The accurate determination of the gas in place in shale reservoirs is a basic but challenging issue for shale gas evaluation. Conventional canister gas desorption tests on retrieved core samples and subsequent data analyses (via linear or polynomial regression)—originally developed for coalbed methane, where gases are mainly stored in the adsorbed phase—is unadvisable for shale gas, which is stored as an appreciable amount of free gas in shale reservoirs. In the present study, a mathematical model that simultaneously takes into account gas expansion, adsorption/desorption, and the gas flow in shale is proposed to simulate gas release from a core sample retrieved from the Lower Silurian Longmaxi Formation of the Fuling shale gas field, Sichuan Basin. The results indicate that, compared with the value of 2.11 m3/t rock estimated with the traditional United States Bureau of Mines (USBM) method, the total gas in place within the studied Longmaxi Shale estimated with our mathematical model under reservoir pressure conditions is up to 5.88 m3/t rock, which is more consistent with the result from the new volumetric approach based on Ambrose et al. According to our mathematical model, the content of free gas is 4.11 m3/t rock at true “time zero”, which accounts for 69.9% of the total gas. On the other hand, the lost gas portion is determined to be up to 4.88 m3/t rock (~85% of the total gas). These results suggest that the majority of the free shale gas is actually trapped within the pore space of the shale formation.

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Basing on analysis of flame pictures given by visioscope by two-color method, the paper presents evolution of radiation heat transfer coefficient \(\varepsilon_s\) of soot in diffusion flames in air, in furnace and in combustion chamber of Diesel engine. \(\varepsilon_s\) reaches respectively its maximal value of 0.15; 0.30 and 0.45 in regions of maximal soot fraction of the three above flames.

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In the context of global adaptation to climate change, the demand for water, especially drinking water, becomes a serious issue that needs to be studied to find feasible and economical solutions. Many available technologies have been applied to produce drinking water such as filtration of groundwater or seawater. However, the implementation of these technologies is feasible or not depending on specific nature as well as socio-economic conditions. For the drought regions where there is no seawater and lack of groundwater, moisture separation technology becomes a feasible solution. A system to extract the water from moisture has been designed, fabricated and installed to provide 10 liters of drinking water per day. As the system operates; it can produce around 2.1 liters of drinking water per hour; and consume 1.8 kW of electricity. The system has been designed to be able to use two types of power sources: one from solar energy (main source) and the other from the national grid (auxiliary source).