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Ni-Co bimetallic catalysts supported on coconut shell activated carbon are synthesized using solid-phase method and investigated for dry reforming of methane, to explore the impact of Ni:Co ratio on the catalyst activity and stability. The catalyst performances are evaluated under the temperature varying from 600 to 900 °C and gas hourly space velocity (GHSV) of 7200 mL/h·g-cat. The characterization results show that metal nanoparticles are produced on the support, and the bimetallic catalyst with an explicit Ni:Co ratio (2:1) is the most beneficial for metal particle dispersion and acquires the minimum particle size of 4.41 nm. The bimetallic catalysts with an explicit Ni:Co ratio of 1:2 and 1:1 exhibit a synergistic effect towards the conversions of CH

In this study, a new method of microwave-induced discharge over biomass-derived char (i.e., bio-char) spherical carriers was proposed. Bio-char spherical carriers were obtained through rational forming. The discharge intensity and temperature increase under discharge were measured to elaborate the quantitative relationship between microwave discharge and the temperature increase. The effect of bio-char properties on microwave-induced discharge was investigated. The results revealed that discharge achieved the highest electric–thermal conversion efficiency of 61.04%, and the heat generation ratio through the discharge in the initial 10 min was up to 69.08%. The graphitisation degree and transmission depth of microwaves can affect discharge intensity. A critical light intensity inducing hot spot effect exists under different working conditions, and exceeding the critical value led to the hot spot effect and a sudden increase in bed temperature, with a corresponding range of 2.48–5.76 V. The maximum temperature under microwave discharge reached 981 °C, with a heating rate of 376.4 °C/min. The method is potential in the field of value-added utilization of bio-char and microwave-promoted chemical processes.

To overcome water instability and low photocatalytic activity of lead-free halide perovskite for the degradation of organic dyes, we report a novel photocatalyst of lead-free halide perovskite with Na incorporation and employ it for the photocatalytic degradation of organic dyes in water solution under visible light irradiation. The main purpose of this work is to confirm the feasibility of lead-free halide perovskite with Na incorporation for improving the photocatalytic efficiency and recyclability in water solution and further to explore the mechanism behind the enhancement of photocatalytic performance after Na incorporation. The results show that Cs2Ag0.60Na0.40InCl6 can increase the dye degradation rate by at least 50% than the lead-free halide perovskite (Cs2AgInCl6) and the photocatalyst of Ag substituted by Na (Cs2NaInCl6). The degradation efficiency of rhodamine 6G catalyzed by Cs2Ag0.60Na0.40InCl6 reaches 94.94% over 60 min, which is 72% higher than that catalyzed by Cs2NaInCl6 and 27% higher than that catalyzed by Cs2AgInCl6. What's more, the degradation efficiency of methyl orange catalyzed by Cs2Ag0.60Na0.40InCl6 is 90.39% within 150 min, which is 66% higher than that catalyzed by Cs2NaInCl6 and 54% higher than that catalyzed by Cs2AgInCl6. Moreover, the photocatalyst of Cs2Ag0.60Na0.40InCl6 exhibits a desirable recyclability by water exposure, retaining the degradation efficiency over 90% after five cycles. The strengthened photocatalytic performance in the presence of Cs2Ag0.60Na0.40InCl6 is ascribed to an increase of radiative recombination rate and an improvement of average lifetime to 204 ns since an appropriate Na incorporation at the atomic ratio of Na/Ag=4:6 breaks the original crystal lattice and meanwhile increases the electron and hole overlap. The work proves a great potential of halide perovskite with Na incorporation for the highly efficient photocatalytic degradation of organic dyes in water solution.

Two-dimensional (2D) organic–inorganic hybrid perovskites are promising for next-generation optoelectronic materials due to their enhanced stability, controllable quantum well thickness and excellent photoelectric properties. The growth of large lateral size, small thickness and high-quality single crystal films is necessary for the practical application of devices. Herein, we report a gas–liquid interface crystalline route to grow BA2PbBr4 (BA = CH3CH2CH2CH2NH3+) single crystal films and achieve wafer size (38 cm2) and thinness as little as 78 nm (aspect ratio > 105). Moreover, an ultraviolet-photodetector of the single crystal thin film presents a dark current of ∼10−14 A, a detectivity of ∼1012 Jones and fast response time (τrise = 9.7 ms and τdecay = 8.8 ms). Our work provides a way to grow 2D perovskite single crystal films with large size and small thickness, which is significant for the development of perovskite-type high-performance optoelectronic devices.

