Monatshefte Fur Chemie最新文献_第6页

Effect of surface vacancies on the adsorption of Pd and Pb on MgO(100). 表面空位对MgO吸附Pd和Pb的影响

IF 1.8 4区化学

Monatshefte Fur Chemie Pub Date : 2018-01-01 Epub Date: 2018-02-13 DOI: 10.1007/s00706-018-2159-1

Piotr Matczak

{"title":"Effect of surface vacancies on the adsorption of Pd and Pb on MgO(100).","authors":"Piotr Matczak","doi":"10.1007/s00706-018-2159-1","DOIUrl":"https://doi.org/10.1007/s00706-018-2159-1","url":null,"abstract":"Abstract: Theoretical quantum mechanical calculations have been carried out to establish the effect of surface vacancies on the adsorption of Pd and Pb atoms on the defective MgO(100) surface. The investigated defects included neutral, singly and doubly charged O and Mg vacancies on the (100) surface of MgO. These vacancies played the role of Fsn+ and Vsn- (n = 0, 1, 2) adsorption centers for a single Pd or Pb atom. From the results of calculations, it is clear that the Pd- and Pb-atom adsorption at the Fsn+ and Vsn- centers shows different characteristics than at the regular O2- and Mg2+ centers. Drastic changes in geometric, energetic, and electronic parameters are evident in Pd/Vsn- and Pb/Vsn-. The effect of Fs0 and Fs+, which in practice are the most important vacancies, is smaller, yet the adsorption of Pd and Pb at these centers is more energetically favorable than at the regular O2- center. Of the two metals studied, the atom of Pd is bound by the Fs0 and Fs+ centers with higher adsorption energies.Graphical abstract: ","PeriodicalId":18766,"journal":{"name":"Monatshefte Fur Chemie","volume":"149 6","pages":"1009-1015"},"PeriodicalIF":1.8,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00706-018-2159-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36209713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Identification of a biliverdin geometric isomer by means of HPLC/ESI-MS and NMR spectroscopy. Differentiation of the isomers by using fragmentation "in-source". 通过 HPLC/ESI-MS 和 NMR 光谱鉴定胆绿素几何异构体。利用 "源内 "碎片对异构体进行区分。

IF 1.8 4区化学

Monatshefte Fur Chemie Pub Date : 2018-01-01 Epub Date: 2018-02-13 DOI: 10.1007/s00706-018-2161-7

Rafał Frański, Błażej Gierczyk, Łukasz Popenda, Małgorzata Kasperkowiak, Tomasz Pędzinski

引用次数: 0

Application of X-ray powder diffraction and differential scanning calorimetry for identification of counterfeit drugs. x射线粉末衍射和差示扫描量热法在假药鉴别中的应用。

IF 1.8 4区化学

Monatshefte Fur Chemie Pub Date : 2018-01-01 Epub Date: 2018-04-10 DOI: 10.1007/s00706-018-2193-z

Izabela Jendrzejewska, Paweł Zajdel, Ewa Pietrasik, Zoja Barsova, Tomasz Goryczka

