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The key to "dual carbon" lies in low-carbon energy systems. The energy internet can coordinate upstream and downstream "source network load storage" to break energy system barriers and promote carbon reduction in energy production and consumption processes. This article first introduces the basic concepts and key technologies of the energy internet from the current situation of energy supply and demand in China. Second, this paper proposes to create an energy internet with coordinated and complementary "source network load storage" and to construct a new type of power system with six new characteristics in this context. Finally, combined with an example of the energy internet demonstration project, this paper analyses and summarizes the value creation and business type innovation of the energy internet from three aspects: power market mechanisms, comprehensive energy services, and low-carbon energy diversification, and it looks ahead to the future direction of energy internet construction. [ABSTRACT FROM AUTHOR]

This study explored the composition and energy potential of university solid waste (USW) in China. Five combustible components, namely hard plastics (HP), paper (PP), soft plastics (SP), biomass (BM), and rubber (RB), were screened with the compositions 51%, 29%, 9%, 4%, and 3%, respectively. Each USW sample was gasified using a thermogravimetric analyzer (TGA) coupled with mass spectrometry (MS) at the heating rates of 5, 10, and 15 ℃/min and a final process temperature of 900 ℃. Thermal weight loss (TG) curves exposed the degradation in the order HP > SP > RB > BM > PP. Derivative thermogravimetric (DTG) peaks revealed that HP, PP, BM, and SP were degraded in three temperature-oriented phases in the range 172–731 ℃. The RB took an additional phase in the range 584–660 ℃. Major released gases, H2, CH4, CO, and CO2, were detected using MS via mass-to-charge (m/z) ratios. Higher H2 and total gas yield produced in the case of the HP dominated other materials at the lower heating rate of 5 ℃/min. Validation of data was assessed by equating experimental and calculated curves; therefore, the regression coefficient (R2) ranged between 0.884 and 0.997. The kinetics of the process were estimated by applying the Flynn–Wall–Ozawa (FWO) model at the conversion rates (α) of 0.2, 0.5, and 0.8, which presented reasonable results. Overall, the lower heating rates supported higher thermal conversion and a high quantity of gaseous products for all the components. [ABSTRACT FROM AUTHOR]

Straw, which is characterized by its low cost, large quantity, and rich supply of biomass energy, is often converted into energy that can be utilized in industrial production through pyrolysis technology. This paper examines the pyrolysis experiments of four kinds of straw (rice, wheat, peanut, and corn) from the Henan Province of China, conducted in an air environment with varying temperature-rise rates. Based on the experimental results, an analysis was conducted on the effect of the rate of temperature rise on the degree of straw pyrolysis and the pyrolysis characteristics of each type of straw. The activation energies of the pyrolysis reactions were calculated utilizing the Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO), and Starink methods. It was concluded that the pyrolysis process of all four types of straw could roughly be classified into three stages: dehydration and drying stage, volatile release stage, and carbonization stage. Among the four types of straw evaluated, rice straw exhibited the most favorable combustion performance, while wheat straw demonstrated the best pyrolysis effect. Increasing the heating rate resulted in a pronounced thermal hysteresis effect during the straw's pyrolysis, as evidenced by the TG and DTG curves shifting toward higher temperatures. The reaction speed increased as the heating rate increased, and the amount of residual carbon displayed an upward trend. [ABSTRACT FROM AUTHOR]

