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Porous carbon materials have been widely used for the removal of SO2 from flue gas. The main objective of this work is to clarify the effects of adsorption temperature on SO2 adsorption and desorption energy consumption. Coal-based porous powdered activated coke (PPAC) prepared in the drop-tube reactor was used in this study. The N2 adsorption measurements and Fourier transform infrared spectrometer analysis show that PPAC exhibits a developed pore structure and rich functional groups. The experimental results show that with a decrease in adsorption temperature in the range of 50–150 °C, the adsorption capacity of SO2 increases linearly; meanwhile, the adsorption capacity of H2O increases, resulting in the increase in desorption energy consumption per unit mass of adsorbent. The processes of SO2 and H2O desorption were determined by the temperature-programmed desorption test, and the desorption energies for each species were calculated. Considering the energy consumption per unit of desorption and the total amount of adsorbent, the optimal adsorption temperature yielding the minimum total energy consumption of regeneration is calculated. This study systematically demonstrates the effect of adsorption temperature on the adsorption–desorption process, providing a basis for energy saving and emission reduction in desulfurization system design.

Sorption-enhanced reaction process (SEPR) can produce high yield of hydrogen with in-situ CO2 removal using CaO. A key requirement for the process is the integration of effective Ca-based sorbents into catalytic schemes. In this work, the research progress of Ca-based CO2 sorbents in SEPR is summarized. The positive effects by Ca-based sorbents are analyzed. The methods to improve the reactivity of Ca-based sorbents are discussed. A good prospect of compound materials of catalysts/sorbents in SERP is pointed out, for which the relationship between the performance and structure or reaction condition should be further studied. The optimization of process parameters is critically reviewed to provide recommendations for industrial operation. The comprehensiveness of this work extends to the discussion about the applications of Density Functional Theory study in SERP. Process economics requires the integrated H2 production with by-product conversion, renewable resources utilization, waste recycling and heat coupling optimization for the future research.

To develop a new process of sulfur recovery for activated coke desulfurization, reduction of sulfur dioxide by activated coke and pyrolysis gas from powder coke fast preparation system was studied experimentally and theoretically. The distribution of gas products in the experiment was measured by GC-MS analyzer and refinery gas analyzer, while the thermodynamic equilibrium data was calculated by the Factsage software. The activated coke presented great catalytic performance for SO2 reduction by CO and H2. The reactivity of CO reducing SO2 was higher than that of H2, and the two gaseous reducing agents were independent of each other during the reaction process. The effect of CO2 on SO2 reduction was slight, while the participation of H2O resulted in a significant decrease in S yield. The unsteady state experiment shows that the catalytic ability of activated coke did not affect by reaction between carbon and SO2, CO2 or H2O.

Rational design and synthesis of transition metal sulfide complex nanostructures are significant for achieving desired materials properties for a variety of applications. Herein, we synthesized nickel sulfide (NiS) nanostructures using laser irradiation in an aqueous solution and under the ambient condition. Crystalline nanostructures with high phase-purity were achieved without further calcination. Other transition metal sulfides, such as CuS and ZnS, were also successfully synthesized using the laser irradiation approach, suggesting the practical application of this method. The hydrogen evolution reaction (HER) measurements show the NiS nanostructures synthesized for 4h (NiS-4h) not only exhibited competitive overpotential (−159 mV vs. RHE at 10 A/g), lower Tafel slope (218 mV/dec) but also delivered long-term stability (14 A/g at −250 mV vs. RHE for 12h). Moreover, the NiS-4h functioned as the electrode for supercapacitor with excellent specific capacitance (3761 F/g at 10 mV/s), reversibility and rate capability (1152 F/g at 100 mV/s). These superb electrochemical performances are attributed to the remarkable value of electrochemically active surface area (ECSA) and synergistic effect of Ni3+OOH for HER electrocatalytic activities, while the co-existence of Ni2+ and Ni3+ facilitates the rich redox reactions of NiS for supercapacitor.

