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This study attempts to identify factors that significantly encourage the cessation of smoking in the context of Pakistan. The study distributes a modified questionnaire among 421 respondents (current as well as former smokers) in the capital city of Pakistan, Islamabad. The binary regression method was employed to data for analyzing predictors of making quit attempts and successful smoking cessation. The result indicates that respondents having strong intentions to quit, high socioeconomic status, low nicotine dependency, and past quit attempts, and those having no-smoking friends, are more likely to quit cigarette smoking successfully. On the other hand, factors like social pressure to quit smoking, religious information against smoking, intention to quit smoking, and public regulation on smoking are more likely to encourage smokers to make quit attempts. The study calls for community and school-wide smoking cessation campaigns involving officials, peers and parents, religious leaders, and other influential individuals to inform people about the dangers of smoking. In addition, religious leaders should be encouraged to issue rulings against smoking especially during "Friday Prayer." Furthermore, the government should pronounce more strict and comprehensive regulations on smoking by properly monitoring its implementation to encourage cessation of cigarette smoking.
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Abandono do Hábito de Fumar , Fumar , Paquistão , Humanos , Fumar/epidemiologia , Masculino , Inquéritos e Questionários , Feminino , AdultoRESUMO
BACKGROUND: The study aimed to investigate the effect of urea molasses mineral blocks (UMMB) on nutrient digestibility, productive performance and blood biochemical profile of indigenous yaks under various feeding systems. A total of sixteen yaks were randomly divided into four groups (n = 4 animal per group) and offered the, following feeding systems: (A) stall feeding, (B), urea molasses mineral block (UMMB) + stall feeding, (C) yard feeding and (D) UMMB + yard feeding. Trial lasted for 40 days. RESULTS: Results showed that nutrients intake (g) and nutrient digestibility (%) of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE) and crude fiber (CF) were significantly higher (p < 0.05) in stall and yard feeding groups with UMMB licking. Blood zinc, cobalt, hemoglobin (Hb), red blood cell (RBC), glucose and serum glutamate private transaminase (SGPT) significantly (p < 0.05) increased in stall and yard feeding with UMMB licking. Milk yield, Ca and monounsaturated fatty acid except milk composition improved significantly (p < 0.05) in stall and yard feeding groups with UMMB licking. CONCLUSION: It was concluded that feeding of UMMB improved utilization of low-quality roughages and best results were obtained from stall and yard feedings with UMMB licking as compared to other groups.
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Melaço , Ureia , Animais , Bovinos , Minerais , Nutrientes , EritrócitosRESUMO
Grid-based approaches render an efficient framework for data clustering in the presence of incomplete, inexplicit, and uncertain data. This paper proposes an entropy-based grid approach (EGO) for outlier detection in clustered data. The given hard clusters obtained from a hard clustering algorithm, EGO uses entropy on the dataset as a whole or on an individual cluster to detect outliers. EGO works in two steps: explicit outlier detection and implicit outlier detection. Explicit outlier detection is concerned with those data points that are isolated in the grid cells. They are either far from the dense region or maybe a nearby isolated data point and therefore declared as an explicit outlier. Implicit outlier detection is associated with the detection of outliers that are perplexedly deviated from the normal pattern. The determination of such outliers is achieved using entropy change of the dataset or a specific cluster for each deviation. The elbow based on the trade-off between entropy and object geometries optimizes the outlier detection process. Experimental results on CHAMELEON datasets and other similar datasets suggested that the proposed approach(es) detect the outliers more precisely and extend the capability of outliers detection to an additional 4.5% to 8.6%. Moreover, the resultant clusters became more precise and compact when the entropy-based gridding approach is applied on top of hard clustering algorithms. The performance of the proposed algorithms is compared with well-known outlier detection algorithms, including DBSCAN, HDBSCAN, RE3WC, LOF, LoOP, ABOD, CBLOF and HBOS. Finally, a case study for detecting outliers in environmental data has been carried out using the proposed approach and results are generated on our synthetically prepared datasets. The performance shows that the proposed approach may be an industrial-oriented solution to outlier detection in environmental monitoring data.
