• Journal of Powder Materials
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• v.9 no.5
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• pp.315-321
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• 2002

Pure tantalum powder has been produced by combining Na as a reducing agent, $K_2TaF_{7}$ as feed material, KCl and KF as a diluent in a stainless steel(SUS) bomb, using the method of metallothermic reduction. The present study investigated the effect of the amount of the diluent and reaction temperature on the characteristics of tantalum powder in the production process. The temperature applied in this study $850^{\circ}C$ and the amount of the additional reductant from +5% of the theoretical amount used for the reduction of the entire $K_2TaF_{7}$. The results showed that as the amount of the diluent increased, the reaction temperature became lower because the diluent prevented a temperature rise. Also, according to the mixture ratio of the feed materials and the diluent changed from 1 : 0.25 to 1 : 2, the particle size decreased from $5\mutextrm{m}$ to $1\mutextrm{m}$ and a particle size distribution which is below 325 mesh in fined powder increases from 71% to 83%. The average size of Tantalum powder, $2-4\mutextrm{m}$, was close to that of the commercial powders($2-5\mutextrm{m}$). Also under this condition, impurities contained in the powder were within the range allowed for the commercial Ta powders.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1711-1714
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• 2010

• Korean Journal of Animal Reproduction
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• v.20 no.2
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• pp.101-109
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• 1996

This study was done to find out the methods of long-term use of liquid boar semen in 100 ml plastic bottle for artificial insemination and to investigate differences between Lactose-Egg yolk and Biitschwiler diluents according to storage temperature, and effect of final glycerol concent ration in Lactose-Egg yolk diluent. Liquid boar semen diluted with Lactose-Egg yolk diluent showed significantly higher sperm motility (p<0.05) after 0.5 and 2h incubation at 37$^{\circ}C$,than Butschwiler diluent at all storage length when it was preserved in the 5$^{\circ}C$ refrigerator. The NAR acrosome in Lactose-Egg yolk diluent a after 0.5 and 2h incubation at 37$^{\circ}C$, respectively, during preservation periods was similar to that in Biitschwiler diluent. When liquid boar semen was preserved at 15$^{\circ}C$, liquid boar semen in the Butschwiler diluent showed significantly higher percentages of sperm motility and NAR acrosome from third day to seventh than that in Lactose-Egg yolk diluent. In the effect of final glycerol concentration of liquid boar semen in the Lactose-Egg yolk diluent, the final glycerol concentration of 2% showed higer percentages of sperm motility and NAR acrosome than that of 0, 1, 3, and 5%. Farrowing rate, litter size and average pig weight at birth did not differ significantly between Lactose-Egg yolk and But schwiler diluents. As a result of this study, we found out that liquid boar semen can be stored for 6-7 days at 5$^{\circ}C$ in Lactose-Egg yolk diluent and at 15$^{\circ}C$ in Butschwiler diluent.

• Animal Bioscience
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• v.37 no.2
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• pp.203-209
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• 2024

Objective: This study aimed to assess the impact of the dilution ratio of Tris diluent, storage at 0℃, and long-distance transportation on the spermatozoa of Simmental cattle. It also validated the feasibility of the regional distribution of fresh semen. Methods: In experiment 1, semen was diluted at four dilution ratios (1:6, 1:9, 1:12, and 1:15) to determine the optimal dilution ratio of Tris diluent. In experiment 2, we assessed sperm viability, progressive motility (objectively assessed by computer-assisted sperm analyzer), and acrosome intactness in Tris dilutions kept at constant 0℃ for 1, 3, 6, 9, and 12 days. We compared them to Tianshan livestock dilutions (Commercial diluent). In experiment 3, semen was diluted using Tris diluent, and sperm quality was measured before and after long-distance transport. Artificial insemination of 177 Simmental heifers compared to 156 using Tianshan Livestock dilution. Results: The outcomes demonstrated that 1:9 was the ideal Tris diluent dilution ratio. The sperm viability, Progressive Motility, and acrosome integrity of both Tris and Tianshan dilutions preserved at 0℃ gradually decreased over time. sperm viability was above 50% for both dilutions on d 9, with a flat rate of decline. The decrease in acrosome integrity rate was faster for Tianshan livestock dilutions than for Tris dilutions when stored at 0℃ for 1 to 6 days. There was no significant difference (p>0.05) in sperm viability between semen preserved in Tris diluent after long-distance transportation and semen preserved in resting condition. The conception rates for Tris dilution and Tianshan livestock dilution were 49.15% and 46.15% respectively, with no significant difference (p>0.05). Conclusion: This shows that Tris diluent is a good long-term protectant. It has been observed that fresh semen can be successfully preserved for long-distance transport when stored under 0℃ conditions. Additionally, it is feasible to distribute semen regionally.