Microwave-assisted methane reforming with carbon dioxide was dealt with in this work, using a Fe-rich biomass-derived char by one-step preparation. The main factors on the reforming reaction and stability of this catalyst were evaluated, together with a series of characterization on the produced gas and the used char. The char obtained from biomass pyrolysis with Fe2O3 addition of 10% exhibited the best performance on dry reforming reaction. A target CH4 conversion of 95% over this char was realized at 800 °C. Moreover, H2/CO ratio achieved with this char was prone to approach the stoichiometric value. Compared to CO2 conversion, CH4 conversion was more promoted with the increase of CO2/CH4 ratio. The variation of CO2/CH4 ratio also leaded to a noticeable changes on H2/CO ratio. More importantly, the selected char presented a satisfied stability, evidenced by the total decrease of 4.8% for CH4 conversion and 3.1% for CO2 conversion in the test of 160 min. This was contributed to a depressed in-situ carbon consumption and a moderate deterioration of porous structure. Gaseous products obtained with the appropriate char in a long run had a syngas content of 88.79% and H2/CO ratio of 0.92 on average.

Using a modified dynamic Monte Carlo renormalization group method, the two- dimensional kinetic Ising model is studied, and the dynamic critical exponent is obtained. The critical temperature of phase transition can be obtained by the renormalization method for the correlation function. In the method we used, the correlation function is replaced with the absolute value of the magnetization, and it is found that the evolution of the absolute value of the magnetization over time satisfies the power-law form. It is found that the value of the dynamic critical exponent tends to be a stable value in the form of a power-law function as the scale of the system increases. The dynamic critical exponent obtained is z ≃ 2 . 15 . When the modified dynamic Monte Carlo renormalization group method is applied to the two-dimensional Glauber model, the obtained dynamic critical exponent is z ≃ 2 . 25 .

Contrary to conventional methane dry reforming on metallic catalyst using electric heating, dry reforming catalyzed by biomass-derived char with microwave heating was studied in this work. The results showed bio-char catalytic activity could be affected by raw material for char preparation, since it was greatly connected to the remained metal after char preparation. As a whole, cotton stalk char presented better activity than others. Bio-char with a particle size in 0.25–0.83 mm was suitable for being served as the catalyst. Supporting an appropriate additive on bio-char, particularly for Ni, was effective to improve bio-char catalytic ability. Original bio-char could only maintain its catalytic effect at an acceptable level in 70 min, due to an unavoidable carbon gasification reaction. Nevertheless, carbon gasification meanwhile generated part of CO production and it was a contributor to total syngas production. When applying original bio-char for the reforming reaction, the contribution of char-derived CO production to total syngas production was finally up to 10.2%. Deposited bio-char obtained from methane decomposition could be self-regenerated, when further using for dry reforming. No matter original bio-char or deposited bio-char was adopted, a noticeable decrease of H2/CO ratio passed through the test. For example, the ratio achieved on original bio-char reduced from 0.88 to 0.71. Through carbon balance and direct weight measurement, it was obtained a loss by 8.3% was occurred on original bio-char after the test.

Li-ion batteries play a significant role in portable electronic devices in the running world. However, the limited energy density still needs to be improved for the growing future. Hence, we developed a photocathode nanocomposite material composed of Cadmium Selenide/Zinc Sulfide Quantum Dots with Carbon nanotube (CdSe/ZnS QD@CNT) for an efficient and tunable performance of the photoelectrochemical Li–O2 battery system to overcome the key issue of overpotential. The QD and CNT networks can provide efficient transportation paths of the electron–hole pairs and the O2 gas and lithium ions, respectively. The charging voltage of the photoelectrode is 2.65–4.0 V; therefore, decreased overpotential was due to efficient oxidation of Li2O2 by photoexcited electron–hole pairs by using QDs, resulting in a long-term operational stability over 100 cycles. On the basis of the advantages, the QDs exhibit efficient potential in Li–O2 batteries.

