• Journal of the Korean institute of surface engineering
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• v.40 no.4
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• pp.175-179
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• 2007

An Fe-Ni-Co based superalloy Incoloy 909 (Incoloy 909) has been used for gas turbine engine component material. This alloy is susceptible to high temperature oxidation and corrosion because of the absence of corrosion resistant Cr. For the improvement of durability of the component of Incoloy 909 aluminizing-chromate coating by pack cementation process has been investigated at relatively low temperature of about $550^{\circ}C$ to protect the surface microstructure and properties of Incoloy 909 substrate. As a previous study to aluminizing-chromate coating by pack cementation of Incoloy 909, the optimal aluminizing process has been investigated. The size effects of source Al powder and inert filler $Al_O_3$ powder and activator selection have been studied. And the dependence of coating growth rate on aluminizing temperature and time has also been studied. The optimal aluminizing process for the coating growth rate is that the mixing ratio of source Al powder, activator $NH_4Cl$ and filler $Al_O_3$ are 80%, 1% and 19% respectively at aluminizing temperature $552^{\circ}C$ and time 20 hours.

• Journal of Welding and Joining
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• v.28 no.3
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• pp.49-58
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• 2010

Various alloy system, such as Cu-Sn-Ti, Cu-Ag-Ti, and Ni-B-Cr-based alloy are used for the brazing of diamond grits. However, the problem of the adhesion strength between the diamond grits and the brazed alloy is presented. The adhesion strength between the diamond grits and the melting filler alloy is predicted by the contact angle, thereby, instead of diamond grit, the study on the wettability between the graphite and the brazing alloy has been indirectly executed. In this study, Cu-13Sn-12Ti filler alloy was manufactured, and the contact angles, the shear strengths and the interfacial area between the graphites (diamond grits) and braze matrix were investigated. The contact angle was decreased on increasing holding time and temperature. The results of shear strength of the graphite joints brazed filler alloys were observed that the joints applied Cu-13Sn-12Ti alloy at brazing temperature $940^{\circ}C$ was very sound condition indicating the shear tensile value of 23.8 MPa because of existing the widest carbide(TiC) reaction layers. The micrograph of wettability of the diamond grit brazed filler alloys were observed that the brazement applied Cu-13Sn-12Ti alloy at brazing temperature $990^{\circ}C$ was very sound condition because of existing a few TiC grains in the vicinity of the TiC layers.

• Journal of Fisheries and Marine Sciences Education
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• v.23 no.4
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• pp.662-672
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• 2011

This study was investigated to obtain basic data which can be applied to processing of canned seasoned kwamaegi. Commercial Kwamaegi was cut into $2{\times}3cm$ lengths, filled 90 g into can (301-3) and added with 60 g water before precooking for 10 min. at $100^{\circ}C$. The precooked Kwamaegi was packed into the can, and added with 60 g seasoning sauces, which was prepared by mixing soy sauce 23%, monosodium glutamate (MSG) 2%, sorbitol 2%, sesame oil 1%, vinegar 2%, starch syrup 17%, sake 5%, water 48%. The cans were sealed using a vacuum seamer and then sterilized for various Fo values (Fo 8~12 min.) in a steam system retort at $121^{\circ}C$. The factors such as pH, VBN, amino-N, total amino acid, free amino acid, color value (L, a, b), texture profile, TBA value, mineral, sensory evaluation and viable bacterial count of the canned seasoned Kwamaegi produced with various sterilization condition(Fo 8~12 min.) were measured. There was no remarkable difference between sterilization conditions and sensual characteristics. The results showed that the product sterilized at Fo 8 min. was the most desirable because this condition is most economical.

• Journal of Technologic Dentistry
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• v.33 no.4
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• pp.349-357
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• 2011

