• Macromolecular Research
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• v.11 no.5
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• pp.322-327
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• 2003

Two kinds of mutually cross-linkable copolymers were prepared to be used as humidity-sensing materials. The humidity-sensitive thin films consist of cross-linked polyelectrolytes of the following component: 4-vinylbenzyl dimethyl 2-(dimethylphosphino)ethyl phosphonium chloride (1)/ bis(2-methoxyethyl)itaconate (2)= 3/l, 2/l, 1/1 and 1/2 and 4-vinylbenzyl chloride (3)/ vinylbenzyl tributyl phosphonium chloride (4)= 3/l, 2/l, 1/1 and 1/2. The humidity sensor prepared from the reaction of 1/2= 2/l with 3/4= 2/l showed an average resistance of 723,36.2 and 2.42 ㏀ at 30, 60 and 90%RH, respectively. Temperature dependence, frequency dependence, and response time were measured and the reliability test such as water durability and long-term stability were also estimated.

• Bulletin of the Korean Chemical Society
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• v.22 no.7
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• pp.732-738
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• 2001

The cross second-derivative of the activation energy,${\theta}$G${\neq}$ , with respect to the two component thermodynamic barriers, ${\theta}$G˚X and ${\theta}$G$^{\circ}C$Y, can be given in terms of a cross-interaction constant (CIC), $\betaXY(\rhoXY)$, and also in terms of the intrinsic barrier,${\theta}$G${\neq}$ , with a simple relationship between the two: $\betaXY$ = $-1}(6${\theta}$G${\neq}$).$ This equation shows that the distance between the two reactants in the adduct (TS, intermediate, or product) is inversely related to the intrinsic barrier. An important corollary is that the Ritchie N+ equation holds (for which $\betaXY$ = 0) for the reactions with high intrinsic barrier. Various experimental and theoretical examples are presented to show the validity of the relationship, and the mechanistic implications are discussed.

• Nuclear Engineering and Technology
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• v.46 no.3
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• pp.353-362
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• 2014

The effects of nuclear data uncertainties are studied on a typical PWR fuel assembly model in the framework of the OECD Nuclear Energy Agency UAM (Uncertainty Analysis in Modeling) expert working group. The "Fast Total Monte Carlo" method is applied on a model for the Monte Carlo transport and burnup code SERPENT. Uncertainties on $k_{\infty}$, reaction rates, two-group cross sections, inventory and local pin power density during burnup are obtained, due to transport cross sections for the actinides and fission products, fission yields and thermal scattering data.

• Korean Membrane Journal
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• v.5 no.1
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• pp.10-17
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• 2003

1,3,5-Sustitituted polyphenylene type dendrimers were synthesized. The dendrimer was heated in cone. H$_2$SO$_4$ at 120$^{\circ}C$. The reaction mixture was precipitated to ether after simple filtration to get para-sulfonated dendrimer as the chief product. To give mechanical properties to the sulfonated dendrimer, it was partially cross-linked with phenyl ether in the medium of P$_2$O$\sub$5/ and CH$_3$SO$_3$H.

• Journal of the Korean Graphic Arts Communication Society
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• v.1 no.1
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• pp.57-60
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• 1983

Among the gelatin hardness for photographic emulaion, the formaldehyde, dialdehydes, n-Methylol compounds, ketones, carbonylic acid and carbamic acid derivatives, and s-Triazine derivatives were studied The greater purts of hardeners formed cross-link by the reaction with E-Amino group in the lysine and OH group in the hydroxylysine. Glutaraldehyde produced most stable cross-link due to the formation of pyridinum ion. 2.5- hexanedione and 3-hexene-2,5-dione possible to use as the ketone hardner. The sodium salt of 2.4-dichloro-6-hydroxy-S-Triazine was newly developed as the olefinic hardners for emulsion.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.173.3-173.3
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• 2003

In recent years, olefin cross-metathesis (CM) has emerged as a powerful and convenient synthetic technique in organic chemistry; however, as a general synthetic method, CM has been limited by the lack of predictability in product selectivity and stereoselectivity. A number of excellent studies have recently appeared in the literature which have shown that with the correct catalyst and reaction conditions CM can be used to access a variety of di-and trisubstituted olefinic products in moderate to high yield with good E/Z ratios. (omitted)

