Treatability of wastewaters containing complex metal by electrocoagulation process

Toxic metals have been categorized in priority pollutant lists and their proper management is the main subject of recent environmental studies. Conventionally, hydroxide precipitation of metals is being employed for the treatment of metal finishing industry wastewaters. However, effluents bearing complexed heavy metals cannot be efficiently removed by employing precipitation methods. Recent research has demonstrated that electrocoagulation (EC) offers an attractive alternative to conventional treatment methods applied to metal finishing wastewaters. EC is known as an easy-to-operate and efficient electrochemical treatment method preferentially applied to treat "hard" industrial wastewater. EC using stainless steel and aluminum electrodes appears to be an ideal candidate for treatment of wastewaters containing complexed metals. Considering the above indicated facts, the present study focused on the treatability of metal finishing effluent originating from the nickel and zinc plating process by EC using stainless steel electrodes. In order to observe the system's performance as a function of varying process variables such as electrolyte (chloride) concentration, current density (mA/cm2), initial pH of the reaction solution and operation time, the feasibility of the proposed alternative treatment system was evaluated under different working conditions in terms of heavy metal (nickel and zinc) and organic matter (TOC) removal. Generally speaking, the treatment performance of EC  highly dependent upon the pH of the wastewater to be treated and the pH increases from its original pH to alkaline pH values during the course of reaction due to cathodic hydroxide formation. For the evaluation of the effect of initial pH on process performance, a series of experiments were carried out with the effluent at a fixed electrolyte concentration (1615 mg/L chloride) and current density (22.5 mA/cm2) at initial pH values of 3-10. The obtained findings indicated that the overall TOC removals were independent from pH at the studied pH range. On the other hand, heavy metal removal via EC was governed by the effluent pH. This is mainly because the pH value reached at the end of the selected EC operation time (120 min) was in the proper range for zinc and nickel hydroxide precipitation. On the other hand, nickel removal was influenced by the residual TOC and significant nickel removal began after TOC fell below 100 mg/L. The electrolyte concentration increases the conductivity of the reaction solution which in turn reduces the voltage needed to achieve a certain current. The effect of electrolyte concentration on the process performance was also examined. The experiments were conducted with effluent having initial pH of 6.0 at a fixed current density (22.5 mA/cm2) at electrolyte (chloride) concentrations in the range of 1500-3000 mg/L. Increasing the chloride concentration from 1500 to 3000 mg/L accelerated the TOC removals for an operation time of 75 min. However, the actual chloride concentration of the wastewater (1350-1480 mg/L) was adequate for TOC, nickel and zinc removal employing EC. In terms of both treatment efficiencies and electrical energy requirements, the applied current density is the most critical factor and hence key design parameter affecting the treatment systems's response time as well as dominant separation/pollutant mode. For any specific application, the optimal current density has to be determined and will invariably involve a trade-off between operational costs and most efficient use of the produced coagulant. Therefore, a series of EC experiments was carried out with the same effluent at densities varying between 2.25 - 56.25 mA/cm2. For the evaluation of the affect of current density on system performance the original pH (6.0) and chloride concentration (1480 mg/L) of the wastewater were selected. From the experimental results it could be concluded that increasing the current density from 2.25 to 9.0 mA/cm2 dramatically increased TOC removal efficiencies from 20% to 60%. For the higher current densities investigated (22.5-56.25 mA/cm2), the same TOC removal efficiencies could be achieved but at relatively shorter reaction times. Keywords: Electrocoagulation; metal finishing industry, nickel and zinc removal; organic carbon abatement, stainless steel electrodes.Günümüzde ağır metal içeren atıksuların arıtılması gerek bu tip akımların çok çeşitli kaynaklarının olması gerekse kirlenmede taşıdıkları önem nedeniyle dikkatle değerlendirilmesi gereken bir nokta olarak gündeme gelmektedir. Kompleks olarak bağlı metal içeren atıksular, bünyelerinde organik kompleks yapıcıların (organik ligandların) bulunduğu atıksulardır. Henüz bu atıksularının arıtımı için uygun bir arıtma teknolojisi tanımlanmamıştır. Bu çalışmada elektrokoagülasyon prosesinin, metal son işlemleri endüstrisi kompleks olarak bağlı metal içeren atıksularına uygulanabilirliği, bir asidik nikel çinko kaplama banyosundan kaynak bazında alınan atıksu numunesi ile bu işlemi takip eden yıkamaları karakterize etmek üzere hazırlanan kompozit numune (TOK=173-207 mg/L; Ni=275-291 mg/L, Zn=226-236 mg/L) kullanılarak araştırılmıştır. Elektrolit konsantrasyonunun, başlangıç pH sının ve akım yoğunluğunun çinko ve nikel ile birlikte organik madde (TOK) giderimi üzerine etkileri incelenmiş ve değerlendirilmiştir. Deneysel çalışmadan elde edilen sonuçlar; paslanmaz çelik elektrodların kullanıldığı elektrokoagülasyon uygulaması ile söz konusu atıksulardan nikel ve çinkonun % 100 verimle tamamen giderilebildiğini göstermiştir. Başlangıç pH sının ve elektrolit konsantrasyonunun TOK giderimi üzerine önemli bir etkisinin olmadığı ve atıksuyun kendi bünyesindeki klorür konsantrasyonunun elektrokoagülasyon prosesinin işletimi için yeterli olduğu sonucuna varılmıştır. Akım yoğunluğunun etkisinin belirlendiği deneysel çalışmalarda ise 2.25-9.0 mA/cm2 akım yoğunlukları arasında artan akım yoğunluğu ile TOK giderme veriminin arttığı, daha yüksek akım yoğunluklarında (22.5-56.25 mA/cm2 aralığı) ise aynı TOK giderim verimlerine daha kısa sürelerde ulaşıldığı belirlenmiştir. Bu proses ile optimum işletme koşullarında (akım yoğunluğu= 22.5 mA/cm2; başlangıç pH= 6); numunenin kendi bünyesindeki çözünmüş madde konsantrasyonundan elektrolit olarak  faydalanılarak çinko ve nikel tamamen, TOK ise %50 oranında giderilmiştir. Anahtar Kelimeler: Çelik elektrodlar, elektrokoagülasyon, kompleks olarak bağlı metal içeren atıksular, metal son işlemleri endüstrisi,  nikel ve çinko giderimi, organik madde giderimi

