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排序方式: 共有717条查询结果,搜索用时 15 毫秒
711.
Giuseppe Sammarco Chiara Dall'Asta Michele Suman 《Journal of mass spectrometry : JMS》2023,58(10):e4954
Geographical provenience is nowadays a relevant aspect of the authenticity and the quality of many food commodities. Dehydrated apple cubes/slices represent an ingredient commonly used by food companies for bakery products. However, this apple-based matrix is not so known and studied from an analytical point of view. In the present work, seven compounds were identified as key molecules to distinguish between Italian and non-Italian samples, through an untargeted ultrahigh-pressure liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) approach. This methodology was merged with multivariate statistical analysis, and the principal features were studied and identified considering several identification steps. Samples from 2020 and 2021 harvesting campaigns, with partial and total dehydration rates, with or without peel, and from different apple varieties were considered for the study, for a total of 91 samples. Afterward, the same analysis protocol was applied to an external set (n = 12 samples), included in the statistical models, searching for the key compounds identified in the training set. Interesting and significant results underlined the potentiality of the UHPLC-HRMS technology as a confirmatory strategy for the geographical origin assessment of dehydrated apple commodities. 相似文献
712.
Junyan Zhang Mengqi Li Runxin Xu Suman Kapur Antonio Bombard Yongxin Song 《Electrophoresis》2023,44(1-2):323-336
Infections caused by antimicrobial resistance are a serious problem in the world. Currently, commercial devices for antimicrobial susceptibility testing and resistant bacteria identification are time-consuming. There is an urgent need to develop fast and accurate methods, especially in the process of sample pretreatment. Electrokinetic (EK) is a family of electric-field-based kinetic phenomena of fluid or embedded objects, and EK applications have been found in various fields. In this paper, EK bacteria manipulation, including enrichment and separation, is reviewed. Focus is given to the rapid electric-based minimum inhibitory concentration measurement. The future directions and major challenges in this field are also outlined. 相似文献
713.
Mixed-Valence CuI/CuIII Metal–Organic Frameworks with Non-innocent Ligand for Multielectron Transfer
Shang-Yuan Fu Cheng-Han Chang Dr. Alexander S. Ivanov Dr. Ilja Popovs Dr. Jeng-Lung Chen Dr. Yen-Fa Liao Dr. Hsin-Kuan Liu Dr. Suman Chirra Prof. Dr. Yun-Wei Chiang Jui-Chin Lee Wei-Ling Liu Prof. Dr. Watchareeya Kaveevivitchai Prof. Dr. Teng-Hao Chen 《Angewandte Chemie (International ed. in English)》2023,62(50):e202312494
We report two novel three-dimensional copper-benzoquinoid metal–organic frameworks (MOFs), [Cu4L3]n and [Cu4L3 ⋅ Cu(iq)3]n (LH4=1,4-dicyano-2,3,5,6-tetrahydroxybenzene, iq=isoquinoline). Spectroscopic techniques and computational studies reveal the unprecedented mixed valency in MOFs, formal Cu(I)/Cu(III). This is the first time that formally Cu(III) species are witnessed in metal–organic extended solids. The coordination between the mixed-valence metal and redox-non-innocent ligand L, which promotes through-bond charge transfer between Cu metal sites, allows better metal-ligand orbital overlap of the d-π conjugation, leading to strong long-range delocalization and semiconducting behavior. Our findings highlight the significance of the unique mixed valency between formal Cu(I) and highly-covalent Cu(III), non-innocent ligand, and pore environments of these bench stable Cu(III)-containing frameworks on multielectron transfer and electrochemical properties. 相似文献
714.
Varun Kumar Sing Souvik Sur Mohd. Musharraf Ratan Kumar Dey Sanjay Kumar Swain Suman Shekhar 《Macromolecular Symposia》2024,413(1):2300045
In the present study, the degradation process of piperazine (PP) immobilized silica gel (SiPP) is investigated under dynamic conditions. The degradation of SiPP is studied with thermogravimetric analyzer (TGA). The kinetics of degradation process is analyzed by Kissinger method, Flynn–Wall–Ozawa's (FWO) method, and Deconvolution method. It is found that degradation of SiPP can be described by parallel independent two-portion process model, which includes two processing state of the system (marked by processes 1 and 2), where process 1 and 2 can be attributed to decomposition processes of organic moiety attached on silica surface. The apparent activation energy (Ea) is calculated by Flynn–Wall–Ozawa's (FWO) method and deconvolution method. 相似文献
715.
Correction to: Non‑precious transition metal‑based counter electrodes for dye‑sensitized solar cells
Journal of Solid State Electrochemistry - 相似文献
716.
Bio-derived ethanol is a promising green and sustainable hydrogen-donor solvent. Herein, we have developed Ir-catalyzed transfer hydrogenation of ketones and aldehydes using ethanol as a hydrogen source with amides as simple ligands. Furthermore, the alkylation of ketones and tandem alkylation/transfer hydrogenation of acetophenones is reported with ethanol. 相似文献
717.
Journal of Solid State Electrochemistry - A non-platinum metal catalyst, TiNx-C, was synthesized through the high-pressure pyrolysis method, which was characterized using a transmission electron... 相似文献