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Photocatalytic fixation of nitrogen to ammonia (NH3) is green but low-efficiency technology due to the high recombination of photo-generated carriers and poor light absorption of photocatalysts. Generally, the adsorption capacity for N2 and the band position of TiO2 are responsible for bandgap, light-adsorption, and the separation of photocarriers. Therefore, they play crucial roles to improve catalytic activity. Herein, N-doping TiO2 hollow microspheres (NTO-0.5) with oxygen vacancies were synthesized via a hydrothermal method using phenolic resin microsphere as a template. The obtained NTO-0.5 achieves an impressive ammonia yield of 80.09 μmol gcat-1 h-1. Oxygen vacancies of NTO-0.5 were confirmed by ESR, Raman, XPS, Zeta potential, and H2O2 treatment for reducing oxygen vacancies. The ammonia yield of NTO-0.5 decreases to 34.78 μmol gcat-1 h-1 after reducing oxygen vacancies by H2O2 treatment, which demonstrates the importance of oxygen vacancies. The oxygen vacancies narrow the bandgap from 3.18 eV to 2.83 eV and impede the recombination of photo-generated carriers. The hollow microspheres structure is conducive to light absorption and utilization. Therefore, the synergistic effect between the oxygen vacancies and the hollow microspheres structure boosts the efficiency of photocatalytic nitrogen fixation. After four cycles, the ammonia production yield still maintains at 76.52 μmol gcat-1 h-1, meaning high stability. This work provides a new insight into the construction of catalysts with oxygen vacancies to enhance photocatalytic nitrogen fixation performance.

When applying an additional coating method to fabricate micro-nano hierarchical structure required for superhydrophobic function on glass surface, the hierarchical structure does generally not have good abrasion resistance, due to the weak adhesion between coating and glass surface. However, glass itself is a material with good abrasion resistance. A micro-nano hierarchical structure with honeycomb-shaped micro-armor protection on glass surface by a two-step hydrothermal corrosion method has been constructed: the first step of hydrothermal corrosion in water to construct micro-armor structure, and the second step of hydrothermal corrosion in sodium citrate aqueous solution to fabricate micro-nano hierarchical structure. The advantages of this new method are: the treatment process is simple, and there is no need to apply additional coatings. The micro-nano hierarchical structure constructed on glass surface by this method has a great abrasion resistance. After 1,000 cycles of abrasion under harsh conditions, the nano-structure on glass surface can still be remained intact. It provides a new method for fabricating abrasion-resistant micro-nano hierarchical structure on glass surface, as well as a new approach to the preparation of abrasion-resistant superhydrophobic glass.

Salicylic acid (SA) plays a pivotal role in delaying fruit ripening and senescence. However, little is known about its underlying mechanism of action. In this study, RNA sequencing was conducted to analyze and compare the transcriptome profiles of SA-treated and control pear fruits. We found a total of 159 and 419 genes differentially expressed between the SA-treated and control pear fruits after 12 and 24 h of treatment, respectively. Among these differentially expressed genes (DEGs), 125 genes were continuously differentially expressed at both treatment times, and they were identified as candidate genes that might be associated with SA-regulated fruit ripening and senescence. Bioinformatics analysis results showed that 125 DEGs were mainly associated with plant hormone biosynthesis and metabolism, cell wall metabolism and modification, antioxidant systems, and senescence-associated transcription factors. Additionally, the expression of several candidate DEGs in ripening and senescent pear fruits after SA treatments were further validated by quantitative real-time PCR (qRT-PCR). This study provides valuable information and enhances the understanding of the comprehensive mechanisms of SA-meditated pear fruit ripening and senescence.

