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We consider the effect that an upstream cylinder has on the effective inertial collection efficiency of a downstream cylinder. We consider an initially uniform distribution of particles moving past a cylindrical fiber in a potential crossflow and numerically calculate the resulting particle distribution far downstream of the fiber using finite differences. We then investigate the effect that the downstream distribution of particles has on the effective inertial collision efficiency of a downstream test cylinder oriented parallel to the first. We show that the effective collision efficiency of the test cylinder depends on its relative offset in the transverse direction (normal to the flow) with respect to the upstream cylinder. For relatively small offsets there is complete shielding, and no particles collide with the test cylinder. As the offset increases, a growing effective collision efficiency is observed leading to a significant enhancement relative to the collision efficiency of an isolated cylinder for intermediate offsets and Stokes numbers close to unity. Importantly, we observe relative gains in effective collision efficiency above 100% for a range of Stokes number and offset values. For larger offsets and Stokes numbers, the effect of the upstream cylinder on the effective collision efficiency of the test cylinder decreases and eventually becomes negligible. Detailed results are provided for Stokes drag acting on the particles and we also show that a non-linear drag has negligible effect on the observed trends for the conditions relevant to filtration systems. These results suggest that the arrangement of fibers has a substantial effect on inertial particle impaction even when neighboring fibers do not alter the flow field around each individual collector. Moreover, periodic arrangements with specific orientations with respect of the flow could lead to a significant enhancement of the inertial collision of particles on an array of collectors, thus contributing towards a better filtration performance.

Poly(ethylene oxide) (PEO)-based polymer electrolytes are a promising class of materials for use in lithium-ion batteries due to their high ionic conductivity and flexibility. In this study, the effects of polymer architecture including linear, star, and hyperbranched and salt (lithiumbis(trifluoromethanesulfonyl)imide (LiTFSI)) concentration on the glass transition (Tg), microstructure, phase diagram, free volume, and bulk viscosity, all of which play a significant role in determining the ionic conductivity of the electrolyte, have been systematically studied for PEO-based polymer electrolytes. The branching of PEO widens the liquid phase toward lower salt concentrations, suggesting decreased crystallization and improved ion coordination. At high salt loadings, ion clustering is common for all electrolytes, yet the cluster size and distribution appear to be strongly architecture-dependent. Also, the ionic conductivity is maximized at a salt concentration of [Li/EO ≈ 0.085] for all architectures, and the highly branched polymers displayed as much as three times higher ionic conductivity (with respect to the linear analogue) for the same total molar mass. The architecture-dependent ionic conductivity is attributed to the enhanced free volume measured by positron annihilation lifetime spectroscopy. Interestingly, despite the strong architecture dependence of ionic conductivity, the salt addition in the highly branched architectures results in accelerated yet similar monomeric friction coefficients for these polymers, offering significant potential toward decoupling of conductivity from segmental dynamics of polymer electrolytes, leading to outstanding battery performance.

© 2023 Wiley Periodicals LLC.In this study, we have synthesized a series of 3-(pyridin-2-yl)-2-(pyridin-2-ylimino)thiazolidin-4-ol derivatives regioselectively from 2-iminothiazolidin-4-ones using LiAlH4 at room temperature. Due to the presence of the restricted rotation around the N3-Caryl single bond, the formation of M/P isomers was observed. The OH group of the hemiaminal was found to orient itself on the same side with pyridyl nitrogen during this restricted rotation to form an intramolecular hydrogen bond, which was demonstrated by the computational DFT study. This orientation presumably inhibited the occurrence of dehydration and stabilized the molecule.

The combination of ethyl (hydroxyimino)cyanoacetate (Oxyma) and diisopropylcarbodiimide (DIC) has demonstrated superior performance in amino acid activation for peptide synthesis. However, it was recently reported that Oxyma and DIC could react to generate undesired hydrogen cyanide (HCN) at 20 °C, raising safety concerns for the practical use of this activation strategy. To help minimize the risks, there is a need for a comprehensive investigation of the mechanism and kinetics of the generation of HCN. Here we show the results of the first systematic computational study of the underpinning mechanism, including comparisons with experimental data. Two pathways for the decomposition of the Oxyma/DIC adduct are derived to account for the generation of HCN and its accompanying cyclic product. These two mechanisms differ in the electrophilic carbon atom attacked by the nucleophilic sp2-nitrogen in the cyclization step and in the cyclic product generated. On the basis of computed “observed” activation energies, ΔGobs⧧, the mechanism that proceeds via the attack of the sp2-nitrogen at the oxime carbon is identified as the most kinetically favorable one, a conclusion that is supported by closer agreement between predicted and experimental 13C NMR data. These results can provide a theoretical basis to develop a design strategy for suppressing HCN generation when using Oxyma/DIC for amino acid activation.

