• 한국막학회:학술대회논문집
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• 한국막학회 1992년도 추계 총회 및 학술발표회
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• pp.47-48
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• 1992

Polymer containing monomers with pendant phospholipid polar group, 2-(metha-cryloyoxy) ethyl-2-(trimethylammonium) ethyl phosphate(MTP) were synthesized and blood compatibility of the copolymers was evaluated. Good permeability of biocomponents of molecular weight below 10$^4$ through cellulosic membrane coated with the copolymer of 2-(methacryloyoxy) ethyl-2-(tri-methylammonium)ethyl phosphate, butylmethacrylate(BMA), and glycidyl methacrylate(GMA) was observed, (Fig.1).

• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.1045-1048
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• 2007

Two genes, dps encoding decaprenyl diphosphate synthase and dxs encoding 1-deoxy-D-xylulose 5-phosphate synthase, were isolated from Rhizobium radiobacter ATCC 4718. DNA sequencing analysis of the dps and dxs genes revealed an open reading frame of 1,077 bp and 1,920 bp, respectively. The heterologous expression in Escherichia coli BL21(DE3) was carried out in order to identify their functions. Recombinant E. coli BL21(DE3) harboring the dps gene produced $CoQ_{10}$ as well as $CoQ_8$ and $CoQ_9$, whereas E. coli harboring only the dxs gene produced more $CoQ_8$ compared with the wild-type E. coli. Additionally, the coexpression of dps and dxs genes in E. coli was carried out. The recombinant E. coli harboring only the dps gene produced $0.21{\pm}0.04\;mg/l$ of $CoQ_{10}$, whereas the coexpressed E. coli with dps and dxs genes produced $0.37{\pm}0.07\;mg/l$ of $CoQ_{10}$. HPLC analysis also showed that the $CoQ_{10}$ fraction (100% of the total CoQs distribution) was increased from $15.86{\pm}0.66%$ (only dps) to $29.78{\pm}1.80%$ (dps and dxs).

• 한국가스학회지
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• 제13권4호
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• pp.8-14
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• 2009

하이브리드 촉매를 이용하여 합성가스로부터 디메틸에테르(DME)를 1단계 공정으로 합성하였다. 하이브리드 촉매는 메탄올 합성반응을 위하여 Cu-ZnO-$Al_2O_3$, 메탄올 탈수반응을 위하여 aluminum phosphate 혹은 $H_3PO_4$-modified $\gamma$-alumina로 구성되었다. 제조한 촉매들은 XRD, BET, SEM, FT-IR, $NH_3$-TPD를 이용하여 특성분석을 하였다. XRD 분석을 통해 aluminum phosphate가 잘 합성되었음을 알 수 있었다. BET 분석을 통해 aluminum phosphate의 비표면적이 P/Al의 비에 따라서 달라짐을 확인할 수 있었다. 반응실험 결과 메탄올 탈수 촉매로 사용된 aluminum phosphate의 P/Al의 비가 1.2인 하이브리드 촉매에서 55%의 CO 전환율과 70%의 DME 선택도를 보여 주었다. $\gamma$-alumina를 인산으로 처리한 경우 촉매활성 감소를 막을 수 있었다. 하지만 85%의 진한인산으로 처리한 경우에는 촉매 활성 및 DME 선택도가 낮아짐을 확인할 수 있었다.

• 한국응용과학기술학회지
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• 제37권5호
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• pp.1222-1228
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• 2020

Tin bis(monohydrogen orthophosphate) monohydrate 물질의 흡착 성질에 관하여 KCl 수용액을 통하여 조사하였다. 금속이온 농도와 pH를 변화시키면서 어떻게 달라지는지 화학평형에 바탕을 두고 data를 분석하였다. 금속이온들의 흡착 data는 Langmuir 흡착식에 넣어 Langmuir 수치들을 얻는 데 사용되었다. Tin phosphate는 산성에서 이온교환 화합물로 작용하였으며, 2가의 전이금속이온에 대해 Cu⁺² > Co⁺² > Ni⁺²의 순서로 선택적 흡착성질을 나타내었다. 약한 산성 이온 교환체에서와 같이 금속이온의 교환은 tin phosphate의 선택성을 결정하는데 결정적 역할을 하였다. 모든 경우에서 흡착의 정도는 온도와 농도의 증가와 함께 증가하였다. Lnngmuir 수치들은 흡착과정 동안의 엔트로피, 엔탈피, 자유에너지 변화량같은 열역학적 함수들을 계산하는데 이용되었다.

• 청정기술
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• 제15권4호
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• pp.253-257
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• 2009

LCD 제조공정에서 배출되는 질산과 초산, 인산, 그리고 Al과 같은 금속이온을 함유한 폐에칭액으로부터 진공증발과 확산투석을 이용하여 고순도 인산을 회수하여 인산암모늄을 제조하고자 하였다. 진공증발을 이용하여 질산과 초산을 제거하였다. 진공도가 -650 mmHg인 경우에는 온도 413 K 이상에서 완전 분리되었고, 진공도가 -700 mmHg인 경우에는 온도 393 K 이상의 영역에서 완전히 분리되었다. 그리고 진공도 -730 mmHg의 경우는 온도 383 K 이상에서도 완전 분리가 가능하였다. 99%의 질산과 초산을 제거하였으며, 확산투석을 이용하여 약 97.5% 이상의 Al을 제거하였다. 이렇게 얻어진 고순도 인산과 수산화암모늄을 이용하여 일인산암모늄을 제조하는 공정에서 급격한 발열반응을 제어하고 안정된 적정조건을 도출하기 위하여 수산화암모늄의 농도, 적정 몰비, pH, 온도 등의 반응인자를 조절하여 회수율 약 90%의 일인산암모늄을 제조하였다.

