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Under stressful conditions, bacteria can enter viable but non-culturable (VBNC) state to survive. VBNC cells lost ability to grow on routine culture medium but are still alive and may revive in suitable conditions. The revived cells can consume nutrients or produce toxins, leading to food spoilage or human illness, posing great risk to food safety and public health. Previously, we have reported that high pressure carbon dioxide (HPCD), an environment-friendly sterilization technology, can induce VBNC formation. However, the underlying mechanism is unclear. By performing a comprehensive transcriptomic analysis, we revealed that HPCD initiated high expression of asr, encoding an acid shock protein, could promote VBNC formation of E. coli O157:H7. Quantitative reverse transcription PCR analysis suggested that high expression of asr (i) inhibited acid resistance (AR) systems, resulting in endogenous proton accumulation; (ii) inhibited hchA expression, a protein stabilizing factor. The two effects resulted in endogenous protein aggregation, which was highly correlated to VBNC formation. Accordingly, HPCD-stressed cells exhibited decreased efficiency of electron transfer chain and ATP production, which was also contributory to cytoplasmic protein aggregation. Taken together, HPCD-initiated high expression of Asr coupled with decreased ATP production led to protein aggregation, finally promoted the cells to enter VBNC state.

There are global trends for developing green and sustainable technologies in food processing, due to the growing awareness of the importance of environmental preservation and the consumer demand for natural high-value food products. Meeting these particular requirements, supercritical carbon dioxide (SC-CO2) has emerged as an innovative and promising technology for the processing of food ingredients and products. Over the last two decades, applications of SC-CO2 have attracted much attention and made great advancements at both laboratory and industrial level. These advances include the extraction of target bioactive compounds from various food matrices, microencapsulation, or extrusion to produce fine particles, and the inactivation of pathogenic and spoilage microorganisms and endogenous enzymes for food preservation. An example of successfully applying SC-CO2 at the commercial level is the decaffeination of coffee. In this article, an overview of the SC-CO2 applications in food processing including extraction, transformation, preservation, and drying are presented. For each application category, principles, processing parameters, characteristics, and latest applications are critically reviewed.

Broflanilide (BFL) is a new type of pesticide with broad prospects. However, it is not yet fully understood. With its wide application in the paddy field, it might pose a threat to the environment. Therefore, it is necessary to research its environmental behaviors including adsorption-desorption and leaching behaviors in the soil to evaluate its risks on that basis. Soil samples were obtained from the farmland surface layer in four different regions of China. Adsorption-desorption experiments were conducted according to the equilibrium oscillation method and OECD guidelines. Leaching experiments were designed on the basis of the OECD guidelines. Based on the guidelines of CIPAC, the proposed method was verified and calibrated. BFL residue was analyzed using UHPLC-ESI-QTOF-MS. The Freundlich model was used to fit the BFL’s adsorption-desorption parameters in all soil samples with adsorption constant of BFL ranging from 0.152 to 5.017. The decreasing trends of the BFL adsorption capacity are Phaeozems > > Anthrosols > Gleysols > Luvisols. A linear positive correlation of BFL’s Freundlich desorption and adsorption between organic matter content (R2 = 0.893 and 0.851) and soil clay content (R2 = 0.765 and 0.686). Nevertheless, nonsignificant relationships (R2 = 0.428 and 0.384) between the BFL parameter and the cation exchange capacity of soils were observed. Moreover, soil pH exhibits negative relationships (R2 = 0.095 and 0.089) with BFL’s adsorption and desorption constants. Furthermore, either above or below 287 K reduced the adsorption capacity of BFL by soil. The leaching of BFL in Anthrosols, Gleysols, and Luvisols was easy, while difficult for Phaeozems. Except for Phaeozems which contain high organic matter, BFL posed threats to groundwater and surface water owing to their either intermediate or high mobility within the soils in the agriculture system.

