• 제목/요약/키워드: science and arts

검색결과 3,124건 처리시간 0.026초

炭素二重結合에 대한 Mercaptan의 친핵성 첨가 반응의 Extrathermodynamic Relationship에 관한 연구 (Extrathermodynamic Relationships for the Nucleophilic Addition Reaction of Mercaptan to a Carbon Double Bond)

  • 박옥현;엄태섭
    • 대한화학회지
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    • 제13권4호
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    • pp.297-302
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    • 1969
  • The activation parameters for the nucleophilic addition reactions of n-propyl-, n-butyl-, n-amyl-and n-hexyl-mercaptan to 3, 4-methylene-dioxy-${\beta}$-nitrostyrene were determined at pH 5.8 and pH 2.0, and also the isokinetic temperature of the reactions at pH 5.8 was obtained numerically 262${\circ}$K, and at pH 2.0, 17.1${\circ}$K. From the values obtained above, the fact that the mercaptan having the longer carbon chain has the greater nucleophilicity of it in the addition reactions has been discussed by the extrathermodynamic analysis of ${\Delta}H^{\neq}$and ${\Delta}S^{\neq}$.

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UTILIZING ISOTONE MAPPINGS UNDER GERAGHTY-TYPE CONTRACTION TO PROVE MULTIDIMENSIONAL FIXED POINT THEOREMS WITH APPLICATION

  • Deshpande, Bhavana;Handa, Amrish
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제25권4호
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    • pp.279-295
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    • 2018
  • We study the existence and uniqueness of fixed point for isotone mappings of any number of arguments under Geraghty-type contraction on a complete metric space endowed with a partial order. As an application of our result we study the existence and uniqueness of the solution to a nonlinear Fredholm integral equation. Our results generalize, extend and unify several classical and very recent related results in the literature in metric spaces.

DESIGN OF A MODERN COMPUTER BRAND AS THE MAIN COMMUNICATION FACTOR IN THE WORLD CULTURAL SPACE

  • Zaitseva, Veronika;Bratus, Ivan;Sverdlyk, Zoriana;Gunka, Anna;Liezhniev, Olexandr
    • International Journal of Computer Science & Network Security
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    • 제21권9호
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    • pp.292-296
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    • 2021
  • The purpose of this article is to explore the modern branding - its nature, history, originality, spirit and value to consumers. In particular, graphic design of the brand is an important component in terms of the modern European culture. The scientific novelty of the work implies the study of the contemporary design, which widely embraces the sphere of cultural and social life and can contribute to the development of progressive phenomena in society, as the design can literally be defined as a rethinking, a search for new meanings. The design itself is a versatile means of communication at the level of feelings and meanings. One of its main goals is the harmonization, and even formation of perception of the world, creation of new images or rethinking the essence of ordinary things. Hence, the research in the field of the design development is topical in the worldwide cultural space..

Metallo-collagenase production by Arthrobacter creatinolyticus KP015744

  • Savita A. Kate;Madhuri Sahasrabudhe;Archana Pethe
    • Advances in environmental research
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    • 제11권1호
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    • pp.1-16
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    • 2022
  • Amongst 27 isolates from deteriorated leather samples, Arthrobacter creatinolyticus KP015744 zzx28 was found to be an efficient collagenase producer. Collagenase production of 13.33 µmoles/min was shown at an optimum temperature at 37℃ after 72h and at pH 7.5 by using 2 ml/dL inoculum in 10 mg/ml collagen peptide type I as a substrate. In presence of Hg2+, EDTA and 𝛽-mercaptoethanol the collagenase production by the isolate was strongly inhibited however Fe2+, Ca2+and DMSO enhanced production of the enzyme. Specific activity was found to be 19.46×103 U/mg and molecular weight 66 kD by SDS PAGE. Isolate also has potential to hydrolyze keratin which is another important protein found in leather. Experimental results propose that collagenase can be effectively used as a tool for collagen and keratin rich solid waste treatment.

Locating-Hop Domination in Graphs

  • Canoy, Sergio R. Jr.;Salasalan, Gemma P.
    • Kyungpook Mathematical Journal
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    • 제62권1호
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    • pp.193-204
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    • 2022
  • A subset S of V(G), where G is a simple undirected graph, is a hop dominating set if for each v ∈ V(G)\S, there exists w ∈ S such that dG(v, w) = 2 and it is a locating-hop set if NG(v, 2) ∩ S ≠ NG(v, 2) ∩ S for any two distinct vertices u, v ∈ V(G)\S. A set S ⊆ V(G) is a locating-hop dominating set if it is both a locating-hop and a hop dominating set of G. The minimum cardinality of a locating-hop dominating set of G, denoted by 𝛄lh(G), is called the locating-hop domination number of G. In this paper, we investigate some properties of this newly defined parameter. In particular, we characterize the locating-hop dominating sets in graphs under some binary operations.

