scholarly journals Raman and Fluorescence Spectroscopy of CeO2, Er2O3, Nd2O3, Tm2O3, Yb2O3, La2O3, and Tb4O7

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Jianlan Cui ◽  
Gregory A. Hope
Keyword(s):  
Rare Earth ◽  
Energy Levels ◽  
Fluorescence Emission ◽  
Chemical Properties ◽  
Rare Earth Oxide ◽  
Raman Shift ◽  
Laser Sources ◽  
Induced Changes ◽  
Physical And Chemical ◽  
Good Agreement

To better understand and ascertain the mechanisms of flotation reagent interaction with rare earth (RE) minerals, it is necessary to determine the physical and chemical properties of the constituent components. Seven rare earth oxides (CeO2, Er2O3, Nd2O3, Tm2O3, Yb2O3, La2O3, and Tb4O7) that cover the rare earth elements (REEs) from light to heavy REEs have been investigated using Raman spectroscopy. Multiple laser sources (wavelengths of 325 nm, 442 nm, 514 nm, and 632.8 nm) for the Raman shift ranges from 100 cm−1to 5000 cm−1of these excitations were used for each individual rare earth oxide. Raman shifts and fluorescence emission have been identified. Theoretical energy levels for Er, Nd, and Yb were used for the interpretation of fluorescence emission. The experimental results showed good agreement with the theoretical calculation for Er2O3and Nd2O3. Additional fluorescence emission was observed with Yb2O3that did not fit the reported energy level diagram. Tb4O7was observed undergoing laser induced changes during examination.

scholarly journals Pengaruh Berbagai Parameter Ekstraksi dalam Pemisahan Unsur Tanah Jarang dengan Metode Emulsion Liquid Membrane (ELM)

2021 ◽  
Vol 17 (1) ◽  
pp. 1
Author(s):  
Handias Meilinda ◽  
Novi Noviyanti ◽  
Anni Anggraeni ◽  
Diana Hendrati ◽  
Husein H Bahti
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Liquid Membrane ◽  
Chemical Properties ◽  
Membrane Phase ◽  
Emulsion Liquid Membrane ◽  
Phase Concentration ◽  
Stirring Time ◽  
Feed Phase ◽  
Physical And Chemical

<p>Unsur Tanah Jarang (UTJ) adalah 15 elemen kelompok lantanida, ditambah skandium dan itrium yang termasuk kelompok aktinida. UTJ memiliki banyak manfaat di berbagai bidang. Sifat fisik dan kimia yang mirip antar UTJ membuatnya sulit dipisahkan sehingga pemisahan UTJ menarik dipelajari dengan berbagai macam metode, salah satunya adalah dengan menggunakan <em>Emulsion Liquid Membrane </em>(ELM). ELM merupakan metode pemisahan yang dikembangkan dari ekstraksi pelarut terdiri dari tiga fase, yaitu fase eksternal (fase umpan) yang berisi UTJ yang akan dipisahkan, fase internal (fase pengupasan), dan fase membran. Fase membran berisi surfaktan sebagai penstabil dan ligan yang akan membentuk kompleks dengan UTJ pada antarmuka fase umpan dan membawanya berdifusi ke dalam fase pengupasan. ELM merupakan metode efektif untuk pemisahan karena tahap ekstraksi dan pengupasan (<em>stripping</em>) terjadi secara bersamaan dalam satu tahap dan fase membrannya dapat digunakan kembali. Pemisahan UTJ menggunakan metode ELM dengan berbagai ligan, seperti D2EHPA, Cyanex 572, P204, dan (RO)2P(O)OPh-COOH dipengaruhi oleh berbagai parameter, seperti konsentrasi ligan, pH fase umpan, waktu pengadukan ekstraksi, kecepatan pengadukan ekstraksi, rasio fase umpan, konsentrasi fase pengupasan, konsentrasi surfaktan, dan konsentrasi fase umpan. Parameter tersebut diseleksi untuk mendapatkan kondisi optimum sehingga meningkatkan efisiensi ekstraksi dan pengupasan yang berbeda.</p><p><strong>Effect of Various Parameters in Separation of Rare Earth Elements using the Emulsion Liquid Membrane (ELM) Method. </strong>Rare Earth Elements (REEs) are 15 elements of the lanthanide group, plus scandium and yttrium, which belong to the actinide group. REEs have many benefits in various fields. Similar physical and chemical properties between REEs make it difficult to separate, thus REEs separation is interesting to study by various methods, one of which is by using an emulsion liquid membrane (ELM). ELM is a method developed from solvent extraction consisting of three phases: the external phase (feed phase) which contains REEs to be collected, the internal phase (stripping phase), and the membrane phase. The membrane phase contains surfactants as stabilizers and ligands which will form complexes with REEs in the feed phase and are designed to diffuse into the stripping phase. ELM is an effective method to involve because extraction and stripping occur together in one glass and the membrane phase can be reused. Separation of REEs using the ELM method with various ligands, such as D2EHPA, Cyanex 572, P204, and (RO)2P(O)OPh-COOH influenced by various parameters, such as ligand concentration, feed phase pH, extraction stirring time, extraction stirring speed, feed phase ratio, stripping phase concentration, surfactant concentration, and feed phase concentration. These parameters are selected to obtain optimum conditions thereby increasing the efficiency of different extraction and stripping.</p><p> </p>

