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Copyright of Afyon Kocatepe University Journal of Science & Engineering / Afyon Kocatepe Üniversitesi Fen Ve Mühendislik Bilimleri Dergisi is the property of Afyon Kocatepe University, Faculty of Science & Literature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Mining activities can produce large amounts of heavy metals that are discharged uncontrollably, causing widespread ecosystem pollution. Heavy metal pollution is a serious problem, as heavy metals are toxic and non-degradable, polluting air, water and soil. Although some heavy metals are considered essential for normal physiological functions, concentrations that exceed the prescribed limits can have negative impacts on human health and biota. Exposure to heavy metals can cause toxicity to various tissues, organs and systems such as circulatory, respiratory, endocrine, immune, nervous, urinary and reproductive systems. Due to the differences in toxicity of heavy metals, risk assessment is very important in environmental management. Objective: To describe the probabilistic simulation and sensitivity of health risks due to Nickel and Cobalt deposition around the mine using monte carlo simulation. Methods: The method used in this study was literature review. Data collection was done through searching online databases such as: Pubmed and Science Direct. The keywords used in the article search were "Heavy Metal Toxicity", "Heavy Metal Effects", "Heavy metal risk analysis" and "Monte Carlo Simulation". Inclusion criteria were quantitative or qualitative research, target population was heavy metals Nickel and Cobalt, published in the last 10 years (2013-2023) articles in English and articles in original, fulltext and open access. Exclusion criteria are articles that are not relevant to the topic of discussion. Results: 14 articles were found, of which 3 articles on diseases or health problems caused by nickel, 3 articles on nickel risk analysis, 5 articles on diseases or health problems caused by cobalt, 3 articles on cobalt risk analysis. Conclusion: The environment around the mine shows a high level of toxicity, caused by the presence of heavy metals. This can result in serious environmental pollution and pose a great threat to human health. Chronic exposure to heavy metals can cause various health problems, such as mutagenesis, carcinogenesis, teratogenesis, deformation and organ damage. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop metal-metal composites reinforced with nickel powder using an AA5083 aluminium alloy matrix by powder metallurgy methods and to investigate their properties. In order to analyse the influence of different amounts of nickel particles on the AA5083-Ni composite, specimens were prepared by incorporating nickel at 5%, 10% and 15% by weight. To achieve a uniform distribution of nickel particles, the matrix and composite powders were mixed in ball mills for five hours. These powders were then hot pressed at 500°C under a pressure of 500 MPa for two hours in an argon gas atmosphere to produce the samples. These samples were then tested for microstructure, hardness, density, tensile properties and corrosion behaviour to assess the effect of varying nickel content on the AA5083-Ni metal-metal composites. [ABSTRACT FROM AUTHOR]

Smelting atau peleburan adalah proses mengekstraksi bijih logam murni dari dalam tanah. Dengan kata lain, ini adalah proses pemisahan logam murni dari bijih yang mengandungnya. Untuk mengekstraksi logam, bijih dipanaskan hingga suhu tinggi (di atas titik lelehnya). Untuk proses ini digunakan smelter yang dalam prosesnya akan menghasilkan limbah cair dan limbah padat (sludge). Sludge tersebut biasanya digunakan sebagai penutup lubang bekas tambang. Sludge digunakan sebagai material dasar pembentuk paving block untuk mengurangi limbah dan peningkatan nilai ekonomis. Pada penelitian ini sludge atau lumpur digunakan sebagai pengganti pasir pada produksi paving block. Kadar sludge yang digunakan adalah 10%, 25% dan 50% menggantikan volume pasir, paving block tanpa sludge sebagai benda uji kontrol. Untuk mengetahui mutu paving block yang dihasilkan dilakukan pengujian kuat tekan dan penyerapan. Hasil penelitian menunjukkan bahwa paving block dengan kadar 10% menghasilkan paving block mutu B, pada kadar 25% dan 50% menghasilkan paving block mutu C.

In this study, new poly(HEMA-co-GMA) or pHEMA-GMA support solid structures were prepared to help protein purification. The surface of the prepared pHEMA-GMA building materials was modified by binding different functional groups such as IDA and NTA. Nickel (Ni II) metal ion was passed through the modified cryogel structures. The monolithic cryogel structure chelated with Ni metal was characterized by SEM and FT-IR. GFP fluorescent protein binding studies of metal chelated cryogel structures were performed using UV-vis and fluorescence spectrophotometry. These cryogels were determined to bind 45% and 75% protein by UV-vis and fluorescence spectrophotometry. And these results were supported by visualization with the SDS PAGE method. [ABSTRACT FROM AUTHOR]

