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41.
Herein, we report an approach to combat counterfeiting and storage of valuable information based on the solid‐state fluorescence switching behavior of isoniazid functionalized naphthalene diimide (ISO_NDI) in response to an external stimuli (i. e., HCl vapor). The unique feature of ISO_NDI is further utilized to develop an invisible ink (ISO_NDI‐PVA) with commercial polymer polyvinyl alcohol (PVA). A solid‐state fluorescence recovery was observed while loading with HCl vapors. This exclusive property of the material could be applied directly as a security ink for confidential data storage purpose. Based on above strategy, we successfully realized the rewritable application by using ISO_NDI‐PVA ink and confirm its practical efficacy on various substrates by creating different patterns. The solid‐state fluorescence switching behavior of ISO_NDI‐PVA ink exhibited reversible on/off signal for multiple cycles under the influence of HCl/NH3 vapors. Mechanistic investigation supports a clear participation of intermolecular charge transfer (ICT) phenomenon in the solid‐state fluorescence switching property. The ease of fabricating the ink with invisible to visible characteristics in response to HCl vapors provides new opportunities for exploring the application of ISO_NDI‐PVA as invisible ink for targeted security applications. 相似文献
42.
Prakasham RS Rao ChS Rao RS Rajesham S Sarma PN 《Applied biochemistry and biotechnology》2005,120(2):133-144
Optimization of alkaline protease production parameters by Bacillus sp. was investigated using Taguchi methodology. The pH of the medium was observed to be the most significant factor among
all selected optimization parameters at an individual level. The combinatorial influence of least significant factors, inoculum
level and salt solution concentration (at the individual level), resulted in an interacting severity index of 76%, suggesting
their interactive role in the regulation of protease production in this microbial species. Protease production could be improved
more than 100% with Taguchi’s optimized conditions of the medium composition by this microorganism. 相似文献
43.
U. Pandey A. Mukherjee G. Samuel S. Banerjee H. D. Sarma M. Venkatesh 《Journal of Radioanalytical and Nuclear Chemistry》2008,275(2):243-246
Lanreotide, a somatostatin analogue, was radioiodinated with 125I to explore the possibility of using 123I labeled lanreotide as a diagnostic radiopharmaceutical for tumors overexpressing somatostatin (SST) receptors. Radioiodination
was carried out with 125I using chloramine T as the oxidant. The labeling yield was >90%. Characterization of 125I-Lanreotide was carried out by paper electrophoresis as well as HPLC. 125I-Lanreotide was purified by chromatography using a C18 Sep-Pak column. Radiochemical purity of the purified 125I-Lanreotide thus obtained was >99%. Significant tumor uptake of 125I-Lanreotide was observed in C57BL/6 mice bearing melanoma. 相似文献
44.
45.
46.
Temperature dependent Mössbauer measurements are done on the samples of La1–x
Ca
x
Mn1–y
57Fe
y
O3 with x=0 and 0.25, and y=0.01. With decreasing temperature, the specimen with x=0.25 shows a paramagnetic to ferromagnetic transition around 175 K. In the specimen x=0.0, the temperature dependence of both the center shift () and the recoilless fraction (f) can be fitted very well with the Debye theory with a
D=320±50 K. But for the specimens with x=0.25, f and show distinct deviations from the Debye behavior in the temperature range in which the resistivity shows a sharp decrease. Dips observed in both the f and around the transition temperature suggest that the Jahn–Teller distortion observed in these systems is dynamic in nature. 相似文献
47.
A new compound of nickel(III), [Ni(OPPh3)Cl2I] has been prepared by the action of nitrosyl chloride or chlorine gas on [Ni(PPh3)2I2]. Various physical studies of the compound are reported. 相似文献
48.
Optical and EPR measurements are carried out on shattuckite, a copper bearing silicate. The EPR spectrum observed at 120 K reveales hyperfine structure for parallel and perpendicular components. The measured values are g6 = 2.402, g⊥ = 2.038, A6 = 112 × 10-4 cm-1 and A⊥ = 49.5 × 10-4 cm-1 and they indicate a tetragonal distortion for the Cu2+ion. Further, the constants P and K are evaluated and found to be 0.014 cm-1 and 0.0112 respectively. The bands observed at 8160, 13330 and 16125 cm-1 are assigned to the electronic states of Cu2+, in a crystal field subjected to tetragonal (C4V) distortion. The crystal field parameters evaluated are Dq = -1333, Ds = -1565 and Dt = -380 cm-1. Correlating the EPR and optical data, the orbital reduction factors are calculated as k6 = 0.89 and k⊥ = 0.59. It is confirmed from EPR and optical studies that the Cu2+ion in shattuckite is sited in an elongated octahedron. Similar studies are carried out for plancheite. The observed optical absorption spectrum of plancheite is attributed to Cu2+ sited in an elongated octahedron and tetragonal field parameters are evaluated. 相似文献
49.
Switching surfaces inN-person differential games are essentially similar to those encountered in optimal control and two-person, zero-sum differential games. The differences between the Nash noncooperative solution and the saddle-point solution are reflected in the dispersal surfaces. These are discussed through classification and construction procedures for switching surfaces. A simple example of a two-person, nonzero-sum game is considered. A complete solution of this game will be presented in a companion paper (Ref. 1). 相似文献
50.
It is pointed out that the coupling characterizing theψ-γ vertex must change substantially between the limits,ψ on mass-shell which occurs inψ→e
+
e
− and photon on mass-shell which is relevant in radiative decays likeψ→ππγ, ψ→ηγ and photoproduction ofψ. This has the consequence that the value ofψN total cross section must be larger than what is inferred from the use of naive vector dominance in photoproduction. 相似文献