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Bacterial secondary metabolites have an important role in encouraging the growth of plants by influencing phytohormone production and metabolism. The effect of secondary metabolites secreted by an actinobacterium Zhihengliuella sp. ISTPL4 (Z. sp. ISTPL4) on growth promotion in the Oryza sativa plant was studied. The growth of Z. sp. ISTPL4 has been evaluated in the presence of Arsenic (As) up to the concentration range of 0.2–1.9 mM followed by observing the growth of rice in the presence of As. The present study was carried out to analyze the significant role of metabolites released by Z. sp. ISTPL4 in growth-promoting activities of plants. We have also reported various metabolites released by Oryza sativa after microbial inoculation under normal growth conditions and in the presence of As stress. It was observed that 43 metabolites were released by Z. sp. ISTPL4 under normal conditions and 34 metabolites were released in the presence of As stress. Some of these metabolites including Hexadecane, Heptadecane, Hexadecanoic acid methyl ester, Eicosane, Cyclo (L-prolyl-L-valine) were common among metabolites released by Z. sp. ISTPL4 in the presence of normal growth conditions and under As stress. The area percentage of hexadecenoic acid methyl ester, methyl stearate, octadecanoic acid, 2,3-dihydroxypropyl ester was higher in the presence of As stress than its concentration under normal growth conditions while hexadecane is released in the presence of As stress only. These metabolites are involved in antimicrobial, antiproliferative antioxidants and plant growth promotion by stimulating gibberellin synthesis. The results of our research indicate that under different biotic and abiotic stress conditions, the actinobacterium Z. sp. ISTPL4 can be deployed to improve sustainable agricultural practices. [Display omitted] • Zhihengliuella sp. ISTPL4 tolerate up to 2 mM concentration of arsenate. • Secondary metabolite production in Zhihengliuella sp. ISTPL4. • Abiotic stress-mediated secondary metabolite production in rice. [ABSTRACT FROM AUTHOR]

[Display omitted] • Torrefaction treatment improves the fuel characteristics of lignocellulose. • Temperature is a regulating factor for torrefied product's properties. • Lignocellulosic biomass produces solids, liquids, and gas products during torrefaction. • Bio-coal has potential applications in energy, environment, agri-food, and polymer composite. Leveraging biofuel derived from biomass stands as a pivotal strategy in reducing CO 2 emissions and mitigating the greenhouse effect. Biomass serves as a clean, renewable energy source, offering inherent benefits. However, despite its advantages, biomass encounters obstacles hindering its widespread industrial applications, including its relatively low calorific value, limited grindability, high water content, and susceptibility to corrosion. The torrefaction process has garnered significant attention as an effective method for enhancing the quality of raw biomass for energy production. In this review, we briefly discussed the mechanism of bio-coal preparation using biomass, physico-chemical characterization of different torrefied feedstocks, and the effect of torrefaction parameters, along with the effect of the different types of reactors on biomass torrefaction. Furthermore, bio-coal's emission characteristics and fuel quality throughout the thermal treatment have been covered. Thus, bio-coal finds a wide range of applications in sustainable energy generation, environmental remediation, agri-food development, polymer composites, and others. [ABSTRACT FROM AUTHOR]

