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1.
Nilgün KABAY Yasemin BAYGU Metin AK zzet KARA EsraNur KAYA Mahmut DURMU Yaar G
K 《Turkish Journal of Chemistry》2021,45(1):143
The current study describes the synthesis, electrochemical, computational, and photochemical properties of octa (3-hydroxypropylthio) substituted cobalt (II) ( 4 ), copper (II) ( 5 ), nickel (II) ( 6 ) and zinc(II) ( 7 ) phthalocyanine derivatives. These novel compounds were characterized by elemental analysis,1H,13C NMR, FT-IR, UV-Vis, and MS. The redox behaviors of these metallo-phthalocyanines were investigated by the cyclic voltammetric method. The optimized molecular structure and gauge-including atomic orbital (GIAO)1H and13C NMR chemical shift values of these phthalocyanines in the ground state had been calculated by using B3LYP/6–31G(d,p) basis set. The outcomes of the optimized molecular structure were given and compared with the experimental NMR values. The photochemical properties including photodegradation and singlet oxygen generation of zinc(II) phthalocyanine were studied in DMSO solution for the determination of its photosensitizer behaviors. 相似文献
2.
Fatma KARA Duygu ADIGÜZEL Ufuk ATMACA Murat ELK Jale NAKTYOK 《Turkish Journal of Chemistry》2020,44(6):1483
A humic substance was obtained from hazelnut husk using an alkali extraction. The chemical and morphological structure of the humic matter was characterized via elemental analysis, Fourier transform infrared spectrometry (FTIR), nuclear magnetic resonance, Brunauer-Emmet-Teller (BET) analysis, scanning electron microscopy (SEM), and thermogravimetric-FTIR (TG-FTIR). In addition, thermal analysis measurements TG analysis-differential thermogravimetry/differential scanning calorimetry (TGA-DTG/DSC) were performed under dynamic air conditions to better determine the origin, physical and chemical structure, and decomposition process of the humic matter. The Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods were used to calculate the kinetic parameters of the high-temperature decomposition process. It was observed that the activation energy values were almost constant at certain conversion and temperature intervals. In addition, the structure of the humic substance at different temperatures was also investigated via FTIR analysis. It was found that the obtained humic substance had a very stable structure and decomposed at a high temperature. The stability of the humic matter can be a useful tool in the environmental quality research of soil. 相似文献
3.
KARA E. RANAGHAN LARS RIDDER BORYS SZEFCZYK W. ANDRZEJ SOKALSKI JOHANNES C. HERMANN ADRIAN J. MULHOLLAND 《Molecular physics》2013,111(17):2695-2714
Chorismate mutase provides an important test of theories of enzyme catalysis, and of modelling methods. The Claisen rearrangement of chorismate to prephenate in the enzyme has been modelled here by a combined quantum mechanics/molecular mechanics (QM/MM) method. Several pathways have been calculated. The sensitivity of the results to details of model preparation and pathway calculation is tested, and the results are compared in detail to previous similar studies and experiments. The potential energy barrier for the enzyme reaction is estimated at 24.5—31.6 kcal mol?1 (AMl/CHARMM), and 2.7—11.9 kcal mol?1 with corrections (e.g. B3LYP/6-31 + G(d)). In agreement with previous studies, the present analysis of the calculated paths provides unequivocal evidence of significant transition state stabilization by the enzyme, indicating that this is central to catalysis by the enzyme. The active site is exquisitely complementary to the transition state, stabilizing it more than the substrate, so reducing the barrier to reaction. A number of similar pathways for reaction exist in the protein, as expected. Small structural differences give rise to differences in energetic contributions. Major electrostatic contributions to transition state stabilization come in all cases from Arg90, Arg7, one or two water molecules, and Glu78 (Glu78 destabilizes the transition state less than the substrate), while Arg63 contributes significantly in one model. 相似文献
4.
In this work, we study the similarity analysis of the generalized nonlinear Burgers' equation having diffusivity and viscosity as a general functions of the particle velocity. We perform the symmetry analysis and exhibit exact solutions for various forms of the diffusivity and viscosity. 相似文献
5.
对一只旅居美国的青年雌性大熊猫在休情期和发情期的阴道角化细胞变化作了连续监测.结果表明:休情期间低于35%。发情期间平均高于80%.当角化率上升到70%左右时.提示动物发情期开始;上升至90%左右,表明已进入发情高潮期,是配种良机.其结果与尿激素水平和行为表现相比较,三者具有高度一致性,证明阴道角化细胞变化监测对判定大熊猫的发情及配种时机具有良好的指示意义。 相似文献
6.
In this paper a class of multi-dimensional Gordon-type equations are analysed using a multiplier and homotopy approach to
construct conservation laws. The main focus is the analysis of the classical versions of the Gordon-type equations and obtaining
higher-order variational symmetries and corresponding conserved quantities. The results are extended to the multi-dimensional
Gordon-type equations with the two-dimensional Klein–Gordon equation in particular yielding interesting results. 相似文献
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The ASD systems and manifolds have been studied via a number of approaches and their origins have been well documented. In this paper, we look at the symmetry structures, variational symmetries and related concepts around the associated conservation laws for a number of such manifolds. 相似文献
9.
Lie point symmetries of the first-order inviscid Burgers equation in a general setting are studied. Some new and interesting
solutions are presented. 相似文献
10.
Zahid Hussain LAGHARI Syed Tufail Hussain SHERAZI Hamide Filiz AYYILDIZ Mustafa TOPKAFA Hüseyin KARA Sarfaraz Ahmed MAHESAR Sirajuddin . 《Turkish Journal of Chemistry》2020,44(6):1694
In the present study, high-performance liquid chromatography (HPLC) was used for the separation of tocopherols and triglycerides of processed soybean oil and deodorizer distillate (DD). The results of normal and reversed-phase modes of HPLC revealed that concentrations of tocopherols and triglycerides content were decreased during the neutralization, bleaching, and deodorization processes. The loss of individual tocopherols ranged between 55.16% and 63.25%. During processing, triglycerides containing stearic-oleic-linoleic (SOL) moieties and palmitic-palmitic-linoleic (PPL) fragments showed greater reduction up to 38.14% and 37.69%, respectively. Among tocopherols and triglycerides; γ-tocopherol and oleic-oleic-oleic (OOO) were found to be in greater concentrations 5.53% and 19.78%, respectively in DD as compared to their counterparts. A maximum reduction of tocopherols was observed in the deodorization step. DD was found to be a rich source of bioactive components; therefore, it could be used for many industrial applications including pharmaceutical formulations, cosmetics, and food industries. 相似文献