In this study, a series of adsorption studies were carried out for the concentration range of 18.08 - 183.95 mg/L Ni(II) in metal plating industry wastewater using graphene oxide. Under constant stirring speed of 200 rpm, optimum pH=6 and optimum contact time was found to be 90 minutes. Temkin isotherm as a pseudo 2nd order kinetic isotherm was chosen as the appropriate model for adsorption kinetics. The optimum amount of graphene oxide as adsorbent was determined as 0.016 mg/L and accordingly the maximum adsorption capacity was 112.56 mg/g. Considering the literature comparisons; it was concluded that graphene oxide can be used as an improvable adsorbent, however, high efficiency cannot be obtained alone, but high efficiency can be achieved with graphene oxide if it is functionalized. [ABSTRACT FROM AUTHOR]

Bimetallic catalysts based on ZSM-5 zeolite modified with ytterbium and nickel have been prepared. The influence of the concentration of ytterbium (1.7-5.0 wt.%) and nickel (1.0-1.5 wt.%) on the acidic, textural and catalytic properties of the zeolite in the reaction of alkylation of toluene with isopropanol in the temperature range of 300-350℃ was studied. It has been shown that the unmodified zeolite HZSM-5 exhibits low selectivity (54.6-58.2%) for isopropyltoluenes (3-IPT, 4-IPT, and 2-IPT) than the modified catalysts. In addition, the content of the valuable 4-IPT isomer does not exceed 44.2%. Modification of HZSM-5 with ytterbium in an amount of 5.0 wt.% leads to an increase in the selectivity for isopropyltoluenes up to 68.7%, and the selectivity for 4-IPT up to 68.8%. Additional modification of the 3%-Yb-HZSM-5 catalyst with nickel in the amount of 1.0 wt.% prevents the formation of 2-IPT and promotes an increase in the yield of 4-IPT. The modified catalysts were characterized by XPA, BET, BJH, and ammonia TPD. Modification, calcination, and successive treatment of the catalyst with air and hydrogen leads to a dispersed distribution of Yb2O3 and metallic nickel oxide nanoparticles in the outer surface and in the pores of the zeolite, which causes a decrease in the specific surface area, total pore volume, and an increase in the fraction of mesopore volume. As a result of the interaction of modifiers with acidic OH groups of the zeolite, the concentration of strong Brønsted acid sites decreases and new, stronger Lewis acid sites form. All this has a decisive effect on the selectivity of 4-IPT formation and the stability of the bimetallic catalyst. The maximum selectivity for 4-IPT on a 3% Yb 1.0% Ni/HZSM-5 bimetallic catalyst is achieved at 3300C and is 71.5% at a toluene conversion of 24.6%. [ABSTRACT FROM AUTHOR]

Copyright of Jurnal Hubungan Internasional is the property of Universitas Airlangga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Kocatepe Veterinary Journal / Kocatepe Veteriner Dergisi is the property of Afyon Kocatepe University, Faculty of Veterinary Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Yenilenebilir enerji kaynaklarından biri olan biyogaz enerjisi Türkiye’de yeni gelişmekte olan bir sektör haline gelmiştir. Türkiye’de mevcut biyogaz reaktörleri genellikle sürekli tip reaktörler olup substrat olarak sığır gübresi (SG) kullanmaktadır. Yapılan araştırmalara göre SG’nin biyogaz verimi literatürdeki verimlerinden oldukça düşük değerde (50-100 ml/g uçucu katı (UKSG)) çıkmaktadır. Bu nedenle SG’nin verimini artırmaya yönelik olan bu çalışma yapılmıştır. Bu bağlamda SG’nin biyogaz verimi laboratuvar ölçekli 5L’lik bir reaktörde endüstriyel reaktörlerin en çok kullandığı çalışma sıcaklığında (35 °C) test edilmiştir. Bu reaktör kontrol reaktörü olarak belirlendikten sonra çözünür karbonhidrat, protein ve yağlardan arınmış ve çoğunlukla lignoselülozik içeren reaktör kalıntısına %4 m/m NaOH ön işlemi ve sonrasında katalitik metallerden olan nikel (Ni) ve kobalt (Co) farklı konsantrasyonlarda (50, 100 ve 150 µg/toplam katı SG) eklenmiştir. Bu sayede kontrol reaktörüne kıyasla, bu metallerin belirli konsantrasyonun eklenmesi ile hidrojenotrofik aktiviteyi uyarabilen ve biyogaz üretimini daha da artırabilen bir sonuçla (%36 - 47) karşılaşılmıştır. En iyi Ni ve Co konsantrasyonu için SG’nin en yüksek biyogaz verimi toplam 509,5 ± 19,9 ml/g UK olmuştur.

