European Journal of Chemistry最新文献_第2页

Synthesis of coumarin-3-carboxylic acids in waste curd water: A green approach 在凝乳废水中合成香豆素-3-羧酸：一种绿色方法

European Journal of Chemistry Pub Date : 2023-12-31 DOI: 10.5155/eurjchem.14.4.439-444.2471

N. B. Sonawane, J. Rajput, Dilip Ramsing Patil

引用次数: 0

A square planar copper(II) complex noncovalently conjugated with a p-cresol for bioinspired catecholase activity 与对甲酚非共价共轭的方形平面铜(II)配合物，具有生物启发的儿茶酚酶活性

European Journal of Chemistry Pub Date : 2023-12-31 DOI: 10.5155/eurjchem.14.4.499-506.2489

Subham Mukherjee, Gayetri Sarkar, A. De, Bhaskar Biswas

{"title":"A square planar copper(II) complex noncovalently conjugated with a p-cresol for bioinspired catecholase activity","authors":"Subham Mukherjee, Gayetri Sarkar, A. De, Bhaskar Biswas","doi":"10.5155/eurjchem.14.4.499-506.2489","DOIUrl":"https://doi.org/10.5155/eurjchem.14.4.499-506.2489","url":null,"abstract":"This work presents the synthesis of an unprecedented p-cresol-conjugated copper(II) complex as a p-cresol-coupled polydentate ligand, its crystal structure, and catecholase activity. X-ray crystallography reveals that the Cu(II) centre adopts a nearly planar coordination geometry. Crystal data for C14H13Cu0.5O3: Monoclinic, space group P21/c (no. 14), a = 5.9204(2) Å, b = 21.5615(10) Å, c = 9.0715(4) Å, β = 91.266(4)°, V = 1157.72(8) Å3, Z = 4, μ(MoKα) = 0.987 mm-1, Dcalc = 1.498 g/cm3, 12647 reflections measured (6.884° ≤ 2Θ ≤ 63.42°), 3233 unique (Rint = 0.0618, Rsigma = 0.0512) which were used in all calculations. The final R1 was 0.0710 (I > 2σ(I)) and wR2 was 0.2173 (all data). The crystallized p-cresol was localized in complex units through intermolecular O···H interactions and formed a 3D supramolecular framework employing short-ranged O···H and C-H···π interactions in the solid state. The copper(II) complex has been evaluated as a bioinspired catalyst in the oxidative transformation of 3,5-di-tert-butylcatechol (DTBC) to o-benzoquinone in acetonitrile with a high turnover number, 2.26´104 h–1. Electrochemical analysis of the copper(II) complex in the presence of DTBC recommends the generation of a catechol/o-benzosemiquinone redox couple during catalytic oxidation with the generation of hydrogen peroxide as a byproduct.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"17 25","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139130234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of UV radiation on postharvest conservation of blueberries 紫外线辐射对蓝莓采后保存的影响

European Journal of Chemistry Pub Date : 2023-12-31 DOI: 10.5155/eurjchem.14.4.473-477.2473

Eliana Vanesa Campero, Maria Julia Barrionuevo, A. C. G. Marigliano

{"title":"Effect of UV radiation on postharvest conservation of blueberries","authors":"Eliana Vanesa Campero, Maria Julia Barrionuevo, A. C. G. Marigliano","doi":"10.5155/eurjchem.14.4.473-477.2473","DOIUrl":"https://doi.org/10.5155/eurjchem.14.4.473-477.2473","url":null,"abstract":"The objective of this work is to determine the variation in the nutritional and quality characteristics of blueberries subjected to UV radiation. Blueberries of the variety (JEWEL) provided by Tierra de blueberries, Oran, Monteros, Tucuman were used. The parameters analyzed were variations of the color and content of polyphenols by HPLC and UV-vis. Polyphenols determined by HPLC were: delfinidin-3-galactoside, delfinidine-3-glucoside, cyanidin-3-galactoside, delfinidin-3-arabinoside, cyanidin-3-glucoside, petunidin-3-galactoside, cyanidin-3-arabinoside, petunidin-3-glucoside, peonidin-3-galactoside, petunidin-3-arabinoside, malvidin-3-galactoside and malvidin-3-glucoside. From the results obtained, it is concluded that the polyphenol content varied in the irradiated fruits and in the untreated fruits as a function of time, with the values being closest to the initial time value (control) in the case of irradiated fruits. There were no appreciable differences in color change due to irradiation. At time 0, the color difference in the whole fruit between the treated sample (IFC0) and the standard (NFC0) gave ΔE* values equal to 2.06. After 3 days, the color difference was 3.08 for the natural sample and 6.06 for the treated sample. For this reason, it is considered that irradiation of blueberries is a very appropriate method for conservation, maintaining the nutritional and quality characteristics of blueberries.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"105 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139135071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

