• Textile Coloration and Finishing
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• v.27 no.3
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• pp.210-218
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• 2015

In this study, natural substance and mineral materials was used for architectural interior wallpaper. Because natural substance and minerals are environment-friendly material with moisture adsorption and desorption properties. Natural substance and mineral materials was evaluated in moisture adsorption and desorption properties. Also, in the diatomite, the pores were observed on SEM photographs. Thus, it is supposed that moisture adsorption and desorption properties were influenced by the microstructure of the pore. The wallpaper according to the ratio of the mixture was analyzed for physical properties and moisture adsorption & desorption properties. As a result, we developed a wallpaper having excellent hygrothermal performance.

• Journal of the Korean Wood Science and Technology
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• v.48 no.4
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• pp.488-502
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• 2020

In this study, the moisture absorption and desorption properties presented by the Health-Friendly Housing Construction Standards of South Korea were compared using the wood of three tree species (Douglas-fir, Hinoki, Larch) and two types of wood-based materials(Plywood, WML Board^Ⓡ). The national standards for functional building materials present that the amounts of moisture absorption and desorption should be at least 65g/㎡ on average, respectively according to the test method under KS F 2611:2009. Therefore, in this study, the moisture absorption/desorption properties of materials with no treatment (Control), with punching, and with surface stain finishing and the moisture absorption/desorption property improvement effects of the treatments were compared and analyzed. According to the results of this study, it was evaluated that all five types of wood and wood-based materials tested did not satisfy the amount of moisture absorption/desorption of at least 65g/㎡, which is the performance standard for moisture absorption/desorption functional building materials, indicating that untreated wood and wood-based materials cannot be applied as functional finishing materials according to the Health-Friendly Housing Construction Standards. The surface stain finishing greatly reduced the moisture absorption and desorption rates of the materials, and the amounts of moisture absorbed and desorbed were also shown to decrease by at least two times on average. When the surfaces of the materials were punched with Ø4mm holes at intervals of 20 mm, the moisture absorption/desorption areas increased from 18% to 51%, and this increase was shown to be capable of increasing the amounts of moisture absorbed/desorbed by 29% on average at the minimum, and 81% on average at the maximum. The effects of punching were shown to be identical even in cases where the materials were stain finished. For the application of wood or wood-based materials as eco-friendly, health-friendly, and moisture absorption/desorption functional building materials hereafter, it is judged that new physical and chemical improvement studies should be conducted, and treatment methods should be developed.

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.145.1-145
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• 1998

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.111-114
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• 2001

Thermal desorption process is valuable for the remediation of oil contaminated site. The system is physical separation process by volatizing oil contaminants from soil matrixes and is not designed to provide high levels of oil destruction. The process is not incineration, because the decomposition of oil materials is not the desired result, although some decomposition may occur. The physical and chemical properties that influence the design and operation of the system include boiling points, soil sorption characteristics, aqueous phase solubility, thermal stability, contaminating oil concentration, moisture contents, particle size distribution and etc.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1253-1257
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• 2011

The surface structures, adsorption conditions, and thermal desorption behaviors of cyclopentanethiol (CPT) self-assembled monolayers (SAMs) on Au(111) were investigated by scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), and thermal desorption spectroscopy (TDS). STM imaging revealed that although the adsorption of CPT on Au(111) at room temperature generates disordered SAMs, CPT molecules at $50^{\circ}C$ formed well-ordered SAMs with a $(2{\surd}3{\times}{\surd}5)R41^{\circ}$ packing structure. XPS measurements showed that CPT SAMs at room temperature were formed via chemical reactions between the sulfur atoms and gold surfaces. TDS measurements showed two dominant TD peaks for the decomposed fragments ($C_5H_9^+$, m/e = 69) generated via C-S bond cleavage and the parent molecular species ($C_5H_9SH^+$, m/e = 102) derived from a recombination of the chemisorbed thiolates and hydrogen atoms near 440 K. Interestingly, dimerization of sulfur atoms in n-alkanethiol SAMs usually occurs during thermal desorption and the same reaction did not happen for CPT SAMs, which may be due to the steric hindrance of cyclic rings of the CPT molecules. In this study, we demonstrated that the alicyclic ring of organic thiols strongly affected the surface structure and thermal desorption behavior of SAMs, thus providing a good method for controlling chemical and physical properties of organic thiol SAMs.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.6
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• pp.1045-1053
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• 2000

