Other spectroscopic methods for graphene characterization: X-ray and electron spectroscopies

A two-sided wooden icon from a monastery in Transylvania was submitted for multidisciplinary investigations involving X-Ray Fluorescence, Radiographic Photographyand Fourier Transform Infrared Spectroscopy. The most important part of the icon is St. Nicholas wooden icon, painted over forty years ago. The spectroscopic methods used revealed the painting materials composition, the status of the wooden stage, and the presence of resins as varnish (Fourier Transform Infrared Spectroscopy). On one side, the St Nicholasicon was painted over an old icon, St. Arch. Michael, which was evidenced by X-Ray Photography. The obtained data can serve for the preservation and the restoration of these wooden icons.

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The protonation of the ethylenediphosphinetetraacetate anion and the crystal structure of the bis (hydrogen bromide) of ethylenediphosphinetetraacetic acid

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19813063 ◽

1981 ◽

Vol 46 (12) ◽

pp. 3063-3073 ◽

Cited By ~ 5

Author(s):

Jana Podlahová ◽

Bohumil Kratochvíl ◽

Vratislav Langer ◽

Josef Šilha ◽

Jaroslav Podlaha

Keyword(s):

Crystal Structure ◽

Hydrogen Bonds ◽

Structure Determination ◽

Free Acid ◽

Hydrogen Bromide ◽

Carboxyl Groups ◽

Spectroscopic Methods ◽

X Ray ◽

Partial Formation

The equilibria and mechanism of addition of protons to the ethylenediphosphinetetraacetate anion (L4-) were studied in solution by the UV, IR, 1H and 31P NMR spectroscopic methods. A total of six protons can be bonded to the anion. They are added stepwise, first with partial formation of zwitterions containing P-H bonds, which then dissociate with formation of the free acid, H4L, where all four protons are bonded in carboxyl groups. The formation of zwitterions is strongly dependent on the concentration. In the final stage, the acid bonds two additional protons to form the bis-phosphonium cation, H6L2+. A number of isostructural salts containing this cation, H4L.2 HX (X = Cl, Br, I), have been prepared. The X-ray crystal structure determination of the bromide confirmed the expected arrangement. The bromide crystals are monoclinic, a = 578.2, b = 1 425.0, c = 1 046.7 pm, β = 103.07° with a space group of P21/c, Z = 2. The final R factor was 0.059 based on 1 109 observed reflections. The structure consists of H6L2+ cations containing protons bonded to phosphorus atoms (P-H distance 134 pm) and of bromide anions, located in gaps which are also sufficiently large for I- anions in the isostructural iodide. The interbonding of phosphonium cations proceeds through hydrogen bonds, C-OH...O=C, in which the O...O distance is 275.3 pm.

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Bis(μ-carboxylato)dienerhodium(I) Complexes - Synthesis, Characterization and Catalytic Activity

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20081205 ◽

2008 ◽

Vol 73 (8-9) ◽

pp. 1205-1221 ◽

Cited By ~ 4

Author(s):

Jiří Zedník ◽

Jan Sedláček ◽

Jan Svoboda ◽

Jiří Vohlídal ◽

Dmitrij Bondarev ◽

...

Keyword(s):

Catalytic Activity ◽

Diffraction Analysis ◽

Spectroscopic Methods ◽

X Ray Diffraction ◽

X Ray

Dinuclear rhodium(I) η2:η2-cycloocta-1,5-diene (series a) and η2:η2-norborna-2,5-diene (series b) complexes with μ-RCOO- ligands, where R is linear C21H43 (complexes 1a, 1b), CH2CMe3 (2a, 2b), 1-adamantyl (3a, 3b) and benzyl (4a, 4b), have been prepared and characterized by spectroscopic methods. Structures of complexes 2b, 3a and 4a were determined by X-ray diffraction analysis. Complexes prepared show low to moderate catalytic activity in polymerization of phenylacetylene in THF giving high-cis-transoid polymers, but they show only oligomerization activity in dichloromethane.

