The paper reports the electrodeposition of polypyrrole thin film by galvanostatic mode of deposition. The structural study of polypyrrole film is characterized by X-ray diffraction (XRD) and Fourier ...transforms infrared (FTIR) spectroscopy. The surface morphological study is carried out with scanning electron microscope (SEM) techniques. The XRD and FTIR spectroscopy study shows the formation of amorphous and conducting polypyrrole thin film. SEM images shows that the substrates are uniformly coated with polypyrrole thin films. The surface wettability study is carried out by means of contact angle measurement. Surface wettability study shows that the films are
hydrophilic
in nature. The testing of polypyrrole film electrode as a supercapacitor is made with the help of cyclic voltammetry, galvanostatic charge–discharge measurement and electrochemical impedance spectroscopy study. The value of specific capacitance was found to be 381 F g
−1
in 0.5 M Na
2
SO
4
aqueous solution at scan rate 5 mV s
−1
in the −1.0 to +1.0 V versus saturated calomel electrode. However, the value of Coulombic efficiency, specific energy and specific power of polypyrrole thin film electrode is observed to be 96.54 %, 762.60 Wh kg
−1
and 281,000 kW kg
−1
.
The PathoSystems Resource Integration Center (PATRIC) is one of eight Bioinformatics Resource Centers (BRCs) funded by the National Institute of Allergy and Infection Diseases (NIAID) to create a ...data and analysis resource for selected NIAID priority pathogens, specifically proteobacteria of the genera Brucella, Rickettsia and Coxiella, and corona-, calici- and lyssaviruses and viruses associated with hepatitis A and E. The goal of the project is to provide a comprehensive bioinformatics resource for these pathogens, including consistently annotated genome, proteome and metabolic pathway data to facilitate research into counter-measures, including drugs, vaccines and diagnostics. The project's curation strategy has three prongs: 'breadth first' beginning with whole-genome and proteome curation using standardized protocols, a 'targeted' approach addressing the specific needs of researchers and an integrative strategy to leverage high-throughput experimental data (e.g. microarrays, proteomics) and literature. The PATRIC infrastructure consists of a relational database, analytical pipelines and a website which supports browsing, querying, data visualization and the ability to download raw and curated data in standard formats. At present, the site warehouses complete sequences for 17 bacterial and 332 viral genomes. The PATRIC website (https://patric.vbi.vt.edu) will continually grow with the addition of data, analysis and functionality over the course of the project.
In the present work flower like Mn-Co mixed metal oxide electrode materials were successfully synthesized by simple, low cost electrodeposition method on stainless steel substrates. Different volume ...ratio of Mn-Co was used to attempt enhancement in the supercapacitive properties of electrode material. Structural, morphological and wettability properties of synthesized electrodes were carried out using XRD, RAMAN, FE-SEM and Contact Angle Measurement techniques. Electrochemical properties of electrodeposited Mn-Co mixed metal oxide at three different volume variation such as 50-50, 60-40 and 70-30 electrodes were analyzed by using cyclic voltammetry, galvonostatic charge discharge and electrochemical impedance spectroscopy in 1 M NaOH aqueous electrolyte. The Mn-Co:60-40 composition shows maximum specific capacitance which is 679 F/g at scan rate 5 mV/sec. Charge discharge studies gives 95% columbic efficiency. Impedance spectroscopy reveals capacitive behavior and gives series resistance ∼0.19 ohm and combined internal resistance ∼0.89 ohm. The 80% retention of specific capacitance after the 1000 cycles. The synergistic effect of Mn-Co mixed metal oxide electrode having good conductivity, large surface area and improved charge transportation than individual electrode material leads to enhancing supercapacitor performance of electrode material for its practical application.
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•Mn-Co mixed metal oxide electrode materials.•Flower like morphology, High hydrophilicity.•High specific capacitance 679 F/g at scan rate 5 mV/sec and long cycle life.•Synergic effect of Mn-Co mixed metal oxide composite with improved supercapacitive properties of electrode material.