Coal spontaneous combustion (CSC) is a major safety concern affecting not just miners and businesses, but of industry in China generally. Chemical methods are already widely applied in the field of CSC prevention and plays a vital role in suppressing its negative effects. Ionic liquids (ILs) are novel and environmentally friendly solvents that have shown possible inhibitory effects on CSC through controlling the reactive groups in coal's molecular structure. To study the effects of various ILs on CSC more thoroughly, this paper examined several types of IL that had been pre-treated for different periods and examined how they performed during different phases of the combustion process. A long flame coal type was selected and immersed in four ILs [BMIM][BF4], [BMIM][NO3], [BMIM][I], and [EMIM][BF4]. Immersion periods were 2 days, 3 months, and 6 months; a raw coal sample was retained as a control. LFA 457 laser-flash apparatus determined the thermophysical properties of the samples between 30 and 300 °C. The kinetic process of the samples (30–800 °C) was deduced by thermogravimetric–differential scanning calorimetry thermal at various heating rates (2, 5, 10, and 15 °C min−1), and the thermal effect parameters were obtained. Results from this paper show that immersion treatment using ILs has an inhibitory effect on CSC, and the reliability of the thermophysical parameters was verified by uncertainty analysis. The pre-treated samples characteristics and exothermic peak temperature with different degrees of hysteresis were recorded, and statistical analysis verified the conclusions from the thermal physics experiments. The pre-treated sample with the greatest lag over various stages was found, and the apparent activation energy (Ea) of its rapid oxidation stage was calculated by Flynn–Wall–Ozawa and Kissinger–Akahira–Sunose methods. Meanwhile, the two kinetic methods confirm each other and come to a conclusion after joint verification. The greatest Ea found here was for a 6-month immersion coal sample using the IL [BMIM][BF4]. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Shared‐energy storage (SES) can break the energy interaction barrier between the demand side and the supply side, which is becoming an option for improving the flexibility of energy systems. This study designed a novel structure for the shared‐energy aggregator (SEA), incorporating a microgrid (MG), prosumer and SES. Then, a two‐level market transaction optimization model for SEA, considering the robust stochastic optimization method, is proposed; namely, at the day‐ahead stage, a robust stochastic operation optimization model is constructed to achieve the dispatching plan from the demand side under the objective of achieving the minimum energy consumption cost for the prosumer, and at the real‐time market stage, a robust stochastic operation optimization model from the supply side is constructed to arrange the optimal dispatching strategy under the objective of the maximum aggregator benefits of MG and SES. Finally, an industrial park micro‐grid in Qinghai Province, China, is selected as an example for analysis. [ABSTRACT FROM AUTHOR]

The transient rainfall infiltration and grid-based regional slope-stability (TRIGRS)-Scoops three-dimensional (3D) coupling model combines the influences of rainfall infiltration and 3D topography on slope safety. However, the Scoops 3D model defines the physical and mechanical parameters of underground materials with a uniform or layered method, which cannot describe the variability in the horizontal direction. To address this limitation, a method of creating a 3D distribution file of physical and mechanical parameters for underground materials was proposed. This method was applied to a mountainous area in Chishang Town, China. Based on the TRIGRS-Scoops 3D coupling model, the stability of slopes in the study area was assessed under different rainfall conditions. The dangerous slopes were located where the proportion of unstable grids exceeded 1%. The TRIGRS-Scoops 3D coupling model was repeatedly used to determine the curve of the rainfall threshold for landslide activation. This curve is based on the intensity (I) and duration (D) of rainfall. The results show that the 3D distribution file can effectively reflect the variability of parameters in the horizontal direction. The landslide activating rainfall threshold curves for the 13 dangerous slopes in the study area exhibit a linear relationship between lgI and lgD. This study can reveal slope stability under different rainfall conditions and provide a theoretical basis for landslide warnings. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Because China has emerged as the largest greenhouse gas (GHG) emitter in total annual emissions, to accelerate the pace of GHG emission reduction in China is important to the success of global efforts in addressing climate change. Carbon trading is a market mechanism and key instrument in the mitigation of climate change. This paper explores the policy process and development state to date of China׳s carbon-trade market to understand the emergence and development of that market and to understand what barriers are hampering China׳s carbon-trade market development. To achieve this goal, this paper introduces and analyzes China׳s status in the international market, examines the factors driving carbon-market launching by the Chinese government, and traces the development of mandatory carbon-emission trading and voluntary emission trading. It is argued that China׳s carbon-trading market is confronted with challenges such as the absence of a functional carbon-trading market, inaccuracy of the quota allocation, an imperfect trading mechanism, and lagging legislation. At the present stage, shortcomings such as having no real-time carbon price and dominated spot transactions differentiate China׳s trade market substantially from a functional system. A quick market integration of China׳s carbon market appears remote. It is suggested that specific measures be taken to promote the development of the Chinese carbon-trading market. [ABSTRACT FROM AUTHOR]

