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Herein, a novel CdIn2S4/In2O3 heterojunction photocatalyst, aiming to enhance photocatalytic performance for pollutant degradation, is fabricated by a self‐assembly process at low temperature. Ternary CdIn2S4 nanoparticles are uniformly deposited on the In2O3 nanoflowers, forming a step‐scheme (S‐scheme) hybrid heterostructure. As a result, the light absorption efficiency and charge separation efficiency of CdIn2S4/In2O3 are greatly improved. Among these fabricated samples are activated by visible light, and the degradation efficiency of gaseous acetone is as great as 92.3% over 10% CdIn2S4/In2O3 within 3 h, which is the highest value observed. Furthermore, the key intermediate compounds are elucidated using in situ Fourier transform infrared (FTIR) spectra, which strongly validate the hypothesized light degradation mechanism over CdIn2S4/In2O3. Correspondingly, a potential photocatalytic mechanism over CdIn2S4/In2O3 S‐scheme heterojunction is explored and discussed.

Pollutant discharge causing the deterioration of the watershed environment has seriously threatened human health and ecosystem function. The importance of improving the risk warning system is becoming more and more prominent. Traditional chemical risk assessment methods focused on toxicity and the exposure of pollutants without considering the impact of persistent pollutants in different environmental media. In this study, a new approach was proposed to reflect multi-dimensional evaluation with a synthetic risk factor (SRF) of pollutants. The integrating parameters of SRF include toxicity endpoint values, environmental exposure level, persistent properties, and compartment features. Selected pesticides, perfluorinated compounds, organophosphate esters and endocrine disruptors were analyzed by the proposed and traditional methods. The results showed a higher risk outcome using SRF analysis for PFOS, imazalil, testosterone, androstenedione and bisphenol A, which were different from those obtained by the traditional method, which were consistent with existing risk management. The study demonstrated that the SRF method improved the risk assessment of various pollutants in different environmental media in a more robust fashion, and also provided a more accurate decision basis for ecological environment protection.

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

The efficiency of optical brightening agents (OBAs), also known as fluorescent whitening agents (FWAs), has long been of interest in the production of uncoated fine paper, particularly in uncoated fine paper grades containing high-yield pulp (HYP). The increasing levels of whiteness and also the increasing HYP substitution in fine papers has made OBA efficiency an important issue. This paper summarizes recent research findings in understanding and enhancing OBA efficiency in fine papers containing HYP, with focus on the main factors affecting OBA efficiency in both wet end and size press application. These factors include the base sheet brightness and whiteness of the pulp, UV competitors, OBA retention, quenching effects, and OBA migration at the size press. Some new technologies to improve OBA efficiency are discussed.

With the expansion of software system scale, the study of software complexity has become a hot topic in software engineering. However, the domestic research on software complexity analysis technology is not mature, especially the measurement and evaluation methods of software complexity are not perfect. In order to solve the problem of prediction and evaluation of program structure complexity in software engineering more effectively, this paper proposed a program complexity measurement technique based on OINK framework. The technology uses the data sharing interface design to analysis target program by extracting the complex relationship between OINK components. On this basis, the technology adopts the layered software architecture to realize the automatic design of the function of the measurement data acquisition module, the complexity measurement module and the data management module of measurement results, thus, the structure complexity of the target program can be analyzed more clearly and accurately. At the same time, this technique applies multiple measurement methods to quantify the complexity of program structure, such as McCabe, HalStead, and Line Count. Experimental results show that this method can effectively measure the complexity of program structure. The solution on software complexity based on the open source ONIK framework will be open up worldwide, and will be continuously supported and improved by global communities and teams under the constraints of common driving forces. [ABSTRACT FROM AUTHOR]

