Synthesis and characterization of epoxidized neem oil: A bio-derived natural processing aid for elastomer

Low cost and environment-friendly bio-oils are gaining market value as a plasticizer for elastomeric compounds. Unsaturated triglycerides of bio-oils can be easily modified in various ways, like epoxidation, esterification, and so on. In the present work, 15 mole percentage of the total double bond content of the neem oil (NO) was epoxidized by acetic acid-hydrogen peroxide system to synthesize epoxidized neem oil (ENO). NO and ENO were characterized by nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy and differential scanning calorimetry. The effect of ENO on the properties of nonpolar styrene butadiene rubber (SBR) and polar nitrile rubber (NBR) was investigated. Tear strength (69.9 N/mm), abrasion resistance index (ARI) (68.2) and hardness (64 shore A) of the SBR/ENO compound were comparable to the compound containing total distillate aromatic extract (TDAE) (values: 70.8 N/mm, 68.0 and 64 shore A respectively). Tensile strength and ARI of conventional NBR/dioctyl phthalate (DOP) compound were 24.9 MPa and 107 respectively, whereas NBR/ENO compound showed improved tensile strength (26.9 MPa), and ARI (138). Tear strength (83.4 N/mm) and hardness (74 shore A) of NBR/ENO were comparable to the tear strength (83.5 N/mm) and hardness (74 shore A) of NBR/DOP compound. Hence, the multifunctional additive property of ENO makes it a cheap and sustainable replacement of TDAE and DOP.     

A hybrid wavelet–APSO–ANN-based protection scheme for six-phase transmission line with real-time validation

Neural Computing and Applications - The ever-increasing load demand motivates the adoption of the six-phase transmission system as a viable alternative to the conventional three-phase...     

Regulatory practices for nuclear power plants in India

Atomic Energy Regulatory Board (AERB) is the national authority to ensure that the use of ionizing radiation and nuclear energy in India does not cause undue risk to the health of workers and members of the public, and the environment. AERB fulfills its mission by stipulating and enforcing rules and regulations concerned with nuclear and radiological safety. This paper describes the regulatory authorization process of AERB as applicable to nuclear power plants (NPPs) during their construction as well as operating phases. The safety review process during construction is presented as case studies. Some current issues related to operating plants are also described. Two typical examples of safety upgradations made in old generation nuclear plants are given.The regulatory process in India is continuously evolving to cater to the new developments. Some of the recent initiatives taken by AERB in that direction are briefly described. Today AERB faces new challenges like simultaneous review of a large number of new projects of diverse designs, a fast growing nuclear power program and functioning of operating plants in a competitive environment. This paper delineates how AERB is gearing up itself to meet these challenges in an effective manner.     

Nickel(II)‐Mediated Regioselective C?H Monoiodination of Arenes and Heteroarenes by using Molecular Iodine

The 8‐aminoquinoline‐directed, nickel(II)‐mediated ortho‐iodination of benzamides using molecular iodine has been developed. The process is highly regioselective and furnishes only monoiodinated products. A broad range of arenes and heteroarenes with diverse functional groups provided monoiodinated products in good to excellent yields.

     

Directing Group‐Assisted Copper(II)‐Catalyzed ortho‐Carbonylation to Benzamide using 2,2′‐Azobisisobutyronitrile (AIBN)

An efficient copper‐catalyzed regioselective C—H bond carbonylation of benzamides has been developed using 2,2′‐azobisisobutyronitrile (AIBN) as traceless cyanating agent. The non‐toxic and readily available AIBN was used for the carbonylative cyclization of benzamides via copper catalysis. The method is also applicable for the regioselective cyanation of furan, benzofuran, thiophene, benzothiophene, and pyrrole carboxamide derivatives.

     

Nonlinear model of pneumatic conveying dryer for economic process control

Abstract

This paper presents a nonlinear dynamic model, suitable for economic process control of pneumatic conveying dryer for drying of food grains. The dynamic model is developed by reshaping the process equations derived for the batch drying, dilute phase, and a negative-pressure conveying system. The dynamic model parameters are identified by numerically solving a nonlinear least squares optimization problem, subject to a set of differential and algebraic equality constraints that describe the system dynamics and bounds in the parameters. A detailed parametric uncertainty and sensitivity analysis are performed providing valuable insight into the influence of critical model parameters on observables, the interplay among various parameter-state-measured disturbances, and quantifying uncertainties in the model. Further, different process economic performance and product quality indicator of uncertain dryer model are studied. The model validation study as performed with the underlying process shows a very good agreement in understanding necessary dynamic characteristics and interplay between the various parameter of interest.     