• Polyhalite ore started to decompose into anhydrite and langbeinite at 573 K. • The changes of internal models of vibration of SO 4 indicated a phase transformation. • The most probable mechanism function matched D3 Janders diffusion mechanism. • Calcination and hot-leaching could improve the extraction of potassium. In this paper, the thermal decomposition of polyhalite ore from Dayantan Playa in Qaidam Basin of China was investigated by X-ray powder diffractometry (XRD), Raman spectroscopy (Raman), and thermal analysis techniques (TG-DTG). The dehydration reaction of polyhalite ore takes place with the release of water and starts at about 510 K. The results of X-ray diffraction of roasting sample showed that polyhalite ore starts to decompose into anhydrite and langbeinite at 573 K. Raman spectroscopy, in conjunction with X-ray diffraction, was also used to follow the thermal decomposition of polyhalite ore. The changes of internal models of vibration of the SO 4 ions in sulfates indicated the phase transformation polyhalite, langbeinite, and anhydrite. The reaction kinetics of thermal decomposition of polyhalite ore were successfully modeled by a Coats-Redfern equation (ln g (α) T 2 = ln A R β E 1 − 2 R T E − E R T ) and the activation energy is found to be 208 kJ·mol−1. Additionally, the effect of roasting temperature on potassium extraction from polyhalite ore was studied. [ABSTRACT FROM AUTHOR]

As the fourth-largest industry waste residue, after iron slag, steel slag, and red mud, in China, the comprehensive utilization of nickel slag is imminent. Coal-based reduction combined with magnetic separation was considered an efficient method to extract iron from nickel slag. During the coal-based reduction of Jinchuan ferronickel slag, the growth characteristics and kinetics of metallic iron were investigated in this paper. The metallisation rate and metal iron grain size gradually increased with the reduction temperature or the reaction time, and the coal-based reduction process was divided into the rapid formation period and the aggregation growth period of the metallic phase. The granularity distribution of metallic iron obeyed the Doseresp sigmoidal function, and the activation energy of grain growth at different stages were 52.482 ± 4.448 kJ·mol−1 and 26.426 ± 3.295 kJ·mol−1, respectively. Meanwhile, a mathematical growth model of the metallic iron grains was also established. [ABSTRACT FROM AUTHOR]

A sample from the Jurassic Tamulangou Fm. and two comparison samples from the Cretaceous Fm. were used to document the hydrocarbon generation kinetics and phase behaviors at two heating rates using the confined gold tube system. The results show that the different heating rates affect the reaction rates, paths and levels of organic matter evolution. The average activation energy and dominant frequency activation energy of liquid hydrocarbon are significantly lower than those of gaseous. Moreover, igneous intrusion had a positive effect on the blooming, enrichment and preservation of organic matter, promoting a Ro increase of 0.09%–1.07% in the Jurassic Tamulangou Fm. Two models were used to simulate the normal and abnormal evolution caused by thermal events combined hydrocarbon generation kinetic parameters. Thermal simulation analysis shows that oil generation was initially slow and then increased rapidly until a burial depth of 1500 m was reached at ~128 Ma. The largest hydrocarbon expulsion began at ~120 Ma, corresponding to a burial depth of 2450 m. The maximum cumulative yield is 510 mg/g TOC, and it is still in the peak period of hydrocarbon generation, which demonstrates a favorable potential for hydrocarbon exploration. [ABSTRACT FROM AUTHOR]

The Middle Permian Lucaogou Formation in Northwestern China mainly contains typical saline lacustrine oil shale. To study the differences in geochemistry and hydrocarbon generation of source-rock samples in Lucaogou Formation in Jimusaer Sag, 57 core samples from two boreholes were analyzed herein by performing total organic carbon (TOC) analysis, RockeEval pyrolysis, and gas chromatographicemass spectrometry experiments on saturated hydrocarbons. The kinetics of oil generation were studied using two samples comprising typical maceral components. The results showed that the hydrocarbons produced by telalginite are relatively rich in pristane (Pr), phytane (Ph), b-carotane, high-carbon normal alkanes, and C29 regular steranes. Hydrocarbons produced by lamalginite contain a significantly higher content of C20 tricyclic terpanes (TT), C21TT, C24 tetracyclic terpanes (TeT), C29 norhopane, and C28 regular sterane. Based on the pyrolysis and biomarker compound parameters, telalginite has a higher conversion rate for hydrocarbons than lamalginite in the low-mature to mature stage, which is consistent with their kinetic analysis. Lamalginite source rock displays a much narrower distribution of activation energies than telalginite source rocks. Such narrower activation energy distribution effectively narrows the main stage of hydrocarbon generation. In addition, the activation energy distribution of lamalginite concentrated in the high-value interval, indicating the characteristics of the relatively lagging hydrocarbon generation of lamalginite. [ABSTRACT FROM AUTHOR]

