• Title/Summary/Keyword: Copper(I)

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Mechanistic Investigation of the Copper(I)-Catalyzed Trifluoromethylthiolation Using Sulfonyl Hypervalent Iodonium Ylide as the SCF3 Source: A DFT Study

  • Park, Yoonsu;Jung, Yousung
    • Proceeding of EDISON Challenge
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    • 2014.03a
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    • pp.337-346
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    • 2014
  • Trifluoromethylthiol functional group(이하 -SCF3)은 약학적으로 유용한 물질이다. 이 연구는 최근 개발된 Shibata의 Direct trifluoromethylthiolation reaction의 반응 메커니즘을 계산화학적으로 평가했다. 반응 메커니즘은 크게 Carbene formation, Rearrangement, Electrophilic SCF3 reagent generation 세 단계로 나눌 수 있다. 각 과정에 대해 구조에 대한 full optimization이 진행되었고, 특히 alpha-carbene sulfonyl species의 thermal rearrangement에 관한 첫번째 계산화학적 평가가 이루어졌다.

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The study of laser processing parameter for $\mu$-BGA cutting ($\mu$-BGA 절단을 위한 레이저 가공 파라미터 연구)

  • Baek, kwang-yeol;Lee, cheon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.652-655
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    • 2001
  • In this paper, I have studied minimization of the kerf-width and surface burning which are occurred after the singulation process of multi layer $\mu$-BGA( thickness 1.1 mm, 0.9 mm) with a pulsed Nd:YAG( = 532 nm, repetition rate = 10 Hz) laser. The thermal energy of a pulsed Nd:YAG laser is used to cut the copper layer. I have studied are minimization of the surface burning and kerf-width using a photo resist, $N_2$blowing and polyester double sided tape as a cutting parameter. The $N_2$blowing reduces a laser energy loss by debris and suppresses a surface carbonization. Also, I have studied characters of cutting with a choice of side of laser beam incidence. The SEM(Scanning Electron Microscope), non-contact 3D inspector and high-resolution microscope are used to measure kerf width and surface state. The optimum value of 1.1 mm $\mu$-BGA singulation is 524 $\mu$m that is reduced kerf width of 60 % with $N_2$blowing. And I obtained reduction of carbonization of 68 % with a polyester double side tape in 0.9 mm $\mu$-BGA. I used laser intensity of 1.91$\times$10$^{6}$ / $\textrm{cm}^2$ in this study.

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Influence of Level of Dietary Inorganic and Organic Copper and Energy Level on the Performance and Nutrient Utilization of Broiler Chickens

  • Das, T.K.;Mondal, M.K.;Biswas, P.;Bairagi, B.;Samanta, C.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.1
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    • pp.82-89
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    • 2010
  • An experiment was conducted to determine the influence of dietary inorganic (copper sulfate) and organic (copper proteinate) forms of copper and energy level on performance and nutrient utilization of broiler chickens. Two hundred day-old commercial Vencobb broiler chicks were purchased and randomly distributed to 20 cages of 10 birds each. These replicates were randomly assigned to one of five treatments in a (($2{\times}2$)+1) factorial arrangement. These two factors were sources of Cu ($CuSO_{4}$ vs. Cuproteinate) and dose of Cu supplements (200 mg and 400 mg/kg dietary dry matter) and the control (no supplemental Cu). After the starter period (up to 3 weeks), from d 22 onwards another factor i.e. energy at two levels (2,900 vs. 2,920 kcal/kg diet) was introduced with the previous factorial arrangements by subdividing each replicate into two equal parts, for two energy levels, without disturbing the dose and source of Cu supplement. Cu-salt supplementation linearly increased (p<0.01) live weight (LW), live weight gain (LWG) and feed conversion ratio (FCR) at 3 weeks, whereas cumulative feed intake (CFI) was unaffected (p>0.05). LWG and FCR were higher (p<0.01) in Cu-proteinate supplemented birds compared to $CuSO_{4}$ supplementation. A linear dose response (p<0.01) of Cu was found for the performance of broiler chickens. Birds having a higher energy level in the finisher stage increased (p<0.01) LWG and FCR. Cumulative feed intake was similar (p>0.05) across the groups up to the 5th week. Cu-proteinate increased performance of broiler chickens compared to $CuSO_{4}$. Dose of supplemental Cu-salt irrespective of source showed a linear response (p<0.01) for performance. Supplementation of Cu-proteinate increased metabolizability of DM (p<0.01), NFE (p<0.05), total carbohydrate (p<0.01) and OM (p<0.01) at the starter period. Increased dose of Cu-salt linearly increased (p<0.01) metabolizability of DM, CP, CF, NFE and OM. Higher energy level in the diet improved DM (p<0.05), EE (p<0.01), NFE (p = 0.01), total carbohydrate (p<0.01) and OM (p<0.01) metabolizability. Cu-proteinate supplementation showed better nutrient utilization compared to CuSO4. Dose of Cu linearly increased DM, CP, EE, NFE, total carbohydrate and OM metabolizability. CF metabolizability was unaffected (p>0.05) among the treatments. In conclusion, dietary supplementation of Cu-salt more than the requirement may improve performance and nutrient utilization in broiler chickens even with a high energy finisher diet. Cu-proteinate showed better performance and nutrient utilization compared to $CuSO_{4}$.

