X-ray structure determinations have been carried out and analyzed for two conformational polymorphs of α-truxillic acid (2). Polymorph I (cell parameters known since 1959) is isolated upon recrystallization of 2 from acetic acid−petroleum ether solution, while polymorph II (fully characterized in 1993) is the product of a one-phase solid-state reaction of tail-irradiated α-cinnamic acid. For polymorph II, two redeterminations of mixed crystals containing solid solutions of α-cinnamic acid and 2 (68.1 and 89.5%, respectively) were performed. Analysis of the structural parameters of the 1993 and present redeterminations of the polymorph II structures, as well as comparison to data from the Cambridge Structural Database, confirm that claims of errors in the 1993 structure determination of polymorph II are unfounded. X-ray quality crystals of the β-polymorph of trans-cinnamic acid (cell parameters known since 1964) have been obtained from Et2O/petroleum ether solutions; the crystal structure is quite similar ...

Polymorphism of Cinnamic and α-Truxillic Acids: New Additions to an Old Story†

This experiment has studied the exploration of tangent hyperbolic nanofluid (THNF) unsteady magneto-hydrodynamic (MHD) flow with Dufour and Soret effects. The governing partial differential equations (PDE) in terms of continuity, temperature, concentration, and momentum are reformed into ordinary differential equation (ODE) form and then explained numerically by employing the explicit finite difference (EFDM) technique using Fortran programming with the help of Compaq Visual Fortran 6.6a. The behavior of the engaged physical constraints (Weissenberg number, chemical reaction parameter, Lewis number, Eckert number, Prandtl number, thermophoresis number, and Brownian parameter) on temperature, velocity, and concentration are deciphered meticulously. The outcomes indicate that adding the Soret number into the THNF generates an increment in the concentration outline. The same incident happens to Dufour’s number and temperature profile. Assessment of the current findings with earlier distributed literature is identified and observed in a good contract. Consequences of distinctive physical factors on dimensionless velocity, temperature, and concentration are particularized through graphs and tables. 

Numerical exploration of MHD unsteady flow of THNF passing through a moving cylinder with Soret and Dufour effects

Hall and ion slip effects and chemical reaction on MHD rotating convective flow past an infinite vertical porous plate with ramped wall and uniform wall temperatures

In this article, the detailed study of unsteady boundary layer flow over a permeable stretching/shrinking sheet problem of a nanofluid is carried out. The appropriate similarity transformations are utilized to transform the governing equations into nonlinear ordinary differential equations with variable coefficients over an infinite domain. The numerical solution of these equations is achieved by using semi-numerical technique viz. Shifted Chebyshev Collocation Method (SCCM). The variations in velocity, temperature, and concentration profiles under the influence of various physical parameters are analysed and outcomes are expressed in terms of tables and graphs. The obtained results are compared with previous finding for validation along with error analysis. For particular range of stretching/shrinking parameters the dual solutions are exhibited. Also, the range increases with increment in mass suction and unsteadiness parameter, which results into enhancement of skin friction coefficient, local Nusselt number and local Sherwood number. From the graphs it is anticipated that, both temperature and nanoparticle fraction profiles decrease with raise in the values of parameters viz. unsteadiness, suction/injection, Lewis number. Reverse nature of these profiles is observed with the enhancement in thermophoresis parameter. Whereas, temperature increases with increase of Brownian motion and reverse behavior is observed for nanoparticle fraction. 

