• Journal of the Korean Chemical Society
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• v.42 no.1
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• pp.84-91
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• 1998

Random copolymers of N-isopropyl acrylamide (NIPAAm) and acrylic acid (AAc) which exhibit temperature- and pH-responsive behavior were synthesized by free-radical polymerization. The copolymers were characterized by means of FT-IR spectrometry and titration. The influence of polyelectrolyte on the lower critical solution temperature (LCST) of pH/temperature-sensitive polymers was investigated in the pH range of 2-12. The LCSTs of PNIPAAm/water in poly(NIPAAm-co-AAc) were determined by cloud-point measurements. A polyelectrolyte complex was prepared by mixing poly(NIPAAm-co-AAc) with poly(allylamine) (PAA) or poly(L-lysine) (PLL) solutions as anionic and cationic polyelectrolytes, respectively. Back titration was performed to determine the content of AAc and to study the effect of comonomer ionization on the LCST. The LCSTs of PNIPAAm/water in the copolymers were strongly affected by pH, presence of polyelectrolyte, AAc content, and charge density on the polymer. The polyelectrolyte complexes were formed at neutral condition. The influence of more hydrophobic PLL as polyelectrolyte on the cloud-point of PNIPAAm/water in the copolymer was stronger than that of poly(allylamine) (PAA).

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.6
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• pp.550-561
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• 2009

This study is to investigate the air pollution characteristics of an industrialized midsize west-coastal city by comparing air quality to a neighboring inland city. The hourly averaged data of $O_3$, $SO_2$, $NO_2$, CO, and $PM_{10}$ measured from continuous air quality monitoring sites in Gunsan (coastal) and Jeonju (inland) were analyzed. The data set covers the period from 2004 to 2006. The annual average concentrations of the air pollutants in two cities were compared in their abundances and temporal trends as well. $O_3$ and $SO_2$ in Gunsan were relatively higher than those in Jeonju, while vice versa in case of $NO_2$ and $PM_{10}$. It seems that heavy automobile emissions from Jeonju mainly bring on higher $NO_2$ and $PM_{10}$ than those in Gunsan on annual base. $NO_2$ concentrations in both cities showed bimodal diurnal variations with peaks in the morning and in the late evening. These peaks correspond to the coupled effects of rush hour traffic and meteorological conditions (i.e., variation of mixing height and dispersion conditions). Maximum hourly averages of $NO_2$ ranged from 18 ppb to 28 ppb at Jeonju, and from 12 ppb to 20 ppb at Gunsan. $O_3$ showed typical diurnal variation with a maximum in the afternoon between 14:00 and 16:00 LST. Diurnal variations of CO and $PM_{10}$ were similar to $NO_2$ while $SO_2$ was similar to $O_3$. Seasonal variations of $PM_{10}$ in both cities indicated that their concentrations during spring season were significantly high. Asian dust storms occur frequently during spring and seem to affect increase in $PM_{10}$. High $O_3$ and $PM_{10}$ days were selected from both cities. The analyses based on the HYSPLIT trajectory model during the high $O_3$ and $PM_{10}$ showed these episodes (six cases) were mostly coincident with Asian dust storm originated from northern China and Mongolia. However, these high air pollution episodes in the west coastal cities may not only be caused by the Asian dust but also affected by other air pollutants transported from China accompanying the Asian dust.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.4
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• pp.47-54
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• 2010

This study is progressed function ratio, it's trued taste by an experiment to present data for human work light weight aggregate development that use clink ash progressed liquid limit, small success limit, wear loss in quantity, sand equivalent, sieve cutting examination. 80:20's match of function rain examination is 1.4, and that use rubble aggregate as recyeled-panit lightweight aggregate's capacity ratio increases by 1.0 increase of function rain many. Also, examination multiplied delicate flavor gradually according to increase of the mixing rate, and absorption coefficient increased. This is judged by phenomenon that appear by special quality upper recycled-panit of polystyrene bid and porosity's increase between lightweight aggregate. It is case that use aggregate of wear loss in quantity is 13.5 in sand equivalent and a wear loss in quantity experiment and although case that mix 20% increases by 14.4, this phenomenon by weak tissue of lightweight aggergate be judged. When it's as a these experiment, the statue prevention floor of a street improvement specifications is prescribing so that satisfy by sand equivalent 20, CBR 10. This is showed result that this satisfies in quality standard all in match experiment ago that see.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.6
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• pp.571-580
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• 1985

