Search

In the conventional leather production process, basic chromium sulphate (BCS) penetrates fully inside the collagen matrix during tanning and forms oligo-nuclear complexes that stabilize the skin structure during basification. Accelerated chromium sulphate complexation by basifying the BCS before full penetration leads to surface tanning and low leather qualities. Therefore, long processing times of 16 h for tanning and basification are common in modern tanneries. We used sodium hydrogen carbonate to basify BCS before penetration. However, instead of conventional tanning we performed CO2 tanning at 30 bar. The influence of accelerated chromium sulphate complexation on the leather quality was investigated. To estimate the structures of the formed chromium complexes, we considered the pH trend of the tanning solution during basification depending on the amount of basifying agent. The distribution of chromium oxide (Cr2O3) and the shrinkage temperature (Ts) in three different layers of the cross section were analysed. The analytics allowed the assessment whether the tanning agent penetrates through the whole cross section or adheres to the surface during CO2 tanning. We show that CO2-intensified tanning allows accelerated chromium sulphate complexation and a reduction in the tanning time from 16 to 4 h. The Cr2O3 is equally distributed, and Ts above 100 °C meets the standards of high-quality wet blue. However, the pH value of the tanning solution must not rise above 4.5 during basification. Otherwise, the Ts decrease dramatically. The feasibility of the process is demonstrated in a 1700-L drum, with a batch size of about 500 kg. The CO2-intensified tanning process has high potential to save time and chemicals and reduce emissions in industrial applications and is commercially competitive. [ABSTRACT FROM AUTHOR]

The leather industry transforms raw hides and skins into high-performance leather products. This transformation requires a high usage of chemicals. About 90% of all leather products are tanned by basic chromium sulphate tanning agents. The use of large quantities of tanning agent causes elevated chromium and sulphate concentrations in the wastewater of conventional tanneries. This article focuses on the reduction of tanning agent consumed by the chromium tanning procedure. Compressed carbon dioxide is used to intensify the process. Carbon dioxide-intensified tanning at 60 bar allows the production of high-quality leather by using about 50 wt% less of tanning agent compared to the conventional tanning process. The chromium and sulphate concentrations in the wastewater generated by the tanning process are highly reduced. Results of full skin tanning (bull skin; up to 10 square metre per skin) in a high-pressure reactor with a volume of 1700-L are presented for the first time. [ABSTRACT FROM AUTHOR]

This research was designed to evaluate the performance of the CuFe12O19/CuS/Xenon system in the degradation of tetracycline in aqueous solutions. In this study, after green synthesis of nanocomposite using the extract of the Artemisia plant, its properties were determined by XRD, FTIR, FESEM, TEM, BET, XPS, DRS, DLS, EDS, VSM, and PL. In addition, parameters affecting the photocatalytic degradation of tetracycline, including time, pH, TC initial concentration, and nanocomposite dose, were assessed. The findings showed that the degradation efficiency increases with increasing pH and catalyst dosage. Under optimum circumstances (pH = 9, nanocomposite dose of 0.5 g/L, and time 200 min), the process efficiency with concentration of 20 mg/L was 100%. The kinetics of the degradation rate of tetracycline obeyed the pseudo-first-order equation. In addition, the results show that after six consecutive cycles, the synthesized catalyst's ability did not significantly reduce. The results of the mineralization tests revealed that the COD and TOC degradation of the synthetic solution of tetracycline with a concentration of 20 mg/L reached 87.25% and 73.06%, respectively, in the optimal reaction conditions. The scavenger experiments confirmed that OH plays the most crucial role in the decomposition process of tetracycline. Generally, the CuFe12O19/CuS/Xenon photocatalytic system can effectively degradation tetracycline from aqueous environments. [ABSTRACT FROM AUTHOR]

Globally, the companies that make commercial use of bamboo culms produce different kinds of solid waste rich in lignocellulosic biomass, which in some cases is not used and is discarded in landfills or incinerated in the open air; losing the possibility of recovering them and using them in other productive sectors. The research objective were to produce a biochar from Guadua agustifolia Kunth sawdust, evaluate its potential environmental and agricultural use, obtain a biochar/TiO2 composite to inactivate Escherichia coli and use the biochar as a soil conditioner in medicinal plants producing phenolic compounds and flavonoids. Biochar composite (produced at 300 °C for 1 h) involved TiO2 at 450 °C for 1 h for inactivation of E. coli (initial concentration: 6.5 ± 0.3 Log10 CFU mL− 1). For agriculture, 2% biochar was used to evaluate B. pilosa L. and G. angustifolia plant growth for 90 days. The biochar/TiO2 composite had a high photocatalytic activity on E. coli, generating a final count of 1.97 ± 0.2 Log10 CFU mL− 1 after 60 min. Biochar (2%) increased the total phenol and flavonoid content in the medicinal plant B. pilosa L. and total phenols in G. angustifolia, tested at the nursery stage. This study provides new information on the conversion and use of G. angustifolia sawdust as an alternative for new bio-based materials with environmental and agricultural applications. In addition, obtaining biochar and composite could positively impact the bamboo production chain in Colombia because of renewable and globally accepted alternatives that help capture gaseous emissions causing the greenhouse effect. [ABSTRACT FROM AUTHOR]

Nitrogen oxides (NOx) have numerous negative effects on both the environment and human health. They are major contributors to photochemical smog and acid rain. As a result, researchers are increasingly focused on developing de-NOx technologies. One effective method for removing NOx from the environment is selective catalytic reduction (SCR), with ammonia serving as the reductant (NH3–SCR). Rare earth-based catalysts have emerged as viable options for low-temperature NH3–SCR. Currently Ce-based NH3–SCR catalysts, such as CeO2–TiO2, CeO2–WO3, CeO2–MoO3, Ce–Mn–TiO2, CeO2–MnO2, Ce0.67Zr0.33O2, and CeO2–Fe2O3 have focused significant attention from researchers. The 4f orbitals of rare earth elements (REEs) are devoid of full electron occupancy. This attribute contributes to their distinct catalytic efficacy when employed as catalyst substrates. The oxygen storage capacity of Ce-based catalysts has further enhanced their popularity. Various methods, including microwave, hydrothermal, precipitation and sol–gel techniques, have been used by researchers to prepare catalysts in order to reduce the NOx emission. The paper has covered the impact of the preparation technique on rare earth catalyst performance and the NH3–SCR reaction mechanism to achieve a wide operating temperature. The global production and reserves of rare earth elements (REEs) worldwide have been thoroughly examined, and catalysts for the reduction of NOx emissions in automobiles by Ce and La have been explored. [ABSTRACT FROM AUTHOR]

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

Development of supercritical carbon dioxide (SC-CO2) dyeing technology for natural fabrics and their blended fabrics is essential for the textile industry due to environmental and economic considerations. Wool (W), polyester (PET) and nylon (N) fabrics and their wool/polyester (W/PET) and wool/nylon (W/N) blended fabrics were dyed in SC-CO2 medium with a synthesized reactive disperse dye containing a vinylsulphone (VS) reactive group, which behaves as a disperse dye for synthetic fibers and a reactive dye for protein fibers. The SC-CO2 dyeing performance of all fabrics was investigated in terms of color strength, fixation, colorimetric and fastness measurements and compared with the conventional aqueous dyeing method. The results obtained indicate that the VS reactive disperse dye structure and non-polar PET component mainly improved colour strength (K/S) values of the dyed PET fabric and W/PET blended fabrics in SC-CO2 compared with those in the aqueous medium. Also, SC-CO2 dyeing has a notable influence on a*, b* and C* values of the dyed PET, N and W/PET fabrics and showed that the uptake of the VS reactive disperse dye and their appearance colors are higher and more saturated than the aqueous dyed samples. The levelling and fastness properties of all dyed fabrics in SC-CO2 medium are similar to those obtained in the aqueous medium. It was observed that VS reactive disperse dye penetrates well into the PET fabric and is chemically bound with the W fabric using both SC-CO2 and aqueous media and did not display significant color difference (∆E) values of W, PET and W/PET fabrics even after 20 washing cycles. The study claims that the VS reactive disperse dye structure and dyed PET-based wool blended fabric are good candidates for industrially SC-CO2 dyeing technology. [ABSTRACT FROM AUTHOR]

