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81.
Hyeohn Kim Sang Won Im Nam Heon Cho Da Hye Seo Ryeong Myeong Kim Yae‐Chan Lim Hye‐Eun Lee Hyo‐Yong Ahn Ki Tae Nam 《Angewandte Chemie (International ed. in English)》2020,59(31):12976-12983
Chiral optical metamaterials with delicate structures are in high demand in various fields because of their strong light–matter interactions. Recently, a scalable strategy for the synthesis of chiral plasmonic nanoparticles (NPs) using amino acids and peptides has been reported. Reported herein, 3D chiral gold NPs were synthesized using dipeptide γ‐Glu‐Cys and Cys‐Gly and analyzed crystallographically. The γ‐Glu‐Cys‐directed NPs present a cube‐like outline with a protruding chiral wing. In comparison, the NPs synthesized with Cys‐Gly exhibited a rhombic dodecahedron‐like outline with curved edges and elliptical cavities on each face. Morphology analysis of intermediates indicated that γ‐Glu‐Cys generated an intermediate concave hexoctahedron morphology, while Cys‐Gly formed a concave rhombic dodecahedron. NPs synthesized with Cys‐Gly are named 432 helicoid V because of their unique morphology and growth pathway. 相似文献
82.
Wooseup Hwang Jejoong Yoo In‐Chul Hwang Jiyeon Lee Young Ho Ko Hyun Woo Kim Younghoon Kim Yeonsang Lee Moon Young Hur Kyeng Min Park Jongcheol Seo Kangkyun Baek Kimoon Kim 《Angewandte Chemie (International ed. in English)》2020,59(9):3460-3464
Hierarchical self‐assembly of building blocks over multiple length scales is ubiquitous in living organisms. Microtubules are one of the principal cellular components formed by hierarchical self‐assembly of nanometer‐sized tubulin heterodimers into protofilaments, which then associate to form micron‐length‐scale, multi‐stranded tubes. This peculiar biological process is now mimicked with a fully synthetic molecule, which forms a 1:1 host‐guest complex with cucurbit[7]uril as a globular building block, and then polymerizes into linear poly‐pseudorotaxanes that associate laterally with each other in a self‐shape‐complementary manner to form a tubular structure with a length over tens of micrometers. Molecular dynamic simulations suggest that the tubular assembly consists of eight poly‐pseudorotaxanes that wind together to form a 4.5 nm wide multi‐stranded tubule. 相似文献
83.
Yong-Hee Park Jungwon Kim Hyoungjoon Kim Ilsoo Kim Ki-Young Lee Dongjea Seo Heon-Jin Choi Woochul Kim 《Applied Physics A: Materials Science & Processing》2011,104(1):7-14
In this paper, we synthesize VLS-grown rough Si nanowires using Mn as a catalyst with various surface roughnesses and diameters
and measured their thermal conductivities. We grew the nanowires by a combination vapor-liquid-solid and vapor-solid mechanism
for longitudinal and radial growth, respectively. The surface roughness was controlled from smooth up to about 37 nm by the
radial growth. Our measurements showed that the thermal conductivity of rough surface Si nanowires is significantly lower
than that of smooth surface nanowires and decreased with increasing surface roughness even though the diameter of the smooth
nanowire was lower than that of the rough nanowires. Considering both nanowires were grown via the same growth mechanism,
these outcomes clearly demonstrate that the rough surface induces phonon scattering and reduces thermal conductivity with
this nanoscale-hole-free nanowires. Control of roughness induced phonon scattering in Si nanowires holds promise for novel
thermoelectric devices with high figures of merit. 相似文献
84.
We correct some statements in the paper mentioned in the title. 相似文献
85.
