• 약학회지
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• 제7권2_3호
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• pp.51-54
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• 1963

In this experiment, it is found that the decomposition reaction of hexamine aqueous solution by heat is the pseudo first order reaction and the calculated decomposition velocity constants of Hexamine aqueous solution are 1.17 * $10^{-5}min.^{-1}(60{\deg}$ C), 1.99 * $10^{-5}min.^{-1}(70{\deg}$ C), 2.35 * $10^{-5}min.^{-1}(80{\deg}$ C), 6.63 * $10^{-5}min.^{-1}(100{\deg}$ C). In the result, the activation energy of decomposition reaction of hexamine aqueous solution is 12 $Cal.mole^{-1}$.

• 대한화학회지
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• 제18권2호
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• pp.132-137
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• 1974

酸性 mucopolysaccharide는 鯨胎兒의 nucleus pulposus에서 分離하였다. Gel electophoresis에 있어서 酸性 mucopolysaccharide의 分離는 $0.03{\%}$의 hexamine cobaltic chloride 를 含有하는 0.05M 醋酸소-다 緩衝溶液(pH4.8)中에서 가장 좋았다. Spacer gel 上의 mucopolysaccharide 溶液을 $40{\%}$ sucrose 溶液으로 덮었을 때 mucopolysaccharide의 移動度에 變化가 나타나는 것을 觀察하였으며 이 효과는 醋酸소-다 緩衝溶液에 hexamine cobaltic chloride 을 加하면 消失하는 것을 觀察하였다.

• 한국가구학회지
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• 제14권2호
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• pp.1-12
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• 2003

This study was carried out to determine the mechanical and physical properties of particle boards glued with condensed tannin (Wattle Tannin) powder that was single-molecule phenolic compounds like powdered phenolic resin. Our findings are; 1) It is necessary to spray water on the chip surfaces for effective application of powdered -form tannin resin. It shows that the best and optimum mat moisture increase is 14% of water spray on the surface of chips for developing PB properties. 2) In general, for both liquid and powdered tannin adhesives, their physical and mechanical properties has been proportional to the increase of resin level. But, the most efficient addition ratio is 16% of resin on dry basis. Specially, it is found that the resin level influences on the amount of free formaldehyde emission. The higher the resin level is, the lower the emission is. These phenomena seem to result from the increase of hexamine or formaline in the adhesives used as a hardener, that reduce the free-formaldehyde amount by reaction of tannin of poly-molecule and water. 3) The optimum condition for manufacturing PBs is the condition of hexamine of 5% and formaline of 6% in mechanical and physical properties. Hexamine is superior to formaline in mechanical and physical properties along with the control of the free formaldehyde emission amount. The result of NaOH's addition is insignificant in all experiments of both mechanical and physical properties.

• Bulletin of the Korean Chemical Society
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• 제28권4호
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• pp.589-595
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• 2007

The conversion of both the racemic and resolved forms of the Co(III) complex of an hydroxymethyl-substituted tripodal hexamine to macrobicycles via reaction with formaldehyde and nitromethane (and subsequent reduction of the product) has been conducted. The prospect is that it will provide cage complexes in which the hydroxyl substituent is sufficiently remote from the metal ion centre for its nucelophilicity to be largely unaffected. X-ray structure determinations have been used to characterise these new cage species as well as some complexes of the precursor hexamine and its mono-aminal. The electrochemistry and optical activity of the complexes have also been studied in detail.

• Bulletin of the Korean Chemical Society
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• 제17권11호
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• pp.977-979
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• 1996

• 전기학회논문지
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• 제65권11호
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• pp.1835-1839
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• 2016

In this study, ZnO nanorods were grown by a hydrothermal method. $SiO_2/Si$ wafers and glass were used as substrates. ~20 nm-thick ZnO thin films were rf magnetron sputtered for seed layers. The precursor was prepared by mixing zinc nitrate hexahydrate and hexamethylenetetramine (hexamine) in DI water. The concentration of zinc nitrate hexahydrate was fixed at 0.05 mol, and that of hexamine was varied between 0 mol to 0.1 mol. The reactor containing substrates and precursor was put in an oven maintained at $90^{\circ}C$ for 1 h. X-ray diffraction was carried out to analyze the crystallinity of ZnO nanorods, and a field emission scanning electron microscope was employed to observe the morphology of nanorods. Transmittance and absorbance were measured by a UV-Vis spectrophotometer. Photoluminescence measurements were conducted using 266 nm light.