Background Radiotherapy is a viable treatment option for patients with unresectable hepatocellular carcinoma (HCC). However, radiation resistance is an issue that needs to be addressed. In this context, cumulative evidence supports the functional roles of a variety of RNA or proteins in radioresistance, and suggests that the modulation of their expression may constitute a novel radiosensitization approach. Here, we investigated the ability of collectrin (CLTRN) to enhance the radiosensitivity in HCC patients for the first time. Methods Transcriptome sequencing technology (RNA-seq technology) was used to analyze the transcription-level changes in the genes from the HepG2 cells before and after X-ray irradiation. Combining the results with the HCC tissue RNA-seq data, we determined the ultimate target gene through bioinformatics analysis and cellular verification. A series of cellular and molecular biology techniques were applied in vitro and in vivo to confirm whether CLTRN can enhance radiosensitivity in HCC cells. Subsequently, the downstream action mechanism, the upstream transcription factor, and the interaction proteins of CLTRN were determined. Results First, we confirmed the association between CLTRN and radiosensitivity. We observed that CLTRN overexpression led to a significant reduction in the proliferation, migration, and invasion potential of X-ray-irradiated HCC cells, whereas no observable effect was exerted on cell cycle and apoptosis. The same results were observed in nude mice in vivo. Investigation of the gene regulatory mechanism revealed that the genes analyzed at transcriptome level after CLTRN overexpression were mostly enriched in the glutathione metabolic pathway. As glutathione metabolism forms a vital link in ferroptosis, we surmised that CLTRN is associated with ferroptosis. This was confirmed through the detection of cellular iron, ROS level determination, transmission electron microscopy, and monitoring of ferroptosis-related protein indicators. Lastly, we investigated whether nuclear respiratory factor 1 (NRF1) is the upstream transcription factor of CLTRN, and whether dihydrolipoamide dehydrogenase (DLD) and members of the RAS oncogene family (RAN) are its interacting proteins. Conclusion Our results indicate that CLTRN is a vital regulator of radiation sensitivity and could serve as a novel therapeutic target or prognostic marker in HCC treatment.

In the crowdsourcing task allocation scheme, there is an emerging and realistic co-opetition phenomenon. To availably solve the crowdsourcing task allocation problem with co-opetition, this paper designs a two-stage co-opetition model by constructing novel three-way decision (TWD), including a competition-optimization model and a negotiation-cooperation model. Unlike the other studies, the two-stage co-opetition model with TWD can not only protect the profits of the task candidates, but also optimize the overall benefits. Specifically speaking, in the competition-optimization model, we construct an optimization model based on the data envelopment analysis (DEA) method in advance, which maximizes the personal benefit. By integrating information system and the loss function matrix, we consider the linkage of evaluation information and risk information and then improve the original TWD to make an initial allocation. In the negotiation-cooperation model, considering that the relationship among the candidates may influence the task performance, the fuzzy measure is introduced to describe a broader partnership. Meanwhile, we also design two different schemes to coordinate and optimize the best task allocations based on the initial allocation. In order to choose the best scheme, the selection strategy between schemes is further investigated under the guidance of the utility and the loss. Finally, we give an example of a medical supply chain crowdsourcing problem to illustrate and verify our proposed approach.

Cost-competitive production of lignocellulosic H2 using biological methods is limited by energy-intensive pretreatments and expensive cellulase hydrolysis. Here we report stable two-stage fermentation to convert unpretreated energy sorghum without added cellulase to H2, where Clostridium thermocellum was fed semi-continuously with 20 g/L sorghum in the first stage and then Rhodobacter sphaeroides consumed the effluent wastes in the second stage to achieve residence times (RTs) of 60, 48, and 24 h. Glutamic acid was the preferred nitrogen source for coordinating the two-stage, two-organism fermentation. 25.0 ± 1.1 mL-H2/day in consolidated bioprocessing stage and 133.0 ± 1.5 mL-H2/day in photofermentation stage were obtained for 200 mL cultures at RT 48 h. Propionate is the main product accumulated, with cellobiose, xylose, arabinose, formate, acetate and ethanol also observed in the effluent wastes, which were degraded effectively by Rhodobacter sphaeroides with COD removal of 72.6%. These results provide references for developing low-cost H2 production from lignocellulose.

