• Title/Summary/Keyword: Free spray

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Spray Penetrations of Dimethyl Ether (DME) and Diesel for the Variation of Injection Rate (분사율 변화에 따른 Dimethyl Ether (DME)와 디젤의 분무도달거리)

  • Choi, Wook;Lee, Ju-Kwang;Bae, Choong-Sik
    • Transactions of the Korean Society of Automotive Engineers
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    • v.12 no.6
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    • pp.16-22
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    • 2004
  • Dimethyl Ether (DME) has been considered as one of the most attractive alternative fuels for a compression ignition engine. The major advantage of DME-fuelled engine is a great potential for soot-free combustion without sacrificing an inherent high thermal efficiency of diesel engine, despite a necessity for modification of the conventional fuel injection system. An experimental study on DME and conventional diesel sprays was conducted by employing a common-rail type fuel injection system with a 5-holes sac type nozzle, including a constant volume vessel pressurized with nitrogen gas. The injection rates of DME and diesel fuel were recorded with the Bosch type injection rate meter. The injection delay of DME was shorter than that of diesel fuel. The measured injection rates of DME and diesel fuel were correlated with spray penetrations. The prediction method of spray penetration was established using the injection rates, which was verified with the Dent's penetration model and found to agree well for DME case.

Development and Decay of Columnar Vortex in two faces interface ; gas/liquid and solid/liquid

  • Lee, Seung-Hwan;Kim, Kyung-Hoon;Kim, Seok-Woo
    • Journal of ILASS-Korea
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    • v.6 no.2
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    • pp.29-36
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    • 2001
  • Vortices terminating at free surface have been investigated extensively. however. are focused on surface parallel vortices and little has been known about surface normal vortex or columnar vortex. Visualized experimental results utilizing LlF technique are discussed for the purpose of characterization of columnar vortex interacting with a clean and a contaminated free surfaces and a solid body interface in the present investigation. The results reveal that surface tension changes due to surface contamination although bulk viscosity remains constant and eventually the behavior of a columnar vortex interacting with a contaminated free surface and a solid body interface are totally different from the clean free surface case.

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Evaluation of the Corrosion Resistance of Steel Coated with Zinc Using a Cr-free Coating Solution as a Function of Heat Treatment Time (Cr-free 코팅액에 의한 아연도금강판의 건조시간에 따른 내식특성)

  • Seo, Hyun-Soo;Moon, Hee-Joon;Kim, Jong-Soon;Ahn, Seok-Hwan;Moon, Chang-Kwon;Nam, Ki-Woo
    • Journal of Ocean Engineering and Technology
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    • v.24 no.5
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    • pp.67-74
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    • 2010
  • Chromate conversion coating is a coating technique used to passivate aluminum, zinc, cadmium, copper, silver, magnesium, tin, and their alloys to slow corrosion. The process uses various toxic chromium compounds, which may include hexavalent chromium. The industry is developing less toxic alternatives in order to comply with substance restriction legislation, such as RoHS. One alternative is to develop a Cr-free coating solution. In this study, eco-friendly, Cr-free solutions (urethane solution S-700, organic/inorganic solution with Si LRO-317) were used. Test specimens were dried in a drying oven at $190^{\circ}C$ for 3, 5, 7, and 9 minutes. Corrosion resistance was evaluated using a salt spray test for 72 hours. The results show that the optimum corrosion resistance was achieved at $190^{\circ}C$ for five minutes for EGI and three or five minutes for HDGI, respectively. The adhesive properties of the two types of coating solutions were superior regardless of drying time.

Effect of Uniconazole and Free Radical Scavenger Treatments on Reduction of $SO_2$ Injury in Platanus occidentalis (Uniconazole 및 Free Radical Scavenger처리가 양버즘나무의 $SO_2$ 피해경감에 미치는 효과)

  • Cho, Jeong-Hee;Ku, Ja-Hyeong;Choi, Jong-Myung
    • Korean Journal of Environmental Agriculture
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    • v.16 no.1
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    • pp.14-18
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    • 1997
  • The objective of this research was to increase phytoprotective effects by combined treatment of uniconazole and free radical scavengers such as ascorbic acid or sodium benzoate on $SO_2$ injury in P. occidentalis. The plant injury, chlorophyll content and enzyme activity of superoxide dismutase(SOD) and peroxidase(POD) affected by combined treatment were also investigated. The phytoprotective role of uniconazole was nullified by spray of Diethyldithiocarbamate(DDTC) resulting in the decrease of SOD and POD activities. Free radical scavengers, sodium benzoate and ascorbic acid, did not affect SOD and POD activity, but significantly inhibited the development of visible injury, degradation of chlorophyll, and SOD and POD activity in leaves exposed to $SO_2$. The spray of ascorbic acid decreased plant susceptibility to $SO_2$ induced by DDTC application. These results indicate that uniconazole application increase SOD activity that play a role of antioxidant in plant body, but sodium benzoate and ascorbic acid do not affect enzyme activities of SOD or POD.

