SPECTROSCOPIC STUDIES OF SOME PHOSPHATE GLASSES WITH MOLYBDENUM IONS

2005 ◽  
Vol 19 (10) ◽  
pp. 1815-1820 ◽  
Author(s):  
D. A. MAGDAS ◽  
O. COZAR ◽  
I. ARDELEAN ◽  
L. DAVID
Keyword(s):  
Spectroscopic Studies ◽  
Phosphate Glasses ◽  
Structural Units ◽  
Bending Vibrations ◽  
Phosphate Chain ◽  
Ir And Raman Spectroscopies ◽  
Ring Structures ◽  
Ir And Raman ◽  
Structural Aspects

The structure of x MoO 3·(100-x)[2 P 2 O 5· PbO ] glass system with 0≤x≤50 mol % is investigated by IR and Raman spectroscopies. The characteristic bands of the glass matrix [2 P 2 O 5· PbO ] and MoO 3 oxide due to the stretching and bending vibrations are identified. This allows us to identify the specific structural units which occur in these glasses and to deduce the role of the MoO 3 oxide on the structural aspects of 2 P 2 O 5· PbO network. At high MoO 3 content a depolymerization of the phosphate structure appears and the short phosphate chain units or ring structures are formed too.

FT-IR AND RAMAN SPECTROSCOPIC STUDIES OF xAg2O · (100 - x)[B2O3 · As2O3] GLASS SYSTEM

2010 ◽  
Vol 24 (01) ◽  
pp. 51-58 ◽  
Author(s):  
S. C. BAIDOC ◽  
I. ARDELEAN
Keyword(s):  
Ir Spectroscopy ◽  
Structural Changes ◽  
Spectroscopic Studies ◽  
Glass System ◽  
Structural Units ◽  
Raman Spectroscopic ◽  
Ir And Raman Spectroscopies ◽  
Ft Ir ◽  
Ir And Raman ◽  
Ft Ir Spectroscopy

Structural analysis of x Ag 2 O · (100-x)[ B 2 O 3 · As 2 O 3] glass system, with 0 ≤ x ≤ 10 mol%, was performed by means of FT-IR and Raman spectroscopies. The purpose of this work is to investigate the structural changes that appear in the B 2 O 3 · As 2 O 3 glass matrix with the addition and increase of silver ion content. Boroxol rings, pyro-, ortho-, di-, tri-, tetra- and penta-borate groups, structural units characteristic to As 2 O 3 were found in the structure of the studied glasses. FT-IR spectroscopy measurements show that BO 3 units are the main structural units of the glass system. The presence of structural units characteristic to Ag 2 O were not directly evidenced by FT-IR spectroscopy. The Raman analysis leads to similar conclusions as the FT-IR measurements.

scholarly journals Sonochemical-assisted magnesium borate synthesis from different boron sources

2017 ◽  
Vol 19 (1) ◽  
pp. 81-88 ◽  
Author(s):  
Meral Yildirim ◽  
Azmi Seyhun Kipcak ◽  
Emek Moroydor Derun
Keyword(s):  
High Efficiency ◽  
Synthesis Method ◽  
Spectroscopic Studies ◽  
X Ray Diffraction ◽  
Magnesium Borate ◽  
Ir And Raman Spectroscopies ◽  
Ft Ir ◽  
Surface Morphologies ◽  
Ir And Raman ◽  
Good Agreement

Abstract In this study, sonochemical-assisted magnesium borate synthesis is studied from different boron sources. Various reaction parameters are successfully applied by a simple and green method. X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and Raman spectroscopies are used to characterize the synthesized magnesium borates on the other hand surface morphologies are investigated by using scanning electron microscope (SEM). The XRD analyses showed that the products were admontite [MgO(B2O3)3 · 7(H2O)] with JCPDS (Joint Committee on Powder Diffraction Standards) no. of 01-076-0540 and mcallisterite [Mg2(B6O7(OH)6)2 · 9(H2O)] with JCPDS no. of 01-070-1902. The results that found in the spectroscopic studies were in a good agreement with characteristic magnesium borate bands in both regions of infra-red and visible. According to SEM results, obtained borates were in micro and sub-micro scales. By the use of ultrasonication, reaction yields were found between 84.2 and 97.9%. As a result, it is concluded that the sonochemical approach is a practicable synthesis method to get high efficiency and high crystallinity in the synthesis magnesium borate compounds.