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Algoritmos , Entropia , Análise por ConglomeradosRESUMO
Conducting polymers integrated with metal oxides create opportunities for hybrid capacitive electrodes. In this work, we report a one-pot oxidative polymerization for the synthesis of integrated conductive polyindole/nickel oxide (PIn/NiO), polyindole/zinc oxide (PIn/ZnO), and polyindole/nickel oxide/zinc oxide (PNZ). The polymers were analyzed thoroughly for their composition and physical as well as chemical properties by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-Vis), and thermogravimetric analysis (TGA). The PIn and its composites were processed into electrodes, and their use in symmetrical supercapacitors in two- and three-electrode setups was evaluated by cyclic voltammetry (CV), galvanostatic discharge (GCD), and electrochemical impedance spectroscopy (EIS). The best electrochemical charge storage capability was found for the ternary PNZ composite. The high performance directly correlates with its uniformly shaped nanofibrous structure and high crystallinity. For instance, the symmetrical supercapacitor fabricated with PNZ hybrid electrodes shows a high specific capacitance of 310.9 F g-1 at 0.5 A g-1 with an energy density of 42.1 Wh kg-1, a power density of 13.2 kW kg-1, and a good cycling stability of 78.5% after 5000 cycles. This report presents new electrode materials for advanced supercapacitor technology based on these results.
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AIMS AND OBJECTIVES: This study sets out to describe benefits from the implementation of electronic observation charting in intensive care units (ICU). This was an extension to the existing hospital wide digital health system. We evaluated error reduction, time-savings and the costs associated with conversion from paper to digital records. The world health emergency of COVID-19 placed extraordinary strain on ICU and staff opinion was evaluated to test how well the electronic system performed. METHODS: A clinically led project group working directly with programmers developed an electronic patient record for intensive care. Data error rates, time to add data and to make calculations were studied before and after the introduction of electronic charts. User feedback was sought pre and post go-live (during the COVID-19 pandemic) and financial implications were calculated by the hospital finance teams. RESULTS: Error rates equating to 219 000/year were avoided by conversion to electronic charts. Time saved was the equivalent of a nursing shift each day. Recurrent cost savings per year were estimated to be £257k. Staff were overwhelmingly positive about electronic charts in ICU, even during a health pandemic and despite redeployment into intensive care where they were using the electronic charts for the first time. DISCUSSION: Electronic ICU charts have been successfully introduced into our institution with benefits in terms of patient safety through error reduction and improved care through release of nursing time. Costs have been reduced. Staff feel supported by the digital system and report it to be helpful even during redeployment and in the unfamiliar environment of intensive care.
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COVID-19 , Pandemias , Humanos , Saúde Global , Cuidados Críticos , Unidades de Terapia IntensivaRESUMO
Eco-friendly inhibitors have attracted considerable interest due to the increasing environmental issues caused by the extensive use of hazardous corrosion inhibitors. In this paper, environmentally friendly PDG-g-PANI/Al2O3 composites were prepared by a low-cost inverse emulsion polymerization for corrosion inhibition of mild steel (MS) and stainless steel (SS). The PDG-g-PANI/Al2O3 composites were characterized by different techniques such as X-ray diffraction (XRD), UV/Vis, and FTIR spectroscopy. XRD measurements show that the PDG-g-PANI/Al2O3 composite is mostly amorphous and scanning electron micrographs (SEM) reveal a uniform distribution of Al2O3 on the surface of the PDG-g-PANI matrix. The composite was applied as a corrosion inhibitor on mild steel (MS) and stainless steel (SS), and its efficiency was investigated by potentiodynamic polarization measurement in a 3.5% NaCl and 1 M H2SO4 solution. Corrosion kinetic parameters obtained from Tafel evaluation show that the PDG-g-PANI/Al2O3 composites protect the surface of MS and SS with inhibition efficiencies of 92.3% and 51.9% in 3.5% NaCl solution, which is notably higher than those obtained with untreated epoxy resin (89.3% and 99.5%). In particular, the mixture of epoxy/PDG-g-PANI/Al2O3 shows the best performance with an inhibition efficiency up to 99.9% on MS and SS. An equivalent good inhibition efficiency was obtained for the composite for 1M H2SO4. Analysis of activation energy, formation enthalpy, and entropy values suggest that the epoxy/PDG-g-PANI/Al2O3 coating is thermodynamically favorable for corrosion protection of MS and exhibits long-lasting stability.
