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The relevant information on the impacts of emerging organic contaminants (EOCs) on the ecological environment, especially on the group of more vulnerable activated sludge is relatively less. In order to track biological activity of the aerobic sludge which is the most extended biological stage in the process of waste water treatment, the effects of bisphenol A (BPA) and pentachlorophenol (PCP) on urease, invertase and dehydrogenase were analyzed by spectrophotometry. It was found that the effects of BPA on urease and invertase mainly showed activation. The maximum relative impact rate on urease and invertase reached +91.7% and +182.3% respectively. The influence of BPA on dehydrogenase was observed to show visible inhibition. The maximum relative impact rate of BPA on dehydrogenase reached −89.9%. Effect of PCP on 3 kinds of enzyme were included activation (+) and inhibition (−) with different periods and concentration of exposure experiments. The maximum of the relative impact rates were +41.2% and −19.6% for urease, +84% and −76.8% for invertase, +18.0% and −54.8% for dehydrogenase respectively. Based on evaluating the sensitivity of physiological and biochemical indicators, and the accuracy of analytical methods as well, invertase activity could be recommended as a sensitive index for characterization of activated sludge. The obtained results could be used to analyze the potential impact of EOCs on ecological environment and even social and economic activities with significant information collected. It is helpful to serve as the basis for implementing relevant environmental regulatory and making decision, and for the relating enterprises to cope with adverse changes induced by community function under stress instantly.

Zn2SnO4 quantum dots (QDs) decorated Bi2WO6 nanocomposites were prepared via a two-step hydrothermal reaction progress. The Zn2SnO4 QDs were highly dispersed onto the surface of plate-shaped n-type Bi2WO6, which allows more photons to be harvested and effectively improve the separation and utilization efficiencies of photoinduced electrons and holes due to the formation of heterojunction. Among them, 3% Zn2SnO4 QDs/Bi2WO6 nanocomposite showed the highest photocatalytic performance (95.5% of acetone degradation), compared with other different amounts of Zn2SnO4 QDs, which are 5.86 and 1.99 times higher than those of pure Bi2WO6, respectively. Meanwhile, the hybridized sample was investigated by four successive photocatalytic degradation of acetone under visible light, displaying great photo-stability. Furthermore, through in-situ FTIR, acetaldehyde, acetic acid and formaldehyde were certified as intermedias during the photocatalytic degradation of acetone. Based on these results, the relationship between photocatalytic activity and the formation of Zn2SnO4 QDs/Bi2WO6 heterojunction is further discussed and the possible reaction mechanism is proposed. Such novel photocatalyst as visible light responsive catalyst provides a new choice for the efficient degradation of contaminants.

The environmental residues of active pharmaceutical ingredients (APIs) are associated with environmental risks and health problems, the influence to environment have become a matter of public concern. In this paper, the individual and joint toxicities to vibrio fischeri of three APIs, including ibuprofen, azithromycin, and triclosan were investigated. The EC50 endpoint values of the above tested APIs were 36.5 × 10−5 mol L−1, 30.26 × 10−5 mol L−1, and 0.0155 × 10−5 mol L−1 respectively. It was indicated that the endpoint toxicities to vibrio fischeri for different mixtures are higher than those of the individual toxins. The joint toxicities of the multiple systems of three pharmaceuticals were evaluated by the additive index, toxicity unit, and mixed toxicity index methods. The consistent evaluation results were obtained. It was observed that antagonistic effects in binary and ternary systems were appeared different antagonistic strengths. It was deduced that different functional groups of the studied pharmaceuticals could affect the physiological and biochemical reaction processes of organisms. The obtained data of the acute toxicities of pharmaceuticals to vibrio fischeri can facilitate the evaluation of the environmental risks associated with emerging pollutants. Keywords: Ibuprofen, Azithromycin, Triclosan, Joint toxic effects

