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Citronellyl acetate is a crucial component of flavor and fragrance in the food, cosmetic, and pharmaceutical sectors. In non-aqueous media, it can be successfully produced via lipase catalysis. This study focuses on the lipase-catalyzed trans-esterification of citronellol alcohol with geranyl acetate ester in a non-aqueous medium to produce citronellyl acetate. For the synthesis of citronellyl acetate, crude acetone powders isolated from several plant seedlings of black cumin, fenugreek, coriander, flax, and rape seed were examined for lipase activity. Black cumin seedling lipase had the highest level of citronella acetate production with a yield of 76.32% in 72 h of reaction time. To assess the impact of different reaction parameters on citronellyl acetate production in organic solvents, hexane was chosen as the best solvent, and black cumin seedling lipase was selected as the best biocatalyst. The highest conversion yield of ester (76.32%) was found when 0.25 M of geraniol acetate and 0.25 M of citronellol reacted at 41 oC after 72 h in the presence of 0.25 g of seedling lipase enzyme in n-hexane. It has been determined that crude black cumin seedling lipase is inexpensive yet effective and has the potential to be used industrially for the synthesis of terpene esters.

The multi‐10.000 tons scale manufactured chemical ε‐caprolactone attracts high industrial interest due to its favorable biodegradability properties. However, besides being of petrochemical origin yet, its production has a conceptual limitation that is the difficult extraction of this highly water‐soluble monomer from the water phase resulting from the aqueous solution of H2O2 applied as reagent. In this contribution, we report a chemoenzymatic cascade starting from bio‐based phenol, which makes use of O2 instead of H2O2 and runs in pure organic medium, thus requiring only simply decantation and distillation as work‐up. In a first step, phenol is hydrogenated quantitatively to cyclohexanol under solvent‐free conditions with a Ru‐catalyst. After simple removal of the heterogenous catalyst, cyclohexanol is converted to ε‐caprolactone in a biocatalytic double oxidation with very high yields just requiring O2 as reagent. This biocatalytic process proceeds in pure organic medium, thus avoiding tedious extraction to isolate the highly water‐soluble ε‐caprolactone and enabling a substantially simplified work‐up by only centrifugal separation of lyophilized whole cells and solvent removal. This oxidation is accomplished using a tailor‐made recombinant whole‐cell catalyst containing an alcohol dehydrogenase and a cyclohexanone monooxygenase mutant. [ABSTRACT FROM AUTHOR]

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Despite their widespread applications in sectors such as pulp and paper, textile, food and beverage, pharmaceuticals, and biofuel production, laccases encounter challenges related to their activity and stability under varying reaction conditions. This review accumulates data on the complex interplay between laccase characteristics and reaction conditions for maximizing their efficacy in diverse biotechnological processes. Benefits of organic media such as improved substrate selectivity and reaction control, and their risks such as enzyme denaturation and reduced activity are reported. Additionally, the effect of reaction conditions such as pH and temperature on laccase activity and stability are gathered and reported. Sources like Bacillus pumilus, Alcaligenes faecalis, Bacillus clausii, and Bacillus tequilensis SN4 are producing laccases that are both thermo-active and alkali-active. Additionally, changes induced by the presence of various substances within reaction media such as metals, inhibitors, and organic solvents are also reported. Bacillus pumilus and Bacillus licheniformis LS04 produce the most resistant laccases in this case. Finally, the remarkable laccases have been highlighted and the proper laccase source for each industrial application is suggested. [ABSTRACT FROM AUTHOR]

Reliable electrochemical measurements depend on the availability of robust reference electrodes (RE) with well-defined potentials. While many reliable REs are known, they are not applicable in certain demanding media such as ionic liquids, nor in small confined spaces. Here, we describe the fabrication of a simple yet robust Ag/Ag2S micro-reference electrode (μ-RE) where a micron-thick Ag2S layer is formed by isothermal reaction with sulfur vapor. Scanning electron microscopy, X-ray photoemission spectroscopy, and spectroscopic ellipsometry characterization reveals that the optimal morphology corresponds to a slightly porous Ag2S film. We demonstrate that the Ag/Ag2S μ-RE can be operated in and cycled through a wide variety of polar organic solvents, including common protic solvents (EtOH), aprotic solvents (ACN, DMSO, NMP, DMF) and ionic liquids (EMIM-TFSI, BMP-TFSI), with short equilibration time (tens of seconds) and little drift (