Polyphenol oxidase (PPO)-mediated enzymatic browning occurs in fruit, vegetables and aquatic products and causes huge economic losses every year. In this study, epigallocatechin-3-gallate (EGCG) displayed high affinity for and efficient inhibitory capacity against PPO. To explore the inhibition mechanism, multispectroscopic methods and computational simulations were implemented. Initially, EGCG inhibited PPO activity reversibly in a mixed-type manner. Then, the conformation and secondary structure changes of PPO after binding with EGCG were discovered by fluorescence emission spectra and circular dichroism. Molecular docking and dynamic simulation results revealed that EGCG could tightly bind with the binuclear copper domain of PPO through hydrophobic stacking and hydrogen bonds. Moreover, EGCG might act as a linker to interact with different PPO molecules at another binding site. Transmission electron microscopy observation suggested that EGCG induced the aggregation of PPO. Therefore, the inhibition mechanism of EGCG on PPO included competition for catalytic centers and induced aggregation.

Potato starch (PS), a natural and structured semicrystalline polymer, exhibits a distinct capacity to bind cyanidin-3-O-glucoside (C3G) at different pH values (3, 5, and 7). In this study, levels of NaCl (0.05%, 0.5%, and 5%, w/v) were introduced as electrostatic disturbing agents to the PS-C3G complexes to quantitatively reveal the role electrostatic interactions played in the binding at different pH conditions. The binding rate dropped from 31.60% to 2.19% as the pH value shifted from 3 to 7, indicating a decreasing affinity from C3G to PS. Further zeta potentials showed the possibility of electrostatic interactions in the PS-C3G complexes at pH 3 as well as screened charges in the presence of NaCl. The binding rate at pH 3 then exhibited a progressive decline to a final approximate one-third as the concentration of NaCl increased, which implied that the electrostatic interactions constituted the primary two-thirds of the driving forces involving complex stability at pH 3. The results of attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, however, showed that hydrogen bonds had a negligible effect on the binding of C3G to PS at all pH conditions. Finally, the confocal laser scanning microscopy (CLSM) images, particle size and color differences were consistent with the change in the binding rate. Overall, electrostatic interactions were considered the key pH-modulated interactions between PS and C3G at different pH conditions.

The Gram positive bacterium Bacillus subtilis and its relatives are capable of forming a durable dormant long-lasting spore. Although spores can remain dormant for years, they possess the remarkable capacity to rapidly resume life and convert into actively growing cells. This cellular transition initiates with a most enigmatic irreversible event, termed germination, lasting only for a few minutes. Germination is typified by a morphological conversion that culminates in loss of spore resilient properties. Yet, the molecular events occurring during this brief critical phase are largely unknown. The current widely accepted view considers germination to occur without the need for any macromolecule synthesis; however, accumulating data from our laboratory and others, highlighted here, provide evidence that both transcription and translation occur during germination and are required for its execution. We further underline numerous overlooked studies, conducted mainly during the 1960s–1970s, reinforcing this notion. We propose to revisit the fascinating process of spore germination and redefine it as a pathway involving macromolecule synthesis. We expect our perspective to shed new light on the awakening process of a variety of spore-forming environmental, commensal, and pathogenic bacteria and possibly be applicable to additional organisms displaying a quiescent life form.

Based on the heterogeneous material model, an integrated analysis method was introduced to predict the service life of propeller. The morphology and distribution characteristic of non-continuous defects (porosity & inclusion) were calculated and mapped into the finite element model by 3D-mapping algorithm, and the fatigue life was predicted based on the heterogeneous material model. In this paper, the coupling analysis of casting process and fatigue prediction of marine propeller was done. The results show that porosity and mass inclusions in blade roots of propeller form serious heterogeneous characteristics in those parts, which increased the maximum stress of the propeller and decreased its theoretical fatigue life by 1/2, indicating that the effect of non-continuous defects on the service performance of casting is notable and cannot be ignored. Based on the integrated analysis method, the inference of the pouring temperature and gating system on the service life of propeller was studied further. The integrated analysis method brings the influence of the casting defects into structural analysis and fatigue analysis, which can improve the accuracy of the fatigue life prediction significantly.