Herein, uniform AgX/Ag2CrO4 (X = Cl, Br, I) NR hybrids were successfully prepared by a facile in-situ anion exchange reaction at room temperature. When AgX was formed on the surface of Ag2CrO4 NRs, the light absorption range AgX/Ag2CrO4 hybrids show apparent red shifting by compared with the pure Ag2CrO4 NRs, which indicates the enhanced ability of utilizing solar energy. Moreover, the as-prepared AgBr/Ag2CrO4 NR hybrids exhibit the highest photocatalytic activity for degradation of phenol under visible light irradiation owing to more suitable band offset between AgBr and Ag2CrO4 to form type-II heterojunction in comparison with the other two hybrids with type-I heterojunction. The kinetic constant over AgBr/Ag2CrO4 NR hybrids is 4 times as high as the pure Ag2CrO4 NRs, which demonstrates that the formation of heterojunction is beneficial for suppressing the recombination of photogenerated holes and electrons. Moreover, the radO2− and h+ are proven to be main active species involving in the photocatalytic degradation of phenol. Apart from that, chlorine radicals are found to be produced simultaneously to enhance photocatalytic activity of AgCl/Ag2CrO4.

Application of traditional bait in aquaculture caused environment pollution and disease frequent occurrence. Residual papaya could be re-utilized to culture Tilapia mossambica as dietary supplement. Therefore, a novel integrated system of the improvement of yield, antioxidant and nonspecific immunity of Tilapia mossambica by dietary residual papaya was proposed and investigated. Tilapia mossambica could grow well in all supplement residual papaya groups. Survival rate, yield, whole fish body composition under 15–45% groups were increased compared with control group (CK). Bioactive substances (polyphenols and vitamin) in residual papaya enhanced ALP, ACP, phagocytic, SOD, CAT activities through up-regulating ALP, ACP, SOD, CAT genes expression levels. Theoretical analysis showed bioactive substances regulated these genes expressions and enzyme activities as stimulus signal, component, active center. Moreover, residual papaya improved mTOR and NF-kB signaling pathway. Furthermore, residual papaya inhibited Aeromonas hydrophila that increased resistance to diseases. This technology completed the solid waste recovery and the Tilapia mossambica growth performance simultaneously.

Application of traditional bait in aquaculture caused environment pollution and disease frequent occurrence. Residual coconut could be re-utilized to culture Spinibarbus sinensis as dietary supplement. Therefore, a novel integrated system of the improvement of yield, antioxidant and nonspecific immunity of Spinibarbus sinensis by dietary residual coconut was proposed and investigated. Spinibarbus sinensis could grow well in all supplement residual coconut groups. Survival rate, yield, whole fish body composition under 15–45% groups were increased compared with control group (CK). Bioactive substances (polyphenols and vitamin) in residual coconut enhanced AKP, ACP, phagocytic, SOD, CAT activities through up-regulating AKP, ACP, SOD, CAT genes expression levels. Theoretical analysis showed bioactive substances regulated these genes expressions and enzyme activities as stimulus signal, component, active center. Moreover, residual coconut improved mTOR and NF-kB signaling pathway. Furthermore, residual coconut inhibited Aeromonas hydrophila that increased resistance to diseases. This technology completed the solid waste recovery and the Spinibarbus sinensis culture simultaneously.

Various morphologies and structure properties of CeVO4 photocatalysts were prepared via ethylene glycol (EG)-aided hydrothermal method and characterized by XRD, SEM, EDX, TEM, XPS, UV–Vis diffuse reflectance, PL emission and transient photocurrent responses, respectively. The influence of EG content on morphology and structure of as-prepared samples was examined as regard the photodegradation performance of naphthalene (Nap) in natural seawater. The results showed that Ce2 (CeVO4) sample with 10 mL EG addition exhibited the highest photodegradation efficiency of Nap, because the fusiform morphology of Ce2 sample favored the transportation of visible light and the separation of photoexcited carriers. In addition, the possible intermediate products were detected by FTIR, 3D fluorescence and GC–MS and the results showed only one mechanism of Nap direct conversion to CO2 and H2O was include in the photocatalytic reaction by Ce2 sample. The active species were detected by ESR and trapping experiments and the results showed that ∙OH played a more significant role in the photochemical degradation. Finally, the possible photodegradation mechanism of Nap over Ce2 sample was proposed on the basis of intermediate products and the active species formed in photodegradation process, and Ce4+/Ce3+ redox centers of Ce2 sample was performed under the irradiation of visible light.