In this study, experimental carry out of liquid–vapor and solid–liquid phase transitions were conducted for the ternary system {CO2 (1) + ethanol (2) + acetaminophen (3)} at different concentrations of paracetamol in ethanol for temperatures from 313 to 333 K and pressures up to 12 MPa. Experimental high pressure phase transition data were obtained using the static method in a variable volume view cell. Experimental data were compared with the literature for systems containing acetaminophen in a saturated solution. The presence of paracetamol in the binary system {CO2 (1) + ethanol (2)} significantly alters the behavior of the phase under the conditions of temperature and concentration studied. It was observed that in the ternary system {CO2 (1) + ethanol (2) + acetaminophen (3)} with a saturated solution at the lowest temperature, 313 K, CO2 acts as a cosolvent for mole fractions lower than 0.6. Thermodynamic simulations employing the Perturbed Chain Statistical Associating Fluid Theory (PC-SAFT) Equations of State (EoS) aligned the experimental results adequately. The observed minimal deviations in pressure and temperature validate the efficacy of the thermodynamic models applied in this study. [ABSTRACT FROM AUTHOR]

Current study focuses on the development of a promising technique to prepare D-mannitol xanthate-based hydrogel (DMXAGAHs hydrogel) using a free radical co-polymerization technique for eliminating Cu2+ and Ni2+ ions from aqueous solutions. The UV, FTIR, TGA, ΔpHPZC and SEM analysis have been used for the characterization of the synthesized hydrogel. The percent swelling (%SR) of the prepared DMXAGAHs-3 hydrogel has been found to be 28,123, 13,433 and 11,177% and water retention ratio (%WRR) was 78.02, 78.84 and 79.22% for distilled water, tap water and gray wastewater. Additionally, the maximum metal ion removal was obtained as 96.9 for Cu2+ ions and 94.1% for Ni2+ ions by DMXAGAHs-3 hydrogel at optimum adsorbent dosage of 3.125 g/L, pH of 7, temperature 45 °C, initial concentration 1000 mg/L and contact time 60 min, respectively. The experimental data were found to be well-fitted with the Langmuir isotherm model. The optimal adsorption capacities of DMXAGAHs-3 hydrogel, as per the Langmuir model, were determined to be 371.74 mg/g for Cu2+ ions and 296.73 mg/g for Ni2+ ions, respectively. The pseudo-second-order kinetic model has been found to be the most suitable model for describing the kinetic behavior of the adsorption process. The rate constant according to this model has been found to be 3.0 × 10−4 g/(mg.min) for Cu2+ and 3.2 × 10−4 g/(mg.min) for Ni2+ ions, respectively. The negative ΔG values (− 5.567 kJ/mol for Cu2+ and − 4.647 kJ/mol for Ni2+ ion) at optimum temperature of 45 °C indicates that the adsorption process is spontaneous in nature along with positive ΔH values (79.80 and 25.38 kJ/mol for Cu2+ and Ni2+ ion) and ΔS values (267.81 and 100.51 J/Kmol for Cu2+ and Ni2+ ion) also suggests adsorption process is endothermic in nature and results in the increase in the degree of randomness of metal ions on the DMXAGAHs-3 hydrogel during the adsorption process. In addition, the DMXAGAHs-3 hydrogel has shown a remarkable desorption efficiency with 82.36 and 80.21% desorption for Cu2+ and Ni2+ ions even on 5th cycle and the hydrogel can be utilized many times for the adsorption of heavy metal ions. [ABSTRACT FROM AUTHOR]

Electrocatalytic CO2 reduction technology offers an effective way to convert CO2 into valuable chemicals and fuels, presenting a sustainable solution for carbon emissions. Current electrocatalytic CO2 reduction technologies encounter significant issues such as salt precipitation and hydrogen evolution, which prevent energy conversion efficiency, selectivity, current density, and stability from simultaneously meeting industrial standards. In recent years, researchers have discovered that increasing the CO2 pressure on the gas supply could enhance the coverage of the catalyst and activate more CO2 reduction reaction sites on the catalyst surface, which provides a practical and effective approach for optimizing the energy conversion and mass transfer. In this review, we provide a comprehensive review of the development history and current status of high-pressure CO2 electrocatalytic reduction technology, focusing on its reaction devices, catalytic performance, and reaction mechanisms. Furthermore, we summarize and offer insights into the most promising research avenues to propel the field forward. Highlights: 1. A briefly discussion on the challenges faced by CO2 electrochemical reduction. 2. The state-of-the-art progress of the high-pressure CO2 electrochemical reduction for chemical synthesis is summarized. 3. The bottlenecks of current high-pressure CO2 electrochemical reduction technology are highlighted and potential optimization strategies are proposed. [ABSTRACT FROM AUTHOR]

Purpose: Most eukaryotic cells have a plasma membrane with glycoproteins on the outer leaflet and cytoplasmic proteins on the inner leaflet. However, the microsporidians examined have a peculiar outer membrane with cytoplasmic proteins on the surface. His study was to determine if this is true and identify the presence of key cytoplasmic proteins on the exterior of the sporoplasm and spore stages. Methods: Specific probes including GFP-labeled genes, antibodies, and electron microscopy were applied to studies on the sporoplasm and spore stages of different microsporidian species. Results: Cytoplasmic membrane proteins cadherin, intermediate filaments, dynactin p150Glued and tubulin were identified on the outer leaflet of the exterior membrane of the sporoplasm or spore stages of Spraguea americanus, Anncaliia algerae, Ameson michaelis and Thelohania sp. Conclusion: The invasive sporoplasm stage of microsporidians acquires an outer membrane from a cytoplasmic organelle and it has been shown that the outside surface of this membrane bears cytoplasmic proteins. This membrane retains these cytoplasmic proteins even on the spore stage. For an intracellular parasite that locates directly within the cytoplasm of a host cell, the presence of these cytoplasmic proteins on the surface of the parasite appears to have a significant effect on the host's response. [ABSTRACT FROM AUTHOR]

Arsenic contamination in aqueous media is a serious environmental problem, especially in developing countries. In this research, the Box-Behnken response surface methodology was used to optimize the most relevant variables affecting arsenic adsorption on the ZnO-halloysite surface, including temperature, adsorbent dosage, pH, contact time, and As (III) initial concentration. The regression analysis indicated that the experimental data were appropriately fitted to a quadratic model with the adjusted R-squared value (R2) of 0.982 for As(III) adsorption capacity and a linear model with R2 of 0.931 for As(III) removal. The p-values for both adsorption capacity and removal efficiency were below 0.05, with F-values of 116.91 and 115.58, respectively, supporting the model's validity. The optimum conditions for maximum removal of As(III) were determined through numerical and graphical optimization using the desirability function. It was found that the optimum conditions for adsorption were pH = 7.99, contact time of 3.99 h, As(III) initial concentration of 49.96 mg/L, and adsorbent dosage of 0.135 g/40 ml. The accuracy of the optimization procedure was confirmed by a confirmatory experiment, which showed a maximum arsenic removal of 91.31% and an adsorption capacity of 12.63 mg/g under optimized conditions. Moreover, XPS analysis was performed at different pH levels to investigate the As (III) adsorption mechanism. The results demonstrated that As(III) adsorption occurs at acidic and neutral pH levels. On the other hand, when pH is increased to 8, As (III) oxidizes to As (V), and then adsorption occurs. [ABSTRACT FROM AUTHOR]

