• Computers and Concrete
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• 제11권3호
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• pp.223-236
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• 2013

Self-healing (SH) technology of cracking is becoming a promising solution to improve the durability of cement based composites. However, little formula are available in the literature on determining the size and dosage of the self-healing capsules. Supposed that SH capsules will be broken and activated when they met cracks, a theoretical solution is developed to calculate the appropriate length of SH capsules based on Buffon's needle model. Afterwards, a method to calculate the dosage of capsules was proposed in terms of stereological theory. The reliability of the above mentioned theoretical methods was verified by computer simulation. An experiment of self-healing in mortar was performed as well, by which the theoretical models were verified.

• 한국연초학회지
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• 제18권2호
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• pp.126-131
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• 1996

In this study effects of isolation distance, transplanting time of maternal plants, and bagging of flower head with the gauze-cloth bag on the outcrossing of burley tobacco (Nicotiana tabacum L.) were investigated. Also the effect of fertilizer level and control of the number of capsules per plant on seed production and quality were examined. A male sterile line. produced 0.3 to 3.8 capsules Per plant when it was Planted with normally flowering tobacco with the average outcrossing of 7.2 plants, ranging from 2 to 18 out of 20 plants. With the farther the isolation distance between maternal plants and pollen donor plant, the lower the outcrossing occurred. Outcrossing occurred even at the isolation distance of 312 m. When the maternal plants were transplanted 35 days after transplanting the pollen donor ones, the outcrossed plants were not decreased significantly. The bagging of the flower head with the gauze-cloth bas (#0.9∼ 1.0 mm) decreased the outcrossed plants significantly, but couldn't prevent the outcrossing completely. The seed amount per plant was higher in the highly fertilized cultivation. The number of seed capsules per plant affected significantly on seed yield and quality. When the seed capsules was controlled by 30 or 50 capsules per plant, the weight of 1,000 seeds and germination rate were higher than those with 70 or 90 capsules per plant. Key words : Nicotiana tabacum, outcrossing, bagging.

• Smart Structures and Systems
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• 제25권3호
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• pp.337-343
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• 2020

In this paper, we focused on the self-healing concrete using new nano-capsules. Three types of nano-capsules with respect to availability, high strength and temperature tolerance are used; type 1 is URF and polyethylene (PE) as shell and nano titanium oxide (TiO₂) as core, type 2 is URF and PE as shell and nano silica oxide (SiO₂) as core, type 3 is PE as shell and nano silica oxide (SiO₂) as core. The concrete samples mixed by nano-capsules with three percents of 0.5, 1 and 1.5. Based on experimental tests and the compressive strength of samples, the URF-PE-SiO₂ is selected for additional tests of compressive strength before and after recovery, ultrasonic test, ion chlorine and water penetration depths. After careful investigation, it is concluded that the optimum value of URF-PE-SiO₂ nano-capsules is 0.5% since leads to higher compressive strength, ultrasonic test, ion chlorine and water penetration depths.

• 약학회지
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• 제55권5호
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• pp.411-418
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• 2011

The dissolution test method and an analytical procedure by HPLC were developed and validated for nafronyl oxalate capsules and tramadol hydrochloride capsules. These drugs were not yet characterized by the dissolution specifications in the Korean Pharmaceutical Codex. So, with each reference and test drugs, we did the preliminary and standard experiments based on the Korean Pharmacopeia Guideline of dissolution testing for solid oral dosage forms. The dissolution test for nafronyl oxalate capsules was carried out under sink conditions as follows: dissolution medium phosphate buffer pH 6.8, paddle rotation speed 100 rpm and vessel volume 900 ml. More than 80% of its label amount was released within 30 min in this method. Also the dissolution test for tramadol hydrochloride capsules was carried out under sink conditions as follows: dissolution medium water, paddle rotation speed 50 rpm and vessel volume 900 ml. More than 90% of its label amount was released within 15 min in this method. The dissolution samples were analyzed with a validated HPLC analytical procedure. The analytical methodology showed acceptable values in terms of specificity, linearity, precision and accuracy. The dissolution test methods described above were adequate for the purpose and may be proposed as a pharmacopeial standard to assess the performance of nafronyl oxalate capsules and tramadol hydrochloride capsules. Furthermore, the outcomes of this study were expected to help create an environment where safe and high quality drugs would be distributed on the domestic market making contributions to advancing public health.

