• 반도체디스플레이기술학회지
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• 제7권3호
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• pp.1-4
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• 2008

The chemical shift of SiOC film was observed according to the flow rate ratio. SiOC film had the broad main band of $880\sim1190cm^{-1}$ and the sharp Si-$CH_3$ bond at $1252cm^{-1}$, and the peak position of the main bond in the infrared spectra moved to high frequency according to the increasing of an BTMSM flow rate. So the increment of the alkyl group induced the C-H bond condensation in the film, and shows the blueshift in the infrared spectra. In the case of P5000 system of Applied Materials Corporation, the strong bond of Si-CH3 bond in precursor does not enough to dissociated and ionized, because low plasma energy due to the capactive coupled CVD. Therefore, there was the sharp peak of Si-$CH_3$ bond at $1252cm^{-1}$.

• 한국콘텐츠학회논문지
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• 제20권7호
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• pp.392-403
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• 2020

본 연구는 반려견을 양육하는 소비자를 대상으로 동물등록제에 대한 인식을 구체적으로 확인하고, 반려견에 대한 애착양상에 따라 동물등록제에 대한 인식이나 선호가 달라지는지를 분석하였다. 온라인 설문조사를 통해 250부의 자료를 수집하였고, SPSS 24.0을 이용하여 분석을 실시하였다. 연구결과, 소비자가 반려견과의 관계에서 형성하는 애착의 형태는 동반자적 애착과 정서교감 애착으로 확인되었다. 반려견에 대한 애착양상에 따라 소비자는 단순동거형(25.6%), 친밀동반형(30.4%), 강한유대형(44.0%)의 3개 유형으로 분류되었다. 소비자 유형별로 동물등록제 인지여부 및 등록여부와의 관계에서 통계적으로 유의한 차이가 있었다. 그리고 소비자 유형에 따라 동물등록제에 대한 인식 및 선호도에 있어 통계적으로 유의한 차이가 나타났다. 본 연구는 실효성 있는 동물등록제 개선 방안에 대한 소비자의 인식 및 선호를 실증하여 소비자 지향적인 동물등록제 발전 방향을 제언한다는 점에서 의의를 가진다.

• Bulletin of the Korean Chemical Society
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• 제17권2호
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• pp.168-172
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• 1996

The variations of the structural detail of layered perovskite-type oxides, Na2Ln2Ti3O10 (Ln=La, Nd, Sm, Gd), have been refined by Rietveld analyses of their powder X-ray diffraction data. Although the c-axis strongly decreases from Ln=La to Nd, Sm, or Gd, the length of Na-O bond along the c-axis that is regarded as the sodium layer spacing is not dependent on the unit cell parameter. Such a behavior is explained by the fact that Na-O bond is in competition with Ti-O one of the perovskite slab. Increased covalency of this Ti-O bond by the lattice contraction leads to weakening of the attaching strength of Na ion. This picture is consistent with the experimental observation that Na ion conductivity of Na2Ln2Ti3O10 increases from Ln=La to Nd, Sm, or Gd despite strong contraction of the unit cell volume.

• 동굴
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• 제70호
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• pp.45-50
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• 2006

The magnetic polishing is the useful method to finish using magnetic power of magnet. This method is one of precision polishing techniques and has an aim of the clean technology using for the pure of gas and inside of the clean pipe for transportation. The magnetic abrasive polishing method is not so common for machine that it is not spreaded widely. There are rarely researcher in this field because of non-effectiveness of magnetic abrasive. Therefore, in this paper deals with development of the magnetic abrasive using worthless mineral. In this development, abrasive grain WA and GC used to resin bond fabricated low temperature. And magnetic material was fabricated from the worthless mineral which were closed into 200 mesh grit type. The XRD analysis result show that only WA and GC abrasive and worthless mineral crystal peaks detected which explains resin bond was not any more chemical reaction. From SEM analysis it is found that WA and GC abrasive and worthless mineral were strong bonding with each other by bond.

• 대한치과보철학회지
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• 제34권2호
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• pp.266-276
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• 1996

