• 제목/요약/키워드: molecular distribution

검색결과 1,397건 처리시간 0.033초

CATALYTIC DEGRADATION OF WASTE HIGH-DENSITY POLYETHYLENE INTO LIQUID PRODUCT

  • Lee, Kyong-Hwan;Shin, Dae-Hyun;Suh, Jeong-Kwon
    • Environmental Engineering Research
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    • 제10권2호
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    • pp.54-61
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    • 2005
  • Liquid-phase catalytic degradation of waste high-density polyethylene (HDPE) over ZSM-5 (powder type (PW)) and ZSM-5+binder (granule type (GR)) has been investigated with a stirred semi-batch operation at 400°C. Two ZSM-5 catalysts with a different crystal size were synthesized and also each ZSM-5 (25%) Catalyst was mixed with a same binder (kaolin: silica sol: alumina = 55%:10%:10%). The performance of prepared catalysts that has different physicochemical properties was discussed with the cumulative amount distribution, molecular weight distribution and also paraffin, olefin, naphthene and aromatic (PONA) distribution in liquid product. These liquid product quality and distributions were changed depending on the physicochemical properties of the catalyst. Moreover, the characteristic of ZSM-5 in the catalyst was strongly influenced on the activity and PONA distribution in liquid product.

Administration Route Dependency of Distribution of Distribution pf PEGylated Recombinant Human Tumor Necrosis Factor Binding Protein (rhTNFbp-PEG20K dimer) following i.v. and s.c. Injection

  • Kim, Dong-Chool;Duane C. Bloedow
    • Archives of Pharmacal Research
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    • 제17권5호
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    • pp.381-382
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    • 1994
  • Administration route dependency on the distribution of PEGylated recombinant human turor necrosis factor binding protein (rhTNFbp-PEG20K dimer) was observed following a subcutaneous (sc) and an intravenous (iv) administrationin rats. ehTNFbp-PEG20K dimer is composed of two rhTNGbp molecules (molecular weight 18, 278 daltons each) joined by polyethylene glycol 2000(PEG30K). The steady state distribution volume of rhTNFbp-PEG20K was 55 m/kg and 359 ml/kg following the i.v. and s.c. administrations, respectively. These results suggest that the distribution of ehTNFbp-PEG20K is limited within the cpillary space after i.v. administration, while rhTNFbp-PEG20K can distribute into a space (35.9% of body weight) which is between extracellylar space and total body water. A lymphatic absorption may paly a role in the distribution of rhTNFbp-PEF20K dimer following the sc administration. The present study suggests that the administration route of a lartge protein molecule should be determined depedning upon target sites.

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플라즈마발생기의 이온분율 측정 장치 설계 및 제작 (The design and fabricationt for ion fraction measurement of plasma generator)

  • 이찬영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.368-368
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    • 2008
  • Ion implantation has been widely developed during the past decades to become a standard industrial tool. To comply with the growing needs in ion implantation, innovative technology for the control of ion beam parameters is required. Beam current, beam profile, ion fractions are of great interest when uniformity of the implant is an issue. Especially, it is important to measure the spatial distribution of beam power and also the energy distribution of accelerated ions. This energy distribution is influenced by the proportion of mass for ion in the plasma generator(ion source) and by charge exchange and dissociation within the accelerator structure and also by possible collective effects in the neutralizer which may affect the energy and divergence of ions. Hydrogen atom has been the object of a good study to investigate the energy distribution. Hydrogen ion sources typically produce multi-momentum beams consisting of atomic ion ($H^+$) and molecular ion ($H_2^+$ and $H_3^+$). In the beam injector, the molecular ions pass through a charge-exchanges gas cell and break up into atomic with one-half (from $H_2^+$) or one-third (from $H_3^+$) according to their accelerated energy. Burrell et al. have observed the Doppler shifted lines from incident $H^+$, $H_2^+$, and $H_3^+$ using a Doppler shift spectroscopy. Several authors have measured the proportion of mass for hydrogen ion and deuterium using an ion source equipped with a magnetic dipole filter. We developed an ion implanter with 50-KeV and 20-mA ion source and 100-keV accelerator tube, aiming at commercial uses. In order to measure the proportion of mass for ions, we designed a filter system which can be used to measure the ion fraction in any type of ion source. The hydrogen and helium ion species compositions are used a filter system with the two magnets configurations.

