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Recent advances in the photovoltaic applications of coordination polymers and metal organic frameworks
No full textCoordination polymers and metal organic frameworks (CPs/MOFs) have attracted a great deal of attention in a variety of scientific fields due to their unique and intriguing structural properties. Photovoltaic applications of these porous polymers belong to a relatively new area of research. The current status of research on this subject amply highlights the usefulness of CPs/MOFs in improving the properties of next-generation photovoltaic devices (e.g., dye-sensitized solar cells). This review article was written to cover the recent advancements that have been achieved in this rapidly expanding area of research. It also compares and contrasts the energy conversion efficiencies in photovoltaic applications using different MOFs and other systems
Design and Validation of an Open-Source, Partial Task Trainer for Endonasal Neuro-Endoscopic Skills Development: Indian Experience
No full textBACKGROUND:
Box trainers are ideal simulators, given they are inexpensive, accessible, and use appropriate fidelity.
OBJECTIVE:
The development and validation of an open-source, partial task simulator that teaches the fundamental skills necessary for endonasal skull-base neuro-endoscopic surgery.
METHODS:
We defined the Neuro-Endo-Trainer (NET) SkullBase-Task-GraspPickPlace with an activity area by analyzing the computed tomography scans of 15 adult patients with sellar suprasellar parasellar tumors. Four groups of participants (Group E, n = 4: expert neuroendoscopists; Group N, n =19: novice neurosurgeons; Group R, n = 11: neurosurgery residents with multiple iterations; and Group T, n = 27: neurosurgery residents with single iteration) performed grasp, pick, and place tasks using NET and were graded on task completion time and skills assessment scale score.
RESULTS:
Group E had lower task completion times and greater skills assessment scale scores than both Group N and R (P ≤ 0.03, 0.001). The performance of Groups N and R was found to be equivalent; in self-assessing neuro-endoscopic skill, the participants in these groups were found to have equally low pretraining scores (4/10) with significant improvement shown after NET simulation (6, 7 respectively). Angled scopes resulted in decreased scores with tilted plates compared with straight plates (30° P ≤ 0.04, 45° P ≤ 0.001). With tilted plates, decreased scores were observed when we compared the 0° with 45° endoscope (right, P ≤ 0.008; left, P ≤ 0.002).
CONCLUSIONS:
The NET, a face and construct valid open-source partial task neuroendoscopic trainer, was designed. Presimulation novice neurosurgeons and neurosurgical residents were described as having insufficient skills and preparation to practice neuro-endoscopy. Plate tilt and endoscope angle were shown to be important factors in participant performance. The NET was found to be a useful partial-task trainer for skill building in neuro-endoscop
Nanofibers synthesis of ND:PANI composite by liquid/liquid interfacial polymerization and study on the effect of NDs on growth mechanism of nanofibers
No full textPolyaniline (PANI) has exclusive doping/dedoping chemistry and it can be produced in various oxidation states with different electrical and structural properties. The nanocomposite of PANI with nanodiamonds shows unique properties due to molecular level interaction between nanodiamond (ND) and PANI structures. We synthesized ND:PANI composite first time by interfacial polymerization under controlled conditions. The composites were characterized with the help of UV–vis, FTIR, Raman spectroscopies and field effect scanning electron microscope. Herein, we are reporting synthesis of fibrous and conducting composites. In addition, varying concentrations of NDs improves primary growth, lowers the diameter of fibers and cause augmentation in the polymerization. The detailed mechanism of PANI and ND:PANI synthesis is validated with the time dependent study of the aqueous phase. The whole mechanism is alienated into six zones on the basis of reaction progression
Window based Multiple Model Adaptive Estimation for Navigational Framework
No full textKalman filter based algorithms aim at providing accurate estimate of the state parameters which is indirectly governed by the accuracy of the sensor measurement and noise parameters fed to the system model. Multiple Model Adaptive Estimation (MMAE) is one of the adaptive techniques which tries to reduce the dependency of Kalman filter on the noise parameters fed to the system. The main goal of this work is to improve state estimation by incorporating window size as one of the unknown parameters in MMAE framework, referred to as Window based MMAE (WMMAE). The proposed scheme intertwines the concepts of Innovation Adaptive Estimation (IAE) and MMAE in one structure and the state estimation for each model is implemented by IAE. Simulation results prove the efficacy of WMMAE scheme as compared to MMAE and its other variants
Large-mode-area single-polarization single-mode photonic crystal fiber: design and analysis
No full textA rectangular core photonic crystal fiber structure has been presented and analyzed for single-polarization single-mode operation. Single-polarization is obtained with asymmetric design and by introducing different loss fo