Purpose: In this study, for the reasons of observing the changes when using bonding agent with Ni-Cr alloy and Co-Cr alloy and using VM13 and Vintage MP ceramic which have the disparity in coefficient of thermal expansion, it is carried out to evaluate the characteristics of the bonding agent through the analysis of the interface between metal and ceramic and the analysis of bond strength by variable. Methods: The surface treatment was performed on the two kinds of alloy(Ni-Cr alloy and Co-Cr alloy) specimens, which were sandblasted and were treated with bonder application. The metal-ceramic interfaces were analyzed with EPMA in order to ionic diffusion, and the shear test was performed. Results: As a result of observation of metal-ceramic interfacial properties, it was observed that Cr atoms were spread from the alloy body to the ceramic floor in the specimen of Group B. It was also seen that Cr, W atoms were spread from the alloy body to the ceramic floor in the specimen of Group S. In consequence of observing Shear bond strength, it was calculated that the specimen of BSV was 27.75(${\pm}11.21$)MPa, BSM was 27.02(${\pm}5.23$)MPa, BCV was 30.20(${\pm}5.99$)MPa, BCM was 27.94(${\pm}10.76$)MPa, SSV was 20.83(${\pm}2.58$)MPa, SSM was 23.98(${\pm}3.94$)MPa, SCV was 32.32(${\pm}4.68$)MPa, and SCM was 34.54(${\pm}10.63$)MPa. Conclusion: In the metal-ceramic interface of Bellabond plus sample group, diffusion of Cr atoms was incurred and diffusion of C Cr atoms and W atoms in the sample group of $Starloy{(R)}\;C$ was observed. Using bonding agent showed the higher bond strength than using the sand blasting treatment. In the Bellabond plus alloys, the specimen group with the use of binding materials showed higher shear bond strength, but didn't show statistically significant differences (p>0.05). In the $Starloy{(R)}\;C$ alloys, the specimen group with the use of binding materials showed higher shear bond strength and statistically significant differences(p<0.05). In terms of VM13 ceramic, it was in the Bellabond plus alloys that the high shear bond strength was showed, but there's no statistically significant differences(p>0.05). In terms of Vintage MP ceramic, it was in the $Starloy{(R)}\;C$ alloys that the high shear bond strength was showed and statistically significant differences(p<0.05). Metal-ceramic to fracture of the shear strength measurements and an analysis of all aspects of military usage fracture of the composite, respectively.

• Journal of Welding and Joining
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• v.30 no.5
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• pp.64-69
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• 2012

Sn-Bi eutectic alloy has been widely used as one of the key solder materials for step soldering at low temperature. The Sn-58Bi solder paste containing chloride flux was adopted to compare with that using the chloride-free flux. The paste was applied on the electroless nickel-immersion gold (ENIG) surface finish by stencil printing, and the reflow process was then performed at $170^{\circ}C$ for 10 min. After reflow, the solder joints were aged at $125^{\circ}C$ for 100, 200, 300, 500 and 1000 h in an oven. The interfacial microstructures were obtained by using scanning electron microscopy (SEM), and the composition of intermetallic compounds (IMCs) was analyzed using energy dispersive spectrometer (EDS). Two different IMC layers, consisting of $Ni_3Sn_4$ and relatively very thin Sn-Bi-Ni-Au were formed at the solder/surface finish interface, and their thickness increased with increasing aging time. The wettability of solder joints was investigated by wetting balance test. The mechanical property of each aging solder joint was evaluated by the ball shear test in accordance with JEDEC standard (JESD22-B117A). The results show that the highest shear force was measured when the aging time was 100 h, and the fracture mode changed from ductile fracture to brittle fracture with increasing aging time. On the other hand, the chloride flux in the solder paste did not affect the shear force and fracture mode of the solder joints.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.3
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• pp.314-322
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• 2008

This study was carried out to assess aerobic stabilized waste sludge as liquid fertilizer for the growth of cucumber, cabbage and chrysanthemum. Sludge was pretreated with NaOH(40 meq/L) at 40$^{\circ}C$ for 330 min. The number of fecal coliforms in batch test sludge fertilizer was more efficiently reduced than those in continuous one, maybe due to longer SRT. All produced fertilizer belonged to class B according to US EPA requirement at least. Among 6 heavy metals regulated in Korea, As, Cd and Hg were not detectable in plant amended with fertilizer whereas the concentration of Cr, Cu and Pb in plant was less than 10 mg/kg dw. However, Zn and Ni, which were restricted in other country, but not in Korea, were detected in most amount of 118 mg/kg and 15.7 mg/kg, respectively. Furthermore, based on dry weight of plant, digested sludge(5.4 mg, dw) functioned as better fertilizer rather than activated sludge (4.3 mg, dw), much more fertile when those sludge was pretreated(1.24 mg, dw) compared to untreated one(1.12 mg, dw). But its fertility was 60$\sim$80% of commercial fertilizer and accumulation of Zn, Ti and Cr in plant was founded. Therefore, it could be concluded that sludge-fertilizer can be used for flower unlimitedly, but for edible plant limitedly as additive fertilizer.

