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Electricity trading among multiple microgrids often involves bounded rationality， manifested by varying preferences for losses， uncertainties， and short to long-term returns. This paper proposes a strategy for electricity trading among multiple microgrids considering bounded rationality， drawing on time preference theory and prospect theory. To maximize the revenue for all microgrids， their operators， taking a leading role， determine transaction prices to incentivize cooperative trading among microgrids. Microgrids， acting as followers， formulate a trading strategy while ensuring the maximization of their prospect values of time preference. A case analysis demonstrates that this strategy allows for the swift determination of transaction prices among microgrids， effectively enhancing overall microgrid revenue and the utilization rate of DG （distributed generation）.

Perfluorooctane sulfonate acid (PFOS) is of great concern as a new contaminant. In this study, CoZMo-POP 2 fugacity model was used to simulate and calculate emission, fate distribution, and transfer processes of PFOS, N-EtFOSA, N-MeFOSA, N-EtFOSE and N-MeFOSE in Yangtze River Delta during 1988-2022. The results showed that cumulative emissions of PFOS, N-EtFOSA, N-MeFOSA, N-EtFOSE and N-MeFOSE in the study area were about 26 t, 2.5 t, 0.16 t, 7.8 t and 5.9 t, respectively. The model reliability was verified by fact that residuals of modeled and measured concentrations of PFOS in soil, freshwater, and sediment were within 1 log unit. According to the result of sensitivity analysis, temperature and partitioning coefficients were key parameters affecting pollutant concentrations. When environmental system reached equilibrium, the largest sink of PFOS was coastal water, accounting for approximately 79% of total amount remaining in the system. The transfer from fresh water to estuarine water and estuarine water to coastal water were the main PFOS transfer routes between media, accounting for 53% of total transfer. Flow to the outside is most important output pathway for PFOS. The largest sink of N-EtFOSA, N-MeFOSA, N-EtFOSE and N-MeFOSE were soilaccounting for approximately 99%, 98%, 91% and 97% of total amount remaining in the system, respectively. Degradation was the main output pathway for N-EtFOSA, N-MeFOSA, N-EtFOSE and N-MeFOSE. This study simulated the transfer and fate of PFOS and PreFOS in the environmental multimedia of Yangtze River Delta, which could provide a scientific basis for its pollution control and ecological risk assessment. [ABSTRACT FROM AUTHOR]

Bio-ethanol reforming for hydrogen production, using renewable raw materials and adopting mature and efficient chemical processes, is an important source of green hydrogen supply to achieve the goals of carbon peaking and carbon neutrality. Bio-ethanol is a widely used substitute for fossil fuels. With the continuous progress of cellulosic ethanol technology in recent years, bio-ethanol will gradually break through the constraints of starch-based raw material supply. Based on the industrialization achievements of hydrogen production and bio-ethanol, bio-ethanol reforming can realize a rapid linkage with the existing hydrogen energy industry. However, the existence of a carboncarbon signal bond in ethanol poses new challenges to the development of hydrogen production catalysts, and production technology for the palladium membrane reactor has been significantly improved, creating an opportunity for the miniaturization of equipment and on-line application of bio-ethanol reforming. Bio-ethanol can be supplied through gas stations, and online hydrogen production can avoid the potential safety hazards of hydrogen storage and transportation. Bio-ethanol reforming for online hydrogen production is expected to achieve a seamless replacement of fuel vehicles in the process of industrialization, which has broad market prospects and great strategic significance. [ABSTRACT FROM AUTHOR]