Recently, phytochemicals play an important role in cancer management. Curcumin (CUR), a natural phytochemical, has been co-administered with widespread chemotherapeutic agents such as doxorubicin (DOX) due to its excellent antitumor activity and the ability to lower the adverse reactions and drug resistance cells associated with DOX use. The present study aims to determine DOX and CUR utilizing a label-free, selective, sensitive, and precise synchronous spectrofluorimetric method. The obvious overlap between the emission spectra of DOX and CUR prevents simultaneous estimation of both analytes by conventional spectrofluorimetry. To solve such a problem, synchronous spectrofluorimetric measurements were recorded at Δλ = 20 nm, utilizing ethanol as a diluting solvent. Curcumin was recorded at 442.5 nm, whereas DOX was estimated at 571.5 nm, each at the zero-crossing point of the other one. The developed method exhibited linearity over a concentration range of 0.04–0.40 μg/mL for CUR and 0.05–0.50 μg/mL for DOX, respectively. The values of limit of detection (LOD) were 0.009 and 0.012 µg/mL, while the values of limit of quantitation (LOQ) were 0.028 and 0.037 µg/mL for CUR and DOX, respectively. The adopted approach was carefully validated according to the guidelines of ICH Q2R1. The method was utilized to estimate CUR and DOX in laboratory-prepared mixtures and human biological matrices. It showed a high percentage of recoveries with minimal RSD values. Additionally, three different tools were utilized to evaluate the greenness of the proposed approach. [ABSTRACT FROM AUTHOR]

Turbulent plumes are fascinating to study in large part due to the ability to see the eddies and structures that comprise the exterior structure as they develop in space and time. We perform a laboratory study in which positively buoyant turbulent plumes are generated in a quiescent water tank. Buoyancy is varied by modifying the relative percentages of isopropyl alcohol to water in a mixture placed in a head tank. Photographs captured at steady frame rates record the evolution of the plume as it develops in time and space. A custom algorithm tracks the visible exterior outline of the plume, from which eddies and structures can be identified along the interface between the plume fluid and ambient fluid. Statistical analyses are performed to characterize differences in the distributions of external structures to study their dependence on relative buoyancy between the fluids. Spectral analysis of the edge signal of the plume reveals a - 2.2 slope, indicative of the range of eddy lengths that comprise turbulent plumes. We explore the relationship between buoyancy with both the plume front velocity and plume spread angle. We find the front velocities to be functions of both the buoyancy and source Reynolds number. However, the spread angles were found to vary only with buoyancy of the plumes, thus proportional to their Richardson numbers. [ABSTRACT FROM AUTHOR]

Pretreatment is an important step in lignocellulosic bioethanol production which aims to reduce lignin content and break down lignocellulosic structure thereby increasing the accessibility of enzymes in hydrolysis. Therefore, this research explored the pretreatment process on oil palm empty fruit bunch (EFB) with CO2 impregnation followed by alkali explosion. EFB was impregnated with CO2 at 5 °C for 12 h. After impregnation, EFB was mixed with 2.5 M of NaOH solution (1:5 of S/L ratio) in an alkali explosion reactor. Alkali explosion was conducted at 150 °C, 4 kg/cm2 of pressure with the variation of reaction time for 15, 30, and 45 min. The parameters analyzed in this study include EFB recovery, EFB composition and characteristics, glucose yields, and ethanol yields. EFB composition was analyzed as cellulose, hemicellulose, and lignin while the characteristics of the EFB were examined in functional groups. The results indicated that combined pretreatment using CO2 impregnation followed by 15 min of alkali explosion obtained higher delignification of EFB, glucose, and ethanol yield than only alkali explosion for 30 min. The highest glucose and ethanol yields were 99.33 and 83.80 w/w% of glucose mass in EFB, respectively. These results prove that CO2 can be used as an impregnation agent in lignocellulosic pretreatment and could be combined with alkali explosion. [ABSTRACT FROM AUTHOR]

Microsporidians are obligate parasites of many animals, including mosquitoes. Some microsporidians have been proposed as potential agents for the biological control of mosquitoes and the diseases they transmit due to their detrimental impact on larval survival and adult lifespan. To get a more complete picture of their potential use as agents of biological control, we measured the impact of Vavraia culicis on several life-history traits of Aedes aegypti and Anopheles gambiae. We measured the infection dynamics and clearance rate for the two species, and we assessed sexual dimorphism in infection dynamics within each species. Our results show differences in infection dynamics, with Ae. aegypti life-history traits being more affected during its aquatic stage and exhibiting higher clearance of the infection as adults. In contrast, An. gambiae was unable to clear the infection. Additionally, we found evidence of sexual dimorphism in parasite infection in An. gambiae, with males having a higher average parasite load. These findings shed light and improve our knowledge of the infection dynamics of V. culicis, a microsporidian parasite previously recognized as a potential control agent of malaria. [ABSTRACT FROM AUTHOR]

White feces syndrome (WFS) in Penaeus vannamei has a dynamic etiology in shrimp culture. The etiological factors associated with WFS, namely Enterocytozoon hepatopenaei (EHP), aggregated transformed microvilli (ATM), midgut parasites, and environmental factors (temperature, pH, salinity, ammonia, nitrate, and nitrite) were investigated within shrimp farms in the coastal districts of Tamil Nadu. The investigation encompassed 62 WFS-affected shrimp farms, along with a subset of three WFS-negative farms to ensure a comprehensive analysis. Severity scores (0, 1, and 2) were assigned for each factor and their interrelationship was investigated using principal component analysis (PCA). The PCA analysis highlights the endemic presence of EHP (52 farms), along with elevated nitrate, ammonia, and water salinity, as key driving factors of WFS in shrimp farms among the coastal districts of Tamil Nadu. Histological evidence unveils the high prevalence of ATM structures (54 farms) in the hepatopancreas of WFS-affected shrimps. Micro eukaryotes, including gregarines, cestodes, and digeneans, were commonly observed parasites in the white midgut of WFS-affected shrimps. The occurrence of WFS appears to be more frequent during rainy days and is particularly prevalent between 40 and 50 days of culture (DOC). The insights on the interrelationship between the etiological factors associated with WFS can contribute to a better understanding of management strategies and aid in the development of preventive measures to mitigate the occurrence of WFS in shrimp farms across Tamil Nadu, India. [ABSTRACT FROM AUTHOR]

The mutual effects and the structure of interface in blends of low-density polyethylene (PE) and polycaprolactone (PCL) with different ratios of components (differing by 10 wt %) were studied. The creation of blended composites of this kind based on one polymer capable of photodegradation under the action of ultraviolet radiation and another polymer prone to hydrolytic degradation under the action of microbiota makes it possible to obtain materials with an enhanced ability to undergo fast abiotic and biotic degradation after use. Blended films with high PCL contents (over 80 wt %) showed mutual compatibility of polymers, forming a developed interfacial layer, which imparts increased tensile strength and hardness to the film. The phase inversion ranges were determined to be 10–30 wt % PCL (continuous PE phase with a discontinuous PCL phase), 40–60 wt % PCL (net-in-net structure) and 70–90 wt % (continuous PCL phase with a discontinuous PE phase). The composite containing 70 wt % PCL was characterized by the greatest defectiveness of internal structure, and the composite with 90 wt % PCL had the most optimum set of both mechanical and technological properties. [ABSTRACT FROM AUTHOR]

