• Title/Summary/Keyword: paste materials

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An Experimental Study on Mortar to Apply Building Structure (건축물 구조체에 적용가능한 모르타르에 관한 실험적 연구)

  • Kwon, Mi-Ok;Park, Heung-Lee;Kwon, Hee-Sung;Kim, Sung-Jin;Lim, Nam-Ki;Jung, Sang-Jin
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2008.05a
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    • pp.83-86
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    • 2008
  • The concrete used most in construction materials. There is an overcrowded iron dimensions use of the concrete at time of the other concrete theory on the reinforcing rod back which did congestion and compares it with this, and there are more few dimensions of the aggregate than concrete, and quantity of aggregate passage is superior in mortar than concrete. If a volume rate of the aggregate writes mortar than concrete against this, therefore, unit amount increases, and quantity of paste increases and quantity of dry shrinkage than increase concrete. However, I let I regulate lay priest distribution of the aggregate, and the results rates increase and reduce unit amount and decrease quantity of dry shrinkage, and separation resistance and the gap passage characteristics are judged because it can be it in a substitute document of very superior concrete. I came to carry out the study that I watched to let I was useful a little more and do the improvement repair of a become building wall body, a basement pillar and repair reinforcement of the assistant in the reinforcing rod back, the old age when I made congestion here. I regulated lay priest distribution of the aggregate in the study and regulated substitution rate of the aggregate (40%, 50%, 60%) and divided W/C 30%, 40% standards and produced mortar and I compared quantity of air by this, slump, compression robbery and showed it this time.

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Comparison of bond strengths of ceramic brackets bonded to zirconia surfaces using different zirconia primers and a universal adhesive

  • Lee, Ji-Yeon;Ahn, Jaechan;An, Sang In;Park, Jeong-won
    • Restorative Dentistry and Endodontics
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    • v.43 no.1
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    • pp.7.1-7.7
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    • 2018
  • Objectives: The aim of this study is to compare the shear bond strengths of ceramic brackets bonded to zirconia surfaces using different zirconia primers and universal adhesive. Materials and Methods: Fifty zirconia blocks ($15{\times}15{\times}10mm$, Zpex, Tosoh Corporation) were polished with 1,000 grit sand paper and air-abraded with $50{\mu}m$ $Al_2O_3$ for 10 seconds (40 psi). They were divided into 5 groups: control (CO), Metal/Zirconia primer (MZ, Ivoclar Vivadent), Z-PRIME Plus (ZP, Bisco), Zirconia Liner (ZL, Sun Medical), and Scotchbond Universal adhesive (SU, 3M ESPE). Transbond XT Primer (used for CO, MZ, ZP, and ZL) and Transbond XT Paste was used for bracket bonding (Gemini clear ceramic brackets, 3M Unitek). After 24 hours at $37^{\circ}C$ storage, specimens underwent 2,000 thermocycles, and then, shear bond strengths were measured (1 mm/min). An adhesive remnant index (ARI) score was calculated. The data were analyzed using one-way analysis of variance and the Bonferroni test (p = 0.05). Results: Surface treatment with primers resulted in increased shear bond strength. The SU group showed the highest shear bond strength followed by the ZP, ZL, MZ, and CO groups, in that order. The median ARI scores were as follows: CO = 0, MZ = 0, ZP = 0, ZL = 0, and SU = 3 (p < 0.05). Conclusions: Within this experiment, zirconia primer can increase the shear bond strength of bracket bonding. The highest shear bond strength is observed in SU group, even when no primer is used.