Ethanol plays an important role in the national economy, and is widely used in the raw materials of food, medicine, and the chemical industry. In recent years, with the challenge facing the world's energy security, more and more attention has been devoted to the conversion of biomass into fuel ethanol. Ethanol is considered to be a renewable and clean fuel, which can be an alternative to fossil fuels. So far, compared with other ethanol production methods, the fermentation method to produce ethanol has so many advantages, such as green environmental protection and low cost, that attracts lots of researchers' attention. There are many influence factors in the fermentation process, which make the fermentation process so complicated that it is hard to be controlled. The variation of the ethanol concentration with different fermentation times is directly related to the fermentation results. How to get higher ethanol concentration by a fermentation method has become the hot and difficult issue of the fermentation field. The research of ethanol fermentation kinetic is beneficial for understanding the fermentation process. It provides a theoretical basis for the amplification and optimization of fermentation industry. A bacteria growth dynamics model based on a Logistic equation can better describe the cell growth and inhibition; however, because the parameters and the integral constant of the model equation have no obvious biological significance, its application is limited. To establish a practical product kinetic model of ethanol fermentation, in this article, a reparameterized Logistic model was applied to correlate the ethanol concentration and time in the fermentation process, which was obtained by the analogy of the yeast growth. That is, an explicit function of ethanol concentration is given, which can combine biology and chemical engineering. As there was no yeast concentration in the model, the model was simplified so much and the parameters of it have an immediate physical interpretation that can be conveniently applied in industry. Through the research on glucose and corn starch as the raw material for ethanol fermentation, we studied the variation of ethanol concentration, total sugar concentration with time under the condition of different substrate quality, and the ratio of material to water. Then the experimental data were correlated by the reparameterized Logistic model in ethanol fermentation with glucose and corn starch. The model parameters and the consistency were good between the model and the experiments, the degree of fitting R2, was greater than 0.97. The results showed that the model can be used to represent the kinetics behavior of ethanol concentration in fermentation, which has the potential to predict ethanol concentration in industrial fermentation. [ABSTRACT FROM AUTHOR]

Objective To explore a simple but novel method of strengthening gypsum material by cyanoacrylate infiltration. To evaluate the influence of cyanoacrylate on the mechanical properties of dental gypsum models. Methods Gypsum specimens were polished to the dimension of 35 mm×4 mm×4 mm. Butyl-cyanoacrylate was diluted with chloroform at different concentrations, namely 20% and 30% cyanoacrylate. Gypsum specimens were infiltrated by diluting one component of cyanoacrylate at different concentrations for 8 h and then dried for analysis. The changes in elastic modulus, fracture toughness, compressive strength, biaxial strength, brinell hardness were measured. The data were analyzed using software OriginPro 8. Results The viscosity measurements indicated that diluted cyanoacrylate were Newtonian fluids and the viscosity increased slightly within the 48 hours of preparation but still similar as water at room temperature, which could be used to infiltrating gypsum. The gypsum infiltrated with cyanoacrylate exhibited good physicochemical properties. The biaxial strength, fracture toughness, compressive strength and brinell hardness of the gypsum were improved by 39%, 30%, 63% and 18%, respectively. Conclusion Cyanoacrylate can significantly improve the strength of gypsum model which indicates the potential clinical application. [ABSTRACT FROM AUTHOR]

In order to evaluate the distributions and concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) in aerosol, PM2.5 samples were collected concurrently at five sites in January 2014 in Hangzhou. The analytes were analyzed with isotope dilution and high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) based on US EPA 1613B method and US EPA 1668B method. The results showed that the mass concentrations of PM2.5 were in the range of 85-168 μg/m3, which were much higher than the national quality standard. The values suggested that the PM2.5 pollution was relatively serious in Hangzhou City, yet it has been improved when compared with the results of 2004. The toxic equivalent quantities (TEQs) of PCDD/Fs in PM2.5 were in the range of 0.277-0.488 pg I-TEQ/m3, which were much higher than the results in 2004. Octachlorodibenzo-p-dioxin (OCDD) accounted for a large proportion to the total concentrations in PCDD/Fs, while 2,3,4,7,8-pentachlorodibenzofurans (2,3,4,7,8-PeC- DF) contributed the highest to the TEQ. The values of PCBs and dioxin-like PCBs (DL-PCBs) varied from 2.9-8.1 pg/m3 and 2.6-6.1 fg WHO-TEQ/m3, respectively. PCB-28 was the most abundant contributor to the concentrations of PCBs, while PCB-126 contributed the highest to the TEQ of DL-PCBs. Gas-particle distributions of PCDD/Fs and PCBs shows that PCDD/Fs were mainly distributed in the particle phase, but PCBs were preferably adsorbed in the gas phase.

Objective: To explore a simple but novel method of strengthening gypsum material by cyanoacrylate infiltration. To evaluate the influence of cyanoacrylate on the mechanical properties of dental gypsum models., Methods: Gypsum specimens were polished to the dimension of 35 mmx4 mmx4 mm. Butyl-cyanoacrylate was diluted with chloroform at different concentrations, namely 20% and 30% cyanoacrylate. Gypsum specimens were infiltrated by diluting one component of cyanoacrylate at different concentrations for 8 h and then dried for analysis. The changes in elastic modulus, fracture toughness, compressive strength, biaxial strength, brinell hardness were measured. The data were analyzed using software OriginPro 8., Results: The viscosity measurements indicated that diluted cyanoacrylate were Newtonian fluids and the viscosity increased slightly within the 48 hours of preparation but still similar as water at room temperature, which could be used to infiltrating gypsum. The gypsum infiltrated with cyanoacrylate exhibited good physicochemical properties. The biaxial strength, fracture toughness, compressive strength and brinell hardness of the gypsum were improved by 39%, 30%, 63% and 18%, respectively., Conclusion: Cyanoacrylate can significantly improve the strength of gypsum model which indicates the potential clinical application.

