The physico-chemical research on rice starch : 4. On the X-ray diffraction of rice starch

1956 ◽  
Vol 25 (2) ◽  
pp. 81-86
Author(s):  
Saisuke UEDA ◽  
Isamu OTA
2013 ◽  
Vol 832 ◽  
pp. 589-595 ◽  
Author(s):  
N.A. Edama ◽  
A. Sulaiman ◽  
K.H. Ku Hamid ◽  
M.N. Muhd Rodhi ◽  
Mohibah Musa ◽  
...  

This study analyzed the effects of sulphuric acid (H2SO4) treatment on pysico-chemical properties and morphological changes of clay obtained from Sg. Sayong, Perak. The clay was ground and sieved to <150μm and treated with different concentrations of H2SO4. The treatment was completed by refluxing the clay with different concentration of H2SO4 (1M, 5M and 10M ) at 100 °C for 4 hours and followed by calcination at 500 °C for 1 hour. The physic-chemical properties and morphological changes of the untreated and treated clay were compared using Surface Area Analyser, X-Ray Diffraction (XRD), Field Emission Scanning Electron Micrograph (FESEM), X-Ray Diffraction (XRD) and Fourier Transformed Infrared Spectroscopy (FTIR). The results showed that acid treatment of 5M increased the surface area from 25 m2/g to 75 m2/g and the pore volume increased from 0.1518 cc/g to 0.3546 cc/g. The nanopore size of the clay decreased from 24.8 nm to 19.4 nm after treated with acid. This can be explained due to the elimination of the exchangeable cations and generation of microporosity. The results of XRF showed SiO2 increased from 58.34% to 74.52% and Al2O3 reduced from 34.6% to 18.31%. The mineral oxides such as Fe2O3, MgO, CaO, K2O and TiO2 also reduced. This concluded that H2SO4 treatment has led to significant removal of octahedral Al3+, Fe3+ cations and other impurities. In conclusion, this study showed the physico-chemical properties and morphology of Sayong clay were improved once treated with H2SO4 and therefore suggests better supporting material for enzyme immobilization.


2012 ◽  
Vol 727-728 ◽  
pp. 1387-1392 ◽  
Author(s):  
Luan M. Medeiros ◽  
Fernando S. Silva ◽  
Juliana Marchi ◽  
Walter Kenji Yoshito ◽  
Dolores Ribeiro Ricci Lazar ◽  
...  

Zirconium dioxide (zirconia) ceramics are known by its high strength and toughness and titanium dioxide (titania) ceramics has outstanding surface properties. The ceramic composite formed between the two oxides are expected to have advantages of both ceramics, especially when its surface area is increased by pores. In this work, ceramic composites of ZrO2-Y2O3-TiO2were synthesized by coprecipitation and rice starch was added as pore former in 10, 20 and 30 wt%. Powders were cold pressed as cylindrical pellets and sintered at 1500 °C for 01 hour and ceramics were characterized by techniques as Archimedes method for density measurements, X-ray diffraction and scanning electron microscopy. Results showed that pores are inhomogeneously distributed through ceramic bodies.


2018 ◽  
Vol 3 (8) ◽  
pp. 56
Author(s):  
Amie Thant ◽  
Chaw Su Su Hmwe

In this study, the performance of different acid treated Myanmar Natural Clay (Mabisian) was conducted the pyrolysis of mixed plastic wastes, 40% high density polyethylene, 30% polypropylene, 25% low density polyethylene and 5% polystyrene. Mabisian clay was refluxed with different concentration of nitric acid (2M, 4M, 6M, 8M, 10M, 12M and 14M)  at 100ºC for 3hrs followed by calcination at 500ºC for 1hr. The physico-chemical characteristics of resulted leached clay were studied by X-Ray Fluoresence spectroscopy (XRF), X-Ray Diffraction (XRD) and Fourier Transformed Infrared Spectroscopy (FTIR). The pyrolytic oil was characterized by Gas Chromatography – mass spectopy (GC-MS). XRF and FTIR studies indicated that acid treatment under reflux condition lead to the removal of octahedral Al3+ cations along with other impurities.  The chemical treatment increased the Si/Al ratio.  The maximum liquid yield (75%) was obtained at 12 M nitric acid, 3hr reaction time and 100 º C reaction temperatures. In addition, the percent peak area of gasoline range hydrocarbon was obtained 55.6% at optimum condition. Thus, the treated clay can be used as promising as catalyst support.


