X-ray photoelectron spectroscopic studies of the thermal stability of chlorophyll a monohydrate

1976 ◽  
Vol 98 (8) ◽  
pp. 2369-2370 ◽  
Author(s):  
Nicholas Winograd ◽  
Allan Shepard ◽  
Dale H. Karweik ◽  
Vaughn J. Koester ◽  
Francis K. Fong
Keyword(s):  
Thermal Stability ◽  
Chlorophyll A ◽  
Spectroscopic Studies ◽  
X Ray ◽  
Thermal Stability Of

scholarly journals Synthesis and photocatalytic properties of Sn–TiO2 nanomaterials

2020 ◽  
Vol 10 (01n02) ◽  
pp. 2060018
Author(s):  
E. M. Bayan ◽  
T. G. Lupeiko ◽  
L. E. Pustovaya ◽  
M. G. Volkova
Keyword(s):  
Phase Transition ◽  
Thermal Stability ◽  
Sol Gel ◽  
Rutile Phase ◽  
Photocatalytic Properties ◽  
Light Activation ◽  
X Ray ◽  
Tio2 Nanomaterials ◽  
Visible Light Activation ◽  
Thermal Stability Of

Sn-doped TiO2 nanomaterials were synthesized by sol–gel method. It was shown the phase compositions and phase transitions change with the introduction of different tin amounts (0.5–20[Formula: see text]mol.%). X-ray powder diffraction was used to study the effect of different tin amounts on the anatase–rutile phase transition. It was found that the introduction of ions increases the thermal stability of anatase modifications. The material’s photocatalytic activity was studied in reaction with a model pollutant (methylene blue) photodegradation under UV and visible light activation. The best photocatalytic properties were shown for material, which contains 5[Formula: see text]mol.% of Sn.

scholarly journals Improvement of the thermal stability of dendritic silver-coated copper microparticles by surface modification based on molecular self-assembly

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Tae Hyeong Kim ◽  
Hyeji Kim ◽  
Hyo Jun Jang ◽  
Nara Lee ◽  
Kwang Hyun Nam ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Photoelectron Spectroscopy ◽  
Self Assembly ◽  
Electrically Conductive ◽  
X Ray ◽  
Alkyl Chains ◽  
Conductive Film ◽  
Initial Resistance ◽  
Thermal Stability Of ◽  
Scanning Electron

AbstractIn the study reported herein, silver-coated copper (Ag/Cu) powder was modified with alkanethiols featuring alkyl chains of different lengths, namely butyl, octyl, and dodecyl, to improve its thermal stability. The modification of the Ag/Cu powders with adsorbed alkanethiols was confirmed by scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. Each powder was combined with an epoxy resin to prepare an electrically conductive film. The results confirmed that the thermal stability of the films containing alkanethiol-modified Ag/Cu powders is superior to that of the film containing untreated Ag/Cu powder. The longer the alkyl group in the alkanethiol-modified Ag/Cu powder, the higher the initial resistance of the corresponding electrically conductive film and the lower the increase in resistance induced by heat treatment.

scholarly journals Thermal stability of tungsten zone plates for focusing hard x-ray free-electron laser radiation

2012 ◽  
Vol 14 (4) ◽  
pp. 043010 ◽  
Author(s):  
D Nilsson ◽  
F Uhlén ◽  
J Reinspach ◽  
H M Hertz ◽  
A Holmberg ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Laser Radiation ◽  
Free Electron ◽  
Free Electron Laser ◽  
X Ray ◽  
Zone Plates ◽  
Thermal Stability Of

Formation and Thermal Stability of Nd0.32Y0.68Si1.7 Layers Formed by Channeled Ion Beam Synthesis

1998 ◽  
Vol 514 ◽  
Author(s):  
M. F. Wu ◽  
A. Vantomne ◽  
S. Hogg ◽  
H. Pattyn ◽  
G. Langouche ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Ion Beam ◽  
Hexagonal Structure ◽  
Orthorhombic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Good Crystalline Quality ◽  
Ion Beam Synthesis ◽  
Thermal Stability Of

ABSTRACTThe Nd-disilicide, which exists only in a tetragonal or an orthorhombic structure, cannot be grown epitaxially on a Si(111) substrate. However, by adding Y and using channeled ion beam synthesis, hexagonal Nd0.32Y0.68Si1.7 epilayers with lattice constant of aepi = 0.3915 nm and cepi = 0.4152 nm and with good crystalline quality (χmin of Nd and Y is 3.5% and 4.3 % respectively) are formed in a Si(111) substrate. This shows that the addition of Y to the Nd-Si system forces the latter into a hexagonal structure. The epilayer is stable up to 950 °C; annealing at 1000 °C results in partial transformation into other phases. The formation, the structure and the thermal stability of this ternary silicide have been studied using Rutherford backscattering/channeling, x-ray diffraction and transmission electron microscopy.

