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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]

To investigate pore structure, free radical concentrations, thermal behavior and FTIR micro-characteristics of the re-oxidation coal, we used Scanning Electron Microscope (SEM), Electron Spin Resonance (ESR), Fourier Transform Infrared Spectroscopy (FTIR), and a Synchronous Thermal Analyzer (STA). We conclude that the extension of pores and micropores on the coal surface due to initial oxidation, lead to an increase in the combination of coal and O 2 in the re-oxidation of coal (ROC). Moreover, as the initial degree of oxidation increases, the number of aliphatic hydrocarbons and hydroxyl groups show a decreasing trend, while the content of oxygen-containing functional groups (–COO–, C O, COOH) and free radical concentrations increase significantly. Differences between the aliphatic hydrocarbon content in raw coal, 80°C-Y coal (i.e., coal pre-oxidized at 80°C for 30 min) and 180°C-Y coal are small. However, the content of aliphatic hydrocarbons in 280°C-Y coal decreased sharply from 35.26% to 25.83% compared to that of 180 °C-Y coal. The free radical concentrations of the 380°C-Y coal increased by 9.84% compared to the raw coal. The initial oxidation can directly increase the free radical concentrations of coal, and promote the oxidation reaction of the re-oxidation coal. The consumption of combustibles during initial oxidation results in the rate of ROC being slower than the oxidation of raw coal. With the increase in the degree of initial oxidation, these changes become more obvious. [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 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]

In order to study damage deformation of low permeability and soft coal under pulsating water pressure, the experiment of different maximal pulsating water pressure acting on standard raw coal was done by using the RLW-2000M coal rheometer controlled by microcomputer. The results show that the strain curve can be characterized by three phases when the samples are damaged by pulsating pore-pressure. In the initial stage, that is compaction coupling phase, the strain curve will generate large deformation in the process of loading and unloading, so the hysteresis loop curve will not be formed. In the elastic coupling phase, the strain curve demonstrats a stable hysteresis loop curve. In the yield deformation phase, coal will generate fatigue failure after several large deformation. The deformation state of elastic coupling phase was determined by using energy dissipation, and the results show that the coal unit produces plastic deformation and damage after a cycle of pulsating water pressure. At last, on the basis of Logistic equation, the mathematical model of coal damage was established and the unknown parameters were calculated by fitting analysis. [ABSTRACT FROM AUTHOR]

To analyze the oxidation kinetics reason that self-ignition tendency of coal with different metamorphic degree are different, based on the basic assumptions of coal adiabatic self-heating process, a oxidation kinetics analysis on the reaction characteristics of the process was made combined with the Arrhenius equation, then this paper studied four feature parameters: adiabatic process apparent activation energy (Ec), the critical temperature ( Tc) and the average heating rates each stages of the adiabatic process, (Rhm,Rjs), finally, the relationship between each characteristic parameter and coal metamorphic level was made by numerical fitting. It is show that the oxidation kinetics characteristics are characterized by the four parameters (Ec, Tc, Rhm and Rjs) in the difficulty degree of coal self-ignition reaction (Ec),the difficulty degree of control ( Tc) and the heating speed (Rhm and Rjs) ;with the increase of coal metamorphic grade, Ec has a logarithmic relation with it, Tc has a linear relation, however, Rhm and Rjs have a negative exponent relation. The difference of self-ignition tendency of coal with different metamorphic degree is studied on oxidation kinetics, and it is of great significance to self-ignition control. [ABSTRACT FROM AUTHOR]

To investigate the characteristics of adiabatic oxidation phase and build the prediction model of coal spontaneous combustion critical point, the adiabatic oxidation experiment data of eight coal samples are given in this paper, based on the adiabatic oxidation experiment, element analysis experiment and industrial analysis experiment. The phase heating rates of adiabatic oxidation of these samples are also calculated. Then using the thermodynamic parameter calculation method, Tr0.05 and TΔmax are defined and obtained. Furthermore, based on the Levenberg-Marquardt method, the relationship between the coal element content, volatility, the phase heating rate of adiabatic oxidation and Tr0.05 are established. The results show that the content of N or S correlates positively with Tr0.05 Osand that O, C, or H content correlates negatively with Tr0.05. However, the link between these elements and stage-heating rate is the opposite. The law also suggests that stage-heating rate will be much faster and coal spontaneous combustion will be easier when Tr0.05 becomes much lower. The more volatile coal is, the lower Tr0.05, and the more likely it is to spontaneously combust. [ABSTRACT FROM AUTHOR]

