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101.
Global warming is one of the most serious issues in today's world. Various innovative technologies have been proposed for the reduction of CO2 emissions and the mitigation of global warming. They include (1) the WENET project, inaugurated in 1993 by the government of Japan, in which electricity produced by photovoltaic systems in vast areas such as the Sahara Desert, or by hydropower systems, is converted to hydrogen for transport to demand sites, and (2) Steinberg's Hydrocarb process, in which fossil fuels and biomass are coprocessed to produce carbon and methanol. While Japan is resource-poor, it is located relatively close to Southeast Asia and Australia, which are large regions with abundant solar energy. This paper describes an investigation of the prospects for the adoption of these innovative technologies by Japan and surrounding resource regions in the next 30 to 40 years. An optimizing energy model is developed for the purpose, and the simulation results provide several interesting suggestions regarding Japan's future strategy for combatting global warming. 相似文献
102.
A. Cemal Eringen 《International Journal of Engineering Science》1974,12(12):1063-1077
By means of the nonlocal thermodynamics and the axiom of objectivity a set of constitutive equations is developed for the nonlocal thermoelastic solids. Constitutive functionals are linearized, and, together with the balance laws of nonlocal continuum mechanics, the field equations are obtained for the displacement and the temperature fields of the linear theory. The surface physics relevant to thermoelasticity is shown to be included in the theory. 相似文献
103.
Line crack subject to shear 总被引:3,自引:0,他引:3
A. Cemal Eringen 《International Journal of Fracture》1978,14(4):367-379
Field equations of nonlocal elasticity are solved to determine the state of stress in the neighborhood of a line crack in an elastic plate subject to a uniform shear at the surface of the crack tip. A fracture criterion based on the maximum shear stress gives the critical value of the applied shear for which the crack becomes unstable. Cohesive stress necessary to break the atomic bonds is calculated for brittle materials.
The present work was supported by the Office of Naval Research. 相似文献
Résumé Les équations de champ d'élasticité non locale sont résolues afin de déterminer l'état de tension au voisinage d'une fissure linéaire dans une tôle élastique soumise à cisaillement uniforme à la surface de l'extrémité d'une fissure. Un critère de rupture basé sur la tension de cisaillement maximum fournit la valeur critique du cisaillement appliqué, pour lequel la fissure devient instable. La contrainte de cohésion nécessaire pour rompre les liaisons atomiques est calculée dans le cas des matériaux fragiles.
The present work was supported by the Office of Naval Research. 相似文献
104.
105.
In this paper, we propose a novel radio frequency identification (RFID) infrastructure enabling multi-purpose RFID tags realized by the use of privacy preserving public key cryptography (PKC) architecture. The infrastructure ensures that the access rights of the tags are preserved based on the spatial and temporal information collected from the RFID readers. We demonstrate that the proposed scheme is secure with respect to cryptanalytic, impersonation, tracking, replay, and relay attacks. We also analyze the feasibility of PKC implementation on passive class 2 RFID tags, and show that the requirements for PKC are comparable to those of other cryptographic implementations based on symmetric ciphers. Our numerical results indicate PKC based systems can outperform symmetric cipher based systems, since the back end servers can identify RFID tags with PKC based systems approximately 57 times faster than the best symmetric cipher based systems. 相似文献
106.
Sensitivity and specificity of infrared thermography in detection of subclinical mastitis in dairy cows 总被引:1,自引:0,他引:1
The objectives of this experiment were to determine interrelationships among mastitis indicators and evaluate the subclinical mastitis detection ability of infrared thermography (IRT) in comparison with the California Mastitis Test (CMT). Somatic cell count (SCC), CMT, and udder skin surface temperature (USST) data were compiled from 62 Brown Swiss dairy cows (days in milk = 117 ± 51, milk yield = 14.7 ± 5.2 kg; mean ± SD). The CORR, REG, and NLIN procedures of Statistical Analysis System (SAS Institute Inc., Cary, NC) were employed to attain interrelationships among mastitis indicators. The diagnostic merit of IRT as an indirect measure of subclinical mastitis was compared with CMT using the receiver operating characteristics curves. The udder skin surface temperature was positively correlated with the CMT score (r = 0.86) and SCC (r = 0.73). There was an exponential increase in SCC (SCC, ×103 cells/mL = 22.35 × e1.31 × CMT score; R2 = 0.98) and a linear increase in USST (USST, °C = 33.45 + 1.08 × CMT score; R2 = 0.75) as the CMT score increased. As SCC increased, USST increased logarithmically [USST, °C = 28.72 + 0.49 × ln(SCC, ×103 cells/mL); R2 = 0.72]. The USST for healthy quarters (SCC ≤400,000 cells/mL; n = 94) was different from that for subclinical mastitic quarters (SCC >400,000 cells/mL; n = 135) (mean ± SE; 33.45 ± 0.09 vs. 35.80 ± 0.08°C). The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, positive predictive value, and negative predictive value were 95.6, 93.6, 14.97, 0.05, 95.0, and 93.6, respectively, for IRT and 88.9, 98.9, 83.56, 0.11, 99.2, and 86.1, respectively, for CMT. The area under the receiver operating characteristics curve for IRT and CMT was not different. In conclusion, as a noninvasive and quick tool, IRT can be employed for screening subclinical mastitis via measuring USST, with a high predictive diagnostic ability similar to CMT when microbiological culturing is unavailable. However, the reliability of IRT among cows with different characteristics and those living under various environmental conditions remains to be determined. 相似文献
107.