Activated sludge (AS) bulking is a thorny problem which leads to serious issues in municipal sewage treatment plant (MSTP). An approach based on the margin of safety (MOS) was proposed to alarm AS bulking. Chemical oxygen demand (COD) serving as a representative chemical index for effluent was introduced to obtain the MOS. It was shown that the area of observation was divided into safety, alarm, and risk zones by the MOS with a range of COD between 25.63 and 50.00 mg L–1. The MOS of invertase under the influence of bisphenol A and triclosan was 534.40~902.59 mg L–1 and 904.91~1,870.81 mg L–1, respectively. The goodness of fit to the practical situations for the MOS of COD in several MSTPs was further certified. The MOS-based method using different types of indicators to predict AS bulking demonstrated many advantages of precision, ease-of-use, and feasibility in complex situations. The findings in this work are valuable to evaluate the environmental risks of emerging organic contaminants and the disturbance risks of sewage treatment processes. [ABSTRACT FROM AUTHOR]

The mechanisms of reactive blue (RB) photodegradation under simulated solar irradiation in different systems has been studied. The results show that [H2O2]0 was the determining factor for light/ H2O2/Fe(III) system in decomposing RB. The pH value has a significant effect on H2O2/Fe(III) system. At pH values of 3, 4, 5 and 6, the removal efficiencies of RB were 61%, 49%, 43% and 39%, respectively. Further, the role of humic acid (HA) was examined. The pH range of H2O2/Fe(III) system was extended by the existence of the HA. The mechanisms of RB photodegradation by H2O2/Fe(III)/ HA systems included 4 pathways: the hydroxyl radical (•OH) produced from irradiated H2O2/Fe(III) system, the •OH produced from irradiated H2O2/Fe(III)/HA system, the adsorption by Fe(III)-HA complexes and the other reactive species produced from light/H2O2/Fe(III)/HA system. Overall, the •OH leading to RB degradation was the major pathway and accounted for about 72% of the total RB degradation. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In economic and environmental point, sludge drying reed beds (SDRBs) are regarded as a sustainable technology for sludge stabilization. In this study, we determine the effects of the final product from SDRBs used as sandy soil conditioner Sludge fertilizer application caused beneficial effects on soil nutrients, which significantly increased total phosphorous (TP), plant-available phosphorous (AP), alkali hydrolyzable nitrogen (AHN), and organic matter per kilogram soil as the increasing of the sludge fertilizer and soil ratios. Bacteria values of E. coli of amended soil showed a clear decreasing trend, and met the Standard of Pollutants Discharge in Urban Sewage Treatment Plant in China (GB18918-2002). The application of sludge fertilizer did not bring substantial influence on fungi type and quantity in soil. The height of plant grown on sludge amended soil was taller in total than the controls. The yields of soybean were improved by compared to the unamended soil. Crude protein and crude fat contents of soybean were slightly higher in amended soil than those in the controls except the lowest dose. The study demonstrates good efficiency of sludge fertilizer from SDRB in sandy soil amendment and its potential application in agricultural land in the future. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A pilot-scale constructed wetland was tested for the disposal and stabilization of sludge from a municipal wastewater treatment plant. The accumulation and distribution of sixteen polycyclic aromatic hydrocarbons (PAHs) in the plants of Phragmites australis grown on the wetland receiving the sludge was investigated in comparison with native plants without the sludge to examine the effectiveness using P. australis as PAHs bioaccumulator. The experiment lasted for three years and divided into three phases: year 1 was adjustment phase; year 2 was operational phase; year 3 was natural stabilization phase. Analysis of the distribution of PAHs in native P. australis showed that the sequence of PAHs content in the plants was leaves > stems > roots at 2583, 2198 and 899 βg/kg (DW), respectively. After two year load and one year natural stabilization, the PAHs content in the loaded sludge declined by 63%; the tested plants in the constructed wetland accumulated much more PAHs than native plants. The bioconcentration factor (BCF) of leaves was slightly higher than that of roots and stem i.e. 3.759, 3.518 and 3.368, respectively. The respective PAHs contents in the roots, stems and leaves of the tested P.australis were 7313, 7002 and 7814 βg/kg (DW), being 8.13, 3.19 and 3.02 times of that in the native one, respectively. The BCF of roots and stems of the low molecular weight (MW) PAHs (2-3 ring PAHs) predominated as 5.02 and 4.93 in all samples from the constructed wetland, while the BCF of middle-MW PAHs (4 ring PAHs) was 3.15 and 2.1, and that of high-MW PAHs (5-6 ring PAHs) was 2.29 and 2.63, respectively. In the leaves, the BCF of low-MW and middle-MW PAHs was 4.03 and 4.17, which was higher than 2.81 of high-WM PAHs. The results demonstrated that this plant can effectively remove PAHs from the sludge discharged to the wetland. [ABSTRACT FROM AUTHOR]