A series of boron carbon nitride–pyromellitic dianhydride (BCNPA) composites were successfully synthesized for the first time, where BCNPA3 exhibited the best adsorption and photodegradation performances for tetracycline (TC) under visible-light irradiation. 1H NMR characterization confirmed the fact that BCNPA3 was formed via the dehydration reaction between the OH groups in BCN and COOH groups in PA. Elemental N in BCNPA3 could capture protons and increase the pH of the TC solution from 3.73 to 6.80; consequently, TC changed from the positive state (pH 3.73) to the neutral state (pH 6.80). Subsequently, the adsorption capacity of BCNPA3 for TC increased from 66.24 mg g−1 (at pH 3.73) to 74.66 mg g−1 (at pH 6.80). This may be attributed to the fact that these captured protons can work as adsorption sites, too. Furthermore, the photodegradation efficiency of BCNPA3 for TC at pH 6.80 under visible-light irradiation was also higher than that at pH 3.73 (95% vs. 87%), because TC at pH 6.80 is less stable than that at pH 3.73. More interestingly, Cr(VI) could only be photoreduced into Cr(III) by BCNPA3 under visible-light irradiation when it coexisted with TC. This could be attributed to the fact that the photodegradation of TC increased the separation efficiency of the photoinduced electron and hole; consequently, the photoinduced electrons had sufficient time to reduce Cr(VI). Photoinduced ˙O2− and holes had the main contribution toward TC photodegradation by BCNPA3, while photoinduced electrons were responsible for Cr(VI) photoreduction. The adsorption and photodegradation performances of BCNPA3 for TC and Cr(VI) could be easily recovered under visible-light irradiation.

Tumor necrosis factor (TNF-α) is capable of inducing apoptosis and is a promising candidate for genetic engineering drugs in cancer therapy; however, the serious side-effects of TNF-α hinder their clinical application. In the present study, a method for preparing fusion proteins of cell-penetrating peptides (CPP) and TNF-α (CTNF-α)-anchored exosomes coupled with superparamagnetic iron oxide nanoparticles (CTNF-α-exosome-SPIONs) with membrane targeting anticancer activity has been demonstrated. To acquire exosomes with TNF-α anchored in its membrane, a CTNF-α expression vector was constructed and a stable mesenchymal stem cell cell line that expressed CTNF-α was established. Conjugating transferrin-modified SPIONs (Tf-SPIONs) onto CTNF-α-exosomes through transferrin-transferrin receptor (Tf-TfR) interaction yields CTNF-α-exosome-SPIONs with good water dispersibility. The incorporation of TNF-α into exosomes and the conjugation of SPIONs significantly enhanced the binding capacity of TNF-α to its membrane-bound receptor TNFR I, thus increasing the therapeutic effects. CTNF-α-exosome-SPIONs significantly enhanced tumor cell growth inhibition via induction of the TNFR I-mediated apoptotic pathway. In vivo studies using murine melanoma subcutaneous cancer models showed that TNF-α-loaded exosome-based vehicle delivery enhanced cancer targeting under an external magnetic field and suppressed tumor growth with mitigating toxicity. Taken together, our results suggest that CTNF-α-exosome-SPIONs showed great potential in membrane targeting therapy.

In this study, composite pear juice was processed by ultra-high pressure homogenization (UHPH) at four different pressures (50, 100, 150, and 200 MPa) with six different temperatures (4, 20, 30, 40, 60, and 80°C), then microorganism and physicochemical and nutritional properties of the samples were investigated. The counts of total aerobic bacteria (TAB) and yeasts and molds (YM) were reduced by 0.89-4.72 log10 CFU/ml and 0.40-3.03 log10 CFU/ml after processing, respectively. There was no significant change on total soluble solid and color, but significant decreases of pH and particle size value were observed, and the antioxidant activity, total phenolic content, viscosity, and suspension stability significantly increased in treated samples. Compared to the untreated samples, polyphenol oxidase (PPO) and peroxidase (POD) activity of UHPH-treated samples varied between 97%-126% and 81%-165%, respectively, indicating that the PPO and POD activities could be inactivated or activated by UHPH. This study introduced proper temperature combined with UHPH could improve the microbial inactivation and the quality of the compound juice.

