Advanced Materials Research Vols. 347-353

Abstract: The rising international oil prices will cause the loss of national GDP and the establishment of strategic petroleum reserves (SPR) could avoid this loss as much as possible. The oil price-GDP elasticity coefficient is an important parameter in calculating strategic petroleum reserve, but since it is difficult to obtain, it is also hard to calculate. This paper provides the fitting formula of oil price-GDP elasticity coefficient based on the regression analyzing of literature data. China’s oil price-GDP elasticity coefficient in recent years has been analyzed and predictions for future trends in different situations have been made. Finally, the predicted oil price-GDP elasticity coefficient is used to calculate the size of China's strategic petroleum reserve and its earnings.

Abstract: With the development of urban central heating, remote monitoring technology plays an important role in the heating network monitoring, control and management. The system, which uses the remote transmission manner of data radio, collects steam parameters from every steam-using corporation and sends them to the monitoring center of thermoelectricity plant, then analyses and disposes the data through the monitoring software of LabVIEW, brings forward a heating network load forecasting method based on wavelet and Neural network, decomposes load sequence to use wavelet packet, processes Elman network model training for subsequence, and recomposes the load forecasting results.

Abstract: Coarse woody debris (CWD) is composed of dry wood, fallen wood and large branches, and it is an important element for structure and function in forest ecosystems. In this paper, we studied the characteristics of coarse woody debris (CWD) of natural Larix gmelinii forests with different ages in Daxing’anling Mountains. The results show that (1) the CWD volumes in near-mature, middle-age and young forests are 88.55 m3•hm-2, 52.07 m3•hm-2 and 3.96 m3•hm-2, respectively; and their biomasses are 52.96 t•hm-2, 36.22 t•hm-2 and 2.35t•hm-2, respectively. Which indicate that the CWD volumes and biomasses increase with forest ages addition; (2) The CWD volume and biomass follow normal distribution in middle and near-mature forest; (3) the CWD volume and biomass decrease with forest age increasing within decay classes I and II, whereas increase in decay classes III, IVand V; (4) the volume of middle-age and young forests present a near normal distribution with decay class increasing.

Abstract: The characteristic of solar chimney power plant system is analyzed. For the key issue of low efficiency in solar chimney power plant system, a solar thermal power system with gas-liquid injector and hydroturbine is presented. This new system obtain the energy transferred process by gas-liquid injector. It is solar energy transformed into thermodynamic energy into potential energy and then into electricity. The density difference of work fluid is increased by gas-liquid phase transition in running process.The efficiency of solar thermal power generation is increased. In the case of the same cost, the theory power efficiency of new system increases one order of magnitude compared with the solar chimney power plant system. It proposes a new solution for large-scale application of solar thermal power technology.

Abstract: _{Subscript text}CO₂ emission control is an important issue, in which chemical absorption process has reached the widest application. Ionic liquid is a kind of green solvent and expected to take the place of traditional amine absorbents as for its better characteristics. In this paper, two iminazole base ionic liquids were synthesized, including of bromide 1-butyl-3-methylimidazo ([bmim]Br) and 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF₆). The performance of CO₂ absorption by [bmim]PF₆ and [bmim]Br were compared under the same other conditions. _{Subscript text}It indicates that [bmim]PF₆ has more absorption capacity and less saturated absorption time under low temperature, which provides reference for CO₂ control by ionic liquid.

Abstract: In this paper, a new type fault current limiter (FCL) topology is put forward for Micro-Grid (MG) system fault, which mainly consists of limiting inductance, bypass inductance and series compensation capacitors. The switching circuit is used to change circuit structure through the power diode bridge and FGCT, in the event of a fault the current limiting inductance is switched to limit short-circuit current. The topology has the advantages of switch quickly, simple control, and series compensation effect. Establishes a equivalent model of MG system with FCL, discusses the impact of FCL installation location to system short-circuit protection, and proposes the installation location program. Matlab is used for system modeling and simulation results show that the effect of the current limiter, which is installed on the outlet of the MG system power for three-phase short-circuit protection, is obvious, and has the function of inhibiting voltage sag.

Abstract: A series of copolymers P(MMA-NVP) composed of methyl methacrylate (MMA) and N-vinyl pyrrolidone (NVP) were prepared by a solution copolymerization technique. The copolymer could absorb and capture amount of liquid electrolyte within its chain networks structure to form quasi-solid-state electrolyte. The influences of synthesis conditions for copolymers, such as the content of NVP, the amount of initiator 2,2’-azobisisobutyronitrile(AIBN), and the amount of crosslinking agent triethylene glycol dimethacrylate(TEGDMA) on the ionic conductivity of quasi-solid electrolyte were investigated. The highest conductivity of the copolymer gel was 2.17mS/cm at 25°C. Based on the copolymer gel electrolyte, a dye-sensitized solar cell was fabricated with short-circuit current of 12.16mA/ cm², open circuit voltage of 619mV, fill factor of 0.4633 and an overall conversion efficiency of 3.05 % under 100 mW/cm2 irradiation (AM1.5).

Abstract: The hydraulic impactor is the key component that affects the hydraulic impact mechanical properties. Impact energy or impact power parameter is the important indication of impact system performance. The conditional parameters affecting the basic function were analyzed in this paper. The pressure change and flow of different working cavity in the working process were experimental studied on the experimental device. The relationships between the rate of flow and pressure in the impactor were also discussed.

Abstract: Power unit coordinate control problem is a typical non-linear, constrained optimization problem with high computational complexity, in which the optimal solution is balanced between unit load demand and pressure set point. This problem is traditionally solved by fixed nonlinear mapping method, while more and more attention is payed on solving this issue with modern heuristic algorithms, like GA, PSO, etc. This paper presents a comparison study between two typical modern heuristic algorithms with their applications to a 3-objective power unit coordinate control problem. The merits and drawbacks of each algorithm is analyzed via simulation experiments.

Abstract: The use of colloidal solution deposition method on the preparation of the nanostructured TiO2 thin film for dye-sensitized solar cells in basic laboratory conditions was introduced. The effects of reaction temperature, time, and solvents on the film properties have been investigated. The experiments show that the use of dilute acetic acid could get a stable sol; 450°C 30 minutes in oven without preheat could have ideal TiO2 thin film.