• Bulletin of the Korean Chemical Society
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• v.14 no.6
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• pp.687-691
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• 1993

Complexation of $Cd^{2+},\;Pb^{2+}\;and\;Hg^{2+}$ ions with four cryptands were studied by potentiometry and solution calorimetry in various weight percent methanol-aqueous solvent at 25${\circ}$C under $CO_2$free nitrogen atmosphere. The stabilities of the complexes were dependent on the cavity size of macrocycles. The $Hg^{2+}$ ion stability constants are higher than those of $Cd^{2+}\;and\;Pb^{2+}$ ion. All the cryptands formed complexes having 1 : 1 (metal to ligand) mole-ratio except for $Hg^{2+}-L_1$ (cryptand 1,2b: 3,5-benzo-9,14,17-trioxa-1,7-diazabicyclo-(8,5,5) heptadecane) and $Cd^{2+}-L_2$ (cryptand 2,2b: 3,5-benzo-10,13,18,21-tetraoxa-1,7-diazabicyclo (8,5,5) eicosane) complexes. $Hg^{2+}-L_1$ complex was a sandwitch type, and the $Cd^{2+}-L_2$ complex showed two stepwise reactions. Thermodynamic parameters of the $Cd^{2+}-L_2$ complex were $6.08(log\;K_1)$, -7.28 Kcal/mol $({\Delta}H_1)$, and $4.78\;(log\;K_2)$, -4.62 Kcal/mol $({\Delta}H_2)$, respectively, for 1 : 1 and 2: 1 mole-ratio. The sequences of the selectivity were increased in the order of $Hg^{2+}\;>Pb^{2+}\;>Cd^{2+}$ ion for $L_3\;and\;L_4$ macrocycles, and the $L_2$-macrocycle has a selectivity for $Cd^{2+}$ ion relative to $Zn^{2+},\;Ni^{2+},\;Pb^{2+}\;and\;Hg^{2+}$ ions. Thus, it is expected that the $L_2$ can be used as carrier for seperation of the post transition metals by macrocycles-mediated liquid membrane because $L_2$ is not soluble in water, and the difference of stability constants of the metal complexes with $L_2$ are large as compared with the other transition metal complexes. The $^1H\;and\;^{13}C-NMR studies indicated that the nitrogen atoms of cryptands have greater affinity to the post transition metal ions than the oxygen atoms, and that the planarities of the macrocycles were lost by complexation with the metal ions because of the perturbation of ring current of benzene molecule attached to macrocycles and counter-anions.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.2
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• pp.131-144
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• 2006

For the purpose of preparing the fundamental data on working environment of small scale manufacturing industries and preventing the occupational diseases of workers in these industries, authors surveyed the status of working environment to several chemical substances and physical agents by types of industry and types of process in the small scale manufacturing industries with less than five workers in Gimhae including 235 workplaces, 14 types of industry and 25 types of process from January 2002 to December 2004. This measurement method was work environment measurement method (established in Ministry of Labor, Korea), analytical methods (2nd Ed.) of Occupational Safety and Health Administration (OSHA) and manual of analytical methods (4th Ed.) of National Institute for Occupational Safety and Health (NIOSH) and collected data was analyzed by using SPSS 10.0 for windows, the results were as follows: 1. Noise generated in 14 types of industry and 22 types of process. an actual level of mean exposure (90.7 dB(A)) exceeded threshold limit values (TLVs) in manufacture of other transport equipment. An actual level of mean exposure (90.2dB) exceeded TLVs in the process of wire-drawing and 90.4dB in the process of wire-stranding. 2. Dusts of type I, II, III were generated in 9 types of industry and 8 types of process. Its mean concentration did not exceed TLVs. 3. Heavy metals (Pb, Mn, Cr, Ni) were generated in 7 types of industry and 7 types of process. Its mean concentration did not exceed TLVs. 4. 16 kinds of organic solvents were generated in 11 types of industry and 6 types of process. Its mean concentration did not exceed TLVs. As the above results, chemical substances and physical agents were generated in the several different types of industry and process of the manufacturing industry with less than five workers, and only mean level of noise was exceeded TLVs. In case of exceeding threshold limit values, improvement of work environment is actively needed, and work environment management should be performed continuously for prevention of an occupational diseases and work related diseases.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.8
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• pp.1080-1088
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• 2013