Imine coupled phenolic monomers containing carbazole unit were synthesized in four steps. The monomers were polymerized via oxidative polycondensation by air as oxidant in an aqueous alkaline medium at 50°C. The structures of compounds were confirmed by ultraviolet–visible (UV–vis), Fourier transform infrared, and 1H‐ and 13C‐NMR techniques. The conductivity measurements of these polymers were made by the four‐point probe technique and iodine was used as doping agent. The highest occupied molecular orbital, the lowest unoccupied molecular orbital, and electrochemical and optical band gap values were calculated by the results of the UV–vis and the cyclic voltammetry measurement, respectively. The number‐average molecular weight, weight‐average molecular weight, and polydispersity index values were determined by the size exclusion chromatography technique. Also, thermal behavior of these polymers was determined by thermogravimetric/differential thermal analysis measurements in a N2 atmosphere between 20 and 1000°C. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
108.
Catalytic oxidative polymerization of 2,2′-dihydroxybiphenyl (DHBP) was performed by using Schiff base polymer-Cu (II) complex
and hydrogen peroxide as catalyst and oxidant, respectively. According to size exclusion chromatography (SEC) analysis, the
number-average molecular weight (M
n), weight-average molecular weight (M
w) and polydispersity index (PDI) values of poly (2,2′-dihydroxybiphenyl) (PDHBP) were found to be 37,500, 90,000 g mol−1 and 2.4, respectively. The thermal degradation kinetics was investigated by thermogravimetric analysis in dynamic nitrogen
atmosphere at four different heating rates: 5, 10, 15 and 20 °C min−1. The derivative thermogravimetry curves of PDHBP showed that its thermal degradation process had one weight-loss step. The
apparent activation energies of thermal decomposition for PDHBP as determined by Tang, Flynn–Wall–Ozawa (FWO), Kissenger–Akahira–Sunose
(KAS), Coats–Redfern (CR) and Invariant kinetic parameter (IKP) methods were 109.1, 109.0, 110.0, 108.4 and 109.8 kJ mol−1, respectively. The mechanism function and pre-exponential factor were determined by master plots and Criado–Malek–Ortega
method. The most likely decomposition process was a D
n
Deceleration type in terms of the CR, master plots and Criado–Malek–Ortega results. 相似文献
109.
Merve Küçükoflaz Berna Saraçoğlu Kaya Mustafa Oguzhan Caglayan 《Polymer-Plastics Technology and Engineering》2019,58(7):765-775
In this study, we synthesized poly (vinyl acetate-co-divinyl benzene) microspheres with various monomer/cross-linker contents for oral/topical sustained drug release applications and determined the micromechanical properties by nanoindentation. Compression elastic moduli of materials were calculated by using the limited depth of indentation according to Hertz elastic deformation model and presented as the histogram of multiple data. In terms of drug release practices, poly (VAc-co-DVB) microspheres with a high DVB content, especially in topical applications, are expected to carry drugs under mechanical stresses of less than 1.0 GPa. 相似文献
110.
Güzin Kaban Selen Sallan Kübra Çinar Topçu Bilge Sayın Börekçi Mükerrem Kaya 《International Journal of Food Science & Technology》2022,57(7):4392-4399
The study aims to evaluate the technological properties of autochthonous strains (Lactobacillus sakei S15, Lactobacillus plantarum S24, L. plantarum S91, Pediococcus pentosaceus S128b and Staphylococcus carnosus G109) in Turkish dry fermented sausage (sucuk). After 24 h of fermentaPtion, all lactic acid bacteria strains reduced the pH to below 5.0, while the pH in the control group was above 5.3. The number of lactic acid bacteria strains reached 108–109 cfu g−1 during fermentation. Staphylococcus carnosus G109 remained at the inoculation level of 106 cfu g−1 during ripening. Lactobacillus sakei S15 as mono-culture showed higher TBARS values compared to other strains. The control group had the lowest L* value and autochthonous strains caused no significant difference for a* value. According to principal component analysis results, most volatile compounds were positively correlated with the group containing only L. sakei S15. 相似文献