Organic Rankine cycles (ORC) are quite popular, but the overall efficiencies of these plants are rather very low. Numerous studies have been conducted in many scientific centers and research centers to improve the efficiency of such cycles. The research concerns both the modification of the cycle and the increase in the parameters of the medium at the inlet to the turbine. However, the efficiency of even these modified cycles rarely exceeds 20%. The plant modifications and the optimization of the working medium parameters, as a rule, lead to cycles with the high pressure and high temperature of live vapor and with a regenerator (heat exchanger) for the heating, vaporization and superheating of the medium. A new modified cycle with supercritical parameters of the working medium and with a new type of turbine has been described and calculated in the paper. For the first time, the isothermal turbine is proposed for supercritical organic cycles, though this solution is known as the Ericsson cycle for gas turbines. The innovative cycle and the usual ORC plants are characterized by almost identical block diagrams, while in the proposed cycle, the work of the turbine is obtained as a result of isothermal expansion and not in an adiabatic process. The analysis has been performed for 11 different working media and two cycles. The calculations have shown that power plants with isothermal expansion achieve better efficiency than cycles with adiabatic turbines. For example, the rise in efficiency changes from 8 percentage points for R245fa up to 10 percentage points for acetone. The calculations have proved that it is possible to obtain efficiency exceeding 50% for organic power plants. This is an outstanding result compared with modern steam and gas turbine units. [ABSTRACT FROM AUTHOR]

• Organic media (date-seeds, SCG and coco-coir) achieved maximum removal of organics. • Phosphate was best removed by bone, 40% higher than SCG, the next best material. • Zeolite provided markedly faster and higher removal of ammonium than other media. • Perlite was not a good option for integrated greywater treatment application. • SCG kinetics for organic removal were much more rapid than other media. Greywater recycling provides a means to address rising water demand with reduced environmental impact due to its abundance and lightly polluted nature. While many studies have examined high-tech treatment systems, these often require operator expertise and energy/chemical inputs that are not sustainable for a decentralised treatment process. Nature based systems such as green walls are emerging as alternatives. An effective plant support media is crucial to this treatment system and must be carefully chosen. This study compared the removal and kinetic performance of eight support media for nutrients and organic pollutants from synthetic greywater. The media were a mixture of organic and mineral materials, including waste-derived materials, and included: coco coir, spent coffee grounds (SCG), date seeds, SCG biochar, cattle bones, plastic carrier media, zeolite, and perlite. The best total organic carbon (TOC) removal was achieved by SCG biochar (50.7 %) and chemical oxygen demand removal (50.9 %) by zeolite. However, when accounting for leaching, which was significant in some organic media but expected to decrease with time, most organic media (SCG, date seeds, coco coir and bone) achieved around 80 % TOC removal. Of these materials SCG provided the most rapid removal. TOC and COD kinetics were best fitted by the pseudo-first-order model across all media except COD for SCG. The diffusion model plot indicates some diffusion-controlled process where sorbate concentration affects adsorption. COD elimination by SCG followed pseudo second order kinetics, suggesting chemisorption-dominated phenomena. The highest removal of phosphorus in greywater, after accounting for leaching, was achieved with cattle bone (88 ± 3.2 %), followed by SCG (55 ± 4.6 %). However, bone also had the highest phosphate leaching. Zeolite was the most effective in removing NH 4 +, achieving 82 ± 3.7 % removal. The dynamics of phosphate removal followed a pseudo-first order model for most media. Ammonia kinetics were best fitted by intra- particle diffusion and pseudo second order models. In summary, different media targeted different pollutants and a synergistic blend of these media holds the potential for efficient pollutant removal from greywater through nature-based processes. [ABSTRACT FROM AUTHOR]

