• 제목/요약/키워드: PVS

검색결과 127건 처리시간 0.025초

실리콘폴리머의 혼합사용이 폴리비닐실록산 치과용 인상재의 물성에 미치는 영향 (Effects of Silicone Polymer Blends on Physical Properties of Dental Polyvinylsiloxane Impression Materials)

  • 임창하;김민강;김영철;박남국;송호준;박영준
    • Elastomers and Composites
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    • 제44권1호
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    • pp.76-83
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    • 2009
  • 본 연구는 비닐작용기의 위치가 다른 실리콘 프리폴리머와 수소작용기의 위치가 다른 가교제, 그리고 이들의 혼합사용이 제조된 치과용 폴리비닐실록산 고무인상재의 물성에 미치는 영향을 연구하였다. 한 종류의 중점도 프리폴리머를 사용한 실험군은 인장강도, 파단신율, 압축시 변형률이 다른 특성의 프리폴리머들을 혼합사용한 경우보다 낮은 값을 보였다. 측부와 말단에 수소작용기가 있는 CR210 가교제를 사용한 실험군은 측부에만 수소작용기가 있는 CR101 가교제를 사용한 실험군에 비해 압축시 변형률과 파단신율이 더 높았다. 측쇄에도 비닐기를 갖는 높은 비닐함량의 프리폴리머를 사용한 경우는 더 높은 인장강도를 보였지만, 경화 속도가 늦어서 임상 사용에 적합한 작업성을 갖는 치과용 인상재를 만들기 위해서는 이 성분이 경화시간에 미치는 영향과 이를 조절할 수 있는 방안에 대한 지속적인 연구가 필요하다고 생각한다.

작은방울-유리화법에 의한 국화 신초의 초저온동결보존 (Cryopreservation of chrysanthemum shoot tips using the droplet-vitrification technique)

  • 이윤걸;박상언;김행훈
    • 농업과학연구
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    • 제38권2호
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    • pp.227-233
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    • 2011
  • This study aimed at developing cryopreservation protocol for chrysanthemum (Dendranthema grandiflora Tzelevcv. peak) shoot apices based on droplet-vitrification procedure, which is a combination of droplet-freezing and solution based vitrification. Progressive preculture of shoot apices in liquid MS medium supplemented with 0.3 and 0.7 M sucrose for 31 and 17 hours, respectively, was found optimum among preculture treatments tested. The composition of both loading and vitrification solutions significantly affected recovery growth of shoot tips before and after cryopreservation. Balancing glycerol and sucrose concentrations in the solutions was beneficial for recovery growth. The highest recovery after cryopreservation was observed when apical shoot tips were extracted from 4-week-old in vitro plantlets, progressively precultured with 0.3-0.5-0.7 M sucrose for 32-16-6 hours, respectively, then treated with loading solution comprising of 1.9 M glycerol + 0.5 M sucrose (35% PVS3 solution). Apices were then dehydrated with the vitrification solution consisted of 50% glycerol + 50% sucrose for 90 minutes then directly immersed in liquid nitrogen.

발파진동 예측방법에 관한 연구 (A Study on the Prediction Method of Blasting Vibration)

  • 이연수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 추계학술대회논문집
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    • pp.361-365
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    • 2006
  • In order to predict method of blasting vibration in ground and it's resident located around blasting field in urban area, blasting vibration characteristics were measured the vibration velocity(cm/sec), vibration acceleration($cm/sec^2$), vibration acceleration level(dB) and vibration level(dB(V)). The charged powder were used to 1.25kg and measuring sites were 25 points front 4m to 90m at the ground. The correlation of vibration velocity, vibration acceleration, vibration acceleration level and vibration level by square root scaled distance and cube root scaled distance were investigated. The correlation of PPV(peak particle velocity) velocity by SRSD(square root scaled distance) and CRSD(cube root scaled distance) was 0.85 and 0.86 and the correlation of PVS(peak vector sum) velocity by SRSD and CRSD was 0.82. Also vibration acceleration, vibration acceleration level and vibration level by SRSD and CRSD was 0.61, 0.62 and 0.82, respectively. As results, the vibration velocity and vibration level(dB(V)) was showed good correlation, but the vibration acceleration and vibration acceleration level was not showed good correlation.