• Asian Pacific Journal of Cancer Prevention
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• 제17권8호
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• pp.4125-4129
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• 2016

Background: Chemotherapy-induced nausea and vomiting (CINV) places a significant burden on the patient. Herbal agents are the most commonly complementary therapies used among the public. This study was done to determine the effect of ginger and chamomile capsules on nausea and vomiting in cases undergoing chemotherapy for breast cancer (BC). Materials and Methods: In a randomized, double-blind and clinical trial study, 65 women with BC undergoing chemotherapy were referred to Breast Cancer Research Center, Tehran, Iran, between May 2013 to June 2014. Regimen for ginger group for 5 days before and 5 days after chemotherapy was: 2 times a day and 500 mg capsules of powdered ginger root in addition to a routine antiemetic regimen consisting of dexamethasone, metoclopramide and aprepitant (DMA) capsules. Chamomile group similarly was: 2 times a day and 500 mg capsules of Matricaria chamomilla extract in addition to a routine antiemetic regimen consisting of DMA capsules. Control group, routine antiemetic regimen consisting of DMA capsules. Results: There were no significant differences between the ginger, chamomile and control groups regarding age. Drugs used for chemotherapy were identical and duration of disease was also matched (1-4 months). Ginger and chamomile were both significantly effective for reducing the frequency of vomiting, there being no significant difference between the ginger and chamomile groups. Moreover, unlike the chamomile, ginger significantly influenced the frequency of nausea. Conclusions: According to the findings of this study, it should be declared that taking ginger capsules (1 g/day) might relieve CINV safely. Nurses dealing directly with cancer patients should be responsible for providing educational programs for patients and their families about how to deal with their drug regimens and associated side effects.

• 한국건설순환자원학회논문집
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• 제9권3호
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• pp.397-404
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• 2021

본 연구에서는 고상캡슐을 활용한 자기치유 표면보호재를 보수재료로 활용하기 위한 일환의 연구로써 고상캡슐이 표면보호재의 품질에 미치는 영향 및 장기재령의 치유 특성을 검토하였다. 고상캡슐 혼합에 따른 자기치유 표면보호재의 유변학적 특성 평가결과, 소성점도 및 항복응력, 테이블 플로우는 감소하는 경향이 나타났으며, 압축강도의 경우 고상캡슐 1%당 1 MPa이 비례적으로 감소하였다. 장기재령 치유특성을 평가한 결과, 재령 91일이 경과된 경우에도 고상캡슐이 보존되어 10% 혼합한 경우 치유재령 28일에 90% 수준의 치유율이 나타났으며, 치유재령 91일 경과후에는 고상캡슐 5%의 경우에도 90% 수준의 치유율이 나타났다.

• Advances in aircraft and spacecraft science
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• 제4권4호
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• pp.487-501
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• 2017

The main purpose of the paper is to analyze effect of geometrical parameters of the reentry capsules such as radius of the spherical cap, shoulder radius, back shell inclination angle and overall length on the flow field characteristics. The numerical simulation with viscous flow past ARD (Atmospheric Reentry Demonstrator), Soyuz (Russian) and OREX (Orbital Reentry EXperimental) reentry capsules for freestream Mach numbers range of 2.0-5.0 is carried out by solving time-dependent, axisymmetric, compressible laminar Navier-Stokes equations. These reentry capsules appear as bell, head light and saucer in shape. The flow field features around the reentry capsules such as bow shock wave, sonic line, expansion fan and recirculating flow region are well captured by the present numerical simulations. A low pressure is observed immediately downstream of the base region of the capsule which can be attributed to fill-up in the growing space between the shock wave and the reentry module. The back shell angle and the radius of the shoulder over the capsule are having a significant effect on the wall pressure distribution. The effects of geometrical parameters of the reentry capsules will useful input for the calculation of ballistic coefficient of the reentry module.