Water pollution caused by highly toxic arsenic (As) and lead (Pb) poses a serious threat to water quality. Hence, the development of materials for their effective removal from water continues to attract research attention. The present study reports functionalized graphitic carbon nitride nanosheets (GCN) as a green and low-cost adsorbent for the removal of As and Pb from polluted water. The adsorbent was prepared through the protonation and hydroxyl and cyano functionalized graphitic carbon nitride to form H/GCN and OH/CN-GCN respectively. Characterization techniques including Fourier transform infrared (FTIR), X-ray diffraction, and scanning electron microscopy were respectively used to study functional groups, structure, and morphology of the adsorbents. The adsorption study showed that modification of GCN with −OH and CN− ions in OH/CN-GCN, increased the density of negative charges on the functionalized surface, which also enhances the attraction of the positively charged ions. This may be responsible for the improved removal of As and Pb from wastewater compared to H/GCN. Isotherm studies on the adsorption behavior of OH/CN-GCN suggest that Langmuir isotherm model corroborates with the As adsorption. Therefore, indicating that the removal of As via its adsorption onto OH/CN-GCN is a surface phenomenon. However, the adsorption of Pb could be described as mainly a multilayer adsorption process, based on its R2 value. It is proposed that the −OH and CN− groups on the tri-s-triazine units of GCN nanosheets may be responsible for the adsorption process. The prepared materials are promising adsorbents that nay find useful applications in wastewater treatment plants involving advanced oxidation processes. [ABSTRACT FROM AUTHOR]

Stratified water columns are often found in lakes and oceans. Stratifications result from differences in density due to salt concentration, temperature, solid content and oxygenation. The stability of stratifications affects bioactivity, sedimentation, contaminant transport and environmental remediation. This study investigates the evolution of 6 stratified water columns created by differences in salinity, suspended minerals and the presence of a bottom heat source. We use acoustic wave reflection, photography, and both electrical conductivity and temperature profiles to track changes in stratification. Results show that multiple concurrent processes emerge across layers in otherwise quiescent water bodies. Dissimilar chemo-thermo conditions give rise to chemical and thermal diffusion, convection, and double-diffusion convection. When stratification involves suspended particles, interlayer processes include diffusiophoresis, flocculation/aggregation, sedimentation, osmosis, and chemo-consolidation; in this case, the specific surface and surface charge of suspended particles, and the salt concentration in contiguous layers determine aggregation-sedimentation-consolidation patterns. The interlayer transition zone acts as a high-pass filter that preferentially reflects low-frequency long-wavelength P-waves; invasive thermal and electrical conductivity probes provide complementary information and may identify stratification even when it is undetected by acoustic signals. [ABSTRACT FROM AUTHOR]

Herein, antimony-doped cerium vanadate (Sb-CeVO4) has been reported as photocatalyst and active solid-phase adsorbent for the removal of crystal violet (CV) dye from aqueous medium. The synthesized materials were characterized by UV–Vis, Fourier transform infrared (FTIR), X-ray diffraction (XRD), and scanning electron microscopy-energy-dispersive X-ray (SEM–EDX) techniques. X-ray diffraction (XRD) depicted the formation of crystalline CeVO4 and Sb-CeVO4 having tetragonal phase. The SEM analysis showed the particle sizes of materials in a range 25–45 nm. The computed band gap energy for 10%-Sb-CeVO4 (3.68 eV) was the lowest among all, indicating its more appropriateness for photocatalytic removal of crystal violet dye (82.6%) in 35 min only. In order to determine the adsorption of dye, various parameters such as contact time, dose of adsorbent, temperature, dye concentration, shaking speed/ RPM, and pH were optimized. The adsorption values were 50, 54.6, 114.9, 123.5, 153.8, and 285.7 mg/g by using undoped-CeVO4, 1%-Sb-CeVO4, 3%-Sb-CeVO4, 5%-Sb-CeVO4, 7%-Sb-CeVO4, and 10%-Sb-CeVO4, respectively, at optimal conditions (temperature = 30 °C, shaker speed = 100 RPM, time = 35 min, dye concentration = 45 ppm, pH = 6–7, adsorbent dose = 0.01 g). Langmuir model showed adsorption capacity (285.7 mg/g) at optimal conditions for 10%-Sb-CeVO4, whereas kinetic modeling supported the pseudo-second-order model for dye sorption. The thermodynamic parameters, i.e., Δ G°, Δ H°, and Δ S°, demonstrated that sorption was favorable, spontaneous, and exothermic. Hence, it can be safely concluded that Sb-doped CeVO4 could be highly effective for the photocatalytic and sorptive removal of dyes from wastewater. [ABSTRACT FROM AUTHOR]

The synthesis of a number of bimetallic nanoparticles has been carried out in the past few years for commercial scale applications to promote environmental sustainability. This has been possible as the bimetallic nanoparticles possess harmonized physical and chemical properties. As compared to monometallic catalysts, these bimetallic nanoparticles displayed improved catalytic activity which may be due to the synergistic bonding among constituents and additional degrees of freedom. Furthermore, the manifestation of two different metals in bimetallic catalysts acts as a dynamic center and provides a favorable environment for the reactants to accelerate the reaction. The present review outlines a variety of procedures for the synthesis of bimetallic nanoparticles. A comparison has also been made between biosynthesis and other conventional methods of preparation. In addition, application of these bimetallic nanoparticles for removal of hazardous organic pollutant, viz. 4-nitrophenol, has also been explored. This review aims at providing the researchers, a comprehensive outline of recent developments in this discipline. [ABSTRACT FROM AUTHOR]

This research aimed to microencapsulate porcine liver hydrolysate using different coat materials (arabic gum, maltodextrin, whey protein, a combination of whey protein with maltodextrin, xanthan gum, and soy protein isolate) by two different encapsulating methods (spray drying and freeze-drying) to obtain capsules with controlled release and resistant to the passage through the gastrointestinal tract. The thermogravimetric analysis of the microcapsules evidenced good thermal stability. All microparticles presented low water activity, being considered biologically and biochemically stable. In the gastrointestinal simulation, the antioxidant activity was evaluated, and all the coat materials were adequate to protect the biopeptides against gastrointestinal conditions, except for xanthan gum, which presented low efficiency. The antimicrobial activity was also evaluated in the in vitro digestion for 4 h, the microcapsules produced with Gum Arabic, Soy Protein Isolate and Whey+Malto (only those produced in a lyophilizer) showed an inhibitory action against Candida albicans and the microcapsules produced with Whey Protein, Whey+Malto and Soy Protein Isolate (only those produced in spray drying) showed inhibition for Staphylococcus aureus. The results obtained for gastrointestinal simulation demonstrated that microencapsulation preserved the antioxidant and antimicrobial activity of the pork liver hydrolyzate, confirming its importance for the maintenance of biopeptides. [ABSTRACT FROM AUTHOR]