Aiming at the problems of buried tube nitrogen injection that the nitrogen injection spot with intervals in the space causes the failure of continuous nitrogen distribution in goaf, leading to poor inert effect. In addition, the unrecycling of the nitrogen injection pipe causes great resources waste. Based on the principle that the shear capacity of the mining nitrogen injection pipe is superior to its tensile strength, new fire nitrogen injection process (rotating traction and non-interval) was designed, fundamentally solving major defects of buried pipe nitrogen injection, which can realize the synchronous movement between nitrogen injection point and the workface. According to the relevant principles of planar problems in elastic mechanics, the calculation method about dynamic parameter of non-interval nitrogen injection process for fire control was put forward. By using a geotechnical engineering numerical simulation software, the stress distribution of the nitrogen injection pipe in the goaf of Yanzishan Mine was simulated, and the traction power was computed based on it. [ABSTRACT FROM AUTHOR]

In order to theoretically understand the law of temperature rise due to spontaneous combustion in caving zone of roof coal in coal mine roadway, and identify the location of hazardous region and studied the fire prevention effects by nitrogen injection, the software FLUENT was used to solve the stable state of air leakage speed and oxygen concentration ,dynamic temperature distribution and cooling effects brought by nitrogen injection in the high caving zone based on the assumption that coal oxidation rate accords with Arrhenius law. The computation results indicate that the temperature rise reflects a slow-accelerating process and the portion close to roadway has lowest temperature while the deep portion comes next, the top temperature region lies in the middle part of caving zone and deviates to inlet. The rate of temperature rise in high temperature region accelerates both by the increasing air velocity in roadway and increasing porosity when practical size is kept unchanged. The nitrogen injection in high temperature region can lead to obvious cooling effects for the reason that the temperature close to injection hole decreases dramaticlly after short time and cooling effects extend towards part of the middle and outlet gradually. [ABSTRACT FROM AUTHOR]

Hypervascularity has been considered as one of the major features of many solid tumors. Green tea is one of the commonly drink resources in China, and its active component, Epigallocatechin gallate (EGCG), exhibits antiangiogenic activities in various experimental tumor models. However, EGCG has many shortages, e.g., relatively unstable, low lipid solubility, poor bioavailability, and short duration of action. To overcome the shortages of EGCG for antiangiogenic antitumor usage, our study developed a novel EGCG derivate, Y 6 (5,3′,4′,3″,4″,5″-6-0-ethyl-EGCG). The underlying mechanism was also elucidated. we evaluated the effects of EGCG, Y 6 on HCC and angiogenesis in vivo and in vitro. Moreover, to understand their antitumor mechanisms, key factors within angiogenesis-related signaling pathways (MAPK/ERK1/2, PI3K/AKT, HIF-1 VEGF) were analyzed by using western blot, immunohistochemistry (IHC), quantitative real-time quantitative PCR (RT-PCR). HepG2 xenograft model and the chorioallantoic membrane (CAM) were used to investigate the effects of Y 6 and EGCG on tumors and anti-angiogenesis in vivo. Micro-vessel density (MVD) was analyzed by IHC of CD34 staining. IHC, qRT-PCR and Western blot were used to detect the expression of HIF-1α and VEGF protein in tumor tissues. The protein levels of MAPK/ERK1/2, PI3K/AKT, HIF-1α, and VEGF in tumor tissues were detected by western blot. Our results demonstrated that both EGCG and Y 6 displayed antiangiogenetic and antitumor effects against HCC cells in vitro and in vivo. We found that rather than equal amount of EGCG, Y 6 displayed better abilities in inhibiting the growth of HCC tumor cells, as well as inhibiting the growth of neovascularization in the chick embryos and HepG2 xenograft tumors bearing-mice, based on the data obtained from MTT assay, immunohistochemistry (IHC), chick chorioallantoic membrane (CAM) assays. In the comparison of equivalent dose of EGCG, qRT-PCR data showed that Y 6 induced more significant decrease of the mRNA levels of HIF-1α and VEGF in supernatant-treated SMMC-7721 cells under hypoxic condition, as well as in the in xenograft tumor tissues; whereas Y 6 also significantly reduced the protein levels of MAPK/ERK1/2, PI3K/AKT, HIF-1α, and VEGF to a greater extent than EGCG, determined by western blotting assay. our work suggests that the new EGCG derivate Y 6 could significantly inhibit tumor growth and angiogenesis which is possibly involved with the signaling intervention of MAPK/ERK1/2 and PI3K/AKT/HIF-1α/VEGF pathways, and is supposed to be a potential therapeutic reagent for anti-angiogenesis treatment of solid tumors. Different concentrations of Y6 and EGCG group compared with the control group, the inhibition of chorioallantoic membrane (CAM) angiogenesis was significant. It indicated that it is a potential new vascular inhibitor, which may be a new treatment option for anti-angiogenic therapy in solid tumors. Image 1 [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]