Study of Thermal Behaviour of EPDM/SBR Blends and Carbon Nanocoatings Deposited by Sputtering

2021 ◽  
Vol 875 ◽  
pp. 116-120
Author(s):  
Muhammad Alamgir ◽  
Faizan Ali Ghauri ◽  
Waheed Qamar Khan ◽  
Sajawal Rasheed ◽  
Muhammad Sarfraz Nawaz ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Weight Loss ◽  
Thermogravimetric Analysis ◽  
Thermal Behavior ◽  
Thermal Behaviour ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermal Stability Of

In this study, the effect of SBR concentration (10 Phr, 20 Phr & 30 Phr ) on the thermal behavior of EPDM/SBR blends was studied. Thermogravimetric analysis (TGA) was used to check weight loss of samples as function of temperature by heating upto 600°C. X-ray diffraction (XRD) was performed to determine quality and % crystallinity of the elastomer blends. It was seen that % crystallinity improved with an increase in the content of SBR in EPDM/SBR blends. TGA revealed that the thermal stability of EPDM/SBR blends has improved by 17% than neat EPDM. Carbon nano-coatings produced by sputtering have no beneficial influence on thermal behaviour of elastomers.

scholarly journals ALUMINA PHASE TRANSFORMATION FROM THERMAL DECOMPOSITION OF AMMONIUM ALUM SYNTHESIZED FROM KANKARA KAOLIN

2017 ◽  
Vol 36 (3) ◽  
pp. 822-828
Author(s):  
SG Bawa ◽  
AS Ahmed ◽  
PC Okonkwo
Keyword(s):  
Thermal Stability ◽  
Phase Transformation ◽  
Calcination Temperature ◽  
Starting Material ◽  
Gamma Alumina ◽  
X Ray ◽  
Alumina Phase ◽  
Ammonium Alum ◽  
Alpha Alumina ◽  
Thermal Stability Of

Thermal stability of transitional alumina phases produced from ammonium alum using Kankara kaolin as starting material was studied. Wet beneficiation method was employed to purify the starting material, after which it was calcined and dealuminated with sulphuric acid. The elemental composition, mineralogical, and physiological analyses were carried out using X-ray fluorescence (XRF), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) techniques respectively. The ammonium alum was thermally treated by varying the calcination temperature from 700 to 1200°C and varying the time of calcination from 1 to 4 h. The formation of gamma alumina began at calcination temperature of 825°C for calcination time of 3 h, which was found to be lower than reported works of 900°C. It was found to be stable at higher temperature of 1125°C, above which phase transformation to alpha alumina was observed. The observed wide range of thermal stability of the gamma alumina phase gives it good advantage to be used for high temperature applications, such as support for catalyst promoters. Alpha alumina phase formation began at 1150°C and was fully formed at 1200°C. BET specific surface area of 166 m2/g was obtained for the gamma alumina phase which was high enough for it application as support for catalyst, catalyst and adsorbent. http://dx.doi.org/10.4314/njt.v36i3.23

Syntheses, Crystal Structures and Thermal Stability of Co(II) and Zn(II) Complexes with Ethyl Carbazate

2005 ◽  
Vol 60 (5) ◽  
pp. 505-510 ◽  
Author(s):  
Tong-Lai Zhang ◽  
Jiang-Chuang Song ◽  
Jian-Guo Zhang ◽  
Gui-Xia Ma ◽  
Kai-Bei Yu
Keyword(s):  
Thermal Stability ◽  
Aqueous Solutions ◽  
Diffraction Analysis ◽  
Single Crystals ◽  
Slow Evaporation ◽  
X Ray Diffraction ◽  
Element Analysis ◽  
Thermal Stabilities ◽  
X Ray ◽  
Thermal Stability Of