Oxygenates production from the partial oxidation of liquid fuel is required for a cleaner combustion. The effect of Mn/Fe ratio was investigated to improve the oxygenates formation via plasma catalytic n-C5H12 partial oxidation over FeMn/Al2O3 catalyst. The oxygenates selectivities exhibited a volcano shape with the Mn/Fe ratio and the highest value of 69% was obtained at Mn/Fe ratio of 7/3. The oxygenates selectivities were dominated by both the acidity and active oxygen species of catalyst, which could be tuned by Mn/Fe ratio. A close relationship between oxygenates selectivities, acidity, and active oxygen species of catalyst was established. The higher the active oxygen species content and the lower the acidity, the higher the oxygenates selectivities. [ABSTRACT FROM AUTHOR]

On behalf of the European Commission, the European Chemicals Agency (ECHA) published a restriction proposal in early 2019 to minimize the EU-wide placement of intentionally added microplastics in products (ECHA, 2019). Soccer fields in the sense of artificial turf systems (ATS) and their infill are included in this definition and are suspected to be the fourth largest source of microplastic emissions. In the present study, we queried a sample of 191 soccer players regarding their awareness of the problem of synthetic infill discharge from ATS into the environment and whether they are aware of its environmental consequences. In addition, we investigated whether the soccer players expressed a willingness to implement interventions against the discharge of microplastic granules. Results suggest a moderate (rather than high or low) level of problem awareness among soccer players. In particular, issue-specific problem awareness was significantly related to the willingness to implement an intervention measure, being its strongest predictor. Our results further suggest that in order to optimize the awareness and legitimation of intervention measures among club members, more information (i.e., environmental knowledge) should be provided. The present work makes a first important research contribution to the awareness analysis regarding microplastic granulate from ATS. [ABSTRACT FROM AUTHOR]

A new era of lunar exploration has begun bringing immense opportunities for science as well. It has been proposed to deploy a new generation of observatories on the lunar surface for deep studies of our Universe. This includes radio antennas, which would be protected on the far side of the Moon from terrestrial radio interference, and gravitational-wave (GW) detectors, which would profit from the extremely low level of seismic disturbances on the Moon. In recent years, novel concepts have been proposed for lunar GW detectors based on long-baseline laser interferometry or on compact sensors measuring the lunar surface vibrations caused by GWs. In this article, we review the concepts and science opportunities for such instruments on the Moon. In addition to promising breakthrough discoveries in astrophysics and cosmology, lunar GW detectors would also be formidable probes of the lunar internal structure and improve our understanding of the lunar geophysical environment. [ABSTRACT FROM AUTHOR]

The increasing severity of global climate and energy problems has made renewable energy an inevitable choice for achieving a low-carbon society. Hydrogen is regarded as one of the most promising renewable energy due to its excellent characteristics, such as abundant and extensive resources, high calorific value, and non-pollution. How to achieve efficient hydrogen storage is one of the main hot spots of hydrogen energy research. For on-board hydrogen storage systems, which could be used for portable power sources and fuel cell vehicles, how to store hydrogen safely and effectively is one of the most urgent technological bottlenecks to overcome. The solid-state storage based on hydrogen storage materials has the advantages of low hydrogen storage pressure, high energy efficiency, safety and reliability, compared to conventional compressed hydrogen and cryogenic liquid hydrogen storage methods. It may be one of the most promising solutions to solve the above problems. Among the hydrogen storage materials, the lightweight composite hydrides Li–Mg–N–H system holds great promise for vehicular hydrogen storage applications owing to its moderate thermodynamic properties (∆Hdes ~ 44 kJ mol−1 H2 and ∆Sdes ~ 112 J mol−1 H2·K) and relatively high hydrogen capacity (~ 5.6 wt%). However, the Li–Mg–N–H material itself has poor cycling performance and a high energy barrier, resulting in a low dehydrogenation rate and high operating temperature. Apart from this, the multi-field coupling of mass and energy transfer also poses a challenge, hindering its on-board applications. In this paper, we present the modification methods and research status of the Li–Mg–N–H system's hydrogen storage materials. The effects of composition modification, nanocrystallization and catalyst addition on the thermal/kinetic properties of hydrogen storage materials in the Li–Mg–N–H system are expounded. The difficulties and directions for enhancing the hydrogen storage performance of Li–Mg–N–H system are discussed. [ABSTRACT FROM AUTHOR]

Microsporidia are an early-diverging group of fungal pathogens with a wide host range. Several microsporidian species cause opportunistic infections in humans that can be fatal. As obligate intracellular parasites with highly reduced genomes, microsporidia are dependent on host metabolites for successful replication and development. Our knowledge of microsporidian intracellular development remains rudimentary, and our understanding of the intracellular niche occupied by microsporidia has relied on 2D TEM images and light microscopy. Here, we use serial block-face scanning electron microscopy (SBF-SEM) to capture 3D snapshots of the human-infecting species, Encephalitozoon intestinalis, within host cells. We track E. intestinalis development through its life cycle, which allows us to propose a model for how its infection organelle, the polar tube, is assembled de novo in developing spores. 3D reconstructions of parasite-infected cells provide insights into the physical interactions between host cell organelles and parasitophorous vacuoles, which contain the developing parasites. The host cell mitochondrial network is substantially remodeled during E. intestinalis infection, leading to mitochondrial fragmentation. SBF-SEM analysis shows changes in mitochondrial morphology in infected cells, and live-cell imaging provides insights into mitochondrial dynamics during infection. Our data provide insights into parasite development, polar tube assembly, and microsporidia-induced host mitochondria remodeling. Microsporidia are obligate intracellular parasitic fungi that can cause opportunistic infections in humans. Here, Antao et al. investigate the intracellular life cycle of human-infecting Encephalitozoon intestinalis using serial block-face scanning electron microscopy to characterize parasite organelle development and host-cell mitochondrial remodeling. [ABSTRACT FROM AUTHOR]

Pyrolysis in an inert atmosphere is a widely applied route to convert tannery wastes into reusable materials. In the present study, the Cr(III) conversion into the toxic hexavalent form in the pyrolyzed tannery waste referred to as KEU was investigated. Ageing experiments and leaching tests demonstrated that the Cr(III)–Cr(VI) inter-conversion occurs in the presence of air at ambient temperature, enhanced by wet environmental conditions. Microstructural analysis revealed that the Cr-primary mineral assemblage formed during pyrolysis (Cr-bearing srebrodolskite and Cr-magnetite spinel) destabilized upon spray water cooling in the last stage of the process. In the evolution from the higher to the lower temperature mineralogy, Cr is incorporated into newly formed CrOOH flakes which likely react in air forming extractable Cr(VI) species. This property transforms KEU from an inert waste to a hazardous material when exposed to ordinary ambient conditions. [ABSTRACT FROM AUTHOR]

The molybdate-PCeCl nanocomposite was prepared utilizing several factors such as pH contact time and initial concentration, and it was then described using FTIR, XRD, SEM, and EDX mapping. Column dimensions, Mo(VI) feed solution concentration, and other variables influencing 99mTc(VII) elution, such as column dimensions, PCeCl nanocomposite quantity, and eluate flow rate, were explored to prepare the 99Mo/99mTc generator. The radiochemical, radionuclidic, and chemical purity of eluted 99mTc was studied, and its suitability for medical use was determined. The chemisorption process occurs between Mo(VI) ions and the PCeCl nanocomposite, and the adsorption results are consistent with the Langmuir isotherm, with a monolayer adsorption capacity of 93.55 mg g−1. [ABSTRACT FROM AUTHOR]