A bacterium was newly isolated from cow dung, and identified as Enterococcus faecium YA002 by 16S rRNA gene sequence analyzing. It showed high H2 production performance in dark fermentation with xylose as substrate, the fermentative conditions including xylose concentration, ratio of nitrogen source to carbon source in mass (N/C ratio), temperature, and initial pH were optimized by response surface methodology (RSM) with a Box-Behnken design (BBD). After regression analyzing, it could be found that H2 production was well fitted by a quadratic polynomial equation, and significantly affected by the four studied factors. The optimal conditions were xylose concentration of 22.69 g/L, N/C ratio of 0.127, temperature of 37.2 °C, and initial pH of 8.0, and the experimental H2 production under the conditions was 2918.91 ± 125.49 mL/L, which was 97.91% of the predicted H2 production. The results indicated that Enterococcus faecium YA002 was an ideal inoculum for dark fermentative H2 production from xylose, and the conditions for the H2 production were successfully optimized by response surface methodology.

Ultra-deep major gas fields are typically characterized by high and ultra-high pressure, tight matrix and developed fractures, so the reserve estimation is of higher uncertainty. In order to accurately estimate the reserves of this type of gas reservoir, this paper analyzed the correlation between the effective rock compressibility and the cumulative effective rock compressibility based on the material balance equation of high and ultra-high pressure gas reservoirs, and accordingly selected the material balance based analysis method suitable for the reserves estimation of high and ultra-high pressure gas reservoirs. Then, the starting calculation conditions of reserve estimation were determined using the non-linear regression method. In addition, a semi-logarithmic type curve matching method was established for the cases where the starting conditions could not be met. Finally, this method was applied to calculate the reserves of three ultra-high pressure gas fields (reservoirs) to verify its reliability. And the following research results were obtained. First, the cumulative effective compressibility of gas reservoir in the material balance equation of high and ultra-high pressure gas reservoir is a key parameter influencing its reserves, and it is the function of original formation pressure and current average formation pressure, but its numerical value can be hardly obtained by core experiments. Second, it is recommended to adopt the nonlinear regression method without compressibility to estimate the reserves of high and ultra-high pressure gas reservoirs. Third, the calculation starting point of reserves by the nonlinear regression method (the starting point of dimensionless apparent formation pressure-cumulative gas production curve deviating from the straight line relationship) cannot be theoretically calculated. The calculation starting point for different dimensionless linear coefficients (ωD) obtained from the statistical results by the graphic method corresponds to the dimensionless apparent pressure depletion degree of 0.06–0.38, and that obtained based on the data statistics of the example gas reservoir falls within this interval. Fourth, when the starting conditions are not satisfied, the semi-logarithmic type curve matching method can be used for reserve estimation. The ratio of the reserves to the apparent geological reserves G/Gapp is a function of ωD.The higher the ωD, the lower the G/Gapp. Fifth, for the high and ultra-high pressure gas reservoirs in the production test stage, the test production time shall be extended as long as possible to improve the reliability of reserve estimation. And for those in the middle and late stages of development, it is necessary to prepare the comprehensive treatment measures on the basis of reserves so as to improve the development effects of gas reservoirs continuously.

Supercritical water gasification technology can realize efficient conversion of biomass, coal and other organics into hydrogen rich gas. But the efficiency of non-catalytic gasification at relative low temperature is not high. Besides, as for catalytic gasification, catalysis mechanism is complex. Thus how to improve efficiency and master the catalysis mechanism is a challenging issue. In this thesis, supercritical water gasification of depolymerizing slag experiments with the catalysis of different kinds of catalysts are conducted and the catalysis mechanism is analyzed. The results indicate that catalyst mechanism of K2CO3 is that it can promote the swelling and hydrolysis of lignocellulose and increase the amounts of phenolic intermediates. Ru/Al2O3 presents some different catalytic properties. It facilitates hydrogenation reaction of hydrolysis products, ring-opening reaction and the cleavage of carbon-carbon bonds then enhances gasification degree and increases gasification efficiency. Moreover, the binary catalyst displays a good synergic effect and the catalytic activity is higher than that of any single catalyst since these two catalysts promote various gasification stages. The gasification efficiency and hydrogen yield increase 13.22 mmol g−1 and 66.46% respectively with the synergic catalyst of K2CO3 and Ru/Al2O3.