Author(s):  
Nitu Bhatnagar ◽  
Avani Pareek

The present study is aimed to observe the difference in the Physico-Chemical characteristics of the marketed and formulated bhasma samples through X-Ray Diffraction analysis (XRD), Dynamic Light Scattering (DLS), Zeta potential, Thermo-Gravimetric analysis (TGA), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray analysis (EDAX), apart from organoleptic methods. Inductively Coupled Plasma Mass Spectroscopy (ICPMS) analysis was also done to observe the presence of trace and heavy metals so that the safety of all these samples could be ensured. XRD shows variation in oxide nature of zinc as well crystallite size in all bhasma samples. DLS and SEM results show difference in particle size of marketed bhasma samples as compared to formulated Yashada bhasma. EDAX and ICPMS also confirm the alteration in elemental composition of all these bhasma samples. Thus, it can be concluded that these ayurvedic medicines should be prepared strictly using the formulation methods as mentioned in the Ayurvedic texts. This will help the prepared products to adopt the inherent quality of the ancient system of medicine, which shall be useful and devoid of any side effects for human consumption.


Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 476 ◽  
Author(s):  
Xuan-Dien Luong ◽  
Xuan-Truong Nguyen

A [O,N] bidentate π-expanded ligand system, (E)-1-(n-octylimino)methylpyren-2-ol (2), was newly synthesized via a six-step synthesis from pyrene. The ligand 2 reacts with [PtCl2(PhCN)2] in chlorobenzene and the presence of a base at reflux for 2 h under the formation of (2(Pt)) complex with a yield of 70%. The molecular structure of (2(Pt)), studied by common spectroscopic methods and X-ray diffraction, shows a square planar geometry with a trans-configuration of the ligands. The molecular structure, absorption spectra, electrochemical properties, and phosphorescence characteristics of the (2(Pt)) complex are discussed, emphasizing the comparison with those of the previously reported Pt complex (1(Pt)) containing the isomeric ligands of 2, (E)-2-(n-octylimino)methylpyren-1-ol. The DFT calculations of the two Pt complexes are carried out and exhibit a clear explanation of the relationship between their physico-chemical characteristics.


2019 ◽  
Vol 9 (13) ◽  
pp. 2598 ◽  
Author(s):  
M. J. Hernández-Rodríguez ◽  
R. Santana Rodríguez ◽  
R. Darias ◽  
O. González Díaz ◽  
J. M. Pérez Luzardo ◽  
...  

In this study, mortar specimens were prepared with a cement:sand:water ratio of 1:3:0.5, in accordance with standard EN196-1. Portland CEM I 52.5 R grey (G) and white (W) cements were used, together with normalised sand and distilled water. Different amounts of TiO2 photocatalyst were incorporated in the preparation of the mortar samples. The effect of the addition of TiO2 was studied on mechanical properties of the mortar and cement including compressive and flexural strength, consistency (the flow table test), setting time and carbonation. Characterization techniques, including thermogravimetry, mercury porosimetry and X-ray diffraction spectroscopy (XRD), were applied to study the physico-chemical properties of the mortars. It was shown that adding the photocatalyst to the mortar had no negative effect on its properties and could be used to accelerate the setting process. Specimen photoactivity with the incorporated photocatalyst was tested for NOx oxidation in different conditions of humidity (0% RH and 65% RH) and illumination (Vis or Vis/UV), with the results showing an important activity even under Vis radiation.


