• Resources Recycling
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• v.17 no.1
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• pp.38-42
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• 2008

This study was carried out to investigate the solubility of vanadium in ammoniacal solution and precipitation of $NH_4VO_3$ as a function of temperature and addition of ammonia salt. Higher solution temperature is required to get high solubility of vanadium and the vanadium concentration of solution was 16.8g/L at $90^{\circ}C$ with the solution of 20 g/L $(NH_4)_2CO_3$ and 2.5M $NH_4OH$. From this solution, vanadium could be precipitated up to 99.8% with adding 20 g/L $NH_4Cl$, 72 hours settling time at $25^{\circ}C$.

• Atmosphere
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• v.27 no.1
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• pp.29-40
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• 2017

The $PM_{10}$ and $PM_{2.5}$ particles over the Yellow Sea of Korea were collected by ship-borne observation during two cruises in spring, 2015. Their water-soluble ionic components such as $NH_4^+$, $Na^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $SO_4^{2-}$, $NO_3^-$, $Cl^-$, $F^-$, $CH_3COO^-$, $HCOO^-$, and $CH_3SO_3^-$ were analyzed, in order to examine the pollution characteristics of the secondary aerosol components. The comparative study of particle size distribution has resulted that $NH_4^+$, $nss-SO_4^{2-}$, $nss-Mg2+$, $nss-K^+$, $HCOO^-$, and $CH_3SO_3^-$ species mostly existed in fine particle mode. Meanwhile, nss-F-and sea-salt species were distributed in both fine and coarse particle mode, $NO_3^-$, $nss-Ca^{2+}$, $CH_3COO^-$ species were rich in coarse particle mode. The concentrations of secondary pollutants($nss-SO_4^{2-}$, $NO_3^-$, $NH_4^+$) increased in fine particles, and those of natural components ($nss-Ca^{2+}$, Sea-salt) increased in coarse particles. $NH_4^+$ exists as the form of $(NH_4)_2SO_4$ and $NH_4NO_3$, and mostly as $(NH_4)_2SO_4$ in fine particles. $NH_4NO_3$ has lower content compared to $(NH_4)_2SO_4$, and it mostly existed in fine particles at Yellow Sea I and in coarse particles at Yellow Sea II. The concentration ratios of $NO_3^-/nss-SO_4^{2-}$ for Yellow Sea I and Yellow Sea II were 0.52 and 0.16 in coarse particles, and they were 0.64 and 0.38 in fine particles, respectively, showing that the stationary source emissions were more important than mobile source emissions in Yellow Sea II (except Passage II-4).

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.503-506
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• 2008

질소제거 능력이 있는 Pseudomonas aeruginosa을 고분자물질인 PEG 에 포괄고정화하였으며 제조된 고정화 미생물을 이용하여 질소제거에 미치는 C/N비, 농도, 충진율, 탄소별 제거율을 검토한 결과 다음과 같은 결론을 얻었다. 1) C/N비 10이상이면 NH$_4$-N 와 NO$_3$-N의 동시 제거가 가능하였으며 2) 탄소 원으로는 glucose를 사용하였을 때 NH$_4$-N 와 NO$_3$-N의 동시 제거가 가능하였으나 methanol은 탄소원으로 사용할 수 없었다. 3) 저농도의 NO$_3$-N(50 mg/L)는 완전히 제거 가능하였으나 NH$_5$-N인 경우에는 초기 NH$_4$-N 100 mg/L에서 60%정도만 제거되었다. 4) 연속처리 결과 NH$_4$-N는 HRT 변동에도 불구하고 유출수 농도 변화가 거의 없었으나, 오히려 C/N비를 증가시키면 NH$_4$-N 제거 효율이 높았고, NO$_3$-N인 경우도 마찬가지로 C/N비를 증가시키면 NO$_3$-N 제거 효율이 높았다.