In this study we investigated the effect of the Li-excess on electrochemical properties of LixNi0.6Co0.2Mn0.2O2 cathode materials, which was obtained by sintering Ni0.6Co0.2Mn0.2(OH)2 with a various amounts of LiOH (samples with Li-excesses of 5, 10, 20, and 25 mol% are denoted herein as NCM-5, NCM-10, NCM-20, and NCM-25, respectively). The LixNi0.6Co0.2Mn0.2O2 samples retained their excellent crystalline ordering in the rhombohedral layered structure, with the space group R3-m. When the Li-excess increased, Rietveld refinement revealed that cation mixing occurred, the lattice parameters decreased, the transition metal slab thickness increased, and the inter-slab Li space thickness decreased. Nevertheless, an appropriate degree of cation mixing could retain the structural stability and improve the rate capability of the electrodes. It was found that the sample containing the 20 mol% Li-excess (NCM-20) achieved the best cyclic stability, with a capacity retention of 90% at a current rate of 1C/1C for 200 cycles between 2.8 and 4.5 V at room temperature. In situ X-ray diffraction confirmed the greater stability of the crystal phase and physical structure of NCM-20 upon initial cycling. In operando microcalorimetry revealed that the thermal stability of NCM-20 was greater than that of the other cathode materials; it exhibited markedly less heat-generated flux and prevented thermal runaway.

Porous carbon materials have emerged as a new technology with tremendous potential as energy-saving and environmentally friendly pathways for SO2 removal due to its advantages, which include recyclability and a high adsorption capacity. However, the degradation of the performance of adsorbents using thermal regeneration has become a key issue limiting the scaling-up of this new technology. The main purpose of this study is to clarify the effect of the regeneration temperature on the physicochemical properties of activated coke and secondary SO2 removal performance, as well as explore the mechanism by which the circulating adsorbent is deactivated. Using powdered activated coke (PAC) prepared from coal. Experimental results show that adsorbed SO2 desorbs at temperatures between 200 and 500 ℃, while both excess CO2 and CO are released over a wide temperature range owing to the regeneration reaction and decomposition of newly formed oxygen-containing functional groups. The physicochemical properties of PAC are significantly affected by the regeneration temperature. As this temperature rises, the adsorbed sulfuric acid in the pores evaporates and the functional groups decompose, producing several micropores and a large specific surface area. Moreover, the SO2 adsorption–desorption process increases the number of C–O groups such that the active adsorption sites are occupied and SO2 adsorption is prevented. The C-O groups decompose to produce CO2 when exposed to even higher temperatures. The secondary SO2 adsorption experiment demonstrated that the ability of the adsorbent to perform desulfurization could be recovered completely by controlling the regeneration temperature.

To develop a new process for reducing SO2 to elemental sulfur, the reduction of SO2 with carbon materials heated by electrical and microwave were investigated on a fixed bed experimental system. The effects of carbon species, temperature, SO2 concentration and C/SO2 molar ratio on SO2 reduction were studied. The results showed that coconut shell activated carbon has the best reduction effect among the six carbon materials. With the increase of reaction temperature, the XSO2 gradually increased. However, the YS rapidly decreased at 800°C and reached a minimum value of only 55 % at 900℃. The XSO2 increased with the increase of C/S mole ratio, but the YS showed a different trend according to the different reaction temperature. By comparing the effects of microwave heating and electrical heating on the reduction of SO2, the much lower temperature was required to obtain the same XSO2 under microwave heating than that under electrical heating. Also for the SS, the results obtained under microwave heating were higher than that of electrical heating. When the reaction temperature was 950℃, XSO2 was about 98 % under both heating modes. However, YS under microwave heating was 95 %, while YS under electrical heating was only 85 %.

A graphene/silicon (Si) multilayer sandwich structures are fabricated using electron beam (EB) deposition without air exposure. The graphene and Si thin films are formed on Cu current correctors through a continuous process in high-vacuum EB chamber. Synthesized graphene should be suggested to the stacked multiple layer from Raman analysis. The fabricated multilayer films are used as anodes. In the beginning, the half-cell, which used a seven-layer of each thickness 50-nm graphene and Si film, exhibits good specific capacity retention over 1000 mA h g−1 after 30 charge/discharge cycles. The capacity value changed with the number of graphene and Si layers. In this study, the number of layers that exhibited optimal properties is seven. Morphological investigation showed a fine layer-by-layer structure. The relationship between different thicknesses of graphene and Si is investigated at 7 L. A 100-nm thickness exhibited optimal properties. Finally, the optimal 7 L and 100-nm thick graphene/Si exhibited high discharge capacitance >1600 mA h g−1 at a current density of 100 mA g−1 after 30 cycles. Initial coulombic and reversible efficiencies exceed 84%. The capacity retention (30th/1st discharge value) at 100 nm and 7 L exceeds 90%. Finally, the soft package battery is assembled by combining the fabricated graphene and Si electrode as anode, LiCoO2 as cathode, separator and liquid electrolyte. It can be used for commercial light-emitting diode (LED) lighting even under bending status.