A novel cobalt monoxide/tungsten trioxide p-n heterojunction was fabricated via a two-step hydrothermal method for improving the photocatalytic activity for gaseous pollutant degradation and oxygen evolution. The TEM characterization results indicated that the CoO nanoparticles with diameter of 30 nm were uniformly distributed on the surface of WO3 nanoplates, which not only increased the light absorption efficiency but also promoted charge separation efficiency owing to a formed internal electric field in p-n junction hybridized system. In all samples, 15 wt% CoO/WO3 displayed the highest photocatalytic activity, where the degradation conversion of toluene achieved to 85.4% in 4 h, which were 2.0- and 20.3-folds higher than that of WO3 and CoO, respectively. Besides, the as-prepared CoO/WO3 composite also exhibited significantly increased photocatalytic oxygen production under visible light irradiation. Moreover, by in-situ infrared spectra, the main intermediate products, including benzyl alcohol, benzaldehyde, benzoic acid and formate or acetate were clearly clarified at the interface over the catalysts. Combined with the ESR, VB-XPS and UPS, a possible mechanism for the photocatalytic process over the CoO/WO3 p-n heterojunctions were proposed and discussed.

Background Sevoflurane and isoflurane had been reported to improve ischemia/reperfusion injury (I/R) through amelioration of the inflammatory response. We aimed to explore and compare the molecular mechanisms involved in sevoflurane and isoflurane anesthesia in liver ischemia-reperfusion of rat model. Methods Forty male Wistar rats were randomly divided into 4 groups: sham group, I/R group, sevoflurane group, and isoflurane group. The liver I/R injury model was established to investigate the effect of sevoflurane and isoflurane anesthesia on liver ischemia/reperfusion. The inflammatory markers and complement C3, C5a, and C6 were detected by enzyme-linked immunosorbent assay. Oxidative stress was detected by measuring the levels of malondialdehyde (MDA), superoxide dismutase (SOD), and nitric oxide (NO). Results Our results showed that sevoflurane anesthesia significantly decreased alanine transaminase, aspartate transaminase, and lactate dehydrogenase levels compared with isoflurane and controls. Sevoflurane inhibited I/R injury induced production of tumor necrosis factor α, interleukin 1, interleukin 6, and intercellular cell adhesion molecule-1 and promoted interleukin 10 production more significantly compared with isoflurane. Reduced MDA and NO and elevated SOD release suggested that oxidative stress was attenuated by sevoflurane and isoflurane anesthesia. Both sevoflurane and isoflurane anesthesia significantly decreased plasma C3 levels compared with the I/R injury group without differences. Conclusion Sevoflurane anesthesia produced a more significant inhibitive effect on inflammatory cytokines and oxidative stress in liver I/R injury model than isoflurane, suggesting that sevoflurane is more suitable in surgery.

Sensors are of increasing interest since they can be applied to daily life in different areas from various industrial sectors. As a natural nanomaterial, nanocellulose plays a vital role in the development of novel sensors, particularly in the context of constructing multidimensional architectures. This review summarizes the utilization of nanocellulose including cellulose nanofibers, cellulose nanocrystals, and bacterial cellulose for sensor design, mainly focusing on the influence of nanocellulose on the sensing performance of these sensors. Special attention is paid to nanocellulose in different forms (1D, 2D, and 3D) to highlight the impact of nanocellulose constructed structures. The aim is to provide a critical review on the most recent progress (especially after 2017) related to nanocellulose-containing sensors, since there are significantly increasing research activities in this area. Moreover, the outlook for the development of nanocellulose-containing sensors is also provided at the end of this work.

In this paper, in order to expand the light response range of TiO2, Ag3VO4/TiO2 nanorods photocatalysts were fabricated by a simple sol–gel method with microwave and hydrothermal method. The as-prepared samples were characterized by XRD, SEM, DRS, XPS and N2 adsorption–desorption. Meanwhile, their photocatalytic properties were investigated by the degradation of toluene under visible light irradiation. The degradation conversation of toluene had gotten to about 70% in 1% Ag3VO4/TiO2 nanorods after reaction 4 h. The predominant photocatalytic activity can be attributed to its strong absorption in visible light region and excellent charge separation characteristics. By using in situ FTIR, benzyl alcohol and benzaldehyde species could be observed during the reaction and the formed intermediates would be partially oxidized into CO2 and H2O. Electron spin resonance confirmed that OH and O2 − were involved in the photocatalytic degradation of toluene.

