A new indicator with temperature dependence of the NO3 loss frequency, was developed to study the contribution of NO3 to the oxidation of monoterpenes and NOx removal in the atmosphere. The new indicator arises from t...A new indicator with temperature dependence of the NO3 loss frequency, was developed to study the contribution of NO3 to the oxidation of monoterpenes and NOx removal in the atmosphere. The new indicator arises from the temperature dependence of kinetic constant. The new indicator was applied to data of observation based on differential optical absorption spectroscopy system on the outskirts of Hefei, China. According to the findings, the contribution of monoterpenes to the loss of NO3 was 70%-80%.展开更多
We present the electronic structure and electron energy loss spectroscopy (EELS) for uranium, niobium and U3Nb in which uranium is substituted by niobium. Comparing the electronic structures and optical properties for...We present the electronic structure and electron energy loss spectroscopy (EELS) for uranium, niobium and U3Nb in which uranium is substituted by niobium. Comparing the electronic structures and optical properties for uranium, niobium and U3Nb, we found that when niobium atom replaces uranium atom in the center lattice, density of state (DOS) of U3Nb shifts downward to low energy. Niobium affects DOS for f and d electrons more than that for p and s electrons. U3Nb is similar to uranium for the electronic energy loss spectra.展开更多
Common solar-driven photoelectrochemical(PEC) cells for water splitting were designed by using semiconducting photoactive materials as working photoelectrodes to capture sunlight. Due to the thermodynamic requirement ...Common solar-driven photoelectrochemical(PEC) cells for water splitting were designed by using semiconducting photoactive materials as working photoelectrodes to capture sunlight. Due to the thermodynamic requirement of 1.23 eV and kinetic energy loss of about 0.6 eV, a photo-voltage of 1.8 V produced by PEC cells is generally required for spontaneous water splitting. Therefore, the minimum bandgap of1.8 eV is demanded for photoactive materials in single-photoelectrode PEC cells, and the bandgap of about 1 eV for back photoactive materials is appropriate in tandem PEC cells. All these PEC cells cannot effectively utilize the infrared light from 1250 to 2500 nm. In order to realize the full spectrum utilization of solar light, here, we develop a solar-driven PEC water splitting system integrated with a thermoelectric device. The key feature of this system is that the thermoelectric device produces a voltage as an additional bias for the PEC system by using the temperature difference between the incident infrared-light heated aqueous electrolyte in the PEC cell as the hot source and unirradiated external water as the cold source. Compared to a reference PEC system without the thermoelectric device, this system has a significantly improved overall water splitting activity of 1.6 times and may provide a strategy for accelerating the application of full spectrum solar light-driven PEC cells for hydrogen production.展开更多
基金ACKNOWLEDGMENTS We acknowledged to DOAS groups. This work was supported by the Key Project of Chinese Ministry of Education （No.209057）, the Anhui Provincial Natural Science Foundation （No.090412028）, and the Natural Science Foundation of Anhui Province Colleges and University （No.KJ2008A114）.
文摘A new indicator with temperature dependence of the NO3 loss frequency, was developed to study the contribution of NO3 to the oxidation of monoterpenes and NOx removal in the atmosphere. The new indicator arises from the temperature dependence of kinetic constant. The new indicator was applied to data of observation based on differential optical absorption spectroscopy system on the outskirts of Hefei, China. According to the findings, the contribution of monoterpenes to the loss of NO3 was 70%-80%.
基金Supported by the National Key Laboratory Foundation of China (9140C6601010804)Sichuan Provincial Key Laboratory for Applied Nuclear Technology in Geology Foundation (27-7).
文摘We present the electronic structure and electron energy loss spectroscopy (EELS) for uranium, niobium and U3Nb in which uranium is substituted by niobium. Comparing the electronic structures and optical properties for uranium, niobium and U3Nb, we found that when niobium atom replaces uranium atom in the center lattice, density of state (DOS) of U3Nb shifts downward to low energy. Niobium affects DOS for f and d electrons more than that for p and s electrons. U3Nb is similar to uranium for the electronic energy loss spectra.
基金This work was supported by the National Natural Science Foundation of China(51825204 and 51629201)the Key Research Program of Frontier Sciences CAS(QYZDB-SSW-JSC039).
文摘Common solar-driven photoelectrochemical(PEC) cells for water splitting were designed by using semiconducting photoactive materials as working photoelectrodes to capture sunlight. Due to the thermodynamic requirement of 1.23 eV and kinetic energy loss of about 0.6 eV, a photo-voltage of 1.8 V produced by PEC cells is generally required for spontaneous water splitting. Therefore, the minimum bandgap of1.8 eV is demanded for photoactive materials in single-photoelectrode PEC cells, and the bandgap of about 1 eV for back photoactive materials is appropriate in tandem PEC cells. All these PEC cells cannot effectively utilize the infrared light from 1250 to 2500 nm. In order to realize the full spectrum utilization of solar light, here, we develop a solar-driven PEC water splitting system integrated with a thermoelectric device. The key feature of this system is that the thermoelectric device produces a voltage as an additional bias for the PEC system by using the temperature difference between the incident infrared-light heated aqueous electrolyte in the PEC cell as the hot source and unirradiated external water as the cold source. Compared to a reference PEC system without the thermoelectric device, this system has a significantly improved overall water splitting activity of 1.6 times and may provide a strategy for accelerating the application of full spectrum solar light-driven PEC cells for hydrogen production.
