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Metal-support interface influences the catalytic activity and physical properties of heterocatalysts dramatically. Herein, the effect of cerium on material properties and catalytic activity of cobalt over gamma-alumina applied in dry reforming of methane (DRM) was investigated. The dispersion of cobalt over gamma-alumina was noticeably improved with low cerium dosages ranging from 0.1 to 0.5 wt%. In addition, the presence of Ce promoter on catalyst surface led to an enhancement in reducibility of cobalt oxide to cobalt metal in the catalyst activation. Using CO2-temperature programmed desorption technique, the catalyst basicity was found to increase proportionally with cerium loading. At an optimal dosage of 0.3–0.5 wt%, the cerium promoted cobalt supported on gamma catalyst displayed outstanding performance in DRM with noticeable conversion improvements up to 11% in both methane and carbon dioxide.

Rice husk is one of the most abundant biomass resources in the world, yet it is not effectively used. This study focuses on the sustainably rice-husk-extracted lignin, nano-lignin (n-Lignin), lignin-capped silver nanoparticles (LCSN), n-Lignin-capped silver nanoparticles (n-LCSN), and lignin-capped silica-silver nanoparticles (LCSSN), and using them for antibacterial activities. The final n-Lignin-based products had a sphere-like structure, of which the size varied between 50 and 80 nm. We found that while n-Lignin and lignin were less effective against Escherichia coli than against Staphylococcus aureus, n-Lignin/lignin-based hybrid materials, i.e., n-LCSN, LCSN, and LCSSN, were better against E. coli than against S. aureus. Interestingly, the antimicrobial behaviors of n-LCSNs could be further improved by decreasing the size of n-Lignin. Considering the facile, sustainable, and eco-friendly method that we have developed here, it is promising to use n-Lignin/lignin-based materials as highly efficient antimicrobials without environmental concerns.

Synthesis of tubulysin analogues, containing an N-methyl substituent on tubuvaline-amide together with the replacement of either the hydrophobic N-terminal N-methyl pipecolic acid (Mep) or at both N- and C- terminal peptides with available heteroaromatic acids and an unsaturated tubuphenylalanine moiety, respectively, were described. The in vitro cytotoxic activity by SRB assay on five cancer cell lines for sixteen tubulysins was evaluated. Among them, five analogues exhibited strong cytotoxic activities against five human cancer cell lines, including human breast carcinoma (MCF7), human colorectal adenocarcinoma (HT-29), HL-60, SW-480, human lung adenocarcinoma (A459). Interestingly, one analogue showed the strongest cytotoxicity on all five tested cell lines even much higher toxicity than the reference compound ellipticine.

Seven synthetic derivatives of ursolic acid, lupeol, and betulinic acid (1a–1b, 2a–2b, and 3a–3c) were synthesized to study their α-glucosidase inhibitory activity. Three of them (2b, 3b, and 3c) are new compounds. Among the synthetic derivatives, betulinic acid analogues 3b and 3c exhibited the best activity against α-glucosidase and is superior to the positive agent, with IC50 values of 35.0 ± 3.37 and 34.0 ± 1.24 μM, respectively.

The existence of chromium in hexavalent oxidation state is highly toxic to aquatic environment. Photocatalytic reduction of hexavalent Cr (VI) into Cr (III) has emerged as a desirable technology due to their prospect in solar energy utilization, high efficiency and low cost. Graphitic carbon nitride (g-C3N4)-based photocatalysts are ideal for Cr (VI) reduction due to their inherent features including; visible-light responsive narrow bandgap, suitable conduction band potential, high physicochemical stability, unique optical and electronic properties. Herein, various surface-interface strategies to modify g-C3N4 including heterojunction formation, doping, structural regulation, co-catalyst loading and construction of nitrogen vacancies are elaborated for improving the Cr(VI) photoreduction efficiency. The review also highlights the effect of operational reaction conditions such solution pH, g-C3N4 dosage, Cr (VI) concentration, temperature, light source, organic acid additives and co-existing ions influencing Cr (VI) reduction efficiency. Finally, we attempt to propose the existing issues based on the current research and future aspects of engineered g-C3N4 for Cr (VI) photoreduction.

Azole-resistant environmental Aspergillus fumigatus presents a threat to public health but the extent of this threat in Southeast Asia is poorly described. We conducted environmental surveillance in the Mekong Delta region of Vietnam, collecting air and ground samples across key land-use types, and determined antifungal susceptibilities of Aspergillus section Fumigati (ASF) isolates and azole concentrations in soils. Of 119 ASF isolates, 55% were resistant (or non-wild type) to itraconazole, 65% to posaconazole and 50% to voriconazole. Azole resistance was more frequent in A. fumigatus sensu stricto isolates (95%) than other ASF species (32%). Resistant isolates and agricultural azole residues were overrepresented in samples from cultivated land. cyp51A gene sequence analysis showed 38/56 resistant A. fumigatus sensu stricto isolates carried known resistance mutations, with TR34 /L98H most frequent (34/38).

This study proposes a photonic crystal fiber made of fused silica glass, with the core infiltrated with chloroform as a new source of supercontinuum (SC) spectrum. We numerically study the guiding properties of the fiber structure in terms of characteristic dispersion and mode area of the fundamental mode. Based on the results, we optimized the structural geometries of the CHCl3-core photonic crystal fiber to support the broadband SC generations. The fiber structure with a lattice constant of 1 μm, a filling factor of 0.8, and the diameter of the first-ring air holes equaling 0.5 μm operates in all-normal dispersion. The SC with a broadened spectral bandwidth of 0.64 to 1.80 μm is formed by using a pump pulse with a wavelength of 850 nm, 120 fs duration, and power of 0.833 kW. That fiber would be a good candidate for all-fiber SC sources as cost-effective alternative to glass core fibers.