In order to enhance the photocatalytic activity of g-C3N4 in the visible light region, BiPO4/g-C3N4 nanocomposites photocatalysts with different BiPO4 contents were prepared through a hydrothermal method including calcination. Through N2 adsorption–desorption measurements, BiPO4/g-C3N4 showed a large surface area (172.9 m2 g−1) and small pore diameter and the incorporation of BiPO4 caused a red-shift of g-C3N4 in the visible light region by UV-vis diffuse reflection spectroscopy. The photocatalytic degradation of benzene over BiPO4/g-C3N4 was investigated. Degradation of benzene could be achieved up to 73% in 2 wt% BiPO4/g-C3N4 photocatalysts under optimum reaction conditions, which was 6 times more when compared with pure g-C3N4 at the same conditions. The improved photoactivity of BiPO4/g-C3N4 could be ascribed to its effective separation of photogenerated hole–electron pairs between BiPO4 and g-C3N4. Furthermore, the BiPO4/g-C3N4 photocatalysts showed excellent stability. By using an in situ FTIR technique, ethyl acetate, carboxylic acid and aldehyde could be regarded as the intermediate products, and CO2 and H2O were produced as the final products. Through electron spin resonance (ESR), OH˙ and O2˙− were examined in the photocatalytic degradation of benzene.

BiPO 4 /g-C 3 N 4 with different amounts of BiPO 4 was prepared through wet impregnation with calcination method. The BiPO 4 /g-C 3 N 4 showed large surface area (172.9 m 2 g − 1 ) and the incorporation of BiPO 4 caused a red-shift of g-C 3 N 4 in visible light. The photocatalytic degradation of toluene over the samples was investigated. The degradation of toluene could get 82% in BiPO 4 /g-C 3 N 4 photocatalysts under optimum reaction conditions. The BiPO 4 /g-C 3 N 4 exhibited a higher photocatalytic activity than pure g-C 3 N 4 or BiPO 4 . The improved photoactivity of BiPO 4 /g-C 3 N 4 could be attributed to strong absorption in visible light and effective separation of photo-induced hole-electron pairs between BiPO 4 and g-C 3 N 4 .

Three-dimensional (3D) printing is classified as a revolutionary, disruptive manufacturing technology. Cellulose (the most abundant natural polymer) and its many derivatives have been widely studied for many applications. The combination of 3D printing with cellulose-based feedstocks is therefore of critical interest. This review highlights many studies on 3D printing applications of plant-derived cellulose and its derivatives. Potential materials include cellulose ethers/esters, microcrystalline cellulose, nanocellulosic materials, and other products. It focuses on their roles and functions in 3D printing processes and the performance of the resultant printed objects. The outlook for future work is also provided, to underscore critical issues and opportunities.

There has been increasing concern regarding environmental problems arising from the widespread use of petroleum-based plastic materials for packaging. Many efforts have been made to develop sustainable and biodegradable packaging materials to replace plastic products. The current review summarizes recent research progress in developing cellulose packaging materials to replace plastics used for cushioning and barrier packaging functions based on pulp fibers, cellulose nanofibers, and regenerated cellulose films to benefit from their renewability, sustainability and biodegradability. The cushioning packaging materials include molded pulp products and bio-based foams. Advanced cellulose films and paper can be good barriers for oxygen and carbon dioxide gases, as well as for water vapor. Several cellulose fiber-based packaging products have been commercialized in areas that used to be occupied solely by plastic products.

Deacidification refers to chemical treatments meant to slow down the acid hydrolysis and embrittlement of books and paper documents that had been printed on acidic paper. From the early 1800s up to about 1990, papermakers used aluminum sulfate, an acidic compound, in most printing papers. Certain deacidification methods use non-aqueous media to distribute alkaline mineral particles such as MgO within the pages of the treated books. Evidence is considered here as to whether or not the proximity of alkaline particles within such documents is sufficient to neutralize the acidic species present. Because much evidence suggests incomplete neutralization, a second focus concerns what to do next in cases where books already have been treated with a non-aqueous dispersion system. Based on the literature, the neutralization of acidic species within such paper can be completed by partial moistening, by high humidity and pressure, by water condensation, as well as by optional treatments to enhance paper strength and a final drying step.

