Optically tuned and large-grained bromine doped CH3NH3PbI3 perovskite thin films via aerosol-assisted chemical vapour deposition

Herein, doping of methylammonium lead iodide perovskite thin films with bromine ions is successfully performed for the first time using the aerosol-assisted chemical vapour deposition process. Depending on the doping levels, photoluminescence spectra are shifted relative to their bandgap values. Detailed analysis of scanning electron microscope images showed that increasing the bromine levels linearly increased the grain sizes. The unchanged amount of detected lead provided evidence for the controlled processing conditions. Both bulk and surface compositional techniques confirmed the deposition of marginally iodine rich perovskite thin films

Protective potential of methanol extract of Digera muricata on acrylamide induced hepatotoxicity in rats

This study was aimed to evaluate the probable protective effects of Digera muricata methanol extract (DME) against acrylamide (AA) induced hepatocellular injuries in female Sprague-Dawley rat. Phytochemical screening for the presence of different bioactive chemical groups was also carried out. The daily dose (6 mg/kg bw i.p.) injection of AA for 15 days caused significant increase in serum level of liver marker enzymes and metabolites: AST, ALT, ACP, ALP, LDH, BUN, creatinine, direct bilirubin and total bilirubin, while significant decrease in total protein and albumin. Hepatic level of antioxidant enzymes; CAT, POD, SOD, GSH-Px, GST and QR, and GSH contents were significantly decreased, while γ-GT and MDA was significantly increased. Treatment of DME (100, 150 and 200 mg/kg), dose dependently, ameliorated the toxicity of AA and the studied parameters were reversed towards the control level. Hepatic lesions induced with AA were reduced with DME treatment. Phytochemical screening indicates the presence of flavonoids, alkaloids, terpenoids, saponins, tannins, phlobatanin, coumarins, anthraquinones and cardiac glycosides. Total phenolic and flavonoids contents were 205±0.23 and 175.0±0.65 mg/g as equivalent to gallic acid and rutin, respectively in DME. In conclusion, the results suggest that the hepatoprotective effects of DME against AA-induced oxidative injuries could be attributed to the phenolics and flavonoids.Key words: Digera muricata, acrylamide, alanine aminotransferase, antioxidant enzymes, TBARS, flavonoids

Improved FTO/NiOx interfaces for inverted planar triple cation perovskite solar cells

Front electrodes of fluorine doped tin oxide (FTO) thin films and hole transporting layers of nickel oxide thin films have been combined to fabricate 1.063 cm2 inverted planar solar cells with cesium-containing triple cation perovskites as absorber layers. Using atmospheric pressure chemical vapor deposition FTO layers were obtained with low sheet resistance, decreased root mean squareroughness, increased transmission,and reduced optical haze values compared to a widely used commercial FTO substrate. Cell performance outperformed the equivalent cells fabricated using the commercial FTO. With full illumination under maximumpowerpoint tracking, a stabilized power conversion efficiency of 13.78 % was obtained for the champion device

Longterm Effect Of Phenytoin On Lipid Profile Parameters In Epileptic Patients

Research Problem: What are the factors responsible for decreased incidence of coronary artery disease in epileptics? Objectives: To evaluate the effect of phenytoin on lipid profile parameters in epileptics and to discuss its implications. Study Design: Prospective study. Setting: Neurology clinic of Medicine Department of a teaching hospital. Participants: Randomly selected epileptic patient at­tending neurology clinic and admitted to inpatient department of J. N. Medical College Hospital. Sample Size: 56 epileptic patients. Study Variables: Phenytoin therapy, lipid profile pa­rameters. Statistical Analysis: By test of significance. Result: No significant change in serum levels of total cholesterol, LDL - C, VLDL - C, triglycerides and phospholipids was observed with phenytoin therapy during study. However, serum HDL - C showed a significant increase, both at 12 weeks and 24 weeks ( P < 0.001) of therapy. Conclusion: Phenytoin,    a    commonly used anticonvulsive drug, increases serum HDL - C level significantly, while there is no significant change in other parameters of lipid profile. This rise in HDL - C may provide protection to epileptic patients against atherogenic vascular diseases including coronary ar­tery disease

An intrusion and fault tolerant forensic storage for a SIEM system

Current Security Information and Events Management (SIEM) solutions lack a data storage facility which is secure enough - i.e. stored events related to security incidents cannot be forged and are always available - that it can be used for forensic purposes. Forensic storage used by current SIEM solutions uses traditional RSA algorithm to sign the security events. In this paper we have analyzed the limits of current forensic storages, and we have proposed an architecture for forensic storage, implementing a threshold-based variant of the RSA algorithm, that outperforms state of the art SIEM solutions in terms of intrusion- and fault-tolerance. We show by experiments that our forensic storage works correctly even in the presence of cyber-attacks, although with a performance penalty. We also conduct an experimental campaign to evaluate the performance cost of the proposed scheme as a function of the threshold

1 cm2 CH3NH3PbI3 mesoporous solar cells with 17.8% steady-state efficiency by tailoring front FTO electrodes

In this article, we investigate the effects of atmospheric-pressure chemical vapour deposited fluorine doped tin oxide (FTO) thin films as front electrodes for the fabrication of mesoporous perovskite solar cells with an active area of 1 cm2 and compare them with the use of a commonly used commercial transparent conducting oxide. The effects of sheet resistance (Rs) and surface roughness are both closely linked to the film thickness. In order to separate out these effects the characteristics of the deposited FTOs were carefully controlled by changing the fluorine doping levels and the number of passes under the coating head to give films of specific thicknesses or Rs. Under AM 1.5 Sun illumination and maximum power point tracking, the optimised FTOs yielded a steady-state power conversion efficiency of 17.8%, higher than that of the reference cell fabricated from the commercial FTO. We attribute the improved cell efficiency to increased fill factor and a lower series resistance resulting from the lower Rs and increased thickness of these FTO substrates. This low-cost and viable methodology is the first such type of study looking independently at the significance of FTO roughness and resistance for highly efficient mesoporous perovskite solar cells

Growth patterns and properties of aerosol-assisted chemical vapor deposition of CH3NH3PbI3 films in a single step

In this work, we highlight growth patterns and properties of aerosol-assisted chemical vapor deposition of perovskite, CH3NH3PbI3 thin films. The substrates were distinctly covered with both perovskite and lead iodide thin films which we attribute to methylammonium iodide being the rate limiting step via mass transport. The black perovskite films demonstrated strong absorption and photoluminescence properties confirming their suitability as a light absorbing material for the fabrication of solar cells. Scanning electron microscope images showed dense morphologies along with the confirmation of holes and gaps at reduced growth temperature

Measuring Coulomb and Viscous Friction in Revolute Joint

In this research work, the emphasis is on the study of the effects of friction in the revolute joint for fine manipulation of robotic arm manipulators. The friction model is used to capture the friction in static mode, the breakaway point of displacement and the linear part of the friction when asperity junctions arc broken. The experimental setup is designed to attain Coulomb and viscous friction parameters in the revolute joint with velocity sensor equipped with mechanical system. The velocity sensor detects velocity response as controlled ramp torque is applied to the physical model to evaluate friction in the joint. The physical model is designed and built in MSC ADAMS environment and simulated using the same parameters which were experienced by the real model. The block diagram is drawn in the Simulink: (MATLAB) under same configuration and then simulated. The results, obtained from MSC ADAMS and Simulink, are compared with the experimental data