Human milk lipids provide not only energy but also indispensable bioactive components such as essential fatty acids. To establish the recommended daily intake value and guidelines for infant formula, a reference library of fatty acid composition has been generated from 4 Asian countries (South Korea, China, Vietnam, and Pakistan). Regardless of country, palmitic acid (C16:0), linoleic acid (C18:1), and linolenic acid (C18:2) were the 3 most abundant fatty acids in human milk and account for more than 75% of total fatty acids (total FA). However, there were several considerable differences between fatty acids, particularly n-3 and n-6 (omega-3 and omega-6) groups. Chinese mothers' milk had a high concentration of linoleic acid at 24.38 ± 10.02% of total FA, which may be due to maternal diet. Among the 4 countries, Pakistani mothers' milk contained a high amount of saturated fatty acid (56.83 ± 5.96% of total FA), and consequently, polyunsaturated fatty acids, including n-3 and n-6, were significantly lower than in other countries. It is noteworthy that docosahexaenoic acid (DHA) in Pakistani mothers' milk was 44.8 ± 33.3 mg/L, which is only 25 to 30% of the levels in the other 3 countries, suggesting the need for DHA supplementation for infants in Pakistan. Moreover, the ratio of n-6 to n-3 was also remarkably high in Pakistani mothers' milk (15.21 ± 4.96), being 1.4- to 1.7-fold higher than in other countries. The average DHA:ARA ratio in Asian human milk was 1.01 ± 0.79. Korean mothers' milk showed a high DHA:ARA ratio, with a value of 1.30 ± 0.98, but Pakistani mothers' milk had a significantly lower value (0.42 ± 0.12). The fatty acid compositions and anthropometric data of mother (body mass index, age) did not show any correlation. The obtained data might provide information about human milk compositions in the Asian region that could benefit from setting up recommended nutrient intake and infant formula for Asian babies.

A Gram-stain-negative, rod-shaped, aerobic and non-motile bacterium, designated P2-65T, was isolated from Moonsan stream water in the Republic of Korea. The temperature, NaCl concentration and pH ranges for growth of strain P2-65T were 10–37 °C, 0.0–3.0% (w/v) and 6.5–8.5 with optimum growth at 25–30 °C, 0.0–1.0% and 7.0–7.5, respectively. Comparison of 16S rRNA gene sequence showed that strain P2-65T was closely related to Flavobacterium cauense (95.4%) and Flavobacterium cheniae (95.3%). The major fatty acids were iso-C15:0, iso C17:0 3-OH, summed feature 3 (C16:1ω7c and/or C16:1ω6c), summed feature 9 (iso-C17:1 ω9c and/or 10-methyl C16:0) and iso-C15:0 3-OH. The predominant respiratory quinone was menaquinone-6 (MK-6). The major polar lipids detected in the strain were phosphatidylethanolamine, one aminophospholipid, one unidentified aminolipid and one unidentified polar lipid. The G + C content of the genomic DNA was 39.7%. The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values for strain P2-65T with closely related Flavobacterium species were below 74.8% and 20%, respectively. Based on polyphasic features, strain P2-65T is considered to represent a novel species of the genus Flavobacterium, for which the name Flavobacterium inviolabile sp. nov. is proposed. The type strain is P2-65T (= KCTC 62055T = NBRC 112953T).

Indian traditional medicinal plants are important sources of phytotherapeutic agents. Plants with antimicrobial properties have been involved in the treatment of infectious diseases and also, in mitigating the side effects produced by the synthetic antimicrobial agents. Hence, the present work has been focused on the study the antimicrobial activity of Thespesia populnea extract-coated nano-zirconium on cotton gauze fabrics. UV–Vis spectroscopy showed the strong peaks produced by Zr nanoparticle after 200 nm, which indicated that T. populnea-coated Zr nanoparticles would possess antimicrobial activity. The crystalline nature of the nanoparticles was confirmed by XRD analysis and the smaller size of the nanoparticles about 10 nm was observed using TEM analysis. The antimicrobial activity of T. populnea extract-coated Zr nanoparticles was studied by well diffusion against pathogens such as E. coli, Bacillus subtilis, Staphylococcus aureus and Pseudomonas aeruginosa and the Zr nanoparticles showed a high toxicity against the bacterial species studied. The antimicrobial activity suggests that the synthesized nanoparticles can be used in wounds dressings.

The impact of La2O3 promoter loading on alumina-supported cobalt catalysts was investigated in terms of physicochemical properties and catalytic performance for CO2 reforming of methane (CRM) at stoichiometric CH4/CO2 ratio and 1023 K. Both Co3O4 (with crystal size: 5.2–8.4 nm) and La2O3 nanoparticles were finely dispersed on support surface. The promotional La2O3 effect could noticeably increase CH4 and CO2 conversions to 29.3% and 17.3%, correspondingly due to improved basic site concentration and decreasing crystallite size of active metal in association with promoter addition. 5%La loading was an optimal promoter content for reactant conversions as well as yield of H2 and CO. 5%La-10%Co/Al2O3 also exhibited the highest resistance to carbon deposition owing to the basic nature, redox feature and oxygen vacancy of La2O3 dopant. Notably, the H2/CO ratio obtained within 0.84–0.98 is preferable for Fischer-Tropsch reaction in downstream to yield liquid hydrocarbon fuels.

Three types of biomass of invasive plants and agrowastes, namely, the wattle bark of Acacia auriculiformis (BA), mimosa (BM), and coffee husks (BC), were converted into biochars through slow pyrolysis and investigated for their ability to remove dyes in water. The properties of the materials were characterized using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) analysis. The BET surface area (total pore volume) of BC was 2.62 m2/g (0.007 cm3/g), far below those of BA and BM with 393.15 cm2/g (0.195 m3/g) and 285.53 cm2/g (0.153 m3/g), respectively. The optimal adsorption doses for the removal of methylene blue (MB) were found to be 2, 5, and 5 g/L for BC, BA, and BM, respectively. The suitable pH ranges for MB removal were 6–12 for BA, 7–12 for BC, and 2–10 for BM. The majority of MB (over 83%) was removed in the initial 30 min, followed by a more quasisteady state condition after the removal rate exceeded 90%. The experimental data were fitted with the kinetic models (PFO, PSO, Bangham, IDP), indicating that physicochemical adsorption, pore diffusion process, and multiple stages are the dominant mechanisms for the MB adsorption onto biochars. Finally, BA and BM showed similar adsorption efficiencies, while BC may not be favorable for use as an adsorbent due to its low surface area and low pore volume.