Based on the data collected by R/V "Shinkai Maru" of the Japan Marine Fishery Resources Research Center during the period from April 1978 to April 1979, seasonal migration of Merluccius hubbsi was studied using the catch per fishing effort (tons/30 min. haul) and gonad maturity index (gonad weight /body weight X $10^3$). Merlurccius hubbsi are found in the area between $36^{\circ}S\;and\;54^{\circ}S$ along the coast of Arzentine and are abundant especially above the 100 fathoms in northern offshore of $48^{\circ}S$. It was observed that critical maturity body lengths (spawning minimum body length) in terms of gonad maturity index are 40 cm and 30cm in female and male respectively, while spawning seasons are from December to January and from November to December for female and male respectively. It was assumed that while the group which distrbutes in the north ($36^{\circ}S{\sim}39^{\circ}S$) in spring moves down south to $42^{\circ}{\sim}46^{\circ}S$ for spawning in summer (from December to January), the group which does not move or a part of this group which comes back to the north spawn in the area north of $42^{\circ}S$ throughout the long period except winter time (from July to August). Southern group as well might move north and spawn after mixing together with northern group at $42^{\circ}{\sim}46^{\circ}S$ area around the period of December to January,

• Polymer(Korea)
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• v.36 no.4
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• pp.542-548
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• 2012

Morphological characteristics and formation of symmetric polystyrene-block-poly(1,4-butadiene) copolymer (PS-b-PBD) in thin films upon solvent-annealing were investigated by using atomic force microscopy (AFM). The thin films solvent-annealed in cyclohexane revealed the perforated lamellae of poly(1,4-butadiene) in the matrix of polystyrene while those solvent-annealed in n-hexane exhibited highly disordered patterns. Interestingly, when the thin films of PS-b-PBD were solvent-annealed with binary mixtures of cyclohexane and n-hexane, the morphological transition from the perforated lameallae to the perpendicularly-oriented lamellae of poly(1,4-butadiene) could be induced by changing the mixing ratio of both solvents. We also demonstrated that after microdomians of poly(1,4-butadiene) were successfully degraded by UV-$O_3$, linear poly(dimethyl siloxane) chains were back-filled into the etched regions of the thin film and then converted to silica nano-objects by oxygen plasma treatments.

• Journal of the Korean Institute of Oriental Medical Informatics
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• v.17 no.2
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• pp.82-129
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• 2011

"Beijijiufa" is a medical book republished by Sun Ju Qing in 1245. He compiled this book having added "Qizhumajiufa" and "Zhugejingyanbeijiyaofang" to the contents of "Beijijiufa" authored by Wen Ren Qi Nian. In "Beijijiufa" the author described treatment methods making use of moxibustion methods in connection with 22 cases of acute diseases. The author had collected the moxibustion methods used to treat acute diseases, which had been practiced by the medical practitioners of many generations, and quoted total 13 medical men's practices. In the book, the greatest parts of details were quoted especially from the writings of Sun Si Miao and Ge Hong, and this shows that the medical philosophies of both Sun Si Miao and Ge Hong were reflected onto "Beijijiufa". He had differed on his moxibustion practice: the size of moxa wool, the number of moxibustion treatment, and method of moxibustion for male and female were differed from one another according to the disease. As to the area of moxibustion, he chose the body parts around under four limbs and joints, and mostly used extraordinary acupoints rather than twelve main meridians. In his descriptions of finding meridian points, he did not describe it by its specific name of the reaction point, but explained the location of moxibustion points in detail through pictures. "Qizhumajiufa" is related to moxibustion method and prescriptions to treat surgical diseases, like skin boils or furuncle on the back, etc. He easily explained the method to find the meridian points for moxibustion treatment by using particular way through diagrams and pictures. Eight prescriptions he used were the collections among the historical practices of medical practitioners of many generations for skin boils which showed excellent therapeutic actions. In "Zhugejingyanbeijiyaofang", there are prescribed for 36 disease, also is the records of treatment methods for medical emergency which would be encountered easily in everyday life. As to therapeutic remedies, varied treatment methods, including the treatment by means of pasting and attaching medicinal substance to the spot, the treatment by means of mixing medicinal substance with alcoholic beverage, cleansing method, smoke inhalation remedy etc. were introduced. In "Beijijiufa" moxibustion was regarded as a top priority for treatment of acute disease, and the author strived to present remedies to the readers as easily as possible through 19 pictures. Regarding prescriptions, the author introduced diverse treatment methods with respect to various disease symptoms, and described the method to treat disease symptoms making use of medicinal ingredients which can easily be found in daily life. Likewise, "Beijijiufa" compiled by Sun Ju Qing was intended for clinical practice, and was indeed a medical book having been utilized for treatment of acute diseases in those days.

