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The Ni/C-SiO2 series catalysts were prepared by the method of soybean oil grinding, and were applied in the CH4-CO2 reforming reactions. These catalysts were characterized by the XRD, TG-DTG, BET, H2-TPR, CO2-TPD and chemical properties of the catalysts were measured by the fixed bed continuous reactions. The results showed that the nickel elements in the catalyst were fully transformed into Ni0 after calcining in inert atmosphere N2 for catalyst precursor prepared by grinding method, thus realizing the preparation of the mesoporous Ni-based catalysts by one-step of the calcination and the reduction. There were two types of carbon on the catalyst after the CH4-CO2 reforming reactions, one was the residual carbon source in the prepared catalyst, and another causing catalyst deactivation was the carbon deposition produced in the process of the reforming reaction. The influences of the promoters, such as CeO2, ZrO2 and La2O3 on the catalyst properties were investigated. The results indicated that the particle diameter of the Ni0 in the Ni-CeO2/C-SiO2, Ni-ZrO2/C-SiO2 and Ni-La2O3/C-SiO2 catalysts was decreased, the reaction activity of the Ni-CeO2/C-SiO2 and Ni-La2O3/C-SiO2 catalysts was enhanced, and the carbon deposition on the Ni-ZrO2/C-SiO2 and Ni-La2O3/C-SiO2 was reduced after the reaction compared to these of the Ni/C-SiO2 catalyst. The promoter La2O3 not only improved the activity of the catalyst, but also reduced the amount of the carbon deposition on the catalyst. The total carbon conversion reached 52% for the CH4-CO2 reforming reaction using the Ni-La2O3/C-SiO2 catalyst. [ABSTRACT FROM AUTHOR]

Difengjiang Jasmine Garden of Fuzhou was chosen as the study site. Methane, nitrous oxide and carbon dioxide production were in the control, and shell, gypsum, slag, biochar and straw addition treatments were determined by experiment incubation-gas chromatogram method. The results showed ： During the whole observation period, averaged methane production were 0. 014，0. 012，0. 012，0. 012，0. 013，0. 014 μg/(g • d), respectively. All addition treatment were decreased by 16. 7%, 16.7%, 15. 2k，7. 25%，2. 17% comparison with the control，respectively. Averaged nitrous oxide production were 0.008，0.014，0.030，0.015，0.009，0.019 μg/(g • d)，respectively. All addition treatments were not decreased nitrous oxide production comparison with that of the control, respectively. Averaged carbon dioxide production were 58. 7，79.5，86.5，51.0，44.7，1050 μg/( g • d), respectively. Slag, biochar addition treatment were decreased by 13. 1%，23. 8% comparing with the control, respectively. Shell, gypsum addition inhibited the jasmine soil methane production. Slag, biochar addition inhibited the jasmine soil methane and carbon dioxide production, however, all addition could not inhibit the jasmine soil nitrous oxide production. [ABSTRACT FROM AUTHOR]

Effects of the availability of nitrate nitrogen and different carbon sources on N20 and C02 emission from soil of typical farmland in the North China were studied. The static culture systems were adopted in an indoor experiment. The results illustrated that, compared with single nitrate nitrogen fertilizer, combined different carbon sources and nitrate nitrogen fertilizer increased the emission of N20 from soil, except for cellulose; combined different carbon sources and nitrate nitrogen fertilizer increased the accumulated emission of C02 from soil. The emission flux of N20 by treatment of pectin peaked 1 383.42 μg N ·kg-1 ·d-1 on day l.The emission flux of C02 by treatment of glucose peaked 370.13 mg C ·kg-1 ·d-1 on day 1, and the accumulated emission of C02 order was：glucose>pectin>straw>cellulose>starch>lignin. It showed a highly signifcant positive conrelation between the content of N〇2-N and emission of N20. Overall, combined cellulose and nitrate nitrogen fertilizer suppressed the N20 emission, improved the C02 emission, and increased NO3-N content; combined other carbon sources and nitrate nitrogen fertilizer promoted the N20 and C02 emission. [ABSTRACT FROM AUTHOR]

CO2-ECBM technology in deep coal seam is that CO2 can replace more CH4 and be buried in a long-term because of its strong adsorption effect. Experimental analysis in northern Shizhuang shows that the CO2 adsorption capacity is two times of CH4. With desorption pressure decrease, CH4 has higher desorption speed than CO2 so that it can be displaced effectively. CO2 injection causes the change of the physical property of coal reservoir, mainly refers to permeability variation caused by matrix shrinkage and swelling during CO2 adsorption and desorption, and the permeability decreases at first and increases rapidly with the decrease of pressure. By applying the permeability change rule, the geological model and numerical model were established. The influences of CO2 injection quantity, frequency and injection mode on the yield, recovery ratio and CO2 burial of the well group or single well were analyzed. The simulation results show that the gas recovery increases after two years CO2 injection with the injection rules such as the injection rate of 10-15 tons per day, continuous injection for 90 days, closing well for 90 days. Field test indicates that the CO2 adsorption capacity of No.3 coal seam is 8 tons/day.The group well burial potential is about 12 616 t. [ABSTRACT FROM AUTHOR]

In order to research the influence of carbon dioxide and ultra-fine water mist on methane explosion in limit space, a semi-confined transparent chamber was designed with the size of 120mm×120mm×840mm, and the explosion suppression experiment about the effect of different aerosol ratio carbon dioxide and ultra-fine water mist on stoichiometric methane-air premixed mixture was studied. The experimental results show that: the explosion suppression effect of the combine of carbon dioxide and ultra-fine water mist was better than it of any inhibitor alone. Under a certain volume fraction of carbon dioxide, explosion overpressure, pressure rise rate and explosion flame propagation velocity obviously decreased with the increase of volume content of the ultra-fine water mist. When singly adding 2% carbon dioxide or 1.4mL ultra-fine water mist, the sum of overpressure peak value decrement of the two conditions was 72.3mbar; when adding them together, the overpressure peak value decrement was 97.95mbar. The results indicate that the synergistic effect of carbon dioxide and ultra-fine water mist on methane explosion is exist. [ABSTRACT FROM AUTHOR]

Microwave co-pyrolysis of coal and circulating gas is a new technology to convert and utilize coal cleanly and effectively. In order to further understand the action mechanism of each single component in circulating gas, the effect of microwave power, pyrolysis time, gas flow rate and particle size of coal samples on the yield and composition of microwave pyrolysis products of low rank coal were studied by the microwave co-pyrolysis experiment under carbon dioxide atmosphere. The results indicate that carbon dioxide promotes the microwave pyrolysis of low rank coal to accelerate the decomposition of organic matters and generate much more volatile of raw coal, thus make the effective enrichment of minerals in blue-coke. The yields of the blue-coke and liquid products (coal tar and pyrolysis water) from microwave pyrolysis products are up to 60.8% and 21.8% respectively, and the valuable components content of gas (CO + CH4 + H2) is up to 54.03% when the optimal process conditions with the microwave power of 960 W, pyrolysis time of 40 min, carbon dioxide flow rate of 0.56 L/min and coal samples particle size of 5-10 mm are selected. The content of fixed carbon is up to 84.89% to meet Blue-coke Standard FC-4 Grade, volatile content is up to 4.86% to meet Blue-coke Standard V-1 Grade. The content of alkane compounds is up to 35.5%. [ABSTRACT FROM AUTHOR]