Five titanium-based alloys containing 4, 8, 12, 16, and 20 wt% molybdenum additive were fabricated by spark plasma sintering process at 1200 ˚C. The samples were scrutinized in terms of relative density, phase evolution, and microstructural development. The relative density reached 99.9% with the molybdenum addition up to 16 wt% but slightly dropped in the sample with 20 wt% additive. In the specimens with 4 wt% Mo, molybdenum solved completely in the matrix and three different phase morphologies were observed, namely continuous α-Ti, laminar α-Ti, and very thin laminar β-Ti. With increasing Mo content to 20 wt%, widespread single β-Ti appeared alongside remained Mo and α-Ti. Ductile fracture mode was dominant in the samples with low Mo contents whilst it changed to brittle in the specimens with higher content of molybdenum.

Climate change, global warming, and population growth have led researchers to use eco-sociable procedures for the N2 reduction reaction. It has discovered that N2 molecule can be transformed into NH3 in ambient circumstances with nanocomposites upon visible irradiation. In this research paper, a new visible-light-driven photocatalyst was constructed, with various weight percents of FeOCl particles (10, 20, 30, and 40%) that have adhered on NS-CN. Subsequently, multiple features of the nanocomposites were assayed in detail. The results illustrated that the NS-CN/FeOCl (20%) system has remarkable photoactivity in the NH4+ production reaction in comparison with the NS-CN and CN, which showed 2.5 and 8.6 higher activity, respectively. The durability of NS-CN/FeOCl (20%) system, as a substantial factor, was assayed for 5 recycles. Moreover, the effect of electron quenchers, pH of media, and solvent was studied. At last, a feasible Z-scheme mechanism for the remarkable improvement of N2 fixation efficiency was offered.

Hybrid composite TiO2/reduced graphene oxide (TiO2/rGO) is considered as a potential photoanode for dye-sensitized solar cells (DSSC) due to their excellent charge transport. This work aimed to prepare the composite TiO2/rGO from TiO2 and GO via a facile reduction step by ascorbic acid and annealing step at 450 °C. Incorporation 1%wt rGO into TiO2 photoanode can boost the overall performance of DSSC with the photocurrent of 13.5 mA/cm2 and the efficiency of 6.1% which is 37% enhanced than the bare TiO2 photoanode. The XPS, Raman spectroscopy and FT–IR results revealed the formation of the chemical bonding titania–carbon in composites TiO2/rGO-1% by ex-situ preparation. The interfacial charge transfer through chemical bonds significantly improves the photoelectrons transport and suppresses the recombination of electron holes in TiO2 structure.

The impact of Si3N4 and SiC additives incorporation in the microstructure and sintering behavior of TiB2-based composites were studied. Three ceramic composites including TiB2–Si3N4, TiB2–SiC, and TiB2–SiC–Si3N4 were manufactured by spark plasma sintering (SPS) at 1950 °C for 8 min under 35 MPa. The acquired ceramics were analyzed by X-ray diffractometry and scanning electron microscopy. In addition, the sintering thermodynamic was investigated using the HSC Chemistry package. X-ray diffraction patterns of the prepared ceramics revealed the in-situ formation of graphite and boron nitride in the final composites initiated from SiC and Si3N4, respectively. The thermodynamic assessments proved the role of liquid phase sintering on the sinterability enhancement of all composite samples. Field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy verified the in-situ formation of both BN and graphite components in the sample containing SiC and Si3N4 additives. Finally, the fractographical investigations clarified the transgranular breakage as the main fracture mode in the TiB2-based ceramics.

In this work, we proposed a facile approach to fabricate a superhydrophobic surface for anti-icing performance in terms of adhesive strength and freezing time. A hierarchical structure was generated on as-received Al plates using a wet etching method and followed with a low energy chemical compound coating. Surfaces after treatment exhibited the great water repellent properties with a high contact angle and extremely low sliding angle. An anti-icing investigation was carried out by using a custom-built apparatus and demonstrated the expected low adhesion and freezing time for icephobic applications. In addition, we proposed a model for calculating the freezing time. The experimented results were compared with theoretical calculation and demonstrated the good agreement, illustrating the importance of theoretical contribution in design icephobic surfaces. Therefore, this study provides a guideline for the understanding of icing phenomena and designing of icephobic surfaces.

This study deals with the preparation and characterization of platinum/reduced graphene oxide (Pt/rGO) as an efficient cathode for dye-sensitized solar cells. Herein, the Pt/rGO material was synthesized by co-precipitation from hexachloroplatinic acid (H2PtCl6) and graphene oxide (GO) precursors. The fabrication of cathodes from Pt/rGO composite paste was carried out using screen-printing paste. The electrochemical behaviors of as-prepared cathodes were analyzed by cyclic voltammetry; the performance of fabricated DSSCs was measured by current density–voltage (J-V) curves and electrochemical impedance spectroscopy. The structural characteristics of the Pt/rGO binary composites were confirmed by Fourier-transform infrared spectroscopy, Raman spectroscopy, x-ray diffraction (XRD), and transmission electron microscopy. Empirical data showed that choosing ascorbic acid as a reducing agent at a ratio of 5:1 between ascorbic acid weight and precursor mixture weight, as well as a GO weight percentage of 20% fabricated DSSCs successfully with a conversion efficiency of 6.25%, which was approximately 90% compared to that of pure commercial Pt material. Characterization results indicated that the Pt nanoparticles were homogeneously distributed on the rGO sheets with an average diameter of less than 25 nm. The Pt/rGO hybrid composite is highly expected to replace Pt in the fabrication of cathodes in DSSCs for low-cost DSSC production in the promising future.

Nylon 66, which is an important membrane class used in manufacturing of chitin and chitosan, have a number of features that can be improved by surface functionalizations into a novel composite structure with support of ultrasound and silica gel (SiG) catalyst in a doubled amidation reaction. Firstly, nylon 66/para-phenylenediamine thin film composite (NP-TFC) is prepared from commercial nylon 66 membrane in an ultrasound assisted hydrolysis-amidation reaction. Secondly, carboxylic functionalized multi-walled carbon nanotubes (MWCNT-COOH) are grafted on the NP fiber in an ultrasound assisted/SiG-catalyzed amidation reaction, where para-phenylenediamine (pPD) role is cross-linking. As an excellent result confirmed by either Fourier transform infrared (FTIR), Raman spectrometry or scanning electron microscopic (SEM), bundled MWCNTs bridges are easily built in SiG-catalyzed ethanol media to connect nylon 66 fibers at distances of 0.3–1 μm. The vacuum filtration test confirmed that as-prepared nylon 66/pPD/MWCNTs structure has superior Ca2+ rejection efficiency to that of original nylon 66.