• Journal of the Korean Ceramic Society
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• v.45 no.1
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• pp.30-35
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• 2008

In this paper, CdS/Cd(Cu)S thin films and diodes were manufactured via a chemical bath deposition (CBD) process, and the effects of $NH_4Cl$ and TEA(triethylamine) on the properties of the films were examined. The addition of $NH_4Cl$ significantly increased the thickness of the CdS and Cd(Cu)S films, however, the addition of TEA decreased the thickness in both cases slightly. The addition of $NH_4Cl$ along with TEA increased the film thickness more effectively compared to the addition of only $NH_4Cl$. The thickness of the CdS film prepared from an aqueous solution of 0.007 M $CdSO_4$, 1.3 M $NH_4OH$, 0.03 M $SC(NH_2)_2$, 0.0001 M TEA and 0.03 M $NH_4Cl$ was 310 nm. Dark resistivity of the CdS film was $1.2{\times}10^3\;{\Omega}cm$ and the photo resistivity with $500\;W/cm^2$ irradiation of white light was $20{\Omega}cm$. The Cd(Cu)S/CdS thin film diodes prepared by CBD showed good rectifying characteristics.

• Journal of Korean Society on Water Environment
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• v.22 no.3
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• pp.482-491
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• 2006

The anaerobic ammonium oxidation (ANAMMOX) from substrates with various $NO_2-N$ and $NH_4-N$ concentationes, which were generated from piggery waste was accomplished by using anaerobic granular sludge as seeding sludge. As the result of operation, when $NO_2-N/NH_4-N$ ratios of ANAMMOX influent were 0.6~1.5, $NO_2-N/NH_4-N$ removal ratios were exhibited 1.19~2.07 (average 1.63). The higher influent $NO_2-N/NH_4-N$ ratios resulted in higher $NO_2-N/NH_4-N$ removal ratios by ANAMMOX. It means that $NO_2-N$ concentration is very important factor in ANAMMOX. Specific ammonium removal rate was constantly as $0.03{\sim}0.04gNH_4-N/g$ VSS-day at $35^{\circ}C$ while it was $0.01gNH_4-N/g$ VSS-day at $20{\sim}30^{\circ}C$. Thus, in order to reduce the effluent N concentration, either an increase of ANAMMOX reactor HRT or more biomass accumulation at the optimal temperature can be considered.

• Horticultural Science & Technology
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• v.34 no.5
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• pp.727-735
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• 2016

This research was conducted to investigate the influence of various pre-planting $NO_3:NH_4$ ratios in the coir dust+peatmoss+perlite (3.5:3.5:3, v/v/v) medium on the growth of tomato plug seedlings (cv. Dotaerang Dia), changes in chemical properties of root media, and tissue nutrient contents. With the fixation of N concentration to $300mg{\cdot}L^{-1}$, the $NO_3:NH_4$ ratios were adjusted to 100:0, 73:27, 50:50, 27:73, 0:100. Then, root media containing various $NO_3:NH_4$ ratios and equal concentration of other essential nutrients were filled into 50-cell plug trays and the seeds of 'Dotaerang Die' tomato were sown. The investigation of seedling growth and tissue analysis for mineral nutrient contents based on the dry weight of above-ground tissue were conducted 6 weeks after sowing. As seedlings grew, the EC decreased quickly and pH increased gradually in the all treatment media. The plant height, fresh weight and dry weight of seedlings in the treatment of 50:50 ($NO_3:NH_4$) were 29.0 cm, 13.7 g, and 1.21 g, respectively, which were the highest among treatments tested. However, the seedlings in the treatment of 0:100 ($NO_3:NH_4$) had 26.5 cm, 11.2 g, and 0.92 g in plant height, fresh weight and dry weight, respectively. These were the poorest among the treatments tested. The tissue contents of N were 2.77 to 3.22% in all the treatments. The treatment of 27:73 ($NO_3:NH_4$) had the highest contents of Fe, Mn and Zn and that of 0:100 ($NO_3:NH_4$) had the lowest contents of Mg, Na, Cu, Mn and Zn among the treatments tested. The results indicate that $NH_4$ ratio should be lower than 50% in the coir dust+peatmoss+perlite (3.5:3.5:3, v/v/v) medium for seedling growth of tomato and the optimum ratio will be used to draw up guide lines for plug seedling production.

• YAKHAK HOEJI
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• v.5 no.1
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• pp.16-19
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• 1960

Quantitative determination of Arsenic acid by precipitation of Arsenic acid as ZnNH$_{4}$AsO$_{4}$ and titration of Zn in the precipitate by EDTA has been investigated. Conclusion are as follows; 1) ZnNH$_{4}$AsO$_{4}$ was Soluble in NH$_{4}$Cl-NH$_{4}$OH buffer solution of pH lo and back-titration was unnecessary as in the case of MGNH$_{4}$AsO$_{4}$. 2) The end point was clear whether AsO$_{4}$$^{-3}$ present or not. 3) More simple and rapid method than that of Gravi metric method. 4) Could be determined within 0.3% error.