INFRARED SPECTRA OF CALCIUM PHOSPHATE GLASSES

2010 ◽  
Vol 24 (03) ◽  
pp. 351-358 ◽  
Author(s):  
D. TOLOMAN ◽  
D. A. MAGDAS ◽  
I. BRATU ◽  
L. M. GIURGIU ◽  
I. ARDELEAN
Keyword(s):  
Calcium Phosphate ◽  
Ir Spectroscopy ◽  
Experimental Spectrum ◽  
Phosphate Glasses ◽  
Structural Units ◽  
Bending Vibrations ◽  
Ft Ir ◽  
Infrared Absorption Spectra ◽  
Gaussian Type Function ◽  
Ft Ir Spectroscopy

Infrared absorption spectra of calcium phosphate glasses, x CaO ·(100-x) P 2 O 5 have been investigated by FT-IR spectroscopy. By increasing CaO content, the characteristic bands due to the stretching and bending vibrations were identified and analyzed. The deconvolution of each experimental spectrum was made using a Gaussian-type function. Based on this, the specific structural units of these glasses were identified.

FT-IR AND RAMAN SPECTROSCOPIC STUDIES OF GADOLINIUM DOPED B2O3 · TeO2 GLASS MATRIX

2007 ◽  
Vol 21 (26) ◽  
pp. 1767-1774 ◽  
Author(s):  
L. GRIGUTA ◽  
I. ARDELEAN
Keyword(s):  
Glass Matrix ◽  
Spectroscopic Studies ◽  
Absorption Characteristic ◽  
Ir Absorption ◽  
Spectroscopic Techniques ◽  
Structural Units ◽  
Raman Spectroscopic ◽  
Ft Ir ◽  
Ir And Raman ◽  
No Absorption

Glasses from x Gd 2 O 3 · (100-x)[ B 2 O 3 · TeO 2] system with 0 ≤ x ≤ 10 mol% have been prepared and studied by means of FT-IR absorption and Raman scattering. Being complementary spectroscopic techniques, both types of measurements FT-IR and Raman revealed that the network structure of the studied glasses is based on BO 3 and BO 4 units placed in different structure groups and also TeO 4, TeO 3 structural units. No absorption characteristic for Gd 2 O 3 was evidenced but some changes in the structure of B 2 O 3 · TeO 2 glass matrix are due to its presence.

STRUCTURAL INVESTIGATIONS OF THE MnO–Bi3O3–CdO GLASS SYSTEM BY IR AND RAMAN SPECTROSCOPIES

2004 ◽  
Vol 18 (07n08) ◽  
pp. 275-279
Author(s):  
I. ARDELEAN ◽  
IOANA TODOR ◽  
P. PǍŞCUŢǍ
Keyword(s):  
Ir Spectroscopy ◽  
Local Structure ◽  
Glass Network ◽  
Glass System ◽  
Spectral Measurements ◽  
Structural Units ◽  
Structural Investigations ◽  
Ir And Raman Spectroscopies ◽  
Raman Spectral ◽  
Ir And Raman

Homogeneous glasses are formed in the MnO – Bi 3 O 3– CdO system, up to 50 mol% MnO . For these glasses, IR and Raman spectral measurements are carried out in order to elucidate the local structure. We identify by IR spectroscopy both the structural units BiO 3 and BiO 6. The Raman investigation confirms the prevalence of BiO 6 groups in the glass network for all concentrations. The number of these structural groups progressively increases with MnO content.

STRUCTURAL INVESTIGATION OF Fe2O3-B2O3-KF GLASSES BY IR AND RAMAN SPECTROSCOPIES

2004 ◽  
Vol 18 (10n11) ◽  
pp. 1651-1658 ◽  
Author(s):  
P. PĂŞCUŢĂ ◽  
D. MANIU ◽  
I. ARDELEAN
Keyword(s):  
Local Structure ◽  
Structural Investigation ◽  
Glass System ◽  
Iron Ions ◽  
Structural Units ◽  
Structure Of Glasses ◽  
Ir And Raman Spectroscopies ◽  
Ir And Raman

Glasses of the x Fe 2 O 3·(100-x)[3 B 2 O 3· KF ] system, with 0≤x≤35 mol %, were prepared and investigated by infrared (IR) and Raman spectroscopies in attempt to determine the local structure of glasses. The results shown that BO 3 and BO 4 are the main structural units of the glass system and the iron ions are located in the network as FeO 4 and FeO 6.

The Non-Causal Character of Renormalization Group Explanations

2018 ◽  
Author(s):  
Margaret Morrison
Keyword(s):  
Probability Theory ◽  
Renormalization Group ◽  
Dynamical Systems ◽  
Recent Literature ◽  
Mathematical Explanation ◽  
Causal Status ◽  
Physical Information ◽  
The Relationship ◽  
Structural Aspects

After reviewing some of the recent literature on non-causal and mathematical explanation, this chapter develops an argument as to why renormalization group (RG) methods should be seen as providing non-causal, yet physical, information about certain kinds of systems/phenomena. The argument centres on the structural character of RG explanations and the relationship between RG and probability theory. These features are crucial for the claim that the non-causal status of RG explanations involves something different from simply ignoring or “averaging over” microphysical details—the kind of explanations common to statistical mechanics. The chapter concludes with a discussion of the role of RG in treating dynamical systems and how that role exemplifies the structural aspects of RG explanations which in turn exemplifies the non-causal features.