The thrust of finding an alternative and noble metal free counter electrode (CE) for dye sensitized solar cells (DSSCs) encouraged the present study on new and unique structure of vanadium nitride nanopetals as counter electrode for DSSCs. Template-free vanadium nitride nanopetals were successfully synthesized by high temperature ammonia treatment of the precursor material viz. V2O5/melamine. The material analysis reveals the formation of highly crystalline vanadium nitride with mesoporous crosslinked intertwined nanopetals with pronounced electrocatalytic active sites leading to an excellent catalytic performance towards iodide/triiodide electrolyte, fast charge transfer kinetics, electron diffusion and low charge transfer resistance. The fabricated dye sensitized solar cell sandwiched with N719 dye loaded photoanode and VN nanopetals CE with an injection of iodide/triiodide electrolyte showed a significant power conversion efficiency (PCE) of 7.44%, which is higher than Pt CE (7.38%) under the same testing conditions. Results thus proved that the material is a promising candidate as an alternative counter electrode for Pt in DSSC.

This study aims at producing exopolysaccharides (EPS) from a lactic acid bacterial strain. The soybean whey-isolated Lactobacillus plantarum W1 (EPS-W1), which belongs to genus Lactobacillus, is identified using the phenylalanyl-tRNA sequencing method. Of all the examined strains, R-49778 (as numbered by BCCM/LMG Bacteria Collection, Ghent University, Belgium) showed the highest capability of producing exopoly-saccharides. Structural characterization revealed a novel exopolysaccharide consisting of repeating units of -> 6)-D-Glcp-(1 ->; -> 3)-D-Manp-(1 ->; -> 3)-6-Glcp-(1 -> and a branch of -> 6)-D-Manp-(1 ->; -> 2)-D-Glcp-(1 ->. This discovery opens up avenues for the production of EPS for food industries, functional foods, and biomedical applications.

In this study, a graphite and h-BN added TiC-based ceramic was produced by spark plasma sintering at 1900 °C. The sinterability of the graphite-doped sample could be improved, because undesirable TiO2 oxide layers were generally eliminated at the temperature of ~1300 °C. However, the co-addition of graphite and h-BN additives simultaneously had a destructive impact on the relative density of TiC because of the entrapped produced gases in the sintered composite at the high sintering temperature. According to the results, the introduced h-BN was partially reacted with the TiC/TiO2 compounds, forming in-situ TiB2 and TiB phases. The sample doped with graphite presented the most significant strength (over 630 MPa) where the relative density, grain size, and dispersion of the secondary phases were found as the influential factors. Finally, the highest coefficient of friction (~0.33) was achieved for the TiC-graphite specimen due to the distribution of the graphite with weak bonding within the TiC matrix.

The presence of hydrogen sulfide (H2S) in biogas negatively affects human health and corrodes metal. Therefore, the removal of H2S from biogas before using is an essential requirement in many cases. Recently, biotrickling filters (BTFs) have been widely applied to the treatment of H2S on both laboratory and industrial scales. However, BTFs method also has some drawbacks such as low mass transfer efficiency, clogging the bed filter due to further elemental sulfur (S) excess accumulation, and biogas dilution. This paper reviews the recent development of aerobic BTF systems and solutions for those limitations during the H2S oxidation process in biogas. In addition, the factors affecting H2S removal efficiency, including sulfur-oxidizing bacteria, biofilm, packing material, pH, dissolved oxygen (DO), empty bed retention time (EBRT), ingredients of nutrients for the growth of bacteria, trickling liquid and gas velocity, are also discussed. Finally, the current strength of research in the field of H2S removal in biogas using BTF and its future prospects are also suggested. Some of highest elimination capacity (EC) of 78.57 g H2S/m3h, 144 g H2S/m3h, 228.6 g H2S/m3h were obtained from previous experiments.

Novel TiC-based composites were produced by incorporating ZrN and carbon black additives to improve their flexural strength. Spark plasma sintering method at 1900 °C was implemented to fabricate the designed composites; i.e., monolithic TiC, TiC-5 wt% carbon black, TiC-5 wt% ZrN, and TiC-5 wt% carbon black-5 wt% ZrN. Carbon black enhanced the sintering behavior of TiC remarkably, whereas the introduction of ZrN altered the composition of the matrix. The applied ZrN and its inevitable oxide phase proportion (ZrO2) participated in the in-situ formation of ZrC and TiN compounds. Although ZrC was mainly entrapped in the carbonaceous phase, the remaining ZrN and TiN could be dissolved in the TiCx matrix, forming (Ti,Zr) (C,N) solid solution. As the mobility of dislocations is not plausible in the solid solution, TiC–ZrN-carbon black composite represented a higher flexural strength (741 MPa) than TiC-carbon black (658 MPa) counterpart. Furthermore, remarkable thermal conductivity (25.1 W/mK) and hardness (3233 HV0.1 kg) were achieved for the ceramic containing carbon black.

Micropropagation of rose (Rosa hybrida L. ‘Baby Love’) often encounter some abnormal phenomena such as yellow and abscission leaf, hyperhydricity, etc. These phenomena effect on the quality of shoots cultured in vitro as well as the survival rate of plantlets after transferred to greenhouse. This is due to the accumulation of ethylene in culture vessel, which leads to an increase in enzyme activity of cellulase and pectinase resulted in disrupting the cell wall binding and inducing organ abscission. In this study, the effect of silver nanoparticles (AgNPs) to overcome these abnormal phenomena as well as its effect on the growth and development of shoots and plantlets in rose cultured in vitro were evaluated. The results showed that after 6 weeks of shoot culture, the medium supplemented with 2 ppm AgNPs was the most suitable for in vitro shoot multiplication with the highest number of shoots/explant (6.67 shoots), shoot height (3.06 cm), fresh weight (451.00 mg), dry weight (58.33 mg), SPAD (32.28) and dry mass ratio(12.33%). Adding 3 ppm AgNPs into in vitro rooting medium may improve the growth and develop involve in plant height (3.06 cm), number of leaves (6.33), leaf length (1.50 cm), leaf width (1.50 cm), fresh weight (137.67 mg), dry weight (13.00 mg), number of roots (4.33), SPAD (39.37), dry mass ratio (9.40%) of rose plantlet after 4 weeks of culture. After treatment with AgNPs, the abnormal phenomena including ethylene gas accumulation (0.30 ppm), cellulase enzyme activity (0.14 UI/mL) and pectinase enzyme activity (0.40 UI/mL) was reduced compare with the other treatments and the control. In addition, the high survival rate (93.33%) of plantlets was also observed after 4 weeks transferred to greenhouse. On the other hand, the treatment with 5 ppm AgNPs also induced early rose in vitro flowering; however, when using AgNPs at high concentrations (7 ppm) inhibited growth, development, toxicity and even death of explants.

