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This research proposes a low-cost and simple operation microfluidic chip to enhance the magnetic labeling efficiency of two ischemic stroke biomarkers: cellular fibronectin (c-Fn) and matrix metallopeptidase 9 (MMP9). This fully portable and pump-free microfluidic chip is operated based on capillary attractions without any external power source and battery. It uses an integrated cellulose sponge to absorb the samples. At the same time, a magnetic field is aligned to hold the target labeled by the magnetic nanoparticles (MNPs) in the pre-concentrated chamber. By using this approach, the specific targets are labeled from the beginning of the sampling process without preliminary sample purification. The proposed study enhanced the labeling efficiency from 1 h to 15 min. The dynamic interactions occur in the serpentine channel, while the crescent formation of MNPs in the pre-concentrated chamber, acting as a magnetic filter, improves the biomarker-MNP interaction. The labeling optimization by the proposed device influences the dynamic range by optimizing the MNP ratio to fit the linear range across the clinical cutoff value. The limits of detection (LODs) of 2.8 ng/mL and 54.6 ng/mL of c-Fn measurement were achieved for undiluted and four times dilutions of MNP, respectively. While for MMP9, the LODs were 11.5 ng/mL for undiluted functionalized MNP and 132 ng/mL for four times dilutions of functionalized MNP. The results highlight the potential use of this device for clinical sample preparation and specific magnetic target labeling. When combined with a detection system, it could also be used as an integrated component of a point-of-care platform. [ABSTRACT FROM AUTHOR]

The results of industrial tests, a developed technology for purifying and remelting babbits, produced from worn-out liners in sliding bearings in industrial equipment, are presented. In the present work, the development of a site at the enterprise for regenerating old bearings and the refusal of imported sliding bearings are addressed. The results were obtained at JSC "Ferganaazot," many experimental melts were carried out under various burdening options. The bearing shells made of secondary babbitts meet the quality standards in structure and properties of sliding bearing shells. In general, the properties of secondary babbitt meet the requirements of consumers for renewing sliding bearings. The research results will be used at other enterprises of the Republic of Uzbekistan to develop sites for processing babbits and establish new technological processes for renewing and increasing the service life of sliding bearings. [ABSTRACT FROM AUTHOR]

Proteins are one the most widely studied biomolecules with diverse functions and applications. Aiming at overcoming the current drawbacks of purification processes of proteins, the introduction of ionic liquids (ILs) has been a hot topic of research. ILs have been applied in the creation of aqueous biphasic systems (IL-based ABS), solid-phase extractions through poly(ionic liquid)s (PILs) and supported ionic-liquid phases (SILPs), and in the crystallization of proteins. In this sense, ILs have emerged as solvents, electrolytes or adjuvants, or as supported materials to tune the adsorption/affinity capacity aiming at developing an efficient, cost-effective, sustainable and green IL-based process for protein extraction. This review discusses different IL-based processes in the extraction and purification of proteins in the past years, namely IL-based aqueous biphasic systems (IL-based ABS), solid-phase extractions through PILs and SILPs, and protein crystallization. The type and structure of ILs applied and their influence in the different processes performance are also discussed. [ABSTRACT FROM AUTHOR]

Due to its toxicity and corrosiveness, removal of hydrogen sulfide (H2S) from landfill biogas is essential in terms of environmental impacts and biogas valorization. This study evaluates the performance of a chemical-biological oxidation process for the purification of biogas. The treatment process consists of two separate phases. The first phase targets the elimination of 50 ppmv H2S concentration from the gaseous stream by ferric sulfate solution in the chemical absorption/oxidation reactor. This technique was 100% efficient for removing the H2S at 15 g L−1 ferric iron concentration and empty bed residence time of 7 min. The model validation indicated that the mass transfer limitation is the rate-determining phase in the chemical treatment process. Then, in the second phase, biological oxidation of the produced ferrous sulfate into ferric sulfate took place. The oxidation rates of up to 1 g Fe2+ L−1 h−1 and 0.8 g Fe2+ L−1.h−1 were achieved in the biological oxidation process with and without adding 0.1% w/v glucose, respectively. [ABSTRACT FROM AUTHOR]

The potential utilization and development of the Ba isotope tool depend on an accurate δ137/134Ba determination of the samples. During the chemical purification, whether the adsorption process on the surface of the ion-exchange resin could lead to the Ba isotopic fractionation and the degree of fractionation directly influence the accurate δ137/134Ba determination. In the present work, first-principles calculations based on the density functional theory were used to quantify the Ba isotopic equilibrium fractionation factor between the aqueous solution and the resin in the acid leaching process. By constructing and optimizing the geometric configurations of Ba-containing species, (Ba(H2O)n2+, Ba(H2O)nCl2, Ba(H2O)n(NO3)2, and the adsorbed Ba2+ on the surface of the resin, extracting the harmonic vibrational frequencies, we finally at 298 K obtained the fractionations, Δ137/134Basoln-ads = 0.07‰, Δ137/134BaBa(H2O)nCl2-ads = 0.05‰, and Δ137/134BaBa(H2O)n(NO3)2-ads = 0.02‰. Overall, there were almost no Ba isotope fractionations during leaching. Although the Ba isotope fractionation can be magnified by the Rayleigh fractionation process in purification, the difference in δ137/134Ba between the initial and final stages did not exceed 0.060‰ (or 0.045‰) when leaching the standard sample with HCl or HNO3, which is equal to or less than the accuracy of Ba isotopic analysis. At a common yield of 89.75%, Ba isotopic fractionation induced by incomplete recovery was 0.015‰ for HCl (or 0.011‰ for HNO3). Finally, if the influence of an incomplete recovery on the δ137/134Ba determination needs to be ignored, the recovery is suggested to be not less than 67% for HCl (or 46% for HNO3). [ABSTRACT FROM AUTHOR]

