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601.
We report enhanced anomalous photovoltaic effects and switchable photovoltage generation in pure and Pr–Cr co‐doped BiFeO3 (BFO) nanotubes (NTs). Influence of metal doping on short circuit current, open circuit voltage, power conversion efficiency and fill factor are investigated. The power conversion efficiency of pure BFO NTs (~0.207%) is found to be enhanced by several orders of magnitude in comparison with the reported bulk effect. Pr‐doped NTs provide highest values of power conversion efficiency (~0.5%).

  相似文献   

602.
LCZ696 displays several surprising features, such as an intrinsic stabilization of the supramolecular complex by monovalent multi-coordinated sodium cations and water molecules. In addition, to the best of our knowledge, the compound is the first example of a dual-acting pharmaceutical built as a supramolecular complex delivering two pharmacologic effects—angiotensin receptor 1 (AT1) blockage and neprilysin (NEP) inhibition.  相似文献   
603.
604.
A new bimetallic complex of nickel(II) coordinated to a molybdenum-containing metalloligand has been synthesized that forms a helical chain through hydrogen bonding and shows spontaneous resolution upon crystallization.  相似文献   
605.
In this study, alkaliphilic family G/11 xylanase from alkali-tolerant filamentous fungi Penicillium citrinum MTCC 6489 was used as a model system to gain insight into the molecular aspects of unfolding/refolding of alkaliphilic glycosyl hydrolase protein family. The intrinsic protein fluorescence suggested a putative intermediate state of protein in presence of 2 M guanidium hydrochloride (GdmCl) with an emission maximum of 353 nm. Here we studied the refolding of GdmCl-denatured alkaline xylanase in the presence and the absence of a multimeric chaperone protein α-crystallin to elucidate the molecular mechanism of intramolecular interactions of the alkaliphilic xylanase protein that dictates its extremophilic character. Our results, based on intrinsic tryptophan fluorescence and hydrophobic fluorophore 8-anilino-1- naphthalene sulfonate-binding studies, suggest that α-crystallin formed a complex with a putative molten globule-like intermediate in the refolding pathway of xylanase in an ATP-independent manner. A 2 M GdmCl is sufficient to denature alkaline xylanase completely. The hydrodynamic radius (RH) of a native alkaline xylanase is 4.0, which becomes 5.0 in the presence of 2 M GdmCl whereas in presence of the higher concentration of GdmCl RH value was shifted to 100, indicating the aggregation of denatured xylanase. The α-crystallin·xylanase complex exhibited the recovery of functional activity with the extent of ~43%. Addition of ATP to the complex did not show any significant effect on activity recovery of the denatured protein.  相似文献   
606.
An extension GH of lattice-ordered groups is said to be a rigid extension if for each ${h \in H}An extension GH of lattice-ordered groups is said to be a rigid extension if for each h ? H{h \in H} there exists a g ? G{g \in G} such that h ⊥⊥ = g ⊥⊥. In this paper, we will define rigid extensions and some other generalizations in the context of algebraic frames satisfying the FIP. One of the main results is a characterization of rigid extensions using d-elements of the frame. We also show that a rigid extension between two algebraic frames satisfying the FIP will induce a homeomorphism between their corresponding minimal prime spaces with respect to both the hull-kernel topology and the inverse topology. Moreover, basic open sets map to basic open sets.  相似文献   
607.
608.
We show that a recently proposed [J. Fleischer, P.H. Diamond, Phys. Rev. E 58, R2709 (1998)] one-dimensional Burgers-like model for magnetohydrodynamics (MHD) is in effect identical to existing models for drifting lines and sedimenting lattices. We use the model to demonstrate, contrary to claims in the literature, that the energy spectrum of MHD turbulence should be independent of mean magnetic field and that cross-correlations between the noise sources for the velocity and magnetic fields cannot change the structure of the equations under renormalisation. We comment on the scaling and the multiscaling properties of the stochastically forced version of the model. Received 29 October 1998 and Received in final form 8 December 1998  相似文献   
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610.
Aldehydes serve as the key functional group in organic synthesis and are valuable intermediates. The various advanced methods of direct formylation reactions have been reviewed in this article. Overcoming the drawbacks of the traditional methods of formylation, newer methods involving homo and heterogenous catalysts, one pot reactions, solvent free techniques are elaborated, which can be performed under mild conditions and using inexpensive resources.  相似文献   
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