Rice is one of the most important crops but its productivity is severely threatened by both biotic and abiotic stresses. Jasmonic acid and its derivatives (referred to JA) are the lipid-based plant hormones that were commonly known as regulators of plant growth, development and defense responses. In this study, we compare the physiological and molecular responses of two rice accessions, G38 (Nep_nuong) and G11 (Tam-tron) to JA treatment. G38 plants under JA treatment experienced a reduction in shoot length, root weight, shoot weight and total plant weight which suggested its sensitiveness to JA, whereas G11 plants showed a less reduction in these traits. The expression levels of 12 JA-related genes were investigated in order to better understand how the JA biosynthesis and responses differ in these two contrasting rice accessions. A significantly higher expression level of a set of genes related to JA biosynthesis, signaling and response in G11 compare to G38 was observed. Furthermore, the inorganic phosphorus starvation (Pi) response was also examined in the two varieties G11 and G38. In low Pi condition (40 µM), G11 plants showed more roots, longer root length and shoot length, higher weight compared to the G38 plants which suggest that G11 did not suffer much effect of Pi deficiency. This study highlights the differences in JA growth response in 2 contrasting rice genotypes and also suggests the link between JA developmental response and the tolerance to the Pi starvation condition in rice.

Perovskite oxides have attracted significant attention as frontier materials for wide range of applications, such as electronic and energy storage and generation. The utilization of perovskite oxides as catalysts for photocatalytic water splitting has been intensively investigated owing to their excellent absorption, bandgap tunability, and good stability. They can be synthesized at a large scale using a solution process. In this study, considering the importance of perovskite oxide in the generation of clean energy in the near future, we summarize and discuss the most recent advances in the development of fabrication methods, surface modification, and structural engineering to achieve high catalytic activity and practical applicability for hydrogen evolution reaction (HER). Furthermore, the challenges and future scope associated with the development of perovskite for photocatalytic generation of hydrogen are discussed.

Increasing discharge and inadequate removal of pharmaceutical compounds pose significant concerns over global aquatic systems and human health. The accomplishment of affordable and safe water requires a stringent elimination of these micropollutants. This study evaluated the performance of Visible/N-doped TiO2 and Visible/N-doped TiO2/H2O2 processes using a submerged photocatalytic membrane reactor (SMPR) with suspended N-doped TiO2 to address the removal of diclofenac (DCF). The kinetic and pathway of photodegradation of DCF were of particular interest in this study. The initial DCF concentrations upon the experiments were also examined using a wide range of 5–50 mg/L and 20–100 mg L−1 for Vis/N-doped TiO2, and Vis/N-doped TiO2/H2O2 process, respectively. The results indicated that higher initial concentration reduces the efficiency of the process, but one with H2O2 demonstrated an enhanced performance. The experimental data were found to fit well a pseudo-first-order kinetic model. Our findings demonstrated the analogous pathways of DCF for both processes. The Vis/N-doped TiO2/H2O2 process tends to hasten the degradation rate as evidenced by the disappearance of some DCF byproducts at a similar irradiation period as compared to the other. The study provided useful information of the degradation rate and the potential formation of DCF intermediates upon the hybrid photocatalytic systems, therefore being of importance for scaling-up as well as evaluating potential detoxification of DCF upon the novel photocatalytic system.

In this study, the spark plasma sintering technology was implemented to produce hybrid zirconium diboride ceramics comprising of silicon carbide whiskers (SiCw: 25 vol%) and various amounts of graphene nano-platelets (Gnp: 0–7.5 wt%). The effects of nano-graphene addition on the structural evolution, hardness, fracture toughness, and densification behavior of ZrB2–SiCw nanocomposites were investigated. Though all produced hybrid ceramics reached the full densification level, with relative densities of ≥99.9%, a negligible drop was observed in the relative density of the specimen reinforced with 7.5 wt% graphene nano-platelets. After the sintering step and due to the lack of any chemical interaction in the ZrB2–Gnp–SiCw system, no in-situ formed phases were detected by X-ray diffraction or electron microscopy investigations. The incorporation of nano-scale graphene additives resulted in grain coarsening inhibition significantly. The hardness slightly increased from 21.9 GPa for the specimen with no graphene to 22.2 GPa for the sample doped with 2.5 wt% graphene. However, with rising the nano-graphene amount, the hardness remarkably dropped to 16.6 GPa and 19.1 GPa for the samples doped with 7.5 wt% and 5 wt% nano-graphene, respectively. The fracture toughness remarkably enhanced, with a linear trend, by the addition of graphene nano-platelets from lower 5 MPa m½ in the carbon-free ceramic to above 6 MPa m½ in the specimen doped with 7.5 wt% nano-graphene. The identified dominant toughening mechanisms were crack bridging, crack arresting, and crack deflection.

