• Title/Summary/Keyword: Filling rate

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Valorization of marble's waste as a substitute in sand concrete

  • Ouassila, Boughamsa;Houria, Hebhoube;Leila, Kherref;Mouloud, Belachia;Assia, Abdelouahed;Chaher, Rihia
    • Advances in concrete construction
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    • v.9 no.2
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    • pp.217-225
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    • 2020
  • The recovery of waste proves a solution with two impacts: the environmental impact by the reduction of pollution and the gain of the occupied space by this waste, and the economic impact by the use of these lasts in the building and in the area of public works. The present research consists in recovering a waste marble (thrown powder exposed to the different meteorological phenomena) generated by the quarry marble of Fil-fila, located at the east side of Skikda in the north-east of Algeria, and add it, as sand in the composition of sand concrete. To carry out this research, we analyzed the evolution brought by the substitution of ordinary sand by marble waste sand, with 25%, 50%, 75% and 100% on the properties in the fresh state (density, workability and air content) and in the cured state (compressive strength, tensile strength, surface hardness and sound velocity). For durability we tested water absorption by immersion and chloride penetration. The results obtained are compared with control samples of 0% of substitution rate. In order to have a good filling of the voids in the granular skeleton; we added a quantity of limestone recycled fines from the quarries and for a good workability a super-plasticizing additive. The results showed that the partial substitution modified both the fresh and the hardened characteristics of the tested concretes, the durability parameters also improved.

Overexpression of OsNAC17 enhances drought tolerance in rice

  • Kim, Tae Hwan;Kim, Ju-Kon
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.168-168
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    • 2017
  • Drought conditions during cultivation reduce agricultural production yield less than a theoretical maximum yield under normal condition. Plant specific NAC transcription factors in rice are known to play an essential roles in stress resistance transcriptional regulation. In this study, we report the rice (Oryza sativa L japonica) NAM, AFTF and CUC transcription factor OsNAC17, which is predominantly induced by abiotic stress in leaf, was contribute to the drought tolerance mediated reactive oxygen species (ROS) in transgenic rice plants. Constitutive (PGD1) promoter was introduced to overexpress OsNAC17 and produced the transgenic PDG1:OsNAC17. Overexpression of OsNAC17 throughout the whole plant improved drought resistance phenotype at the vegetative stage. Morphological characteristics such as grain yield, grain filling rate, and total grain weight improved by 22~64% over wild type plants under drought conditions during the reproductive stage. The improved drought tolerance in transgenic rice was involved in reducing stomatal density up to 15% than in wild type plants and in increasing reactive oxygen species-scavenging enzyme. DEG profiling experiment identified 119 up-regulated genes by more than twofold (P<0.01). These genes included UDP-glycosyltransferase family protein, similar to 2-alkenal reductase (NADPH-dependent oxireductase), similar to retinol dehydrogenase 12, Lipoxygenase, and NB-ARC domain containing protein related in cell death. Furthermore, OsNAC17 was act as a transcriptional activator, which has an activation domain in C-terminal region. These result demonstrate that the overexpression of OsNAC17 improve drought tolerance by regulating ROS scavenging enzymes and by reducing stomatal density

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Comparison of Two Vitrification Methods of In Vitro Development Oocytes Collected from Porcine Antral Follicles Using Open Pulled Straw (OPS) Techniques

  • An, Mihyun;Hong, Daewuk;Son, Dongsoo;Seok, Hobong
    • Proceedings of the Korean Society of Embryo Transfer Conference
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    • 2002.11a
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    • pp.84-84
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    • 2002
  • The advantages of the OPS techniques(Vajta G et al, Mol Reprod Dev 51: 53-58,1998) give 1) high survival rates of various types of eggs, 2) quick and simple process, 3) inexpensive equipment and reduced chilling injury. The efficiency of IVM/IVF technique in the porcine species is relatively lower than that obtained in other species such as ruminants. Two experiments were designed to investigate the effects of in-vitro fertilization of porcine oocytes matures using different OPS protocol for chilling and warming of vitrification. Porcine oocytes from ovaries collected at abattoir were matured for 44 hours in TCM199 Earle's salt supplemental with pyruvate, pff, L-cysteine, hormones and gentamycin. Oocytes were denuded and fertilized with frozen boar semen by common method. Porcine embryos produced routinely by in-vitro culture system of NCSU23 medium. The vitrification and the warming were conducted by OPS method with the glass micropipette instead of straw vessels and modified the protocol of G.Vajta(1999). In Exp 1, Chilling/Warming:Holding Medium(HM)+EG+DMSO/HM +sucrose Medium(SM) at 39$^{\circ}C$ warm stage. In Exp 2, : PBS+CS+EG+Ficoll+ Trehalose/PBS+Trehalose at 25$^{\circ}C$ stage. Filling, freezing, packing, thawing out and further culturing were performed to follow the basic protocol of G Vajta. During IVM-lVC and post-warming, fertilization parameter and developmental potential were compared to and statistically analysed. It was not significantly different from Exp 1 and Exp 2 but 25$^{\circ}C$ of stage was slightly higher on the morula/blastocyst forming rate and better atmosphere for worker than that at 39$^{\circ}C$ stage.