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Nucleation and Growth of Bi-free and Superconducting Phases in Bi2Sr2Ca2.2CuO3Ox (Bi2Sr2Ca2.2CuO3Ox계에서 초전도상과 Bi-free상의 핵생성과 성장)

  • 오용택;신동찬;구재본;이인환;한상철;성태현
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.4
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    • pp.343-350
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    • 2003
  • Using Bi$_2$Sr$_2$Ca$_2$.$_2$Cu$_3$ $O_{x}$ powders prepared by solid state reaction and spray drying method, the nucleation and growth behaviors of superconducting and second phases were investigated during isothermal heat treatment. When the spray drying power was used in contrast with solid state reaction powder, Bi$_2$Sr$_2$Ca$_2$.$_2$Cu$_3$ $O_{x}$ (2223) phase could be formed at the relatively shot time and second phases were much bigger. Quantitative analysis showed that as the heat treatment time increased, more Bi$_2$Sr$_2$Ca$_2$.$_2$Cu$_3$ $O_{x}$ (2212) changed to 2223 and the major second phase was changed from (Sr,Ca)$_{14}$Cu$_{24}$ $O_{x}$(14:24) to (Sr,Ca)$_2$Cu$_1$ $O_{x}$ (2:l). The superconducting phase formed at the relatively short time 14:24 phase. Following the Bi-free phase of 14:24 Phase, but long time was needed in places far from the 14:24 phase. Following the formation of the 2212 phase near the 14:24 phase, the 2223 phase nucleated preferentially at the interface between the 2212 and 14:24 phases. The preferential nuclcation of 2223 was explained by its structural similarity and low Interfacial energy with both the Bi-free and 2212 Phases.12 Phases.

Quality Change of Cinnamon Extract Prepared with Various Drying Methods (건조 방법에 따른 계피 Extract의 품질 변화)

  • 김나미;김동희
    • The Korean Journal of Food And Nutrition
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    • v.13 no.2
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    • pp.152-157
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    • 2000
  • In order to select the optimum drying method for the production of cinnamon extract, water extract and 70% ethanol extract of cinnamon were prepared. And then several drying method of oven drying, vacuum evaporation, spray drying and freeze drying were performed. Content of cinnamic acid, cinnamic aldehyde, eugenol, tannin and free sugar, and antioxidant activity, degree of browning, pH, color value, turbity and solubility were compared. In water extract, contents of cinnamic acid, cinnamic aldehyde, eugenol were 29.45mg/100g, 94.86mg/100g, 120.75mg/100g and decreased to 4.76%∼44.21%, 5.30%∼48.05%, 3.66%∼21.83% by oven dyring, vaccum drying, spray drying respectively, but freeze drying showed a little decrease of those components. In 70% ethanol extract, effectual components decreased to 76.05%∼88.38% and 26.86%∼78.76% by freeze drying and vacuum evaporation respectively. Antioxidant activity decreased by drying and decreasing rate in 70% ethanol extract was lower than water extract. Degree of browning increased as the drying temperature increased. Tannin and free sugars were little affected by drying temperature. Solubility decreased in oven drying and 70% ethanol extract. Overall data suggested that optimum drying methods of cinnamon extract were freeze drying in case of water extract and freeze drying and vaccum drying in case of 70% ethanol extract.

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Effect of 8% lidocaine spray on the sensory and pain thresholds of the skin of the face and hands evaluated by quantitative sensory testing

