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Psidguajones A and B, a pair of dimeric sesquiterpene-based meroterpenoid epimers, have been isolated from the leaves of Psidium guajava for the first time. Their structures were confirmed by comprehensive spectroscopic techniques combined with a comparison of experimental and calculated ECD data.

The investigation of protein folding intermediates is of great significance for exploring the folding mechanism of denatured proteins and improving the folding efficiency of protein. In the present research, by taking some of linear parameters of stoichiometric displacement theory of retention of solute (SDT-R) of hydrophobic interaction chromatography (HIC), a new approach to characterize the intermediate of urea-denatured α-chymotrypsin (α-Chy) was developed. The contact surface region (Z, S), affinity (logI), and the character of interaction force (j) of the α-Chy to the stationary phase of HIC (STHIC) between the intermediate (M) and native (N) states were found to be quite different as urea concentration (Curea) changes. With the changes inCurea, a linear relationship between logI and Z was found to exist only for its N state, rather than for M state, indicating the interaction force between α-Chy in N state to the STHIC to be non-selective, but selective one for its M state. Also, the measured magnitude of both logI andZ in M state is only a fifth of that in N state. All three parameters were employed to distinguish protein in the N state from that in the M state. It would be expected that this result could be employed to distinguish any kind of non-functional protein having correct three-, or four-dimensional molecular structure from their stable M state of any kinds of proteins, and/or other proteins in proteome investigation, separation process of protein, and intensively understanding the intrinsic rule of protein folding in molecular biology.

Methyl-2-(1-methyl-2′-amino-ethane)amino-1-cyclopentenedithiocarbo-xylate was supported on the modified Fe3O4 MNPs. Afterwards, Pd(OAc)2 was immobilized on the modified MNPs and, then, the nanoparticles were analyzed using FT-IR, XRD, EDS, ICP-OSE, SEM, TGA and VSM spectroscopy. The catalytic efficiency of the prepared heterogeneous Pd-NPs was successfully examined in “Heck cross coupling reaction”, involving the reaction of butyl acrylate with various aryl halides in water. The advantages of this strategy include, easy recovery and efficient reusability of the expensive Pd-NPs, obtaining high yields of the butyl cinnamate cross-coupled products, short reaction times, and being performed in water for a wide range of substrates. A novel HcdMeen-Pd(0) complex was synthesized on the surface of modified Fe3O4 MNPs and fully characterized by FT-IR, XRD, EDS, ICP-OSE, SEM, TGA and VSM spectroscopy analysis. The obtained complex was then used for Chemo And Homoselective Heck C–C cross-coupling synthesis of butyl cinnamates with in water as green solvent.

One of the main challenges in multi-chill system issues by considering the uncertainty of cooling demand is total energy consumed and energy buying cost. Therefore, it is necessary to optimize power consumption in these issues. This paper provides a robust optimization method with uncertainty modeling in multi-chiller systems to obtain accurate planning. It should be noted that one of the energy supply sources for multi chiller system is photovoltaic system (in addition to the network). In order to improve cooling demand profile, using demand response program, demand levels are shifted through peak periods of energy consumption to low consumption periods. In this work, the minimization of energy procurement cost of multi-chiller systems from the upstream network is assumed as a target function, taking into account demand response of cooling and uncertainty demand. Also, the effect of cooling demand response on two robust and deterministic strategies has been investigated. Achieved results depict, risk-averse method through robust method is robust against cooling requirement uncertainty, contrasting to risk-neutral method through deterministic approach. In addition, the cost of supplying energy of multi-chiller systems from solar systems is reduced by using the demand response program in both of mentioned methods.