Nano Crystallite ZrO2, La2O3 and CeO2: Synthesis, Characterization and their Properties

2013 ◽  
Vol 209 ◽  
pp. 212-215
Author(s):  
A.K. Patel ◽  
A.R. Umatt ◽  
B.S. Chakrabarty
Keyword(s):  
Rare Earth ◽  
Surface Area ◽  
Gas Adsorption ◽  
Chemical Properties ◽  
Rare Earth Oxide ◽  
Combustion Method ◽  
Rare Earth Oxides ◽  
Precipitation Method ◽  
Reaction Conditions ◽  
The Rare Earth

It is well known that a minor addition of rare earth oxides can provide a beneficial effect towards various catalytic reactions. Use of rare earth oxide in different applications could improve commercial productivity in an affordable way. Among the rare earth oxides, ZrO2, La2O3 and CeO2 are very interesting due to their various characteristics showing a large range of applications in organic reactions. The changes in the molecular properties of materials at the nano scale level greatly enhance their physical properties as well as chemical properties and activity. Due to the extremely small size of the particles, an increased surface area is provided to the reactant enabling more molecules to react at the same time, thereby speeding up the process. In this work, the enhancement in the catalytic activity of these nano structured rare earth oxides has been studied under different reaction conditions. Nano crystalline ZrO2, La2O3 and CeO2 samples were synthesized using precipitation method and optimum reaction conditions have been established; whereas the corresponding bulk samples were synthesized by combustion method. The identification of phase and crystalline size of synthesized oxides have been done by X-ray diffraction, the band gape of these three oxides in both the forms has been analyzed by UV absorbance and surface area has been determined by gas adsorption analysis (BET). Moreover their different properties and the activity of nano crystallite oxides have also been compared with their bulk counterparts. Even the activity of ZrO2 is also compared with the rare earth oxides La2O3 and CeO2.