The present paper report a study of the nickel doped cobalt ferrite Co
0.9
Ni
0.1
Fe
2
O
4
have been synthesized by conventional hydrothermal technique followed by microwave sintering. The Co
0.9
Ni
...0.1
Fe
2
O
4
nanoparticles are characterized by X-ray diffraction (XRD), transmission electron microscopy, field emission scanning electron microscopy, particle size analyzer and vibrating sample magnetometer. The XRD spectra show a high degree of crystallinity and also indicates that the diffraction peaks correspond to the cubic spinel structure. Transmission electron microscopy indicating that, the crystallite size of Co
0.9
Ni
0.1
Fe
2
O
4
nanoparticles was in the range of 40–75 nm. The nanoparticles show relatively high saturation magnetization of 32.540 emu/g.
Series of the ferrite samples with a chemical formula Ni0.7Zn0.3CrxFe2−xO4 (x=0.0–0.5) were prepared by a sol–gel auto-combustion method and annealed at 600°C for 4h. The prepared samples have the ...cubic spinel structure with no impurity phase. As the Cr3+ content x increases, the unit cell dimensions decrease with an increase in Cr3+ content x. The crystallite size is decreases from 37nm to 21nm as the Cr3+ content increases from x=0.0 to 0.5. Resistivity increases whereas dielectric constant decreases with an increase in Cr3+ content x. Maxima in the dielectric loss tangent versus frequency appear when the frequency of the hopping charge carriers coincides with the frequency of the applied alternating field. Dielectric constant and dielectric loss tangent increases with increase in temperature. Saturation magnetization of sintered samples showed higher values as compared to as-prepared sample. Curie temperature deduced from AC susceptibility data decreases with increasing x.
Transition metal chalcogenides are gaining attraction in the emerging energy-storing field owing to their captivating properties. Molybdenum disulfide (MoS2) was deposited on Ni foam by using a ...one-step electrodeposition method. X-ray diffraction study showed that the deposited MoS2 was amorphous, and X-ray photoelectron spectroscopy confirms the presence of Mo and S in the 4+ and 2+ oxidation states. Different nanostructures were observed by varying the deposition time, and MoS2 deposited for 300 s has an interconnected crumpled-nanoflake structure. The electrochemical performance of MoS2 electrodes was investigated between 0.2 and 1 V vs. SCE potential in 1M Na2SO4 electrolyte and the interconnected crumpled-nanoflake structure showed a maximum areal capacitance of 416.9 mFcm−2 at a current density of 1 mAcm−2. The charge storage kinetics of electrodes showed the diffusion-controlled contribution is greater than the capacitive-controlled contribution for MS-300 electrode. Also capacitive-controlled contribution is proportional to the scan rates. An asymmetric device was assembled using activated carbon and MoS2 as negative and positive electrodes respectively, which exhibited an areal capacitance of 277.3 mFcm−2 and energy density of 0.15 mWhcm−2 at 5.33 mWcm−2 power density measured at 3 mAcm−2 current density. Furthermore, 90.1% cyclability and excellent coulombic efficiency measured up to 3000 cycles were observed for an asymmetric device. These results depict the potential candidature of MoS2 and MoS2//AC devices as an emerging energy storing devices.
An electrode with multi electron surfaces facilitates more redox sites during charge storage reaction in the case of transition metal oxides used in supercapacitor application. Molybdenum (Mo) oxide ...and manganese (Mn) oxide have high theoretical capacitance; this study focused on depositing Mo–Mn together in a single mixed metal oxide. Here, Mo–Mn hydroxide was deposited on Ni-foam by a single-step hydrothermal method. The X-ray photoelectron spectroscopy confirms the presence of Mo and Mn in 4+ and 3+ oxidation states, respectively. The different size of Mo–Mn hydroxide microstructures was observed with varying deposition time. The porous cubes-like microstructure exhibited high areal capacitance of 88.6 mF cm−2 with energy density of 3.08 μWh·cm−2 at 125 μW cm−2 power density within a kinetic potential. This microcubes-like structures and activated carbon were used as positive and negative electrodes, respectively, to fabricate an asymmetric supercapacitor (ASS) device. The ASS device showed capacitance retention of 87% (∼5,000 cycles) and excellent Coulombic efficiency (96%) with energy density of 5.6 μWh·cm−2 at 1.12 mW cm−2 power density at 1.8 V potential.
