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991.
992.
Jiabin Liu Jiawei Deng Yangyang Zhu Xiaokang Geng Lifu Zhang Sang Young Jeong Dan Zhou Han Young Woo Dong Chen Feiyan Wu Lie Chen 《Advanced materials (Deerfield Beach, Fla.)》2023,35(1):2208008
With the great potential of the all-polymer solar cells for large-area wearable devices, both large-area device efficiency and mechanical flexibility are very critical but attract limited attention. In this work, from the perspective of the polymer configurations, two types of terpolymer acceptors PYTX-A and PYTX-B (X = Cl or H) are developed. The configuration difference caused by the replacement of non-conjugated units results in distinct photovoltaic performance and mechanical flexibility. Benefiting from a good match between the intrinsically slow film-forming of the active materials and the technically slow film-forming of the blade-coating process, the toluene-processed large-area (1.21 cm2) binary device achieves a record efficiency of 14.70%. More importantly, a new parameter of efficiency stretchability factor (ESF) is proposed for the first time to comprehensively evaluate the overall device performance. PM6:PYTCl-A and PM6:PYTCl-B yield significantly higher ESF than PM6:PY-IT. Further blending with non-conjugated polymer donor PM6-A, the best ESF of 3.12% is achieved for PM6-A:PYTCl-A, which is among the highest comprehensive performances. 相似文献
993.
Hanjun Hwangbo Hyeongjin Lee Eun-Ju Jin Yunju Jo Jigyeong Son Han Min Woo Dongryeol Ryu Geun Hyung Kim 《Advanced functional materials》2023,33(10):2209157
Tissue engineering strategies using cell-laden constructs have shown promising results in the treatment of various types of damaged tissues. However, inadequate oxygen delivery to the macroscale 3D cell-constructs for regenerating skeletal muscle tissue has remained a multiplex issue owing to the pivotal factors including cell metabolism and several regulatory intercellular pathways that eventually influence various cellular activities and determines cell phenotype. To overcome this issue, a photosynthetic cyanobacterium (Synechococcus elongatus) is employed in a methacrylated gelatin bioink. Furthermore, to effectively induce cell alignment in the bioink, in situ electric field stimulation is used in a bioprinting system to fabricate cell-laden scaffolds for regenerating skeletal muscle tissue. Owing to the synergistic effects of the bioactive microenvironment that rescues cells from hypoxic conditions and activations of voltage-gated ion channels, highly aligned, multi-nucleated myofibers are obtained as well as significant upregulation (7–10-fold) of myogenic-related genes compared with conventionally prepared cell-constructs. In addition, in vivo studies using a mouse volumetric muscle loss model demonstrate considerable restoration of muscle functionality and regeneration. 相似文献
994.
Kang Cholmin Yeom Inhwa Ashtari Amirsaman Woo Woontack Noh Junyong 《Virtual Reality》2023,27(3):1919-1936
Virtual Reality - Engaging in outdoor daily activities such as shopping is an essential, yet challenging activity for older wheelchair users (OWU). However, little is investigated on how to augment... 相似文献
995.
Eunsoo Jung Woo Kwon Jung Su‐Bin Park Hyung Rae Kim Junghyun Kim 《Food Science & Nutrition》2020,8(6):2895-2903
Neovascularization in the retina is common pathophysiology of diabetic retinal microvasculopathy and exudative macular degeneration. Our study assessed the inhibitory activity of an ethanol‐based extract of Aucuba japonica (AJE) on abnormal angiogenesis in the retina with a hyperoxia‐induced neovascular retinopathy model. The inhibitory effects of aucubin, quercetin, and kaempferol, bioactive compounds, from A. japonica, on retinal vascular hyperpermeability were also examined. On the 7th postnatal day (P7), the C57BL/6 pups were exposed to a hyperoxic environment with 75% oxygen to develop the experimental angiogenesis in retinas. On the 12th postnatal day (P12), the pups were then returned to the normal atmospheric pressure of oxygen. From P12 to P16, the administration was intraperitoneal. The dose per day was 250 mg per kg weight. Retinal neovascularization was measured with retinal flat mounts prepared on P17. We also measured the vascular leakage mediated by the vascular endothelial growth factor (VEGF) in retinas. Mice treated with AJE had markedly smaller neovascular lesions, in comparison with vehicle‐administered mice. AJE downregulated the expression of both VEGF protein and mRNA. In addition, aucubin, quercetin, and kaempferol ameliorated VEGF‐induced retinal vascular leakage. The results of our study suggest that AJE is a potent antiangiogenic substance. AJE could also serve as a therapeutic agent for abnormal growth of vessels in the retina in patients with ischemic retinopathy. The bioactive compounds of AJE may be responsible for its antiangiogenic abilities. 相似文献
996.
