Constructing secure content-dependent watermarking scheme using homomorphic encryption

Proceedings of the 2007 IEEE International Conference on Multimedia and Expo, ICME 2007627-63

A green separation mode of synephrine from Citrus aurantium L. (Rutaceae) by nanofiltration technology

Thermal breakage of alkaloid ingredients was a common problem to which attention should be paid in the application of fruit ingredients separation. In this study, the mathematical models were established to predict the rejection of synephrine from Citrus aurantium L. (Rutaceae). The experiment showed that there was a linear relationship between operation pressure and membrane flux. Meanwhile, under the influence of solution–diffusion effect and the charge effect, the mass transfer coefficient was power functioned with initial concentration. The mathematical model showed that the predicted rejections of synephrine from Citrus aurantium extract were well approximate to real ones, and the lipid-lowering active ingredient had effectively enriched. The predicted model of nanofiltration separation has a preferable applicability to synephrine and provides references for nanofiltration separation, especially for raw food materials with synephrine

A green separation mode of synephrine from Citrus aurantium

Thermal breakage of alkaloid ingredients was a common problem to which attention should be paid in the application of fruit ingredients separation. In this study, the mathematical models were established to predict the rejection of synephrine from Citrus aurantium L. (Rutaceae). The experiment showed that there was a linear relationship between operation pressure and membrane flux. Meanwhile, under the influence of solution–diffusion effect and the charge effect, the mass transfer coefficient was power functioned with initial concentration. The mathematical model showed that the predicted rejections of synephrine from Citrus aurantium extract were well approximate to real ones, and the lipid-lowering active ingredient had effectively enriched. The predicted model of nanofiltration separation has a preferable applicability to synephrine and provides references for nanofiltration separation, especially for raw food materials with synephrine

Ultrasonic-assisted activated carbon separation removing bacterial endotoxin from salvia miltiorrhizae injection

Ultrasonic-assisted activated carbon separation (UACS) was first employed to improve product quality by regulating adsorption rate and removing bacterial endotoxin from salvia miltiorrhizae injection. The adsorption rate was related to three variables: activated carbon dosage, ultrasonic power, and pH. With the increase of activated carbon dosage from 0.05 % to 1.0 %, the adsorption rates of salvianolic acids and bacterial endotoxin increased simultaneously. The adsorption rates at which bacteria endotoxins increased from 52.52 % to 97.16 % were much higher than salvianolic acids. As the ultrasonic power increased from 0 to 700 W, the adsorption rates of salvianolic acids on activated carbon declined to less than 10 %, but bacterial endotoxin increased to more than 87 %. As the pH increased from 2.00 to 8.00, the adsorption rate of salvianolic acid dropped whereas bacterial endotoxin remained relatively stable. On the basis of response surface methodology (RSM), the optimal separation conditions were established to be activated carbon dose of 0.70 %, ultrasonic power of 600 W, and pH of 7.90. The experimental adsorption rates of bacterial endotoxin were 94.15 %, which satisfied the salvia miltiorrhizae injection quality criterion. Meanwhile, salvianolic acids' adsorption rates were 1.92 % for tanshinol, 4.05 % for protocatechualdehyde, 2.21 % for rosmarinic acid, and 3.77 % for salvianolic acid B, all of which were much lower than conventional activated carbon adsorption (CACA). Salvianolic acids' adsorption mechanism on activated carbon is dependent on the component's molecular state. Under ideal separation conditions, the molecular states of the four salvianolic acids fall between 1.13 % and 6.60 %. The quality of salvia miltiorrhizae injection can be improved while maintaining injection safety by reducing the adsorption rates of salvianolic acids to less than 5 % by the use of ultrasound to accelerate the desorption mass transfer rate on the activated carbon surface. When activated carbon adsorption was used in the process of producing salvia miltiorrhizae injection, the pH of the solution was around 5.00, and the proportion of each component's molecular state was tanshinol 7.05 %, protocatechualdehyde 48.93 %, rosmarinic acid 13.79 %, and salvianolic acid B 10.28 %, respectively. The loss of useful components was evident, and the corresponding activated carbon adsorption rate ranged from 20.74 % to 41.05 %. The average variation rate in plasma His and IgE was significant (P  0.05). The ultrasonic at a power intensity of 60 W/L and the power density of 1.20 W/cm2 may resolve the separation contradiction between salvianolic acids and bacterial endotoxin, according to experiments conducted with UACS at different power intensities. According to this study, UACS has a lot of potential applications in the pharmaceutical manufacturing industry and may represent a breakthrough in the field of ultrasonic separation

