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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.

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

Elevated humidity levels in medical, food, and pharmaceutical products may reduce the products’ shelf life, trigger bacterial growth, and even lead to complete spoilage. In this study, we report a humidity indicator that mechanically bends and rolls itself irreversibly upon exposure to high humidity conditions. The indicator is made of two food-grade polymer films with distinct ratios of a milk protein, casein, and a plasticizer, glycerol, that are physically attached to each other. Based on the thermogravimetric analysis and microstructural characterization, we hypothesize that the bending mechanism is a result of hygroscopic swelling and consequent counter diffusion of water and glycerol. Guided by this mechanism, we demonstrate that the rolling behavior, including response time and final curvature, can be tuned by the geometric dimensions of the indicator. As the proposed indicator is made of food-grade ingredients, it can be placed directly in contact with perishable products to report exposure to undesirable humidity inside the package, without the risk of contaminating the product or causing oral toxicity in case of accidental digestion, features that commercial inedible electronic and chemo-chromatic sensors cannot provide presently.

ispartof: SEPARATION AND PURIFICATION TECHNOLOGY vol:313 status: accepted

This review discusses the developments in CO separation techniques in the last few decades and the gaps in knowledge it leaves, as well as sources of CO, both traditional and emerging, which would benefit from improved CO separation.

Following the initial cation formation, the synthesis of ionic liquids (ILs) often involves an anion-exchange or metathesis reaction. For hydrophobic ILs, this is generally performed through several cross-current contacts of the IL with a fresh salt solution of the desired anion. However, if a large number of contacts is required to attain an adequate conversion, this procedure is not economical because of the large excess of the reagent that is consumed. In this study, the metathesis of an IL, Aliquat 336 or [A336][Cl], to ILs with other anions ([A336][X] with X = HSO4–, Br–, NO3–, I–, and SCN–) was studied in a continuous counter-current mixer-settler setup. McCabe–Thiele diagrams were constructed to estimate the required number of stages for quantitative conversion. Significantly higher IL conversions were achieved, combined with reduced reagent consumption and waste production. This improvement in efficiency was most pronounced for anions placed low in the Hofmeister series, for example, HSO4–, Br–, and NO3–, which are difficult to exchange. The performance of the counter-current experiments was compared with the conventional multistep cross-current batch process by calculating the reaction mass efficiency (RME) and the environmental factor (E-factor). The RMEs of the cross-current experiments were notably smaller, that is, 38–78% of the values observed for the counter-current experiments. The E-factors of the counter-current experiments were a factor of 2.0–6.8 smaller than those of the cross-current experiments. These sustainability metrics indicate a highly efficient reagent use and a considerable, simultaneous decrease in waste production for the counter-current IL metathesis reactions., A counter-current flow diagram facilitates the efficient metathesis of ionic liquids and allows for a high conversion with minimal reagent consumption.

Yapılan bu çalışmada, ısıl ve kimyasal kararlılığı yüksek, biyo-uyumlu, ucuz ve toksik olmayan özellikleri ile pek çok uygulama alanında kullanılan çinko oksit (ZnO) nano-çiçekler; gözenekli karbon altlık olarak sürdürülebilir bir kaynak olan biyokütleden üretilen biyo-char üzerinde biriktirilmiştir. Biyokütle kaynağı olarak pirinç kabuğu seçilmiştir. Karbonizasyon süreci öncesinde ve sonrasında yapılan karakterizasyon çalışmalarının sonuçları çalışma içerisinde sunulmuştur. Pirinç kabuğunun sahip olduğu düşük nem miktarı (kütlece %2,01) ve yüksek uçucu madde miktarı (kütlece %63,48), bu hammaddenin karbonizasyon metodu ile gözenekli karbon malzeme üretimi için uygun olduğunu göstermektedir. Sentezlenen karbonlu malzemenin yüzey alanının 79,627 g/m2 ve gözenek boyutunun ise 5,07 nm olduğu görülmüştür. ZnO ince filmler, karbon altlık üzerine kimyasal banyo depolama tekniği kullanılarak biriktirilmiştir. Taramalı elektron mikroskobu (SEM) ve X-ışını difraktometresi (XRD) ile karakterize edilen ZnO nano-çiçeklerin kristal yapıya sahip olduğu belirlenmiştir ve tüm ince filmlerin yüzey morfolojileri ise homojen ve kompakttır., In this study, zinc oxide (ZnO) nano-particles that is used in many application areas with high thermal and chemical stability, biocompatible, cheap and non-toxic properties; was deposited onto the porous carbon on bio-char produced from biomass. Rice husk was chosen as the biomass source. The results of the characterization studies applied before and after the carbonization process were presented in the study. Rice husk is a suitable raw material for the production of porous carbon material by carbonization method with its low moisture content (2.01 wt.%) and high volatile matter content (63.48 wt.%). It was observed that the surface area of the synthesized carbonaceous material was 79.63 m2/g and the average pore size was 5.07 nm. ZnO nano-particles were deposited on the carbon substrate using chemical bath storage technique. ZnO nano-particles characterized by scanning electron microscopy (SEM) and X-ray diffractometry (XRD). It was determined that they have crystalline structure and the surface morphology of all thin films are homogeneous and compact.

Fosforoz asit ve potasyum hidroksitin ekzotermik nötralleşmesi tepkimesi sonucu oluşan monopotasyum fosfit ve dipotasyum fosfit tuzlarının üretiminde kullanılacak reaktör sistemin geliştirilmesi için tepkimeye ilişkin bilinmeyen unsurların saptanması, tepkimenin gerçekleştirileceği reaktörün ve işletim türünün, stokiyometrik oranın tespiti gerçekleştirilmiştir. Reaksiyon kinetiğinin bulunması için farklı derişim oranlarında fosforoz asit ve potasyum hidroksit çözeltileri hazırlanarak deneyler yapılmıştır. Tepkimeyle açığa çıkan ısının işletim türüyle ilişkisini incelemek için deneyler yarı-kesikli, kesikli ve sürekli işletim türlerinde gerçekleştirilmiştir. Ekzotermik reaksiyon sonucu oluşabilecek patlama, sıçrama gibi durumların etkisini gözlemleyebilmek, ürün spesifikasyonlarını değerlendirmek için deneyler asit üzerine baz ve baz üzerine asit beslemesi şeklinde gerçekleştirilmiştir. İki deney setinde de bir farklılık olmadığı saptanmıştır. Aynı zamanda yapılan deneyler sonucunda tepkime stokiyometrisinin 1:1.5 (asit:baz) molarite oranında gerçekleştirilmesi gerektiği ortaya konulmuştur. Yarı-kesikli reaktör sistemi yerine borusal bir reaktör sisteminde girdilerin reaktör boyunca belirli aralıklarla beslenmesini ve böylece ani patlama, sıçrama, sıcaklık yükselmesi ve reaksiyon hızının önüne geçilmesini sağlayacak aynı zamanda da bu besleme yöntemiyle ürün verimliliğini artırmayı amaçlayan bir borusal reaktör tasarlanmıştır. Deney sonucunda istenilen pH değeri olan 6.5 civarına ulaşılmış, reaktör içerisindeki sıcaklık kontrol edilebilmiş, istenen derişimlerde potasyum ve fosfor içeren ürün elde edilmiştir., In order to develop the system to be used in the production of monopotassium phosphite and dipotassium phosphite salts formed as a result of the exothermic neutralization reaction of phosphorous acid and potassium hydroxide, the unknown elements of the reaction were determined, the type of operation in which the reaction will be carried out, and the stoichiometric ratio were determined. To find the reaction kinetics, phosphorous acid and potassium hydroxide solutions were prepared in different concentrations and experiments were carried out. Experiments were carried out in semi-batch and batch and continuous operating modes to investigate the relationship between the heat released by the reaction and the operating modes. In order to observe the effect of explosion and splash that may occur as a result of exothermic reaction, and to evaluate product specifications, experiments were carried out both feeding acid on base and feeding base on acid. It was found that there was no difference between the two experimental sets. Also, it was shown that the reaction stoichiometry should be carried out in a 1: 1.5 (acid: base) molarity ratio, Instead of a semi-batch reactor system, a tubular reactor has been designed in a tubular reactor system that will ensure that the reactants are fed at certain intervals throughout the reactor, thus preventing sudden explosion, splashing, temperature rise and reaction speed, and at the same time increasing the product efficiency with this feeding method. As a conclusion the desired pH value of 6.5 was reached, the temperature in the reactor was controlled, and the product containing potassium and phosphorus at the desired concentrations was obtained.