NoSQL database can provide massive, high concurrency, and scalable services for storing different types of data. HBase, a type of NoSQL database, in which columns are grouped into column families, is very suitable for storing semi-structured or unstructured spatial vector data. However, since there are few rules and constraints to be followed for the NoSQL database, the design of storage schema for spatial data based on NoSQL is difficult. In this paper, based on our early work, an improved Z-curve storage schema is proposed for spatial vector data. According to our new schema, row key of a geometric object is the Z-curve code of the spatial grids intersected with the geometric object. Moreover, geometric objects with the same row key are stored in a column family. Our proposed method has two features. First, geometric objects adjacent in the location are adjacent in physical storage. Second, redundant exists in storage for improving query accuracy. In our experiments, we compare the improved Z-curve storage schema with a Quadtree storage schema, an R-tree storage schema, and the previous Z-curve storage schema. Query response time, memory usage, and the query accuracy of spatial query on point and range are used to verify the validity of our proposed method. The experimental results show that the two storage schemas based on Z-curve achieve higher query efficiency than the two storage schemas based on tree-the Quadtree storage schema and the R-tree storage schema. More importantly, the query results of the improved Z-curve schema are completely correct, while the query results of the previous Z-curve schema are not.

Background We demonstrate an innovative approach of automated sleep recording formed on the electroencephalogram (EEG) with one channel. Methods In this study, double-density dual-tree discrete wavelet transformation (DDDTDWT) was used for decomposing the image, and marginal Fisher analysis (MFA) was used for reducing the dimension. A proposed model on unprocessed EEG models was used on monitored training of 5-group sleep phase forecasting. Results Our network includes a 14-row structure, and a 30-s period was extracted as input in order to be categorized which is followed by second and third period prior to the first 30-s period. Another consecutive period for temporal tissue was added which is not required to a signal preprocess and attribute data derivation phase. Our means of evaluating and improving our approach was to use input from the Sleep Heart Health Study (SHHS), which is a large study field aimed at using research from numerous centers and people and which studies the records of specialist-rated polysomnography (PSG). Performance measures could reach the desired level, which is a precision of 0.87 and a Cohen's kappa of 0.81. Conclusions The use of a large, collaborative study of specialist graders can enhance the likelihood of good globalization. Overall, the novel approach learned by our network showcases the models based on each category.

Currently, due to its tremendous availability, the use of municipal solid waste (MSW) as an energy source has received significant attention in China. Moreover, when compared to coal and oi...

PEM fuel cell is an electrochemical system that converts the chemical energy of hydrogen directly into electricity and is widely used as an energy source for ground vehicle applications. This paper...

Asphaltene precipitation is known as one of the challenging problems in petroleum industries which have significant effects on production such as formation damage and wellbore plugging, that consequently impose a serious restriction on production and in turn increases total cost of entire operation. Through decades an extensive research has been performed in order to identify asphaltene molecular structure, its behavior at different condition, and its departure mechanism from oil. One of most critical parameter associated with asphaltene precipitation modeling is flocculated asphaltene weight percentage in oil at given operation condition. In this investigation, to eliminate cost and time related with experimental procedure that concern with determining this critical parameter, a novel hybrid structure of ANN and FIS with the help of Genetic algorithm has been developed, which trained and tested by over 350 experimental data. The constructed network show good performance regarding flocculated weig...

The higher heating value (HHV) is known as one of the energy evaluation parameters for biomass which has wide application in economic aspects investigation of energy sources. In this investigation ...

Bamboo macromolecules were pretreated with bamboo vinegar, which has an antibacterial property, and processed into antibacterial bioboard (ABB) by hot pressing. The ABB was then analyzed by conducting Fourier-transform infrared spectroscopy, thermogravimetric analysis and differential thermal analysis. Results showed that ABB samples had average density of 1.0 g/cm3, which is appropriate for application. The physical and mechanical properties were best for the ABB sample pretreated with bamboo vinegar and hot pressed at 165 °C for 10 min. Fourier-transform infrared spectroscopy revealed that the optimum conditions for hot pressing were a temperature of 165 °C, duration of 10 min, and the addition of bamboo vinegar. Thermogravimetric analysis/differential thermal analysis curves indicated that the thermal degradation of the ABB was less than that of bamboo, revealing that hot pressing increased the thermal stability of ABB samples. Analysis revealed that pretreatment with bamboo vinegar improved the antibacterial property of the ABB. Keywords: Bamboo vinegar, Bamboo macromolecule, Antibacterial bioboard, Fourier-transform infrared spectroscopy, Thermogravimetric analysis/differential thermal analysis

The most important characteristics and limitations of solar energy were reviewed in this study. The analysis of different aspects indicated that the most important global challenges of solar energy development were climatic challenges, technical constraints, and unwillingness to make investments. After describing current conditions and predicting the future of solar energy, this study analyzed the policies formulated by developed countries to develop this from of energy. Accordingly, China has gotten ahead of other countries in this industry due to the technological production of solar panels and governmental supports. Finally, the economic estimation of solar energy was presented by dealing with the economic barriers to this form of energy in developed countries. According to the significant growth in the reduction of solar energy electricity production cost, this source of energy can be used as a major source in the future. It was then recommended to use a hybrid of solar energy with other sourc...

