• Wind and Structures
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• v.22 no.5
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• pp.555-571
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• 2016

A hanging-type sand-retaining wall is a very common sand-blocking fence structure used to prevent sand movement. This type of wall is widely used along the Qinghai-Tibet and Gobi desert railways in Xinjiang, Western China. To analyze the characteristics of wind-sand flow fields under the effect of such a sand fence structure, a wind tunnel test and a field test were carried out. The wind tunnel test showed the zoning characteristics of the flow fields under the effect of the hanging-type sand-retaining wall, and the field test provided the sediment transport data for effective wind-proof interval and the sand resistance data in the front and behind the sand-retaining wall. The consistency of the wind-sand flow fields with the spatial distribution characteristic of wind-carried sand motion was verified by the correspondences of the acceleration zone in the flow field and the negative elevation points of the percentage variations of the sand collection rate. The spatial distribution characteristic of the field sand collection data further showed the spatial structural characteristic of the sandy air currents under the action of the hanging-type sand-retaining wall and the sand resistance characteristic of the sand-retaining wall. This systematic study on the wind-sand flow fields under the control of the hanging-type sand-retaining wall provides a theoretical basis for the rational layout of sand control engineering systems and the efficient utilization of a hanging-type sand-retaining wall.

• Membrane and Water Treatment
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• v.6 no.3
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• pp.225-235
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• 2015

During low-pressure membrane treatments of cyanobacterial cells, including microfiltration (MF) and ultrafiltration (UF), there have reportedly been releases of intracellular compounds including cyanotoxins and compounds with an earthy-musty odor into the water, probably owing to cyanobacterial cell breakage retained on the membrane. However, to our knowledge, no information was reported regarding the effect of growth phase of cyanobacterial cells on the release of the intracellular compounds. In the present study, we used a geosmin-producing cyanobacterium, Anabaena smithii, to investigate the effect of the growth phase of the cyanobacterium on the release of intracellular geosmin during laboratory-scale MF experiments with the cells in either the logarithmic growth or stationary phase. Separate detection of damaged and intact cells revealed that the extent of cell breakage on the MF membrane was almost the same for logarithmic growth and stationary phase cells. However, whereas the geosmin concentration in the MF permeate increased after 3 h of filtration with cells in the logarithmic growth phase, it did not increase during filtration with cells in the stationary phase: the trend in the geosmin concentration in the MF permeate with time was much different between the logarithmic growth and stationary phases. Adsorption of geosmin to algogenic organic matter (AOM) retained on the MF membrane and/or pore blocking with the AOM were greater when the cells were in the stationary phase versus the logarithmic growth phase, the result being a decrease in the apparent release of intracellular geosmin from the stationary phase cells. In actual drinking water treatment plants employing membrane processes, more attention should be paid to the cyanobacterial cells in logarithmic growth phase than in stationary phase from a viewpoint of preventing the leakage of intracellular earthy-musty odor compounds to finished water.

• Journal of the Korean Solar Energy Society
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• v.39 no.6
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• pp.127-135
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• 2019

In this study, we analyzed the relationship between five factors: long-wave radiation, short-wave radiation, cloudiness, SVF and summer shelters. In the previous study, we recognized the correlation between single building SVF and long-wave radiation. Furthermore, this study attempted to confirm the relationship at the summer shelter with high solar radiation blocking rate. The observations are as follows. ① Cooling in summer shelters was not the effect of temperature but the effect of radiation reduction due to short-wave radiation shielding. ② In the case of the canopy tent with low heat capacity, the long-wave radiation was observed to be 16.7% higher per hour than the comparison control point due to the increase in surface temperature. ③ The long-wave radiation increase rate was different according to SVF, but showed very similar pattern according to the material characteristics of the summer shelters. ④ Passive Cooling effect on the type of summer shelters are determined by the size of the total long and short-wave radiation at that point.

• YAKHAK HOEJI
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• v.22 no.3
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• pp.163-174
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• 1978