• 한국토양비료학회지
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• 제49권4호
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• pp.318-326
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• 2016

Two phosphate solubilizing bacteria, Pantoea rodasii PSB-11and Enterobacter aerogenes PSB-12, were isolated from button mushroom compost and employed to assess their synergistic effect in liquid medium and on growth of green gram plants by single and co-inoculation of the strains. Co-inoculation of two strains was found to release the highest content of soluble phosphorus ($521{\mu}g\;ml^{-1}$) into the medium, followed by single inoculation of Pantoea strain ($485{\mu}g\;ml^{-1}$) and Enterobacter strain ($470{\mu}g\;ml^{-1}$). However, there was no significant difference between single inoculation of bacterial strain and co-inoculation of two bacterial strains in terms of phosphorous release. The highest pH reduction, organic acid production and glucose consumption was observed in the E. aerogenes PSB-12 single inoculated culture medium rather than those of co-inoculation. According to the plant growth promotion bioassay, co-inoculated mung bean seedlings recorded 10.6% and 10.7% higher shoot and root growth respectively compared to the control. Therefore, in concluding, co-inoculation of the strains P. rodasii and E. aerogenes displayed better performance in stimulating plant growth than inoculation of each strain alone. However, being short assessment period of the present study, we recommend in engaging further works under field conditions in order to test the suitability of the strains to be used as bio-inoculants.

• 한국해양바이오학회지
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• 제16권1호
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• pp.36-44
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• 2024

This study attempted to improve the growth of the freshwater microalgae, Parachlorella kessleri, through the sequential optimization of culture conditions. This attempt aimed to enhance the microalgae's ability to fixate atmospheric CO₂. Culture temperature and light intensity appropriate for microalgal growth were scanned using a high-throughput photobioreactor system. The supplied air flow rate varied from 0.05 to 0.3 vvm, and its effect on the growth rate of P. kessleri was determined. Next, sodium phosphate buffer was added to the culture medium (BG11) to enhance CO₂ fixation by increasing the availability of CO₂(HCO₃^-) in the culture medium. The results indicated that optimal culture temperature and light intensity were 20℃-25℃ and 300 μE/m²/s, respectively. Growth rates of P. kessleri under various air flow rates highly depended on the increase of the culture's flow rate and pH which determines CO₂ availability. Adding sodium phosphate buffer to BG11 to maintain a constant neutral pH (7.0) improved microalgal growth compared to control conditions (BG11 without sodium phosphate). These results indicate that the CO₂ fixation rate in the air could be enhanced via the sequential optimization of microalgal culture conditions.

• 상하수도학회지
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• 제31권6호
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• pp.521-527
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• 2017

Phosphorus is one of the limiting nutrients for the growth of phytoplankton and algae and is therefore one of leading causes of eutrophication. Most phosphorous in water is present in the form of phosphates. Different technologies have been applied for phosphate removal from wastewater, such as physical, chemical precipitation by using ferric, calcium or aluminum salts, biological, and adsorption. Adsorption is one of efficient method to remove phosphates in wastewater. To find the optimal media for phosphate removal, physical characteristics of media was analysed, and the phosphate removal efficiency of media (silica sand, slag, zeolite, activated carbon) was also investigated in this study. Silica sand showed highest relative density and wear rate, and phosphate removal efficiency. Silica sand removed about 36% of phosphate. To improve the phosphate removal efficiency of silica sand, Fe coating was conducted. Fe coated silica sand showed 3 times higher removal efficiency than non-coated one.

• 한국세라믹학회지
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• 제30권11호
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• pp.905-910
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• 1993

$\alpha$-tricalcium phosphate($\alpha$-TCP) powders were synthesized and their hydration properties were investigated in Tris. solution. Two kinds of $\alpha$-TCP powder samples were prepared; the one is reaction product of CaHPO4.2H2O and CaCO3, and another is that of hydroxyapatite(HAp) and $\beta$-Ca2P2O7. They were satisfied with Ca/P mole ratio 1.5 and were heated at 150$0^{\circ}C$ for 5 hours. In the hydration of $\alpha$-TCP samples the powder which was synthesized from HAp and $\beta$-Ca2P2O7 was hydrated faster than that from CaHPO4.2H2O and CaCO3. The hydration reaction of $\alpha$-TCP powder transformed rapidly into HAp accompanying setting and hardening. It was realized that the hydration reaction of $\alpha$-TCP was due to the solution-precipitation mechanism and the hydrates from the reaction were Ca-deficient HAp having funtional group HPO42-.

• Journal of Plant Biology
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• 제27권2호
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• pp.73-80
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• 1984

Palmitoyl CoA was found to inhibit corn embryo axis glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase, which were also inhibites by polyamines. However, reversal of inhibition of both enzymes by palmitoyl CoA was made by spermine. Activity of corn embryo axis protein kinase was found to increase steadily after germination. Activation and inhibition of protein kinase were made by MgCl$_2$and all polymines, respectively. Suc results suggest that fatty acid biosynthesis and lypolysis could be regulated to some extent by polyamines in corn embryo axis.