Hydrogen production by steam-gasification is an interesting method compared to other common methods which has a wide range of applications including Proton Exchange Membrane (PEM) fuel cells and ga...

Due to environmental considerations and economic crisis, more attention has been paid to produce methanol from biomass. In this paper, to simulate the methanol production from air-steam gasificatio...

The main strategies for biomass utilization are the development of biomass-fired power plants, which can minimize the emissions and pollutants from fossil fuels combustion, the improvement of energ...

The best method for producing the required biodiesels is supercritical transesterification of triglycerides. The number of investigations about the prediction of biodiesels that yield supercritical fluids such as ethanol is not very much yet. In the recent decade, SVM was used very much as a data analyzing tool. Least Squares Vector Machine (LSSVM) method is a least square version of support vector machine. This method is capable of data analyzing and pattern recognizing, which cause that this method is popular in practical problems. The purpose of this study is evaluating the performance of Least Square Support Vector Machine (LSSVM) model in predicting the biodiesel yield as a function of temperature, pressure, reaction time, and ethanol/oil ratio. A genetic algorithm is capable to determine the optimal value of critical parameters. Based on the achieved results, it can be concluded that proposed LSSVM model is a reliable model for predicting biodiesel yield.

Sulfur particles, which could cause diseases, were the main powder of smog. And activated carbon had the very adsorption characteristics. Therefore, five sulfur particles were adsorbed by activated carbon and were analyzed by FT-IR. The optimal adsorption time were 120 min of Na2SO3, 120 min of Na2S2O8, 120 min of Na2SO4, 120 min of Fe2(SO4)3 and 120 min of S. FT-IR spectra showed that activated carbon had the eight characteristic absorption of S—S stretch, H2O stretch, O—H stretch, —C—H stretch, conjugated C 000000000000 000000000000 000000000000 111111111111 000000000000 111111111111 000000000000 000000000000 000000000000 O stretch or CC stretch, CH2 bend, C—O stretch and acetylenic C—H bend vibrations at 3850 cm–1, 3740 cm–1, 3430 cm–1, 2920 cm–1, 1630 cm–1, 1390 cm–1, 1110 cm–1 and 600 cm–1, respectively. For Na2SO3, the peaks at 2920 cm–1, 1630 cm–1, 1390 cm–1 and 1110 cm–1 achieved the maximum at 20 min. For Na2S2O8, the peaks at 3850 cm–1, 3740 cm–1 and 2920 cm–1 achieved the maximum at 60 min. The peaks at 1390 cm–1, 1110 cm–1 and 600 cm–1 achieved the maximum at 40 min. For Na2SO4, the peaks at 3430 cm–1, 2920 cm–1, 1630 cm–1, 1390 cm–1, 1110 cm–1 and 600 cm–1 achieved the maximum at 60 min. For Fe2(SO4)3, the peaks at 1390 cm–1, 1110 cm–1 and 600 cm–1 achieved the maximum at 20 min. For S, the peaks at 1630 cm–1, 1390 cm–1 and 600 cm–1 achieved the maximum at 120 min. It provided that activated carbon could remove sulfur particles from smog air to restrain many anaphylactic diseases.

Becoming a net importer of crude oil has encouraged China to develop new energy systems for heat and power generation. Increasing crude oil prices have increased the potential wide influence on Chi...

