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41.
42.
Hye-Ju Jung Ji-Sook Hong Jeong-Kwon Suh 《Korean Journal of Chemical Engineering》2011,28(9):1882-1888
This study aimed to find a way to remove organic pollutants, phenol and humic acid in aqueous solutions using TiO2 spherical activated carbon (Ti-SPAC). The Ti-SPAC was manufactured by resin ion-exchange and a heating process. This method was very effective not only in creating TiO2 on the surface of the supports evenly, but also in making activated carbon that has highly-developed micro pores. To estimate whether Ti-SPAC has the proper features as a photocatalyst and adsorbent, it was examined in detail by X-ray patterns, SEM image, EDXS, BET, EPMA. The results proved that Ti-SPAC is a very useful material for treating wastewater by photocatalysis and absorption. 相似文献
43.
Suh K.S. Hyung Jae Lee Dai Soo Lee Chang Gyun Kang 《Dielectrics and Electrical Insulation, IEEE Transactions on》1995,2(3):460-466
The formation of space charge in polycarbonate (PC)/poly (styrene-co-acrylonitrile) (SAN) blends containing poly (ϵ-caprolactone) (PCL) as a compatibilizer for improving the miscibility, has been studied by measuring spatial charge distributions. It is found that the miscibility of PC/SAN blends is improved as the PCL content increases. The amount of charge accumulated in the blends decreases when the PCL content increases to 15% by weight and then increases when the PCL content is >15% wt. The decrease of charge at the PCL content <15% wt was attributed to the combined effects of changes in conductivities and the molecular interactions at the domain interfaces. The increase of charge at the PCL content >15% wt was attributed to the trapping of charge at the amorphous and crystalline phases of PC and PCL 相似文献
44.
New type of amphiphilic pH-sensitive polyurethane networks, derived from the mixture of polyethylene glycol-modified urethane
acrylates (PMUA) and urethane acrylate anionomer (UAA), were prepared and their swelling behaviors were evaluated. Three kinds
of polymerization methods were employed in the synthesis of polyurethane networks. Polyurethane networks prepared by a process
similar to that of soap-free emulsion polymerization (UAHG) showed the highest swelling ratio and pH-sensitivity. Additionally,
four kinds of UAHG gels were prepared at different composition of UAA. As the composition ratio of UAA to PMUA increased,
swelling of UAHG gels in alkali pH buffer solution and their pH-sensitivity greatly increased. Additionally, swelling of UAHG
gels changed reversibly with the change of pH.
Received: 18 November 1996/Revised: 10 January 1997/Accepted: 14 January 1997 相似文献
45.
46.
Polyurethane acrylate anionomer (PUAA)/silica composite gels were prepared by the sol‐gel reaction of tetraethoxysilane (TEOS) and methacryloxypropyl trimethoxysilane (MPTS) incorporated to PUAA gels by using a swelling method. The formation and structure of composites were confirmed by FTIR, X‐ray diffraction, and SEM. As a result, we found that silica components in composites are located within the ionic domains of their gels and interacted with PUAA via hydrogen bonding. This drastically enhanced the mechanical properties of the composites. Mechanical properties are also improved by MPTS, because MPTS improves the dispersibility and adhesion of silica components in PUAA/silica composite gels. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2327–2334, 2002 相似文献
47.
Multifunctional monomers, m‐xylylenedimaleimide, p‐phenylenedimaleimide, m‐phenylenedimaleimide, and p‐phenylenedinadimide, all of which have maleimide groups, were synthesized to increase thermal and radiation stabilities. The synthesized multifunctional monomers showed good compatibility with low‐density polyethylene (LDPE). Mixtures of LDPE and these multifunctional monomers were irradiated with γ‐rays from a Co‐60 source at room temperature in a nitrogen atmosphere. The absorbed dose ranged from 0 to 160 KGy. Among these multifunctional monomers, m‐xylylenedimaleimide was the best in gel fraction enhancement. Crosslinked LDPE with m‐xylylenedimaleimide displayed a higher modulus than that of crosslinked LDPE with triallyl cyanurate. For the elongation property, LDPE with m‐xylylenedimaleimide as a multifunctional monomer showed better results than that with commercial multifunctional monomers such as triallyl cyanurate (TAC) and trimethylol propane triacrylate (TMPTA). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2339–2345, 2003 相似文献
48.
A new anionic conjugated polymer containing a fluorene group in the main chain was designed and synthesized from poly(2,7‐(9,9′‐dihexylfluorene)‐5,5′‐bibenzimidazole) (PFBI). The polymer showed strong blue emission with high quantum efficiency (0.64) at 450 nm in MeOH and the dramatic quenching effect by Methyl Viologen (MV2+). The fluorescence‐quenching effect results from the weak complex formation between an anionic polymer and electron acceptors such as bipyridinium derivatives. The linear Stern–Volmer constant (Ksv) was 3.7×105 M?1 for MV2+. The newly synthesized polymer is expected to show the applicability for biological and chemical sensors. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 900–904, 2004 相似文献
49.
Injection molding is one of the most commonly used methods of processing polymers. The process allows rapid, automated production of a wide variety of complicated, three-dimensional parts in large production volumes. The process is capable of producing compound curvatures, snaps, hinges, bosses, threaded holes, gear teeth, and many other features. With proper design, these complex parts can be produced in a single molding operation. 相似文献
50.
Bongjune Kim Jaemoon Yang Myeonghwan Hwang Jihye Choi Hyun-Ouk Kim Eunji Jang Jung Hwan Lee Sung-Ho Ryu Jin-Suck Suh Yong-Min Huh Seungjoo Haam 《Nanoscale research letters》2013,8(1):399
Nucleic acid-based aptamers have been developed for the specific delivery of diagnostic nanoprobes. Here, we introduce a new class of smart imaging nanoprobe, which is based on hybridization of a magnetic nanocrystal with a specific aptamer for specific detection of the angiogenic vasculature of glioblastoma via magnetic resonance (MR) imaging. The magnetic nanocrystal imaging core was synthesized using the thermal decomposition method and enveloped by carboxyl polysorbate 80 for water solubilization and conjugation of the targeting moiety. Subsequently, the surface of the carboxylated magnetic nanocrystal was modified with amine-functionalized aptamers that specifically bind to the vascular growth factor receptor 2 (VEGFR2) that is overexpressed on angiogenic vessels. To assess the targeted imaging potential of the aptamer-conjugated magnetic nanocrystal for VEGFR2 markers, the magnetic properties and MR imaging sensitivity were investigated using the orthotopic glioblastoma mouse model. In in vivo tests, the aptamer-conjugated magnetic nanocrystal effectively targeted VEGFR2 and demonstrated excellent MR imaging sensitivity with no cytotoxicity. 相似文献