The Seasonal Microbiological Quality Assessment of Kimbap(seaweed roll) Production flow in Foodservice facilities for Univ. students - HACCP model - (대학생 대상 급식시설의 김밥 생산과정에 따른 계절별 미생물적 품질평가)

  • 이혜상;류승연
    • Korean journal of food and cookery science
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    • v.14 no.4
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    • pp.367-374
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    • 1998
  • The purpose of this study was to evaluate the microbiological quality of, and to assure the hygienic safety of, the kimbap production in the university foodservice facilities in accordance with the HACCP (Hazard Analysis Critical Control Point) Program. The time-temperature relationship and the microbiological quality (specifically, total plate count and coliform bacteria count) were assessed to find the critical control point (CCP) during each of the production phases. The average of the daily longest duration time of the kimbap at the facilities was 23.4 hours in summer, while 29.6 hours in winter. In the purchasing phase of the raw materials, the microbiological quality of laver, fish paste, carrot and cucumber in summer was not at an acceptable level according to the standard set by the Natick research center, especially the number of TPC and the coliform level of laver was higher than the threshold level. In the refrigerator storage phase, the temperature of the carrot was 7.4$^{\circ}C$. This temperature is far exceeding the standard so that the microbiological counts was increased by the 2 log cycle during the average storage time of 17 hours or more. In the preparation phase, the temperature of the blanching is too low compared to the standard. In the holding phase before serving, its time-temperature relationship was out of the FDA food code standard both in winter and summer. In the sewing phase, the number of microbiological count was higher than the threshold level in summer while that in winter was up to standard. According to the Harrigan and McCance standard, the number of microbiological count of the utensils was higher than the threshold level in summer while that in winter was up to standard.

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A Study on the Book "Gwngonsiuebang" ("규호시의방"의 정리학적 고찰)

  • 이효지
    • Journal of the Korean Home Economics Association
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    • v.19 no.2
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    • pp.189-198
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    • 1981
  • The Gwugonsiuebang is a book of Korean woman's life in the Yi dynasty which published I 1653 by Mme. Jang. I have studied the food habits of the Yi dynasty that wrote in Gwugonsiueband as following. The staple foods are Guksu (wheat vemicell as like western noodles) 5, Mandu (bun stuffed with seasoned meat and vegetables) 6 kinds in this book. the side dishes are Guk (soup) 8, J'm (steamed meat or fish) 6, chae6, Nooruemi 5, Hyae (sliced raw fish) 3, Jockpyun (jellied beef soup) 3, Jockgall (salted sea food) 2, Jock (skewer or broach) 2, jihee 2, Sun (Steaming of stuffed vegetable) 1, Bockuem (saute) 1, Jon (pan fried fish) 1, Gui (meat or fish grilled with seasoning) 1, and the other 13 kinds. The desserts are D,ock (Korean rice cake) 11, jabgwa 8, Beverages 5 kinds and Jungwa 1 kind. The alcohol and fruits wine are 51 kinds. The alcohol and fruits wine are 51 kinds. The seasonings are Soybean sauce, oil, Sesamol oil, pepper, Ginger, Garlic, Vinegar, Wine, Salt, Bean paste etc. Raw materials of Guksu, Mandu, D'ock, Jabgwa, Beverage, Wine, vinegar are all carbohydrates. It shows that a tendency of Korean people too much take a carbohydrates. Now and then, there are no special difference of winter over pass for vegetables, fruits, dried beef, dried fish and salt fishes. In yi dynasty, there are 62 kinds of table ware and cooking kitchen utensils, but many of them come to uselessness. 19 kinds of measuring unit are very non-scientific because that is not by weight but by bulk or volume. There are many food making terms which are 198 kinds of prepared cooking term, 11 kinds of cutting term and 20 kinds of boiling term. And 10 kinds of expression of taste can see this book.

