• Bulletin of the Korean Chemical Society
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• v.14 no.2
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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.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.17 no.2
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• pp.77-83
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• 1981

Four-day bioassay method was used in this study to find out toxicity levels of DDT and PCP. From this study it was found that M. chrysophekadion was the most sensitive to DDT with a 96 h-TL sub(m) value of 0.0044 mg/l followed by P. Sutchi with a 96 h-TL sub(m) value of 0.0056 mg/l, and the most resistant was C. Siamensis with a 96 h-TL sub(m) value of 0.0133 mg/l. In the case of PCP, it was also found that M. Chrysophekadion and P. Sutchi were the first and second most sensitive to PCP with a 96 h-TL sub(m) value of 0.065mg/l PCP and 0.125mg/l PCP respectively, as in the case of DDT study. T. Nilotica was found to be the most resistant to PCP with a 96 h-TL sub(m) value of 0.264mg/l PCP. The resistant power of fish to pollution varies with the species of fish and the types of pollutants. In order of decreasing sensitivity of fish to DDT based on TL sub(m), the following sequence is obtained M. Chrysophekadion, P. Sutchi, T Nilotica, P. Gonionotus, K. Bicirrhis, L. Bicolor, C. Carpio, R. Heteromorpha, C. Siamensis while in the case of PCP, M. Chrysophekadion, P. sutchi, L. Bicolor, K. Bicirrhis, P. Gonionotus (R. Heteromorpha, R. Trilineata), C. Siamensis, C. Carpio, T. Nilotica.

• Progress in Medical Physics
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• v.10 no.1
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• pp.41-46
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• 1999

There is necessity for making a smaller and more sensitive detector in small field sizes. This report assesses the suitability of metal-loaded thermoluminescent dosimeters for this purpose. Measurements were performed in the 6 MV photon and 6 MeV electron beams of a medical linear accelerator with LiF thermoluminescence dosimeters (TLD-100) embedded in solid water phantom. TLD-100 chips(surface area 3.2 $\times$ 3.2 $\textrm{mm}^2$) loaded with a metal plate(Tin or gold respectively) were used to enhance dose readings to TLD-100. Surface dose was measured for field size 10 $\times$ 10 $\textrm{cm}^2$ and 100 em SSD. Measurements have been made of the enhanced signal intensity and good linearity for absorbed dose with each metal. Using a 1 mm each metal on TLD-l00 in the beam increased the surface dose to 14% and 56% respectively for 6MV photon. In the case of 6 MeV electron, gold plate enhanced the TL response to 13%, but there is no difference for tin plate. The specific dose response of TLD-100 with thin metal plate increases with electron concentration of metal film, this is most likely due to increased electron scattered from the additional material with electron density higher than TLD-100. This emphasizes the role of TL dosimeters with metal as amplified dosimeters for therapeutic high energy x-ray beams. Due to the enhanced dose reading of TLD-100 with metal plate, it could be possible to develop smaller TL dosimeter with high sensitivity.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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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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• v.15 no.4
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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.

• Korean Journal of Ichthyology
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• v.8 no.1
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• pp.56-63
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• 1996

Age and growth of spotted halibut, Verasper variegatus were determined using samples collected from commercial catch in the Southern Sea, Korea. Age was determined by counting the otolith annuli which were clearly defined between translucent and opaque zones, and formed between February and March. Growth of spotted halibut was expressed by the von Bertalanffy's equation as $L_t=71.07(1-e^{{\cdot}0.3036(t-0.1173)})$ for females and $L_t=57.44(1-e^{-0.2931(t+0.1590)})$ for males. Almost all the fish examined were younger than 3 years old. The oldest fish was 6 years old in female and 4 years old in male.

• 한국초전도학회:학술대회논문집
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• v.12
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• pp.60-60
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• 2002

• Advances in pediatric surgery
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• v.17 no.2
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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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• v.21 no.9
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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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• v.25 no.9
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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.