Dependence on natural gas and oil as the main energy carriers has led to serious economic crisis and climate changes, especially in developing countries like China. Among the different renewable biomass materials currently available for power generation, agricultural residue is one of the feedstocks receiving more attention from researchers in the field of energy and agricultural science, probably due to its availability, low price, and socioeconomic advantages. In this work, a detailed study of various scenarios for electricity production such as combustion, pyrolysis, and gasification was carried out. After a detailed comparison, it was found that the gasification process is a better energy system for electricity production because of its total cost and environmental problems are lower than those of other methods.

Macrophages are critical for regulation of inflammatory response during endotoxemia and septic shock. However, the mediators underlying their regulatory function remain obscure. Growth differentiation factor 3 (GDF3), a member of transforming growth factor beta (TGF-&beta, ) superfamily, has been implicated in inflammatory response. Nonetheless, the role of GDF3 in macrophage-regulated endotoxemia/sepsis is unknown. Here, we show that serum GDF3 levels in septic patients are elevated and strongly correlate with severity of sepsis and 28-day mortality. Interestingly, macrophages treated with recombinant GDF3 protein (rGDF3) exhibit greatly reduced production of pro-inflammatory cytokines, comparing to controls upon endotoxin challenge. Moreover, acute administration of rGDF3 to endotoxin-treated mice suppresses macrophage infiltration to the heart, attenuates systemic and cardiac inflammation with less pro-inflammatory macrophages (M1) and more anti-inflammatory macrophages (M2), as well as prolongs mouse survival. Mechanistically, GDF3 is able to activate Smad2/Smad3 phosphorylation, and consequently inhibits the expression of nod-like receptor protein-3 (NLRP3) in macrophages. Accordingly, blockade of Smad2/Smad3 phosphorylation with SB431542 significantly offsets rGDF3-mediated anti-inflammatory effects. Taken together, this study uncovers that GDF3, as a novel sepsis-associated factor, may have a dual role in the pathophysiology of sepsis. Acute administration of rGDF3 into endotoxic shock mice could increase survival outcome and improve cardiac function through anti-inflammatory response by suppression of M1 macrophage phenotype. However, constitutive high levels of GDF3 in human sepsis patients are associated with lethality, suggesting that GDF3 may promote macrophage polarization toward M2 phenotype which could lead to immunosuppression.

Here, the abilities of carbon nanocages (C60, C72 and C84) as anode electrodes in lithium-ion battery (LIB) and potassium-ion battery (KIB) were examined by theoretical method. The effects of adsorbed Gallium oxide (GaO) and Tin dioxide (SnO2) on performances of C60, C72 and C84 as anode electrodes in LIB and KIB were investigated. The cell voltage (Vcell), Gibbs free energy (Gad), band gap energy (EHLG) and charge transferred (q) of studied complexes were calculated. Results indicated that Gibbs free energies of adsorption of GaO on C60, C72 and C84 nanocages were higher than SnO2. The band gap energy of GaO-C84 was lower than GaO-C60 and GaO-C72. Results showed that adsorbed SnO2 and GaO can increase the |q|, |Gad| and Vcell values of C60, C72 and C84 nanocages, significantly. Finally, the C84-SnO2 as novel anode electrodes in LIB and KIB with the highest Vcell was proposed to use in electrical machines.

Psiguajdianone (

Improving the sustainability and cost-effectiveness of biochar production is crucial to meet increased global market demand. Here, we developed a single-step microwave steam activation (STMSA) as a simplified yet efficient method to produce microwave activated biochar (MAB) from waste palm shell (WPS). The STMSA recorded a higher heating rate (70 °C/min) and higher conversion (45 wt%) of WPS into highly microporous MAB (micropore surface area of 679.22 m2/g) in contrast with the conventional heating approach (≤ 12−17 wt%). The MAB was then applied as biosorbent for hazardous landfill leachate (LL) treatment and the adsorption performance was compared with commercial activated carbon under different pH, adsorbent quantity, adsorbate concentrations, and contact times. The MAB demonstrated high adsorption capacity, achieving maximum adsorption efficiency at 595 mg/g and 65 % removal of chemical oxygen demand (COD) with 0.4 g/L of adsorbent amount under optimal acidic conditions (pH ≈ 2–3) after 24 h of contact time. The Freundlich isotherm and pseudo second-order kinetic models were well-fitted to explain the equilibrium adsorption and kinetics. The results indicate the viability of STMSA as a fast and efficient approach to produce activated biochar as a biosorbent for the treatment of hazardous landfill leachate.