Li was prepared by direct electrodeposition with N,N-dimethylformamide (DMF) as solvent and LiCl as raw material.The basic physicochemical properties of the binary DMF-LiCl system were studied, and the conductivity activation energy and viscous flow activation energy at different LiCl concentrations were calculated; The electrochemical characteristics of electrolyte systems with different LiCl concentrations were studied by cyclic voltammetry. The redox potential of Li (2.5 V and-2.9 V, vs.Ag/Ag+) and the optimal LiCl concentration (0.7 mol/L) were obtained; The lithium ions diffusion coefficient is calculated to be 2.6×10-8 cm²/s at the LiCl concentration of 0.7 mol/L.Using constant potential deposition, the metal lithium deposit with relatively dense grains in the lithium coating was successfully obtained on the high-purity tin cathode.The coating mainly contained metal lithium and Li-Sn alloy. [ABSTRACT FROM AUTHOR]

The analysis of published data on disproportionation reactions of actinides in aqueous solutions of acids, carbonates, and alkalis, in solutions of unsaturated heteropoly compounds, chelators, in organic media containing extractants was carried out. It is shown that the dependence on [H+] and the order by H+ are related to the difference in the standard potentials of the emerging and reacting ion pairs. The course of reactions is complicated by the formation of cation–cation complexes An(V)–An(VI) and others. The conditions are determined under which actinides in one or another oxidation state remain resistant to disproportionation. Among the unresolved issues, it should be noted the desirability of studying these reactions in solutions of fluorides, H3PO4, unsaturated heteropolycompounds, crown ethers, porphyrins, in the presence of extractants. [ABSTRACT FROM AUTHOR]

A kind of amino groups modified polyacrylonitrile fibers (PAN-A) was prepared to extract uranium from organic-containing low-level radioactive wastewater (OC-LLRW). SEM/EDS and FTIR characterization conformed that amino group was triumphant grafed on polyacrylonitrile fibers (PAN) surface. Its adsorption capacity was 492.1 mg g−1 (pH 6.0) and can endure at least five adsorption/desorption cycles under condition of 0.1 mol L−1 HCl solution. This PAN-A can work efficiently in the organic containing waste water (urea, tetrahydrofurfuryl alcohol), while the polyvinylalcohol (PVA) exhibited an apparently suppressive effect. This phenomenon was mainly with respect to the sticky nature of PVA. [ABSTRACT FROM AUTHOR]

This study reports four heavy metals, i.e., Zinc (Zn), Chromium (Cr), Nickel (Ni), and Lead (Pb) removal from landfill leachate employing two-hybrid subsurface flow constructed wetland systems; each system included a vertical flow (VF) followed by a horizontal flow (HF) wetland. The wetland systems were packed with organic (coco-peat) or construction (brick, sand) materials and planted with Phragmites australis or Chrysopogon zizanioides (Vetiver). Both systems were operated under without, and with effluent recirculation protocols. Cr, Ni, and Pb concentration were 2–73 mg/kg, 3–12 mg/kg, and 0.00004–27 mg/kg, respectively in Phragmites; 8–34 mg/kg, 3–15 mg/kg, and 0.00004–14 mg/kg, respectively in Vetiver. Organic carbon (C) and iron (Fe) of the coco-peat, brick allowed media-based metals removal in VF wetlands; such accumulation was not quantified in sand-based HF wetlands. Zn, Cr, Ni, Pb removal percentages increased between 75 and 98%, 29 and 41%, 14 and 48%, 23 and 26%, respectively, in VF wetlands during the effluent recirculation period (compared with removal performances of without recirculation phase). Removal percentages were reduced in HF wetlands during the recirculation period. Overall, Zn, Cr, Ni, Pb removal percentages in the two-hybrid wetlands ranged between 20 and 97%, 95 and 99%, 55 and 73%, 69 and 83%, respectively.

