• 한국환경농학회지
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• 제11권2호
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• pp.155-162
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• 1992

수용해도가 2.53ppm인 KC-6620을 수중용출기간이 20일 정도인 입제로 제제하기 위하여 원제에 대한 용출지연효과가 가장 큰 다공성 증량제를 선발하고, PEG를 부제로 첨가한 흡착식 입제를 제제하여 실내에서 수중용출속도를 측정하였다. 1. 다공성 증량제중 KC-6620에 대하여 용출지연효과를 나타낸 것은 bentonite 소결공립이었으나 수중에 침적 20일후의 용출율이 매우 낮았다. 2. Bentonite에 pyrophyllite를 혼합하고 조립한 다음 소결시킴으로써 흡유가가 증가하였으며, 이 공립으로 제제한 KC-6620 입제의 수중용출속도도 증가하였다 BP60 입제의 경우 침적 20일후에 85% 이상의 용출율을 보여 시험한 입제중 단기용출지연제제로 가장 적합하였다. 3. BP입제는 PEG를 부제로 첨가하여 용출속도를 증가시킬 수 있었으며, PEG의 첨가비가 공립의 흡유가까지 증가할수록 용출속도도 증가하였다. 4. BP40 입제는 입제중의 유효성분함량이 높을수록 수중용출속도가 느려져서 제제농도가 용출속도를 좌우하는 가장 큰 요인이었다.

• 한국산학기술학회논문지
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• 제11권10호
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• pp.4047-4054
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• 2010

실험실 규모의 모사 실험을 통하여 해양 부영양화를 촉진하는 퇴적물의 용출 특성을 연구하였다. 즉 pH, ORP, 질소성분, 인성분 등 주요 환경인자를 분석하고 그에 따른 용출율을 계산하였다. 또한 산소발생제인 과산화칼슘을 이용하여 자연적 용출의 제어효과를 분석하였다. 산소발생제 처리에 따라 호기적 조건으로의 퇴적토 환경변화가 일어났으며 COD, $NH_3$-N의 용출율이 감소하고 질산화 촉진으로 NOx 성분은 증가하였다. 총인과 인산염인도 Ca 이온의 불용화 기작에 의거 감소하였다. 이에 따라 퇴적토의 용출로 인한 해양 부영양화 억제 방법론을 정립하고자한다.

• Journal of Pharmaceutical Investigation
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• 제27권2호
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• pp.99-108
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• 1997

To evaluate the feasibility of mucosal delivery of thyrotropin releasing hormone (TRH) through various mucosae, enzymatic degradation and stabilization of TRH in the nasal, rectal and duodenal extracts of rabbits were studied. TRH in the extracts was assayed by HPLC and its degradation was found to follow apparent first-order kinetics. The residual concentrations of TRH in the mucosal extracts of nasal, rectal and duodenal segments after 24 hr of incubation were found to be $65.1({\pm}1.1),\;19.7({\pm}2.7)$ and 0%, and in the serosal extracts, $65.6({\pm}5.5),\;75.2({\pm}1.1)$ and $68.7({\pm}1.4)%$, respectively. This result suggests that there is a significant difference in the activity of TRH-degrading enzymes among the sites of administration. The inhibition of TRH degradation in the mucosa extracts was kinetically investigated using various additives such as thimerosal, benzalkonium chloride, disodium edetate, ${\sigma}-phenanthroline$, dithiothreitol and dithioerythritol, and $IC_{50}$ values of inhibitors were calculated. The results obtained showed that thimerosal (0.5 mM) and benzalkonium chloride (0.141 mM) protected TRH from the enzymatic degradation in all the mucosa extracts more than 95% after 24 hr of incubation.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제3권3호
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• pp.129-138
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• 2022

Reintroduction programs have been promoted across the world to recover and rehabilitate endangered birds through ex situ captive breeding and releasing to the nature. The ultimate aims of these reintroduction programs are recovery of sustainable populations in natural habitats. To ensure the success of the reintroduction programs, it is necessary to examine the followings in order to increase the success rate of releasing along with the development of captive breeding techniques: 1) Adequate habitat provision, 2) adaptability of captive-bred individuals, 3) survivability of released individuals, and 4) social interest and will. Before releasing captive-bred individuals, it should be reviewed whether there are habitats in which the limiting factor is removed, and assessed their long-term safety. The quantity and quality of the released individuals must be considered to increase the chances for mate selection, maintain genetic diversity, and acquire the ability to adapt to the wild. The release method must be decided in consideration of characteristics of the target habitats and individuals, and rational means such as careful observation, evaluation, and feedback must be provided throughout the release process. For the long-term success of recovery projects, social awareness, sustainable support, and related experts are needed. Satisfying these criteria can help to increase the success rates of reintroduction programs. For the bird reintroduction program in the future, the feasibility of the methods and procedures must be closely reviewed before starting.

• 한국작물학회지
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• 제65권4호
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• pp.477-484
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• 2020

This study was conducted to investigate the effects of slow-releasing fertilizer and sowing date on waxy corn propagated through double cropping without tillage. "Mibaek 2" was sown for first cropping on March 25^th, April 5^th, and April 15^th, and for second cropping on July 5^th, July 15^th, and July 25^th in 2018-2019. In order to save labor, slow-releasing fertilizer was utilized only one time before sowing. The accumulated temperature from sowing to silking was about 590-700℃. It took 65-77 days when "Mibaek 2" was sown in early April, but the one sown in early July took 42-52 days. In the first cropping, the culm length and ear length caused by the sowing date had no statistical significance, but the kernel set length was the highest at 123 cm in the sowing district on April 5^th. The weight of marketable ears was the highest at 100%, in addition to soil testing-based recommended fertilization. Meanwhile, in the second cropping, culm length, ear length, and yield were less compared to the first cropping. The culm length, kernel set length, ear length, and seed set length decreased as sowing date was delayed. The number and yield of marketable ears were the highest at 100%, in addition to soil testing-based recommended fertilization like in the first cropping. It has been found that securing yield by July 15^th to finish the second seeding of the crop in the central part of Korea is advantageous. These results of this study will be helpful to farmers for the double cropping of waxy corn cultivation and management.