Defect Structure of Ion-Irradiated Amorphous SiO2

1997 ◽  
Vol 30 (5) ◽  
pp. 618-622 ◽  
Author(s):  
Y. Eyal ◽  
R. Evron ◽  
Y. Cohen
Keyword(s):  
Ion Irradiation ◽  
Chemical Properties ◽  
Atomic Displacement ◽  
Amorphous Sio2 ◽  
X Ray Scattering ◽  
Scattering Centers ◽  
Radiation Induced ◽  
Induced Changes ◽  
Physical And Chemical ◽  
And Chemical Properties

Uniformly enhanced small-angle X-ray scattering intensities of amorphous SiO2, measured following irradiation with 320 keV H+ and He+ beams, are shown to be correlated, irrespective of the incident ion, with the O and Si cumulative displacement yields. Damage by both beams originated primarily from nuclear stopping but, under H+-ion irradiation, contributions from ionization processes were significant as well. At low beam fluences, the irradiated structure is compatible with the presence of stable radiation-induced interstitial-like O and Si atoms and complementary O and Si vacancy-like sites. There is no evidence for recovery near room temperature of the modified structure to the pre-irradiated state or for formation of colloidal-size scattering centers, such as gas bubbles or voids. Thus, ion-irradiation-induced changes in physical and chemical properties of silica seem to be due to the effect of the preserved primary atomic displacement damage.

scholarly journals Graphene Oxide and Polyethyleneimine Cooperative Construct Ionic Imprinted Cellulose Nanocrystals Aerogel for Selective Adsorption of Dy(III)

2021 ◽  
Author(s):  
Xudong Zheng ◽  
Wen Sun ◽  
Ang Li ◽  
Bin Wang ◽  
Rong Jiang ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Rare Earth ◽  
Cellulose Nanocrystals ◽  
Selective Adsorption ◽  
Chemical Properties ◽  
Regeneration Ability ◽  
Maximum Adsorption Capacity ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract Because of dysprosium's unique physical and chemical properties and limited supply, the price of rare earth dysprosium has been high in recent years. Therefore, the study of the method of high efficiency selective separation of dysprosium has the double value of scientific research and practical economy. In this paper, we used periodic cellulose nanocrystals as the basic structure, polyethylenimine and graphene oxide were introduced, combined with imprinting technology, to construct porous imprinted aerogel and use it for selective adsorption of Dy(III). The physical and chemical properties were characterized by SEM, TEM, FT-IR and TGA. It was proved that both polyethylenimine and graphene oxide were crosslinked effectively with cellulose nanocrystals. Adsorption experiments showed that the composite imprinted aerogel could selectively adsorb dysprosium effectively, and the maximum adsorption capacity for Dy(III) was 36.495 mg g− 1. The reproducibility experiment showed that aerogel had good regeneration ability. In conclusion, cellulose nanocrystals aerogel, which is environmentally friendly, efficient and repeatable, is expected to provide a new direction for the recovery of rare earth elements.

scholarly journals Critical Compilations of Atomic Energy Levels

1984 ◽  
Vol 86 ◽  
pp. 207-207
Author(s):  
J. Sugar ◽  
W.C. Martin ◽  
J. Reader ◽  
A. Musgrove ◽  
C. Corliss
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Reference Data ◽  
Energy Levels ◽  
Atomic Energy ◽  
Atomic Energy Levels ◽  
Physical And Chemical

We have been publishing new compilations of energy levels for single elements in all stages of ionization as each is completed. Those now in print in the Journal of Physical and Chemical Reference Data are helium (1973), sodium (1981), magnesium (1980), aluminum (1979), silicon (1983), potassium (1979), calcium (1979), scandium (1980), titanium (1979), vanadium (1978), chromium (1977), manganese (1977), iron (1982), cobalt (1981) and nickel (1981). A volume containing atomic energy levels of all rare earth elements was issued in 1978. We have now updated our compilations for the iron period (K through Ni, 235 spectra), which will be published in a single volume.