Background: The residual chemical pollutants in drinking water may cause adverse effects on human health. Chemical compounds potentially affecting human health have been widely explored, while the multiphasic evaluation of chemical compounds by process control and human health risk is still rarely reported. In the present study, we used multiphasic criteria to assess the health risk including effluent concentration, accumulation index, purification index for the removal efficiency during the drinking water treatment processes, carcinogen classification based on the International Agency for Research on Cancer standards, non-carcinogenic health hazards and carcinogenic risk. Results: Among the monitored chemicals, 47 and 44 chemical compounds were detected in raw water and treated water, respectively. The generation and removal of chemical compounds implied that the migration and transformation of chemicals during the purification processes affected the effluent concentration, posing a direct potential health risk. Of these compounds, 41 contaminants' profiles were screened as priority chemical compounds (PCCs). Conclusions: The top eight PCCs with high carcinogenic risk were highlighted. Some effective steps, such as protecting the raw water sources, improving the removal performance and reducing the disinfection by-products during the purification process by introducing advanced treatment technologies, were suggested to maintain drinking water security. Collectively, our findings provided novel scientific supports for the sustainable management of drinking water to promote human health. [ABSTRACT FROM AUTHOR]

Cutting fluid has cooling and lubricating properties and is an important part of the field of metal machining. Owing to harmful additives, base oils with poor biodegradability, defects in processing methods, and unreasonable emissions of waste cutting fluids, cutting fluids have serious pollution problems, which pose challenges to global carbon emissions laws and regulations. However, the current research on cutting fluid and its circulating purification technique lacks systematic review papers to provide scientific technical guidance for actual production. In this study, the key scientific issues in the research achievements of eco-friendly cutting fluid and waste fluid treatment are clarified. First, the preparation and mechanism of organic additives are summarized, and the influence of the physical and chemical properties of vegetable base oils on lubricating properties is analyzed. Then, the process characteristics of cutting fluid reduction supply methods are systematically evaluated. Second, the treatment of oil mist and miscellaneous oil, the removal mechanism and approach of microorganisms, and the design principles of integrated recycling equipment are outlined. The conclusion is concluded that the synergistic effect of organic additives, biodegradable vegetable base oils and recycling purification effectively reduces the environmental pollution of cutting fluids. Finally, in view of the limitations of the cutting fluid and its circulating purification technique, the prospects of amino acid additive development, self-adapting jet parameter supply system, matching mechanism between processing conditions and cutting fluid are put forward, which provides the basis and support for the engineering application and development of cutting fluid and its circulating purification. [ABSTRACT FROM AUTHOR]

Chemical gardens are an example of a chemobrionic system that typically result in abiotic macro-, micro- and nano- material architectures, with formation driven by complex out-of-equilibrium reaction mechanisms. From a technological perspective, controlling chemobrionic processes may hold great promise for the creation of novel, compositionally diverse and ultimately, useful materials and devices. In this work, we engineer an innovative custom-built liquid exchange unit that enables us to control the formation of tubular chemical garden structures grown from the interface between calcium loaded hydrogel and phosphate solution. We show that systematic displacement of phosphate solution with water (H2O) can halt self-assembly, precisely control tube height and purify structures in situ. Furthermore, we demonstrate the fabrication of a heterogeneous chemobrionic composite material composed of aligned, high-aspect ratio calcium phosphate channels running through an otherwise dense matrix of poly(2-hydroxyethyl methacrylate) (pHEMA). Given that the principles we derive can be broadly applied to potentially control various chemobrionic systems, this work paves the way for fabricating multifunctional materials that may hold great potential in a variety of application areas, such as regenerative medicine, catalysis and microfluidics. Chemobrionic materials with applications in tissue engineering can be grown at the interface of calcium and phosphate solutions, however, controlling their dimensions and purity can be difficult. Herein, a flow device allows control of the height and in situ purification of chemical gardens, which can be encased in a photoset hydrogel for subsequent use. [ABSTRACT FROM AUTHOR]

Coronavirus and its spread all over the world have been the most challenging crisis in 2020. Hospitals are categorized among the most vulnerable centers due to their presumably highest traffic of this virus. In this study, centrifugal isolation of coronavirus is successfully deployed for purifying hospitals' air using air conditioners and ducts, suggesting an efficient setup. Numerical simulations have been used to testify the proposed setup due to the complexities of using experimental investigation such as high cost and clinical hazards of the airborne SARS-CoV-2 in the air. Results show that a 20-cm pipe with an inlet velocity of 4 m/s constitutes the best choice for the separation and purification of air from the virus. The proposed scalable method also efficiently separates larger particles, but it can separate smaller particles too. Numerical results also suggest installing the air purifying system on the floor of the hospitals' room for maximum efficiency. [ABSTRACT FROM AUTHOR]

The industrialization, growing population, and human activities (e.g., liquid waste of households, industrial units, and agricultural lands) are the main causes to contaminate fresh water sources. To overcome this issue, many techniques have been applied for water purification and chemical oxidation is one of the effective ways to treat the wastewater called as advanced oxidation process (AOPs). In the present study, synthesized silver phosphate nanoparticles were employed as catalysts in the photocatalytic advanced oxidation process for the degradation of various dyes (RhB, MB, MO, and OG) and drug (SMZ). The photocatalyst was characterized through different analytical tools, e.g., PXRD, FTIR, UV-Vis DRS, DLS, FESEM, and HRTEM. The chemical behavior or interaction of dye molecule with catalyst surface has also been explored to understand the mechanism of photodegradation reaction. All the organic dyes and drugs showed pseudo first-order rate kinetics and it was found that RhB dye and SMZ drug degraded so fast by the photocatalyst. The maximum observed photodegradation rate was 0.0744 min−1 for SMZ drug and 0.0532 min−1 for RhB dye, respectively. The minimum dye degradation was observed ~ 0.0036 min−1 for OG, which is ~ 15 times lesser than the degradation rate of RhB dye. From the comparative dye degradation study, it was found that the photodegradation efficiency of organic pollutants depends on the surface charge of the photocatalyst. The role of photogenerated reactive species (holes, superoxides, and hydroxyl free radicals) was also studied using different types of scavengers which helped to understand the photochemical reactions and mechanism by photocatalyst. The real sample analysis of textile effluent was also performed using the best photocatalyst in the presence of light. [ABSTRACT FROM AUTHOR]

