•Thin layers of anatase titanium dioxide were coated on glass by spray pyrolysis method.•The layers were hydrogenated by DC plasma from room temperature up to 350°C.•Band gap of the layers was ...decreased 0.13eV by plasma treatment at highest temperature.•There is a specific plasma temperature range, which hydrophilicity and photocatalytic properties of the layers are optimum.
Thin layers of anatase titanium dioxide were coated on glass by spray pyrolysis method. The layers were hydrogenated by DC plasma from room temperature up to 350°C. Hydrogen plasma treatment at low temperatures, leads to decrease the surface roughness, while surface roughness is increased by enhancing plasma temperature. Layers’ band gap was decreased 0.13eV by plasma treatment at highest temperature. Hydrophilicity and photocatalytic properties of the layers under plasma treatment at 150 and 200°C, were improved noticeably. However, plasma treatment at temperatures above 200°C was lead to decrease hydrophilicity and photocatalytic activity of TiO2 layers. The reason seems formation of oxygen vacancies in the interior layers that act as charge carriers’ recombination centers.
•Thin films of YBCO were fabricated by PLD technique on LAO substrate.•A filter pattern was designed and implemented by wet photolithography method on the films.•Characterization of the filter at ...77 K has been compared with the simulation results and the results for a made gold filter.
Epitaxial thin films of YBCO high temperature superconductor are widely used in telecommunication technology such as microwave filter, antenna, coupler and etc., due to their lower surface resistance and lower microwave loss than their normal conductor counterparts. Thin films of YBCO were fabricated by PLD technique on LAO substrate. Transition temperature and width were 88 K and 3 K, respectively. A filter pattern was designed and implemented by wet photolithography method on the films. Characterization of the filter at 77 K has been compared with the simulation results and the results for a made gold filter. Both YBCO and gold filters show high microwave loss. For YBCO filter, the reason may be due to the improper contacts on the feedlines and for gold filter, low thickness of the gold film has caused the loss increased.
The normal state resistivities of single phase polycrystalline Gd(Ba2 - xPrx)Cu3O7 + Delta *d and (Gd1 - xPrx)Ba2Cu3O7 - Delta *d samples with x = 0.,0.0,0.10, and 0.15 were investigated. The ...bipolaron model can explain properly the normal state resistivity of the samples. Gd(Ba2 - xPrx)Cu3O7 + Delta *d samples for the special cases x = 0.1 and 0.15 show different behavior. Based on some previous evidence, this behavior could originate from mis-substitution of Ba atoms at rare earth sites. In Gd(Ba2 - xPrx)Cu3O7 + Delta *d samples, the number of localized carriers increases faster than in (Gd1 - xPrx)Ba2Cu3O7 - Delta *d samples with Pr doping. This shows that the superconductivity suppression by Pr at the Ba site is more destructive than by Pr at the rare earth site.
YBa2Cu3O7 (Y123) and Y3Ba5Cu8O18 (Y358) thin films were deposited by pulsed laser deposition method. XRD analysis shows both films grow in c axis orientation. Resistivity versus temperature analysis ...shows superconducting transition temperature was about 91.2 K and 91.5 K and transition width for Y358 and Y123 films was about 0.6 K and 1.6 K, respectively. Analysis of the temperature dependence of the AC susceptibility near the transition temperature, employing Bean's critical state model, indicates that intergranular critical current density for Y358 films is more than twice of intergranular critical current density of Y123 films. Thus, flux pining is stronger in Y358 films. Weak links in the both samples is of superconductor-normal-superconductor (SNS) type irrespective of stoichiometry.
•YBa2Cu3O7 (Y123) and Y3Ba5Cu8O18 (Y358) thin films were deposited by pulsed laser deposition method.•Resistivity versus temperature analysis shows superconducting transition temperature was about ...91.2 K and 91.5 K and transition width for Y358 and Y123 films was about 0.6 K and 1.6 K, respectively.•Analysis of the temperature dependence of the AC susceptibility near the transition temperature, shows that flux pining is stronger in Y358 films.