Glycerol contains 52 wt% oxygen content, therefore unable to be directly used as fuel due to its poor combustion ability. Thus, the catalytic conversion of glycerol into various oxygen-containing fuel additives is grabbing more attention nowadays. This work provides a novel, sustainable, and eco-friendly method for synthesizing heterogeneous acid carbon catalysts from pearl millet cob (PMC) waste. The hydrothermal carbonization process was carried out at different temperatures to fabricate the series of sulfonated pearl millet cob (SPMC) catalysts. XRD, FT-IR, SEM-EDS, XPS, BET, TGA, and CHNSO analyses were performed to characterize fabricated catalysts. The synthesized catalyst, SPMC-70 (catalyst synthesized at 70 °C temperature), possesses OH, COOH, and SO 3 H functional groups and a significant total acid density (2.03 mmol/g) with 37 m2/g surface area. The SPMC catalysts were employed for the microwave-assisted acetalization reaction of glycerol with acetone for solketal production. The optimization process was carried out using various reaction parameters, including catalyst dosage (2–6 wt.%), reaction temperature (30–60 °C), glycerol to acetone (GL to AC) molar ratio (1:3–1:9), and reaction time (4–13 min). The SPMC-70 catalyst showed the highest catalytic activity among all the synthesized catalysts and provided 99.11 ± 0.3 % GL conversion with 100 % selectivity of solketal under optimal reaction conditions. Additionally, the recyclability test was performed, and it found that the best catalyst was reusable for up to five reaction cycles. These results showed the effectiveness of carbon-based heterogeneous acid catalysts in deriving a fuel additive, solketal. [Display omitted] [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ejor.2007.07.021 Byline: Malay Bhattacharyya, Abhishek Chaudhary, Gaurav Yadav Keywords: Conditional VaR; GARCH; Pearson's type IV distribution; Risk management Abstract: This paper presents a new value at risk (VaR) estimation model for equity returns time series and tests it extensively on Stock Indices of 14 countries. Two most important stylized facts of such series are volatility clustering, and non-normality as a result of fat tails of the return distribution. While volatility clustering has been extensively studied using the GARCH model and its various extensions, the phenomenon of non-normality has not been comprehensively explored, at least in the context of VaR estimation. A combination of extreme value theory (EVT) and GARCH has been explored to analyze financial data showing non-normal behavior. This paper proposes a combination of the Pearson's Type IV distribution and the GARCH (1,1) approach to furnish a new method with superior predictive abilities. The approach is back tested for the entire sample as well as for a holdout sample using rolling windows. Author Affiliation: Indian Institute of Management Bangalore, Bannerghatta Road, Bangalore 560076, India Article History: Received 20 September 2006; Accepted 12 July 2007 Article Note: (footnote) [star] This work was carried out when Abhishek and Gaurav were Graduate Students at the Indian Institute of Management Bangalore. Abhishek is currently working as Practice Manager-Structured Finance at Ocwen Financial Solutions Private Limited, Bangalore, and Gaurav as Management Associate at the Development Bank of Singapore.

Growing biodiesel production creates a significant volume of glycerol (Gly), a by-product that must be transformed into valuable compounds by developing novel and sustainable technologies. Solketal is one of several valuable compounds derived from residual Gly released during biodiesel synthesis. A green synthetic process followed by the co-precipitation method was used to fabricate NiS@Functionalized Biochar (NBS) using Azadrichta indica leaf extract. The nanocatalyst was extremely active for microwave-assisted solketal synthesis from Gly and acetone. A 99.7 ± 0.3 % conversion of Gly with 100 % solketal selectivity occurred under the optimum reaction conditions (catalyst loading 4 wt%, Gly to acetone molar ratio 1: 5, reaction time 6 min, and temperature 65 °C). The suggested reaction mechanism demonstrates the selective synthesis of solketal. The NBS catalyst showed excellent reusability up to six cycles, and after that, it was used for the photodegradation of tinidazole, where 89.14 % degradation efficiency was obtained within 110 min of sunlight irradiation. A narrow energy band gap (1.99 eV) and effective charge separation favor the photocatalytic activity of the reused catalyst. The environmental friendliness of the catalyst for the solketal synthesis process was examined by studying green metrics. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel MOF encapsulated by Fe(III)-substituted H 3 PW 12 O 40 was developed. • Sustainable microwave-assisted biodiesel production in a short duration of 40 min. • FPW-HK catalyst significantly reduced energy consumption and time with E a = 27.24 kJ/mol. • Possible mechanism of biodiesel production on the catalyst surface was proposed. • Life-cycle cost analysis estimated the cost of 1 kg of biodiesel to be $0.6. In the present research, an attempt has been made to design a highly efficient Metal-Organic Framework encapsulated by Fe (III)-substituted keggin H 3 PW 12 O 40 nanocomposite for the production of biodiesel via microwave-assisted esterification reaction within a very short duration of 40 min. This phenomenon can be attributed to the enhanced mass transfer between the surface of the catalyst and the reactants, leading to a reduction in reaction time and energy consumption. Notably, the FPW-HK catalyst significantly lowers the activation energy to 27.24 kJ/mol, achieving an outstanding biodiesel yield of 99.14 ± 0.4 % at optimum reaction conditions, with a pseudo-first order rate constant of 0.08954 min−1. This signifies that the reaction catalyzed by the fabricated FPW-HK catalyst is highly energy efficient. Moreover, from the perspective of time and cost-effectiveness, the fabricated catalyst has the potential to reduce the overall cost of the biodiesel production, as validated by life-cycle cost analysis (LCCA). 1HNMR, 13CNMR, and GC–MS analysis were performed to quantify the composition of the produced biodiesel. Onward, the investigation of the influence of various process factors such as OA, methanol molar ratio, catalyst loading, reaction time, and temperature was performed to optimize the esterification reaction. Furthermore, a possible reaction mechanism over the surface of the synthesized FPW-HK nanocatalyst was suggested to discuss the production of biodiesel. The catalyst displayed good reusability up to six cycles besides demonstrating potential for industrial applications. The LCCA estimated the price of 1 kg of biodiesel to be merely $0.593, suitable for commercialization. Moreover, it exhibits potential for the esterification of low-cost feedstocks with high content of free fatty acids (FFA), thus displaying immense utility for industrial applications. The results suggest that the combination of MOF-supported keggin heteropolyacids and microwave irradiation can be a promising alternative to biodiesel production with reduced time and energy consumption, besides holding a significant promise for large-scale green biodiesel production for commercialization. [ABSTRACT FROM AUTHOR]

