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Dye released by industrial is one of the main known pollutants in wastewater, which is harmfully affected to the human health. Adsorptive method by absorbents and photocatalytic degradation technique are advanced technologies to remove dyes from wastewater. However, the single technique mentioned above has imperfections limiting its application. Herein, in order to integrate the two techniques and take both advantages, bacterial cellulose (BC) based titanium dioxide (TiO 2 )‑cadmium sulfide (CdS) nanocomposite gel was prepared by microwave-assisted solvothermal synthesis. The BC@TiO 2 -CdS nanocomposite gel was characterized by SEM, EDS, XRD, XPS, Raman spectral and TG, its photocatalytic mechanism was proved by PL. The results showed the TiO 2 -CdS nanophotocatalyst exhibited binary hierarchical structure and followed the Z-scheme type photocatalytic system. The Z-scheme heterojunction is advantageous for photo-generated charge separation and migration. The photocatalytic performance of BC@TiO 2 -CdS nanocomposite gel was evaluated by MB degradation under visible light irradiation. Due to synergistic effect of BC matrix and TiO 2 -CdS, the as-prepared BC@TiO 2 -CdS nanocomposite gel possesses enhanced photocatalytic activity with 94.47 % removal of methylene blue (MB) after 180 min visible light irradiation. Therefore, this work provides a facile route to fabricate bio-mass based efficient nanophotocatalytic material for pretreating the water pollution., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

In this study, we report a smart and green strategy to synthesize copper sulfide nanoparticles (CuS-NPs) for clinically translatable cancer treatment. For the first time, the preparation of CuS-NPs was developed by taking advantage of the copper-amine complex as the copper source and sodium sulfide as the sulfide source, in which the quaternized chitosan (QCS) was used as a biotemplate and stabilizing agent. The obtained QCS/CuS-NPs composites (CuS@QCS-NPs) were spherical and stable with an average diameter of 5.6 nm, and showed strong NIR absorbance for photothermal conversion. Moreover, in vitro and in vivo cancer theranostic capability of CuS@QCS-NPs without any biomodification was evaluated. The result reveals that after intratumoral (i.t.) injection of CuS@QCS-NPs with NIR laser irradiation (808 nm, 1.5 W/cm 2 , 5 min), the 4T1 mammary tumor growth could be effectively suppressed comparing with the other control groups, and there was no obvious lethal toxicity to liver function, kidney function, and vital organs. Such QCS-stabilized CuS-NPs may provide an alternative for clinical application of CuS-based photothermal therapy., (Copyright © 2018. Published by Elsevier B.V.)

Rice straw is one of the most abundant agricultural residues in China. It is considered as a promising raw material for bioethanol production. In this work, rice straw was pretreated by sodium sulfite-formaldehyde (SF) for improving enzymatic saccharification. The SF pretreatment, using proven technology and industrialized equipment, showed efficient delignification selectivity and high carbohydrates retention in pretreated solid. The highest sugar yields of 79.0%, 88.8% and 71.1% for total sugar, glucan and xylan, respectively were obtained at an enzyme loading of 40 FPU/g-substrate after the raw material pretreated with 12% sodium sulfite at 160°C. About 75% of lignin was dissolved in pretreatment spent liquor and 78% of silica was retained in the residue of enzymatic hydrolysis. The results proved sulfite-formaldehyde as a promising pretreatment for the production of bioethanol as well as potential high value added by-products of silica nanoparticles and lignosulfonate., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Green liquor consists of sodium carbonate and sodium sulfide and is readily available in any kraft mills. The green liquor pretreatment process for bioethanol production was developed for wood chips. This process uses only proven technology and equipment currently used in a kraft pulp mill and has several additional advantages such as high sugar recovery and concentration, no inhibitive substances produced, as compared to acid-based pretreatment methods. The liquor was used to pretreat corn stover for enhancing enzymatic hydrolysis in bioethanol production. Pulp yield of 70% with 45% lignin removal was achieved under optimized conditions (8% total titratable alkali, 40% sulfidity and 140°C). About 70% of the original polysaccharides were converted into fermentable sugars, using 20 FPU/g-pulp of enzyme in the subsequent enzymatic hydrolysis. The result indicates that green liquor is a feasible pretreatment to improve the enzymatic saccharification of corn stover for bioethanol production., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A fast and sensitive method based on fluorescent carboxymethyl chitosan/CdS quantum dots (CMCS-CdS QDs) composites was developed for specific detection of Staphylococcus aureus in food and the environment. Fluorescent CMCS-CdS QDs were prepared in aqueous solution through a green method. A human immunoglobulin (IgG) antibody was then bioconjugated to the QDs in the presence of 1-ethyl-3-(3)-dimethylaminopropyl carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) to make a novel type of mono-dispersed water-soluble fluorescent bioprobes. The fluorescent bioprobes were employed to identify S. aureus by incubating them with the bacteria for a certain time and observing the marked cells under fluorescence microscopy after removing free fluorescent QDs. Fluorescence microscopy images showed the S. aureus cells were successfully recognized by the bioprobes. Several other bacteria commonly found in environment such as Escherichia coli and Bacillus subtilis were also incubated with the bioprobes to test their specificity. It was found that the novel QDs-CMCS-IgG bioprobes had specific identification to S. aureus cells. Fluorescence measurement using a luminescence spectrometer could be applied to quantify S. aureus cells. The fluorescence intensity of the samples at 600 nm was proportional to the cell concentration in the range of 10(3)-10(7) cfu/ml, and the detection limit was as low as 900 cfu/ml. Considering the simplicity and cost-efficiency of this method, its application in the identification and quantification of bacteria in clinical, food and environmental samples is anticipated., (© Koninklijke Brill NV, Leiden, 2011)

Air emissions from the pulp and paper industry frequently contain reduced sulfur compounds (RSC), such as dimethyl sulfide (DMS) mixed with volatile organic compounds (VOC) (e.g., methanol, MeOH) and it is desirable to treat either one or both of these groups of compounds. The objective of this study was to assess the effects of VOC (MeOH) on the biofiltration of DMS. Results obtained from continuous experiments using three bench-scale biofilters packed with inorganic material clearly show that MeOH has a positive effect (11-fold increase) on the biofiltration of DMS. Further experiments indicate that MeOH addition enhances biomass concentration and viability (threefold) in the biofilters. However, a suspension of MeOH addition causes a rapid significant increase (twofold) in the removal rate of DMS, suggesting that the presence of MeOH also has a competitive effect on DMS biodegradation. This negative effect was also confirmed in batch experiments. The decrease of biofilter performance with time for a long-term suspension of MeOH addition indicates that MeOH addition is necessary to sustain a high removal rate of DMS in inorganic biofilters. Results on metabolic products of DMS biodegradation demonstrate that DMS is almost completely converted to sulfate in the absence of MeOH, while it is partially oxidized to elemental sulfur in the presence of MeOH. This study suggests that there exists an optimum mix of DMS and MeOH for the treatment of DMS emissions in inorganic biofilters., ((c) 2006 Wiley Periodicals, Inc.)