This paper summarizes the submissions to a recently announced contact-mechanics modeling challenge. The task was to solve a typical, albeit mathematically fully defined problem on the adhesion between nominally flat surfaces. The surface topography of the rough, rigid substrate, the elastic properties of the indenter, as well as the short-range adhesion between indenter and substrate, were specified so that diverse quantities of interest, e.g., the distribution of interfacial stresses at a given load or the mean gap as a function of load, could be computed and compared to a reference solution. Many different solution strategies were pursued, ranging from traditional asperity-based models via Persson theory and brute-force computational approaches, to real-laboratory experiments and all-atom molecular dynamics simulations of a model, in which the original assignment was scaled down to the atomistic scale. While each submission contained satisfying answers for at least a subset of the posed questions, efficiency, versatility, and accuracy differed between methods, the more precise methods being, in general, computationally more complex. The aim of this paper is to provide both theorists and experimentalists with benchmarks to decide which method is the most appropriate for a particular application and to gauge the errors associated with each one.

In this paper, the no-wait flow shop problem with earliness and tardiness objectives is considered. The problem is proven to be NP-hard. Recent no-wait flow shop problem studies focused on familiar objectives, such as makespan, total flow time, and total completion time. However, the problem has limited studies with solution approaches covering the concomitant use of earliness and tardiness objectives. A novel methodology for the parallel simulated annealing algorithm is proposed to solve this problem in order to overcome the runtime drawback of classical simulated annealing and enhance its robustness. The well-known flow shop problem datasets in the literature are utilized for benchmarking the proposed algorithm, along with the classical simulated annealing, variants of tabu search, and particle swarm optimization algorithms. Statistical analyses were performed to compare the runtime and robustness of the algorithms. The results revealed the enhancement of the classical simulated annealing algorithm in terms of time consumption and solution robustness via parallelization. It is also concluded that the proposed algorithm could outperform the benchmark metaheuristics even when run in parallel. The proposed algorithm has a generic structure that can be easily adapted to many combinatorial optimization problems.

Hierarchical cation-exchange membranes (hCEMs) fabricated by blade coating and UV crosslinking of ionomer on top of a porous substrate demonstrated promising results in performing NaCl demineralization. In the food industry, complex solutions are used and hCEMs were never investigated before for these food applications. The performances of two different coating chemistries (urethane acrylate based: UL, and acrylic acid based: EbS) and three crosslinking degrees (UL5, UL6, UL7 for UL formulations, and EbS-1, EbS-2, EbS-3 for EbS formulations) were formulated. The impacts of hCEMs properties and crosslinking density on whey demineralization performances by electrodialysis (ED) were evaluated and compared to CMX, a high performing CEM for whey demineralization by ED. The crosslinking density had an impact on the hCEMs area specific resistance, and on the ionic conductance for EbS membrane. However, 70% demineralization of 18% whey solution was reached for the first time for hCEMs without any fouling observed, and with comparable performances to the CMX benchmark. Although some properties were impacted by the crosslinking density, the global performances in ED (limiting current, demineralization duration, global system resistance, energy consumption, current efficiency) for EbS and UL6 membranes were similar to the CMX benchmark. These promising results suggest the possible application of these hCEMs (UL6, EbS-2, and EbS-3) for whey demineralization by ED and more generally complex products as an alternative in the food industry.

The nuclear envelope (NE) is a double-membrane system surrounding the nucleus of eukaryotic cells. A large number of proteins are localized in the NE, performing a wide variety of functions, from the bidirectional exchange of molecules between the cytoplasm and the nucleus to chromatin tethering, genome organization, regulation of signaling cascades, and many others. Despite its importance, several aspects of the NE, including its protein-protein interactions, remain understudied. In this work, we present NucEnvDB, a publicly available database of NE proteins and their interactions. Each database entry contains useful annotation including a description of its position in the NE, its interactions with other proteins, and cross-references to major biological repositories. In addition, the database provides users with a number of visualization and analysis tools, including the ability to construct and visualize protein-protein interaction networks and perform functional enrichment analysis for clusters of NE proteins and their interaction partners. The capabilities of NucEnvDB and its analysis tools are showcased by two informative case studies, exploring protein-protein interactions in Hutchinson-Gilford progeria and during SARS-CoV-2 infection at the level of the nuclear envelope. ispartof: MEMBRANES vol:13 issue:1 ispartof: location:Switzerland status: published

The styrene oxide to styrene carbonate conversion performed in CO2 atmosphere, herein selected as a case study, was implemented in microdroplets (aerosol) reactions at the preparative scale (3.5 mmol of the starting material) and mild conditions (1 atm CO2 pressure), within a custom-made ultrasonic nebulization reactor. Upon opti-mization of the promoter stoichiometry (1 eq of 4.3 TEG/KI ratio) and methanol (MeOH) dilution (7.5 mL of 2.5 v/v MeOH/TEG), performances under mass transfer-limited conditions of this novel methodological paradigm have been compared at 25 degrees C and 50 degrees C with those implemented as: a) no-stirred, b) stirred, and c) sonicated bulk reactions. Complete selectivity and an apparent acceleration factor (AAF) of 1.9 was registered at both temperature for microdroplets reactions in respect with the sonicated counterparts, these latter performing better than the other bulk reactions. These significative efficiency improvements, candidate aerosol reactions as a preferred process intensification approach in the realm of effective CO2-utilization strategies and, in general, in the development and exploitation of gas-liquid two-phase reactions. The present work was supported by the NATO Science for Peace and Security Programme (NATO SPS, Grant No. MYP G5885, project acronym: TANGO). The authors are grateful to the funding agency.

The quest for sustainable monomers and \"green\" synthetic pathways for the design, fabrication, and modification of various polymers is of great importance and attracts a great deal of attention. Here, a highly versatile and novel bio-based platform was developed by reacting castor oil with propiolic acid for performing amino-yne click reactions. Owing to the electron-deficient nature of the propiolic acid esters, amino-yne click reactions were conducted with ease at room temperature, in the absence of any catalyst and solvent (as long as the amines were low-viscosity liquids at room temperature), and within 5 min. Several primary and secondary amines were shown to react readily with the developed platform. Furthermore, thermosets were prepared by using the propiolated castor oil and multifunctional amines. The prepared thermosets displayed improved thermal properties and elastomer-like mechanical properties.

