• Title/Summary/Keyword: $Ca(OH)_2$

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Comparison of the Surface Chemical Properties of Plastic Film House, Upland, and Orchard Soils in Gyeongbuk Province

  • Park, Sang-Jo;Park, Jun-Hong;Kim, Chan-Yong;Seo, Young-Jin;Kwon, Oh-Heun;Won, Jong-Gun;Lee, Suk-Hee
    • Korean Journal of Soil Science and Fertilizer
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    • v.49 no.2
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    • pp.115-124
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    • 2016
  • The objectives of this study were to evaluate the soil fertility about plastic film house, upland, and orchard in Gyeongbuk Province, Korea. The surface chemical properties of soil samples were investigated every 4 year from 2000 year at upland, 2001 year at orchard, and 2002 year at plastic film house. During 12 year's monitoring, mean soil pH was increased by 0.7 and 0.8 pH unit from pH 5.7 in upland and orchard, respectively, 0.5 pH unit from pH 6.5 in plastic film house. About 50% of all the field samples occupied within the recommended pH range (pH 6-7). Although soil organic matter (SOM) was gradually increased by about $10g\;kg^{-1}$ for 12 years, 40% of orchard, 49% of plastic film house, and 77% of upland soil samples were still below the 3% SOM. The mean concentration of available phosphate for 12 years in upland, orchard, and plastic film house were 530, 600, and $760mg\;kg^{-1}$, respectively. The relative frequencies exceeding the recommended available phosphate range ($300-550mg\;kg^{-1}$) were 43%, 53%, and 66% at upland, orchard, and plastic film house soils, respectively. $NH_4OAc$ exchangeable $K^+$ of upland, orchard, and plastic film house in the last soil test were 0.8, 0.9, and $1.6cmol_c\;kg^{-1}$, respectively. The relative frequencies above the recommended K level were 56% and 70% of orchard and plastic film house soil samples, respectively. The levels of crop nutrients except exchangeable Ca and Mg in upland soil were tended to increase gradually in the three fields. Exchangeable Mg, EC, available phosphate, organic matter and soil pH could be used as principle components to differentiate the chemical properties of three land fields. This analysis revealed that the soil fertility was affected by cropping method and field management, although additional research is needed to assess the importance of management on soil chemical properties and many fields indicate an opportunity for improvement in fertilizer management.

The Experimental Study on The Compressive Strength of Concrete Using High Quality Recycled Fine Aggregate Produced by Sulphuric Water and Low Speed Wet Abrasional (황산수와 저속습식마쇄기로 생산된 고품질 순환 잔골재의 콘크리트 압축강도에 관한 실험적 연구)

  • Choi, Duck-Jin;Lee, Dae-Guen;Kim, Ha-Suk;Kawk, Eun-Gu;Kang, Chul;Kim, Jin-Man
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.11a
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    • pp.385-388
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    • 2008
  • Recycled fine aggregate has low quality because it contains large amount of old mortar. So, its usage is limited to a lower value-add, such as the roadbed material etc. Also, alkaline water occurred from treatment process of the waste concrete is becoming the cause of environmental problem. Accordingly, this study is to develop on the high quality recycled fine aggregate produced by low speed wet abraser using sulphuric. We investigated the properties of compressive strength of the mortar which was manufactured using recycled fine aggregate containing calcined gypsum produced by earlier mentioned process. Test results indicate that concrete using recycled fine aggregate containing calcined gypsum is higher compressive strength than concrete using other sands.

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Effect of Fine Particle Cement and Recycled Aggregates as Alkali Activator on the Engineering Properties and Micro-Structure of High Volume Blast Furnace Slag Concrete (알칼리 자극제로서 미분시멘트와 순환골재가 고로슬래그 다량치환 콘크리트의 공학적 특성 및 미세구조에 미치는 영향)

  • Han, Min-Cheol;Lee, Hyang-Jae;Han, Cheon-Goo
    • Journal of the Korea Institute of Building Construction
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    • v.13 no.6
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    • pp.602-608
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    • 2013
  • The aim of this study is to investigate experimentally the effect of the combination of fine particle cement with high Blaine fineness (FC) and recycled aggregates on the engineering properties and micro structure of high volume blast furnace slag (BS) concrete with 75% BS and 21 MPa. FC manufactured by particle classification at the plant with Blaine fineness of more than $7000cm^2/g$ was used as additional alkali activator for high volume blast furnace slag concrete made with recycled fine and coarse aggregates. FC was replaced by 15, 20 and 25% OPC. Test results showed that the incorporation of FC resulted in an increase in the compressive strength compared to BS concrete without FC by as much as 30% due to accelerated hydration and associated latent hydraulic reaction. It was found that the use of FC and recycled aggregates played an important role in activating BS for high volume BS concrete by offering sufficient alkali.

