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In order to address the greenhouse effect and achieve the artificial carbon cycle, the electrocatalytic reduction reactions offer an effective approach for converting carbon dioxide (CO2) into valuable chemicals. In addition to the rational design of catalyst structure to improve the high selective conversion of CO2, exploring the influence of environmental conditions on the reaction path and product types is one of the keys to realizing the high selective conversion of CO2. In this review, we illustrate the important influence of changes in environmental conditions on the effectiveness of electrocatalytic carbon dioxide reduction reaction (CO2RR) technology from the design of the reactor, the selection of the electrolyte, and the setting of the reaction conditions (pressure, temperature, etc.). Through in‐depth understanding and optimization of these factors, the efficiency and selectivity of the CO2RR can be further improved to promote the development of CO2 conversion technology. [ABSTRACT FROM AUTHOR]

• Experimental performance analysis of a CO 2 DX-SAHP. • COP decreases when the water inlet temperature increases. • The augment of solar radiation increases COP. • COP slightly increases due to the humidity increases. In the past decades, combined solar energy with heat pump systems has been one of the very widespread ways to improve the efficiency of conventional heat pumps. In that way, this paper presents an experimental analysis of the influence of environmental conditions in a small size DX-SAHP operating with CO 2 as refrigeration fluid to heat water. The variation of the water inlet temperature, the solar radiation flux and the relative humidity are analyzed and 88 different experimental results are presented. To support the analysis, a thermographic camera was also used. The results show that the gas cooler outlet pressure and temperature are strongly influenced by the water inlet temperature. As the water inlet temperature increases, the gas cooler outlet pressure and temperature increase, and consequently the COP decreases. The COP decreases in 45.8% for the variation of the water inlet temperature to 15–35 oC. The variation of the solar radiation of 876.9–30.17 W.m-2 presents a reduction of performance in about 30%. For the same conditions for the water heat exchange, the pressure ratio of the cycle decreases with an augment on the solar radiation flux. In addition, the COP is higher in 6% for a change in the mean relative humidity of 31.6–55.8 %. [ABSTRACT FROM AUTHOR]

Contaminated gases emissions from livestock industry are becoming one of the most significant contributors to the increasingly serious environmental pollution. To find a way to reduce gases emissions, it is essential to reveal the factors that can affect the gases emissions. In this study, the concentrations of typical gases (including ammonia (NH3), carbon dioxide (CO2), hydrogen sulfide (H2S), and sulfur dioxide (SO2)) generated from naturally-ventilated dairy cow barns were detected through the sample-data method in Tianjin, northern China. Indoor environmental conditions, such as temperature (T) and relative humidity (RH), were measured simultaneously. After applying the carbon dioxide mass balance method, ammonia, hydrogen sulfide and sulfur dioxide emissions were determined. The correlation analysis and regression analysis between the climate condition and gas emissions were conducted to assess the data collected in dairy cow barns during the whole study period. There was a significant relationship between environmental conditions and gas emissions. NH3, H2S and SO2 emissions from the building are in the range of 0.98-2.36 g/LU⋅h, 0-0.034 g/LU⋅h, and 0-0.069 g/LU⋅h, respectively. The numerical analysis shows that the NH3 emission is highly correlated with the temperature and relative humidity. The ventilation rate shows a positive correlation with all the three gases. [ABSTRACT FROM AUTHOR]