Numerous factors are known to affect the accuracy of elastomeric impression materials. Factor often overlooked is the quality of the bond between putty and wash during corrective reline impression technique. The putty-wash bond strength must be strong enough to over-come the local stress at putty-wash interface. It is not always possible to avoid saliva contamination in making corrective wash impres-sion. And putty preliminary impression material con be used as a template for provisional restoration. Human saliva and the residual monomer of autopolymerizing acrylic resin are thought to affect the bond strength and the failure type. This study examined the effect of contaminants like human saliva, and residual resin monomer on the putty-wash bond strength and the effectiveness of treatment. 1. Of the tested three brands of Vinyl Polysiloxane impession meterial, Express Exhibited the greatest bond strength followed by Eamix and Perfect showed the lowest putty-wah bond strength. 2. Coating the putty substrates with human saliva did not produce decreased failure load in all the breands of Vinyl Polysiloxane impression meterail. 3. Of the three brands of VPS impression material that were exposed to methhylmethacry-late resin(Jet), only the putty-wash bond strength of the Perfect group diminished signifi-cantly. Moreover, all the specimens from group C of Perfect exhibited adhesive failure. 4. Exposing the substrates to ethylmethacrylate resin(SNAP. diminished the putty-wash bond strength significantly. With Perfect and Examix, failure occurred cohesively through the light-body, whereas with Express, failure occurred adhesive-cohesively. 5. Removing approximately 1mm thickness of the contaminated putty interface was the most effective treatment in countering the undesirable effect caused by residual resin monomer. The putty-wash bond strength of the groups that were treated with 1mm even putty reduction was not significantly different from those of control groups. With Perfect and Examix, cleaning the specimens with gauze soaked in 70% isopropyl alcohol increased the putty-wash bond strength, but was not as effective as 1mm even reduction of contaminated putty substrates. With Express, 70% isoproryl alcohol treatment exhibi0ted comparable putty-wash bond strength to that of control group.

• Bulletin of the Korean Chemical Society
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• 제18권10호
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• pp.1090-1093
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• 1997

The solvent effects on the isotropic NMR shifts in conformationally rigid ligands such as quinuclidine, pyridine, and 4-aminopyridine coordinated to the paramagnetic polyoxometalate, [SiW11CoⅡO39]6- (SiW11Co), are reported. For these complexes the ligand exchange is slow on the NMR time scale and pure 1H NMR signals have been observed at room temperature. The signals for the SiW11Co complexes are shifted upfield whe dimethyl sulfoxide-d6 (DMSO) is added to a D2O solution. The isotropic shifts are separated into contact and pseudocontact contributions by assuming that the contact shifts are proportional to the isotropic shifts of the same ligands coordinated to [SiW11NiⅡO39]6-. It is shown that both the contact and pseudocontact shifts decrease (the absolute values of the pseudocontact shifts increase), when D2O is replaced by DMSO. It is suggested that D2O, a strong hydrogen bond donor, withdraws electron density from [SiW11CoⅡO39]6-, increasing the acidity of the cobalt ion toward the axial ligand. When D2O is replaced by DMSO, the acidity of the cobalt ion in SiW11Co decreases, weakening the Co-N bond. Then both the contact and pseudocontact shifts are expected to decrease in agreement with the observed solvent effects.

• 한국재료학회지
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• 제12권4호
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• pp.274-278
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• 2002

Discrete-variational(DV)-$X{\alpha}$ method was applied to investigate the electronic structures of spinel- type manganese oxide which is well known to the high performance adsorbent or cathode material for lithium ion. The results of DOS(density of states) and Mulliken population analysis showed that Li was nearly fully ionized and interactions between Mn and O were strong covalent bond. The effective charge of Li and Mn was +0.77 and +1.44 respectively and the overlap population between Mn and O was 0.252 in $LiMn_2O_4$. These results from DV-X$\alpha$ method were well coincided with the experimental result by XPS analysis and supported the feasibility of theoretical interpretation for the $LiMn_2O_4$ compound.

• Bulletin of the Korean Chemical Society
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• 제24권8호
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• pp.1215-1218
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• 2003

An analysis of the bonding situation in CaM₂P₂ (M=Fe, Ni) with ThCr₂Si₂ structure is made in terms of DOS and COOP plots. The main contributions to covalent bonding are due to M-P and P-P interactions in both compounds. Particularly, the interlayer P-P bonding by variation in the transition metal is examined in more detail. It turns out that the shorter P-P bonds in CaNi₂P₂ form as a result of the decreasing electron delocalization into ${{\sigma}_p}^*$ of P₂ due to the weaker bonding interaction between the metal d and ${{\sigma}_p}^*$ as the metal d band is falling from Fe to Ni.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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• pp.75-82
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• 2001

Finite element analysis using ANSYS program conducted to evaluate the tensile behavior of the connection between reinforced concrete and steel members is presented in this paper. It is assumed that there is a complete bond between head part of the stud and concrete. However, the surface of the column area of stud is separated from the concrete to stop the stress transmission between those. In case of using reinforcement connectors such as C or U type, the interface between concrete and reinforcement is idealized to have strong adhesion. Four concrete-steel specimens which are connected by stud connector or reinforcement connectors are compared and analyzed From the comparison, it was shown that the connection between concrete and steel could be predicted by using the modeling technique used in this paper.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.1334-1337
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• 2009

A SMART anchor is a kind of friction mount anchor, the load is diffused and applied to the various parts of the distributed bond length, having less impact on the grout strength, and being able to secure necessary anchoring force in relatively soft grounds. Smart anchor can have strong loads in soft and weak grounds as in rock beds.