The effects of coating formulation on thermal characteristics of coating layers (namely thermal diffusivity, specific heat capacity and heat conductivity) were systematically studied and their impact on xerography print quality was evaluated. Model coatings were prepared using ground calcium carbonate or kaolin pigment mixed with styrene butadiene latex binder in various proportions (from 6 to 25 pph). As expected, porosity was shown to be a key parameter for thermal conductivity of the coating layers, and is mainly determined by the latex concentration. Particle size distribution (PSD) and pigment morphology also affected the thermal characteristics of the coating layers. It was found that the bulk thermal conductivity of the coating layers can be accurately predicted by a geometric mean model based on the pigment, latex and air contents. Print quality on model coated papers was evaluated in terms of print gloss, toner adhesion and pairwise visual ranking. It was demonstrated that print gloss is improved by decreasing the bulk thermal conductivity of the coatings. The coating formulated with the pigments with the steepest PSD and 10 pph of latex had a relatively low thermal conductivity and the best print quality.

In this work, Ag-doping TiO2 nanotubes were prepared and employed as the photocatalyst for the degradation of toluene. The TiO2 nanotube powder was produced by the rapid-breakdown potentiostatic anodization of Ti foil in chloride-containing electrolytes, and then doped with Ag through an incipient wetness impregnation method. The samples were characterized by scanning electron microscope, high-resolution transmission electron microscopy. X-ray diffraction, surface photovoltage measurements, X-ray photoelectron spectroscopy and N-2 adsorption. The nanotubular TiO2 photocatalysts showed an outer diameter of approximately 40 am, fine mesoporous structure and high specific surface area. The photocatalytic activity of Ag-doping TiO2 nanotube powder was evaluated through photooxidation of gaseous toluene. The results indicated that the degradation efficiency of toluene could get 98% after 4 h reaction using the Ag-doping TiO2 nanotubes as the photocatalyst under UV light illumination, which was higher than that of the pure TiO2 nanotubes, Ag-doping P25 or P25. Benzaldehyde species could be observed during the photocatalytic oxidation monitored by in situ FTIR, and the formed benzaldehyde intermediate during reaction would be partially oxidized into CO2 and H2O. (C) 2011 Elsevier Ltd. All rights reserved.

Differently sized Cu2O nanoparticles have been assembled photocatalytically on the surface of self-organized highly oriented TiO2 nanotubes obtained by anodization of a Ti sheet in fluoride-containing electrolytes. X-ray diffraction analysis identifies an anatase structure and fine preferential orientation of (101) planes. The UV-vis absorption edge of the TiO2 nanotube arrays shift to lower energy after Cu2O loading. The composite array electrode exhibits a higher photovoltage response than the TiO2 powders directly deposited on a Ti sheet. The highest photoconversion efficiencies observed for the Cu2O-loaded electrode are 17.2% and 0.82% under UV light and visible light irradiation, respectively. Especially, the composite array electrode shows a higher efficiency than the nonloaded one for the photoelectrocatalytic decomposition of 4-chlorophenol. The improved photoeletrocatalytic activity of the TiO2/Cu2O composite array electrode is attributed to the synergistic effect of Cu2O nanoparticles and TiO2 nanotube arrays. The Cu2O nanoparticles could enhance the efficiency of photon harvesting and reduce the chances of electron-hole recombination by sending the electrons to the conduction band of TiO2 nanotubes. The accumulated electrons in the conduction band of TiO2 nanotubes would reduce oxygen to form peroxides for enhanced advanced oxidation. The byproducts were identified by high-performance liquid chromatography.

Developing photocatalysts with specific morphology promises good opportunities to discover the geometry-dependent properties. Herein, flower-like anatase TiO2 assemblies with dominant {001} facets exposed were successfully synthesized via a simple, economical hydrothermal route with titanium sulfate and hydrofluoric acid. Their surface morphology and structure were investigated by scanning electron microscopy, transmission electron microscopy, selected area electron diffraction, X-ray diffraction, and Brunauer–Emmet–Teller N2 gas adsorption–desorption isotherms. The optical property and the photo-induced charge carriers of the flower-like TiO2 were studied by UV–vis diffuse reflectance spectroscopy and transient photovoltage technique. The flower-like TiO2 particles exhibited a good photocatalytic activity in degrading rhodamine B.

ACCELERATED AGING OF PAPERS OF PURE CELLULOSE - MECHANISM OF CELLULOSE DEGRADATION AND PAPER EMBRITTLEMENT