Inclusions are typical discontinuous defects, those defects significantly reduce the local mechanical properties of castings during solidification, and play a strong role in inducing and enhancing hot tearing in alloys. Based on the coupling characterization of micro solidification morphology and macro inclusions, this paper proposed a construction method of heterogeneous model containing multi-scale information, and carried out dynamic analysis on the evolution process of stress field at the end of solidification, so as to investigate the influence mechanism of inclusions on the initiation and propagation of hot tearing. The results showed that inclusions and their local content significantly changed the stress field at the end of solidification, which easily resulted in local stress concentration and induced crack source in defects area. During the crack propagation, nearby inclusions greatly reduced the propagation resistance and promoted the formation of hot tearing, which had significant impact on the propagation path of hot tearing. Introducing inclusions defect into stress analysis and comprehensively considering the induction and enhancement of inclusions on hot tearing can better improves the prediction accuracy of hot tearing, which has engineering guiding significance for casting process optimization and product quality control.

High hydrostatic pressure (HHP) is currently the most successful non-thermal processing technology for commercial applications, but with a drawback that it is difficult to effectively inactivate the pectin methylesterase (PME), which is critical to the stability of orange juice. In this study, the PME inhibition and mechanism by HHP (600 MPa/10 min) combined with epigallocatechin gallate (HHP-EGCG) treatment were investigated. Firstly, the HHP-EGCG treatment showed enhancement effect on PME inhibition in orange juice, and the samples maintained higher content of water soluble pectin and exhibited higher suspension stability than the HHP treated samples during 13 days of refrigerated storage. Secondly, after HHP-EGCG treatment, further synergistic effect was observed in the phosphate buffer system, and the greatest secondary structure transformation and fluorescence quenching of PME occurred. Finally, molecule docking suggested that EGCG could interact with the active sites of PME, and transmission electron microscope results revealed further aggregation of PME under HHP-EGCG treatment.

High pressure carbon dioxide (HPCD) has been used in food processing as a non-thermal pasteurization technology. However, the potential of HPCD to induce viable but non-culturable (VBNC) cells limits its application. The objective of this study was to explore the roles of extracellular pH of 3 (pH

Spores of wild-type Bacillus subtilis and some isogenic mutant strains were treated by high pressure CO2 (HPCD) at high temperature (HT) (HPCD + HT) at 20 MPa and 84-86 °C for 0–60 min, and centrifuged on a high density solution to obtain pelleted spores that retained CaDPA and light spores that lost CaDPA. All treated spores were analyzed for viability, and tested for germination, outgrowth, core protein damage, mutagenesis and inner membrane (IM) properties. The results showed that (i) with HPCD + HT treated spores, most pelleted spores and all light spores were dead; ii) a significant amount of dead HPCD + HT-treated spores that retained CaDPA germinated, but outgrowth was blocked; (iii) minimal mutants were generated in survivors of HPCD + HT treatment; (iv) the GFP fluorescence decrease in HPCD + HT-treated spores with high GFP levels was slower than spore inactivation; (v) the IM of HPCD + HT-treated spores that retained CaDPA lost its ability to retain CaDPA at 85 °C, and almost all of these spores' outgrowth in high salt was blocked; and (vi) HPCD + HT-treated spores that retained CaDPA germinated with l -valine or AGFK were almost all stained with propidium iodide. These results indicated that HPCD + HT inactivated B. subtilis spores by damaging spores’ IM, thus blocking spore outgrowth after germination.

The research on economic recession has been more focused on the interactions between macroeconomic and financial variables. However, whether material use has been affected during the recession period has remained under-explored. In order to fill up this gap, this study investigates the relationship between material use and economic recession, as well as other socio-economic drivers, by using the material flow analysis and the system generalized method of moments for 157 economies worldwide during 1980–2011. Results show that economic recession poses significant and negative impact on domestic material consumption at 1% level, illustrating its role as a determinant factor on material mitigation. By dividing the research sample into extractive and non-extractive economies, as well as high-, mid- and low-income groups, we again confirmed the significant negative correlations as expected. No significant sign is found between recession and physical trade balance. Besides, other drivers such as population, Gross Domestic Production (GDP) per capita and technological variables also exert marked effects at different situations. This research work provides an empirical study on how recession and other factors affect material use at various scenarios, which have essential implications for understanding material flow dynamics in different economic cycles.