Concentration of O2 and CO2 has a great effect on storage quality of cold stored fruits or vegetables. Obtaining concentration variation and distribution characteristics of O2 and CO2 concentration in a controlled atmosphere storage (CA storage) can provide theoretical basis for optimal design and operation of CA storages. Hence, a combination of CFD calculation and experimental study were carried out to study the complicated phenomenon of air flow, heat and mass transfer in CA storage. An unsteady, 3D (three-dimensional) global CFD model was established for a real CA storage for apples in Xian. The CFD model includes k-ε turbulent model and species transport model. The apple zone was regarded as porous medium zone. Air cooler was equipped in the storage. User-Defined-Function (UDF) programs were developed in C language to achieve the variation of apples' respiration rate and mass fractions of gas species at the velocity-inlet boundary along with the local O2 and CO2 concentration in the CA storage. The mass transfer phenomenon for the reduction process of O2 concentration was numerically studied. The calculated concentration variation of O2 and CO2 were validated by experimental results. The experimental system consisted of a gas probe, gas analyzer and accessory measuring device. The gas probe was set inside the gas zone of the CA storage and connected to a gas analyzer at test room, where the piece of gas from the probe was measured and analyzed in every two hours. The numerical results were compared with the experimental data for whole reduction process of O2 concentration, including the reduction process of O2 concentration when N2 generator was working followed by the reduction process due to apples' aerobic respiration when N2 generator was stopped. The numerical results from the displacement process of O2 by inputting N2 indicated that the concentration of O2 in gas zone decreased in an exponential function, which was validated by experimental results with a deviation of 0.027. The numerical results from the following reduction process due to apples' aerobic respiration were validated with the average differences of 3.06% for O2 and 16.2% for CO2 concentration. Moreover, increasing N2 concentration of N2 generator would shorten the reduction process of O2. In the case of studied CA storage, O2 concentration decreased faster in gas zone than in apple zone in the beginning 4.1 h, but appeared the opposite characteristic afterwards. Concentration of CO2 increased similarly in gas zone and in apple zone. Concentration of CO2 decreased gradually with time. The concentrations of O2 and CO2 in gas zone appeared to be relatively uniform, but there existed concentration gradients in apple zone. The proposed 3D unsteady model can be used to get the reasonable reduction time of O2 concentration for CA storage, which would provide a valuable reference for choosing reasonable N2 generator. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) is one of the important raw materials for photosynthesis of crops in greenhouse, which can increase the harvest of the crops. In order to analyze the performance of CO2 fertilizer enrichment, this paper took indoor environment of greenhouse as the research object, and by means of unstructured mesh generation method, a two-dimensional turbulence computational model of greenhouse was built by ICEM CFD (the integrated computer engineering and manufacturing code for computational fluid dynamics) technique. After building 7532 triangle/quadrangle meshes, the skewness of mesh model was less than 0.75. To solve two-dimensional computational model of greenhouse, the CFD software FLUENT and the SIMPLE algorithm were used. Meanwhile, the porous model, the DO (discrete ordinates) model and the k-ε model were adopted. Governing equations of finite volume method were employed, including mass, momentum and energy conservation equations. In computational model, CO2 enriching inlet was set with the condition of mass flow inlet while outlet was set with the condition of pressure outlet through pre-calculation. And crop area was defined as porous material with the porosity of 0.8. Adopting steady-state solver to operate, environmental parameters such as indoor temperature, nitrogen (N2) concentration, oxygen (O2) concentration and CO2 concentration should be initialized when flow field of greenhouse was stable. Then transient solver was needed to numerical simulation when acceleration of gravity was 9.8 m/s2 and step size was 0.01 s. By such methods, the effects of CO2 jetting height, enriching flow speed and other factors on CO2 enrichment property were computed while the change of CO2 concentration and distribution regularities were studied. After the simulations, some results were obtained. CO2 enrichment process had little effect on temperature of crop area, and both temperature distribution and air velocity distribution of crop area were uniform. As CO2 enrichment process lasted only for 5 min and solar radiation affected indoor environment of the greenhouse rarely, the temperature difference in the crop area was less than 0.5°C. On the other hand, cooler air was more likely to deposit to the bottom of the greenhouse and hotter air exhausted from wet curtain because of density difference of air flow. With the influence of buoyancy lift and newly added flow, air velocity of bottom side was higher. And the biggest velocity of air flow appeared in the area between jetting nozzle and bottom side of the greenhouse. Molar mass of CO2 is greater than O2 and N2. And as a result of deposition effect of CO2, the bottom of the greenhouse had a higher CO2 concentration while CO2 concentration in upper part was less, which helped the photosynthesis of crops. Moreover, CO2 flowed to the exit of the greenhouse via bottom side. In crop area, CO2 concentration was higher when closing to entrance. Although there was nearly no different in first 30 s, CO2 jetting height had a certain effect on CO2 enrichment time. CO2 concentration could be decreased when CO2 jetting height was located at a high level. When jetting height was higher, spreading range of CO2 was larger, CO2 deposited in crop area was less and CO2 concentration was lower. However, CO2 concentration of crop area would be increased too fast when jetting height was too low. With the increase of CO2 enrichment flow, CO2 concentration increased and CO2 enrichment time decreased. CO2 enrichment flow had a certain effect on CO2 enrichment time in crop area. Thus, transforming enrichment flow or time could control CO2 concentration of the greenhouse which benefited photosynthesis of crops. A test was made to verify the accuracy of the numerical model. The simulation values and test values of CO2 concentration at the same moment were in good agreement, and the biggest difference between them was less than 5%, which demonstrated that such models were correct. Result of this paper reveals the CO2 enrichment rules and the characteristics of flow field in greenhouse, which has a certain reference for the design and optimization of CO2 enriching equipments in greenhouse. [ABSTRACT FROM AUTHOR]

Taking on Sihe Mine in Jincheng mining area as the research object，the mineral components and filling ways in coal were conducted by scanning electron microscopy and X-ray diffraction. According to the coal reservoir geometry model and percolation theory，the mathematical model about the initial permeability of coal and the permeability after reaction with mineral were established. Based on pore size distribution and the different mineral solubility of coal samples in Sihe Mine，the variation rules about permeability after injection carbon dioxide reactions with different minerals in coal were discussed. The results show that minerals in coal are mainly composed of clay and carbonate minerals；minerals in coal exists in two ways，namely some minerals adhere to fracture and completely fill or half fill in the coal fracture. The differences about reaction time among different minerals lead that coal reservoir permeability is increased first then decreased after injection carbon dioxide. When the contents of the minerals are the same，the higher of filling mineral contents in the large hole and cracks，the more increase of coal reservoir permeability after the dissolution of mineral；the experimental results verify the reliability of the mathematical model. [ABSTRACT FROM AUTHOR]