The adsorption and desorption of herbicides such as napropamide and pendimethalin was studied in three kinds of soil. sandy loam. silty clay and loam. The results of batch tests performed with various shaking time, pH, organic matter content and temperature in soil were summarized as follows. The shaking times reached to the equilibrium of the adsorption and desorption for napropamide and pendimethalin in soil were 12 and 6 hours. respectively. For each soil. the adsorption rates of napropamide were 23.35%. 31.57% and 25.95%, the desorption rates of them were 18.42%, 13.42% and 15.89%, respectively. And the adsorption rates of pendimethalin were 59.61%, 77.26% and 64.02%, and the desorption rates of them were 3.23%, 2.93% and 3.07%, respectively. The adsorption isotherms with the Freundlich equation showed better consistency than those with the Langmuir one. The adsorption was affected by the organic matter content when it exceed 2.0%. But if the organic matter content is below 2.0%, it was affected by the clay content. When the organic matter content is 0.95~7.45%, the adsorption coefficients ($K_{fa}$) of napropamide and pendimethalin were 1.17~2.50 and 4.74~16.08 and the desorption coefficients($K_{fd}$) of them were 5.33~34.06 and 24.25~134.00, respectively. Because of the physical adsorption between herbicide molecules and soil surface, little effect of pH variation of soils was appeared for the adsorption and desorption. Because of the solubility of herbicide is related to the temperature, the adsorption rate was decreased and the desorption rate was increased with the temperature increase, respectively.

• Journal of Soil and Groundwater Environment
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• v.13 no.5
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• pp.81-87
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• 2008

In accompany with the transfer of US army bases, recent surveys reported serious contamination of soils by the release of petroleum from storage facilities and heavy metals accumulated in rifle-ranges. These problems have made an increased concerns of cleanup technology for contaminated soils. In this study, a full-scale soil washing process improved by multistage continuous desorption and agitational desorption techniques was examined for petroleum-contaminated soils obtained from three different remedial sites that contained 29.3, 16.6, and 7.8% of silt and clay, respectively. The initial concentrations of total petroleum hydrocarbon (TPH) were 5,183, 2,560, and 4,860 mg/kg for each soil. Pure water was applied to operate washing process, in which water used for washing process was recycled 100% for over 6 months. The results of full-scale washing tests showed that the TPH concentrations for soils (> 3.0 mm) were 50${\sim}$356 mg/kg (85.2${\sim}$98.2% removal rates), regardless of the contents of silt and clay from in A, B and C soil, when the soils were washed at 3.0 kg/$cm^2$ of injection pressure with the method of wet particle separation. Based on the initial TPH concentration, the TPH removal rates for each site were 85.2, 98.2 and 89.9%. For soils in the range of 3.0${\sim}$0.075 mm, the application of first-stage desorption technique as a physical method resulted 834, 1,110, and 1,460 mg/kg of TPH concentrations for each soil, also additional multi-stage continuous desorption reduced the TPH concentration to 330, 385, and 245 mg/kg that were equivalent to 92.4, 90.6, and 90.1% removal rates, respectively. The result of multi-stage continuous desorption for fine soil (0.075${\sim}$0.053 mm) were 791, 885, and 1,560 mg/kg, and additional agitation desorption showed 428, 440, and, 358 mg/kg of TPH concentrations. Compared with initial concentration, the removal rates were 92.0, 93.9 and 92.9%, respectively. These results implied we could apply strategic process of soil washing for varies types of contaminated soils to meet the regulatory limit of TPH.