Exposures to particulate matter with a diameter of 2.5 μm or less (PM2.5) may influence the risk of birth defects and make you allergic, which causes serious harm to human health. Bamboo charcoal can adsorb harmful substances,that was of benefitto people’s health. In order to figure out the optimal adsorbtion condition and the intrinsic change of bamboo charcoal, five chemicals were adsorbed by bamboo charcoal and were analyzed by FT-IR. The optimal blast time was 80 min of Na2SO3, 100 min of Na2S2O8, 20 min of Na2SO4, 120 min of Fe2(SO4)3 and 60 min or 100 min of S. FT-IR spectra showed that bamboo charcoal had five characteristic peaks of S—S stretch, H2O stretch, O—H stretch, C 000000000000 000000000000 000000000000 111111111111 000000000000 111111111111 000000000000 000000000000 000000000000 O stretch or CC stretch, and NO2 stretch at 3850 cm−1, 3740 cm−1, 3430 cm−1, 1630 cm−1 and 1530 cm−1, respectively. For Na2SO3, the peaks at 3850 cm−1, 3740 cm−1, 3430 cm−1, 1630 cm−1 and 1530 cm−1 achieved the maximum at 20 min. For Na2S2O8, the peaks at 3850 cm−1, 3740 cm−1, 3430 cm−1 and 1530 cm−1 achieved the maximum at 40 min. For Na2SO4, the peaks at 3850 cm−1, 3740 cm−1 and 1530 cm−1 achieved the maximum at 40 min. For Fe2(SO4)3, the peaks at 3850 cm−1, 3740 cm−1, 1630 cm−1 and 1530 cm−1 achieved the maximum at 120 min. For S, the peaks at 3850 cm−1 and 3740 cm−1 achieved the maximum at 40 min, the peaks at 1630 cm−1 and 1530 cm−1 achieved the maximum at 40 min. It proved that bamboo charcoal could remove sulfur powder from air to restrain sulfur allergies.

Sulfur powder and sulfur dioxide (SO 2 ) often floated in air, produced acid rain and algal blooms, and could cause diseases. Bamboo charcoal could have adsorption and filtration properties. In order to figure out the optimal adsorption condition and the intrinsic change of the bamboo charcoal, five chemicals were adsorbed by bamboo charcoal and were analyzed by FT-IR. Fe 2 (SO 4 ) 3 ’s, Na 2 SO 4 ’s, Na 2 S 2 O 8 ’s, S’s, and Na 2 SO 3 ’s optimal adsorption condition was the concentration of 19 g/1000 g and stir time of 20 min, 21 g/1000 g and stir time of 60 min, 7 g/1000 g and stir time of 120 min, 11 g/1000 g and stir time of 120 min, 21 g/1000 g and stir time of 60 min, respectively. FT-IR spectra showed that for FT-IR spectra of Fe 2 (SO 4 ) 3 , the transmissivity of the peaks at 3435 cm −1 and 2925 cm −1 achieved the maximum for 60 min and the concentration was 19 g/1000 g, the transmissivity of the peaks at 1630 cm −1 , 1060 cm −1 and 660 cm −1 achieved the maximum for 60 min and the concentration was 7 g/1000 g. For FT-IR spectra of Na 2 SO 4 , the transmissivity of the peaks at 1630 cm −1 , 1060 cm −1 and 660 cm −1 achieved the maximum for 20 min and the concentration was 13 g/1000 g. For FT-IR spectra of Na 2 S 2 O 8 , the transmissivity of the peaks at 3435 cm −1 , 2925 cm −1 , 1630 cm −1 and 1060 cm −1 achieved the maximum for 120 min and the concentration was 19 g/1000 g. For FT-IR spectra of S, the transmissivity of the peaks at 3435 cm −1 , 2925 cm −1 , 1630 cm −1 and 1060 cm −1 achieved the maximum for 20 min and the concentration was 11 g/1000 g, 17 g/1000 g and 21 g/1000 g. For FT-IR spectra of Na 2 SO 3 , the transmissivity of the peaks at 3435 cm −1 achieved the maximum for 120 min and the concentration was 5 g/1000 g, the transmissivity of the peaks at 2925 cm −1 , 1630 cm −1 and 1060 cm −1 achieved the maximum for 120 min and the concentration was 11 g/1000 g. In these states, the number of the transmissivity of the maximum peaks is the largest.

