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71.
Han‐Shiang Huag Shiu‐Huey Chou Trong‐Ming Don Wei‐Chi Lai Liao‐Ping Cheng 《先进技术聚合物》2009,20(12):1082-1090
Microporous membranes of a biodegradable polymer, poly(hydroxybutyric acid) (PHB), were prepared by a phase‐inversion process and their cell compatibility was evaluated in vitro. A ternary system, ethanol/chloroform/PHB, was employed to prepare the membranes, wherein ethanol and chloroform were served as the nonsolvent and solvent for PHB, respectively. In the phase‐inversion process, the polymer dissolution temperature was varied from 80 to 120°C to yield membranes with specific morphologies, such as globular particles, porous channels, etc. Moreover, cell viability was examined on the formed membranes. Two cell lines, osteoblast hFOB1.19 and fibroblast L929, were cultured in vitro. It was found that these two types of cells exhibited different responses on different membranes: the hFOB1.19 cells showed significant increase in cell proliferation with increase in surface roughness, whereas the L929 cells demonstrated an opposite trend, preferring to attach and grow on a flat surface. PHB membranes with different morphologies exhibit different cell compatibilities, which may be useful means for the architectural design of materials for tissue engineering. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
72.
Barklow T Abrams GS Adolphsen CE Averill D Ballam J Barish BC Barnett BA Bartelt J Bethke S Blockus D Bonvicini G Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan DE Dorfan JM Drewer DC Elia R Feldman GJ Fernandes D Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gatto C Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Grindhammer G Grosse-Wiesmann P Hanson G Harr R Harral B Harris FA 《Physical review letters》1990,64(25):2984-2987
73.
Prof. Xi-Lin Wu Shiang Liu Yu Li Minjia Yan Prof. Hongjun Lin Prof. Jianrong Chen Prof. Shoujie Liu Prof. Shaobin Wang Dr. Xiaoguang Duan 《Angewandte Chemie (International ed. in English)》2023,62(30):e202305639
In photosynthesis, solar energy is harvested by photosensitizers, and then, the excited electrons transfer via a Z-Scheme mode to enzymatic catalytic centers to trigger redox reactions. Herein, we constructed a core–shell Z-scheme heterojunction of semiconductor@single-atom catalysts (SACs). The oxygen-vacancy-rich ZnO core and single-atom Co−N4 sites supported on nitrogen-rich carbon shell (SA-Co-CN) act as the photosensitizer and the enzyme-mimicking active centers, respectively. Driven by built-in electric field across the heterojunction, photoexcited electrons could rapidly (2 ps) transfer from the n-type ZnO core to the p-type SA-Co-CN shell, finally boosting the catalytic performance of the surface-exposed single-atom Co−N4 sites for peroxymonosulfate (PMS) activation under light irradiation. The synergies between photocatalysis and heterogeneous Fenton-like reaction lead to phenomenally enhanced production of various reactive oxygen species for rapid degradation of various microcontaminants in water. Experimental and theoretical results validate that the interfacial coupling of SA-Co-CN with ZnO greatly facilitates PMS adsorption and activation by reducing the adsorption energy and enhancing the cascade electron transfer processes for the photo-Fenton-like reaction. 相似文献
74.
Sheng‐Hsiung Yang Shiang‐Ying Chen Yu‐Chun Wu Chain‐Shu Hsu 《Journal of polymer science. Part A, Polymer chemistry》2007,45(15):3440-3450
A new series of poly(2,3‐diphenyl‐1,4‐phenylenevinylene) derivatives containing dendritic side groups were synthesized. Different generations of dendrons were integrated on the pendant phenyl ring to investigate their effect on optical and electrical properties of final polymers. Homopolymers can not be obtained via the Gilch polymerization because of sterically bulky dendrons. By controlling the feed ratio of different monomers during polymerization, dendron‐containing copolymers with high molecular weights were obtained. The UV–vis absorption and photoluminescent spectra of the thin films are pretty close; however, quantum efficiency is significantly enhanced with increasing the generation of dendrons. The electrochemical analysis reveals that hole‐injection is also improved by increasing dendritic generation. Double‐layer light‐emitting devices with the configuration of ITO/PEDOT:PSS/polymer/Ca/Al were fabricated. High generation dendrons bring benefit of improved device performance. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3440–3450, 2007 相似文献
75.