The treatment of boron(III) subphthalocyanine chloride (SubPcCl) with borondipyrromethene (BODIPY) derivative consisting one pyrene group in toluene gave the corresponding axially substituted boron(III) subphthalocyanine dyad (SubPcBodiPy). Novel compound has been fully characterized by FTIR, mass, NMR (1H and 13C) spectroscopy and elemental analysis. Photophysical properties of SubPcBodiPy was investigated and compared with its precursors by fluorescence and absorption spectroscopy in THF. Accordingly, fluorescence lifetimes were measured directly by single exponential calculation.

The aim of the study was to investigate decolourization of Methylene Blue (MB) in aqueous solution using advanced oxidation processes (AOPs) and biosorption comparatively. Photocatalytic decolourization of MB was studied using TiO2 as catalyst. The photocatalytic decolourization of MB by direct UV irradiation alone, only TiO2 and TiO2/UV processes was investigated. It was found that decolourization by photocatalytic process of MB increased with decreasing pH, and decolourization rate also increased in the presence of TiO2/UV when compared to UV irradiation alone. Decolourization of MB was also studied with using the Fenton process (Fe(II)/H2O2). Concentrations of Fe(II) and H2O2 on decolourization ratio were investigated. The optimum catalyst to H2O2 ratio was found 1:3 at pH 4.0. In the second part of the study, the biosorption process was conducted with using plant gall immobilised alumina. The removal percentages were calculated with both plant gall immobilised alumina and alumina alone. The immobilisation of plant gall increased the removal percentages from 60-70% to 90-95%. The proposed methods (AOPs and biosorption) have both advantages and disadvantages compared to each other.

This study aims to characterize the proximate composition, antioxidant activity, phytochemical profile, anti-diabetic, and anti-inflammatory properties of Juglans regia kernel meal (JKM). The examination of the proximate composition reveals that JKM contains moisture (7.74%), ash (4.46%), crude fat (31.26%), crude fiber (8.41%), crude protein (8.99%) and nitrogen-free extract (39.14%). The analysis of JKM for antioxidant properties shows lipid peroxidation inhibition (63.78%), ferric ion reducing antioxidant power (103.44 mg/g), 2,2-diphenyl-1-picrylhydrazyl hydrate (57.91%), and vitamin C (152.87 mg/g). The phytochemical compositional analysis shows that JKM has alkaloids (12.08 %), saponins (43.49 mg/g), steroids (4.84 mg/g), flavonoids (14.74 mg/g), tannins (1.69 mg/g) and phenol (35.93 mg/g). The JKM also demonstrated alpha-amylase inhibition and alpha-glucosidase inhibition activities of 61.06% and 67.76%, respectively; while 62.71% and 79.17% were reported for the albumin denaturation inhibition and antiproteinase activity of JKM, respectively. JKM dietary supplementation may enhance the animals' welfare. It is advised to employ it in an animal model, though.

Bu çalışmada, Gd3+ iyonlarının tayini için, katyonik yüzey aktif madde olan heksadesiltrimetilamonyum bromür (HDAB) ve ksilen turuncusu indikatörünün kullanılabilirliği incelenmiştir. Geliştirilen metot için yüksek pH değerlerinde Gd3+ içeren sulu çözeltiye ksilen turuncusu ve HDAB ilave edilerek oluşan kompleksin absorbans değerleri spektrofotometre cihazı ile 250-750 nm aralığında okunmuştur. 580 nm de ksilen turuncusu-Gd3+ kompleksi için elde edilen absorbans değerlerinin, ortama HDAB ilavesinden sonra 624 nm’ye kaydığı gözlemlenmiştir. Optimize şartlarda geliştirilen metodun, gadolinyum için tayin sınırı 120 µg L-1, bağıl standart sapma %1,1 ve kalibrasyon aralığı ise 150-800 µg L-1 olarak bulunmuştur. Metodun doğruluğu ise gerçek su numunelerine ekleme/geri kazanım testleriyle belirlenmiştir. %84-96 geri kazanım değerleriyle, geliştirilen metodun içme, dere ve hastane atık suyu numunelerinde gadolinyum tayini için uygulanabileceği görülmüştür., In this study, the usability of the cationic surfactant hexadecyltrimethylammonium bromide (HDAB) and xylene orange indicator were investigated for the determination of Gd3+ ions. For the developed method, xylene orange and HDAB were added to the aqueous solution containing Gd3+ at high pH values, and the absorbance values of the complex formed with the spectrophotometer instrument were recorded in the range of 250-750 nm. It was observed that the absorbance values obtained for the xylene orange-Gd3+ complex at 580 nm shifted to 624 nm after HDAB addition to the medium. The detection limit for gadolinium was 120 µg L-1, the relative standard deviation was 1.1%, and the calibration interval was 150-800 µg L-1 for the method developed under optimized conditions. The accuracy of the method was determined by adding/recovering tests to real water samples. It has been observed that the developed method can be applied for the determination of gadolinium in drinking, stream, and hospital waste water samples, with recovery values of 84-96%.

