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排序方式: 共有2347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.
Eui Dae Jung Amit Kumar Harit Do Hui Kim Chung Hyeon Jang Jong Hyun Park Shinuk Cho Myoung Hoon Song Han Young Woo 《Advanced materials (Deerfield Beach, Fla.)》2020,32(30):2002333
A series of anionic conjugated polyelectrolytes (CPEs) is synthesized based on poly(fluorene-co-phenylene) by varying the side-chain ionic density from two to six per repeat units (MPS2-TMA, MPS4-TMA, and MPS6-TMA). The effect of MPS2, 4, 6-TMA as interlayers on top of a hole-extraction layer of poly(bis(4-phenyl)-2,4,6-trimethylphenylamine (PTAA) is investigated in inverted perovskite solar cells (PeSCs). Owing to the improved wettability of perovskites on hydrophobic PTAA with the CPEs, the PeSCs with CPE interlayers demonstrate a significantly enhanced device performance, with negligible device-to-device dependence relative to the reference PeSC without CPEs. By increasing the ionic density in the MPS-TMA interlayers, the wetting, interfacial defect passivation, and crystal growth of the perovskites are significantly improved without increasing the series resistance of the PeSCs. In particular, the open-circuit voltage increases from 1.06 V for the PeSC with MPS2-TMA to 1.11 V for the PeSC with MPS6-TMA. The trap densities of the PeSCs with MPS2,4,6-TMA are further analyzed using frequency-dependent capacitance measurements. Finally, a large-area (1 cm2) PeSC is successfully fabricated with MPS6-TMA, showing a power conversion efficiency of 18.38% with negligible hysteresis and a stable power output under light soaking for 60 s. 相似文献
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In vivo Kinetic Biodistribution of Nano‐Sized Outer Membrane Vesicles Derived from Bacteria
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Su Chul Jang Sae Rom Kim Yae Jin Yoon Kyong‐Su Park Ji Hyun Kim Jaewook Lee Oh Youn Kim Eun‐Jeong Choi Dae‐Kyum Kim Dong‐Sic Choi Yoon‐Keun Kim Jaesung Park Dolores Di Vizio Yong Song Gho 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(4):456-461
Evaluation of kinetic distribution and behaviors of nanoparticles in vivo provides crucial clues into their roles in living organisms. Extracellular vesicles are evolutionary conserved nanoparticles, known to play important biological functions in intercellular, inter‐species, and inter‐kingdom communication. In this study, the first kinetic analysis of the biodistribution of outer membrane vesicles (OMVs)—bacterial extracellular vesicles—with immune‐modulatory functions is performed. OMVs, injected intraperitoneally, spread to the whole mouse body and accumulate in the liver, lung, spleen, and kidney within 3 h of administration. As an early systemic inflammation response, increased levels of TNF‐α and IL‐6 are observed in serum and bronchoalveolar lavage fluid. In addition, the number of leukocytes and platelets in the blood is decreased. OMVs and cytokine concentrations, as well as body temperature are gradually decreased 6 h after OMV injection, in concomitance with the formation of eye exudates, and of an increase in ICAM‐1 levels in the lung. Following OMV elimination, most of the inflammatory signs are reverted, 12 h post‐injection. However, leukocytes in bronchoalveolar lavage fluid are increased as a late reaction. Taken together, these results suggest that OMVs are effective mediators of long distance communication in vivo. 相似文献
5.
Bong Keun Kim Wan Kyun Chung 《Industrial Electronics, IEEE Transactions on》2003,50(6):1207-1216
Disturbance-observer (DOB)-based controller design is one of the most popular methods in the field of motion control. In this paper, the generalized disturbance compensation framework, named the robust internal-loop compensator (RIC) is introduced and an advanced design method of a DOB is proposed based on the RIC. The mixed sensitivity optimization problem, which is the main issue of DOB design, is also solved through the parametrization of the DOB in the RIC framework. Differently from conventional methods, the Q-filter is separated from the mixed sensitivity optimization problem and a systematic design law for the DOB is proposed. This guarantees the robustness and optimality of the DOB and enables the design for unstable plants. 相似文献
6.
