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951.
Unique Fluorogenic Ratiometric Fluorescent Chemodosimeter for Rapid Sensing of CN− in Water
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Dr. Ajit Kumar Mahapatra Kalipada Maiti Saikat Kumar Manna Rajkishor Maji Chitrangada Das Mukhopadhyay Bholanath Pakhira Prof. Sabyasachi Sarkar 《化学:亚洲杂志》2014,9(12):3623-3632
A new benzimidazole‐spiropyran conjugate chemosensor molecule ( BISP ) has been synthesized and characterized by 1H NMR spectroscopy, mass spectrometry (ESI‐MS), and elemental analysis. The two isomeric forms ( BISP ? BIMC ) were shown to be highly selective and sensitive to CN? among the ten anions studied in aqueous HEPES buffer, as shown by fluorescence and absorption spectroscopy and even by visual color changes, with a detection limit of 1.7 μM for BIMC . The reaction of CN? with BIMC was monitored by 1H NMR spectroscopy, high‐resolution mass spectrometry (HRMS), UV/Vis measurements, and fluorescence spectroscopy in HEPES buffer of pH 7.4. TDDFT calculations were performed in order to correlate the electronic properties of the chemosensor with its cyanide complex. Further, titration against thiophilic metal ions like Au3+, Cu2+, Ag+, and Hg2+ with [ BIMC‐CN ] in situ showed that it acts as a secondary recognition ensemble toward Au3+ and Cu2+ by switch‐on fluorescence. In addition, a reversible logic‐gate property of BIMC has been demonstrated through a feedback loop in the presence of CN? and Au3+ ions, respectively. Furthermore, the use of BIMC to detect CN? in live cells by fluorescence imaging has also been demonstrated. Notably, test strips based on BIMC were fabricated, which could serve as convenient and efficient CN? test kits. 相似文献
952.
Cristina Nú?ez Sergio M Santos Elisabete Oliveira Hugo M Santos José Luis Capelo Carlos Lodeiro 《ChemistryOpen》2014,3(5):190-198
A new bipyridyl derivative 1 bearing rhodamine B as visible fluorophore was designed, synthesized and characterized as a fluorescent and colorimetric sensor for metal ions. Interaction with Cu2+, Zn2+, Cd2+, Hg+, and Hg2+ ions was followed by UV/Vis and emission spectroscopy. Upon addition of these metal ions, different colorimetric and fluorescent responses were observed. “Off-on-off” (Cu2+, Zn2+, and Hg2+) and “off-on” (Hg+ and Cd2+) systems were obtained. Probe 1 was explored to mimic XOR and OR logic operations for the simultaneous detection of Hg+–Cu2+ and Hg+–Zn2+ pairs, respectively. DFT calculations were also performed to gain insight into the lowest-energy gas-phase conformation of free receptor 1 as well as the atomistic details of the coordination modes of the various metal ions. 相似文献
953.
Christian Espíndola 《Annals of Pure and Applied Logic》2019,170(2):137-162
We present a unified categorical treatment of completeness theorems for several classical and intuitionistic infinitary logics with a proposed axiomatization. This provides new completeness theorems and subsumes previous ones by Gödel, Kripke, Beth, Karp and Joyal. As an application we prove, using large cardinals assumptions, the disjunction and existence properties for infinitary intuitionistic first-order logics. 相似文献
954.
955.
The paper presents a semantics for quantified modal logic which has a weaker axiomatization than the usual Kripke semantics. In particular, the Barcan Formula (BF) and its converse are not valid with the proposed semantics. Subclasses of models which validate BF and other interesting formulas are presented. A completeness theorem is proved, and the relation between this result and completeness with respect to Kripke models is investigated. 相似文献
956.
Petr Cintula 《Archive for Mathematical Logic》2006,45(6):673-704
This paper presents two classes of propositional logics (understood as a consequence relation). First we generalize the well-known class of implicative logics of Rasiowa and introduce the class of weakly implicative logics. This class is broad enough to contain many “usual” logics, yet easily manageable with nice logical properties. Then we introduce its subclass–the class of weakly implicative fuzzy logics. It contains the majority of logics studied in the literature under the name fuzzy logic. We present many general theorems for both classes, demonstrating their usefulness and importance.The work was supported by grant A100300503 of the Grant Agency of the Academy of Sciences of the Czech Republic and by Institutional Research Plan AVOZ10300504. 相似文献
957.
Ivo Herzog 《Algebras and Representation Theory》2007,10(2):135-155
Given an R-T-bimodule
R
K
T
and R-S-bimodule
R
M
S
, we study how properties of
R
K
T
affect the K-double dual M** = Hom
T
[Hom
R
(M, K), K] considered as a right S-module. If
R
K is a cogenerator, then for every R-S-bimodule, the natural morphism Φ
M
: M → M** is a pure-monomorphism of right S-modules. If
R
K is the minimal (injective) cogenerator and K
T
is quasi-injective, then M
** is a pure-injective right S-module. If
R
K is the minimal (injective) cogenerator, and T = End
R
K it is shown that K
T
is quasi-injective if and only if the K-topology on R is linearly compact. If the
R
K-topology on R is of finite type, then the natural morphism Φ
R
: R → R** is the pure-injective envelope of R
R
as a right module over itself.
The author is partially supported by NSF Grant DMS-02-00698. 相似文献
958.
本文提出了一种硬件实现模糊决策的方法,从理论上论证了这种方法的正确性,并通过实验证明其可行。它可以应用于模糊硬件系统,以实现对连续或离散模糊信号的去模糊。 相似文献
959.
960.
V. F. Murzina 《Algebra and Logic》2008,47(6):405-419
Using the language of temporal logic, we construct a decidable calculus L* α and prove that the calculus is complete w.r.t.
the class of all strictly linearly ordered α-frames.
Supported by RFBR (project No. 06-01-00358) and by the Council for Grants (under RF President) and State Aid of Leading Scientific
Schools (grant NSh-335.2008.1).
__________
Translated from Algebra i Logika, Vol. 47, No. 6, pp. 723–749, November–December, 2008. 相似文献