Entamoeba histolytica is one of the common causes of infection in humans around the world. It causes clinically significant infection due to the fact that it causes morbidity and mortality. There is a need for new and safe drugs in the treatment of amebiasis. In this study, the activity of proton pump inhibitors against this parasite were investigated. Pantoprazole, lansoprazole, omeprazole, esomeprazole and rabeprazole were examined in detail. Initially, related drugs are optimized at M062X/6-31+G(d) level in water. Then, 3JS5, 3IDO and 3ILY were minimized at OPLS3e method. The docking calculations were performed and it is found that pantoprazole could be a significant candidate in the inhibiting of Entamoeba histolytica. Then, the interaction between pantoprazole and the target parasite were examined in the range of 0 – 100 nanoseconds (ns). The interaction energies in each one ns were calculated. As a result, the interaction was found as stronger than 88 ns. Pantoprazole was clinged to Entamoeba histolytica to inhibiting it.

Fibrous materials from polylactic acid (PLA) and polyvinylpyrrolidone (PVP) containing mandarin peel essential oil (MPEO) and/or nano-calcium carbonate were prepared by electrospinning process. The electrospun webs were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and microbiological tests. IR spectra results indicated the existence of interaction among additives and polymer matrix. Obtained SEM results showed that incorporation of essential oil to the polymer matrix have a remarkable effect on the fiber morphology. Essential oil incorporation increased the fiber diameters. The electrospun composite webs were ineffective against Acinetobacter baumannii, Bacillus subtilis, Escherichia coli, Enterococcus fecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus.

The Mentha pulegium, Lepidiıum draba and Centaurea solstitialis have traditionally been used in different cultures for the treatment of various diseases. We investigated the total phenolic content analysis, chemical compositions and antioxidant activities of different solvent extracts such as acetone, methanol and n-hexane obtained from the aerial parts of Mentha pulegium, Lepidiıum draba and Centaurea. The amount of total phenolic substance was determined as gallic acid equivalent determine. Also, the LC-MS/MS technique was used to determine the phenolic profiles of each extract. Finally, antioxidant activities of three extracts were determined by DPPH and ABTS methods. The highest total phenolic content for acetone, n-hexane and methanol extracts was found as 99 507, 46 305, and 18 227 μg GAE mL-1 in Centaurea solstitialis plant, respectively. While the major component rosmarinic acid amount in the acetone extract of Mentha pulegium was 128 195 μg analyte g-1 extract, this amount was determined as 780 383 μg analyte g-1 extract in the methanolic extract. The highest DPPH radical scavenging activity was found in the acetone and methanolic extracts of Mentha pulegium as 77% and 79%, respectively. ABTS radical scavenging activity was also found to be 98% and 94% for Mentha pulegium in acetone and methanol extracts, respectively. The antioxidant capacity of the extracts is related to the total amount of phenolic substances.