The ease of functionalization of metal-organic frameworks (MOFs) can unlock unprecedented opportunities for gas adsorption and separation applications as the functional groups can impart favorable/unfavorable regions/interactions for the desired/undesired adsorbates. In this study, the effects of the presence of multiple functional groups in MOFs on their CF4/CH4, CH4/H-2, CH4/N-2, and N-2/H-2 separation performances were computationally investigated combining grand canonical Monte Carlo (GCMC) and molecular dynamics (MD) simulations. The most promising adsorbents showing the best combinations of selectivity, working capacity, and regenerability were identified for each gas separation. 15, 13, and 16 out of the top 20 MOFs identified for the CH4/H-2, CH4/N-2, and N-2/H-2 adsorption-based separation, respectively, were found to have -OCH3 groups as one of the functional groups. The biggest improvements in CF4/CH4, CH4/H-2, CH4/N-2, and N-2/H-2 selectivities were found to be induced by the presence of -OCH3-OCH3 groups in MOFs. For CH4/H-2 separation, MOFs with two and three functionalized linkers were the best adsorbent candidates while for N-2/H-2 separation, all the top 20 materials involve two functional groups. Membrane performances of the MOFs were also studied for CH4/H-2 and CH4/N-2 separation and the results showed that MOFs having -F-NH2 and -F-OCH3 functional groups present the highest separation performances considering both the membrane selectivity and permeability., European Research Council (ERC); European Union (EU); Horizon 2020; Research and innovation programme; ERC-2017-Starting Grant; COSMOS; Scientific and Technological Research Council (TÜBİTAK); ULAKBİM; High Performance and Grid Computing Center (TRUBA resources); National Center for High Performance Computing of Turkey (UHeM)

Corneal ulcer, which is brought on by a breach in the epithelial barrier, is a dangerous infection of the avascular corneal stroma. New treatment strategies are needed, suppressing the aggressive nature of the disease and including a combination of different drugs. In this study, vancomycin (VAN) and fluconazole (FLU) dual-drug loaded dual-layered polyvinyl alcohol and gelatin (PVA/GEL) nanofibrous patches are produced by electrospinning. Scanning electron microscopy (SEM) images show smooth surfaces are obtained for both pure and drug-loaded nanofibrous patches. The tensile test results report that loading the FLU and VAN separately into the PVA/GEL patches decrease both the tensile strength and elongation at break and it is further reduced when combining two drug-loaded layers in one patch. According to drug release results, the FLU and VAN-loaded nanofibrous patches show a controlled release profile extending up to 96 h. Moreover, PVA/GEL/FLU, PVA/GEL/VAN, and PVA/GEL/FLU/VAN nanofibrous patches display significant antimicrobial activity against Candida albicans and Staphylococcus aureus. SEM, 4\"-6diamidynofenyloindol (DAPI) staining, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay show that PVA/FLU and PVA/GEL/FLU/VAN nanofibrous patches have a superior effect on NIH3T3 cell spreading and proliferation. The novelty of this study lays in the development of a potential dual drug rapid treatment for corneal ulcers of aggressive nature.

Computers & chemical engineering : CACE 175, 108260 (2023). doi:10.1016/j.compchemeng.2023.108260, Published by Elsevier Science, Amsterdam [u.a.]

© 2023, American Coatings Association.In this work, a novel bio-based phosphorus-containing reagent was synthesized and characterized. To obtain a flame retardant agent with acid functionality, 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and bio-based itaconic acid were first reacted. The synthesized acid then was reacted with glycidyl methacrylate to form a difunctional phosphorus-containing methacrylate flame retardant monomer. The flame retardant monomer was added to a reactive monomer matrix with a photoinitiator to prepare UV-curable coatings. The molecular structure of the flame retardant was confirmed by Fourier-transform infrared-attenuated total reflection spectroscopy and proton nuclear magnetic resonance (1H NMR) spectroscopy. The flame retardant behavior of coatings was determined using limiting oxygen index. Thermal behaviors of the films were studied by thermal gravimetric analysis. Furthermore, scanning electron microscopy/energy-dispersive spectroscopy was used to determine the elemental composition and to observe the morphology of the coatings. The properties (water adsorption, gel content, etc.) of the coatings were also studied. It was found that the addition of DOPO resulted in a significant improvement in the flame retardant and thermal properties of the coatings.

We herein report a waste minimization protocol for the β-azidation of α,β-unsaturated carbonyl compounds using TMSN3. The selection of the appropriate catalyst (POLITAG-M-F), in combination with the reaction medium, resulted in enhanced catalytic efficiency and a low environmental footprint. The thermal and mechanical stability of the polymeric support allowed us to recover the POLITAG-M-F catalyst for up to 10 consecutive runs. The CH3CN:H2O azeotrope has a 2-fold positive effect on the process, increasing the efficiency of the protocol and minimizing waste generation. Indeed, the azeotropic mixture, used as a reaction medium and for the workup procedure, was recovered by distillation, leading to an easy and environmentally friendly procedure for product isolation in high yield and with a low E-factor. A comprehensive evaluation of the environmental profile was performed by the calculation of different green metrics (AE, RME, MRP, 1/SF) and a comparison with other literature available protocols. A flow protocol was defined to scale-up the process, and up to 65 mmol of substrates were efficiently converted with a productivity of 0.3 mmol/min. ispartof: ACS SUSTAINABLE CHEMISTRY & ENGINEERING vol:11 issue:7 pages:3074-3084 ispartof: location:United States status: published

The purpose of this work was the development of an alternative ocular tetrahydrozoline hydrochloride (THZ) microemulsion for the management of allergic conjunctivitis. Pseudo-ternary phase diagrams were used to produce the microemulsions. For the formulation of the microemulsions, isopropyl myristate was selected as oil. Furthermore, various surfactants were applied for the determination of their suitability; ME-1 and ME-4 were developed using Sorbitan monolaurate 80 and Polysorbate 80, for ME-2 and ME-5 Sorbitan monolaurate 80 and macrogolglycerol ricinoleate while for ME-3 and ME-6 Sorbitan monolaurate 80 and Polysorbate 20. For ME-1, ME-2, and ME-3 propylene glycol and ethanol, for ME-4, ME-5, and ME-6 ethanol and polyethylene glycol were used as co-surfactants. Various characterization parameters of microemulsions were evaluated such as droplet size, conductivity, zeta potential, viscosity, and pH. In addition, the drug release, stability, sterility, safety, ex vivo, and in vivo experiments were studied. The characterization showed that the formulations can act as suitable carriers for eye application. In addition, it was revealed that microemulsions were found stable and sterile. The formulations released the drug in a sustained manner. Ex vivo diffusion studies exhibited that the microemulsions can be used for topical delivery to the eye. Assessment of in vitro ocular irritation was conducted by an in vivo prediction model, EpiOcular™ eye irritation test. Based on the in vivo studies, the chosen ideal microemulsion showed longer contact time to the cornea than the commercial product. Moreover, the developed ocular carrier was found to be safe from the viewpoint of in vitro ocular irritancy and mutagenicity. In conclusion, according to characterization results, the THZ microemulsions can act as a hopeful approach for topical eye application.

