• Journal of Environmental Health Sciences
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• v.46 no.5
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• pp.495-503
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• 2020

Objective: This study aimed to compare the characteristics of humidifier disinfectant-like products (HD-like products) and humidifier disinfectant products (HD products) and introduce actual cases of the usage of HD-like products in hospitals based on an on-site investigation. Methods: The characteristics, chemical components, and usage of HD-like products (Hichlor or Biospot) and HD products (N-with) containing NaDCC (sodium dichloroisocyanurate) were compared. In the process of conducting the on-site investigation, four hospitals were identified as previously using HD-like products. Each on-site investigation to identify the use of HD-like products was composed of four parts: 1) hospital infection control guidelines, 2) manual for humidifiers in patient's rooms, 3) interviews with nursing staff, infection managers, and purchase managers, 4) searching on the product purchase system. Results: Although HD-like products (Hichlor and Biospot) and HD products (N-with) were sold for different usage purposes, they were all white-colored and coin-shaped foaming tablets with the same chemical component, NaDCC. The manual for using HD-like products and HD products was similar (inserting the tablet in a humidifier container with water). Among the four hospitals, one had used Hichlor in the same manner as HD (N-with) by inserting a tablet in 1L of water in a filled humidifier container and Biospot as a kind of detergent for humidifier container cleaning. Another two hospitals had used Biospot and/or Aniosyme as a kind of detergent for humidifier container cleaning. The other hospital had used unknown product in the same manner as N-with, so we thus assumed it was either an HD products (N-with) or HD-like products (Hichlor, Biospot). Conclusion: This study raises the possibility of the development of adverse health effects similar to exposure to an HD-products when exposed to an HD-like products and the possibility of further use in other medical institutions or multi-use facilities. Therefore, an expansion of the investigation is needed in order to confirm whether there have been similar cases in the past.

• Journal of the Korean Ceramic Society
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• v.35 no.2
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• pp.180-184
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• 1998

It was examined that the rheological behaviors of fly ash 70wt%-clay 30wt% slip in which nonplastic fly ash was a major component. We have systematically investigated the effects of deflocculant(Tetrasodium pyrophosphate ; Na4P2O7 nH2O Sodium silicate; Na2SiO3) and coagulant(CaSO4) on the rheological behavior of ash-clay slip. Ash-clay slip have been characterized on the basis of the time dependent rheology which was done out by the gel-curve test. Dispersion mechanism of ash-clay slip is the steric stabilization by the Na2SiO3 coating of cenospheres surface. Coagulated slip seems to have the new network structure and shows the gellation behaviors which makes it possible to direct coagulated casting(DCC).

• Research in Plant Disease
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• v.20 no.2
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• pp.79-86
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• 2014

In order to seek more eco-friend, economic and safer quarantine method than current methyl bromide fumigation, the convergent treatment with 200 Gy of gamma irradiation and several chemicals such as nano-siver particles (NSS), sodium dichloroisocyanurate (NaDCC) was tried on the cuttings of lily in the packing of catonnage box for export. With 6 independent experiments of gamma irradiation on the three lily cultivars, cvs. Siberia, Le reve and Sorbonne, incidence and severity of lily leaf blight was investigated on leaves and petals at 8-d after infection. 200 Gy of gamma irradiation decreased at 13-25% of severity on the leaf of Sorbonne, but it increased at 2-5% of severity on the leaf of Siberia and Le reve. Chemical substitutes such as NSS and NaDCC were not effective to control of lily blight on cuttings. By 200 Gy of gamma irradiation treatment, chlorophyll contents were statistically significantly decreased at 12-d after irradiation and the longevities vaselife of fully open flower of Siberia and Sorbonne were increased at 0.4 to 1.2 days. In addition, the relative fresh weights of the gamma irradiated cuttings were severely dried compared to the non-irradiated control. On the other hands, the symptoms of phyto-toxicity of high dose gamma irradiation at 1 or 2 kGy on cv. Siberia were to be blight at the tip of bloom, bent necks of flower, and delayed the process of flowering.