Spectrophotometric methods are used to study the reaction of the nickel complex with 2.4- tyazolidindico (L) and its derivatives {5- (gasilysiliden) -2,4-tyazolidindio (L1), 5- (2-chlorbenzyliden) -2,4- tyazolidindion (L2), 5-(2-hydroxybenzylide) -2,4-tiazoleader (L3), 5- (4-hydroxybenzylide)-2,4- tyazolidindion(L4),5-(2-Brom-5-methoxybenzyiliden)-2,4-tiazolyidinedion (L5). With a single extraction, the chloroform is extracted by 97.8-98.4 % of the nickel. The study of the dependence of complexation on pH showed that the optimal range of acidity, at which the optical density is maximum and constant, is at pH 2.3- 8.0. The optimal condition for the formation and extraction of the nickel complex of these compounds is (2.0- 2.5) × 10-4 M concentration L. Nickel complexes with L are stable in water and organic solvents and do not decompose for three days, and after extraction for more than a month. The maximum optical density is achieved within 5 minutes. The maximum analytical signal during the complex of nickel L is observed at 470-482 nm/ molar absorption coefficients (1.37-1.61)×104 . The comprehensive form of nickel is Ni2*while the number of protons supplanted by it from one molecule L turned out to be equal to 1. Nickel and its complexes in the organic phase are not polymerized and are in a monomeric form (γ = 1.01-1.07). The proposed method under already established optimal conditions is used to determine Ni (II) in wastewater, bottom deposits, as well as in oil and oil products. [ABSTRACT FROM AUTHOR]

Tropical peat with low bulk density affects the ability of peat soil to support plant growth. To improve the bulk density of peat, mineral soil is mixed to peat soil. However, mineral soil sources near peatlands are typically ultrabasic parent material with high nickel (Ni) content up to 5000 ppm. The acidic peat condition and low topography of peatlands may increase the solubility of Ni if in flooding condition. Therefore, mixing soil materials and water treatments are aimed at measuring Ni solubility at pH equilibrium after mixing and extracting using NH4OAc 1.0 N pH 7.0; 4.8; 4.2, HCl 1.0 N; 0.1 N, and H2SO4 1.0 N. The pH equilibrium after mixing soil materials was at pH 5.2-6.1, indicating Ni solubility is shown by the results of NH4OAc 1.0 N pH 7.0 - 4.8 extraction. Within this pH range, the Ni solubility value in the saturation (J) and drying (K) treatments did not differ significantly at a 5% level of significance. However, the Ni solubility with each addition of peat weight differed significantly under the saturated and moist-dried conditions (JK). [ABSTRACT FROM AUTHOR]

In this study, removal of heavy metals from wastewaters by chemical precipitation using calcined Black Sea mussel shells was investigated. The mussel shell used was primarily powdered and then calcined mussel shell powder was obtained by applying calcination pretreatment, and this material was used in removal studies of lead, nickel, and copper heavy metals. The chemical precipitation performance of conventional calcium hydroxide and sodium hydroxide chemicals was also examined to make a comparison in the studies. The most suitable treatment conditions were determined by conducting dosage and initial heavy metal concentration experiments for all precipitating agents. As a result of experiments, high treatment efficiencies such as 98.79, 99.67 and 99.37% were achieved in treatment of lead, nickel, and copper heavy metals by calcined mussel shell powder, respectively. It has been determined that effective heavy metal removal can be achieved at close dosages of calcined mussel shell powder and other chemicals. Mussel shell caused to obtain lower final pH values despite providing these higher efficiencies. When all these factors are considered together, it has been exhibited that calcined mussel shell powder can be an alternative to other precipitating agents because it is a natural material and abundant in nature. [ABSTRACT FROM AUTHOR]

In recent days, studies on battery technology, which has a very popular place and is developing rapidly, continue intensively. Nickel, which is one of the important raw materials of batteries and whose fields of use are expanding gradually thanks to its physical and chemical properties, is widely used in the production of alloys with various metals, turbine production, battery, paint additive and catalyst production. There are approximately 140 million tons of nickel reserves and 7 million tons of cobalt reserves in the world, 60% of which are lateritic and 40% are sulphides. Although the reserve amount is higher, 42% of the nickel production is made of lateritic 58% of the sulphide ores. However, due to the decrease in the amount of sulphide ores over time, studies on developing technically and economically suitable production methods from lateritic ores have been intensified. Industrially, nickel and cobalt are recovered from lateritic ores by pressurized acid leaching. Atmospheric leaching is both cheaper and safer than the pressure leaching method if long leaching time, high acid consumption and selectivity can be solved. In this study, leaching behavior of Gördes lateritic ore mixture of 70% limonite and 30% non-tronite with both sulfuric acid and phosphoric acid was investigated in atmospheric conditions. Selectivity was provided against nickel and cobalt both by pre-heat treatment to the ore and step leaching process. With the using phosphoric acid, passing through the liquid efficiency of iron was reduced by about 80% compared to using sulfuric acid. Nickel and cobalt yields also obtained in high pressure acid leaching were achieved by sequential leaching and leaching of leaching solids. [ABSTRACT FROM AUTHOR]