Biomass gasification in circulating fluidized bed gasifiers (CFBGs) is regarded as one of the major options for clean heat and power generation, due to good gas-solid mixing. In this paper, we developed an Aspen Plus model to simulate the methanol production from biomass derived syngas by integrating the bed hydrodynamics and reaction kinetics. Particular emphasis placed on the influence of steam/biomass ratio (S/B), gasification temperature, equivalence ratio (ER), and biomass particle size (BPS) on methanol yield. The simulation results demonstrated that ER and gasification temperature are the most important factors in the process; higher ER and temperature contributed to lower and higher methanol yield, respectively. Model predictions were compared with available data from the literature, which showed fully good agreement.

In this paper, we developed a detailed process model to evaluate the potential of heat generation from biomass combustion in a CFB (circulating fluidized bed) combustor by coupling Aspen Plus simulator and dedicated FORTRAN subroutines. Mass yields of permanent syngas and solid char are simulated with respect to the pyrolysis temperature by a series of experimental correlations. Particular emphasis was placed on the influence of EOR (excess oxygen ration) upon released emissions and temperature. The parameter of biomass particle size was taken into account to evaluate its impact on combustion parameters and pollutants. To better understand the oxy-fuel combustion, the combustion efficiency (ηc) evaluated as a function of the equivalence ratio and EOR. In order to evaluate the influence of the metal catalysts on the reaction temperature and the concentration of air pollutants, an experimental study of catalytic combustion was also carried out. Model predictions were compared with available data from the literature, which showed fully good agreement.

The paper builds the mixing optimization model of the coal supply network of the low carbon economy based on the analysis of the impact on the optimization problems of the coal supply network. The method of carbon sequestration is used to measure carbon footprint and the cost and the paper brings this method into the coal supply network and optimization model to establish the hybrid optimization model, which integrates low carbon economy dimension of minimizing the total cost. The model is used to calculate the instance and verify the validity of the model. The research has decision-making application and reference value for building the coal supply network of low carbon economy.

This study aims to present an integrated process that can be used to produce biomedical and biological active components from the fruit shell of Camellia oleifera Abel. Through the Foss method, Aldehyde, acid compounds, acyl and alcohol compounds account for 22.7, 15.93, 0.24 and 61.13% of the extractives which were extracted from Camellia oleifera fruit shell by methanol solvents. Furfural, Pyrazole-4-carboxaldehyde, 1-methyl- and 5-Hydroxymethylfurfural account for 4.74, 1.22 and 58.78% of the extractives which were extracted from the fruit shell of Camellia oleifera Abel by ethanol solvents. Aldehyde, acid and amine compounds account for 5.01, 56.18 and 7.20% of the extractives which were extracted from the fruit shell of Camellia oleifera Abel by ethyl acetate solvents. The extractives of fresh flesh of bayberry were rich in rare drug, biomedical and biological activities.

This study examined the renewable energies and their impact on the economies of the Group of Seven (G7) countries. Results showed that the electricity produced from wind energy in the United States and then Germany is more than any other member countries. Due to its voluminous volcanoes, Italy has had favorable conditions for the development of geothermal energy, which has led it to be used as an efficient energy source in Italy. Results also showed that the installed capacity of geothermal systems is the lowest and hydropower systems are the highest in all G7 countries. It also concluded that, despite the high share of hydropower energy from total renewable energy capacity, the use of wind and solar energies is rapidly rising. As a result, it found that the development of solar energy occurs faster than the other renewable energies.