Objective: To investigate the clinical therapeutic results of allograft tendon for anatomical reconstruction of medial patellofemoral ligament (MPFL) in patellar dislocations., Methods: From September 2005 to June 2008, 20 patients with patellar dislocation underwent MPFL reconstructions. There were 4 males and 16 females, aged 13 to 31 years (19 years on average). Patellar dislocations occurred in 7 left and 13 right knees, including 6 cases of acute dislocation and 14 cases of recurrent dislocation. The disease course was 1 day to 2 years. The frequency of dislocation was 1-6 (4 on average). Affected knee joint showed pain, swelling and patellar instability; the range of action for patella obviously increased. The X-ray films showed patellar dislocation or medial margin avulsion fracture. The preoperative Q angle was (15 +/- 3) degrees, the congruence angle was (10 +/- 11) degrees. Reconstruction was performed via allograft tendon. Allograft tendon was anchored to the superomedial pole of the patella by two bone anchors, and the other end was fixed at the natural MPFL insertion site near the medial femoral condyle with an interference screw in a bone tunnel. All patients were evaluated postoperatively; Kujala patellofemoral scores, objective knee function, complications, and reoperations were assessed., Results: Primary healing was achieved in 18 cases and secondary healing in 2 cases. No infection or necrosis and absorption of grafts was observed. All patients were followed up for an average of 25.6 months (range, 6-34 months) postoperatively. At last follow-up, other patients had no pain, swelling and patellar instability except 1 case; neither patella redislocation nor fracture occurred. The X-ray films showed good position of anchors and tunnel 6 months after operation, and the congruence angle was (3 +/- 8) degrees, showed statistically significant difference when compared with preoperation (P < 0.05). The postoperative Q angle was (15 +/- 2) degrees, the Kujala knee function score improved significantly from 60.8 +/- 7.2 to 83.4 +/- 8.0 at last follow-up, showing statistically significant difference (P < 0.05). According to Insall et al. for function, the results were excellent in 12 cases, good in 6 cases, and fair in 2 cases, the excellent and good rate was 90%., Conclusion: MPFL reconstruction improves clinical symptoms. Anatomical MPFL reconstruction is effective for patellar dislocation, and it offer good recovery of the pre-morbid patella mechanics. There would be little bone loss when tendon is fixed by anchors, and there would be less patellar fracture than bone tunnel technique. The bone anchors also provide firm fixation. Allograft can avoid the graft harvest site morbidity, but it increases the cost of the surgery.

Objective: To study the chemical constituents in the tubers of Dioscorea bulbifera., Method: Compounds were isolated and purified with silica gel, ODS and Sephadex LH-20 column chromatography, their structures were determined by using spectroscopic methods including MS and NMR., Result: Fourteen compounds were isolated and identified as stigmasterol (1), mono-arachidin (2), 1,7-bis-(4-hydroxyphenyl)-1E,4E,6E-heptatrien-3-one (3), behenic acid (4), demethyl batatasin IV (5), 2,3'-di-hydroxy-4',5'-dimethoxybibenzyl (6), diosbulbin B (7), diosbulbin D (8), docosyl ferulate (9), 7-bis-(4-hydroxyphenyl) -4E, 6E-heptadien-3-one (10), 5,3,4-trihydroxy-3,7-dimethoxyflavone (11), tristin(12), protocatechuic acid (13), adenosine (14)., Conclusion: Compounds 24, 6, 9, 10, 12, 14 were isolated from the genus Dioscorea for the first time.

The M2 ion channel protein is an important target against influenza A virus. In this study, H5N1 influenza A virus M2 ion channel (H5M2) gene was cloned into pcDNA4 vector. The HEK293 stable cell line expressing H5M2 was successfully established. The expression of H5M2 ion channel protein was induced only by tetracycline and confirmed by imuunofluorescence and Western blot. The ion channel activity of H5M2 was confirmed by whole cell patch-clamp recording. Fifty micromol per liter amantadine blocked the H5M2 channel conductance completely in HEK293 cells. This stable cell line may provide a model for screening inhibitors of M2 ion channel.