Chemia Naissensis最新文献_第6页

The Influence of Metal Microelements, Colloids and Organic Phase on Physical-chemical Properties and Processes in Peloids 金属微量元素、胶体和有机相对类质体理化性质和过程的影响

Chemia Naissensis Pub Date : 1900-01-01 DOI: 10.46793/chemn4.1.18p

J. Purenovic, M. Purenović, M. Ranđelović

{"title":"The Influence of Metal Microelements, Colloids and Organic Phase on Physical-chemical Properties and Processes in Peloids","authors":"J. Purenovic, M. Purenović, M. Ranđelović","doi":"10.46793/chemn4.1.18p","DOIUrl":"https://doi.org/10.46793/chemn4.1.18p","url":null,"abstract":"The main emphasis in this study was on the modification of peloid characteristics through maturation processes, physical-chemical analysis of salty geothermal water and intact geomaterial, content of toxic heavy metals, radionuclides, and microorganisms in matured peloid, and physical-chemical processes that occur in a highly heterogeneous and microheterogeneous system solid-water. Main processes were considered to be mass transfer, colloidal processes, adsorption and surface compounding by macro- and micronutrients from salty mineral water with surface groups of intact geomaterial. This study indicated that inorganic and organic components of peloid could be in the form of colloids, suspended macro- and microparticles, ions and molecules. Colloidal silica had special importance in peloids. Due to low maximum solubility of silica, there were a number of processes in which coagulated and floculated particles were created during maturation, especially in the presence of metal cations (e.g., Fe3+ and Al3+) and colloidal metal hydroxides which noticeably reduced the solubility of silica. Single charged alkali metal cations caused coagulation of colloidal silica occupying bridging positions between negatively charged colloidal particles. Colloidal silica in peloid together with other micro- and macro phases, and with the help of numerous microelements, comes in interaction, building a complex surface and occluded compounds. In the multiphase system, very complex organic and inorganic compunds are formed, which are important for therapeutic purposes.","PeriodicalId":351621,"journal":{"name":"Chemia Naissensis","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130147208","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

Alternative Periodic System of the Elements 元素的交替周期系统

Chemia Naissensis Pub Date : 1900-01-01 DOI: 10.46793/chemn4.1.01k

D. Kostić, N. Krstic, Marina Blagojević

引用次数: 0

Molecular dynamics simulations of ASC09, ritonavir, lopinavir and darunavir with the COVID-19 protease ASC09、利托那韦、洛匹那韦和达那韦与COVID-19蛋白酶的分子动力学模拟

Chemia Naissensis Pub Date : 1900-01-01 DOI: 10.46793/chemn3.1.155i

B. Ilić

{"title":"Molecular dynamics simulations of ASC09, ritonavir, lopinavir and darunavir with the COVID-19 protease","authors":"B. Ilić","doi":"10.46793/chemn3.1.155i","DOIUrl":"https://doi.org/10.46793/chemn3.1.155i","url":null,"abstract":"Given the novelty of SARS-CoV-2 infection (COVID-19), and the lack of proven therapies, a wide variety of strategies are being employed to combat COVID-19 pandemic. Many of these emerging strategies rely on repurposing existing drugs and their mechanistic approaches that are effective against either similar viral infections or the serious symptoms that are caused by COVID-19. The recently solved issue of the crystal structure of the COVID-19 protease has made elucidating the structure–activity relationship feasible. The interaction of ASC09, ritonavir, lopinavir and darunavir with COVID-19 protease was simulated using the Site Finder module, molecular docking and molecular dynamics (MD). Analysis of the MD trajectories has provided the ligand/receptor interaction fingerprints, combining information on the crucial receptor residues and frequency of the ligand/residue contacts. The contact frequencies and the contact maps suggest that for all studied antiviral drugs, the interactions with Gln 107, Pro 108, Gln 110 and His 246 are an important factor for drugs affinities toward the COVID-19 protease. However, the leading interactions with Arg 105, Phe 134, Glu 240, Thr 243, Asp 245 or Phe 294 also significantly contribute to the ligand/receptor interplay and, in particular, differentiate their binding affinities toward COVID-19 protease.","PeriodicalId":351621,"journal":{"name":"Chemia Naissensis","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116450627","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

