• Title/Summary/Keyword: hot-plate test

Search Result 165, Processing Time 0.031 seconds

Experimental Study on Correction of Thermal Conductivity Obtained by Heat Flow Method using Commercial Guarded Hot Plate Method Apparatus (상용 보호열판법 열전도율 측정장비를 사용한 열유속법의 열전도율 값 보정에 대한 실험적 연구)

  • Lee, Jin-Sung;Kim, Kyung-Su;Kim, Yooil;Woo, Suck-Min;Yun, Seungjin
    • Journal of Ocean Engineering and Technology
    • /
    • v.29 no.2
    • /
    • pp.169-174
    • /
    • 2015
  • This paper addresses experimental methodologies to measure the temperature-dependent thermal conductivity of the insulation materials popularly used for LNG cargo containment systems. The measurement techniques considered in this paper are the guarded hot plate (GHP) method and heat flow method (HFM). The former is based on the power supplied to the hot plate to keep the temperature constant, and the latter is based on a direct heat flux measurement. In order to improve the accuracy of the HFM, the thermal conductivity obtained by GHP was cross-compared with the HFM results, and a calibration factor was derived. It was found that the thermal conductivities measured by the two methods corresponded well under room temperature, but the deviation tended to slightly increase as the temperature decreased. Because of the easy installation and operability of HFM, it can be used to measure thermal conductivity in a large scale mock-up test or unit insulation panel test, where the GHP method is difficult to apply.

Neuropharmacological Activity of Humulus lupulus Extracts

  • Lee, Kang-Mee;Jung, Jun-Sub;Song, Dong-Keun;Kim, Yung-Hi
    • Korean Journal of Pharmacognosy
    • /
    • v.24 no.3
    • /
    • pp.231-234
    • /
    • 1993
  • Neuropharmacological profile of Humulus lupulus (hop) extract was studied in mice. At doses above 100 mg/kg(i.p.), it decreased spontaneous locomotor activity and raised the nociceptive threshold in the hot-plate test. At doses above 250 mg/kg (i.p.), it increased pentobarbital-induced sleeping time and produced muscle relaxant effect. At the dose of 500 mg/kg, anticonvulsive effect against pentylenetetrazole-induced convulsion and hypothermic effect was observed.

  • PDF

Evaluation of the antinociceptive effects of a selection of triazine derivatives in mice

  • Hajhashemi, Valiollah;Khodarahmi, Ghadamali;Asadi, Parvin;Rajabi, Hamed
    • The Korean Journal of Pain
    • /
    • v.35 no.4
    • /
    • pp.440-446
    • /
    • 2022
  • Background: The authors showed in a previous study that some novel triazine derivatives had an anti-inflammatory effect. The present study was designed to evaluate the antinociceptive effect of five out of nine compounds including two vanillintriazine (5c and 5d) and three phenylpyrazole-triazine (10a, 10b, 10e) derivatives which showed the best anti-inflammatory effect. Methods: Male Swiss mice (25-30 g) were used. To assess the antinociceptive effect, acetic acid-writhing, formalin, and hot plate tests were used after intraperitoneal injection of each compound. Results: All compounds significantly (P < 0.001) reduced acetic acid-induced writhing at tested doses (50, 100, and 200 mg/kg). Also, the percent inhibition of writhing in the acetic acid test showed that at the maximum tested dose of these compounds (200 mg/kg), the order of potencies is as follows: 10b > 10a > 10e > 5d > 5c. In the formalin test, compounds 5d, 10a, and 10e showed an antinociceptive effect in the acute phase and all compounds were effective in the chronic phase. In the hot plate test, compounds 5c, 5d, and 10a demonstrated an antinociceptive effect. Conclusions: The results clearly showed that both vanillin-triazine and phenylpyrazole-triazine derivatives had an antinociceptive effect. Also, some compounds which showed activity in the early phase of formalin test as well as in the hot plate test could control acute pain in addition to chronic or inflammatory pain.

Evaluation of stress-induced analgesia in acupuncture analgesic effect - An Approach on diameters of acupuncture needles and acupuncture point needlings - (침진통 효과에서 스트레스에 의한 진통 효과 개입 여부 평가 - 침굵기, 침자극 부위를 중심으로 -)

