• Magazine of the Korea Concrete Institute
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• v.6 no.4
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• pp.85-91
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• 1994

In the previous study, naphthalene and /or naphthol were sulfonated wlth sulfuric acid and they were condensated with formaldehyde. The condensates prepared are subjected to the flow and strength tests of cement rnortnr to examine the chemcal effects of cement adrnlxtures. As the results of flow test, the flow of cement mortar mxed wth naphthol condensates(TSC) and naphthol naphthalene cocondensates( NT5) was larger than those mxed with synthetic naphtha lene condensate (NSS). In the experiments of compressive strength after 28 days curing, the hardned cement mortar containing naphthalene naphthol condensates(N1'5) showed a higher compressive strength than those contairung naphthalene condensates(NSS) and naphthol condensates('I'SC). As a results, the synthetic naphthalene condensates(NT5, TSC 1, whlch used i n this study, are greatly expected as good superplasticizers for the concrete.

• Journal of the Korean Chemical Society
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• v.30 no.2
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• pp.152-158
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• 1986

The dissociation constants of 4-Cl-1-naphthol, 6-Br-2-naphthol and $8-NH_2-2-naphthol$ in aqueous solution were measured by spectroscopic method in the temperature range from 25 to 40${\circ}C$ and pressure up to 2000bar. The dissociation constants were decreased as the substituents were inserted in naphthol f rom $4.4{\times}10^{-10}\;to\;5.82{\times}10^{-11}$ as chloride compound and $2.5{\times}10^{-10}\;to\;3.44{\times}10^{-11}\;or\;4.21{\times}10^{-11}$ as bromine or amino compounds, respectively. This decrease can be explained with the I-or R-effects of substituents. From the dissociation constants various thermodynamic properties were calculated and discussed the characteristics of the dissociation reaction.

• Journal of the Korean Applied Science and Technology
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• v.6 no.2
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• pp.21-28
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• 1989

1-naphthol-2-sulfonic acid and 1-naphthol-4-sulfonic acid were synthesized under the dissolution of 1-naphthol in 2-nitrotoluene with stirring 98.08-90％ sulfuric acid at $5-95^{\circ}C$ for 1-5 hours. As the reaction temperatures and the reaction time were raised, the yield of 2-sulfonate was decreased, while that of 4-sulfonate was increased. But we could not observe the tendency to the various reaction concentrations of sulfuric acids. The mixtures of two isomeric 1-naphtholulfonic acids in excess concentrated sulfuric acids was quantitatively determinded by using multicomponent spectrophotomeric analysis method on the basis of the ultraviolet absorption peak of the sulfonic acids. The standard deviation in this method was ${\pm}\;2.6$, and the above method seem to be rapid and accurate.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.222-223
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• 2015

주석 폐자원에서 전해정련을 통해 고순도 주석을 회수하고자 전해정련에 대한 연구를 수행하였다. 실험결과 전해정련으로는 Pb와 Sn을 분리 회수가 어려우나 전해액의 주석 농도를 25g/L이상으로 유지하고, 황산 첨가를 통하여 전해 주석의 Pb함량 제어가 가능함을 알 수 있었다. 전해를 위한 인가전압은 0.2V에서 고순도의 주석을 얻을 수 있었고, 안정적인 전해정련 공정을 수행하기 위해서는 첨가제로 베타나프톨과 아교가 필요하며 각각 0.1%, 1%가 적정 조건임을 알 수 있었다.

• Journal of Wetlands Research
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• v.16 no.2
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• pp.275-280
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• 2014

Because ammonia in water body can cause water pollution as a result of generating ammonium ion, it is of importance in the management of water quality. This work performed to analyze the ammonium ion by measuring the color band length on the basis of modifying the indophenol method. When 1-naphthol was employed as a coloring agent, the maximum absorbance was shown near 720nm, where the proper injection was in the range of 0.5-1.5ml. About 80% of absorbance was observed after the color development was made within the 20 minutes. In the manufacturing of coloring agent, the proper concentration of NaOH was 1.5-2.5M, and the effect of pH on the color development is negligible. In addition, the color development was effectively in the region of room temperature.

• Analytical Science and Technology
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• v.10 no.4
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• pp.256-263
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• 1997

The new naphthol-containing hexadentate ligands, 1,12-bis (2-naphthol)- 2,5,8,11-tetraazadodecane 4HCl (nptr) and 1,14-bis(2-naphthol)- 2,6,9,13- tetraazatetradodecane .4HCl (npptr) were synthesized and characterized by elemental analysis, IR, NMR, and mass spectrometry. Acid dissociation constants and stability constants of Co(II), Ni(II). Cu(II), and Zn(II) complexes were determined at $25.0^{\circ}C$ and ionic strength ($\mu$)=0.10M($KNO_3$) by potentiometry. The relationship between basicity and stability constants of ligands containing aliphatic amines and 2-naphthol were studied.