Copyright of Balikesir Health Sciences Journal / Balıkesir Sağlık Bilimleri Dergisi is the property of Balikesir Health Sciences Journal (BAUN Health Sci J) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Catalytic cracking adalah proses konversi dengan memotong rantai karbon molekul minyak menjadi hidrokarbon sederhana. Proses pemutusan rantai hidrokarbon bisa dilakukan dengan cara kimia menggunakan katalis dan gas hidrogen. Jenis katalis yang biasa digunakan dalam industri kimia adalah logam seperti Nikel (Ni), seng (Zn), dan kadmium (Cd). Logam tersebut dapat digunakan sebagai katalis secara langsung, tetapi pada saat proses catalytic cracking akan menyebabkan penggumpalan katalis, sehingga tidak bisa digunakan secara berulang. Oleh karena itu, katalis logam harus diimpregnasi ke dalam bahan pengemban seperti zeolit. Penelitian ini bertujuan mempelajari proses preparasi dan karakterisasi katalis zeolit alam aktif impregnasi logam nikel (ZAA/Ni) yang terdiri atas karakteristikluas permukaan, XRD, dan FTIR serta morfologi untuk mendapatkan katalis yang terbaik. Zeolit yang digunakan dalam penelitian ini adalah zeolit dari Bayah Banten yang sudah diaktifasi. Fungsi katalis sebagai pemutus rantai karbon dapat ditingkatkan dengan adanya pengemban, yaitu logam nikel. Pengembang berperan sebagai tempat tersebarnya inti aktif yang dapat meningkatkan efektifitas katalis, sehingga katalis dapat dipergunakan secara berulang. Hasil penelitian menunjukkan ZAA/Ni, rasio Si/Al yang tertinggi adalah 6,66 yang termasuk katalis intermediate dengan rasio Si/Al = 2 – 10. Luas permukaan katalis terluas adalah pada ZAA/Ni 3 % sebesar 974,44 m2/g, nilai kristalinitas terbesar adalah 70,09%. Zeolit asal Bayah Banten yang sudah diimpregnasi logam nikel dapat digunakan sebagai katalis untuk meningkatkan kualitas (upgrading) bio oil menjadi bahan bakar dengan konsentrasi ZAA/Ni 3%.

In this study, nickel was coated as a thin film on the slide by magnetron sputtering and used as a catalyst for alkali potassium borohydride hydrolysis. The effects of parameters such as ambient temperature, catalyst amount, wt% KBH4 ratio, volume of HCl and wt% NaOH ratio rate on the hydrogen production rate in the catalytic hydrolysis of potassium borohydride solution were investigated in detail by response surface method. Process optimization was done using central composite design and the efficiency of the parameters was determined by analysis of variance. As a result of the model created, the optimum parameters for the maximum HGR value; ambient temperature 55 °C; 13% KBH4; 0.6% NaOH; Determined as 9 mL of 0.5 M HCl. The maximum hydrogen generation rate was calculated as 92.8 L/min g. [ABSTRACT FROM AUTHOR]

Plastics, which occupy a large place in our lives, have also brought along various environmental problems with their widespread use. Microplastics can accumulate in the sewage sludge of Wastewater Treatment Plants, and then the use of these sludges in agricultural lands may cause the spread of pollutants such as heavy metals and microplastics for which the toxic effects are not clear, yet. Nickel is one of the heavy metals that pose a risk in agricultural lands, and it is also limited by the relevant regulations. However, the change in the toxicity of Nickel in the presence of potential pollutants such as microplastics and biosolids, whose effects have just begun to be investigated, has not been examined. In this context, nickel toxicity was investigated in the presence of microplastics and biosolids. The effects on reproduction on E. Crypticus, which is used as a representative of living things living in the soil, were determined by EC50 values. Accordingly, both microplastics and biosolids applications had a decreasing effect on Nickel toxicity. This can be explained by the neutralization of Nickel for which toxicity is sourced from ion forms by complexing with organic substances in the biosolid or interacting with charged surface groups that may be present on the microplastic surface. [ABSTRACT FROM AUTHOR]