Sodalime float (SF) glass is widely used in our societies and industries. Hydrothermal corrosion method is one of the effective ways to prepare a superhydrophobic glass, but there is still lack of knowledge about hydrothermal corrosion behavior and mechanism of SF glass. We have hydrothermally treated SF glass at 180 °C for different time, and tried to reveal the aqueous corrosion process of SF glass. We have characterized the morphologies and chemical compositions of samples, and found that (1) the two sides of SF glass have different corrosion resistances, and (2) a multilayer structural coating with a nanoflake layer (Mg-rich gel layer), a nanowire layer (Ca-rich gel layer), and a porous layer (etched layer) is formed on the air-side of SF glass. Based on the experimental results, we have proposed an aqueous corrosion mechanism of SF glass. The insights of the hydrothermal corrosion behaviors and mechanism provide helpful guidelines to glass surface structural control and functionalization.

This paper explores the state estimation method of lithium-ion battery pack through theoretical analysis and experimental research. Combining the advantages of the empirical models of various electrochemical models, a new type of composite electrochemistry-dual circuit polarization (E-DCP) model is proposed to better reflect the dynamic performance of the power lithium-ion battery under the conditions of meeting its safe and reliable energy supply requirements. Using the multi-innovation least squares (MILS) algorithm to identify the parameters in the E-DCP model online, so that it has the characteristics of high data utilization efficiency and high parameter identification accuracy. The battery charge and discharge efficiency function is introduced to dynamically modify the battery capacity, and the dynamic function is used to improve the Kalman gain in the extended Kalman filter (EKF), a new type of based on dynamic function improvement and combined with actual capacity correction (FC-DEKF) algorithm is applied to the estimation of battery pack operating characteristics, which solves the problem that the traditional EKF algorithm is difficult to estimate errors when the system input change rate is large. The experimental results of urban dynamometer driving schedule (UDDS) and complex charge-discharge cycle test show that the maximum error of terminal voltage does not exceed 0.04V, the accuracy is 99.05%, and the errors of MILS algorithm combined with FC-DEKF algorithm for SOC estimation are all within 1%. The proposed equivalent circuit modeling method and state estimation correction strategy provide a theoretical basis for the reliable application of high-power lithium-ion battery packs.

Supercritical water gasification technology is widely applied to convert organic waste into valuable substances as a clean and efficient method. Biomass gasification in SCW is a complex process and complicated chemical reactions like decomposition and poly-condensation take place, thus, reaction mechanism of real biomass needs to be further investigated. In this paper, experimental study on cornstalk gasification in SCW was conducted at the temperature of 500–800 °C, reaction time of 1–15min and feedstock concentration of 1–9%. The effects of various operating parameters on evolution of gas, liquid and solid products were conducted. It was discovered that pore structure and carbon microspheres appeared successively on the surface of solid residue. Mechanism study showed that the biomass was first depolymerized into monomer and its derivatives, then cracked and poly-condensed into a nuclear to generate carbon microspheres as its concentration reached the critical concentration. As the reaction proceeds, reduction reaction, coke combustion and secondary reaction occurred, thus carbon microspheres decreased. The results indicated that higher reaction temperature, longer reaction time and lower feed concentration were conducive to improving reaction performance of biomass. Finally, it was discovered that carbon gasification efficiency reached 99% at the temperature of 700 °C, reaction time of 15 min and biomass concentration of 3%.

