• Applied Chemistry for Engineering
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• v.26 no.2
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• pp.128-131
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• 2015

Hydration of nitriles in the environmentally benign neutral conditions is the most economical and attractive way to produce amides. Substantial research works have been carried out to apply the solid metal oxides and transition metal supported catalytic systems to promote the hydration of nitriles. The most significant feature of these catalysts is the applicability to a wide range of substrates including aromatic, alicyclic, hetero-atomic, and aliphatic nitriles. These catalysts are also characterized by the easy isolation from the reaction mixture and the reusability while maintaining the high catalytic activity. This review accounts over the detailed survey of the metal oxide and solid supported metal catalysts for preparing amides from the hydration of nitriles.

• Textile Coloration and Finishing
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• v.8 no.2
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• pp.64-70
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• 1996

Wool yarns were treated in dimethylformamide solutions containing various concntrations of three dibasic acid anhydrides: succinic, itaconic, and phthalic arthydrides in various conditions. The structurl aspects of these dibasic acid anhydries are different: succinic, itaconic, and phthalic acid arthydrides have saturated aliphatic ethylene, unsaturated aliphatic vinyl and aromatic phenyl one groups, respectively. The properties of acylated wool keratin are as follows: Decreasing amino group and increasing carboxyl group by acylation lowered the hydrophilic property, and then moisture regain, and decreased acid dye uptake and enhanced cationic dye uptake of wool keratin. In the case of phthalic acid anhydries, in spite of lowest acyl content, the minimum of moisture regain was resulted from the bulk benzen ring, occuping much more voids on wool keratin molecules than other reagents. Acid solubility was increased by the decrease of amino group and hydrogen bonding by acylation. Alkali solubility was also increased formation of new amide group on the side chain of keratin, which can be degraded easily by alkali. In the case of phthalic acid anhydride, the relative high solubility was resulted from the much higher molecular weight of dissolved fractions. The surface of wool keratin was not damaged by treatment with any acylating agent.

• Korean Journal of Weed Science
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• v.10 no.3
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• pp.227-232
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• 1990

The effects of alachlor [2-chloro-2', 6' diethyl-N-(methoxymethyl) acetanilide] treatment on nucleic acid, amino acid and protein synthesis were studied. The amide herbicide alachlor blocks the biosynthesis of the amino acids isoleucine, valine and aromatic amino acid in oat root tips. Nucleic acid was inhibited, but was not proportional to reduction in protein synthesis. $1{\times}10^{-4}M$ of alachlor treatment of oat roots inhibited 36% DNA synthesis, but DNA synthesis was not inhibited at $1{\times}10^{-5}M$. RNA synthesis was inhibited by $1{\times}10^{-5}M$ and $1{\times}10^{-4}M$ of alachlor 16 and 27%, respectively, while inhibition of protein synthesis did occur at same concentrations. Inhibition of protein synthesis also did not occur at concentration below $1{\times}10^{-4}M$ alachlor. It suggest that inhibition of protein sythesis caused significantly by alachlor($1{\times}l0^{-3}M$) result from secondary action.

• Textile Coloration and Finishing
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• v.25 no.4
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• pp.292-302
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• 2013

Cotton fabrics treated with hybrid materials were developed and prepared. A halogen-free flame retardant and an aromatic amide were blended and applied to cotton fabrics. Thermal and physical properties of the treated cotton fabrics were investigated. The surface of the pure and coated cotton fabrics was characterized by Fourier transform infrared spectroscopy. The elemental composition of the coated surface of the cotton fabric was measured using X-ray photoelectron spectroscopy and compared with that of pure cotton fabric. After being solved in N,N-dimethylacetamide, m-aramid and triphenylphosphine oxide (TPP) were applied to cotton fabrics through a dip-pad-coagulation process. The treated cotton fabrics with recycled m-aramid/TPP resulted in increased limited oxygen index values and thermal resistance.

• Journal of the Optical Society of Korea
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• v.10 no.1
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• pp.1-10
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• 2006

Optical transparency and high diffraction efficiency are two essential factors for high performance of the photopolymer. Optical transparency mainly depends on the miscibility between polymer binder and photopolymerized polymer, while diffraction efficiency depends on the refractive index modulation between polymer binder and photopolymerized polymer. For most of organic materials, the large refractive index difference between two polymers accompanies large structural difference that leads to the poor miscibility and thus poor optical quality via light scattering. Therefore, it is difficult to design a high-performance photopolymer satisfying both requirements. In this work, first, we prepared a new phase-stable photopolymer (PMMA) with large refractive index modulation and investigated the optical properties. Our photopolymer is based on modified poly (methyl methacrylate) as a polymer binder, acryl amide as a photopolymerizable monomer, triethanolamine as initiator, and yellow eosin as a photosensitizer at 532 nm. Diffraction efficiency over 85% and optical transmittance over 90% were obtained for the photopolymer. Second, Organic-inorganic nanocomposite films were prepared by dispersing an aromatic methacrylic monomer and a photo- initiator in organic-inorganic hybrid sol-gel matrices. The film properties could be controlled by optimizing the content of an organically modified silica precursor (TSPEG) in the sol-gel matrices. The photopolymer film modified with the organic chain (TSPEG) showed high diffraction efficiency (> 90%) under an optimized condition. High diffraction efficiency could be ascribed to the fast diffusion and efficient polymerization of monomers under interference light to generate refractive index modulation. The TSPEG modified photopolymer film could be successfully used for holographic memory.