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.

Removal of biomass tar is of importance for biomass gasification technology, since the existence of tar can cause tremendous problems, such as lowering heat transfer efficiencies and blocking the filters and pipes, etc. A typical one-ring aromatic hydrocarbon (i.e., toluene) is chosen as model compounds to investigate tar cracking and reforming performance with microwave heating, catalyzed by biomass-derived char (Bio-char). The adopted chars consist of original char obtained by microwave or electrical heating, an in-situ activated char as well as metal-impregnated char. For the cracking process, original char achieved with microwave heating exhibits better catalytic activity, compared to that achieved with electrical heating. It is further compared activated char is more active to toluene cracking and an activated char impregnated by Ni shows the most desirable performance to this process. A process of mixed reforming comprised by steam and dry reforming presents an evident superiority in terms of toluene conversion and catalyst stability, which can achieve an average conversion of 95.19% and a minor mass loss of 2.2% occurred in the used char during 120 min. It is calculated energy efficiency of a microwave-assisted combined reforming system at lab-scale is up to 57.8%.

As a new member of the group of promising 2D materials, MXene shows the advantages including metallic conductivity, high charge carrier mobility, tunable band gap, flexibility and diverse surface c...

In order to inhibit the apparent metal agglomeration and carbon deposition of the catalysts during the dry reforming of methane (DRM), the nickel nanoparticles supported over different types of activated carbon (AC) are synthesized by the solid-phase method. The main purpose of the work is to reveal the correlation of the support properties on the catalyst activity, and explore the effect of the support properties on the enhancem;ent of catalyst performance in the reforming process. The results show that the catalyst using AC1 as the support has the more uniform metal dispersion and form the least nickel nanoparticles of 4.11 nm, due to higher carbon content and the more developed surface area of AC1. It is also found that the catalyst prepared using AC1 shows high catalytic activity and long-term stability. Moreover, the catalyst of Ni/AC1 presents a self-enhancement of catalytic activity in the reforming process and promotes the conversion rates of CH4 and CO2 to 94.1% and 96.5%, respectively over 12 h. No obvious metal agglomeration is existed on the catalyst of Ni/AC1 after the reforming testing of 12 h. Meanwhile, the carbon deposit has little effect on catalytic performance, and metal agglomeration is the main affecting catalytic performance. In addition, the syngas generated using Ni/AC1 has a favorable H2/CO ratio of 1.

To develop a new method to recover elemental sulfur from the desulfurization process, a study on the sulfur evolution mechanism during the reduction of SO2 with CO over carbon was carried out. Ther...

Biochar obtained from microwave pyrolysis of corn stalk was employed for catalyzing tar reforming, using toluene as the representative. Catalytic performance of different biochar and toluene reforming with a mixed agent of CO2 and H2O were focused on. By comparison, it was found Fe-doped activated char exhibited a relatively steady capability on toluene CO2 reforming, with an average conversion of 94.3% in whole test of 150 min. This was due to this char had a large surface area of 321.2 m2/g and the advanced pore structure. The other reason to this was the formation of pure iron and iron carbide during toluene reforming. Synergetic effect arose in toluene combined reforming was validated, through comparing the actual conversion from combined reforming with the weighed conversion from two individual reforming with CO2 or H2O. Synergetic effect was influenced by temperature and it was highlighted at 800 °C, with a mean conversion of 94.8% within a test of 150 min. Meanwhile, increasing molar ratio of CO2 to H2O could enable the strength of synergetic effect. At the biggest ratio of 2:1, the actual conversion from toluene combined reforming was 12.3% higher than the weighed conversion from two single reforming.

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.

For value-added utilization of high-humidity lignite, an investigation on its drying behavior was carried out, using a method of Microwave Thermogravimetric Analysis (MTGA). The characteristic of h...

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.

