Isocyanide-metal binding is governed by σ-donation and π-back-bonding, which affects the energy of the isocyanide stretching mode—a characteristic probe for ligand-metal interactions. While extensive correlations e...
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As global population rises,accompanied by escalating environmental pollution and climate change,numerous countries find themselves grappling with an acute scarcity of natural freshwater resources^([1]).Seawater desali...
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As global population rises,accompanied by escalating environmental pollution and climate change,numerous countries find themselves grappling with an acute scarcity of natural freshwater resources^([1]).Seawater desalination presents a compelling solution to this looming crisis,especially considering the oceans are Earth’s largest water reservoir^([2]).
The dynamic rheological properties of a composite composed of solution-polymerized styrene butadiene rubber (SSBR) filled with starch/silica (SiO_2) compound fillers were studied by means of temperature,frequency and ...
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The dynamic rheological properties of a composite composed of solution-polymerized styrene butadiene rubber (SSBR) filled with starch/silica (SiO_2) compound fillers were studied by means of temperature,frequency and strain sweeps, respectively,and the influence of the starch content in the compound fillers (SCCF) on the rheological behaviors was *** is found from frequency sweeps that a maximum of loss tangent (tanδ) appears at 20 rad/s,which is independent of SCCF.G of the composites decreases w...
In transmission electron microscopy examinations of cast Al matrix-SiC particulate composites, it was noted that a coating of Al4C3 had been formed in contact with some SiC particles. The observed epitaxial orientatio...
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In transmission electron microscopy examinations of cast Al matrix-SiC particulate composites, it was noted that a coating of Al4C3 had been formed in contact with some SiC particles. The observed epitaxial orientation relationships at the SiC/Al4C3 interface and between the carbides and interfacial Al formed by Al4C3 decomposition are described. The lattice matching between SiC, Al4C3, and reprecipitated Al particles may result in strong bonding and thus permit crack propagation across such interfaces, contributing to the detrimental effects on fracture and fatigue associated with the presence of Al4C3 in aluminum-silicon carbide composites,
Pitch-based carbon fiber surfaces were modified using a nickel-catalyzed, dry oxygen etch (NCDO) and a dry oxygen etch (DO), both of which were applied using a continuous process. The treatments differed in that DCDO ...
Pitch-based carbon fiber surfaces were modified using a nickel-catalyzed, dry oxygen etch (NCDO) and a dry oxygen etch (DO), both of which were applied using a continuous process. The treatments differed in that DCDO produced preferential pitting on fiber surfaces at nickel particle sites. Tensile strengths of all etched fibers were slightly lower than values for untreated, or ''as received'' (AR), fibers. Reductions in tensile strength were independent of the type of treatment administered, indicating that most degradation resulted from damage produced by the mechanics of the continuous process, not the etching treatments. Fiber-matrix interfacial shea. strengths (IFSS) of AR and etched fibers were evaluated using the Microbond test At first glance, Microbond test data indicated that NCDO produced large increases in IFSS. However, inconsistencies in the data raised questions regarding the validity and usefulness of the Microbond test when applied to this system. Only after detailed analysis of the data for this series of fibers was it concluded that NCDO did indeed produce an increase in IFSS over AR fibers and DO fibers.
The CO2 permeability of uniaxially drawn high-density polyethylene (HDPE) was investigated and drastic changes were observed as a function of draw ratio. An estimation of variations in both density and fractional free...
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The CO2 permeability of uniaxially drawn high-density polyethylene (HDPE) was investigated and drastic changes were observed as a function of draw ratio. An estimation of variations in both density and fractional free volume of the amorphous component in the drawn polymers was made on the basis of experimental data. The dramatic variations in permeability resulting from drawing were shown to be the consequence of changes of fractional free volume in the amorphous phase of the drawn polymer. Good correlation exists between measured solubility and diffusion coefficients of drawn samples and the estimated fractional free volume;this correlation agrees with the existing free volume theory for diffusion in polymers.
A set of isothermally melt-crystallized polyethylene samples was examined using small-angle x-ray scattering (SAXS). Time and temperature of crystallization were the variable parameters used to create the set of sampl...
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A set of isothermally melt-crystallized polyethylene samples was examined using small-angle x-ray scattering (SAXS). Time and temperature of crystallization were the variable parameters used to create the set of samples. Following background subtraction, desmearing, and application of the Lorentz factor to the raw SAXS data it is possible to see many orders of reflection. This suggests that much higher degrees of order are present in isothermally melt-crystallized samples than had previously been thought possible. A combination of SAXS and DSC data indicates that there is no evidence for isothermal thickening in these samples. This study, coupled with data obtained from PE single crystals, produced information concerning the extrapolation of single-crystal data to fit bulk systems. In addition, the equilibrium melting point T determined is somewhat lower than previously claimed. This study also suggests that the surface energy of the mature crystals is always lower than that of the nucleated state and/or the nucleation factor K σ en increases with decreasing supercooling.
Recently, graphene foam （GF） with a three-dimensional （3D） interconnected network produced by template-directed chemical vapor deposition （CVD） has been used to prepare composite phase-change materials （PCMs） ...
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Recently, graphene foam （GF） with a three-dimensional （3D） interconnected network produced by template-directed chemical vapor deposition （CVD） has been used to prepare composite phase-change materials （PCMs） with enhanced thermal conductivity. However, the pore size of GF is as large as hundreds of micrometers, resulting in a remarkable thermal resistance for heat transfer from the PCM inside the large pores to the GF strut walls. In this study, a novel 3D hierarchical GF （HGF） is obtained by filling the pores of GF with hollow graphene networks. The HGF is then used to prepare a paraffin wax （PW）-based composite PCM. The thermal conductivity of the PW/HGF composite PCM is 87% and 744% higher than that of the PW/GF composite PCM and pure PW, respectively. The PW/HGF composite PCM also exhibits better shape stability than the PW/GF composite PCM, negligible change in the phase-change temperature, a high thermal energy storage density that is 95% of pure PW, good thermal reliability, and chemical stability with cycling for 100 times. More importantly, PW/HGF composite PCM allows light-driven thermal energy storage with a high light-to- thermal energy conversion and storage efficiency, indicating its great potential for applications in solar-energy utilization and storage.
There are many methods currently producing high modulus and high strength films and fibers in industry. This publication examines the results of a hot nip drawing process to produce high modulus PP films at a relative...
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There are many methods currently producing high modulus and high strength films and fibers in industry. This publication examines the results of a hot nip drawing process to produce high modulus PP films at a relatively rapid production rate. The effects of both temperature and rate of draw on the drawn material will also be examined.
A systematic study of the sodium and calcium salts of an ethylene–methacrylic acid copolymer is reported. Fourier-transform infrared spectroscopy (in the midinfrared region) is applied to the characterization of stru...
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A systematic study of the sodium and calcium salts of an ethylene–methacrylic acid copolymer is reported. Fourier-transform infrared spectroscopy (in the midinfrared region) is applied to the characterization of structural changes as a function of temperature and time of annealing. In the spectra of calcium ionomers, bands associated with carboxylate dimers are identified and assignments of specific spectral features to multiplets and clusters are discussed. The spectroscopic changes observed in the spectra of sodium ionomers differ somewhat from their calcium counterparts in that a single infrared band attributed to isolated carboxylate groups is observed. Assignments of specific bands to multiplets and clusters can, however, be made in a manner consistent with the interpretation of the spectra of calcium ionomers.
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