Influence of Aggregation Pheromone of Riptortus clavatus (Heteroptera: Alydidae) on the Occurrence of Egg Parasitoid, Gryon japonicum (Hymenoptera: Scelionidae) (톱다리개미허리노린재의 집합페로몬이 노린재검정알벌의 발생에 미치는 영향)

  • Paik, Chae-Hoon;Kang, Seok-Min;Jeon, Yong-Kyun;Lee, Geon-Hwi;Choi, Man-Young;Oh, Young-Jin;Park, Chung-Gyoo;Hwang, Chang-Yeon
    • Korean journal of applied entomology
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    • v.48 no.1
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    • pp.67-72
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    • 2009
  • The kairomonal activity of the aggregation pheromones of Riptortus clavatus for the egg parasitoid, Gryon japonicum, were investigated in soybean field. The parasitism rate of G. japonicum gradually decreased when the distances between pheromone traps and egg sites were increased from 0 to 15 m. The active distance of pheromone source for parasitoid attraction was estimated to be ca. 15 m. Under field conditions, the parasitoid wasp population peaked during the late August and early September, and the parasitism rate increased when the number of pheromone traps was increased from one to three per $165\;m^2$. However, insecticide-treated plots, the level of parasitism recorded is relatively low. Sex ratios in field populations of G. japonicum were female-biased.

Mineralogy and Geochemistry of Green-colored Cr-bearing Sericite from Hydrothermal Alteration Zone of the Narim Gold Deposit, Korea (나림 금광상의 열수변질대에서 산출되는 녹색크롬-견운모의 광물학적 및 지구화학적 특징)

  • Lee, Hyun Koo;Lee, Chan Hee
    • Economic and Environmental Geology
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    • v.30 no.4
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    • pp.279-289
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    • 1997
  • Dark to pale green-colored, Cr-bearing sericites from hydrothermal alteration zone of the Narim gold deposit were investigated mineralogically and geochemically. The alteration zone is composed mineralogically of quartz, carbonate minerals and green sericite with minor amounts of chlorite, barite and sulfide minerals (pyrite, sphalerite, galena). The zone is enriched in As (967 to 1520 ppm), Cu (31 to 289 ppm), Ni (1027 to 1205 ppm), Pb (0.20 to 1.24 wt.%) and Zn (1.03 to 1.07 wt. %) compared with fresh rocks such as granitic gneiss, porphyritic biotite granite and basic dyke. The Cr, probably the chromophore element, is highly enriched in the alteration zone (1140 to 1500 ppm), host granitic gneiss (1200 ppm) and porphyritic biotite granite (1200 ppm). Occurrence and grain size of sericite are diverse, but most of the Cr-bearing sericites (150 to $200{\mu}m$ long and 20 to $30{\mu}m$ wide) occur along the boundaries between ore veins and host rocks (especially basic dyke and granitic gneiss). X-ray diffraction data of the sericite show its monoclinic form with unit-cell parameters of $a=5.202{\AA}$, $b=8.994{\AA}$, $c=20.103{\AA}$, ${\beta}=95.746^{\circ}$ and $V=935.83{\AA}^3$, which are similar with the normal 2M1-type muscovite. Representative chemical formula of the sericite is ($K_{1.54}Ca_{0.03}Na_{0.01}$)($Al_{3.42}Mg_{0.38}Cr_{0.14}Fe_{0.06}V_{0.02}$)($Si_{6.69}Al_{1.31}$)$O_{20}(OH)_4$. The Cr content increases with decrease of the octahedral Al content, and ranges from 0.36 to 2.58 wt.%. DTA and TG curves of the sericite show endothermic peaks at $342^{\circ}$ to $510^{\circ}$, $716^{\circ}$ to $853^{\circ}$ and $1021^{\circ}C$, which are due to the expulsion of hydroxyl group. The total weight loss by heating is measured to be about 8.8 wt. %, especially at $730^{\circ}C$. Infrared absorption experiments of the sericite show broad absorption band due to the O-H bond stretching vibration near the $3625cm^{-1}$, coupled with the 825 and $750cm^{-1}$ doublet. The vibration bands related with the H-O-Al and Si-O-Al bonds occur at $1030cm^{-1}$ and 500 to $700cm^{-1}$, respectively. Based on paragonite content of the sericite, the formation temperature of the Narim gold deposit is calculated to be $220{\pm}10^{\circ}C$.