• 대한기계학회논문집
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• 제19권10호
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• pp.2647-2656
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• 1995

The present work was performed to axially and radially investigate the local cold storage performance in the cylindrical tank with the spherical capsules inserted n-Tetradecane as a new cold storage material. The local cold storage performance of the capsules in the tank was experimentally investigated for the inlet temperature of -7, -5, -3, 0.deg. C, for the flow rate of 0.95, 1.89, 2.84, 6.00 l/min, and for the diameter ratio of 4.9, 9.0, 13.1. The local cold storage performance in the case of using water applied for the commercial ice-ball system was axially investigated by changing the flow rate only with the inlet temperature of -7.deg. C and the diameter ratio of 9.0 in order to compare with the performance in the case of using n-Tetradecane. For the case of using n-Tetradecane, the difference of cold storage period between the first and the seventh story was increased as the inlet temperature was increased and the flow rate was decreased. The capsules at the center of the tank showed the supercooling and the increased cold storage period compared with the capsules at the wall of the tank due to the small porosity and insufficient cold storage performance at the center of the tank as the diameter ratio is increased. The case using water showed worse cold storage performance due to comparatively large supercooling than the case using n-Tetradecane.

• 대한약리학회지
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• 제13권1호
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• pp.1-6
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• 1977

The physicochemical equivalencies of drugs are not usually correlate to the generic equivalencies of drugs and the generic equivalencies of drugs produced by different manufacturers or different formulations are being called in question frequently. The bioabailability of two formulations of oxytetracycline and erythromycin stearate were performed in healthy human volunteers. At the same time, the disintegration testes were performed with randomly sampled materials in question. For the biological evaluation of new oxytetracycline formulation; tablet(250mg), two-way cross over study in 10 healthy young volunteers was performed using oxytetracycline capsule (250mg) as reference, Erythromycin stearate (250mg) tablets and capsules produced by different manufacturers were compared in a two-way cross over study in 12 subjects with same manner of oxytetracyclines. oxytetracycline tablets showed somewhat slow disintegration rate, but appeared not statistical differences in serum concentrations from the reference, up to six hours after ingestion. Erythromycin stearate capsules disintegrated more rapidly than enteric coated tablets. Serum concentrations of capsules were more variable and markedly lower (P<.005 after 2hrs) than the enteric coated tablets. Rapid disintegration of capsules may result in destruction of active chemicals owing to the interaction with gastric acid and the above factor may contribute mainly to the low serum level after ingestion of capsules.

• 한국태양에너지학회 논문집
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• 제39권5호
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• pp.65-78
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• 2019

In this study, we investigated the paraffin encapsulation using double-walled encapsulation technique. The first encapsulation used methyl methacrylic acid as the main component in acrylic polymer and the second encapsulation used melamine polymer. Particles size and distribution of the capsules were analyzed using scanning electron microscopy. In the first encapsulation, the stable capsules were obtained at 67% of phase change material ratio to methyl methacrylic acid monomer and the size of the capsule was from 0.2 to $0.3{\mu}m$. In the second encapsulation, the size of the capsules was almost the same with those capsules prepared in the first encapsulation. The particle size of single wall and double wall was about $0.3{\mu}m$. As a result of the encapsulation of paraffin using double-walled encapsulation technique, it was confirmed that the particle size was determined in the process of encapsulating using the acrylic polymer at the first wall material, and the physical and thermal stability of the capsules were imparted using melamine at the secondary wall material.