Experimental study on performance,combustion and emission characteristics of a four-stroke diesel engine using blended fuel

In day today's applications, it is obligatory to devise the usage of diesel in an economic and environmentally benign way. The present work was aimed at studying the performance, emission and combustion characteristics of a four-stroke diesel engine by adding n-pentane at different proportions such as 2%, 4%, 6%, 8% and 10% by volume with diesel. The performance, combustion and emission characteristics obtained from the experiment revealed that the addition of n-pentane augments the brake thermal efficiency of the engine. At full load, the brake thermal efficiency increased by 3.17% for an addition of 6% n-pentane, 4.31% for an addition of 8% n-pentane and 6.36% for an addition of 10% n-pentane. From the emission test, it was concluded that at full load, the NO_x emission decreased by 8.67% for an addition of 6% n-pentane, 17.43% for an addition of 8% n-pentane and 18.09% for an addition of 10% n-pentane.     

Design and optimization of concurrent tolerance in mechanical assemblies using bat algorithm

Concurrent designing of tolerance has become a vital concern in product and process development due to the relationship between quality, functionality and product cost. It is one of the well explored areas in combinatorial optimization. In this paper, a recently developed optimization algorithm, called Bat algorithm (BA), is used for optimizing the tolerance based on concurrent objectives to minimize the manufacturing cost, present worth of expected quality loss and quality loss. The mechanical assemblies such as Bevel gear assembly (A), Gear box assembly (B) and Suction union assembly (C) are considered to demonstrate the proposed algorithm. It is found that the BA has produced better results than other methods in initial generations for concurrent tolerance problems.     

1,3,4-Oxadiazole epoxy resin-based liquid crystalline thermosets and their cure kinetics

Liquid crystalline thermosets were synthesized based on a difunctional liquid–crystal (LC) epoxy resin monomer, namely 2,5-bis(4-glycidyloxyphenyl)-1,3,4-oxadiazole with various tetrafunctional crosslinkers such as diaminodiphenyl methane, diaminodiphenyl sulfone, and diaminodiphenyl ether. The epoxy monomer was characterized by infrared and nuclear magnetic resonance spectroscopy. Cure kinetics of a stoichiometric mixture of epoxy monomer and diaminodiphenyl methane was investigated by differential scanning calorimetry (DSC) for specimens cured under various cure conditions. The nematic LC texture for the cured specimen was identified by polarized microscopy and confirmed by X-ray diffractometry. Phase diagram of cure time versus transition temperature was constructed based on the DSC data for epoxy/DDM system. The diagram displayed the changes of melting transition, isotropic transition, and glass transition temperatures as curing proceeds.     

Investigation of SR method grown 0 0 1 directed KDP single crystal and its characterization by high-resolution X-ray diffractometry (HRXRD), laser damage threshold, dielectric, thermal analysis, optical and hardness studies

0 0 1 directed potassium dihydrogen orthophosphate (KDP) single crystal was grown by Sankaranarayanan–Ramasamy (SR) method. The 0 0 1 oriented seed crystals were mounted at the bottom of the platform and the size of the crystals were 10 mm diameter, 110 mm height. Two different growths were tried, in one the crystal diameter was the ampoule's inner diameter and in the other the crystal thickness was less than the ampoule diameter. In the first case only the top four pyramidal faces were existing whereas in the second case the top four pyramidal faces and four prismatic faces were existing through out the growth. The crystals were grown using same stoichiometric solution. The results of the two growths are discussed in this paper. The grown crystals were characterized by high-resolution X-ray diffractometry (HRXRD), laser damage threshold, dielectric, thermal analysis, UV–vis spectroscopy and microhardness studies. The HRXRD analysis indicates that the crystalline perfection is excellent without having any very low angle internal structural grain boundaries. Laser damage threshold value has been determined using Nd:glass laser operating at 1054 nm. The damage threshold for the KDP crystal is greater than 4.55 GW cm⁻². The dielectric constant was higher and the dielectric loss was less in SR method grown crystal as against conventional method grown crystal. In thermal analysis, the starting of decomposition nature is similar in SR method grown KDP crystal and conventional method grown crystal. The SR method grown KDP has higher transmittance and higher hardness value compared to conventional method grown crystals.     

Use of encapsulated bacteriophages to enhance farm to fork food safety

Bacteriophages have been successfully applied to control the growth of pathogens in foods and to reduce the colonization and shedding of pathogens by food animals. They are set to play a dominant role in food safety in the future. However, many food-processing operations and the microenvironments in food animals' guts inactivate phages and reduce their infectivity. Encapsulation technologies have been used successfully to protect phages against extreme environments, and have been shown to preserve their activity and enable their release in targeted environments. A number of encapsulation technologies have shown potential for use with bacteriophages. This review discusses the current state of knowledge about the use of encapsulation technologies with bacteriophages to control pathogens in foods and food animals.     