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Computer vision (CV) and human-computer interaction (HCI) are essential in many technological fields. Researchers in CV are particularly interested in real-time object detection techniques, which have a wide range of applications, including inspection systems. In this study, we design and implement real-time object detection and recognition systems using the single-shoot detector (SSD) algorithm and deep learning techniques with pre-trained models. The system can detect static and moving objects in real-time and recognize the object's class. The primary goals of this research were to investigate and develop a real-time object detection system that employs deep learning and neural systems for real-time object detection and recognition. In addition, we evaluated the free available, pre-trained models with the SSD algorithm on various types of datasets to determine which models have high accuracy and speed when detecting an object. Moreover, the system is required to be operational on reasonable equipment. We tried and evaluated several deep learning structures and techniques during the coding procedure and developed and proposed a highly accurate and efficient object detection system. This system utilizes freely available datasets such as MS Common Objects in Context (COCO), PASCAL VOC, and Kitti. We evaluated our system's accuracy using various metrics such as precision and recall. The proposed system achieved a high accuracy of 97% while detecting and recognizing real-time objects.
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The lack of an eco-friendly approach towards application of polyaniline as a coating material has been one of the most challenging tasks. Herein, the synthesis of green Prunus domestica gum grafted polyaniline (PDG-g-PANI) composite is reported by a cost-effective emulsion polymerization for application as an efficient anti-corrosion material for mild steel (MS) and stainless steel (SS) in a strong corroding environment. The composite formation was confirmed by Ultraviolet Visible (UV-Visible) and Fourier Transformed Infrared (FTIR) spectroscopies. X-ray diffraction data revealed the amorphous nature of the PDG-g-PANI. Scanning Electron Microscopic (SEM) images showed a bi-layered structure having a parent porous layer of PANI coated with afibrous layer of PDG. The solubility test confirmed the dissolution of PDG-g-PANI in common organic solvents such as acetone, ethanol, propanol, butanol, chloroform, N-Methyl-2-pyrrolidone, dimethyl sulfoxide, and the mixture of propanol and chloroform. The polarization curve, open circuit potential, electrochemical impendence spectroscopy (EIS), and gravimetric analysis were applied to investigate the corrosion protection behavior of the composite on MS and SS in 3.5% NaCl and 1 M H2SO4 solution. The PDG-g-PANI-coated MS exhibited 96% corrosion inhibition efficiency as compared to 86% and 43% for pristine PANI and PDG in 3.5% NaCl solution while PDG-g-PANI-coated SS showed 98% corrosion inhibition efficiency. Moreover, 99% and 96.6% corrosion protection was observed for PDG-g-PANI-coated MS and SS in 1 M H2SO4 solution. Gravimetric studies revealed that PDG-g-PANI coating can protect MS up to 93% for 14 days in salt solution while 97% corrosion inhibition efficiency was retained for 2 months in open air.
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Due to the environmental and production problems of emulsion, it is important to efficiently separate oil-water emulsion to meet the refinery requirement and clean up oil spills. Synthesis of a universal demulsifier is not an easy task because the physical properties of crude oil vary, which makes its characterization and demulsification procedure difficult. To overcome this problem, hydrophilic and magnetically recoverable poly (methyl methacrylate-acrylic acid)/iron oxide magnetic composite nanoparticles ((P(MMA-AA)/Fe3O4 NPs) were developed as an efficient and economical demulsifier via soap-free emulsion polymerization. To characterize the magnetic composite NPs for their appropriate surface morphology and magnetic domain, TEM, FTIR, VSM, and TGA analyses were carried out. The newly synthesized NPs displayed good hydrophilic properties as they migrated quickly to the aqueous emulsion phase, which was also reassured by their water contact angle of 75°. They exhibit strong magnetic characteristics (20 amu/g) in the oil-water emulsion, makings the hydrophilic wettability capable and attractive to the external magnet. Experimental results revealed that the prepared magnetic composite NPs separated 99% of the water from stable emulsion in 30 min and could be recycled 8 times through magnetic separation. The recycled magnetic composite NPs maintain their hydrophilic wettability and efficiency in separating oil-water emulsion, making them economical and commercially viable. The migration of magnetic composite NPs to the aqueous phase in the stable emulsion with a strong magnetic domain explains the coalescence of emulsified water droplets and their quick separation from the stable emulsions through the external magnet.
