The Experts below are selected from a list of 177 Experts worldwide ranked by ideXlab platform
M.x. Pan - One of the best experts on this subject based on the ideXlab platform.
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Room Temperature Table-like magnetocaloric effect in amorphous Gd50Co45Fe5 ribbon
Journal of Physics D: Applied Physics, 2016Co-Authors: G L Liu, Dongshan Zhao, H Y Bai, Weihua Wang, M.x. PanAbstract:Gd50Co45Fe5 amorphous alloy ribbon with a Table-like magnetocaloric effect (MCE) suiTable for the ideal Ericsson cycle at room Temperature has been developed. In addition to a high magnetic transition Temperature of 289 K very close to that of Gd (294 K), a relatively large value of refrigerant capacity (~521 J kg−1) has been achieved under a field change of 5 T. This value of refrigerant capacity (RC) is about 27% and 70% larger than those of Gd (~410 J kg−1) and Gd5Si2Ge2 (~306 J kg−1). More importantly, the peak value of magnetic entropy change () approaches a nearly constant value of ~3.8 J ⋅ kg−1 ⋅ K−1 under an applied field change of 0~5 T in a wide Temperature span over 40 K around room Temperature, which could be used as the candidate working material in the Ericsson-cycle magnetic regenerative refrigerator around room Temperature.
G L Liu - One of the best experts on this subject based on the ideXlab platform.
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Room Temperature Table-like magnetocaloric effect in amorphous Gd50Co45Fe5 ribbon
Journal of Physics D: Applied Physics, 2016Co-Authors: G L Liu, Dongshan Zhao, H Y Bai, Weihua Wang, M.x. PanAbstract:Gd50Co45Fe5 amorphous alloy ribbon with a Table-like magnetocaloric effect (MCE) suiTable for the ideal Ericsson cycle at room Temperature has been developed. In addition to a high magnetic transition Temperature of 289 K very close to that of Gd (294 K), a relatively large value of refrigerant capacity (~521 J kg−1) has been achieved under a field change of 5 T. This value of refrigerant capacity (RC) is about 27% and 70% larger than those of Gd (~410 J kg−1) and Gd5Si2Ge2 (~306 J kg−1). More importantly, the peak value of magnetic entropy change () approaches a nearly constant value of ~3.8 J ⋅ kg−1 ⋅ K−1 under an applied field change of 0~5 T in a wide Temperature span over 40 K around room Temperature, which could be used as the candidate working material in the Ericsson-cycle magnetic regenerative refrigerator around room Temperature.
Scot Campbell - One of the best experts on this subject based on the ideXlab platform.
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A novel Smiles rearrangement gives access to the A-ring pyridine isomers of the nevirapine ring system
The Journal of Organic Chemistry, 1993Co-Authors: John R. Proudfoot, Usha R. Patel, Scot CampbellAbstract:The cyclization of N-methylamide 9 gives, along with the expected product 2, the isomeric diazepinone 3 resulting from a novel Smiles rearrangement in which an N-methylcarboxamide functions as a leaving group. The mechanism of the reaction has been proven by isolation of the intermediate 10 and by conducting the rearrangement on the model compound 13. The relative amounts of 2, 3, and 10 formed from 9 are subject to some control by variation of the base and reaction Temperature (Table I). This new Smiles rearrangement was applied to the synthesis of the remaining two A-ring isomers 4 and 5 of the nevirapine ring system 1 by cyclization of the thioether 16 and the sulfoxide 17
Wolfgang Wagner - One of the best experts on this subject based on the ideXlab platform.
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Tables of the Properties of Water and Steam
International Steam Tables, 2019Co-Authors: Hans-joachim Kretzschmar, Wolfgang WagnerAbstract:This Chapter contains the following Tables: Table 1 Saturation state (Temperature Table): Thermodynamic and transport properties Table 2 Saturation state (Pressure Table): Thermodynamic properties Table 3 Single-phase region: Thermodynamic and transport properties Table 4 High-Temperature region: Thermodynamic properties Table 5 Ideal-gas state: Thermodynamic properties Table 6 Saturation state: Compression factor, Specific isochoric heat capacity, Isobaric cubic expansion coefficient, Isothermal compressibility Table 7 Compression factor Table 8 Specific isochoric heat capacity Table 9 Isobaric cubic expansion coefficient Table 10 Isothermal compressibility Table 11 Saturation state: Kinematic viscosity, Prandtl number, Thermal diffusivity, Dielectric constant Table 12 Kinematic viscosity Table 13 Prandtl number Table 14 Thermal diffusivity Table 15 Dielectric constant Table 16 Refractive index (Saturation state) Table 17 Refractive index Table 18 Saturation state: Relative pressure coefficient, Isothermal stress coefficient, Fugacity Table 19 Relative pressure coefficient Table 20 Isothermal stress coefficient Table 21 Fugacity Table 22 Saturation state: Joule-Thomson coefficient, Isothermal throttling coefficient, Surface tension Table 23 Joule-Thomson coefficient Table 24 Isothermal throttling coefficient
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Saturation State (Temperature Table)
Properties of Water and Steam Zustandsgrößen von Wasser und Wasserdampf, 1998Co-Authors: Wolfgang Wagner, Alfred KruseAbstract:The Temperature Table of the saturation states contains values for the saturated liquid (′) and saturated vapour (″) of the following thermophysical properties in the Temperature range from 0 °C to the critical Temperature t c = 373.946 °C: Saturation pressure p s Specific volume v Specific enthalpy h Specific entropy of evaporation Δh v Specific entropy s Specific entropy of evaporation Δs v Specific isobaric heat capacity c p Speed of sound w Isentropic exponent K Dynamic viscosity ŋ Thermal conductivity λ.