Diabetes is a worldwide disease in perpetual expansion. Type 1 and sometimes type 2 diabetic patients require daily human insulin (HI) or analog administration. Easy access to insulins for insulin-treated diabetics, their relatives, and medical professionals can enable abuse for suicidal or homicidal purpose. However, demonstrating insulin overdose in postmortem blood is challenging. Tissue analyses are contributive, as insulins can accumulate before death or undergo only limited degradation. The present study describes an assay for HI and synthetic analogs (lispro, aspart, glulisine, detemir and degludec, glargine and its main metabolite (M1)) in liver, kidney, muscle, and injection site samples. It is based on a 5-step sample preparation (reduction of tissue sample size, homogenization, extraction, concentration, and immunopurification) associated with liquid chromatography coupled to high-resolution mass spectrometry (LC–MS/HRMS). Selectivity and limit of detection (LOD) for all target analogs were assessed in the above matrices. LOD was determined at 25 ng/g for HI and for analogs except detemir and degludec, where LOD was 50 ng/g in kidney and injection site samples and 80 ng/g in the liver and muscle. The method was applied to13 forensic cases in which insulin use was suspected. [ABSTRACT FROM AUTHOR]

Japanese encephalitis is a vector borne disease and the best procedure for control of this disease is control of vector population. Now a day use of phyto-chemicals more preferred over use of chemical insecticides. Isolation, purification and determination of chemical structures of bioactive compounds were done successfully from n-hexane extract of leaf of M. ferrea. The compounds shows better potentiality to control Cx. vishnui 3rd instars larvae. n-hexane extract of leaf of M. ferrea was prepared by Sohxlet apparatus and further used for bioassay against 3rd instars larvae of Cx. vishnui. n-hexane extract was further fractioned by Thin layer chromatography to isolate bioactive compounds. From different band of TLC, bioactive compounds bearing band was isolated by bioassay test. Structures of active principles were determined by FTIR, gas chromatography, mass spectrometry and with the help of library data list. Cent percent mortality of Cx. vishnui larvae was recorded at 45 ppm concentration of n-hexane extract of M. ferrea after 72 h of exposure. In isolated bioactive compounds 3-(2-Hydroxyphenoxy)-1, 2-propanediol is one of predominant compound, may be responsible for mortality of Cx. vishnui larvae. LC50 value for Cx. vishnui 3rd instars larvae of active compound are 26.76, 25.64 and 20.32 ppm for 24 h, 48 h and 72 h respectively. No mortality were recorded when sub lethal concentration (LC50) of 24 h of bioactive compound applied on non-target organisms i.e. Chironomus circumdatus, Daphnia, Diplonychus etc. The compound i.e. 3-(2-Hydroxyphenoxy)-1, 2-propanediol is predominant compound of active principles and its chemical structure is determine which is major component of n-hexane extract of leaf of M. ferrea. These bioactive principles are safe for other organisms (non-target) those share the same natural habitat. [ABSTRACT FROM AUTHOR]

The catalytic activity of hexagonal boron nitride (hBN) is not yet well understood, but it seems to be related to hBN hydroxylated sites. A good understanding of those sites and how they are produced is a key step to reveal the true nature of hBN catalytic activity. Here, we report a set of thermal treatments to produce a diversity of hydroxylated sites, as well as a method to remove the boric acid produced by hBN decomposition. We found that some of the boric acid dehydrates on the surface of hBN to produce a borated hBN (hBNO) characterized by an FTIR peat at 1090 cm−1 and an XRD shift due to the variation in the planar distance. We also showed that when characterizing the thermal treated hBN, the storage of the sample changed the borate's hydration degree and modified both the XRD pattern and the FTIR spectrum. When stored in a humid environment, boric acid peaks are visible, but they are not present if samples are stored in a dry place. The methods established here are a solid basis for the manufacture, purification and characterization of hBN by thermal treatments, showing how the process can be designed to generate various functional groups on its surface. [ABSTRACT FROM AUTHOR]

This work presents the combination of two chemical separation methods to purify protactinium (Pa) oxide from its decay daughter chain. It combines precipitation and basic to neutral washing with ion exchange to reach radiochemical pure 231Pa. The method is suitable to purify 231Pa in milligram scales. Precipitation and washing of Pa hydroxide removes most of the daughter activity and the dose rate. Losses of Pa occurs predominantly in the precipitation stage and are dependent on the conditions used. The subsequent ion exchange procedure showed essentially no losses of Pa and is efficient to fully remove all decay products leaving less than 0.4% of the Th as an impurity in the purified Pa solution. Full radiochemical purity was obtained by repeating the separation procedure. The radiochemical pure Pa solution was characterised by an alpha ratio method by addition and mixing of a known Cm spike. The specific activity and concentration of 231Pa was determined with an uncertainty of 1% (coverage factor k = 1). [ABSTRACT FROM AUTHOR]

Photocatalysts are environmentally friendly materials that can be used to degrade vehicle exhaust. CeO2–Bi2O3 loaded on white carbon and tourmaline, as the favorable absorption materials, was prepared respectively for vehicle exhaust photocatalytic purification. Brunauer-Emmett-Teller (BET) adsorption isotherm, scanning electron microscope (SEM), Fourier transform infrared (FTIR), X-ray diffraction (XRD), transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS) were applied to characterize the composite materials. The optimum contents of the loading materials were obtained from the comparison of purification efficiency of vehicle exhaust components after a 60-min photocatalytic reaction under visible and ultraviolet (UV) irradiation, including hydrocarbons (HC), carbon monoxide (CO), carbon dioxide (CO2), and nitrogen oxides (NOx). The results show that the proposed preparation method could improve particle dispersion and distribution uniformity, reduce particle agglomeration, and increase specific surface area. The optical response range of the CeO2–Bi2O3 with loading materials can be extended from UV light to visible light. CeO2–Bi2O3 loaded on tourmaline show excellent photocatalytic purification effect under visible light. The purification efficiency of CeO2–Bi2O3 loaded on tourmaline for HC, CO, CO2, and NOx were 30.8%, 30.6%, 35.3%, and 47.6%, respectively. Moreover, the concentrations of vehicle exhaust components decrease with time, which is well fitted by the Langmuir-Hinshelwood pseudo-first-order kinetics model, and the purification rate constant of CeO2–Bi2O3 composites under visible light is greater than that under UV light. The prepared photocatalytic materials also exhibit the excellent reusability. [ABSTRACT FROM AUTHOR]