Comparison of the Accuracy of Manual and Digital Cephalometric Prediction Methods in Orthognathic Surgical Planning: A Pilot Study

Objective:To compare and evaluate the reliability of manual and digital cephalometric prediction methods in orthognathic surgical planningMethods:Ten adults (5 females and 5 males) with skeletal class III malocclusion were included. The mean patient age was 21.97 years. Pre- to postoperative changes were evaluated using paired t-test. Manual surgical predictions made by tracing on acetate paper and digital predictions made using computer software were compared with actual postoperative values using intraclass correlation coefficient and root mean square.Results:Statistically significant changes were observed in SNA, SNB, ANB, U1i-FH, and Nperp-A following bimaxillary orthognathic surgery (p<0.001). Postoperative changes in Co-A and Nperp-Pg were statistically significant (p<0.05). Comparison of manual and digital surgical predictions with actual postoperative values revealed that overbite and overjet showed the lowest agreements. Manual predictions were less accurate for points that were difficult to distinguish (Co and U6). Skeletal predictions were more accurate than dental predictions.Conclusion:Parameters with low reproducibility (Co and U6) decrease the reliability of predictions. Dental predictions were inaccurate in both methods due to the effects of intermaxillary elastics, but both methods yielded similar predictions for skeletal parameters. The impact of applying strong elastics for postoperative intermaxillary fixation should be considered when making surgical predictions

Evaluation of patients with fibrotic interstitial lung disease: Preliminary results from the Turk-UIP study

OBJECTIVE: Differential diagnosis of idiopathic pulmonary fibrosis (IPF) is important among fibrotic interstitial lung diseases (ILD). This study aimed to evaluate the rate of IPF in patients with fibrotic ILD and to determine the clinical-laboratory features of patients with and without IPF that would provide the differential diagnosis of IPF. MATERIAL AND METHODS: The study included the patients with the usual interstitial pneumonia (UIP) pattern or possible UIP pattern on thorax high-resolution computed tomography, and/or UIP pattern, probable UIP or possible UIP pattern at lung biopsy according to the 2011 ATS/ERSARS/ALAT guidelines. Demographics and clinical and radiological data of the patients were recorded. All data recorded by researchers was evaluated by radiology and the clinical decision board. RESULTS: A total of 336 patients (253 men, 83 women, age 65.8 +/- 9.0 years) were evaluated. Of the patients with sufficient data for diag-nosis (n=300), the diagnosis was IPF in 121 (40.3%), unclassified idiopathic interstitial pneumonia in 50 (16.7%), combined pulmonary fibrosis and emphysema (CPFE) in 40 (13.3%), and lung involvement of connective tissue disease (CTD) in 16 (5.3%). When 29 patients with definite IPF features were added to the patients with CPFE, the total number of IPF patients reached 150 (50%). Rate of male sex (p<0.001), smoking history (p<0.001), and the presence of clubbing (p=0.001) were significantly high in patients with IPE None of the women <50 years and none of the men <50 years of age without a smoking history were diagnosed with IPE Presence of at least 1 of the symptoms suggestive of CTD, erythrocyte sedimentation rate (ESR), and antinuclear antibody (FANA) positivity rates were significantly higher in the non-IPF group (p<0.001, p=0.029, p=0.009, respectively). CONCLUSION: The rate of IPF among patients with fibrotic ILD was 50%. In the differential diagnosis of IPF, sex, smoking habits, and the presence of clubbing are important. The presence of symptoms related to CTD, ESR elevation, and EANA positivity reduce the likelihood of IPF

Geleneksel Mersin evlerinin biçimsel özelliklerinin incelenmesi

TEZ4113Tez (Yüksek Lisans) -- Çukurova Üniversitesi, Adana, 2001.Kaynakça (s. 129-131) var.ix, 132[3] s. ; res. , hrt. ; 30 cm.