In an attempt to add ligands to the sixth (axial) position of vanadyl bis-acetylacetonate: A unique tetranuclear vanadyl species 尝试在双乙酰丙酮酸香草酯的第六个（轴向）位置添加配体：一种独特的四核香草醛物种

European Journal of Chemistry Pub Date : 2023-12-31 DOI: 10.5155/eurjchem.14.4.494-498.2485

R. Lalancette, Ivan Bernal

{"title":"In an attempt to add ligands to the sixth (axial) position of vanadyl bis-acetylacetonate: A unique tetranuclear vanadyl species","authors":"R. Lalancette, Ivan Bernal","doi":"10.5155/eurjchem.14.4.494-498.2485","DOIUrl":"https://doi.org/10.5155/eurjchem.14.4.494-498.2485","url":null,"abstract":"We have explored the interaction of [(acac)2V=O] (acac = acetylacetone) with a series of potential ligands which were chosen because of their expected ability to attach themselves onto its sixth (axial) position. Furthermore, some of the species chosen were expected to have the capability of linking pairs of [(acac)2V=O] molecules, thus creating magnetically coupled substances whose behavior would be interesting to document by magnetic as well as structural methods. Some of the synthetic results were surprising in that unexpected products were obtained which we had not envisioned; specifically, herein we describe a tetranuclear vanadyl cluster (Crystal data for C38H51N4O17ClV4: orthorhombic, space group Pca21 (no. 29), a = 26.4698(3) Å, b = 13.5167(2) Å, c = 12.7659(2) Å, V = 4567.44(11) Å3, Z = 4, μ(CuKα) = 7.842 mm-1, Dcalc = 1.53 g/cm3, 41277 reflections measured (6.538° ≤ 2Θ ≤ 137.892°), 7841 unique (Rint = 0.0428, Rsigma = 0.0421) which were used in all calculations; the final R1 was 0.0675 (I > 2σ(I)) and wR2 was 0.1641 (all data)), which is unusual in several aspects of its composition as well as its stereochemistry.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"49 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139131139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synthesis of calcium propionate from indigenous limestone from Swat area in Pakistan 利用巴基斯坦斯瓦特地区的本土石灰石合成丙酸钙

European Journal of Chemistry Pub Date : 2023-12-31 DOI: 10.5155/eurjchem.14.4.460-465.2456

Ansar Mahmood, S. Zahra, Rashid Mahmood, Asma Sheikh

引用次数: 0

Toxicological aspects of wastewater 废水的毒理学方面

European Journal of Chemistry Pub Date : 2023-12-31 DOI: 10.5155/eurjchem.14.4.451-459.2459

F. Ondrasik, Š. Kročová

{"title":"Toxicological aspects of wastewater","authors":"F. Ondrasik, Š. Kročová","doi":"10.5155/eurjchem.14.4.451-459.2459","DOIUrl":"https://doi.org/10.5155/eurjchem.14.4.451-459.2459","url":null,"abstract":"‘Alea iacta est', the die is cast, said the Roman general Gaius Julius Caesar the moment he and his troops crossed the Rubicon River. This phrase refers to a state where everything has already been decided and this decision cannot be taken back. It is at this borderline that humanity now finds itself; its survival is at stake. The basic biogenic components of the environment, such as water, air, and soil, are coming under the pressure of the modern industrial revolution. The products of this anthropogenic activity significantly affect the environment. We live in a time of rapid climate change, melting of glaciers, devastation of nature, mass extermination, or loss of animal and plant species in order to increase human living standards. Man has caused all this in one stage of human life, a generation. Humanity mismanages natural resources and clings to a lifestyle that is vain. It destroys the natural environment on which it is dependent simultaneously. An environmental disaster is coming. Will our blue planet still be livable for future generations? The study deals with one of the components of the environmental environment, not an insignificant one, that is, water. For the moment, recycled water is a neglected and underappreciated resource from the point of view of the Czech Republic and its state authorities. The cleaning process may be inadequate or unreliable, and residual biological and chemical contaminants may pose a risk to human health. This work focuses on the use of purified wastewater mainly for firefighting unit activities in relation to a possible health risk. The result of the study is a clear possible recommendation for the use of recycled wastewater from a technical, technological, and logistical point of view, but taking into account the precautionary principle.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"54 26","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139130677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hydrothermally synthesized (N,O)-linked Cu(II)-based coordination complex as a potential antibacterial agent 作为潜在抗菌剂的水热合成 (N,O)-linked Cu(II) 配位配合物

European Journal of Chemistry Pub Date : 2023-12-31 DOI: 10.5155/eurjchem.14.4.429-438.2465

