Effective thermal conductivity of potato during frying: Measurement and modeling

Abstract

The effective thermal conductivities of potato were measured at various stages of the frying process. Samples were taken at 30 s intervals during frying, and two different methods (line heat source and modified Fitch method) were used to measure the effective thermal conductivity. An iterative Kopelman model was used for the prediction of thermal properties. The effective thermal conductivity decreased as frying time increased. The variation of experimental measurements by both methods and modeling were within 10% over most of the range studied. The probe method yielded values that were not significantly different than the modified Fitch method. Lower standard deviations were obtained with the modified Fitch method.     

Single-crystal neutron diffraction study of ferroelectric Ba0·92Ca0·08TiO3

Crystal structure of BaTiO₃ doped with 8% Ca²⁺ is refined using single-crystal neutron diffraction data and it is shown that the doped Ca²⁺ ion substitutes only at the Ba sites. The refined cell (P4 mm) parameters area=b=3·982(3) Å,c=4·003(3) Å with a finalR value of 0·02 (onF). Existence of multiple domains in the crystal is ruled out based on refinement with multidomain model.     

Rationalized method to enhance the chromium uptake in tanning process: role of Gallic acid

In the present study, a greener approach to tanning process based on Gallic acid (GA: Trihydroxybenzoic acid) assisted chrome tanning has been attempted. The exhaustion, the thermal stability, mechanical strength and organoleptic properties of tanned leather as well as the evaluation of eco-friendly characteristics were investigated. The microshrinkage, differential scanning calorimetric and thermo mechanical analyses show the shrinkage temperature, denaturation temperature and % elongation, respectively, of GA-chrome-tanned leather are more than that of chrome alone. Chrome exhaustion greater than 93 % has been achieved. This high exhaust aid offers fullness and softness to leather compared to chrome alone. The environmental impact assessment reveals that the developed high exhaust chrome tanning process is beneficial as significant reduction in total solids content (TSC) such as dissolved solids and suspended solids in the effluent is achieved when compared to tanning with chrome alone. The GA could bring about the enhancement of chromium(III) uptake, significant reduction in TSC resulting in improved environmental, economic and social positive impact.     

Simulation and optimization of the ohmic processing of highly viscous food product in chambers with sidewise parallel electrodes

Three dimensional numerical simulations of ohmic heating (OH) of highly viscous chicken chow mein sauce in typical and modified pilot scale ohmic heating chambers with sidewise parallel electrodes arrangement were undertaken. The fully coupled momentum, electrostatic and energy transfer partial differential equations were solved using commercial finite element modeling (FEM) software. The residence time (RT) of sauce in the OH treatment chambers was studied by solving the convection and diffusion equation for a tracer species injected in the system. The key parameters affecting the process, including electrical conductivity, σ, thermal conductivity, k, specific heat capacitance, C_p, density, ρ and viscosity, η, were measured experimentally. For the model validation, the predicted current delivered by each generator and temperatures in selected locations were compared with those obtained from trials performed under the same conditions. A good agreement was observed between experimental and simulated data with the coefficients of determination R² = 0.987.     

Sun light mediated synthesis of gold nanoparticles as carrier for 6-mercaptopurine: Preparation,characterization and toxicity studies in zebrafish embryo model

The objective of this study is to synthesize green chemistry based gold nanoparticles by sun light irradiation method. The prepared gold nanoparticles (AuNPs) were modified using folic acid and then coupled with 6-mercaptopurine. These modified nanoparticles were used as a tool for targeted drug delivery to treat laryngeal cancer. In the present study, novel bionanocomposites containing nutrient agar coated gold nano particles (N-AuNPs) coupled with 6-mercaptopurine (drug) (N-AuNPs-Mp), folic acid (ligand) (N-AuNPs-Mp-Fa) and rhodamine (dye) (N-AuNPs-Rd), a fluorescent agent, were prepared and characterized by IR, UV, TEM, Particle size analysis and in vitro stability. The toxicity and fluorescence of N-Au was studied using zebrafish embryo model. The in vitro cytotoxicity of free Mp, N-Au-Mp and N-Au-Mp-Fa against HEp-2 cells was compared and found that the amount of Mp required to achieve 50% of growth of inhibition (IC₅₀) was much lower in N-Au-Mp-Fa than in free Mp and N-Au-Mp.     