In this manuscript, effects of a new smash ridging tillage on micro-environment was studied. There were three treatments as followed: smash ridging tillage FL1 (20~30 cm), smash ridging tillage FL2 (30~40 cm), and rotation tillage CK (12~16 cm), respectively. The results showed that there were great effects of smash ridging tillage (FL1 and FL2) on wheat group canopy temperature, wheat group ground temperature and wheat group carbon dioxide content during wheat filling stage, while there were little effects at other growing stages. At wheat filling stage, wheat group canopy temperature of smash ridging tillage FL1 (31.72 ℃) and FL2 (32.15 ℃) were lower than that of CK (32.72 ℃), and carbon dioxide content of smash ridging tillage FL1 (373.5 mg·L-1) and FL2 (373.5 mg·L-1) were significantly (P≤0.05) higher than that of CK (431.7 mg·L-1); however, wheat group ground temperature of smash ridging tillage FL1 (27.98 ℃) and FL2 (28.30 ℃) were higher than that of CK (27.97 ℃). Furthermore, the relativity humidity of wheat group of FL1 and FL2 at pregnant stage and filling stage were 58.1%, 60.9% and 60.8%, 56.6%, respectively, and they were all higher than that of CK (52.7% and 57.7%). On the contrary, wheat group temperature of FL1 and FL2 at pregnant stage and filling stage were 25.0 ℃, 23.9 ℃ and 32.7 ℃, 33.2 ℃, respectively, and they were lower than that of CK (27.0 ℃ and 33.8 ℃). Additionally, there were about 1~2 ℃ lower and 0~0.5 ℃ higher of soil tillage layers of smashing tillage compared with CK at elongation and pregnant stage, respectively. Smash ridging tillage could effectively improve the micro-environment during the wheat middle and later growth stages, enhance wheat's adversity ability, and obtain higher grain yields. [ABSTRACT FROM AUTHOR]

In winter of 2011, kobresia humilis meadow was dealt under different grazing intensity on the Qinghai-Tibet plateau. From May to October in 2012, this study used infrared analyzer (Li-6400) with a transparent chamber to measure NEE, Reco and GPP under different grazing intensity. The results showed that (i) NEE, Reco and GPP had obvious inter-monthly variation. The varying curve of NEE looked as U-shaped, varying curve of Reco and GPP acted as a single peak value wave. (ii) Grazing had great impact on NEE, Reco and GPP, NEE was promoted to reach maximum value in advance by grazing. (iii) Under moderate grazing treatment, NEE and GPP had the highest value, which was the most suitable choice to absorb more carbon dioxide for alpine meadow ecosystem on the Qinghai-Tibet plateau. [ABSTRACT FROM AUTHOR]

The combustion of carbon-based materials in a high speed stream of dissociated air is analyzed, together with the oxidation mechanism from reaction rate controlled regime through the transition to diffusion controlled oxidation. The product of the heterogeneous reaction of carbon with oxygen is known to be CO and CO2, and CO2 is generally usually neglected when surface temperature is higher than 1000K in many literatures. However, we find that CO2 plays an important role in the whole oxidation processes, and can't be ignored through the three regimes. It is shown that two different platforms existed in the diffusion controlled regime. The first platform results from a reaction of the predominant CO2 product, and the other is due to the predominant CO product reaction. In fact, the concepts of "fast" reaction and "slow" reaction are not proper, since the two are the extreme cases of the general model we proposed. As surface temperature rises, the oxidation process will change automatically from nominated "fast" reaction to " slow" reaction. The dual platform theory has been confirmed by several experimental results. [ABSTRACT FROM AUTHOR]

Because of safety and minimally invasion, hysteroscopic surgery has gotten popularity and has become the routine for diagnostic and therapeutic interventions of intrauterine pathology. Advantages consist of short operating time, rapid postoperative recovery and low morbidity. However, during hysteroscopic surgery there are concerns about potential complications such as venous air and gas embolism. These are rare but hazardous complications, which can occur in all surgical procedures. In hysteroscopic surgery, large uterine veins may be exposed and are, therefore, entries for gas or air. A number of fatal cases have been described as case reports. Although awareness for air and gas embolism is raised this way, proper guidelines how to reduce the risk of venous gas or air embolism are lacking. The pathophysiologic difference between gas and air embolism is described herein because composition of the gases differs with their different physiologic effects. Signs and symptoms of patients are described, as early detection and intervention are crucial for survival. Furthermore, we provide guidelines for operating department personnel, surgeons, and anesthesiologists to reduce the risk of venous gas or air embolism during hysteroscopic procedures. Potential complications of these procedures may be prevented by this way. [ABSTRACT FROM AUTHOR]

Laparoscopic surgery has been controversial for a long time since it was applied to diagnosis and treatment of ovarian cancer. With the continual intensification of minimally invasive concept and development of minimally invasive surgical technology, laparoscopic staging surgery for ovarian cancer has been recognized and inthroned gradually in academia. Laparoscopic predictive model for optimal cytoreduction in advanced ovarian carcinoma is attracting widespread interest and active attempt. But there are continuous disputes on the feasibility, effectivity and safety of laparoscopic cytoreductive surgery. Clinical practice indicated that under the condition of well-selected cases and well-applied technology, lots of patients with advanced ovarian cancers can be benefited from minimally invasive surgical technology such as laparoscopy. Laparoscopic cytoreductive surgery for advanced ovarian carcinoma is worthy of further research. [ABSTRACT FROM AUTHOR]

Based on the excellent cooling characteristics of CO2 as a natural working substance and development prospects in the field of many hydrate technology, using the characteristics of pressure rising sharply under the phase equilibrium transition temperature of hydrate, through the innovation design of process, the carbon dioxide hydrate formation and decomposition alternate process is used to realize the pressurization system. Based on thermodynamic analysis of carbon dioxide level cascade refrigeration and combining with the phase equilibrium temperature, the experiment results show that the dynamics of 0.3wt% SDS additives is more advantageous to promote the formation of carbon dioxide hydrate in double-tube reactor compare with 4wt% THF thermodynamics additive. The synthesis time is 60 minutes at 1.4 MPa and -2 ℃. In SDS solution of 0.3wt%, lower temperature is more beneficial to the formation of hydrate, the critical temperature is close to -2 ℃. When it is lower than -2 ℃, the solution icing may block pipe. When the two sets of tube reactors are used alternately, the optimum cyclic temperature is as follows:the synthesis temperature is -2 ℃, the decomposition temperature is 10 ℃, and the shortest cycle time is 55 minutes. The carbon dioxide gas under high pressure is decomposed by condensation throttle to a low temperature of -36 ℃. [ABSTRACT FROM AUTHOR]

