Influence of polymer solution on the morphology and local structure of NH4ZnPO4 powders synthesized by a simple precipitation method at room temperature

2022 ◽  
Vol 29 (2) ◽  
pp. 298-304
Author(s):  
Santi Phumying ◽  
Thongsuk Sichumsaeng ◽  
Pinit Kidkhunthod ◽  
Narong Chanlek ◽  
Jessada Khajonrit ◽  
...  
2003 ◽  
Vol 775 ◽  
Author(s):  
Tsuyoshi Kijima ◽  
Kenichi Iwanaga ◽  
Tomomi Hamasuna ◽  
Shinji Mohri ◽  
Mitsunori Yada ◽  
...  

AbstractEuropium-doped hexagonal-mesostructured and nanotubular yttrium oxides templated by dodecylsulfate species as well as surfactant free bulk oxides were synthesized by the homogeneous precipitation method. All the as grown nanostructured or bulk materials with amorphous or poorly crystalline frameworks showed weak luminescence bands at room temperature. On calcination at 1000°C these materials were converted into highly crystalline yttrium oxides, resulting in a total increase in intensity of all the bands by one order of magnitude. In the hexagonal-mesostructured system, the main band due to the 5D0-7F2 transition for the calcined phases showed a sharp but asymmetrical multiplet splitting indicating multiple Eu sites. Concentration quenching was found at a Eu content of 3 mol% or above for these phases. In contrast, the main emission for the calcined solids in the nanotubular system occurred as poorly resolved broad band and the intensity of the main band at higher Eu content was significantly enhanced compared with those for the other two systems.


1970 ◽  
Vol 7 (1) ◽  
pp. 259-267 ◽  
Author(s):  
S. Meenatchisundaram ◽  
R. Selvakumaran ◽  
G. Parameswari ◽  
A. Michael

Antivenom antibodies were generated in white leghorn chicken against bentonite and adjuvant coated venoms of Common Indian Poisonous Snakes (Cobra, Krait, Russell's viper and Saw Scaled viper).The antivenom from immunized chicken egg yolk were purified by polyethylene glycol (PEG) and ammonium sulphate precipitation method and further purified by DEAE cellulose ion exchange column chromatography and concentrated by polyvinyl pyrolidone powder at room temperature. The titer of antibodies was estimated using Enzyme Linked Immunosorbent Assay (ELISA).The chickens immunized with Freund's complete adjuvant showed slightly higher titre when compared to bentonite. Inhibition of lethal, edema, haemorrhagic, procoagulant and phospholipase A2 and fibrinolytic activities of snake venoms were determined. The chicken egg yolk antivenom was effective in neutralization of these toxic and enzymatic activities of venom. The median effective dose (ED50) of chicken egg yolk antibodies raised against adjuvant coated venoms showed effective neutralizing venom toxicity when compared to the antibodies raised using bentonite coated venoms.


2013 ◽  
Vol 829 ◽  
pp. 784-789 ◽  
Author(s):  
Mahmoud Zolfaghari ◽  
Mahshid Chireh

ZnO belongs to the II-VI semiconductor group with a direct band-gap of 3.2-3.37 eV in 300K and a high exciton binding energy of 60 meV. It has good transparency, high electron mobility, wide, and strong room-temperature luminescence. These properties have many applications in a wide area of emerging applications. Doping ZnO with the transition metals gives it magnetic property at room temperature hence making it multifunctional material, i.e. coexistence of magnetic, semiconducting and optical properties. The samples can be synthesized in the bulk, thin film, and nanoforms which show a wide range of ferromagnetism properties. Ferromagnetic semiconductors are important materials for spintronic and nonvolatile memory storage applications. Doping of transition metal elements into ZnO offers a feasible means of tailoring the band gap to use it as light emitters and UV detector. As there are controversial on the energy gap value due to change of lattice parameters we have synthesized Mn-doped ZnO nanoparticles by co-precipitation method with different concentrations to study the effect of lattice parameters changes on gap energy. The doped samples were studied by XRD, SEM, FT-IR., and UV-Vis. The XRD patterns confirm doping of Mn into ZnO structure. As Mn concentrations increases the peak due to of Mn impurity in FT-IR spectra becomes more pronounces hence confirming concentrations variation. We find from UV-Vis spectra that the gap energy due to doping concentration increases due to the Goldschmidt-Pauling rule this increase depends on dopant concentrations and increases as impurity amount increases.


2019 ◽  
Vol 807 ◽  
pp. 50-56
Author(s):  
Yun Long Zhou ◽  
Zhi Biao Hu ◽  
Li Mei Wu ◽  
Jiao Hao Wu

Using hydrated manganese sulfate and general type graphene (GR) as raw materials, Mn3O4/GR composite has been successfully prepared by the liquid phase chemical co-precipitation method at room temperature. X-ray diffraction (XRD) was used to investigate the phase structure of Mn3O4powder and Mn3O4/GR composite; The electrochemical performances of the samples were elucidated by cyclic voltammetry and galvanostatic charge-discharge test in 0.5 mol/L Na2SO4electrolyte. The results show that the Mn3O4/GR composite possesses graphene phase and good reversibility; the composite also displays a specific capacitance of 318.8 F/g at a current density of 1 A/g.