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Molecular Phylogenetic Diversity and Spatial Distribution of Bacterial Communities in Cooling Stage during Swine Manure Composting

  • Guo, Yan;Zhang, Jinliang;Yan, Yongfeng;Wu, Jian;Zhu, Nengwu;Deng, Changyan
    • Asian-Australasian Journal of Animal Sciences
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    • 제28권6호
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    • pp.888-895
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    • 2015
  • Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and subsequent sub-cloning and sequencing were used in this study to analyze the molecular phylogenetic diversity and spatial distribution of bacterial communities in different spatial locations during the cooling stage of composted swine manure. Total microbial DNA was extracted, and bacterial near full-length 16S rRNA genes were subsequently amplified, cloned, RFLP-screened, and sequenced. A total of 420 positive clones were classified by RFLP and near-full-length 16S rDNA sequences. Approximately 48 operational taxonomic units (OTUs) were found among 139 positive clones from the superstratum sample; 26 among 149 were from the middle-level sample and 35 among 132 were from the substrate sample. Thermobifida fusca was common in the superstratum layer of the pile. Some Bacillus spp. were remarkable in the middle-level layer, and Clostridium sp. was dominant in the substrate layer. Among 109 OTUs, 99 displayed homology with those in the GenBank database. Ten OTUs were not closely related to any known species. The superstratum sample had the highest microbial diversity, and different and distinct bacterial communities were detected in the three different layers. This study demonstrated the spatial characteristics of the microbial community distribution in the cooling stage of swine manure compost.

미토콘드리아 cytochrome b 유전자 염기서열 분석에 의한 극동지역 송사리의 계통과 지리적 분포의 상관관계 (Molecular Phylogeny and Distribution of Far Eastern Oryzias latipes Based on Mitochondrial Cytochrome b Gene Sequence)

  • 어재영;유정하;강태욱;김무상;김창배
    • 한국어류학회지
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    • 제18권1호
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    • pp.12-19
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    • 2006
  • 본 연구에서는 극동지역 Oryzias latipes의 지리적 분포와 미토콘드리아 cytochrome b (cyt b)의 유전적 다양성과의 관계를 밝히기 위해 전국 9개의 지역에서 53개체를 채집하여 얻은 cyt b 염기서열과 GenBank에 등록되어있던 117개의 데이터를 종합하여 이를 142개의 haplotype으로 새로이 변환하였고, 이의 계통수를 작성 분석하였다. 분석 결과 극동지역 송사리는 3개의 haplogroup (A, B, C)으로 나뉘어지며, haplogroup A는 남한의 남한아지역을 중심으로 남한 전역에 분포하며, haplogroup B는 중국와 남한의 서한아지역에 걸쳐 분포하며, haplogroup C는 일본에만 분포하였다. Haplogroup A는 haplogroup B와 한반도내에서 지리적으로 가깝게 분포하고 있으나 계통적으로는 상당한 거리를 가지고 뚜렷하게 구별되었다. haplotype의 분지양상은 선행된 연구결과와 거의 일치하였다.

호화전분의 쌍축형 압출성형에서 전분액화 및 체류시간 분포 (Starch Liquefaction and Residence Time Distribution in Twin-Screw Extrusion of ${\alpha}$-Starch)

  • 김성욱;이승주
    • 한국식품과학회지
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    • 제41권4호
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    • pp.369-373
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    • 2009
  • 전분액화에 호화찰옥수수전분가 쌍축형 압출성형의 원료로 직접 사용되었다. 그 액화 효과와 체류시간분포를 분석하였다. 내열성 ${\alpha}$-amylase(Bacillus licheniformis로부터 분리)를 함께 첨가하여 사용하였다. 전분액화는 환원당측정, gel permeation chromatography(GPC), 주사전자현미경을 통하여 분석하였다. 배럴온도와 수분함량이 높을수록 환원당 함량은 증가하였고, 호화전분의 경우 생전분보다 더 많은 환원당이 생성되었다. GPC에서 호화전분의 사용에 의한 저분자화 효과는 뚜렷하지 않았으나, 효소 첨가없이 압출성형하는 경우에는 일부 효과가 있는 것으로 나타났다. 주사전자현미경의 미세구조에서는 호화전분을 쓸 경우 그 표면이 더 불규칙하고 침식되는 것을 관찰할 수 있었다. 종합적으로 호화전분의 사용이 전분액화에 효과가 있음을 알 수 있었다. 체류시간분포에서는 호화전분을 원료로 할 경우 그 분산도가 커지는 것으로 나타났다. 이는 호화전분은 압출성형의 흐름이 원만하지 않은 것을 의미하였으나, 배럴온도와 수분함량을 증가시킴에 따라 그 분산도를 감소시킬 수 있음을 알 수 있었다.

바이오디젤 윤활성 향상 메커니즘 (Mechanism of Lubricity Improvement by Biodiesels)

  • 임영관;이재민;김종렬;하종한
    • Tribology and Lubricants
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    • 제32권3호
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    • pp.95-100
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    • 2016
  • As an alternative fuel, biodiesel has excellent lubricating property. Previously, our research group reported that the properties of biodiesels depended on their composed molecular structure. In this study, we investigate lubricity and the mechanism of lubricity improvement of synthesized biodiesel molecules. We synthesize four types of biodiesel components from fatty acid via fisher esterification and soybean biodiesel from soybean oil via transesterification in high yield (92-96%). We analyze the lubricity of the five 5 types of biodiesel using HFRR (high frequency reciprocating rig). We estimate that the mechanism of lubricity is relevant to the molecular structure and structure conversion of biodiesel. The test results indicate that the longer the length of molecules and the higher the content of olefin, the better the lubricity of the biodiesel molecules. However, the wear scar size of the first test samples’ do not show a regular pattern with the wear scar size of the second test samples’. Moreover, we investigated the structure conversion of the biodiesels by using GC-MS for the recovered biodiesel samples from the HFRR test. However, we do not detect structure conversion. Thus, we conclude that the lubricity of biodiesel depends on how effectively solid adsorption and boundary lubrication occurs based on the size of the molecule and the content of olefin in the molecule. In addition, HFRR test condition in not sufficient for Diels-Alder cyclization of biodiesel components.