Dense phase carbon dioxide (DPCD) is a non-thermal processing technology, which affects microorganisms and enzymes through molecular effects of CO2 under pressures below 50 MPa and 60°C. DPCD has had less of a significant effect on the quality of food and has been applied to the process of meats, vegetables, seeds and food powders, fruits, spices and herbs, and fish. Currently, most of research are more focused on microorganisms and enzymes that are inactivated by DPCD. However, some research indicated that DPCD has an effect on the quality of meat and its products, mainly related to muscle pH value, color, water holding capacity, texture, etc. The nutritional composition of meat and its products also has a decisive effect on their qualities. Water is the highest content in meat and its products composition. Water can directly affect color, tenderness, juiciness, flavor, and the processing characteristics of meat and its products. Water content and its distribution showed dynamic changes in the processing and storage of meat and its products, which is an important factor in determining quality and shelf life. Litopenaeus vannamei is a favorite of consumers in aquatic products due to tender meat and high nutritional value. In our previous study, Litopenaeus vannamei was treated for sterilization and inactivation of polyphenol oxidase by DPCD. In order to further investigate the effect of DPCD on shrimp muscle quality, peeled shrimp were used as the studied object. The effects of temperature (35-55°C), pressure (5-25 MPa), and time (10-60 min) on nutritious components and water molecules of shrimp muscle were studied. The results showed as follows: when using the untreated peeled shrimp, the content of nutritious components (moisture, crude protein, crude fat, and ash), especially fat, significantly decreased (P<0.05) after DPCD treatment. With the increasing of DPCD treatment intensity, fat was extracted and water was dried out by DPCD. Partially ionized minerals and small molecular compounds containing nitrogen (e.g. free amino acids) were carried out with CO2 in the unloading process. While using the untreated peeled shrimp, the contents of myofibrillar and sarcoplasmic protein decreased significantly (P<0.05) and the content of insoluble protein increased significantly (P<0.05) with exposure to time, temperature, and pressure when DPCD was increasing. The reason for that was myofibrillar and sarcoplasmic protein were denatured and transformed to insoluble protein by DPCD. The results of low field nuclear magnetic resonance (LF-NMR) showed that peeled shrimp contained four kinds of water molecules with different mobility. With exposure to time, temperature, and pressure when DPCD was increasing, the degree of freedom of bound water increased while the degree of freedom of immobilized water and free water decreased. Nonetheless, the content of bound water and free water increased significantly (P<0.05) while the content of immobilized water decreased significantly (P<0.05), when the peeled shrimp was treated for 30 min at 15 MPa and 55°C of DPCD. Microorganism and PPO from Litopenaeus vannamei were inactivated, but the content of moisture, crude protein, crude fat, and ash decreased by 7%°、 C3%°C、 25%, and 11%, respectively. Sarcoplasmic and myofibrillar protein were denatured, and the free water ratio increased significantly (P<0.05). The research results will provide a reference for the application of DPCD in shrimp processing. [ABSTRACT FROM AUTHOR]

Objective To observe whether the carbon dioxide (CO2) concentration in the cleaning operating room for conducting laparoscopic operation monitored by the infrared-red ray detector conforming to the national standard. Methods Sixty cases of laparoscopic operation and non-laparoscopic operation completed in our hospital from January 1, 2014 to March 30, 2016 were selected as the research subjects. The 30 working days were selected (labeled serial number of 1 ,2 ,3...30) for conducting the laparoscopic operation (laparoscopic group, 30 cases)and the non-laparoscopic operation (non-laparoscopic group, 30 cases), which were conducted in the cleaning operation room. The CO2 concentration served as the observation indicator and the CO2 concentrations of operation room air in the laparoscopic operation and the non-laparoscopic operation were respectively detected at different time periods (7 time periods including postoperative 1 ,2 ,3 ,4 ,5 ,6 h and over 6 h). Their change condition was performed the comparative analysis. Results In the cleaning operating room, different degrees of exceeding standard phenomena existed in the laparoscopic operation group air at different time periods; the CO2 concentration in the non-laparoscopic operation group did not appear the exceeding standard. The CO2 concentrations at various time periods had difference between the laparoscopic group and non-laparoscopic group (P<0.05)； the total mean value in the laparoscopic group had differences among various time periods ( F =2.636 , P =0.037 ). Conclusion The CO2 concentration in the cleaning operating room of CO2 pneumoperitoneum for laparoscopic operation exceeds the standard, the corresponding departments should formulating the measures to clean the CO2 concentration in the laparoscopic operation room. [ABSTRACT FROM AUTHOR]

Under multiple gas sources environment, the quality of natural gas and substituted natural gas is quite complex. In order to ensure the safety of long distance pipeline and the natural gas metering accuracy, the gas quality of conventional, unconventional natural gas and substituted natural gas is discussed. The gas quality control demanded in multiple gas sources environment is summarized. In order to formulate the national standard of quality requirements for all kinds of gas entering long-distance transmission pipe networks, the control limits were discussed to find out the limits which including the concentration of total sulfur, hydrogen sulfide, carbon dioxide, carbon monoxide, hydrogen, oxygen, particles, and water content/water dew point. These parameters are fully discussed. [ABSTRACT FROM AUTHOR]

The Chinese solar greenhouse, characterized by east-west orientation, a transparent camber south roof, and a solid north roof and east and west walls, is utilized primarily in horticulture in northern China. This design of greenhouse can keep the sheltering plants from freezing in winter because of the "greenhouse effect". However, the healthy growing of plants still needs assisted heating especially during winter nights. The coal-fired heating system (CFHs) and the natural gas-fired heating system (GFHs) both have been widely applied to heat greenhouses. However, the conventional fossil energy sources, such as coal and natural gas, are non-renewable and are the major greenhouse gas (GHG) contributors. The overusing of fossil fuel in agricultural production has been directly or indirectly related to the global climate change, environmental pollution, and energy crisis. Therefore, renewable and clean energy, such as solar, geothermal, and shallow geothermal has been increasingly applied for greenhouse heating or cooling across the world. Ground source heat pump (GSHP) technology has dual functions in heating and cooling. It is one of the most rapidly growing green technologies for heating and air-conditioning in recent years. The GSHP application for solar greenhouse heating has proven to have a high primary energy ratio or coefficient of performance (COP) in previously studies. However, the environmental performance of the GSHP in heating solar greenhouse, such as its carbon footprint, is still unknown. Systematic and long-term study of the specific GSHP greenhouse-heating was required to evaluate its carbon footprint based on life cycle assessment (LCA) method. The GSHP in a Chinese solar greenhouse was studied to evaluate its environmental performance in greenhouse heating. The environmental performance of the GSHP was analyzed based on the field test data and the performance analysis models that were developed in this study. According to the study, in a 480 m2 Chinese solar greenhouse during the winter heating period, the GSHP demonstrated stable heating effects. The shallow geothermal energy utilized by the GSHP, in the processes of energy storage, extraction, enhancement of refrigeration compression cycles, and greenhouse heating, were studied to analyze the greenhouse gas (GHG) emission inventory and emission levels based on per square meter of the greenhouse floor. An analysis method based on LCA was developed for estimating the carbon footprint of Chinese solar greenhouse heating with GSHPs in this study, the carbon footprints of a GSHP greenhouse heating system operating on coal fired power and gas fired power were analyzed and calculated according to the data collected from a solar greenhouse heated in the Beijing area. Meanwhile, the variation of global warming potential (GWP, CO2 emission equivalent or CO2-eq) of GSHP in heating a Chinese solar greenhouse from 20 to 100 a were analyzed. The GWP of GSHP greenhouse heating operating on coal fired power and gas fired power were 257 g/(m2•d) and 72 g/(m2•d). Meanwhile, the total GWP of 100a is reduced by 1.6% and 5.4% from the calculation of 20 a. Comparing the carbon footprints between solar greenhouse heating with GSHP and Venlo greenhouse heating with natural gas, the carbon footprint of solar greenhouse GSHP heating was 39% more than that of Venlo greenhouse heating when GSHPs was operating on coal fired power, but the carbon footprint of solar greenhouse heating will be only 41% of Venlo greenhouse heating when GSHPs were operating on gas fired power. The GSHP heating test was focused on a Chinese solar greenhouse in this study to estimate the environmental performance; however, the carbon footprint calculation and analysis methods are applicable to different styles of multi-span greenhouse GSHP heating analysis. [ABSTRACT FROM AUTHOR]

