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91.
Yuhei Horio Md. Mijanur Rahman Yurei Imai Yoshihiro Hishikawa Takashi Minemoto 《Current Applied Physics》2017,17(10):1341-1346
The output energy of photovoltaic (PV) modules is influenced by the spectral irradiance distribution of the solar spectrum under outdoor conditions. To rate the precise output energy of PV modules, the correction of short circuit current (ISC) based on actual environmental conditions is needed, because ISC significantly depends on the shape of the spectral irradiance distribution. The average photon energy (APE) is a zero-dimensional index for spectral irradiance distribution, and APE value uniquely describes the shape of a solar spectrum. Thus, APE has an impact on ISC of PV modules. In this contribution, the relationship between APE coefficient and ISC of the multi-crystalline silicon, single-crystalline silicon, heterojunction intrinsic thin-layer, back contact, copper indium selenide and cadmium telluride PV modules has explored. It is revealed that APE value changes the ISC of PV modules which appeared to have immense possibilities of ISC correction using APE coefficient. This new approach can be very effective for precise rating the output energy of PV modules under actual outdoor conditions. 相似文献
92.
Mazloum-Ardakani Mohammad Sabaghian Fariba Khoshroo Alireza Abolhasani Mahboobe Naeimi Hossein 《Ionics》2015,21(1):239-250
Ionics - A novel carbon paste electrode (CPE) modified with 2,2′-[1,7–heptanediylbis(nitrilomethylidene)]-bis(4-hydroxyphenol) (DHB) and carbon nanotubes (CNTs) was prepared. At first,... 相似文献
93.
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95.
Mohammad R. Ahmady Dongsheng Liu Amir H. Fariborz 《The European Physical Journal C - Particles and Fields》2011,71(1):301-305
Short and long distance contributions to the exclusive B-decays into various K-resonances and dileptons, i.e. $B \to K^i \ell \bar \ell (\ell = e,\mu ,\nu )$ , are examined. The heavy quark effective theory has been used to calculate the hadronic matrix elements. Substantial branching fractions are obtained for the dileptonic B-decays into some higher excited states of K-mesons. The long distance (resonance) contributions to these exclusive rare B-decay modes dominate the short distance contributions mostly by two orders of magnitude. It is pointed out that, excluding the resonance contributions, the P-wave channels are dominant, accounting for about 50% of the inclusiveB??X s ? + ? ? branching fraction. 相似文献
96.
We report on the fabrication and characterization of nanoscale solid immersion lenses (nano-SILs) with sizes down to a subwavelength range. Submicrometer-scale cylinders fabricated by electron-beam lithography are thermally reflowed to form a spherical shape. Subsequent soft lithography leads to nano-SILs on transparent substrates for optical characterization. The optical characterization is performed using a high-resolution interference microscope with illumination at 642 nm wavelength. The focal spots produced by the nano-SILs show both spot-size reduction and enhanced optical intensity, which are consistent with the immersion effect. 相似文献
97.
We consider the tachyon-brane inflationary universe model in the context of a polytropic gas equation of state. In slow-roll approximation, we discuss general conditions of this model. For exponential potential, in high-energy limit the characteristics of the model are presented. By using the seven-year Wilkinson Microwave Anisotropy Probe (WMAP7) observational data, we constrain the cosmological parameters of the model. 相似文献
98.
Davood Momeni Muhammad Raza Mohammad Reza Setare Ratbay Myrzakulov 《International Journal of Theoretical Physics》2013,52(8):2773-2783
The holographic model for a two-dimensional superconductor has been investigated by considering the three-dimensional gravity in the bulk. To find the critical temperature, we used the Sturm–Liouville variational method. Where as the same method is applied for calculating the condensation of the dual operators on the boundary. We included the back reactions on the metric by a combination of the perturbation method of the fields with respect to the small parameter and then applying the variational integrals on the resulting equations of the motion. The critical temperature has been successfully obtained on the backreaction effects, and we showed that it dropped with a rise in the backreaction of the fields, and it makes the condensation harder. We can use our analytical results to support the numerical data which was reported previously. 相似文献
99.
Spin-flip (paramagnetic) scattering and neutron depolarization studies were performed on Ce2Fe17 in its paramagnetic phase on the Dhruva neutron polarization analysis spectrometer. The absence of normalQ dependence of the scattered spin flip intensity shows that Ce2Fe17 is not a normal paramagnetic and there exist superparamagnetic clusters of sufficiently large dimensions (~100Å). The observed neutron depolarization gives an indication of the dynamics of these Ce2Fe17 superparamagnetic clusters. 相似文献
100.
Tsutomu Asano Takuro Furusho Mohammad Mahay Alam Yukihiro Tamba Chie Sawatari Md. Forhad Mina 《Journal of Macromolecular Science: Physics》2013,52(4):774-788
Isotactic polypropylene (iPP) film was melt-crystallized in a temperature gradient. The iPP film showed well oriented α- and β-crystalline textures along the gradient. The crystalline structure, phase transition boundary and lamellar twisting were examined by X-ray diffraction and laser light diffraction (LLD). On the α-β boundary, LLD shows a sharp streak perpendicular to the boundary, where the a-axis of the β-crystal is oriented perpendicular to the temperature gradient. Apart from the boundary, the a-axis of the β-crystal becomes parallel to the gradient. The β-crystal shows lamellar twisting with a pitch of 200 μm at room temperature. When heated the β-crystal, the lamellar distance of 295Å at room temperature decreases to 285Å at 80–100°C and then increases to more than 300Å above 120°C. During the heating, the value of the twist period increases from 200 to 210 μm at 90–100°C, and then to above 224 μm at 140°C. The increase of the twist period is related to the increasing crystalline thickness of the β-lamellae. 相似文献