To overcome water instability and low photocatalytic activity of lead-free halide perovskite for the degradation of organic dyes, we report a novel photocatalyst of lead-free halide perovskite with Na incorporation and employ it for the photocatalytic degradation of organic dyes in water solution under visible light irradiation. The main purpose of this work is to confirm the feasibility of lead-free halide perovskite with Na incorporation for improving the photocatalytic efficiency and recyclability in water solution and further to explore the mechanism behind the enhancement of photocatalytic performance after Na incorporation. The results show that Cs

Microwave lignite drying with assistance of biomass-derived char was addressed and effect of bio-char on drying rate and energy consumption was investigated in this work. Effective diffusion coefficient and activation energy for the drying process were also analyzed. The results indicated the drying process was largely dependent on the variation of sample temperature. Bio-char originated from pine wood was most favorable for lignite drying, considering its better promoting effect and advanced security. There existed an optimal bio-char addition ratio for drying process at different power. The corresponding optimal ratio was 10% at 231 W and 15% at 385 W, at which the biggest drying rate and the least energy consumption were reached. It was compared lignite drying initiated at 385 W was better for energy conservation. Effective diffusivity was improved and activation energy was simultaneously reduced, with the addition of bio-char. The minimum activation energy was 15.54 W · g−1, which was gained a...

The reforming of methane by CO2 and H2O on biomass-derived char (bio-char) was run in a lab-scale microwave oven (2.45 GHz). Special attention was dedicated to the effect of bio-char and energy utilization for the reforming reaction. Through comparing CH4 conversion from combined reforming and the weighted value of CH4 conversion from two individual reaction: steam reforming and dry reforming, synergetic effect on CH4 conversion was confirmed at 900 °C in combined reforming. This effect was attributed to less carbon consumption of bio-char in combined reforming and it was significantly influenced by the contained metal in bio-char. Alkaline metal and alkaline earth metal in bio-char were favorable for improving the conversion of CO2 and CH4, respectively. Through comparison, the mixture of demineralized bio-char and nickel-based catalyst was the most effective to promote combined reforming. Energy efficiency was related to temperature and it was maximized to be 49.2% at 800 °C. The changes of energy efficiency during the reforming process was similar to the variation of CH4 conversion with time. Specific energy consumption for producing per m3 of syngas was 4.14 kW·h, with a scale-up microwave-assisted combined reforming process as the model.

In the present work, a method of pyrolyzing forestry waste (FW) under microwave-metal interaction was proposed. The kinetic analysis of the process was carried out using a microwave thermogravimetric analyzer. The mechanism of FW pyrolysis under microwave-metal interaction was discussed from the perspective of microwave-induced metal discharge and non-discharge processes. The initial pyrolysis temperature Ti reduced, and the maximum pyrolysis rate Rm and pyrolysis characteristic index S increased by employing a method where microwave and metal were coupled. The number of metals inserted also significantly affected the pyrolysis behavior. Rm in the presence of one metal was 92.3% higher than that recorded in the absence of metal. The results of kinetic analysis revealed in the presence of metal, the activation energies at 400 W and 560 W were 51.7% and 57.5% lower, respectively, than the activation energy recorded in the absence of metal. Multiple effects of light, heat, and plasma produced by microwave-induced discharge caused the local pyrolysis of FW. The promotion of FW pyrolysis in the non-discharge stage was primarily caused by the microwave absorption of carbon into heat and the conversion of current on the metal surface into Joule heat.

This paper concerns microwave-assisted methane reforming with or without water. In this work, a heterogeneous mixture of biomass derived char (i.e., bio-char) and a commercial nickel-based catalyst is used for the reforming reaction. The obtained conversions, equivalent carbon consumption, energy efficiency and consumption are focused on. Ni/bio-char with the weight ratio of 10% imposes better activity than others. Equivalent carbon consumption on these materials initially decreases with time and tends to be stable afterward. Carbon consumption in bio-char is relieved when using Ni/bio-char with the ratio ranged from 5% to 10%. Energy efficiency is dependent of the used material and the reforming temperature. The optimized efficiency under the higher temperature is obtained on Ni/bio-char with the lower ratio. Energy consumption on Ni/bio-char with the ratio of 10% is 7.9 kW h−1 of per m3 of syngas produced and this value is lower than others. From the point of the conversions, carbon consumption and energy utilization, Ni/bio-char with the ratio of 10% is favorable for the reforming reaction. The obtained conversions and the H2/CO ratio are promoted in mixed reforming on Ni/bio-char.