Adzuki bean is high in 5′-phosphodiesterase (5′-PDE), an enzyme that can form flavor enhancing 5′-nucleotides. In this work, 5′-PDE from adzuki bean is purified. Acetone precipitation (1 crude extract:1.25 cold acetone) is used as the first purification step as it is commonly used in enzyme purification to reduce unwanted proteins, before advancing into an application of the Fast Protein Liquid Chromatography system (FPLC). Three major techniques of purification were carried out in sequence as follows: desalting (using a Hi Prep 26/10 desalting column), anion exchange chromatography (using a Hi-Trap DEAE Fast Flow column), and gel filtration chromatography (using a Superose 12 10/300 GL column). The purification protocol adopted yielded 13.37% 5′-PDE with a purification fold of 6.7 and specific activity of 35.2 µmol p-nitrophenol/min/mg protein. The molecular weight of adzuki bean 5′-PDE was estimated using gel filtration chromatography by comparing the fraction that contained the highest 5′-PDE activity with the molecular weights of standard proteins (1.35–669 kDa). Native PAGE was conducted to determine the homogeneity of proteins in the gel filtration fraction showed one band. SDS-PAGE analysis indicated that the enzyme was composed of two identical polypeptide chains (subunits), each with a molecular weight of 62 kDa. Therefore, the estimated molecular weight of the native protein using SDS-PAGE was 124 kDa. [ABSTRACT FROM AUTHOR]

The methods used in the nuclear industry for reprocessing liquid radwaste, including salt concentrates from evaporator plants at nuclear power plants, are discussed. The results of a technical-and-economic feasibility study of the three methods used for the processing of salt concentrates are presented: cementing, deep evaporation, and ion-selective purification. It is shown that the ion-selective purification method is the most effective one in comparison with the first two, as it effects significant volume reduction of mid-level class-3 radioactive waste transferred for disposal. Recommendations are made for changing the technology used for management of liquid waste at next-generation nuclear power plants, including separate collection and creation of local schemes for their processing and conditioning. [ABSTRACT FROM AUTHOR]

Asrij/OCIAD1 is a scaffold transmembrane protein belonging to the Ovarian Carcinoma Immunoreactive Antigen Domain containing protein family. In Drosophila and mouse models, Asrij localizes at the endosomal and mitochondrial membrane and is shown to regulate the stemness of hematopoietic stem cells. Interaction of Asrij with ADP Ribosylation Factor 1 (Arf1) is shown to be crucial for hematopoietic niche function and prohemocyte maintenance. Here, we report the heterologous expression, standardization of detergents and purification methodologies for crystallization of Asrij/OCIAD1. To probe the activity of bacterially expressed Asrij, we developed a protein complementation assay and conclusively show that Asrij and Arf1 physically interact. Further, we find that sophorolipids improve the solubility and monodispersibility of Asrij. Hence, we propose that sophorolipids could be novel additives for stabilization of membrane proteins. To our knowledge, this is the first study detailing methodology for the production and crystallization of a heterologously expressed scaffold membrane protein and will be widely applicable to understand membrane protein structure and function. [ABSTRACT FROM AUTHOR]

Magnetorheological fluids have a viscosity which can be controlled by the application of magnetic field. Usually they have dispersions of magnetic particles with size micrometric in a carrier liquid. After purification process, extracted material from mining waste allowed us to obtain the magnetite that was used as the magnetic component of a magnetorheological fluid. The carrier continuous medium for such fluid was 2.5 and 20 W oils. These oils are used for damping systems in high-performance motorcycles and are readily available. The magnetics particle's size ranged from 2 to 100 µm. Magnetic fields from 50 to 1200 gauss, as well as structural, morphological, and rheological studies were performed to the analyzed fluids. We observed that the model that best fits the stress vs. shear rate curves was the Herschel–Bulkley model. [ABSTRACT FROM AUTHOR]

The meteorological data, measurements of aerosol optical depth (AOD) and PM2.5 concentration from 2016 to 2017 in Fuling District of Chongqing were selected to study their correlation. The back propagation (BP) artificial neural network (ANN) was used to build a PM2.5 prediction model with the meteorological factors as input, and the predicted PM2.5 values were compared with the measured ones. The results show that PM2.5 concentration has a piecewise linear relationship with temperature attributed to diffusion rate and premise conversion rate, a positive correlation with relative humidity, and a significant inverse correlation with wind speed, but no apparent linear relationship with rainfall, although rainfall has a significant purification effect on PM2.5. The similarity in the influence mechanism of AOD and PM2.5 concentration leads to a certain positive correlation between them. The predicted PM2.5 by the BP ANN model shows a similar trend with the measured one, but has some significant differences in numerical values. Therefore, it is feasible to establish BP artificial neural network to predict PM2.5 by using meteorological data. [ABSTRACT FROM AUTHOR]

The liquid–liquid extraction, recovery of Np(VI) and Np(V) from the solution of Na2CO3 by methyltrioctylammonium carbonate in toluene was investigated. By the graphic slope analyses method, as well as by recording of absorption spectra for obtained solutions and method of calculated determination of solution properties taking into account water activity, composition was established for the carbonate complexes of Np(VI) and Np(V) being extracted, which, depending on extraction conditions, can be expressed by the following formulae's: (R4N)2[NpVIO2(CO3)2], (R4N)3[NpVO2(CO3)2], (R4N)6[NpVIO2(CO3)4], (R4N)2[NpVIO2(CO3)2]·2(R4N)2CO3, (R4N)5[NpVO2(CO3)3], (R4N)7[NpVO2(CO3)4], (R4N)3[NpVO2(CO3)2]·(1–2)(R4N)2CO3, where R4N is the quaternary ammonium cation. The results have been obtained in the experiments, has much interest both in the field of alkaline radioactive waste management and with respect to their usage for extraction of transuranium elements during reprocessing of alkaline radioactive waste, as well as for liquid–liquid extraction purification of uranium and plutonium from admixtures of fission products. These techniques are used within the framework of a new alternative method for reprocessing of spent nuclear fuel in carbonate media the CARBEX (CARBonate EXtraction) process. [ABSTRACT FROM AUTHOR]

A radiochemical method was developed for the accurate 55Fe determination in various radioactive waste, in particular samples contaminated with 241Pu. It consisted of three purification steps based on first ammonium hydroxide precipitation, and then anion exchange separation followed by TRU®-based extraction chromatography. It was characterized by an iron recovery yield of about 80% for all the studied samples and a 60Co decontamination factor of 106. In comparison to a standard protocol based on iron cupferrate extraction in chloroform, an improvement of a 30-fold factor was achieved towards plutonium. The developed TRU®-based procedure was validated by participating in interlaboratory exercises. [ABSTRACT FROM AUTHOR]