• Fisheries and Aquatic Sciences
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• 제27권6호
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• pp.366-378
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• 2024

Application of commercial hormone failed to promote breeding in certain Pangasius species due to the differences of gonadotropin-releasing hormone specific peptide with species-specific bioactivities. Gonadotropin-releasing hormone (GnRH) is a hypothalamic decapeptide in the reproductive system that plays a crucial role in the regulation of reproductive processes. This study was performed to determine and analyse the GnRH genes from commercially important Pangasius sp., Pangasianodon hypophthalmus and Pangasius nasutus. The GnRH1 and GnRH2 genes were amplified and cloned into TOPO vector, followed by phylogenetic analysis of a complete open reading frame (ORF) of GnRH genes. The GnRH1 and GnRH2 genes of P. hypophthalmus and P. nasutus were detected at 300 bp and 360 bp, encoded for 81 and 87 amino acids, respectively. Amino acid sequence identities revealed high homology of P. hypophthalmus and P. nasutus GnRH1 and GnRH2 genes in comparison with other fish and vertebrates. Phylogenetic tree showed that fish from various families were aggregated into a group of the same order due to their highest identity similarities. It revealed that the vertebrate formed clusters and are grouped according to their GnRH decapeptide and GnRH-associated peptide (GAP) region, indicating a close relationship among GnRH decapeptide and GAP in different vertebrate species.

• 한국토양비료학회지
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• 제40권5호
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• pp.377-382
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• 2007

완효성을 부여하려는 물질의 외부에 광물입자를 이용하여 피복형 구조체를 제조하고 이의 방출조절능력을 카리비료에 대한 용출실험을 통해 평가하였다. 황산칼륨을 구형의 펠릿으로 제조하고 이의 표면에 평균입도 $13.0{\mu}m$와 $27.4{\mu}m$인 두 가지 장석분말을 이용하여 구조체를 제조하였다. 구조체의 두께와 소성하는 온도를 달리하여 펠릿을 제조하고 용출실험을 통해 구조체의 완효성 발현능력을 평가하였다. 칼륨의 용출은 burst effect효과가 커서 초기 용출율이 높았는데, 소성온도가 낮고 구조체가 얇은 시료에서 크게 나타났다. $1{\sim}55{\mu}m$의 입도를 갖는 장석 보다 $1{\sim}130{\mu}m$의 입도를 갖는 장석에 의한 구조체가 더 높은 충진율에 의해 용출속도를 늦출 수 있었다. 용출속도는 약 7일부터 정상상태의 용출속도를 보이기 시작하였고 용출패턴은 펠릿에 남아있는 칼륨의 농도에 비례하는 first order kinetic의 패턴을 나타내었다. 평균입도 $27.4{\mu}m$인 장석으로 1~2.6mm두께의 피복형 구조체를 만들어 $1050^{\circ}C$에서 소성한 팰릿의 경우에는 40일의 용출율이 약 43%를 나타내었다.

• Bulletin of the Korean Chemical Society
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• 제32권11호
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• pp.4021-4026
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• 2011

Functions of the luteinizing hormone releasing hormone (LHRH) and its induced release by divalent metal ions have received great attention because this neurotransmitter subsequently regulates the secretion of luteinizing hormone (LH). Metal-LHRH complexes were synthesized by addition of various Cu(II),Ni(II),Zn(II) ions into LHRH in order to understand how the induced release of LHRH is possible. The degree of complexation was monitored by $^1H$, $^{13}C$-NMR chemical shifts, and final products were identified by Mass spectrometry. Solutionstate structure determination of Zn(II)-LHRH out of metal-complexes was accomplished by using NMR and NMR-based distance geometry (DG). Interproton distance information from nuclear Overhauser effect spectroscopy was utilized for structure determination. Structure obtained in this study has a cyclic conformation exhibiting a specific ${\alpha}$-helical turn with residue numbers His[2]-Leu[7] out of 10 amino acids. Comparison of chemical shifts and EPR studies of Ni(II),Cu(II)-LHRH complexes exhibit that these metal complexes have 4-coordination geometry.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 추계 학술논문 발표대회
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• pp.77-78
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• 2018

Form-work is a must for construction work. In order to secure the best condition of the form surface and to increase the number of times, the form releasing agent is applied during the process of the form-work. The base oil of the form release agent which has been used already uses the oil which directly or indirectly affects the natural environment and the concrete. In this study, the basic study on the form release agent for concrete was carried out only for the effect of adhesion. The adhesive force of the tile is measured by the mortar to determine the change of the releasing agent and the adhesive strength.

• 산업공학
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• 제19권2호
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• pp.97-105
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• 2006

In this paper, based on the process analysis of a semiconductor company, a lot order release procedure (input regulation) is developed for a semiconductor company. The major characteristic of the order release procedure in this paper is to consider the workloads of machines which are obtained from a virtual lot flows by the dispatching rule at machines in the shop of the semiconductor company. The objective is to minimize the cycle time and to obtain other good performances. A simulation is performed in order to evaluate the order release procedure in this paper.