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排序方式: 共有126条查询结果,搜索用时 15 毫秒
1.
Hong Sae Jin Park Nam Il Hwang Dae Keun Yi Tae Gyu Eum Hyang Lan 《Food science and biotechnology》2022,31(6):669-679
Food Science and Biotechnology - Various hilling materials (rice hulls, pine sawdust, and perlite) were compared to produce sprout vegetables using beach silvertop (Glehnia littoralis Fr. Schm. ex... 相似文献
2.
You Jeong Eum Jungho Ryu Chang Young Koo Jung Min Park Jai-Yeoul Lee Hee Young Lee 《Ceramics International》2021,47(5):6371-6375
Magnetoelectric (ME) property modulation in heterostructured (Ni0.5Zn0.5)Fe2O4/Pt/Pb(Zr0.3Ti0.7)O3 (NZFO/Pt/PZT) thin films on platinized Si substrate by thermal annealing condition variation was studied. In an attempt to prevent interfacial reaction between NZFO and PZT layers during high temperature annealing, thin Pt layer was deposited which can serve as inter-diffusion barrier as well as electrode. The ferroelectric, magnetic, and ME properties of the heterostructured film were noticeably modulated due to microstructural evolution and clamping relaxation developed during thermal annealing process. Room temperature ME voltage coefficient of the heterostructured thin films was enhanced with increasing annealing temperature and reached to 29 mV/cm·Oe when annealed at 650 °C. 相似文献
3.
Seok-June Chae Dae-Su Kim Hero Kim Su-Hwan Go Sun-Woo Kim Eun-Ji Kim Jae-Min Eum In-Su Kim Sahn Nahm 《Journal of the American Ceramic Society》2022,105(2):1185-1197
0.97(Na0.5-xLixK0.5)(Nb0.89Sb0.11)O3-0.03CaZrO3 [(N0.5-xLxK)(NS)-CZ] piezoceramic (x = 0.325) has a pseudocubic-tetragonal-orthorhombic (PC-T-O) multi-structure. The PC structure formed in this piezoceramic was identified as the R3m rhombohedral structure. This piezoceramic showed the large piezoelectric charge constant (d33) of 515 pC/N due to the PC-T-O multi-structure. The NaNbO3 (NN) templates were used to texture the (N0.5-xLxK)(NS)-CZ thick films along the (001) direction, and the textured thick film (x = 0.0375) had a large Lotgering factor of 95.6%. The PC-T-O multi-structure was observed in this thick film (x = 0.0375), but the thick film (x = 0.0325) showed a PC-O structure owing to the diffusion of the NN templates into the thick film. The textured thick film (x = 0.0375) exhibited an increased d33 of 625 pC/N because of the PC-T-O multi-structure and the lineup of grains along the [001] direction. A textured thick film (x = 0.0375) was used to fabricate a planar-type actuator to confirm its applicability to electrical devices. This actuator exhibits large acceleration (580.3 G) and displacement (150 μm) at a low electric field of 0.2 kV/mm with a short response time of 3.0 ms. Therefore, the (N0.5-xLxK)(NS)-CZ thick films are excellent lead-free piezoceramics. 相似文献
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This paper suggests a new method to search main path, as a knowledge trajectory, in the citation network. To enhance the performance and remedy the problems suggested by other researchers for main path analysis (Hummon and Doreian, Social Networks 11(1): 39–63, 1989), we applied two techniques, the aggregative approach and the stochastic approach. The first technique is used to offer improvement of link count methods, such as SPC, SPLC, SPNP, and NPPC, which have a potential problem of making a mistaken picture since they calculate link weights based on a individual topology of a citation link; the other technique, the second-order Markov chains, is used for path dependent search to improve the Hummon and Doreian’s priority first search method. The case study on graphene that tested the performance of our new method showed promising results, assuring us that our new method can be an improved alternative of main path analysis. Our method’s beneficial effects are summed up in eight aspects: (1) path dependent search, (2) basic research search rather than applied research, (3) path merge and split, (4) multiple main paths, (5) backward search for knowledge origin identification, (6) robustness for indiscriminately selected citations, (7) availability in an acyclic network, (8) completely automated search. 相似文献
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Novel polypyrrole (PPy)/polydimethylsiloxane (PDMS) composite membrane was prepared by interfacial polymerization to make a very effective gas separation membrane. We found that Polymerized PPy films as thin as ~200 nm could be chemically synthesized as freestanding membranes by using the interfacial polymerization technique. Additionally, we show that difference morphology of PPys films was obtained by controlling polymerization rate and more dense films were formed at low polymerization rate. Wide X-ray diffraction study showed the d spacing value of the PPy film decreased from 4.89 å to 3.67 å by the rate of polymerization decreases. According to d spacing value decrease, selectivity of a PPy composite membrane was increased dramatically and permeability was reduced gradually. This high selectivity was derived from d spacing closed to the kinetic diameter of nitrogen. These results indicated that the permeability is controlled by the diffusion coefficient, reflecting the packed structure of the PPy film. The highest selectivity value of composite membrane that was prepared by interfacial polymerization was O2/N2=17.2 and permeability for O2 was 40.2 barrer. 相似文献
8.