The article presents the results of a research of the process of removing particles in range 2.5 µm that are most dangerous to human health using ultrasonic coagulation. The two-stage gas clearing system consisting of the agglomerator and the cyclone dust collector (supplemented by an ultrasonic radiator) was proposed and made. The carried out investigations have revealed the optimal conditions for the formation of a swirling flow, providing high efficiency coagulation of fine-dispersed particles. The formation of a swirling gas-dispersed flow in the conditions of ultrasonic exposure provides an increase in the average particle size 2.5 µm by 4.5 times due to particles convergence and the formation of local areas with high concentration. In this case, the ultrasonic effect on a rectilinear flow with 2.5-μm particles allows increasing particles size of only 1.6 times. The ultrasonic exposure has increasing 2.5-µm particle clearing efficiency from 46 to 85% by optimal conditions for gas-dispersed flow. [ABSTRACT FROM AUTHOR]

The increase of diesel vehicle leads to a large amount of NO emissions, and non-thermal plasma (NTP) combined with wood fiber is a new method in the field of exhaust gas purification. In this paper, the effects of NTP combined with different kinds of wood fibers and without wood fibers on the removal of NO were compared, and the optimal purification efficiency of NO was determined by experiments under different application conditions. The experimental results show that the NO conversion efficiency of NTP combined with wood fiber is better than that of NTP or wood fiber alone, among which NTP combined with scotch pine has the highest conversion efficiency. Through the analysis of the mechanism of NO conversion by wood and NTP, the effects of different conditions on NO conversion were obtained. The trend of NO removal with voltage/frequency indicates that the increase of voltage and frequency can promote the removal of NO. The increase of humidity also promoted the removal of NO, but when the humidity exceeded 25%, the conversion of NO decreased slightly. And the filling rate of 0.3 is the best value for NO conversion. Although NO cannot be completely purified by this method, there is still a higher conversion efficiency under the condition of low temperature and no catalyst. It can be proved that NTP bonded wood fiber is a new way to remove NO. [ABSTRACT FROM AUTHOR]

In the present study, commercial PES, PVDF, PTFE ultrafilter membranes, and two different nanomaterial (TiO2 and TiO2/CNT composite)-covered PVDF ultrafilter membranes (MWCO = 100 kDa) were used for the purification of an industrial oil-contaminated (produced) wastewater, with and without ozone pretreatment to compare the achievable fouling mitigations by the mentioned surface modifications and/or pre-ozonation. Fluxes, filtration resistances, foulings, and purification efficiencies were compared in detail. Pre-ozonation was able to reduce the total filtration resistance in all cases (up to 50%), independently from the membrane material. During the application of nanomaterial-modified membranes were by far the lowest filtration resistances measured, and in these cases, pre-ozonation resulted in a slight further reduction (11–13%) of the total filtration resistance. The oil removal efficiency was 83–91% in the case of commercial membranes and > 98% in the case of modified membranes. Moreover, the highest fluxes (301–362 L m−2 h−1) were also measured in the case of modified membranes. Overall, the utilization of nanomaterial-modified membranes was more beneficial than pre-ozonation, but with the combination of these methods, slightly higher fluxes, lower filtration resistances, and better antifouling properties were achieved; however, pre-ozonation slightly decreased the oil removal efficiency. [ABSTRACT FROM AUTHOR]

The stable isotope-labeled rosuvastatin was requested in order to fully understand the metabolic process of rosuvastatin. An effective synthesis approach was developed for [2H4] rosuvastatin calcium. After ten steps, [2H4] rosuvastatin calcium was prepared with excellent chemical purification and isotope enrichment which can be applied as an internal standard. Moreover, this synthesis method could be useful in synthesis of other statins. [ABSTRACT FROM AUTHOR]

Purification of nanoparticles is an important step during preparation of nanoparticles in order to remove impurities and excess ligands. Such excess ligands in the solution may have unfavorable effects on downstream processing such as ligand exchange and shell growth. Most purification methods are batchwise and time-consuming. In this work, we developed an extraction system with a membrane separation to continuously purify nanoparticles. Here, silver nanoparticles (AgNPs) in an aqueous solution were used as a case study. AgNPs were synthesized with sodium dodecyl sulfate (SDS) as capping ligands, and ethyl acetate was used as an extraction solvent to remove the ligands. This novel method showed more 56.73% removal of the ligands while maintaining the morphology of the AgNPs. In addition, the AgNPs from this method was compared with those from conventional methods such as precipitation-redissolution in terms of purity well as catalytic activity. The integration of flow synthesis of AgNPs and continuous-flow purification was also demonstrated. [ABSTRACT FROM AUTHOR]

The green microalga Haematococcus pluvialis has been widely studied due to its capacity to accumulate great amounts of astaxanthin, a high-value carotenoid with biological activities. In the present work, two green compressed fluid–based processes, pressurized liquid extraction (PLE) and supercritical antisolvent fractionation (SAF), are integrated to obtain an astaxanthin-enriched extract from this microalga. PLE was carried out using pressurized ethanol as solvent, for 20 min, at 10 MPa, and 50 °C as extraction temperature. Subsequently, the obtained extract was processed by SAF to further purify the carotenoid fraction. The SAF process was optimized using a 3-level factorial experimental design and considering three experimental variables: (i) CO2 pressure (10–30 MPa), (ii) percentage of water in the PLE extract (20–50%), and (iii) PLE extract/supercritical-CO2 flow rate ratio (0.0125–0.05). Total carotenoid content was evaluated in both extracts and raffinates. Best results were obtained at 30 MPa, 0.05 feed/SC-CO2 mass flow rate, and 20% (v/v) of water in the feed solution, achieving values of 120.3 mg g−1 carotenoids in extract (in the SAF extract fraction), which were significantly higher than those obtained in the original PLE extract. In parallel, a new fast two-dimensional comprehensive liquid chromatography (LC×LC) method was optimized to get the full carotenoid profile of these extracts in less than 25 min. This is the first time that the use of a C30 column is reported in an on-line LC×LC system. [ABSTRACT FROM AUTHOR]

