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991.
Jooyoung Chung Jihyun Myoung Jisook Oh Sangwoo Lim 《Journal of Physics and Chemistry of Solids》2012,73(4):535-539
Thin ZnSe layers were deposited on ZnO nanowires by a novel successive ionic layer adsorption and reaction technique in order to solve recombination problems in ZnO nanowire-based dye-sensitized solar cells (DSSCs). Cell efficiency increased from 0.1 to 1.3–1.4% with the deposition of a 9- to13-nm-thick ZnSe shell on ZnO nanowires due to a large increase in JSC. The dramatic increase in JSC and cell efficiency is due to the facilitation of electron transfer related to ambipolar diffusion by the formation of a type II band alignment and the suppression of recombination in the presence of the ZnSe shell. 相似文献
992.
Dong Kyu Lim Nguyen Phuoc Long Sanghan Choo Changyeun Mo Ziyuan Dong Giyoung Kim 《Analytical letters》2017,50(16):2519-2529
Milling is an influential factor that affects the nutritional components in rice. However, the alteration of rice constituents by milling has not been thoroughly examined. In this study, rice with various degrees of milling was analyzed by gas chromatography–mass spectrometry and high-performance liquid chromatography–mass spectrometry. Principal component analysis and partial least square-discriminant analysis were performed to characterize the nutritional components that have significant changes during milling. The concentrations of sugars and sugar alcohols decreased while the phospholipids increased in accordance with the milling degree. These results provide a contrast to the common idea that brown rice is nutritionally superior to white rice. In conclusion, the knowledge of nutritional alterations related to milling may benefit rice production and consumption. 相似文献
993.
994.
995.
Hae Lim Kim Hae Jin Lee Dong-Ryung Lee Bong-Keun Choi Seung Hwan Yang 《Molecules (Basel, Switzerland)》2020,25(22)
The aim of this study was to determine the anti-osteoarthritic effects of LI73014F2, which consists of Terminalia chebula fruit, Curcuma longa rhizome, and Boswellia serrata gum resin in a 2:1:2 ratio, in the monosodium iodoacetate (MIA)-induced osteoarthritis (OA) rat model. LI73014F2 was orally administered once per day for three weeks. Weight-bearing distribution and arthritis index (AI) were measured once per week to confirm the OA symptoms. Synovial membrane, proteoglycan layer, and cartilage damage were investigated by histological examination, while synovial fluid interleukin-1β level was analyzed using a commercial kit. Levels of pro-inflammatory mediators/cytokines and matrix metalloproteinases (MMPs) in the cartilage tissues were investigated to confirm the anti-osteoarthritic effects of LI73014F2. LI73014F2 significantly inhibited the MIA-induced increase in OA symptoms, synovial fluid cytokine, cartilage damage, and expression levels of pro-inflammatory mediators/cytokines and MMPs in the articular cartilage. These results suggest that LI73014F2 exerts anti-osteoarthritic effects by regulating inflammatory cytokines and MMPs in MIA-induced OA rats. 相似文献
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997.
We study a new asymptotic invariant of a pair consisting of a group and a subgroup, which we call the commensurator growth.
We compute the commensurator growth for several examples, concentrating mainly on the case of a locally compact topological group and a lattice inside it. 相似文献
998.
Venu Gopal Bairi Jin-Hee Lim Andrew Fong Sean W. Linder 《Journal of nanoparticle research》2017,19(7):256
There is an increase in the usage of engineered metal oxide (TiO2 and ZnO) nanoparticles in commercial sunscreens due to their pleasing esthetics and greater sun protection efficiency. A number of studies have been done concerning the safety of nanoparticles in sunscreen products. In order to do the safety assessment, it is pertinent to develop novel analytical techniques to analyze these nanoparticles in commercial sunscreens. This study is focused on developing analytical techniques that can efficiently determine particle size of metal oxides present in the commercial sunscreens. To isolate the mineral UV filters from the organic matrices, specific procedures such as solvent extraction were identified. In addition, several solvents (hexane, chloroform, dichloromethane, and tetrahydrofuran) have been investigated. The solvent extraction using tetrahydrofuran worked well for all the samples investigated. The isolated nanoparticles were characterized by using several different techniques such as transmission electron microscopy, scanning electron microscopy, dynamic light scattering, differential centrifugal sedimentation, and x-ray diffraction. Elemental analysis mapping studies were performed to obtain individual chemical and morphological identities of the nanoparticles. Results from the electron microscopy techniques were compared against the bulk particle sizing techniques. All of the sunscreen products tested in this study were found to contain nanosized (≤100 nm) metal oxide particles with varied shapes and aspect ratios, and four among the 11 products were showed to have anatase TiO2. 相似文献
999.
Preparation of microporous polymers in the form of particles and a thin film from hyperbranched polyphenylenes
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Min Chul Cha Yoonbin Lim Ji Young Chang 《Journal of polymer science. Part A, Polymer chemistry》2015,53(20):2336-2342
The use of a hyperbranched polymer as a building block for the synthesis of a microporous organic polymer was demonstrated. Hyperbranched polyphenylenes (HBPs) were prepared from (3,5‐dibromophenyl)boronic acid, which contained numerous unreacted bromophenyl end groups. Utilizing metal‐catalyzed coupling reactions between these functional groups, cross‐linked porous polymers were obtained. Although the HBPs did not show porosity, their cross‐linked polymers had highly porous structures with Brunauer–Emmett–Teller surface areas of up to 2030 m2/g. An insoluble porous thin film was fabricated by spin casting of a solution containing a HBP followed by Sonogashira cross‐coupling reaction. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2336–2342 相似文献
1000.
Ho Doris M. L. Nelwamondo Aubrey N. Okubo Ayako Ramebäck Henrik Song Kyuseok Han Sun Ho Hancke Jacobus J. Holmgren Stina Jonsson Sofia Kataoka Osamu Lagerkvist Petra Lee Chi-Gyu Lim Sang Ho Park Jinkyu Park Jong-Ho Pong Boon Kin Sandström Björn Shinohara Nobuo Tan Angela H. J. Toda Nobufumi Tovedal Annika Vesterlund Anna 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(2):353-363
Journal of Radioanalytical and Nuclear Chemistry - The Fourth Collaborative Material Exercise (CMX-4) of the Nuclear Forensics International Technical Working Group (ITWG) registered the largest... 相似文献