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The electric power sector is the primary contributor to carbon emissions in China. Considering the context of dual carbon goals, this paper examines carbon emissions within China's electricity sector. The research utilizes the LMDI approach for methodological rigor. The results show that the cumulative contribution of economies scale, power consumption factors and energy structure are 114.91%, 85.17% and 0.94%, which contribute to the increase of carbon emissions, the cumulative contribution of power generation efficiency and ratio of power dissipation to generation factor are -19.15% and -0.01%, which promotes the carbon reduction. The decomposition analysis highlights the significant influence of economic scale on carbon emissions in the electricity industry, among the seven factors investigated. Meanwhile, STIRPAT model, Logistic model and GM(1,1) model are used to predict carbon emissions, the average relative error between actual carbon emissions and the predicted values are 0.23%, 8.72% and 7.05%, which indicates that STIRPAT model is more suitable for medium- to long-term predictions. Based on these findings, the paper proposes practical suggestions to reduce carbon emissions and achieve the dual carbon goals of the power industry. [ABSTRACT FROM AUTHOR]

Foam is used as an efficient means of dust suppression in underground coal mines. The poor performance of conventional adding device of foaming agent restricts its wide application. The objective of this study is to propose and investigate a new parallel jet adding device (PJAD). Experimental results show that PJAD requires a greater water flow to produce negative pressure than the single stage jet adding device (SJAD) and is harder to generate cavitation. PJAD consumes a less pressure loss than SJAD and realizes any adding proportion below 1%, which is especially suitable for precision addition of foaming agent. A foaming system used for dust suppression is put forward with PJAD adding foaming agent. Field application indicates that foam achieves a far better dust suppression effect than the roadheader water spraying, and the foam cost is significantly reduced due to the low adding proportion of foaming agent. The marked dust suppression effect makes us believe that the proposed PJAD will greatly promote the large-scale application of foam technology used for dust suppression in underground coal mines. [ABSTRACT FROM AUTHOR]

This paper analyses the carbon dioxide emissions caused by industrial energy consumption of Tianjin from 2005 to 2012. The carbon emissions decomposition illustrated that the scale of production factor played a major role in the growth of Tianjin industrial carbon emissions and the average contribution of carbon emissions is up to 220.8975% in the statistical period; the intensity of energy factor played an important role in slowing down the growth of industrial carbon dioxide emissions. The average contribution of carbon emissions was −136.1994% in the statistical period. The prediction model based on carbon emissions data from industrial energy consumption from 2003 to 2012 reached a high accuracy, with an average error of 1.78% for stochastic impacts by regression on population, affluence, and technology (STIRPAT) model, 2.41% for the Logistic regression model and an average error of 1.54% for the grey model. This research can contribute to predict the carbon emission and through it some suggestions can be made. [ABSTRACT FROM AUTHOR]

This paper had experiments on lignite and bituminous coal, respectively. The characteristic temperature points were obtained at the oxygen concentration of 5%?10%?15%?17%? 21% and 30% when the heating rate was 10K/min, respectively. The coal ignition decreased as oxygen concentration increased. Coats-Redfern integral formula was utilized to calculate the activation energy from ignition temperature to end temperature of the combustion. It revealed that the activation energy increased along with oxygen concentration increasing. And the activation energy of lignite was less than bituminous coal, and spontaneous combustion of lignite occurred more easily. For the same coal sample, TG curve drifted to the left with the increase of oxygen concentration. It indicated that within a certain range the increase of the oxygen concentration shorted the reaction time, the coal sample was more likely to catch fire. [ABSTRACT FROM AUTHOR]

The coal seam condition of test coal mines is low permeability, large dip angle, soft coal, and low gas drainage rate. This text researches hydraulic flushing as pressure relief and increased permeability measures. It adopts theory analysis, numerical simulation, and field testing to research key technology for hydraulic flushing. It combines previous studies of ?three-steps drainage method?, propose to gas comprehensive treatment measures. First, it studies coal breaking mechanisms of high-pressure water jets and confirms the water pressure of hydraulic flushing. Next, it adopts numerical simulation and field testing to study the scope of influence. Finally, it studies the gas treatment effect of gas comprehensive measures after the measures have been carried out. Studies show that the result of influence scope between numerical simulation and field tests are close. The final influence scope confirms at 4.5m. Adopting the inspection of the weight of washed coal, residual gas pressure, residual gas content verified the effectiveness of measures. These measures achieve the aim that gas drainage rate increases, quantity measures are reduced, engineering time is reduced, and safety and quickly eliminate the outburst danger of working face, The study guarantees safety production of similar coal seam condition as the test coal mine. [ABSTRACT FROM AUTHOR]

