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Project-based learning (PBL) provides an effective practical application to the learners. Further, PBL develops problem-solving, critical thinking, etc., in the learner. This paper describes a type of project offered to the students at the collegiate level to enhance the students' ability to work in a team, manage a project, and present their results. These projects use acoustic waves in the ultrasound frequency range that can be used as a powerful nondestructive tool for the characterization of the materials. In situ measurement of the ultrasonic longitudinal velocity and evaluation of the elastic constants carried out on the materials in solid pellet form over a wide range of temperatures at a fundamental frequency of 5 MHz enables the study of various phase transitions, such as metal to insulator, ferromagnetic to paramagnetic, and even structural phase transitions that occur in the materials. Here, the investigation is elaborated on using ultrasonic waves on some materials in pellet form and the results obtained are presented.

In this work describes the cobalt-beta hydroxyl benzoate (Co-bhb), Cobalt based complex has been synthesized by solvothermal method and verified for the application detection and removal of environmentally hazardous molecule like methylene blue. The Co-bhb sample were characterized by various techniques like FTIR, PXRD, MS-Mass analysis, NMR, and SEM, EDX, ES-TEM,XPS, PL and BET surface area measurement. The Co-bhb/cp electrode was prepared and electrochemical performance was carried out to explore the electrical activity of the complex for dye sensor application. The Cyclic voltammetry studies were made in 0.05M K4Fe (CN)6 solution and electrochemical sensing experiments were performed in 0.05M H2SO4. An excellent response resulted of the Co-bhb/cpe for sensing the dye at very low concentrations. In addition the photocatalytic activity of degradation of Methylene blue has been performed. The results have showed that the Co-bhb is a promising candidate for electrochemical and catalytic properties.

The present work describes the pyrolysis of zinc acetylacetonate carried out at 700 °C in a sealed quartz tube under inert ambient conditions. The resulting carbonaceous powder material was characterised by XRD and Raman analysis, electron microscopy, X-ray photoelectron spectroscopy, and elemental analysis. These analyses reveal that nanometre-sized hexagonal wurtzite ZnO is embedded in graphitic carbon and graphite oxide, forming a nanocomposite, designated ZnO/C/GO. A pellet of ZnO/C/GO was tested as a conductometric gas sensor for detecting hydrogen sulphide (H2S). The composite shows a rapid and significant response of 220% at 150 °C to 5 ppm of H2S gas, with response and recovery time of 20 s and 30 s, respectively. The detection limit is found to be 250 ppb of H2S, with good selectivity over SO2, NO2, CH4 and ammonia. The novel way to synthesise a carbonaceous nanocomposite, its sensitivity to H2S at a relatively low temperature (implying low power consumption), and its selectivity, promise a cost-effective carbonaceous oxide composite-based sensor for H2S at ppm concentrations.

Internet of things in recent times has been the driving power to the globe for its affordable and easily executable solutions. It is in this line a well-organized system has been developed for urban farming. Urban farming simply refers to producing food in urban spaces. City farming has gained a greater significance in the recent days, as accessing an appreciable amount of food for sustainability has been a grave concern for many families across the world. Also, with massive urbanization and population growth, the fertile land is declining day to day. Hence urban farming is likely to be the most feasible solution to avoid food scarcity. However, it has to be done in a way that it is more beneficial. The system propounded here aims at monitoring and maintaining the essential growth parameters like light, temperature, etc. prevailing to a plant whereby assuring a maximum yield.

Indium acetylacetonate, a β-diketonate complex, was pyrolyzed at 700 °C in inert ambient in a sealed quartz tube, to yield a powder composite of nanocrystalline In2O3 and elemental carbon (In2O3/C), as deduced from characterization by powder X-ray diffraction and Raman spectroscopy. Scanning electron microscopy shows that the metal oxide is embedded in micrometer-sized spherical structures, composed largely of carbon. The spherical entities are likely formed when the metal complex melts, decomposes, and vaporizes during pyrolysis, with the vapour condensing into spherical “droplets” as the sealed tube cools gradually to room temperature. The In2O3/C composite was tested (in pellet form) as a gas sensor, specifically the conductometric sensing of H2S. At 5 ppm of H2S, the composite shows a high response of 225% at 250 °C, with the response and recovery being swift (~ 5 s and ~ 15 s, respectively). At 250 °C, the detection limit is found to be of 500 ppb of H2S, with selectivity over NH3, NO2, CH4, and SO2 being considerable. The In2O3/C sensor also displays good cyclability. When carbon in the composite is removed by annealing it in air (550 °C, 60 min), the resulting In2O3 powder (in pellet form) shows a much poorer response to H2S at 250 °C (25% to 5 ppm), illustrating that the elemental carbon in In2O3/C enhances sensitivity to H2S. The advantages of a simple fabrication process and low power consumption make the carbonaceous composite sensor potentially useful.

A simple, highly sensitive stability indicating reverse phase high-performance liquid chromatographic (RP-HPLC) method was developed and validated for the determination of sumatriptan succinate in bulk and tablet dosage form. The analysis was performed on reverse phase C18 ODS Inertsil (250×4.6mm, 5µm) column, with a mobile phase containing buffer: aetonitrile: methanol (80:10:10 v/v/v), pH was adjusted to 2.5 with orthophosphoric acid (OPA) at 221nm, by an isocratic elution mode with 1ml/min flow rate using photo diode array (PDA) detector at ambient temperature. The injection volume and retention time was found 20μl and 4.4minutes respectively. The method produced linear responses in the concentration range of 5-150 µg/ml, with a correlation coefficient of 0.999. The limit of detection (LOD) and limit of quantification (LOQ) values for HPLC method were found to be 1.967 and 5.961 μg/ml respectively. The recovery of the method was 98% of the labelled value. This method was validated for accuracy, precision, linearity and robustness. Sumatriptan subjected to different ICH prescribed stress conditions of acid, alkali, peroxide, reduction, thermal, photolytic and humidity degradation. This method successfully applied to stability indicating method and also found to be routine quantitative analysis of sumatriptan by easily available materials with low cost.