The influence of emulsified oil, suspended solids, Fe, Fe, cationic water clarifier and sulfate-reducing (SR) bacteria on the aggregation behavior of residual hydrophobic modified polyacrylamide in treated oily wastewater from polymer flooding was studied by fluorescence spectroscopy and dynamic light scattering. The result of I /I showed that the polarity of hydrophobic microdomains increased, whereas the size of the hydrophobic microdomains may be decreased, where the value of I /I represents the ratio of the intensity of peak I (374.0 nm) to that of peak I (385.0 nm) of the vibration fine structure of pyrene monomer emission in residual polymer solution. The results of the ratio of I at 48 h to I at 0 h ( I /I ) indicated that oil and cationic water clarifier could inhibit the aggregation to some extent, while Fe and suspended solids were helpful for aggregation, and Fe and SR bacteria had no significant influence on the aggregation of polymer. [ABSTRACT FROM AUTHOR]

Introduction: Saponin of Schizocapsa plantaginea Hance I (SSPH I), a novel bioactive phytochemical isolated from the rhizomes of Schizocapsa plantaginea, has been demonstrated to exhibit anti-cancer activity against various tumors in preclinical studies. However, the molecular mechanisms involved in the suppression of hepatocellular carcinoma (HCC) are poorly understood. The present study aimed at analyzing the effects of SSPH I on autophagy and apoptosis in vitro. Methods: MTT and colony forming assays were used to detect cell viability and cell proliferation. Hoechst 33,258 staining and flow cytometry were used to determine apoptosis and ROS production. The apoptosis and autophagy-related protein expression levels were evaluated via Western blot assay. Characteristics of autophagy and apoptosis were observed by transmission electron microscopy. Lysosomal activity was stained with Lyso-Tracker Red and Magic Red Cathepsin B. Results: The results showed that SSPH I exhibited potent anti-cancer activity and proliferation in HepG2 and BEL-7402 cells and inhibited HepG2 cells through inhibiting autophagy and promoting apoptosis. The mechanistic study indicated that the inhibition of autophagy of SSPH I was mediated by blocking autophagosome–lysosome fusion. Additionally, we found that SSPH I could mediate the activation of MAPK/ERK1/2 signaling pathway, and the use of NAC (ROS inhibitor) and U0126 (MEK1/2 inhibitor) converted the effect of SSPH I on apoptosis and autophagy in HepG2 cells. Conclusion: These data suggest that SSPH I induces tumor cells apoptosis and reduces autophagy in vitro by inducing ROS and activating MAPK/ERK1/2 signaling pathway, indicating that SSPH I might be a novel agent for the treatment of HCC. [ABSTRACT FROM AUTHOR]