A 2D sub-threshold current model for single halo triple material surrounding gate (SHTMSG) MOSFETs

In the proposed work analytical modeling of single halo triple material surrounding gate (SH-TMSG) MOSFET is developed. The threshold voltage and subthreshold current has been derived using parabolic approximation method and the simulation results are analyzed. The threshold voltage roll off is reduced and it denotes the deterioration of short channel effects. The results of the analytical model are delineated and compared with MEDICI simulation results and it is well corroborated.     

Ground state structures and properties of Si<Subscript>3</Subscript>H<Subscript>n</Subscript> (n = 1–6) clusters

The ground state structures and properties of Si ₃H_n (1 ≤n ≤ 6) clusters have been calculated using Car-Parrinello molecular dynamics with simulated annealing and steepest descent optimization methods. We have studied cohesive energy per particle and first excited electronic level gap of the clusters as a function of hydrogenation. Hydrogenation is done till all dangling bonds of silicon are saturated. Our results show that over coordination of hydrogen is favoured in Si3Hn clusters and the geometry of Si₃ cluster does not change due to hydrogenation. Cohesive energy per particle and first excited electronic level gap study of the clusters show that Si₃H₆ cluster is most stable and Si₃H₃ cluster is most unstable among the clusters considered here.     

A New Hybrid Cuckoo Search Algorithm for Biclustering of Microarray Gene-Expression Data

ABSTRACT

Biclustering in gene-expression data is a subset of the genes demonstrating consistent patterns over a subset of the conditions. Recently, the most of research in biclustering involving statistical and graph-theoretic approaches by adding or deleting rows and/or columns in the data matrix based on some constraints. This is an exhaustive search of the space, and hence the solutions may not be feasible. The proposed work finds the significant biclusters in large expression data using shuffled cuckoo search with Nelder–Mead (SCS-NM). The diversification and intensification of the search space are obtained through shuffling and simplex NM, respectively. The proposed work is tested on four benchmark datasets, and the results are compared with the swarm intelligence techniques and the various biclustering algorithms. The results show that there is significant improvement in the fitness value of proposed work SCS-NM. In addition, the work determines the biological relevance of the biclusters with Gene Ontology in terms of function, process and component.     

Microstructural and Magnetic Features of SrFe<Subscript>12</Subscript><Emphasis Type="Italic">O</Emphasis><Subscript>19</Subscript> Materials Synthesized from Different Fuels by Sol-Gel Auto-Combustion Method

The nanocrystalline SrFe₁₂ O ₁₉ materials were prepared by a sol-gel auto-combustion method using different fuels such as citric acid, dextrose, aniline, and hexamine. The combustion product obtained from all the fuels except from that of aniline show a single phase of SrFe₁₂ O ₁₉ materials upon annealing at 1000 ^°C/2 h. The combustion product obtained from aniline as fuel shows SrFe₁₂ O ₁₉ as the main phase with α-Fe₂ O ₃ as impurity. No notable change in lattice parameters is observed due to variation in fuels for SrFe₁₂ O ₁₉ materials. With a little change in the NIR relative reflectance (72–85 %) on fuels, the different SrFe₁₂ O ₁₉ materials display high NIR reflectance in the wavelength range, 1500–2500 nm. The photoluminescence emission spectra of SrFe₁₂ O ₁₉ materials reveal a broad emission peak at ～350 nm which is reminiscent to the Ba-based hexaferrite, BaFe₁₂ O ₁₉. The FESEM images expose quite dissimilar morphology for the various fuels used in the synthesis of SrFe₁₂ O ₁₉ materials. Hysteresis loops for all the nanocrystalline SrFe₁₂ O ₁₉ materials observed under the applied field of ±1.5 T at room temperature exhibit hard ferromagnetic property. The SrFe₁₂ O ₁₉ materials produced from glycine and aniline as fuels exhibit highest and lowest M _s values of 61.3 and 50.5 emu/g, respectively.     

Effect of linker structure on surface density of aptamer monolayers and their corresponding protein binding efficiency

A systematic study is reported on the effect of linker size and its chemical composition toward ligand binding to a surface-immobilized aptamer, measured using surface plasmon resonance. The results, using thrombin as the model system, showed that as the number of thymidine (T) units in the linker increases from 0 to 20 in four separate increments (T(0), T(5), T(10), T(20)), the surface density of the aptamer decreased linearly from approximately 25 to 12 pmol x cm(-2). The decrease in aptamer surface density occurred due to the increased size of the linker molecules. In addition, thrombin binding capacity was shown to increase as the linker length increased from 0 to 5 thymidine nucleotides and then decreased as the number of thymidine residues increased to 20 due to a balance between two different effects. The initial increase was due to increased access of thrombin to the aptamer as the aptamer was moved away from the surface. For linkers greater in length than T(5), the overall decrease in binding capacity was primarily due to a decrease in the surface density. Incorporation of a hexa(ethylene glycol) moiety into the linker did not affect the surface density but increased the amount of thrombin bound. In addition, the attachment of the linker at the 3'- versus the 5'-end of the aptamer resulted in increased aptamer surface density. However, monolayers formed with equal surface densities showed similar amounts of thrombin binding irrespective of the point of attachment.