A layered boron nitride (BN)–carbon nitride (CN) composite has been successfully synthesized by calcinating a mixture of BN nanoparticles and urea at 600 °C, wherein CN is formed from the thermal p...

Herein, we present the preparation of nano-TiO2–silicone resin composite films by double liquid phase spray deposition. The films exhibit better adhesion stability and photocatalytic activity under a hydrodynamic erosion condition than conventional nano-TiO2 composite films. The TiO2 layer morphology and effective TiO2 coverage ratio (CR) were affected by the initial curing time (ICT) of the silicone resin, e.g., the increase in an ICT from 10 to 40 min resulted in a CR change from 79.1 to 98.7%. The surface morphology evolution of composite films was studied under a hydrodynamic erosion period of 4 weeks. Obtained results allowed the 4-week evolution to be divided into four stages (pitting, crack pregnant, banded stripping, and surface stripping periods), additionally revealed that the CR of all samples was remained above 65%. The photocatalytic activity of composite films before and after 4-week hydrodynamic erosion was evaluated by rhodamine B degradation experiments. The 4-week erosion only led to the decrease of the photodegradation efficiencies by less than 40% in all cases. Thus, the fabricated TiO2–silicone composite films demonstrated excellent durability and photocatalytic activity under the conditions of long-term hydrodynamic erosion, allowing one to conclude that this work paves the way to the fabrication of next-generation photocatalytic materials for industrial applications.

The two essential terms in environmental sciences – dematerialization and decoupling – have always been controversial. This study aims to trace the evolution path on the methodologies, the evidence...

Isocycloseram is a new isoxazoline insecticide that can efficiently control the diamondback moth in cruciferous crops. The aim of this study was to establish a method for the determination of isocycloseram residues in/on cabbage and in the soil using HPLC-UV at 264 nm. A field test was conducted in December 2019 and 2020 to monitor isocycloseram dissipation in Jiangxi, China. Acetonitrile was used to extract isocycloseram from cabbage and soil. C18 and GCB were used to purify cabbage extracts, whereas soil extracts did not require purification. At the addition level of 0.01–1.0 mg/kg, the average recoveries in cabbage and soil were 91.81–109.95% and 89.89–104.08% respectively. After having applied 10% isocycloseram DC, isocycloseram dissipated faster in the cabbage matrix. Isocycloseram residues on cabbage leaves could be removed through simple cleaning methods, especially by soaking in 2% citric acid.

Temperature measurement is one of the keys to the normalization of prevention and control of COVID-19 in crowded places. However, there are still some shortcomings in the accuracy, real-time and safety of the current temperature measurement system. This paper aims to discuss the possibility of realizing a high-precision temperature measurement system based on the existing long-distance, real-time, passive terahertz imaging system: 1). The process of transmitting and converting terahertz energy radiated by a target with a certain temperature in the form of light, heat and electricity can be analyzed by using multi-physical field coupling models. The temperature measurement mathematical model of the terahertz imaging system can then be obtained; 2). The factors of measurement distance, atmospheric transmission and system radiation on the temperature measurement results can be considered, where the temperature models are established and converted into temperature coefficients respectively to compensate the measurement results and increase the temperature accuracy; 3). Based on the reference emitter correction algorithm and scene correction algorithm, the parameters of terahertz imaging channels can be adjusted and the system output image can be non-uniform corrected. By solving the key scientific issues like temperature calibration of image chroma values, temperature compensation under multi-factors, non-uniform correction of output images, it is possible to realize a high-precision, real-time and long-distance passive body temperature measurement system suitable for crowded places. We would like to obtain some frontier, key theoretical and innovative research results, and lay solid foundation and reserves key technology for the temperature measurement application of terahertz imaging system in crowded places.

