies were mostly located in the right main bronchus at a rate of 52.4%, the left main bronchus at 28%. The most common anesthesia-related complications were desaturation in 400 patients, hypercarbia in 200 patients, bronchospasm in 108 patients, and respiratory arrest in 2 patients. Many problems may be encountered in foreign body inhalation, and bronchoscopy of these patients should be performed by an experienced anesthesiologist and surgeon at the right time and in the safest way in terms of anesthesia and surgery

    2023'e Doğru Türkiye'de Üniversite Kütüphaneleri : Mevcut Durum, Sorunlar, Standartlar ve Çözüm Önerileri

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    Çağın gereklerine uygun ve dünya ile rekabet edebilir bir eğitim, öğretim ve araştırma altyapısı için üniversitelerin en azından kendi alanlarında üretilen bilgiye erişebilecek ve bu bilgiyi 7/24 kullanıcıların hizmetine sunabilecek altyapıya sahip olmaları gerekir. Bu altyapıdan yoksun bir üniversitede dünyanın bilgi ve deneyiminden yeterince yararlanılamadığı ve hatta daha önce üretilmiş bilgi ve deneyimleri tekrar üretmek üzere gereksiz yere zaman ve para harcadığı ileri sürülebilir. Oysa dünyadaki söz sahibi üniversitelere bakıldığında, bu üniversitelerin kütüphanelerine ciddi yatırımlar yaptıkları ve bu yatırımların sürüdürülebilir olması için gerekli önlemleri aldıkları görülür

    Development and Validation of a Multilingual Lexicon as a Key Tool for the Sensory Analyses and Consumer Tests of Blueberry and Raspberry Fruit

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    A comprehensive lexicon is a necessary communication tool between the panel leader and panelists to describe each sensory stimulus potentially evoked by a product. In the current scientific breeding and trading scenario, a multilingual sensory lexicon is necessary to ensure the consistency of sensory evaluations when tests are conducted across countries and/or with international panelists. This study aimed to develop a reference multilingual lexicon for raspberry (Rubus idaeus L.) and blueberry (Vaccinium corymbosum L.) to perform comparative sensory tests through panels operating in different countries using their native language. Attributes were collected from state-of-the-art literature and integrated with a detailed description of the sensory stimulus associated with each term. A panel of sensory judges was trained to test lexicon efficacy. After training, panelists evaluated three cultivars of blueberry and raspberry through RATA (Rate All That Apply), which allowed missing attributes to be excluded while rating those actually present. Results showed the discerning efficacy of the lexicon developed can be a valuable tool for planning sensory evaluations held in different countries, opening up further possibilities to enrich blueberry and raspberry descriptor lists with emerging terms from local experience and evaluations of berry genotypes with peculiar traits.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101000747. Partial funding for open access charge: Universidad de Málaga

    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

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    Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

    Markalama Stratejilerine Genel Bir Bakış

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