• Journal of the Korean Ceramic Society
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• v.35 no.7
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• pp.764-774
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• 1998

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.11
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• pp.1553-1558
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• 2002

This study was carried out to obtain informations regarding the effect of N-acetyl-D-glucosamine in the LEY (lactoseegg yolk) diluent according to incubation time in 5 ml maxi-straw and the effects of freezing rate, thawing temperature and thawing time in the LEN (lactose-egg yolk and N-acetyl-D-glucosamine) diluent on acrosome morphology and motility of frozen-thawed boar sperm. The study showed that the LEN diluent was higher post-thaw NAR (normal apical ridge) acrosome than the LEY diluent for 0.5 h incubation at 37$^{\circ}C$. However, there were no differences between the LEN and LEY diluents on post-thaw sperm motility according to incubation time. The straws frozen from 5.0 cm (20$^{\circ}C$/min) to 17.0 cm (1$^{\circ}C$/min) above the liquid nitrogen surface did not show any significant differences on post-thaw sperm motility. However, the straws frozen above 5.0 cm from the liquid nitrogen surface were higher NAR acrosome than those frozen above 17.0 cm. The post-thaw percentages of motile sperm and NAR acrosome were significantly higher (p<0.05) for the maxi-straws submerged for 40 or 45 sec in a 52$^{\circ}C$ water bath than for 30, 35, 50 or 55 sec. The mean sample temperatures of maxi-straws after 40 or 45 sec submersion were 20.7 or 26.4$^{\circ}C$. In conclusion, the sample temperature of the thawed semen was very important for post-thaw sperm survival in the LEN diluent of 5 ml maxi-straw. When the temperature of the thawed semen was 20.7$^{\circ}C$, the percentages of motile sperm and NAR acrosome were highest.

• Transactions on Electrical and Electronic Materials
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• v.14 no.6
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• pp.308-311
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• 2013

The effect of an electric field on the ac electrical treeing in various epoxy/reactive diluent systems was studied in a needle-plate electrode geometry. Diglycidyl ether of bisphenol A (DGEBA) type epoxy was used as a base resin, and 1,4-butanediol diglycidyl ether (BDGE) or polyglycol (PG) as a reactive diluent was introduced to the DGEBA system, in order to decrease the viscosity of the DGEBA epoxy system. BDGE was acted as a chain extender, and PG acted as a flexibilizer, after the curing reaction. To measure the treeing initiation time and the propagation rate, three constant alternating currents (ac) of 10, 13 and 15 kV/4.2 mm (60 Hz) were applied to the specimen, in a needle-plate electrode arrangement, at $30^{\circ}C$ of insulating oil bath. When 10 kV/4.2 mm (60 Hz) was applied, the treeing initiation time and the propagation rate in the DGEBA system were 356 min and $1.10{\times}10^{-3}$ mm/min, respectively, those in the DGEBA/BDGE system were 150 min and $1.14{\times}10^{-3}$ mm/min, respectively. Those in the DGEBA/PG system were 469 min and $1.05{\times}10^{-3}$ mm/min, respectively. As 15 kV/4.2 mm (60 Hz) was applied, the propagation rate in the DGEBA system was $5.41{\times}10^{-3}$ mm/min, and that in the DGEBA/PG system was $1.42{\times}10^{-3}$ mm/min. These values meant that PG could be used as a reactive diluent in the DGEBA system, without the deterioration of the insulation breakdown property.