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Influence of Yb2O3 Doping Amount on Screen-printed Barium Strontium Calcium Titanate Thick Films

  • Noh, Hyun-Ji;Lee, Sung-Gap;Ahn, Byeong-Lib;Lee, Ju
    • Transactions on Electrical and Electronic Materials
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    • v.8 no.6
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    • pp.241-245
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    • 2007
  • [ $(Ba_{0.9-x}Sr_xCa_{0.10})TiO_3$ ] (x=0.33, 0.36) powders were prepared by sol-gel method. $(Ba,Sr,Ca)TiO_3$(BSCT) thick films, undoped and doped with $MnCO_3$ and $Yb_2O_3(0.1{\sim}0.7mol%)$, were fabricated by the screen printing method on the alumina substrate. The coating and drying procedure was repeated 6-times. The Pt bottom electrode was screen printing method on the alumina substrate. These BSCT thick films were annealed at $1420^{\circ}C$ for 2 hr in atmosphere. The upper electrodes were fabricated by screen printing the Ag paste and then firing at $590^{\circ}C$ for 10 min. And then the structured and dielectric properties as a function of the doping amount of $Yb_2O_3$ were studied. As a result of the TG-DTA, exothermic peak was observed at around $670^{\circ}C$ due to the formation of the polycrystalline perovskite phase. All BSCT thick films showed XRD patterns of typical cubic peroveskite structure. The average thickness of BSCT thick films was about $70^{\mu}m$. The curie temperature and the dielectric constant decreased with increasing $Yb_2O_3$ doped content and the relative dielectric constant of the specimen, doped with 0.5 mol% $Yb_2O_3$ at BSCT(54/36/10), showed a best value of 5018 at curie temperature.

Properties of Starch Gels Mixed with Mugwort Juice (쑥즙을 첨가한 전분겔의 성질)

  • Chung, Koo-Min;Lee, Won-Jong
    • Korean Journal of Food Science and Technology
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    • v.29 no.4
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    • pp.693-699
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    • 1997
  • The effects of mugwort juice on the gel properties of corn starch (CS), mung bean starch (MS), and potato starch (PS) were investigated. Water holding capacities of three starches were increased with addition of the juice. Solubilities of CS and MS were also increased. Swelling power was increased in CS but decreased in MS. Viscoamylogram showed that 5% addition of the juice lowered the initial gelatinization temperatures of CS and MS, but raised the temperature of PS. While peak viscosities of CS and MS pastes were decreased a little, the viscosity of PS paste was decreased remarkably from 2,280 BU to 845 BU. Addition of mugwort juice did not affect significantly the hardness of starch gels during 7 days of storage at $25^{\circ}C\;and\;4^{\circ}C$. Degrees of gelatinization of the starch gels were affected by addition of the juice, especially in PS, during storage. Freeze-thaw stabilities of three gels were not changed by addition of the juice. The starch gels added with the mugwort juice had smooth surface visually because the crude fibrous materials of mugwort were removed during juice preparation.

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Plant RNA Virus Sequences Identified in Kimchi by Microbial Metatranscriptome Analysis

  • Kim, Dong Seon;Jung, Ji Young;Wang, Yao;Oh, Hye Ji;Choi, Dongjin;Jeon, Che Ok;Hahn, Yoonsoo
    • Journal of Microbiology and Biotechnology
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    • v.24 no.7
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    • pp.979-986
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    • 2014
  • Plant pathogenic RNA viruses are present in a variety of plant-based foods. When ingested by humans, these viruses can survive the passage through the digestive tract, and are frequently detected in human feces. Kimchi is a traditional fermented Korean food made from cabbage or vegetables, with a variety of other plant-based ingredients, including ground red pepper and garlic paste. We analyzed microbial metatranscriptome data from kimchi at five fermentation stages to identify plant RNA virus-derived sequences. We successfully identified a substantial amount of plant RNA virus sequences, especially during the early stages of fermentation: 23.47% and 16.45% of total clean reads on days 7 and 13, respectively. The most abundant plant RNA virus sequences were from pepper mild mottle virus, a major pathogen of red peppers; this constituted 95% of the total RNA virus sequences identified throughout the fermentation period. We observed distinct sequencing read-depth distributions for plant RNA virus genomes, possibly implying intrinsic and/or technical biases during the metatranscriptome generation procedure. We also identified RNA virus sequences in publicly available microbial metatranscriptome data sets. We propose that metatranscriptome data may serve as a valuable resource for RNA virus detection, and a systematic screening of the ingredients may help prevent the use of virus-infected low-quality materials for food production.