  • Jeong, Byeong-Ju;Choe, Il-Hwan;Shin, Hee-Sup;Lim, Sabina
    • Korean Journal of Acupuncture
    • /
    • v.25 no.3
    • /
    • pp.65-80
    • /
    • 2008
  • Objective : In recent years, many investigators have questioned whether the analgesic effect of acupuncture is simply related to the stress-induced analgesia (SIA). However, there has been lack of studies on this issue. In this study, the stress levels induced by manual acupunctures are compared with the stress in animal experiment models. The experiments have been carried out with Sprague Dawley (SD) rats. Method : For stress level evaluation, Hot plate test has been used. Maximum Possible Effect (MPE) has been measured by checking the pre-test time and post-test time. Cortisol and corticosterone concentrations in serum were measured by enzyme-linked immunosorbent assay (ELISA). Results : In the hot plate test, MPE values of post-test time were significantly decreased after 10 minutes than after 5 minutes. Therefore, optimal time interval was chosen as 10 minutes. There was significant difference of MPE values between Suspension group and all other treatment groups. However, there were no significant differences of MPE values between Sham group and all other treatment groups. However, MPE values showed tendency to decrease when acupuncture needle diameter increased. MPE values of ST040, ST040(lido), NAP040(lido) groups were markedly decreased than that of Suspension group, while that of NAP040 group was substantially increased than that of Sham group increased in acupoint and nonacupoint models. Serum cortisol concentrations of treatment groups were not significantly different from that of Suspension and Sham groups. Serum corticosterone concentration of 0.25 mm group was substantially increased than that of compared with Sham group. Serum cortisol and corticosterone concentrations of treatment groups were not significantly different from those of Suspension and Sham groups in acupoint and nonacupoint models. Conclusion : From hot plate test and serum stress hormones concentrations, it is found that manual acupuncture treatment induces negligible stress or SIA on ST36. And the stress induced by manual acupuncture is more closely related to acupuncture point needlings than diameters of acupuncture needles.

  • PDF

Antinociceptive and gastro-protective effect of the ethanolic extract of the flowering top of Anthocephalus Cadamba Roxb

  • Subhan, Nusrat;Hasan, Raquibul;Hossain, Mokarram;Akter, Raushanara;Majumder, Muntasir Mamun;Rahman, Mostafizur;Ahmed, Kamaluddin;Ghani, Abdul;Alam, Ashraful
    • Advances in Traditional Medicine
    • /
    • v.9 no.4
    • /
    • pp.326-334
    • /
    • 2009
  • The effect of alcoholic extract of Anthocephalus (A.) Cadamba Roxb. was evaluated in experimental models of pain and ulcer. Hot tail flick test, hot plate test and acetic acid induced writhing test were employed for evaluating the peripheral as well as central analgesic mechanism exerted by the extracts. Gastroprotective activity was examined by HCl and ethanol induced gastric damage test. Test group received crude extract 500 mg/kg showed maximum time needed for the response against thermal stimuli (6.26 ${\pm}$ 0.439 s) which is comparable to diclofenac sodium (6.56 ${\pm}$ 0.381 s) in hot tail flick method. These experimental results also followed the experimental results of hot plate test where crude extract 500 mg/kg showed maximum time needed for the response against thermal stimuli (4.74 ${\pm}$ 0.234 s) which is comparable to diclofenac sodium (5.58 ${\pm}$ 0.585 s). The crude extract at 500 and 250 mg/kg showed significant reduction in acetic acid induced writhing in mice with a maximum effect of 68.026% reduction at 500 mg/kg dose which is comparable to standard diclofenac sodium (79.93%). In gastroprotective study the extract of A. Cadamba (250 and 500 mg/kg) significantly inhibited ulceration induced by both HCl and ethanol dose dependently. Results of the study suggest that the extract possesses both analgesic and gastroprotective activity on mice.

Anti-depressant Effect of the Extracts of Aconitum carmichaeli (부자(附子)의 우울증 억제효과에 관한 연구)

  • Chang, Moon-Kyoo;Kim, Geun-Woo;Koo, Byung-Soo
    • Journal of Oriental Neuropsychiatry
    • /
    • v.20 no.3
    • /
    • pp.49-64
    • /
    • 2009
  • Objectives : The water and methanol extracts of Aconitum carmichaeli(Aconiti Tuber Preparat) were investigated for their anti-depressant effects. Methods : In this study, reserpine-induced hypothermia test, tail suspension test and hot plate test. Additionally, the brain monoamine oxidase activity was determined in vivo. Results: In the reserpine-induced hypothermia test, both extracts suppressed the fall of body temperature compared to the control group in a dose-dependent manner, suggesting the inhibition on hypothermia. In the tail suspension test, the methanol extract dose-dependently reduced the duration of immobility by 28.4% at a dose of 1 g/kg compared to control group, which is more effective than the water extract. In the hot plate test, the water extract and methanol extract increased the jump latency time compared to the control group, showing the inhibition rate of 198% and 182%, respectively, at a dose of 1 g/kg. Methanol extracts potently inhibited the brain monoamine oxidase activity in an in vivo assay compared to the control group, showing 84.6% inhibition, but the water extract revealed very weak activity. Conclusions : Above results suggested that the extract of Aconitum carmichaeli can be useful for the prevention and treatment of depression.