• Korean Journal of Materials Research
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• v.12 no.9
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• pp.706-711
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• 2002

High-pure tantalum powder was fabricated through Na reduction process and has been produced by using $K_2$TaF$_{7}$, and KCI, KF for raw material and diluent, respectively. A raw material and diluent were charged at the hestalloy bomb by the weight rate of 1:2, 1:1, 1:0.5 and 1:0.25 each other, investigated properties of morphology, chemical composition and yield and particle size after reduced. Ta metal has been achieved by reduction of $K_2$$TaF_{7}$ 500g with 1% sodium in excess of stoichiometric amount in the charge at a reduction temperature of $850^{\circ}C$ for 3hours. According to amount of the diluent, a formation of the powder doesn't have an effect. The diluent prevented the temperature rising caused from the heat of reaction and it maintained the speed of reducing reaction. But in the mixture ratio of raw material and diluent in the 1 : 2 and 1 : 0.25, an oxide and partially not reacted K were detected. As the amount of diluent increased, the size of tantalum powder decreased. According as raw material and the mixture ratio of diluent change from 1:0.25 to 1:2, the size is decreased from 5$\mu\textrm{m}$ to 1$\mu\textrm{m}$, and a particle size distribution which is below 325 mesh in fined powder increases from 71% to 83%. In the case of average size of Tantalum powder which is the mixture ratio (1:0.5), we would get the Ta powder with grain size about 3$\mu\textrm{m}$, which come close to the average size (2~4$\mu\textrm{m}$) of tantalum powder which is used commonly in the present is Ta powder about 3$\mu\textrm{m}$.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.12
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• pp.1716-1721
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• 2006

The present study was conducted to observe the effect of osmolality of glycerolated TEST-yolk glycerol extenders on post-thawing sperm kinematics of ram spermatozoa of the native Malpura breed maintained in a semi-arid tropical environment. Good quality semen obtained from adult rams was pooled, split and diluted to 1,000 million spermatozoa per ml in complete TEST-yolk-glycerol extenders of 900, 1,200, 1,500 and 1,800 mOsm/kg osmolality. Diluted semen samples were loaded in 0.25 ml straws and cooled down to $-125^{\circ}C$ freezing temperature at the rate of $-25^{\circ}C$ per minute under controlled conditions before plunging into liquid nitrogen for storage. The thawing of straws was performed at $50^{\circ}C$ in a water bath for 10 seconds and sperm kinematics of the frozen-thawed spermatozoa were assessed by a computer-assisted sperm analysis technique. Osmolality of diluent had no significant effect on post-thawing % motility, % rapid, % medium and % slow moving frozen-thawed spermatozoa but significantly (p< 0.05) affected the % linearity and % straightness. The post-thawing % motility and % rapid motile spermatozoa were highest in samples extended in diluent of 1,500 mOsm/kg osmolality and lowest in 900 mOsm/kg. The curvilinear velocity of spermatozoa was significantly (p<0.05) higher for samples extended in 1,800 mOsm/kg, compared to those in 900 and 1,200 mOsm/kg, but the effect was not significantly different to those extended in diluent of 1,500 mOsm/kg osmolality. The study indicated that ram spermatozoa could tolerate a wide osmolality range for dilution in the complete TEST-yolk-glycerol extender for their cryosurvival. The highest recovery of motile spermatozoa following thawing was achieved in samples extended in the TEST-yolk-glycerol diluent of 1,500 mOsm/kg osmolality.

• Applied Chemistry for Engineering
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• v.9 no.5
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• pp.680-688
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• 1998

The macroreticular (MR) type glycidylmethacrylate (GMA)-divinylbenzene (DVB) copolymer (polyglycidylmethacrylate) beads (RG) were prepared by a suspension polymerization using 0~100 vol % of 2,2,4-trimethylpentane (TMP) as a diluent. Macroreticular type cation exchange resins containing phosphoric acid groups (RGP) were prepared by the reaction of GMA-DVB copolymer and poly (glycidyl methacrylate) bead (RG) with phosphoric acid in the presence of benzene. In this study, the effect of degree of crosslinking and the amount of the diluent on physical properties and adsorbability of uranium of RGP resins were investigated respectively. The chemical and physical properties of RGP resins were affected by both of the amount of the diluent and the degree of crosslinking. The effect of degree of crosslinking on the adsorbed amount of uranium for RGP resins were decreased in the order of $$RGP-10(50){\sim_=}RGP-1(50)>RGP-2(50)>RGP-5(50)>RGP-0$$. The effect of the diluent amount were as follows RGP-2(100)>RGP-2(75)>RGP-2(50)>RGP-2(30)>RGP-2(0). The crosslinking degree effect on uranium adsorbability depended on pore structure, cation exchange capability and swelling ratio. On the other hand, the effect of the diluent amount were relied on surface area and pore structure raher than cation exchange capability.