• Title/Summary/Keyword: Sodium nitrate

Search Result 216, Processing Time 0.028 seconds

Effects of a mouthwash containing potassium nitrate, sodium fluoride, and cetylpyridinium chloride on dentin hypersensitivity: a randomized, double-blind, placebo-controlled study

  • Hong, Ji-Youn;Lim, Hyun-Chang;Herr, Yeek
    • Journal of Periodontal and Implant Science
    • /
    • v.46 no.1
    • /
    • pp.46-56
    • /
    • 2016
  • Purpose: We evaluated the efficacy of a mouthwash containing potassium nitrate ($KNO_3$) as its main component, along with sodium fluoride (NaF) and cetylpyridinium chloride (CPC). The primary endpoint was the relief of dentin hypersensitivity (DH) against the cold stimuli. The effects on other DH tests and periodontal inflammation were also evaluated. Methods: We used a single-center, double-blind, placebo-controlled, randomized design. A total of 82 patients with DH (40 in the test group, 42 placebo controls) were analyzed using visual analog scales (VASs) for a cold test, a tactile test, a compressive air test, and self-reported pain during daily activities, as well as clinical parameters including plaque index, gingival index, modified sulcular bleeding index (mSBI), gingival recession, and probing depth, which were collected at baseline and after four and six weeks of mouthwash use. Results: VAS scores for cold sensations, tactile sensations, the compressive air test, and self-reported pain significantly decreased from baseline during the six weeks in both groups (P<0.01), and no significant differences between the groups were found. In male patients (10 in the test group and 7 in the control group), both groups showed significant reductions in VAS scores for the cold test over the six weeks, and greater reductions were found in the test group than in the control group between four and six weeks (P=0.01) and between baseline and six weeks (P<0.01). In addition, the mSBI in the test group significantly decreased from baseline during the six weeks (P<0.01), and the changes at four and six weeks from baseline were significantly greater in the test group compared to the control group (P=0.03 and P=0.02, respectively). Conclusions: A mouthwash containing a mixture of $KNO_3$, NaF, and CPC reduced DH and gingival inflammation, however, the efficacy was comparable to the control group.

Process Development for Effective Denitrification by Biofilter Using Loess Ball

  • CHOI DU BOK;LEE DONG BYUNG;CHA WOL SUK
    • Journal of Microbiology and Biotechnology
    • /
    • v.15 no.2
    • /
    • pp.412-420
    • /
    • 2005
  • In order to investigate factors affecting the denitrification in the F-STEP PROCESS using a loess ball as support media and Pseudomonas DWC 17-8, calcining temperature, loess ball size, pH, nitrate concentration, working temperature, and inhibitor were studied in batch mode using synthetic sludge. A 5- 10 mm of loess ball (960$^{circ}$ of calcining temperature) was the most suitable for denitrification. When the initial pH was increased from 3.0 to 7.0, the removal efficiency of nitrate was increased. Specifically, at initial pH of 7.0, the maximum removal efficiency of nitrate was 5.0 mg/min. When the initial concentration of nitrate was increased from 100 to 400 mg/l, the removal efficiency of nitrate was proportional to the concentration of nitrate. The maximum removal efficiency of nitrate was 5.72 mg/min at 400 mg/l of initial concentration. When the operating temperature was increased from 10 to 30$^{circ}$, the removal efficiency of nitrate was increased from 0.76 to 6.15 mg/min, and at above 40$^{circ}$ of operating temperature, it was decreased from 4.0 to 2.0 mg/min. Among the various inhibitors, higher than 10$^{-1}$ M of sodium azide abolished this reaction completely. When the KCN concentration was above 10$^{-1}$ M, the reaction was inhibited completely. In the case of 2,4-dinitrophenol and sodium sulphide, it was inhibited at above 10$^{-2}$ M completely. For testing the various flow orders of the F-STEP PROCESS for effective denitrification using practical wastewater, continuous experiments under the optimum conditions were carried out for 60 days. Among the various processes, the PROCESS A gave the highest efficiencies of denitrification, nitrification, and total nitrogen (TN) removal with 86.5, 89.5, and $90\%$, respectively. For scale-up in the PROCESS A, real farm wastewater was used and pilot tests carried out for 90 days. The denitrification efficiency was $97.5\%$, which was increased by $12.7\%$. The efficiencies of TN removal and nitrification were 96.6 and $70.0\%$, respectively. The removal efficiency of chemical oxygen demand (COD) was $63.7\%$, which was increased by $20\%$.

