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51.
Shyam Ramkrishna Garud Belagola Shivakumar Priyanka Navin Kumar Rastogi Maya Prakash 《臭氧:科学与工程》2018,40(3):198-208
Thermal processing is the most widely adopted technology for preservation of juices; however, it is associated with significant changes in nutritional quality and flavor. Combination of nonthermal hurdles (ozone 1.2 g/h, 10 min, and lactic acid 0.5%) reduced total bacterial count of sugarcane juice by 4.3 log and controlled enzymatic activity to a moderate level (reduction of 60% and 72% activity of polyphenol oxidase and peroxidase, respectively). Combined treatment was comparable to thermal treatment in maintaining microbial and sensory quality of sugarcane juice during 1-month storage under refrigerated conditions; however, additional hurdles may be required for extended storage. 相似文献
52.
Solution‐Processed High‐Performance Tetrathienothiophene‐Based Small Molecular Blends for Ambipolar Charge Transport
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Sureshraju Vegiraju Chih‐Yu Lin Pragya Priyanka Deng‐Yi Huang Xian‐Lun Luo Hsiang‐Chi Tsai Shao‐Huan Hong Chia‐Jung Yeh Wei‐Chieh Lien Chien‐Lung Wang Shih‐Huang Tung Cheng‐Liang Liu Ming‐Chou Chen Antonio Facchetti 《Advanced functional materials》2018,28(28)
Four soluble dialkylated tetrathienoacene ( TTAR) ‐based small molecular semiconductors featuring the combination of a TTAR central core, π‐conjugated spacers comprising bithiophene ( bT ) or thiophene ( T ), and with/without cyanoacrylate ( CA ) end‐capping moieties are synthesized and characterized. The molecule DbT‐TTAR exhibits a promising hole mobility up to 0.36 cm2 V?1 s?1 due to the enhanced crystallinity of the microribbon‐like films. Binary blends of the p‐type DbT‐TTAR and the n‐type dicyanomethylene substituted dithienothiophene‐quinoid ( DTTQ‐11 ) are investigated in terms of film morphology, microstructure, and organic field‐effect transistor (OFET) performance. The data indicate that as the DbT‐TTAR content in the blend film increases, the charge transport characteristics vary from unipolar (electron‐only) to ambipolar and then back to unipolar (hole‐only). With a 1:1 weight ratio of DbT‐TTAR DTTQ‐11 in the blend, well‐defined pathways for both charge carriers are achieved and resulted in ambipolar transport with high hole and electron mobilities of 0.83 and 0.37 cm2 V?1 s?1, respectively. This study provides a viable way for tuning microstructure and charge carrier transport in small molecules and their blends to achieve high‐performance solution‐processable OFETs. 相似文献
53.
Dawid Stawski Priyanka Sahariah Martha Hjálmarsdóttir Dorota Wojciechowska Michał Puchalski Már Másson 《纺织学会志》2017,108(6):1041-1049
The paper presents a method of depositing N,N,N-trimethyl chitosan (TMC) layers onto polypropylene and polylactide nonwovens. A two-step modification procedure is applied: first, grafting the nonwovens with acrylic acid and next layer-by-layer deposition. Turbidimetric measurements confirm the creation of polycomplexes between grafted poly(acrylic acid) and deposited TMC. The created material structure is evaluated using gravimetric analysis, reflectance Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy measurements and pH-metric titration. The modified material exhibits good antibacterial properties against Gram-positive bacteria Staphylococcus aureus. 相似文献
54.
Sonalee Das Priyanka Pandey Smita Mohanty Sanjay Kumar Nayak 《Polymer-Plastics Technology and Engineering》2017,56(14):1556-1585
Castor oil has gained momentous attention as a valuable bio-based monomer and a potential alternative to the current petrobased polyol for synthesizing polyurethane due to the presence of inherent hydroxyl group. In spite of its huge potentiality very little has been reviewed regarding the development of polyurethane from castor oil. This review thus highlights the recent trends and development in the field of polyurethane and its nanocomposite based on castor oil including its biodegradability and weatherability studies. Further, this review also provides an insight regarding the utilization of castor oil based polyurethane and its nanocomposite for coating application. 相似文献
55.
Dileep Singh Chauhan Rashmi Agrawal Priyanka Rastogi 《Numerical Heat Transfer, Part A: Applications》2013,63(2):136-157
This study considers magnetohydrodynamic flow and heat transfer outside a hollow stretching cylinder immersed in a fluid saturated porous medium of sparse distribution of particles with high permeability. Partial slip boundary conditions for the velocity and temperature fields are assumed at the stretching surface of the cylinder. Using similarity transformations, the nonlinear partial differential equations governing the flow and heat transfer are converted into nonlinear ordinary differential equations which are then solved by the homotopy analysis method. The effects of the pertinent parameters on the velocity and temperature profiles are investigated and discussed graphically. 相似文献
56.
