Influence of highly dispersible silica filler on the physical properties,tearing energy,and abrasion resistance of tire tread compound

Rubber industry is facing a stiff challenge in the years to come. There are rising price for fossil fuel and shortage of resources. There is more stringent legislation to protect the environment and reduce the emission. Filler plays an important role in imparting useful properties to rubber products. In this article, the effects of new generation filler, on the physical properties, tearing energy, and abrasion resistance were investigated. The new generation filler, highly dispersible silica, has a dibutyl phthalate (DBP) absorption value of more than 180cc 100 g⁻¹, more branched structure and relatively higher amount of small aggregates. Four different loadings of silica (up to 45 phr) were investigated. With increasing filler loading, the tensile strength and modulus at 300% elongation increased and the elongation-at-break decreased. The rebound resilience decreased and tan delta value improved with increasing silica content. The abradability continuously decreased with concomitant increase in the side coefficient force. The fatigue resistance was found to be better at higher silica loading. The silica particles due to its surface structure helps in crack arresting. The abradibility was related to tearing energy, loss modulus, and breaking energy. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47560.     

Temporal response of biochemical and biological sensors with bimodal surface adsorption from a finite sample

Microsystem Technologies - The importance of adsorption-based biochemical/biological sensors in biochemistry and biophysics is paramount. Their temporal response gives information about the...     

Design of high gain,high bandwidth neural amplifier IC considering noise-power trade-off

Microsystem Technologies - Low Noise Neural amplifiers are used for amplifying low amplitude neural spikes in Neural recording systems. The need for low noise is emphasized by the presence of...     

Fuzzy multi attribute group decision making method to achieve consensus under the consideration of degrees of confidence of experts’ opinions

The aim of this paper is to introduce a fuzzy multi attribute group decision making technique considering the degrees of confidence of experts’ opinions. In the process of decision making, each expert provides his/her evaluation over the alternatives depending on a finite set of attributes and constructs an individual fuzzy decision matrix. The proposed technique establishes an iterative process to aggregate the fuzzy information, given by individual expert, into group consensus opinion by using the fuzzy similarity measure. Then, based on group consensus opinion, the proposed approach utilizes the fuzzy similarity measure to find out the most desirable alternative through approximate reasoning. The proposed decision making technique is more flexible due to the fact that it considers the degrees of confidence of experts’ opinions. Finally an example has been shown to highlight the proposed methodology.     

Pareto-based evolutionary computational approach for wireless sensor placement

Wireless sensor networks (WSNs) have become increasingly appealing in recent years for the purpose of data acquisition, surveillance, event monitoring, etc. Optimal positioning of wireless sensor nodes is an important issue for small networks of relatively expensive sensing devices. For such networks, the placement problem requires that multiple objectives be met. These objectives are usually conflicting, e.g. achieving maximum coverage and maximum connectivity while minimizing the network energy cost. A flexible algorithm for sensor placement (FLEX) is presented that uses an evolutionary computational approach to solve this multiobjective sensor placement optimization problem when the number of sensor nodes is not fixed and the maximum number of nodes is not known a priori. FLEX starts with an initial population of simple WSNs and complexifies their topologies over generations. It keeps track of new genes through historical markings, which are used in later generations to assess two networks’ compatibility and also to align genes during crossover. It uses Pareto-dominance to approach Pareto-optimal layouts with respect to the objectives. Speciation is employed to aid the survival of gene innovations and facilitate networks to compete with similar networks. Elitism ensures that the best solutions are carried over to the next generation. The flexibility of the algorithm is illustrated by solving the device/node placement problem for different applications like facility surveillance, coverage with and without obstacles, preferential surveillance, and forming a clustering hierarchy.     

Hydrogenolysis of sugar beet fiber by supported metal catalyst

Sugar beet fiber is an agricultural by-product in the sugar manufacturing and an available biomass source with a rich hemicellulose component. So far, there has been no report on the catalytic conversion of the beet fiber for the synthesis of chemicals. In this work, the hydrogenolysis of the beet fiber was studied by using supported metal catalysts under pressurized hydrogen conditions. Activated carbon supported Ru was found to show the highest catalytic activity to give arabitol as a major product in the hydrogenolysis of hemicellulose part of this material. The reuse ability of the catalyst was also investigated.     