Coal seam spontaneous combustion has become one of the major reasons of coal mine accidents and disasters, which not only seriously threatens the safety mining, but also causes a waste of a great amount of coal resources. To solve the serious problem of residual coal spontaneous combusion in goaf, based on the engineering geological condition of working face, this text simulated stress, strain and plastic distribution of overlying strata in goaf by using FLAC3D numerical simulation software, and based on the nephogram of the stress, strain, plastic zone and change curve of monitoring point, the failure law of overlying strata is analyzed and combined numerical simulation results with empirical formulas, the horizontal and vertical "three zones" range and in goaf were calculated. And studies the law of three typical coal samples between the concentration of CO2, CO, CH4, C2H4 and coal sample temperature through programmed heating experiment. Based on the simulation and experimental results, determined the distribution range of "three zones" was determined, the index gas CO and auxiliary index gas C2H4 were chosen for predicting the coal spontaneous combustion, based on the research, it provided a scientific basis for predicting the residual coal spontaneous combustion and getting the minimum safe speed of advancing working face that will not cause the coal spontaneous combustion in goaf. [ABSTRACT FROM AUTHOR]

air-fuel equivalence ratio and timescales of kinetic reaction and oxygen transport were used to analyze the combustion of underground coal fires at different temperature stages. At high temperature stage, due to the fast rate of kinetic reaction, oxygen concentration transported from galleries or cracks was lower than that required by theoretical kinetic reaction. Thus the oxygen consumption rate of coal combustion was controlled by oxygen transport rate and the coal fires were incomplete combustion because of lean oxygen concentration. According to the Single-Particle Reaction- Diffusion model proposed by Krishnaswamy, a formula to estimate oxygen consumption rate of underground coal fires with lean oxygen concentration and incomplete combustion at high temperature was developed. A numerical case study was conducted to analyze and examine the proposed formula. The investigated results show that the proposed formula can effectively estimate oxygen consumption rale controlled by oxygen transport at high temperature. [ABSTRACT FROM AUTHOR]

To develop low consumption and an environmentally friendly degradation technology for organic pollutants, micro-SiC/graphene composite materials were synthesized by photocatalytic reduction, and the composition and morphology of the prepared materials were characterized by XRD, FTIR, Raman spectroscopy, XPS, and SEM. Rhodamine B (RhB) was selected as the simulated pollutant to investigate the photocatalytic activity and stability of composite materials under visible light irradiation. The degradation mechanism was preliminarily discussed by active species capture experiments. Results show that the lives of photogenerated electron and photogenerated hole of SiC were prolonged when combined with graphene, which improved the photocatalytic activity and stability of composite materials. The degradation efficiency of RhB reached 92.7% with the composite material of SiC/graphene ratio (1:0.8) under 60 min irradiation, and the degradation process accorded with the first-order reaction kinetic equation. The contribution of main active species for photocatalytic degradation followed with a decreasing order of photogenerated hole (h + ), superoxide anion radical (·O 2 - ), photogenerated electron (e - ), and hydroxyl radical (·OH).

Objective: To evaluate the transmission risk and features of schistosomiasis by analyzing the data concerning positive rates of anti-schistosome antibody using catalytic models., Methods: Cross-sectional survey was conducted in seven villages with different endemicity of schistosomiasis in Jiangxi (Caohui, Xinhua, Jingtou villages), Anhui (Yuye, Tieguai, Longshang villages) and Hubei (Hebei village) Provinces in 2008. Serum samples were collected and indirect hemagglutination assay was performed to detect anti-schistosome antibodies in serum. Antibody positive rate was calculated and differences among villages and age groups as well as between genders were analyzed. Data of antibody positive rate based on age strata for each village were analyzed by two-stage catalytic model and reversible and two-stage compound catalytic model. Parameters of each model were estimated through the maximum likelihood method. Seroconversion rate and sero-negative conversion rate were estimated in the two-stage catalytic model. Seroconversion rate, seroreversion rate and sero-negative conversion rate were estimated in reversible and two-stage compound catalytic model. The fitting effect was evaluated through correlation analysis and chi-square tests. The best fitted models and parameters were used to analyze the transmission risk and characteristics of schistosomiasis., Results: A total of 6 428 individuals were examined with an average schistosomiasis antibody positive rate of 39.80%（2 485/6 428）. In terms of age, the peak of antibody positive rate in Caohui, Xinhua, Jingtou, Yuye, Tieguai, Longshang, and Hebei villages occurred in the age group of 46-50 （82.86%, 58/70）, 31-35 （60.78%, 31/51）, 31-35 （68.42%, 26/38）, 41-45（55.04%, 71/129）, 51-55 （62.38%, 63/101）, 56-60 （31.43%, 33/105）, and 16-20 （21.88%, 7/32） years old, respectively. In general, the antibody positive rate showed a trend of increase followed by a decrease with increasing age in each village. The best model for the data of Caohui, Xinhua and Jingtou and Yuye village was the two-stage catalytic model. The estimated seroconversion rate in these villages was 0.049 5, 0.044 0, 0.055 7, and 0.034 4 respectively, all higher than the corresponding sero-negative conversion rate of 0.005 9, 0.019 6, 0.015 5, and 0.017 8. The best model for the data of Longshang, Tieguai and Hebei villages was the reversible and two-stage compound model. The seroconversion rate in these villages was 0.062 9, 0.168 1, and 0.039 4 respectively, the seroreversion rate was 0.168 8, 0.121 1, and 0.152 2, and the sero-negative conversion rate was 0.001 7, 0.000 2, and 0.090 9., Conclusions: The catalytic model based on antibody positive rate by age strata could reflect the transmission rate and risk quantitatively and may provide guidance for making control strategies.