• Toxicological Research
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• v.3 no.2
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• pp.89-96
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• 1987

To test the efficacies of thiosulfate in cyanide poisoning with or without oxygen, after the administration of sublethal dose of potassium cyanide, serial arterial blood samples were collected during 60 minutes in 15 rabbits. Cyanide ion concentrations were measured by Conway cell microdiffusion method, and arterial oxygen tensions were also observed. Comparison of elimination constants showed that arterial blood cyanide ion concentration decreased most rapidly in the thiosulfate with oxygen-administered group. The elimination of cyanide ion by the action of thiosulfate in acutely poisoned rabbit accelerated probably due to oxygen and elimination pattern seems to occur by first-order elimination kinetics.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3696-3700
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• 2012

The colorimetric and fluorescent cyanide recognition properties of 2-[(9-ethyl-9H-carbazol-3-yl)methylene]-propanedinitrile (1) in $CH_3CN-H_2O$ (2/1, v/v, HEPES 10 mM, pH = 7.0) solution were evaluated. The optical recognition process of probe 1 exhibited high sensitivity and selectivity to cyanide ion with the detection limit of $2.04{\times}10^{-6}$ M and barely interfered by other coexisting anions. The sensing mechanism of probe 1 is speculated to undergo a nucleophilic addition of cyanide to dicyanovinyl group present in compound 1. The colorimetric and fluorescent dual-modal response to cyanide makes probe 1 has a potential utility in cyanide detection.

• Journal of the Korean Chemical Society
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• v.18 no.6
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• pp.423-429
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• 1974

The rate constant of the addition of hydrogen cyanide to $ ${\alpha}$-cyano-\beta-piperonylacrylic$ acid (CPA) were determined by UV spectrophotometry at various pH and a rate equation which can be applied over wide pH range was obtained. From this equation, one may conclude that below pH 3 the reaction is started by the addition of hydrogen cyanide molecule to CPA, however, at pH 6~8, hydrogen cyanide is added to $ {\alpha}$-cyano-$ {\beta}$-piperonyl acrylate anion. From pH 3 to 6, these two reaction are competitive. Above pH 9, the reaction is proceeded by the addition of cyanide ion to $ {\alpha}$-cyano-$ {\beta}$-piperonyl acrylate ion. From pH 3 to 9, the complex reaction mechanism can also be fully explained by the rate equation obtained.

• Journal of the Mineralogical Society of Korea
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• v.28 no.1
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• pp.29-38
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• 2015

Cyanide can be leached out from the cyanidation method which has been used to extract high-purity gold and silver from ores, and it becomes a variety of cyanide complexes associated with heavy metals contained in ores. Such cyanide complexes are considered as persistent and non-degradable pollutants which cause adverse effects on humans and surrounding environments. Based on binding force between heavy metals and cyanide, cyanide complexes can be categorized weak acid dissociable (WAD) and strong acid dissociable (SAD). This study comparatively evaluated the performance of photo-catalytic process with regard to forms of cyanide complexes. In particular, both effects of UV LED wavelength and surface modification of photo-catalyst on the removal efficiency of cyanide complexes were investigated in detail. The results indicate that the performance of photo-catalytic oxidation is significantly affected by the form of cyanide complexes. In addition, the effect of UV LED wavelength on the removal efficiency was quite different between free cyanide and cyanide complexes associated with heavy metals. The results support that the surface modification of photo-catalyst, such as doping can improve overall performance of photo-catalytic oxidation of cyanide complexes.

• Clean Technology
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• v.27 no.2
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• pp.168-173
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• 2021

The treatment of plated wastewater is subject to various and complex processes depending on the pH, heavy metal, and cyanide content of the wastewater. Alkali chlorine treatment using NaOCl is commonly used for cyanide treatment. However, if ammonia and cyanide are present simultaneously, NaOCl is consumed excessively to treat ammonia. To solve this problem, this study investigated 1) the consumption of NaOCl according to ammonia concentration in the alkaline chlorine method and 2) whether ferrate (VI) could selectively treat the cyanide. Experiments using simulated wastewater showed that the higher the ammonia concentration, the lower the cyanide removal rate, and the linear increase in NaOCl consumption according to the ammonia concentration. Removal of cyanide using ferrate (VI) confirmed the removal of cyanide regardless of ammonia concentration. Moreover, the removal rate of ammonia was low, so it was confirmed that the ferrate (VI) selectively eliminated the cyanide. The cyanide removal efficiency of ferrate (VI) was higher with lower pH and showed more than 99% regardless of the ferrate (VI) injection amount. The actual application to plated wastewater showed a high removal ratio of over 99% when the input mole ratio of ferrate (VI) and cyanide was 1:1, consistent with the molarity of the stoichiometry reaction method, which selectively removes cyanide from actual wastewater containing ammonia and other pollutants like the result of simulated wastewater.