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Development of a Low-cost and High-efficiency Post-harvest Bulk Handling Machinery System of Onion - Performance Evaluation and Control

  • Park, Jongmin;Kim, Jongsoon;Jung, Hyunmo
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.26 no.2
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    • pp.61-69
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    • 2020
  • As post-harvest processes of onions are carried by a 20 kg-net package which results in high-cost and low-efficiency, especially, the insufficient drying and physical damage of onions after harvesting leads to a huge second loss in storage, we had developed a low-cost, high-efficiency post-harvest bulk handling machinery system by collecting onions on a farm using ton-bags, drying with forced air circulation, and sorting/packaging. The post-harvest bulk handling machinery system consisted of 6 devices, and this study designed an automatic feed hopper with a feeding rate control device, an inclined belt conveyor with a two-step chute, and an automatic pallet unloading device for feeding onions into the sorting/packing line. This study also analyzed the performance and control of the total system. The device had 1-ton handling capacity, but the operational condition was set to increase the capacity. The three-step filling method of pallet by the velocity control of the inclined belt conveyor was applied in the post-harvest bulk handling machinery system for the prevention of physical damage. If one worker was set to operate the total system, the time required to complete one palletized load was approximately 5 minutes and 5 seconds. The calculated daily handling capacity was approximately 94 tons, when the daily actual working time was 8 hours. When the developed system was applied to the managerial size of 2,000 ton, the processing cost per ton of the system was decreased by 19.5%, compared with the existing 20 kg-net package-based handling. The developed post-harvest bulk handling machinery system would be a good substitute for the rapid decline and aging of rural labor.

Evaluation of Pharmacy Students' Perception on Clinical Pharmacy Practice Experience in the Tertiary and Secondary Hospital settings (상급종합병원과 종합병원 필수실무실습에 관한 학생들의 인식 평가)

  • Chun, Pusoon;Sin, Hye Yeon
    • Korean Journal of Clinical Pharmacy
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    • v.28 no.1
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    • pp.30-39
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    • 2018
  • Background: Clinical Pharmacy Practice Experience (CPPE) is an important curriculum that offers students patient-centered disease prevention and treatment with evidence-based optimal pharmacotherapy for better clinical outcomes. However, few studies have evaluated the perception of pharmacy students regarding CPPE in tertiary and secondary hospitals. This study aimed to evaluate the perception of pharmacy students regarding the learning program of CPPE. Methods: The survey questionnaire consisted of 15 self-administered questions regarding pharmacy practices, barriers, and improvement of practical training. Fourteen institutional pharmacies located in seven regions responded to a survey questionnaire from March 1 to June 30, 2017. The participants were pharmacy students doing clerkship in a hospital setting. Results: The response rate was 73.6%. Thirty-five participants (22.4%) had used a hospital library, but 121 (77.6%) had never used the library for drug information resources. Eighty-one (50.0%) responded that clinical knowledge and drug information was the most beneficial practice. Thirty-seven (31.1%) respondents in the tertiary hospitals and 19 (46.3%) in the secondary hospitals answered that they were filling prescriptions during the daily break. On the other hand, 72 respondents (60.5%) in the tertiary hospitals and 17 (41.5%) in the secondary hospitals did literature research to prepare for presentation. Conclusion: More students in secondary hospitals continue to fill prescriptions during the daily break, as compared to those in tertiary hospitals. Therefore, the authors suggest self-directed learning to improve clinical performance and each institution considers offering onsite or online library service to improve evidence-based CPPE for pharmacy school students.

