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The study is focused on impact of manure application, rice varieties and water management on greenhouse gas (GHG) emissions from paddy rice soil in pot experiment. The objectives of this study were a) to assess the effect of different types of manure amendments and rice varieties on greenhouse gas emissions and b) to determine the optimum manure application rate to increase rice yield while mitigating GHG emissions under alternate wetting and drying irrigation in paddy rice production. The first pot experiment was conducted at the Department of Agronomy, Yezin Agricultural University, Myanmar, in the wet season from June to October 2016. Two different organic manures (compost and cow dung) and control (no manure), and two rice varieties; Manawthukha (135 days) and IR-50 (115 days), were tested. The results showed that cumulative CH4 emission from Manawthukha (1.084 g CH4 kg-1 soil) was significantly higher than that from IR-50 (0.683 g CH4 kg-1 soil) (P2O kg-1 soil) than for Manawthukha (2.585 mg N2O kg-1 soil). However, IR-50 showed less global warming potential (GWP) than Manawthukha (P4 and N2O emissions were observed in the cow dung manure treatment (0.808 g CH4 kg-1 soil, 2.135 mg N2O kg-1 soil) compared to those of the control and compost. To determine the effect of water management and organic manures on greenhouse gas emissions, second pot experiments were conducted in Madaya township during the dry and wet seasons from February to October 2017. Two water management practices {continuous flooding (CF) and alternate wetting and drying (AWD)} and four cow dung manure rates {(1) 0 (2) 2.5 t ha-1 (3) 5 t ha-1 (4) 7.5 t ha-1} were tested. The different cow dung manure rates did not significantly affect grain yield or greenhouse gas emissions in this experiment. Across the manure treatments, AWD irrigation significantly reduced CH4 emissions by 70% during the dry season and 66% during the wet season. Although a relative increase in N2O emissions under AWD was observed in both rice seasons, the global warming potential was significantly reduced in AWD compared to CF in both seasons (P4. Therefore, AWD is the effective mitigation practice for reducing GWP without compromising rice yield while manure amendment had no significant effect on GHG emission from paddy rice field. Besides, AWD saved water about 10% in dry season and 19% in wet season.

The development of high-performance electrochemical energy storage device is important for addressing energy shortage issues. As one of the next-generation energy storage devices, supercapacitor (SCs) material and their composite designs have gained increased attention in recent years. Herein, the CNT@MoS2/PDDA/PMo12 nanocomposite, was assembled via PDDA-assisted (PDDA is poly(dimethyldiallylammonium chloride)) synthesis strategy. The positively charged polyelectrolyte can interact with two negatively charged components, phosphomolybdic acid (PMo12) and CNT@MoS2 (CNT referred to multi-walled carbon nanotubes, and MoS2 referred to molybdenum disulfide) through electrostatic interaction. PMo12 has uniformly attracted on the surface of the ultrathin MoS2 nanosheets-modified CNT, which endowed the nanocomposite with a fast electron transport efficiency, enrich charge storage and multi-electron transfer capabilities. As a symmetric supercapacitor system, this composite exhibited a high rate specific capacitance of 110 F g−1 at 0.5 A g−1 and an energy density of 15.27 W h kg−1 at a power density of 152 W kg−1. Moreover, an excellent cycle performance with 89% specific capacitance after 10000 charge-discharge cycles was obtained.