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671.
Numerous studies were performed to evaluate the performance of photovoltaic power systems (PV systems), including maximum power control of the solar cell, effects of the PV systems on distribution feeders, long-term performance of the PV systems, etc. To estimate the performance of PV systems, the output characteristics of the solar cell should be taken into consideration. This paper proposes a new method of the simulated power source (SPS) to analyze the PV system. The SPS is under the control of the 10 cm2 reference solar cell, hence, the output characteristics of the SPS are in proportion not only to the static output characteristics of the reference solar cell, but also the dynamic ones. 相似文献
672.
Vinyl-type monomers containing bromine and/or phosphorus were synthesized and used as flame retardants for ethylene–propylene–diene terpolymer. The monomers were mixed with the base polymer, Sb2O3 as a synergist, radical initiator, and other additives, and polymerized in the matrix of the base polymer. The monomers act as an effective flame retardants when they form thermally stable polymers comparable to the base polymer. The efficiency was dependent on the amount of flame-retardant polymer formed in the finished compound. 相似文献
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A multireflection multi/demultiplexer using interference filters is proposed. Light waves of different wavelengths are combined or separated while they propagate between two filter arrays. The insertion loss of the 6-channel demultiplexer was around 1dB. 相似文献
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The temperature dependence of the 1H-NMR absorption in coals and pitches have been obtained using a pulsed Fourier transform NMR spectrometer with a high temperature probe. The samples as received were heated in the high temperature probe and NMR spectra were obtained simultaneously. With increasing temperature, the value of the line width at half-height (ΔH1/2) of a brown coal decreases and then increases rapidly. On the other hand, tar pitch and the γ component of a coal indicate that the values of ΔH1/2 remain small over a wide temperature range. It is found that there is an excellent relation between the temperature dependence of ΔH1/2 and the optical texture of the mesophase. 相似文献
680.
Curing reaction of elastomers with triazine thiols and sulfen amides in the presence of ZnO and stearic acid was investigated for curing parameters and curing mechanism. The curing parameters such as curing rate, induction period, and curing efficiency were influenced by the pKa of thiol groups in triazine thiols and amines corresponding in sulfen amides, by the steric hinderance of 6-substituted groups in triazine thiols and on amino groups in sulfen amides, by the molar ratio of sulfen amides to triazine thiols, and by the reacting positions and the properties of elastomers. Triazine thiols acted as curing agents. Sulfen amides played two important roles in curing elastomers with triazine thiols. They gave poly(triazinyl disulfide) which is a curing precursor. Curing activators are formed in the reaction of the precursors, sulfen amides, and ZnO. The activators react with elastomers to give crosslinks, pendants and triazine dithiols or triazinyl disulfide oligomers. The pendants react with sulfen amides to give the crosslinks. The triazine thiols or triazinyl disulfide oligomers react with sulfen amides to reproduce the curing precursors. The structure of crosslinks is estimated to be 相似文献