Bu araştırmada, brokoli bitkisinin tohum ve fidelerinde değişen konsantrasyonlardaki nikelin etkisi ve birikimi incelenmiştir. Tohumlarda çimlenme yüzdesi, bitkinin kök-gövde uzunlukları, ağırlık miktarları, klorofil, karotenoid, total çözünebilir protein ile MDA içerikleri, POD aktiviteleri ve Ni birikimi belirlenmiştir. 100 μM NiSO4 ün tohumlarda çimlenmeyi inhibe ettiği gözlenmiştir. Ni’nin büyümeyi etkilediği, ağırlık miktarlarında da değişikliklere neden olduğu belirlenmiştir. 9 günlük fidelerin klorofil içerikleri 1 μM NiSO4 de artarken, 30 günlük fidelerde ise 0.1 μM NiSO4 de artış tespit edilmiştir. Fidelerdeki total çözünebilir protein içeriğinde 10 ve 100 μM NiSO4 de azalışlar gözlenirken, POD aktivitesinde artışlar gözlenmiştir. Ayrıca, nikelin özellikle köklerde biriktiği belirlenmiştir. Nikelin brokolinin çimlenme ve büyüme-gelişmesi üzerine olan etkileri ile ilgili olarak, düşük konsantrasyonlardan (0.01, 0.1 ve 1 μM) bitkinin olumlu etkilendiği, yüksek konsantrasyonların ise (10 ve 100 μM) toksik etkilere neden olduğu tespit edilmiştir.Anahtar Kelimeler: Nikel, Çimlenme, Bitki büyümesi, Brokoli, Brassica oleracea L. var. italica, Metal birikimi

Arang aktif yang berasal dari biomassa dapat dimanfaatkan untuk berbagai aplikasi, karena memiliki porositas yang tinggi. Salah satu pemanfaatan arang aktif adalah sebagai bahan baku katalis. Arang aktif dalam penelitian ini berasal dari tandan kosong kelapa sawit (TKKS ). Tujuan penelitian ini adalah untuk menentukan karakteristik arang aktif yang dimpregnasi logam Nikel (Ni) sebagai bahan baku katalis dalam proses upgrading bio oil. Aktivasi arang TKKS menggunakan larutan asam fosfat (H3PO4) dengan konsentrasi 10%, 15% dan 20% yang direndam selama 24 jam, dilanjutkan dengan kalsinasi pada suhu 750°C dan steam uap selama 60 menit. Aktivasi terbaik dari arang aktif menggunakan asam fosfat 10%, selanjutnya diimpregnasi logam nikel dengan konsentrasi 1%, 2%, 3%. Hasil karakteristik arang aktif impregnasi logam nikel adalah daya serap iodin554-756 mg/g, daya serap metilen biru 38-90 mg/g dan luas permukaan 96-218 m2/g dengan diameter pori 8,48-16,21 µ.

Heritage is commonly understood as denoting sites, objects and traditions that are selected and protected for their uniqueness, monumentality, beauty and/or historical and cultural significance. Heritage, thus, is almost by definition something unquestionably valuable and good, and of outmost importance for our wellbeing and identity. This paper takes a different position and asks what happens if we question heritage's status as a selected reserve of desired things and traditions. Based on fieldwork conducted in contemporary settlements in the Russian North, it explores how the role and significance we ascribe heritage may come out radically altered upon facing the unruly legacies of the Soviet past. [ABSTRACT FROM AUTHOR]

Copyright of Karaelmas Science & Engineering Journal / Karaelmas Fen ve Mühendislik Dergisi is the property of Karaelmas Science & Engineering Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Karaelmas Science & Engineering Journal / Karaelmas Fen ve Mühendislik Dergisi is the property of Karaelmas Science & Engineering Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The complexation reactions of nickel (II) with 2-hydroxythiophenol and its derivatives (2,5- dihydroxythiophenol, 2-hydroxy-5-chlorothiophenol, 2-hydroxy-5-bromothiophenol, and 2-hydroxy-5- iodothiophenol) in the presence of hydrophobic amines were studied by spectrophotometric methods. Aniline and N, N-dimethylaniline were used as hydrophobic amines. It found that mixed-ligand complexes (MLC) are formed in a weakly acidic medium (pH 2.3-8.0). The maximum in the light absorption spectrum of the complexes is observed at λ = 620-650 nm. The molar coefficients of light absorption are (4.1-4.3)×104 . The best extractants were chloroform, dichloroethane and carbon tetrachloride. With a single extraction with chloroform, 97.8-98.4% of nickel is extracted in the form of MLC. Based on the data obtained, photometric methods for the determination of nickel in various objects were developed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The complexation reaction of nickel with 1-(2-pyridylazo)-2- hydroxy-4-mercaptophenol (PAGMP) in the presence of aminophenols (AP) was studied by spectrophotometric methods. Out of aminophenols there were used 2-(N,N-dimethylaminomethyl)-4-methylphenol and 2-(N, N-dimethylaminomethyl)-4- chlorophenol. We revealed optimum conditions for formation and extraction of differently ligand compounds and determined proportions of components in the complexes. It found that the complexes were formed in a weakly acidic environment (pH 3.5-6.5). The maximum in the light absorption spectrum is observed at λ=620-650 nm. The molar coefficient of light absorption is ε=(2.3-2.5)×104. The optimal condition for the formation and extraction of these compounds is the concentration (1.2-1.5)×10-3 M PAGMP and (2.4- 2.6)×10-3 M AP. The maximum optical density is obtained within 15 minutes. Nickel МLC extracts with PAGMP and AF are subject to Beer's law at concentrations of 0.5–18 μg/ml. Proceeding from the results obtained, the photometric methods for the determination of nickel in water and soil were developed. [ABSTRACT FROM AUTHOR]