High pressure processing (HPP) as a nonthermal processing (NTP) technology can ensure microbial safety to some extent without compromising food quality. However, for vegetative microorganisms, the existence of pressure-resistant subpopulations, the revival of sublethal injury (SLI) state cells, and the resuscitation of viable but nonculturable (VBNC) state cells may constitute potential food safety risks and pose challenges for the further development of HPP application. HPP combined with selected hurdles, such as moderately elevated or low temperature, low pH, natural antimicrobials (bacteriocin, lactate, reuterin, endolysin, lactoferrin, lactoperoxidase system, chitosan, essential oils), or other NTP (CO2 , UV-TiO2 photocatalysis, ultrasound, pulsed electric field, ultrafiltration), have been highlighted as feasible alternatives to enhance microbial inactivation (synergistic or additive effect). These combinations can effectively eliminate the pressure-resistant subpopulation, reduce the population of SLI or VBNC state cells and inhibit their revival or resuscitation. This review provides an updated overview of the microbial inactivation by the combination of HPP and selected hurdles and restructures the possible inactivation mechanisms.

Herein, we present a method for the quantitative analysis of broflanilide residues in water, soil, and rice samples from a paddy field in Jiangxi Province, China. The quick, easy, cheap, effective, rugged, and safe (QuEChERS) method was optimized for the extraction and purification of broflanilide residues. Residual broflanilide concentrations in different matrices were then determined by high-performance liquid chromatography (HPLC). The calibration curve of broflanilide showed good linearity in all matrices for concentrations between 0.005 and 1 mg·L−1, with a correlation coefficient greater than 0.99. The matrix effect varied from −69% to −54%, indicating matrix suppression. The average recoveries ranged between 85.82% and 97.46%, with relative standard deviations of 3.29%–8.15%. The limits of detection ranged from 0.16 to 1.67 μg·kg−1, and the limits of quantification were in the range of 0.54 to 5.48 μg·kg−1. Dissipation dynamic tests indicated broflanilide half-lives of 0.46–2.46, 2.09–5.34, and 1.31–3.32 days in soil, water, and rice straw, respectively. Broflanilide was dissipated more rapidly in water than in soil and rice straw. More than 90% of broflanilide residues dissipated within 14 days. The final residues of broflanilide in rice were all below LOQ at harvest.

The purification efficiency of the contaminants in the process of photocatalysis is influenced by the co-function of catalytic activity of materials, aquatic environment conditions and characteristics of transmission light. Here, tetracycline hydrochloride (TC-HCl) was introduced as the target pollutant, and the effects of different depths and TC-HCl concentrations on the transmission light intensity and spectral distribution were explored. The results show that incident light decreases with the increase of depth and pollutant concentration. The increase of depth influences the irradiance greatly, however, increase of concentration mainly lead to the narrow of transmission spectral range in the underwater field. The coupling relationship among pollutants, transmission spectral characteristics and photocatalytic reaction efficiency was discussed. Results show that the reduction of the underwater spectral range will reduce the effective response area of the material significantly, which directly leads to the reduction of pollutant removal efficiency in the degradation process. Aiming at different aquatic environment, photocatalytic materials with appropriate response spectral range should be selected to improve the light absorption ability, so that the removal efficiency can be improved significantly.

Basic oxygen furnace (BOF) slag was modified by adding 3.5% SiO2 and holding at 1673 K for 0, 5, 40, 90, 240, or 360 min. Kilo-scale modification was also carried out. The growth, stratification, and liberation of P-rich C2S in the modified slag were investigated. The optimum holding time was 240 min, and 90% of C2S grains were above 30 μm in size. The phosphorus content increased with holding time, and after modification, the phosphorus content in C2S was nearly three times higher than that in the original slag (2.23%). Obvious stratification of C2S was observed in the kilo-scale modification. Upper C2S particles with a relatively larger size of 20−110 μm was independent of RO (FeO-MgO-MnO solid solution) and spinel, which is favorable for liberation. Lower C2S was less than 3 μm and was embedded in spinel, which is not conducive to liberation. The content of phosphorus in upper C2S (6.60%) was about twice that of the lower (3.80%). After grinding, most of the upper C2S existed as free particles and as locked particles in the lower. The liberation degree of C2S in the upper increased with grinding time, from 86.02% to 95.92% in the range of 30−300 s, and the optimum grinding time was 180 s. For the lower slag grinding for 300 s, the liberation degree of C2S was 40.07%.