In recent years, water pollution has become one of the most dangerous problems facing the world. Pollution of water with heavy metals and different dyes has caused many harmful effects on human health, living organisms and our environment. In this study, iron oxide nanomagnetic composite from Pterocladia Capillacea red algae-derived activated carbon (PCAC-IO) was synthesized by co-precipitation method using different iron salts and different base solutions. The synthesized nanocomposite was investigated with various characterization techniques such as FTIR, BET, SEM-EDX, TEM, XRD, and VSM. The obtained PCAC-IO adsorbent was used for Cr6+ ions and Mordant Violet 40 (MV40) dye removal. The adsorption mechanism of Cr6+ ions and MV40 dye on PCAC-IO was examined using several adsorption and kinetic isotherm models. Langmuir and Freundlich models were investigated using experimental data. Pseudo-first-order (PFO), Pseudo-second-order (PSO) and intraparticle diffusion models (IPDM) were applied to identify the adsorption mechanism. It has shown that the PSO kinetic model fits better with the experimental data obtained from PCAC-IO. This result can be interpreted as the adsorption of the adsorbate on the nanocomposite as chemical adsorption. The optimum conditions for maximum Cr6+ ions removal (96.88%) with PCAC-IO adsorbent occur at room temperature, 5 g L−1 adsorbent concentration, 100 mg L−1 initial pollutant concentration, pH 1 and at the end of 180 min, while maximum MV40 dye removal (99.76%), other conditions being the same, unlikely it occurred at pH 2.06 and after 45 min. The most suitable model for Cr6+ ions removal under the conditions of 1 L−1 g adsorbent concentration and 400 mg L−1 adsorbate concentration was Langmuir (Qmax = 151.52 mg g−1), while for MV40 removal it was Freundlich (Qmax = 303.03 mg g−1). We propose the use of activated carbon-supported iron oxide prepared from bio-waste material, especially from Pterocladia Capillacea red algae, as a promising adsorbent with high efficiency in the removal of Cr6+ ions and MV40 dye from aqueous media. [ABSTRACT FROM AUTHOR]

Urban energy system planning is vital for cities shifting towards a more sustainable and integrated energy system. Hydrogen is considered one of the most promising solutions in future energy systems. Previous work on hydrogen energy systems predominantly analysed hydrogen models on a national level or only parts of the mobility sector. This indicates a research gap for geospatial models that include multiple sectors in which hydrogen can be used. These models can be used to support decision-making processes around the hydrogen economy in cities. This study presents a holistic model addressing the geospatial modelling of hydrogen demand in urban areas. It proposes a method that integrates a variety of open source data, including geodata, earth observation data and energy data to estimate hydrogen demand top down for the industrial feedstock (steel, ammonia, organic chemistry), process heating, and mobility (buses, trucks, trains, airplanes, ships) sectors. The proposed method can also be extended to different sectors. The method is validated by modelling the hydrogen demand in all German cities and benchmarking it with national studies. This study's results are within the same range as the results of national studies. For this paper, the method is applied for two case studies in Freiburg im Breisgau and Frankfurt am Main. Applying this method in urban areas shows potential hydrogen demand hotspots in these areas. The model's results help policymakers and industry stakeholders make informed decisions about the development of hydrogen infrastructure and facilitate the adoption of hydrogen as a low-carbon energy carrier. Future research could explore the temporal aspects of hydrogen demand and the spatial influence of hydrogen demand on future hydrogen production facilities such as electrolysers. [ABSTRACT FROM AUTHOR]

Metronidazole is a type of antibiotic that is commonly used to treat bacterial infections in both humans and animals. The objective of this study was to eliminate MDZ from aqueous solutions using MRM. To gain a better understanding of the adsorption mechanism, we utilized kinetic and isotherm models to investigate the factors that affect the removal of MDZ. The Box–Behnken model was utilized to design experimental factors, which included the initial concentration of MDZ (ranging from 5 to 80 mg/L), MRM dose (ranging from 0.1 to 0.7 g/L), reaction time (ranging from 10 to 60 min), and pH (ranging from 4 to 10). Analysis of the adsorbent using FESEM, FTIR, EDX, DLS, and zeta potential provided valuable insights into its morphology, surface properties, functional groups, size, and electrical charge. Acid modification of red mud increased the porosity and number of pores on the adsorbent surface, thereby enhancing its ability to adsorb the MDZ antibiotic. The FTIR spectrum displays various bands corresponding to different functional groups, such as O–H, Si(Al)–O, Fe–O, and carbonate groups. EDX analysis revealed that the composition of MRM includes carbon, oxygen, and nitrogen elements. The DLS and zeta potential data demonstrate the impact of particle size and electric charge of the adsorbent on the removal of MDZ. The maximum removal of MDZ, which was 69.87%, was achieved at an MDZ concentration of 42.5 mg/L, a pH of 7, a contact time of 35 min, and an adsorbent dose of 0.4 g/L. The removal of MDZ follows both the pseudo-second-order model and the Langmuir model. The maximum adsorption capacity was found to be 6.04 mg/g. The findings of this study indicate that MRM successfully removes MDZ from aqueous solutions. [ABSTRACT FROM AUTHOR]

For many high-pressure processes employing pressurized fluids, such as supercritical fluid extraction (SFE) of natural matrices with supercritical carbon dioxide (scCO2), CO2 plays a central role as a solvent, solubilizing agent, or medium for extracting and processing diverse food-type substances, in which the knowledge on the solubility behavior of multiple compounds at the varying process conditions is essential in the process design, but not completely understood. High-pressure solubility data in pure scCO2 or cosolvent-modified CO2 of distinct types of organic compounds found in or related to food (mainly vegetable oils, essential oils, carotenoids, phenolics, and vitamins) published in the last decade were reviewed, encompassing temperatures of 298–373 K and pressures up to 95 MPa. Crossover phenomena, solubility enhancements in cosolvent systems or those containing a co-solute, and the antisolvent feature of CO2 are also discussed. Current models for the correlation of solubility data by semi-empirical and thermodynamic models are compared, and the limitations of each class of models are highlighted. Lipid-soluble substances (fatty acid esters, fatty acids, and essential oils) are the most CO2-soluble food-type substances in contrast to polar and complex polyphenols and carotenoids. The investigated solutes can be obtained by SFE, separated by fractionation using scCO2, or applied to enzymatic reactions and particle formation processes. It was concluded based on recent applications that improved SFE, effective separation factors for supercritical fractionation, better solubilization of reactive systems, and supersaturation conditions to obtain micronized particles could be established based on the solubility behavior of dissolved solutes in the supercritical media at high pressures. [ABSTRACT FROM AUTHOR]

In this work, the optimum condition for hydrocracking waste palm oil (WPO) over Mo/SiO2 catalyst was studied in order to obtain biofuel with high level hydrocarbon. Natural source Parangtritis beach sand was utilized to provide amorphous silica support for preparing Mo/SiO2 hydrocracking catalyst via wet impregnation in five different Mo concentrations: 1.22 wt%, 4.50 wt%, 4.66 wt%, 5.74 wt%, 7.63 wt%, and each is labelled as Mo(A)/SiO2, Mo(B)/SiO2, Mo(C)/SiO2, Mo(D)/SiO2, and Mo(E)/SiO2, respectively. With the use of amorphous SiO2, two MoO3 structures, α-MoO3 and h-MoO3, were found in catalysts comprising Mo ≥ 4 wt% in XRD analysis. This study shows that at 550 °C with 1:300 catalyst:feed ratio, Mo(C)/SiO2, which possesses the highest total acidity among the others (1.71 mmol/g), exhibits an excellent hydrocracking performance by producing over 87 wt% liquid conversion containing 94 wt% hydrocarbon compounds. Moreover, the reusability of Mo(C)/SiO2 was found to be effective for 5 hydrocracking runs before it started to show a declining conversion level. Regeneration of Mo(C)/SiO2 was surprisingly able to recover its initial performance by producing 75.78 wt% liquid product containing 90.03 wt% hydrocarbon in the hydrocracking of WPO. [ABSTRACT FROM AUTHOR]