• Toxicological Research
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• v.28 no.3
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• pp.195-199
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• 2012

The records of 255 cyanide poisoning deaths obtained from National Forensic Service (NFS) headquarters, located in Seoul of Korea, from 2005 to 2010 were retrospectively reviewed. The mean age was $41.88{\pm}13.09$ and range was 6~80 years (unknown in seven cases). The number of deaths of males and females were 200 and 53, respectively (unknown in two cases). The largest number of cases occurred in people aged 40-49 years (81 cases, 31.8%), followed by the age groups 30~39 years (51 cases, 20%), 50~59 years (44 cases, 17.2%) and 20~29 years (43 cases, 16.9%). The total number of deaths among other age groups (below 10, 10~19, 60~69, 70~79, over 80 years and unknown) were 36, representing only 14.1%. Of all cyanide poisoning deaths, 97.3% were due to suicide, and 14.5% of the total number who died received medical treatment. The most frequent site for ingestion was the person's own residence (120 cases, 47.1%) and the route of administration was mainly oral (252, 98.8%). From the total of 255 cyanide poisoning cases, white powders were submitted for analysis in 92 cases. Potassium cyanide and sodium cyanide occupied 51 and 41 cases, respectively. This study showed that poisoning deaths due to cyanide are one of the continuously reported public health problems in Korea. Enforcement of regulations and safety education to prevent cyanide poisoning should be carried out by the government.

• Resources Recycling
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• v.24 no.4
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• pp.61-66
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• 2015

Cyanidation has been used worldwide to recover gold from primary ore or concentrate. The use of cyanide is however becoming an emerging issue because of the toxic residue and wastewater made from the process. The cyanide-containing wastewater should be treated properly, obeying the environmental standard and regulations. In the present article, the domestic and international uses, regulations, and treatment technologies of cyanide in gold mining were investigated as a feasibility study to develop a cyanide treatment process as well as the cyanidation process. A biological cyanide treatment process to develop a zeroemission gold recovery and wastewater treatment process was also briefly introduced.

• Journal of Oral Medicine and Pain
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• v.8 no.1
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• pp.83-96
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• 1983

The purpose of this study was detection of the poison from the acute cyanide and aresenic poisoned rabbits, The author administered KCN and $AS_2O_3$ to rabbits and caused acute poisoning, then analysed the teeth, dental pulp and jaws of the rabbits chemicotoxicologically and observed the specimen histopathologically. 1. In subcutaneausly injected group of KCN, a large amount of cyanide was detected in blood and lung and a small amount of cyanide was detected in teeth and dental pulp, but was not detected in jaws. 2. In orally administered group of KCN a large amount of cyanide was detected in blood, lung and dental pulp and a small amount of cyanide was detected in teeth and jaws. 3. In orally administered group of $AS_2O_3$, arsenic was detected markedly in teeth and jaws, but was detected a little in dental pulp. 4. In orally administered and heat-treated group of KCN, the author could detected cyanide in teeth, dental pulp and jaws. 5. In suvcutanelusly injected group of KCN, orally administered group of KCN and orally dministered group of $AS_2O_3$, histopathologic findings showed the congestion and hemorrhage in dental pulp. 6. In orally administerd group of $AS_2O_3$, the congestion and hemorrhage in buccal mucosa were found and the basal cell degeneration and fibrosis were found in palatal mucosa.

• Journal of Environmental Science International
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• v.17 no.11
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• pp.1221-1226
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• 2008

A variety of fungal species are known to degrade cyanide through the action of cyanide hydratase, a specialized nitrilases which hydrolyze cyanide to formamide. This work is a report on two unknown and un-characterized members from Neurospora crassa and Aspergillus nidulans. Recombinant forms of three cyanide hydratases (CHT) originated from N. crassa, Gibberella zeae, and A. nidulans were prepared after their genes were cloned with N-terminal hexahistidine purification tags, expressed in E. coli and purified using immobilized metal affinity chromatography. These enzymes were compared according to their pH activity profiles, and kinetic parameters. Although all three were similar, the N. crassa CHT has the widest pH range of activity above 50% and highest turnover rate ($6.6{\times}10^8min^{-1}$) among them. The CHT of A. nidulans has the highest Km value of the three nitrilases evaluated in here. Expression of CHT in both N. crassa and A. nidulans were induced by the presence of KCN, regardless of any presence of nitrogen sources. These data can be used to determine optimal procedures for the enzyme uses in the remediation of cyanide-containing wastes.

• Environmental Engineering Research
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• v.23 no.2
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• pp.223-227
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• 2018

This study reports a cyanide resistant and/or tolerant fungus, isolated from the rhizosphere of Zea mays contaminated with cyanide-based pesticides. The isolate was characterised using molecular biology. The effect of free cyanide and heavy metals on the growth of isolate in a synthetic gold mine wastewater was examined. The molecular analyses identified the isolate as Fusarium oxysporum EKT01/02 (KU985430/KU985431). The isolate had a free cyanide degradation efficiency of 77.6%. The results indicated greater growth impairment in culture containing Arsenic (optical density 1.28 and 1.458) and cyanide (optical density 1.315 and 1.385). Higher growth was observed in all cultures supplemented with extracellular polymeric substance. This study showed that the isolate possesses wide substrate utilisation mechanism that could be deployed in environmental engineering applications.