Wenguang Liu - One of the best experts on this subject based on the ideXlab platform.
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a mechanically strong highly sTable thermoplastic and self healable supramolecular polymer hydrogel
Advanced Materials, 2015Co-Authors: Xiyang Dai, Lina Gao, Yinyu Zhang, Yuanlu Cui, Tao Bai, Wenguang LiuAbstract:DOI: 10.1002/adma.201500534 the concomitant strengthening effect shown in condensed matters in polar media. [ 11 ] It is known that the secondary structure of proteins is held together by hydrogen bonding between the C O and N H groups, and hydrogen-bonded clusters contribute to their unique native structures. [ 12,13 ] As the smallest species of the 20 amino acids found in proteins, glycine is unique since it can fi t into hydrophilic or hydrophobic settings. Although O H···N hydrogen bonds can be formed, this interaction is unsTable in water and therefore cannot be used to enhance mechanical strength. In the work reported by Tobias et al. on the stability of a model β-sheet in water, the binding free energies of two intermolecular hydrogen bonds and single amide hydrogen bond in the model β-sheet were calculated to be −5.5 and −0.34 kcal mol −1 , respectively, suggesting dual hydrogen bonds are quite sTable while a simple amide hydrogen bond is only marginally sTable. [ 14 ] Inspired by this theoretical basis and aiming to amplify the hydrogen bonding interaction of the simplest amino acid, glycine, we proposed to transform glycinamide (amidated glycine), which consists of two amides, into a polymerizable monomer, N -acryloyl glycinamide (NAGA, Scheme 1 A), by reacting glycinamide with acryloyl chloride using a reported method. [ 15,16 ] N -acryloyl glycinamide can be directly and conveniently initiated in water to form poly( N acryl oyl glycinamide) (PNAGA). From the molecular structure of PNAGA depicted in Scheme 1 A, we envisioned that a concentrated aqueous solution of poly( N -acryloyl glycinamide) could form a high-strength supramolecular polymer hydrogel due to the strong physical crosslinking stemming from the highly sTable hydrogen bonded interaction domains formed among dual amide motifs in the side chain. To verify our hypothesis, we prepared different concentrations of NAGA aqueous solutions, which were then photoinitiated at room Temperature (Table S1). We found that at 1% and 2% NAGA, the polymer solutions were in the sol state, but gelation occurred when concentration was raised to 3%, as verifi ed with the inverted vial method (Figure S5, Supporting Information). The prepared hydrogels were immersed in deionized and distilled water for 7 d, and equilibrium water contents (EWCs) were determined (Figure S6, Supporting Information). Unexpectedly, after reaching swelling equilibrium, the EWCs of the gels initially made with 10–25 wt% NAGA decrease by varied amounts compared with the water contents of the respective original hydrogels. It is possible that the hydrogen bondings among dual amides may reorganize and intensify to result in an increased crosslinking density after the gels are re-immersed in water. PNAGA-30, made with 30% NAGA initially, showed only a slight increase in its EWC. In this case, the hydrogen-bonded supramolecular interactions started to achieve a saturated state. In spite of the increased water content after equilibrium Over the past decade, high strength hydrogels have received growing interest due to their great potential for extended use in load-bearing applications. Many strategies have been explored to enhance the tensile strength, the compressive strength or toughness of hydrogels, including double network, [ 1 ] topological sliding network, [ 2 ] composite reinforcement, [ 3 ] and covalent/ ionic crosslinking mechanisms. [ 4 ] Despite this, development of a hydrogel with high comprehensive mechanical properties that are not weakened by soaking in aqueous media remains challenging. [ 5 ] Since chemical crosslinkers are generally essential for the construction of high-strength hydrogels, the resultant gels tend not to be recyclable or reprocessable. Our group recently reported on hydrogels strengthened by diaminotriazine-diaminotriazine (DAT-DAT) hydrogen bonding, which demonstrated both high tensile and compressive strengths and exceptional stability in aqueous solution due to the formation of sTable DAT-DAT hydrogen bonding domains. [ 6 ] These H-bonding hydrogels were typically synthesized from photoinitated copolymerization of 2-vinyl-4,6-diamino-1,3,5-triazine (VDT) and polyethylene glycol diacrylate in DMSO, which was required to solubilize VDT. These chemically crosslinked PVDT-based organogels were then soaked in water to replace DMSO, converting the organogels into hydrogels and re-establishing cooperative DAT-DAT hydrogen bonding interaction which tremendously increased the mechanical strengths of the resultant fully swollen hydrogel. Nonetheless, the organic solvent needed to make these gels is not environmentally benign. The hydrogen bonding is commonly a weak noncovalent bond, though their cooperative interaction can result in the strength of a covalent bond. [ 7 ] However, most hydrogen bonds only exhibit this strength in nonpolar organic solvents, with their strengthening effect severely discounted in polar solvents. [ 8,9 ] The remarkable reinforcement effect of DAT-DAT hydrogen bonding originates from the formation of sTable hydrogen-bonded microdomain clusters. [ 6a , 10 ] This principle suggests that the formation of H-bonding microdomains is required for the sTable existence of robust H-bonds, as well as