We report on the demonstration of (InxGa1-x)2O3 (InGaO)-based UV photodetectors realized using a low temperature (∼200 °C) microwave irradiation-assisted deposition technique. By irradiating a solution of the substituted acetylacetonate (acac) complex, namely In0.6Ga0.4(acac)3, employed as the “single-source precursor”, InGaO film was deposited on sapphire substrate, and found to be poly(nano)crystalline, with root mean square (r.m.s). roughness of 8.9 nm. However, the indium content of the film (0.26 mol fraction) was considerably less than in the metal complex (0.6 mol fraction). The optical band gap of the film was found to be 4.5 eV from Tauc’s plot, indicative of a low indium mole fraction. This was confirmed using X-ray photoelectron spectroscopy measurements, from which the indium mole fraction was found to be 0.26. Further, the nature of band gap was determined and defect analysis was carried out using, respectively, Tauc’s plot and cathodoluminescence (CL) measurements. A planar, interdigitated metal-semiconductor-metal (MSM) photodetector fabricated with the InGaO film exhibited a high responsivity of 16.9 A/W at a bias of 20 V, corresponding to a band edge at ∼ 276 nm, with a high photo-to-dark current ratio of ∼105.

The formation of a complete solid solution between acetylacetonate (acac) complexes of chromium and gallium, (Cr1-x,Ga-x)(acac)(3) for 0.1

In an effort to develop new MOCVD precursors, mixed-ligand metal-organic complexes, bis (acetylacetonato-k2O,O′) (2,2′-bipyridine-k2N,N′) magnesium(II), and bis (acetylacetonato-k2O,O′) (1,10-phenanthroline-k2N,N′) magnesium(II) were synthesized. Spectroscopic characterization and crystal structures confirmed them to be monomeric and stable complexes. Crystal structure analysis suggests in each of the magnesium(II) complexes, the metal center has a distorted octahedral coordination geometry. Thermo-gravimetric analysis (TGA/DTA) suggests that these complexes are volatile and thermally stable. The thermal characteristics of newly designed complexes make them attractive precursors for MOCVD applications.

Background: Diabetic foot ulcer is a very common condition encountered in surgical practise. Wound management pose a good challenge for a treating surgeon due to its physical, mental and social implications. The devitalised necrotic tissue present in ulcer does not favour the wound healing as it increases the chance of infection and delays appearance of granulation tissue. Hence debriding of devitalised tissue plays a key role in wound care. In present study ,we used papain urea based preparation in dressings which is a autolytic agent. This study was conducted to evaluate the effectiveness of use of papain urea based preparations compared with regular conventional dressing in diabetic foot ulcer management.Methods: This was a prospective study conducted in K. R. Hospital, Mysore, Karnataka, India. 60 eligible subjects with diabetic foot ulcers were selected and subjects were randomly allocated into two groups Group A and Group B with 30 subjects in each group. Subjects in Group A underwent dressing with papain urea based preparation and in Group B underwent regular conventional dressing. Results were assessed with respect to percentage decrease in necrotic tissue, incidence of infection, appearance of granulation and hospital stay.Results: Among Group A subjects percentage reduction of necrotic tissue was more, granulation appeared early and the hospital stay was less compared to Group B subjects which were statistically significant. However, there was no significant difference with respect to incidence of infection in both groups.Conclusions: Papain urea based preparation is effective in diabetic foot ulcer care.

This paper presents a real time front-end admission control scheme for ATM networks. A call management scheme which uses the burstiness associated with traffic sources in a heterogeneous ATM environment to effect dynamic assignment of bandwidth is presented. In the proposed scheme, call acceptance is based on an on-line evaluation of the upper bound on cell loss probability which is derived from the estimated distribution of the number of calls arriving. Using this scheme, the negotiated quality of service will be assured when there is no estimation error. The control mechanism is effective when the number of calls is large, and tolerates loose bandwidth enforcement and loose policing control. The proposed approach is very effective in the connection oriented transport of ATM networks where the decision to admit new traffic is based on the a priori knowledge of the state of the route taken by the traffic.

In the title compound, [Zn(C(5)H(7)O(2))(2)(C(5)H(5)N)], the metal atom has square-pyramidal coordination geometry with the basal plane defined by the four O atoms of the chelating acetyl-acetonate ligands and with the axial position occupied by the pyridine N atom. The crystal packing is characterized by a C-H⋯O hydrogen-bonded ribbon structure approximately parallel to [10[Formula: see text]].

We present a real time front-end admission control scheme for ATM networks which dynamically shapes the traffic. The call management scheme uses the burstiness associated with traffic sources in a heterogeneous ATM environment to effect dynamic assignment of bandwidth. Call acceptance is based on an on-line evaluation of the upper bound on cell loss probability. The negotiated grade of service will be assured using this control scheme when there is no estimation error. The control mechanism is effective when the number of calls is large, and tolerates loose bandwidth enforcement and loose policing control. The proposed approach is very effective in the connection oriented transport of ATM networks where the decision to admit new traffic is based on the a priori knowledge of the state of the route taken by the traffic. >