• Morphology, nanostructure, functional group composition, and oxidation reaction of soot particles with different fuels are analyzed. • Soot particles from WCO biodiesel combustion exhibit more disordered nanostructure. • The surface functional group content and sp3/sp2 of biodiesel soot particles are higher. • Soot particles from WCO biodiesel is easier to be oxidized than fossil diesel soot particles. • The nanostructure definite correlations with soot particles reactivity. Biodiesel is one of carbon neutral fuels for diesel engine and waste cooking oil (WCO) would be the most viable source for biodiesel production in China. This paper studied the micromorphology, nanostructure, surface functional group composition, and oxidation activity characteristics of particles emitted from a China V bus fueled by pure WCO biodiesel and petroleum diesel, respectively. Compared with petroleum diesel, the results showed that particle mass (PM) and particle number (PN) of WCO biodiesel decreased by 38.66% and 38.12%, respectively, while the proportion of nucleation mode particles increased by about 10%. The soot particles of WCO biodiesel have higher disordered nanostructure, smaller primary particle size and fringe length, larger fringe separation distance and tortuosity, and lower graphitization degree than those of petroleum diesel. Moreover, the oxygen-containing surface functional groups content and carbon atom hybrid ratio of soot particles of WCO biodiesel were higher than those of petroleum diesel under the same oxidation temperature. And then the activation energy of soot particles from WCO biodiesel which contained more lattice defect structures was 38.43 kJ/mol, 37.8% lower than petroleum diesel, which is easier to be oxidized. [ABSTRACT FROM AUTHOR]

Glass-ceramics acquired from the melting of rocks have a vast application marketplace. In this study, an olivine basalt rock from Zhangjiakou in China was selected as a raw material to prepare basalt glass-ceramics, and the crystallization kinetics of olivine basalt glass was investigated using differential thermal analysis. Polarizing microscope and X-ray diffraction (XRD) analysis results revealed that the main mineral compositions of olivine basalt are plagioclase, pyroxene, olivine, and iron oxide(s). Three crystallization peaks were observed in the DSC curve of the olivine basalt glass. The Avrami exponent (n), apparent activation energies for the crystallization, and glass transition of basalt glass were determined using the Owaza method based on data obtained from isothermal measurements. The crystallization activation energies (E) of the three crystallization peaks of olivine basalt glass were 314.20 kJ/mol, 1232.49 kJ/mol, and 696.89 kJ/mol, respectively. In addition to this, the crystal growth index indicated that the crystallization mode in the olivine basalt glass was surface crystallization. The crystallization phases and microstructure of the olivine basalt glass heated at 860 °C, 1100 °C, and 1180 °C were also studied. The conclusions obtained offer some useful information for the preparation of basalt glass-ceramics from olivine basalt rocks. [ABSTRACT FROM AUTHOR]

China Low Activation Martensitic (CLAM) steel is selected as the candidate structural material in Fusion Design Study (FDS) series fusion reactor conceptual designs. The creep property of CLAM steel has been studied in this paper. Creep tests have been carried out at 823 K and 873 K over a stress range of 150–230 MPa. The creep curves showed three creep regimes, primary creep, steady-state creep and tertiary creep. The relationship between minimum creep rate ( ε ̇ min ) and the applied stress ( σ ) could be described by Norton power law, and the stress exponent n was decreased with the increase of the creep temperature. The creep mechanism was analyzed with the fractographes of the rupture specimens which were examined by scanning electron microscopy (SEM). The coarsening of precipitates observed with transmission electron microscope (TEM) indicated the microstructural degradation after creep test. [ABSTRACT FROM AUTHOR]

The iron aluminide coating on China Low Activation Martensitic (CLAM) steel was prepared by pack cementation and subsequent heat treatment. A surface Fe 2 Al 5 layer was formed on CLAM substrate by pack cementation process with Fe 2 Al 5 donor powder and NH 4 Cl activator. Diffusion heat treatment was performed in order to allow the phase transformation from Fe 2 Al 5 to a phase with lower aluminum content. Morphology and composition of the coatings were characterized by optical microscopy (OM), scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS), glow discharge optical emission spectroscopy (GDOES) and X-ray diffraction (XRD). There is a need to study the interdiffusion behaviors in these Al containing systems, as a basis for controlling the formation and subsequent degradation of the coating. In this paper, a predictive model was developed to describe the phase transformation of Fe 2 Al 5 as a function of processing parameters. The Wagner’s equation was used to calculate the interdiffusion coefficients based on the analysis of the Al concentration profiles. The results showed that the interdiffusion coefficients in the FeAl and α-Fe(Al) phase strongly depends on Al content and showed a maximum at about 28 at.% Al. [ABSTRACT FROM AUTHOR]