The Baltic Sea is among the fastest-warming seas globally in recent decades affecting biogeochemical conditions such as euxinic areas but also pelagic and benthic marine ecosystems. It is therefore crucial to understand how this heat gain is distributed vertically. We used reconstructed atmospheric forcing fields for 1850–2008 to perform an ocean climate simulation that adequately captures climatogical temperature and salinity profiles. Then, a water mass classification distinguishes three water masses corresponding to the classical view, warm and fresh surface waters, cold and fresh intermediate waters, and cold and salty bottom waters, and two transition water masses. The temperature trends show a similar three layers pattern with fast warming at the surface (~ 0.06 K decade− 1) and bottom (> 0.04 K decade− 1) and slow in the intermediate layers (< 0.04 K decade− 1). The slow warming in the intermediate layer is explained by both weakly warmed water winter convection and the summer surface thermocline isolating the intermediate layers. The warming in the deep layers is related to warm surface inflow from the North Sea and Baltic proper in the southern and northern Baltic Sea respectively. Furthermore, sensitivity experiments show that the warming magnitude is controlled by rising air temperature while the vertical distribution of heat gain is related to surface wind conditions. Finally, the North Atlantic Oscillation and Atlantic Multidecadal Oscillation are well correlated with the temperature minimum and thus modulate the magnitude of warming in the intermediate layers on shorter time scales. This study provides a new picture of the Baltic Sea's warming and suggests that this complexity is essential for understanding the influence of climate change on marine ecosystems. [ABSTRACT FROM AUTHOR]

Recently nitrogen-hydrogen compounds have successfully been applied as co-catalysts for mild conditions ammonia synthesis. Ca2NH was shown to act as a H2 sink during reaction, with H atoms from its lattice being incorporated into the NH3(g) product. Thus the ionic transport and diffusion properties of the N–H co-catalyst are fundamentally important to understanding and developing such syntheses. Here we show hydride ion conduction in these materials. Two distinct calcium nitride-hydride Ca2NH phases, prepared via different synthetic paths are found to show dramatically different properties. One phase (β) shows fast hydride ionic conduction properties (0.08 S/cm at 600 °C), on a par with the best binary ionic hydrides and 10 times higher than CaH2, whilst the other (α) is 100 times less conductive. An in situ combined analysis techniques reveals that the effective β-phase conducts ions via a vacancy-mediated phenomenon in which the charge carrier concentration is dependent on the ion concentration in the secondary site and by extension the vacancy concentration in the main site. The detailed structures of two calcium nitride-hydride phases (Ca2NH) are explored and connected to their respective ionic conductivity. These materials have previously been investigated as a co-catalysts/support material for ammonia synthesis. [ABSTRACT FROM AUTHOR]

Disordered decagonal Al[sub 72]Co[sub 16]Ni[sub 12] quasicrystals were investigated by recording diffuse neutron scattering at instruments D10 and IN8/ILL up to 1000 °C. This neutron work supplements X-ray-diffraction investigations, which do not provide a scattering contrast of the transition metals. Moreover, diffuse scattering of inelastic origin could be suppressed, within the resolution limits, by using an analyser. The temperature dependence of the diffuse scattering in the quasiperiodic plane indicates complex re-ordering processes. A one-dimensional superorder along the unique axis, reflected by diffuse layers perpendicular to it, dissolves at 950 °C; short-range-order maxima remain visible at 980 °C. [ABSTRACT FROM AUTHOR]

Iron is essential to cells as a cofactor in enzymes of respiration and replication, however without correct storage, iron leads to the formation of dangerous oxygen radicals. In yeast and plants, iron is transported into a membrane-bound vacuole by the vacuolar iron transporter (VIT). This transporter is conserved in the apicomplexan family of obligate intracellular parasites, including in Toxoplasma gondii. Here, we assess the role of VIT and iron storage in T. gondii. By deleting VIT, we find a slight growth defect in vitro, and iron hypersensitivity, confirming its essential role in parasite iron detoxification, which can be rescued by scavenging of oxygen radicals. We show VIT expression is regulated by iron at transcript and protein levels, and by altering VIT localization. In the absence of VIT, T. gondii responds by altering expression of iron metabolism genes and by increasing antioxidant protein catalase activity. We also show that iron detoxification has an important role both in parasite survival within macrophages and in virulence in a mouse model. Together, by demonstrating a critical role for VIT during iron detoxification in T. gondii, we reveal the importance of iron storage in the parasite and provide the first insight into the machinery involved. Iron is essential to cells, however without correct storage can lead to cell damage. Aghabi et al. show that the vacuolar iron transporter (VIT) is required for iron storage in the parasite Toxoplasma gondii. They find VIT protects against iron toxicity and has a role in parasite virulence. [ABSTRACT FROM AUTHOR]

Microsporidia are obligate intracellular parasites able to infect a wide range of hosts from invertebrates to vertebrates. The success of their invasion process is based on an original organelle, the polar tube, which is suddenly extruded from the spore to inoculate the sporoplasm into the host cytoplasm. The polar tube is mainly composed of proteins named polar tube proteins (PTPs). A comparative analysis allowed us to identify genes coding for 5 PTPs (PTP1 to PTP5) in the genome of the microsporidian Anncaliia algerae. While PTP1 and PTP2 are found on the whole polar tube, PTP3 is present in a large part of the extruded polar tube except at its end-terminal part. On the contrary, PTP4 is specifically detected at the end-terminal part of the polar tube. To complete PTPs repertoire, sequential sporal protein extractions were done with high concentration of reducing agents. In addition, a method to purify polar tubes was developed. Mass spectrometry analysis conducted on both samples led to the identification of a PTP3-like protein (PTP3b), and a new PTP (PTP7) only found at the extremity of the polar tube. The specific localization of PTPs asks the question of their roles in cell invasion processes used by A. algerae. [ABSTRACT FROM AUTHOR]

Chemiresistive sensors are promising devices for sensing hydrogen gas in a broad range of applications including fuel cells, hydrogen storage systems, petroleum refinement, and diagnosis of oil-insulated transformers. Herein, electrospun ZnO–SnO2 belts (BLs) were synthesized and applied as resistive-type sensing layers for hydrogen sensing. The ZnO–SnO2 BLs containing 20 mol% of Zn relative to Sn showed a response (Ra/Rg, Ra: resistance in air, Rg: resistance in target gas) of 6.7, fast response speed (3.6 s), and a distinguishable selectivity toward 5 ppm of hydrogen at 400 °C in the presence of formaldehyde, methane, ammonia, carbon monoxide, and carbon dioxide gases. The sensor displayed a repeatable response when subjected to 15 cycles of alternate air and 5 ppm hydrogen exposure. A unique hydrogen sensing performance of the BLs was attributed to their belt morphology, numerous surface pores, smaller crystal size, ZnO/SnO2 heterojunction, and ZnO metallization following hydrogen exposure. The present synthetic method paves the way for generating microstructures with smaller diffusion length that overcomes the shortcomings of non-porous and/or thick materials while providing a potential platform for reliable and enhanced hydrogen sensing. [ABSTRACT FROM AUTHOR]