• Food Science and Preservation
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• v.21 no.4
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• pp.468-472
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• 2014

The effect of pre-storage treatments was investigated to control the occurrence of fruit skin stain in 'Niitaka' pears. The incidence of fruit skin stains was significantly reduced when the fruits were stored in paper bags with a yellow inner color, compared to when they were stored in paper bags with blue and red inner colors. Additionally, the pear fruits that were harvested seven days earlier than their optimum maturity date developed less fruit skin stains in cold storage and retained their quality. Storage in polyethylene (PE) bags did not control the occurrence of fruit skin stains as effectively as did bag-free storage or storage in calcium-coated bags. The dipping of the pear fruits in a chlorine dioxide and calcium solution was highly effective in reducing the fruit skin stains compared to when they were not dipped or when they were dipped only in distilled water. In particular, a 1,500 times diluted solution of sodium dichloroisocyannurate (NaDCC) reduced the incidence of fruit skin stains and the size of the lesions. No stain was observed on the skin of the fruit with a water content lower than 67.7% (w/v) during its storage. In conclusion, packaging pear fruits in bags with an inner calcium coat and dipping them in a chlorine dioxide, calcium, or NaDCC solution can effectively reduce their skin stains during their storage.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.3
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• pp.74-80
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• 2009

The objective of this paper was to investigate the slip rate and the slip frequency number of damper clutch of torque converter in 2.4L passenger vehicle with 5-speed A/T and analyze the effect of slip control and control strategy on driving characteristics and the fuel economy. The newly developed torque converter with the more durable wet friction material and the slip-controlled damper clutch system, the DCC system, was installed, which was easily compatible and amendable of the lock-up clutch of the base system. The vehicle has been tested on the fuel economy modes such as FTP-75, HWFET and NEDC (ECE15+EUDC) driving cycle at chassis dynamometer. The DCC mode (II), of which the control strategy had both the lock-up and the slip-controlled clutch, and the DCC mode (I) with full slip-controlled clutch were compared with the base system with only the lock-up clutch. As the research result, comparison to base system, the fuel consumption of the vehicle with the DCC control (II) was effectively improved by 6.6% and 7.7% on FTP-75 and NEDC mode.

• Journal of the Korean Chemical Society
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• v.39 no.9
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• pp.749-754
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• 1995

The synthetic procedures to synthesize polymethacryloylsulfadiazine were searched by DCC method and Acid Chloride mothod. Polymeric drug was synthesized by Acid Chloride method in high yield (72%) but DCC method in low yield (23%). The antimicrobial activities of polymeric drug were investigated in terms of minimum inhibitory concentrations by the common two-fold dilution technique. Polymeric drug revealed an excellent antimicrobial Bacillus subtillis ATCC 6633, Mycrobacterium phlei IFO 3158, Micrococus luteus ATCC 9341, Salmonella typhimurium KCTC 1925, Klebsiella pneumoniae KCTC 1560 and similar activity against Staphylococcus aureus IFO 12732, Escherichia coli BE 1186, Escherichia coli AB 0111, Pseudomonas aeruginosa IFO 13130. Polymeric drug have no antimicrobial activity against Candida albicans IFO 1594.

• Journal of Microbiology and Biotechnology
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• v.27 no.12
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• pp.2141-2150
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• 2017

This study was conducted to develop a screening method using Colilert-18 and a device for the detection of E. coli from agri-food production environments and fresh vegetables. The specificity and sensitivity of Colilert-18 by temperature ($37^{\circ}C$ and $44^{\circ}C$) were evaluated with 38 E. coli and 78 non-E. coli strains. The false-positive rate was 3.8% (3/78) and 0% (0/78) at $37^{\circ}C$ and $44^{\circ}C$, respectively. The detection limit of E. coli at $37^{\circ}C$ at <1.0 log CFU/250 ml was lower than that at $44^{\circ}C$. The efficiency of the developed device, which comprised an incubator equipped with a UV lamp to detect E. coli in the field, was evaluated by measuring the temperature and UV lamp brightness. The difference between the set temperature and actual temperature of the developed device was about $1.0^{\circ}C$. When applying the developed method and device to various samples, including utensils, gloves, irrigation water, seeds, and vegetables, there were no differences in detection rates of E. coli compared with the Korean Food Code method. For sanitary disposal of culture samples after experiments, the sterilization effect of sodium dichloroisocyanurate (NaDCC) tablets was assessed for use as a substitute for an autoclave. The addition of one tablet of NaDCC per 50 ml was sufficient to kill E. coli cultured in Colilert-18. These results show that the developed protocol and device can efficiently detect E. coli from agri-food production environments and vegetables.