İş sağlığı ve güvenliği kapsamında, okullarda çalışanların ve öğrencilerin maruz kaldıkları ve insan sağlığı üzerinde etkisi olduğu düşünülen uçucu organik bileşiklerin ölçümü yapılmıştır. Bu çalışmanın değerlendirilmesinde ilgili mevzuat ve standartlarda belirlenen sınır değerleri referans alınmıştır. Çalışma kapsamında elde edilen numuneler Gaz kromatografisi-kütle spektrometresi (GC/MS) ile ölçüme tabii tutulmuştur. Ölçüm için Iğdır ili ve çevresinde belirlenen 10 okulda pasif hava örnekleme izleme cihazı 12 günlük bir zaman dilimi için bırakılmıştır. Elde edilen bulgulara göre toluen (6.8 µppm), aseton (5.4 µppm) ve etanol (39.5 µppm) değerleri okulların koordinatlarına göre farklılık göstererek diğer bileşiklere kıyasla yüksek bulunmuştur. Bu değerler kabul edilebilir referans aralıklarında olup, daha hassas cihaz ve yöntemlerle ileri ölçümler önerilmektedir., Within the scope of occupational health and safety, measurements of volatile organic compounds, which are thought to have an impact on human health and to which employees and students are exposed, were measured. In the evaluation of this study, the limit values determined in the relevant legislation and standards were taken as reference. The samples obtained within the scope of the study were subjected to measurement by Gas chromatography-mass spectrometry (GC/MS). For measurement, a passive air sampling monitoring device was left in 10 schools selected in and around Iğdır province for a period of 12 days. According to the findings, toluene (6.8 µppm), acetone (5.4 µppm) and ethanol (39.5 µppm) values differed according to the coordinates of the schools and were found to be higher compared to other compounds. These values are within acceptable reference ranges, and further measurements with more sensitive instruments and methods are recommended.

Dimethyl carbonate (DMC) is a green solvent and an environmentally friendly fuel additive. It is produced by carbonylation of methanol The production cost of DMC is very high by conventional processes because DMC and methanol form azeotrope and cannot be separated by distillation. Its separation can be performed by pervaporation (PV) economically. Pervaporation (PV) is also an environmentally friendly membrane process in which liquid-liquid mixtures are separated under vacuum with high selectivity. Pervaporation selectivity is dependent on sorption selectivity and diffusion selectivity. Membrane used in the pervaporation process is a semi-permeable barrier and provides selective separation and transport. In PV development of an appropriate membrane material is important for obtaining pure substances. Hydrophilic membrane can separate methanol which is a polar component. Chitosan is a harmless, biodegradable, natural polymer and, despite having hydrophilic properties, cannot withstand aqueous conditions. Therefore, it should be modified by crosslinking. Tetraethoxysilan (TEOS) and tungstophosphoric acid (TPA) can be used as crosslinking agents and additive blending components in membrane production for increasing chemical and mechanical stability. In this study, sorption tests were carried out to determine the usability of chitosan-tetraethoxysilan (TEOS) and chitosan-Tungstophosphoric acid (TPA) hybrid membranes in separation of DMC-Methanol mixture with PV.

Bu çalışmada protein esaslı nanolifler, özellikleri ve uygulama alanları araştırılmış ve yumurta akı proteininden nanolifli yüzey üretimi gerçekleştirilmiştir. Proteinler, bitkisel ve hayvansal olmak üzere iki ana gruba ayrılırlar. Biyolojik yapıdaki bu proteinler, medikal alan başta olmak üzere gıda endüstrisinde ve kozmetik sanayiinde çeşitli kullanım alanlarına sahiptir. Bu araştırmada, protein esaslı polimerler alt sınıflara ayrılmış, her birinin özellikleri verilmiş, nanolif üretimlerinden bahsedilmiş ve protein esaslı nanoliflerin kullanım alanlarına değinilmiştir. Ayrıca yumurta akı proteini kullanılarak elektro lif çekim teknolojisi ile nanolifli yüzeyler elde edilmiştir. Protein esaslı nanoliflerin biyomedikal alanda genel olarak, ilaç salım sistemleri ve doku mühendisliğinde yapı iskelesi, yara örtüsü, doku jenerasyonu gibi alanlarda kullanımı söz konusudur. Medikal alan dışında ise biyolojik yapısından kaynaklı gıda endüstrisinde de paketleme malzemesi olarak kullanımı söz konusudur. Ayrıca, protein esaslı nanoliflerin filtre malzemesi, biyosensör, katalizör, deri protezleri, ameliyat iplikleri, yumuşak kontakt lensler gibi çok çeşitli kullanım alanları da mevcuttur., In this study, protein-based nanofibers, their properties and application areas were investigated and nanofiber surface production was carried out with egg white protein. Proteins are divided into two main groups, vegetable and animal. These biological proteins have various uses in the food industry, cosmetics industry and especially in the medical field. In this research, protein-based polymers are subclassified according to their source. The general properties of these proteins and the usage areas of protein-based nanofibers are mentioned. In addition, nanofiber surfaces were obtained with electrospinning technology using egg white protein. The protein-based nanofibers are generally used in the field of biomedicine, drug delivery systems and tissue engineering in areas such as scaffolding, wound dressing, tissue generation. Apart from the medical field, it is also used as a packaging material in the food industry due to its biological structure. In addition, protein-based nanofibers have a wide range of uses such as filter material, biosensors, catalysts, skin prostheses, surgical threads, soft contact lenses and etc.