ispartof: Journal Of Energy Chemistry vol:76 pages:165-174 status: published

© 2022 Elsevier LtdIntegrated gasification combined cycle (IGCC) is a power generation technology that partially oxidizes solid feedstocks to produce syngas, drives high-efficiency gas turbines (GT), recovers waste heat and uses it to generate electricity, etc. In this study, a new IGCC model for an entrained bed gasifier/GT/Kalina cycle for CO2 co-gasification was developed for the first time using Aspen HYSYS, and an energy and exergy analysis of this model was performed to provide decision makers with a comprehensive overview of whether the energy conversion system is designed to be sustainable from a variety of perspectives. The newly proposed integrated system was used to study the CO2/air gasification process of the biochar/waste tyre blend. Although entrained bed gasifiers have been modelled using different software and different fuels, no study on the Kalina cycle integrated biochar/waste tyre co-gasification process using Aspen HYSYS has not been reported yet. In addition, most parametric studies on integrated Kalina combined cycles focus on the influence of the Kalina cycle or a few operating factors. However, in this study, the effects of a variety of gasification process operating conditions on the performance of the combined cycle are considered. The equivalence ratio (ER) for a high-efficiency integrated system ranged from 0.23 to 0.25, and the CO2 content in the gasifying agent was in the range of 5–7%. While increasing the waste tyre content in the feedstock enhances H2 production, operating the entrained bed gasifier at relatively low temperature is more efficient. Increasing the ammonia content in the working fluid also improves efficiency, and the inlet pressure of the Kalina turbine should be maintained at 28 bar to maximize performance. While the integration of the GT enables significant power generation, optimizing the operating conditions of the gasifier, which has the highest exergy dissipation, is critical to the performance of the integrated system.

© 2022 by the authors.This research aims to estimate the delivery time and energy cost of e-scooter vehicles for distributing mail or packages and to show the usage efficiency of e-scooter sharing services in postal service delivery in Turkey. The machine learning (ML) methods used to implement the prediction of delivery time and energy cost as output variables include random forest (RF), gradient boosting (GB), k-nearest neighbour (kNN), and neural network (NN) algorithms. Fifteen input variables under demographic, environmental, geographical, time, and meta-features are utilised in the ML algorithms. The correlation coefficient (R2) values of RF, GB, NN, and kNN algorithms were computed for delivery time as 0.816, 0.845, 0.821, and 0.786, respectively. The GB algorithm, which has a high R2 and the slightest margin of error, exhibited the best prediction performance for delivery time and energy cost. Regarding delivery time, the GB algorithm’s MSE, RMSE, and MAE values were calculated as 149.32, 12.22, and 6.08, respectively. The R2 values of RF, GB, NN, and kNN algorithms were computed for energy cost as 0.917, 0.953, 0.400, and 0.365, respectively. The MSE, RMSE, and MAE values of the GB algorithm were calculated as 0.001, 0.019, and 0.009, respectively. The average energy cost to complete a package or mail delivery process with e-scooter vehicles is calculated as 0.125 TL, and the required time is approximately computed as 11.21 min. The scientific innovation of the study shows that e-scooter delivery vehicles are better for the environment, cost, and energy than traditional delivery vehicles. At the same time, using e-scooters as the preferred way to deliver packages or mail has shown how well the delivery service works. Because of this, the results of this study will help in the development of ways to make the use of e-scooters in delivery service even more efficient.

The recurrent evolution of resistance to cardiotonic steroids (CTS) across diverse animals most frequently involves convergent amino-acid substitutions in the H1-H2 extracellular loop of Na+, K + -ATPase (NKA). Previous work revealed that hystricognath rodents (e.g. chinchilla) and pterocliform birds (sandgrouse) have convergently evolved amino-acid insertions in the H1-H2 loop, but their functional significance was not known. Using protein engineering, we show that these insertions have distinct effects on CTS resistance in homologs of each of the two species that strongly depend on intramolecular interactions with other residues. Removing the insertion in the chinchilla NKA unexpectedly increases CTS resistance and decreases NKA activity. In the sandgrouse NKA, the amino acid insertion and substitution Q111R both contribute to an augmented CTS resistance without compromising ATPase activity levels. Molecular docking simulations provide additional insight into the biophysical mechanisms responsible for the context-specific mutational effects on CTS insensitivity of the enzyme. Our results highlight the diversity of genetic substrates that underlie CTS insensitivity in vertebrate NKA and reveal how amino-acid insertions can alter the phenotypic effects of point mutations at key sites in the same protein domain.

This study was focused on the removal of Cr(VI) ions from electroplating wastewater by ultrasound-assisted adsorption onto activated carbon obtained from melon seed husk. The activated carbon was produced by carbonization of crushed melon seed husk at a temperature of 500 °C for 15 min and further activation using 1.0 M concentration of potassium chloride (KCl) at a temperature of 500 °C for 90 min in a muffle furnace. The obtained adsorption isotherm data were better fitted to the Langmuir model than Freundlich model for adsorption both in the presence and absence of ultrasound (US). The adsorbent maximum adsorption capacity for Cr(VI) ion obtained from the Langmuir isotherms, were 5.059 mg/g and 2.031 mg/g both in the presence of ultrasound and its absence, respectively. The adsorption process in the presence and absence of ultrasound obeyed the pseudo-second-order kinetics. The SEM image of activated carbon before adsorption of metal ion revealed that the surface of activated carbon contains pores with different sizes and shapes, and also showed a significant change on the surface of activated carbon after interaction with Cr(VI) ions.

Prontosil, the sulfonamide compound that started the antibacterial era, was the first commercially available antibacterial agent. Sulfonamide functional groups have gained importance in medicinal chemistry since the first announcement of antibacterial drugs. Synthetic sulfonamides are generally used for the treatment of bacterial infections in biological systems, as well as antifungal, anti-inflammatory antioxidant, diuretics, carbonic anhydrases, antitumor and so on. It has aroused high curiosity in biology and medicine due to its wide range of biological applications. In this study, molecular docking studies were applied to investigate the potential antibacterial properties of sulfonamide derivative compounds synthesized in previous study. The binding energies was anaylzed by Autodock 4.2 code which also performed molecular docking. Docking simulations of sulfonamide compounds at the active site of E. coli β-ketoacyl-acyl carrier protein synthase III (KAS III, PDB ID: 1HNJ) were performed to determine possible binding patterns and inhibitory effects. Docking results were also compared with triclosan used as a commercial antibacterial agent. Biovia Discovery Studio Visualizer 2020 and Autodock 4.2 software were used to analyze results of molecular docking.The binding energies of 3, 4, 5 and 6 sulfonamides used in the study to KAS III enzyme were found to be -6.94, -7.22, -7.76, -8.13, respectively. As a result of molecular docking study, these sulfonamide derivatives may have potential antibacterial properties., Antibakteriyel çağı başlatan sülfonamid bileşiği olan Prontosil, ticari olarak temin edilebilen ilk antibakteriyel ajandır. Sülfonamid fonksiyonel grupları, antibakteriyel ilaçların ilk duyurulmasından bu yana tıbbi kimyada önem kazanmıştır. Sentetik sülfonamidler genel olarak biyolojik sistemlerdeki bakteriyel enfeksiyonların tedavisinde kullanıldığı gibi mantar önleyici, iltihap önleyici antioksidan, diüretikler, karbonik anhidrazlar, antitümör vb olarakta kullanılmaktadırlar. Çok çeşitli biyolojik uygulamaları nedeniyle biyoloji ve tıpta yüksek merak uyandırmıştır.Bu çalışmada, daha önceki bir çalışmada sentezlenen sülfonamid türevi bileşiklerin potansiyel antibakteriyel özelliklerini araştırmak için moleküler yerleştirme çalışmaları uygulanmıştır. Kenetlenme olasılığı, moleküler yerleştirmeyi de gerçekleştiren Autodock 4.2 kodu ile analiz edildi. E. coli β-ketoasil-asil taşıyıcı protein sentaz III'ün (KAS III, PDB ID: 1HNJ) aktif bölgesindeki sülfonamid bileşiklerinin yerleştirme simülasyonları, olası bağlanma modellerini ve engelleyici etkileri belirlemek için gerçekleştirilmiştir. Yerleştirme sonuçları, ticari bir antibakteriyel madde olarak kullanılan triklosan ile de karşılaştırıldı. Moleküler yerleştirme sonuçlarını analiz etmek için Biovia Discovery Studio Visualizer 2020 ve Autodock 4.2 yazılımı kullanıldı.Çalışmada kullanılan 3, 4, 5 ve 6 isimli sülfanamidlerin KAS III enzimine bağlanma enerjileri sırasıyla -6,94, -7,22, -7,76, -8,13 bulunmuştur. Moleküler docking çalışmasının sonucu bu sülfonamid türevlerinin potansiyel antibakteriyel özelliğe sahip olabileceğini göstermiştir.

