排序方式: 共有133条查询结果,搜索用时 234 毫秒
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Akbar Tayebi Mohammad Shahbazi Nia Esmaeil Peyghan 《Linear algebra and its applications》2012,437(2):675-683
In this paper, we characterize locally dually flat generalized m-th root Finsler metrics. Then we find a condition under which a generalized m-th root metric is projectively related to a m-th root metric. Finally, we prove that if a generalized m-th root metric is conformal to a m-th root metric, then both of them reduce to Riemannian metrics. 相似文献
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Energy and environment are key issues for the sustainable development of human beings and are also the current and long‐term focuses of scientific research. New energy and environmental technologies in combination with polymer and textile science work to create many additional functions for conventional polymers and fabrics. Therefore, some novel technical polymers and textiles, such as photovoltaic and photocatalytic polymers and textiles, have begun to emerge. Generally, light‐activated chemicals, materials, or processes that are produced or enabled by light and the agent absorbing light starting a photochemical alteration in the system is nominated as photocatalyst. This review firstly introduces the different photoactive materials, their classifications, and degradation mechanism. Then, inorganic semiconductor nanoparticles were selected as the best candidate for the application in soft materials. Finally, a detailed study was provided on both preparations of photoactive soft materials using metal oxide semiconductors and their advantages and applications. This paper will be more helpful for the scientists working in the field of photoactive soft materials. 相似文献
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Safaei-Ghomi Javad Akbarzadeh Zeinab Teymuri Raheleh 《Research on Chemical Intermediates》2019,45(6):3425-3439
Research on Chemical Intermediates - Zinc oxide nanoparticles immobilized on a graphitic carbon nitride (ZnS NPs/g-C3N4) nanocomposite were applied as an organometallic recyclable catalyst in the... 相似文献
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Borhan Arghavani Nia Masoud Shahrokhi Matin Sedighi 《Chinese Journal of Physics (Taipei)》2018,56(6):2796-2804
In this work by applying first principles calculations structural, electronic and optical properties of Ca3Bi2 compound in hexagonal and cubic phases are studied within the framework of the density functional theory using the full potential linearized augmented plane wave (FP-LAPW) approach. According to our study band gap for Ca3Bi2 in hexagonal phase are 0.47, 0.96 and 1?eV within the PBE-GGA, EV-GGA and mBJ-GGA, respectively. The corresponding values for cubic phase are 1.24, 2.08 and 2.14?eV, respectively. The effects of hydrostatic pressure on the behavior of the electronic properties such as band gap, valence bandwidths and anti-symmetry gap are investigated. It is found that the hydrostatic pressure increases the band widths of all bands below the Fermi energy while it decreases the band gap and the anti-symmetry gap. In our calculations, the dielectric tensor is derived within the random phase approximation (RPA). The first absorption peak in imaginary part of dielectric function for both phases is located in the energy range 2.0–2.5?eV which are beneficial to practical applications in optoelectronic devices in the visible spectral range. For instance, hexagonal phase of Ca3Bi2 with a band gap around 1?eV can be applied for photovoltaic application and cubic phase with a band gap of 2?eV can be used for water splitting application. Moreover, we found the optical spectra of hexagonal phase are anisotropic along E||x and E||z. 相似文献
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Nia Petrova Momchil Paunov Petar Petrov Violeta Velikova Vasilij Goltsev Sashka Krumova 《Molecules (Basel, Switzerland)》2021,26(19)
Single-walled carbon nanotubes (SWCNT) have recently been attracting the attention of plant biologists as a prospective tool for modulation of photosynthesis in higher plants. However, the exact mode of action of SWCNT on the photosynthetic electron transport chain remains unknown. In this work, we examined the effect of foliar application of polymer-grafted SWCNT on the donor side of photosystem II, the intersystem electron transfer chain and the acceptor side of photosystem I. Analysis of the induction curves of chlorophyll fluorescence via JIP test and construction of differential curves revealed that SWCNT concentrations up to 100 mg/L did not affect the photosynthetic electron transport chain. SWCNT concentration of 300 mg/L had no effect on the photosystem II donor side but provoked inactivation of photosystem II reaction centres and slowed down the reduction of the plastoquinone pool and the photosystem I end acceptors. Changes in the modulated reflection at 820 nm, too, indicated slower re-reduction of photosystem I reaction centres in SWCNT-treated leaves. We conclude that SWCNT are likely to be able to divert electrons from the photosynthetic electron transport chain at the level of photosystem I end acceptors and plastoquinone pool in vivo. Further research is needed to unequivocally prove if the observed effects are due to specific interaction between SWCNT and the photosynthetic apparatus. 相似文献
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Raheleh Bakhshi Ebrahim Vasheghani‐Farahani Hamid Mobedi Ahmad Jamshidi Mazyar Khakpour 《先进技术聚合物》2006,17(5):354-359
Biodegradable in situ forming drug delivery systems for naltrexone release are promising for post‐treatment of drug addicts. The effect of two different additives, glycerol and ethyl heptanoate, on the naltrexone hydrochloride release and solvent removal from a poly(DL ‐lactide‐co‐glycolide) (PLGA) injectable implant is presented in this article. The experimental results showed that the in vitro initial release of the drug was decreased in the presence of these additives. Ethyl heptanoate was, however, more effective than glycerol and increasing the amount of additives in PLGA solution up to 5% (w/w) resulted in a decrease of initial naltrexone release rate up to 50%. The morphological evaluation of implants using scanning electron microscopy indicated that the additives generated a less porous structure together with a finger‐like to sponge‐like transition. The solvent removal profiles of injectable implants, which can be well described by thermogravimetric and morphological analysis, were in good agreement with drug release profiles. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献