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The present article introduced a novel idea for information hiding namely steganography. We have used new notions for the construction of the nonlinear component for block cipher based on inverse LA-semigroups. This nonlinear component fundamentally provides confidentiality in the proposed steganographic algorithm. The construction of the algorithm is fundamentally twofold. Firstly, we have constructed a novel scheme to design confusion component namely substitution box (S-box). Secondly, we have utilized the anticipated nonlinear component in digital steganography. The suggested algorithm is tested for different standard digital images. The authentication of the proposed algorithm is confirmed through statistical analysis.

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Electromagnetic wideband absorption is still perceived as a critical and formidable challenge to address with an unambiguous photonic absorber. Subwavelength metamaterial (MM) unit cells with unique and controlled features have recently gained considerable interest. However, meta-atoms, generated using a quantum-inspired pattern distribution, are underwhelming in existing literature to design photonic absorbers and their potential application to manufacture solar sails is still quite uncommon. In this article, to create a flexible, polarization-insensitive, ultrathin, and broadband MM absorber, quantum interference pattern-inspired design is utilized. Herein, a novel approach to fabricating solar sails for the space exploration incorporates the proposed broadband photonic absorber rather than conventional reflectors. The quantum-inspired meta-absorber (QIMA) exhibits an absorption of over 91% for the visible domain, i.e., 380–800 nm under a conventional plane-polarized source. It is shown in the study that broadband absorbers are almost equivalent to excellent reflectors to design the solar sails in terms of the time-averaged force calculated by utilizing the Maxwell stress tensor method. Thus, the QIMA has the potential to be a viable alternative to reflectors in the design of futuristic solar sails for space exploration. The interference theory model is also utilized to assure the dependability of calculated data, and additionally, the standard AM1.5 solar spectrum is utilized to demonstrate the QIMA's solar-harvesting potentiality.  相似文献   
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Calcium carbonate (CaCO3)/alginate inorganic–organic hybrid particles were synthesized and deposited on to the surface of cotton fabrics with a novel one‐step procedure. The effects of the Ca2+/CO32?/alginate molar ratio on the cotton matrix were investigated. The optimization of the process resulted in a regular shaped hybrid microparticles, and scanning electron microscopy revealed that the particles were uniformly distributed on the surface of the fibers. Dynamic light scattering showed that the particles were about 2 μm in diameter. Moreover, transmission electron microscopy images demonstrated that the core–shell structure of the particles existed along with CaCO3 evenly enfolded into the alginate layer. An X‐ray diffraction pattern displayed that the alginate/CaCO3 hybrid microparticles were a mixture of calcite and vaterite crystal. Fourier transform infrared spectroscopy indicated that CaCO3/alginate hybrid particles formed in situ were the only deposited materials. The thermogravimetric analysis curve indicated a certain mass ratio of the alginate and CaCO3 in the hybrid particles. Furthermore, the drug‐loading and drug‐release properties of the hybrid microspheres were studied, and the results show that the water‐soluble diclofenac sodium could be effectively loaded in the hybrid microparticles and the drug release could be effectively sustained. Finally, both of the microparticles and modified fabrics had good cytocompatibility. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42618.  相似文献   
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Iron deficiency is one of the most common nutritional deficiencies worldwide, in both developing and developed regions. Although the aetiology of iron deficiency and resultant anaemia may be multifaceted, inadequate iron intakes, poor iron absorption and disease status may all be underlying causes. Whilst nutrition and supplement interventions may go some way towards improving iron status in ‘at‐risk’ populations, their efficacy can be questioned. New approaches, including food‐based strategies, may be an alternative means of improving the iron status and health of the public sectors. Economically, food‐based approaches may also be more cost‐effective than iron supplements. This paper aims to discuss how the food industry may play an important role in improving the iron status of public sectors, helping to prevent iron deficiency and need for tablet‐based iron supplements.  相似文献   
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The metal‐free reaction of terminal arylacetylenes with α,α‐dichloroaldimines in 1,1,1,3,3,3‐hexafluoro‐2‐propanol as the sole solvent results in the rapid and selective formation of γ,γ‐dichloro‐β‐amino ketones. In this solvent the expected dichlorinated propargylamines and/or allylic amines are not formed. The dichloromethylene moiety of the aldimine acts as an activating group and is essential to accomplish this transformation. Electron‐rich acetylenes lead to the best results and work well with all imines (with or without α′‐H at the nitrogen substituent), while electron‐deficient acetylenes only reacted with Ntert‐butylaldimines (no α′‐H). The mechanistic pathway showed 1,1,1,3,3,3‐hexafluoro‐2‐propanol to protonate the aldimine, which in the rate‐determining step will react with the arylacetylene to form a resonance‐stabilized allene cation, which is trapped by a HFIP molecule giving rise to an enol ether, which promptly hydrolyzes to furnish exclusively the β‐amino ketones. Using DFT techniques we found that the first C C bond forming step is the rate‐determining step and is associated with a barrier of about 21 kcal mol−1.

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Due to unique physiochemical properties, nanoparticles (NPs) have acquired substantial attention in the field of research. However, threats of ecotoxicity and phytotoxicity have limited their biological applications. In this study in vivo experiments were performed to determine the effect of CuO (12.5, 25 and 50 mg/kg) and ZnO (200, 400 and 600 mg/kg) NPs on growth, and antioxidant activities of Brassica nigra. The results showed that CuO NPs did not affect the seed germination while presence of ZnO NPs in the soil generated an inhibitory effect. Both CuO and ZnO NPs positively influenced the growth of stem and other physiological parameters i.e. stem height increased (23%) at 50 mg/kg CuO while root length decreased (up to 44%) with an increase in the concentration of NPs. Phytochemical screening of apical, middle and basal leaves showed elevated phenolic and flavonoid contents in the range of 15.3–59 μg Gallic Acid Equivalent (GAE)/mg Dry Weight (DW) and 10–35 μg Querceitin Equivalent (QE)/mg DW, respectively, in NPs‐treated plants. Antioxidant activity was higher in CuO NPs‐treated plants as compared to ZnO and control plants. Results conclude that CuO and ZnO NPs at low concentrations can be exploited as nanofertilisers in agriculture fields.Inspec keywords: biochemistry, enzymes, renewable materials, crops, nanoparticles, soil, nanofabrication, zinc compounds, organic compounds, agricultural products, toxicology, nanobiotechnologyOther keywords: antioxidative response, ZnO nanoparticles exposure, soil conditions, unique physiochemical properties, germination, antioxidant activities, brassica nigra plant, antioxidant activity, CuO NP‐treated plants, control plants, ZnO NPs effect, mass 15.3 mug to 59.0 mug, mass 10.0 mug to 35.0 mug, CuO, ZnO  相似文献   
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In this paper new algorithms for the rapid, efficient and accurate evaluation of the standard normal integral and its tail are developed. It is shown how the accuracy of the computation can easily be improved so as to achieve machine accuracy for the particular computer being used.  相似文献   
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