2013 ◽  
Vol 2013 ◽  
pp. 1-8
Author(s):  
Y. C. Wong ◽  
Y. H. Taufiq-Yap

Four VPO catalysts were synthesized through intercalation and exfoliation in various alcohols and subsequent reduction of the exfoliated VOPO4sheets with various alcohols to produce VOHPO4⋅0.5H2O. The resulting VOHPO4⋅0.5H2O that undergoes the intercalation-exfoliation-reduction (IER) process will be further activated into VPO catalysts, and addition of 1 mole % Bi(NO3)3⋅5H2O in the first stage of this experiment has also being investigated. The synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and temperature-programmed reduction (TPR) in H2. Catalytic evaluation of the IER-treated and Bi-doped VPO catalysts was also studied on microreactor. The VPO catalyst produced through IER using 2-butanol and ethanol with addition of Bi, IERC(2Bu-Et)RBi1, gave the highest MA selectivity due to reactive O2−species released from the additional crystalline V5+phase formed by doping 1% bismuth as promoter (O2−-V5+pair) at relative lower temperature. Nevertheless, the VPO catalyst produced through IER using isobutanol, IERC(isoBu), gave the highest activity due to high amount of reactive O−species released from V4+phase (O−-V4+pair) whereby the IERC(isoBu) catalyst synthesized consists of high percentage of V4+(93 %).


1995 ◽  
Vol 28 (2) ◽  
pp. 131-169 ◽  
Author(s):  
Jean-Pierre Benoit ◽  
Jean Doucet

The understanding of flexibility and deformability in proteins is one of the current major challenges of structural molecular biology. The knowledge of the average atomic positions of three-dimensional folding of proteins, which is obtained either by X-ray diffraction or n.m.r. spectroscopy, is generally not sufficient to explain their functional mechanisms. Very often it is necessary to consider the existence of other concerted atomic motions as, for example, in the well-known case of the CO molecule fixation at the active site of myoglobin which requires the concerted displacement of a large number of atoms in order to open a channel down to this site. This opening, which depends on the physico-chemical conditions, plays the role of a regulator in the biochemical reactions (Janin & Wodak, 1983; Tainer et al. 1984; Westhof et al. 1984; Ormos et al. 1988).


2002 ◽  
Vol 712 ◽  
Author(s):  
Antonia Moropoulou ◽  
Ekaterini T. Delegou ◽  
Nicolas P. Avdelidis ◽  
Maria Koui

ABSTRACTIn this work, pilot cleaning interventions applied by a wet micro-blasting method on architectural surfaces of three historic buildings in marble and porous stone were evaluated in situ and in the laboratory. The investigation was performed on characteristic stone surfaces (marbles and porous stone) of the following historic buildings: Athens Academy and National Library of Greece in Athens center polluted urban environment and Bank of Greece in Piraeus marine environment. The materials of the facades were characterized, and the mechanism of decay was diagnosed. In addition, the cleaning method's efficiency was evaluated based on the acceptability of the alteration of the cleaned architectural surfaces. Criteria were both aesthetic and physico-chemical. In particular, the architectural surfaces were examined in situ by the means of fiber optic microscopy, infrared thermography and colorimetry. In the laboratory, methods of investigation were optical microscopy, X-ray diffraction, scanning electron microscopy with energy dispersion by X-ray analysis, mercury intrusion porosimetry, Fourier transform infrared spectroscopy, conductivity and pH measurements. The majority of measurements and analyses were applied before and after the pilot cleaning interventions. Finally, the results of this study contribute to the development of an integrated methodology for the assessment of cleaning interventions applied on architectural surfaces.


2014 ◽  
Vol 775-776 ◽  
pp. 471-475
Author(s):  
Renata Barbosa ◽  
Tatianny Soares Alves ◽  
Celso Hartmann Júnior ◽  
Gabriel Neiva Cadah

The physico-chemical characteristics of attapulgite clay confer appropriate properties to their different industrial uses, such as: Drilling fluid, bleaching of vegetable oils, mineral and animal grease and oil absorbents, pet waste absorbents (pet litter), purification of drinking water etc. The aim of this study was the chemical modification of attapulgite originally from state of Piauí, for applications in polyester-based composites. The unmodified and modified clay were characterized by X-ray diffraction (XRD). In order to evaluate the interaction of clays with organic solvents, the test of Foster swelling with gasoline, diesel and toluene was conducted. The polyester resin-based composite and clay unmodified and modified in different percentages were molded by hand lay up technique and they were characterized by water sorption.


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