The soils in Samigaluh are mostly dominated by clay and used by farmer for crops production. The growing media for potted chrysanthemum requires additional organic media that could be mixed with the organic material to improve chemical and physical soil properties. Furthermore, the research location is a region with little water in dry season. The research aimed to determine the growth and flower yield response of Avanthe agrihorti to the different organic material mixed with clay and watering frequency. The research was arranged in a split plot design with 3 replications, conducted at an altitude of 462 m above sea level in the village of Gerbosari, Samigaluh, from March to June 2018. The main plot was watering frequency, i.e. every day, every three days and every five days. The subplot was types of media, i.e. clay + manure, clay + manure + cocopeat, clay + manure +rice husk, and clay + manure + rice husk charcoal. Data on the growth and yield of chrysanthemum plants were observed and statistically analyzed with ANOVA and continued with DMRT test at 5%. The results showed that the types of media and watering frequency did not significantly give different effect on most of the observed variables. However, Avanthe Agrihorti planted on clay + manure + cocopeat at all watering frequencies showed better growth and yield of flowers than those planted on other media. The efficient watering frequency for Avanthe Agrihorti was every three days. This study provides information for farmers on an alternative method to prepare the best media for the cultivation of potted chrysanthemum on the soil clay.

Many food, cosmetic and pharmaceutical industries have increased their interest in short-chain esters due to their flavor properties. From the industrial standpoint, enzyme reactions are the most economical strategy to reach green products with neither toxicity nor damage to human health. Isoamyl butyrate (pear flavor) was synthesized by isoamyl alcohol (a byproduct of alcohol production) and butyric acid with the use of the immobilized lipase Lipozyme TL IM and hexane as solvents. Reaction variables (temperature, butyric acid concentration, isoamyl alcohol:butyric acid molar ratio and enzyme concentration) were investigated in ester conversion (%), concentration (mol L-1) and productivity (mmol ester g-1 mixture . h), by applying a sequential strategy of the Fractional Factorial Design (FFD) and the Central Composite Rotatable Design (CCRD). High isoamyl butyrate conversion of 95.8% was achieved at 24 hours. At 3 hours, the highest isoamyl butyrate concentration (1.64 mol L-1) and productivity (0.19 mmol ester g-1 mixture . h) were obtained under different reaction conditions. Due to high specificity and selectivity of lipases, process parameters of this study and their interaction with the Lipozyme TL IM are fundamental to understand and optimize the system so as to achieve maximum yield to scale up. Results show that fusel oil may be recycled by the green chemistry process proposed by this study.

The paper deals with the research results on changes in antimicrobial activity of strain Streptomyces canosus CNMNAc-02 and its 3 variants (obtained using γ irradiation, combined (γ and UV) mutagenesis, low-frequency and low intensity magnetic field) after long-term storage (20 years) by subculturing. Antimicrobial activity was determined by the disk diffusion method, as test cultures were chosen opportunistic pathogenic bacteria and fungi which cause crop diseases. Analysis of the results obtained allow us to recommend oat agar medium for long-term storage of the original S. canosus CNMN-Ac-02 strain with antibacterial activity against phytopathogenic bacteria, and Czapek medium with glucose to preserve antifungal activity. For S. canosus CNMN-Ac-03, the antifungal activity is preserved on Gause medium, and for S. canosus CNMN-Ac-04 - on Czapek medium. For variant treated with magnetic field, higher antibacterial activity was registered against Clavibacter michiganensis 13a on Gause medium, by cca. 11.0 % more than original strain. Also it was noted, that strains synthesize several antibiotics, because of ability to inhibit develop both of phytopathogenic fungi and bacteria. [ABSTRACT FROM AUTHOR]