The Study on Natural Dyeing with Artemisia (쑥을 이용한 천연염색에 관한 연구)

  • Im, Myeong-Eun;Yu, Hye-Ja;Lee, Hye-Ja
    • Journal of the Korean Society of Clothing and Textiles
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    • v.21 no.5
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    • pp.911-921
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    • 1997
  • Recently the interest in natural dyeing has been increased because of the color clarity, natural grace and reactionism in fashion. Indigo dyeing, safflower dyeing and Gal-ott in Cheju-Do become generally known, so the study about the natural dyeing is continued with national intrust and support. In this study, 1 used artemisia for various dyeing tests because we can get it easily. 1 tested the dyeability in wool as well as cotton and silk with wormwood in natural dyeing material. I also dyed nylon with the same material for the comparison of the molecular structure. The mercerization and the chitosan treatment were done in cotton to improve the low dyeability in the natural dyeing. The result of this study are as follows; We have to dye repeatedly to get deep color in natural dyeing, and mordant treatment brought good result in color difference and dyeing fastness. 1. Compared with silk, wool and nylon, the dyeability of cotton was the worse. The color difference of cotton was 18.81 without mordants , and 24.05 with mordant. The dyeability of cotton was much increased by mordants such as potassiumdichromate, copper sulfate, iron sulfate and salt water. The color of cotton was turned into yellow-green in potassium dichromate and yellow-green with deep green in copper sulfate. The mercerization and the chitosan treatment of cotton made the improvement in color, dyeability, laundering fastness, abrasion fastness. 2. The color difference of silk was 3 times as high as cotton. It showed the similar degree with the chitosan treated-cotton. That is to say, silk had good dyeability because it contains amino group and carboxyl group. The dyebility of silk was increased by a mordant such as iron sulfate, potassium dichromate and salt water, Drycleaning fastness showed 5 grade, abrasion-fastness was high over 4~5 grade and sunlight fastness showed 1 grade in all case. 3. The color difference of wool was the best among four fabrics because of 18 kinds of amino acids. It is considered that the sulfate of wool has the polarity and help metal- mordants get the better dyeability such as potassium dichromate, iron sulfate, copper sulfate, and aluminum chloride. The color was reddish-green in potassium dichromate, yellow.greenin iron sulfate and copper sulfate, and yellow in the rest mordants. Drycleaning fastness of wool showed over 4~5 grade, abrasion fastness 5 grade. Sunlight-fastness 1 grade. 4. The dyeability of nylon was almost same because of the similar molecular structure with silk. The clarity of color was poor. The color was yellow-green in copper sulfate and yellow in the rest mordants. Laundering fastness and abrasion-fastness of nylon was good. Sunlight- fastness represented 1 grade.

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Genetic Environments of Hydrothermal Copper Deposits in Ogsan Mineralized Area, Gyeongsangbukdo Province (경북 옥산지역 열수동광상의 성인연구)

  • Choi, Seon-Gyu;Choi, Sang-Hoon;Yun, Seong-Taek;Lee, Jae-Ho;So, Chil-Sup
    • Economic and Environmental Geology
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    • v.25 no.3
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    • pp.233-243
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    • 1992
  • Ore mineralization of the Hwanghak copper deposit in the Ogsan area occurred in three stages of quartz (stage I and II) and calcite (stage III) veining along fissures in Early Cretaceous sedimentary rocks. Ore minerals are pyrite, pyrrhotite, chalcopyrite (dominant), sphalerite, hematite, galena, and Ag-, Pb-, and Bi-sulfosalts. These were deposited during the first stage at temperatures between $370^{\circ}C$ and < $200^{\circ}C$ from fluids with salinities between 0.5 and 7.6 equiv. wt. % NaCl. There is evidence of boiling and this suggests pressures of less than 180 bars during the first stage. Equilibrium thermodynamic interpretation accompanying with mineral paragenesis and fluid inclusion data indicates that copper precipitation in the hydrothermal system occurred due to cooling and changing in chemical conditions ($fs_2$, $fo_2$, pH). Gradual temperature decrease from $350^{\circ}$ to $250^{\circ}C$ of ore fluids by boiling and mixing with less-evolved meteoric waters mainly led to copper deposition through destabilization of copper chloride complexes. Sulfur isotope values of sulfide minerals decrease systematically with paragenetic time from calculated ${\delta}^{34}S_{H_2S}$ values of 8.2 to 4.7‰. These values, together with the observed change from sulfide-only to sulfide-hematite assemblages and fluid inclusion data, suggest progressively more oxidizing conditions, with a corresponding increase of the $sulfate/H_2S$ ratio of hydrothermal fluids. Measured and calculated hydrogen and oxygen isotope valutls of ore-forming fluids suggest meteoric water dominance, approaching unexchanged meteoric water values.