Jean Monet Network EU-China: Comparative experiences and contributions to global governance in the fields of climate change, trade and competition. Co-funded by Erasmus+ Programme of the European Union.

More than one hundred million tons of steelmaking slag is produced annually in China. Bad grindability inhibits efficiency of using steelmaking slag which resulted a great waste. In view of this situation, various methods were carried out to improve the grindability so that to reduce the amount of waste and recycle the materials. Experiments were executed to compare the self-pulverization rate before and after the modification and deoxidization. Our study results indicate that by using the method of modification and deoxidization, which improves the self-pulverization of slag could be greatly improved.

Basic oxygen furnace (BOF) slag was modified by adding 3.5% SiO2 and holding at 1673 K for 0, 5, 40, 90, 240, or 360 min. Kilo-scale modification was also carried out. The growth, stratification, and liberation of P-rich C2S in the modified slag were investigated. The optimum holding time was 240 min, and 90% of C2S grains were above 30 μm in size. The phosphorus content increased with holding time, and after modification, the phosphorus content in C2S was nearly three times higher than that in the original slag (2.23%). Obvious stratification of C2S was observed in the kilo-scale modification. Upper C2S particles with a relatively larger size of 20–110 μm was independent of RO (FeO-MgO-MnO solid solution) and spinel, which is favorable for liberation. Lower C2S was less than 3 μm and was embedded in spinel, which is not conducive to liberation. The content of phosphorus in upper C2S (6.60%) was about twice that of the lower (3.80%). After grinding, most of the upper C2S existed as free particles and as locked particles in the lower. The liberation degree of C2S in the upper increased with grinding time, from 86.02% to 95.92% in the range of 30–300 s, and the optimum grinding time was 180 s. For the lower slag grinding for 300 s, the liberation degree of C2S was 40.07%.

Revealing the spatio-temporal distribution of soil nitrogen (N) contributes to N management and prevention of N pollution. The objective of this work is to study the spatio-temporal distribution of soil N and their driving factors in the topsoil (0–20 cm) of farmland in Yugan county, China in 1982 and 2012. Data were collected from 200 sampling sites of the second national soil survey in Yugan in 1982 and 423 sampling sites of the soil testing and formula fertilization project in 2012. On average total N (TN) and available N (AN) significantly increased from 1.50 g kg−1 and 153.04 mg kg−1 in 1982 to 1.58 g kg−1 and 179.75 mg kg−1 in 2012, respectively. The distance of spatial autocorrelation for TN increased from 2.79 to 6.18 km and from 2.97 to 18.00 km for AN from 1982 to 2012. The nugget/sill ratio for TN (0.472 in 1982 and 0.581 in 2012) indicated that soil TN driving by natural characteristics in 1982 to human activities in 2012. The nugget/sill ratio for soil AN (0.471 in 1982 and 0.688 in 2012) indicated that soil AN is more influenced by human activities. The major factors driving the spatio-temporal distribution of soil N was N application rate. To promote the sustainable development of agriculture and eco-environment, we should improve the awareness of farmers on chemical fertilizers (particularly N) and the level of N fertilizer management, increase the use of manure and organic fertilizer and facilitate rational fertilization by farmers.

The effect of water activity (aw), as lowered by different dietary humectants, on the germination of Bacillus subtilis, Bacillus megaterium and Bacillus cereus spores with germinants that act by different mechanisms has been investigated and compared. Germination of spores of these species by all of the germinants investigated was inhibited as aw decreased, with the general order of efficacy for these non-ionic humectants being sucrose > trehalose > glycerol. The effect of lowering aw on germination by germinant receptor (GR)-dependent germinants was not appreciably altered by varying germinant concentrations, was generally not much more effective with spores lacking coats or an outer membrane, and was less pronounced with heat-activated spores. Analysis of the effect of aw on spore germination via different mechanisms showed that GR-dependent germination was least sensitive to aw, while germination via activation of spore cortex peptidoglycan hydrolysis or dipicolinic acid release was more sensitive. However, germination by high hydrostatic pressure was less sensitive to inhibition by low aw, than was germination by other germinants. Examination of the GR-dependent germination of individual spores indicated that aw acted most strongly in inhibiting the commitment step of germination, while exerting smaller effects on dipicolinic acid release or cortex peptidoglycan hydrolysis.