This study aimed to characterize the immunopotentiating effects and immune receptors for Coriolus versicolor mushroom polysaccharides (CVP), a Chinese medicinal fungus that exerts anti-tumor activities by enhancing host immunity. Proliferation assays were used to determine whether CVP could activate splenocytes. Flow cytometry analysis and IgM and IgG detection were used to characterize CVP-binding cells. Immune receptors were analyzed in immunoprecipitation and western blot assays. The downstream signaling pathways were identified by western blotting or immunostaining. CVP significantly stimulated the proliferation of mouse splenocytes. Fluorescence-labeled CVP (fl-CVP) selectively stained mouse B cells, but not T cells. CVP induced the production of IgM and IgG1 with or without exogenous IL-4. Membrane Ig (B cell antigen-receptor, BCR) was identified as a CVP-binding protein in immunoprecipitation and western blot experiments. CVP-induced B cell proliferation could be significantly inhibited by anti-mouse immunoglobulin (Ig) blocking antibody (Fab) or in cells from TLR4-mutant mice (C3H/HeJ). Phosphorylation of ERK-1/2 and p38 MAPK were clearly increased in a time-dependent manner, as was the nuclear translocation of the cytosolic NF-κB p65 subunit after CVP stimulation. Together, we demonstrate that CVP can bind and induce B cell activation using membrane Ig and TLR-4 as potential immune receptors. CVP activates mouse B cells through the MAPK and NF-κB signaling pathways.

This study proposes an ensemble-based model (EBM) for the two-class imbalanced classification problem by joining together the support vector machine (SVM), multiple feature selection combination, back-propagation neural network (BPNN) ensemble, and rough set theory (RST). To improve the significance of the rare and specific region belonging to the minority class in the decision region, we take the SVM as a pre-processor to balance the training dataset and use multiple feature selection combination grounded on ensemble learning in order to determine the most representative features from the re-sized dataset. The representative features are then fed into the BPNN ensemble to construct an effective financial pre-warning mechanism. Lacking comprehensibility and readability is one of the fatal weaknesses of an ensemble classifier and it impedes its real-life application. Thus, the study executes RST to extract knowledge from the BPNN ensemble for decision makers to make suitable judgments. Decision makers can take the decision rules as a roadmap to modify a firm's capital structure so as to survive in an extremely turbulent financial market. Empirical results reveal that the introduced EBM's prediction accuracy is very promising in financial risk mining, relative to other detection approaches in this study.

Objectives: To determine the effect of self-talk on softball throwing performance. Additionally, two moderators, nature of self-talk and type of motor task, as well as a potential mediator of self-efficacy were examined. Design: An experimental, within-subjects, and counterbalanced design. Methods: Forty-two senior high students (mean age = 17.48 ± 0.55) were instructed to use instructional, motivational, and unrelated self-talk with counterbalanced order prior to softball throwing for accuracy and distance tasks. Results: Both instructional and motivational self-talk conditions had better performance than unrelated self-talk on softball throwing accuracy, whereas motivational self-talk had better performance than both instructional and unrelated self-talk in softball throwing for distance. Results for self-efficacy were similar, with self-efficacy for accuracy performance higher in both instructional and motivational self-talk conditions than with unrelated self-talk, while self-efficacy was highest in the motivational self-talk condition and lowest with unrelated self-talk. Significant correlations between self-efficacy and motor performance were also found with both tasks. Conclusion: These findings partially support the task-matching hypothesis, confirm the moderator role of type of self-talk and task type, suggest that self-efficacy has a mediator role, and provide direction for self-talk effectiveness.

