• Analytical Science and Technology
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• v.18 no.5
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• pp.381-385
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• 2005

The title compound, $\{H_2NCH_2CH_2NH_2CH_2CH_2\}\{Cu(H_2O)_6\}(SO_4)_2$, I, has been synthesized under solvo/hydrothermal conditions and their crystal structure analyzed by X-ray single crystallography. Compound I crystallizes in the monoclinic system, $P2_1/n$ space group with a = 6.852(1), b = 10.160(2), $c=11.893(1){\AA}$, ${\beta}=92.928(8)^{\circ}$, $V=826.9(2){\AA}^3$, Z = 2, $D_x=1.815g/cm^3$, $R_1=0.031$ and ${\omega}R_2=0.084$. The crystal structure of the piperazine templated Cu(II)-sulfate demonstrate zero-dimensional compound constituted by doubly protonated piperazine cations, hexahydrated copper cations and sulfate anions. The central Cu atom has a elongated octahedral coordination geometry. The crystal structure is stabilized by three-dimensional networks of the intermolecular $O_{water}-H{\cdots}O_{sulfate}$ and $N_{pip}-H{\cdots}O_{sulfate}$ hydrogen bonds between the water molecules and sulfate anions and protonated piperazine cations. Based on the results of thermal analysis, the thermal decomposition reaction of compound I was analyzed to have three distinctive stages.

• Korean Journal of Environmental Agriculture
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• v.20 no.5
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• pp.352-357
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• 2001

Cadmium (Cd) has been identified as a potential contaminant in agricultural and environmental soils. Ionic condition in the soils is an important factor to influence Cd availability. In this study, the effect of sulfate or nitrate application on Cd sorption in acidic and calcareous soils was investigated. The Cd, sulfate $(SO_4)$, and nitrate $(NO_3)$ sources were solutions of $CdCl_2$, $K_2SO_4$, and $KNO_3$, respectively. The soil-solution system pH was affected by the application of sulfate or nitrate in both acidic and calcareous soil system, but there was not clear pH difference between pre- and simultaneous applications of sulfate or nitrate (PAS/PAN or SAS/SAN). Solution ionic strength (I) values were similar between the acid and calcareous soil systems after applying the Cd even though it was significantly different in the untreated control soils. However after applying the sulfate or nitrate, the I values increased and were always higher with SAS/SAN treatments. Solution Cd concentration also increased with the application of sulfate or nitrate. However, the Cd concentration in soil solution controlled by Cd sorption in the systems was different between PAS/PAN and SAS/SAN treatments only in the calcareous soil system, but not in the acidic soil system. The difference in Cd concentration between SAS/SAN and PAS/PAN in the calcareous systems may be caused by system pH, ionic strength, complexation, and predominately, competition of the $Cd^{2-}$ with the index $K^+$ ion. Potassium ion-Cd competition in the acidic soil system may be minimized because of the abundance of hydrogen ions.

• Analytical Science and Technology
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• v.19 no.4
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• pp.309-315
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• 2006

Two piperazine-templated metal sulfate complexes, $(C_4N_2H_{12})[Ni(H_2O)_6](SO_4)_2$, I and ($C_4N_2H_{12}$) $[Co(H_2O)_6](SO_4)_2$, II, have been synthesized by hydro/solvothermal reactions and their crystal structures analyzed by single crystal X-ray diffraction methods. Complex I crystallizes in the monoclinic system, $P2_1/n$ space group, a=12.920(3), b=10.616(2), $c=13.303(2){\AA}$, ${\beta}=114.09(1)^{\circ}$, Z=4, $R_1=0.030$ for 3683 reflections; II: monoclinic $P2_1/n$, a=12.906(3), b=10.711(2), $c=13.303(2){\AA}$, ${\beta}=114.10(2)^{\circ}$, Z=4, $R_1=0.032$ for 4010 reflections. The crystal structures of the piperazine-templated metal(II) sulfates demonstrate zero-dimensional compound constituted by diprotonated piperazine cations, metal(II) cations and sulfate anions. The structures of complex I and II are substantially isostructural to that of the previously reported our piperazine-templated copper(II) sulfate complex $(C_4N_2H_{12})[Cu(H_2O)_6](SO_4)_2$. The central metal(II) atoms are coordinated by six water molecules in the octahedral geometry. The crystal structures are stabilized by three-dimensional networks of the $O_{water}-H{\cdots}O_{sulfate}$ and $N_{pip}-H{\cdots}O_{sulfate}$ hydrogen bonds between the water molecules and sulfate anions and protonated piperazine cations. Based on the results of thermal analysis, the thermal decomposition reactions of the complex I was analyzed to have three distinctive stages whereas the complex II proceed through several stages.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4B
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• pp.377-382
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• 2011