There is an environmental concern regarding the use of petroleum-based lubricants, which are generally toxic and nonbiodegradable. Biobased lubricants, such as vegetable oils, are the alternative: they show excellent lubricity, are readily biodegradable and nontoxic. However, a major disadvantage of using vegetable oils in lubricant applications is their lack of thermo-oxidative stability, which can be improved by antioxidant additives. Here, we propose the use of lignin-based additives in biolubricant formulations to improve this feature, based on lignin’s known antioxidant properties. To ensure a stable dispersion in vegetable oil, lignin was partially esterified. Antioxidant properties of lignin before and after palmitoylation were demonstrated in a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Four different lignin-based fractions, commercial Protobind P1000 soda lignin from straw, solvolytically fractionated Protobind P1000 lignin and two lignin fractions from reductively catalyzed fractionation (RCF) of native birch wood, were tested in biolubricant formulations with castor oil as base oil. Those lignin fractions exhibited excellent performance compared to butylated hydroxytoluene (BHT), a commonly used petroleum-based antioxidant. Formulations of modified lignin in castor oil possess improved thermo-oxidative stability, as illustrated by their increased oxidation induction time. Additionally, rheological and tribological tests demonstrate similar, or in some cases improved, lubricating properties compared to castor oil. This study showcases the successful incorporation of lignin-based antioxidants in biolubricant formulations, tackling the major disadvantage of vegetable oils as environment-friendly lubricants.

Syngas from biomass gasification is being developed for alternative feedstock in the chemical industry. Palm kernel shell which is generated from palm oil industry can be potentially used as raw material for gasification process. The purpose of this study was to investigate the use of modified natural zeolite catalysts in steam gasification of palm kernel shells. Mordenite type zeolite was modified by acid leaching to be used as a tar cracking catalyst. Steam gasification was conducted at the temperature range of 750–850 °C and the steam to biomass ratio was in the range of 0–2.25. The result showed that steam gasification of palm kernel shell with the addition of zeolite catalyst at 750 °C and steam to biomass ratio 2.25 could reduce tar content up to 98% or became 0.7 g/Nm3. In this study, gasification of palm kernel shells produced syngas with the hydrogen concentration in the range of 52–64% and H2/CO ratio of 2.7–5.7. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

© 2022 The Authors. Published by American Chemical Society.Catalysts based on metal-free conjugated porous polymers (CPPs) are still rare for electrochemical oxygen reduction reactions (ORR). In this study, a conjugated porous polymer, TT-TPB, based on thieno[3,2-b]thiophene (TT) and triphenylbenzene (TPB), was synthesized applying palladium(0) catalyzed Suzuki coupling reaction and its ORR activity was investigated in alkaline condition. It demonstrated comparable electrocatalytic performance of ≈0.89-0.9 V Eonset vs RHE with the commercially available Pt/C. Density-functional theory (DFT) calculations revealed that TT-TPB featured efficient electrocatalytic active sites derived from volumetric, areal, and O2 adsorbing calculations, which were in line with the experimental results. Moreover, semiconducting and surface properties of TT-TPB were investigated in detail using electrochemical and spectrophotometric techniques. This work shows the potential application of thienothiophene-based metal-free CPP in the electrochemical conversion process.

In this study, two novel silicon phthalocyanines (SiPc) having axial anchoring groups (3: SiPc carrying bis-dibutyl phenoxy acrylic acid and 5: SiPc carrying bis-dibutyl phenoxy carboxylic acid) are synthesized as the photosensitizers of dye sensitized solar cells (DSSCs). The obtained novel photosensitizers are elucidated by using 1H NMR, MALDI-TOF, FT-IR, UV-Vis spectroscopy, and elemental analysis. Moreover, the electrochemistry of SiPcs is investigated with voltametric and in-situ spectroelectrochemical analysis. Both SiPcs illustrate similar two reductions and one oxidation Pc based redox processes. In-situ spectroelectrochemical results support the Pc based characters of the voltametric responses. The chromaticity diagrams and optical responses of the anionic and cationic moieties are recorded with the in-situ spectroelectrochemistry to determine the viability of them for various photoelectrochemical usage. Finally, SiPcs are investigated as dyes in DSSCs in order to investigate the influence of bis-dibutyl phenoxy acrylic acid and bis-dibutyl phenoxy carboxylic acid anchoring groups to the photovoltaic performance of SiPcs. DSSCs sensitized with SiPc (3) and SiPc (5) illustrate good photovoltaic performance with 1.48 and 1.99 mA/cm2 short circuit current density, 0.751 and 0.657 V open circuit potential, 0.52 and 0.57 fill factor, and 0.57% and 0.75% power conversion efficiency respectively.

For the transition towards greener biorefineries with reduced waste, valorization of lignin to drop‐in chemicals instead of their combustion for energy purposes is a key issue for future processes. In this context, lignin should be extracted from lignocellulosic biomass (LCB) and fragmented into smaller units, followed by catalytic funneling to fine chemicals. In this review, we report on the classical approaches for lignin valorization from LCB: thermal treatments, solvolytic valorization, acid‐catalyzed process, and base‐catalyzed process. We also provide the reader with the modern approach of lignin valorization that led to an integrated LCB biorefinery. The performance of different solid catalysts in lignin‐first approach via reductive or oxidative catalytic fractionation at different conditions is discussed in detail.