With increased interest in using high-yield pulps (HYP) in uncoated and coated wood-free paper, there is a need to evaluate the effects of HYP under the conditions similar to commercial paper machine operations. Such tests were carried out by means of a Dynamic Sheet Former (DSF) sheet with white water recirculation, considering the high fines content of HYP and the usually high filler content in fine papers. In this study, we evaluated the use of a DSF that is equipped with a white water recirculation tank for making oriented sheets under various conditions. The effects of different factors such as operational variables, use of retention aids, and recirculation of white water were examined and clarified in terms of retention of fines and fillers as well as their impact on paper properties. The effect of HYP content on filler retention was also examined. [ABSTRACT FROM AUTHOR]

The article reports on the paper coating properties as affected by pigment blending and calendering. Coating colors with different blending ratios of ground calcium carbonate (GCC) and clay with a similar particle size distribution using a constant level of binder and co-binder were applied on plastic films and calendered them using a paper sheet. Mercury porosimetry, atomic force microscopy, gloss, and spectrophotometric measurements were the qualities of the coating layer structures. The process showed that synergy occurs for pore volume, pore size, and light-scattering coefficient when combining GCC and clay and that the property from a pigment blend can be higher than what is predicted from simple additivity.

The article discusses the study which examines the effect of high-yield pulp (HYP) substitution on the properties of basestock, coated and calendered sheets in lightweight coated (LWC) wood-free papers. Researchers have provided results on several tests on coated properties including surface quality, coating coverage and printability. It has been found out that after coating and lightweight coated, the increased bulk created by HYP substitution is partially preserved. In addition, researchers assert that substitution of hardwood kraft pulp with aspen HYP up to 20% in LWC wood-free papers could increase the bulk without harmful effect on the coated paper quality.

The article investigates the effects of substituting high-yield pulp (HYP) for hardwood bleached kraft pulp (HBKP) on the basestock properties. The two main furnishes in traditional wood-free coated papers were HBKP and softwood bleached kraft pulp (SBKP). Study showed that the effects of HYP substitution has reduced the Canadian Standard Freeness by 30 percent of the blended furnish. The author recommends that the substitution of hardwood kraft with aspen HYP by 30 percent is technically practicable and beneficial to produce lightweight wood-free basestock.

High-yield pulp can replace hardwood kraft in wood-free coated papers to increase bulk and reduce costs. This research was undertaken to study the effects of pulp substitution on brightness stability. Light-induced brightness loss was found to occur as a result of both high-yield pulp substitution and the yellowing of the coating color. However, coating improves the brightness stability. The improvement can be significant, depending on the extent of pulp substitution and the coat weight. For a 15% substitution of high-yield pulp, a coat weight of 20 g/m² gave the same brightness stability as a 100% kraft sheet coated at 4 g/m². An empirical model was developed to estimate the effect of high-yield pulp and coat weight on the brightness stability of wood-free coated papers. [ABSTRACT FROM AUTHOR]

What is the effect on alkyl ketene dimer (AKD) sizing of substituting aspen high-yield pulp for hardwood kraft pulp? The degree of sizing was found to be higher for sheets containing high-yield pulp than for sheets made without it. The addition of pelyethyleneimine (PEI) prior to AKD addition further improves the degree of AKD sizing of sheets containing high-yield pulp. PEI was added to the high-yield pulp alone as well as to a mixture of high-yield pulp and kraft pulps. Differences in sizing efficiency between these two approaches were attributed to the two distinct functions of PEI: neutralization of anionic trash in the high-yield pulp and sizing promotion for AKD. Precipitated calcium carbonate (PCC), used as filler, had an adverse effect on AKD sizing of sheets made both with and without high-yield pulp. Application: High-yield aspen pulp can be used as a substitute for part of the hardwood kraft pulp without any loss of sizing efficiency. [ABSTRACT FROM AUTHOR]