Methane reforming by CO2 and H2O is performed in this study, using the char derived from biomass as catalyst. The catalytic effect of bio-char on CH4 reforming is examined by changing feed composition, reforming temperature and heating method. At an appropriate H2O/CO2 ratio, combined reforming achieves higher CH4 conversion at the same temperature than dry reforming, and it also brings about an increase in the H2/CO ratio of syngas production. The results indicates that synergetic reaction of CH4–H2O and CH4–CO2 can be reached in combined reforming at the temperature of 800–1000 °C. Microwave heating presents a promising method to enhance the reforming reaction. Bio-char exhibits better performance for combined reforming, because it optimizes the competition between carbon deposition and carbon consumption. This is evidenced by less equivalent carbon consumption and the slower deterioration of porous properties. Carbon deposition and carbon consumption from the catalyst contribute to the deactivation of bio-char.

The interaction event between programmed death receptor-1 (PD-1) and its ligand (PD-L1) functions as an essential immune checkpoint against cytotoxic T effector cell activation. Previously, a number of small-molecule inhibitors and antibody drugs have been successfully developed to block the PD1/PDL1 signaling axis for breast cancer immunotherapy. Here, we attempt to directly disrupt the formation of PD-1/PD-L1 complex by using a self-inhibitory peptide (SIP) strategy. In the procedure, the complex crystal structure is examined systematically with energetic analysis and alanine scanning. Two double-stranded segments I and II in PD-L1 active finger are identified as hotspot regions; they directly interact with the amphipathic pocket of PD-1 to form the complex system. The segments are derived from PD-L1 to define two SIP peptides, namely, DS-I and DS-II, which are thought to have capability of rebinding at the complex interface, thus disrupting PD-1/PD-L1 interaction as a new immune checkpoint blockade. A further analysis reveals that the free linear DS-I and DS-II peptides are highly flexible without protein context support, which would incur a large entropy penalty (unfavorable indirect readout effect) when rebinding to PD-1. Next, intramolecular cyclization is applied to constraining the intrinsically disordered conformation of free DS-II peptide into native ordered double-stranded configuration, which can be substantiated by molecular dynamics simulation and circular dichroism spectroscopy. Several cyclized counterparts of linear DS-II peptide are designed and their affinities to PD-1 are determined using fluorescence polarization assays. As might be expected, three designed cyclic peptides DS-II[c111–127], ΔDS-II[c111–127] and ΔDS-II[c110–128] exhibit considerably increased potency (Kd = 28.0 ± 4.2, 17.5 ± 3.1 and 11.6 ± 2.3 μM, respectively) relative to linear DS-II peptide (Kd = 109 ± 15 μM).

The objective of this work was to investigate the ability of char from biomass microwave pyrolysis at 800 °C for tar removal, using toluene as the model compound. The experiments were conducted in a fixed bed with microwave heating and electrical heating, respectively. Carbon weight in biomass char was calculated after the experiments, and the chars were characterized by Brunauer–Emmett–Teller (BET) analysis and Scanning Electron Microscope (SEM) measurement. The results indicated that microwave heating had a promoting effect on toluene conversion. With the temperature increasing to 750 °C, cracking conversion and hydrogen selectivity rose respectively to 92.77% and 91.74%. CO 2 reforming of toluene was effective to produce more syngas. An optimum CO 2 flow rate, i.e., 80 mL min −1 , was existed under microwave heating. In this case, toluene conversion reached a maximum of 92.03%, and the syngas yield also increased to 91.03%. The ratios of H 2 /CO exhibited a substantial reduction with increasing CO 2 flow rate. At CO 2 flow rate of 100 mL min −1 , the ratio approached stoichiometric ratio in reforming reaction, and the ratio further reduced to 0.22 at CO 2 flow rate of 120 mL min −1 . Toluene reforming displayed a relative stable performance for the conversion of toluene, since the existence of CO 2 efficiently relieved biomass char deactivation. Toluene reforming conversion retained at about 86% in a time range of 20–140 min. Carbon gasification during the reforming reaction possessed a resistance to carbon deposition, but it simultaneously caused carbon loss in biomass char. The most serious weight-loss ratio was 5.42% in this work, obtained at CO 2 flow rate of 120 mL min −1 . The consumed carbons were gasified into part of syngas production and provided the biggest contribution of 15.4% to final syngas production.