Natural gas and condensate derived from Carboniferous-Permian (C-P) coaly source rocks discovered in the Dagang Oilfield in the Bohai Bay Basin (east China) have important implications for the potential exploration of C-P coaly source rocks. This study analyzed the secondary, tertiary, and dynamic characteristics of hydrocarbon generation in order to predict the hydrocarbon potentials of different exploration areas in the Dagang Oilfield. The results indicated that C-P oil and gas were generated from coaly source rocks by secondary or tertiary hydrocarbon generation and characterized by notably different hydrocarbon products and generation dynamics. Secondary hydrocarbon generation was completed when the maturity reached vitrinite reflectance (Ro) of 0.7%–0.9% before uplift prior to the Eocene. Tertiary hydrocarbon generation from the source rocks was limited in deep buried sags in the Oligocene, where the products consisted of light oil and gas. The activation energies for secondary and tertiary hydrocarbon generation were 260–280 kJ/mol and 300–330 kJ/mol, respectively, indicating that each instance of hydrocarbon generation required higher temperature or deeper burial than the previous instance. Locations with secondary or tertiary hydrocarbon generation from C-P coaly source rocks were interpreted as potential oil and gas exploration regions. [ABSTRACT FROM AUTHOR]

• The AAEMs were selected as catalysts of oil shale to study the pyrolysis process. • The yield of shale oil and gas improved with the presence of AAEMs during pyrolysis. • The AAEMs promote the release of H 2 and reduce the precipitation of C 2 H 4 and C 2 H 6. • Na+ increases the relative content of alkanes in the shale oil and declines alkenes. • The catalysts of Na and Mg reduce the E values of oil shale during pyrolysis. Changji oil shale in Xinjiang Province of China is abundant and characterized by high ash content and low oil content. While, catalytic pyrolysis is an effective method to improve pyrolysis performance. In this paper, CH 3 COONa, (CH 3 COO) 2 Ca and MgO were selected as catalysts of oil shale to investigate the its pyrolysis behavior and pyrolysates characteristics. The results reveal that the three catalysts improve the yields of shale oil and gas. They also promote the release of H 2 and reduce the precipitation of C 2 H 4 and C 2 H 6 in the pyrolysis gas. And CH 3 COONa and MgO improve the formation of CH 4 , while, CH 3 COONa and (CH 3 COO) 2 Ca enhance the yield of CO. In addition, these catalysts have little influence on the component of the spent shale because of its high ash contents. The existence of CH 3 COONa increases the relative content of alkanes in the shale oil and declines the relative content of alkenes, while (CH 3 COO) 2 Ca and MgO play the opposite role. The presence of AAEMs cations increases H/C ratio and the relative content of short-chain aliphatic hydrocarbons in shale oil, making the shale oil lightened. The catalysts of CH 3 COONa and MgO reduce the activation energy of oil shale during pyrolysis. Because Na+ and Mg2+ as polar centers, change the electron cloud distribution of C C bond. The E values of CJ, CJ + Na and CJ + Ca during pyrolysis fluctuated with the entire conversion rates and CJ + Mg exhibited a constantly increasing trend. [ABSTRACT FROM AUTHOR]

Thermal aging experiment is an effective method to evaluate the thermostability of structure materials which serve in high temperatures. But it difficult to acquire the aging data throughout service term, because it would take a long time. Hence, an accelerating thermal aging model of China low activation martensitic (CLAM) steel was built in this paper to shorten the time of the thermal aging experiment. The microstructure analysis and Charpy impact tests were conducted on CLAM steel after thermal aging with different temperatures. The results showed that raising temperature could accelerate the grain coarsening process and the main factor of ductile-to-brittle transition temperature (DBTT) increasing was grain coarsening after aging for less than 8000 h which were analyzed by fracture model. Hence, the activation energy of grain coarsening with a value of 47.4 kJ/mol could be regarded as the activation energy of thermal aging. Then a model of accelerating thermal aging was built by using Arrhenius formula to evaluate the properties degradation during thermal aging. This strategy could be used to accelerate thermal aging process of CLAM steel through raising aging temperature and it could save time and cost for aging experiment. [ABSTRACT FROM AUTHOR]

