Advance electrochemical oxidation of fipronil contaminated wastewater by graphite anodes and sorbent nano hydroxyapatite

Degradation of C₁₂H₄Cl₂F₆N₄OS phenylpyrazole insecticide (Fipronil) by advance electrochemical oxidation in aqueous water solution was studied. The process efficiency was figured based on the COD, chloride, and fluoride reduction from fipronil. Further, we tried to highlight the importance of nano-hydroxyapatite (n-Hap) as a cost-effective nano sorbent for removal of fluoride from fipronil. From the advance electrochemical oxidation experiment, it was found that the COD removal was 79%, chloride 52%, and fluoride 80%. The intermediate of fipronil compounds was examined by GC-MS. The final results conclude that advance electrochemical oxidation process was effective for removal of fipronil synthetic wastewater.     

Effect of storage period on provitamin-A carotenoids retention in biofortified maize hybrids

Vitamin A-rich maize hybrids provide sustainable solutions to malnutrition. However, significant loss of carotenoids during storage reduces its efficacy. Grains of nine sub-tropically adapted crtRB1-based biofortified hybrids along with six normal hybrids were stored under conventional storage for five months. PVAC (β-carotene and β-cryptoxanthin) among crtRB1-based hybrids degraded from initial level of 18.77 to 3.24 µg g⁻¹, while NPVAC (lutein and zeaxanthin) reduced to 10.79 µg g⁻¹ from 19.00 µg g⁻¹ during storage. Among PVAC, β-cryptoxanthin (21.8%) possessed more stability than β-carotene (16.4%). For NPVAC, lutein (61.2%) showed the highest retention than zeaxanthin (50.4%). Majority of the PVAC loss occurred within first three months of storage. Retention for PVAC among crtRB1-based hybrids varied from 14% to 23% indicating the role of favourable genetic factors. APQH1, APQH7 and APH2 were the promising hybrids with higher retention (>20%) of PVAC. This is the first report on identification of provitamin A-rich crtRB1-based biofortified maize hybrids with higher retention during sub-tropical storage.     

Dual chemosensing properties of new ferrocene-based receptors towards fluoride and copper(II) ions

The new ferrocene based receptors N-[4-ferrocenyl-2-methyl-4-oxobut-1-enyl]-N′-phenylthiourea (1), N-[4-ferrocenyl-2-methyl-4-oxobut-1-enyl]-N′-[4-nitrophenyl]thiourea (2) were synthesized and characterized. Fluorescence titrations of receptors 1 and 2 with various transition metal ions showed selective response to Cu²⁺ ions and the emission intensities quenched significantly. Electrochemical titrations with anions revealed that receptors 1 and 2 sensed the F⁻ anion in high selectivity with a cathodic shift of 100 mV.     

Preparation,characterization, and functional analysis of zinc oxide nanoparticle-coated cotton fabric for antibacterial efficacy

Nanotechnology is an emerging interdisciplinary technology and nanostructures capable of enhancing the physical properties of conventional textiles in areas such as antimicrobial properties, water repellence, soil resistance, antistatic, anti-infrared and flame-retardant properties, dye ability, color fastness, and strength of textile materials. The studies were carried out in order to fine tune the preparation of zinc oxide nanoparticles (NPs) for special applications. Soluble starch (stabilizing agent), zinc nitrate and sodium hydroxide (precursors) were used for the preparation of zinc oxide NPs by wet chemical method. The synthesized NPs were coated on cotton fabric (plain weave), and the antibacterial property of the treated fabric was analyzed. Fourier transform infrared spectroscopic analysis, scanning electron microscopy, and physical and chemical characterization were employed to determine the phase and morphology of the final nanoparticle-coated fabric. The results indicated that 2% zinc oxide nanoparticle (200 nm) -coated fabric have high antibacterial efficiency (99.9% against Staphylococcus aureus and 80% against Escherichia coli) and upon washing the coated fabric (five hand washes), the antibacterial activity was found to be 98% against S. aureus and 75% against Escherichia coli.     