This comprehensive review article navigates the complex landscape of environmental phenol pollution, extensively analyzing its occurrence, toxicity, and advanced treatment options. The authors begin by describing the many sources of phenol, which range from industrial effluents to home wastewater, to provide a complete knowledge of its pervasive presence in environmental matrices. The paper emphasizes the environmental and human health ramifications of phenol, establishing the framework for a sophisticated understanding of the enormity of the situation. The review focuses on phenol removal, with the authors categorizing approaches into conventional, biological, and advanced removal technologies. The time-tested and dependable traditional procedures are contrasted with the dynamic landscape of biologically mediated treatments, providing readers with insights into the emerging paradigm of phenol elimination. The review's distinguishing characteristic is its in-depth examination of advanced removal technologies, which include nanofiltration, photoreduction, AOP-assisted degradation, adsorption, and synergetic approaches. A thorough comparison study, supplemented by a realistic cost evaluation, gives a complete picture of each method's efficacy and economic viability. Beyond a retrospective examination, the study identifies potential options and problems in phenol elimination. This forward-thinking viewpoint presents the study as a valuable resource for scholars and policymakers navigating the path to sustainable environmental policies. This review article stands out as a light of knowledge in a literary landscape filled with works of different depths, providing a thorough roadmap for successful phenol mitigation techniques and contributing to the collaborative struggle for a cleaner and more sustainable environmental future. [Display omitted] • Source, transportation, and toxicity of phenolic compounds have been analyzed. • Conventional and biological phenol removal methods have been summarized. • Advanced removal techniques such as photocatalysis and adsorption have been discussed. • Cost analysis of the removal techniques has been carried out. • Future outlooks and challenges have been debated. [ABSTRACT FROM AUTHOR]

This study reports the successful synthesis of an acid-functionalized ZnS/Biochar (ZBC-SO 3 H) nanocatalyst through a co-precipitation method utilizing Camellia sinensis leaf extract. The ZBC-SO 3 H nanocatalyst was employed for the microwave-assisted acetalization reaction of glycerol with acetone for selective solketal synthesis (biofuel derivative). Through systematic optimization of multiple reaction parameters, the most favorable conditions for solketal synthesis were identified. The ideal reaction conditions involved an 8:1 M ratio of acetone to glycerol (AC to GL), a 6 wt% catalyst loading, an 8-min reaction time, and a temperature of 60 °C. A significantly high surface area of 326.21 m2/g for the ZBC-SO 3 H nanocatalyst demonstrates its exceptional potential for catalytic applications. In addition, the plausible reaction pathway for selective solketal synthesis was suggested. The catalyst was reusable up to 6 reaction runs in the solketal synthesis, which remarks the high stability of the ZBC-SO 3 H. Further, the reusability of the ZBC-SO 3 H (remaining catalyst after 6 runs) was examined in the adsorption of methylene blue (MB) dye. This groundbreaking study showcases the exceptional performance of the ZBC-SO 3 H nanocatalyst in selective solketal production and its remarkable reusability in the adsorption of methylene blue dye. The outstanding results underscore the novelty and significance of this research endeavor. [Display omitted] [ABSTRACT FROM AUTHOR]

The dual bamboo and coconut waste-derived catalyst was utilized to enhance the esterification reaction between two incompressible reactants, (oleic acid and methanol), to increase the mass transfer, which further decreased the reaction time and energy. The comparison study of the sulfonated dual waste biochar (DWBS) with single biomass-derived catalysts, sulfonated bamboo biochar (BBS), and sulfonated coconut husk biochar (CHBS) shows that the DWBS catalyst efficiently produces biodiesel by esterification reaction under optimum conditions. The catalyst significantly reduces activation energy to a greater extent, with a value of 32.32 kJ/mol as compared to BBS and CHBS catalysts. The reusability study reveals that the DWBS catalyst is effective for up to six cycles, demonstrating the catalyst's remarkable stability. The results indicate that the DWBS catalyst could be used for biodiesel production with low catalyst loading and a high reaction rate. [Display omitted] [ABSTRACT FROM AUTHOR]