Effect of Using Vegetable Powders as Nitrite/Nitrate Sources on the Physicochemical Characteristics of Cooked Pork Products

  • Jeong, Jong Youn;Bae, Su Min;Yoon, Jiye;Jeong, Da Hun;Gwak, Seung Hwa
    • Food Science of Animal Resources
    • /
    • v.40 no.5
    • /
    • pp.831-843
    • /
    • 2020
  • This study investigated the potential for using vegetable powders as a natural replacement for sodium nitrite and their effects on the physicochemical characteristics of alternatively cured pork products. We analyzed pork products subjected to four treatments: control (0.015% sodium nitrite), Chinese cabbabe powder (CCP) treatment (0.4% Chinese cabbage powder), radish powder (RP) treatment (0.4% radish powder), and spinach powder (SP) treatment (0.4% spinach powder). Among the vegetable powders prepared in this study, SP had the highest (p<0.05) nitrate content, while CCP had the lowest (p<0.05). The cooking yields from these treatments were not significantly different from each other. However, the products with vegetable powders had higher (p<0.05) pH and thiobarbituric acid reactive substances values than the control. Pork products with vegetable powders also showed lower CIE L values and higher CIE b values than the nitrite-added control. RP treatment had similar (p>0.05) CIE a values to the control, while SP treatment had the lowest (p<0.05) CIE a values. The residual nitrite content was lower (p<0.05) in the vegetable powder added pork products than in the control, although nitrosyl hemochrome and total pigment contents in the CCP and RP treatments were similar (p>0.05) to those in the control. The control, CCP, and RP treatments showed curing efficiencies greater than 80%, indicating that CCP and RP would be promising potential replacements for sodium nitrite. The results of this study suggest that RP may be a suitable natural replacement for sodium nitrite to produce alternatively cured meat products, compared to other leafy vegetable powders.

Effect of Nitrogen Sources on Mycelial Growth and Sclerotial Formation of Rhizoctonia solani Causing Rice Sheath Blight (벼 잎집무늬마름병균의 균사생장 및 균핵형성에 미치는 질소원의 효과)

  • Park Kyung Seok;Chung Bong Koo
    • Korean Journal Plant Pathology
    • /
    • v.1 no.1
    • /
    • pp.44-50
    • /
    • 1985
  • Effect of nitrogen sources on mycelial growth and sclerotial formation of Rhizoctonia solani causing rice sheath blight was studied by using sixty isolates from diseased samples of different localities in Chungbuk area. Based on the cultural characters, pathogenicity and sclerotial formation, three isolates of the fungus were selected. The virulence of the three isolates varied based on the percent of seeds germination, seedling blights and length and lesion number of lesions. As nitrogen sources, arginine, alanine, urea, ammonium sulfate and sodium nitrate were more effective for mycelial growth and sclerotial formation, than were cystine, methionine, lysine, histidine, tryptophan and thyrosine. The mycelium of R. so/ani grew well in a lower concentration of urea, sodium nitrate, arginine, ammonium sulfate and lysine, but in a higher concentration of proline, histidine, and alanine. In all nitrogen sources tested, high concentration of nitrogen nutrients greatly stimulated sclerotial formation of the fungus. Arginine, urea, and ammonium sulfate increased virulence of the fungus. All the isolates grown on the basic medium plus proline produced large sclerotia. Mycelial growth of the fungus was not well in the tryptophan-added medium, showing brown discoloration of medium.

