• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2711-2719
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• 2013

Hydrogen bonding interaction between alcohols and water molecules is an important characteristic in the aqueous solutions of alcohols. In this paper, a series of molecular dynamics simulations have been performed to investigate the aqueous solutions of low molecular weight alcohols (methanol, ethylene glycol and glycerol) at the concentrations covering a broad range from 1 to 90 mol %. The work focuses on studying the effect of the alcohols molecules on the hydrogen bonding of water molecules in binary mixtures. By analyzing the hydrogen bonding ability of the hydroxyl (-OH) groups for the three alcohols, it is found that the hydroxyl group of methanol prefers to form more hydrogen bonds than that of ethylene glycol and glycerol due to the intra-and intermolecular effects. It is also shown that concentration has significant effect on the ability of alcohol molecule to hydrogen bond water molecules. Understanding the hydrogen bonding characteristics of the aqueous solutions is helpful to reveal the cryoprotective mechanisms of methanol, ethylene glycol and glycerol in aqueous solutions.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.733-736
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• 2007

We have proposed novel bonding technique of substrates for developing the flexible LCD with high quality. The gel type mixture of agarose and UV curable epoxy developed to obtain tight bonding ability and enhanced electro-optical characteristic simultaneously. This technique can be used to roll-to-roll process for fabricating the flexible LCDs.

• ETRI Journal
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• 제37권5호
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• pp.951-960
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• 2015

For a conventional power metal-oxide-semiconductor field-effect transistor (MOSFET), there is a trade-off between specific on-state resistance and breakdown voltage. To overcome this trade-off, a super-junction trench MOSFET (TMOSFET) structure is suggested; within this structure, the ability to sense the temperature distribution of the TMOSFET is very important since heat is generated in the junction area, thus affecting its reliability. Generally, there are two types of temperature-sensing structures-diode and resistive. In this paper, a diode-type temperature-sensing structure for a TMOSFET is designed for a brushless direct current motor with on-resistance of $96m{\Omega}{\cdot}mm^2$. The temperature distribution for an ultra-low on-resistance power MOSFET has been analyzed for various bonding schemes. The multi-bonding and stripe bonding cases show a maximum temperature that is lower than that for the single-bonding case. It is shown that the metal resistance at the source area is non-negligible and should therefore be considered depending on the application for current driving capability.

• 한국전기전자재료학회논문지
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• 제11권12호
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• pp.1079-1083
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• 1998

In this study, ultrasonic power of Aluminum wire bonder, bond time and bond force are investigated and valued in order to minimize failure of bonding pad lift. We also tried to control those 3 factors properly. We got the conclusion that if we turn down the ability of ultrasonic power or bond time, we can get a pad lift from a boundary between bond pad ad wire because pad metal and wire joining is unstable, but it is best condition when it ultrasonic power is 100∼130unit, bond time is 15∼20msec and bond force is 4∼6gf.

• Restorative Dentistry and Endodontics
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• 제21권1호
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• pp.187-201
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• 1996

The purpose of this study was to evaluate the sealing ability of a calcium hydroxide plug treated with a bonding agent. Ninety extracted human anterior teeth and premolars with single canal were used in this study. Crowns were removed. the canal's were instrumented. and the roots were randomly divided into three groups of 30 each. In control group. a single apical seat was prepared with #60 K file 1mm short of the apex and the root canal was obturated with Gutta-percha and Sealapex by the lateral condensation method. In experimental group 1 and group 2. to prepare an apical isthmus of 1mm in length. the first apical seat was prepared with a #45 K file 1mm short of the anatomical apex and with a #60 K file 2mm short for the second apical seat. Dry calcium hydroxide powders were packed in the apical isthmus with a hand plugger and #60 K file and then. the root canal was obturated with Gutta-percha and Seal apex by the lateral condensation method. In experimental group 2. following an application of the bonding agent to the plug. the root canal was obturated in the same way. The teeth of each group were immersed in a 2% methylene blue dye solution. for 1, 2, and 4 weeks. The distance from the tip of the cone to the deepest penetration was measured using the Tool maker's microscope. The results were as follows : 1. The teeth having the calcium hydroxide plug treated with the dentin bonding agent (experimental group 2) showed the lowest leakage with 1.4705mm and the control group without apical plug(no apical isthmus) showed the highest leakage with 3.1735mm. 2. The control group without apical plug showed higher leakage than experimental group 1 having the calcium hydroxide plug treated without the dentin bonding agent(p>0.05). 3. The control group without apical plug and experimental group 1, having the calcium hydroxide plug treated without the dentin bonding agent. showed higher leakage than experimental group 2. having the calcium hydroxide plug treated with the dentin bonding agent(p<0.001). 4. The immersion time had no significant effect on the degree of leakage. In conclusion, the results showed that the calcium hydroxide plug treated with the dentin bonding agent could decrease the microleakage from the root apex effectively.