• Journal of Environmental Science International
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• v.8 no.2
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• pp.249-254
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• 1999

The biosorption and desorption of Cd were carried out using brown marine algae, known as the good biosorbent of heavy metals. The content of alginate bound to light metals could be changed by the physical and the chemical pretreatment of Sargassum fluitans biomass. The Cd uptake was independent of the alginate content. In case of protonated biomass, Cd uptake was the lowest because the alginic acid of biomass was dissolved to cadmium solution during the biosorption. The maximum Cd uptake of Sargassum biomass was ranged from 79 mg/g to 139 mg/g. In case of raw biomass, the higher the alginate content of biomass, the higher was the Cd uptake. 100% of Cd and light metals sorbed in the biomass were eluted at 0.1N HCI(pH 1.1). However, the elution efficiency in $CaCl_2$ and $Ca{(NO_3)}_2$solution was varied by the concentration, the solid to liquid ratio and the pH of calcium solution. The distribution coefficient between Cd and protons in the desorption solution at pH ranged from 1.6 to 2.9 was observed on the constant stoichometric coefficient(1.3).

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.198-198
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• 2013

Metal-Oxide-Semiconductor (MOS)에서 사용되는 다양한 channel materials로 high electron mobility을 가지는 III-V compound semiconductor가 대두되고 있다 [1,2]. 하지만 이러한 III-V compound semiconductor는 Si에 비해 안정적인 native oxide가 부족하기 때문에 Si, Ge, Al2O3과 BeO 등과 같은 다양한 물질들의 interface passivation layers (IPLs)에 대한 연구가 많이 되고 있다. 이러한 IPLs 물질은 0.5~1.0 nm의 매우 얇은 physical thickness를 가지고 있고 또한 chemical inert하기 때문에 플라즈마 식각에 대한 연구가 되고 있지만 IPLs 식각 후 기판인 III-V compound semiconductor에 physical damage과 substrate recess를 줄이기 위해서 높은 선택비가 필요하다. 이러한 식각의 대안으로 원자층 식각이 연구되고 있으며 이러한 원자층 식각은 반응성 있는 BCl3의 adsorption과 low energy의 Ar bombardment로 desorption으로 self-limited한 one monolayer 식각을 가능하게 한다. 그러므로 본 연구에서는, III-V compound semiconductor 위에 IPLs의 adsorption과 desorption의 cyclic process를 이용한 원자층식각으로 다양한 물질인 SiO2, Al2O3 (self-limited one monolayer etch rate=about 1 ${\AA}$/cycle), BeO (self-limited one monolayer etch rate=about 0.75 ${\AA}$/cycle)를 얻었으며 그 결과 precise한 etch depth control로 minimal substrate recess 식각을 할 수 있었다.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.5
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• pp.575-584
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• 2007

The adsorption capability of iron phthalocyanine derivatives were investigated by means of X-ray diffractometor (XRD), IR (infrared) spectroscopy, scanning electron microscopy (SEM) and temperature programmed desorption (TPD). According to TPD results, iron phthalocyanine derivatives showed two desorption peaks at low temperature ($100{\sim}150^{\circ}C$) and high temperature ($350{\sim}400^{\circ}C$) indicating that there were two kinds of acidities. Tetracarboxylic iron phthalocyanine (Fe-TCPC) have a stronger desorption peak (chemical adsorption) at the high temperature and a weaker desorption peak (physical adsorption) at the low temperature than iron phthalocyanine (Fe-PC). The specific surface areas of Fe-TCPC and Fe-PC were $26.46\;m^2/g\;and\;11.77\;m^2/g$, respectively. The pore volumes of Fe-TCPC and Fe-PC were $0.14\;cm^3/g\;and\;0.06\;cm^3/g$, respectively. The adsorption capability of triethyl amine calculated by breakthrough curve at 220 ppm of equilibrium concentration was 29.2 mmoL/g for Fe-TCPC and 0.8 mmoL/g for Fe-PC. The removal efficiency of dimethyl sulfide of Fe-TCPC and Fe-PC in batch experiment of 225 ppm of initial concentration were 44.9% and 28.9%, respectively. The removal efficiency of trimethyl amine of Fe-TCPC and Fe-PC in batch experiment of 118 ppm of initial concentration were approximately 100.0% and 33.9%, respectively.