Anmol Chettri, Sudarshan Pradhan, Pritika Gurung, Sriparna Roy, Biswajit Sinha

{"title":"Hydrothermally synthesized (N,O)-linked Cu(II)-based coordination complex as a potential antibacterial agent","authors":"Anmol Chettri, Sudarshan Pradhan, Pritika Gurung, Sriparna Roy, Biswajit Sinha","doi":"10.5155/eurjchem.14.4.429-438.2465","DOIUrl":"https://doi.org/10.5155/eurjchem.14.4.429-438.2465","url":null,"abstract":"The N,O-linked Cu(II)-based coordination complex was synthesized hydrothermally and characterized by SC-XRD, FTIR spectroscopy, and FE-SEM. Single crystal X-ray diffraction studies showed that the complex crystallizes in a square pyramidal geometry and belongs to the monoclinic crystal system with the space group P21/n. Crystal data for C14H13CuN3O6: a = 8.7355(11) Å, b = 17.646(2) Å, c = 9.8036(12) Å, β = 98.506(6)°, V = 1494.6(3) Å3, Z = 4, μ(MoKα) = 1.500 mm-1, Dcalc = 1.701 g/cm3, 5120 reflections measured (4.616° ≤ 2Θ ≤ 49.982°), 1953 unique (Rint = 0.0316, Rsigma = 0.0718) which were used in all calculations. The final R1 was 0.0380 (I > 2σ(I)) and wR2 was 0.0972 (all data). The experimental antibacterial activity studies performed using the disc diffusion method revealed that the complex is indeed acting as a good antibacterial agent against Staphylococcus aureus and Escherichia coli. A better understanding of the binding mechanisms was uncovered through comparative molecular docking investigations. The docking score for the target S. aureus glyrase complex with DNA (PDB id-2XCS) was found to be -7.1 kcal/mol, while the docking score for dialkylglycine decarboxylase (PDB id-1D7U) was -5.2 kcal/mol. The high docking score of the complex with the target protein allowed the complex to act as a potential antibacterial agent. These results were also supported by other theoretical studies such as DFT calculations and pharmacokinetic studies. The correlation between the HOMO-LUMO energy gap and antibacterial activity was studied computationally. Hirshfeld surface analysis and pharmacokinetic studies were also performed for this crystal for a better understanding of the intermolecular interactions and ADME properties.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"97 37","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139131528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation of Coulomb integrals with various energy operators to estimate the correlation energy in electronic structure calculations for molecules 用各种能量算子评估库仑积分，以估算分子电子结构计算中的相关能

European Journal of Chemistry Pub Date : 2023-12-31 DOI: 10.5155/eurjchem.14.4.486-493.2480

S. Kristyán

{"title":"Evaluation of Coulomb integrals with various energy operators to estimate the correlation energy in electronic structure calculations for molecules","authors":"S. Kristyán","doi":"10.5155/eurjchem.14.4.486-493.2480","DOIUrl":"https://doi.org/10.5155/eurjchem.14.4.486-493.2480","url":null,"abstract":"Using energy operators RC1-nRD1-m, RC1-nr12-m, and r12-nr13-m with small (n, m) values is fundamental in electronic structure calculations. Analytical integrations of the cases (n, m) = (1, 0) and (0, 1) are based on the Laplace transformation with the integrand exp(-a2t2), the other cases are based on the Laplace transformation with the integrand exp(-a2t) and the two-dimensional version of the Boys function. These analytic expressions, with Gaussian function integrands, are useful for manipulation with higher moments of interelectronic distances, for example, in correlation calculations. The equations derived help to evaluate the one-, two-, and three-electron Coulomb integrals, òρ(1)RC1-nRD1-mdr1, òρ(1)ρ(2)RC1-nr12-mdr1dr2, and òρ(1)ρ(2)ρ(3)r12-nr13-mdr1dr2dr3, wherein ρ(i) is the one-electron density describing the electron clouds in molecules, solids, or any media or ensemble of materials. Analytical solutions to integrals are more useful than numeric solutions; however, the former is not available in many cases. We evaluate these integrals numerically, even more so, the òf(ρ(1))dr1 to òf(ρ(1),ρ(2),ρ(3))dr1dr2dr3 with the analytical function f. For this task, the commonly used density functional theory numerical integration scheme has been elaborated to 6 and 9 dimensions via Descartes product. More importantly, this numerical integration scheme works not only for Gaussian type but also for Slaterian types. Analogy is commented on in terms of the powerful empirical correction between quantum potential energy correction and the empirically corrected Newton’s universal law of gravity in the explanation of dark matter and energy, as well as its relation to Hartree-Fock and Kohn-Sham formalisms.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"124 39","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139134814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Isotopic study of rainfall and definition of local meteoric water lines: Case of the rainfall stations of the city of Bangui in Central African Republic 降雨同位素研究和当地流星水线的定义：中非共和国班吉市雨量站案例