As chemotherapy causes severe and harmful drug reactions in most of the colorectal cancer patients, predictive biomarkers for treatment efficacy are needed for these patients. In the present study, we investigated the prevalence of single nucleotide polymorphisms related to genes associated with chemotherapeutic agents, 5-fluorouracil plus oxaliplatin or irinotecan, in 255 colorectal cancer patients in southern Taiwan. EGFR codon 497G>A, GSTP1 codon 105 A>G, XPD codon 751 A>C, DPD IVS14 + 1G>A, ERCC1 codon 118 C>T, and UTG1A1 3156 G>A were amplified by polymerase chain reaction and then sequenced. The prevalence of genotypes EGFR codon 497 A/A, GSTP1 codon 105 G/G, XPD codon 751 C/C, DPD IVS14 + 1 A/A, ERCC1 codon 118 T/T, and UGT1A1 3156 AA was 33.73%, 3.01%, 0.39%, 0%, 2.88%, and 1.18%, respectively. However, the correlation between the results of 5-fluorouracil plus oxaliplatin or irinotecan therapy and the frequencies of these single nucleotide polymorphisms needs further investigation.

The sulfonated graphene nanosheet-supported platinum (s-Pt/GNS) catalyst synthesized via a simple thermal-treatment in the presence of concentrated sulfuric acid was reported in this study. Influence of sulfonation on its structural, surface, morphological and catalytic characteristics of as-prepared s-Pt/GNS was explored using X-ray diffractometer, Raman spectrometry, zeta potential analyzer, scanning and transmission electron microscopes, and cyclic voltammetry. For the oxygen reduction reaction, the current density generated from the s-Pt/GNS at 0.6 V was approximately 32.5 A g � 1 Pt, which was about

Biostabilization can remove considerable amounts of moisture and degradable organic materials from municipal solid waste (MSW), and can therefore be an effective form of pretreatment prior to landfill. The environmental and economic impacts of two combined processes, active stage biostabilization + sanitary landfill (AL), and active and curing stage biostabilization + sanitary landfill (ACL), were compared with sanitary landfill (SL) for MSW with high moisture content. The results indicated that land requirement, leachate generation, and CH(4) emission in the ACL process decreased by 68.6%, 89.1%, and 87.6%, respectively, and the total cost was reduced by 24.1%, compared with SL. This implies that a combined biostabilization and landfill process can be an environmentally friendly and economically feasible alternative to landfill of raw MSW with high moisture content. Sensitivity analysis revealed that treatment capacity and construction costs of biostabilization and the oxidation factor of CH(4) significantly influenced the costs and benefits of the AL and ACL process at an extremely low land price. When the land price was greater than 100 USD m(-2), it became the dominating factor in determining the cost of treatment and disposal, and the total costs of ACL were reduced to less than 40% of those of SL.

In the present study, the Nafion ® -based self-humidifying composite membrane (N-SHCM) with sulfonated carbon nanofiber-supported Pt ( s -Pt/CNF) catalyst, N- s -Pt/CNF, is successfully prepared using the solution-casting method. The scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) images of N- s -Pt/CNF indicate that s -Pt/CNF is well dispersed in the Nafion ® matrix due to the good compatibility between Nafion ® and s -Pt/CNF. Compared with those of the non-sulfonated Pt/CNF-containing N-SHCM, N-Pt/CNF, the properties of N- s -Pt/CNF, including electronic resistivity, ion-exchange capacity (IEC), water uptake, dimensional stability, and catalytic activity, significantly increase. The maximum power density of the proton exchange membrane fuel cell (PEMFC) fabricated with N- s -Pt/CNF operated at 50 °C under dry H 2 /O 2 condition is about 921 mW cm −2 , which is approximately 34% higher than that with N-Pt/CNF.

In the present study, a series of highly efficient single-layer gas diffusion layers (SL-GDLs) was successfully prepared by the addition of a vapor grown carbon nanofiber (VGCF) in the carbon black/poly(tetrafluoroethylene) composite-based SL-GDL through a simple and inexpensive process. The scanning electron micrographs of the as-prepared VGCF-containing SL-GDLs (SL-GDL-CFs) showed that the GDLs had a microporous layer (MPL)-like structure, while the wire-like VGCFs were well dispersed and crossed among the carbon black particles in the SL-GDL matrix. Utilization of the SL-GDL-CFs for MEA fabrication was also done by direct coating with the catalyst layer. Due to the presence of VGCFs, the properties of the SL-GDL-CFs, including electronic resistivity, mechanical characteristic, gas permeability, and water repellency, varied with the VGCF content, with the overall effect beneficial to the performance of the proton exchange membrane fuel cell (PEMFC). The best performances obtained from the PEMFC with VGCFs at 15 wt.% was approximately 63% higher than those without VGCFs, and about 85% as efficient as ELAT GDL, a commercial dual-layer GDL, for both the H2/O2 and H2/air systems.