Plantaginis seed has been applied in Chinese medicine a as well as in folk remedy. It was advocated that Plantaginis S Semeη exerts good therapeutic effects as anti-inflammatory, antitussive, obstipant and diuretic agent in some cases of alimentary, respiratory a and renal disorders. This study was carried out in order to r re-evaluate the pharmacological action, especially the hypotensive a action of Plantaginis Semen and to elucidate the mechanism of its a action, making use of Plantaginis Semen methanol extract (PME), because its basic pharmacological action, i. e., hypotensive action is n not clear. 1) PME, when administered into intravenous route, elicited the h hypotensive response dependent on the dose of PME given to the rabbit anesthetized with urethane. 2) This hypotensive response of P PME was inhibited by atropine and potentiated by physostigmine, but not influ$\varepsilon$need by vagotomization. 3) Depressor effect of PME was blocked by chlorisondamine, phentolamine, and bethanicline, while not altered by cyproheptadine, diphenhydramine and propran¬olol. 4) The secondary pressor response after blocking the depressor e effect of PME by chlorisondamine was produced, but this pressor response was deminished by atropine. 5) PME augmented the pressor e effect of norepinephrine and angiotensin, on the other hand, reduced b blood pressure elevated by carotid occlusion reflex. 6) These observa¬t tions suggest that PME may induce the hypotensive response via dual mechanisms of parasympathomimetic and sympatholytic action, that the positions of this action are cholinergic peripheral site and sympathetic ganglia respectively, and that PME may possess the pressor activity caused by stimulation of "atropine-sensitive site" which seems to existsin the sympathetic ganglia.

• Journal of Environmental Impact Assessment
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• v.21 no.1
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• pp.25-39
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• 2012

This study was aimed to assess the effects of additional installation of two different types of weirs, one is a curtain-type weir and another is a submerged-type weir, on the control of algal growth in Daechung Reservoir. A two-dimensional(2D) coupled hydrodynamic and eutrophication model that can accommodate vertical movement of the curtain weir following the water surface variations was verified using field data obtained in two distinctive hydrological years; dry(2008) and wet(2010). The model adequately simulated the temporal and spatial variations of water temperature, nutrients and algal(Chl-a) concentrations during the periods. The effectiveness of curtain weir on the control of algal bloom was evaluated by applying the model to 2001(dry year) and 2010 assuming 6 different scenarios according to installation locations. The curtain weirs that already installed at 3, 5, 7 sites(scenario C-2) showed significant effect on the control of algal growth in the reservoir; the reduction rates of algal concentration were placed in the range of 7.5~31.5% and 9.1~44.9% for 2001 and 2010, respectively. However the simulation results revealed that additional installation of curtain weirs(scenario C-3~C-6) in the bay area (choosori) have marginal effect. The effectiveness of submerged weir was evaluated against 2010 assuming 7 different scenarios according to installation locations, but all scenarios(S-1~S-7) showed neglectable or negative effect on the control of algal growth.

• Membrane Journal
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• v.30 no.2
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• pp.131-137
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• 2020

In this study, effect of inorganic particles on organic fouling was investigated by a laboratory-scaled pressurized membrane filtration. In order to cause organic fouling, sodium alginate (SA) was used as a feed solution. Regardless of the presence of inorganic SiO₂ particles, the complete pore blocking played an important role in determining the fouling rate during the initial period of membrane filtration. However, the formation of cake layer resulted in the membrane fouling more dominantly as filtration time progressed. In the presence of inorganic particles, both specific cake resistance and compressibility associated with the membrane fouling formed were relatively lower than that without SiO₂ particles. Membrane fouling was more severe at constant flux mode of filtration than that observed at constant pressure mode probably due to the concomitant increase of compressibility of fouling layer with transmembrane pressure (TMP). It was found that the presence of SA and SiO₂ particles in feed solution provided the synergistic effect on the hydraulic backwashing to reduce membrane fouling as compared to the SA solution alone without the inorganic particles.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.4
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• pp.1031-1036
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• 2003

To certify the protective effect of herbal medicine against oxygen free radical-induced myocardiotoxicity, cytotoxicity was measured using TBARS assay and Beating rate in the presence of Tongryeong-san(TRS) extracts or single constituents of this prescription. Myocardial toxicity was evaluated in neonatal rat myocardiocytes in cultures. In the present study, xanthine oxidase/hypoxanthine (XO/HX) resulted in a increase in lipid peroxidation and decreases in beating rate in cultured myocardial cells. In the effect of TRS extract, it showed the prevention from the XO/HX-induced cardiotoxicity by the increases of beating rate as well as the decrease of lipid peroxidation, In the protective effect of Faeces Trogopterori(FT), Pollen Typhae(PT), Caulis Akebiae(CA) and Radix Paeoniae Rubra(PRR), all the extracts were significantly effective in the protection of XO/HX-induced cardiotoxocity in cultured myocardial cells by the increase of beating rate as well as th decrease of lipid peroxidation. From these results, they show that XO/HX is cardiotoxic in cultured myocardial cells derived from neonatal rat, and it suggests that TRS, FT, PT, CA and PRR extracts are positively effective in the blocking in XO/HX-induced cardiotoxicity.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.3
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• pp.617-625
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• 2007

