• Journal of Veterinary Science
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• v.22 no.6
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• pp.78.1-78.10
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• 2021

Background: Recurrent subclinical mastitis (RScM) due to resistant bacteria has low clinical and bacteriological cure rates, often requiring the culling of cows. The sequential intramammary administration of enrofloxacin hydrochloride-dihydrate (enro-C) followed by ceftiofur HCl may be useful for treating these cases. Objectives: This study assessed the bacteriological and clinical cure-efficacies of the sequentially intramammary administration of enro-C, followed by ceftiofur HCl to treat RScM in Holstein/Friesian cows. Methods: This trial was conducted in a herd with a high prevalence of RScM, and 20 Holstein/Friesian cows were included: 45% suffering subclinical mastitis and 38.9% of the mammary quarters affected. Twenty-nine bacterial isolates in vitro resistant to enro-C were obtained (coagulase-negative Staphylococcus spp, 55.2%; Staphylococcus aureus, 27.6%; Escherichia coli, 6.9%; Streptococcus uberis, 6.9%; Corynebacterium bovis, 3.4%). Polymerase chain reaction-isolated the following genes linked to enro-C resistance: chromosomal (gyrA) and plasmid (aac(6')-lb-cr). The treatments were as follows: twice-daily intramammary infusions of enro-C (300 mg/10 mL) for 5 days. Cows clinically considered treatment failures were also treated with intramammary ceftiofur (125 mg/10 mL, twice daily for 5 days. The clinical and bacteriological cure rates were carried out when completing each treatment phase and at 14 and 21 days, aided by a California mastitis test, somatic cell count, and failure to identify the initially causative bacteria. Results: Enro-C achieved 65% clinical and bacteriological cure rates, and 100% cure rates were obtained after the rescue treatment with ceftiofur HCl. Conclusions: Outstanding clinical and bacteriological cure rates in cows affected by RScM were achieved with the consecutive intramammary infusions of enro-C, followed by ceftiofur HCl.

• Korean Journal of Pharmacognosy
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• v.33 no.3 s.130
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• pp.252-256
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• 2002

In the previous study, we demonstrated that ginsenoside $Rb_1$ isolated from the butanol fraction of the head of Panax ginseng had significant gastroprotective activity on gastritis and gastric ulcer models in rats. It has been well established that drugs to have capacity of scavenging or inhibiting the generation of reactive oxygen radicals prevent the gastric mucosal injury. Ginsenoside $Rb_1$ was tested on HCl ethanol-induced gastritis in rats, DPPH-induced free radical scavenging effect, MDA assay, GSH activity, and SOD activity in gastric tissue. It showed significant inhibition in HCl ethanol-induced gastritis, and al~o significantly increase of GSH activated SOD. We speculate that the protective effect of ginsenoside $Rb_1$ against HCl ethanol-induced gastric mucosal damage is originated from the increase of GSH and the activation of SOD.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.8
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• pp.657-662
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• 2003

This paper presents a new fabrication method of selective SiGe epitaxial growth at 650 $^{\circ}C$ on (100) silicon wafer with oxide patterns by reduced pressure chemical vapor deposition. The new method is characterized by a cyclic process, which is composed of two parts: initially, selective SiGe epitaxy layer is grown on exposed bare silicon during a short incubation time by SiH$_4$/GeH$_4$/HCl/H$_2$system and followed etching step is achieved to remove the SiGe nuclei on oxide by HCl/H$_2$system without source gas flow. As a result, we noted that the addition of HCl serves not only to reduce the growth rate on bare Si, but also to suppress the nucleation on SiO$_2$. In addition, we confirmed that the incubation period is regenerated after etching step, so it is possible to grow thick SiGe epitaxial layer sustaining the selectivity. The effect of the addition of HCl and dopants incorporation was investigated.

• Resources Recycling
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• v.22 no.6
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• pp.26-32
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• 2013

In order to recover Pt from the hydrochloric acid leaching solution of spent catalysts, bench scale Karr reciprocating column was employed. At an optimum flow rate and vibration frequency, iron and Pt was completely extracted by using TBP and Aliquat 336. At the same vibration frequency, iron and Pt was completely stripped by HCl and $HClO_4$ after adjusting the flow rate. In the case of extraction of HCl from the raffinate with TEHA, it was difficult to maintain the stability of the column extractor. A comparison of the operation results between column extractor and mixer-settler is reported.

• Journal of the Korean Applied Science and Technology
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• v.29 no.2
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• pp.268-277
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• 2012

The thermal decomposition characteristic of waste PVC wires has been studied by using TGA and fixed-bed reactor. The experimental conditions of decomposition temperatures, air flow rates and weight ratio of CaO/PVC were considered in this work. To verify the effectiveness of CaO addition to remove HCl and toxic gases generated from thermal decomposition of PVC wire, the gaseous products obtained from the thermal decomposition of PVC were analyzed by GC/MS(Gas Chromatograph and Mass Spectrometry). To investigate the effect of CaO in thermal decomposition of PVC, liquid products were also analyzed by GC/MS. And the effect of decomposition temperature, air flow rate and CaO/ PVC weight ratio on the yield of liquid, gas and residue fraction have been also studied. From this work, it was found that the removal amount of HCl generated from thermal decomposition of PVC increased with increase of CaO addition.