The catalysts for methane dry reforming were commonly confronted with the problems of metal component agglomeration and carbon deposition. The catalysts made by solid-phase synthesis could effectively overcome these problems. In this paper, methane dry reforming was catalyzed over activated carbon supported Ni-catalysts prepared by solid-phase synthesis. Through this method, the catalysts exhibited a uniform metal dispersion over the carrier, with particle size at the nanoscale of 4.69 nm. Catalytic performance of the prepared catalysts was tested, and the results showed that the catalysts could effectively catalyze methane dry reforming, due to little metal agglomeration and the balanced competition between carbon deposition and carbon consumption. In the catalytic performance testing initiated at 900 °C, the conversions of CH4 and CO2 were maintained at 80.3% and 97.5% after the testing, respectively. It was also noticed the syngas generated in the testing process had a favorable H2/CO ratio, at around 1. The syngas was considered to be beneficial to the synthesis of methanol, ammonia and oxygen-containing chemicals by Fischer-Tropsch process. It should be emphasized the reactant gases conversions presented an upward trend when the testing arrived at about 2 h, revealing an enhancement of catalyst activity. In totally, the catalysts prepared by solid-phase synthesis could avoid the agglomeration of active component and the serious carbon deposition, thus slowing down the catalyst deactivation. Through this work, it was demonstrated solid-phase method could open up new possibilities for the synthesis of highly active and stable catalysts for methane dry reforming.

The effect of activated carbon as catalyst on methane dry reforming is investigated in this work. Gases conversions in CH4 decomposition, carbon gasification and CH4 dry reforming are also compared. It is compared wood-derived activated carbon exhibits better catalytic effect on methane reforming. The results indicate CH4 conversion in the reforming reaction is higher than that in the decomposition reaction, with a maximum difference of 37.9%. CO2 conversion in the reforming reaction is lower than that in carbon gasification reaction by 18.4%. Various variables are employed to determine the optimum conditions for reforming reaction. The results reveal the enhanced conversions of CH4 and CO2, accompanied by a decreased H2/CO ratio can be achieved through increasing microwave power, reducing CH4/CO2 ratio or decreasing gas flow rate. Furthermore, migration amount of carbon is calculated. It is obtained carbon migration rate reduces with the increase of microwave power or decrease of CH4/CO2 ratio. At last, catalytic activity of wood-derived activated carbon is tested. It is noticed the catalyst presents high catalytic activity at the beginning, followed by a sharp loss of catalytic activity after 40 min. This caused the decrease of CH4 and CO2 conversions nearly by 56.6% and 36.6% after the test, respectively.

A process of combining methane dry reforming and biochar steam gasification was conducted under microwave heating, using biochar as a catalyst in the reforming process and as a fuel in the gasification process. Through this process, biochar was efficiently utilized and the desired syngas production was obtained. The influences of various parameters consisting of heating mode, temperature, inlet gas composition and addition of metal component on methane conversion and the evolution of biochar remained mass ratio in the whole process of 4 h were focused on in this article. Besides, syngas yield and H2/CO ratio achieved under different conditions were compared. Microwave heating was more capable of favoring this process than electric heating, which could promote methane conversion by 12.1% and increase the decline of remained mass ratio by 9.2% in the gasification process. Overall, the process initiated at 800 °C was more efficient than that initiated at the other temperature. The reforming process was optimized at an equable distribution of CH4 and CO2. Nevertheless, the best reactivity in the first 60 min of gasification process was occurred on biochar obtained from the reforming process with CH4/CO2 ratio of 1:1.5, featured by a reduction of remained mass ratio up to 16.1%. Compared with the use of pure biochar, the addition of Fe improved methane conversion by 3.6%, but also enhanced biochar gasification reactivity, with biochar remained mass ratio dropped to 51.9%. The maximized syngas yield was 93.2% in this paper, together with H2/CO ratio at 0.98.