Studies on Polymerization of Groundnut Oil in an Azeotropic Salt Bath

The groundnut oil was bodied by passing through an azeotropic salt bath consisting of 53% potassium nitrate, 40% sodium nitrite and 7% sodium nitrate. The bodied oil was fractionated with 5 volumes of dry acetone into soluble and insoluble fractions. The fatty acid compositions of the methyl esters of these fractions were found out by GLC. The bodied oil contains acids with variable chain lengths. The oils show no nitration inspite of their contact with nitrate/nitrite salts at a temperature of 320° C. The methyl esters were also fractionated into two fractions using urea and into four fractions, namely, monomer, dimer, polymer and “oxy” products by column chromatographic technique. These fractions were analysed by GLC, IR and NMR. The esters with carbon numbers 11.5 and 13.5 in DEGS and 17.5, 32.7 and 35.5 in SE-30 columns are oxygenated compounds. The dimers contain 2 types of esters, one with carbon number 36.0, which is probably linked through C? C linkage and/or cyclized; the other, which predominates, is linked through ether linkage.     

Effect of branching in hyperbranched alkyd on the performance of alkyd polyurethane coating

Hyperbranched alkyd was synthesized by single‐step approach using trimethylolpropane, mono pentaerythritol as core material, and 2,2‐bis(methylol)propionic acid (DMPA), a combination of dehydrated castor oil fatty acid and coconut oil fatty acid as chain extender. A series of hyperbranched alkyds were prepared at different degree of branching in the alkyd structures by changing the amount of DMPA in the alkyd resin formulation. The resins were characterized by Fourier transform infrared and ¹H‐nuclear magnetic resonance (NMR) spectroscopic technique. These hyperbranched alkyds were converted into polyurethane coating after reaction with hexamethylene diisocyanate trimer at a definite ratio in the presence of dibutyltin dilaurate as a catalyst. The effect of branching and polymeric chain entanglement on the glass transition temperature, T_g of the alkyd polyurethane coating (APUC) was studied by differential scanning calorimetry technique. The performance of such APUC in terms of gloss, gloss retention under accelerated QUV radiation, natural outdoor exposed condition, mechanical, and corrosion resistance properties were enhanced with the increase of polymeric chain entanglement, i.e., compactness or higher order of branching in the alkyd resin structure. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45835.     

Grey wolf optimization-tuned convolutional neural network for transmission line protection with immunity against symmetrical and asymmetrical power swing

The similar current–voltage profile during power swing and fault quite often leads to maloperation of distance relays. As compared to symmetrical power swings, discriminating a swing scenario from a fault becomes more challenging during asymmetrical swings arising due to single-pole tripping. Unlike symmetrical power swings, the presence of zero-sequence and negative-sequence current during asymmetrical swing scenarios hinders the application of classical power swing blocking schemes. In this regard, a convolutional neural network (CNN)-based protection scheme has been proposed in this paper, which, in addition to detecting, classifying, and locating faults, is also able to discriminate between power swing (both symmetrical and asymmetrical) and faults. The discrimination avoids possible maloperation during the non-faulty stressed conditions, thereby overcoming the limitation of the existing protection scheme. With the convolutional neural network, the raw signals are directly fed to the classifier, thus avoiding the computational cost associated with feature extraction in time and frequency domains. With the aim of achieving improved input–output mapping capability of CNN for larger datasets, an evolutionary optimization technique, i.e., grey wolf optimization, has been utilized for determining the optimal values of CNN tuning parameters. The performance of the proposed scheme has been extensively validated for a wide range of fault and power swing conditions in terms of standard indices, i.e., dependability, security, and accuracy. The effectiveness of the proposed scheme has also been evaluated for practical setting by performing real-time simulation on OPAL-RT digital simulator.