Structural, magnetic and Mössbauer spectroscopic studies of the [Fe(3-bpp)2](CF3COO)2 complex: role of crystal packing leading to an incomplete Fe(ii) high spin ⇋ low spin transition

CrystEngComm ◽  
2021 ◽  
Vol 23 (15) ◽  
pp. 2854-2861
Author(s):  
Kristian Handoyo Sugiyarto ◽  
Djulia Onggo ◽  
Hiroki Akutsu ◽  
Varimalla Raghavendra Reddy ◽  
Hari Sutrisno ◽  
...  
Keyword(s):  
High Spin ◽  
Crystal Packing ◽  
Spin Transition ◽  
Spectroscopic Studies ◽  
Mononuclear Complex

Mononuclear complex [Fe(3-bpp)2](CF3COO)2 exhibits a thermal (HS + HS) ⇋ (HS + LS) transition at ∼226 K which is not associated with any crystallographic transition.

Autonom autobiografisch: Zu Thomas Manns Die Entstehung des Doktor Faustus

2020 ◽  
Vol 55 (1) ◽  
pp. 83-99
Author(s):  
Lukas Hermann
Keyword(s):  
Thomas Mann ◽  
Autobiographical Writing ◽  
Documentary Source ◽  
Textual Evidence ◽  
Structural Frame ◽  
The Status ◽  
Structural Aspects

AbstractIn its peritext, Thomas Mann’s Entstehung des Doktor Faustus is described as a “Roman eines Romans”. The essay reasons that this description of its genre as well as structural aspects of its composition mark it as an autobiographical text. Instead of following most studies on the Doktor Faustus, which regard the Entstehung simply as a documentary source for exposing autobiographical intricacies of Mann’s novel, textual evidence for the Entstehung’s autonomy is given. The analysis focuses first on the structural frame of the Entstehung in order to show Mann’s central techniques of autobiographical self-stylization. In this context auto-fictional elements can also be identified. Exemplary passages from two longer sections are taken into account based on these findings. While the Doktor Faustus is a recurrent topic in these passages, it is not, by any means, the only one. Combined with varying autobiographical writing techniques, the Entstehung is thus displaying continuous independence from the Faustus. Based on these insights, future Mann studies on both works may reevaluate the role of the Entstehung for the reception of the Faustus and the status of autobiographical literature in the works of Thomas Mann.

scholarly journals Experimental and Theoretical Studies of Sonically Prepared Cu–Y, Cu–USY and Cu–ZSM-5 Catalysts for SCR deNOx

Catalysts ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 824
Author(s):  
Przemysław J. Jodłowski ◽  
Izabela Czekaj ◽  
Patrycja Stachurska ◽  
Łukasz Kuterasiński ◽  
Lucjan Chmielarz ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Ultrasonic Irradiation ◽  
Active Phase ◽  
Spectroscopic Studies ◽  
In Situ Drifts ◽  
Ft Ir ◽  
Diffuse Reflectance Infrared ◽  
Experimental And Theoretical Studies

The objective of our study was to prepare Y-, USY- and ZSM-5-based catalysts by hydrothermal synthesis, followed by copper active-phase deposition by either conventional ion-exchange or ultrasonic irradiation. The resulting materials were characterized by XRD, BET, SEM, TEM, Raman, UV-Vis, monitoring ammonia and nitrogen oxide sorption by FT-IR and Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). XRD data confirmed the purity and structure of the Y/USY or ZSM-5 zeolites. The nitrogen and ammonia sorption results indicated that the materials were highly porous and acidic. The metallic active phase was found in the form of cations in ion-exchanged zeolites and in the form of nanoparticle metal oxides in sonochemically prepared catalysts. The latter showed full activity and high stability in the SCR deNOx reaction. The faujasite-based catalysts were fully active at 200–400 °C, whereas the ZSM-5-based catalysts reached 100% activity at 400–500 °C. Our in situ DRIFTS experiments revealed that Cu–O(NO) and Cu–NH3 were intermediates, also indicating the role of Brønsted sites in the formation of NH4NO3. Furthermore, the results from our experimental in situ spectroscopic studies were compared with DFT models. Overall, our findings suggest two possible mechanisms for the deNOx reaction, depending on the method of catalyst preparation (i.e., conventional ion-exchange vs. ultrasonic irradiation).

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