Porous organic polymers (POPs) constructed through covalent bonds have raised tremendous research interest because of their suitability to develop robust catalysts and their successful production with improved efficiency. In this work, we have designed and explored the properties and catalytic activity of a template-free-constructed, hydroxy (-OH) group-enriched porous organic polymer (Ph-POP) bearing functional Pd nanoparticles (Pd-NPs) by one-pot condensation of phloroglucinol (1,3,5-trihydroxybenzene) and terephthalaldehyde followed by solid-phase reduction with H2. The encapsulated Pd-NPs rested within well-defined POP nanocages and remained undisturbed from aggregation and leaching. This polymer hybrid nanocage Pd@Ph-POP is found to enable efficient liquid-phase hydrodeoxygenation (HDO) of acetophenone (AP) with high selectivity (99%) of ethylbenzene (EB) and better activity than its Pd@Al2O3 counterpart. Our investigation demonstrates a facile, scalable, catalyst-template-free methodology for developing novel porous organic polymer catalysts and next-generation efficient greener chemical processes from platform molecules to produce value-added chemicals. With the aid of comprehensive in situ ATR-IR spectroscopy experiments, it is suggested that EB can be more easily desorbed in a solution, reflecting from the much weaker but better-resolved signal at 1494 cm-1 in Pd@Ph-POP compared to that in Pd@Al2O3, which is the key determining factor in favoring an efficient catalytic mechanism. Density functional theory (DFT) calculations were performed to illustrate the detailed reaction network and explain the high catalytic activity observed for the fabricated Pd@Ph-POP catalyst in the HDO conversion of AP to EB. All of the hydrogenation routes, including direct hydrogenation by surface hydrogen, hydrogen transfer, and the keto-enol pathway, are evaluated, providing insights into the experimental observations. The presence of phenolic hydroxyl groups in the Ph-POP frame structure facilitates the hydrogen-shuttling mechanism for dehydration from the intermediate phenylethanol, which was identified as a crucial step for the formation of the final product ethylbenzene. Besides, weaker binding of the desired product ethylbenzene and lower coverage of surface hydrogen atoms on Pd@Ph-POP both contributed to inhibiting the overhydrogenation reaction and explained well the high yield of EB produced during the HDO conversion of AP on Pd@Ph-POP in this study.

In the present study, we incorporated AlN (5 wt%) with TiB2 ceramic and consolidated the mixture by relatively low temperature sintering method, resulting in a near fully dense composite. Monolithic TiB2 and TiB2–AlN (5 wt%) were manufactured by spark plasma sintering (SPS) at 1900 °C for 7 min under 40 MPa. The prepared composites were precisely characterized by field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) analyses. In addition, possible chemical reactions during the sintering process were thermodynamically assessed using the HSC Chemistry software. The addition of AlN influenced the sinterability of titanium diboride, yielding a relative density of 99.7%. XRD results revealed the in-situ formation of h-BN during the sintering, whereas thermodynamic studies suggested the formation of both Al2O3 and h-BN. Furthermore, the microstructural investigation verified the synthesis of both Al2O3 and h-BN phases. Finally, the fractographical study revealed the effective role of AlN additive for refining the microstructure of TiB2.

In this work, the CNNS/Ag/AgFeO2 photocatalysts were synthesized by the thermal polymerization-hydrothermal method, aiming for photocatalytic degradation of RhB under visible irradiation. Different advanced techniques such as X-ray diffraction analysis (XRD), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), Total Organic Carbon (TOC) analysis, and so on were employed to examine samples features. The results showed that the CNNS/Ag/AgFeO2 (15%) photocatalyst possess a higher potential for rhodamine B (RhB) photodegradation than pure CN and CNNS photocatalysts. The rate constant of CNNS/Ag/AgFeO2 (15%) (957x10(-4) min(-1)) is 55 and 5.8 times higher than of pure CN (17.3 x 10(-4) min(-1)) and CNNS (164x10(-4) min(-1)) photocatalysts, respectively. The reasons for the better photocatalytic performance of prepared nanocomposites can be attributed to the synergistic effect between CNNS and Ag/AgFeO2. Therefore, the ability of visible light absorption and separation of photogenerated electron-hole pairs are effectively increased. A photocatalytic mechanism was presented, and suppressing the recombination of photogenerated charges resulting from the formation of the Z-scheme heterojunction was discussed. The prepared nanocomposite's photocatalytic performance for malachite green (MG), methyl orange (MO), and congo red (CR) degradation as organic dyes and phenol as a colorless pollutant were studied. Besides, after four photocatalytic cycles, there was no significant inactivity, indicating acceptable stability of the investigated nanocomposite. (c) 2020 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

This study aims to investigate the impact of zirconium nitride (ZrN) additive on the microstructural features and physical-mechanical characteristics of TiC. For this objective, two different samples, namely monolithic TiC and TiC-5 wt% ZrN, were produced by spark plasma sintering method at 1900 °C for 10 min under 40 MPa. X-ray diffraction, field emission scanning electron microscopy, and thermodynamical evaluations confirmed the formation of a single solid solution of (Ti,Zr)(C,N), along with a carbon-rich secondary phase in the doped ceramic. The monolithic TiC provided a higher relative density (95.5%) than the ZrN-doped sample. The fractographical assessment revealed a change in the fracture mode of TiC from transgranular to intergranular with introducing the ZrN additive. Reinforcing TiC with ZrN resulted in a Vickers hardness of 2640 HV0.1 kg, a flexural strength of 444 MPa, and a thermal conductivity of 14.9 W/mK. Furthermore, the TiC–ZrN sample presented a higher coefficient of friction (0.37 on average) compared to the monolithic TiC (0.34 on average).

A submerged photocatalytic membrane reactor (SPMR) was used with suspended and immobilized N–TiO2 under visible irradiation for diclofenac (DCF) removal from wastewater. The effects of initial N–TiO2 concentrations for the SPMR with suspended N–TiO2 were determined for batch processes. Hydrogen peroxide was also coupled with the photocatalytic process. In continuous conditions, a reverse osmosis (RO) membrane was combined with the SPMR for enhancing effluent quality. DCF removal by the SPMR with suspended and immobilized N–TiO2 at a low N–TiO2 dosage (0.5 g/L) was not much different between the two systems, but increased with higher N–TiO2 dosages for the reactor with suspended N–TiO2. Coupling H2O2 with the photocatalytic process under visible irradiation enhanced the DCF removal efficiency. In continuous conditions, DCF concentrations in the photoreactor increased during the reaction time, while those in the effluent (RO permeate) were steady for both systems and both processes. The permeate flux in the reactor with suspended N–TiO2 declined faster than in the reactor with the immobilized N–TiO2. Coupling H2O2 with the photocatalytic process yielded more resistant permeate flux rates. The cake layer formed on the microfiltration membrane of the SPMR with suspended N–TiO2 under visible irradiation was denser than others after completing the process.