• Journal of the Korean Chemical Society
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• v.38 no.5
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• pp.351-358
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• 1994

The spectrophotometric determination of trace selenium(Ⅳ) using its catalytic reaction has been studied in aqueous solutions. The catalytic reaction of phenylhydrazine hydrochloride with selenium(Ⅳ) in an acidic aqueous medium produces benzenediazonium ion which will be converted into a red-coloured azo dye by coupling with H-acid(8-amino-1-naphtol-3,6-disulfonic acid disodium salt). For the reaction, the experimental conditions such as amounts of the reagents and pH of the sample solutions were optimized. After 15 ml of the sample solution was treated with 1 ml of 0.1 M EDTA solution to mask $Fe^{3+}$, etc., 1 ml of 0.06 M phenylhydrazine hydrochloride, 1 ml of 0.02 M H-acid, and 3 ml of 0.3 M-$KClO_3$ were added into the solution, sequentially. The solution was adjusted to pH 1.4 with HCl. After it was heated in a steam bath for 30 minutes, the solution was cooled down to a room temperature and then diluted to 25 ml with deionized distilled water. A blank solution for the absorbance measurement was prepared from the deionized water. The absorbance was measured at 527 nm. Using the above procedure, the trace amount of selenium was determined in natural waters such as tap, river and pond waters by a standard curve method and recoveries of Se spiked to samples were also obtained. From the recoveries of 104 to 111%, it could be concluded that this method was applicable to the quantitative determination of ng/ml level of selenium in natural waters.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.279-285
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• 2008

The etherification of 2-naphthol with ethanol has been carried out over various solid acid catalysts. CNS, CNSWS, SCMS, MCF, and SBA-15 with and without sulfonic acid were used in this study as solid acid catalysts. The conversion of 2-naphthol and the selectivity of 2-naphthyl ethyl ether were obtained at reaction temperature = $180^{\circ}C$, $LHSV=1h^{-1}$, ethanol/2-naphthol molar ratio = 20 using a fixed-bed down flow reactor. The conversion of 2-naphthol and the selectivity of 2-naphthyl ethyl ether over silica group catalysts were higher than them over carbon group catalysts. The conversion of 2-naphthol was 70-90% and the selectivity of 2-naphthyl ethyl ether was more than 90% over silica group solid acid catalysts. It was performed XRD, SEM, TEM, and $NH_3-TPD$ to characterize solid acid catalysts.

• Journal of Life Science
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• v.30 no.1
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• pp.96-105
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• 2020

Sirtuin inhibitors are pharmaceutically and therapeutically valuable compounds that inhibit sirtuin, a type III histone deacetylase. Synthetic sirtuin inhibitors were discovered and characterized using cell-based screens in yeast (Saccharomyces cerevisiae) and have been used in the study of aging, carcinogenesis, and diabetes, all of which are related to sirtuin function. For medical applications, synthetic inhibitors have been further developed for increased potency and specificity, including compounds containing nicotinamide, thioacetyl lysine, β-naphthol, and indole derivatives. Suramin, tenovin, and their analogues were developed as a result. Sirtuin inhibitors were found to affect organic development and have been used to genetically modify plants, although a sirtinol-resistant mutation in the biosynthesis of a molybdopterin cofactor for an aldehyde oxidase has been identified. Some natural flavonoids, and catechin and quercetin derivatives also act as sirtuin inhibitors have been studied to identify a more potent inhibitor for therapeutic purposes. In this review, sirtuin is introduced and the therapeutic inhibitors that have been developed are presented, particularly sirtinol which has been used for genetic modification in plants though it was not designed to be so. Sirtuin inhibitors with greater potency and selectivity are required and those developed in pharmaceutics should be used in plant research to identify more authentic sirtuins in plants.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.4
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• pp.247-256
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• 2013

In this study, alginate beads containing birnessite (Bir-AB), a highly reactive oxidative catalyst for the transformation of phenolic compounds, was prepared and its 1-naphthol (1-NP) removal efficiency was investigated in a batch test. Based on scanning electron microscopy image, it can be inferred that the alginate gel cluster acts as a bridge which bind the birnessite particles together. Kinetic experiment with Bir-AB of different mixing ratios of birnessite to alginate (Bir : AG=0.25 : 1~1 : 1 w/w) indicate that pseudo-first order kinetic constants, $k(hr^{-1})$ for the 1-NP removals increased about 1.5 times when the birnessite mixing ratio was doubled. The removals of 1-NP was found to be dependent on solution pH and the pesudo-first order rate constants were increased from 0.331 $hr^{-1}$ at pH 10 to 0.661 $hr^{-1}$ at pH 4. The analysis of total organic carbon for the reaction solutions showed that a higher removal of dissolved organic carbon was achieved with Bir-AB as compared to birnessite. HPLC chromatographic analysis of the methanol extract after reaction of 1-NP with Bir-AB suggest that the reaction products could be removed through incorporation into the aliginate beads as a bound residue. Mn ions produced from the oxidative transformation of 1-NP by birnessite were also removed by sorption to Bir-AB. The Bir-AB was recovered quantitatively by simple filtration and was reused twice without significant loss of the initial reactivity.