Physical and chemical properties of the rare earth antimonides Ln5Sb3

1986 ◽  
Vol 120 (2) ◽  
pp. 281-285 ◽  
Author(s):  
M.N Abdusaljamova ◽  
V.D Abulchaev ◽  
R.Z Levitin ◽  
A.S Markosijan ◽  
V.F Popov ◽  
...  
Keyword(s):  
Rare Earth ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
And Chemical Properties ◽  
The Rare Earth

scholarly journals Determination of physiochemical properties of Gum Arabic as a suitable binder in emulsion house paint

2016 ◽  
Vol 5 (1) ◽  
pp. 67-78
Author(s):  
Ali L. Yaumi ◽  
Ahmed M. Murtala ◽  
Habiba D. Muhd ◽  
Fatima M. Saleh
Keyword(s):  
Chemical Properties ◽  
Gum Arabic ◽  
Acacia Senegal ◽  
Physiochemical Properties ◽  
Binding Strength ◽  
Wide Range ◽  
Percentage Concentration ◽  
Physical And Chemical ◽  
Good Agreement

Gum Arabic “GA” is an organic adhesive produced from a tree called named Acacia Senegal. The gum has a wide range of industrial uses, especially in areas of feeds, textiles, and pharmaceuticals. It is used as emulsifier and serves mostly as stabilizer in both cosmetic and food products which contains oil water interface. GA sample was collected, formulated and prepared into various concentrations ranging from 20%w/v to 85%w/v. The quality and applicability of well characterized materials are directly related to their physical and chemical properties. From the physiochemical analysis, the result revealed that all the samples were slightly acidic (pH ranging from 4.81-6.41). This range is in good agreement with reported pH values for gum arabic and other Acacia gums by several authors. . The binding strength increases as the number of days increases for example in sample F (50%w/v) gum Arabic concentration increases from 1.5 in the 1st day to 1.97 in the 28th day. The samples prepared are denser than water which indicates that the density increases as the percentage concentration of the samples increases and the relative density of the gum solution is independent on time. The binding strength of sample G (75%w/v) gum concentration compared well to that of polyvinyl acetate (PVA). International Journal of Environment Vol. 5 (1) 2016,  pp: 67-78

scholarly journals Flow cytometry: a literature review

2016 ◽  
Vol 14 (2) ◽  
pp. 221 ◽  
Author(s):  
Paolo Ruggero Errante ◽  
Pâmela Carolina Cruz Ebbing ◽  
Francisco Sandro Menezes Rodrigues ◽  
Renato Ribeiro Nogueira Ferraz ◽  
Neusa Pereira Da Silva
Keyword(s):  
Biological Sciences ◽  
Flow Cytometry ◽  
Literature Review ◽  
Light Beam ◽  
Fluorescence Emission ◽  
Chemical Properties ◽  
Unspecific Binding ◽  
Basic And Applied Research ◽  
Physical And Chemical ◽  
And Chemical Properties

Introduction: flow cytometry is a technique that employs an optical-electronic detection apparatus to analyze the physical and chemical properties of microscopic particles suspend in a liquid medium. Objective: to review the literature in search of the main studies that used flow cytometry as the main methodology. Method: Articles were selected according to their impact factor in the Journal of Citation Reports. Literature review: a light beam is direct to a continuous flow of suspended particles marked with fluorescent substances. The light is scattered differently from the beam by the particles and is captured by sensors in line and perpendicular to the light beam. These microscopic particles are conjugated with fluorescent substances that, once excited, emit light of lower frequency than the light source. The emitted light is captured by sensors and the particles are analyzed according to fluctuations in brightness of each detector and/or fluorescence emission. The result of this process is the formation of images in real time for each cell fluorescence, scattering and transmission of light. A major problem of flow cytometry is to determine whether a subset of cells labeled with fluorochrome-conjugated monoclonal antibodies is positive or negative. Gains compensation should be determined and applied correctly, and controls should be conducted concisely with the adoption of a biological control, isotype control or Fluorescence Minus One (FMO). None of these controls are considered ideal, and must be chosen according the number of different labeling done, rarity of molecule expression on surface or intracellularly in certain cell subsets, overlap of wavelengths or unspecific binding of the fluorochrome-conjugated antibodies. Conclusion: due to its great potential, flow cytometry has been expanded to diverse fields of biological sciences, and is routinely used in clinical diagnostic, biotechnology, and basic and applied research.

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