To investigate the influencing mechanism of potassium on solid products of biomass torrefaction, peanut shell, a typical agricultural waste in China, was selected as the feedstock and the experiments were carried out in the holding temperature range of 200 ~ 300°C, and in the atmosphere of nitrogen. Based on the water-leaching and impregnation (K2CO3, KCl and K2SO4; impregnation concentration: 0.5%K, 1%K and 2%K) methods, the results showed that the solid product yield of WLPS (water leached peanut shell) torrefaction was higher than that of RPS (raw peanut shell) torrefaction at 200 ~ 300°C. And all these three potassium salts (K2CO3, KCl, and K2SO4) inhibited solid product yields of torrefaction. Potassium existing in RPS was not beneficial for upgrading the organic content during the torrefaction process. The carboxylate was the key intermediate during the biomass torrefaction conversion process. Besides, the activation energy of WLPS (106.28 kJ·mol−1) was higher than that of RPS (83.34 kJ·mol−1) during the torrefaction. The impregnated potassium salts reduced the activation energy of WLPS torrefaction process. However, the activation energy of potassium salt impregnated WLPS torrefaction was still higher than that of RPS. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the exhaustion and deterioration of coal resource, a lot of research has been focused on improving the combustion efficiency all over the world, especially in China, in recent years. In this study, several industrial waste slags, which can decrease the ignition temperature, including the gasification slag, deactivated methanol catalyst and furnace slag, are reused as catalysts to improve the combustion efficiency of high-sulfur coal. The kinetic analysis of combustion reaction using Coats-Redfern's model indicates that the industrial waste slags could efficiently reduce the activation energy of coal ignition. By comparing and analyzing the composition of the waste slags with TG-DTG, XRD and XRF, the efficiency of combustion-supporting of the waste slags was confirmed and optimized. • Three kinds of industrial waste slags are reused as catalysts of coal combustion. • The kinetic analysis indicates the activation energy of coal ignition reduces. • The combustion efficiency of high-sulfur coal can be improved by the waste slags. • Gasification slag is verified that the effect of combustion-supporting is the best. [ABSTRACT FROM AUTHOR]

In order to study the relationship between the chemical structure and pyrolysis products of oil shale, a series of experiments with Huadian oil shale of China were performed at various heating rates (10, 20 and 50 °C/min) by using Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy (TG-FTIR). The quantitative analysis of pyrolysis products, including CH4, CO, CO2, H2O and shale oil, was carried out. The results showed the temperature at which the evolution rate of pyrolysis products reached a peak value. Also, the evolution rate was found to increase with increasing heating rate. For the abovementioned pyrolysis products, the values of kinetic parameters such as activation energy (E) and pre-exponent factor (A) were between 183 and 270 kJ. mol-1 and from 3.3 × 109 to 2.8 × 1013 s-1, respectively. The Functional Group-Depolymerization Vaporization Crosslinking (FG-DVC) pyrolysis model based on the chemical structure of fuel was employed to simulate the evolution process of CH4, CO, CO2, H2O and shale oil at three different heating rates: 10, 20 and 50 °C/min. The simulation results were in good agreement with TG-FTIR experimental data, indicating the applicability of the FG-DVC model to modelling the pyrolysis process of oil shale. [ABSTRACT FROM AUTHOR]

Alpine wetlands are considered to be very sensitive to future climate warming. Understanding changes in decomposition rates ( Rs) of soil organic matter (SOM) and temperature sensitivity ( Q) in alpine wetlands, under the scenarios of a warming climate and decreasing soil moisture, is important for predicting their carbon (C) budget. Here, we established three sampling transects from wetland edge to meadow in the Zoige alpine wetlands in China, which represented the gradients of decreasing soil moisture. We conducted an incubation experiment (5-25 °C) to explore changes in Q with the degradation process from alpine wetland to alpine meadow. The results showed that temperature significantly influenced Rs in all locations. Rs first increased from site I to site IV and then decreased from site IV to site V. However, Q and activation energy ( E) showed no apparent trends with soil coming from sites along a moisture gradient. Overall, the Q values in the wetland (sites 1.50) were significantly lower than that of the meadow (1.83); similar trends were observed for E. In addition, E exhibited a negative logarithmic relationship with C quality indices in all locations, which suggested that the C quality-temperature hypothesis is applicable to both alpine wetlands and meadows. These findings provide a theoretical foundation for predicting the potential influences of warming climate on soil C turnover and storage in alpine wetlands. [ABSTRACT FROM AUTHOR]