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Educational Intervention on Breast Cancer Early Detection: Effectiveness among Target Group Women in the District of Gampaha, Sri Lanka

  • Vithana, PVS Chiranthika;Ariyaratne, MAY;Jayawardana, PL
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권6호
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    • pp.2547-2553
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    • 2015
  • Purpose: The present study concerns the effectiveness of an educational intervention for improving knowledge, attitudes and practices (KAP) of breast cancer early detection among target group women (TGW) in the district of Gampaha, Sri Lanka. Materials and Methods: The study was a community-based intervention. Two medical officer of health areas in Gampaha district were selected using random sampling as intervention (IA) and control (CA). Public health midwives (PHMs) in the IA were exposed to the educational intervention first, conducted the same among the TGW through PHMs. KAP was assessed using an interviewer- administrated questionnaire among 260 TGW from each area selected using cluster sampling before and six months after the intervention. Results: The overall median scores for KAP among TGW in IG increased significantly from pre intervention level of 54% (IQR: 46-59%), 50% (IQR: 41-59%), and 0% (IQR: 0-20%) to post intervention level of 77% (IQR: 72-82%), 68% (IQR: 59- 76 %) and 40% (IQR: 20-60%) respectively. In CG, overall median scores for KAP remained almost the same at pre intervention 54% (IQR:44-59%), 50% (IQR:36-59%) and 0% (IQR: 0-20%) and post intervention 54% (IQR:46-59%), 50% (IQR:36-64%) and 0% (IQR: 0-20%) respectively. Conclusions: The educational intervention was found to be effective.

Compensation for Photovoltaic Generation Fluctuation by Use of Pump System with Consideration for Water Demand

  • Imanaka, Masaki;Sasamoto, Hideki;Baba, Jumpei;Higa, Naoto;Shimabuku, Masanori;Kamizato, Ryota
    • Journal of Electrical Engineering and Technology
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    • 제10권3호
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    • pp.1304-1310
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    • 2015
  • In remote islands, due to expense of existing generation systems, installation of photovoltaic cells (PVs) and wind turbines has a chance of reducing generation costs. However, in island power systems, even short-term power fluctuations change the frequency of grids because of their small inertia constant. In order to compensate power fluctuations, the authors proposed the power consumption control of pumps which send water to tanks. The power control doesn’t affect water users’ convenience as long as tanks hold water. Based on experimental characteristics of a pump system, this paper shows methods to determine reference power consumption of the system with compensation for short-term PV fluctuations while satisfying water demand. One method uses a PI controller and the other method calculates reference power consumption from water flow reference. Simulations with a PV and a pump system are carried out to find optimum parameters and to compare the methods. Results show that both PI control method and water flow calculation method are useful for satisfying the water demand constraint. The water demand constraint has a little impact to suppression of the short-term power fluctuation in this condition.

방위각과 초친수코팅에 따른 태양광발전량 시뮬레이션과 하수처리장 에너지자립율 산정 (Estimation of energy self-sufficiency in municipal wastewater treatment plant using photovoltaic power simulated by azimuth and hydrophilic coating)

  • 안영섭;김성태;강지훈;채규정;윤종호
    • KIEAE Journal
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    • 제11권6호
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    • pp.133-138
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    • 2011
  • This paper presents energy self-sufficiency simulated in municipal wastewater treatment plants (WWTPs) by adopting solar energy production systems that were simulated by varying azimuth and super-hydrophilic coating on the surface of photovoltaic (PV). Relative to the national average energy consumption in WWTPs, the employment of 100 kW PV system was simulated to achieve 2.75% of energy self-sufficiency. The simulated results suggested that the installation of PVs toward South or Southwest would produce the highest energy self-sufficiency in WWTPs. When super-hydrophilic coating was employed in the conventional PV, 5% of additional solar energy production was achievable as compared to uncoated conventional PV. When 100 kW of PV system was installed in a future test-bed site, Kihyeung Respia WWTP located in Yongin, South Korea, the energy self-sufficiency by solar power was simulated to be 1.77%. The simulated solar power production by azimuth and super-hydrophilic coating will be useful reference for practitioners in designing the solar PV systems in the WWTPs.