In order to study the capacity of CO2 storage in coal bed and the displacement of methane CH4 in coal by CO2 injection, an experiment about the CO2 adsorption and coalbed methane ( CBM) replacement in coal under given pressure was carried out with coal specimens of large size (100 mm x100 mm x 200 mm) from the No. 3 coal seam, Qinshui Basin, China. Based on the experiment, the CO2 storage capacity difference between coal containing CH4 and coal without CH4 was contrastively analyzed. The experimental results demonstrate that, the storage of CO2 in the coal specimen can amount to 11. 03 L under the in-situ stress condition of the coal bed and injection pressure of 0. 5 MPa. CO2 permeability through the coal decreases with the increase of its adsorption amount during the experiment duration of 180 min. When the CO2 injection pressure increases to 1. 0 MPa from 0. 5 MPa under the same confining stresses, the CO2 storage amount in the coal increases by 93. 00%, the storage rate increases by 13. 50% and the amount of CH4 desorption increases by 18. 13%. It is found that the amount of CH4 desorption is larger than CO2 adsorption in the initial experimental stage. After that, the amount of CH4 desorption tends to be stable but far less than CO2 adsorption amount. Under the similar experimental condition, the CO2 storage capacity in coal containing CH4 is 59. 29% more than that of coal without CH4 and the storage rate in coal containing CH, increases by 12. 51% compared that in coal without CH4. [ABSTRACT FROM AUTHOR]

The influence of temperature on corrosion behavior of VM110SS casing steel in sour environment was studied in high temperature and high pressure autoclave by simulating the downhole environment of a gas field in Sichuan. The partial pressure of CO2, partial pressure of H2S and total pressure are 0.54 MPa, 0.41 MPa and 18 MPa respectively. The test temperature is from 30 °C to 150 °C. The relation between temperature and corrosion rate of the VM110SS steel can be obtained. The compositions and appearance of corrosion products were analyzed by SEM and EDS. The results showed that the corrosion rate of VM110SS increased firstly then decreased with the increase of test temperature. The maximum value appeared at 90 °C. The corrosion rate in gas phase was 0.838 mm/a, and the corrosion rate in liquid phase was 1.130 mm/a, which showed a extremely severe corrosion. Uniform corrosion characteristic was presented to specimens at all test temperatures and corrosion product was composed mainly of iron sulfides. The paper provides theoretical basis for casing corrosion mechanism at different temperature and guidance for casing steel selection. [ABSTRACT FROM AUTHOR]

In order to study effects of promoters on hydrate formation, adopting a self-designed hydrate reaction system, influences of the tetrahydrofuran (THF) and sodium dodecyl sulfate (SDS) on carbon dioxide hydrate formation were studied through experiments with constant temperature and volume. Hydrate formation rate, gas storage capacity and the apparent hydration number were calculated on the basis of real-time measurements of system temperature and pressure in the process of hydrate formation. The result showed that the suitable concentration of SDS can promote the dissolution of gas in the liquid phase, and improve the growth rate and gas storage density of hydrate. THF only had little effect on hydrate generation process. Compound additives SDS and THF working together could promote the hydrate formation importantly. [ABSTRACT FROM AUTHOR]

Three kinds of climate change simulation devices are used for study elevated CO2 concentration and air temperature increase: 1)Open system: Free Air CO2 Enrichment (FACE) with Infrared Heating(IH); 2)Half-open system: Open-Top Chamber (OTC); 3)Close system: Environment Chamber(EC). But the extremely high hardware and running cost of FACE and IH are the main restricts for their application. EC system cannot represent the really condition with large extent of crop growth environment change. Traditional OTC system with much lower cost has nearly the same growth condition for crop, but it is a passive temperature increasing system and has no CO2 addition. To well use the advantage of Half-open OTC technique for climate change simulation, we improved the traditional Open-Top Chamber (OTC) device by adding heating module, CO2 injection module and air exchange module. A hexagonal OTC was designed with 1.2m side length and 2.5m height, and the CO2 tank used for CO2 injection source and semiconductor sheet sealed for the heating system. Air heating and CO2 injection were automatically controlled when pumping outside air into OTC by fans to simulate the elevated air temperature and CO2 concentration scenario. We applied the improved OTC in early rice season, and the OTC was emplaced in the real rice paddy field without obstacle at the bottom for water supply. And air temperature, humidity and CO2 concentration were measured by every 2 min. The results showed that the difference of daily mean deviation of air temperature of the controlled OTC and the objective simulation temperature can be controlled less than ±0.2℃ with the largest difference of -0.58℃, and the controlled deviation of CO2 concentration was -39.4~4.8 μL/L. This research indicated that the improved OTC can be applied to simulate the elevated air temperature and CO2 concentration of the future climate change scenario. Meanwhile, the relative humidity in improved OTC is also showed that relative humidity (RH) nearly has no change without temperature increase, and would increase by 2% if air temperature increased. In a word, this improved OTC device can be used to simulate elevated CO2 concentration and air temperature of early rice for climate change simulation research. [ABSTRACT FROM AUTHOR]

Melatonin is an indole hormone produced by the pineal gland of mammals and humans. It can improve sleep, immune regulation, anti-oxidant and free radical scavenging, anti-tumor, lower blood pressure, regulate heart rate, protection of cardiovascular cells, kidneys, liver and other effects. Melatonin nutrient application in the food industry is greatly limited due to low solubility in water. When melatonin is made into liposomes, it's solubility in polar solvent is increased. However, the current preparing methods of melatonin liposomes are complicated, result in the low entrapment rate, high cost, and use too much organic solvent. From 1970s, supercritical fluids technology has been used in liposomal preparation because of its friendliness, nontoxicity to the environment and its solvent-free liposomes and industrial-scale of liposome production. Phospholipid, cholesterol and melatonin can be solvated by supercritical carbon dioxide concurrently with a certain proportion of ethanol under higher pressure. The liposomes can be obtained when the pressure is reduced to release CO2. The homogeneous super-critical solution is expanded and simultaneously mixed with the aqueous phase to yield liposomes encapsulating the lipid soluble drugs under the lower pressure. The experiment was conducted to enhance the bioavailability of melatonin by improving entrapment rate in this study. The response surface methodology was used to optimize the technical conditions of supercritical carbon dioxide method for the preparation of melatonin liposome. The entrapment rate of melatonin liposome as a major index was optimized based on the ethanol concentration, supercritical temperature and time by response surface methodology using single factor experiments. The applicability of the quadratic-multinomial-mathematical model developed based on the response surface methodology was verified. The results indicated that the highest entrapment rate of melatonin liposome was reached to 83.2% with the supercritical time of 35 min, the supercritical temperature of 50°C, ethanol concentration of 7.5%. Preparing melatonin liposome using supercritical CO2 method was able to be controlled in laboratory. This method is encouraged for promotion in industrial production due to its high entrapment rate, small particle and great stability. [ABSTRACT FROM AUTHOR]

