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991.
Wood has limitations in strength because of its biostructural defects, including vessels. To overcome this limitation, composite materials can be innovated by breaking wood down into cellulose and lignin and reassembling them for bio‐originating strong structural materials. In this study, an ecofriendly resin was developed that was suitable for cellulose‐based composites. To overcome the low dimensional stability of lignin and to increase its interactions with cellulose, it was blended with poly(vinyl alcohol) (PVA). The PVA–lignin resin was characterized with scanning electron microscopy, Fourier transform infrared spectroscopy, thermal analysis, mechanical tensile testing, and lap‐shear joint testing. The adhesion properties of the PVA–lignin resin increased with increasing PVA content. PVA played the role of synthetic polymer and that of linker between the cellulose and lignin, like hemicellulose does in wood. The PVA–lignin resin exhibited a high miscibility, mechanical toughness, and good adhesion properties for nanocellulose composites. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46655. 相似文献
992.
Ko Hoon Kim Hye Ran Moon Junseong Lee Jimin Kim Jae Nyoung Kim 《Advanced Synthesis \u0026amp; Catalysis》2015,357(7):1532-1544
The Wittig reaction of isatin derivatives with Morita–Baylis–Hillman bromides of cinnamaldehydes afforded 3‐dienylidene‐2‐oxindoles. These trienes were converted into the corresponding spirooxindoles in a stereoselective manner in refluxing toluene in good yields. The diastereomeric spirooxindoles could be obtained stereoselectively by adding a catalytic amount of palladium(II) acetate via the palladium‐catalyzed isomerization of EEE‐trienes to ZEE‐trienes followed by a more facile 6π‐electrocyclization process. The obtained spirooxindoles could be further functionalized by palladium‐catalyzed oxidative arylation, thionation with Lawesson’s reagent, catalytic hydrogenation and Friedel–Crafts‐type reaction.
993.
Screening,Synthesis, and In Vitro Evaluation of Vinyl Sulfones as Inhibitors of Complement‐Dependent Cytotoxicity in Neuromyelitis Optica 下载免费PDF全文
Eun Ji Ju Seul Ki Yeon Dr. Jong‐Hyun Park Dr. So Young Cheon Ji Won Choi Dr. Taehwan Ha Bo Ko Jang Siwon Kim Yong Gu Kang Dr. Hayoung Hwang Dr. Sung Jin Cho Prof. Eunji Cheong Prof. Yong Sun Bahn Dr. Ae Nim Pae Prof. Sung Min Kim Dr. Ki Duk Park 《ChemMedChem》2016,11(4):377-381
Neuromyelitis optica (NMO) is a demyelinating autoimmune disease of the optic nerve and spinal cord triggered by binding of NMO‐specific immunoglobulin G (NMO‐IgG) auto‐antibodies to the water channel aquaporin‐4 (AQP4) in astrocytes. To find potential NMO therapeutics, a screening system was established and used to identify inhibitors of NMO‐IgG‐mediated complement‐dependent cytotoxicity (CDC). The screening of approximately 400 compounds yielded potent hit compounds with inhibitory effects against CDC in U87‐MG cells expressing human AQP4. Derivatives of the hit compounds were synthesized and evaluated for their inhibition of CDC. Of the small molecules synthesized, (E)‐1‐(2‐((4‐methoxyphenyl)sulfonyl)vinyl)‐[4‐[(3‐trifluoromethyl)phenyl] methoxy]benzene ( 5 c ) showed the most potent activity in both stably transfected U87‐MG cells and mice‐derived astrocytes. The results of this study suggest that 5 c , which targets NMO‐IgG‐specific CDC, may be useful as a research tool and a potential candidate for therapeutic development for the treatment of NMO. 相似文献
994.
Al2O3–SiC composites containing up to 30 wt.% of dispersed SiC particles (280 nm) were fabricated via hot-pressing and machined as cutting tools. The Al2O3–SiC particulate composites exhibit higher hardness than their unreinforced matrix because of the inhibited grain growth by adding SiC and the presence of hard secondary phase (SiC). The fracture toughness of the composites remains constant up to 10 wt.% loading of SiC. For machining heat-treated AISI 4144140 steel, the Al2O3–10 wt.% SiC composite tool showed the longest tool life, seven times longer than a commercial tool made of Al2O3–TiC composite, while the composite tool with 5 wt.% SiC showed the longest tool life for machining gray cast iron. The improved performance of the Al2O3–SiC composite tools attributes to the transformation of fracture mode from intergranular fracture for Al2O3 to intragranular fracture for Al2O3–SiC composites. 相似文献
995.