Cobalt(II) and zinc(II) complexes of ethyl carbazate (ECZ), [Co(ECZ)3](NO3)2 and [Zn(ECZ)3] (NO3)2, were synthesized. Single crystals of these two compounds were grown from aqueous solutions using a slow evaporation method. Their structures have been determined by X-ray diffraction analysis. Both of them are monoclinic with space group P21/n. The complexes are further characterized by element analysis and IR measurements. Their thermal stabilities are studied by using TG-DTG, DSC techniques. When heated to 350 °C, only metal oxide was left for both complexes.

scholarly journals STUDY OF THERMAL DECOMPOSITION PRODUCTS OF NITROGEN-PHOSPHORUS-POTASSIUM FERTILIZERS BASED ON AMMONIUM NITRATE BY X-RAY DIFFRACTUON

2017 ◽  
Vol 61 (1) ◽  
pp. 72
Author(s):  
Konstantin G. Gorbovskiy ◽  
Alena S. Ryzhova ◽  
Andrey M. Norov ◽  
Denis A. Pagaleshkin ◽  
Valentina N. Kalinina ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Thermal Decomposition ◽  
Phosphoric Acid ◽  
Ammonium Nitrate ◽  
Confined Space ◽  
Decomposition Products ◽  
X Ray ◽  
Thermal Decomposition Products ◽  
Nitrogen Phosphorus ◽  
Thermal Stability Of

Complex mineral ammonium nitrate-based fertilizers are complex multicomponent salt systems possessing low thermal stability and prone to self-sustaining decomposition. This leads to the need to increase the requirements for fire and explosion safety in their manufacture, storage and transportation, caused by the fact that ammonium nitrate is a solid oxidant able to support a combustion, and its heating in confined space can lead to detonation. Components that make up such fertilizers can both reduce (phosphates and ammonium sulfate) and accelerate (chlorine compounds) decomposition of ammonium nitrate. Thus, the thermal stability of fertilizers based on ammonium nitrate largely depends on the ratio of the components that make up its composition or formed as a result of the chemical reaction. The simplest way to reduce the content of ammonium nitrate and increase the thermal stability of fertilizer without changing the content of essential nutrients is to increase the degree of phosphoric acid ammoniation. In this paper, the phase composition change of grade 22:11:11 nitrogen-phosphorus-potassium fertilizer obtained with different ammoniation degree in the process of thermal decomposition was studied by X-ray phase analysis. To obtain this fertilizer, wet-process phosphoric acid obtained sulfuric acid attack of the Khibin apatite concentrate by a hemihydrate method is used. It is shown that an increase in the ammoniation degree has a significant effect on the exothermic decomposition of ammonium nitrate and the amount of material that is released into the gas phase. The phases formed at each stage of the decomposition are determined.Forcitation:Gorbovskiy K.G., Ryzhova A.S., Norov A.M., Pagaleshkin D.A., Kalinina V.N., Mikhaylichenko A.I. Study of thermal decomposition products of nitrogen-phosphorus-potassium fertilizers based on ammonium nitrate by X-ray diffractuon. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 1. P. 72-77

scholarly journals Study of nanocomposite hafnia and zirconia based layers produced by plasma spraying

2021 ◽  
Vol 2144 (1) ◽  
pp. 012019
Author(s):  
S V Savushkina ◽  
A M Borisov ◽  
I V Suminov ◽  
E V Vysotina ◽  
A A Ashmarin
Keyword(s):  
Thermal Stability ◽  
Plasma Spraying ◽  
Subgrain Size ◽  
Xrd Analysis ◽  
Composition Analysis ◽  
X Ray ◽  
Low Pressure Plasma ◽  
Low Pressure Plasma Spraying ◽  
Thermal Stability Of ◽  
Co Doped

Abstract Nanostructured and nanocomposite layers NiCoCrAlY+ ZrO2-7%Y2O3, ZrO2-7% Y2O3+HfO2-9%Y2O3, HfO2-9%Y2O3 with thickness of ∽ 20 μm were formed by low pressure plasma spraying. The structure and composition of the layers have been studied using a scanning electron microscopy, X-ray microanalysis, and XRD analysis. Thermal stability of the coatings has been analyzed using synchronous thermal analysis at temperatures up to 1600 °C. The results of structure and composition analysis of ZrO2-7%Y2O3+HfO2-9%Y2O3 layer suggest the formation ofnanocomposite co-doped regions of the ZrO2-HfO2-Y2O3 solid solution. The layer has greater thermal stability at temperatures up to 1600 ° C and a smaller subgrain size (∽ 33 nm) than for the ZrO2-7% Y2O3 and HfO2-9%Y2O3 layers.

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