Among different renewable energies, the sun as an endless source of energy has been the focus of many researchers worldwide. The use of solar radiation energy in conventional power generation systems can play an important role in reducing fuel consumption and environmental pollution. The importance of this energy has been increased when we need to supply the load demand, especially in desert-like places. The main objective of this research is to propose a new optimal hybrid solar/diesel/battery system to cover the demand load of a rural part in the Gobi Desert in China. The main objectives for optimization are the loss of load probability, CO2 emissions value, and the annualized cost of the system. Here, the e-constraint method is adopted to simplify the multi-objective problem into a single objective problem. The optimization of the problem is performed by a developed version of the elephant herd optimization algorithm and the system sensitivity analysis has been analyzed on the parameters. Simulation results show that the proposed method can provide a reliable supplement for the load demand such that the PV penetration has a prominent impact by 97.9% of the costs. The results also present that the emitted CO2 gas by the proposed cEHO algorithm by 1735 kg/year is the minimum value compared with the PSO-based optimal system and HOMER software results. The initial capital cost of the system is also achieved 48,680 $ that specifies less value than the net present cost.

Design of electrodes that can simultaneously be excellent electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is important to produce hydrogen energy. In this study, Ni–Fe nanosheets were first created by electrochemical deposition method and then Mo-doped Ni–Fe nanosheets were created by hydrothermal electrode method. Then, electrode performance was investigated as electrocatalyst of HER and OER reactions. Morphology and microstructure of the electrodes were investigated using Field emission scanning electron microscopy (FESEM) and electrocatalytic activity was evaluated using LSV, Tafel test and EIS methods. The results of this study showed that among Ni–Fe electrodes sample, M-20 had the best electrocatalytic properties as well as molybdenum-doped electrode due to high surface area and also the synergistic effect of molybdenum doping showed better electrocatalytic behavior. In which, to generate a current density of 10 mA.cm−2 for the HER and OER, it required the 84 and 225 mV overpotentials, respectively. The electrode was also used as a bifunctional electrode for overall water splitting, which required a voltage of 1.81 V to generate a current density of 100 mA.cm−2. This study introduces an economical and effective method for the synthesis of electrocatalysts with appropriate activity.

Inspired by the huge number of investigations on the applications of two-dimensional materials in nanoscale electronic devices, we examined the equilibrium structures and electronic properties of arsenene nanosheets doped with different domains of silicene, germanene, and stanene. In this regard, we replaced one hexagonal ring of arsenene with Si, Ge and Sn atoms to obtain the novel hybrid nanomaterials with unique properties. Due to the larger buckling parameter of arsenene compared to the silicene and germanene, the Si and Ge domains show less protrusion out of the surface of arsenene. On the other hand, since the Sn atom has higher atomic radius than the As atom, the protrusion observed for stanene domain in the arsenene structure will be greater. The band structure calculations show that the considered supercell of arsenene is semiconductor. The Si, Ge, and Sn domain doped monolayers also exhibit semiconductor feature, although they have narrower energy band gaps than the perfect arsenene system. Our theoretical computation would offer valuable insights into the domain doping influence on the geometric and electronic properties of the arsenene monolayer, and shed light on the application of Si-, Ge-, and Sn domain doped arsenene systems for the future nanoelectronic devices.

In order to ensure the safety of various buildings, the application of concrete cut off wall in various buildings is more and more extensive. The stress of cut off wall is directly related to the stability of the wall. At present, many scholars have made in-depth research on stress analysis of concrete cut off wall. With the development of big data analysis technology, it has been applied to stress analysis of cut off wall. With its application and further research, it can be found that there are some common problems in stress analysis of concrete cut off wall based on big data analysis, which affect the accuracy of analysis results. Therefore, it is urgent to study these problems in depth. Based on the analysis of big data, this paper collected and processed the stress data of cut off wall in detail, and obtained the common problems in stress analysis of concrete cut off wall with the help of clustering analysis algorithm, and put forward relevant improvement Suggestions on this basis. It not only guarantees the accuracy of the stress analysis results, but also has reference significance for the future related research.