  • Okayasu, Ichiro;Komiyama, Osamu;Ayuse, Takao;De Laat, Antoon
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.18 no.6
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    • pp.361-365
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    • 2018
  • Background: Recently, we examined the effects of 2% lidocaine gel on the tactile sensory and pain thresholds of the face, tongue and hands of symptom-free individuals using quantitative sensory testing (QST); its effect was less on the skin of the face and hands than on the tongue. Consequently, instead of 2% lidocaine gel, we examined the effect of 8% lidocaine spray on the tactile sensory and pain thresholds of the skin of the face and hands of healthy volunteers. Methods: Using Semmes-Weinstein monofilaments, QST of the skin of the cheek and palm (thenar skin) was performed in 20 healthy volunteers. In each participant, two topical sprays were applied. On one side, 0.2 mL of 8% lidocaine pump spray was applied, and on the other side, 0.2 mL of saline pump spray was applied as control. In each participant, QST was performed before and 15 min after each application. Pain intensity was measured using a numeric rating scale (NRS). Results: Both the tactile detection threshold and filament-prick pain detection threshold of the cheek and thenar skin increased significantly after lidocaine application. A significant difference between the effect of lidocaine and saline applications was found on the filament-prick pain detection threshold only. NRS of the cheek skin and thenar skin decreased after application of lidocaine, and not after application of saline. Conclusion: The significant effect of applying an 8% lidocaine spray on the sensory and pain thresholds of the skin of the face and hands can be objectively scored using QST.

Prognostic Value of Pathological Characteristics of Invasive Margins in Early-stage Squamous Cell Carcinomas of the Uterine Cervix

  • Khunamornpong, Surapan;Settakorn, Jongkolnee;Sukpan, Kornkanok;Suprasert, Prapaporn;Lekawanvijit, Suree;Siriaunkgul, Sumalee
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.9
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    • pp.5165-5169
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    • 2013
  • Background: To evaluate the pathological characteristics of invasive margins in early-stage cervical squamous cell carcinomas and their association with other clinicopathological features including clinical outcomes. Materials and Methods: Patients with FIGO stage IB-IIA cervical squamous cell carcinomas who received surgical treatment and had available follow-up information were identified. Their histological slides were reviewed for prognostic variables including tumor size, grade, extent of invasion, lymphovascular invasion, involvement of vaginal margin or parametrium, and lymph node metastasis. The characteristics of invasive margins including invasive pattern (closed, finger-like, or spray-like type), degree of stromal desmoplasia, and degree of peritumoral inflammatory reaction were evaluated along the entire invasive fronts of tumours. Associations between the characteristics of invasive margins and other clinicopathological variables and disease-free survival were assessed. Results: A total of 190 patients were included in the study with a median follow-up duration of 73 months. Tumour recurrence was observed in 18 patients (9%). Spray-like invasive pattern was significantly more associated as compared with closed or finger-like invasive pattern (p=0.005), whereas the degree of stromal desmoplasia or peritumoral inflammatory reaction was not. Low degree of peritumoral inflammatory reaction appeared linked with lymph node metastasis (p=0.021). In multivariate analysis, a spray-like invasive pattern was independently associated with marked stromal desmoplasia (p=0.013), whilst marked desmoplasia was also independently associated with low inflammatory reactions (p=0.009). Furthermore, low inflammatory reactions were independently associated with positive margins (p=0.022) and lymphovascular invasion (p=0.034). The patients with spray-like invasive pattern had a significantly lower disease-free survival compared with those with closed or finger-like pattern (p=0.004). Conclusions: There is a complex interaction between cancer tissue at the invasive margin and changes in surrounding stroma. A spray-like invasive pattern has a prognostic value in patients with early-stage cervical squamous cell carcinoma.

Elimination of Aster Yellows Phytoplasma from Dendranthema grandiflorum by Application of Oxytetracycline as a Foliar Spray

  • Chung, Bong-Nam;Park, Gug-Seoun
    • The Plant Pathology Journal
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    • v.18 no.2
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    • pp.93-97
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    • 2002
  • Aster yellows phytoplasma-infected chrysanthemums showing stunt, rosette, and excessive branching were treated with a foliar spray of 400 mg/I oxytetracycline at three-day interval for 1,2,3 and 4 months. Two months after the final treatment, new shoots from the recovered chrysanthemums showed the recurrence of the disease symptoms. However, cuttings from chrysanthemums treated with oxytetracycline did not express any photoplasma infection symptoms for more than 10 months. Also, chrysanthemums dipped in 100 mg/I oxytetracycline solution combined with a foliar spray of 400 mg/I oxytetracycline for 4 weeks showed the same results. Using an electron microscope, ultrathin sections of leaf midribs of chrysanthemum cuttings treated with oxytetracycline for 4 months did not show phytoplasma bodies 10 months after treatment. Nucleic acids from chrysanthemums, which did not express phytoplasma infection symptoms for more than 10 months, did not amplify 16S rRNA gene of phytoplasma by polymerase chain reaction. These results may have implications in the propagation of phytoplasma-free healthy stocks for a wide range of plant species.