• 산업기술연구
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• 제24권B호
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• pp.65-71
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• 2004

The ultra fine gamma-alumina powder was prepared via ammonium aluminium carbonate hydroxide (AACH). The XRD, SEM, BET, thermal analysis were used to characterize the samples. The effects of various reaction parameters as concentration, of solution, anion on specific area, PH, aging time and thermal decomposition condition on the produced AACH and alumina were discussed.

• 한국세라믹학회지
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• 제43권4호
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• pp.242-246
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• 2006

[ ${\alpha}-Al_2O_3$ ] nanopowders were fabricated by the thermal decomposition and synthetic of Ammonium Aluminum Carbonate Hydroxide (AACH). Crystallite size of 5 to 8 nm were fabricated when reaction temperature of AACH was low, $8^{\circ}C$, and the highest $[NH_4{^+}][AlO(OH)_n{(SO_4){^-}}_{3-n/2}][HCO_3]$ ionic concentration to pH of the Ammonium Hydrogen Carbonate (AHC) aqueous solution was 10. The phase transformation fem $NH_4Al(SO_4)_2$, rhombohedral $(Al_2(SO_4)_3)$, amorphous-, ${\theta}-,\;{\alpha}-Al_2O_3$ was examined at each temperature according to the AACH. A Time-Temperature-Transformation (TTT) diagram for thermal decomposition in air was determined. Homogeneous, spherical nanopowders with a particle size of 70 nm were obtained by firing the 5 to 8 m crystallites, which had been synthesized from AACH at pH 10 and $8^{\circ}C,\;at\;1150^{\circ}C$ for 3 h in air.

• 한국분말재료학회지
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• 제14권2호
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• pp.145-149
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• 2007

Nanocrystalline transient aluminas (${\gamma}$-alumina) were coated on core particles (${\gamma}$-alumina) by a carbonate precipitation and thermal-assisted combustion, which is environmentally friend. The ammonium aluminum carbonate hydroxide (AACH) as a precursor for coating of transient aluminas was produced from precipitation reaction of ammonium aluminum sulfate and ammonium hydrogen carbonate. The crystalline size and morphology of the synthetic, AACH, were greatly dependent on pH and temperature. AACH with a size of 5 nm was coated on the core alumina particle at pH 9. whereas rod shape and large agglomerates were coated at pH 8 and 11, respectively. The AACH was tightly bonded coated on the core particle due to formation of surface complexes by the adsorption of carbonates, hydroxyl and ammonia groups on the surface of the core alumina powder. The synthetic precursor successfully converted to amorphous- and ${\gamma}$-alumina phase at low temperature through decomposition of surface complexes and thermal-assisted phase transformation.

• 자원리싸이클링
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• 제28권1호
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• pp.15-22
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• 2019

습식법으로 고순도 알루미나를 제조할 수 있는 알콕사이드 가수분해법, 암모늄 명반의 열분해법, 암모늄 알루미늄탄산염(AACH) 열분해법을 소개하였다. 상기 세 공정으로 알루미나 제조시 용액의 pH, 온도와 불순물이 알루미나의 상전이와 고순도에 미치는 영향을 조사했다. 알콕사이드와 암모늄 명반의 열분해법으로는 ${\alpha}$와 ${\gamma}$알루미나의 제조가 가능하다. 그러나 AACH 열분해법으로는 ${\gamma}$알루미나 제조는 어렵다.

• Journal of Plant Biology
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• 제8권3호
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• pp.4-8
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• 1965

Wir wollten beobachten, ob die Chlorophyllbnahme von Chlorella luteoviridis(211/2b) bei Glukose-Zugabe durch Stickstoffmangel hervorgerufen worden ist, wie viele Leute bei mineralsalzmangel(Aach (1952, Fogg 1956 Eyster et al (1958), oder Photooxydationschlorose (Kandler 1958) vermuteten. Chlorella luteoviridis bildete nicht Chlorophyll bei Glukosezugabe wie bei Autotrophkultur, obwohl Stickstoffsynthese bei Autotrophkultur stark gef rdert worden ist. Bei Nitratanzucht mit Glukose (Mixotroph) waren die Zellvermehrung und Kohlenhydratbildung nicht so stark wie bei der Glukoseanzucht mit NH4Cl2 trotzdem nahm Chlorophyll ab. Chlorella luteoviridis bildete Chlorophyll im Dunkeln und St rkeakkumulation erschien nicht bei Glukoseanzucht.

• 생약학회지
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• 제43권4호
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• pp.323-327
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• 2012

Acne, also known as Acne vulgaris, is a common disorder of human skin involving the sebaceous gland and Propionibacterium acnes (P. acnes). The purpose of this study was to demonstrate whether anti-acne herbal complex (AAHC), a functional extract from herbal complex can be used for acne treatment as a natural product. We first demonstrated anti-acne activity of AAHC in mouse acne model. Acne was induced by injecting P. acnes on the backside $2{\times}10^7$ CFUs in ICR mice and then the mice were treated with AAHC by dermal application once daily. ACFREE$^{(R)}$ (clindamicin phosphate) was used as a positive control. Treatment with AAHC decreased the P. acnes-induced skin swelling and inflammation. AAHC treatment significantly decreased serum DHT concentration in acne-induced mice. Especially, treatment of 20% AACH in mice was more effected than 40%. We next evaluated the antimicrobial property of AAHC against P. acnes, Staphylcococcus aureus (S.aureus), and Escherichia coli (E. coli). Incubation of P. acnes, S. aureus, and E. coli with AAHC showed minimal inhibitory concentration (MIC) values against the bacterial growth lower. Alamar blue method was also carried for the antibacterial activity. It was effectively MIC level at 6.25% of P. acnes. AAHC effectively inhibited the growth of S. aureus and E. coli at 0.097% on MIC level, respectively. Our results showed the potential of using AAHC as an alternative treatment for antibiotic therapy of acne and the application of AAHC as a herbal medicine for acne treatment.