• This review highlights the recent advancement in the waste-derived materials. • Various characteristics and synthesis methods for novel materials are given in this review. • Waste-derived materials are cost-effective, efficient and environment-friendly. • The current development problems and future perspectives of waste-derived materials are pointed out. Human faces major problems regarding the environment. Although many materials are used to solve these problems, they are not so effective against them because they generate secondary pollution. Waste materials such as fly ash, biomass, red mud, and others material are used in various processes for effectively removing them. Also, the utilization of waste materials into valuable derivatives results in these materials' cost efficiency. Additionally, waste materials have several advanced properties like high surface area, high functional group, high adsorption capacity, etc. The efficiency of waste materials increases by incorporating nanoparticles, which are used for multifunctional applications. Nanoparticles may be stabilized and dispersed with the help of waste materials. In this review, (1) recent development in the waste-derived materials is discussed, (2) the properties and synthesis of waste materials are discussed, and (3) various process like adsorption, photodegradation, and advanced oxidation process (AOP) for environmental remediation are discussed. In conclusion, we have also provided future directions for the development of novel waste-based composite materials for efficient dealing with these kinds of problems. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • ZIS based photocatalyst effective solve the environment problems and deals with the energy crisis. • Numerous synthesis methods are used to develop different morphologic ZIS-based catalyst. • Modification technique increase the catalyst efficiency by harvesting visible light. • This review demonstrated the recent advancement in the field of ZIS-based catalyst. • This review includes the mechanism of H 2 generation. Photocatalysis has shown tremendous potential to solve world problems with environmental pollution and energy scarcity. In this list, ternary metal chalcogenides ZnIn 2 S 4 (ZIS) has garnered attention over others due to its superior visible light capability, low-cost, excellent chemical stability, and substantial interdisciplinary interest. Recent investigations have shown the development of a wide range of ZIS nanocomposite structures. Several modulated strategies are involved in enhancing the activity of ZIS-based nanocomposites. In this review, various synthesis strategies of ZIS are added. Furthermore, we observed the advantage of the ZIS electronic structure for water splitting along with pollutants removal, organic synthesis, sensing, nitrogen fixation, and many more. Modification leads to enhanced material effectiveness for hydrogen production. This review hopes to inspire further research into this promising material for application in efficient energy and environment by showcasing the state-of-the-art of ZIS photocatalysts. In this context, we discussed the mechanism behind hydrogen production. [ABSTRACT FROM AUTHOR]

• Agricultural waste of rice husk was used as a precursor for producing sulfonated catalyst. • A solid acid catalyst was developed by a simple modification by H 3 PO 4 to increase porosity. • 99.8% of FAME production was obtained under optimized process without glycerol. • As compared to other sulfonated catalysts, the conversion of FAME is excellent. • The fabricated catalyst shows excellent reusability up to seven cycles. The present study aims to confirm the feasibility of O. sativa husk for the fabrication of high-performing heterogeneous-based carbon catalysts. A series of catalysts are fabricated by a facile carbonization method followed by sulfonation. The heterogeneous catalysts derived from agricultural wastes were used in the esterification process to synthesize fatty acid methyl ester (FAME). The sulfuric acid concentration was varied from 2 to 10 mM L–1 to study its influence on the FAME yield. The carbonized O. sativa husk treated using 10 mM L–1 of H 2 SO 4 shows high acid density (2.26 mmol/g) and S-content (5.31%). Under various optimized processes, the FAME yield reached a maximum of 99.6 ± 0.2% {60 min at 80 °C, 8 wt.% catalyst dosage, and a 24:1 molar ratio of methanol to oleic acid (OA)}. The conversion of oleic acid into methyl oleate also depends on the carbon chain length of alcohol. It was found that as the carbon chain length increases, the FAME yield decrease. The solid acid catalyst shows an excellent FAME yield of 99.6 ± 0.2% and an activation energy of 76.11 kJ mol–1, whereas the value of pre-exponential factor A is 1.4 × 1010 min−1. The as-synthesized catalyst is reusable for up to seven cycles because of its high total acid density and S-content. An ecologically friendly and promising strategy for green fuel generation shown in this work by using a solid renewable acid catalyst generated from agricultural waste. [Display omitted] [ABSTRACT FROM AUTHOR]