Rapid heating of coal particles in supercritical water (SCW) is the prerequisite for complete gasification, while there is a rapid precipitation of volatiles during this process. If the volatiles cannot be dissolved and diffused in time, side reaction is inclined to occur, especially coking. The solubility of the volatiles in SCW has not yet been studied because the composition is not simple and the corresponding interaction with SCW is complex. In this paper, polycyclic aromatic hydrocarbons (PAHs) were used as the volatile model compound. Molecular dynamics (MD) simulations focused on the dissolution of pure PAHs and PAHs mixtures in SCW were carried out. The investigation results indicated that the dissolution behavior of naphthalene was the most excellent in SCW, while heavy PAHs were sensitive to the thermodynamic state of water molecules. The light PAHs were liable to be dissolved, while heavy PAHs were more likely to be remained in the PAH droplet. Moreover, the increase of temperature and density has a positive impact on the dissolution of PAHs in the supercritical solvent. This work is prospective to provide a theoretical basis for ensuring efficient and complete gasification of coal and restraining side effects for hydrogen production.

Low haze and anti-reflective glass has high potential applications in automobile and optoelectronic fields. Etching is a novel and effective method to fabricate gradient refractive index anti-reflective layer on glass surface. However, the gradient layer on glass surface prepared by the etching method usually characterizes rough porous structure, and the structural defect results in high haze and low abrasion resistance to restrict its applications. In this paper, a hydrothermal etching method has been explored to prepare anti-reflective glass. It has demonstrated to be a new and facile method successfully to tailor the porous nanostructure of gradient refractive index layer and largely decrease the haze of the glass, by adding complex compound in the etching solution. Compared with the etching solution containing NaOH, adding the complex compound of C6H5Na3O7 in the etching solution has the advantage to overcome the defects. The grain diameter of the graded porous anti-reflective film decreases from ~63 nm to ~18 nm, the etched film thickness increases from 0.44 μm to 1.55 μm, the haze decreases drastically from 23.76% to 1.00%, the reflectivity decreases from 5.88% to 1.08% and the abrasion resistance greatly increases. However, when changing the complex compound from C6H5Na3O7 to Na2HPO4, the haze is 23.44% and has no effect on decreasing haze. Structural characterizations show that the grain size in the porous gradient layer can be easily tailored by changing the ion radius of complex anion in the etching solution, and the optical properties can be controlled. The paper provides new insights into the nanostructures and the preparation approach of anti-reflective glass.

In order to quickly and accurately evaluate gas well deliverability, it is necessary to clarify the applicable conditions of the simplified laminar-inertial-turbulent gas well deliverability evaluation method (i.e., pressure-squared method and pressure method). In this regard, this paper analyzes the PVT data, simulation wells and field case wells of typical gas reservoirs in China by reviewing the formal evolution of the flow control equation for the real gases in porous media. Then, the applicable conditions of binomial pressure-squared method and pressure method are discussed. And the following research results were obtained. First, when the pressure is lower than 14 MPa, μZ is basically a constant; and when the pressure is higher than 42 MPa, ρ μ Z is basically a constant. Second, the applicable range of the pressure-squared method can be increased from 14 to 20 MPa. In this case, the relative error of absolute open flow potential calculated using the pressure-squared method is less than 5% compared with the pseudo-pressure method. If the pressure is between 20 and 30 MPa, the relative error of the absolute open flow potential calculated using the pressure-squared method is less than 10%. Third, when the pressure exceeds 80 MPa, the relative error of the absolute open flow potential calculated using the pressure method is less than 10% compared with the pseudo-pressure method. If the pressure-squared method is used in the case of high pressure, the calculated absolute open flow potential is lower and the relative error is close to 25%. Fourth, in the case of low pressure, if the pressure is constant, the higher the temperature is, the smaller the relative error between the pressure-squared method and the pseudo-pressure method is. In the case of high pressure, if the pressure is constant, the higher the temperature is, the greater the relative error between the pressure method and the pseudo-pressure method. In conclusion, it is recommended to adopt the pseudo-pressure method in laminar–inertial-turbulent gas well deliverability analysis. In the case of low pressure (below 30 MPa), the pressure-squared method can be used. In the case of high pressure (above 80 MPa), the pressure method can be applied.