Comparison of Positron Emission Tomography(PET) imaging-based initial in vivo pharmacokinetics by administration routes of [18F]FDG

  • Yiseul Choi;Jang Woo Park;Eun Sang Lee;Ok-Sun Kim;Hye Kyung Chung
    • 대한방사성의약품학회지
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    • 제7권2호
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    • pp.99-103
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    • 2021
  • In this study, the initial in vivo pharmacokinetic changes according to the routes of drug administration were investigated using bioimaging techniques. The purpose of this study was to quantify the degree of distribution of each major organ in normal mice over time by acquiring Positron Emission Tomography/Computed Tomography images while administering routes F-18 fluorodeoxyglucose such as intravenous, intraperitoneal and per oral, a representative diagnostic radiopharmaceutical. Dynamic Positron Emission Tomography images were acquired for 90 minutes after drug administration. Radioactivity uptake was calculated for major organs using the PMOD program. In the case of intravenous administration, it was confirmed that it spread quickly and evenly to major organs. Compared to intravenous administration, intraperitoneal administration was about three times more absorbed and distributed in the liver and intestine, and it was showed that the amount excreted through the bladder was more than twice. In the case of oral administration, most stayed in the stomach, and it was showed that it spread slowly throughout the body. In comparison with intravenous administration, it was presented that the distribution of kidneys was more than 9 times and the distribution of bladder was 66% lower. Since there is a difference in the initial in vivo distribution and excretion of each administration method, we confirmed that the determination of the administration route is important for in vivo imaging evaluation of new drug candidates.

Promoter Analysis of the Cell Surface-abundant and Hypoviral-regulated Cryparin Gene from Cryphonectria parasitica

  • Kim, Myoung-Ju;Kwon, Bo-Ra;Park, Seung-Moon;Chung, Hea-Jong;Yang, Moon-Sik;Churchill, Alice C.L.;Van Alfen, Neal K.;Kim, Dae-Hyuk
    • Molecules and Cells
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    • 제26권5호
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    • pp.496-502
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    • 2008
  • Cryparin, encoded as a single copy gene (Crp) of the chestnut blight fungus Cryphonectria parasitica, is the most abundant protein produced by this fungus. However, its accumulation is decreased remarkably in C. parastica strains containing the double-stranded (ds) RNA virus Cryphonectria hypovirus 1. To characterize the transcriptional regulatory element(s) for strong expression and viral regulation, promoter analysis was conducted. Serial deletion of the Crp promoter region resulted in a step-wise decrease in promoter activity, indicating a localized distribution of genetic elements in the cryparin promoter. Promoter analysis indicated two positive and a repressive cis-acting elements. Among them, the promoter region between nt -1,282 and -907 appeared to be necessary for hypoviral-mediated down-regulation. An electrophoretic mobility shift assay (EMSA) on the corresponding promoter region (-1,282/-907) indicated two regions at (-1,257/-1,158) and (-1,107/-1,008) with the characteristic AGGAGGA-N42-GAGAGGA and its inverted repeat TCCTCTC-N54-TCCTCCT, respectively, appeared to be specific binding sites for cellular factors.

저분자량 수용성 키토산이 분급화된 유전자 전달체의 제조 및 특성 (Preparation and Characterization of Low Molecular Weight Water Soluble Chitosan Gene Carrier Fractioned according to Molecular Weight)

  • 장민자;김동곤;정영일;장미경;나재운
    • 폴리머
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    • 제31권6호
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    • pp.555-561
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    • 2007
  • 다양한 분자량을 가진 저분자량 수용성 키토산을 얻기 위해 젖산염이 결합되어 있는 키토산 올리고당을 한외여과막 장치를 이용하여 분리하였고, 새로운 염 제거법으로 유리 아민기를 가진 LMWSC를 제조하였다. 젖산염이 제거된 LMWSC의 특성과 탈아세틸화도가 적외선 분광기(Infrared spectroscopy, IR) 및 핵자기공명장치($^1H-Nuclear$ Magnetic Resonance, $^1H-NMR$)에 의해 확인되었다. 분자량을 나타내는 다분산지수(PDI)는 $1.278{\sim}1.499$로 비교적 좁은 분자량분포를 나타내었다. 유전자 전달체로서의 가능성을 확인하기 위하여, 성공적으로 분자량에 따라 분리된 키토산 올리고당과 염이 제거된 LMWSC의 유전자 전이효율이 293T cell을 이용하여 확인하였다. 또한 유전자 전이효율을 향상시키기 위해 제조된 LMWSC 유도체가 Balb/C mice를 이용하여 평가되었다.