• Journal of the Korean Chemical Society
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• v.33 no.1
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• pp.11-17
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• 1989

Pyrazinium chlorochromate and dipyrazinium trichromate which are pyrazinium salts were prepared by the each reaction of pyrazine with chromium trioxide under the presence of HCl and $CH_2Cl_2$. These compounds wese nonhygroscopic and were solved in water very well. Physical properties such as solubility, pH, electrical conductivity, and melting point were measured. These compounds were considered to be ionic ; $C_4H_4N_2H^+$, $CrO_3Cl^-$, $Cr_3O^{2-}_{10}$ by the measurement of electrical conductivity. It was found that CrO$_3$ was formed in the first decomposition process of salts and it was changed into $Cr_2O_3$ in the second process as its weight is decreased. It was also found that especially under the same condition dipyrazinium salt was in the form of isopoly ($Cr_2O^{2-}_{10}$)anion which has been thought to be in the form of $Cr_2O^{2-}_{7}$ obtained from pyridine.

• Journal of the Korean Chemical Society
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• v.59 no.3
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• pp.238-245
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• 2015

The crystallization and morphology change of amorphous titanias by hydrothermal treatment have been investigated. The amorphous titanias were prepared by pure water hydrolysis of two different precursors, titanium tetraisopropoxide (TTIP) and TTIP modified with acetic acid (HOAc) and characterized prior to hydrothermal treatment. In order to avoid complicate situation, the hydrothermal treatment was performed in a single solvent water with and without strong acids at various temperatures. The effects of strong acid, temperature and time were systematically investigated on the transformation of amorphous titania to crystalline TiO₂ under simple hydrothermal condition. Without strong acid the titanias were transformed into only anatase phase nanoparticle regardless of precursor type, temperature and time herein used (up to 250 ℃ and 48 hours). The treatment temperature and time effected only on the crystalline size, not on the crystal phase et al. However, it was clearly revealed that the strong acids such as HNO₃ and HCl catalyzed the formation of rutile phase depending on temperature. HCl was slightly better than HNO₃ in this catalytic activity. The morphology of rutile TiO₂ formed was also a little affected by the type of acid. The precursor modifier, HOAc slightly reduced the catalytic activity of the strong acids in rutile phase formation.

• Journal of the Korean Chemical Society
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• v.24 no.6
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• pp.463-468
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• 1980

Tris(hydroxyethyl) phosphate, ethylphosphoramidic dichloride, N,N-diethylphosphoramidic dichloride, bis(hydroxyethyl) N-ethylphosphoramidate and bis(hydroxyethyl) N,N-diethylphosphoramidate were synthesized and characterized. Phosphate and phosphoramidates were polymerized with the elimination of ethylene glycol when heated under reduced pressure and they gave no molecular ion peaks in their mass spectra. And also ethylphosphoramidic dichloride gave polymeric products at 180$^{\circ}C$ with the evolution of HCl. IR spectra showed characteristic P=O streching bands in the range of 1,300 to$ 1,200 cm^{-1}.$

• Bulletin of the Korean Chemical Society
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• v.26 no.12
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• pp.1953-1961
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• 2005

We have performed high-level quantum mechanical calculation for multiple proton transfer in HOCl + HCl and $H_2O$ + $ClONO_2$ on water clusters, which can be used as a model of the reactions on ice surface in stratospheric clouds. Multiple proton transfer on ice surface plays crucial role in these reactions. The structures of the clusters with 0-3 water molecules and the transition state structures for the multiple proton transfer have been calculated. The energies and barrier heights of the proton transfer were calculated at various levels of theory including multi-coefficient correlated quantum mechanical methods (MCCM) that have recently been developed. The transition state structures and the predicted reaction mechanism depend very much on the level of theory. In particular, the HF level can not correctly predict the TS structure and barrier heights, so the electron correlation should be considered appropriately.

• Natural Product Sciences
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• v.7 no.3
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• pp.90-93
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• 2001

The effects of the dried fruit powder of Opuntia ficus-indica var. saboten (OF-f) were investigated on gastric lesion and ulcer models in rats. It showed significant inhibition in HCl ethanol and HCl aspirin induced gastric lesion at a dose of 600 mg/kg, p.o. OF-f also showed significant inhibition in indomethacin induced gastric lesion at the doses of 200 and 600 mg/kg, p.o. However, it did not affect aspirin and Shay ulcer in rats. It also did not affect the gastric juice secretion, acid output and pH. These data suggest that OF-f possesses pronounced inhibitory action on gastric lesion of rats.