A NEW PARANORMED SERIES SPACE USING EULER TOTIENT MEANS AND SOME MATRIX TRANSFORMATIONS

  • Gulec, G. Canan Hazar;Ilkhan, Merve
    • Korean Journal of Mathematics
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    • 제28권2호
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    • pp.205-221
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    • 2020
  • Paranormed spaces are important as a generalization of the normed spaces in terms of having more general properties. The aim of this study is to introduce a new paranormed space |𝜙z|(p) over the paranormed space ℓ(p) using Euler totient means, where p = (pk) is a bounded sequence of positive real numbers. Besides this, we investigate topological properties and compute the α-, β-, and γ duals of this paranormed space. Finally, we characterize the classes of infinite matrices (|𝜙z|(p), λ) and (λ, |𝜙z|(p)), where λ is any given sequence space.

A New Family of q-analogue of Genocchi Numbers and Polynomials of Higher Order

  • Araci, Serkan;Acikgoz, Mehmet;Seo, Jong Jin
    • Kyungpook Mathematical Journal
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    • 제54권1호
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    • pp.131-141
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    • 2014
  • In the present paper, we introduce the new generalization of q-Genocchi polynomials and numbers of higher order. Also, we give some interesting identities. Finally, by applying q-Mellin transformation to the generating function for q-Genocchi polynomials of higher order put we define novel q-Hurwitz-Zeta type function which is an interpolation for this polynomials at negative integers.

막장의 아미노酸 組成에 關한 硏究 (Studies on the Amino Acids Composition of Makjang)

  • 신홍대;윤주억
    • 대한화학회지
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    • 제7권1호
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    • pp.6-12
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    • 1963
  • Amino acid composition of Makjang was determined by combined usage of ion exchanged resin and paper chormatography in the following states. a. A fraction soluble in water b. Hydrolysate of the whole Makjang c. Same as a. (p.p.t. formed by tungstic acid or trichloroacetic acid being removed) d. Hydrolysate of c. (T and TCA) By comparing amino acid composition of Makjang with that of its raw material, we found that decomposition of essential amino acids during brewing is slight. From the amino acid composition of a,b,c,d, we discussed the ratio of amino acid liberation during brewing and assumed that Makjang contains peptide-like substances composing of glutamic acid and aspartic acid.

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Synthesis, Characterization and Biological Evaluations of Ciprofloxacin Carboxamide Analogues

  • Sultana, Najma;Arayne, Muhammad Saeed;Rizvi, Syeda Bushra Shakeb;Haroon, Urooj
    • Bulletin of the Korean Chemical Society
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    • 제32권2호
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    • pp.483-488
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    • 2011
  • Present work comprises of synthesis various analogues of ciprofloxacin by introducing new functionality at carboxylic group position via ester aminolysis reaction. For this purpose the carboxylic group at C-3 was esterified and later subjected to nucleophilic attack at the carbonyl carbon by various aromatic amines. Structure of the analogues was confirmed by different techniques i.e. IR, $^1H$ NMR and mass spectrometry. The antibacterial activity of the derivatives was also assessed with the parent against a series of Gram-positive and Gram-negative bacteria. The synthesized compounds showed diverse antimicrobial profile among which most compounds possessed a comparable or better activity in comparison to the ciprofloxacin. Additionally unlike ciprofloxacin, some of the derivatives were also found to show antifungal activity.

Polarograph 에 依한 Monazite 鑛石속의 Uranium 의 定量에 關한 硏究 (Determination of Uranium in Monazite Sand by Polarographic Method)

  • 김황암;손병영
    • 대한화학회지
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    • 제5권1호
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    • pp.84-87
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    • 1961
  • A polarographic method for rapid determination of Uranium in the presence of foreign ions was proposed. The method is based on the measurement of polarogram in the sulfuric acid as supporting electrolyte. In this medium Uranyl ions give well defined reduction waves, and half-wave potentials are -0.19V vs. S.C.E. as first wave, and uncertain volt. vs. S.C.E. as second wave in $2.4 N-H_2SO_4.$ The first wave has a linear relationship between the concentration of Uranyl ion and wave height. The author also studied a method for rapid determination of Uranium in Korean monazite sand without eliminating the foreign ions. The Korean monazite sands were analyzed by this method and satisfactory result were obtained.

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