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New Haloterpenes from the Marine Red Alga Laurencia papillosa: Structure Elucidation and Biological Activity

Marine Drugs ◽

10.3390/md19010035 ◽

2021 ◽

Vol 19 (1) ◽

pp. 35

Author(s):

Mohamed Shaaban ◽

Ghada S. E. Abou-El-Wafa ◽

Christopher Golz ◽

Hartmut Laatsch

Keyword(s):

Biological Activity ◽

Crude Extract ◽

Structure Elucidation ◽

Antimicrobial Activities ◽

Red Alga ◽

Spectroscopic Methods ◽

X Ray Diffraction ◽

X Ray ◽

Chemical Structures ◽

Terpene Derivatives

Analysis of the air-dried marine red alga Laurencia papillosa, collected near Ras-Bakr at the Suez gulf (Red Sea) in Egypt delivered five new halogenated terpene derivatives: aplysiolic acid (1), 7-acetyl-aplysiol (2), aplysiol-7-one (3), 11,14-dihydroaplysia-5,11,14,15-tetrol (5a), and a new maneonene derivative 6, named 5-epi-maneolactone. The chemical structures of these metabolites were characterized employing spectroscopic methods, and the relative and absolute configurations were determined by comparison of experimental and ab initio-calculated NMR, NOE, ECD, and ORD data, and by X-ray diffraction of 2 and 6. The antimicrobial activities of the crude extract and compounds 1–3, 5a and 6 were studied.

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Fusarins G–L with Inhibition of NO in RAW264.7 from Marine-Derived Fungus Fusarium solani 7227

Marine Drugs ◽

10.3390/md19060305 ◽

2021 ◽

Vol 19 (6) ◽

pp. 305

Author(s):

Guangyuan Luo ◽

Li Zheng ◽

Qilin Wu ◽

Senhua Chen ◽

Jing Li ◽

...

Keyword(s):

Fusarium Solani ◽

2D Nmr ◽

Inflammatory Activity ◽

Raw264.7 Cells ◽

Spectroscopic Methods ◽

X Ray ◽

X Ray Crystallography ◽

Structure Activity ◽

Ic50 Values ◽

New Compounds

Six new fusarin derivatives, fusarins G–L (1–6), together with five known compounds (5–11) were isolated from the marine-derived fungus Fusarium solani 7227. The structures of the new compounds were elucidated by means of comprehensive spectroscopic methods (1D and 2D NMR, HRESIMS, ECD, and ORC) and X-ray crystallography. Compounds 5–11 exhibited potent anti-inflammatory activity by inhibiting the production of NO in RAW264.7 cells activated by lipopolysaccharide, with IC50 values ranging from 3.6 to 32.2 μM. The structure–activity relationships of the fusarins are discussed herein.

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Structures, Chemical Conversions, and Cytotoxicity of Tricholopardins C and D, Two Tricholoma Triterpenoids from the Wild Mushroom Tricholoma pardinum

Natural Products and Bioprospecting ◽

10.1007/s13659-021-00297-x ◽

2021 ◽

Author(s):

Chen Shi ◽

Yue-Ling Peng ◽

Juan He ◽

Zheng-Hui Li ◽

Ji-Kai Liu ◽

...

Keyword(s):

Hela Cell ◽

Single Crystal ◽

Cell Lines ◽

Cell Apoptosis ◽

Spectroscopic Methods ◽

Wild Mushroom ◽

X Ray Diffraction ◽

X Ray ◽

Hela Cell Lines ◽

Mcf 7

AbstractTwo undescribed Tricholoma triterpenoids, namely tricholopardins C (1) and D (2), were isolated from the wild mushroom Tricholoma pardinum. Their structures with absolute configurations were elucidated by spectroscopic methods, as well as the single crystal X-ray diffraction. Compounds 1 and 2 were further obtained by chemical conversions from the known analogues. Compound 1 showed significant cytotoxicity to MCF-7 and Hela cell lines with IC50 values of 4.7 μM and 9.7 μM, respectively. Its mechanism of inducing MCF-7 cell apoptosis was studied briefly. Graphical Abstract

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SPECTROSCOPIC METHODS TO DETERMINATION OF GEOTHITE IN KAOLINITE

Periódico Tchê Química ◽

10.52571/ptq.v17.n35.2020.27_klunk_pgs_303_314.pdf ◽

2020 ◽

Vol 17 (35) ◽

pp. 303-314

Author(s):

Marcelo Kehl; ; ; ; DE SOUZA ◽

Marcos Antônio KLUNK ◽

Soyane Juceli Siqueira XAVIER ◽

Mohuli DAS ◽

Sudipta DASGUPTA

Keyword(s):