The ink industry is one of the world\"s largest markets due to the increasing demand for printing inks for the packaging industry. Flexography printing is a well-known promising technology for large-area printing due to its high printing speed and roll-to-roll capability to print economically on a variety of surfaces and is used in nearly in all areas of packaging printing. Water-based inks are considered non-toxic, odourless, and more environmentally friendly options compared to solvent-based inks. Therefore, in this article, the goal was to develop new water-based ink formulation with different acrylic binders for flexographic printing on commercial solid bleached sulphate (SBS) board. Five inks were formulated with four different acrylic binders and compared to a commercially available ink to study their performance. The developed inks were investigated with regard to their print qualities and print characteristics. It was found that the binder type influenced some print quality while the effect was not significant for others. Using flexography printed cyan inks, the ink formulated with the highest molecular weight had the lowest print density and the largest tonal value increase (TVI) observed between 40 and 60 tone values. The same ink had the largest mottle values and variation in topography. For values of print contrast and delta gloss at 75 degrees, although differences were observed between average values, data had inconclusive variation and spread around averages, where no conclusive trends or effects of acrylic binder type on these response factors were observed. Print chroma and dot roundness results were equally close for all printed samples.

A saturation–capillary pressure relationship is proposed that is applicable for all wettabilities, including mixed-wet and oil-wet or hydrophobic media. This formulation is more flexible than existing correlations that only match water-wet data, while also allowing saturation to be written as a closed-form function of capillary pressure: we can determine capillary pressure explicitly from saturation, and vice versa. We propose $$P_{{\text{c}}} = A + B\tan \left( {\frac{\pi }{2} - \pi S_{e}^{C} } \right)\,{\text{for}}\,0 \le S_{{\text{e}}} \le 1,$$ P c = A + B tan π 2 - π S e C for 0 ≤ S e ≤ 1 , where $$S_{{\text{e}}}$$ S e is the normalized saturation. A indicates the wettability: $$A>0$$ A > 0 is a water-wet medium, $$A A < 0 is hydrophobic while small A suggests mixed wettability. B represents the average curvature and pore-size distribution which can be much lower in mixed-wet compared to water-wet media with the same pore structure if the menisci are approximately minimal surfaces. C is an exponent that controls the inflection point in the capillary pressure and the asymptotic behaviour near end points. We match the model accurately to 29 datasets in the literature for water-wet, mixed-wet and hydrophobic media, including rocks, soils, bead and sand packs and fibrous materials with over four orders of magnitude difference in permeability and porosities from 20% to nearly 90%. We apply Leverett J-function scaling to make the expression for capillary pressure dimensionless and discuss the behaviour of analytical solutions for spontaneous imbibition.

Packaging must have a good commercial appearance and is generally obtained by ink transferred to its substrate. It is important that the ink used in packaging printing is produced from environmentally friendly and sustainable raw materials as well as being suitable for the printing system. The increasing demand in the field of printed packaging and the scarcity of resources to meet this demand have accelerated the search for new sources for inks. For this purpose, inks produced in the laboratory using a modified cellulose-based binder, a commercial acrylic resin and a commercial soybean protein were compared with a commercial ink. As a result of the study, it was determined that the printability properties of the ink obtained by using the modified cellulose-based binder were better than the ink obtained with commercial soybean protein. It was determined that it showed printability properties close to the ink produced with commercial acrylic binders. By using modified cellulose-based water-based flexographic ink instead of other commonly used binders, more environmentally friendly sustainable inks can be produced.