Abstract: A model was developed using remote sensing and geographic information system technologies for habitat identification of Oncomelania hupensis, the intermediate host snail of Schistosoma japonicum, in the Poyang Lake area, China. In a first step, two multi-temporal Landsat TM 5 satellite images, one from the wet and the second from the dry season, were visually classified into different land-use types. Next, the normalized difference vegetation index was extracted from the images and the tasseled-cap transformation was employed to derive the wetness feature. Our model predicted an estimated 709km2 of the marshlands in Poyang Lake as potential habitats for O. hupensis. Near-ground temperature measurements in April and August yielded a range of 22.8–24.2°C, and pH values of 6.0–8.5 were derived from existing records. Both climatic features represent suitable breeding conditions for the snails. Preliminary validation of the model at 10 sites around Poyang Lake revealed an excellent accuracy for predicting the presence of O. hupensis. We used the predicted snail habitats as centroids and established buffer zones around them. Villages with an overall prevalence of S. japonicum below 3% were located more than 1200m away from the centroids. Furthermore, a gradient of high-to-low prevalence was observed with increasing distance from the centroids. In conclusion, the model holds promise for identifying high risk areas of schistosomiasis japonica and may become an important tool for the ongoing national schistosomiasis control programme. The model is of particular relevance for schistosome-affected regions that lack accurate surveillance capabilities and are large enough to be detected at most commercially available remote sensing scales. [Copyright &y& Elsevier]

Green tea is the most ancient and popular beverage worldwide and its main constituent epigallocatechin-3-gallate (EGCG) has a potential role in the management of cancer through the modulation of cell signaling pathways. However, EGCG is frangible to oxidation and exhibits low lipid solubility and bioavailability, and we synthesized a derivative of EGCG in an attempt to overcome these limitations. The anthracycline antibiotic daunorubicin (DNR) is a potent anticancer agent. However, its severe cardiotoxic limits its clinical efficacy. Human carbonyl reductase 1 (CBR1) is one of the most effective human reductases for producing hydroxyl metabolites and thus may be involved in increasing the cardiotoxicity and decreasing the antineoplastic effect of anthracycline antibiotics. Accordingly, in this study, we investigated the co-therapeutic effect of Y6, a novel and potent adjuvant obtained by optimization of the structure of EGCG. The cellular concentrations of DNR and its metabolite DNRol were measured by HPLC to determine the effects of EGCG and Y6 on the inhibition of DNRol formation. The cytotoxic effects of EGCG and Y6 were tested by MTT assay in order to identify non-toxic concentrations of them. To understand their antitumor and cardioprotective mechanisms, hypoxia-inducible factor-1α (HIF-1α) and CBR1 protein expression was measured via Western blotting and immunohistochemical staining while gene expression was analyzed using RT-PCR. Moreover, PI3K/AKT and MEK/ERK signaling pathways were analyzed via Western blotting. HepG2 xenograft model was used to detect the effects of EGCG and Y6 on the antitumor activity and cardiotoxicity of DNR in vivo. Finally, to obtain further insight into the interactions of Y6 and EGCG with HIF-1α and CBR1, we performed a molecular modeling. Y6(10 μg/ml or 55 mg/kg) decreased the expression of HIF-1α and CBR1 at both the mRNA and protein levels during combined drug therapy in vitro as well as in vivo , thereby inhibiting formation of the metabolite DNRol from DNR, with the mechanisms being related to PI3K/AKT and MEK/ERK signaling inhibition. In a human carcinoma xenograft model established with subcutaneous HepG2 cells, Y6(55 mg/kg) enhanced the antitumor effect and reduced the cardiotoxicity of DNR more effectively than EGCG(40 mg/kg). Y6 has the ability to inhibit CBR1 expression through the coordinate inhibition of PI3K/AKT and MEK/ERK signaling, then synergistically enhances the antitumor effect and reduces the cardiotoxicity of DNR. Image 1 [ABSTRACT FROM AUTHOR]