Copyright of Osmangazi Journal of Medicine / Osmangazi Tip Dergisi is the property of Eskisehir Osmangazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Silicon nanowire (SiNW) merupakan material berstruktur nano yang pemanfaatannya cukup luas, diantaranya yaitu sebagai material divais elektronik, sebagai material biosensor, dan sebagai sistem pembawa obat. Penumbuhan SiNW salah satunya dapat dilakukan dengan metode PECVD (plasma-enhanced chemical vapor deposition). Nikel digunakan sebagai katalis dalam penumbuhan SiNW pada penelitian ini. Lapisan tipis nikel diberi perlakuan annealing pada suhu 600°C selama 6 jam untuk memperoleh butiran nikel sebagai pemandu tumbuhnya nanowire. Penumbuhan SiNW dilakukan dengan metode PECVD dengan memvariasikan daya frekuensi radio (RF) reaktor sebesar 8 watt, 10 watt, dan 20 watt. Diameter rata-rata untuk daya 8 watt, 10 watt, dan 20 watt berturut-turut adalah 1143,17 nm; 1490,27 nm; dan 2605,26 nm. Morfologi permukaan dilihat dengan pencitraan scanning electron microscope (SEM). Rasio aspek wire dengan daya RF penumbuhan 8 watt, 10 watt, dan 20 watt diinvestigasi dengan pencitraan SEM penampang lintang dengan hasil berturut-turut sebesar 23,3; 3,13; dan 0,33.

Metanollü yakıt hücreleri için yüksek sıralı ve kaliteli TiO2 nano-tüpler (TiO2-NTs) katalizör desteği olarak hazırlanmıştır. Sıralı TiO2-NTs hazırlandıktan sonra yüzeyine küçük miktarlarda nikel (Ni) nanotanecikleri (TiO2-NTs-Ni) elektrokimyasal olarak çöktürülmüştür. Bu şekilde hazırlanan anot katalizörlerinin yüzey ve kristal yapısı sırasıyla taramalı elektron mikroskobu (SEM), dönüşümlü voltametri (CV) ve X-ışını kırınımı (XRD) ile karakterize edilmiştir. Hazırlanan TiO2-NTs-Ni anot katalizörlerinin metanol oksidasyonu için katalitik aktiviteleri 1 M KOH içeren 1 M Metanol çözeltisinde CV ve zamanla kararlılıkları ve dayanıklıkları kronoamperometri (CA) tekniği ile araştırılmıştır. Elde edilen sonuçlara göre TiO2-NTs metanollü ortamda aktivite göstermemiş bununla beraber yüzeyi az miktarda Ni ile kaplanması metanol oksidasyonunu arttırmıştır. Katalizör yüzeyindeki Ni miktarı arttıkça oksidasyon hızı artmaktadır. CV tarama hızı arttıkça oksidasyon pik akımlarında artış gözlemlenmiştir. CA sonuçlarına göre hazırlanan katalizörler bir saat boyunca çalışılan ortamda kararlı ve dayanıklı yapı sergilemiştir. Hazırlanan TiO2-NTs-Ni metanollü yakıt hücreleri için etkin bir anot katalizörü olarak kullanılabilir.

