• Electrical & Electronic Materials
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• v.10 no.8
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• pp.778-782
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• 1997

In this paper the electronic and optical properties of various poly(3-alkylthiophene)s differing in alkyl chain length were investigated. And their dependence on temperature were also investigated. The electrical conductivity decreased with the increase of alkyl chain length. In addition optical properties were changed due to the shift of edge energy which was caused by the change of the alkyl chain length and rise of temperature. The conformational change of poly(3-alkylthionphene) depending on the alkyl chain length is believed to be responsible to the change of electronic and optical properties of materials.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3711-3718
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• 2012

Here, we report a chain-length dependent morphology and pore structure tailing of mesoporous silica templated from organogels, which is formed by primary alkylamine and ethylene glycol at room temperature. As the chain length of alkylamine changes from 12 to 18, the resulted materials exhibit a morphology change from layers to spheres and platelets, respectively. SEM and TEM observation revealed that these shapes appear to be inherited from their parent organogels. Further pore structure characterization by nitrogen sorption analysis demonstrates that all the resulted silicas exhibit typical IV isotherms indicative of uniform mesopores, and their pore sizes are dependent on the chain length of alkylamine used.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.495-498
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• 2000

In this paper, generation form of displacement current was compared and measured with air-water interfacing induce monolayers which 8A5H with azobenzene and arac.acid mixed. Light response of two monolayers which chain length are different was compared and measured though they are the same isomer. The experimental results are as following; In the displacement current form of mixed monolayers and 8A5H, mixed monolayers which chain length is longer than that of 8A5H caused the displacement current about 40[fA] mole. This is the reason chain length of hydrophobicity in mixed monolayers is longer than that of 8A5H In the case of light stimulus mixed monolayers reacted less than 8A5H about 9[fA]. This is the reason molecule dynamic behaviour in cia and trans was net activated due to its very long chain length.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.04b
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• pp.143-146
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• 2000

We studied effects of alkyl($C_nH_{2n+1}$) chain length on characteristics of poly(3-alkylthiophene) electroluminescent diodes. Among the poly(3-alkylthiophene), poly(3-hexylthiophene)(n=6) and poly(3- octyIthiophene)(n=8) were mainly used for the emitting layer of the diode. The result of experiment, the emission intensity of poly(3-alkylthiophene) electroluminescent diodes depends on the alkyl chain length. Strong emission is obtained from a poly(3-alkylthiophene) diodes of long alkyl side chain length. Emission intensities are enhanced by a confinement of carriers on a main chain with a long interchain distance caused by a long alkyl side chain.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.50-54
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• 2001

The amylose content, based on iodine blue value, of eight rice cultivars decreased in order of Nampungbyeo>Whachungbyeo>Punchilmi>Nampung CB243>Whachung du-1>Nampung EM90>Whachungchalbyeo>shr. The amylopectin chain length distribution was obtained by enzyme treatments followed by high-performance size-exclusion chromatographic separation. Chain length distribution profiles of the isoamylase-debranched starches showed distinct patterns according to cultivars. Based on the sensory evaluation result of the bread prepared from gluten and rice flours of eight rice cultivars, chewiness of the product was related with the presence of amylose while the short-chain amylopectin fraction was contributed to the texture and overall quality.

• The Microorganisms and Industry
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• v.26 no.2
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• pp.2-12
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• 2000

• Food Science and Biotechnology
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• v.14 no.4
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• pp.470-473
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• 2005

Starch was isolated from turnip (Brassica rapa L.), and to elucidate the structure-function relationship its structural and physical properties were characterized. Morphological structure of the starch was analyzed by SEM (Scanning Electron Microscopy). Most of the starch granules were spherical in shape with diameter ranging from 0.5-10mm. Apart from larger granules ($<10\;{\mu}m$) which dominated the population size of turnip starch, significant amount of small ($0.5-2\;{\mu}m$) and mid-size granules (${\sim}\;{\mu}m$) were also detected. It was revealed that presumably, erosion damages occurred due to the attack of amylase-type enzymes on the surface of some granules. Branch chain-length distribution was analyzed by HPAEC (High-Performance Anion-Exchange Chromatography). The chain-length distribution of turnip starch revealed a peak at DP12 with obvious shoulder at DP18-21. The weight-average chain length ($CL_{avg}$) was 16.6, and a large proportion (11.8%) of very short chains (DP6-9) was also observed. The melting properties of starch were determined by DSC (Differential Scanning Calorimetry). The onset temperature ($T_o$) and the enthalpy change (${\Delta}H$) of starch gelatinization were $50.5^{\circ}C$ and 12.5 J/g, respectively. The ${\Delta}H$ of the retrograded turnip starch was 3.5 J/g, which indicates 28.2% of recrystallization. Larger proportion of short chains as well as smaller average chain-length can very well explain relatively lower degree of retrogradation in turnip starch.

• Journal of applied mathematics & informatics
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• v.24 no.1_2
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• pp.505-511
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• 2007

In this paper, we examine the Markov chain $\{X_k,\;N_k;\;k=0,\;1,...$. We show that the marginal steady state distribution of Xk is discrete phase type. The implication of this result is that the queue length distribution of phase type for large number of examples where this Markov chain is applicable and shows a queueing application by matrix geometric methods.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.5
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• pp.1058-1063
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• 1997

Though the Preparata code of length 8 over $Z_{4}$ satisfies the chain condition, the Preparata code of length 16 or 32 over $Z_{4}$ does not satisfy the chain condition. In this paper we show that the Preparata code of length $2^{m}$ over $Z_{4}$ does not satisfy the chain condition for m=4, 5, 6 and 8 by investigating relations between weight hierarchy and chain condition.

• KSTLE International Journal
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• v.6 no.1
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• pp.13-16
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• 2005

Friction characteristics at nano-scale of self-assembled monolayers (SAMs) having different chain lengths and end groups were experimentally studied.51 order to understand the effect of the chain length and end group on the nano-scalefriction: (1) two different SAMs of shorter chain lengths with different end groups such as methyl and phenyl groups, and (2)four different kinds of SAMs having long chain lengths (C10) with end groups of fluorine and hydrogen were coated on siliconwafer (100) by dipping method and Chemical Vapour Deposition (CVD) technique. Their nano-scale friction was measuredusing an Atomic Force Microscopy (AFM) in the range of 0-40 nN normal loads. Measurements were conducted at the scanning speed of 2 $mu$m/s for the scan size of 1$mu$m x 1 $mu$m using a contact mode type $Si_3N_4$ tip (NPS 20) that had a nominal spring constant0.58 N/m. All experiments were conducted at anlbient temperature (24 $pm$1$circ$C) and relative humidity (45 $pm$ 5%). Results showedthat the friction force increased with applied normal load for all samples, and that the silicon wafer exhibited highest frictionwhen compared to SAMs. While friction was affected by the inherent adhesion in silicon wafer, it was influenced by the chainlength and end group in the SAMs. It was observed that the nano-friction decreased with the chain length in SAMs. In the caseof monolayers with shorter length, the one with the phenyl group exhibited higher friction owing to the presence of benBenerings that are stiffer in nature. In the case of SAMs with longer chain length, those with fluorine showed friction values relativelyhigher than those of hydrogen. The increase in friction due to the presence of fluorine group has been discussed with respect tothe siBe of the fluorine atom.