Olive, chiefly used for high quality edible oil and pickling, is a traditionally an important fruit crop of Mediterranean basin. Its cultivation has expanded to different parts of the world including Pakistan. The ability of olive to thrive on marginal and rocky lands has made it a popular fruit crop in Potohar. The present study was planned to investigate the impact of organic media and NPK levels on growth of olive seedlings. The research material consisted of 150 olive seedlings. The experiment was laid out following Complete Randomized Block Design with three replications at field area of Department of Horticulture, PMAS Arid Agriculture University Rawalpindi, Pakistan during 2018-19. There were 10 treatments of organic media and NPK doses with different combinations. Data were recorded for various traits viz., plant height, number of leaves and primary branches, leaf fresh weight, root length, root fresh weight, chlorophyll and NPK content. Data recorded were analyzed statistically using Statistix 8.1 software to ascertain significance and means were compared using LSD at 5% probability level. Results revealed that treatment T6 (FYM + Silt + Dose 3 i.e. 7.5 g NPK) was found most ideal growing media for most of traits like number of primary branches, root length, fresh root weight and chlorophyll content in olive seedlings. Hence it is recommended that growth media comprising of silt, FYM and 7.5 g NPK should be used for growing olive seedlings successfully. [ABSTRACT FROM AUTHOR]

Many food, cosmetic and pharmaceutical industries have increased their interest in shortchain esters due to their flavor properties. From the industrial standpoint, enzyme reactions are the most economical strategy to reach green products with neither toxicity nor damage to human health. Isoamyl butyrate (pear flavor) was synthesized by isoamyl alcohol (a byproduct of alcohol production) and butyric acid with the use of the immobilized lipase Lipozyme TL IM and hexane as solvents. Reaction variables (temperature, butyric acid concentration, isoamyl alcohol:butyric acid molar ratio and enzyme concentration) were investigated in ester conversion (%), concentration (mol L-1) and productivity (mmol ester g-1 mixture . h), by applying a sequential strategy of the Fractional Factorial Design (FFD) and the Central Composite Rotatable Design (CCRD). High isoamyl butyrate conversion of 95.8% was achieved at 24 hours. At 3 hours, the highest isoamyl butyrate concentration (1.64 mol L-1) and productivity (0.19 mmol ester g-1 mixture . h) were obtained under different reaction conditions. Due to high specificity and selectivity of lipases, process parameters of this study and their interaction with the Lipozyme TL IM are fundamental to understand and optimize the system so as to achieve maximum yield to scale up. Results show that fusel oil may be recycled by the green chemistry process proposed by this study. [ABSTRACT FROM AUTHOR]

The use of neat reaction media, that is the avoidance of additional solvents, is the simplest and the most efficient approach to follow in biocatalysis. Here, we show that unspecific peroxygenase from Agrocybe aegerita (AaeUPO) can hydroxylate the neat model substrate cyclohexane. H2O2 was photocatalytically generated in situ by nitrogen‐doped carbon nanodots (N−CNDs) and UV LED illumination. AaeUPO entrapment in alginate beads increased enzyme stability and facilitated the reaction in neat cyclohexane. N−CNDs absorption in beads containing AaeUPO created a 2‐in‐1 heterogeneous photobiocatalyst that was active for up to seven days under reaction conditions and produced cyclohexanol, 2.5 mM. To increase productivity, the bead size and the photocatalyst‐to‐enzyme ratio have been identified as promising targets for optimisation. [ABSTRACT FROM AUTHOR]

A major constraint in vertical flow constructed wetlands (VFCWs) while treating low carbon sewage is poor removal of nitrogen. Lack of carbon sources causes low denitrification. In this research, four pilot-scale VFCWs (R1, R2, R3 and R4) were constructed and filled with sand and gravel at the top and bottom portions, respectively. The middle portion was filled with organic media: R2 - wood mulch, R3 - paddy straw, R4 - coir pith, respectively. Wetland R1 acted as a control system and was filled with gravel in the middle. All the wetlands were planted with Canna indica and were intermittently loaded with synthetic wastewater at a retention time of 72 h. Ammoniacal nitrogen (NH4–N) removal efficiency of R1, R2, R3, R4 wetlands were 75%, 82%, 80% and 86%, respectively. Nitrate (NO3–N) removal efficiency of R1, R2, R3, R4 wetlands were 57%, 83%, 86% and 82%, respectively. The mass balance study of nitrogen showed that the nitrogen removal in vertical flow (VF) wetlands is mainly by plant uptake and nitrogen loss by gasification (nitrification and denitrification process). Scanning electron microscope (SEM) and energy dispersive analysis of the organic media confirms the carbon leaching in the organic media. [ABSTRACT FROM AUTHOR]