Recent developments in sorbent based water samples treatments prior GC-MS analysis of polycyclic aromatic hydrocarbons 多环芳烃GC-MS分析前的吸附水样处理研究进展

Chemia Naissensis Pub Date : 1900-01-01 DOI: 10.46793/chemn1.1.093c

Slobodan A. Ćirić, V. Mitić, J. Nikolić, M. Ilic, M. Dimitrijević, S. Simonović, V. S. Stankov Jovanović

{"title":"Recent developments in sorbent based water samples treatments prior GC-MS analysis of polycyclic aromatic hydrocarbons","authors":"Slobodan A. Ćirić, V. Mitić, J. Nikolić, M. Ilic, M. Dimitrijević, S. Simonović, V. S. Stankov Jovanović","doi":"10.46793/chemn1.1.093c","DOIUrl":"https://doi.org/10.46793/chemn1.1.093c","url":null,"abstract":"Polycyclic aromatic hydrocarbons (PAHs) are omnipresent contaminants of the environment, with evidenced harmful effects to human health. Especially endangered are waters, which may affect biota directly or by enabling transport through all environmental compartments. Therefore, constant monitoring of PAHs content in waters is of essential importance. Before most of the analysis, sample preparation is compulsory. Conventional extraction techniques are often time and reagents consuming and not following the rules of “green analytical chemistry”. Thus, miniaturization of classic extraction methods is of high importance to reduce solvent volumes, waste, time of treatment and cost. Recent sample preparation techniques, such as solid phase extraction (SPE), microextraction by packed sorbent (MEPS), solid phase microextraction (SPME), stir bar sorptive extraction (SBSE), dispersive solid phase extraction (dSPE) and dispersive micro-solid phase extraction (D-µ-SPE) were proven as suitable for the extraction of polycyclic aromatic hydrocarbons (PAHs) from water samples and their determination by gas chromatography-mass spectrometry. These sample pretreatments are following “green chemistry” principles, offering the simplicity of operation, reducing costs and time of preparation, without compromising the general analytical parameters of the applied analytical method.","PeriodicalId":351621,"journal":{"name":"Chemia Naissensis","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129364061","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

Nickel(II) interactions with chlorophylls in solution: impact to degradation induced by UV-irradiation 镍(II)与溶液中叶绿素的相互作用:对紫外线照射诱导的降解的影响

Chemia Naissensis Pub Date : 1900-01-01 DOI: 10.46793/chemn5.2.01z

J. Zvezdanović, S. Petrović, Aleksandar Lazarević

{"title":"Nickel(II) interactions with chlorophylls in solution: impact to degradation induced by UV-irradiation","authors":"J. Zvezdanović, S. Petrović, Aleksandar Lazarević","doi":"10.46793/chemn5.2.01z","DOIUrl":"https://doi.org/10.46793/chemn5.2.01z","url":null,"abstract":"Chlorophylls and metal substituted complexes of chlorophylls with known photosensitizing abilities can be used in many types of biological and solar energy applications; thus, it is important to analyze their basic properties when they are treated by visible light and/or UV radiation. Nickel(II) can replace central magnesium from chlorophyll (Chl) molecule to form a metal substituted, “central” Ni-Chl complex. So, the possible formation of nickel-chlorophyll complexes in 95% ethanol at 40 °C was studied by UHPLC-DAD chromatography (UltraHigh Performance Liquid Chromatography–Diode Array Detector). Nickel(II)-chlorophylls interactions in the reaction solutions at 40 °C lead not only to the formation of the Ni-related Chls, Ni-Chl complexes but several oxidation and demetalation products of chlorophylls. On the other hand, the influence of nickel(II) – chlorophyll interactions on chlorophylls solutions stability under continual UV-A, -B, and -C irradiation in 95% ethanol, was followed by UV-Vis spectrophotometry. Chlorophylls as well as their reaction solutions with nickel(II) undergo photochemical degradation obeying first- order kinetics. In general, the degradation is “energy-dependent”, i.e. proportional to the UV photons energy input. Chlorophylls are less stable than their reaction solutions with nickel(II), probably due to the higher stability of Ni-chlorophylls complexes, to all three subranges of UV- irradiation.","PeriodicalId":351621,"journal":{"name":"Chemia Naissensis","volume":"124 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128425451","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: 1