{"title":"Application of X-ray powder diffraction and differential scanning calorimetry for identification of counterfeit drugs.","authors":"Izabela Jendrzejewska, Paweł Zajdel, Ewa Pietrasik, Zoja Barsova, Tomasz Goryczka","doi":"10.1007/s00706-018-2193-z","DOIUrl":"https://doi.org/10.1007/s00706-018-2193-z","url":null,"abstract":"Abstract: X-ray analysis confirmed that in all investigated samples, the active API (acetylsalicylic acid and ascorbic acid) was present. The values of the interplanar distance dhkl for the studied samples are in good accordance with those presented in the ICDD database. The intensities of the diffraction lines depend on the content of the component in the tested preparation. Therefore, different intensities of lines for the APIs were observed in the obtained diffraction patterns. Thermal analysis of the studied substances showed that during the thermal analysis, the following phenomena might occur: dehydration and (or) melting, crystalline transformation. Moreover, it was found that the chemical structure of the studied compounds affects the process of their thermal decomposition. The data obtained during these investigations can be useful in quick tests of physicochemical discrepancies and abnormalities between potential components of pharmaceutical preparations. The evidence for the interaction can be obtained by comparing DSC and TG curves of the drug and the excipient, as well as those of their physical mixtures. For this reason, the study of characteristics of thermal decomposition of drugs and excipients is necessary. Based on the above investigations, it may be stated that a combination of two methods: XRPD and DSC can be used to distinguish the original drugs from counterfeit products, e.g., by checking for the presence of the correct API or by a comparison of the drugs fingerprint.Graphical abstract: ","PeriodicalId":18766,"journal":{"name":"Monatshefte Fur Chemie","volume":"149 5","pages":"977-985"},"PeriodicalIF":1.8,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00706-018-2193-z","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36064559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

A new method for real-time monitoring of volatiles in frying fumes using proton transfer reaction mass spectrometry with time-of-flight analyser. 基于飞行时间分析仪的质子转移反应质谱法实时监测煎炸烟气中挥发物。

IF 1.8 4区化学

Monatshefte Fur Chemie Pub Date : 2018-01-01 Epub Date: 2018-08-10 DOI: 10.1007/s00706-018-2217-8

Tomasz Majchrzak, Wojciech Wojnowski, Tomasz Dymerski, Jacek Gębicki, Jacek Namieśnik

{"title":"A new method for real-time monitoring of volatiles in frying fumes using proton transfer reaction mass spectrometry with time-of-flight analyser.","authors":"Tomasz Majchrzak, Wojciech Wojnowski, Tomasz Dymerski, Jacek Gębicki, Jacek Namieśnik","doi":"10.1007/s00706-018-2217-8","DOIUrl":"https://doi.org/10.1007/s00706-018-2217-8","url":null,"abstract":"Abstract: To safeguard the consumers' well-being, it is necessary to develop novel methods for determination of carcinogens in food, including volatiles generated during frying. The currently used procedures for analysis of volatile fraction of vegetable oils are not based on real-time measurements and thus do not enable the determination of carcinogenic compounds in frying fumes; instead, only the headspace or liquid fraction is sampled. In this article, described is an approach in which proton transfer reaction mass spectrometry with time-of-flight analyser (PTR-TOFMS) was used for real-time monitoring of carcinogenic compounds generated during thermal degradation of rapeseed oil. Using PTR-MS, it was possible to monitor the concentration of known volatile carcinogens according to the International Agency for Research on Cancer (IARC), alongside BTEX compounds, acrolein, and selected aldehydes. Moreover, the applicability of several supervised data analysis methods for the classification of oil samples according to their degree of thermal degradation was presented, with best results obtained using the k-nearest neighbours algorithm. Proton transfer reaction mass spectrometry is a powerful technique for the determination of carcinogenic compounds generated during thermal degradation of edible oils. Further investigation of the chemical processes which occur during frying can lead to improvement of food safety.Graphical abstract: ","PeriodicalId":18766,"journal":{"name":"Monatshefte Fur Chemie","volume":"149 9","pages":"1549-1554"},"PeriodicalIF":1.8,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00706-018-2217-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36455422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

The use of RP-HPLC-Q-TOF-MS as a powerful tool for wastewater composition profiling and selection of water pollution marker specific to wastewater contamination. 利用反相高效液相色谱- q - tof - ms作为分析废水成分和选择废水污染标志物的有力工具。

IF 1.8 4区化学

Monatshefte Fur Chemie Pub Date : 2018-01-01 Epub Date: 2018-08-09 DOI: 10.1007/s00706-018-2259-y