• Macromolecular Research
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• v.17 no.10
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• pp.791-796
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• 2009

An electrochemically and photochemically polymerizable monomer, 2-((2,3-dihydrothieno[3,4-b] [1,4]dioxin-2-yl)methoxy)ethyl methacrylate (EDOT-EMA), was explored for patterning of poly(3,4-ethylenedioxythiophene) (PEDOT) via side chain cross-linking. The polymer from EDOT-EMA was deposited electrochemically to produce polymeric EDOT (PEDOT-EMA), which was directly photo-patterned by UV light as the side EMA groups of PEDOT-EMA were polymerized to give cross-linked EMA (PEDOT-PEMA). Absorption and FTIR studies of the UV-exposed film (PEDOT-PEMA) indicated that the photo-patterning mainly originated from the photo cross-linking of the methacrylates in the side-chain. After irradiation of the film, the conductivity of the irradiated area decreased from $5.6{\times}10^{-3}$ S/cm to $7.2{\times}10^{-4}$ S/cm, possibly due to bending of the conductive PEDOT channel as a result of the side chain cross-linking. The patterned film was applied to a solid state electrochromic (EC) cell to obtain micro-patterned EC cells with lines up to 5 ${\mu}m$ wide.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3627-3631
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• 2014

In this study we examined two ester-containing cross-links, hex-2-enyl acetate and hex-2-enyl propionate, as new cross-linking systems for helix stabilization of short peptides. We demonstrated that these hexenyl ester cross-links can be readily installed via a ruthenium-mediated ring-closing metathesis reaction of L-aspartic acid 4-allyl ester or L-glutamic acid 5-allyl ester at position i and (S)-2-(4'-pentenyl)alanine at position i+4 using second generation Hoveyda-Grubbs catalyst at $60^{\circ}C$. Between these two cross-links, we found that the hex-2-enyl propionate significantly stabilizes the ${\alpha}$-helical conformations of short model peptides. The helix-stabilizing effects of the hex-2-enyl propionate tether appear to be as powerful as Verdine's i,i+4 all-hydrocarbon stapling system, which is one of the most widely used and the most potent helix-stabilizing cross-linking systems. Furthermore, the hex-2-enyl propionate bridge is reasonably robust against non-enzymatic hydrolytic cleavage at a physiological pH. While extended studies for probing its chemical scopes and biological applications are needed, we believe that this new helix-stabilizing system could serve as a useful chemical tool for understanding protein folding and designing conformationally-constrained peptide drugs.

• Journal of Nutrition and Health
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• v.37 no.8
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• pp.669-674
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• 2004

The purpose of this study was to develop the antiallergic and hypoallergic fennented soybean foods without side effect. We manufactured Chungkukjang with addition of herbal (aloe, cinamon, licorice root) extract. Sensory evaluation was performed to evaluate the acceptability by the consumer. Clinical evaluation was performed with 10 atopic dermatitis (AD) patients who showed positive reaction with specific IgE and skin prick test. Cross-over study between nonnal Chungkukjang and Chungkukjang with aloe extract was performed. In sensory evaluation, Chungkukjang with aloe extract obtained best score overall. In clinical evaluation, 7 out of 10 AD patients showed positive reaction to soy-bean and 4 out of 10 AD patients showed positive reaction to normal Chungkukjang. 2 out of 10 AD patients showed positive reaction to Chungkukjang with aloe extract. In conclusion, Chungkukjang could be recommended as functional food with hypoallergic effect. As adding aloe extract to Chungkukjang, hypo allergic effect was increased.

• Journal of Korean Association for Spatial Structures
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• v.16 no.2
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• pp.69-77
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• 2016

The purpose of this study is to present a method that can estimate the height of reaction facilities for large structural experiment through load flow as primary design procedure. The characteristic of the load transmission according to the type of experiment was analyzed to obtain tensile and compressive forces occurring on the reaction facilities. Strong walls that are affected by the bending moment is applied the post-tensioning method, and the strong floor under the control of the tension and compression is designed in accordance with the load flow. And the optimum cross-section of the reaction facilities was obtained by comparing the stresses of the tensile stress and crack the concrete. Through validating elastic analysis, the design results were satisfied a given design conditions.