• The Korean Journal of Pesticide Science
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• v.20 no.1
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• pp.35-40
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• 2016

Recently, bacterial angular leaf spot disease, caused by Xanthomonas fragariae, causes severe damage in strawberry production and its' export to other countries, since the pathogen has been classified as an A2 quarantine pathogen. Typical the Angular Leaf Spot (ALS) disease represent that water-soaked angular spots symptoms, bacteria ooze exudate under relatively high humidity condition and later the spot become reddish brown on the leaf surface. The pathogen disseminated by irrigation water, infected mother plant and farmer's hand. In this study, we reported that rubbing inoculation method showed more effective in the pathogen dissemination than infiltration with needles, regardless the strawberry cultivars. Additionally, Dichloroisocyanurate (NaDCC) treatment in commercial strawberry fields provided reliable efficiency to reduce the bacterial angular leaf spot disease incidency and severity.

• Nuclear Engineering and Technology
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• v.36 no.6
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• pp.528-539
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• 2004

It is essential in commercial reactors that the safety limits imposed on the fuel pellets and fuel clad barriers, such as the linear power density (LPD) and the departure from nucleate boiling ratio (DNBR), are not violated during reactor operations. In order to accurately monitor the safety limits of current reactor states, a detailed three-dimensional (3D) core power distribution should be estimated from the in-core detector signals. In this paper, we propose a calculation methodology for detailed 3D core power distribution, using in-core detector signals and core monitoring constants such as the 3D Coupling Coefficients (3DCC), node power fraction, and pin-to-node factors. Also, the calculation method for several core safety parameters is introduced. The core monitoring constants for the real core state are promptly provided by the core design code and on-line MASTER (Multi-purpose Analyzer for Static and Transient Effects of Reactors), coupled with the core monitoring program. through the plant computer, core state variables, which include reactor thermal power, control rod bank position, boron concentration, inlet moderator temperature, and flow rate, are supplied as input data for MASTER. MASTER performs the core calculation based on the neutron balance equation and generates several core monitoring constants corresponding to the real core state in addition to the expected core power distribution. The accuracy of the developed method is verified through a comparison with the current CECOR method. Because in all the verification calculation cases the proposed method shows a more conservative value than the best estimated value and a less conservative one than the current CECOR and COLSS methods, it is also confirmed that this method secures a greater operating margin through the simulation of the YGN-3 Cycle-1 core from the viewpoint of the power peaking factor for the LPD and the pseudo hot pin axial power distribution for the DNBR calculation.

• Bulletin of the Korean Chemical Society
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• v.26 no.12
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• pp.2021-2026
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• 2005

The oxidation of cytidine 1 and inosine 5 by sodium metaperiodate followed by the reaction of the product with $CH_3I$ in NaOH afforded 2',4'-dihydroxyhexopyranosyl derivatives 2 and 14 respectively. The reaction of thiophene-2-carboxylic acid or furfural with cytidine were taken place via cycloaddition afforded adducts 3 and 4 respectivily. The bromination of inosine 5 or its 2',3'-O-isopropylidine inosine 6 led to the formation of 8-bromoanalogue 7 and 8, respectively. The reaction of 8-bromo-2',3'-O-isopropylidine inosine (8) with ethylglycinate hydrochloride afforded 8-ethoxycarbonylmethylaminoinosine 9. The alkylation of the compound 6 with urea led to the formation of 3-carbonylaminoinosine 10. The oxidation of 6 with DCC afforded 4'-formyl derivative 11, which on reaction with ethyl glycinate hydrochloride followed by reaction with sodium cyanoborohydride afforded 12, while the treatment of dialdehyde inosine 13 with ethyl cyanoacetate in the presence of 0.5 N NaOH afforded compound 15.