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nickel is a micronutrient for plants and fulfills a variety of essential roles in plants at low concentrations. Nickel is a constituent in the active site of several metallo-enzymes. Therefore, Ni deficiency produces some effects on growth and metabolism of plants including reduced growth, induction of senescence and leaf chlorosis, alterations in N metabolism, reduced Fe uptake, reduced scavenging of superoxide free radical. Although Ni is physiologically important in plants, it is toxic to most plant species when present at excessive amount in soil. Toxicity symptoms of nickel are inhibition of seed germination, photosynthesis and transpiration, disruption of mineral uptake and mitotic activity and ultrastructural changes in different plant organs. In this review, occurence of nickel in nature and its contamination, physiological role and effects of nickel toxicity in plants are discussed. [ABSTRACT FROM AUTHOR]

In this study, polyaniline/sugar beet pulp (PANI/SBP) composites were synthesized, and the potential use of composites was determined for the removal of copper [Cu (II)] and nickel [Ni (II)] from wastewater. The structural and morphological properties of composites were determined by Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM), respectively. The metal removal of composites from aqueous solutions was monitored by Ultraviolet Visible Absorption Spectrometer (UV-Vis). At this stage, some parameters, such as adsorbent dosage, stirring speed and contact time, the initial concentration of metal solutions and pH, were changed, and the most suitable condition was selected for metal removal. Metal removal from wastewater was determined by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) at optimum conditions. FTIR and SEM results supported the formation of PANI/SBP composites. Under optimum conditions, ICP-OES results for wastewater treated with PANI/SBP composite showed that this composite can be used for the removal of copper and nickel from wastewater. [ABSTRACT FROM AUTHOR]

The study aimed at screening and characterization of common bacteria resistant to the toxicity of heavy metals from surface sediment of the Euphrates river, Iraq. The bacterial isolates were identified as Pseudomonas aeruginosa based on their morphological, cultural, biochemical characteristics and chromogenic. Growth of the bacteria isolated and heavy metal degradation was conducted by using UV spectrophotometer and atomic absorption spectrophotometer (AAS). P. aeruginosa has high resistance for chromium and nikel in different stations of Euphrates river ranging within concentration 250 ppb. The isolate P. aeruginosa has moderate chromium degrading ability with average 40.0%. On the other hand, it shows high nickel degrading ability nickel with average of 66.8%. In addition, it was resistance and sensitive to antibiotics in the present study. In conclusion, the results exhibited suggested that P. aeruginosa was an efficient and helpful for heavy metal bioremediation in the aquatic environment. [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ege University School of Dentistry / Ege Üniversitesi Dis Hekimligi Fakültesi Dergisi is the property of Ege University Faculty of Dentistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: In recent years, biotechnological methods are preferred instead of classical methods used in wastewater treatment in order to eliminate or reduce the negative effects of wastes on the environment arising from industrial and technological developments. Pseudomonas spp. are preferred in environmental biotechnology studies because of their ability to remove pollutant factors that cause serious environmental pollution. In this study, the removal mechanism of lead and nickel metals which are toxic for humans and other living organisms were investigated with 40 Pseudomonas genus bacteria which isolated from waste water. With this study, it is aimed to contribute to the removal works of heavy metals in industrial and domestic wastewater by living microorganisms. Methods: 40 Pseudomonas spp. which were isolated from the pools of wastewater treatment plant, have tolerance and resistance tests for lead and nickel. Bioaccumulation tests were performed using the determined LC50 values and the removal of metal ions by the Pseudomonas spp. was evaluated as cell uptake and cell surface involvement. Results: 22 isolates were identified as P. aeruginosa, 11 were P. stutzeri and seven were P. mendocina After incubation of bacteria strains at 37°C for 24 hours in media containing 50 ppm metal, the most resistant five isolates were determined for each metal. For determination of metal tolerances, Pseudomonas spp. are incubated at 37°C for 24 hours on separate media containing 50 ppm, 100 ppm, 200 ppm and 400 ppm lead and nickel and the % of death and LC50 values were calculated. According to results of this study, it was determined that isolates highest metal tolerance for Pb (+2) is P. aeruginosa BK14 and for Ni (+2) is P. stutzeri BK23. Bioaccumulative assays were performed at 10, 30 minutes and at the 1st, 2nd, 4th, 8th, 12th, 16th, 20th and 24th hours, respectively. Removal of the metals was carried out on the cell surface by adsorption and cell uptake. P. aeruginosa BK14 strain removed 84% of 204,30 ppm Pb (+2) in total, as which 56% of on the cell surface and P. stutzeri BK23 strain removed the 76% of 186,21 ppm Ni (+2) in total, as which 47% of on the cell surface. Conclusion: According to the results obtained, the removal of both metals was mostly due to the attachment to the cell surface. In this study, the heavy metal removal mechanism with live Pseudomonas spp.which resistant to lead and nickel was evaluated as comparative to cell surface attachment and cell uptake for the first time. [ABSTRACT FROM AUTHOR]

