IF 0.6 4区化学

Chemija Pub Date : 2023-07-05 DOI: 10.6001/chemija.2023.34.2.4

T. Petrulionienė, T. Murauskas, Mantas Norkus, E. Naujalis

{"title":"Emission of additives and degradation products from commercial polypropylene, polyethylene and their composite packages","authors":"T. Petrulionienė, T. Murauskas, Mantas Norkus, E. Naujalis","doi":"10.6001/chemija.2023.34.2.4","DOIUrl":"https://doi.org/10.6001/chemija.2023.34.2.4","url":null,"abstract":"Migration is a known phenomenon defined as the partitioning of certain chemical compounds from plastic food packaging into food and has been intensely investigated in recent years. Due to outstanding chemical and physical properties plastics are used in many fields. Polypropylene and polyethylene are extensively used polymers because of their chemical resistance, high tensile strength and low density. To improve the properties of the plastics, additives such as plasticizers, stabilizers, antioxidants, lubricants, pigments and others are required to be added. However, they can migrate from the plastics into the food and contaminate it during production or storage. Therefore, the aim of this study was to investigate commercial polypropylene and polyethylene packages to determine what most often used additives and degradation products of the food packages can migrate to food. After the initial identification of plastics by Fourier-transform infrared spectrometry, the determination of cadmium, chromium, lead and mercury was carried out by atomic absorption spectrophotometry. To evaluate possible volatile and semi-volatile organic compounds thermal desorption gas chromatography coupled with mass spectrometry was used. The results revealing the presence of different potential organic compounds and metals emitted during the degradation process of different types of food contact materials are discussed.","PeriodicalId":9720,"journal":{"name":"Chemija","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41511182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation of the qualitative and quantitative composition of amino acids in the herb of smallflowered galinsoga (Galinsoga parviflora L.) using gas chromatography 气相色谱法研究小花加林子(galinsoga parviflora L.)中氨基酸的定性和定量组成

IF 0.6 4区化学

Chemija Pub Date : 2023-07-05 DOI: 10.6001/chemija.2023.34.2.2

Daiva Kazlauskienė, Palma Nenortienė, Deividas Kvedaravičius, J. Daukšienė, S. Velžienė

引用次数: 0

Study of the antifungal effects of quaternary ammonium salt for the preservation of inked paper 季铵盐对水墨纸保鲜的抑菌作用研究

IF 0.6 4区化学

Chemija Pub Date : 2023-07-05 DOI: 10.6001/chemija.2023.34.2.3

Milda Liubinienė, Ugnė Urbaitytė, A. Beganskiene

{"title":"Study of the antifungal effects of quaternary ammonium salt for the preservation of inked paper","authors":"Milda Liubinienė, Ugnė Urbaitytė, A. Beganskiene","doi":"10.6001/chemija.2023.34.2.3","DOIUrl":"https://doi.org/10.6001/chemija.2023.34.2.3","url":null,"abstract":"Biological degradation of documentary heritage is a serious issue faced by libraries, museums and archives as it can lead to paper becoming brittle, fragile and discoloured, resulting in a loss of information. This study investigates the impact of didecyldimethylammonium bromide (DDAB) on the properties of pure or inked paper and the growth of different types of fungi. Three fungi species known for their ability to cause paper biodeterioration in libraries and museums, Aspergillus clavatus Desm, Penicillium paneum Frisvald and Ulocladium chartarum Preuss, were selected for the DDAB salt antifungal activity test. The study measured the pH and degree of polymerization (DP), monitored colour changes and conducted scanning electron microscopy analyses (SEM) to confirm that DDAB can be used as a biocide for fungi on pure or inked paper. The study also investigated the antifungal effect of DDAB on paper treated with different types of ink, including black (iron-gall ink) and brown (copper ink). Didecyldimethylammonium bromide (DDAB) can be used as a biocide for cleaning and preserving paper documents, with active concentrations of 0.7 and 1%.","PeriodicalId":9720,"journal":{"name":"Chemija","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45329485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermodynamic, thermochemical and thermophysical properties of HgBr2 HgBr2的热力学、热化学和热物理性质