Dagmara Kempińska, Agata Kot-Wasik

{"title":"The use of RP-HPLC-Q-TOF-MS as a powerful tool for wastewater composition profiling and selection of water pollution marker specific to wastewater contamination.","authors":"Dagmara Kempińska, Agata Kot-Wasik","doi":"10.1007/s00706-018-2259-y","DOIUrl":"https://doi.org/10.1007/s00706-018-2259-y","url":null,"abstract":"Abstract: Limited drinking water resources and water pollution are one of the main worldwide problems. To reduce the consumption of fresh water resources, the use of treated wastewater has been proposed. The farmlands have been irrigated with wastewater for centuries, but the composition of used sewage has changed over the years. Recent research has revealed the presence of hundreds of new organic contaminants in many environmental waters, including wastewaters and their receivers. For this reason, wastewater profiling and monitoring are of high importance and urgent need. In this study, the HPLC-Q-TOF-MS has been used for the profiling of wastewater composition and evaluation of the water pollution markers belonging to emerging contaminants. Three different solid-phase extraction approaches were applied to obtain the best results. Compounds such as acesulfame-K, caffeine, carbamazepine, cyclamate, ibuprofen, methyl paraben, paracetamol, or saccharin were detected in raw wastewater samples, whereas only acesulfame-K, carbamazepine, and sucralose were found in effluent samples. It seems that these particular compounds might be chosen as water pollution marker specific to Polish communal sewages.Graphical abstract: ","PeriodicalId":18766,"journal":{"name":"Monatshefte Fur Chemie","volume":"149 9","pages":"1595-1604"},"PeriodicalIF":1.8,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00706-018-2259-y","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36455425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Insights in the determination of saxitoxin with fluorogenic crown ethers in water. 用含氟冠醚测定水中沙司毒素的启示。

IF 1.8 4区化学

Monatshefte Fur Chemie Pub Date : 2018-01-01 Epub Date: 2018-01-11 DOI: 10.1007/s00706-017-2074-x

Bernhard J Müller, Günter Mistlberger, Ingo Klimant

引用次数: 0

Analytical and legislative challenges of sewage sludge processing and management. 污水污泥处理和管理的分析和立法挑战。

IF 1.8 4区化学

Monatshefte Fur Chemie Pub Date : 2018-01-01 Epub Date: 2018-08-09 DOI: 10.1007/s00706-018-2255-2

Bartłomiej Michał Cieślik, Lesław Świerczek, Piotr Konieczka

{"title":"Analytical and legislative challenges of sewage sludge processing and management.","authors":"Bartłomiej Michał Cieślik, Lesław Świerczek, Piotr Konieczka","doi":"10.1007/s00706-018-2255-2","DOIUrl":"10.1007/s00706-018-2255-2","url":null,"abstract":"Abstract: This article presents the most popular methods of sewage sludge management and analytical techniques which could be a powerful tool in designing new sewage sludge management methods. Chemical analysis is also described as a vital point at the subsequent stages of technological processes control and sewage sludge quality assessment. It is also an instrument essential to maintaining control of processed sewage sludge introduced to the environment as ready-to-use materials. The sludge management method is conditioned by the compliance with legal acts concerning sludge management. The most important of these contain information regarding allowable concentrations of pollutants which can be released into the environment, and the most important declarations concerning sewage sludge management. Various analytical techniques and preparation methods that can be used during the monitoring of the managed and processed sewage sludge are described. The most important are chromatographic techniques, methods based on inductively coupled plasma, and mass spectrometry based methods.Graphical abstract: ","PeriodicalId":18766,"journal":{"name":"Monatshefte Fur Chemie","volume":"149 9","pages":"1635-1645"},"PeriodicalIF":1.8,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00706-018-2255-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36453512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Novel analytical method for detection of orange juice adulteration based on ultra-fast gas chromatography. 基于超快速气相色谱法检测橙汁掺假的新型分析方法。

IF 1.8 4区化学

Monatshefte Fur Chemie Pub Date : 2018-01-01 Epub Date: 2018-08-09 DOI: 10.1007/s00706-018-2233-8