  • PDF

In Vivo Anti-Nociceptive and Anti-Inflammatory Effect of the Two Triterpenes, Ursolic Acid and 23-Hydroxyursolic Acid, from Cussonia bancoensis

  • Tapondjou, L.A.;Lontsi, David;Sondengam, Beiban-Luc;Choi, Jong-Won;Lee, Kyung-Tae;Jung, Hyun-Ju;Park, Hee-Juhn
    • Archives of Pharmacal Research
    • /
    • v.26 no.2
    • /
    • pp.143-146
    • /
    • 2003
  • Triterpenoids, ursolic acid (1) and 23-hydroxyursolic acid (2) were obtained from the hydrolysis of BuOH fraction of Cussonia bancoensis extract to test anti nociceptive and anti-inflammatory effect of C. bancoensis (Araliaceae). Compound 1 and 2 exhibited anti-nociceptive effects, which were determined by acetic acid-induced writhing test and hot plate test. The effect of 2 was much more potent in acetic acid-induced writhing test than in hot plate test. Compound 1 and 2 significantly inhibited 1%-carrageenan-induced edema in the rat. These results suggest that the two triterpenes, ursolic acid and 23-hydroxyursolic acid, are responsible for the antinociceptive and anti-inflammatory effect of C. bancoesnsis.

Evaluation of Laser Welding Characteristics of 1.5GPa Grade Ultra High Strength Steel for Automotive Application (1.5GPa급 자동차용 고강도강의 레이저 용접부 특성평가)

  • Kim, Yong;Park, Ki-Young;Lee, Kyoung-Don;Jeong, Jun-Kou;Kim, Dong-Wha
    • Laser Solutions
    • /
    • v.13 no.4
    • /
    • pp.1-6
    • /
    • 2010
  • Recently the use of ultra high strength steels (UHSS) in structural and safety component is rapidly increasing in the automotive industry. For example, 1.5GPa grade hot stamping with die-quenching of boron steel 22MnB5 could apply crash-resistant parts such as bumpers and pillars. The development of laser welding process of hot stamping steels, fundamental bead-on-plate welding and lap joint welding test were carried out using 3kW Nd:YAG laser. Local hardening & HAZ softening occurred in hot stamping steel as a result of metallurgical change caused by the welding heat input in the Nd:YAG laser welding process. The size of soft zones in the hot stamping steel was related to the welding heat input, being smaller at high speeds which generated a smaller heat input. Also in the case of lap joint design structure, same welded characteristics were shown. The HAZ softening degree was controlled to ensure the joint strength.

  • PDF

Development of Flow Control Valves for Hot Water Distribution Manifolds (온수분배기용 유량제어밸브의 개발)

  • Kwon, Woo-Chul;Yoon, Joon-Yong;Yoo, Sun-Hak
    • The KSFM Journal of Fluid Machinery
    • /
    • v.13 no.4
    • /
    • pp.11-17
    • /
    • 2010
  • The developed control valves, installed on the hot water distribution manifolds for the floor heating system, consist of the balancing valves and the shut-off valves. The balancing valve was designed to improve the flow control performance and to reduce the noise emitted from the valve by modification of the general V port. The port of the shut-off valve was designed with two ceramic plates, working by rotating upper plate, to improve the duration and to reduce the noise. For the evaluation of the new valves, the flow rate was measured and noise level test was carried out. The test results showed that the error of the flow rate accuracy test for the flow balance of each manifold circuit was less than ${\pm}3%$ and the noise level was less than 35 dB(A).

Comparison of Service Style for plate waste in Industry Foodservice Operation (산업체 급식소의 배식방법에 따른 음식 잔식량에 대한 실태 조사연구)

  • 김혜영
    • Korean journal of food and cookery science
    • /
    • v.16 no.5
    • /
    • pp.416-424
    • /
    • 2000
  • Food waste is inevitable in any institutional food system. Although many factors contribute to plate waste, few quantitative studies of plate waste have actually been carried out. This study was undertaken to check (a) how the service style that affects the amount of plate waste, (b) the difference of plate waste between men and women and, (c) the influence of plate waste and customers'satisfaction to served meal. The survey was conducted through March 15 and April 9, 2000 by weighing the amount of plate waste and by questionnaires. Statistical data analysis was completed using the SPSS-PC program for descriptive analysis and ANOVA test. The results were as follows; (1) The largest amount, plate waste percentage measured were 19% of‘Hot alaska pollack soup’and 18% of‘Kuansh soup’respectively. (2) Amount of leftovers can be reduced if the pre-portioned serving style is changed to self-portioned serving. (3) The main reasons for leaving leftover were‘served too often’and‘disliked food’. (4) The customers'satisfaction rate was highly correlated with the leftover amounts.

  • PDF