• Journal of the Korean Wood Science and Technology
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• 제33권2호통권130호
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• pp.29-39
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• 2005

Formaldehyde emissions from wood-based panels bonded with pine and wattle tannin-based adhesives, urea-formaldehyde resin (UF), melamine-formaldehyde resin (MF), and co-polycondensed resin of urea-melamine-formaldehyde (UMF) were measured by the Japanese standard method using a desiccator (JIS A 1460) and the EN 120 (European Committee For Standardization, 1991) method using the perforator value. In formaldehyde emission, all particleboards made using the wattle tannin-based adhesive with three different hardeners, paraformaldehyde, hexamethylenetetramine, and tris(hydroxyl)nitromethan (TN), satisfied the requirements of grade $E_1$. But only those made using the pine tannin-based adhesive with the hexamine as hardener met the grade $E_1$ requirements. Hexamine was effective in reducing formaldehyde emission in tannin-based adhesives when used as the hardener. While the UF resin showed a desiccator value of $7.1mg/{\ell}$ and a perforator value of 12.1 mg/100 g, the MF resin exhibited a desiccator value of $0.6mg/{\ell}$ and a perforator value of 2.9 mg/100 g. According to the Japanese Industrial Standard and the European Standard, the formaldehyde emission level of the MDF panels made with UF resin in this study came under grade $E_2$. The formaldehyde emission level was dramatically reduced by the addition of MF resin. The desiccator and perforator methods produced proportionally equivalent results. Gas chromatography, a more sensitive and advanced method, was also used. The samples for gas chromatography were gathered during the experiment involving the perforator method. The formaldehyde contents measured by gas chromatography were directly proportional to the perforator values.

• 폴리머
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• 제32권1호
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• pp.1-6
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• 2008

Acrylonitrile butadiene rubber(NBR)의 접착력 및 가공성을 향상시키기 위한 연구를 하였다. 최상의 조건을 선별하기 위해서 NBR의 acrylonitrile(ACN) 함량에 따른 접착물성 및 가공성을 관찰하였다. 무늬 점도, 충전제, 가소제 및 가교제가 접착력에 미치는 영향도 조사하였다. NBR의 ACN 함량은 NBR sealing에서 접착거동 및 가공성에 큰 영향을 미침을 알 수가 있었다. 최상의 혼합 조건을 알기 위해서 분산도를 조사하였다. 분산도는 혼합순서, 시간 및 온도 등의 많은 인자들에 의해 영향을 받는 것이 확인되었다. 가교시스템은 황 가교시스템, 과산화물 가교시스템, 가교밀도 및 구조 등의 관찰로 연구하였다. 접착제의 변화는 건조 상태와 hexamine 함량 등과 같은 것으로부터 NBR과 접착제 사이의 관계를 연구하였다. 이 결과 접착 물성과 가공성은 ACN 함량 및 가교시스템에 따라 차이를 보였다.

• 대한화학회지
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• 제41권5호
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• pp.234-238
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• 1997

산소가 제거된 메탄올수용액에서 암모니아의 광화학반응을 25$^{\circ}C$에서 184.9 nm의 자외선을 이용하여 연구하였다. 메탄올과 암모니아의 몰분율이 각각 0.10, $5{\times}10^{-4}$인 수용액의 빛 조사에서 아미노화반응이 진행되어 메톡시아민, 핵사민, 1,1-디메칠히드라진, 디메칠아민, 포름아미드 그리고 소량의 에칠렌디아민 등이 생성되었다. 또한 이러한 생성물 이외에 포름알데히드, 에칠렌글리콜 및 글리옥살 등의 카르보닐화합물들과 히드라진도 함께 생성되었다. 반응의 결과 얻어진 각 생성물들에 대한 초기 양자수득율을 결정하였으며, 이들 값으로부터 메탄올과 암모니아가 혼합된 수용액의 광반응에 대한 가능한 반응메카니즘을 제시하였다.

• 한국분말재료학회지
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• 제22권6호
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• pp.391-395
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• 2015

We report on the successful fabrication of ZnO nanorod (NR)/polystyrene (PS) nanosphere hybrid nanostructure by combining drop coating and hydrothermal methods. Especially, by adopting an atomic layer deposition method for seed layer formation, very uniform ZnO NR structure is grown on the complicated PS surfaces. By using zinc nitrate hexahydrate $[Zn(NO_3)_2{\cdot}6H_2O]$ and hexamine $[(CH_2)_6N_4]$ as sources for Zn and O in hydrothermal process, hexagonal shaped single crystal ZnO NRs are synthesized without dissolution of PS in hydrothermal solution. X-ray diffraction results show that the ZnO NRs are grown along c-axis with single crystalline structure and there is no trace of impurities or unintentionally formed intermetallic compounds. Photoluminescence spectrum measured at room temperature for the ZnO NRs on flat Si and PS show typical two emission bands, which are corresponding to the band-edge and deep level emissions in ZnO crystal. Based on these structural and optical investigations, we confirm that the ZnO NRs can be grown well even on the complicated PS surface morphology to form the chestnut-shaped hybrid nanostructures for the energy generation and storage applications.