An experimental study was conducted to investigate the rheological behavior of a heterogeneous polymer blend system consisting of nylon 6 and an ethylene-based multifunctional polymer (CXA 3101, DuPont Co.). For comparison purposes, we also investigated the rheological behavior of two additional blend systems, namely blends of nylon 6 with a chemically modified polyolefin (Plexar 3, Chemplex Co.) and blends of nylon 6 with ethylene–vinyl acetate copolymer (EVA). We have investigated the thermal and thermomechanical behavior of the blend systems, using differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). Also, we have attempted to identify the chemical structure of the functional groups present in the CXA 3101 and Plexar 3 resins, using infrared (IR) spectroscopy. This information has enabled us to interpret the observed rheological behavior. Furthermore, we have used both optical and scanning electron microscopies to investigate the state of dispersion of the constituent components in each of the blend systems. We have concluded that, during melt blending, chemical reactions have taken place between carboxyl or anhydride groups present in the CXA 3101 resin and the amino end groups of the nylon 6, forming a graft copolymer which then acted as an “interfacial agent.” 相似文献
7.
Random vibration analysis of flexible rotor-bearing systems subjected to six-component nonstationary earthquake ground accelerations is carried out. The rotor system consists of several rigid disks and a flexible shaft that is modelled as a Timoshenko beam. The governing equations of motion involve both inhomogeneous random excitations and random parametric excitations. Analytically, the Markov vector approach using the Ito equation and Stratonovich averaging procedures is employed to determine the response statistics. Unfortunately, the second moments of the response quantities thus obtained involve a great discrepancy when compared with the results of Monte Carlo simulation. The difficulty involved in analytically solving such a complicated problem is pointed out. Currently, the method of Monte Carlo simulation appears to be the only practical approach for such a problem. The significant influence of the seismic base rotations and the flexibility of the rotor-bearing system on the overall dynamic structural response is demonstrated by a numerical example. 相似文献
8.
Sang-Hoon Lee Dae Hwan Kim Kyung Rok Kim Jong Duk Lee Byung-Gook Park Young-Jin Gu Gi-Young Yang Jeong-Taek Kong 《Nanotechnology, IEEE Transactions on》2002,1(4):226-232
A practical model for a single-electron transistor (SET) was developed based on the physical phenomena in realistic Si SETs, and implemented into a conventional circuit simulator. In the proposed model, the SET current calculated by the analytic model is combined with the parasitic MOSFET characteristics, which have been observed in many recently reported SETs formed on Si nanostructures. The SPICE simulation results were compared with the measured characteristics of the Si SETs. In terms of the bias, temperature, and size dependence of the realistic SET characteristics, an extensive comparison leads to good agreement within a reasonable level of accuracy. This result is noticeable in that a single set of model parameters was used, while considering divergent physical phenomena such as the parasitic MOSFET, the Coulomb oscillation phase shift, and the tunneling resistance modulated by the gate bias. When compared to the measured data, the accuracy of the voltage transfer characteristics of a single-electron inverter obtained from the SPICE simulation was within 15%. This new SPICE model can be applied to estimating the realistic performance of a CMOS/SET hybrid circuit or various SET logic architectures. 相似文献
9.
In this paper damage propagation during metal forming process is investigated with the concept of continuum damage mechanics. An isotropic damage model based on the theory of materials of type N is adopted to describe the damage process of a ductile material with large elasto-viscoplastic deformation. To solve the finite elasto-viscoplasticity problem, a reasonable kinematic strain measure for largely deformed solids is used and the damage constitutive equations based on thermodynamical framework are developed. The stiffness degradation of the loaded material is chosen as a damage measure. An extended interior penalty method is used to impose the contact condition on the boundary. The highly nonlinear equilibrium equations are reduced to the incremental weak form and approximated by the total Lagrangian finite element method. The displacement control method along with the modified Riks' continuation technique based on displacement parameter is used to solve the incremental iterative equations. As numerical examples, upsetting, backward extrusion and punch problems are simulated and the results of damage propagation and J2 stress contours with and without damage are presented. For punch problems, spring back and residual stresses are also presented. 相似文献
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