Replacement of methane hydrate by CO2 is a new approach for the development of CH4, and the method can develop CH4 and store CO2 permanently. By optimizing design of experiment device, the influences on displacement efficiency of temperature and pressure in the system of quartz sand media are studied. The experiment results show that the replacement rates are 1.75%, 6.99%, 13.43%, 5.53%, 22.64%, 44.90% respectively, the corresponding replacement temperature are 273.15 K, 274.15 K, 275.15 K, 276.15 K, 277.15 K, 278.15 K, and the CO2 charge pressure is constant at 2.5 MPa. On the other hand, the replacement efficiency are 37.11%, 13.43%, 3.44%, 4.58% respectively, corresponding to the CO2 charge pressure at 2.0 MPa, 2.5 MPa, 3.0 MPa, 3.5 MPa and the replacement temperature being constant at 275.15 K. Therefore, temperature and pressure are driving force factors of CO2 replacement of CH4 hydrate reaction. [ABSTRACT FROM AUTHOR]

Injecting recovered CO2 from fuel gases into the reservoir crude oil at or near the condition of miscibility is one of the main methods to realize CO2 sequestration and utilization. Minimum miscibility pressure (MMP) is often considered as a key parameter for the design of a gas injection project. In this paper, the interfacial tension between CO2 and four kinds of reservoir crude oil were measured by the pendant drop method at stratum temperature, and the MMPs or the four kinds of reservoir crude oil were determined directly with visually observed miscibility appearance as 24. 12 MPa, 24. 81 MPa, 26. 87 MPa and 31. 69 MPa, respectively. At the same time, the polynomial extrapolation method was also used to determine their MMPs. The results showed that the error of MMPs determined by polynomial extrapolation method was within 3%, and corresponding to lower error value at higher MMP. It indicated that MMP determined by vanishing interfacial tension had the advances of low error and cost, convenience and easy operation. [ABSTRACT FROM AUTHOR]

It is important to remove the carbon dioxide produced by human metabolism in the limited confined space of some emergency or work during a long time rescue, such as refuge chamber or manned spacecraft. Compared with other absorbent, the sodium lime has more stable performance, more mature technology and more reasonable price, which is the irreplaceable advantage as an absorbent used for air purification in the confined space. Due to the special conditions ( such as interruption of power outside, volume restrictions and so on) after coal main disaster, the sodium lime is required to have higher adsorption efficiency and rate. In this paper, six kinds of sodium lime products were selected according to particle size, composition, adsorption efficiency and other conditions. According to the test that the sodium lime absorbing carbon dioxide under different composition, thickness, wind speed, temperature and humidity, the best recipe, the best work mode and best use conditions of soda lime were determined. The conclusion of this study provides the necessary data support and theoretical guidance to determine potassium superoxide medicine plate in confined spaces such as refuge chamber using conditions, optimizing the allocation, developing environment control and life support technology and equipment. [ABSTRACT FROM AUTHOR]

A comparative study on the reactivity of Shenmu char with CO2 and steam was conducted at the temperatures from 900 °C to 1 050 °C using isothermal thermogravimetric analysis method. To better understand the reaction activity of residual carbon, the homogeneous model, the shrinking un-reacted core model, the integrated model and the modification volumetric model were applied to correlate the relationship between reaction rate and carbon conversion at the late gasification stage. The results show that both the integrated model and the modification volumetric model have a better fitting accuracy. The fitting accuracies of the homogeneous model and the shrinking un-reacted core model change with the gasification temperatures and the agents. At the late stage, the ranges of the apparent activation energy of Shenmu char in the atmosphere of CO2 and steam are 200. 65-231.00 kJ/mol and 105.48-169. 10 k J/tool, respectively. The apparent activation energy calculated with the modification volumetric model is approximately 36 kJ/mol higher at the late stage than that at the early and middle stages. Shenmu coal char gasification was under chemical reaction control at the late stage within the experimental temperature range. [ABSTRACT FROM AUTHOR]

This paper investigated the effect of chemical properties of activated carbons (ACs) on SO2 removal activity. Carbons were characterized by various techniques including proximate and ultimate analysis, energy dispersive spectrometer(EDS) and CO/CO2 temperature programmed desorption (CO/CO2-TPD). Results show that the different chemical properties of ACs are derived from the different precursors. ACs produced from biomass precursors contain more carboxylic, phenol, carbonyl and quinone functional groups, while ACs from coal precursors mainly include ester, phenol, carbonyl and quinone groups. On the other hand, the different chemical properties have different impacts on SO2 removal activities. The CO2-forming groups such as carboxylic and ester over the surface suppress the SO2 adsorption capacity, while the effect of the CO-forming groups such as phenol, carbonyl and quinone is not obvious. The ash content of ACs also shows a correlation with the desulfurizing property of ACs, which results in some SO2 retained on the carbon surface after the desorption. [ABSTRACT FROM AUTHOR]

This study investigated the mass exchange mechanism of exploiting coal-bed methane by CO2 injection and the significance of carbon storage in coal strata. Also, a physical and mathematical model of exploiting methane by CO2 injection was developed. Gas collecting method by saturated salt solution was used for an experimental study on the relationship of mass transfer coefficients, which vary with the degree of coal metamorphism, the concentration and gas emission time. According to the analysis on experimental data, a positive correlation was found between α and concentration. With the same degree of coal metamorphism, the speed of α deduces over time, and the α speed reduction of CH4 is slower than that of CO2. With the same concentration level, a negative correlation was found between α and coal metamorphism. The α of CH4 is higher than that of CO2 with different metamorphisms, which means the adsorption capacity of CO2 is higher than that of CH4 with different metamorphisms. The CO2 injection not only increases the reservoir pressure, but also enhances the gas desorption displacement. The desorption amount of CH4 was more than that of CO2 has nothing to do with the coal metamorphic level. Therefore, the exploitation of coal-bed methane by gas injection and carbon dioxide storage is feasible in different metamorphic degrees of coal seam, even in the coal measure stratum. [ABSTRACT FROM AUTHOR]

With the global low carbon economy era commences, the reduction and utilization of greenhouse gas becomes a major concern in the world. The reclamation of greenhouse gas CO2 and the new opportunity it brings in the research area of carbon chemistry will become a new hot spot in the research frontier of green catalysis. In this paper, various typical catalytic reaction pathways for enabling direct conversion of CO2 to useful value-added chemicals were reviewed, including oxidation of saturated hydrocarbon by CO2, synthesis of organic acids and esters with CO2 Furthermore, some comments were made regarding the advantages and disadvantages of the catalysts involved, and their underlying reaction mechanisms of CO2 activation by catalysis. Based on these discussions, future work in this category was proposed. The authors believes that, the task-oriented activation of CO2 is the key factor governing the whole process of its chemical utilization, where suitable catalysts with high activity need to be developed, the exploitation of new reaction media and use of new phase state CO2 may greatly enhance the conversion and selectivity of the reaction and hence deserve further investigation, as to the direct use of CO2 emitted from different practical sources, it is quite necessary to develop multi-functional catalysts with desirable adsorption-catalysis activity, so as to meet the requirements from different cases, in addition, the investigation of photocatalysis of CO2, and the characterization and simulation on the process of photosynthesis are beneficial to both the utilization of new energy and the mitigation of greenhouse gas. [ABSTRACT FROM AUTHOR]