An experimental and numerical study of water jet cleaning process

In this paper, we have experimentally, numerically and theoretically investigated the water jet cleaning process. Very high speed water jets (∼80-200 m/s) are typically used in such cleaning operations. These jets diffuse in the surrounding atmosphere by the process of air entrainment and this contributes to the spreading of the jet and subsequent decay of pressure. Estimation of this pressure decay and subsequent placement of the cleaning object is of paramount importance in manufacturing and material processing industries. Also, the pressure distribution on the cleaning surface needs to be assessed in order to understand and optimize the material removal process. In an industrial setting, an experimental study is performed to formulate the pressure characteristics. It has been shown that the decay of stagnation pressure along the axial direction is linear. It also revealed that no cleaning is possible at radial locations greater than 1.68D from the centerline. Numerical simulations are performed to capture the process of air entrainment in the jet and the subsequent pressure characteristics. The simulation results are found to correctly predict the experimental data. Moreover, a theoretical model for evaluating the optimal and critical stand-off distances has also been derived. Our results indicate that the optimal stand-off distance in cleaning operations is ∼5D and the jet looses its cleaning ability at axial distances greater than ∼26D.     

Green method for determination of phenolic compounds in mung bean (Vigna radiata L.) based on near‐infrared spectroscopy and chemometrics

Mung bean grains exhibit high level of antioxidant activity due the presence of phenolic compounds. Near‐infrared spectroscopy (NIRS), in conjunction with chemometrics, was used to develop a rapid, nondestructive, chemical free and easy‐to‐use method to determine these compounds in sixty genotypes of mung bean. NIRS calibration curve with high‐performance liquid chromatography (HPLC) as reference method was used to determine phenolic compounds (catechin, chlorogenic acid, caffeic acid, p‐coumaric acid, t‐ferulic acid, vitexin, isovitexin, myricetin, quercetin and kaempferol). It was observed that partial least square regression (PLSR) model in the wavelength range of 1600–2500 nm with standard normal variate (SNV) and linear baseline correction (LBC) as preprocessing techniques can measure phenolic compound accurately (R² > 0.987) with root‐mean‐square error less than 1.82%. This study shows that NIRS along with chemometrics is an accurate method to estimate the phenolic compounds rapidly and nondestructively.     

Synthesis of full interpenetrating network membranes of poly(acrylic acid-co-acrylamide) in the matrix of polyvinyl alcohol for dehydration of ethylene glycol by pervaporation

Polyvinyl alcohol (PVOH) has been chemically modified by crosslink copolymerization of acrylic acid (AA) and acrylamide (AM) in aqueous solution of PVOH and finally crosslinking the copolymer with methylene bis acrylamide (MBA) and PVOH with glutaraldehyde to produce a full interpenetrating network (FIPN) membrane. Accordingly, three such fully crosslinked IPNs i.e. FIPN25, FIPN50 and FIPN75 have been synthesized with different mass ratio of PVOH:copolymer i.e. 1:0.25 (FIPN25), 1:0.50 (FIPN50) and 1:0.75 (FIPN75). These full IPN membranes were used for pervaporative dehydration of ethylene glycol (EG). All of these IPN membranes were characterized with various conventional methods like FTIR, mechanical properties, DTA and SEM. The performances of the membranes were evaluated in terms of sorption and pervaporative dehydration of EG. The IPN membranes were found to show preferential sorption and diffusion for water. Flux and water selectivity of these membranes were found to increase with increasing amount of copolymer in PVOH matrix. However, among the three membranes, FIPN75 were found to show the highest flux but lower selectivity for water while FIPN50 membrane showed optimum performance in terms of both flux and selectivity. Diffusion coefficient and plasticization interaction of water and EG through all the IPN membranes were determined using modified solution-diffusion model.