• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.2
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• pp.66-69
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• 2009

The compositional dependence of bismuth iron oxides and effect of La-substitutions in the structure of $BiFeO_3$ compounds were investigated, which compounds were synthesized by conventional ceramic processing. It is shown that some of bismuth iron oxides including $BiFeO_3$ show the narrow single phase region. The effect of La-doping in $BiFeO_3$ was presented as disappearance of many impurity phases of Bi-Fe-O compounds. The lower electrical resistivity was obtained as those compositions of Fe deficient region and La-doped $BiFeO_3$. The saturation magnetization of La-doped $BiFeO_3$ was increased with La content. The dielectric dispersion was also observed for those Bi-Fe-O compounds with Fe deficient and La-doped $BiFeO_3$ at low frequencies under 1 kHz.

• Journal of Pharmaceutical Investigation
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• v.16 no.4
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• pp.158-170
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• 1986

This is the article on the uses, methods of elaboration, qualitative, and quantitative evaluations, of organic and inorganic bismuth trivalent compounds. The obvious accent appears to be on the therapeutic uses. However, their interest will relate to all, for the reader looking beyond that first impression will be treated to an amazingly rich compendium of historical applications that can only prompt new questions and open up unsuspected horizons in seemingly unrelated area.

• Nuclear Engineering and Technology
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• v.51 no.3
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• pp.860-866
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• 2019

The lead element or its salts are good radiation shielding materials. However, their toxic effects are high. Due to less toxicity of bismuth salts, the radiation shielding properties of the bismuth salts have been investigated and compared to that of lead salts to establish them as a better alternative to radiation shielding material to the lead element or its salts. The transmission geometry was utilized to measure the mass attenuation coefficient (${\mu}/{\rho}$) of different salts containing lead and bismuth using a high-resolution HPGe detector and different energies (between 81 and 1333 keV) emitted from point sources of $^{133}Ba$, $^{57}Co$, $^{22}Na$, $^{54}Mn$, $^{137}Cs$, and $^{60}Co$. The experimental ${\mu}/{\rho}$ results are compared with the theoretical values obtained through WinXCOM program. The theoretical calculations are in good agreement with their experimental ones. The radiation protection efficiencies, mean free paths, effective atomic numbers and electron densities for the present compounds were determined. The bismuth fluoride ($BiF_3$) is found to have maximum radiation protection efficiency among the selected salts. The results showed that present salts are more effective for reducing the intensity of gamma photons at low energy region.

• Journal of Pharmaceutical Investigation
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• v.15 no.4
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• pp.161-178
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• 1985

• Journal of the Korean Electrochemical Society
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• v.8 no.1
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• pp.17-23
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• 2005

The electrochemical behaviors of polycrystalline silver electrodes in 8M KOH solutions containing $Bi_2O_3$ were studied under various conditions by cyclic voltammetry, potentiostatic and galvanostatic techniques as well as the morphology of the silver oxide structures by SEM. It was found that three new compounds comprising silver, bismuth, and oxygen as well as $Bi_2O_3$, $Ag_2O$ and AgO were formed during the electrochemical oxidation of silver. In addition, the potentiostatic current transients were characterized by the appearances of the first current peaks corresponding to the formation of silver oxides, and the second current peaks corresponding to the Ag-Bi-O compounds, indicating the presence of the nucleation and 3D growth mechanism, in the potential regions of $Ag_2O$ and AgO, respectively. Microscopic examinations showed that two types of silver (I) oxide morphologies are formed in the potential region of $Ag_2O$.

• Journal of the Korean Ceramic Society
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• v.28 no.3
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• pp.252-258
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• 1991

Spectral properties of europium activated intermediate compounds in the system R2O3-P2O5(R=La, Y, and Gd) are presented, including also phosphors with bismuth and vanadate sensitization. The sensitized phosphors are less efficient than unsensitized phosphors. (The ratio of oxygen to phosphorus effects the charge transfer band) Most phosphors have low efficiencies, but La3PO7 and Gd3PO7 hosts are possible for commercial luminescent materials.