Hoang Long Le Jinki Jeong Banshi D. Pandey Jae-Min Yoo Trung Hai Huyunh 《Mineral Processing and Extractive Metallurgy Review》2013,34(2):90-104
Present paper focuses on the selective recovery of copper from the enriched ground printed circuit boards (PCBs) using leaching and solvent extraction. The metal-enriched ground sample obtained from the beneficiation of the sized PCBs in a laboratory scale column type air separator contained mainly 49.3% Cu, 3.83% Fe, 1.51% Ni, 5.45% Sn, 4.71% Pb, and 1.85% Zn. The leaching of the enriched sample with 3.5 mol/L nitric acid dissolved 99% copper along with other metals at 323 K temperature and 120 g/L pulp density in 1 h time. The composition of the leach liquor with wash solution was found to be 42.11 g/L Cu, 2.12 g/L Fe, 4.02 g/L Pb, 1.58 g/L Zn, and 0.4 g/L Ni. The McCabe–Thiele plot indicated the requirements of three counter-current stages for maximum extraction of copper from the leach liquor at pH 1.5 using 30, 40, and 50% (v/v) LIX 984 N at the phase ratios (A/O) of 1:3, 1:2, and 1:1.5, respectively. The counter-current simulation studies show the selective extraction of 99.7% copper from the leach liquor feed of 1.5 pH in three stages with 50% LIX 984 N at A/O phase ratio of 1:1.5. The stripping of copper from the loaded organic with sulfuric acid produced copper sulfate solution from which copper metal/powder could be recovered by electrolysis/ hydrogen reduction. 相似文献
9.
Hyung-Won Kim Jae-Min Yu Ji-Su Kim Hyoung-Ho Doh Dong-Ho Lee Sung-Ho Nam 《The International Journal of Advanced Manufacturing Technology》2012,58(5-8):683-691
This paper considers the loading problem for flexible manufacturing systems with highly flexible partial machine grouping, i.e., machines are tooled differently, but each operation can be assigned to multiple machines. Loading is the problem of allocating operations and their associated cutting tools to machines for a given set of parts. As an extension of the existing studies, we consider unrelated machines, i.e., processing time of an operation depends on the speed of the machine to which it is allocated, and dedicated machines, i.e., certain part types must be processed on a specific machine. Also, we consider the constraints associated with cutting tools: (a) tool life restrictions and (b) number of available tool copies. An integer linear programming model is suggested for the objective of balancing the workloads assigned to machines and then due to the complexity of the problem, we suggest two-stage heuristics in which an initial solution is obtained using modified bin-packing algorithms and then it is improved by a simple search technique. The two-stage heuristics suggested in this study were tested on various test instances, and the results show that they can give reasonable quality solutions within a very short amount of computation time. Also, a sensitivity analysis was done on the tightness of the tooling constraints, and the results are reported. 相似文献
10.
Sun-Woo Kim Seok-June Chae Dae-Su Kim Jong-Un Woo Eun-Ji Kim Su-Hwan Go Jae-Min Eum Hyung-Won Kang Seung Ho Han Sahn Nahm 《Journal of the American Ceramic Society》2023,106(1):488-500
High-power piezoelectric energy harvesters (PEHs) require piezoceramics with a large kp and d33 but small εT33/ε0 values. The [0 0 1]-textured 0.96(Na, K)(Nb1−xSbx)–0.04SrZrO3 piezoceramics (x = 0.025 and 0.045) exhibited the improved electromechanical coupling factor (kp) and piezoelectric charge constant (d33); however, the increase of dielectric constant (εT33/ε0) was not significant. Further, the textured piezoceramic with x = 0.045 shows the large d33 × g33 value of 21.5 pm2/N, where g33 is piezoelectric voltage constant, indicating that texturing is a good technique to fabricate the piezoceramics for PEH. The impedance curve of the PEH consisting of the metal substrate and textured piezoceramic shows a piezoelectric resonance peak at a low frequency, which is the same as the mechanical resonance frequency of the PEH. Hence, the PEH can be considered a piezoelectric material. The figure of merit of the PEH was determined using the mechanical quality and electromechanical coupling factor calculated from the impedance curve of the PEH. A large power output of 1.7 mW was obtained from the type-1 PEH at the resonance frequency produced using the textured thick film (x = 0.045). Hence, this PEH can be used as a permanent power source for microelectronic devices in the Internet of Things. 相似文献