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Nanoestruturas , Água , Acrilatos , Emulsões , Compostos Férricos , Fenômenos Magnéticos , Metacrilatos , Metilmetacrilato , Óleos , MolhabilidadeRESUMO
This study aimed to evaluate the impact of dietary addition of jojoba seed oil on productive performance, physicochemical attributes and carcass quality of broiler meat under tropical weather conditions. A total of 384 one-day-old Ross-308 were subdivided into four dietary treatments of jojoba seed oil: 0, 50, 100 and 150 mg/kg of control diet. Each treatment group included twelve replicates with eight birds each. The results showed that dietary supplementation of jojoba seed oil linearly increased (p < 0.01) feed intake, body weight gain and improved (p < 0.01) feed conversion ratio. Interestingly, diets supplemented with jojoba seed oil linearly (p < 0.05) improved the percentage of dressing and reduced abdominal fat percentage compared to the control group. Dietary supplementation of jojoba seed oil showed no effects (p ≥ 0.05) on the weight of internal organs, including liver, heart, gizzard, spleen and pancreas of broiler chickens. Increasing jojoba seed oil levels in the diet decreased (p < 0.001) percentages of cook and drip losses of breast and leg (drumstick and thigh) muscles of broilers. It was concluded that jojoba seed oil used as a feed additive up to 150 mg/kg improves growth performance and meat quality of broiler chickens in tropical weather conditions.
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A polybenzopyrrole@nickel oxide (Pbp@NiO) nanocomposite was synthesized by an oxidative chemical one-pot method and tested as an active material for hybrid electrodes in an electrochemical supercapattery device. The as-prepared composite material exhibits a desirable 3D cross-linked nanostructured morphology and a synergistic effect between the polymer and metal oxide, which improved both physical properties and electrochemical performance. The unprocessed material was characterized by X-ray diffraction, FTIR and UV-Vis spectroscopy, scanning electron microscopy/energy disperse X-ray analysis, and thermogravimetry. The nanocomposite material was deposited without a binder on gold current collectors and investigated for electrochemical behavior and performance in a symmetrical two- and three-electrode cell setup. A high specific capacity of up to 105 C g-1 was obtained for the Pbp@NiO-based electrodes with a gravimetric energy density of 17.5 Wh kg-1, a power density of 1925 W kg-1, and excellent stability over 10,000 cycles.
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Fabrication of composites by developing simple techniques can be an efficient way to modify the desire properties of the materials. This paper presents a detailed study on synthesis of low cost and efficient nitrogen doped reduced graphene oxide nickle-silver (N-rGO-Ni/Ag) and nickel-cobalt (N-rGO-Ni/Co) nanocomposites as electrocatalysts in fuel cell using one-pot blended reflux condensation route. An admirable correlation in the structures and properties of the synthesized nanocomposites was observed. The Oxygen Reduction Reaction (ORR) values for N-rGO-Ni/Ag and N-rGO-Ni/Co calculated from the onset potential, using Linear Sweep Voltammetry (LSV), were found to be 1.096 and 1.146. While the half wave potential were determined to be 1.046 and 1.106, respectively, N-rGO-Ni/Ag and N-rGO-Ni/Co. The Tafel and bi-functional (ORR/OER) values were calculated as 76 and 35 mV/decade and 1.23 and 1.12 V, respectively, for N-rGO-Ni/Ag and N-rGO-Ni/Co. The lower onset and half wave potential, low charge transfer resistance (Rct = 1.20 Ω/cm2) and internal solution resistance (Rs = 8.84 × 10-1 Ω/cm2), lower Tafel values (35 mV), satisfactory LSV measurements and mass activity (24.5 at 1.056 V for ORR and 54.9 at 1.056 for OER) demonstrate the remarkable electrocatalytic activity of N-rGO-Ni/Co for both ORR and OER. The chronamperometric stability for synthesized nanocomposites was found satisfactory up to 10 h.
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Electronically conducting poly (aniline-co-2-hydroxyaniline) (PACHA), a copolymer of aniline and 2-hydroxyaniline (2HA), was electrochemically coated on gold substrate for methanol electrooxidation in alkaline media. The electrochemical behavior of PACHA coated gold electrode towards methanol electrooxidation was investigated via cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) for application in an alkaline fuel cell. Methanol electrooxidation was observed at two different electrode potentials depending on the concentration of the base. At the PACHA coated gold electrode, the methanol oxidation peak was observed at lower overpotential (at 0.19 V) in a solution of high base concentration (1.8 M NaOH), which was 30 mV lower than the peak for the uncoated gold electrode. In addition, the Faradic current Imax obtained on the PACHA coated electrode (20 mA) was two times higher as compared to the Faradic current Imax of the un-modified gold electrode (10 mA). In solution of lower base concentration (0.06 M NaOH), the electrooxidation of methanol became sluggish on both electrodes, as indicated by peak shifting towards positive potential and with reduced faradaic current (at 0.74 V on PACHA coated electrode; Imax 10 mA). The electrooxidation of methanol at both lower and higher electrode potentials was analyzed mechanistically and discussed in light of the literature. EIS results were interpreted using Nyquist and Bode plots. The charge transfer resistance was decreased and pseudo-capacitive behavior changed to conductive behavior when external applied potential was increased from 0.1 V to 0.4 V.