IF 0.6 4区化学

Chemija Pub Date : 2023-07-05 DOI: 10.6001/chemija.2023.34.2.1

A. Kozma, A. Malinina, E. Golub, V. Rusyn, N. Golub, Vitalii Dziamko, Viktoriia Dziamko, O. Malinin, A. Solomon

{"title":"Thermodynamic, thermochemical and thermophysical properties of HgBr2","authors":"A. Kozma, A. Malinina, E. Golub, V. Rusyn, N. Golub, Vitalii Dziamko, Viktoriia Dziamko, O. Malinin, A. Solomon","doi":"10.6001/chemija.2023.34.2.1","DOIUrl":"https://doi.org/10.6001/chemija.2023.34.2.1","url":null,"abstract":"For mercury dibromide HgBr2, a promising component of the working mixture of gas-discharge exciplex sources of coherent (lasers) and spontaneous (exciplex lamps) radiation, as well as a promising nonlinear optical crystal for the infrared radiation process, thermodynamic and thermochemical properties in the temperature range 173–512 K were investigated. The established basic thermodynamic (isobaric heat capacity Ср, total entropy S, enthalpy H and Gibbs energy G) and thermochemical (enthalpy ΔHf and Gibbs energy ΔGf of formation) functions of HgBr2 were compared with the known literature data at 298–514 K. The obtained results differed from the literature within 1–2% (for Ср), 0.1–0.2% (for S, H and G) and 0.1–0.6% (for ΔHf and ΔGf). The experimental data, combined with semi-empirical approaches and ab initio calculations taken from the literature, were used to estimate the previously unknown additional thermodynamic and thermophysical properties of HgBr2: isochoric heat capacity CV, Debye temperature θD, volume thermal expansion αV, isothermal compressibility βT (isothermal bulk modulus BT = 1/βT), Grüneisen constant γG, phonon longitudinal vl, transverse vs, average –v velocities and phonon thermal conductivity κ. In the present work, it was found that crystalline mercury dibromide expands strongly upon heating and has a low phonon thermal conductivity.","PeriodicalId":9720,"journal":{"name":"Chemija","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48486812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Formation of tethered bilayer lipid membranes on gold surface probed by in situ SEIRAS 原位SEIRAS探测金表面束缚双层脂质膜的形成

IF 0.6 4区化学

Chemija Pub Date : 2023-04-07 DOI: 10.6001/chemija.2023.34.1.1

Vaidas Pudžaitis, M. Talaikis, G. Valinčius, G. Niaura

{"title":"Formation of tethered bilayer lipid membranes on gold surface probed by in situ SEIRAS","authors":"Vaidas Pudžaitis, M. Talaikis, G. Valinčius, G. Niaura","doi":"10.6001/chemija.2023.34.1.1","DOIUrl":"https://doi.org/10.6001/chemija.2023.34.1.1","url":null,"abstract":"\u0000 \u0000 \u0000 \u0000Tethered bilayer lipid membranes (tBLMs) are versatile platforms for the analysis of biochemical and biophysical processes at biological membranes. To control the stability and functional properties of these artificial constructions, molecular-level knowledge on the organization and structure is required. We used surface-enhanced infrared absorption spectroscopy (SEIRAS) to elucidate the in situ formation of tBLMs on a gold substrate. The alkyl chains of long-chain anchoring thiol in a mixed self-assembled monolayer after 60 min of incubation in an adsorption methanol-d4 solution was found to be in a disordered state. Spectroscopic data revealed the complete formation of a bilayer after 60 min of incubation of a mixed anchoring monolayer in a phosphate buffer solution containing vesicles formed from partially deuterated lipid DPPC-d62 and cholesterol-d7. The temporal evolution of absorption bands from the lipid, anchoring mixed monolayer thiol, and water with increasing the bilayer formation time in the phosphate buffer solution containing vesicles revealed a two-stage process. Firstly, the adsorption of lipid molecules with a simultaneous withdrawal of water takes place at the interface. Secondly, the transformation of alkyl chains of the anchoring monolayer due to the insertion and interaction of lipids with the monolayer proceeds. \u0000 \u0000 \u0000 \u0000","PeriodicalId":9720,"journal":{"name":"Chemija","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42339746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synthesis and investigation of silver-coated monolithic solid phase microextraction silica sorbent 镀银整体固相微萃取二氧化硅吸附剂的合成与研究