  • PDF

Nitrate Removal by Pseudomonas fluorescens K4 Isolated from a Municipal Sewage Treatment Plant

  • Lee, O-Mi;Oh, Jong-Hyeok;Hwang, Doo-Seong;Choi, Yun-Dong;Chung, Un-Soo;Park, Jin-Ho;Kim, Min-Ju;Jeong, Seong-Yun;Lee, Sang-Joon
    • Journal of Environmental Science International
    • /
    • v.16 no.11
    • /
    • pp.1219-1223
    • /
    • 2007
  • The removal of nitrogen compounds from a wastewater is essential and it is often accomplished by bio-logical process. An aerobic nitrate-removing bacterium was isolated from a municipal sewage treatment plant and soil. On the basis of its morphological, cultural and physiological characteristics and 16S rRNA sequencing data, this strain was identified as Pseudomonas fluorescens, and named as P. fluorescens K4. The optimal conditions of the initial pH and temperature of media for its growth were $7.0{\sim}8.0$ and $30^{\circ}C$, respectively. P. fluorescens K4 was able to remove 99.9% of nitrate after 24 h in a culture. The strain could grow with a nitrate concentration up to 800 mg/l and was able to remove 99.9% of nitrate after 104 h of incubation. The optimal electron donor was sodium citrate for a nitrate removal. The strain K4 showed a capability of a complete nitrate removal when the initial C/N ratio was 1.0. An effect of the initial seed concentration was observed for a cell of 10% (v/v) for a nitrate removal. Especially P. fluorescens K4 could completely remove 200 mg/l ammonium for 3 days.

The Cultural Characteristics and Antibacterial Activities of Cordyceps militaris and Paecilomyces tenuipes (번데기동충하초와 눈꽃동충하초의 배양특성 및 항균활성)

  • Lee, Ki-Man;Hong, In-Pyo;Nam, Sung-Hee;Sung, Gyoo-Byung;Bae, Yoon-Hwan
    • Korean journal of applied entomology
    • /
    • v.47 no.4
    • /
    • pp.479-486
    • /
    • 2008
  • The cultural characteristics and antibacterial activities of Cordyceps militaris and Paecilomyces tenuipes were compared. The mycelial growth was the highest on MCM (Mushroom Complete Medium) for C. militaris and on YMA (Yeast Malt Agar) for P. tenuipes. But the mycelial density on MMM (Mushroom Minimal Medium) was lower than other on media. The optimum mycelial growth was observed at $25^{\circ}C$. C. militaris was low mycelial growth when it was transferred over 5 times generation. The carbon source for the optimum mycelial growth was fructose of monosaccharide, maltose of disaccharide and dextrin of polysaccharide. The calcium nitrate of organonitrogen was found the best mycelial growth on C. militaris, while the sodium nitrate observed to be well for mycelial growth on P. tenuipes. The ammonium tartrate was observed to be the best among the inorganonitrogen used for mycelial growth. Antibacterial activities were found out just C. militaris against Bacillus cereus of Gram (+).

Electrochemical polishing method using the point electrode tools(2nd) (점 전극을 이용한 전해연마 가공특성)

  • 이승훈;박규열;양순용
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 1999.05a
    • /
    • pp.251-255
    • /
    • 1999
  • In last paper, it was suggested electrochemical polishing method using the point electrode tools. It was aimed that Machining rate in ECM using the point electrode method should be ultimately small and also high dimension accuracy and surface integrity should be fine. In this paper, the machining characteristics were investigated by using the several types of electrolyte.

  • PDF

Effects of Rumen Protozoa of Brahman Heifers and Nitrate on Fermentation and In vitro Methane Production

  • Nguyen, S.H.;Li, L.;Hegarty, R.S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.29 no.6
    • /
    • pp.807-813
    • /
    • 2016
  • Two experiments were conducted assessing the effects of presence or absence of rumen protozoa and dietary nitrate addition on rumen fermentation characteristics and in vitro methane production in Brahman heifers. The first experiment assessed changes in rumen fermentation pattern and in vitro methane production post-refaunation and the second experiment investigated whether addition of nitrate to the incubation would give rise to methane mitigation additional to that contributed by defaunation. Ten Brahman heifers were progressively adapted to a diet containing 4.5% coconut oil distillate for 18 d and then all heifers were defaunated using sodium 1-(2-sulfonatooxyethoxy) dodecane (Empicol). After 15 d, the heifers were given a second dose of Empicol. Fifteen days after the second dosing, all heifers were allocated to defaunated or refaunated groups by stratified randomisation, and the experiment commenced (d 0). On d 0, an oral dose of rumen fluid collected from unrelated faunated cattle was used to inoculate 5 heifers and form a refaunated group so that the effects of re-establishment of protozoa on fermentation characteristics could be investigated. Samples of rumen fluid collected from each animal using oesophageal intubation before feeding on d 0, 7, 14, and 21 were incubated for in vitro methane production. On d 35, 2% nitrate (as $NaNO_3$) was included in in vitro incubations to test for additivity of nitrate and absence of protozoa effects on fermentation and methane production. It was concluded that increasing protozoal numbers were associated with increased methane production in refaunated heifers 7, 14, and 21 d after refaunation. Methane production rate was significantly higher from refaunated heifers than from defaunated heifers 35 d after refaunation. Concentration and proportions of major volatile fatty acids, however, were not affected by protozoal treatments. There is scope for further reducing methane output through combining defaunation and dietary nitrate as the addition of nitrate in the defaunated heifers resulted in 86% reduction in methane production in vitro.