Organic soil amendments can be useful for improving degraded soil, but this increase in organic matter (OM) may influence adsorption of herbicides subsequently applied to the treated soil, even though the particle size of amendments and their nature differ from typical soil OM. In this study, a batch equilibrium method was used to measure adsorption of five herbicides following application to two organic media, wood pulp and sawdust, comparing these with two cropping soils. Herbicide adsorption, quantified by distribution coefficients (kd), was much higher in the two organic media than in the cropping soils. The increases in adsorption were strongly correlated to the percentage of organic carbon. When the kd was normalized to adsorption coefficients corrected for OM content (koc), variation in results between the media was greatly reduced, indicating that OM is an important factor influencing adsorption in these media. The results of this study suggest that herbicides will be less effective when applied to soils in which sawdust and wood pulp have been added. Using organic amendments to remediate soil will increase adsorption of pesticides, reducing their bio-availability and efficacy, but also reducing their tendency to leach into root zones of deep-rooted crops and into groundwater. [ABSTRACT FROM AUTHOR]

Studies were conducted on six pilot-scale vertical flow constructed wetland (VFCW) systems for the treatment of real domestic wastewater. All the six VFCWs had identical configurations and was filled with sand at the top and gravel at the bottom. The middle layer of each wetland system was filled with organic media (wood mulch, sugarcane bagasse and coir) and inorganic media (gravel, brick rubbles and pebbles), respectively. All the VFCWs were planted with wetland plant Typha latifolia. During the experimental study, the wetlands were loaded with real domestic wastewater. Performances of the wetlands were evaluated for the removal of organics, nutrients and bacterial contamination. The organic media wetlands had a removal efficiency of biochemical oxygen demand (BOD5) (75%-88%), chemical oxygen demand (COD) (72%-82%), ammonia nitrogen (NH4-N) (63%-70%), nitrate nitrogen (NO3-N) (77%-80%), total nitrogen (TN) (67%-68%) and total phosphorous (TP) (66%-80%). The control and inorganic media wetlands had a removal efficiency of BOD5 (91%-94%), COD (82%-85%), NH4-N (51%-77%), NO3-N (59%-63%), TN (42%-56%) and TP (58%-68%). Total suspended solids and fecal coliform removal was above 88% and 95%, respectively, in all the wetlands irrespective of the media. [ABSTRACT FROM AUTHOR]

The efficiencies of the Organic Rankine Cycle (ORC) are not very high and only very seldom do they exceed 20%. The increase and optimization of initial parameters and certain modifications of the thermodynamic cycle make it possible to overcome these drawbacks. A new modified cycle has been described and analyzed in detail in the paper. Similarly to the Ericsson cycle for gas turbines, isothermal expansion in the turbine is suggested for the power plant with organic media. The new cycle and the typical ORC power plants have the same block diagram. The only difference is that expansion in the proposed cycle occurs not adiabatically but as an isothermal process. The thermodynamic calculations have been carried out for 11 various fluids and 4 different cycles. The obtained results have clearly shown that cycles with isothermal expansion (isothermal turbines) are characterized by remarkably higher efficiency than typical power plants with adiabatic turbines. The increase in efficiency varies from 6 to 12 percent points for cycles with saturated live vapor and from 4 to 7 percent points for cycles with superheated live vapor. The performed analyses have shown that it is possible to achieve a very high efficiency (over 45%) of organic cycle, which is a very competitive value. In such cases the proposed power plants can achieve an efficiency which is higher than that of modern steam turbine plants with supercritical parameters.