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Polybenzopyrrole (Pbp) is an emerging candidate for electrochemical energy conversion and storage. There is a need to develop synthesis strategies for this class of polymers that can help improve its overall properties and make it as suitable for energy storage applications as other well-studied polymers in this substance class, such as polyaniline and polypyrrole. In this study, by synthesizing Pbp in surfactant-supported acidic medium, we were able to show that the physicochemical and electrochemical properties of Pbp-based electrodes are strongly influenced by the respective polymerization conditions. Through appropriate optimization of various reaction parameters, a significant enhancement of the thermal stability (up to 549.9 °C) and the electrochemical properties could be achieved. A maximum specific capacitance of 166.0 ± 2.0 F g-1 with an excellent cycle stability of 87% after 5000 cycles at a current density of 1 A g-1 was achieved. In addition, a particularly high-power density of 2.75 kW kg-1 was obtained for this polybenzopyrrole, having a gravimetric energy density of 17 Wh kg-1. The results show that polybenzopyrroles are suitable candidates to compete with other conducting polymers as electrode materials for next-generation Faradaic supercapacitors. In addition, the results of the current study can also be easily applied to other systems and used for adaptations or new syntheses of advanced hybrid/composite Pbp-based electrode materials.
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The performance of high-rate supercapacitors requires fine morphological and electrical properties of the electrode. Polyaniline (PANI), as one of the most promising materials for energy storage, shows different behaviour on different substrates. The present study reports on the surface modification of fluorine doped tin oxide (FTO) with the sodium phytate doped PANI without any binder and its utilization as a novel current collector in symmetric supercapacitor devices. The electrochemical behaviour of the sodium phytate doped PANI thin film with and without a binder on fluorine doped tin oxide (FTO) as current collector was investigated by cyclic voltammetry (CV). The electrode without a binder showed higher electrocatalytic efficiency. A symmetrical cell configuration was therefore constructed with the binder-free electrodes. The device showed excellent electrochemical performance with high specific capacities of 550 Fg-1 at 1 Ag-1 and 355 Fg-1 at 40 Ag-1 calculated from galvanostatic discharge curves. The low charge transfer and solution resistances (RCT and RS) of 7.86 Ωcm² and 3.58 × 10-1 Ωcm², respectively, and superior rate capability of 66.9% over a wide current density range of 1 Ag-1 to 40 Ag-1 and excellent cycling stability with 90% of the original capacity over 1000 charge/discharge cycles at 40 Ag-1, indicated it to be an efficient energy storage device. Moreover, the gravimetric energy and power density of the supercapacitor was remarkably high, providing 73.8 Whkg-1 at 500 Wkg-1, respectively. The gravimetric energy density remained stable as the power density increased. It even reached up to 49.4 Whkg-1 at a power density of up to 20 Wkg-1.
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Electroconductive polymeric patches are being developed in the hope to interface with the electroresponsive tissues. For these constructs, conjugated polymers are considered as conductive components for their electroactive nature. Conversely, the clinical applications of these conductive polymeric patches are limited due to their short operational time-a decrease in their electroactivity occurs with the passage of time. This paper reports on the polymerization of aniline on prefabricated chitosan films on microscopic glass slides in the presence of sodium phytate. The strong chelation among sodium phytate, aniline and chitosan led to the formation of electoconductive polymeric patch. We assume that immobilization of sodium phytate in the polymeric patch helps to prevent electric deterioration, extend its electronic stability and reduce sheet resistance. The patch oxidized after three weeks (21 days) of incubation in phosphate buffer (pH 7.4 as physiological medium). This feasible fabrication technique set the foundation to design electronically stable, conjugated polymer-based patches, by providing a robust system of conduction that could be used with electroactive tissues such as cardiac muscles at the interface.