Cui, Y.; Xu, D.Y.; Liu, Z.L., and Ross, D., 2020. Global research and trends in renewable energy: Ocean waves, tidal energy and offshore wind. In: Malvarez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 1485-1489. Coconut Creek (Florida), ISSN 0749-0208.The purpose of this study is to reveal the research trends of scientific outputs on marine renewable energy from ocean for the past 30 years and provide a potential guide for future research. A method of scientometric analysis was performed, based on the online version of the Web of Science and Scopus from 1990 to 2019. The authors evaluated the publication types, source countries, journals, the patterns of publication outputs, most cited articles, most-productive authors, institutional distributions, subject categories, high-frequency keywords in the 1,246 publications of marine renewable energy in total. The research results show that the general most concerned topics of are “renewable energy” “wave energy” “marine renewable energy” “ocean energy” and “tidal energy”, but the bioenergy has increasingly attracted more attention.

Using the first-principles calculations, we have systematically examined the adsorption of gas molecules on the pristine and vacancy defective stanene monolayers. The adsorption of gas molecules on the defective monolayers is much stronger than that on the perfect ones, indicating the suitability of defective stanene nanosheets for adsorption processes. The large adsorption energies for SO2 and SO3 adsorbed complexes indicate the strong reactivity of stanene systems with adsorbed gas molecules, leading to the formation of multiple contacting points at the interface. The formation energies for the defective stanene systems were calculated. Our results indicated that the single vacancy defective stanene monolayers are thermodynamically stable, and can be used as effective gas sensors. The charge density difference calculations indicate that the electronic densities were largely accumulated between the atoms interacting with each other. This strong chemical interaction was also evidenced by the large overlaps of the density of states between the interacting atoms. The band structure calculations reveal the semiconductor features for defective stanene monolayers with adsorbed gas molecules. Our obtained results would be useful to search for promising gas sensor devices based on vacancy defective stanene monolayers.

The ultrasound wave assisted synthesis of a novel ZnWO

Some limited models have been suggested to determine the conductivity of polymer carbon nanotube (CNT) nanocomposites (PCNTs). However, earlier models (e.g., the Kovacs model) cannot properly consider the roles of the interphase regions or tunneling properties on the percolation threshold and subsequent conductivity of PCNTs. In this paper, the Kovacs model is further developed by assuming that the CNT, interphase, and tunneling regions are separate phases. Also, some simple equations are provided to calculate the percolation threshold as well as the volume fractions and resistances of the CNT, interphase, and tunneling regions in conductive networks. The experimental conductivity results for several samples are compared with the predictions of the developed model. In addition, the calculations of the developed model at different parameter levels are explained and justified. The conductivity calculations show good agreement with the experimental data. Moreover, the developed model reasonably explains the roles of the different parameters on the conductivity. For example, long, thin, and straight CNTs efficiently improve the conductivity because they form large networks in the nanocomposites. Additionally, a thick interphase enlarges the conductive networks, resulting in a desirable conductivity. The conductivity of PCNTs only depends on the tunneling resistance; this is the case because the poor resistance/significant conductivity of the CNT and interphase regions do not influence the conductivity. The developed equations can replace conventional approaches for predicting the conductivity of nanocomposites.

Employing the antibacterial property of industrial bamboo vinegar (IBV) and the photocatalytic degradation of TiO2, bamboo macromolecules were pretreated and processed into nonvolatile and antibacterial bio board (NVABB). The NVABB was then analyzed by conducting Fourier-transform infrared spectroscopy, thermogravimetric analysis and differential thermal analysis. Results show that NVABB samples had average density of 0.96 g/cm3, which is appropriate for application. In terms of physical and mechanical properties, the best NVABB sample obtained from IBV, TiO2 and bamboo had an IBV pretreatment time of 10 min, 2% TiO2 and 1% bamboo charcoal. Fourier-transform infrared spectroscopy demonstrated that optimum conditions for hot pressing were a temperature of 170 °C, duration of 15 min and the addition of IBV and TiO2. Thermogravimetric analysis/differential thermal analysis curves suggest that the thermal degradation of NVABB was less than that of bamboo and that hot pressing obviously increased the thermal stability of HDBB samples. Analysis of the antimicrobial effect revealed that IBV pretreatment improves the antibacterial property of NVABB. Keywords: Industrial bamboo vinegar, Nonvolatile and antibacterial bio board, Bamboo macromolecules, Fourier-transform infrared spectroscopy, Thermogravimetric analysis/differential thermal analysis