The high water content of municipal solid waste (MSW) will reduce the efficiency of mechanical sorting, consequently unfavorable for beneficial utilization. In this study, a combined hydrolytic-aerobic biodrying technology was introduced to remove water from MSW. The total water removals were proved to depend on the ventilation frequency and the temporal span in the hydrolytic stage. The ventilation frequency of 6 times/d was preferable in the hydrolytic stage. The hydrolytic span should not be prolonged more than 4 d. At this optimal scenario, the final water content was 50.5% reduced from the initial water content of 72.0%, presenting a high water removal efficiency up to 78.5%. A positive correlation was observed between the organics losses and the water losses in both hydrolytic and aerobic stages (R = 0.944, p < 0.01). The evolutions of extracellular enzyme activities were shown to be consistent with the organics losses.

A series of poly(tetrafluoroethylene)/carbon black composite-based single-layer gas diffusion layers (PTFE/CB-GDLs) for proton exchange membrane fuel cell (PEMFC) was successfully prepared from carbon black and un-sintered PTFE, which included powder resin and colloidal dispersion, by a simple inexpensive method. The scanning electron micrographs of PTFE/CB-GDLs indicated that the PTFE resins were homogeneously dispersed in the carbon black matrix and showed a microporous layer (MPL)-like structure. The as-prepared PTFE/CB-GDLs exhibited good mechanical property, high gas permeability, and sufficient water repellency. The best current density obtained from the PEMFC with the single-layer PTFE/CB-GDL was 1.27 and 0.42 A cm −2 for H 2 /O 2 and H 2 /air system, respectively.

A method for the qualitative and quantitative analysis of volatile organic compounds (VOCs) in the air of class-100 clean rooms at semiconductor fabrication facilities was developed. Air samples from two semiconductor factories were collected each hour on multisorbent tubes (including Carbopack B, Carbopack C, and Carbosieve SIII) with a 24-h automatic active sampling system and analyzed using adsorption/thermal desorption coupled with gas chromatography-mass spectrometry. Experimental parameters, including thermal desorption temperature, desorption time, and cryofocusing temperature, were optimized. The average recoveries and the method detection limits for the target compounds were in the range 94-101% and 0.31-0.89 ppb, respectively, under the conditions of a 1 L sampling volume and 80% relative humidity. VOCs such as acetone, isopropyl alcohol, 2-heptanone, and toluene, which are commonly used in the semiconductor and electronics industries, were detected and accurately quantified with the established method. Temporal variations of the analyte concentrations observed were attributed to the improper use of organic solvents during operation.

A nonlinear Continuum Damage Mechanics model (CDM) is proposed to assess the low cycle fatigue life of a steam turbine rotor, in which the effects of mean stress are taken into account and the damage is accumulated nonlinearly. The model is applied to a 200 MW steam turbine under cold start and sliding parameter stop. The results are compared with those from the linear accumulation theory that is dominant in life assessment of steam turbine rotors at present. The comparison results show that the nonlinear CDM model describes the accumulation and development of damage better than the linear accumulation theory.

Mn-doped zinc oxide (ZnO:Mn) thin films with low resistivity and relatively high transparency were firstly prepared on glass substrate by direct current (DC) magnetron sputtering at room temperature. Influence of film thickness on the properties of ZnO:Mn films was investigated. X-ray diffraction (XRD) and scanning electron microscopy (SEM) show that all the deposited films are polycrystalline with a hexagonal structure and have a preferred orientation along the c -axis perpendicular to the substrate. As the thickness increases from 144 to 479 nm, the crystallite size increases while the electrical resistivity decreases. However, as the thickness increases from 479 to 783 nm, the crystallite size decreases and the electrical resistivity increases. When film thickness is 479 nm, the deposited films have the lowest resistivity of 2.1 × 10 − 4 Ω cm and a relatively high transmittance of above 84% in the visible range.