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An ecofriendly and biodegradable porous structure was prepared from drying aqueous foams based on nano fibrillated cellulose (NFC), extracted from softwood pulp by subcritical water/CO2 treatment (SC-NFC). The primary aim of this work was to use the modified SC-NFC as stabilizer for a water-based Pickering emulsion which upon drying, yielded porous cellulosic materials, a good dye adsorbent. In order to exploit the carboxymethylated SC-NFC (CMSC-NFC, with a degree of substitution of 0.35 and a charge density of 649 μeqv/g) as a stabilizer for water-based Pickering emulsion in subsequent step, an optimized quantity of octyl amine (30 mg/g of SC-NFC) was added to make them partially hydrophobic. A series of dry foam structures were prepared by varying the concentrations of treated CMSC-NFCs and 4 wt% was found to be the optimum concentration to yield foam with high porosity (99%) and low density (0.038 g/cc) along with high compression strength (0.24 MPa), superior to the conventionally extracted NFC. The foams were applied to capture as high as 98% of methylene blue dyes, making them a potential green candidate for treating industrial effluent. In addition, the dye adsorption kinetics and isotherms were found to be well suited with second order kinetics and Langmuir isotherm models. 相似文献
3.
Pattern Analysis and Applications - Rare association rule mining is an imperative field of data mining that attempts to identify rare correlations among the items in a database. Although numerous... 相似文献
4.
Ramasubba Reddy Palem Ganesh D. Shimoga Zuzana Kronekova Monika Sláviková Petr Saha 《国际聚合物材料杂志》2018,67(1):1-10
Chitosan–silver nanocomposites (CS-HDA-AgNCs) was prepared using chitosan, biogenic silver nanocomposites, and crosslinker, hexamethylene 1,6-di(amino carboxysulfonate) (HDA). The film is flexible and transparent. Its physical, mechanical, thermal, hydrophilicity, and swelling properties were improved by HDA (2.5%). The antimicrobial activity of CS-HDA-AgNCs were not displayed any remarkable zone of inhibition but showed toxic effect in the presence of normal 3T3 fibroblasts and cancer HeLa cells. It decreases to ca. 5–7% for both cell lines. In conclusion, it can be mentioned that the CS-HDA-AgNCs, a kind of new functional biomaterial, could be useful for health-care applications. 相似文献
5.
Volker Kahlenberg Johan P.R. de Villiers Dirk Odendaal Hannes Krüger Shengqiang Song Mithun Nath 《Journal of the American Ceramic Society》2019,102(11):6968-6979
Polycrystalline material of a novel phase in the system CaO–Al2O3–Cr2O3 has been obtained by solid-state reactions. Chemical analysis indicated the composition CaAl2Cr2O7. Single-crystal growth of the new compound using borax as a mineralizer was successful. Diffraction experiments at ambient conditions on a crystal with composition CaAl2.13Cr1.87O7 yielded the following basic crystallographic data: space group P 3, a = 7.7690(5) Å, c = 7.6463(5) Å, V = 399.68(6) Å3, Z = 3. Structure determination and subsequent least-squares refinements resulted in a residual of R(|F|) = 2.3% for 1440 independent observed reflections and 113 parameters. To the best of our knowledge, the structure of CaAl2.13Cr1.87O7 or CaAl2Cr2O7 represents a new structure type. It belongs to the group of double layer structures where individual double layers contain octahedrally and tetrahedrally coordinated cation positions. Linkage between neighboring sheet packages is provided by additional calcium cations. Furthermore, thermal expansion has been studied in the interval between 29 and 790°C using in situ high-temperature single-crystal diffraction. No indications for a structural phase transition were observed. From the evolution of the lattice parameters the thermal expansion tensor has been obtained. A pronounced anisotropy is evident. The response of structural building units to variable temperature has been discussed. 相似文献
6.
Rewari Sonam Nath Vandana Haldar Subhasis Deswal S. S. Gupta R. S. 《Microsystem Technologies》2019,25(5):1537-1546
Microsystem Technologies - In this paper a cylindrical Dual Metal (DM) Dielectric Engineered (DE) Gate All Around (GAA) MOSFET has been proposed to resolve a big issue of Gate Inducted Drain... 相似文献
7.
Wireless Personal Communications - Detection of heart sound and analysis is required to determine heart rate, heart sound components (S1, S2 and murmurs), and is an important step to... 相似文献
8.
Mohd Danish Turnad Lenggo Ginta Khairul Habib Ahmad Majdi Abdul Rani Bidyut Baran Saha 《传热工程》2019,40(12):1023-1032
ABSTRACTA combined analytical and experimental study was carried out to analyze the effects of cryogenic cooling on temperature during turning of AZ31C magnesium alloy. Finite element method was employed to model and simulating the cryogenic and dry turning. Results obtained from the model were found to be in good agreement with the experimental observations. For the maximum temperature at the turned surface, the difference in the experimental and predicted value observed during dry and cryogenic turning was only 4 and 8% respectively. A significant reduction in the maximum temperature on the chip surface (around 35%) and tool surface (around 29%) was observed during the cryogenic turning compared to dry turning. This reduction in temperature was an attribute of liquid nitrogen, which produces intense cooling effect around the vicinity cutting zone where heat generation takes place hence enhancing the heat transfer. The isothermal region belonging to the highest temperature on the tool surface was also reduced by about 42%. The reduction in temperature during cryogenic conditions were found to be beneficial for the machining of magnesium alloys under safe conditions, reducing the risk of ignition and explosions, and also increases the sustainability of the process. 相似文献
9.
Darothi Bairagi Venkataramana Munukuti Pallabi Bhuyan Rajib Saha Sumantra Mandal 《工业材料与腐蚀》2021,72(5):829-838
The influence of cementite spheroidization on the impact toughness and electrochemical properties of a high-carbon steel has been thoroughly investigated in this study. Heavy warm rolling, followed by 2 h of annealing, has resulted in near-complete spheroidization, leading to a microstructure consisting of nano-cementite globules dispersed in the ultrafine-grained ferritic matrix. The Charpy impact test exhibited superior impact toughness with increased spheroidization. It is validated by the presence of abundant dimples in the fractographs of spheroidized specimens, in contrast to the as-received one that experienced a brittle failure due to its lamellar pearlitic structure. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) carried out in a 3.5% NaCl solution revealed that the corrosion resistance of the alloy gets improved with the increase in the degree of spheroidization. This is attributed to the lower susceptibility of the spheroidized specimen to microgalvanic corrosion owing to the minimum area of contact between nano-spheroidized cementite and ferrite, as elucidated with the help of EIS results aided by equivalent electrical circuit model. 相似文献
10.
In the recent sub-20 nm technology node, the process variability issues have become a major problem for scaling of MOS devices. We present a design for a strained Si/SiGe FinFET on an insulator using a 3D TCAD simulator. The impact of metal gate work function variability (WFV) on electrical parameters is studied. Such impact of WFV for different mole fractions (x) of the SiGe layer in a strained SOI-FinFET with varying grain size is presented. The results show that as the mole fraction is increased, the variability in threshold voltage (σVT) and off current (σIoff) is decreased; while, the variability of on-current (σIon) is increased. A notable observation is the distribution of electrical parameters approaches a normal distribution for smaller grain sizes. 相似文献