• Proceedings of the KWS Conference
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• 1994.05a
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• pp.103-105
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• 1994

• Nuclear Engineering and Technology
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• v.54 no.11
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• pp.4013-4021
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• 2022

A kind of zirconium phosphate mesoporous coordination polymer Zr-EDTMPA was successfully synthesized and characterized using XRD, FTIR, TGA, EA, SEM-EDS, and N₂ sorption-desorption measurements. The prepared Zr-EDTMPA was first employed for the removal of Co(II) from an aqueous solution, and the effects of pH, contact time, temperature, initial Co(II) concentration, reusability, and sorption mechanism were systematically investigated. The results showed that the Zr-EDTMPA is a zirconium phosphate complex formed by the coordination of EDTMPA to Zr in a molar ratio of 1:1. The sorption of Co(II) by Zr-EDTMPA was a pH-dependent, spontaneous and endothermic process, which was better fitted to the pseudo-second-order kinetic model and Langmuir isotherm model. The Zr-EDTMPA was demonstrated to have excellent reusability and presented a high sorption capacity of 73.0 mg·g^-1 for Co(II) at pH 8.0. The sorption mechanism was mainly attributed to the strong coordination between cobalt and the untapped hydroxyl functional groups on Zr-EDTMPA, which was confirmed by XPS spectra. Therefore, as a candidate sorbent with high sorption capacity and excellent reusability, Zr-EDTMPA has a great potential for the removal of Co(II) from aqueous solutions.

• Textile Coloration and Finishing
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• v.23 no.4
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• pp.257-262
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• 2011

The dish cloth requires antimicrobial activity for hygienic purpose. Until now, organic antimicrobial agents of low cost have been frequently used for the anitimicrobial finishing. However, a cleaner hving anitimicroial activity should be more durable considering consumers' ever-increasing expectation. In this study, the cleaner containing the bamboo fiber were finished with a formulation of a new zirconium-containing inorganic agent of zirconium phosphate and polyurethane binders. The optimum treatment condition was investigated. And its durability against repeated laundering cycles was assessed. The existence of Zr after the repeated laundering was verified and the antimicrobial effect did not decrease under 30 washing cycles.

• Electrical & Electronic Materials
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• v.16 no.9
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• pp.62.2-62
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• 2003

Material Characteristics of zirconium oxide thin films obtained by plasma enhanced chemical vapor deposition on p-type Si(100) substrates were investigated to explain their unable electrical properties. The films obtained without heating had polycrystalline nanograins that are mostly of a tetragonal phase under oxygen-deficient plasma conditions but transformed into a monoclinic phase with increasing $O_2$ addition in the plasma. Mostly amorphous bulk $ZrO_2$ with a relatively thicker and smoother interfacial layer was obtained from oxygen-rich plasmas, resulting in a decrease in both the overall dielectric constant and the leakage current density. the interfacial layer formed between the bulk $ZrO_2$ and Si substrate was analyzed to be zirconium silicate, which approached $SiO_2$ as its zirconium content decreased with the increasing gas phase $O_2$ content.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.102.2-102.2
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• 2012

Different layers of zirconium nitride (ZrN) and hydroxyapatite (HA) coatings were prepared on cp Ti substrate for biomedical applications. The main idea is to improve the mechanical strength as well as the biocompatibility of the coating. ZrN is known for its high mechanical strength, corrosion resistance. HA is well known for its biocompatibility properties. Hence, in this study, both materials were coated on a cp Ti substrate with bottom layer with ZrN for good bonding with substrate and the top layer with HA for induce bioactivity. Middle layer was formed by a composite of HA and ZrN. Detail analyses of the layered coatings for its structural, morphological, topographical properties were carried out. Then the mechanical property of the layered coatings was analyzed by nanoindentation. Biomimetic growths of apatite on the functionally graded coatings were determined by simulated body fluid method. This study provides promising results to use this kind of coatings in biomedical field.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.3
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• pp.194-201
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• 2016