In this study, hydrogen peroxide is stabilized in modified Fenton reaction to improve the soil remediation. Phenanthrene, which is the typical compound in PAHs, was spiked into soil samples to copy the original contaminated site. Anionic surfactant, SDS (Sodium dodecyl sulfate) was used for hydrogen peroxide stabilizer. 4 mM of Fe(II), 5~50 mM of SDS and 102.897 mM of $H_2O_2$ was injected into soil samples which is contaminated by 125 mg/kg of phenanthrene to analyze decomposition rate of phenanthrene in modified Fenton reaction. In condition which SDS was injected 30 mM, decomposition rate of phenanthrene has best efficiency as 95% and in condition which SDS was injected over 30 mM, decomposition rate is lower than SDS 30 mM because SDS enacted as scavenger in the system. Results which assess the change of hydrogen peroxide concentration after injecting hydrogen peroxide stabilizer showed that hydrogen peroxide concentration was 14.6995 mM so that is stabilized at Fe(II) 2 mM condition in 48 hours. On the other hand, hydrogen peroxide is not stable in Fe(III) condition. SDS concentration was fixed and iron concentration was changed 2~8 mM to find out optimize proportion between iron concentration and SDS concentration in modified Fenton reaction. Consequentially, in condition of which Fe(II) 4 mM and SDS 30 mM, reaction has the highest removal rate as 95%.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.4
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• pp.371-378
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• 2006

Effect of $(NH_4)_2SO_4$ precipitation and heat-treatment on hydrogenase which was extracted from the cytoplasmic fraction of the phototrophic purple sulfur bacterium Thiocapsa roseopersicina NCIB 8347 was studied. Crude enzyme extract was prepared by centrifugation($28,000{\times}g$, $400,000{\times}g$) after sonication of cells grown under photosynthetic condition for 96 hrs. Various conditions of $(NH_4)_2SO_4$ precipitation and heat-treatment were examined and the effect of protein concentration was analyzed by SDS-electrophoresis between the treatments. Optimum conditions for $(NH_4)_2SO_4$ precipitation and heat-treatment for evolution hydrogenase activity were 40-60% saturation and $60^{\circ}C$ for 20 min, respectively, which exhibited the specific hydrogenase activity of 0.78 U/mg-protein. Specific hydrogenase activity was decreased to 31.6% when the heat-treatment at $60^{\circ}C$ increased from 20 min to 5 hrs.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.2
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• pp.64-72
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• 2004

We measured the vertical profiles of $O_2$, H$_2$S, and pH in sediment pore water beneath marine cage fish farms using a microsensor with a 25 ${\mu}{\textrm}{m}$ sensor tip size. The sediments are characterized by high organic material load. The oxygen consumption, hydrogen sulfide oxidation, and sulfate reduction rates in the microzonations (derived from the vertical distribution of chemical species concentration) were estimated by adapting a simple one-dimensional diffusion-reaction model. The oxygen penetration depth was 0.75 mm. The oxic microzonations were divided into upper and lower layers. Due to hydrogen sulfide oxidation within the oxic zone, the oxygen consumption rate was higher in the lower layer. The total oxygen consumption rate integrated with reaction zone depth was estimated to be 0.092 $\mu$mol $O_2$cm$^{-2}$ hr$^{-1}$ . The total hydrogen sulfide oxidation rate occurring within 0.7 mm thickness was estimated to be 0.030 $\mu$mo1 H$_2$S cm$^{-2}$ hr$^{-1}$ , and its turnover time in the oxic sediment layer was estimated to be about 2 minutes. This suggests that hydrogen sulfide was oxidized by both chemical and microbial processes in this zone. The molar consumption ratio, calculated to be 0.84, indicates that either other electron accepters exit on hydrogen sulfide oxidation, or elemental sulfur precipitation occurs near the $O_2$- H$_2$S interface. Total sulfate reduction flux was estimated to be 0.029 $\mu$mol cm$^{-2}$ hr$^{-1}$ , which accounted for more than 60% of total $O_2$ consumption flux. This result implied that the degradation of organic matter in the anoxic layer was larger than in the oxic layer.