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Effects of Gami-Cheongpyesagan-Tang on Body Fat in High Fat Diet-Fed Obese Mice (가미청폐사간탕(加味淸肺瀉肝湯)이 고지방식이 비만생쥐의 체지방에 미치는 영향)

  • Keum, Seon-Oh;Lee, Ha-Il;Lee, Jong-Ha;Yoon, Yong-Il;Kwon, Young-Mi;Song, Yung-Sun
    • Journal of Korean Medicine for Obesity Research
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    • v.15 no.2
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    • pp.75-92
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    • 2015
  • Objectives: This study was designed to investigate the effect of Gami-cheongpyesagan-tang extract (GCST) on high fat diet-induced obesity in rats. Methods: The mice were divided into six groups; normal diet control, high fat diet control (HFD), HFD+GCST administrated group (100, 200, and 400 mg/kg) and olistat-admistrated group. Obesity was induced by high fat diet (45%) for 7 weeks in mice, and GCST was administrated orally every day for 7 weeks. The body weight, food intake, and serological markers such as total cholesterol, triglyceride, lipid contents, leptin, adiponectin and glutamic oxaloacetic transaminase/glutamic pyruvic transaminase were measured in mice. The mRNA expression of obese-associating genes such as sterol regulatory element-binding protein (SREBP)-1c, fatty acid synthase (FAS), stearoyl-CaP desaturase (SCD-1), peroxisome proliferator-activated receptor $(PPAR)-{\alpha}$, COA oxidase (ACO), and carnitine palmitoyltransferase ($CPT-1{\alpha}$) was analyzed by reverse transcription polymerase chain reaction. Results: The administration of GCST at 400 mg/kg, significantly reduced the increase of body weight and food intake as well as food efficiency compared to HFD group. GCST decreased the serum levels of triglyceride, total cholesterol, low-density lipoprotein-cholesterol, leptin in HFD control group and inhibited lipid accumulation in liver and adipose tissues, but did not increase high-density lipoprotein-cholesterol. In the liver tissues of GCST administrated HFD group, the mRNA levels of SREBP-1c, FAS and SCD-1 were decreased and the mRNA levels of $PPAR-{\alpha}$, ACO, and $CPT-1{\alpha}$ were increased. Conclusions: These results indicate that GCST could improve high fat diet induced obesity through inhibiting the hyperlipidemia in fatty Liver. It suggest that GCST may be used clinically for declining the accumultion of body fat with hyperlipidemia.

The Experimental Study on The Compressive Strength of Mortar Using High Quality Recycled Fine Aggregate Produced by Sulphuric Water and Low Speed Wet Abraser (황산수와 저속습식마쇄기로 생산된 고품질 순환 잔골재의 모르타르 압축강도에 관한 실험적 연구)

  • Choi, Duck-Jin;Lee, Dae-Guen;Han, Sang-Il;Kim, Ha-Suk;Jun, Myong-Hun;Kim, Jin-Man
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.485-488
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    • 2008
  • Recycled fine aggregate has low quality because it contains large amount of old mortar. So, its usage is limited to a lower value-add, such as the roadbed material etc. Also, alkaline water occurred from treatment process of the waste concrete is becoming the cause of environmental problem. Accordingly, this study is to develop on the high quality recycled fine aggregate produced by low speed wet abraser using sulphuric. We investigated the properties of compressive strength of the mortar which was manufactured using recycled fine aggregate containing calcined gypsum produced by earlier mentioned process. Test results indicate that mortar using recycled fine aggregate containing calcined gypsum has lowest compressive strength. It seems that low compressive strength is closely associated with the expansion of the specimen by excessive formation of ettringite.

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Studies on the Induction of Available Mutants of Takju Yeast by UV light Irradiation (part 2) -On the Physiological Characteristics of the Mutants- (자외선조사(紫外線照射)에 의한 탁주효모(酵母)의 변이주육성(變異株育成)에 관한 연구 (제 2 보) -변이주(變異株)의 생리적성질(生理的性質)에 관하여)

  • Kim, Chan-Jo;Oh, Man-Jin;Kim, Seung-Yul
    • Applied Biological Chemistry
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    • v.18 no.1
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    • pp.16-22
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    • 1975
  • This experiment was carried out to investigate the physiological characteristics of two original yeasts, 5-Y-5 and 6-Y-6, which selected from 24 Takju yeasts and three mutants, 30-24,30-81 and 40-27. induced from two original yeasts by the irradiation of UV light. The results were summarized as follows. 1) Alcohol tolerances of three mutants were decreased in some degree as compared with those of original yeasts. 2) Tolerances of lactic and citric acids of acid producing mutant 30-81, was increased than those of original yeasts. 3) In the case of using ammonium sulfate as a nitrogen source, two original yeasts and three mutants required Ca-pantothenate as a essential growth factor and four strains of yeasts except the mutant, 30-81, required biotin as a stimulated growth factor, When asparagine was used as a nitrogen source, two original yeasts and three mutants showed the same as above result but the stimulated effect of biotin was far less. 4) Propagation powers of the mutants were weaken than those of original yeasts, particular that of acid producing mutant, 30-81, was the weakest in the three mutants. 5) The optimum temperature for fermentation of original yeasts were $30^{\circ}C\;to\;35^{\circ}C$ but three mutants were $25^{\circ}C\;to\;30^{\circ}C$. 6) The optimum pH for fermentation of original yeasts were pH 5 to 6, and there is no appreciable difference between original yeasts and three mutants. The fermentation power of mutant,30-81, was decreased more rapidly than those of other mutants according to approach neutral. Three mutants were more sensible to heat than original yeasts. 7) Two original yeasts and three mutants were inhibited more over 20 percent of sugar for fermentation and three mutants were more sensible to sugar concentration than original yeasts.