Samul-Tang (SMT) has been used for nourishing of the blood, hematopoiesis as a herbal medicine history. The purpose of this study is to find out anti-allergic inflammatory reaction of SMT. To clarify the mechanism, the effect of SMT on vascular permeability of rat cutaneous tissue and histamine and cytokines (IL-6, IL-8, TNF-${\alpha}$) release from mast cells were observed. The results are the pretreatment with SMT significantly decreased the compound 48/80-induced degranulation and histamine release from RPMC, SMT also inhibited the anti-DNP lgE-induced increment of vascular permeability of rat cutaneous tissue. SMT significantly reduced the PMA plus A23187-induced increment of expression of IL-6, IL-8, and TNF-${\alpha}$ in HMC-1 Cell. The Present study provide evidence that SMT inhibits mast cell-derived inflammatory allergic reactions by blocking histamine release and pro-inflammatory cytokine expression, and suggest the mechanisms of action. Furthermore, in vivo and in vitro anti-allergic effect of SMT suggests a possible therapeutic application of this agent in inflammatory allergic diseases.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.337-347
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• 2006

Papers made from unbleached and bleached bagasse chemimechanical pulp were chemically modified by acetylation. The effects of irradiation on unbleached and bleached also reduced papers of bagasse chemimechanical pulp before and after acetylation were investigated in this study. Chemimechanical pulp was prepared from bagasse and then bleached with hydrogen peroxide. Unbleached and hydrogen bleached pulps were reduced by Sodium borohydride in different procedures. Paper sheets were prepared from pulps and then acetylated using a technical grade of acetic anhydride. Accelerated photo-aging was run on the samples using fluorescent lamps to verify photo-stability of paper sheets before and after pretreatments. Brightness reversion (as Post-color number) and other optical properties of the paper sheets were measured. Efficient inhibition of photo-yellowing of papers made from bagasse CMP was achieved by acetylation. The acetylated unbleached CMP was noticeably photo-bleached during irradiation. Sodium borohydride reduction followed by acetylation had the same effect as acetylation alone at the same degree of reaction time and reductive treatment did not affect the yellowing rate to any great extent. The pre-reduced, acetylated unbleached papers were, however, not brightened during irradiation. Calculation done by Kubelka-Munk equation showed that reductive treatment had little effect in reducing the photo-yellowing of paper made from CMP pulp; a small stabilization effect was observed in the case of bleached CMP, while unbleached CMP was slightly more prone to discolor in the later phase of photo-reversion. The improved stability towards light may was closely related to the decrease in the phenolic hydroxyl content as a result of blocking by acetyl groups during treatment with acetic anhydride. The results support the hypothesis that phenolic hydroxyl has an important role in the process of photo-reversion of high-yield pulps. The results obtained in this study demonstrate that the acetylation of paper manufactured from peroxide bleached Bagasse CMP significantly retards light-induced discoloration. The inhibition of yellowing is connected with a decrease in the phenolic hydroxyl content of both unbleached and peroxide bleached papers.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.65-65
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• 2019

In this study, we evaluated the anti-inflammatory effect of extracts of leaves (LCLE) and branches (LCBE) from L. caerulea in LPS-stimulated RAW264.7 cells. Inhibitory effect of LCLE and LCBE against LPS-induced overproduction of NO, iNOS and $IL-1{\beta}$ was higher than LCFE. Furthermore, LCLE and LCBE significantly inhibited the overexpression of COX-2, IL-6 and $TNF-{\alpha}$ in LPS-stimulated RAW264.7 cells. LCLE and LCBE did not inhibited LPS-induced degradation of $I{\kappa}B-{\alpha}$, but blocked the nuclear accumulation of p65. LCLE did not inhibited LPS-induced phosphorylation of ERK1/2 and p38, while LCBE significantly attenuated phosphorylation level of p38. LCLE and LCBE increased HO-1 protein level and decrease of iNOS and $IL-1{\beta}$ expression by LCLE and LCBE was inhibited by HO-1 knockdown. The inhibition of p38 by SB203580 and ROS by NAC blocked HO-1 expression by LCLE and LCBE. LCLE and LCBE increased p38 phosphorylation and the inhibition of ROS by NAC blocked p38 phosphorylation LCLE and LCBE. LCLE and LCBE induced nuclear accumulation of Nrf2, but this was significantly reversed by the inhibition of p38 and ROS. In addition, LCLE and LCBE increased ATF3 expression and decrease of iNOS and $IL-1{\beta}$ expression by LCLE and LCBE was inhibited by ATF3 knockdown. Collectively, LCLE and LCBE inhibited LPS-induced $NF-{\kappa}B$ activation by blocking p65 nuclear accumulation, increased HO-1 expression by ROS/p38/Nrf2 activation, and increased ATF3 expression. Furthermore, LCBE inhibited LPS-induced p38 phosphorylation.