Dünyada temel endüstrilerden biri olan kimya endüstrsinde katalitik reaksiyonlar kimyasal üretimin büyük kısmını oluşturur. Ayırma saflaştırma işlemlerinde sıkça kullanılan membran teknolojisi, katalizör teknolojisi ile birleştirilince, oluşan yeni hibrit yapılarla daha çevreci katalitik proseslere katkı sağlayabilir. Elde edilen hibrit yapıdaki katalitik membranlar kendi içlerinde reaksiyon ve ayırmayı beraber gerçekleştirirler. Böylece ek ayırma birimleri gerektirmezler. Reaksiyon sonucu yan ürünü tutarak veya geçirerek reaksiyon dönüşümünü arttırabilirler. Katalitik membranlar heterojen yapılı olduğu için reaksiyon karışımından geri kazanımları kolaydır. Etkinliklerinde çok az bir azalmayla tekrar kullanılabilirler. Kimya endüstrisinde sıkça rastlanan esterleşme reaksiyonlarında etil astetat, etil laktat, izopropil asetat üretiminde, transesterleşme reaksiyonlarında fosil yakıtlara çevreci bir alternatif olan biyodizel üretiminde, asetalizasyon reaksiyonlarında yakıt katkı maddesi ve parfümlerde kullanılan güzel kokuların üretiminde reaksiyonu katalizlemek ve dönüşümü arttırmak için kullanılırlar. Bu çalışmanın amacı katalitik membranlarla ilgili yapılacak çalışamalara ışık tutmaktır. Yapılan bu çalışmada üretimlerinden, kullanıldıkları reaksiyonlardan, katalitik reaksiyonlarda sağladıkları avantajlardan, kullanım koşullarından söz edilmiştir.

ispartof: JOURNAL OF PROCESS CONTROL vol:117 pages:169-180 status: published

In this study, microwave assisted ring opening of benzonorbornadiene epoxide with alcohols was investigated. New alkoxy alcohols were synthesized regioselectively by Wagner–Meerwein rearrangement in short reaction times (up to 10 minutes) with high yield in the presence of a cheap and environmentally friendly heterogeneous montmorillonite-K10 catalyst. The products were purified by filtration only., Bu çalışmada, benzonorbornadien epoksitinin alkollerle mikrodalga destekli halka açılma tepkimeleri incelendi. Ucuz ve çevreci heterojen montmorillonite-K10 katalizörü eşliğinde yüksek verim ile kısa reaksiyon süresinde (10 dakikaya kadar) Wagner–Meerwein düzenlenmesi ile regioseçici olarak yeni alkoksi alkoller sentezlendi. Ürünler sadece süzme ile saflaştırıldı.

The performance of the drilling fluid used is very important for a successful operation in drilling applications. Recently, developments in drilling mud technology have gained economic significance as well as developments in horizontal and deep-sea drilling, where expensive technologies are used.In this study, it is aimed to compare the effects of raw perlite and expanded perlite on water-based drilling mud. For this purpose, water-based drilling muds were prepared and raw perlite and expanded perlite was added to the prepared mud samples at different rates (0.1-5 % w.v-1). Rheological properties such as plastic viscosity, apparent viscosity, breaking point, gel strength values (10 seconds and 10 minutes) of the prepared drilling mud were determined by FANN viscometer. Filtration properties were studied using API Filter Press. All measurements were performed according to American PetroleumInstitute (API) standards.The rheological and filtration properties of drilling mud prepared by adding raw and expanded perlite separately were compared with additive-free drilling mud and then among themselves. It has been determined that raw perlite and expanded perlite contribute positively to the rheological properties and filtration loss values of water-based drilling mud. In addition, it has been observed that expanded perlite has a better effect than raw perlite., Sondaj uygulamalarında başarılı bir operasyon gerçekleştirmek için kullanılan sondaj akışkanının performansı oldukça önemlidir. Son zamanlarda özellikle pahalı teknolojilerin kullanıldığı yatay ve derin deniz sondajlarındaki gelişmelerin yanı sıra sondaj çamuru teknolojisindeki gelişmeler de ekonomik anlam kazanmıştır. Bu çalışmada, ham perlit ve genleştirilmiş perlitin su bazlı sondaj çamuruna etkisinin karşılaştırılması amaçlanmıştır. Bu amaçla, su bazlı sondaj çamurları hazırlanmış ve hazırlanan çamur numunelerine farklı oranlarda (0.1 - 5 % k.h-1) ham perlit ve genleştirilmiş perlit ikame edilmiştir. Hazırlanan sondaj çamurlarının plastik viskozitesi, görünür viskozitesi, kopma noktası, jel mukavemeti değerleri (10 saniye ve 10 dakika) gibi reolojik özellikleri FANN viskozimetresi, filtrasyon kaybı özellikleri de API Filter Press aracılığıyla tespit edilmiştir. Tüm ölçümler Amerikan Petrol Enstitüsü (API) standartlarınauygun bir şekilde gerçekleştirilmiştir.Ham ve genleştirilmiş perlitin ayrı ayrı eklenmesi ile hazırlanan sondaj çamurlarının reolojik ve filtrasyon özellikleri ilk olarak katkısız sondaj çamuruyla daha sonra da kendi içlerinde karşılaştırılmıştır. Ham perlit ve genleştirilmiş perlitin su bazlı sondaj çamurunun reolojik özellikleri ile filtrasyon kaybı değerlerine olumlu yönde katkı sağladığı tespit edilmiştir. Ayrıca genleştirilmiş perlitin, ham perlite oranla daha iyi bir etkiye sahip olduğu görülmüştür.