Spectroscopic Methods ◽

Industrial Minerals ◽

X Ray Diffraction ◽

Simple Shape ◽

X Ray ◽

Spectroscopic Monitoring ◽

Partial Release ◽

Primary Minerals

One of the main contaminants of kaolinite, the iron, directly impacts quality in its commercial value. The spectroscopic monitoring, measured the depth of absorption of kaolinite, is compared with the literature in order to identify possible contaminants. The occurrence of kaolinite is due to the formation of primary minerals after the partial release of cations and silicon. This clay-mineral has a simple shape, with variable crystallographic imperfections, especially in the presence of iron, which replaces aluminum in the mineral chain, causing various structural disorganizations. The extraction of industrial minerals combined with geological studies, allows the development of new sources of energy, such as clay minerals, in particular kaolinite. Depending on the origin of the kaolinites, the presence of iron oxides in its structure, Fe2O3 and FeO(OH), are common. By comparing the results of spectroscopy (X-ray fluorescence, X-ray diffraction, RAMAN) and imaging using SEM-EDS, it was possible to identify kaolinite, with a higher determination coefficient, when the proportion of kaolinite reaches 60% or more in the mix. Kaolinite can be identified and quantified with a high correlation in the mixture from the sample absorption. Thus, the method has great potential to assist in quantifying and, consequently, in discriminating the quality of kaolinite.

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Formation of ZnO Doped with Mn Thin Film by Electrodeposition and Magnetic Behaviour.

MRS Proceedings ◽

10.1557/proc-879-z7.17 ◽

2005 ◽

Vol 879 ◽

Author(s):

M. Abid ◽

C. Terrier ◽

J-P Ansermet ◽

K. Hjort

Keyword(s):

Thin Film ◽

Thin Films ◽

Room Temperature ◽

Magnetic Behaviour ◽

Spectroscopic Methods ◽

X Ray Diffraction ◽

X Ray ◽

Doped Zno ◽

Mn Doped ◽

Weak Ferromagnetic

AbstractFollowing the theory, ferromagnetism is predicted in Mn- doped ZnO, Indeed, ferromagnetism above room temperature was recently reported in thin films as well as in bulk samples made of this material. Here, we have prepared Mn doped ZnO by electrodeposition. The samples have been characterized by X-ray diffraction and spectroscopic methods to ensure that the dopants are substitutional. Some samples exhibit weak ferromagnetic properties at room temperature, however to be useful for spintronics this material need additional carriers provided by others means.

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Chiral C2-Symmetric Diimines with 4,5-Diazafluorene Units

Molecules ◽

10.3390/molecules24173186 ◽

2019 ◽

Vol 24 (17) ◽

pp. 3186 ◽

Cited By ~ 1

Author(s):

Vasilyev ◽

Bizyaev ◽

Komarov ◽

Gatilov ◽

Tkachev

Keyword(s):

Calculated Data ◽

Transition Metal Ions ◽

Synthetic Approach ◽

Spectroscopic Methods ◽

Aromatic Diamines ◽

X Ray ◽

X Ray Crystallography ◽

Chemical Structures ◽

Polydentate Ligands ◽

New Compounds

A synthetic approach to a new group of stable chiral C2-symmetric diimines with the 4,5-diazafluorene core has been developed based on condensation of dipinodiazafluorene with aromatic diamines. The chemical structures of new compounds were proven by spectroscopic methods and X-ray crystallography. All the compounds form solvates with organic solvents (chloroform, benzene, 1,4-dioxane) and water. Specific spectral data of the new compounds are explained using calculated data (DFT). Diimines of the pinodiazafluorene series give colored reactions with transition metal ions and can be regarded as prospective polydentate ligands with interesting luminescent and chiroptical properties.

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Bimetallic DppfM(II) (M = Pt and Pd) dithiocarbamate complexes: Synthesis, characterization, and anticancer activity

Journal of Chemical Research ◽

10.1177/1747519819871029 ◽

2019 ◽

Vol 43 (9-10) ◽

pp. 437-442 ◽

Cited By ~ 3

Author(s):

Shou De Xu ◽

Xiang Hua Wu

Keyword(s):

Antitumor Activity ◽

Platinum Complex ◽

Spectroscopic Methods ◽

X Ray Diffraction ◽

Antitumor Activities ◽

High Potency ◽

Promising Candidate ◽

X Ray ◽

Mtt Assays

A series of bimetallic dppfM(II) (dppf = 1,1’-bis (diphenyphosphino) ferrocene; M = Pt and Pd) dithiocarbamate complexes is synthesized and characterized by spectroscopic methods and single-crystal X-ray diffraction. Their antitumor activities in vitro are investigated by MTT assays against four cancer cell lines. The anticancer studies indicate most of the complexes display good to excellent antitumor activity. Remarkably, the platinum complex with a pyrrolidinyl substituent (3b) was identified as the most promising candidate due to its high potency and broad spectrum of activity.

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