© 2022 Elsevier B.V.This work aims to design and develop a photocatalyst with the main three properties: i) reduced bandgap for solar activation of the photocatalyst, ii) retarded e- / h+ recombination rate for the enhanced photocatalytic activity, iii) magnetic separability from the reaction medium. In this study, NiFe2O4/TiO2-Ag+ photocatalysts were synthesized to modify the structural properties of TiO2. Firstly, NiFe2O4 nanoparticles were synthesized by a conventional co-precipitation method, then in the presence of NiFe2O4 nanoparticles, TiO2 was synthesized by a novel complex-assisted vapor thermal (VT) method via slow hydrolysis of Ti-complex. After the best wt% amount of NiFe2O4 in the NiFe2O4/TiO2 had been determined for photocatalytic activity, Ag+ was added by wet-impregnation. The photocatalysts were characterized by X-ray diffraction (XRD), UV–vis Diffuse Reflectance Spectroscopy (DRS), Photoluminescence Spectroscopy (PL), vibrating sample magnetometer analysis (VSM), transmission electronic microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Photocatalytic hydrogen production reactions were carried out in methanol/water solution under solar light illumination. Consequently, the best configuration of the photocatalyst was determined as 12 wt% NiFe2O4/TiO2-0.5 wt% Ag+ (12NFT-0.50Ag+) which had shown the maximum hydrogen (H2) production rate as 137 µmol/g-cat after 5 h owing to its reduced bandgap energy and delayed e- / h+ recombination.

Nanotechnology has gained great interest due to its widespread application. Anticancer activity of Origanum majorana extract and silver nanoparticles was investigated by MTT assay using human pancreatic adenocarcinoma cell lines (Capan-1), mouse normal fibroblast cell lines (L929), and human colon adenocarcinoma cell line (Caco-2). AgNPs@Om exhibited the excellent cytotoxic effect on Capan-1 cell lines with the cell viability of 29.17% and 25.70%, 22.49%, 21.16% at 1.0, 0.5, 0.25, 0.125 µg/mL respectively. However, the extract was determined to show moderate activity. A considerable fall in the viable cell number in Caco-2 cell lines was observed after the treatment of AgNPs@Om. The viable cells of Caco-2 cell lines were detected as 32.0% at 1.0 µg/mL with the treatment of nanoparticles. Yet, the viable Caco-2 cells were determined as 48.2% with the treatment of O. majorana extract. Both extract and nanoparticles had no impact on the viability of non-tumor cells (L929). Moreover, nanoparticles induced apoptosis. Consequently, AgNPs@Om may be a promising anticancer drug candidate.

The release of greenhouse gas emissions into the atmosphere as a result of anthropogenic sources and industrial applications has triggered the increase in global temperatures called global warming and related climate change. Phosphogypsum (PG) is a by-product of the wet process phosphoric acid (H3PO4) production process, which chemically consists of calcium sulfate dihydrate (CaSO4•2H2O) with some impurities. Annual PG accumulation has reached 300 Mtons and a strategy is needed to ensure efficient, continuous and bulk consumption. Due to the high amount of calcium it contains, PG is a material suitable for use in CO2 capture and storage processes to form stable solid carbonate compounds. This process, called mineral carbonization of PG, contributes to sustainable development goals by providing the multiple benefits of both the utilization of an industrial by-product and the realization of CO2 capture and storage technology.

Pepino is an exotic fruit that contains high vitamin C and is known to have many beneficial effects on health. In this study, thin layer drying and color changes of pepino fruit by infrared (IR) and microwave (MW) methods were investigated. Effective moisture diffusions and activation energy were calculated from the drying data. Uniformly sliced pepino fruit was processed without peeling. While IR drying processes were performed at 60, 70, and 80 °C temperatures in 210, 165, and 120 minutes, respectively, MW drying processes were completed at 25, 16, and 6 minutes at 140, 210, and 350 W power levels. While the initial average moisture content was 18.5702 kg water/kg dry, the lowest moisture content was determined as 0.3250 at 80 °C in IR and 0.1263 water/kg dry matter×min at 350 W at MW. Effective moisture diffusions (Deff) for IR were calculated between 6.69 × 10-10 - 1.23 × 10-9 m2/s, while for MW it was found between 8.75 × 10-9 - 3.75 × 10-8 m2/s. The activation energy (Ea) was 29.80 kJ/mol for IR and 33.30 kW/kg for MW. In addition, it was determined that color preservation was better in the IR method, and local burns were observed in the samples in the microwave method.

DNA strands are essential in a cell for growth, metabolism regulation and carrying genetic information bases to new generations, in every creatures . The function of DNA bases is a 0 and 1 system. In this theoretical research , we try to make two other 0 and 1 systems for DNA bases .In both methods, C2Fe+ is attached to DNA bases and nucleotides like a flag to make derivatives. In the first method NMR susceptibility and Magnetization of pristine DNA bases, nucleotides and their C2Fe varieties are determined theoretically by using Gauss view and Gaussian programs. With effect of a magnetic field (H) and NMR susceptibility of these compounds, their calculate magnetizations , certain signals can be created as a mark of DNA bases and their compounds. These resulted not only can be considered as a method to make a new (0) and (1) system. In the second method, by using Gauss view and Gaussian programs the theoretically UV-Visible spectrum of pristine DNA bases, nucleotides and their C2Fe varieties are determined which the spectrum absorption of the pristine compounds are in different range with the absorption range of C2Fe varieties. With a little change in spectrophotometer construction another 0 and 1 coding system can be created, again.

Bu çalışmada 3,5-dihidroksi-2-(naftalen-2-ildiazenil) benzoik asidin sentezi, karakterizasyonu ve teorik hesaplaması anlatılmaktadır. Sentezlenen bileşik, başlangıç malzemeleri olarak 2-Naftilamin ve 3,5-dihidroksibenzoik asit kullanılarak verimli sentetik yoldan elde edildi ve Fourier Dönüşümlü Kızılötesi Spektroskopisi (FTIR), Proton Nükleer Manyetik Rezonans Spektroskopisi (1H-NMR), Karbon Nükleer Manyetik Rezonans Spektroskopisi (13C-NMR), Ultraviyole-Görünür Spektroskopi (UV-Vis) gibi çeşitli spektroskopik tekniklerle karakterize edildi. Tüm teorik hesaplamalar Yoğunluk Fonksiyonel Teorisi (DFT) ile yapıldı. Optimize edilmiş moleküler yapı, titreşim spektrumları, NMR kimyasal kayma değerleri, sınır moleküler orbitalleri, bağ uzunlukları, bağ açıları ve molekülün Moleküler Elektrostatik Potansiyel (MEP) diyagramı 6-311G(d,p) temel seti kullanılarak hesaplandı. Deneysel ve teorik hesaplamalardan elde edilen sonuçların birbirini desteklediği ve uyum içinde olduğu görüldü., This study describes the synthesis, characterization and theoretical calculation of 3,5-dihydroxy-2-(naphthalen-2-yldiazenyl) benzoic acid. The synthesized compound was obtained through efficient synthetic route using 2-Naphthylamine and 3,5-dihydroxybenzoic acid as starting materials and characterized by various spectroscopic techniques such as Fouirer Transform Infrared Spectroscopy (FTIR), Proton Nuclear Magnetic Resonance Spectroscopy (1H-NMR), Carbon Nuclear Magnetic Resonance Spectroscopy (13C-NMR), Ultraviolet–visible spectroscopy (UV-Vis). All theoretical calculation was performed with Density Functional Theory (DFT). Optimized molecular structure, vibrational spectra, NMR chemical shift values, frontier molecular orbitals, bond lengths (Å), bond angles (°) and Molecular Electrostatic Potential (MEP) diagram of molecule were calculated using the 6-311G(d,p) basis set. It has been observed that the results obtained from the experimental and theoretical calculations support each other and were in harmony.