Microbe cement, as a new green binder, relies on microbial-induced calcium carbonate precipitation and could consolidate loose particles to a whole body (bio-sandstone). The mechanical properties of sandstone cemented by microbe cement for different numbers of injections were investigated. The results show that the compressive strength of bio-sandstones increases with injection number: the average compressive strength of bio-sandstones could be up to 6·1 MPa after 14 injections of microbe cement. In addition, the rate of increase of compressive strength decreases with an increase in the number of injections. The microstructure of bio-sandstones with different numbers of injections was analysed by means of scanning electron microscopy. The results indicate that the microstructure of the bio-sandstones became increasingly dense with an increase in microbe cement injections.

Microbe cement as a biogrouting could consolidate loose particles to improve mechanical properties. Microbe cement has drawn much attention because of the ever increasing awareness of environmental protection. This paper confirms the feasibility of binding loose sand particles using microbe cement and details the cementation mechanism of microbe cement. In addition, the microstructure and properties of representative bio-sandstones have been analyzed by X-ray computed tomography (XRCT), Scanning electron microscopy (SEM) and Mercury Intrusion Porosimetry (MIP). The experimental results indicate that the compressive strength of bio-sandstone could be up to 6.1 MPa and the bottom region microstructure in bio-sandstone is denser and less fragile than the top region due to more calcite precipitated in the former one.

A new generation of cement, microbe cement has been developed due to the ever increasing awareness of environmental protection. Microbe cement is a new strengthening technique based on microbiologically induced precipitation of calcium carbonate. This paper confirms the feasibility of microbe cement binding loose sand particles and presents results from a laboratory research on the influence of molding process (non-pressure molding, pressure molding, discontinuous non-pressure molding and pumping molding) on the mechanical properties of sandstone microbe cement bound. The results showed that the ways of molding procedure had a strong influence on the mechanical properties of bio-sandstone. The strength, which was up to 12.0 MPa, of sandstone microbe cement bound by adopting pumping molding process was higher than other three processes. Meanwhile, Scanning electron microscope (SEM) image analysis technique was adopted to measure the corresponding variation of porous characteristics caused by different molding processes. The results indicate that the microstructure of bio-sandstone adopted by pumping molding has lower porosity and higher content of precipitated calcium carbonate than other three molding processes.

The learning of power system relay protection requires some practical drills. Laboratories have therefore been built in campus and the experiment teaching has been carried out. However, in distance education, the actual presence of the students in the laboratories is practically impossible. To overcome this problem, power system relay protection experiment in E-learning has been developed. An experiment system of relay protection was developed and the Elearning links were designed. It enables autonomous, interactive and collaborative learning of relay protection experiment through the Internet. In fact, students can learn at any time any place. This system will therefore enhance students’ experimental skills and improve experimental teaching quality.

A microwave reactor (MWR) was designed to investigate microwave-induced pyrolysis of biomass. Condensation of tars on the quartz reactor and the pipelines was prevented by an electric heating device, and a temperature control function allowed determination of product characteristics at constant temperatures. Temperature had an important influence on microwave pyrolysis; the yields of gas products increased from 17.69 wt.% to 22.27 wt.% and the ratio of combustible gas to total gas products increased from 67.21 vol.% to 77.14 vol.% as the temperature increased from 400 °C to 600 °C. A large number of volatiles was released as temperature increased, resulting in an increase in the number of pores of the coke and a uniform pore structure was obtained. The specific surface area of coke increased from 0.89 m2/g (400 °C) to 9.81 m2/g (600 °C) and the pore volume increased from 0.006 cm3/g (400 °C) to 0.012 cm3/g (600 °C), but the average pore size decreased from 282.16 nm (400 °C) to 46.64 nm (600 °C).