Purpose: The purpose of this study was to evaluate of Zirconium Nitride (ZrN) coating on shear bond strength with denture base resin in Co-Cr and Ti-6Al-4V alloy. Materials and Methods: Co-Cr and Ti-6Al-4V alloy disks (10 mm in diameter, 2.5 mm in thickness; each other: n = 14) were prepared and divided with 2 groups each other by ZrN coating. After primer was applied to disks surface, denture base resin with diameter 6 mm, height 5 mm was bonded on metal disk surface. After surface roughness was measured by Profiler, shear bond strength was determined with Universal testing machine and analyzed with two-way ANOVA. The specimen surfaces and failure mode were examined using a scanning electron microscope. Results: ZrN coated groups showed significantly higher rough surface than non-coated groups (P < 0.05). Irrespective of alloy materials, shear bond strength of ZrN coated groups were lower than non-coated groups (P < 0.001). The scanning electron microscope (SEM) of ZrN coated groups showed mixed and adhesive fractures. Conclusion: ZrN coating weakened bonding strength between denture base resin and Co-Cr, Ti-6Al-4V alloy.

• Journal of the Korean Ceramic Society
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• v.44 no.10
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• pp.580-584
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• 2007

The ZrC layer instead of SiC layer is a critical and essential layer in TRISO coated fuel particles since it is a protective layer against diffusion of fission products and provides mechanical strength for the fuel particle. In this study, we carried out computational simulation before actual experiment. With these simulation results, Zirconium carbide (ZrC) films were chemically vapor deposited on $ZrO_2$ substrate using zirconium tetrachloride $(ZrCl_4),\;CH_4$ as a source and $H_2$ dilution gas, respectively. The change of input gas ratio was correlated with growth rate and morphology of deposited ZrC films. The growth rate of ZrC films increased as the input gas ratio decreased. The microstructure of ZrC films was changed with input gas ratio; small granular type grain structure was exhibited at the low input gas ratio. Angular type structure of increased grain size was observed at the high input gas ratio.

• Nuclear Engineering and Technology
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• v.35 no.5
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• pp.369-377
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• 2003

Since Zr-2.5Nb pressure tubes have a high risk for the formation of blisters during their operation in pressurized heavy water reactors, there has been a strong incentive to develop a method for the non-destructive detection of blisters grown on the tube surfaces. However, because there is little mismatch in acoustic impedance between the hydride blisters and zirconium matrix, it is not easy to distinguish the boundary between the blister and zirconium matrix with conventional ultrasonic methods. This study has focused on the development of a special ultrasonic method, so called ultrasonic velocity ratio method for a reliable detection of blisters formed on Zr-2.5Nb pressure tubes. Hydride blisters were grown on the outer surface of the Zr-2.5Nb pressure tube using a cold finger attached to a steady state thermal diffusion equipment. To maximize a difference in the ultrasonic velocity in hydride blisters and the zirconium matrix, the ultrasonic velocity ratio of longitudinal wave to shear wave, $V_L/V_S$, has been determined based on the flight time of the longitudinal echo and reflected shear echo from the outer surface of the tubes. The feasibility of the ultrasonic velocity ratio method is confirmed by comparing the contour plots reproduced by this method with those of the blisters grown on the Zr-2.5Nb pressure tubes.

• Resources Recycling
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• v.20 no.6
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• pp.56-62
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• 2011

Zirconium is used in nuclear reactors as a structural material due to its excellent corrosion resistance and to low neutron crosssection. Variation in the distribution and solubility of Zr(IV) with solution pH was obtained. Distribution of Zr(IV) containing species in HCl and $HNO_3$ solution was analyzed by considering the complex formation of Zr(IV) species with the anion of the inorganic acid. Bromley interaction parameter between $ZrO^{2+}$ and nitrate ion was estimated by using the reported data on the solvent extraction of Zr(IV) by Cyanex272 from $HNO_3$ solution. This Bromley parameter can be utilized in calculating extraction isotherm of Zr(IV) and in predicting the separation factor between Zr(IV) and Hf(IV).

• Transactions of the Korean hydrogen and new energy society
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• v.9 no.3
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• pp.101-110
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• 1998

The change of hydrogen storage characteristics by substituting zirconium for a portion of titanium in Ti-Cr-V alloys has been studied. The zirconium substitution decreased the plateau pressure and hysteresis of the PC isotherm. However, it decreased the hydrogen storage capacity and increased slopping in PC isotherm by forming $Cr_2Zr$ phase. By modifying the composition ratio of titanium to chromium, thereby suppressing the formation of $Cr_2Zr$ phase, we got an alloy having very high hydrogen storage capacity. The heat treatment of the alloys improved the flatness of plateau very much without a decrease in the maximum and the effective hydrogen storage capacities.