Pyrolysis experiments on low maturity asphalt from Sichuan Basin were carried out in a confined system, and the composition, yield and carbon isotopic composition of gas products were analyzed. Results show that there are large amounts of hydrocarbons gases generation from low maturity asphalt indicating that it is an important potential secondary organic material as Paleozoic shale gas source in Sichuan Basin. Yields of nitrogen (N2) in non-hydrocarbon gases generation from low maturity asphalt are generally high, but carbon dioxide (CO2) low. There is a carbon isotopic distribution with δ13C1 <δ13C2 <δ13C3 among different carbon number hydrocarbon gases. Simulation results were also applied for understanding genesis and accumulation of shale gases in geological environment. For example, low dry coefficient and light carbon isotopic composition likely indicate the well-closed geological conditions favorable for the accumulation of shale gases. High content of N2 is a potential indicator for its genesis and accumulation of shale gas. Effects of preservation conditions of gas generation on carbon isotope fractionation should be noted when the methane carbon isotope composition is used to identify the genesis of oil and gas including shale gas. [ABSTRACT FROM AUTHOR]

In order to determine the effect of inert gas (N2 and C02) on the process of methane premixed explosion in coal mine roadways, the detailed reaction mechanisms (include 53 mixtures, and 325 reactions) were investigated in this study. The mathematical model of methane explosion in the coal mine roadway was developed using the PREMIX code of CHEMKIN 3. 7 chemical kinetics packages. Through numerical computation, the change currents of reactant and free radical concentration, catastrophic gases generated from methane explosion and total consumption rate of methane were compared, due to the effect of N2 and CO2 on methane explosions, and the similarities and differences were also analyzed. The results show that CO2 is more effective than N2 in lowering the concentration of activation center during the reaction system and main catastrophic gases of CO and NO resulting from methane explosion. Therefore, it concludes that; CO2 is more effective than N2 in inhibiting methane explosion. [ABSTRACT FROM AUTHOR]

In order to eliminate the flammability hazard of residual propellant gas in the chamber, gas bottle filled with CO2 is equipped. The combustible gas content of the residual propellant gas is calculated by gas constitution model, and then the quantity range of CO2 to make the combustible mixed gas to an incombustible one is obtained through literary calculation. Considering the parameters of gas bottle used and other conditions in practice, the theoretical feasibility analysis and experimental verification of gas bottle filled with mass range of CO2 calculated are carried out, and the results show that the gas bottle with mass range of CO2 obtained can not only be opened and deflate completely, but also effectively eliminate the flammability of the residual gas. Meanwhile, the elimination effect of residual gas becomes more obvious With the increasing of the mass of CO2 added, which means the maximum quantity of CO2 calculated should be applied in practice. [ABSTRACT FROM AUTHOR]

The adsorption and desorption properties of carbon dioxide(CO2) on six activated carbons were investigated at 0,15,25,38 °C in an atmospheric dynamic adsorption reactor. The adsorbents were characterized by CO2 and N2 adsorption isotherms, FT-IR analysis and Boehm titration. The results show that micropore volume of activated carbons is an important factor to characterize the adsorption performance of CO2, the pore size distribution in the range of 0.5 -1. 0 nm or 2. 0-4. 5 nm trend to enhance the adsorption of CO2. The rate of adsorption or desorption increases with the increase of temperature. The adsorption capacity of CO2 increases with an increase of carboxyl and hydroxy groups on activated carbons. However, the increase of carbonyl groups would reduce the desorption capacity of CO2. [ABSTRACT FROM AUTHOR]

Huainan bituminous was pyrolyzed under different heating rates and the resultant chars were pressurized gasified under high temperature pressurized thermogravimetric analyzer (PTGA), then the kinetic parameters were also calculated. It is observed that the surface of rapid pyrolysis char (HN-RP) appears more loose and porous than that of the slow pyrolysis char (HN-SP); the stacking height of crystalline structure and radial spread dimension in char crystallites of the HN-SP are more intense than that of the HN-RP, resulting in a worse reaction reactivity; the concentration of oxygen surface complex C(O) increases with the increasing of pressure, they attach on the char surface and lead an improved char gasification reactivity; the overall gasification reaction formula can calculate the pressurized gasification kinetic parameters and in the dominating reaction range, the obtained correlation coefficients are all higher than 0.988; with the increase of pressure, the order of reaction n is liable to decrease. [ABSTRACT FROM AUTHOR]

In order to reveal NO formation characteristics and the effect of CO2 concentrated and CO on NO heterogeneous reduction with char during the process of O2/CO2 combustion, the combustion experiments for Shanxi lignite were carried out on a horizontal furnace. The results show that, compared with O2/N2 atmosphere, NO emissions from coal-nitrogen can be effectively suppressed in O2/CO2 combustion conditions. O2/CO2 atmosphere can inhibit converting volatile-nitrogen to NO remarkably, while the conversion of char-nitrogen to NO is relatively less restrained. The conversion of char-nitrogen to NO is significantly promoted with O2 concentration increasing. Char-NO heterogeneous reduction reaction is obviously improved by a moderate amount of CO2 and the promoting effect can be cancelled out to a certain extent by excess of CO2. The effect of CO addition on NO reduction is remarkable. The highest NO reduction efficient is reached when CO concentration is 0.5% ,however, continuing rising of CO concentration can weaken the effect of NO reduction. [ABSTRACT FROM AUTHOR]

In order to complete the construction of Changcun Coal Mine refuge haven, the research determined that the contents of multilevel oxygen supply system and principles of ground drilling system, mine pressure ventilation system, oxygen supply and purification equipment system according to theoretical analysis. The air supply volume of mine pressure ventilation system is 300 L/min after calculation according to temperature balance principle. The oxygen supply volume is 484 m³ in 96 hours for 100 people on the basis of oxygen amount per capita and space function. The air volume is 468 m³/h to absorb excess carbon dioxide according to the situation of carbon dioxide emission per capita. The pressure loss experiment of chemicals in purification equipment gains the conclusions that the faster wind, the more pressure loss and the pressure loss increases significantly when the wind speed overpasses 5 m/s. The deployment experiment gains the conclusion that the air supply and returning system can keep the refuge haven 160 Pa pressure difference inside. The research can provide scientific basis and experimental data for the construction of air supply system of refuge haven. [ABSTRACT FROM AUTHOR]

The four analytical methods of water content determination in natural gas, such as Laser method, capacitance method, fiber-optic method and quartz- crystal oscilation method, are worth promoting in natural gas industry due to simple operation and maintenance. These methods are about to be implemented as the standard to determine water content in natural gas in China. In order to guide the user of those methods to operate correctly, the comparison research about the operation Characteristics of the four methods are taken by experiment. There search content includes the factors of affect method accuracy, stability, and detecting speed. The research results show that the main factors affecting method accuracy are test temperature, pressure and gas flow, etc., and the accuracy of the fiber-optic method is also related to the carbon dioxide content. The capacitance method is poor in stability, so it needs for frequent calibration. As inadequate measurement time will produce in accurate measurement results, the appropriate measurement time of these methods should be determined by respective detecting speed. [ABSTRACT FROM AUTHOR]