Our previous results showed that kisspeptin-10 (Kp-10) injections via intraperitoneal (i.p.) once daily for three weeks notably promoted the egg laying rate in quails. In order to investigate the mechanism behind the effects of Kp-10 on enhancing the egg laying rate in birds, this study focused on the alternations of lipids synthesis in liver after Kp-10 injections. 75 female quails (22 d of age) were allocated to three groups randomly, and subjected to 0 (control, Con), 10 nmol (low dosage, L) and 100 nmol (high dosage, H) Kp-10 injections via i.p. once daily for three weeks, respectively. At d 52, quails were sacrificed and sampled for further analyses. Serum $E_2$ concentration was increased by Kp-10 injections, and reached statistical significance in H group. Serum triglyceride (TG) concentrations were increased by 46.7% in L group and 36.8% in H group, respectively, but did not reach statistical significance, and TG contents in liver were significantly elevated by Kp-10 injections in a dose-dependent manner. Serum total cholesterol (Tch) concentrations significantly decreased in H group, while in H group the hepatic Tch content was markedly increased. The level of non-esterified fatty acid (NEFA), apolipoprotein A1 and B (apoA1 and apoB) were not altered by Kp-10 injections. The genes expression of sterol regulatory element binding protein-1 (SREBP-1), fatty acid synthetase (FAS), apolipoprotein VLDL-II (apoVLDL-II), cholesterol $7{\alpha}$-hydroxylase (CYP7A1) and vitellogenin II (VTG-II) were significantly up-regulated by high but not low dosage of Kp-10 injection compared to the control group. However, the expression of SREBP-2, acetyl-CoA carboxylase ($ACC_{\alpha}$), malic enzyme (ME), stearoyl-CoA (${\Delta}9$) desaturase 1 (SCD1), apolipoprotein A1 (apoA1), fatty acid binding protein 2 (FABP2), 3-hydroxyl-3-methyl glutaryl-coenzyme A reductases (HMGCR), estrogen receptor ${\alpha}$, ${\beta}$($ER{\alpha}$ and ${\beta}$) mRNA were not affected by Kp-10 treatment. In line with hepatic mRNA abundance, hepatic SREBP1 protein content was significantly higher in H group. Although the mRNA expression was not altered, the content of $ER{\alpha}$ protein in liver was also significantly increased in H group. However, SREBP-2 protein content in liver was not changed by Kp-10 treatment. In conclusion, exogenous Kp-10 consecutive injections during juvenile stage significantly advanced the tempo of egg laying in quails, which was associated with the significant elevation in hepatic lipids synthesis and transport.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5081-5086
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• 2012

Background: The liver is one of the most common metastatic sites of breast cancer, hepatic metastases developing in 6%-25% of patients with breast cancer and being associated with a poor prognosis. The aim of this study was to analyze the survival and clinical characteristics of patients with hepatic metastases from breast cancer of different molecular subtypes and to investigate the prognostic and predictive factors that effect clinical outcome. Methods: We retrospectively studied the charts of 104 patients with breast cancer hepatic metastases diagnosed at Sun Yat-sen University Cancer Center from December 1990 to June 2009. Subtypes were defined as luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) enriched, triple-negative (TN). Prognostic factor correlations with clinical features and treatment approaches were assessed at the diagnosis of hepatic metastases. Results: The median survival time was 16.0 months, and the one-, two- three-, four-, five-year survival rates were 63.5%, 31.7%, 15.6%, 10.8%, and 5.4%, respectively. Median survival periods after hepatic metastases were 19.3 months (luminal A), 13.3 months (luminal B), 18.9 months (HER2-enriched), and 16.1 months (TN, P=0.11). In multivariate analysis, a 2 year-interval from initial diagnosis to hepatic metastasis, treatment with endocrine therapy, and surgery were independent prognostic factors. Endocrine therapy could improve the survival of luminal subtypes (P=0.004) and was a favorable prognostic factor (median survival 23.4 months vs. 13.8 months, respectively, P=0.011). Luminal A group of patients treated with endocrine therapy did significantly better than the Luminal A group of patients treated without endocrine therapy (median survival of 48.9 vs. 13.8 months, P=0.003). Conclusions: Breast cancer subtypes were not associated with survival after hepatic metastases. Endocrine therapy was a significantly favorable treatment for patients with luminal subtype.