Nowadays, organic pollutants create severe problems worldwide. Phenolic compounds are the harmful pollutants that are developed from industrial effluents, thus causing several environmental problems. Low-cost materials show good potential capabilities for removal of phenolic compounds but are not so effective, so modification is required. New generation nanocatalysts are thought to be excellent for phenol removal. Removal of phenolic pollutants by photodegradation may lead to the decrement of these problematic groups. In this review, (i) a new generation of catalysts for the removal of phenolic compounds is discussed, (ii) nanocatalysts for photodegradation processes, and (iii) the mechanisms involved in photodegradation processes are also discussed. It is noticeable from the analysis that new generation catalysts for photodegradation processes have been demonstrated for high removal abilities of irrefutable phenolic compounds. Finally, future perspectives are also given in this article for the further development of next-generation catalysts. [Display omitted] • This review highlights the recent photocatalytic progress in the degradation of phenolic compounds. • Various nanocomposites like metal oxides; metal sulfides are discussed in this article. • The low-cost materials like biochar and other carbon-based nanocomposite are also discussed. • In recent years, MXene is found to be efficient photocatalyst for environmental remediation. • Future prospectus and challenges are discussed in this article. [ABSTRACT FROM AUTHOR]

• Recent photocatalytic progress of the mixed anion materials was discussed. • Mechanochemical doping and hydrothermal/solvothermal process were described. • Mixed anions materials solve environmental remediation and energy related problem. • Use of mixed anions for pollutants removal, CO 2 reduction and water splitting. Rapid growing energy demands owing to the reduction of fossil fuels as well as environmental pollution call for renewable, environment-friendly energy sources. Photocatalysis has widely applied for water splitting to generate H 2 , oxygen evolution, organic synthesis, pollutants degradation, and much more. Today, various multi-anion materials are used, which are synthesized via easy and environment-friendly methods. The multi-anion materials mainly consist of N/C/O, S/O, N/F/O, and N/O, which shows excellent photocatalytic activity. Also, multi-anion contains metal cations and two anionic species. Multi-anion photocatalysts have vast absorption bands and visible-light absorption efficiency. This review discusses the basic information of multi-anion compounds like synthesis, physical and chemical properties. Meanwhile, some research progress of multi anion materials was also given for CO 2 reduction, water splitting, and pollutants removal. [Display omitted] [ABSTRACT FROM AUTHOR]

Photocatalytic water splitting using solar energy offers a sustainable pathway for green hydrogen production. Metal sulfides, such as ZnS, SnS₂, CdS, MoS₂, CuS, ZnIn 2 S 4 , CdIn 2 S 4 , and others, have garnered significant attention due to their tunable morphology, band structures, visible light sensitivity, and optical properties. This review explored the advancements in metal sulfide-based photocatalysts, focusing on their synthesis, structural classification, and bandgap engineering for enhanced hydrogen production. Key characterization techniques, including XRD, SEM, TEM, UV-DRS, XPS, and others were discussed for understanding their structural and optical behavior. The review emphasizes recent innovations, challenges, and future directions in optimizing these materials for efficient solar-driven H₂ generation, providing insights for researchers and policymakers in clean energy development. • Photocatalytic H 2 production is a promising strategy for sustainable energy future. • Basic concepts, efficiency, and mechanism of hydrogen production are highlighted. • Metal sulfides and their composites used in H 2 generation are mentioned. • Detailed characterization methods of metal sulfide-based photocatalysts discussed. • Metal sulfides are overcoming challenges and paving the way for future advancements. [ABSTRACT FROM AUTHOR]

A wide variety of dental ceramic composites have been introduced in the restorative dentistry in order to associate the desired aesthetics and superior mechanical performance. Mechanochemically derived leucite based bioactive glass ceramic composites have been prepared and studied by their thermal, crystal structure, microstructural, mechanical and biological behavior. In the prepared glass-ceramic composites, fine alumina has been added to improve their mechanical properties because it has biocompatibility, high hardness and good mechanical strength. Flexural strength and coefficient of thermal expansion (CTE) have been studied and the results are compared to the commercial dentine. Alumina added glass ceramic composites show high flexural strength than that of the pure leucite based glass ceramic composite. A second phase nepheline has been formed in the alumina added samples. Nepheline has high CTE. This causes a slight increase in the CTE of the whole matrix. Micrographs show the complete attachment and proliferation of the SSC-25 cells on the surface of the samples. This confirms the bioactive behavior of the prepared composites. Therefore, it is concluded that the addition of alumina to the glass ceramic composite is a successful approach to improve its mechanical and biological properties. [ABSTRACT FROM AUTHOR]