• Bulletin of the Korean Chemical Society
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• 제14권2호
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• pp.191-195
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• 1993

Molecular orbital calculations at the extended Huckel level have been carried out for an electron deficient cluster, $Tl_3(FeL_3)_2{(FeL_4)_3}^{-3}$, where L=CO or $H^-$. The LUMO, $2a_2$", is destabilized by the secondary interaction of the LUMO with $1a_2$" on $(FeL_3)_2$ fragment. This is one of six skeletal bonding orbitals which are associated with $Tl-FeL_3$ bonds. Overlap population analysis has been applied to account for two kinds of Tl-Fe bonds. Replacement of the terminal $C_{3v}$, $FeL_4$, by the $C_{2v}$, $FeL_4$ units in cluster results in slight energy stabilization of the cluster.

• 수산해양기술연구
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• 제17권2호
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• pp.77-83
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• 1981

하천 오염에서 문제시되고 있는 유기오염 물질인 PCP 와 DDT의 환경기준을 평가하고 담수어 어종간의 독성에 대한 저항성을 연구하였다. 각 어종에 대하여 24, 48, 72 및 96시간의 TL sub(m) 값을 산출하였던 바 오염물질에 대한 저항성은 오염물질의 성상에 따라 상이한 양상을 보여주었다. 실험한 10종의 담수어중 PCP 및 DDT에 저항성이 약한 어종은 N. Chrysophekadion으로 96 h-TL 하(m) 값은 0.065mg/l 과 0.0044mg/l으로 각각 나타났으며 PCP에 저항성이 강한 어종은 T. nilotica로서 96 h-TL 하(m) 값은 0.264mg/l이었으나, DDT에 대해서는 C. Siamensis로서 96 h-TL 하(m) 값은 0.0133mg/l로 평가되었다.

• 한국의학물리학회지:의학물리
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• 제10권1호
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• pp.41-46
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• 1999

본 실험은 의료용 가속기로부터 나오는 6MV 광자선과 6 MeV 전자선을 고체 팬텀위의 LiF 열형광 선량계 (TLD-l00)에 쪼여서 수행하였다. TLD-l00의 방사선 반응감도를 증가시키기 위해 TLD-l00 기판 (표면적 3.2 $\times$ 3.2 $\textrm{mm}^2$) 위에 같은 면적의 금속박막 (주석 혹은 금)을 얹어서 실험하였다. SSD l00cm, 방사선장의 크기 10$\times$10 $\textrm{cm}^2$의 조건 하에서 표면 흡수선량을 측정하였다. 측정결과 각 금속들로 인하여 TLD-l00 의 신호강도가 증강된 것이 관측되었다. 그리고 표면 흡수선량이 방사선량에 따라서 매우 선형적인 값을 가지는 것으로 나타났다 .6 MV 광자선의 경우 1 mm 의 금속박막을 TLD-l00 에 얹은 결과 표면 흡수선량이 각 각 14%, 56% 증가되었다 .6MeV의 전자선의 경우에는 금박막은 TL 반응감도가 13% 증가되었으나 주석의 경우에는 전혀 변화가 없었다. 금속박막을 얹은 TLD-l00의 방사선량 반응감도는 금속박막의 전자 입자밀도에 따라 증가하는 것으로 관측되었다. 이것은 TLD-l00보다 큰 전자밀도를 가진 부가물질(금속박막 )로부터 TLD-l00으로 산란전자가 유입되는 데 기인하는 것으로 보인다. 이 결과로부터 금속박막을 얹은 TL 선량계가 치료광자선용 증폭 선량계로서의 역할을 할 수 있을 것임을 시사한다. 즉 금속박막으로 인해서 TLD-l00 의 방사선 량 반응감도가 증가되었으므로 높은 감도의 보다 작은 TL 선량계의 개발이 가능하게 되었다.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2001년도 추계학술발표대회 논문집 제20권 2호
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• pp.379-382
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• 2001

In the muffler industry, the main purpose of the research works is to determine a way to increase the TL (Transmission Loss) properties of the muffler, without deteriorating the back pressure influence. In order to obtain better results, several works have been done by changing the geometrical characteristics of the muffler or the type of the muffler. This work will focus on the perforated muffler components with concentric chamber, to investigate the effect of a non-uniform porosity along the inner perforated tube of the muffler on the TL. It is noted that varying the perforation ratio affects the peaks frequencies of the TL, especially fer $2\pi < kL < 4\pi$ (in the case of L : 200mm for the concentric resonator). The magnitudes of the TL, for this range of frequencies, vary noticeably by changing the porosity distribution.

• Fisheries and Aquatic Sciences
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• 제15권4호
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• pp.353-359
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• 2012

Age and growth of Hemibarbus labeo caught from Goe-san Lake in South Korea from March to November, 2011, were studied. A total of 201 specimens was collected, ranging from 110 to 580 mm in total length (TL). Males and females made up 47.9% and 52.1% of the sample, respectively. Marginal increment analyses showed that vertebral increments, each composed of one opaque and one hyaline zone, were deposited annually. Opaque edges were prevalent from June to July. The relationship between TL and vertebral radius was linear, with equations of R = 0.008TL - 0.208 (male) and R = 0.009TL - 0.272 (female). Regression equations between TL and total weight (TW) were $TW=9{\times}10^{-6}TL^{2.987}$ (male), $TW=8{\times}10^{-6}TL^{3.014}$ (female), and $TW=9{\times}10^{-6}TL^{2.988}$ (combined sexes), according to the von Bertalanffy growth equation. Back-calculated TL was expressed using the von Bertalanffy equation as follows: $L_t=438.25(1-e^{-0.175(t+0.164)})$ for males, $L_t=483.36(1-e^{-0.147(t+0.115)})$ for females, and $L_t=464.86(1-e^{-0.162(t+0.176)})$ for the sexes combined. The growth performances were 4.526, 4.536, and 4.544, respectively.