Anna Różańska, Tomasz Dymerski, Jacek Namieśnik

{"title":"Novel analytical method for detection of orange juice adulteration based on ultra-fast gas chromatography.","authors":"Anna Różańska, Tomasz Dymerski, Jacek Namieśnik","doi":"10.1007/s00706-018-2233-8","DOIUrl":"10.1007/s00706-018-2233-8","url":null,"abstract":"Abstract: The food authenticity assessment is an increasingly important issue in food quality and safety. The application of an electronic nose based on ultra-fast gas chromatography technique enables rapid analysis of the volatile compounds from food samples. Due to the fact that this technique provides chemical profiling of natural products, it can be a powerful tool for authentication in combination with chemometrics. In this article, a methodology for classification of Not From Concentrate (NFC) juices was presented. During research samples of 100% orange juice, 100% apple juice, as well as mixtures of these juices with known percentage of base juices were tested. Classification of juice samples was carried out using unsupervised and supervised statistical methods. As chemometric methods, Hierarchical Cluster Analysis, Classification Tree, Naïve Bayes, Neural Network, and Random Forest classifiers were used. The ultra-fast GC technique coupled with supervised statistical methods allowed to distinguish juice samples containing only 1.0% of impurities. The developed methodology is a promising analytical tool to ensure the authenticity and good quality of juices.Graphical abstract: ","PeriodicalId":18766,"journal":{"name":"Monatshefte Fur Chemie","volume":"149 9","pages":"1615-1621"},"PeriodicalIF":1.8,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6105224/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36455427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stepwise photosensitized thymine dimerization mediated by an exciton intermediate. 由激子中间体介导的逐步光敏胸腺二聚化。

IF 1.8 4区化学

Monatshefte Fur Chemie Pub Date : 2018-01-01 Epub Date: 2017-12-04 DOI: 10.1007/s00706-017-2108-4

Clemens Rauer, Juan J Nogueira, Philipp Marquetand, Leticia González

{"title":"Stepwise photosensitized thymine dimerization mediated by an exciton intermediate.","authors":"Clemens Rauer, Juan J Nogueira, Philipp Marquetand, Leticia González","doi":"10.1007/s00706-017-2108-4","DOIUrl":"10.1007/s00706-017-2108-4","url":null,"abstract":"Abstract: Cyclobutane thymine dimerization is the most prominent DNA photoinduced damage. While the ultrafast mechanism that proceeds in the singlet manifold is nowadays well established, the triplet-state pathway is not completely understood. Here we report the underlying mechanism of the photosensitized dimerization process in the triplet state. Quantum chemical calculations, combined with wavefunction analysis, and nonadiabatic molecular dynamics simulations demonstrate that this is a stepwise reaction, traversing a long-lived triplet biradical intermediate, which is characterized as a Frenkel exciton with very small charge-transfer character. The low yield of the reaction is regulated by two factors: (i) a relatively large energy barrier that needs to be overcome to form the exciton intermediate, and (ii) a bifurcation of the ground-state potential-energy surface that mostly leads back to the Franck-Condon region because dimerization requires a very restricted combination of coordinates and velocities at the event of non-radiative decay to the ground state.Graphical abstract: ","PeriodicalId":18766,"journal":{"name":"Monatshefte Fur Chemie","volume":"149 1","pages":"1-9"},"PeriodicalIF":1.8,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00706-017-2108-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"35699348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13

Monitoring of n-butanol vapors biofiltration process using an electronic nose combined with calibration models. 结合校正模型的电子鼻监测正丁醇蒸气生物过滤过程。

IF 1.8 4区化学

Monatshefte Fur Chemie Pub Date : 2018-01-01 Epub Date: 2018-08-10 DOI: 10.1007/s00706-018-2243-6

Bartosz Szulczyński, Piotr Rybarczyk, Jacek Gębicki

引用次数: 17