A TiO2/g-C3N4 composite photocatalytic film was prepared by in situ synthesis method and its photocatalytic capability under weak-visible-light condition was studied. The co-precursor with different ratio of melamine and TiO2 sol-gel precursor were treated using ultrasonic mixing, physical deposition, and co-sintering method to form the smooth, white-yellow, and compact TiO2/g-C3N4 composite films. The prepared TiO2/g-C3N4 materials were characterized by SEM, TEM, EDS, XRD, BET, VBXPS, and UV-vis diffuse reflectance spectra. The results of composite showed that TiO2 and g-C3N4 have close interfacial connections which are favorable to charge transfer between these two semiconductors with suitable band structure, g-C3N4 retard the anatase-to-rutile phase transition of TiO2 significantly, the specific surface area were increased with g-C3N4 ratio raised. Under weak-light irradiation, composite films photocatalytic experiments exhibited RhB removal efficiency approaching 90% after three recycles. Powders suspension degradation experiments revealed the removal efficiency of TiO2/g-C3N4 (90.8%) was higher than pure TiO2 (52.1%) and slightly lower than pure g-C3N4 (96.6%). By control experiment, the enhanced photocatalysis is ascribed to the combination of TiO2 and g-C3N4, which not only produced thin films with greater stability but also formed heterojunctions that can be favorable to charge transfer between these two semiconductors with suitable band structure. This study presents the potential application of photocatalytic film in the wastewater treatment under weak-light situation.

In this study, a series of ecological porous spur-dikes are arranged in an experiment channel to simulate a real field drainage ditch. The inside and outside flow fields of spur-dikes are determined by numerical simulations and experimental methods. An Ammonia-Nitrogen (NH3-N) degradation evaluation model is built to calculate the pollution removal rate by coupling with the inner flow field of the porous spur-dikes. The variations of the total pollutant removal rate in the channel are discussed in terms of different porosities and gap distances between spur-dikes and inlet flow velocities. It is indicated that a reasonable parameter matching of the porosity and the gap distance with the flow velocity of the ditch can bring about a satisfactory purification efficiency with a small delivery quantity of ecological porous materials.

TiO2 films have received increasing attention for the removal of organic pollutants via photocatalysis. To develop a simple and effective method for improving the photodegradation efficiency of pollutants in surface water, we herein examined the preparation of a P25-TiO2 composite film on a cement substrate via a sol-gel method. In this case, Rhodamine B (RhB) was employed as the target organic pollutant. The self-generated TiO2 film and the P25-TiO2 composite film were characterized by X-ray diffraction (XRD), N2 adsorption/desorption measurements, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and diffuse reflectance spectroscopy (DRS). The photodegradation efficiencies of the two films were studied by RhB removal in water under UV (ultraviolet) irradiation. Over 4day exposure, the P25-TiO2 composite film exhibited higher photocatalytic performance than the self-generated TiO2 film. The photodegradation rate indicated that the efficiency of the P25-TiO2 composite film was enhanced by the addition of the rutile phase Degussa P25 powder. As such, cooperation between the anatase TiO2 and rutile P25 nanoparticles was beneficial for separation of the photo-induced electrons and holes. In addition, the influence of P25 doping on the P25-TiO2 composite films was evaluated. We found that up to a certain saturation point, increased doping enhanced the photodegradation ability of the composite film. Thus, we herein demonstrated that the doping of P25 powders is a simple but effective strategy to prepare a P25-TiO2 composite film on a cement substrate, and the resulting film exhibits excellent removal efficiency in the degradation of organic pollutants.