IF 0.6 4区化学

Chemija Pub Date : 2023-04-07 DOI: 10.6001/chemija.2023.34.1.5

Gerardas Laurinavičius, Vilius Poškus

引用次数: 0

Three-dimensional Au(NiMo)/Ti catalysts for efficient oxygen evolution reaction 高效析氧反应的三维Au(NiMo)/Ti催化剂

IF 0.6 4区化学

Chemija Pub Date : 2023-04-07 DOI: 10.6001/chemija.2023.34.1.4

Sukomol Barua, A. Balčiūnaitė, J. Vaičiūnienė, L. Tamašauskaitė-Tamašiūnaitė, E. Norkus

引用次数: 0

Thermodynamic and thermochemical properties of Cu3(PO4)2·3H2O Cu3(PO4)2·3H2O的热力学和热化学性质

IF 0.6 4区化学

Chemija Pub Date : 2023-04-07 DOI: 10.6001/chemija.2023.34.1.3

A. Kozma, N. Golub, Yevhenii Golub, V. Sidey, A. Solomon, A. Kuznietsova, Y. Herneshii

{"title":"Thermodynamic and thermochemical properties of Cu3(PO4)2·3H2O","authors":"A. Kozma, N. Golub, Yevhenii Golub, V. Sidey, A. Solomon, A. Kuznietsova, Y. Herneshii","doi":"10.6001/chemija.2023.34.1.3","DOIUrl":"https://doi.org/10.6001/chemija.2023.34.1.3","url":null,"abstract":"\u0000 \u0000 \u0000 \u0000Copper (II) orthophosphate trihydrate Cu3(PO4)2·3H2O has been synthesized by the exchange chemical reactions in aqueous solutions from the compounds Cu(NO3)2·3H2O, NH4OH and H3PO4. The final product has been investigated by using atomic absorption spectroscopy (AAS), infrared spectrometry (IRS), differential thermal analysis (DTA) and X-ray powder diffraction (XRD) techniques. For the first time, the experimental heat capacity Ср° of Cu3(PO4)2·3H2O has been investigated in the temperature range 198‒402 K. Combining the experimental results with the literature data made it possible to determine the thermodynamic and thermochemical properties, such as enthalpy НТ° , entropy SТ° , Gibbs energy GТ° , enthalpy of formation ΔHf°(T), Gibbs energy of formation ΔGf°(T) and logarithm of the equilibrium constant of formation reaction log[Kf°(T)], for the title compound. It was found that at the extreme temperatures of the experiment, Cu3(PO4)2·3H2O has Ср° = 245.96 J·mol–1·K–1, Н° = –3169.59 kJ·mol–1, S° = 311.34 J·mol–1·K–1, G° = –3231.24 kJ·mol–1 (at 198 K); Ср° = 455.31 J·mol–1·K–1, Н° = –3097.93 kJ·mol–1, S° = 551.48 J·mol–1·K–1, G° = –3319.62 kJ·mol–1, ΔHf° = –3138.48 kJ·mol–1, ΔGf° = –2625.39 kJ·mol–1, log[K ] = 341.13 (at 402 K). \u0000 \u0000 \u0000 \u0000","PeriodicalId":9720,"journal":{"name":"Chemija","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48528142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Synthesis, transformation and preliminary bioassay of 3-(thiazol-2-yl(p-tolyl)amino)propanoic acid derivatives 3-（噻唑-2-基（对甲苯基）氨基）丙酸衍生物的合成、转化及初步生物测定

IF 0.6 4区化学

Chemija Pub Date : 2023-04-07 DOI: 10.6001/chemija.2023.34.1.7

Birutė Sapijanskaitė-Banevič, Birutė Grybaitė, R. Vaickelionienė, I. Bružaitė

引用次数: 1

Phenolic content and antioxidant activity in medicinal raw material of introduced Artemisia L. species in Lithuania 立陶宛引种青蒿药用原料的酚类含量及抗氧化活性

IF 0.6 4区化学

Chemija Pub Date : 2023-04-07 DOI: 10.6001/chemija.2023.34.1.6

S. Saunoriūtė, O. Ragažinskienė, L. Raudonė, L. Ivanauskas, M. Marksa

引用次数: 0

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