Electrochemical carbon dioxide (CO2) reduction powered by renewable electricity offers a path to produce valuable products from CO2 —this earth-scale human waste— and to store intermittent renewable energy in the form of chemical fuels. Recently, single metal atoms (SMAs) immobilized on a conductive substrate have been shown as effective catalysts for the electrochemical CO2 reduction, opening the door to a new generation of low-cost and high-performance catalysts for fuel and chemical production. The unique physical and chemical properties of a single-atomic structure, the homogeneity of the active sites, combined with tunable coordination environment are essential for realizing highly active and selective catalysts. In this review, we focus on the structure-performance relationship in SMA catalysts for CO2 reduction from both theoretical and experimental aspects. We discuss why SMA catalysts exhibit distinct catalytic performance compared to their counterpart nanoparticles. Recent strategies for improving the CO2 reduction selectivity and activity by tuning the nature and coordination environment of SMA active sites are described. Finally, we highlight potential applications of SMA catalysts in practical CO2 reduction conditions, critical challenges and the path toward efficient electrochemical CO2 reduction catalysis based on SMAs.

The promotional La2O3 effect on the physicochemical features of mesoporous alumina (MA) supported cobalt catalyst and its catalytic performance for methane dry reforming (MDR) was examined at varied temperature and stoichiometry feedstock. The Co3O4 nanoparticles were evidently scattered on fibrous mesoporous alumina with small crystal size of 8–10 nm. The promotion behavior of La2O3 facilitated H2-reduction by providing higher electron density and enhanced oxygen vacancy in 10%Co/MA. The addition of La2O3 could reduce the apparent activation energy of CH4 consumption; hence, increasing CH4 conversion up to 93.7% at 1073 K. The enhancement of catalytic activity with La2O3 addition was also due to smaller crystallite size, alleviated H2-reduction and the basic character of La2O3. Lanthanum dioxycarbonate transitional phase formed in situ during MDR was accountable for mitigating deposited carbon via redox cycle for 17–30% relying on reaction temperature. Additionally, the oxygen vacancy degree increased to 73.3% with La2O3 promotion. The variation of H2/CO ratios within 0.63–0.99 was preferred for downstream generation of long-chain olefinic hydrocarbons.

This investigation intends to study the influence of titanium nitride (TiN) additive on the sintering behavior, mechanical features and microstructural development of TiC-based substances. For this objective, two different samples, namely monolithic TiC and TiC-5 wt% TiN, were sintered at 1900 °C using the SPS method. The specimens were held at the ultimate temperature for 10 min under 40 MPa. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) were implemented to characterize the as-produced specimens. Introducing TiN increased the relative density of TiC by around 1.5%, standing next to 97%. The assessments revealed the creation of non-stoichiometric TiC1-x along with some graphitized carbon phases in the undoped ceramic. By contrast, TiN additive completely dissolved into the TiC matrix in the composite sample and a new in-situ phase (C3N4) appeared. Finally, a Vickers hardness of ~2750 HV0.1 and a flexural strength of ~450 MPa were achieved for the TiN-doped specimen.

This study presents a greener approach to fabricate mixed matrix membranes (MMMs) by introducing malachite nanoparticles (MLC NPs) synthesized from copper sulfate, a toxic waste from many industrial applications, into polyethersulfone (PES) membrane to remove organic matter for water reclamation. The PES/MLC MMMs were characterized by XRD, FTIR, SEM(EDX), Raman Spectroscopy, Photoluminescence Spectrometry, and Contact angle measurements. Results showed that the incorporation of MLC NPs into PES altered the membrane morphology, and made the membrane more hydrophilic. At the optimal amount of 0.1 wt.% MLC NPs, PES/MLC showed the best water flux of 931.1 L/(m2 h) (LMH) with the highest breaking stability of 5.06 ± 0.33 MPa. The membrane also exhibited enhanced adsorption of organic foulants with a corresponding flux recovery rate of 0.55 ± 0.03%. The inevitable agglomeration of MLC NPs witnessed at MLC NP dosage of 1 wt.% compromised either the throughput or the mechanical integrity. The elevated NP loading rate from 0 to 1 wt.% enhanced the removal rate of organic carbon (C) from 20.8 ± 1.7% to 26.3 ± 2.3%, respectively. Optical methods demonstrated the preferential rejection of aromatic constituents by the fabricated membranes suggests their potential applicability of optical methods, particularly the fluorescence spectrometry for better prediction of treated water quality by membrane filtration.

Recent experimental studies have often described the interface of the graphene/semiconductor (G/S) junction in terms of conventional metal/semiconductor (M/S) contact models, but the details of the...

Recovery of functional iron-binding protein hydrolysate from Acetes japonicus employing enzymatic hydrolysis and iron-chelating peptide identification were conducted in this study. The result showed that under the optimal hydrolysis condition including Flavourzyme, pH 5, 50 °C, E:S ratio of 27.4 U/g protein and hydrolysis time of 4.8 h, the obtained proteolysate displayed the maximal iron-binding capacity (IBC) of 177.7 μgFe2+/g protein and comprehended 38,77 % of essential amino acids. Functional features of the Acetes proteolysate encompassing solubility, heat stability, foaming and emulsifying property, oil and water holding capacity were also noteworthy. Peptide fractionation was performed using ultrafiltration and the 1−3 kDa fraction expressed the highest IBC of 120.43 ± 0.15 μgFe2+/g protein, 13.7 times lower than that of disodium ethylenediaminetetraacetate (Na2EDTA). From this fraction, two iron-binding peptides of DSVNFPVHGL (1083.53 Da) and FKVGQENTPILK (1372.77 Da) were identified utilizing nano-UHPLC-MS/MS as well as their de novo spatial structures and interaction with ferrous ion were simulated by PEP-FOLD 3. As a whole, the proteolysate/peptides could be filled as an iron chelator which could shield human body from iron deficient-related disorders or as a functional proteolysate preparation to upgrade food properties.