Priyanka Malik R.S. Gupta Rishu Chaujar Mridula Gupta 《Microelectronics Reliability》2012,52(1):151-158
In this paper, the RF performance for Gate Material Engineered-Trapezoidal Recessed Channel (GME-TRC) MOSFET has been investigated and the results so obtained are compared with Trapezoidal Recessed Channel (TRC) MOSFET and Rectangle Recessed Channel (RRC) MOSFET, using device simulators; ATLAS and DEVEDIT. Further, the impact of technology parameter variations in terms of negative junction depth (NJD), gate metal workfunction difference, substrate doping (NA) and corner angle, on GME-TRC MOSFET has also been evaluated. The simulation study shows the increase in transconductance and decrease in parasitic capacitance, which further contributes towards a significant improvement in cut-off frequency (ft) in GME-TRC MOSFET as compared to conventional TRC and RRC MOSFETs. Moreover, the significant enhancement in maximum available power gain (Gma), maximum transducer power gain (GMT), maximum unilateral power gain (MUG), maximum frequency of oscillation (fMAX) and stern stability factor (K) have also been observed for GME-TRC MOSFET due to reduced short channel effects (SCEs) and enhanced current driving capabilities. Further, the experimental data for grooved gate MOSFET has also been verified with the simulated data and a good agreement between their results is obtained. 相似文献
57.
Jood P Mehta RJ Zhang Y Peleckis G Wang X Siegel RW Borca-Tasciuc T Dou SX Ramanath G 《Nano letters》2011,11(10):4337-4342
ZnO is a promising high figure-of-merit (ZT) thermoelectric material for power harvesting from heat due to its high melting point, high electrical conductivity σ, and Seebeck coefficient α, but its practical use is limited by a high lattice thermal conductivity κ(L). Here, we report Al-containing ZnO nanocomposites with up to a factor of 20 lower κ(L) than non-nanostructured ZnO, while retaining bulklike α and σ. We show that enhanced phonon scattering promoted by Al-induced grain refinement and ZnAl(2)O(4) nanoprecipitates presages ultralow κ ~ 2 Wm( -1) K(-1) at 1000 K. The high α~ -300 μV K(-1) and high σ ~ 1-10(4) Ω(-1 )m(-1) result from an offsetting of the nanostructuring-induced mobility decrease by high, and nondegenerate, carrier concentrations obtained via excitation from shallow Al donor states. The resultant ZT ~ 0.44 at 1000 K is 50% higher than that for the best non-nanostructured counterpart material at the same temperature and holds promise for engineering advanced oxide-based high-ZT thermoelectrics for applications. 相似文献
58.
Priyanka Choudhary Smita Mohanty Sanjay K. Nayak Lakshmi Unnikrishnan 《应用聚合物科学杂志》2011,121(6):3223-3237
Poly(L lactide) (PLA) was blended with polypropylene (PP) at various ratios (PLA:PP = 90 : 10, 80 : 20, 70 : 30, and 50 : 50) with a melt‐blending technique in an attempt to improve the melt processability of PLA. Maleic anhydride (MAH)‐grafted PP and glycidyl methacrylate were used as the reactive compatibilizers to induce miscibility in the blend. The PLA/PP blend at a blend ratio of 90 : 10, exhibited optimum mechanical performance. Differential scanning calorimetry and thermogravimetric analysis studies showed that the PLA/PP/MAH‐g‐PP blend had the maximum thermal stability with the support of the heat deflection temperature values. Furthermore, dynamic mechanical analysis findings revealed an increase in the glass‐transition temperature and storage modulus with the addition of MAH‐g‐PP compatibilizer. The interaction between the compatibilizers and constituent polymers was confirmed from Fourier transform infrared spectra, and scanning electron microscopy of impact‐fractured samples showed that the soft PP phase was dispersed within the PLA matrix, and a decrease in the domain size of the dispersed phase was observed with the incorporation of MAH‐g‐PP, which acted as a compatibilizer to improve the compatibility between PLA and PP. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
59.
The temperature dependence of open-circuit voltage (Voc) and curve factor (CF) of a silicon solar cell has been investigated in temperature range 295-320 K. The rate of decrease of Voc with temperature (T) is controlled by the values of the band gap energy (Eg), shunt resistance (Rsh) and their rates of change with T. We have found that Rsh decreases nearly linearly with T and its affect on dVoc/dT is significant for cells having smaller Rsh values. Series resistance also changes nearly linearly with voltage. CF depends not only on the value of Rs and other parameters but also on the rate of change of Rs with voltage. The rate of decrease of Rs with voltage and T are important to estimate the value of CF and its decrease with temperature accurately. 相似文献
60.
Priyanka Reddy Tim Plozza Vilnis Ezernieks Dario Stefanelli Alessio Scalisi Ian Goodwin Simone Rochfort 《International journal of molecular sciences》2022,23(11)
The triggers of biennial bearing are thought to coincide with embryonic development in apple and occurs within the first 70 days after full bloom (DAFB). Strong evidence suggests hormonal signals are perceived by vegetative apple spur buds to induce flowering. The hormonal response is typically referred to as the floral induction (FI) phase in bud meristem development. To determine the metabolic pathways activated in FI, young trees of the biennial bearing cultivar ‘Nicoter’ and the less susceptible cultivar ‘Rosy Glow’ were forced into an alternate cropping cycle over five years and an inverse relationship of crop load and return bloom was established. Buds were collected over a four-week duration within 70 DAFB from trees that had maintained a four-year biennial bearing cycle. Metabolomics profiling was undertaken to determine the differentially expressed pathways and key signalling molecules associated with biennial bearing. Marked metabolic differences were observed in trees with high and low crop load treatments. Significant effects were detected in members of the phenylpropanoid pathway comprising hydroxycinnamates, salicylates, salicylic acid biosynthetic pathway intermediates and flavanols. This study identifies plant hormones associated with FI in apples using functional metabolomics analysis. 相似文献