Low salinity water flooding is a promising enhanced oil recovery technique that has been observed, in experiments over a range of scales, to increase oil production by up to 14% in some systems. However, there is still no way of reliably predicting which systems will respond favourably to the technique. This shortcoming is partly because of a relative lack of pore scale observations of low salinity water flooding. This has led to a poor understanding of how mechanisms on the scale of micrometres lead to changes in fluid distribution on the scale of centimetres to reservoir scales. In this work, we use X-ray micro-CT scanning to image unsteady state experiments of tertiary low salinity water flooding in Berea, Castlegate, and Bunter sandstone micro-cores. We observe fluid saturations and characterise the wetting state of samples using imagery of fluid–solid fractional wetting and pore occupancy analysis. In the Berea sample, we observed an additional oil recovery of 3 percentage points during low salinity water flooding, with large volumes of oil displaced from small pores but also re-trapping of mobilised oil in large pores. In the Bunter sandstone, we observed 4 percentage point additional recovery with significant displacement of oil from small pores and no significant retrapping of oil in large pores. However, in the Castlegate sample, we observed just 1 percentage point of additional recovery and relatively small volumes of oil mobilisation. We observe a significant wettability alteration towards more water-wet conditions in the Berea and Bunter sandstones, but no significant alteration in the Castlegate sample. We hypothesise that pore structure, specifically the topology of large pores impacted recovery. We find that poor connectivity of the largest pores in each sample is strongly correlated to additional recovery. This work is the first systematic comparison of the pore scale response to low salinity flooding across multiple sandstone samples. Moreover, it gives the first pore scale insights into the role of pore geometry and topology on the mobilisation of oil during low salinity water flooding.

In decades, the presence of anti-inflammatory drugs diclofenac (DCF) in water resources has become an extremely threatening factor in terms of environmental protection and pollution. In this study, the removal efficiencies of DCF in aqueous sources were studied by adsorption, conventional coagulation, and combined coagulation methods using carbon nanotubes (CNTs). Experimental studies were carried out by adding certain doses of 1 g/L stock DCF solution prepared in the laboratory to water samples. In order to determine the adsorbing capacity of DCF, three different adsorbents as single-walled CNT (SWCNT), multi-walled CNT (MWCNT), and powdered activated carbon (PAC) were used as a function of pH and ionic strength. As a result of batch adsorption experiments performed in both ULW and UDWTP samples, the highest DCF sorption capacity was observed in SWCNT at pH =3 as 4.82 mg.g-1 and 3.82 mg.g-1, respectively, and also DCF adsorption capacity increased when the ionic strength was increased from 6.0×10-1 to 1.0 M. Furthermore, the experimental results showed that the Freundlich equation about correlation coefficient (R2=0.99) is the best isotherm model to describe the adsorption process in all water sources. On the other hand, results in coagulation experiments demonstrated that the maximum removal percentages of DCF in ULW (94.81%) and UDWTP (91.97%) occurred with combined SWCNT with Alum compared to only Alum coagulation. Experimental data obtained in this study reveal that combined coagulation with CNTs is more appropriate to minimize the pollution caused by DCF, especially in the aquatic environment, rather than adsorption and coagulation processes.

Bu çalışmada, yeni 3-oksobutanohidrazid türevleri için yeni bir sentetik yöntem geliştirilmiştir. Bu sentetik yöntem iki adımdan oluşmaktadır. İlk aşamada aldehit fenil hidrazon türevleri sentezlendi. Daha sonra, bu bileşikler 2,2,6-trimetil-4H-1,3-dioksin-4-on (TMD) bileşiği ile katalitik miktarda seryum amonyum nitrat varlığında reaksiyona sokularak hedef moleküller olan 3-okzobutanohidrazit türevleri sentezlendi. Sentezlenen 3-oksobutanohidrazid türevlerinin yapıları 1H-NMR ve 13C-NMR ile karakterize edildi., In this study, a new synthetic method was developed for new 3-oxobutanohydrazide derivatives. This synthetic method consists of two steps. In the first step, aldehyde phenyl hydrazone derivatives were synthesized. Then, these compounds were reacted with 2,2,6-trimethyl-4H-1,3-dioxin-4-one (TMD) compound in the presence of the catalytic amount of cerium ammonium nitrate and 3-oxobutanohydrazide derivatives, which are new target molecules, were synthesized. The structures of the synthesized 3-oxobutanohyidrazide derivatives were characterized by 1H-NMR and 13C-NMR.

International audience; High energy consumption during harvesting is one of the main bottlenecks for sustainable microalgae production. Membranes can efficiently separate microalgae from liquids with low energy consumption, but membrane fouling remains an important issue. Flocculation prior to membrane filtration can increase membrane fluxes and decrease fouling, thus offering a low-cost and efficient solution to harvest microalgae. Biobased cationic cellulose nanocrystals were successfully used as flocculants for microalgae and were effective over a wide pH-range and for both freshwater and marine microalgae. Such flocculation was for the first time combined with vibration-assisted filtration using a charged, surface patterned membrane, enabling operation at very high flux (95 L/m2 h) using a vibration frequency of only 1 Hz, and even under sub-optimal flocculation conditions. Intermittent vibration decreased energy consumption further while keeping excellent filtration performance to finally achieve a record-low energy consumption for the membrane filtration of only 6.7 Wh/m3, which is andgt;25-times lower than that of normal membrane filtration. Interaction forces revealed that increasing particle size through flocculation prior to membrane filtration can significantly prevent microalgae attachment on the vibrating membrane surface. This work opens a new direction for sustainable microalgae harvesting with an ultra-low energy consumption, combined with a very high microalgae recovery, reduced use of chemicals, and lower membrane investment cost.

In this study, a laboratory-scale cooling system, simulating a household refrigerator, was examined experimentally for an average cabinet temperature of 4 degrees C with two different types of phase change materials (PCMs) (water and eutectic solution). The system was tested with various amounts of water and different concentrations of sodium sulfate (Na2SO4) in water. The influence of different amounts and types of the PCMs on the cabinet air temperature and compressor power consumption was analyzed during the running period. The cabinet air temperature change over time was also observed during the power failure period. The examinations suggest using 1.0 wt.% Na2SO4 solution as the PCM in the cooling systems. This solution provides the lowest energy consumption (19.5 kJ), and the running time percentage (21.7%); while maximizing the energy saving (14.2%). In addition, integrating it as PCM could allow preserving products for long periods without significant quality loss during a power failure; because it prevented the rapid increase of the cabinet air temperature in this scenario. Lastly, when the cycle frequency is considered, it has the best time interval and the number of cycles (5.3). Thus, it has a positive effect on reducing the compressor cycling frequency, which eventually increases the compressor lifespan.