In this study, in order to evaluate the influences of drying methods on the chemical structures and bioactivities of polysaccharides from okra (OPPs), four drying methods, including microwave drying at 400 W, 600 W, and 800 W, freezing drying, hot air drying, and vacuum drying, were applied to dry okra fruits. Six different OPPs were extracted from okra dried by different drying methods. Results showed that physicochemical characteristics and bioactivities of OPPs varied by different drying methods. Noticeable variations in extraction yields, molecular weights, rheological properties, molar ratios of constituent monosaccharides, contents of uronic acids, degrees of esterification, and contents of total phenolics were observed in OPPs obtained by different drying methods. In addition, results showed that OPPs, especially OPP-H and OPP-V obtained by hot air drying and vacuum drying, respectively, exhibited remarkable antioxidant activities (ABTS, DPPH, and nitric oxide radical scavenging activities, and ferric reducing antioxidant powers), strong in vitro binding capacities (fat, cholesterol, and bile acids binding capacities), and obvious inhibitory activities on α-amylase and α-glucosidase. Results suggested that the hot air and vacuum drying techniques could be appropriate drying methods before extraction of OPPs with high bioactivities for applications in the functional food and medicine industries.

Purple non-sulfur bacteria (PNSB) are well known for converting short-chain organic acids to H2, however, a decrease in pH caused by metabolic acids production limited H2 production during the photo-fermentation from glucose. Here we address why volatile fatty acids (VFA) excreted as fermentation products cannot be further degraded by R. sphaeroides that readily use them. We found that the photo-fermentation with pH controlled at 6.9 ± 0.1 resulted in a 90% increase of H2 yield and a 107.6% increase in volume H2 production relative to the pH-uncontrolled culture. Comparative fermentations on glucose at pH 5.8 and pH 7.1 using culture medium supplemented with 50% spent fermentation broth demonstrated that low pH alone is not the limiting factor and compounds present in the supernatants along with pH decrease were the most inhibitory to H2 production. The impact of byproducts VFA on phototrophic H2 production was dependent on both the pH and VFA concentrations; even 7 mM VFA addition totally inhibited H2 production from glucose at pH 5.4. H2 production with pH control for the Δhup strain was not discernibly different from the parent strain, which are all significantly higher than high-performance strains by metabolic engineering. These results demonstrate that pH dependent VFA inhibition can be turned into a driving force for enhanced H2 production from glucose by pH regulation.

Agricultural plastic films and triazole fungicides are widely used in agricultural production process. Exposure to natural environment, agricultural plastic films will degrade into micron plastic particles, which will adsorb pesticide molecules and may affect their toxicity, biological activity and persistence. The long-term coexistence of microplastics (MPs) and triazole fungicides will bring potential harms to the agricultural ecological environment. Therefore, two kinds of triazole fungicides flusilazole (FLU) and epoxiconazole (EPO) were selected as cases and the adsorption behaviors of them on polystyrene and polyethylene were investigated. A series of factors which could affect the adsorption behavior were evaluated. Specifically, the particle size of MPs could affect its adsorption capacity, and the smaller the particle size, the stronger the adsorption capacity. Moreover, with the increase of pH value from 6.0 to 9.0, the adsorption capacity of MPs to target compounds gradually increased. The effect of ionic strength was evaluated by NaCl, and 0.05% of NaCl was beneficial to the adsorption process, while the continuous increase of NaCl concentration inhibited the adsorption. Oxalic acid and humic acid decreased the adsorption capacity of flusilazole on PE by 15.99-32.00% and PS by 35.02-48.67%, respectively. In addition, compared with the single pesticide system, the adsorption capacity of MPs for flusilazole and epoxiconazole in the binary pesticides system decreased by 36.13-37.93% and 44.36-51.35%, respectively, indicating that competitive adsorption occurred between the two pesticides. Meanwhile, the adsorption process was evaluated by adsorption kinetics and adsorption isotherms and were consistent with pseudo-second-order kinetic model and Freundlich isotherm model, respectively. Finally, several characterization analyses were conducted to investigated the adsorption mechanism, and hydrogen, halogen bonding and hydrophobic interaction proved to play an important role. The study on the adsorption behavior and mechanism of pesticide on MPs was the basis of assessing the risk of joint exposure.