Non-invasive evaluation of carotid artery wall thickness using improved dynamic programming technique

An improved dynamic programming (DP) segmentation technique for detecting the intima-media layer of the far wall of the common carotid artery (CCA) of longitudinal and transversal ultrasound (US) images using optimal search technique is presented here. The algorithm is developed considering the normalization and smoothing for estimating the intima media thickness (IMT) of the normal and abnormal subjects. The segmentation features of different subjects obtained using the proposed technique have been compared with the manual measurements. The results show that an inter-observer error and a coefficient of variation are found as ±0.035 mm and 3.55%, respectively. The magnitudes of the IMT values have been used to explore the rate of prediction of blockage existing in the cerebrovascular and cardiovascular pathologies, and also hypertension and atherosclerosis.     

Attic radiant barrier systems: A sensitivity analysis of performance parameters

During the past seven years, the Florida Solar Energy Center (FSEC) has conducted extensive experimental research on radiant barrier systems (RBS). This paper presents recent research on the development of mathematical attic models and results from a sensitivity analysis of RBS performance parameters. Two levels of modelling capability have been developed. A very simplified model based on ASHRAE procedures is used to study the sensitivity of RBS performance parameters, and a very detailed finite-element model is used to study highly complex phenomena, including moisture adsorption and desorption in attics. The speed of the simple model allows a large range of attic parameters to be studied quickly, and the finite-element model provides a detailed understanding of combined heat and moisture transport in attics. This paper concentrates on the sensitivity analysis of attic RBS performance parameters using the simplified model. The development of the model is described, and results of the analyses are presented and discussed. Results from the finite-element model are also presented and compared with measurements from a test attic to illustrate the effects of moisture adsorption and desorption in common attics. The simplified steady-state model shows excellent agreement with measured steady-state data when thermal stratification of the attic air is modelled. Results of the sensitivity analysis using this model show that the radiant barrier surface emittance and the attic ventilation inlet air temperature are the most sensitive performance parameters for attic radiant barrier systems. The detailed, finite-element model shows that moisture sorption phenomena can have significant effects in attics. The daily temperature extremes in attics are significant, and they induce a moisture flux at the surfaces of the materials bounding the air zone(s). If this moisture flux is not accounted for in detail (i.e. with fully coupled heat and moisture transport equations) inaccurate surface temperature predictions are likely to occur.     

Profile modification��a design approach for increasing the tooth strength in spur gear

This work applies modular design concepts to designating beverage-container injection molds. This study aims to develop a method of controlling costs and time in relation to mold development, and also to improve product design. This investigation comprises two parts: functionality coding, and establishing a standard operation procedure, specifically designed for beverage-container injection mold design and manufacturing. First, the injection mold is divided into several modules, each with a specific function. Each module is further divided into several structural units possessing sub-function or sub-sub-function. Next, dimensions and specifications of each unit are standardized and a compatible interface is constructed linking relevant units. This work employs a cup-shaped beverage container to experimentally assess the performance of the modular design approach. The experimental results indicate that the modular design approach to manufacturing injection molds shortens development time by 36% and reduces costs by 19??23% compared with the conventional approach. Meanwhile, the information on modularity helps designers in diverse products design. Additionally, the functionality code helps effectively manage and maintain products and molds.     

Performance Analysis of Multiband OFDM System Over Ultra Wide Band Channels Using Kalman Filter

In this paper a modified version of Saleh-Valenzuela (S-V) channel model has been proposed for Ultra Wide Band (UWB) Orthogonal Frequency Division Multiplexing (OFDM) system and the performance has been estimated. In the proposed model, Poisson process has been modified for ray arrival rate and found that the proposed model is optimum for modeling ray arrival rate as compared to S-V model. Also Nakagami fading distribution has been considered in UWB channel model which suits for time varying multipath radio environment. The performance of the proposed channel model has been statistically analyzed over multiband OFDM by considering frequency domain channel estimation technique. The estimated coefficients have been tracked using Kalman filter technique and found that it gives more accurate prediction of channel coefficients as compared with Least Squares and Minimum Mean Square Estimation channel estimation techniques.