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41.
Dr. Katherine G. Young Behnam Najafi William M. Sant Prof. Sonia Contera Prof. Ard A. Louis Prof. Jonathan P. K. Doye Prof. Andrew J. Turberfield Dr. Jonathan Bath 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16076-16080
DNA self-assembly allows the construction of nanometre-scale structures and devices. Structures with thousands of unique components are routinely assembled in good yield. Experimental progress has been rapid, based largely on empirical design rules. Herein, we demonstrate a DNA origami technique designed as a model system with which to explore the mechanism of assembly. The origami fold is controlled through single-stranded loops embedded in a double-stranded DNA template and is programmed by a set of double-stranded linkers that specify pairwise interactions between loop sequences. Assembly is via T-junctions formed by hybridization of single-stranded overhangs on the linkers with the loops. The sequence of loops on the template and the set of interaction rules embodied in the linkers can be reconfigured with ease. We show that a set of just two interaction rules can be used to assemble simple T-junction origami motifs and that assembly can be performed at room temperature. 相似文献
42.
Headspace-solvent microextraction (HS–SME) with sample ultrasound irradiation was successfully used for the study of the influence
of nitrogen fertilization and plant density on the essential oil yield and composition of cumin (Cuminum cyminum L.) seeds. The components were collected into a single microdrop of n-heptadecane and directly injected into a GC–MS injection port for analysis. A simplex method was used for fast optimization
of the extraction parameters. The experiments were executed as split-plot based on randomized complete block design. Nitrogen
fertilization as the main factor (in four levels) and plant density as subsidiary factor (in three levels) were applied. It
was shown that the total GC peak areas of the HS–SME extract, is proportional to the essential oil yield of the cumin seeds
obtained by a hydrodistillation method. Furthermore, similar trends in the concentrations of cuminaldehyde and most other
volatile components were obtained by the two methods. 相似文献
43.
Katherine G. Young Behnam Najafi William M. Sant Sonia Contera Ard A. Louis Jonathan P. K. Doye Andrew J. Turberfield Jonathan Bath 《Angewandte Chemie (International ed. in English)》2020,59(37):15942-15946
DNA self‐assembly allows the construction of nanometre‐scale structures and devices. Structures with thousands of unique components are routinely assembled in good yield. Experimental progress has been rapid, based largely on empirical design rules. Herein, we demonstrate a DNA origami technique designed as a model system with which to explore the mechanism of assembly. The origami fold is controlled through single‐stranded loops embedded in a double‐stranded DNA template and is programmed by a set of double‐stranded linkers that specify pairwise interactions between loop sequences. Assembly is via T‐junctions formed by hybridization of single‐stranded overhangs on the linkers with the loops. The sequence of loops on the template and the set of interaction rules embodied in the linkers can be reconfigured with ease. We show that a set of just two interaction rules can be used to assemble simple T‐junction origami motifs and that assembly can be performed at room temperature. 相似文献
44.
45.
Jasim M. A. Al-Rawi George Q. Behnam Naceur Ayed 《Magnetic resonance in chemistry : MRC》1983,21(1):75-77
Carbon-13 chemical shifts and the POC, POCC, PNC and PNCC coupling constants of 18 compounds containing the amine moiety, and with the general formula Y2P(X)NHR [Y=C2H5O, C6H5O, CH2O, Y2=1,2-dioxybenzene; X = O or S; R = H, CH3, C2H5, PhCH2CH2, (CH3)2CH, C(CH3)3, C6H11, C6H5, C6H5NH] have been determined. The Y2P(X) group shows a sterically induced effect on the amine moiety; the 13C chemical shift of the Y group is, however, almost unaffected on replacing P(O) by a P(S) group. 相似文献
46.
Jasim M. A. Al-Rawi George Q. Behnam Nihad I. Taha 《Magnetic resonance in chemistry : MRC》1981,17(3):204-206
Pyridine, methylpyridines, quinoline and isoquinoline have been labelled with deuterium using pre-reduced platinum dioxide (PtO2·2H2O) and heavy water. Their 2H chemical shifts from monodeuteriated TMS have been assigned. The extent of the labelling has been determined directly by 2H NMR spectroscopy. 相似文献
47.
Nano‐structured gemini‐based supramolecular solvent for the microextraction of cyhalothrin and fenvalerate 下载免费PDF全文
Neda Feizi Yadollah Yamini Morteza Moradi Behnam Ebrahimpour 《Journal of separation science》2016,39(17):3400-3409
A novel supramolecular solvent‐based microextraction followed by high‐performance liquid chromatography with ultraviolet detection method has been developed for the extraction and determination of two pyrethroid analytes, cyhalothrin and fenvalerate, in water and soil samples. The liquid–liquid‐phase separation of surfactants has been used in analytical extraction. The surfactant‐rich phase is a nano‐structured liquid, recently named as a supramolecular solvent, generated from the amphiphiles. The alkyl carboxylic acid based supramolecular solvents were introduced before. Coacervates made up of gemini surfactant, consisting of two amphiphilic moieties, were first used as solvent. The effective parameters on extraction (i.e., type of organic solvent, the amount of surfactant and volume of tetrahydrofuran, sample solution pH, salt addition, ultrasonic and centrifugation time) were investigated and optimized. Under the optimum conditions, preconcentration factors of 110 and 145 were obtained for the analytes. The linearity was 0.5–200.0 μg/L with the correlation of determination of (R2) ≥ 0.9984. The limit of detection of the method was (S/N = 3) 0.2 μg/L, and precisions in the range of 6.3–10.3% (RSDs, n = 5) were obtained. This method has been successfully applied to analyze real samples, and good recoveries in the range of 101.2–108.8% were obtained. 相似文献
48.
49.
Nonlinear Dynamics - Inclusion of redundancy has been one of the primary techniques to reduce the probability of error and to achieve reliability in computing systems and many other engineered... 相似文献
50.
Ahmad Shaabani Mozhdeh Seyyedhamzeh Ali Maleki Maryam Behnam Fahimeh Rezazadeh 《Tetrahedron letters》2009,50(24):2911-4167
A one-pot four-component reaction of an aliphatic or aromatic amine, diketene, an aromatic aldehyde and 1,3-diphenyl-1H-pyrazol-5-amine in the presence of p-toluenesulfonic acid as a catalyst has been developed. In this reaction, a new class of fully substituted pyrazolo[3,4-b]pyridine-5-carboxamide derivatives is produced under mild reaction conditions and in good yields at ambient temperature. 相似文献