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Comparison of Intensity Modulated Radiation Therapy Dose Calculations with a PBC and AAA Algorithms in the Lung Cancer (폐암의 세기조절방사선치료에서 PBC 알고리즘과 AAA 알고리즘의 비교연구)

  • Oh, Se-An;Kang, Min-Kyu;Yea, Ji-Woon;Kim, Sung-Hoon;Kim, Ki-Hwan;Kim, Sung-Kyu
    • Progress in Medical Physics
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    • v.23 no.1
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    • pp.48-53
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    • 2012
  • The pencil beam convolution (PBC) algorithms in radiation treatment planning system have been widely used to calculate the radiation dose. A new photon dose calculation algorithm, referred to as the anisotropic analytical algorithm (AAA), was released for use by the Varian medical system. The aim of this paper was to investigate the difference in dose calculation between the AAA and PBC algorithm using the intensity modulated radiation therapy (IMRT) plan for lung cancer cases that were inhomogeneous in the low density. We quantitatively analyzed the differences in dose using the eclipse planning system (Varian Medical System, Palo Alto, CA) and I'mRT matirxx (IBA, Schwarzenbruck, Germany) equipment to compare the gamma evaluation. 11 patients with lung cancer at various sites were used in this study. We also used the TLD-100 (LiF) to measure the differences in dose between the calculated dose and measured dose in the Alderson Rando phantom. The maximum, mean, minimum dose for the normal tissue did not change significantly. But the volume of the PTV covered by the 95% isodose curve was decreased by 6% in the lung due to the difference in the algorithms. The difference dose between the calculated dose by the PBC algorithms and AAA algorithms and the measured dose with TLD-100 (LiF) in the Alderson Rando phantom was -4.6% and -2.7% respectively. Based on the results of this study, the treatment plan calculated using the AAA algorithms is more accurate in lung sites with a low density when compared to the treatment plan calculated using the PBC algorithms.

The Dose Attenuation according to the Gantry Angle and the Photon Energy Using the Standard Exact Couch and the 6D Robotic Couch (Standard Exact Couch와 6D Robotic Couch를 이용한 광자선의 조사각에 따른 선량 감쇠에 대한 연구)

  • Kim, Tae Hyeong;Oh, Se An;Yea, Ji Woon;Park, Jae Won;Kim, Sung Kyu
    • Progress in Medical Physics
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    • v.27 no.2
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    • pp.79-85
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    • 2016
  • The objective of this study is to increase the accuracy of dose transmission in radiation therapy using two types of treatment tables, standard exact couch (Varian 21EX, Varian Medical Systems, Milpitas, CA) and 6D robotic couch (Novalis, BrainLAB A.G., Heimstetten, Germany)). We examined the dose attenuation based on the two types of treatment tables and studied the dose of attenuation using the phase (In/Out) for the standard exact couch. We measured the relative dose according to the incident angle of a penetrative photon beam under a treatment table. The incident angle of the photon beam was from $0^{\circ}$ to $360^{\circ}$ in the increments of $5^{\circ}$. The reference angle was set to $0^{\circ}$. Furthermore, the relative dose of the 6D robotic couch was measured using 6 MV and 15 MV, and that of the standard exact couch was measured at the sliding rail position (In-Out) using 6 MV and 10 MV. In the case of the standard exact couch, the measured relative dose was 16.53% (rails at the "In position," $175^{\circ}$, 6 MV), 12.42% (rails at the "In position," $175^{\circ}$, 10 MV), 13.13% (rails at the "Out position," $175^{\circ}$, 6 MV), and 9.96% (rails at the "Out position," $175^{\circ}$, 10 MV). In the case of the 6D robotic couch, the measured relative dose was 6.82% ($130^{\circ}$, 6 MV) and 4.92% ($130^{\circ}$, 15 MV). The photon energies were surveyed at the same incident angle. The dose attenuation for an energy of 10 MV was 4~5% lower than that for 6 MV. This indicated that the higher photon energy, lesser is the attenuation. The results of this study indicated that the attenuation rate for the 6D robotic couch was confirmed to be 1% larger than that for the standard exact couch at 6 MV and $180^{\circ}$. In the case of the standard exact couch, the dose attenuation was found to change rapidly in accordance with the phase ("In position" and "Out position") of the sliding rail.