Chung‐Han Yu Min‐Shiang Kuo Ching‐Yi Chuang Gene‐Hsiang Lee Shao‐An Hua Prof. Bih‐Yaw Jin Prof. Dr. Shie‐Ming Peng 《化学:亚洲杂志》2014,9(11):3111-3115
Chirality control of helixes with the Δ (P) or Λ (M) form is interesting in various fields such as extended metal atom chains (EMACs), in which the metal backbones are helically wrapped by four ligands. Herein, we report two EMACs, Δ‐[Ni5((?)camnpda)4] and Λ‐[Ni5((+)camnpda)4], whose chiralities are controlled by chiral ligands with naphthyridine and camphorsulfonyl groups. There is a large energy difference (108 kcal mol?1) between the two helical structures with one chiral ligand. Furthermore, the electron communication between [Ni2]3+ units is more pronounced than in [Ni5(bna)4Cl2]2+ (bna=binaphthyridylamido). The results demonstrate control of small‐scale helical structure and set the stage for future development of chiral controlled base and nanoelectronic devices. 相似文献
76.
This study examined the conceptions of nature of science (NOS) possessed by a group of gifted seventh‐grade students from Taiwan. The students were engaged in a 1‐week science camp with emphasis on scientific inquiry and NOS. A Chinese version of a NOS questionnaire was developed, specifically addressing the context of Chinese culture, to assess students' views on the development of scientific knowledge. Pretest results indicated that the majority of participants had a basic understanding of the tentative, subjective, empirical, and socially and culturally embedded aspects of NOS. Some conflicting views and misconceptions held by the participants are discussed. There were no significant changes in students' views of NOS after instruction, possibly due to time limitations and a ceiling effect. The relationship between students' cultural values and development of NOS conceptions and the impact of NOS knowledge on students' science learning are worth further investigation. 相似文献
77.
A series of N‐aryl 2‐alkenamides were produced efficiently by treating N‐aryl 3‐(phenylsulfonyl)‐propanamides with potassium tert‐butoxide in THF at 0°C. With out isolation, it was further treated with an additional equivalent of potassium tert‐butoxide and allyl bromide to give N‐allyl N‐aryl 2‐alkenamides in one pot in good yields. Followed by a ring‐closing metathesis reaction, these N‐allyl N‐aryl 2‐alkenamides were respectively converted into corresponding N‐aryl α,β‐unsaturated γ‐lactams in moderate yields. 相似文献
78.
Bobeldijk I Bouwhuis M Ireland DG de Jager CW Jans E de Jonge N Kasdorp WJ Konijn J Lapikás L van Leeuwe JJ van der Meer RL Nooren GJ Passchier E Schroevers M van der Steenhoven G Steijger JJ Theunissen JA van Uden MA de Vries H de Vries R de Witt Huberts PK Blok HP van den Brink HB Dodge GE Harakeh MN Hesselink WH Kalantar-Nayestanaki N Pellegrino A Spaltro CM Templon JA Hicks RS Kelly JJ Marchand C 《Physical review letters》1994,73(20):2684-2687
79.
Chih‐Ching Huang Prof. Yu‐Lun Hung Yen‐Chun Shiang Tai‐Yuan Lin Prof. Yu‐Shen Lin Chao‐Tsen Chen Prof. Huan‐Tsung Chang Prof. 《化学:亚洲杂志》2010,5(2):334-341
We have employed mannose‐modified gold nanodots (Man–Au NDs) as a luminescence sensor for the detection of the thyroid‐cancer marker thyroglobulin (Tg) in homogeneous solutions. The luminescent Man–Au NDs are prepared through the reaction of 2.9 nm‐diameter gold nanoparticles (Au NPs) with 11‐mercapto‐3,6,9‐trioxaundecyl‐α‐D ‐mannopyranoside (Man‐RSH) under the irradiation of a light‐emitting diode (LED). We have found that the irradiation enhances the quantum yield (~11 %), alters the emission wavelength and lifetimes, and shortens the preparation time. A luminescence assay has been developed for Tg based on the competition between Tg and Man–Au NDs for the interaction with the concanavalin A (Con A). Because luminescence quenching of the Man–Au NDs by Con A is inhibited by Tg selectivity, we have obtained a highly sensitive and selective assay for Tg. 相似文献
80.
Keh-Dong Shiang 《Physics letters. A》1993,180(6):444-452
We propose in this paper a theoretical model to investigate surface self-diffusion of single adatoms on two different low-index planes, closely packed (001) and densely packed (111), of face-centered-cubic rhodium, nickel and copper metal crystals. Two realistic model potentials are applied to describe the interatomic interaction of the adatom-substrate systems. The first model is a Morse-type potential, which involves several empirical fittings of bulk of solid. The second, newly popular, potential was introduced by Sutton and Che, which incorporates many-body effects. With these potentials, conventional molecular dynamics (MD) is employed to obtain trajectories of the atoms. The average squared didplacements are computed for a range of initial kinetic energies, and the surface diffusion constants can be obtained by means of the Einstein relation. The estimated random walk exponential prefactors and activation energies exhibit an Arrhenius behavior, and are compared with previous results. 相似文献