Lead (Pb) and cadmium (Cd) are sources of serious problems in the environment due to their reactivity and toxicity. Lumbricus rubellus is an earthworm reared by people is expected to reduce Pb and Cd concentrations in the environments. The aim of this study was to explore the ability of Lumbricus rubellus in reducing excess of Pb and Cd in organic media generated from urban waste. Sixteen treatments (four levels of Pb concentration and four levels of Cd concentration) were arranged in a completely randomized design with three replications. Each treatment was placed in a wooden pot of 20 cm x 20 cm x 25 cm, and supplied with 40 Lumbricus rubellus for 30 days. Results of this study showed that 20 and 40% of the earthworm could survive until day 30 in organic media contaminated with Pb and Cd, respectively. Pb accumulated in the earthworm bodies ranged from 0.03 to 211.42 mg/kg, while the Cd accumulated in the earthworm body ranged from 0.57 to 22.11 mg/kg. The bioaccumulation factor for Pb was 46.98%, while that of Cd was 53.83%t. The content of Pb in vermicompost ranged from 0.04 to 19.41 mg/kg, while that of Cd ranged from 0.01 to 1.58 mg/kg.

Abstract Developing of high efficient electrode materials for CO 2 reduction is very important in CO 2 conversion and recycling utilization. In this work, we have fabricated ZnS/Zn electrode using sulphur infiltration method. This method is a well-developed technology in surface treatment. ZnS/Zn electrode fabricated via sulphur infiltration method has a crucial advantage: because sulfur atomic is infiltrated into Zn substrate, a translation layer is formed and sandwiches between ZnS layer and Zn substrate. As a result, ZnS connects with Zn substrate firmly, and the exfoliation of ZnS layer from Zn substrate is avoided. The ZnS/Zn has been investigated as the cathode for CO 2 electro-reduction in propylene carbonate/tetrabutylammonium perchlorate (PC/TBAP) in membrane electrolysis cell. The current density of potentiostatic electrolysis remains stable at 6.72 mA/cm2 at voltage −2.4 V and the faradaic efficiency of CO formation reaches to 92%. Comparing with Zn electrode, ZnS/Zn exhibits higher catalytic activity. Highlights • Demonstrating that S-Infiltration is a feasible method for electrode preparation. • Avoiding that the exfoliation of electrode modification layer from the substrate. • ZnS/Zn electrode has large surface roughness that result high current density. • ZnS/Zn electrode shows high CO selectivity and catalytic activity. [ABSTRACT FROM AUTHOR]

An experimental study was carried out using in pilot-scale constructed wetland systems, operated in parallel to treat raw sewage. Each system consisted of a vertical flow (VF) unit that was filled with biochar as the main media, followed by a horizontal flow (HF) unit filled with crushed cement mortar. Hydraulic loading (HL) ranged 340-680 mm/day was applied on the VF wetland units, where high total nitrogen (TN) mass removal rate (20-23 g N/m2 d) was obtained, demonstrating that biochar media had a beneficial effect on the degradation of nitrogenous pollutants. Total phosphorus (TP) removal percentage (concentration based) was ≥ 86% in HF wetlands packed with mortar materials. In one system, the flow direction of the sewage was directed by the deployment of downflow pipes and vertical baffles, aiming to facilitate the formation of aerobic and anaerobic zones in the wetland matrices. The effects of such arrangement were analyzed by comparing pollutant removal efficiencies in the two systems. On average, 99, 96, 93, and 86 percentage removals were obtained for ammonia (NH4-N), TN, biochemical oxygen demand (BOD), and TP, respectively, during the experiments. Biochar and crushed mortar proved to be a highly effective combination as media in subsurface flow constructed wetlands for wastewater treatment. [ABSTRACT FROM AUTHOR]

Developing active immobilized enzymes and characterization of their use conditions is critically important prior to initiating studies of enzyme selectivity and substrate specificity in organic media. To this end, physical immobilization by hydrophobic interactions was performed with three well-characterized cutinases ( Aspergillus oryzae Cutinase (AoC), Humicola insolens Cutinase (HiC), and Thielavia terrestris Cutinase (TtC)) using Lewatit VP OC 1600 as the macroporous support. We found that immobilization yields >98% were achieved for all three cutinases under the following immobilization conditions: 100 mg/g loading ratio, immobilization buffers of 100 mM phosphate pH 8 (AoC and HiC) and 100 mM acetate pH 5 (TtC), mixing at 150 rpm and 30 °C for 24 h. Among the three cutinases, HiC has the highest tolerance towards solvents of increased polarity while TtC has the highest thermal stability (up to 80 °C) in a bulk reaction system that consists of the reactants butanol and lauric acid. In nonane, these cutinases retain >64% of their activity at 90 °C. Furthermore, kinetic stability (residual activity as a function of time) analysis reveals that the cutinases retain >75% residual activity at 70 °C in 3 h. Moreover, at 80 °C, the kinetic stability of TtC is higher than that of HiC and AoC. Collectively, the results herein set the stage for the in-depth evaluation of these catalysts for selective transformations in organic media. [ABSTRACT FROM AUTHOR]