This present study investigated the removal of COD and ammoniacal nitrogen (NH4+–N) from tannery deliming wastewater (TDLWW) through microbes immobilized carbon consisted a bioreactor (MICCR) and reactive struvite crystallization process. Initially, 90% of the organic content of TDLWW was removed using a MICCR reactor at 24 h retention time. Nanoporous carbon (NPC) was used as the carrier matrix for the MICCR reactor. SEM and AFM images of NPC used in the MICCR reactor identify different microorganisms on its surface. The microbial profile of NPC used in the MICCR was analyzed, and the relative abundance is phyla Firmicutes, 25.64%; Proteobacteria, 43.68%; Bacteroidetes, 6.58%; Cyanobacteria, 2.22%; Actinobacteria, 2.34% reason for organic removal. The removal of organics follows the pseudo-second-order rate kinetics with the rate constant of 1.75 × 10−3 L COD−1 h−1. For the reactive struvite crystallization, MgO and Na2HPO4.2H2O were taken as the precipitating agents. The optimum molar ratio for the maximum conversion of NH4+–N into struvite was obtained as 1:1.4:1.4 (NH4+–N:MgO:Na2HPO4.2H2O). The volume of struvite precipitate was 48.5 mL/L of TDLWW, and the dry weight was 8.89 g/L. More than 93% of NH4+–N was converted as the struvite fertilizer. The conversion of NH4+–N into struvite follows the pseudo-first-order rate kinetics with the rate constant of 1.67 × 10−2 min−1. Despite the conversion of NH4+–N into struvite, COD removal was observed, which confirms the conversion of organic nitrogen into struvite. The struvite was evaluated using SEM, XRD, TGA, DSC, and FT-IR spectroscopic analysis. Hence, the integrated MICCR and the reactive struvite crystallization process can be applied to manage tannery deliming wastewater. [ABSTRACT FROM AUTHOR]

Modern civilization has no collective experience with possible wide-ranging effects from a medium-sized asteroid impactor. Currently, modeling efforts that predict initial effects from a meteor impact or airburst provide needed information for initial preparation and evacuation plans, but longer-term cascading hazards are not typically considered. However, more common natural disasters, such as volcanic eruptions, earthquakes, wildfires, dust storms, and hurricanes, are likely analogs that can provide the scope and scale of these potential effects. These events, especially the larger events with cascading effects, are key for understanding the scope and complexity of mitigation, relief, and recovery efforts for a medium-sized asteroid impact event. This paper reviews the initial and cascading effects of these natural hazards, describes the state of the art for modeling these hazards, and discusses the relevance of these hazards to expected long-term effects of an asteroid impact. Emergency managers, resource managers and planners, and research scientists involved in mitigation and recovery efforts would likely derive significant benefit from a framework linking multiple hazard models to provide a seamless sequence of related forecasts. [ABSTRACT FROM AUTHOR]

Cold plasma is a partially ionized state of matter that unites high reactivity and mild conditions. Therefore, cold plasma reactors are intriguing for reaction engineering. In this work, a laboratory scale dielectric barrier discharge (DBD) cold plasma reactor was designed, set up, and used for studying the influence of the specific energy input (SEI) on the product spectrum of the partial oxidation of methane. In total, 23 experiments were carried out near ambient conditions with a molar reactant ratio of methane to oxygen of 2:1 at SEI between 0.3 and 6.0 J cm−3. The feed also contained argon at a mole fraction of 0.75 mol mol−1. The product stream was split into a fraction that was condensed in a cold trap and the remaining gaseous fraction. The latter was analyzed at-line in a gas chromatograph equipped with a dual column and two carrier gases. The condensed fraction was analyzed by qualitative and quantitative 1H and 13C NMR spectroscopy, Karl Fischer titration, and sodium sulfite titration. In the product stream, 16 components were identified and quantified: acetic acid, acetone, carbon dioxide, carbon monoxide, ethanol, ethane, ethene, ethylene glycol, formaldehyde, formic acid, hydrogen, methanol, methyl acetate, methyl hydroperoxide, methyl formate, and water. A univariant influence of the SEI on the conversions of methane and oxygen and the selectivities to the products was observed. The experimental results provided here are an asset for developing reaction kinetic models of the partial oxidation of methane in DBD plasma reactors. [ABSTRACT FROM AUTHOR]

CH4 sensors based on metal oxide semiconductors (MOS) provide high sensitivity and fast response, but the sensitivity will be lost when they are poisoned by silicone. Therefore, there is an urgent need to address the poisoning deactivation of MOS gas sensors caused by silicone. Here, the unique strategy of coating a reactive anti-poisoning material onto the surface of the sensing material is proposed to effectively improve the anti-poisoning ability without degrading the gas sensing performance. As an experimental verification, SnO2/α-Al2O3 is designed as the anti-poisoning layer and SnO2 loaded with precious metals (Pt and Pd) as the sensing layer. Owing to the protection of the anti-poisoning layer, the response (Ra/Rg = 24.69) and the response/recovery time (1/24 s) of the sensor to CH4 remained undiminished at 364 °C after being poisoned under an air/hexamethyldisiloxane (HMDSO) (10 ppm) environment for 40 min, which meets the requirements of the Chinese National Standard (GB 15322.2-2019). The mechanism analysis shows that HMDSO can be decomposed with the adsorbed oxygen on the surface of SnO2 in the anti-poisoning layer, and CH4 can diffuse into the sensing layer to be detected. The unique anti-poisoning strategies can provide a promising insight for improving the poisoning tolerance of MOS gas sensors. [ABSTRACT FROM AUTHOR]

The results of comparative analysis for the key factors of the mechanism of oil-recovery enhancement with the use of gases in a supercritical fluid state as applied to carbon dioxide and propane (propane/butane mixtures) are presented. The above-mentioned factors as a subject of consideration incorporate the dissolving ability of compressed gases with respect to oil and its components, the phase behavior of binary systems containing the mentioned displacing agents and oil hydrocarbons, the critical parameters for the binary systems of fluid-phase behavior types I–II, the compressibility of carbon dioxide and propane under oil-displacement process conditions in tertiary oil production, the viscosity of the media participating in the discussed process and, finally, the swelling of oil as a result of its saturation with a gas. The results of experimental implementation under supercritical fluid conditions are given for an extraction oil-recovery process with carbon dioxide as an extragent in one case and propane in the other case. It is established that propane and propane/butane mixtures are three or more times superior to CO2 in dissolving ability with respect to oil components under displacement-process conditions; that they more often form systems of fluid-phase behavior types I–II with the oil components, which is preferable for the process of its recovery; that the compressor power spent on the compression of carbon dioxide and methane is threefold or more higher than for propane; and, finally, that propane has a much lower viscosity under oil-displacement conditions. In sum, propane and propane/butane mixtures are preferable for use in the oil-displacement process within the framework of tertiary oil production. [ABSTRACT FROM AUTHOR]

In this study, a synthetic BaSO4·CaSO4 composite was prepared by co-precipitation technique, characterised and examined for REE sorption. The sorption parameters were; pH = 4, equilibrium time = 20 min, temperature = 303 K, and REE liquor volume to composite mass ratio of 0.2:1 L g−1. The sorption reaction was controlled by pseudo 2nd order kinetic mechanism and Langmuir adsorption isotherm with an adsorption capacity of 168.63 mg g−1. 90.14% of REE (III) was desorbed using 1 mol L−1 HNO3. The process was endothermic and spontaneous. Accordingly, 1:1 barite-gypsum (natural ingredient for BaSO4·CaSO4), with 136 mg g−1 loading capacity, was used for REEs extraction. [ABSTRACT FROM AUTHOR]