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YO:Eu and YO:Eu/Bi particles with spherical morphology are synthesized by microwave-assistant hydrothermal process. The results show that cubic phase YO:Eu and YO:Eu/Bi particles with uniform size and spherical shape are obtained. The doping Eu and Bi ion have no influence on the phase and morphology of samples. In the hydrothermal process, the fast and homogeneous microwave heating benefits the formation of samples with uniform size and spherical shape. Both YO:Eu and YO:Eu/Bi show dominant red emission originating from the D → F transition of Eu. The codoping Bi can enhance the intensity of Eu emission. [ABSTRACT FROM AUTHOR]

A lanthanide metal coordination polymer [Eu2(BDC)3(DMSO)(H2O)] was synthesized by the reaction of europium oxide with benzene-1,3-dicarboxylic acid (H2BDC) in a mixed solution of dimethyl sulfoxide (DMSO) and water under hydrothermal conditions. The crystal structure of Eu2(BDC)3(DMSO)(H2O) was characterized by X-ray diffraction (XRD). Thermo-gravimetric analysis of Eu2(BDC)3(DMSO)(H2O) indicated that coordinated DMSO and H2O molecules could be removed to create Eu2(BDC)3 (DMSO)(H2O)-py with permanent microporosity, which was also verified by powder XRD (PXRD) and elemental analysis. Both Eu2(BDC)3(DMSO)(H2O) and Eu2(BDC)3(DMSO)(H2O)-py showed mainly Eu-based luminescence and had characteristic emissions in the range 550-700 nm. [ABSTRACT FROM AUTHOR]

Measurements of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, conventional measurement requires expensive detection devices and undergoes a series of complicated procedures. To simplify the measurement and reduce the cost, software based on artificial neural networks for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters was developed. Using multilayer feed-forward neural networks with back-propagation algorithm, we developed and tested our program on the basis of 915measuredsamples of water-in-glass evacuated tube solar water heaters. This artificial neural networks-based software program automatically obtained accurate heat collection rateand heat loss coefficient using simply "portable test instruments" acquired parameters, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, angle between tubes and ground and final temperature. Our results show that this software (on both personal computer and Android platforms) is efficient and convenient to predict the heat collection rate and heat loss coefficient due to it slow root mean square errors in prediction. The software now can be downloaded from . [ABSTRACT FROM AUTHOR]

• HCHO oxidation by oxygen on FeN 3 -graphene surface was investigated using DFT method. • L-H mechanism plays a leading role in the oxidation of HCHO. • The HCHO oxidation reaction can be carried out spontaneously and irreversibly. • The desorption energy of the product was only 0.89 eV. • FeN 3 -graphene can be a potential and efficient catalyst for the oxidation of HCHO. Developing high activity and low cost catalyst for oxidative degradation of HCHO is critical for reduction HCHO pollution in indoor air. Herein, we proposed FeN 3 -graphene as a novel catalyst to oxidatively degrade HCHO into non-toxic H 2 O and CO 2. The DFT calculations were used to systematically study the reaction mechanism of HCHO oxidation by oxygen on the surface of FeN 3 -graphene. The L-H and E-R reaction mechanisms were adopted to guide the exploration of possible catalytic reaction pathways, and the change rules in equilibrium and rate of reaction at different reaction temperatures were obtained by thermodynamic and kinetic analysis. Five HCHO oxidative degradation paths were obtained, and the formaldehyde oxidation reaction can be carried out spontaneously and irreversibly within the temperature range of 300–800 K. At the same time, temperature showed a promoting effect on the reaction rate. The minimum activation energy is 0.95 eV, and the product needs only 0.89 eV to desorb from the catalyst surface, indicating that the catalyst has potential for practical application. Our theoretical prediction work can provide a new direction for the research and development of formaldehyde removal catalyst, and provide theoretical guidance for experimental research. [ABSTRACT FROM AUTHOR]

To promote the application of renewable energy in low-energy buildings in Alpine regions, a solar-air source heat pump (SASHP) system was investigated based on a low-energy residential building in Xining City. First, a solar fresh air (SFA) heating system simulation model was established in TRNSYS software, and the reliability of the model was verified with measured values. In addition, based on the SFA heating system model, a SASHP system model was further realized. The operating characteristics of the SASHP system were explored in depth and compared with those of the single-ASHP system in the heating season. The results show that the SFA heating system model is reliable, with relative errors that can be controlled within 15%. The indoor average temperature (T ave) can be maintained from 16.13 to 19.61 °C. The SASHP system can leads to T ave fluctuations within the range of 21.4–22.9 °C, and the solar fraction can reach 55% in the heating season. Furthermore, the SASHP system can reduce energy consumption by 55.38% compared to the ASHP system; additionally, the COP of the SASHP system is 109.43% higher than that of the ASHP system, and the annual cost is 9.7% lower. Moreover, the SASHP system produces 55.48% less carbon emissions than the ASHP system. These results provide guidance for the application of SASHP systems in Alpine regions. [ABSTRACT FROM AUTHOR]

A lanthanide metal coordination polymer [Eu2(BDC)3(DMSO)(H2O)] was synthesized by the reaction of europium oxide with benzene-1,3-dicarboxylic acid (H2BDC) in a mixed solution of dimethyl sulfoxide (DMSO) and water under hydrothermal conditions. The crystal structure of Eu2(BDC)3(DMSO)(H2O) was characterized by X-ray diffraction (XRD). Thermo-gravimetric analysis of Eu2(BDC)3(DMSO)(H2O) indicated that coordinated DMSO and H2O molecules could be removed to create Eu2(BDC)3(DMSO)(H2O)-py with permanent microporosity, which was also verified by powder XRD (PXRD) and elemental analysis. Both Eu2(BDC)3(DMSO)(H2O) and Eu2(BDC)3(DMSO)(H2O)-py showed mainly Eu-based luminescence and had characteristic emissions in the range 550-700 nm., (Copyright © 2015 John Wiley & Sons, Ltd.)