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1.
Engineering with Computers - A novel hybrid many-objective evolutionary algorithm called Reference Vector Guided Evolutionary Algorithm based on hypervolume indicator (H-RVEA) is proposed in this...  相似文献   
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Recently, magnetic bio-composites as adsorbent are widely being explored in waste water treatment because of their exceptional properties like high adsorption capacity, selectivity and cost-effective nature. In the present study, a novel recyclable magnetic composite containing magnetic zinc ferrite and alginate in alginic form (ZnFN–Alg) was developed. Various techniques like Fourier Transform-Infra Red, X-ray diffraction, transmission electron microscope with energy dispersive spectra, Brunauer–Emmett–Teller, thermo gravimetric-differential thermal analysis and Point Zero Charge (pHzpc) were used to characterize the surface morphology of magnetic composite. The magnetic composite was used as adsorbent to remove congo red, crystal violet and brilliant green dyes in single and ternary systems. The kinetic studies data was best fitted to Lagergren pseudo second order whereas mechanism of adsorption was described by intra particle diffusion model in single as well as ternary systems. The adsorption equilibrium data was best fitted to Langmuir isotherm among various adsorption isotherm models. Thermodynamic studies confirmed that the adsorption process was spontaneous in nature. The regeneration ability of ZnFN–Alg composite was studied individually in single and ternary dye systems for seven cycles and showed significant results. It was concluded that magnetic ZnFN–Alg can serve as suitable alternative for the removal of dyes in single and ternary systems.  相似文献   
3.
Neural Computing and Applications - The identification of water stress is a major challenge for timely and effective irrigation to ensure global food security and sustainable agriculture. Several...  相似文献   
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Calcium phosphate cements (CPCs) are ideally suited for the local delivery of antibiotics in infected bone defects as they have multiple binding sites for loading various drugs. CPCs can also be substituted with ions such as Ag+, Zn2+, Mg2+, Sr2+, etc., to exhibit extended broad-spectrum antimicrobial activity. Strontium (Sr) in particular is known to enhance the new bone formation and decrease bone resorption. The current work aims to develop a dual action tetracalcium phosphate (TTCP) based cement which releases both the Sr2+ ion and ornidazole antibiotic drug for the treatment of bone infections. The TTCP with Sr2+ ion substitution was prepared by the solid state reaction method and it was used to form ornidazole loaded CPC. The ornidazole loaded cement prepared using 8?at% Sr substituted TTCP (8SCPC-O) showed complete hydroxyapatite (HA) formation in phosphate buffered solution at the end of 1 week. Fine needle-shaped HA crystals were observed in 8SCPC-O cement. In vitro drug release studies showed an accelerated ornidazole release from the 8SCPC-O sample when compared to samples without Sr substitution. Ornidazole releasing cements were found to be biocompatible with skeletal myoblast (L6) cells. Antibacterial activity of ornidazole releasing cement was evident from day 1 onwards against E. coli. The above results suggest 8SCPC-O as a good candidate for treating local bone infections.  相似文献   
6.
ABSTRACT

In recent years, information security over the internet has gained enormous immersion due to a technological escalation in communication via digital media. Nowadays, videos are the most common form of media over the internet, and they have gained the attention of video steganography research community for the security of the communication. This paper implemented video steganography using a widely-known transform technique, discrete wavelet transform (DWT) which consists of different orthogonal and biorthogonal filters used for the decomposition of a frame/image. The aim of this paper is to provide a comparative evaluation for orthogonal and biorthogonal DWT filters with different matrices such as MSE, PSNR. The performance of the different filters has been evaluated both quantitatively and qualitatively to investigate the best among them. Also, the best of orthogonal and biorthogonal filters have been further evaluated with other metrics such as SSIM, BER and histogram analysis. Further, the embedding algorithm has been compared with the existing video steganography techniques. The experimental results illustrate that bior 6.8 (biorthogonal filter) outperforms the other orthogonal and biorthogonal filters in terms of visual distortion.  相似文献   
7.