Decomposition of soil organic matter (SOM) is sensitive to vegetation and climate change. Here, we investigated the influence of changes in forest types on the mineralization of soil carbon (C) and nitrogen (N), and their temperature sensitivity (Q10) and coupling relationships by using a laboratory soil incubation experiments. We sampled soils from four forest types, namely, a primary Quercus liaotungensis forest (QL), Larix principis-rupprechtii plantation (LP), Pinus tabulaeformis plantation (PT), and secondary shrub forest (SS) in temperate northern China. The results showed that soil C and N mineralization differed significantly among forest types. Soil C and N mineralization were closely coupled in all plots, and C5N ratios of mineralized SOM ranged from 2.54 to 4.12. Forest type significantly influenced the Q10 values of soil C and Nmineralization. The activation energy (Ea) of soil C and Nmineralization was negatively related to the SOM quality index in all forest types. The reverse relationships suggested that the carbon quality-temperature (CQT) hypothesis was simultaneously applicable to soil C and N mineralization. Our findings show that the coupled relationships of soil C and N mineralization can be affected by vegetation change. [ABSTRACT FROM AUTHOR]

The effects of high pressures on the yield and kinetics of gas generated by the cracking of crude oil were investigated in laboratory simulation experiments. Samples of a low-maturity non-marine oil were recovered from the Paleogene Shahejie Formation in the Dongying depression, Bohai Bay Basin, eastern China. The oils were cracked to gas under different pressure and temperature conditions in an autoclave. Initial temperatures of 300 °C were increased to 650 °C at rates of either 30 or 100 °C/h. Reaction products were analysed at the end of each 50 °C temperature increase. Pressure conditions were either 0.1 MPa (i.e. atmospheric) or 20 MPa. Results show that high pressures inhibit or delay oil-to-gas cracking and retard the initiation of the cracking process. The temperature at which oil was cracked and the activation energy of the formation of C1-5 hydrocarbons increased under high pressure conditions, demonstrating the effects of pressure on the kinetics of the oil-to-gas cracking process. High pressures and high temperatures inhibited the conversion of C2-5 hydrocarbons to methane during secondary cracking. In addition, high pressures retarded the generation of N2, H2 and CO during cracking of oil. The presence of water increased the yields of total cracked gas, C2-5 hydrocarbons and CO2 in high-pressure conditions. The simulation results show that CO2 and C2-5 hydrocarbons have similar yields during oil-to-gas cracking. Using the kinetic parameters determined from the laboratory experiments, the yield and production rate of gas generated during the cracking of oil from Member 4 of the Paleogene Shahejie Formation in the Minfeng-Lijin sag (Dongying depression) were calculated. The results indicate that only limited volumes of natural gas in this area were derived from the cracking of oil, and that most of the gas was derived from the thermal decomposition of kerogen. [ABSTRACT FROM AUTHOR]

The large amount of boron-bearing iron tailings in China is a resource for metals that needs to be more completely and efficiently utilized. In this evaluation, the ammonium sulfate roasting process was used to make a controllable phase transformation to facilitate the subsequent extraction of valuable metals from boron-bearing iron tailings. The effects of roasting temperature, roasting time, the molar ratio of ammonium sulfate to tailings, and the particle size on the extraction of elements were investigated. The orthogonal experimental design of experiments was used to determine the optimal processing conditions. XRD (X-Ray Diffractomer), scanning electron microscope (SEM), and simultaneous DSC–TG analyzer were used to assist in elucidating the mechanism of ammonium sulfate roasting. The experimental results showed that nearly all Fe, Al, and Mg were extracted under the following conditions: (1) the molar ratio of ammonium sulfate to iron tailings was 3:1; (2) the roasting temperature was 450 °C; (3) the roasting time was 120 min.; and, (4) the particle size was less than 80 μm. The kinetics analysis indicated that the sulfation of metals was controlled by internal diffusion, with the apparent activation energies of 17.10 kJ·mol−1, 17.85 kJ·mol−1, 19.79 kJ·mol−1, and 29.71 kJ·mol−1 for Fe, Al, Mg, and B, respectively. [ABSTRACT FROM AUTHOR]