Kann der Unternehmensgewinn durch „Spontaneous Recognition“ gesteigert werden?

The Gallup Institute published the results of its Employee Engagement Index study at the end of March, which it has been conducting for 13 years. Again, 85% of the polled participants over the age of 18 do not feel associated to the company they work for. Although the percentage has increased from 11% in 2011 to 16%, the percentage of employees with a high level of emotional attachment to their company is quite low. As Germany has 33,819 million employees over the age of 18, this lack of attachment leads to issues such as absenteeism, employee turnover, work force decline, work-related accidents and quality issues; which in turn increases the costs for the German economy by at least 98.5 billion Euros. What can companies and individual managers do to improve this situation? Can employee commitment/ retention be improved through employee appreciation and recognition and thus increase business profits

The Journal Of Poetry, Number Şr 87, In The Lıbrary Of İstanbul Research Instıtue

Mecmûalar, Türk kültürüne dair pek çok unsuru ihtiva etmektedir. Mecmûza-i eşzârlar ise dîvân şairlerinin şiirlerinin kayıt altına alındığı önemli kaynaklardandır. Bu çalışmanın konusunu, İstanbul Araştırmaları Enstitüsü Kütüphanesinin Şevket Rado Yazmaları bölümünde ŞR 89 ve ŞR 60 numaralarında kayıtlı iki mecmua oluşturmaktadır. Çalışmada öncelikle mecmua metinleri yeni harflere aktırılmıştır ve sonrasında da metinlerin şekil ve muhteva açısından değerlendirilmesi yapılmıştır. İAEKzde kayıtlı ŞR 89 numaralı mecmuada 403 şiir yer almaktadır ve 119 mahlas tespit edilmiştir. Mecmuada yer alan 403 şiirden 96 şiirin mahlası bilinmemektedir. Mecmuayı meydana getiren şiirler, XVI. ve XVII. yüzyıl şairlerinin şiiridir. ŞR 89 numaralı mecmua içerdiği şiirlerin sayısı ve nazım biçimleri bakımından zenginlik arzetmektedir. İAEKzde kayıtlı ŞR 60 mecmuada ise yekûnde 250 şiir bulunmaktadır ve bu 250 şiirden bir tanesi mükerrer olarak yer almaktadır. Bu mecmua, Bakî, Emrî, Necatî, Rahmî, Ubeydî, Ümidî ve Zatî olmak üzere XVI. yüzyıl şairlerinin şiirlerinden müteşekkil bir eserdir. ŞR 60 numaralı mecmua sadece kaside ve gazel nazım biçimlerinin örneklerinden meydana gelmiştir. Tertiplenişi bakımından sistematik bir özellik arz eden mecmuada, her bir şairin şiirleri için ayrı bir bölümün ayrılmış olduğu izlenimine varılmaktadır.The journals contain many elements of the Turkish culture. Journals of poetry are among the important sources of the poems of the Ottoman poets. The subject of this work is constituted by two journals, which are registered in the Şevket Rado Writings section of the Istanbul Researches Institute Library under the numbers 60 and 89 of the Institute. In the study, firstly the journals texts were transferred to the new letters and following that the texts were evaluated in terms of form and content. There are 403 poems in the journal with the Number ŞR 89 which is registered at the IAEK and 119 nicknames have been identified. The nicknames of the 96 poems out of the 403 poems that are taking place in the journal are not known. The poems that are constituting the journal, are the poems of the XVI. and XVII. century poets. The journal with the number ŞR 89 shows richness in terms of the number of poems and the verse forms that it contains. And there are total 250 poems at the journal with the number ŞR 60, which is registered in IAEK, and one poem out of these 250 poems is repeated. This journal is composed of the poems of the XVI. century poets like Bakî, Emrî, Necatî, Rahmî, Ubeydî, Ümidî and Zatî. The journal with the number ŞR 60 is a work composed of samples of ode and lyric poetry format. It is observed that there is a separate section for each poet's poems in the journal, which is displaying a systematic feature in terms of the organization

ŞÎWARİ DÊRSIMÎ

ġiwarî, hetê edebî û tarixî ra kulturê miletî de cayêdo xususî û bîyayîĢe kulturê kirmanckî Dêrsimî de cayê do xorî û rind ceno. ġiwarî, zafane qeza û nêweĢîye ra merdene, keyneke azev û xorto de miradî verde mendî, axa û pîl ke merd, afete tabîî ame sero yan kî ceng û leje mabênê eĢîre de kiĢîyayene, keso ke sono eskerîye labele peynî de nîno sero dînê ameyo vatîĢ. ġiwarî ye kirmanckî tewr zîyade qirkerdayîĢe hîris û heĢt (1938) sero ameyo vatîĢ. VajîyayîĢe Ģiwarî ebe qefîye û aheng ra yeno meydan û ameyo vatîĢ. ġiwarî se torêde lawike caye de rind ceno edebîyate Ģare Kirmanckî de