ACS Omega ◽  
2019 ◽  
Vol 4 (6) ◽  
pp. 9763-9768 ◽  
Author(s):  
Sumio Kato ◽  
Naoto Takagi ◽  
Kanji Saito ◽  
Masataka Ogasawara

2021 ◽  
Vol 99 (1) ◽  
pp. 18-23
Author(s):  
Charlie Joe Croxford ◽  
Rajpreet Kaur ◽  
Kultar Singh ◽  
Mandeep Singh Bakshi

Stable colloidal zein nanoparticles (NPs) were synthesized by using controlled precipitation method. They were made fluorescence active by incorporating a small amount of fluorescence quinolinium surfactant. The incorporation of fluorescence surfactant provided both the colloidal stability and the fluorescence ability to determine the phase transition in zein NPs under the effect of temperature variation. Maintaining colloidal stability under the effect of temperature variation is an essential aspect of zein NPs applicability as a source of vegetarian protein supplement in different food suspensions. Different techniques such as fluorescence, DLS size, zeta potential, and FTIR measurements were applied to determine the influence of temperature on the colloidal stability of zein NPs. Zein NPs undergo phase transition well above room temperature while maintaining their size in nanometer range, and the phase transition temperature decreased with the amount of zein used in the synthesis of zein NPs. The results highlighted the potential use of zein NPs as a vegetarian supplement protein in different food products.


Crystals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 250 ◽  
Author(s):  
Francesco Baldassarre ◽  
Angela Altomare ◽  
Nicola Corriero ◽  
Ernesto Mesto ◽  
Maria Lacalamita ◽  
...  

Europium-doped hydroxyapatite Ca10(PO4)6(OH)2 (3% mol) powders were synthesized by an optimized chemical precipitation method at 25 °C, followed by drying at 120 °C and calcination at 450 °C and 900 °C. The obtained nanosized crystallite samples were investigated by means of a combination of inductively coupled plasma (ICP) spectroscopy, powder X-ray diffraction (PXRD), Fourier Transform Infrared (FTIR), Raman and photoluminescence (PL) spectroscopies. The Rietveld refinement in the hexagonal P63/m space group showed europium ordered at the Ca2 site at high temperature (900 °C), and at the Ca1 site for lower temperatures (120 °C and 450 °C). FTIR and Raman spectra showed slight band shifts and minor modifications of the (PO4) bands with increasing annealing temperature. PL spectra and decay curves revealed significant luminescence emission for the phase obtained at 900 °C and highlighted the migration of Eu from the Ca1 to Ca2 site as a result of increasing calcinating temperature.


2015 ◽  
Vol 15 (10) ◽  
pp. 7988-7996
Author(s):  
Arvind H. Jadhav ◽  
Hongliang Zhang ◽  
Frank O. Agyemang ◽  
Vishwanath Hiremath ◽  
Kyuyoung Lee ◽  
...  

Electro-spun fabricated TiO2 nanofibers were prepared by simple electro-spinning method, in subsequent step silver (Ag) was deposited using precipitation method and obtained Ag-TiO2 composite nanofibers. The properties and morphology of these prepared composite nanofibers were characterized by XRD, SEM, EDX, and TGA. The prepared electro-spun composite nanofibers were applied as catalyst for the photodegradation of Congo-red under immited solar light in aqueous solution. Result reveals that, Ag loaded TiO2 composite nanofibers were effectively increased photodegradation of Congo red compared with pure TiO2 nanofibers in analogous condition. As a result, 92.0% decomposition of Congo red was obtained by using 5 wt% of Ag loaded TiO2 composite nanofibers at room temperature in short reaction time using 300 W of solar light. In addition, photodegradation of Congo red was also studied under different experimental conditions such as amount of Ag loaded in TiO2 nanofibers and contact time. Moreover, we also studied sintering effect on TiO2 nanofibers and their consequent effect on photodegradation reaction. After completion of reaction, the nanofibers can be easily separated by filtration process and reused several times without significant loss of activity. Overall study reveals that, Ag–TiO2 composite nanofibers were strongly enhanced the surface activity for the photo catalytic degradation of Congo red under ambient condition.


2012 ◽  
Vol 11 (03) ◽  
pp. 1240004 ◽  
Author(s):  
E. LINGA REDDY ◽  
A. PRABHAKARN ◽  
J. KARUPPIAH ◽  
N. RAMESHBABU ◽  
CH. SUBRAHMANYAM

Gold supported hydroxyapatite (HA) and calcium deficient hydroxyapatite (CDHA) was studied for the room temperature CO oxidation. Nanostructured gold catalyst has been prepared by deposition precipitation method, whereas HA was synthesized by microwave synthesis. Inorder to understand the influence of surface properties of HA, support HA was synthesized with different Ca/P ratios (1.67, 1.62, 1.57, 1.534 and 1.5). The gold supported catalysts were characterized by XRD, BET, ICP-OES and TEM. Typical results indicate that gold supported 1.57 HA shows higher activity compared to other HA catalysts (1.67, 1.62, 1.534 and 1.5) which may be due to the presence of optimum number of acidic and basic sites.


Sign in / Sign up

Export Citation Format

Share Document