Cross-sectional associations between occupational factors and musculoskeletal pain in women teachers, nurses and sonographers

A. Technical measurements of the physical workload. (DOCX 18 kb

Karakterizacija solvatomorfa metotreksata pomoću termoanalitičkih i drugih metoda

Identification and characterization of different forms of methotrexate were carried out by crystallization from different solvents. Five different forms of the drug were obtained. Appearance of a desolvation endotherm in the DSC accompanied by mass loss in TGA for forms I, II, IV and V showed these forms to be acetonitrile solvate hydrate (form I), trihydrate (forms II and IV) and dimethylformamide solvate (form V), respectively. However, the desolvation peak was absent in form III (obtained from methanol) indicating the absence of any solvent of crystallization. This form was found to be partially crystalline by its XRPD pattern. Solution calorimetry was further used to differentiate between the forms as they differ in lattice energy, resulting in different enthalpies of solution. The dissolution and solubility profiles were correlated with the enthalpy of solution and subsequently with crystallinity of all the forms; the least endothermic form (form III) had the highest dissolution rate.U radu je provedena identifikacija i karakterizacija pet različitih formi metotreksata dobivenih kristalizacijom iz različitih otapala. Desolvatacijska izoterma u DSC popraćena gubitkom mase u TGA za forme I, II, IV i V ukazuje da su te forme solvati s acetonitrilom: hidrat (forma I), trihidrat (forma II i IV) i solvat s dimetilformamidom (forma V). Međutim, desolvatacijski pik je odsutan u formi III (dobivenoj iz metanola) što ukazuje na odsutnost otapala u kristalnoj formi. Ta forma je parcijalno kristalna i pokazuje odgovarajući XRPD uzorak. Energija kristalne ćelije je za različite forme različita, što ima za posljedicu različite entalpije otapanja te omogućava primjenu kalorimetrije otopine za diferencijaciju formi. Topljivost je korelirana s entalpijom otopine i kristaliničnosti svih formi. Najmanje endotermna forma (forma III) je najbolje topljiva

Numerical Study of Natural Convection in a Square Cavity Filled with a Porous Medium Saturated with Nanofluid

Steady state natural convection of Al2O3-water nanofluid inside a square cavity filled with a porous medium is investigated numerically. The temperatures of the two side walls of the cavity are maintained at TH and TC, where TC has been considered as the reference condition. The top and the bottom horizontal walls have been considered to be insulated i.e., non-conducting and impermeable to mass transfer. Darcy–Forchheimer model is used to simulate the momentum transfer in the porous medium. The transport equations are solved numerically with finite volume approach using SIMPLER algorithm. The numerical procedure is adopted in the present study yields consistent performance over a wide range of parameters (Rayleigh number, Ra, 104≤ Ra≤ 106, Darcy number, Da, 10-5≤ Da ≤ 10-3, and solid volume fraction, j, 0.0 ≤ j ≤ 0.1). Numerical results are presented in terms of streamlines, isotherms and average Nusselt number. It was found that heat transfer increases with increasing of both Rayleigh number and Darcy number. It is further observed that the heat transfer in the cavity is improved with the increasing of solid volume fraction parameter of nanofluids

Numerical modeling of nanoparticles transport effect in mixed convection of nanoï‌uid with variable properties in a square cavity with inlet and outlet port

In this paper, the flow field, heat transfer and nanoparticles transport in Al2O3-water nanofluid mixed convection in a square enclosure with inlet and outlet port has been studied numerically. The dimensionless transport equations are solved numerically with a finite volume approach using the SIMPLER algorithm. Nanoparticles transport mechanisms such as Brownian diffusion, thermophoresis and Dufour effect that cause non-uniform concentration distribution are intended in nanoparticles transport model. The study has been carried out for the nanoparticles volume fraction in the range 0 ⤠Ïb ⤠0.04, Richardson numbers 0.01 ⤠Rif,0 ⤠1with two Grashof number Grf,0=104 , 105. The results show that in mixed convection by increasing volume fraction of nanoparticles and the Grashof number for each Richardson number, the average Nusselt number increases and the transport model by affecting on nanoparticles concentration influence the amount of flow velocity and heat transfer so that in low temperature difference homogenous model and at high temperature difference the transport model predicts higher average Nusselt number