Technological improvements in electrostatic spraying and its impact to agriculture during the last decade and future research perspectives – A review
No full textAn important aspect of research in electrostatic force field applications to liquid sprays involves pesticide spraying, painting, printing, thin film coating, medical, Nano biotechnology, transportation etc. The desired attributes of such spraying are uniform deposition onto both directly exposed (adaxial) and obscured (abaxial) crop surfaces which minimizes the off-target losses of active ingredients to soil, water, atmosphere and provides economic pest control. This paper presents an overview of electrostatic spraying technologies in the field of agriculture and perishable fruits/food products emphasizing the key role of advanced electrostatic spraying instrumentation and chronicles the scientific innovations in the parlance of providing cost effective and reliable commercial systems along with an insight on the needs of future research perspectives and directives
Design and analysis of single-mode tellurite photonic crystal fibers for stimulated Brillouin scattering based slow-light generation
No full textWe theoretically examine two designs of single-mode (i) Er-doped tellurite and (ii) undoped tellurite photonic crystal fiber (PCF) for generation of slow light with tunable features based on stimulated Brillouin scattering. We obtained (i) Brillouin gain up to 91 dB and time delay of ∼145 ns∼145 ns at maximum allowable pump power of ∼775 mW∼775 mW in a 2 m Er-doped tellurite PCF and (ii) Brillouin gain up to ∼88 dB∼88 dB and time delay of ∼154 ns∼154 ns at maximum allowable pump power ∼21 mW∼21 mW in a 100 m undoped tellurite photonic crystal fiber. Simulated results clearly indicate that the doped tellurite PCF with Er enhances the maximum allowable pump power and comparable time delay can be obtained even with reduced photonic crystal fiber length. We believe that the carried out examination and simulation have potential impact on design and development of slow-light-based photonic devices applicable in telecommunication systems, enhancement of optical forces, and quantum computing
Highly sensitive and selective detection of trinitrotoluene using cysteine-capped gold nanoparticles
No full textTrinitrotoluene (TNT), being an electron deficient species, can easily bind with electron rich amine groups and form a specific charge transfer Jackson–Meisenheimer (JM) complex. In the present study, we report the formation of a JM complex using cysteine capped gold nanoparticles in the presence of TNT. Sodium citrate is used as reducing agent for the synthesis of gold nanoparticles in an aqueous dispersion. The as synthesized gold nanoparticles are capped with L-cysteine (Au@Cys), an amino acid possessing an additional thiol functional group besides the alpha-amine. The interaction of gold nanoparticles with cysteine in the presence of TNT (AuCys@TNT) is investigated using UV-vis spectroscopy, Raman spectroscopy, FTIR spectroscopy and TEM. A possible model for cysteine binding to gold nanoparticles and the formation of the JM complex, leading to the ultra-trace detection of TNT up to 1 ppb with good reproducibility (n = 3), is also suggested
Enhanced Photocatalytic Performance of Chromium Doped Zinc Oxide Nanoparticles
No full textPure and chromium doped ZnO nanoparticles were successfully synthesized by eco-friendly and cost effective sol–gel technique. Structural, morphological and optical properties of pure and Cr doped ZnO nanoparticles were analyzed by X-ray diffraction, transmission electron microscope, and UV–vis spectroscopic techniques, respectively. The crystallite size of pure ZnO nanoparticles were observed to decrease from 29 to 24 nm as dopant concentration was increased to 3 %. Band gap of pure ZnO nanoparticles were also observed to decrease from 3.5 to 3.37 eV with increase in dopant concentration. The photo-catalytic degradation of methyl blue dye under UV irradiation was examined for synthesized samples. The chromium doped zinc oxide nanoparticles were found to give enhanced photo degradation efficiency (75.5 %) than the pure zinc oxide nanoparticles (51.2 %)
High Voltage Generation for Charging of Liquid Sprays in Air-Assisted Electrostatic Nozzle System
No full textElectrostatic induction charging has proven itself as one of the best methods adopted in agricultural pesticides spraying. Pesticide droplets get charged while passing through a charging electrode which is connected to a high voltage along with the grounded liquid jet. Negatively charged droplets follow the electric lines of forces and get attracted towards the target which is at ground potential. In this paper, a compact size DC to DC converter is designed and developed to generate high voltage. The circuit consists of two sections, a DC to AC converter and an AC to DC converter, which can also be termed as an inverter and Cockcroft Walton multiplier. The converter utilized a 9.0 volt DC rechargeable battery to give a high voltage output. The converter has been used for spray charging in air-assisted electrostatic nozzle system placed inside the nozzle holder. The results were in good agreement with the theoretical concepts and practices. The designed power supply system showed the output stability at higher frequency range which has optimum ripple and voltage drop when applied with load