Hydrogels based on gelatin poly(hydroxyethyl methacrylate) and poly(butyl acrylate) graft copolymer impregnated with fibrin

Gelatin was graft copolymerized with poly(hydroxyethyl methacrylate and butyl acrylate) and subsequently crosslinked with glutaraldehyde. Fibrin of bovine origin was incorporated onto this graft copolymer and characterized for the percentage of grafting. The infrared spectroscopy, mechanical strength, and water absorption capacity of the composite were also studied. This biomaterial can be used as a hemostat in many phases of surgery and as a wound dressing material. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:555–560, 1997     

Three-dimensional coronary MR angiography using zonal echo planar imaging

Using an adapted two-dimensional spatially selective RF excitation scheme, a novel yet practical three-dimensional (3D) zonal echo-planar imaging technique for MR coronary angiography has been developed. The robustness of the technique compared with the two-dimensional (2D) segmented fast low angle shot (FLASH) method was evaluated using the right coronary artery images of 16 asymptomatic volunteers with a 0.5-T mobile scanner. Each 3D acquisition required multiple breath-holds, and real-time navigator echoes were used to ensure consistent breath-holding. Advantages of the technique include an improved signal-to-noise ratio, clearer depiction of tortuous coronary vessels due to decreased partial volume effects, and reduced motion blurring by the use of a short echo-planar readout.     

Flapping flight for biomimetic robotic insects: part II-flight control design

In this paper, we present the design of the flight control algorithms for flapping wing micromechanical flying insects (MFIs). Inspired by the sensory feedback and neuromotor structure of insects, we propose a similar top-down hierarchical architecture to achieve high performance despite the MFIs' limited on-board computational resources. The flight stabilization problem is formulated as high-frequency periodic control of an underactuated system. In particular, we provide a methodology to approximate the time-varying dynamics caused by the aerodynamic forces with a time-invariant model using averaging theory and a biomimetic parametrization of the wing trajectories. This approximation leads to a simpler dynamical model that can be identified using experimental data from the on-board sensors and the voltage inputs to the wing actuators. The overall control law is a periodic proportional output feedback. Simulations, including sensor and actuator models, demonstrate stable flight in hovering mode.     

Effects of full D1 dopamine receptor agonists on firing rates in the globus pallidus and substantia nigra pars compacta in vivo: tests for D1 receptor selectivity and comparisons to the partial agonist SKF 38393

Many studies have used the D1 agonist SKF 38393 to characterize D1 receptor influences on firing rates in basal ganglia nuclei in vivo. However, SKF 38393 is a partial agonist and so may not be ideal for delineating D1 receptor effects. This study characterizes the effects of four full D1 agonists, SKF 82958 (chloro-APB), SKF 81297 (6-chloro-PB), dihydrexidine and A-77636, on the firing rates of midbrain dopamine and globus pallidus neurons. Recordings were done in fully anesthetized or paralyzed, locally anesthetized rats, and drugs were given systemically intravenously. Dihydrexidine, SKF 81297 and A-77636 were free of rate effects on midbrain dopamine neurons (up to 10.2 mg/kg) and also did not antagonize the inhibitory effects of quinpirole. In contrast, SKF 82958 strongly inhibited dopamine cells through activation of D2 autoreceptors (ED50 = 0.70 mg/kg). Of these drugs, SKF 82958 also was the only one to increase pallidal unit firing rates when given alone (at 5.0 but not 1.0 mg/kg); the other compounds appeared to be selective for postsynaptic D1 receptors. The results suggest that SKF 82958 may be more properly classified as a mixed D1/D2 agonist. In addition, all four agonists strongly potentiated the pallidal response to quinpirole, demonstrating a D1 receptor potentiation of D2 receptor effects. The results support the role of D1 receptors in the midbrain and globus pallidus as previously characterized with SKF 38393. The similar actions of partial and full D1 agonists in these systems support evidence for a D1 receptor reserve and possibly an effector system other than adenylate cyclase.     

Learning automata algorithms for pattern classification

This paper considers the problem of learning optimal discriminant functions for pattern classification. The criterion of optimality is minimising the probability of misclassification. No knowledge of the statistics of the pattern classes is assumed and the given classified sample may be noisy. We present a comprehensive review of algorithms based on the model of cooperating systems of learning automata for this problem. Both finite action set automata and continuous action set automata models are considered. All algorithms presented have rigorous convergence proofs. We also present algorithms that converge to global optimum. Simulation results are presented to illustrate the effectiveness of these techniques based on learning automata. This work is supported in part by an Indo-US project under ONR grant number N-00014-J-1324.