Ho-Seong Nam Kwang-Suk Jang Jang Myoun Ko Young-Min Kong Jong-Duk Kim 《Electrochimica acta》2011,(18):3370
The nanoporous RuO2·3.38H2O was synthesized with a surfactant template using sodium dodecyl sulfate. The surface area of the material amounted to 220 m2 g−1 while the maximum specific capacitance obtained was 870 Fg−1 at a scan rate of 10 mV s−1. The specific capacitance of nanoporous RuO2·3.38H2O electrode exhibits enhancement, compared with other porous RuO2 materials synthesized by different methods. The nanoporous RuO2·3.38H2O is a very promising material for high performance capacitance. 相似文献
996.
In-Jin Shon In-Yong Ko Hyun-Su Kang Kyung-Tae Hong Jung-Mann Doh Jin-Kook Yoon 《Ceramics International》2011,37(7):2159-2164
The rapid sintering of nanostructured Al2O3 and Al2O3 to Al2SiO5 composites was investigated by a high-frequency induction heating sintering process. The advantage of this process is that it allows very quick densification to near theoretical density and inhibition of grain growth. Highly dense nanostructured Al2O3 and Al2O3 to Al2SiO5 composites were produced with simultaneous application of a 80 MPa pressure and induced output current of a total power capacity (15 kW) within 3 min. The sintering behavior, grain size and mechanical properties of Al2O3 and Al2O3 to Al2SiO5 composites were investigated. 相似文献
997.
Most process changes and modifications, which are caused by the process failure, the process life cycle and the economic environment, have been generated at industrial facilities. However, management of change (MOC) is based on basic process safety, such as change judgment, risk check with accurate technical references and risk assessment, and is difficult to carry out because of the lack of experience, knowledge, and process safety specialists. In this study, the MOC system was developed based on process safety technology and the drawing information system (DIS) oriented method. This study recommends the MOC system to industrial facilities as the setup of the obvious standard for the decision-making process, the MOC procedure based risk assessment, and the judgment and risk estimation of the process modification. The HIT and CAT modules were developed using the risk assessment checklist, HAZOP risk ranking, scenarios for consequence analysis and reporting automation. These two modules provide a clearcut view on the process risk. An effective risk-based MOC Review was performed by this new method. Additionally, this study suggests a new method for the MOC S/W system. This method was developed using a new technique which was based on the DIS system linking MOC system and the HIT and CAT Modules, including the process safety information. The goals of this method are to enhance the safety level and improve the performance efficiency. 相似文献
998.
999.
Chia-Lung Tsai Feng-Ming Lee Fu-Yi Cheng Meng-Chyi Wu Sum-Chien Ko Hai-Lin Wang Wen-Jeng Ho 《Electron Device Letters, IEEE》2005,26(5):304-307
In this letter, we report on an alternative method to fabricate a high-efficiency planar-type oxide-confined 850-nm vertical-cavity surface-emitting lasers (VCSELs). The planarized process of VCSELs was to use the silicon oxide as the buried layer. As a result, these devices with an oxidized aperture of 3 /spl mu/m in diameter exhibit a single-transverse mode behavior throughout the operation current range. In addition, the static characteristics of VCSELs at 300 K include a threshold current of 0.52mA corresponding to a threshold voltage of 2.2 V, a maximum single transverse-mode light output power of 1.13 mW at 4.5 mA, and an external differential quantum efficiency of 35%. On the other hand, this TO-packaged planar-type 850-nm VCSEL for back-to-back test shows a wide open along with symmetric eye diagram and could also pass the 10 Gb/s mask as operating at 10.3 Gb/s and 4 mA. Furthermore, the VCSEL can still keep the eye diagram open and symmetric after the 66-m multi-mode fiber transmission and has a power penalty of 6.6 dB because of fiber dispersion for 10.3 Gb/s data rate at a bit error rate of 10/sup -11/. These results confirm the excellent high-speed performance of SiO/sub x/-planarized VCSELs as compared to the polyimide-planarized VCSELs. 相似文献
1000.
The virtual distortion method—a versatile reanalysis tool for structures and systems 总被引:4,自引:3,他引:1
Przemysław Kołakowski Marcin Wikło Jan Holnicki-Szulc 《Structural and Multidisciplinary Optimization》2008,36(3):217-234
For 20 years of development, the virtual distortion method (VDM) has proved to be a versatile reanalysis tool in various applications,
including structures and truss-like systems. This article presents a summary of principal achievements, demonstrating the
capabilities of the VDM both in statics and dynamics, in linear and nonlinear analysis. The major advantage of VDM is its
exactness and no need for matrix inversion in the reanalysis algorithm. The influence matrix—numerical core of the VDM—contains
the whole mechanical knowledge about a structure, by looking at all global responses due to local disturbances. The strength
of the method is demonstrated for truss structures. 相似文献