BACKGROUND: Despite promising advances in stem cell-based therapy, the treatment of ischemic cardiovascular diseases remains a big challenge due to both the insufficient in vivo viability of transplanted cells and poor angiogenic potential of stem cells. The goal of this study was to develop therapeutic human cardiac progenitor cells (hCPCs) for ischemic cardiovascular diseases with a novel M13 peptide carrier. METHOD: In this study, an engineered M13 peptide carrier was successfully generated using a QuikChange Kit. The cellular function of M13 peptide carrier-treated hCPCs was assessed using a tube formation assay and scratch wound healing assay. The in vivo engraftment and cell survival bioactivities of transplanted cells were demonstrated by immunohistochemistry after hCPC transplantation into a myocardial infarction animal model. RESULTS: The engineered M13(RGD+SDKP) peptide carrier, which expressed RGD peptide on PIII site and SDKP peptide on PVIII site, did not affect morphologic change and proliferation ability in hCPCs. In contrast, hCPCs treated with M13(RGD+SDKP) showed enhanced angiogenic capacity, including tube formation and migration capacity. Moreover, transplanted hCPCs with M13(RGD+SDKP) were engrafted into the ischemic region and promoted in vivo cell survival. CONCLUSION: Our present data provides a promising protocol for CPC-based cell therapy via short-term cell priming of hCPCs with engineered M13(RGD+SDKP) before cell transplantation for treatment of cardiovascular disease. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13770-020-00244-w) contains supplementary material, which is available to authorized users.

A liquid chromatography tandem mass spectrometry method using positiveelectrospray ionization source (ESI+), multiple reaction monitoring (MRM) mode has been developed and validated to simultaneously determine 16 illegaldyes in different food groups. The method was based on the extraction of analytes from samples using QuEChERS technique. After being cleaned up d-SPE tube with mixture of MgSO4, PSA and C18 sorbent, the extract was analyzed by LC-MS/MS. Each illegaldyewas characterized by a precursor ion and two product ions. The method allows the screening of the simultaneous presence of 16 illegal substances at the lowest concentration of 5µg/kg forrhodamin B, crystal violet, chrysoidine G, auramine O, sudan black B, pararosanilin and of 50µg/kg for remaining substances. The specificity of the methodmet 657/2002/EC requirements. The methodwas linear in the range from 1-1000µg/L and themethod detection limit was from 5-50 µg/kg, the recovery ranged from 73-104% and the relative standard deviations were lower than 16.4%. The method has been applied to analyze 30 samples of dried beef, dry chicken, chutney, chili powder and food coloring samples. Rhodamine B, sudan I and auramine O were detected in two chili powder and 04 food coloring samples.

This study reported a single-step method for the fabrication of magnetic cellulose nanocrystals (MGCNCs) by coprecipitation iron oxide nanoparticle onto cellulose nanocrystals (CNCs). Cellulose nanocrystals (CNCs) were derived by hydrochloric acid hydrolysis (HCl 6 M, 25 mL/g cellulose) in the optimum condition at 90 °C for 90 min. Pure cellulose was isolated from Nypa fruticans branches, a popular tree in Vietnam. The structure and morphology of CNCs were characterized by crystallinity index, morphology and thermal stability. TEM images showed that the average fiber length of the nanocrystals was 410 nm with a diameter of 10 nm (aspect ratio of 41) and the crystallinity index of 85.2 % (by XRD). The as-prepared MGCNCs were characterized by Fourier transform infrared spectroscopy (FTIR), wide-angle X-ray diffraction measurement (XRD), thermal gravity analysis (TGA) and vibrating sample magnetometry (VSM). The results showed that the magnetic cellulose nanocrystals absorbed about 51 % w/w on CNCs surfaces with magnetic properties and the saturation magnetization of about 24 emu/g. Possessing the biocompatibility as well as paramagnetism, the magnetic cellulose nanocrystals were promising materials for environmental treatment.

lbgBackground and Objective:l/bg ligTrametes versicolorl/ig has not only been valued in medical use but also in environmental protection. One of the major challenges currently faced in the commercial cultivation of ligT. versicolorl/ig is finding superior strains that can produce high yields. In an attempt to search for high-yield potential ligT. versicolorl/ig, two wild strains, namely VNUA and BV, were isolated and evaluated for potential cultivation. lbgMaterials and Methods:l/bg Optimized culture conditions were set up by one-individual factor-at-a-time. Four different kinds of culture media, including Czapek, Raper, PGA and modified Potato Dextrose Agar (PDA), were investigated to ascertain the optimal media. The efficiency of sawdust and rice grain for mother spawn production was evaluated. Different combinations of sawdust and rice husk were tested to investigate the most favorable substrate mixtures. lbgResults:l/bg The ideal medium and temperature for the favorable mycelial growth of ligT. versicolorl/ig were PGA and 30°C, respectively. The optimal spawning material for upscaling of the mycelium was Treatment D (20% rice grain, 79% sawdust and 1% calcium carbonate). The strains were successfully cultivated in a basal substrate combination of sawdust and rice husk supplemented with wheat bran. Investigated strains responded differently to different substrates cultivation. Of note, compared with strain BV, strain VNUA showed a significantly higher biological efficiency (7.3%). lbgConclusion:l/bg Wild ligT. versicolorl/ig strains were successfully fructified under artificial cultivation conditions. Strain VNUA can be considered as a potential strain for commercial cultivation. The use of sawdust for the spawn production of ligT. versicolorl/ig can reduce the cost of manufacturing.

TiO2 has gained tremendous attention as a cutting-edge material for application in photocatalysis. The performance of TiO2 as a photocatalyst depends on various parameters including morphology, surface area, and crystallinity. Although TiO2 has shown good catalytic activity in various catalysis systems, the performance of TiO2 as a photocatalyst is generally limited due to its low conductivity and a wide optical bandgap. Numerous different studies have been devoted to overcome these problems, showing significant improvement in photocatalytic performance. In this study, we summarize the recent progress in the utilization of TiO2 for the photocatalytic hydrogen evolution reaction (HER). Strategies for modulating the properties toward the high photocatalytic activity of TiO2 for HER including structural engineering, compositional engineering, and doping are highlighted and discussed. The advantages and limitations of each modification approach are reviewed. Finally, the remaining obstacles and perspective for the development of TiO2 as photocatalysts toward high efficient HER in the near future are also provided. Keywords: TiO2, 2D materials, Composites, Doping, Photocatalysis, HER