THE EFFECT OF THE TRICALCIUM PHOSPHATE AND VITAPEX ON THE DOGS' PERIAPICAL TISSUES (Tricalcium phosphate와 Vitapex가 치근단 조직에 미치는 영향에 관한 실험적 연구)

  • Choi, Gi-Won
    • Restorative Dentistry and Endodontics
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    • v.14 no.1
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    • pp.71-84
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    • 1989
  • The purpose of this study was to evaluate the effect of tricalcium phosphate and Vitapex on the dogs' periapical tissues. Twenty mandibular premolars from 5 healthy dogs were used for this study. After the animals were anesthetized intramuscularly, pulp chambers were open and pulp tissue was extirpated with a barbed broach and H-file. Then the working length of the root canal was measured with H-file and pulp tissue was completely removed. Before the actual canal filling, the root canals of twenty teeth have been experimentally infected with opening the pulp chamber for 5 weeks. Periapical radiographs of the experimental teeth were taken to monitor the periapical pathological condition. Each root apex of 20 premolars was perforated with engine reamer and the root canals were enlarged with No. 30-60 H-files. They were divided into treated as follows. Control group: The root canal was filled with gutta-percha. Experimental group 1: The canal was dried with sterile paper points and mixture of tricalcium phosphate and physiological saline was overfilled beyond the root apex with a lentulo spiral. Then the root canal was filled gutta-percha and lateral condensation and the pulp chamber was filled with Caviton. Experimental group 2: The root canals were overfilled with Vitapex and were treated in the same manner as those in experimental group 1 At 1,2,3, and 8 weeks after experiment, the periapical tissues including the alveolar bone were fixed with 10% formalin solution for I week and decalcified with Plank-Rycho solution for 5 weeks. The specimens were embedded in paraffin and serial sections were cut into a thickness of 6 ${\mu}m$ at the plane of the root apex. Hematoxyline-eosin and Masson's trichrome stain were made for the histo-pathological examinations. The results were as follows: 1. Ingrowth of collagen fiber was observed from 1 week in control group and experimental groups. 2. The rate of bone formation of experimental group 1 was accelerated more than that of experimental group 2. 3. Resorption of cementum was seen in control group, but apposition of cementum was seen in experimental groups.

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Changes of Seed Moisture Content and Quality during Grain-filling in Early Maturing Soybean Genotypes (올콩의 등숙단계별 종실 수분함량 및 품질 변화)

  • 박금룡;류용환;최경진;김석동
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.39 no.5
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    • pp.420-425
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    • 1994
  • Soybean seeds deteriorate even before harvest, especially under high temperature and high relative humidity conditions. This study was conducted to determine the effect of harvest date on seed quality in early maturing soybean cultivars. Soybean cultivars used in the experiment were Damyang-native, having small seed with yellow color, and Yuhsuzumi, having large seed with green color. The length of physiological maturity to grain harvest was 24 days in Yuhsuzumi and 8 days in Damyang-native. The moisture contents of seed were 25.3 % in Yuhsuzumi and 14.5 % in Damyang-native cultivar when pod reached its mature pod color. The seed color of Yuhsuzumi started to turn yellow, and its germination rate was greatly decreased when harvest was delayed after maturity, However, Damyang-native cultivars produced seed of high quality regardless of delayed harvest.

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A Study on the Physical Properties and Subjective Evaluation of the PTT[Poly(trimethylene terephthalate)] Fabric (PTT[Poly(trimethylene terephthalate)] 직물(織物)의 물리적(物理的) 특성(特性)및 주관적(主觀的) 평가(評價)에 관(關)한 연구(硏究))