Impurities are of crucial interest in optoelectronic devices as they affect carrier lifetimes and electrical properties. In view of that, it is important to incorporate certain processing steps to reduce impurities effect on final devices. The aim of this work is to enhance silicon carbide SiC purity for silicon passivation. Low cost method of SiC purification is presented. This method combines three main steps consisting of formation of porous silicon carbide layers by acid vapor etching followed by a photo-thermal annealing at different temperatures. Finally, obtained SiC powder was subject to a chemical treatment to remove porous SiC layer. Effect of gettering temperature on purification efficiency was evaluated by inductively coupled plasma atomic emission spectrometry (ICP-AES). The gettering experiment was performed at 800–950 °C, and optimum results were obtained at 950 °C. SiC purity is improved from 3 N (99.977%) to 5 N (99.999%) with an impurity removal efficiency of 96.56%. Purified SiC was used as a target to synthesize SiC layers using pulsed laser deposition technique (PLD) for optoelectronic devices. The use of intrinsic amorphous silicon carbide (a-SiC) passivating layers was investigated especially by photoconductivity decay technique. Improved SiC target purity leads to a significant enhancement of a-SiC passivating properties attributed to the surface recombination velocity decrease. Electrical properties of a-SiC/c-Si(p) were also studied using I-V and C-V techniques. [ABSTRACT FROM AUTHOR]

Cellulose nanowhiskers (CNWs) are appealing natural materials with a broad range of applications in nanoscience. The hydrolysis of the amorphous regions is a kinetic-controlled process in which the natural fibers undergo degradation at strong acidic conditions. Therefore, as-prepared samples of CNWs are constituted of particles with broad varieties of length and diameter. In fact, the majority of cellulose particles are microcrystalline. For more precise and specific applications, a further purification process of as-synthesized CNWs is required. This purification process must lead to more uniform nanoparticles. Herein, we report a purification protocol based exclusively on successive centrifugation steps. Cotton fibers were used as a cellulose source and the four-step centrifugation protocol applied for purification. Dynamic light scattering and transmission electron microscope techniques were used to verify the changes in the selection process. The initial sample was composed of particles between 50 and 2000 nm. After the four-step purification process, more than 90% of purified particles size ranged from 150 to 400 nm with a net yield of 54%. [ABSTRACT FROM AUTHOR]

This work presents the synthesis of a new nano-structured samarium ion-imprinted polymer (Sm(III)-IIP) by precipitation polymerization. The Sm(III)-IIP nanoparticles were prepared by the copolymerization of Sm(III)–acrylic acid–4-vinylpyridine ternary complex with ethylene glycol dimethacrylate and methyl methacrylate, and then, Sm(III) was leached to obtain Sm(III)-IIP leached particles. Moreover, non-imprinted polymer particles were similarly prepared without Sm(III) ions. The characterization of polymers was carried out by Fourier transform IR spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis–differential scanning calorimetry (TGA–DSC) and surface analysis. The effect of several parameters such as solution's pH, sorption and desorption time, type, concentration and volume of eluent on the extraction of the polymers was investigated and optimized by one variable at the time. Optimized parameters were as follows: pH 4; mass sorbent 0.1 g; sorption time, 120 min; desorption time, 120 min; aqueous phase volume, 10 mL. Moreover, it is found that 30 mL of HCl (3 M) provided the most effective elution of Sm3+ ion from IIP beads. The maximum sorbent capacity of the IIPs is 14.91 mg g−1. The sorbent was used for purification of samarium-152 stable isotope. The samarium-152 stable isotope recovery yield was % 99.67. The detection limit of the method was evaluated to be 0.27 ng mL−1. The precision of the method (%RSD, n = 6) was % 0.47. [ABSTRACT FROM AUTHOR]

Alkali metal chlorides emitted from sintering flue gas are easily adsorbed on the surface of activated carbon (AC) in the purification process. In this paper, NaCl particles adsorbing onto AC were simulated by impregnation method, and the size and morphology of NaCl particles were similar to those of NaCl-PM10 emitted from sintering flue gas. With the adsorption of NaCl particles, 2–10-μm pores of AC were filled, and the specific surface area of AC decreased. But NaCl led to the increase of acidic functional groups on the surface of AC. When 0.75 wt% NaCl was adsorbed, it was beneficial for AC catalytic denitration (de-NOx), because the chemical reaction was strengthened by acidic functional groups, so it showed a certain promotion of de-NOx efficiency. As 1.5 wt% NaCl and 3 wt% NaCl were adsorbed, NaCl had an inhibitory effect on AC de-NOx, which was because the specific surface area of AC decreased, and the prevention of physical adsorption played a major role. As a result, the de-NOx efficiency of AC adsorbed with 3 wt% NaCl decreased from 40.59 to 23.02% at 150 °C. Therefore, the absorption of NaCl fine particles on AC should not exceed 0.75 wt%. [ABSTRACT FROM AUTHOR]

Due to widespread droughts and population increase, the rapid and sustainable purification of contaminated water is of major interest to human beings. Toward this end, this paper reports a handheld and efficient purification system using maskless micro/nanofabrication techniques. A porous polymer membrane decorated with nanomaterials was tailored to physically filter pollutants in contaminated water. To create the porous polymer membrane, curable polymer and black sugar powder were used for a facile and cost-effective fabrication method. The black sugar particles linked in cured polymer were selectively dissolved in hot water, forming micro-sized pores for filtering out pollutants. The nanowires were hydrothermally grown onto the porous membrane to further improve the purification performance by capturing finer pollutants between nanowires. The combination of nanowires and 50-wt% concentration of black sugar particle, forming a porosity of ~ 27.71% showed the minimum residual rate (i.e., weight of pollutants in purified water) of 0.981 mg/ml. This study supports the use of hierarchical porous membrane for the efficient and sustainable purification of contaminated water within a short period time. [ABSTRACT FROM AUTHOR]

A CO oxidation catalyst that includes Pt clusters applied on nanosized TiN supports with a particle size of 18 and 36 nm has been synthesized. The catalyst has been studied using TEM, X-ray powder diffraction, and XPS methods. It has been found that platinum clusters formed on the support surface are covered with a mixture of platinum and platinum oxide. The coherent scattering range of the Pt cluster is close to 8 nm on a support with titanium nitride particles of 18 nm. The catalytic properties in the reaction of CO oxidation at 295 K and low CO concentrations (<100 mg/m3) have been examined. It has been found that when the platinum content in the catalyst is 9 to 15 wt %, the CO oxidation rate is 120 times higher than that on platinum black with a specific surface area of 30 m2/g. The catalysts are promising for use in catalytic systems for air purification. [ABSTRACT FROM AUTHOR]