Hyun Ook Seo Myung‐Geun Jeong Kwang‐Dae Kim Dae Han Kim Young Dok Kim Dong Chan Lim 《Surface and interface analysis : SIA》2014,46(8):544-549
Degradation behaviors of poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) layers on NiO in the presence of H2O at ambient pressure and dark conditions were studied using X‐ray photoelectron spectroscopy (XPS). Upon H2O exposure at 120 °C, partial oxidation of P3HT together with molecular water incorporation, but with the maintained local ring‐structure, were deduced by XPS. Valence band spectra of XPS evidenced that the partial oxidation of P3HT local structure could alter π‐conjugation systems of P3HT layers, forming additional electronic states close to its original highest occupied molecular orbital. For comparison, P3HT surface was also exposed to O2, and no change in the S 2p and C 1s spectra was found by O2 exposure at 120 °C, implying that H2O plays a major role at the initial stage of P3HT oxidation. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
86.
Electrophoresis 2014, 35, 1504–1508. DOI: 10.1002/elps.201400001 Combination of DNA biobarcode assay with micro‐capillary electrophoretic analysis on a chip allows us to perform breast and colorectal cancer cell detection with high sensitivity, multiplexity, and accuracy.
87.
We synthesized a fluorescent adenosine derivative, rApy, as a probe to study RNA structural transitions, in particular the intermolecular G-quadruplex formation. rApy was incorporated into the dangling positions of guanine-rich oligonucleotides, which under physiological conditions undergo π-stacking on top of each other exhibiting a strong emission signal in their G-quadruplex conformation, but not in their single-stranded state. 相似文献
88.
Back Cover: Synthesis,Characterization, Self‐Assembly,Gelation, Morphology and Computational Studies of Alkynylgold(III) Complexes of 2,6‐Bis(benzimidazol‐2′‐yl)pyridine Derivatives (Chem. Eur. J. 32/2014) 下载免费PDF全文
89.
Soo Chool Lee Min Sun Cho Suk Yong Jung Chong Kul Ryu Jae Chang Kim 《Adsorption》2014,20(2-3):331-339
A range of potassium-based alumina sorbents were fabricated by impregnation of alumina with K2CO3 to examine the effects of the structural and textural properties of alumina on the CO2 sorption and regeneration properties. Alumina materials, which were used as supports, were prepared by calcining alumina at various temperatures (300, 600, 950, and 1,200 °C). The CO2 sorption and regeneration properties of these sorbents were examined during multiple tests in a fixed-bed reactor in the presence of 1 vol% CO2 and 9 vol% H2O. The regeneration capacities of the potassium-based alumina sorbents increased with increasing calcination temperature of alumina. The formation of KHCO3 increased with increasing calcination temperature during CO2 sorption, whereas the formation of KAl(CO3)(OH)2, which is an inactive material, decreased. These results is due to the fact that the structure of alumina by the calcination temperature is related directly to the formation of the by-product [KAl(CO3)(OH)2]. The structure of alumina plays an important role in enhancing the regeneration capacity of the potassium-based alumina sorbent. Based on these results, a new potassium-based sorbent using δ-Al2O3 as a support was developed for post-combustion CO2 capture. This sorbent maintained a high CO2 capture capacity of 88 mg CO2/g sorbent after two cycles. In particular, it showed a faster sorption rate than the other potassium-based alumina sorbents examined. 相似文献
90.
Jai Han Seok Mohamed E. El-Khouly Yasuyuki Araki Kwang-Yol Kay 《Journal of organometallic chemistry》2009,694(12):1818-3862
Photoinduced electron transfer processes of two newly synthesized tetrads with a triphenylamine (TPA) as central building block, to which bisfullerenes (C60) and bisferrocenes (Fc) are covalently connected, have been studied. One of them has a TPA linked with one C60 moiety and two ferrocene moieties C60-TPA-(Fc)2 and another tetrad has a TPA linked with two C60 moieties and one ferrocene unit (C60)2-TPA-Fc. The photophysical properties of (C60)m-TPA-(Fc)n have been investigated by applying the picosecond time-resolved fluorescence and nanosecond transient absorption techniques in both polar and nonpolar solvents. The charge separation process via the excited singlet state of the C60 moiety of the C60-TPA-(Fc)2 is more efficient than that of the (C60)2-TPA-Fc. It is found that the ratio of Fc-donor to C60-acceptor affects charge separation efficiency via the excited singlet state of the C60 moiety. 相似文献