• 한국과학교육학회지
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• 제37권1호
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• pp.39-48
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• 2017

이 연구에서는 고등학교 학생들이 이온 결합에 대해 생성한 비유의 특징을 비유 생성 개수와 대응 관계 이해도, 비유의 소재와 유형의 측면에서 분석하고, 이 결과를 학생들의 개념 이해도와 논리적 사고력, 비유 추론 능력에 따라 비교하였다. 서울특별시에 소재한 5개 고등학교에 재학 중인 2학년 학생 395명이 연구에 참여하였다. 연구 결과, 개념 이해도, 논리적 사고력, 비유 추론 능력이 높을수록 학생들은 비유를 더 많이 생성하는 것으로 나타났다. 생성한 비유에 대한 대응 관계 이해도는 논리적 사고력과 비유 추론 능력만 관계가 있었다. 학생들이 비유를 생성하기 위해 활용하는 소재는 조사한 인지적 특성 중 목표 개념에 대한 이해도에 따라서만 다르게 나타났다. 또한, 개념 이해도가 높을수록 다양한 소재를 활용하여 비유를 생성하였다. 학생들이 생성한 비유의 유형은 일부 인지적 특성과 관련이 있었다. 예를 들어, 개념 이해도와 논리적 사고력이 높은 학생들이 글과 그림을 모두 사용한 비유를 더 많이 생성하였다. 작위성과 추상도, 체계성의 측면에서 비유의 유형은 인지적 특성과 관련이 없었다. 이상의 결과를 바탕으로 교육적 함의를 논의하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2004년도 학술대회지
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• pp.21-26
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• 2004

This study deals with the Hydrated Ability of the Ready-Mixed Concrete's Sludge which is the recycling technology of that sludge. The experiment gathers sludge from Ready-mixed factory. shatters these into pieces in dry condition and understands the differences between current using Portland cement. And then. this examines the possibility of the recycle as a bonding agent through the Compressive Strength and considers the recovery of the hydration. This experiment concludes the same Chemical Composition with the normal Portland cement. while. under the appropriate procedure in hydration recovery. this sludge can be used as the bonding agent in cement. The chemical composition of solid Remicon sludge shows that it has 1.8 times $SiO_2$ than the normal Portland cement. meaning lots of aggregate in Remicon sludge. Also. the specific gravity of Remicon sluge increases with the rise of Baking Temperature and has no difference between 2.77 and 2.94. The mortar flow used for combining the baking material of Remicon sludge does was not changed and is the highest between $750^{\circ}C{\cdot}120min\;and\;800^{\circ}C{\cdot}180min$. Additionally. the Compressive Strength increases with the age, certifying the same Hydrated Ability like cement and the best condition for hydration is $750^{\circ}C{\cdot}120min.$

• 한국실내디자인학회논문집
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• 제22권5호
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• pp.367-375
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• 2013

Using the 'New material' concept has recently been introduced into the natural characteristics. In the course of such a, Janine M. Benyus has proposed to mimic the characteristics of natural ecosystems to mention the concept of Biomimicry. Process made engineered using technical elements for representing the material properties of Biomimicry such will be acting importantly, This study intends to analyze how new materials applied to 'Biomimicry' characteristics are processed in space. The results were as follows : 1) Processing methods of new materials resulted as 'Forming', 'Surface treatment', 'Bonding', 'Inserting'. These four were divided and analyzed into 'Form', 'System', 'Adaptation'. As a result of this analysis, such significances were shown as 'Forming/Surface treatment/Bonding' in 'Form', 'Bonding' in 'System' and 'Adaptation'. 2) 'Bonding' applied to 'System' of new material can be recycled to be combined with other materials through the existing adhesive material, and present as a solution of 'Sustainable development'. 3) 'Bonding' applied to 'Adaptation' of new material is to impart the ability to react to the environment through the joint, but is characteristic, at this time, using digital and other field technology. It appeared primarily that it can be known to meet the social trends and convergence between fields. Thus, as the finish that are friendly to the environment from the interior design, the results of the study are expected to be utilized in the study of new materials guidelines.

• 한국재료학회지
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• 제22권4호
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• pp.211-214
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• 2012

Optimal conditions for HA plasma spray-coating on Ti6Al4V alloy were investigated in order to obtain enhanced bone-bonding ability with Ti6Al4V alloy. The properties of plasma spray coated film were analyzed by SEM, XRD, surface roughness measurement, and adhesion strength test because the film's transformed phase and crystallinity were known to be influential to bone-bonding ability withTi6Al4V alloy. The films were formed by a plasma spray coating technique with various combinations of plasma power, spray distance, and auxiliary He gas pressure. The film properties were analyzed in order to determine the optimal spray coating parameters with which we will able to achieve enhanced bone-bonding ability with Ti6Al4V alloy. The most influential coating parameter was found to be the plasma spray distance to the specimen from the spray gun nozzle. Additionally, it was observed that a relatively higher film crystallinity can be obtained with lower auxiliary gas pressure. Moderate adhesion strength can be achievable at minimal plasma power. That is, adhesion strength is minimally dependent on the plasma power. The combination of shorter spray distance, lower auxiliary gas pressure, and moderate spray power can be recommended as the optimal spray conditions. In this study, optimal plasma spray coated films were formed with spray distance of 70 mm, plasma current of 800 A, and auxiliary gas pressure of 60 psi.

• 한국주조공학회지
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• 제25권3호
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• pp.134-141
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• 2005

To overcome the undesirable deformation, peeling off and geometrical restrictions which were mainly caused by differences in thermal expansion coefficients during the cladding of aluminum strip and stainless strip, new processing method based on vacuum die casting is designed and implemented in fabricating Al/Fe-17wt%Cr steel(stainless steel). To increase cast-bonding ability, the surface of Fe-17wt%Cr steel is electrochemically etched to have optimum pit size and density. The optimum conditions to generate best pit are as follows: Solution: 1 M $Fecl_{3}$+1 M Nacl, Addition: $CuCl_{2}+HCl$, Current density: 80 $mA/cm^{2}$, Total current: 400 $coulomb/cm^{2}$, AC frequency :60 Hz.