Rotating-strip-port is wildly used in gas cookers at present. 15 gas cookers of this kind of port were selected to test the performance such as efficiency and emissions under 10 different gas components. Results showed that rotating-strip-port gave no much better performance than round--port-cooker, CO emissions usually were higher and tended to exceed standard with changing of gas components. However, the decrease of NOx emissions has are markable effect. [ABSTRACT FROM AUTHOR]

Replacing methane with CO in the hydrate structure, storing CO and producing methane from methane hydrate reservoirs have attracted much attention of the researchers worldwide. The effect soft pressure and temperature on replacement rate were investigated by measuring the change of the methane molar percentage in the gas phase. The test system was in pure water, and the replacement reaction lasted 50 hours. The experimental results show that the methane molar percentage in the gas phase at the end of replacement process is increased from the initial 1.56% to 39.74%, 41.89%, 45.45% and 48.04% respectively corresponding to the replacement temperature at 273.15K, 274.15K, 275.65K and 276.15K with the CO2 charge pressure at 2.5 MPa. On the other hand, the replacement rate respectively reach 44.87%, 45.45%, 46.66% and 47.21% corresponding to the CO2 charge pressure from 2.2 MPa to 2.5 MPa, 2.8 MPa, 3.1 MPa with the replacement temperature at 275.65K. Therefore, it is concluded that the influence of temperature and pressure on replacement rate is positively in some ranges, but not great. [ABSTRACT FROM AUTHOR]

The microwave-assisted heating apparatus was employed to study the reforming of CH4 with CO2 over activated carbon. The influences of microwave power and CH4/CO2 molar ratio on reforming reaction were investigated. Furthermore, catalytic activity of the activated carbon was tested. And specific surface area analysis and Bothem titration method were used to explore the possible reason for the deactivation of activated carbon. The results indicate that increasing microwave power or decreasing the CH4/CO2 molar ratio can result in an increase in the reactant gas conversions as well as in the content of syngas, together with a decrease in the molar ratio of H2 and CO. It is found that an encouraging catalytic activity is achieved at the beginning, followed by a sharp loss of catalytic activity after 40 min, which is mainly caused by the change of pore structure and the reduction of functional oxygen groups. [ABSTRACT FROM AUTHOR]

This paper analyzed production and consumption situation of fossil fuel in Sichuan province. It showed that fossil fuel in Sichuan suffered from insufficiency, low quality, difficult mining, contradiction between production -- consumption structure and energy storage structure, high intensity and low utilization in energy consumption and high carbon dioxide emission. Under the low -- carbon development with the consideration of economics and environment, the proposals for fossil fuel development in Sichuan province are put forward. [ABSTRACT FROM AUTHOR]

Using low temperature oxidation equipment of the coal and electron paramagnetic resonance (EPR), researched the variation of gas products and redical concentration of lignite, gas coal, gas-fat coal and anthracite at different low temperature oxidation temperature and opened out the laws of low-temperature oxidation of coal self-heating in such a way of the combination of macro and micro. The results show that the oxidized molecular side of the coal is broken that come into being CO gas, C2H4 gas and free radicals, and CO and C2H4 sign gas and free radicals concentration is being to increase with the increasing of the temperature; coal being oxidized to product the amount of CO gas and C2H4 gas and the concentration of free redicals that have a periodic law: the regenerative stage of low-temperature oxidation, CO gas is a small amount or does not appear, and free radical concentration has a small change; the stage of the thermal oxidation is to appear from the CO gas to C2H4 gas, CO formation with the oxidation temperature increases slowly, the concentration of free radicals increases gradually; the stage of the depth of oxidation is to appear C2H4 gas to H2 gas, the formation of CO and C2H4 have a rapid increase with the increase of oxidation temperature, free radical concentration increasing with the increase of oxidation temperature becomes smaller. [ABSTRACT FROM AUTHOR]

Based on the comprehensive analysis of the greenhouse gas emission constitution in open pit coal mine, the corresponding econometric model of carbon emission was established. The research indicates that the greenhouse gas sources of surface mine involves the indirect emission of power consumption, direct emission of fuel combustion and explosion, CH4spilling, the greenhouse gases spilling caused by spontaneous combustion of gangue and coal, reduction of carbon fixation caused by mining disturbance. Based on this finding, the calculation method of various carbon emission sources was given referring to IPCC Guidelines for National Greenhouse Gas Inventories, and the econometric model of carbon emission was established. Taking the case study of Buzhaoba Open Pit Coal Mine, calculating that emission of greenhouse gas in the open pit mine is 122 351.19 t in the year of 2008. [ABSTRACT FROM AUTHOR]

According to the application of new technologies such as chlorine adsorption and high--efficient biological treatment, the technical principles and technical characteristics of the catalytic reforming and alkaline residue treating process are analyzed. The new technologies applying in different units achieve obvious results, such as improving the gasoline octane number, reducing the harmful emission substances such as COD, phenol and H2S, improving the quality of sewage water. [ABSTRACT FROM AUTHOR]

The methods of experimental measurements and theoretical calculation are used to research the relationship of indoor CO2 concentration and building air tightness in natural ventilation and mechanical ventilation, respectively. Three experimental conditions of windows closed and opened are designed. The blower door test method is used to test natural ventilation, and the indoor CO2 concentration is tested. The general ventilation theoretical calculation formula is used to calculate the indoor CO2 concentration of mechanical ventilation conditions. The results show that the indoor CO2 concentration difference of windows opened and closed is about 20% in natural ventilation, and it is 10% in mechanical ventilation. [ABSTRACT FROM AUTHOR]

Corrosion failure of oil pipe was happened during the injection exploitation of high temperature multicomponent thermal fluid. The corrosion datum was analyzed by grey relational method. The results showed that water content and CO2 partial pressure had the most notable effect on the corrosion of oil pipe, and flow velocity, temperature and CO2 partial pressure had more remarkable effect. Aimed at the corrosion characteristics of oil pipe, the high temperature CO2 corrosion inhibitor with abrasion resistance should be chosen to reduce corrosion. [ABSTRACT FROM AUTHOR]

When the temperature is lower than triple point of natural gas, CO2 is likely to frost in the cryogenic natural gas liquefaction process. A precise prediction of CO2 frosting temperature in CH4 -- CO2 binary system will contribute to the study of CO2 removal from natural gas by sublimation. The calculation of CO2 frosting temperature in CH4-- CO2 binary sys-tem based on gas--solid phase equilibrium model was conducted by PR equation of state (EOS). The predicted value of PRE-OS, HYSYS simulator and Approximate Conditions of Solid CO2 Formation chart were compared with experimental data, the results showed that the three methods were in good agreement with experimental data. Furthermore, according to experimental data, a empirical function was proposed to predict the frosting temperature of CO2 in CH4 -- CO2 binary system for rough estimate. [ABSTRACT FROM AUTHOR]