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91.
A general, practical and efficient one-pot synthesis of cyclic enecarbamates is described. The protocol proceeds via reduction of lactam carbamate with Super-Hydride®, followed by in situ dehydration with trifluoroacetic anhydride (TFAA) and diisopropylethylamine (DIPEA). 相似文献
92.
The unique advantages of quantum dot (QD) bioconjugates have motivated their application in biological assays. However, physical characterization of bioconjugated QDs after surface modification has often been overlooked. Here, biotinylated antibodies (biotin-IgG) were attached to commercial streptavidin-conjugated quantum dots (strep-QDs) at different stoichiometric ratios, and these QD bioconjugates were characterized with atomic force microscopy and discontinuous sodium dodecyl sulfate agarose gel electrophoresis (SDS-AGE). The results from these complementary analytical techniques showed that the molar ratio determined the relative sizes, molecular weights and morphologies of the QD bioconjugates. Additionally, the novel discontinuous SDS-AGE analysis confirmed specific binding between biotin-IgG and strep-QDs. Researchers who design QD bioconjugates for cell-based assays should consider stoichiometry-dependent differences in the physical properties of their QD bioconjugates. 相似文献
93.
Breakdown conditions for creation of the hollow cathode discharge in the nozzle passed through the rf powered electrode and creation of the plasma jet channel in PCVD reactor are studied. Pure nitrogen is used for measurements. The creation of jet channel is easier for smaller rf electrodes. The breakdown depends on the pressure and on the gas inflow rate. The plasma potential and the self-bias potential is influenced by the covering of reactor walls and the rf electrode by a dielectric layer. 相似文献
94.
95.
Learning to teach is difficult for prospective teachers because of the complex nature of the work of teaching. Practicing (Lampert in J Teach Educ 61(1–2):21–34, 2010), interacting with the practice of teaching from a first-person perspective, may give them a unique experience in learning to teach. Computer-based simulators in which the apprentice teacher can interact with virtual students may be used to create that kind of experience. In this paper, we show how to apply techniques in artificial intelligence to design an intelligent learning environment. We show how to model the apprentice’s decision making and resources that can help him or her improve the practice of teaching. 相似文献
96.
Pierre Aboulker Marko Radovanović Nicolas Trotignon Théophile Trunck Kristina Vušković 《Journal of Graph Theory》2014,75(2):150-166
In Math Program 55(1992), 129–168, Conforti and Rao conjectured that every balanced bipartite graph contains an edge that is not the unique chord of a cycle. We prove this conjecture for balanced bipartite graphs that do not contain a cycle of length 4 (also known as linear balanced bipartite graphs), and for balanced bipartite graphs whose maximum degree is at most 3. We in fact obtain results for more general classes, namely linear balanceable and subcubic balanceable graphs. Additionally, we prove that cubic balanced graphs contain a pair of twins, a result that was conjectured by Morris, Spiga, and Webb in ( Discrete Math 310(2010), 3228–3235). 相似文献
97.
Vu Kim Tuan 《Results in Mathematics》2013,63(1-2):303-309
Boundaries of convex and compact spectra of functions on plane are fully described without passing to the complexification and the Fourier transform. 相似文献
98.
Roussel and Rubio proved a lemma which is essential in the proof of the Strong Perfect Graph Theorem. We give a new short proof of the main case of this lemma. In this note, we also give a short proof of Hayward’s decomposition theorem for weakly chordal graphs, relying on a Roussel–Rubio-type lemma. We recall how Roussel–Rubio-type lemmas yield very short proofs of the existence of even pairs in weakly chordal graphs and Meyniel graphs. 相似文献
99.
Nguyen H. N. Vu M. A. Hy D. M. Ta N. A. Do A. T. 《Journal of Applied and Industrial Mathematics》2021,15(2):315-325
Journal of Applied and Industrial Mathematics - In this paper, we introduce a nonlinear Lanchester-type model involving supply units. The model describes a battle where the Blue party consisting of... 相似文献
100.
We experimentally presented the electromagnetic behavior of transformative magnetic metamaterials: from the early invented
split-ring resonator to its improvement, the cut-wire pair, for providing a negative magnetic permeability. By adding the
continuous wire to cut-wire pair structure, the left-handed (LH) transmission made by doubly negative permittivity and permeability
was demonstrated in combined structure. Interestingly, until the width of cut-wire pair increases to be physically merged
with the adjacent continuous wire, in other words, to form the so-called fishnet structure, the LH behavior is still observed.
This result indicates that in a broad sense, the essence of the electromagnetic response in the fishnet structure is similar
to that in a combined structure. Our experimental results show a good agreement with previous theoretical study. 相似文献