• YAKHAK HOEJI
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• v.7 no.4
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• pp.98-99
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• 1963

Compound III and IV were formed from I and II with $NH_{2}(CH_{2})_{3}NH_{2}$ respectively. Reduction of I with $LiAlH_{4}$ bollowed by $PoCl_{3}$ treatment affored VIII. Compound VI which was asumed by IR-data were obtained by treatment of $NH_{2}NH_{2}$ upon I or V.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.65-71
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• 2013

This research was conducted to evaluate the influence of $NO_3{^-}:NH_4{^+}$ ratios in fertilizer solution on the vegetative growth and fruit yield of hot pepper (Capsicum annuum L.) through pot cultivation. The Hoaglad's solution was modified to contain various $NO_3{^-}:NH_4{^+}$ ratios such as 100:0 (A), 73:37 (B), 50:50 (C), 27:73 (D), 0:100 (E), and no nitrogen (F). Plants were transplanted into root substrates and the modified solutions were applied as plant needed in plastic house. There were no statistical significances among the treatments from A through D in the fresh and dry weights, and number of leaves 31 days after transplanting, but elevation of $NH_4{^+}$ ratios in the solution decreased the fresh fruit weight 62 days after transplanting with statistical differences. In the results of inorganic element analysis based on the dry weight of fully expanded mature leaves, N and P contents as well as micro cations such as Fe, Mn, Zn, and Cu increased as $NH_4{^+}$ ratios were elevated 62 days after transplanting. However, those of macro cations such as K, Ca, and Mg resulted in decreasing tendency. The elevation of $NH_4{^+}$ ratios in fertilizer solution resulted in the increase of EC and total N concentrations ($NO_3{^-}+NH_4{^+}$), but this decreased the pH as well as Ca and Mg concentrations in soil solution 62 days after transplanting. The K concentration in soil solution was the highest in the treatments of C and followed by D, B, E, and A. The above results indicate that the proper $NO_3{^-}:NH_4{^+}$ ratio in the nutrient solution is 73:27 (B) or 100:0 (A) and the B solution is proper for the vegetative growth and that of A is proper for reproductive growth stage.

• Journal of Bio-Environment Control
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• v.28 no.2
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• pp.110-116
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• 2019

This study was conducted to determine the effects of a pre-planting fertilizers with various $NH_4{^+}:NO_3{^-}$ ratios in a coir dust:peatmoss:perlite (3.5:3.5:3.0, v/v/v) medium on the growth of hot pepper (Capsicum annuum L. cv. Nokkwang) plug seedling. Nitrogen levels were fixed to $300mg{\cdot}L^{-1}$ and the $NH_4{^+}:NO_3{^-}$ ratios were varied to 0:100, 27:73, 50:50, 73:27, and 100:0. The 50-cell trays were filled with treatment media containing pre-plant fertilizers, then seeds were sown. After seeds were germinated, the trays were moved to greenhouse and seedlings were feed with 13-2-13 and 20-9-20 fertilizers, alternatively. The changes in pH and EC were measured every week and soil solution for nutrient concentrations were analyzed in week 0, 3, and 7. The measurements of seedling growths as well as analysis of tissue nutrient contents were also conducted in week 7. The varied $NH_4{^+}:NO_3{^-}$ ratios did not influence on the pHs of root media after incorporation of pre-planting fertilizers, but the ECs were heightened as proportion of $NH_4{^+}$ to $NO_3{^-}$ were elevated. During the raising of seedlings, the pHs rose over time in the treatments of 0:100 and 27:73 ($NH_4{^+}:NO_3{^-}$). The concentrations of all macro-elements in root media decreased gradually as seedlings grew in all treatments. The seedling growths 7 weeks after seed sowing were the highest in the treatments of 27:73 and 50:50 ($NH_4{^+}:NO_3{^-}$) and those became worse in the treatments of higher $NH_4{^+}$ ratios than 73%. In terms of inorganic element contents based on the dry weight of above ground tissue, the treatment of 0:100 showed the lowest content of Ca, Mg, Na, Cu, Mn, and Zn. Based on the results, it is desired that $NH_4{^+}$ ratio in pre-planting fertilization is maintained to be 50% or less for the raising of hot pepper plug seedlings.