• 한국어류학회지
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• 제8권1호
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• pp.56-63
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• 1996

1992년 12월부터 1993년 12월까지 매월 1회씩 남해안에서 어획된 범가자미를 대상으로 연령과 성장을 조사하였다. 연령사정은 이식으로 하였으며, 윤문은 투명대에서 불투명대로 이행하는 경계로 하였다. 윤문은 2월부터 3월 사이에 연 1회 형성되었다. 이석경(R)에 대한 전장(TL)의 관계를 보면 암컷은 TL=18.0329R-11.6879, 수컷은 TL=15.1458R-5.6902였다. 전장(TL)에 대한 체중(BW)의 관계는 암컷은 $BW=0.0065TL^{3.2042}$, 수컷은 $BW=0.0146TL^{2.9620}$이었다. 연령(t)에 대한 체장(Lt)의 Von Bertalanffy 성장식은 암컷은$L_t=71.0783(1-e^{-0.3036(t-0.1173)})$, 수컷은 $L_t=57.4414(1-e^{-0.2931(t+0.1590)})$이었다. 채집된 표본 중 암컷은 6세, 수컷은 4세까지 있었지만 대부분 3세 이하였다.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2002년도 High Temperature Superconductivity Vol.XII
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• pp.60-60
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• 2002

• Advances in pediatric surgery
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• 제17권2호
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• pp.179-187
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• 2011

Experimental tracheal ligation (TL) has been shown to reverse the pulmonary hypoplasia associated with congenital diaphragmatic hernia (CDH) and to normalize gas exchange. The purpose of this study was to determine whether the TL would correct the surfactant deficiency present in the fetal rabbit model of CDH by using lamellar body count. Lamellar bodies are synthesized and secreted by the type II pneumocytes of fetal lung. The phospholipids present in these bodies constitute the major component of pulmonary surfactant. Twenty-one pregnant New Zealand rabbits underwent hysterotomy and fetal surgery on gestational day 24. Two fetuses of each pregnant rabbit were operated. In the fetus of one end of bicornuate uterus, left DH was created by excision of fetal diaphragm through open thoracotomy (DH Group). In the fetus of the other end of bicornuate uterus, left DH and TL were created (TL Group). The fetuses were delivered by Cesarean section on gestational day 31. Fourteen in control group, 12 in the DH group and 13 in TL group were born alive. En bloc excision of lungs, bronchi and trachea was done in all newborn rabbits. A five Fr catheter was inserted through trachea and repeated irrigations with 10 cc normal saline were done. The irrigated fluid was centrifuged at $280{\times}g$ for 5 minutes and the lamellar bodies were counted with the upper level fluid in platelet channel of electronic cell counter. The average lamellar body counts were $37.1{\pm}14.2{\times}10^3/{\mu}L$ in control group, $11.5{\pm}4.4 {\times}10^3/{\mu}L$ in DH group, and $6.5{\pm}0.9{\times}10^3/{\mu}L$ in TL group. Lamellar body count in DH group was lower than in control group and did not increase after TL. This study shows TL has no therapeutic effect on decreased surfactant level of CDH and the pregnant rabbit is appropriate for the animal model of CDH.

• Bulletin of the Korean Chemical Society
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• 제21권9호
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• pp.909-912
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• 2000

Thallium(I) selective electrodes based on meso-alkyl substituted calix[4]pyrroles such as, meso-octamethyl-calix[4]pyrrole (L1), meso-octaethylcalix[4]pyrrole (L2) and meso-tetraspirocyclohexylcalix[4]pyrrole (L3) as sensor molecules have been pre pared and tested. The conditioned electrode (E4) incorporating L3gave best results with a wide working concentration range of 10-5.5 ~10-1 M near-Nernstian slope of 56.0 mV/decade of activity and detection limit of 10-6.0 M. This electrode exhibited a fast response time of 30 s and high selectivity over Na+ , K+ and other metal ions with only Ag+ interfering. The electrode works well in the pH range 2.0-11.0 and can be successfully employed for the determination of Tl+.This proposed electrode was also used as an indicator electrode in potentiometric titration of Tl+.

• Bulletin of the Korean Chemical Society
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• 제25권9호
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• pp.1309-1313
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• 2004

A simple and reliable method has been developed to selectively separate and concentrate trace amounts of thallium ion from real samples for the subsequent measurement by flame atomic absorption spectrometry (FAAS). Thallium ions are absorbed quantitatively during passage of aqueous real samples through an octadecyl bonded silica membrane disk modified by 4-(4-Chloro-phenylazo)-2-[(4-hydroxy-phenylamino)-methyl]-phenol. The retained $Tl^+$ ions are then stripped from the disk quantitatively with a minimal amount of thiosulfate solution as eluent. The proposed method permitted large enrichment factors of about 130 and higher. The relative standard deviation for ten replicate extraction of thallium from 1 L samples containing 5 ${\mu}g$ thallium is 1.2%. The break through volume for 5 ${\mu}g$ thallium is 1000 mL. The limit of detection of the proposed method is 11.2 ng of $Tl^+$ per 1000 mL. The effects of various cationic interferences on the recovery of thallium in binary mixtures were studied. The method was applied to the recovery of $Tl^+$ ions from natural water and human hair samples.