Chengyun Hong;Vu Khac Dat;Minh Chien Nguyen;Woo Jong Yu;Ji-Hee Kim; 《Advanced functional materials》2024,34(46):2407821
The van der Waals (vdW) contact, characterized by its bondless interactions, opens up exciting possibilities in cutting-edge mask technology. It enables incredibly close proximity to samples at the atomic level while facilitating non-destructive engineering. In this study, the concept of a vdW metal mask using the template striped ultra-flat Ag/Au film is introduced. The probe tip-assisted metal film transfer under an optical microscope is employed to showcase all-solid and residue-free engineering on 2D materials. The robust nature of the vdW metal mask allows for various treatments, including gas, liquid, solid, plasma, and light, making it a universal tool for fabricating 2D material-based devices and samples with sub-1 µm resolution, all without the need for lithography technologies. With the superiority in simple sample fabrication, ultra-clean surfaces, and robustness under harsh conditions, the technique is believed to flourish in the 2D material research field. 相似文献
997.
Tae Yoon Lee Myeong Seop Song Jung Woo Cho In Hyeok Choi Chihwan An Jong Seok Lee Seung Chul Chae 《Advanced Electronic Materials》2024,10(2):2300591
Ferroelectric materials are promising candidates for neuromorphic computing synaptic devices due to the nonvolatile multiplicity of spontaneous polarization. To ensure a sufficient memory window, ferroelectric materials with a large coercivity are urgently required for practical applications in highly scaled multi-bit memory devices. Herein, a remarkable reliability of intermediate ferroelectric polarization states is demonstrated in a textured Al0.66Sc0.34N thin film with a coercive field of 2.4 MV cm−1. Al0.66Sc0.34N thin films are prepared at 300 °C on Pt (111)/Ti/SiO2/Si substrates using a radio frequency reactive sputtering method. Al0.66Sc0.34N thin films exhibit viable ferroelectricity with a large remanent polarization value of >100 µC cm−2. Through the conventional current–voltage characteristics, polarization switching kinetics, and temperature dependence of coercivity, the reproducibility of multiple polarization states with apparent accuracy is attributed to a small critical volume (3.7 × 10−28 m3) and a large activation energy (3.3 × 1027 eV m−3) for nucleation of the ferroelectric domain. This study demonstrates the potential of ferroelectric Al1-xScxN for synaptic weight elements in neural network hardware. 相似文献
998.
Yong‐Woo Shin Hisayuki Nakatani Toshiya Uozumi Boping Liu Tsuneji Sano Koh‐hei Nitta Minoru Terano 《Polymer International》2003,52(1):29-34
During propylene polymerization with the Cr(acetylacetonate)3/MgCl2–Et2AlCl–ethylbenzoate catalyst system which shows high isospecificity for propylene polymerization, it was found that the chain transfer and termination reactions can be neglected. Based on this result, some stepwise polymerizations of propylene and ethylene were carried out with the same catalyst system varying polymerization conditions. The resulting copolymers were separated by temperature rising elution fractionation (TREF) and afforded two fractions which were eluted at different temperatures. From the 13C NMR, DSC and GPC analyses of each fraction, it was considered that the corresponding block copolymer existed in the fraction eluted at higher temperature. © 2003 Society of Chemical Industry 相似文献
999.
1000.
Modified atmosphere packages were designed and used for the packaging of green chili peppers. Respiration of green peppers at 10°C was characterized by the closed-system method as a function of O2 and CO2 concentrations, and was incorporated into mass balance equations of O2 and CO2 gases in order to predict the gas composition inside the package over time. From the prediction of atmospheres inside packages constructed of the available plastic films, three retail packages (110-g peppers) were designed and studied experimentally for their ability to modify the package atmosphere and to retain quality (moisture, ascorbic acid and chlorophyll). Pepper packages using 25 μm low-density polyethylene and 30 μm cast polypropylene could attain modified atmosphere close to the optimal gas concentrations (3% O2 and 5% CO2), and therefore provided better quality retention compared with unpackaged controls. 相似文献