YBa2Cu3O7 (Y123) and Y3Ba5Cu8O18 (Y358) thin films were deposited by pulsed laser deposition method. XRD analysis shows both films grow in c axis orientation. Resistivity versus temperature analysis shows superconducting transition temperature was about 91.2 K and 91.5 K and transition width for Y358 and Y123 films was about 0.6 K and 1.6 K, respectively. Analysis of the temperature dependence of the AC susceptibility near the transition temperature, employing Bean's critical state model, indicates that intergranular critical current density for Y358 films is more than twice of intergranular critical current density of Y123 films. Thus, flux pining is stronger in Y358 films. Weak links in the both samples is of superconductor-normal-superconductor (SNS) type irrespective of stoichiometry.
YBa
2
Cu
3
O
7−
δ
(YBCO) thin films were deposited by pulsed laser deposition on single-crystal LaAlO
3
(100) substrates in O
2
partial pressure (
P
O2
) from 400 to 500 mTorr. The XRD data shows the ...presence of
a
-axis-oriented grains in the YBCO films deposited at
P
O2
= 500 mTorr. The
a
-axis grains lead to increase of strain. Atomic force microscopy images show as oxygen pressure has increased, average surface roughness of the films and size of droplets were increased. The grain misorientaion could be the reason for high average roughness. However, surface analysis by statistical methods reveals that three surfaces have multi-affine structure irrespective of oxygen pressure. Analysis of the temperature dependence of the AC susceptibility near the transition temperature indicates that with increasing oxygen pressure, intergranular critical current density has decreased. It is also suggested that the nature of weak links in the samples is of superconductor-normal-superconductor (SNS) type irrespective of the oxygen pressure.
Background/Aims: Global incidence of hypertension is estimated to be, in excess of, one billion people, and given the efficacy of soluble dietary fibers, in particular, Psyllium, to positively impact ...blood pressure in patients with hypertension, it is of clinical importance that consensus on its supplementation be established. Therefore, the aim of the study was systematically review and meta-analyze the effect of psyllium supplementation on blood pressure of hypertensive patients in randomized controlled trials.
Methods: We searched six universal databases including; Pubmed/Medline, Ovid, Cochrane Library, Google Scholar, Embase, and Scopus until November 2018. Both combined and stratified analyzes were conducted. A fixed-effects or random-effects model was used to assess the mean effect sizes.
Results: An eventual 11 trials with 592 participants were considered as eligible for inclusion in the present meta-analysis. The meta-analysis revealed a significant reduction of 2.04 mmHg in systolic blood pressure (weighted mean difference, -2.04; 95% confidence interval, -2.82 to -1.63; p < 0.001). Whilst meta-regression highlighted that the hypotensive effect of psyllium was stronger in subjects with higher baseline blood pressure.
Conclusions: Given the overarching benefits and lack of reported side effects, particularly for hypertensive patients, health care providers and clinicians should consider the use of psyllium supplementation for the treatment or abatement of hypertension, or hypertensive symptoms.
Steganography is an appropriate approach to establish a secure connection between the sender and the receiver. Data embedding in Discrete Cosine Transform (DCT) coefficients for JPEG images is one of ...the most practical approaches nowadays. In this paper, a new method called GA-Shield is proposed, in which, instead of using fixed embedding capacity, embedding a different number of bits in the quantized DCT coefficients according to the magnitude of the coefficient is used to spread bits of secret message in the most suitable coefficients. In addition, this method uses a genetic algorithm to minimize the distortion due to embedding. This minimization is performed by deciding on the best formula to calculate coefficient value after embedding. In this phase, PSNR is used as the metric to measure the amount of distortion in the cover image to produce the stego image. As these changes decrease, the value of PSNR would be optimized, and the stego image would have better quality. The proposed method can embed 300 to 20,000 bits of data (on average) in the cover image and produce the stego image with a PSNR value in the range of 65 to 40 and a SSIM value of more than 0.985. The consequences of comparisons with the state-of-the-art show that despite the fact that the proposed technique has less embedding capacity than some of the current ones, the superiority of stego image quality and security of the proposed technique, mainly at low embedding levels, is significant.