• ETRI Journal
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• v.26 no.1
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• pp.38-44
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• 2004

Searching for systems of self-assembled monolayers (SAMs) that can be used as templates for chemical lithography, we found that nitro groups on aromatic SAMs are selectively converted on Ag to amino groups by irradiation with a visible laser. 4-nitrobenzenethiol on Ag was thus converted to 4-aminobenzenethiol by irradiating it with an $Ar^+$ laser. This was evident from surface-enhanced Raman scattering (SERS) as well as from a coupling reaction forming amide bonds. The surface-induced photoreaction allowed us to prepare patterned binary monolayers on Ag that showed different chemical reactivities. Using the binary monolayers as a lithographic template, we induced site-specific chemical reactions, such as the selective growth of biominerals on either the nitro- or amine-terminated regions by adjusting the crystal-growth conditions. We also demonstrated that patterned, amine-terminated monolayers can be fabricated even on gold by using silver nanoparticles as photoreducing catalysts.

• Korean Journal of Crystallography
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• v.8 no.1
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• pp.59-63
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• 1997

A method for the calculation of the idealized hydrogen positions in the following seven different kinds of compounds has been shown: (1) tertiary C-H, (2) secondary C-H, (3) $CH_3$ group with tetrahedral angles, (4) aromatic C-H or amide N-H, (5) O-H group with X-O-H angle tetrahedral, (6) terminal $X=CH_2$ or $X=NH_2^+$ with the hydrogen atoms in a plane and (7) acetylenic C-H with X-C-H linear.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.1
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• pp.43-47
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• 2020

A novel series of adamantyl derivatives of N-aryl amides as androgen receptor antagonists were synthesized and their anti-androgenic activities were evaluated. The N-aryl amides containing adamantyl derivatives had more activity than those lacking adamantyl substitutions. The synergistic effect of bulkiness of the adamantyl group and modulation of electron density on the aromatic ring by pendant groups was crucial to the potent antagonism. Molecular modeling studies were performed to elucidate the interactions between ligands and receptors.

• Mass Spectrometry Letters
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• v.10 no.2
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• pp.50-55
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• 2019

The fragmentation statistics of ion trap CID (Collision-Induced Dissociation) spectra using 87,661 tandem mass spectra of doubly charged tryptic peptides are analyzed here. In contrast to the usual method of using intensity information, the frequency of occurrence of fragment ions, with respect to the position of the cleavage site and the residues at these sites is studied in this paper. The analysis shows that the frequency of occurrence of fragment ion peaks is more towards the middle of the peptide than its ends. It was noted that amino acid with an aromatic and basic side chain at N- & C- terminal end of the peptide stimulates more peaks at the lower end of the spectrum. The residue pair effect was shown when the amide bond occurs between acidic and basic residues. The fragmentation at these sites (D/E-H/R/K) stimulates the generation of the y-ion peak. Also, the cleavage site H-H/R/K stimulates the generation of b-ions. K-P environment in the peptide sequence has more tendency to generate y-ions than b-ions. Statistical analysis helps in the visualization of the CID fragmentation pattern. Cleavage pattern along the length of the peptide and the residue pair effects, enhance the knowledge of fragmentation behavior, which is useful for the better interpretation of tandem mass spectra.

• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.576-583
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• 1982

The variation of free amino acids during the tomato producing was studied using a tomato variety, Kagome 77. The concentration of free amino acids in fresh and heated pulp, and in puree and paste was analyzed by using automatic amino acid analyzer, Hitachi model KLA-5. 1. A significant difference in decomposition rate of glutamine and asparagine among amide group was recognized. For instance, the glutamine decomposed fast and no glutamine was found in the paste, while 56% of asparagine was found in the paste. 2. The diminishing quantity of glutamic acid among acid group was highest among all free amino acids. The quantity of aspartic acid was next to the glutamine. The percents of glutamic acid and aspartic acid left over were 38% and 24%, respectively. 3. Glycine, alanine, valine, isoleucine and leucine of neutral amino acids tended to be reduced a little during the heating, concentrating process. 4. No apparent variation was found for the lysine and histidine belonging to basic amino acids. while arginine increased a little. 5. Tyrosine, phenylalanine and tryptophane of aromatic group seemed to increase a little during the heating process. But the variations of them during the concentrating process were not recognized. 6. The methionine content, sulfur containing amino acid decreased a little throughout the process. But the decrease of ${\gamma}-amino$ butyric acid of non-protein was not apparently recognized. 7. The amino acid contents of fresh pulp were found as following order: glutamic acid>${\gamma}$-amino butyric acid>glutamine>aspartic acid>asparagine. The amino acid contents of paste were as glutamic acid>${\gamma}$-amino butyric acid>aspartic acid and aspargine. The percent distribution of aromatic and basic amino acids increased, even it was not great. 8. When amino acids were analyzed by Hitachi KLA-5, unknown peak which was never app eared in the fresh pulp before tryptophane was appeared when processed. The peak became greater when heated and concentrated. Later it was known that the peak was not due to lysinoalanine or ornithine.