• Journal of Powder Materials
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• v.4 no.2
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• pp.106-112
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• 1997

$Cu-Al_20_3 $ composite powders were prepared by hydrogen reduction of $Cu^{2+}$ from ammoniacal copper sulfate solution on alumina core using autoclave. The copper reduction rate and the properties of copper layer were investigated using Scanning Electron Microscope(SEM), X-ray diffractometer, size and chemical analyzers. The reduction rate of $Cu^{2+}$ showed the maximum value when the molar ratio of [$NH_3$]/[$Cu^{2+}$] was 2. In order to prevent the agglomeration of Cu powder and ethane reduction rate, $Fe^{2+}$ and anthraquinone which act as catalysis were added in the solution. Catalysis was effectively chanced with the addition of two elemerts at a time. Optimum conditions obtained in this study were hydrogen reduction temperature of 205$^{\cire}C$, stirring speed of 500 rpm and hydrogen partial pressure of 300 psi. Obtained $Cu-Al_20_3 $ composite Powders were found to have the uniform and continuous copper coating layer of nodule shape with 3~5 $\mu$m thickness.

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.320-324
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• 2007

The removal of hydrogen sulfide ($H_2S$) from aqueous media was investigated using Thiobacillus novellas cells immobilized on a $SiO_2$ carrier (biosand). The optimal growth conditions for the bacterial strain were $30^{\circ}C$ and initial pH of 7.0. The main product of hydrogen sulfide oxidation by T. novellus was identified as the sulfate ion. A removal efficiency of 98% was maintained in the three-phase fluidized-bed reactor, whereas the efficiency was reduced to 90% for the two-phase fluidized-bed reactor and 68% for the two-phase reactor without cells. The maximum gas removal capacity for the system was 254 g $H_2S/m^3/h$ when the inlet $H_2S$ loading was $300g/m^3/h(1,500ppm)$. Stable operation of the immobilized reactor was possible for 20 days with the inlet $H_2S$ concentration held to 1,100 ppm. The fluidized bed bioreactor appeared to be an effective means for controlling hydrogen sulfide emissions.

• New & Renewable Energy
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• v.18 no.4
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• pp.1-11
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• 2022

Landfill gas (LFG) generation characteristics in a construction waste landfill zone (block E) and mixed landfill zone (block A) were analyzed. During the period from October 2018 to April 2022, a total of 936×10³ and 1,001×10³ tons of waste were disposed in block E and block A, respectively. Out of this, 27.1% and 55.6% were biodegradable waste in block E and block A, respectively. The landfill masses of the two blocks were converted to be comparable. Then, the biodegradable waste and organic carbon were estimated by element analysis, biodegradable carbon by biochemical methane potential experiment (DC), and sulfate ion by acid decomposition. Results showed that biodegradable waste, organic carbon, biodegradable carbon, and sulfate ions in block A were 2.1, 1.6, 5.2, and 0.4 times greater than those in block E, respectively. The amount of LFG generated by block A was 4.8 times greater than that by block E. The average concentrations of methane (CH₄) were 60.8% and 60.9% in block E and block A, respectively, which were unrelated to the nature of disposed waste. The average concentrations of hydrogen sulfide (H₂S) were significantly high in block E (4,489 ppm) and block A (8,478 ppm). As the DC/SO₄^2- of block E and block A were 0.35 and 4.56, respectively, increase in DC/SO₄^2- caused increase in not only the total amount but also the concentration of H₂S generated.

• KSBB Journal
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• v.9 no.3
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• pp.287-293
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• 1994

A bacterium isolated from waste coal mine water around Hawsun had an ability for the degradation of hydrogen sulfide. The isolate was identified as Thiobacillus sp. IW. on the basis of its morphological, physiological and chemotaxonomical characteristics. The optimum pH and temperature were 7 and $30^{\circ}C$, respectively. Growth occurred in a pH range of 3 to 9. Due to the sulfate accumulated in liquid medium, the pH decreased. As a consequence the cell growth was inhibited. Potasium nitrate and glutamic acid were utilized as a nitrogen source but urea and ammonium chloride not consumed. Denitrification occurred in a basal medium containing the glucose but did not in a basal medium containing the malate. The maximum specific growth rate of cell was 0.78h-1 and generation time was 0.9 hour. The cell productivity was 6.25mg/1$.$h and the isolate grew logarithmically up to 18 hour. These results indicate that the isolate can be a suitable bacterium responsible for degradation of hydrogen sulfide as malodorous compounds.