Supercritical fluid extraction (SFE) using cosolvent-modified supercritical carbon dioxide and a two-step separation/purification method was investigated as a way to improve the purity of glabridin, one of the many bioactive components of Glycyrrhiza glabra (licorice). The SFE parameters were optimized using an analytical-scale SFE system in the temperature range 40–80°C and the pressure range 10–50 MPa. The extraction was then scaled up by 100 times using a preparative SFE system under the following set of optimized conditions: 40°C, 30 MPa, and SCCO2 modified with ethanol equivalent to its 25% (v/v) concentration. The glabridin purity obtained through the scaled-up SFE system was 6.2%, a much higher level than that obtained through organic solvent extraction. The licorice extract obtained by scaling up the SFE system was isolated and purified by applying alcohol precipitation/ filtration and adsorption chromatography with 80% aqueous ethanol to obtain a purer product. It was confirmed that the glabridin purity of the final extract product was increased by up to 37%, without significant loss of glabridin after two separation/purification steps. [ABSTRACT FROM AUTHOR]

Methods for the preparation of raw materials to produce leucosapphire are considered. It is shown that the main directions in the production of high-purity aluminum oxide raw materials are: electrochemical oxidation of aluminum, decomposition of alkoxides, high-temperature treatment of aluminum oxide in a halogen-containing atmosphere, and preliminary purification of aluminum-containing compounds followed by their decomposition. It is shown that methods of the purification of aluminum hydroxide and oxide obtained by the Bayer process are the most promising for industrial use. These methods include the complex purification and simultaneous preparation of ceramic preforms starting from aluminum hydroxides or oxides by their treatment in subcritical or supercritical steam and the following heat treatment in a halogen-containing medium. [ABSTRACT FROM AUTHOR]

We developed a sample preparation method for the determination of polybrominated diphenyl ethers (PBDEs) with from one to ten bromine atoms in samples of feed and food products containing approximately 0.5 g of animal fat or vegetable oil. The method involves gas chromatography with high-resolution mass spectrometry or tandem mass spectrometry. A possibility of using various reagents for the purification of extracts by chemical reactions and fractionation is studied. The physicochemical properties of PBDEs and polychlorinated biphenyls (PCBs) have significant differences, and to determine the full range of PBDEs, it is necessary to use other methods of sample preparation than in the case of PCBs. The conditions selected for the purification of extracts in a column filled with potassium silicate, Florisil, and silica impregnated with sulfuric acid and for their fractionation using activated neutral alumina ensure the PBDE recoveries of at least 75%. Purification of the extracts can be carried out without the use of chlorinated organic solvents. Applied aspects of instrumental analysis and measurement quality assurance are also described. [ABSTRACT FROM AUTHOR]

A promising method was proposed for the first time for purification of animal bone tissue fragments from high-molecular weight compounds in biphase media containing high-pressure CO2 (solutions of carbonic and peroxycarbonic acids). The efficiency of this purification was confirmed by SEM and IR spectroscopy. It turned out that, during the exposure of bone fragments in solutions of carbonic and peroxycarbonic acids at high CO2 pressure, mineral phase components of bone tissue are also extracted, which can be used to obtain highly dispersed hydroxyapatite particles upon extract reprecipitation. The structure and composition of the extracts were investigated by X-ray diffraction and scanning electron microscopy (SEM). [ABSTRACT FROM AUTHOR]

A promising method was proposed for the first time for purification of animal bone tissue fragments from high-molecular weight compounds in biphase media containing high-pressure CO2 (solutions of carbonic and peroxycarbonic acids). The efficiency of this purification was confirmed by SEM and IR spectroscopy. It turned out that, during the exposure of bone fragments in solutions of carbonic and peroxycarbonic acids at high CO2 pressure, mineral phase components of bone tissue are also extracted, which can be used to obtain highly dispersed hydroxyapatite particles upon extract reprecipitation. The structure and composition of the extracts were investigated by X-ray diffraction and scanning electron microscopy (SEM). [ABSTRACT FROM AUTHOR]

An efficient one-pot procedure has been proposed for the synthesis of 8-methyl-5-[(methylsulfanyl) methyl]-3-thiabicyclo[3.3.1]non-7-en-6-one from accessible natural raw materials. A stable complex of the title compound with gold(III) has been obtained by the extraction method, and the mode of its coordination to the metal ion has been determined by IR and NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Purification of berkelium-249 (249Bk) at Oak Ridge National Laboratory requires a multi-step process with Bk Finishing as the final step. The current multi-process takes 6-7 months, including ~ 3 months spent on Bk Finishing. Recent trials of using columns of either LN resin or MP-1 anion exchange resin adsorbing the tetravalent 249Bk4+ in 8M HNO3-0.5M NaBrO3, followed by eluting impurities (e.g. Ce4+, Cf3+) and stripping 249Bk resulted in a new dual column method of selectively separating 249Bk from other trans-curium elements and fission product impurities, which is proposed to replace the current Bk Finishing with higher Bk purification efficiency and shorter processing period. This paper displays the experimental results and describes the dual column method with relevant chemistry issues. [ABSTRACT FROM AUTHOR]

The fraction of hydrophobic peptides was eluted with MeCN (70%) in trifluoroacetic acid (TFA) solution (0.05%). The antibacterial activity of the culture fluid (Table 1) and intermediate fractions in each purification step was determined by spotting on agar and estimating the diameter of the indicator culture growth inhibition zone [[6]]. Extension of tryptic fragment sequences of bacteriocin Mal from Lactobacillus plantarum strain Mal and known orthologs from similar strains. [Extracted from the article]

Saccharomyces boulardii was used for antimicrobial peptides production. Separation process of produced antimicrobial peptides was conducted using ultrafiltration technique through dialysis membranes with porous 10 (MWCO) kDa. The inhibition activity was determined against four bacterial isolates. As a result, higher inhibition zone against Bacillus cereus were 26, 29 and 33 mm after adding 50, 75 and 100 µL of concentrated peptide, respectively. After that, peptide passed through the Sephadex G-50 column to achieve purified peptide using gel filtration. The high activity of purified peptide was confirmed based on the second peak reaching to 37 mm of bacterial inhibition zone while other peaks did not show any inhibition against tested bacteria. Some of the important characteristics of purified bioactive peptide were applied. Antimicrobial peptides stability was studied and found to be stable at pH range from 5 to 7 values studied in addition to its inhibition activity reached to 100%. Regarding thermal stability, it was observed that the peptide was fully activity at a both 60-80 °C for 30 min. Moreover, molecular weight of a peptide was identified using electrophoresis technique with SDS measured at 5792 Dalton. [ABSTRACT FROM AUTHOR]