  • Seo, Hyo-Jeong;Kim, Jong-Jun;Jeon, Dong-Won
    • Journal of Fashion Business
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    • v.7 no.4
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    • pp.121-128
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    • 2003
  • A new textile material, poly(trimethylene terephthalate) polymer, has been introduced to the textile industry. The structure of PTT is similar to the PET, while the tensile deformation and subsequent recovery property is better than that of PET. In this study, the physical and mechanical properties of textile woven fabrics made of PTT, PET, and nylon 6 yarns as the filling yarn were determined using the Kawabata Evaluation System (KES), including tensile, bending, shearing, compression, and surface related parameters. On top of these measurements, the subjective ratings by evaluators were performed on the fabric samples. From the examination of the stress-strain behavior of the yarn specimens focused on the recovery mode, it was evident that the PTT specimen developed lower stress at 3% elongation. The subsequent recovery curve showed that the PTT has less stress-decay rate than the other specimens, implying that the recovery behavior of the PTT is recommendable for the end-uses including stretchable textile materials, sports wears, etc. The KES bending rigidity(B) value of the PTT sample fabric was lower than that of the PET sample fabric. Subjective evaluation of the fabric samples by the evaluators on the descriptive word pair "soft - not soft" showed similar tendency with the KES B determination of the fabric samples.

Basic Study on the Regenerator of Stilting Engine (II) - Heat transfer and flow friction loss characteristics of the regenerator with wire screen matrix - (스털링기관용 재생기에 관한 기초연구 (II) - 철망을 축열재로 한 재생기의 전열 및 유동손실특성 -)

  • 김태한;이시민;이정택
    • Journal of Biosystems Engineering
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    • v.27 no.6
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    • pp.529-536
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    • 2002
  • The performance of stilting engine, in particular, its energy conversion efficiencies are critically influenced by the regenerator characteristics. The regenerator characteristics are influenced by effectiveness, void fraction. heat transfer loss and fluid friction loss in the regenerator matrix. These factors were influenced by the surface geometry and material properties of the regenerator matrix. The regenerator design goals arc good heat transfer and low pressure drop of working Bas across the regenerator. Various data for designing a wire screen matrix have been given by Kays and London(1984). The mesh number of their experiment. however, was confined below the No. 60. which seems rather small for the Stirling engine applications. In this paper. in order to provide a basic data for the design of regenerator matrix, characteristics of heat transfer and flow friction loss were investigated by a packed mettled of matrix in oscillating flow as the same condition of operation in a Stirling engine. Seven kinds of sing1e wire screen meshes were used as the regenerator matrices. The results are summarized as follows; 1. While the working fluid flew slowly in the regenerator. the temperature difference was great at the both hot-blow(the working fluid flows from healer to cooler) and cold-blow(the working fluid flows from cooler to healer). On the other hand. while the working fluid flew fast. the temperature difference was not distinguished. 2. The No.150 wire screen used as the regenerator matrix showed excellent performance than tile others. 3. Phase angle variation and filling rate affected heat transfer or regenerator matrices. 4. Temperature difference between the inlet and outlet of the regenerator is very hish in degree of 120 phase angle.

Relationship between Seed Vigour and Electrolyte Leakage in Rice Seeds with Different Grain-filling Period

  • Kim, Jin-Ho;Lee, Sheong-Chun;Song, Dong-Seog
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.43 no.3
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    • pp.147-151
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    • 1998
  • The conductivity test is a measure of electrolytes leakage from plant tissue. The shorter the maturation period after heading was the greater electrical conductivity (EC) of rice seed. The polymer-coated seed was not different in EC compared with non-coated seed. As soaking time of rice seed increased, EC increased gradually. The EC varied from 9.9 to 20.7$\mu$S $cm^{-1}g^{-l}$ for control plots and from 21.3 to 41.7$\mu$S $cm^{-1}g^{-l}$ for heat-killed seeds which were produced by autoclaving seeds at 121$^{\circ}C$ for 20 minutes. The germination speed (the rate of 5th day) of rice seed was 94% at control plot, 83% at low temperature and 20% at high temperature. Besides, germination percentage was 95% for the control, 92% for the low temperature treatment and 39% for the high temperature treatment. The EC was negatively correlated (r=-0.771$^{**}$) with germination percentage at low temperature. Water uptake in seeds of 30, 40, 50 days after heading (DAH) was greater than that of 20 DAH. Plant height of seedlings was 9.84 cm for the control but 4.32 cm for the high temperature treatment, and the tallest for polymer-coated seed. Dry weight of seedlings was 0.841 g for the control and 0.287 g at high temperature. Besides, the polymer-coated seed was heavier than non-coated seed. The number of roots was largest from 40 to 50 DAH and polymer-coated seed, but was decreased from 20 to 30 DAH. The length of roots was 20.52 cm at control plot and 19.89 cm polymer-coated seed but 8.68 cm for the low temperature treatment and 7.28 cm for the high temperature treatment.

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