An Analytical Method for the Evaluation of Micro-cracking in Concrete Shrinkage Induced (콘크리트의 수축으로 인한 미세균열 발생 평가를 위한 해석적 기법)

  • Song, Young-Chul;Kim, Do-Gyeum;Moon, Jae-Heum
    • Journal of the Korea Concrete Institute
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    • v.22 no.1
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    • pp.69-76
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    • 2010
  • The majority of research that has been performed on cracking potential of concrete by shrinkage has assumed that concrete acts as a homogeneous material. However, with this approach, it is not able to evaluate the micro-cracking behavior in concrete due to autogenous shrinkage under unrestrained boundary condition (free boundary condition) nor to understand the cracking behavior properly because of the heterogeneous nature of concrete. To better understand the micro-cracking behavior of concrete induced by autogenous shrinkage, series of experiments were performed measuring the length change and acoustic emission energy. As an analytical approach, this research uses an object oriented finite element analysis code (OOF code) to simulate the behavior of the concrete on a meso-scale. The concrete images used in the simulations were directly obtained from mortar samples. From the experiments and simulation results, it was able to better understand the micro-cracking behaviour of concrete due to shrinking of paste phase and internal restraint by aggregates.

Incorporation of CrusHed Sands and Tunisian Desert Sands in the Composition of Self Compacting Concretes Part I: Study of Formulation

  • Rmili, Abdelhamid;Ouezdou, Mongi Ben;Added, Mhamed;Ghorbel, Elhem
    • International Journal of Concrete Structures and Materials
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    • v.3 no.1
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    • pp.3-9
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    • 2009
  • This paper examines the incorporation of the crushed sand (CS) and desert sand (DS) in the formation of self compacting concrete (SCC). These sands have been substituted for the rolled sand (RS), which is currently the only sand used in concretes and which is likely to run out in our country. DS, which comes from the Tunisian Sahara in the south, is characterized by a tight distribution of grains size. CS, a by-product of careers containing a significant amount of fines up to 15%, is characterized by a spread out granulometry having a maximum diameter of around 5mm. These two sands are considered as aggregates for the SCC. This first part of the study consists in analyzing the influence of the type of sand on the parameters of composition of the SCC. These sands consist of several combinations of 3 sands (DS, CS and RS). The method of formulation of the adopted SCC is based on the filling of the granular void by the paste. The CS substitution to the RS made it possible, for all the proportions, to decrease the granular voids, to increase the compactness of the mixture and to decrease the water and adding fillers proportioning. These results were also obtained for a moderate substitution of DS/CS (< 40%) and a weak ratio of DS/RS (20%). For higher proportions, the addition of DS to CS or RS did not improve the physical characteristics of the SCC granular mixture.

A Study on Seepage Cutoff Effect of the Environmentally Friendly SCM (SCM 친환경주입공법에 의한 차수 효과에 관한 연구)

  • Chun, Byung-Sik;Roh, Jong-Ryun;Jooi, Tae-Seong;Do, Jong-Nam
    • Journal of the Korean GEO-environmental Society
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    • v.6 no.4
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    • pp.65-71
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    • 2005
  • Recently, difficulties in soft ground improvement that caused by effectiveness of the ground improvement, the durability and environmentally friendliness of the injection material come to the fore. This paper studies the field applicability of the SCM in reinforcement and seepage cutoff of the back of an existing continuous wall. SCM uses double rod which imposes heavy pressure($10-100kgf/cm^2$) to disturbed, cut, discharge, and mix the ground. It is observed that a bulb is formed by using cement paste and environmentally friendly injection materials with minimal alkali leaching. Unconfined compression test and fish poison tests are performed. Test results indicate that the method results in higher durability, less leaching through use of the environmentally friendly injection material, and faster mobilization of the strength. In addition, field tests confirm the formation of the bulb and the seepage cutoff wall.

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