Development and application of kinetic-spectrophotometric method for analysis of diflubenzuron in soil samples using SPE followed by HPLC method 固相萃取-高效液相色谱动力学分光光度法分析土壤样品中氟虫脲的建立及应用

Chemia Naissensis Pub Date : 1900-01-01 DOI: 10.46793/chemn4.1.40pm

Emilija T. Pecev-Marinković, Ana S. Miletić, A. Pavlović, V. Dekić

{"title":"Development and application of kinetic-spectrophotometric method for analysis of diflubenzuron in soil samples using SPE followed by HPLC method","authors":"Emilija T. Pecev-Marinković, Ana S. Miletić, A. Pavlović, V. Dekić","doi":"10.46793/chemn4.1.40pm","DOIUrl":"https://doi.org/10.46793/chemn4.1.40pm","url":null,"abstract":"The purpose of this paper is to present a new sensitive and simple kinetic-spectrophotometric method for the determination of the insecticide diflubenzuron (DFB). The kinetic method is based on the inhibition effect of DFB on the oxidation of sulfanilic acid (SA) by potassium periodate in acetate buffer in the presence of Fe(III) ion as a catalyst and 1,10-phenantroline. The reaction was monitored spectrophotometrically by measuring the increase in absorbance with time of the reaction product at 368 nm. Diflubenzuron was determined with linear calibration graph in the interval from 0.0374 to 0.374 μg/cm3 and from 0.374 to 26.18 μg/cm3. The detection limit and quantification limit of the method with 3σ criteria were 0.0039 μg/cm3 and 0.0131 μg/cm3, respectively. The relative standard deviations for five replicate determinations of 0.0374, 0.188 and 0.374 μg/cm3 DFB were 2.24, 2.11 and 1.10%, respectively. The method was successfully applied to determine DFB residues in soil samples. Solid-phase extraction (SPE) was used for extraction of DFB from soil and samples with Chromabond® (Macherey-Nagel) C18 cartridges. The HPLC method was used as a comparative method to verify the results. The results obtained by two different methods showed good agreement.","PeriodicalId":351621,"journal":{"name":"Chemia Naissensis","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130682389","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

History of the Periodic System of the Elements 元素周期系统的历史

Chemia Naissensis Pub Date : 1900-01-01 DOI: 10.46793/chemn3.2.117k

D. Kostić, Nenad Krstić, Marina Blagojević

引用次数: 0

In silico study on the apicoplast L4 ribosomal protein and three domains from 23S rRNA from „Plasmodium falciparum“ and comparison with the existing cocrystal structures “恶性疟原虫”顶质体L4核糖体蛋白和23S rRNA三个结构域的计算机研究，并与现有共晶结构比较

Chemia Naissensis Pub Date : 1900-01-01 DOI: 10.46793/chemn2.2.050a

B. Arsić, J. Barber

引用次数: 1

Protein amino acids as a complete (periodic) system 蛋白质氨基酸作为一个完整的(周期性的)系统

Chemia Naissensis Pub Date : 1900-01-01 DOI: 10.46793/chemn2.1.001r

Miloje M. Rakocevic

引用次数: 3