Copyright of Dicle University Journal of Engineering / Dicle Üniversitesi Mühendislik Dergisi is the property of Dicle Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bu çalışmada, mezogözenekli alümina destekli bimetalik Ni ve Co katalizörler sıralı emdirme yöntemiyle hazırlanmışlardır. Hazırlanan mezogözenekli bimetalik katalizörlerin aktiviteleri 750 oC'de metanın kuru reformlanma reaksiyonunda test edilmiştir. Katalizörlerin reaksiyon öncesi ve/veya sonrası N2 adsorpsiyon/desorpsiyon, XRD, TPR, SEM/EDX ve TG/DT analizleri yürütülmüştür. TPR analizleri, Ni ve Co metallerinin katalizör yapısına emdirme sırasının katalizör yapısındaki metallerin indirgenebilirliğini etkilediğini göstermiştir. Co-Ni içerikli bimetalik katalizörlerin hazırlanmasında emdirme sırasının katalizör içindeki metallerin indirgenmelerini ve dolayısıyla katalitik performanslarını önemli ölçüde etkilediği gösterilmiştir. Önce Ni sonra Co yüklenerek hazırlanan katalizörde kobaltın daha fazla indirgenmiş olduğu ve dolayısıyla Co@Ni@SGA katalizörünün daha kararlı ve yüksek aktivite gösterdiği bulunmuştur. Bimetalik Ni-Co katalizörler metanın kuru reformlanma reaksiyonuna yüksek aktivite gösterirken, karbon oluşumuna da yüksek direnç göstermişlerdir. Metanın kuru reformlanma reaksiyonunda yüksek aktivite gösteren Co@Ni@SGA katalizörünün üzerinde biriken karbon miktarı (kütlece %3,6), Ni@Co@SGA katalizörüne (kütlece %2,1) göre daha yüksektir. Elde edilen ürün dağılımındaki H2/CO oranı 0,78 olarak belirlenmiştir.

In this article, a selective and sensitive spectrophotometric by chelating with 2,3,4,6/-tetrahydroxy-3/-sulfoazobenzene (THSA) at pH 5.5 (5-6) without applying any preconcentration process for nickel determination method is proposed. A selective and sensitive spectrophotometric method has been proposed for the determination of nickel by forming chelate at pH 5.5 (5-6) with 2,3,4,6/- tetrahydroxy-3/-sulfoazobenzene (THSA). Molar absorptivity of the complex having metal ligand ratio of 1:1 is 1.60 × 104 L mol-1 cm-1 at 485 nm. The complex compound is stable for 3 hours. Furthermore, it is stable up to 50 ° C. The developed method obeys Beer's law for 0.040-2.348 µg mL-1 Ni(II). Earth alkaline elements, alkaline elements, rare earth elements, halides, phosphates, ascorbic acid and cations do not interfere nickel determination. The proposed method is rapid and simple, and it can be easily applied on certificated alloys and environmental water samples for determining nickel. [ABSTRACT FROM AUTHOR]

Background and Design: Allergic contact dermatitis is a delayed (type 4) reaction against external contact agents. It occurs within 48-96 hours after re-contact of allergen with pre-sensitized skin. Materials and Methods: There are many allergens on earth that are not in protein structure. Paints, oils, resins, chemicals used in the textile industry, rubber, cosmetics, insecticides, plants, bacteria, fungi and parasites can cause allergic contact dermatitis. Patch test is the gold standard for diagnosis and provides valuable results when evaluated according to history and physical examination findings. In this study, we evaluated the patch test results of 673 patients. Results: The most common allergens in our study were nickel sulfate (18.3%), cobalt chloride (5.1%), potassium dichromate (4.8%), thiuram mix (4.3%), p-phenylenediamine (3.7%) and formaldehyde (2.5%). Conclusion: In order to obtain more and more accurate information about the most common contact allergens in our country, we believe that there is a need for studies in different centers and at different time intervals. This is why we want share this study that we conducted in Ankara/Turkey. [ABSTRACT FROM AUTHOR]

The objectives of this study were to determine effects of different priming treatments on germination and seedling growth in red fescue infected with different levels (0, 75, 150 and 300 mg l-1) of cadmium and nickel. The study was conducted under laboratory conditions. In the study, two heavy metal kinds (Cadmium (Cd) and Nickel (Ni)) were considered 3 different concentrations (75, 150, 300 mg l-1) and distillate water as control application. To determine the effect of germination priming under heavy metal stress, 2% KNO3 and 500 ppm GA3 were used as priming agents. The research was performed as factorial arrangement of completely randomized design with four replications. The results of study indicated that both germination and seedling growth properties were negatively affected by both heavy metal kinds. Priming treatments were ineffective in reducing the effects of heavy metals on germination properties. Germination at high doses of heavy metals was negatively affected by priming treatments. There wasn't positively effect on root length of red fescue of priming treatments, while shoot length was positively affected by GA3 treatment. Also, the negatively effects on germination and seedling growth of nickel were greater than cadmium. [ABSTRACT FROM AUTHOR]