In this study, firstly, monoimine compound (H3A) was synthesized from the condensation of 2-aminobenzylamine and 1’-hydroxy-2-acetonaphthone which is a ketone derivative. Asymmetric Schiff base (H2L) was synthesized as a result of the condensation of the obtained H3A and 5-bromosalicylaldehyde. After that, the synthesis and characterization of the Cu(II), Ni(II), Co(II) and Fe(III) complexes of the synthesized H2L compound were carried out. The proposed structures of Schiff bases and its metal complexes were elucidated using analytical and spectroscopic (UV-Vis, FT-IR, elemental, 13C and 1H NMR, LC-MS, ICP-AES, magnetic susceptibility, molar conductivity, and TG-DTA) methods., Bu çalışmada önce 2-aminobenzilamin ile keton türevi olan 1'-hidroksi-2'-asetonaftonun kondenzasyonundan monoimin bileşiği (H3A) sentezlenmiştir. Elde edilen H3A ile 5-bromosalisilaldehitin kondenzasyonu sonucu asimetrik Schiff bazı (H2L) sentezlenmiştir. Daha sonra sentezlenen H2L bileşiğinin Cu(II), Ni(II), Co(II) ve Fe(III) komplekslerinin sentezi ve karakterizasyonu gerçekleştirilmiştir. Schiff bazı ve metal komplekslerinin yapıları analitik ve spektroskopik yöntemler (UV-Vis, FT-IR, elementel, 13C ve 1H NMR, LC-MS, ICP-AES, manyetik suseptibilite, molar iletkenlik ve TG-DTA) kullanılarak aydınlatılmıştır

Inhibition of the angiotensin-converting enzyme (ACE, EC 3.4.15.1) is one of the most important hypertension treatments. Here, ACE was purified from human plasma with affinity chromatography. The purity and molecule weight of ACE were identified utilizing the SDS-PAGE and viewed in two bands at around 60 kDa and 70 kDa on the gel. KM and Vmax constants from the Lineweaver-Burk graphic were computed to be 0.6 mM and 175.44 (µmol/min).mL-1 , respectively. The effects of folic acid (vitamin B9) on purified ACE were studied. Folic acid on purified ACE demonstrated an inhibitory efficacy. The IC50 value for folic acid was calculated to be 127.94 µM. Kind of inhibitory and Ki constant for folic acid were defined. The kind of inhibitory for folic acid was found as non-competitive inhibitory. Ki constant was computed to be 226.59 µM for folic acid. In this study, it was concluded that folic acid, which shows an inhibitor efficacy on ACE, may have both therapeutic and protective impacts against hypertension.

The reaction medium plays a key role in organic synthesis and pharmaceutical research. There are many opinions on choosing the best condition, including cost and environmental implications, but the main requirement is that they have the necessary interaction with solvents to cause dissolution, precipitation, stabilization, or instability. For this purpose, in this article synthesis of the thiazole ring was made under various reaction conditions. So new compounds 2-(isoquinolin-5-ylimino)-3-phenylthiazolidin-4-one (1), (4-amino-3-phenylthiazol-2(3H)-ylidene) isoquinolin-5-amine (2), (4-amino-3-phenylthiazol-2(3H)-ylidene) isoquinolin-5-amine (3) were synthesized from the reaction between thiourea derivative and monochloroacetic acid, diethyloxalate and chloro acetonitrile. For this synthesizes were created in various reaction conditions, using different bases (sodium acetate/sodyum etoksit/ triethylamine or pyridine) and solvents (1,4-dioxane, toluene, acetic acid, ethanol, tetrahydrofuran, dimethyl formamide). At the end of these reactions, the best efficiency was obtained with the one-pot reaction using THF/DMF, Et3N. The structures of all novel compounds reported herein were established using FT-IR, 1H NMR, and 13C NMR spectra as well as elemental analysis technique.