This work was the expansion and in-depth study based on the previously established non-aqueous phase HG system. Aiming at the determination of antimony by the developed non-aqueous phase HG, the effect of different organic media and the sensitization effect of surfactant on the non-aqueous phase HG reaction were investigated. As an important condition, organic media has an important influence on this method. This study found that the surfactant Triton X-114 had very good sensitization effect for non-aqueous HG reaction. The sensitization effect of surfactant in different organic media was different. Among the investigated media, the comprehensive performance of octanol was the best under the sensitization effect of surfactant. Compared with the analytical performance of not adding surfactant, the sensitization factor of the surfactant was 1.55. The sensitization effect of surfactant Triton X-114 on the HG reaction in the octanol media was very significant, which greatly improved the analytical performance of the non-aqueous HG method. Under the optimal conditions, the limit of detection (LOD) was 0.04 μg/L. Compared to conventional HG-AFS, the efficiency of non-aqueous phase HG and the analytical performance of the developed method was considerably improved. [ABSTRACT FROM AUTHOR]

The experimental results of the study of the concentration dependence of the electrical conductivity and diffusion permeability of ion-exchange membranes which are in contact with solutions of weak electrolytes (carboxylic acids) are provided for the first time. An attempt was made to correlate the observed properties of the membrane to their structure, based on the microheterogeneous model. Some features have been revealed that differentiate the behavior of membranes in solutions of strong and weak electrolytes. For example, for anion-exchange membranes, the dependence of the electrical conductivity on the equilibrium solution concentration disappears in the concentration above 0.05 M, and there is an insignificant increase in the electrical conductivity in lower concentrations. An explanation for the observed effects is suggested which takes into account that the electrical conductivity of the gel phase is much higher than the electrical conductivity of an electrically neutral solution. An equation is proposed which connects the electrical conductivity of a membrane with its ion-exchange capacity and mobility of the counterion in the gel phase. Recommendations on the practical aspect of electrodialysis technology for the treatment of weak electrolytes are given. From a fundamental point of view, it is concluded that for a full description of the transport-structural organization of ion-exchange membranes which are in a solution of a weak electrolyte, the knowledge of the concentration dependence of the electrical conductivity and diffusion permeability only is not enough, and other experimental methods are required. [ABSTRACT FROM AUTHOR]

Developing low cost and high efficient electrode for carbon dioxide (CO 2 ) reduction in organic media is essential for practical application. Zn is a cheap metal and has high catalytic effects on CO 2 reduction to carbon monoxide (CO) in aqueous solution. However, little attention has been given to investigate the performance of Zn in organic media for CO 2 reduction. In present work, we have conducted CO 2 reduction in propylene carbonate/tetrabutylammonium perchlorate on Zn due to that propylene carbonate is a widely used industrial absorber, and tetrabutylammonium perchlorate is a commonly used organic supporting electrolyte. In addition, because electrochemical reduction of CO 2 to CO naturally produces H 2 O, we have discussed water effects on CO 2 reduction in propylene carbonate/tetrabutylammonium perchlorate+6.8 wt % H 2 O. Our experiment results reveal that the faradaic efficiency for CO formation reaches to 83%, and the current density remains stable at 6.72 mA/cm 2 at voltage −2.3 V for 4 h. Interestingly, Zn presents higher catalytic activity than Ag, and slightly lower than Au. X-ray photoelectron spectroscopy results confirm that no poisonous species is formed and absorbed on the cathode, which is an important advantage in practical application. [ABSTRACT FROM AUTHOR]