The ability of Baculoviruses to hyper-express very late genes as polyhedrin, the major component of occlusion bodies (OBs) or polyhedra, has allowed the evolution of a system of great utility for biotechnology. The main function of polyhedra in nature is to protect Baculovirus in the environment. The possibility of incorporating foreign proteins into the crystal by fusing them to polyhedrin (POLH) opened novel potential biotechnological uses. In this review, we summarize different applications of Baculovirus chimeric OBs. Basically, the improvement of protein expression and purification with POLH as a fusion partner; the use of recombinant polyhedra as immunogens and antigens, and the incorporation of proteins into polyhedra to improve Baculoviruses as bioinsecticides. The results obtained in each area and the future trends in these topics are also discussed. [ABSTRACT FROM AUTHOR]

Modern technological approaches to ensuring the specific safety of human immunoglobulin and albumin preparations are analyzed. Introduction into human immunoglobulin preparation technology of donor screening for group- and rhesus-affiliations and chromatographic purification steps to reduce the contents of anti-A and anti-B hemagglutinins and anti-D antibodies are shown to be promising. Technological capabilities for reducing the anticomplementary activity and thrombogenic potential of immunoglobulin preparations and decreasing the contents of prekallikrein activator in human i.v. immunoglobulin and albumin preparations are discussed. [ABSTRACT FROM AUTHOR]

Pancreatic lipase inhibitors, such as tetrahydrolipstatin (orlistat), are used in anti-obesity treatments. Orlistat is the only anti-obesity drug approved by the European Medicines Agency (EMA). The drug is synthesized by saturation of lipstatin, a β-lactone compound, isolated from Streptomyces toxytricini and S. virginiae. To identify producers of novel pancreatic lipase inhibitors or microbial strains with improved lipstatin production and higher chemical purity remains still a priority. In this study, a high-throughput screening method to identify Streptomyces strains producing potent pancreatic lipase inhibitors was established. The assay was optimized and validated using S. toxytricini NRRL 15443 and its mutants. Strains grew in 24-well titer plates. Lipstatin levels were assessed directly in culture medium at the end of cultivation by monitoring lipolytic activity in the presence of a chromogenic substrate, 1,2-Di-O-lauryl-rac-glycero-3-glutaric acid 6-methylresorufin ester (DGGR). The lipase activity decreased in response to lipstatin production, and this was demonstrated by accumulation of red-purple methylresorufin, a product of DGGR digestion. The sensitivity of the assay was achieved by adding a lipase of high lipolytic activity and sensitivity to lipstatin to the reaction mixture. In the assay, the fungal lipase from Mucor javanicus was used as an alternative to the human pancreatic lipase. Many fungal lipases preserve high lipolytic activity in extreme conditions and are not colipase dependent. The assay proved to be reliable in differentiation of strains with high and low lipstatin productivity. [ABSTRACT FROM AUTHOR]

The ability of cobalt-, iron-, and zinc-containing framework compounds to take up impurities (free fatty acids and peroxide compounds) from linseed, false fl ax, and sunfl ower oil was studied. These framework structures improve the physicochemical properties and quality of the vegetable oils tested. The metal-organic frameworks surpass in performance the traditionally used industrial and natural sorbents. The sorbents tested preserve the performance for no less than five cycles. [ABSTRACT FROM AUTHOR]

A new two-step procedure has been developed for the synthesis of 2,2′: 6′,2″-terpyridine and 4′-methylsulfanyl-2,2′: 6′,2″-terpyridine in more than 70% yield on the basis of Potts’ condensation. Efficient methods have been proposed for purification of all condensation products. [ABSTRACT FROM AUTHOR]

Purpose: The emulsifiers in an exceedingly higher level are used in the preparation of drug loaded polymeric nanoparticles prepared by emulsification solvent evaporation method. This creates great problem to the formulator due to their serious toxicities when it is to be administered by parenteral route. The final product is therefore required to be freed from the used surfactants by the conventional purification techniques which is a cumbersome job. Methods: The solvent resistant stirred cell ultrafiltration unit (Millipore) was used in this study using polyethersulfone ultrafiltration membrane (Biomax®) having pore size of NMWL 300 KDa as the membrane filter. The purification efficiency of this technique was compared with the conventional centrifugation technique. Results: The flow rate of ultrafiltration was optimized for removal of surfactant (polyvinyl alcohol) impurities to the acceptable levels in 1-3.5 h from the nanoparticle dispersion of tamoxifen prepared by emulsification solvent evaporation method. Conclusions: The present investigations demonstrate the application of solvent resistant stirred cell ultrafiltration technique for removal of toxic impurities of surfactant (PVA) from the polymeric drug nanoparticles (tamoxifen) prepared by emulsification solvent evaporation method. This technique offers added benefit of producing more concentrated nanoparticles dispersion without causing significant particle size growth which is observed in other purification techniques, e.g., centrifugation and ultracentrifugation. [ABSTRACT FROM AUTHOR]

The vast majority of Hg can be removed while elemental mercury (Hg) can hardly be removed due to its characteristic of high volatility and insolubility in water. Till now, how to oxidize Hg to Hg is the key for the purification of Hg, especially when there are others pollutants, such as HCl, SO, and NOx. In this review, the method and mechanism of Hg purification from flue gas by HO, KMnO, NaClO, and O are reviewed comprehensively. It is concluded that the oxidation of Hg mainly depends on the electronic supply efficiency from the solution. The Fenton reagent, composed of HO and metal cations, is superior to O and the solution of KMnO and NaClO. Moreover, HCl, SO, and NOx in the flue gas can influence the oxidation and purification mechanism of Hg. It is found that HCl in flue gas had obvious auxo-action on the oxidation of mercury, and SO and NOx have different effects on the oxidation of Hg with the change of compositions and concentration of pollutants in the flue gas. In general, SO and NOx can slightly promote the oxidation of Hg due to the synergistic effect. [ABSTRACT FROM AUTHOR]