Vapor grown carbon nanofiber based cotton fabrics with negative thermoelectric power

Vapor grown carbon nanofiber (CNF) based ink dispersions were used to dip-coat woven cotton fabrics with different constructional parameters, and their thermoelectric (TE) properties studied at room temperature. Unlike the positive thermoelectric power (TEP) observed in TE textile fabrics produced with similar carbon-based nanostructures, the CNF-based cotton fabrics showed negative TEP, caused by the compensated semimetal character of the CNFs and the highly graphitic nature of their outer layers, which hinders the p-type doping with oxygen groups onto them. A dependence of the electrical conductivity (r) and TEP as a function of the woven cotton fabric was also observed. The cotton fabric with the largest linear density (tex) showed the best performance with negative TEP values around - 8 lV K-1 , a power factor of 1.65 9 10-3 lW m-1 K-2 , and a figure of merit of 1.14 9 10-6 . Moreover, the possibility of a slight e- charge transfer or n-doping from the cellulose onto the most external CNF graphitic shells was also analysed by computer modelling. This study presents n-type carbon-based TE textile fabrics produced easily and without any functionalization processes to prevent the inherent doping with oxygen, which causes the typical p-type character found in most carbon-based TE materialsFEDER funds through COMPETE and by national funds through FCT – Foundation for Science and Technology within the project POCI-01-0145- FEDER-007136. E. M. F. Vieira is grateful for financial support through FCT with CMEMS-UMinho Strategic Project UIDB/ 04436/202

Macroscopic kinetics of hydrate formation of mixed hydrates of hydrogen/tetrahydrofuran for hydrogen storage

10.1016/j.ijhydene.2013.01.123International Journal of Hydrogen Energy38114587-4596IJHE

Hydrogen storage in clathrate hydrates: Current state of the art and future directions

10.1016/j.apenergy.2014.01.063Applied Energy122112-132APEN

Torso kinematics and low back disorder risk as a function of pallet orientation

The objective of this study was to assess the affect of pallet location on torso kinematics during lifting. Participants transferred 11.3 kg boxes to pallets at two orientations and two distances from a constant lift origin. When reorienting the pallet from 180° to 90°, torso twist, lateral and sagittal torso kinematics increased when palletizing to various locations on the pallet when keeping the pallet distance far. Torso flexion increased slightly at the lowest level on the pallet independent of the pallet distance. When keeping the pallet distance close, torso twist kinematics decreased only when palletizing to the highest and closest position of the pallet. When reorienting the pallet from 180° to 90° adjacent to the lift origin, the best strategy to reduce torso kinematics appears to be to eliminate the transferring of loads to the lowest level of the pallet, and keeping the pallet close to the lift origin. © 2004 - IOS Press and the authors. All rights reserved

The effect of pallet distance on torso kinematics and low back disorder risk.

Intervention research for prevention of occupational low back injuries has focused on the effects of reducing extreme torso flexion and the external moment. Little is known about prevention strategies for torso twisting and lateral bending. The objective of this study was to assess the effect of pallet distance with regard to a constant lift origin on the torso kinematics and a measure of low back disorder risk. Fifteen male participants transferred 11.3 kg boxes from a constant origin to six different regions on a pallet. Two pallet distances with regard to the lift origin were investigated. ANOVA indicated that increasing the pallet distance resulted in increases in torso kinematics (velocities and accelerations) as well as a measure of risk of low back disorder. The increases in torso kinematics (e.g. twisting and lateral awkward postures and bending velocities) occurred mostly at the lower height regions on the pallet. It is concluded that increasing the pallet distance with regard to the lifting origin, with the intention to influence the participant to take a step during a palletizing task does not appear to be an effective intervention strategy to reduce the risk of low back disorder associated with torso kinematics

Hydrate phase equilibrium of ternary gas mixtures containing carbon dioxide, hydrogen and propane

10.1016/j.jct.2013.02.003Journal of Chemical Thermodynamics6158-63JCTD

Thermal-based Zinc-Oxide-Coated Smart Fabric for Thermochromic Applications

The present study focuses on developing a thermochromic device with a flexible substrate through the coating of cotton fabric with ZnO (Zinc oxide) by solvothermal synthesis technique. Here, ZnO is used as the thermochromic layer for the fabrication work, and it is suitable for textile and wearable applications as it is non-toxic to human skin. This device is designed and fabricated in order to gain better insight into the role of ZnO in thermochromic applications. Here, 3D nanostructures of ZnO are grown on the surface of cotton fabric using a simple and cost-effective solvothermal synthesis approach. The coated fabrics are investigated to determine their structure, morphology, composition, electrical, optical and emissivity properties using an X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), current-voltage (I-V) characteristics, ultraviolet protection factor (UPF) etc. From the morphology study, uniformly packed ZnO nanorods with growth in the c -axis direction are observed. The ZnO nanostructures are known to have excellent UPF when exposed to solar radiation and showed UPF value of 112.48. It is found that coated fabrics have increased electrical conductivity under optical excitations and also enhanced the reflectance. Moreover, based on the emissivity analysis coated ZnO cotton fabric showed the emissivity of 0.95, which is higher and has greater radiation protection than that of bare cotton fabric. Hence, the developed thermochromic device has potential for use in the future in textile and wearable based thermochromic application

An ergonomic evaluation of manual Cleco plier designs: Effects of rubber grip, spring recoil, and worksurface angle

The present study evaluated two design modifications (rubber grip and torsion spring) to the conventional manual Cleco pliers by electromyography (EMG), hand discomfort, and design satisfaction. This study also surveyed workers' satisfaction with selected design features of the pliers for ergonomic improvement. A two-way (plier design x worksurface angle) within-subject (nested within gender and hand size) design was employed. Eleven workers simulated the plier task in an adjustable workstation for different plier designs and worksurface angles (0 degrees, 60 degrees, and 90 degrees). Lower EMG values were obtained for the pliers with rubber grip and at 60 degrees of worksurface angle. EMG values varied significantly between the participants, but showed low correlations (Spearman's rank correlation = -0.27 similar to-0.58) with their work experience with the pliers. The hand discomfort and design satisfaction evaluations identified that the grip span (max = 14.0 cm) and grip force requirement (peak = 220.5 N) of the current pliers need ergonomic modification. The present study shows the needs of both the ergonomic design of a hand tool and the training of a proper work method to control work-related musculoskeletal disorders at the workplace. (c) 2005 Elsevier Ltd. All rights reserved.X1112sciescopu