The design of adsorption systems for separation of CO2/N2 in carbon capture applications is notoriously challenging because it requires constrained multiobjective optimization to determine appropriate combinations of a moderately large number of system operating parameters. The status quo in the literature is to use the nondominated sorting genetic algorithm II (NSGA-II) to solve the design problem. This approach requires 1000s of time-consuming process simulations to find the Pareto front of the problem, meaning it can take days of computational time to obtain a solution. As an alternative approach, we have employed a Bayesian optimization algorithm, the Thompson sampling efficient multiobjective optimization (TSEMO). For constrained productivity/energy usage optimization, we find that the TSEMO algorithm is able to find an essentially identical solution to the design problem as that found using NSGA-II, while requiring 14 times less computational time. We have used the TSEMO algorithm to design a postcombustion carbon capture system for a 1000 MW coal fired power plant using two adsorbent materials, zeolite 13X and ZIF-36-FRL. Although ZIF-36-FRL showed promising process-scale performance in previous studies, we find that the industrial-scale performance is inferior to the benchmark zeolite 13X, requiring a 21% greater cost per tonne of CO2 captured. Finally, we have also tested the performance of the Bayesian design framework when coupled with a data-driven machine learning process modeling framework. In this instance, we find that the incumbent NSGA-II offers better computational performance than the Bayesian approach by a factor of 3.

The phosphorous acid salts are widely used in the industry because of the effective treatment against various fungal diseases encountered in plants. The production process is exothermic and, with high temperatures around 94℃ achieved, significant risks were observed in terms of occupational health and safety. Therefore, the aim is to design a control system that will make this production process reliable for human health, economic and ecological damage. For this purpose, studies were carried out to determine the optimum operating mode, heat transfer system, and temperature controller design to prevent a sudden temperature rise. First, the overall heat transfer coefficient between the reactor and the jacket was determined as 51.0930 W/m2℃ and, the refrigerant was chosen as cooling water with 1.271 g/s flow rate which is relatively more economical and accessible. The model parameters of the system were determined with a detailed dynamic analysis by giving positive and negative step inputs to the cooling water flow rate and then obtaining model parameters through reaction curve and linear regression methods. By using the obtained model parameters theoretical P, PI and PID parameters were calculated by Cohen Coon and, Ziegler-Nichols approaches, and the success of controller parameters was tested, simulated with the MATLAB Simulink program and lastly, successful temperature control was achieved in the experimental system.

We report the results of modelling the transport of n-octane and n-hexadecane and their mixtures through carbonaceous nanopores at high-pressure conditions. Pores are modelled as smooth slit sheets with perturbations added as ridges and steps and a version of the Statistical Associating Fluid Theory (SAFT-γ Mie) is used both as equation of state and as a coarse-grained force field to account for fluid-fluid and fluid-solid molecular interactions. Molecular simulation allowed the description of transport diffusivities in terms of molecular flow, using boundary driven non-equilibrium molecular dynamics (BD-NEMD). Transport diffusivities are also independently calculated using equilibrium and external force non-equilibrium molecular dynamics (EF-NEMD) simulations, after accounting for the adsorption on the pores. We show consistency between the approaches for quantifying transport in terms of permeabilities (Darcy flows) and transport diffusivities. We find that smooth slit carbon pore models, which are commonly employed in literature as surrogates for kerogen regions in shale, are an inadequate representation of ultra-confined natural pores. For slit pores, the flow patterns are characterized by a fully-mutualized plug-like flow and fast transport. However, by incorporating even a small amount of rugosity (roughness) to the solid walls, the diffusion coefficients decrease dramatically with surface roughness significantly affecting the characteristic transport and velocity profiles inside the pores. In all cases, it is seen that there are important cross-correlation effects, influencing the way components of the mixture flow together. Calculated self-diffusivities are orders of magnitude smaller than the observed transport diffusivities for liquid mixtures. This work has a direct impact on the understanding and modelling of unconventional hydrocarbon recovery and flow in organic shale rocks.

ispartof: CHEMICAL ENGINEERING RESEARCH & DESIGN vol:184 pages:127-136 status: published

ispartof: SEPARATION AND PURIFICATION REVIEWS vol:52 issue:3 pages:242-261 status: accepted

ispartof: INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH vol:62 issue:24 pages:9549-9562 status: published