Characteristics of $PM_{2.5}$ in Kanghwa (강화에서의 $PM_{2.5}$ 특성)

  • 최민규;여현구;임종억;조기철;김희강
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.16 no.6
    • /
    • pp.573-583
    • /
    • 2000
  • In order to investigate the characteristics of PM(sub)2.5 in the background area, the following pollutant were measured from February 1996 to June 1999 in Kanghwa: PM(sub)2.5 mass, sulfate, nitrate, chloride, ammonium, sodium, calcium, magnesium and potassium. The mean concentration of PM(sub)2.5 mass was 25.8$\pm$1.2$\mu\textrm{g}$/㎥(range 5.18~85.74). This value was higher than the annual PM(sub)2.5 US NAAQS(15$\mu\textrm{g}$/㎥) and the total number of samples higher than the 24-h PM(sub)2.5 US NAAQS(65$\mu\textrm{g}$/㎥) was seven. PM(sub)2.5 masses also showed temporal variations both yearly and seasonally. Total water soluble ions constituted about 45% of PM(sub)2.5 miss, and sulfate, nitrate and ammonium were main components in water soluble ions. Compared with the literature data from other areas, the measured PM(sub)2.5 concentrations were relatively high.

  • PDF

Studies on Reduction of Harmful Compound and Combustibility of $Na_3$ Citrate-treated Cigarette (시트르산나트륨첨가(添加)에 의(依)한 담배의 연소성(燃燒性) 및 유해물감소(有害物減少)에 관한 연구(硏究))

  • Kim, Ki-Hwan;Bae, Hyo-Won;Lee, Yong-Chong;Kim, Man-Uk;Park, Taek-Kyu
    • Applied Biological Chemistry
    • /
    • v.20 no.1
    • /
    • pp.117-122
    • /
    • 1977
  • Development of new burning additives against nitrate salts used in past tobacco industry examined to reduce harmful nitrogenous compounds in smoke. Among several additives treated, the best effect by means of elevation of combustibility and reduction of tar and nicotin contents in smoke was observed by adding sodium citrate from 0.6 to 1% in tabacco. The following results were obtained through investigating combustibility, chemical composition, and differential thermal analysis of the tabacco treated with the buring additives. 1) The close relation was observed between the levels of the smoke components and combustibility of the treated tabacco. 2) Differential thermal analysis (D.T.A.) of citrate-treated tobacco shows an increase in H. Value and a decrease in L. Value as compared with other tobacco sample. 3) The D.T.A. of sodium-nitrate and sodium-citrate shows that sodium-nitrate gives endothermal reaction at $270^{\circ}$ and $310^{\circ}$ and sodium citrate gives exothermal reaction at $290^{\circ}$ with endothermal reaction at $170^{\circ}\;and\;310^{\circ}$. 4) $Na_3-citrate-treated$ tobacco shows an increase in smoke generation between room temperature and $350^{\circ}$ (Zone A) and a decrease in smoke generation between $350^{\circ}$ and $900^{\circ}$ (Zone B) compared with untreated tobacco. The smoke from these tobacco also contains lower levels of Tar, Nicotine, Phenols, Nitrogen oxides and Benzpyrene, and elevation of static Burning rate.

  • PDF