• Journal of the Korean Society of Radiology
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• v.12 no.6
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• pp.777-783
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• 2018

The purpose of this study was to investigate the degree of tearing of the rubber when the spike of the syringe connector was connected to the bottle of the contrast medium composed of the rubber compound type and to investigate the presence of the synthetic rubber due to tearing and grinding and the size of the pulverized product when the pulverized matters rubber was detected. As a result, in the case of tearing degree, the front side of the first contact with the end of the syringe connector was torn more than the back side by about $3.14{\pm}0.04mm$, and the pulverized matters was detected on average 7 to 15 on the 10 contrast mediums. The average particle size was measured to be about $7.89{\pm}0.31{\mu}m$. In addition, it is necessary to develop a micro_filter type automatic injection system for blocking off the pulverized matters as well as additional experiments through various experiments and analysis methods, and it is considered that interest of related organizations will be needed in preparation of fatal accidents when pulverized matters is introduced.

• Economic and Environmental Geology
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• v.52 no.3
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• pp.213-221
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• 2019

The Wugang banded iron formation (BIF) is located within the Taihua complex at the southern margin of the North China Craton (NCC). In this study, we analyzed major elements and rare-earth elements in iron ores from the Wugang BIF, to study the type of BIFs and their formation mechanism in combination with previously-published data from the literature. We found that the iron ores from the Wugang BIF display two types of banding textures, which can be described as weak banding or no banding. The samples are composed of coarse-grained magnetite, quartz, pyroxene, and amphibole. Based on our geochemical results, mixing of a hydrothermal fluid with sea water led to the precipitation of the Wugang BIF, and there is evidence of crustal contamination. These results, combined with previous literature data, almost all of the iron ores lack Ce anomalies, though some samples show negative Ce anomalies. Our results indicate that the Wugang BIF was formed in a dominantly reducing environment, although the surfaces were relatively oxidized. Geochemical evidence suggests that the Wugang BIF iron ores were formed in a near-shore continental-shelf environment or in a back-arc basin. The BIF is known as interbedded with migmatite, amphibole gneiss, minor quartz and marble, which indicating lack of volcanic materials input. This study, combined with previous results on geochemical interpretation of related wall rock of Wugang BIF, demonstrated that Wugang BIF belongs to Superior-type BIF.

• Geomechanics and Engineering
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• v.35 no.1
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• pp.29-39
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• 2023

As the intensity of urban underground space development increases, more and more tunnels are planned and constructed, and sometimes it is inevitable to encounter situations where tunnels have to underpass the river embankments. Most previous studies involved tunnels passing river embankments perpendicularly or with large intersection angle. In this study, a project case where two EPB shield tunnels with 8.82 m diameter run parallelly underneath a river embankment was reported. The parallel length is 380 m and tunnel were mainly buried in the moderate / slightly weathered clastic rock layer. The field monitoring result was presented and discussed. Three-dimensional back-analysis were then carried out to gain a better understanding the interaction mechanisms between shield tunnel and embankment and further to predict the ultimate settlement of embankment due to twin-tunnel excavation. Parametrical studies considering effect of tunnel face pressure, tail grouting pressure and volume loss were also conducted. The measured embankment settlement after the single tunnel excavation was 4.53 mm ~ 7.43 mm. Neither new crack on the pavement or cavity under the roadbed was observed. It is found that the more degree of weathering of the rock around the tunnel, the greater the embankment settlement and wider the settlement trough. Besides, the latter tunnel excavation might cause larger deformation than the former tunnel excavation if the mobilized plastic zone overlapped. With given geometry and stratigraphic condition in this study, the safety or serviceability of the river embankment would hardly be affected since the ultimate settlement of the embankment after the twin-tunnel excavation is within the allowable limit. Reasonable tunnel face pressure and tail grouting pressure can to some extent suppress the settlement of the embankment. The recommended tunnel face pressure and tail grouting pressure are 300 kPa and 550 kPa in this study, respectively. However, the volume loss plays the crucial role in the tunnel-embankment interaction. Controlling and compensating the tunneling induced volume loss is the most effective measure for river embankment protection. Additionally, reinforcing the embankment with cement mixing pile in advance is an alternative option in case the predicted settlement exceeds allowable limit.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4D
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• pp.377-386
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• 2010

This study was conducted to find out the characteristics of the expanded road embankment constructed by the lightweight air-mixed soil (slurry density $10kN/m^3$) for a short-term without any ground improvement. Compression strength, capillary rise height of the lightweight air-mixed soil and settlement behavior of soft ground were studied. Compression strengths of the specimens sampled at the site after 1 and 5 months of construction were all satisfied the required strength 500 kPa. However, it was not convinced the homogeneity construction, because the values of strength were depending on the sampled location. Also, strength difference between laboratory and site specimens were found about 19%, and thus it should be considered for mixing design. Capillary rise reached about 20 cm for 70 hours because of a numerous tiny pores existed inside the lightweight air-mixed soil. Relationship between settlement and time of the soft ground placed underneath the expanded embankment was estimated by using the measured data and back analysis technique. The current average consolidation ratio and the final settlement after 120 months later were estimated about 32% and 4.5cm, respectively. This settlement is much less value than the allowable settlement 10cm for this structure.