The compressed wheat and corn straw bale were pyrolyzed on a microwave heating device self-designed and built with respect to the time-resolved temperature distribution, mass loss and product properties. Considering scale up and technology promotion of microwave pyrolysis (MWP), the investigations on electricity consumption and energy balance of MWP were carried out emphatically. The results indicated that MWP had obvious advantages over conventional pyrolysis, such as heating rapid and more valuable products obtained. The distribution of pyrolysis products such as gas, liquid and char was close to 1:1:1 due to the medium pyrolysis temperature and the slow heating rate, which was not favorable for the formation of gas and/or liquid products. The content of H2 attained the highest value of 35 vol.% and syngas (H2 and CO) was greater than 50 vol.%. The electricity consumption of MWP was between 0.58 and 0.65 kW h (kg straw)−1 and with the increase of microwave power, the electricity consumption required for pyrolysis of unit mass of straw increased. The minimum microwave power for MWP was about 0.371 kW (kg straw)−1 and the proportion of heat loss and conversion loss of electricity to microwave energy occupied in the total input energy was 42%. Data and information obtained are useful for the design and operation of pyrolysis of large-sized biomass via microwave heating technology.

The microwave pyrolysis technology, which can overcome the disadvantages of conventional pyrolysis methods such as heating slow and necessity of feedstock shredding, has been used to pyrolyze the corn stalk bale. The experiments were carried out with respect to the time-resolved temperature distribution, mass loss and product properties. In order to get a deeper understanding, the traditional pyrolysis using electric heating method was also performed. The comparison results indicated that microwave pyrolysis had obvious advantages over electric heating pyrolysis, such as heating rapid and uniform, more valuable products obtained. The content of H 2 attained the highest value of 35 vol.% and syngas (H 2 and CO) was greater than 50 vol.%. Material properties, heat and mass transport mechanisms, as well as chemical reactions had significant influences on the microwave pyrolytic characteristics. Data and information obtained are useful for the design and operation of pyrolysis of large-sized biomass via microwave heating technology.

In this paper the reforming of CH 4 with CO 2 was conducted in the integrated microwave-assisted heating system, with the wood-derived activated carbon as catalyst. At first, the reactant gases conversions of CH 4 decomposition, CH 4 /CO 2 reforming and CO 2 gasification were compared, and the temperature rising characteristic of the activated carbon was tested. And also the influence of operating parameters, including temperature, the CH 4 /CO 2 ratio and gas flow rate, on the CH 4 and CO 2 conversions was evaluated. By comparing CH 4 decomposition, CH 4 /CO 2 reforming and CO 2 gasification, it can be concluded that the presence of CO 2 is suitable for maintaining the catalytic activity of activated carbon. And the activated carbon is demonstrated to be an excellent microwave receptor. An increase in the CH 4 and CO 2 conversions can be achieved through increasing temperature, decreasing the CH 4 /CO 2 ratio or reducing gas flow rate.

The processes and routes of syngas production from biomass gasification were first outlined, and the key processes of this technology were highlighted in the paper. Simultaneously, the cost of syngas production from biomass gasification was evaluated to be RMB 1.05/Nm 3 when the handling capacity of gasifier, material cost and system operating rate is separately fixed to be lton/h, RMB 250/ton and 0.8. On this basis, the influences of these three aspects (handling capacity of gasifier, material cost and system operating rate) on the syngas production cost were analyzed. It could be concluded that the reduction in the syngas production cost could be achieved by raising handling capacity of gasifier, reducing material cost and enhancing system operating rate. Finally, the prospect of this technology was put forward from technical and economic points of view.

The direct pyrolysis of large size biomass is a difficulty, and it seems to be that microwave pyrolysis is a novel process to overcome the problem. This paper presents the experimental results of microwave pyrolysis process for straw bales in a microwave thermogravimetric analyzer the first time. TG and DTG analysis techniques are adopted to study the pyrolysis behaviors of straw bales systematically. The experimental results show that the input power of microwave, heating time and temperature have important effects on pyrolysis process. Reaction kinetics for microwave pyrolysis of straw bale is analyzed theoretically. A one-step comprehensive model is used to describe the microwave pyrolytic reaction in this experiment. The activation energies for the corn and wheat straw under microwave power of 334 and 668 W/ (kg straw) are 24.4, 26.8 kJ/mol and 67.2, 70.3 kJ/mol, respectively, the pyrolytic reaction is first order. The activation energy and pre-exponential factor increase with the increasing of microwave power. The experiment of microwave pyrolysis provides a new method for the wide uses of straws.