A primo vessel-like structure in a dog with inflammatory pseudotumor

  • Cho, Sung-Jin;Hong, Sun-Hwa;Han, Sang-Jun;Kim, Ok-Jin
    • 한국동물위생학회지
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    • 제35권1호
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    • pp.77-82
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    • 2012
  • Inflammatory pseudotumor (IPT) is a term defining a mass characterized microscopically by a proliferation of bland mesenchymal spindle cells infiltrated by diffuse mixed inflammatory cells with a predominance of plasma cells and lymphocytes. Here, we show the primo vessel-like structure of the primo-vascular system (PVS) in a dog with IPT. A 6-years old male Mongrel dog was diagnosed with an abnormal mass (diameter 5.5 cm, weight 22 g) near left preputial area. The dog was submitted to the surgical detectomy of the mass. During the surgical operation, we observed primo vessel-like material. After fixations, the masses appeared macroscopically as lipoid-like, firm, white to grey masses, measuring $5{\times}8cm$. Histologically, cellular infiltration into the muscular layers was frequently seen. The mesenchymal proliferation remained the main component of the mass and was composed of myofibroblastic-like spindle cells characterized by globular, irregular nuclei containing open chromatin and a prominent nucleolus. On the basis of the histopathologic lesions, the subcutaneous mass was diagnosed as IPT. Also, we detected a primo vessel-like structures in some areas of the IPT tissues. These were observed as novel thread-like structures and bundle of tubular structures. To our knowledge, this report is the first case of primo vessel-like structure in a dog with IPT.

감자 바이러스 S의 순화와 항혈청제조 (Purification and Serology of Potato Virus S)

  • 이순형;이기운;정봉조
    • 한국응용곤충학회지
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    • 제16권3호
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    • pp.145-148
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    • 1977
  • 감자바이러스 S(PVS)의 진단, 동정 및 씨감자의 검정에 이용할 항혈청을 만들기 위하여 이병주로부터 PVS를 순수분리 순화하여 항혈청을 제조하였다. PVS는 지표식물파 전자 현미경으로 순수 분리하여 Nicotiana debneyii에서 증식하여 순화하였다. 순화된 PVS의 순화도는 1.18mg/ml이었으며 이것을 1.5ml씩 7일 간격으로 5회 .토끼에 주사하였으며 마지막 주사후 10일에 채혈하여 항혈청을 분리하였다. 제조된 PVS항혈청의 역가는 미량침강법에 의하여 1/2048로 나타났다.

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초고층빌딩의 BIPV 적용성 검토를 위한 선진 사례 조사 (The Advanced Case Study for Investigation on Application of BIPV on Tall Building)

  • 이종민;석호태;양정훈
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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    • pp.155-160
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    • 2009
  • The increasingly high prices for oil, the exhaustion of fossil fuels as well as concern about global warming are driving rapid growth of alternative sources of energy in the world. The active solution for global environment and exhaustion of energy sources is to develop and popularize the technologies to use natural energy such as sunlight, wind, and water. PV(Photovoltaic) modules are efficient devices that has been considered a logical material for use in buildings. Recent advanced BIPV(Building Integrated PV) technology have rapidly made PVs suitable for direct integration into construction in the world. Recently, building has been higher and higher. Tall buildings have many advantages for BIPV such as wide facade area and no shading effect by the surrounding buildings. However. BIPV has not been applied for tall building facade yet. Therefore, the purpose of the research is to develop suitable BIPV for tall buildings and to put these technologies to practical use. Therefore, the purpose of the study is to investigate unification of BIPV to curtain wall to apply BIPV on tall building through research into advanced application of overseas BIPV cases.

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Artificial Photosynthesis Using Zeolites

  • Castagnola, Norma B.;Dutta, Prabir K.
    • Journal of Photoscience
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    • 제6권3호
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    • pp.91-96
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    • 1999
  • Zeolites and microporouos materials continue to attract attention as novel hosts for photochemical reactions. Zeolities are attractive because of their ability to selectivity exchange and incorporate species within the void spaces and interconnecting channels, providing a spatial arrangement of molecules. Our research has primarily focused on intrazeolitic electron transfer from excited Ru(bpy)32+ in supercages of zeolite Y to a series of bipyridinium ions. In the Ru(bpy)32+ viologen-zeolite Y samples, the slowing of the back electron transfer from the bipyridinium radical cation to Ru(bpy)32+ allows for charge propagation via self exchange between diquat molecules. This provides an opportunity for permanent charge separation. When the migrating charge on the diquat radical within the zeolite reaches the surface, it can be transferred to a neutral viologen (PVS) in solution, resulting in permanent charge separation. The advantage of long-lived charge separation can be exploited for useful chemistry if suitable catablysts can be assembled on the zeolities. We have studied Ru(bpy)2 as water oxdiation catalysts. We have demonstrated that synthesis of RuO2 fibers on a zeolite via thermal decomposition of Ru3(CO)12 leads to the most active water decomposition catalyst reported to date. Because of the extensive interest of photochemical water reduction to H2, much is known about catalytic systems usin gone electron catalyst, and even more importantly, that no reaction of viologen occurred with H2 over this catalyst. The present challenge is to incorporate all these elements of the system into an architecture and we are examining zeolite membranes for this purpose.

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