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Effect of Copper on Plasma Ceruloplasmin and Antioxidant Ability in Broiler Chickens Challenged by Lipopolysaccharide

  • Song, Zhigang;Zhu, Lixian;Zhao, Tong;Jiao, Hongchao;Lin, Hai
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.10
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    • pp.1400-1406
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    • 2009
  • The effects of dietary copper (Cu) supplementation in broiler chickens challenged with a single injection of Salmonella typhymurium lipopolysaccharide (LPS) on the antioxidant capacity and plasma levels of ceruloplasmin (Cp) were evaluated. The broiler chickens were provided with a basal diet or diets supplemented with 8 and 50 mg/kg Cu from 1d of age. At 25d of age, 48 chickens with similar body weight were selected from each diet. Half of the chickens in each dietary treatment were injected intraperitoneally (i.p.) with LPS (1 mg/kg body weight). The other half was injected with saline, serving as the control. Body weight gain and feed consumption were significantly suppressed by LPS challenge during the first 12-h after injection, regardless of dietary Cu levels. Feed efficiency was reduced by LPS injection during the 72-h experimental period. Dietary Cu levels had no significant effect (p>0.05) on the plasma ceruloplasmin concentrations in chickens injected with saline. In contrast, high dietary level of Cu elevated plasma Cp levels in chickens with LPS challenge. Short-term LPS challenge had no significant effect on the antioxidant ability of broilers, as indicated by superoxide dismutase, ferric reducing/antioxidant power and the thiobarbituric acid reacting substances in the plasma. The result suggests that high dietary Cu level (as much as 50 mg/kg supplementation) is favorable for coping with short-term LPS challenge through upregulating plasma Cp levels.

Studies on Activity and Characteristics of CuO/ZnO/TiO2 Catalysts for Methanol Steam Reforming (메탄올 수증기 개질반응을 위한 CuO/ZnO/TiO2계 촉매의 활성 및 특성에 관한 연구)

  • Koh, Hyoung-Lim;Kim, Tae-Won;Lee, Jihn-Koo;Kim, Kyung-Lim
    • Applied Chemistry for Engineering
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    • v.9 no.7
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    • pp.956-960
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    • 1998
  • Cu-Zn and Cu-Zn-Ti catalysts for the steam reforming of methanol were prepared. This reaction was carried out at atmospheric pressure, $250^{\circ}C$, steam/methanol molar ratio 1.5, and contact time 0.1 g-cat.hr/mL-feed. In case of the catalyst with 3 mol% of $TiO_2$, the activity was superior to that of catalysts without $TiO_2$. The reaction products were mainly hydrogen and carbon dioxide. It was found that catalytic activity was not related to specific surface area but affected by metallic copper area which was measured by $N_2O$ decomposition and increased with the addition of $TiO_2$ content. XPS and XRD showed that the oxidation state of zinc was not changed during reaction, but oxidation states of copper existed in Cu(0) or Cu(I).

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Aluminum, Copper and Lead as Shielding Materials in 6 MeV Electron Therapy (6 MeV 전자선 치료 시 차폐물질로서 알루미늄, 구리, 납)

  • Lee, Seung-Hoon;Cha, Seok-Yong;Lee, Sun-Young
    • The Journal of the Korea Contents Association
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    • v.14 no.2
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    • pp.457-466
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    • 2014
  • During irradiation of lesions in cancer treatment with high energy electrons, normal tissue and critical organs are protected by the shielding material. Scattered radiation that generated the shielding materials affect the depth dose and atomic number. Therefore, we want to examine secondary particles and the scattered photons through calculation and its associated analysis, and compare the measurement for the aluminum, copper, and lead shielding substance of which thickness has 95% charge reduction. Dose change rate which effected scattering radiation was found to be +0.88% for material thickness, +0.43% for atomic number, and +19.70%, +15.20%, +12.40% for measurement, +25.00%, +15.10%, +13.70% for calculation on the aluminum, copper, and lead materials of which thickness has 95% charge reduction, respectively, As a result, we found that scattering rate was dependent on thickness than atomic number. In the dose increasing rate, scattered electrons are more important than scattered photon. For the above mentioned reasons, I think that high atomic number materials should be applied to reduce scattered radiation that generated with thickness effect.