Nanosecond pulse-driven atmospheric-pressure plasmas for polymer surface modifications: Wettability performance, insulation evaluation and mechanisms

Epoxy resin (EP) is one of the most widely-used insulating support materials in electrical power systems, with its insulating performance playing an important role in high-voltage engineering. In this study, a nanosecond pulse-driven Ar/Octamethylcyclotetrasiloxane (OMCTS) plasma jet is developed for fabricating nanocomposite dielectric materials to enhance their EP properties. It is demonstrated that the plasma-enabled polymerization effectively modifies the physical morphology and chemical composition of EP surfaces, where the surface roughness greatly increases with the deposition of less-polar silicon-containing films. Moreover, with an increased OMCTS carrier gas flow rate, the surface conductivity of the EP increases by two orders of magnitude, which is directly related to the appearance of shallow traps in the dielectric surface after Ar/OMCTS plasma treatment. Results show that the trap depth of the electron decreases from 1.21 to 0.99 eV post-treatment, with the OMCTS fragments becoming shallow trap points for charge detrapping and transportation processes. Moreover, the addition of a controlled amount of OMCTS increases the plasma discharge intensity, promotes silicon film deposition, and thus significantly improves the insulation and wettability performance, with higher flashover voltages and water contact angles (WCA). By contrast, excessive addition of OMCTS inhibits the plasma discharge due to the absorption and consumption of energetic electrons by OMCTS molecules. Quantum chemistry calculations are further developed to explore the mechanisms of plasma-induced surface modifications. Overall, the proposed plasma polymerization strategy offers a promising fabrication technique and provides guiding insights into the fabrication of nanocomposite dielectric materials in electrical engineering.</p

Plasma-electrified repair of damaged polymer composites for surface crack healing and insulation recovery

Polymer composites, widely used in aerospace and electrical power systems, are inevitably aged by environmental stress causing cracks on the material's surface, which weakens their mechanical and electrical properties. Addressing the issue requires significant effort and the use of hazardous chemicals. In this study, a novel plasma-electrified repair method based on the Ar/H2O/alkoxysilane (PMDMS) low temperature plasma is developed for the surface crack healing and insulation recovery of silicone rubber (SIR) composites. It is demonstrated that the plasma-enabled polymerization effectively repairs the cracked SIR, with a new fin-like insulating layer deposited on the crack surface. The mechanical and electrical properties of the cracked SIR are improved after the plasma repair, with the result clearly better than using the conventional coating method. Hydrolysis-condensation of PMDMS by plasma-enabled dissociation and re-assembly, surface activation of the crack by plasma modification and grafting-crosslinking in the crack account for the multiphase chemical reactions induced within the crack. Further analysis based on quantum chemistry calculations reveals that the plasma treatment both promotes the chemical reactivity of the SIR surface and reconstructs a dense repair phase in the crack with a wide forbidden gap and shallow taps, further confirming this effective crack healing process which improves the mechanical and electrical performances of the damaged SIR. Overall, this newly-developed plasma-electrified repair method for damaged SIR eliminates the environmental pollution caused by large scale and overused chemical coatings, and offers new possibilities for sustainable and low-carbon-emission material engineering for processing and restoration of composite materials.</p