Ninety nine mine water discharge samples were collected and analyzed for pH, electrical conductivity (EC), major cations, anions, and trace metals in the Pootkee-Balihari coal mining area of the Jharia coalfield. The mines of the area annually discharge 34.80 × 106 m3 of mine water and 39,099 t of solute loads. The pH of the analyzed mine waters ranged from 6.97 to 8.62. EC values ranged from 711 μS cm−1 to 1862 μS cm−1, and reflect variations in lithology, geochemical processes, and hydrological regimes in the mines. The cation and anion chemistry indicate the general ionic abundance as: Mg2+ > Ca2+ > Na+ > K+ and HCO3  > SO4 2− > Cl > NO3  > F, respectively. Elevated SO4 2− concentrations in the Gopalichuck, Kendwadih, and Kachhi-Balihari mine waters are attributed to pyrite weathering. The water quality assessment indicated that TDS, hardness, Mg2+, and SO4 2− are the major parameters of concern in the study area. Except for Fe, all of the measured metals in the mine water were well within the levels recommended for drinking water. With only a few exceptions, the mine water is of good to permissible quality and suitable for irrigation.  相似文献   
8.
Economic models of urban spatial patterns have largely ignored complexity as an attribute of urban systems. Complexity theorists on the other hand have not made sufficiently serious and sustained attempts to verify empirically the relevance of complex systems models for urban spatial patterns. This research bridges this gap by simulating the evolution of an urban employment pattern as a self-organizing complex system and seeking its empirical validation. It estimates the model’s parameters by using firm data aggregated to the level of municipalities in Cleveland-Akron Consolidated Metropolitan Statistical Area in Ohio. The interaction among four parameters, forces of attraction and dispersion and their respective rates of dissipation with distance, are modeled as a two-dimensional complex system. The research compares the states of the modeled system with empirical data to present viable methods for verification, calibration and validation of such models.
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9.
A series of Er~(3+) ions doped lithium lead alumino borate(LiPbAlB) glasses were synthesized via melt quench method and their structural,physical and optical properties were studied.Judd-Ofelt theory in correlation with the emission and absorption profiles was performed for the measurement of various radiative parameters for different transitions of Er~(3+) doped glasses.The as-prepared glasses show deep green(550 nm) as well as NIR(1532 nm) emission at 380 and 980 nm excitation wavelengths,respectively.The intensity of emission spectra increases with Er~(3+) ions concentration up to 1.5 mol% and beyond quenching is observed.The Dexter theory applied to the emission profiles reveals the interaction between Er~(3+)ions as dipole-dipole in nature.CIE color coordinates are found to fall in the green region of the visible spectrum.It is observed that 1.5 mol% of Er~(3+) ions concentration is optimum to exhibit the maximum quantum efficiency,branching ratios,gain bandwidth,emission cross-section,gain crosssection and aptly suitable for visible and NIR photonic applications.  相似文献   
10.
The poly(vinyl chloride) (PVC) industry plays an important role in today's total plastics industry. The major volume of PVC is used as soft and plasticized PVC. PVC applications consume approximately 80% of the total production of plasticizers. Most of the common plasticizers are aromatic esters of phthalic acid. In the majority of countries, phthalate plasticizers are banned due to their carcinogenic properties. The concern raised about toxicity led to a large demand for bio‐based non‐toxic plasticizers. Hence, there is an increasing interest in replacing the phthalate plasticizers with those produced from simple bio‐based materials. Dehydrated castor oil fatty acid (DCOFA) is a renewable resource which can be esterified and used as an environment friendly plasticizer for PVC. Benzyl ester (BE) was prepared by reacting DCOFA with benzyl alcohol in the presence of catalyst at 170–180 °C. Esterification was further confirmed by acid value, hydroxyl number, 1H NMR and Fourier transform IR spectroscopy. The modified plasticizer was used in various proportions as a co‐plasticizer in PVC for partial replacement of dioctyl phthalate (DOP). With an increase in the proportion of BE in PVC samples, a good plasticizing performance was observed. The incorporation of BE also resulted in a reduction in viscosity and viscosity pick‐up and improved mechanical, exudation, thermal degradation and chemical resistance properties. The presence of BE showed a reduction in the whiteness index due to presence of conjugated double bonds in the structure. The results of DSC, XRD and Shore hardness studies showed no significant variation in properties compared with those of DOP‐plasticized sheets and thus we can conclude that BE can be used as a co‐plasticizer in PVC. © 2013 Society of Chemical Industry  相似文献   
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