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141.
Nanoparticles (NPs)-based electrochemical devices are generating a growing interest and optical microscopy has recently proven to be a powerful tool to apprehend their electrochemical behavior. Through several striking examples, this review demonstrates how label-free optical imaging coupled to an electrochemical actuation can be used to probe operando the physical and electrochemical properties of single NPs, with high resolution and sensitivity and without additional emitters. Such an approach can be particularly relevant to establish clear structure-motion/reactivity relationships required to optimize NPs exploited as electrode materials. 相似文献
142.
The Ramanujan Journal - Let $${\mathcal {A}}$$ , $${\mathcal {B}}$$ be large subsets of $$\{1,\ldots ,N\}$$ . We study the distribution of the sum of binary digits of the sums $$a+b$$ with... 相似文献
143.
144.
Analysis and fragmentation mechanisms of hirsutinolide‐type sesquiterpene lactones by ultra‐high‐performance liquid chromatography/electrospray ionization linear ion trap Orbitrap mass spectrometry 下载免费PDF全文
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146.
In this paper, a symmetric nonnegative matrix with zero diagonal and given spectrum, where exactly one of the eigenvalues is positive, is constructed. This solves the symmetric nonnegative eigenvalue problem (SNIEP) for such a spectrum. The construction is based on the idea from the paper Hayden, Reams, Wells, “Methods for constructing distance matrices and the inverse eigenvalue problem”. Some results of this paper are enhanced. The construction is applied for the solution of the inverse eigenvalue problem for Euclidean distance matrices, under some assumptions on the eigenvalues. 相似文献
147.
Thomas Michel Emilie Destandau Laëtitia Fougère Claire Elfakir 《Analytical and bioanalytical chemistry》2013,405(4):1431-1431
148.
This paper is devoted to the study of the photochemical processes occurring during hologram formation in a biopolymer, agar doped by chromium(VI). The evolution of both the absorbing chromium species and the polymer allowed elucidating the reactions taking place during irradiation in conditions representative of hologram formation. As previously observed with dichromated poly(vinyl alcohol) (PVA), polymer containing hydroxyl groups as agar, irradiation of dichromated agar provoked a two step reduction of chromium species and the crosslinking of the host polymer. But agar has a rather complex chemical structure and the photoproducts formed along the polymeric chains throughout the photoredox process were different in agar and in PVA. The photostability of the matrix, that has been proven, coupled with the possibility to record good quality holograms, allowed us to propose dichromated agar as a new natural photosensitive biomaterial. 相似文献
149.
F. Mathey N. Maigrot C. Charrier 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4)
Abstract The reaction of compounds (1) with lithium or sodium can lead to different results depending on the length of the exocyclic chain : when n=1,2 or 4, we observe cleavage of both exocyclic P-C bonds, giving pure phospholyllithium or sodium. 相似文献
150.
Christelle Mouveaux Fabienne Hochart Joëlle Levalois-Mitjaville Roger De Jaeger 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Multisite receptors containing more than two macrocyclic cavities. despite of the fact that their syntheses, most often, require sophisticated pathways, arc of very high interest since they may allow new insights into ion channel transfer, ion conduction.[1] We report here a method which combine simple reactions, high yields (80%), with easily prepared starting reagents[2], of two new polymacrocyclic system, a tri-(r) and an hexamacrocyck(II). They were obtained by a condensation reaction between 4-formylbenzo-15-crown-5 (3 or 6 quiv, respectively) and phosphouihydrazide (1 equiv.) or hexahydrazide (1 equiv.) in tetrahydrofuran. 相似文献