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51.
Anselm of Cantorbery wrote Proslogion (1077–1078), where is formulated the famous ‘Unum argumentum’ about the existence of God. This argument was been disputed and criticized by numerous logicians from an extensional view point. The classical predicate logic is not able to give a formal frame to develop an adequate analysis of this argument. According to us, this argument is not an ontological proof; it analyses the meaning of the “quo nihil maius cogitari posit”, a characterization of God, and establish, by absurd, that “quod non posit cogitare non esse” by using the hypothesis: “to think in re” is taller than “to think in solo intelectu”. We discuss this relation and the difference between the meanings of the elementary predicates ‘to be in re’, ‘to be in intellectu’ and ‘to be in solo intellectu’. We propose a new logical approach of this ‘Unum argumentum’ of Anselm by using Curry’s Combinatory Logic (1958, 1973). Indeed, Combinatory Logic is an abstract applicative formalism of operators applied to operands; in this formalism, the predicates, viewed as specific operators, can be composed and can be transformed, by an intrinsic way, into more complex predicates, by means of abstract operators, called “combinators”, studied by Combinatory Logic. We show that this formalism is a logical frame where it becomes possible to discuss and to formulate cognitive representations of the meanings of predicates used inside of the ‘Unum argumentum’ and to explain how the argument runs.  相似文献   
52.
Journal of Solid State Electrochemistry - We report the electrochemical behavior of free-standing functionalized graphene sheet electrode in a potential window corresponding to that of high-voltage...  相似文献   
53.
Herein, novel silver-based N-heterocyclic carbene (NHC) complexes bearing 2-(4-hydroxyphenyl)ethyl group were synthesized. Novel Ag(I)NHC complexes were synthesized from the 2-(4-hydroxyphenyl)ethyl-substituted benzimidazolium salts and silver oxide via in situ deprotonation method. The successful formation of all Ag(I)NHC complexes was proved by using 1H NMR, 13C NMR, FTIR spectroscopy, and elemental analysis techniques. In addition, their inhibitory effects have been investigated of these substances on acetylcholinesterase (AChE), α-glycosidase (α-Gly), human carbonic anhydrase I (hCA I), and human carbonic anhydrase II (hCA II) enzymes. It has been seen that all compounds have a better ability to inhibit compared with existing tried inhibitors. Among these, the best inhibitor against AChE enzyme is 1g (Ki : 9.54 ± 0.98 μM and IC50 : 17.40), and against α-Gly, 1c showed the highest effect (Ki 3.09 ± 0.36 μM and IC50 7.91). The best inhibitor against hCA I and hCA II enzymes are 1c and 1g compounds. For hCA I and hCA II, IC50 values were calculated as 17.85 and 9.06 μM and Ki values were measured as 5.45 ± 2.02 and 8.99 ± 2.02 μM, respectively.  相似文献   
54.
The structure of uleine type alkaloids is characterized by the presence of a bridged tetracyclic hexahydro-1H-1,5-methanoazocino[4,3-b]indole ring system 1 . Various strategies have been developed to access this polycyclic structural motif. We report herein a one-step conversion of appropriately functionalized 1,3,4-trisubstituted cyclopent-1-ene to 1 by way of an integrated oxidation/reduction/cyclization (iORC) process. This domino sequence, initiated by oxidative cleavage of cyclopentene ring, generated subsequently a cyclohexenone, an indole and a 1,3-bridged piperidine ring through formation of one C−C and two C−N bonds. Compound 1 is subsequently converted to nordasycarpidone, dasycarpidone and uleine. The chirality of the molecule was introduced by enzymatic desymmetrization of commercially available meso cis-3,5-diacetoxy-1-cyclopentene.  相似文献   
55.
Journal of Mathematical Chemistry - In this work we perform analytical and statistical studies of the Rodríguez–Velázquez (RV) indices on graphs G. The topological RV(G) indices,...  相似文献   
56.
Poon  Clarice  Peyré  Gabriel 《Mathematical Programming》2023,201(1-2):897-952
Mathematical Programming - Non-smooth optimization is a core ingredient of many imaging or machine learning pipelines. Non-smoothness encodes structural constraints on the solutions, such as...  相似文献   
57.
Journal of Solution Chemistry - In this work, a robust and rigorous procedure for roots calculation and selection for a Cubic Equation of State is presented. Roundoff errors are detected and...  相似文献   
58.
Plasma Chemistry and Plasma Processing - The influence of plasma power on liquid precursor decomposition in suspension plasma spray (SPS) is studied with optical emission spectroscopy (OES). The...  相似文献   
59.
60.
Cationic triangulenes, and related helicenes, constitute a rich class of dyes and fluorophores, usually absorbing and emitting light at low energy, in the orange to red domains. Recently, to broaden the scope of applications, regioselective late-stage functionalizations on these core moieties have been developed. For instance, with the introduction of electron-donating groups (EDGs), important bathochromic shifts are observed pushing absorptions towards or in the near-infrared (NIR) spectral domain while emissive properties disappear essentially completely. Herein, to upset this drawback, acetylene derivatives of cationic diazaoxa triangulenes (DAOTA) and [4]helicenes are prepared (16 examples). Contrary to other EDG-functionalized derivatives, C≡C− functionalized products remain broadly fluorescent, with red-shifted absorptions (Δλabs up to 25 nm) and emissions (Δλem up to 73 nm, ΦPL up to 51 %). Quite interestingly, a general dynamic stereoisomerism phenomenon is evidenced for the compounds derived from achiral DAOTA cores. At low temperature in 1H NMR spectroscopy (218 K), N−CH2 protons become diastereotopic with chemical shifts differences (Δδ) as high as +1.64 ppm. The signal coalescence occurs around 273 K with a barrier of ∼12 kcal mol−1. This phenomenon is due to planar chiral conformations (Sp and Rp configurations), induced by the geometry of the alkyl (n-propyl) side-chains next to the acetylenic substituents. Ion pairing studies with Δ-TRISPHAT anion not only confirm the occurrence of the chiral conformations but evidence a moderate but definite asymmetric induction from the chiral anion onto the cations. Finally, DFT calculations offer a valuable insight on the geometries, the corresponding stereodynamics and also on the very large difference in NMR for some of the diastereotopic protons.  相似文献   
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