Bipolar membrane electrodialysis (BMED) is a new membrane separation technology composed of electrodialysis (ED) through a bipolar membrane (BPM). Under the action of an electric field, H2O can be dissociated to H+ and OH-, and the anions and cations in the solution can be recovered as acids and bases, respectively, without adding chemical reagents, which reduces the application cost and carbon footprint, and leads to simple operation and high efficiency. Its application is becoming more widespread and promising, and it has become a research hotspot. This review mainly introduces the application of BMED to recovering salts in the form of acids and bases, CO2 capture, ammonia nitrogen recovery, and ion removal and recovery from wastewater. Finally, BMED is summarized, and future prospects are discussed. ispartof: MEMBRANES vol:12 issue:9 ispartof: location:Switzerland status: published

In this contribution, we have reported our study on the fine-tuned design and synthesis of new POLITAGs-Pd0(POLymeric Ionic TAG) catalytic systems with the intention of defining highly efficient heterogeneous palladium catalysts stabilized by ionic tags able to operate at a very low loading while being fully recoverable/reusable. By varying both the support and the ratio between the metal and immobilized ionic tag, we have accessed five different heterogeneous catalytic systems that have been fully characterized (EA, XPS, TEM, and HR-TEM) to investigate their morphological differences. The catalytic efficiency of the newly prepared POLITAGs-Pd0materials was then tested and compared in the representative Mizoroki-Heck cross-coupling reaction, a universally investigated and widely useful process. A close correlation between the catalyst support and catalytic performances has been highlighted. The best system POLITAG-Pd0-HM features a high TOF value (26,786 h-1), affording the final products in high isolated yields by using as little as only 0.0007 mol % of Pd. Moreover, this high catalytic activity coupled with the use of γ-valerolactone (GVL) as a green reaction medium has led to the definition of a very efficient waste-minimized protocol. The newly designed catalyst has been utilized in the representative synthesis of Amiloxate, a widely used sunscreen agent, that could be prepared with negligible metal contamination and very low E-factor.

In this work we describe the production of spherical polymer particles from thermoplastic polymers. A simple method is developed to transform rough powders into spherical particles. The polymer particles are molten in heated oil whereafter interfacial tension driven reduction of curvature and shape retraction induce a transformation to the equilibrium spherical shape. The sphericity of the particles is validated by determining the aspect ratio, roundness, as well as circularity. Furthermore, batches of narrow particle size distribution are attained by sieving on different mesh sizes. The effects of the material characteristics and processing conditions are investigated and rationalized based on the governing physical processes and their scaling relations. As a result, the processing conditions can a priori be tailored depending on the material characteristics. The versatility of the method is confirmed by generating spherical particles from various thermoplastic polymers including PS, LDPE, PP, PA12 and PA12 filled with carbon nanotubes.

İşlenen konulara göre yağlı boya tuval resimleri, dönemin sanatı, üslubu, sosyal yaşamı, inancı ve tarihi hakkında bilgi veren taşınabilir en önemli kültür varlıklarından biridir. Bu çalışmada çeşitli nedenlerden dolayı yağlı boya tuvallerde görülen kirlenmelerin biyopolimerik yapıda hidrojeller kullanılarak temizlenmesi amaçlanmıştır. Hidrojeller toksik madde içermemesi ve bunun yanında hızlı ve kolay bir teknikle hazırlanması yönünden birçok avantaja sahiptir. Hazırlanan hidrojeller ile tarihi eser niteliği taşıyan tuval resimlerindeki kirlenmeler yapıya zarar vermeden temizlenmiştir. Kolay ve bol bulunan aljinat ve doğal sakız biyopolimerleri ile hidrojel yapısında temizleme malzemesi hazırlanmıştır. Temizleme işlemlerinin test edilmesi için kimyasal yöntemler ile yaşlandırışmış tuvaller toz, kül ve is ile kirletilmiştir. Kullanılan hidrojel malzemeler kirletilen ve yaşlandırılan tuvallere uygulanması neticesinde sonuçlar farklı mikroskobik ve spektroskopik yöntemlerle incelenmiştir. Optik mikroskop, Taramalı Elektron Mikroskobu (SEM) ve Fourier Dönüşümlü Kızılötesi Spektrofotometresi (FT-IR) analiz yöntemleri kullanılarak malzemelerin karakterizasyonu gerçekleştirilmiştir., According to the subjects covered, oil painting canvas are one of the most important movable cultural heritage that provide information about the art, style, social life, belief and history of the period. In this study, it was aimed to clean the dirt due to various reasons on oil canvas by using biopolymeric hydrogels. Hydrogels have many advantages in that they don’t contain toxic substances and can be prepared with a fast and easy technique. The dirt on the canvas paintings that are historical artifacts were cleaned without damaging the building with the hydrogels prepared. Hydrogel structure was prepared as a cleaning material with plentiful and readily available alginates and natural gums biopolymers. The canvases aged by chemical methods were contaminated with dust, ash and soot to test the cleaning processes. As a result of the application of the hydrogel materials used on polluted and aged canvases, the results were analyzed with different microscopic and spectroscopic methods. The characterization of the materials was carried out using analysis methods as optical microscope, Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectrophotometer (FT-IR).

The aim of this study is to develop a simple, rapid, and accurate method for quantitative determination of bacteriocin activity. The method involves the use of 2,3,5-triphenyltetrazolium chloride (TTC), which is a colorless water-soluble salt. Only viable cells take up the compound and reduce it intracellularly to its red-colored and water-insoluble formazan dye. Bacteriocin, nisin and lacidin-A were assayed using the sensitive indicator Lactobacillus delbrueckii subsp. lactis ATCC 4797 whereas pediocin PO2 was assayed against Lactobacillus bulgaricus OSU 135. The major factors affecting the reduction of TTC, such as the reagent concentration, incubation period, temperature, and pH were adjusted so that optimal reduction of TTC by the indicator microorganisms could be achieved. Two-fold dilutions of the bacteriocins were mixed with a standardized indicator culture and incubated for 30 min. Then 0.2% TTC was added and the mixture (pH 6.0) was incubated at 37 oC for 20 min. After the incubation, formazan was extracted from the cells with methanol and the absorbance was measured at 485 nm. The amount of formazan formed by the survivor cells was compared with survivor counts and zone of inhibition method. The dose-response plot for the TTC-based bacteriocin assay was linear over a wide range bacteriocin concentration. A high correlation ( R2 > 0.95 ) was between viable cell count and TTC reduction for three of the bacteriocins tested. The new assay can be completed in one hour, compared to one or two days with microbiological assays. Overall, the procedure is simple and easy to carry out.

Using polyethyleneimine (PEI) as the sole precipitation and aggregation agent, PEI-enzyme complexation was investigated with lipases from Rhizomucor miehei, Thermomyces lanuginosus and Candida antarctica. The approach relied on rapid development of PEI-lipase aggregates in a solution and followed by glutaraldehyde cross-linking thus resulting in cross-linked PEI-lipase aggregates. PEI to enzyme mass ratio of a 1/ 20-40 range, alkaline pH and the absence of impurities produced higher coupling yields and activities. The pH affected the precipitatibility and/or relative activity of the aggregates. Impurities in some lipase preparations may prevent the formation or precipitation of the PEI-lipase aggregates. The aggregates attained higher stabilities especially at high pHs and enhanced thermostability with at least a 20-fold at ambient temperatures. By using p-nitrophenyl propionate as a soluble substrate, app. Vmax for the immobilized lipase increased by two-fold with only 25% increment in app. Km compared with the soluble lipase. Complexation with PEI may have produced favorable interface assisting for conformational change for the lipase activation. Thus, cross-linked PEI-lipase aggregates with ease of recovery and stability can be simple and inexpensive alternative for carrier-free immobilized lipases.