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Coordination Polymer Nanobamboos of {FexIn1−x}‐MIL‐88B: Induced Formation of a Virtual In‐MIL‐88B 下载免费PDF全文
Shin Ae Park Hee Jung Lee Yea Jin Cho Sora Choi Prof. Moonhyun Oh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(19):5559-5564
A precise fabrication of nanobamboo structures made from hybrid coordination polymers of the type {FexIn1?x}‐MIL‐88B is demonstrated. The compositions of the hybrid coordination polymer nanobamboos of {FexIn1?x}‐MIL‐88B (x=0.06, 0.19, or 0.75) are regulated by altering the amount of metal ions used in the reactions. Interestingly, the formation of a virtual In‐MIL‐88B (precise structure, {Fe0.06In0.94}‐MIL‐88B), which cannot be created in a typical reaction, is induced by the assistance of a Fe‐MIL‐88B structure. The a and c cell parameters of {Fe0.06In0.94}‐MIL‐88B are calculated at 10.95 and 19.86 Å, respectively. These values of {Fe0.06In0.94}‐MIL‐88B are larger than those of pure Fe‐MIL‐88B owing to the large ionic size of In3+ within the framework. 相似文献
43.
Daria A. Chernova Andrey KH. Vorobiev 《Journal of Polymer Science.Polymer Physics》2009,47(1):107-120
ESR spectra of three spin probes with different molecular volumes: 2,2,6,6‐tetramethyl‐4‐oxopiperidine‐1‐oxyl, di‐p‐anisylnitroxide, and nitroxide derivative of fullerene in glassy polystyrene, polyvinyl trimethylsilane, and Teflon AF‐2400 were calculated numerically within the model of quasi‐libration motions. Temperature ranges, where the model is capable to reproduce spectra within experimental errors, were defined. It was found that simulation of X‐band ESR spectra allows to determine quasi‐libration amplitudes around molecular axes X and Y with accuracy ~ 3° and around Z axis with accuracy ~ 15–20°. A shape of distribution of quasi‐libration amplitudes was also determined qualitatively by ESR spectra simulations. It was established that the average amplitude of quasi‐libration motion depends on the free volume of each polymer and geometrical molecular volume of a spin probe. Quasi‐libration amplitudes increase as the temperature increases, and reach the value of 40 degrees. We found that upon further temperature increase, quasi‐libration model becomes inapplicable for quantitative numerical spectra simulation. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 107–120, 2009 相似文献
44.
A phytotoxic compound, identified as 2-(2-acetyl-3,5-dihydroxyphenyl) acetic acid (curvulinic acid), was isolated from liquid cultures of the phytopathogenic fungus Nimbya alternantherae. The activity of curvulinic acid on seed germination and seedling growth of Capsella bursa-pastoris was evaluated. Percentage seed germination of C. bursa-pastoris was decreased with increasing concentrations of curvulinic acid. The compound had stronger inhibitory effects on root length than shoot length. At a concentration of 600 microg x mL(-1), curvulinic acid caused 73.5% and 66.7% growth inhibition on roots and shoots with IC50 values of 204.7 and 281.1 microg x mL(-1), respectively. The finding of curvulinic acid in N. alternantherae and its herbicidal activity are reported here for the first time. 相似文献
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Yi Quan Liua Hui Hui Li Yun Hua Yea Gu Yuan a Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry Molecular Engineering of Ministry of Education 《中国化学快报》2009,20(3)
The interaction between HIV-I DNA and five cyclic peptides (CPI-CP5) was investigated using electrospray ionization mass spectrometry (ESI-MS). It revealed that CPI [c(Ala-Tyr-Leu-Ala-Gly)] and CP4 [c(Pro-D-Tyr-Leu-D-Ala-Gly)] have the higher binding affinity with the duplex DNA among the five cyclic peptides. 相似文献
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UV LASER INDUCED RNA-PROTEIN CROSSLINKS AND RNA CHAIN BREAKS IN TOBACCO MOSAIC VIRUS RNA in situ 总被引:2,自引:0,他引:2
E. N. DOBROV Z. KH. ARBIEVA E. K. TIMOFEEVA R. O. ESENALIEV A. A. ORAEVSKY D. N. NIKOGOSYAN 《Photochemistry and photobiology》1989,49(5):595-598
The efficiency of RNA-protein crosslink and RNA chain break formation under nanosecond or picosecond UV-laser pulse irradiation of tobacco mosaic virus was determined. It was found that on high-intensity UV-laser irradiation the quantum yields of both reactions increase considerably as compared to the usual (low-intensity) UV-irradiation. The RNA-protein crosslink quantum yield was found to be 1.8 x 10(-5) and 1.2 x 10(-4) and that of RNA chain breaks 1.7 x 10(-4) and 8.9 x 10(-4) for nanosecond and picosecond irradiation, respectively. 相似文献
49.
Yossra A. Trabik Nourhan KH. Al-Afify Amira M. El-Kosasy N. Magdy 《Electroanalysis》2021,33(5):1233-1243
Chitosan (CH) is one of the most abundant biopolymers with multiple applications. Polyvinyl pyrrolidone (PVP) has specific binding and detoxification properties that are of great interest in health care. Hence, it arises a crucial urge to develop economic sensors to analyze CH and PVP in pharmaceutical formulations and biological samples. Two portable sensors were fabricated using precipitation-based technique, and nanoparticles-based technique, for determination of CH and PVP in sensor 1 and 2; respectively. Linear responses of 10−5 to10−7 M and 10−2 to10−7 M at pH 3.6–4.8 and 7.2–8.4, with ideal Nernstian slopes of 60.00 and 59.83 mV /decade, and nanomolar LODs of 94.90 and 81.20 nM were observed for CH and PVP; respectively. The percentage recoveries were 100.40±1.03 and 100.19±0.64 for sensors 1 and 2; respectively. Both sensors were successfully applied in biological fluids without pre-treatment. Accurate results were obtained using sensor 1, in pure form, pharmaceutical formulations, human plasma, rat liver and rat brain, as well as sensor 2, in pure form, pharmaceutical formulations and urine samples. The results were statistically compared with the reported methods and no significant difference was observed. 相似文献
50.