European Journal of Chemistry Pub Date : 2023-12-31 DOI: 10.5155/eurjchem.14.4.445-450.2445

Eric Foto, O. Allahdin, Olga Biteman, N. Poumaye

{"title":"Isotopic study of rainfall and definition of local meteoric water lines: Case of the rainfall stations of the city of Bangui in Central African Republic","authors":"Eric Foto, O. Allahdin, Olga Biteman, N. Poumaye","doi":"10.5155/eurjchem.14.4.445-450.2445","DOIUrl":"https://doi.org/10.5155/eurjchem.14.4.445-450.2445","url":null,"abstract":"The study of the isotopic composition of rainwater discussed in this article allows isotopic characterization of rainfall recorded in the Bangui region over 11 years at two stations. It will highlight the relationships between isotopes, climatic parameters, and temporal variation before defining the local meteoric line, which constitutes the reference point for the region. The results obtained after a follow-up of eleven years without interruption showed two major physical effects, the effect of the rainfall influences more strongly the composition in isotopes, the contents in isotopes vary inversely with the precipitation. For example, heavy rainfall in August and September saw a strong depletion of δ¹⁸O and δ²H contents. These values reach up to -4.96‰ for δ¹⁸O and -28.3‰ for δ²H. Similar, although weaker, effects are observed for July and October precipitation. We also note that the isotope contents at the Bangui University station are lower than those measured at the Bangui Sodeca station located at 386 m altitude on the Lower Ubangi Hill, which is similar to a pseudo-altitude effect. The evolution of stable isotope content in water as a function of meteorological parameters (temperature, rainfall, altitude) has allowed us to determine a local meteorological line for the city of Bangui from two measuring stations defined as follows: δ2H = 7.6 × δ18O + 10.4 (R2 = 0.9909) Université de Bangui, δ2H = 8.4 × δ18O + 12.5 (R2 = 0.9909) Bangui-Sodeca and δ2H = 7.9 × δ18O + 11.3 (R2 = 0.9939) Bangui local meteoric water lines.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"113 35","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139135429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Modification and characterization of selected Zambian clays for potential use as photocatalysts 赞比亚粘土用作光催化剂的改性和表征

European Journal of Chemistry Pub Date : 2023-09-30 DOI: 10.5155/eurjchem.14.3.362-369.2451

Mary Mambwe, Kennedy Kabaso Kalebaila, Todd Johnson, John Moma

{"title":"Modification and characterization of selected Zambian clays for potential use as photocatalysts","authors":"Mary Mambwe, Kennedy Kabaso Kalebaila, Todd Johnson, John Moma","doi":"10.5155/eurjchem.14.3.362-369.2451","DOIUrl":"https://doi.org/10.5155/eurjchem.14.3.362-369.2451","url":null,"abstract":"Natural materials such as clay are valued for their favorable physical and chemical characteristics on the surface. In this study, the selected Zambian clay materials are immobilized with TiO2 and manganese ions to determine their suitability for use as photocatalysts. SiO2 and Al2O3 oxide composition of Zambian clays was obtained in the range of 35.08-52.63/35.15-52.72 and 13.85-21.73/13.77-21.80, respectively, by inductively coupled plasma (ICP) and X-ray fluorescence (XRF); while Energy dispersive spectroscopy (EDS) of modified clays showed that they have 1.54% incorporation of Ti and 4.98% Mn for Chingola clay to act as UV-Vis absorbers. According to the powder X-ray diffraction analysis of raw clays, the primary phase of all samples is quartz and contains low concentrations of bentonite and kaolinite. The scanning electron microscope (SEM) showed fluffy morphology with agglomeration, while the particle sizes of the clay photocatalysts with the use of transmission electron microscopy (TEM) ranged between 3.0 and 4.8 nm. UV-vis spectroscopy of the samples showed bandgap energies ranging from 2.52-3.08 eV. The surface areas, pore volumes, and pore sizes of the investigated modified and unmodified clays determined by the Brunauer, Teller, Emmett/Barrett Joyner Halenda (BET/BJH) model ranged from 12.06-64.51 m2/g, 0.029-0.068 cm3/g, and 0.642-2.802 nm, respectively. To enhance the mixing of oil and clay, the adsorbents were grafted with silane and confirmed by Fourier transform infrared (FTIR) spectroscopy through CH peaks at ~1450 and ~2860 cm-1. The modified clay materials exhibited favorable properties for use as photocatalysts.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136342121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0