Analysis of unsteady boundary layer flow of nanofluids with heat transfer over a permeable stretching/shrinking sheet via a shifted Chebyshev collocation method

In this study, mixed convective hybrid-nanofluid flow in a partially heated square cavity with two rotating rough cylinders in presence of an external magnetic field is numerically investigated. A pair of rotating rough cylinders is placed at different locations inside the cavity. The cavity is permeated by an external magnetic field at different inclination angles. Maxwell's thermal conductivity model is modified incorporating Brownian motion of hybrid nanoparticles. The conservation equations of the flow and thermal fields are simulated using finite element method. The effects of different influential parameters such as cylinders rotation velocity (0 ≤ ω ≤ 50), Hartmann number (0 ≤ Ha ≤50), hybrid nanoparticle volume fraction (0% ≤ φ ≤ 5%) and magnetic inclination angle (0° ≤ α ≤ 135°) on the flow and thermal fields are explored via streamlines, isotherms and bar charts of average Nusselt number. The simulated results ensure that mixed convective flow is accelerated with cylinders rotation speed but declines with higher magnetic field strength and hybrid-nanoparticle volume fraction. Heat transfer enhancement is recorded up to 261.29% at highest rotating speed of rough cylinders (ω: 0–50, φ = 1%, Ha = 10). Enhancement of heat transfer rate is found decreasing for increasing magnetic field strength. Lowest heat transfer rate is occurred at highest magnetic field impact (Ha = 50) which is 144.62% less than that of heat transfer in absence of magnetic field (Ha = 0). Optimum heat transfer is found for 5% hybrid nanoparticle volume fraction which is 101.2% more compared to base fluid water. The presence of triangular rough components accelerates the fluid flow and heat transfer rate significantly. In addition, 48.89% more heat transfer is obtained for rotating rough cylinders with triangular components compared to smooth cylinders. Moreover, maximum heat transfer is achieved at magnetic inclination angle of 90°. It is also observed that the flow and thermal fields strongly depend on the cylinders arrangements. 

Hybrid-nanofluid mixed convection in square cavity subjected to oriented magnetic field and multiple rotating rough cylinders

The objective of this research is to explore the heat and mass transfer properties of an unsteady MHD natural convective Non-Newtonian, Casson fluid flow through a permeable vertical plate in the existence of Soret, Dufour, and chemical reaction. The aspects of heat and radiation absorptions are also factored in. Applications of the present study would be useful in magnetic material processing and chemical engineering systems. Mathematically, the flow field situation is expressed in terms of partial differential equations. The transformed flow-narrating partial differential equations of momentum as well as energy and species concentration were numerically solved using the finite element technique. Non-dimensional flow parameters were used to extract the numerical outcomes of velocity, temperature, and concentration, and the outcomes are envisioned graphically. The significance of the factors determining, Nusselt number, Sherwood number, and skin friction is also considered. The outcomes reveal that raising the permeability parameter causes the velocity to improve while enhancing the Casson parameter causes the velocity distribution to reduce. 

An Impact On Non-Newtonian Free Convective Mhd Casson Fluid Flow Past A Vertical Porous Plate In The Existence of Soret, Dufour, and Chemical Reaction

(E)-3-(4-Iodophenyl)propenoic acid, C 9 H 7 IO 2 , M r =274.05, monoclinic, P2 1 /n, a=4.118 (2), b=6.274 (4), c=34.672 (2) A, β=90.32 o , V=895.7 (9) A 3 , Z=4, D x =2.03 Mg m -3 , λ(Mo Kα)=0.71069 A, μ=34.90 cm -1 , F(000)=520, T=153 K, R=0.037, wR=0.043 for 1098 reflections. The crystal structure is characterized by O-H...O, C-H...O and I...I interactions and resembles the packing of 4-iodobenzoic acid and 4-chlorocinnamic acid. The Cambridge Structural Database has been used to study the disorder of the carboxyl group in 47 benzoic acids and 25 cinnamic acids

http://journals.iucr.org/c/issues/1993/06/00/gr1002/gr1002.pdf

B. S. Goud

Papers

An Impact On Non-Newtonian Free Convective Mhd Casson Fluid Flow Past A Vertical Porous Plate In The Existence of Soret, Dufour, and Chemical Reaction

Structure of 4-iodo-trans-cinnamic acid and a study of carboxyl group disorder