• Korean Journal of Materials Research
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• v.33 no.9
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• pp.360-366
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• 2023

This study focuses on how the partial substitution of copper by nickel nanoparticles affects the electrical and structural properties of the Bi₂Ba₂Ca₂Cu_2.9Ni_0.1O_10+δ, Bi₂Ba₂Ca₂Cu_2.8Ni_0.2O_10+δ and Bi₂Ba₂Ca₂Cu_2.6Ni_0.4O_10+δ compounds. Approximate values of crystallization size and crystallization percentage for the three compounds were calculated using the Scherer, modified Scherer, and Williamson-Hall methods. A great similarity was observed in the crystal size values from the Scherer method, 243.442 nm, and the Williamson-Hall method, 243.794 nm for the second sample. At the same time this sample exhibited the highest crystal size value for the three methods. In the examination of electrical properties, the sample with 0.1 partial substitution, Bi₂Ba₂Ca₂Cu_2.9Ni_0.1O_10+δ was determined to be the best with a critical temperature of 100 K and an energy gap of 6.57639 × 10^-21 MeV. Using the SEM technique to analyze the structural morphology of the three phases, it was discovered that the size of the granular forms exceeds 25 nm. It was determined that the samples' shapes alter when nickel concentration rises. The patterns that reveal the distribution of the crystal structure also exhibit clear homogeneity.

• Journal of Pharmaceutical Investigation
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• v.5 no.3
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• pp.50-57
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• 1975

Bismuthsubgallate is a compound of indefinite composition containing bismuth and gallic acid. Because its structure was indefinite, many papers have been reported for it. But these are different one another and the relationship between the physical properties, structure and manufacturing condition has not been yet reported. In this experiment, bismuthsubgallate was prepared from bismuthsubgallate and gallic acid in an acetic medium at $65^{\circ}$, and dried at four different temperatures $30^{\circ}\;65^{\circ}\;105^{\circ}\;and\;155^{\circ}$. And some of the other relative bismuth organic compounds were prepared. To each product. elemental analysis, IR spectra and DTA, TGA curves were determined. These results revealed the followings; l. The structure of bismuthsubgallate is comfirmed as a complex form of gallomonohydroxo-bismutic acid monohydrate and its yellow colour dependent upon complex anion in the structure. 2. According to the drying temperature, the hydrate content of bismuthsubgallate is quite different: dihydrate at room temperature, mono-hydrate at. $65^{\circ}$, anhydrous at $105^{\circ}$ and decomposed partial1y oganic substance of the structure above $155^{\circ}$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.31 no.2
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• pp.117-121
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• 2018

Perovskite solar cells have received increasing attention in recent years because of their outstanding power conversion efficiency (exceeding 22%). However, they typically contain toxic Pb, which is a limiting factor for industrialization. We focused on preparing Pb-free perovskite films of Ag-Bi-I trivalent compounds. Perovskite thin films with improved optical properties were obtained by applying an anti-solvent (toluene) washing technique during the spin coating of perovskites. In addition, the surface condition of the perovskite film was optimized using a multi-step thermal annealing treatment. Using the optimized process parameters, $AgBi_2I_7$ perovskite films with good absorption and improved planar surface topography (root mean square roughness decreased from 80 to 26 nm) were obtained. This study is expected to open up new possibilities for the development of high performance $AgBi_2I_7$ perovskite solar cells for applications in Pb-free energy conversion devices.

• YAKHAK HOEJI
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• v.22 no.1
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• pp.22-26
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• 1978

The purposes of this investigation were to study the characteristic properties of bismuthoxynitrate formed by hydrolysis of bismuthnitrate according to various reaction conditions and to propose the property difference between synthesized pearl pigment and bismuthsubnitrate as pharmaceuticals by means of X-ray diffraction, IR, DTA and TGA. The pearl pigment could be obtained by reaction of bismuth nitrate-diluted nitric acid solution with cold water (5.deg.) agitation at lower pH. The pearl pigment was BiO. NO$_{3}$. 2H$_{2}$O. in composition and crystalline form was thin plate of monoclinic system and its combination with water was assumed to be hydrated hydrous form between Bi-H$_{2}$O bond. On the other hand, bismuthsubnitrate was 5BiO.4NO$_{3}$.6H$_{2}$O in composition and crystalline form was pillar of rhombic system and the bond between Bi and H$_{2}$O molecules was assumed to be hydrous form. The different properties between two compounds in structure are presumed to be caused by the hydrolysing conditions of bismuthnitrate respectively.