• Journal of Industrial Technology
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• v.24 no.B
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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.

• Journal of the Korean Ceramic Society
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• v.43 no.4 s.287
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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.

• Journal of Powder Materials
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• v.14 no.2 s.61
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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.

• Resources Recycling
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• v.28 no.1
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• pp.15-22
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• 2019

There are three hydrometallurgical methods by which pure alumina can be prepared, such as hydrolysis of aluminum alkoxides, thermal decomposition of ammonium alum and thermal cracking of ammonium aluminum carbonate (AACH). The effect of solution pH and temperature and the nature of the impurities on the phase transition and the purity of the alumina thus produced was investigated. Hydrolysis of aluminum alkoxides and thermal decomposition of ammonium alum produce ${\alpha}$ and ${\gamma}$ alumina, while only ${\alpha}$ alumina can be produced by thermal cracking of AACH.

• Journal of Plant Biology
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• v.8 no.3
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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.

• Korean Journal of Pharmacognosy
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• v.43 no.4
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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.