Konkan is a coastal strip parallel to Sahyadri hill ranges, which rises from mean sea level to 300 meter height having annual rainfall range from 2300 mm to 4100 mm(Anonymous, 2013).Climate change is ...acting as a trigger for changing rainfall pattern and temperature which can have significant impacts on hydrological cycle and crop calendar of the region (Abrol etal., 2004)....the presents study was undertaken to analyse the trends in annual and seasonal rainfall and temperaturein the Konkan region.Maximum temperature during summer season exhibited significant decreasing trend at Suksale, Bhatsanagar and Pali....the maximum temperature has decreasing trend in the north part of the Konkan region during all seasons, whereas it has increasing trend in middle part of the region during all seasons and during summer season in the south part of the region.
Lead free x(Ba
0.7
Ca
0.3
)TiO
3
–(1 − x)Ba(Zr
0.2
Ti
0.8
)O
3
where x = 0.4 and 0.5 ceramic solid solution system were prepared by hydroxide co-precipitation method. These solid solution ceramics ...were sintered using the microwave sintering technique. The structural, dielectric and ferroelectric properties were analyzed by X-ray diffraction, scanning electron microscope, dielectric impedance spectroscopy and polarization with applied electric field measurements. From the X-ray analysis it is seen that there is formation of pure perovskite phase with coexistence of tetragonal and rhombohedral structures. Dielectric constant and loss tangent were studied as a function of frequency and temperature. Temperature dependant dielectric properties are measured in the frequency range between 1 kHz and 1 MHz. The well known diffuse phase transition (DPT) behavior of the ferroelectric material exists near the room temperature which is also confirmed from the frequency dependent dielectric spectra. The gamma (γ) values were 1.32 and 1.61 for x = 0.4 and 0.5 respectively. It confirms the ferroelectric nature of materials which is in between the normal ferroelectrics and relaxor ferroelectrics. Saturation polarization values were observed 1.28 and 1.95 µC/cm
2
for x = 0.4 and 0.5 respectively with the promising coercive field.
Introduction: It has been observed that there is inadequate retention of microbiology and its inappropriate application to clinical science among medical graduates. To address this problem and ...facilitate student's learning, we need to adopt active, student centric teaching learning methods. Case-based learning (CBL) is one such method .The present study was planned to introduce Case Based Learning (CBL) in Microbiology and assess its advantages in understanding the topic in comparison to traditional didactic lecture and to observe perception regarding CBL among faculty and students.
Material and Methods: 96 MBBS second Prof Students were enrolled in the study after obtaining informed consent and Institutional Ethics Committee approval. Theory lectures and CBL sessions were taken on the selected topics. At the end of both, the lectures and CBL sessions, a post test (MCQ) was conducted. A repeat test was taken after 4 weeks from the first post-test (MCQ) for each topic to see the retention of topic. Feedback of students and faculty were taken on a pre-validated questionnaire and analysed using a 5 point Likert scale.
Results: A total of 96/100 (96%) students participated in the study. The CBL scores were significantly higher than DL session scores (P < 0.001). The difference in scores was significant even after four weeks of session (P < 0.001). Student reported satisfaction in being taught by CBL method in 5-point Likert scale feedback form (mean score >4) and recommended it for future batches.
Conclusions: The study concludes that Case Based Learning is an active method of student centric learning resulting in better understanding, critical analysis, communication and retention of subject topics among students. The faculty also approved of the method in spite of being demanding and lack of adequate resources opining that the method is of special use in discussing clinically relevant topics.
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