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In the field of advanced energy storage, nanostructured Polyaniline (PANI) based materials hold a special place. Extensive studies have been done on the application of PANI in supercapacitors, however, the structure-property relationship of these materials is still not understood. This paper presents a detailed characterization of the novel sodium phytate doped 3D PANI nanofibers anchored on different types of carbon paper for application in supercapacitors. An excellent relationship between the structures and properties of the synthesized samples was found. Remarkable energy storage characteristics with low values of solution, charge transfer and polarization resistance and a specific capacitance of 1106.9 ± 1.5 F g-1 and 779 ± 2.6 F g-1 at current density 0.5 and 10 Ag-1, respectively, was achieved at optimized conditions. The symmetric supercapacitor assembly showed significant enhancement in both energy density and power density. It delivered an energy density of 95 Wh kg-1 at a power of 846 W kg-1. At a high-power density of 16.9 kW kg-1, the energy density can still be kept at 13 Wh kg-1. Cyclic stability was also checked for 1000 cycles at a current density of 10 Ag-1 having excellent retention, i.e., 96%.
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The major drawbacks of the conventional methods for preparing polyaniline (PANI) are the large consumptions of toxic chemicals and long process durations. This paper presents a remarkably simple and green route for the chemical oxidative synthesis of PANI nanofibers, utilizing sodium phytate as a novel and environmentally friendly plant derived dopant. The process shows a remarkable reduction in the synthesis time and usage of toxic chemicals with good dispersibility and exceedingly high conductivity up to 10 S cm-1 of the resulting PANI at the same time. A detailed characterization of the PANI samples has been made showing excellent relationships between their structure and properties. Particularly, the electrochemical properties of the synthesized PANI as electrode material for supercapacitors were analyzed. The PANI sample, synthesized at pre-optimized conditions, exhibited impressive supercapacitor performance having a high specific capacitance (Csp) (832.5 Fg-1 and 528 Fg-1 at 1 Ag-1 and 40 Ag-1, respectively) as calculated from galvanostatic charge/discharge (GCD) curves. A good rate capability with a capacitance retention of 67.6% of its initial value was observed. The quite low solution resistance (Rs) value of 281.0 × 10-3 Ohm and charge transfer resistance value (Rct) of 7.44 Ohm represents the excellence of the material. Further, a retention of 95.3% in coulombic efficiency after 1000 charge discharge cycles, without showing any significant degradation of the material, was also exhibited.
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Reduced graphene oxide/poly(pyrrol-co-thiophene) (RGO/COP), prepared by facile in-situ oxidative copolymerization, is reported as a new hybrid composite material with improved supercapacitance performance as compared to the respective homopolymers and their composites with RGO. The as-prepared hybrid materials were characterized with ultraviolet-visible (UV-Vis) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analysis. The electrochemical behavior and energy storage properties of the materials were tested by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrostatic impedance spectroscopy (EIS) techniques in 0.5 M H2SO4. The specific capacitance (Csp) for RGO/COP calculated from the CV curve was 467 F/g at a scan rate of 10 mV/s. While the Csp calculated from the GCD was 417 F/g at a current density of 0.81 A/g. The energy density calculated was 86.4 Wh/kg with a power density of 630 W/kg. The hybrid composite exhibits good cyclic stability with 65% capacitance retention after 1000 cycles at a scan rate of 100 mV/s. The present work brings a significance development of RGO/COP composites to the electrode materials for pseudocapacitive application.
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Polymerases are enzymes that synthesize long chains or polymers of nucleic acids including DNA or RNA from nucleotides. They assemble nucleic acids by copying a DNA or RNA template strand using base-pairing interactions. One of the polymerase enzymes, Taq DNA polymerase, originally isolated from Thermus aquaticus (Taq) is a widely used enzyme in molecular biology so far. The thermostable properties of this enzyme have contributed majorly to the specificity, automation, and efficacy of the polymerase chain reaction (PCR), making it a powerful tool for today's molecular biology researches across the globe. The purification of Taq DNA polymerase from the native host results in low yield, more labor and time consumption. Therefore, many studies have been previously conducted to obtain this enzyme using alternative hosts. So far, all the existing methodologies are more laborious, time-consuming and require heavy expense. We used a novel approach to purify the enzyme with relatively high efficiency, yield and minimum time consumption using Escherichia coli (E. coli) as an alternative host. We cloned a 2500 base pair Taq DNA polymerase gene into pGEX-4T-1 vector, containing a GST-tag, downstream of tac promoter and overexpressed it using isopropyl ß-d-1-thiogalactopyranoside (IPTG) as an inducer. The enzyme was efficiently purified using novel chromatography approaches and was used in routine PCR assays in our laboratory. Our findings suggest a novel approach to facilitate the availability of polymerases for molecular and diagnostic studies. In the future, it may be used for the purification of other recombinant peptides or proteins used in structural biology and proteomics-based researches.