• Title/Summary/Keyword: Effective permeability

Search Result 533, Processing Time 0.026 seconds

A Study on Application of Warm-Mix Quiet Pavement Using Fine-Size Aggregate (소입경 골재를 이용한 중온 저소음 아스팔트 포장의 적용 연구)

  • Jo, Shinhaeng;Baek, Yujin;Kim, Nakseok
    • Journal of the Society of Disaster Information
    • /
    • v.9 no.1
    • /
    • pp.56-64
    • /
    • 2013
  • The study examines the quiet pavement using fine-size aggregates and warm-mix technique to reduce traffic noise. In order to evaluate the quality of pavement, mix design and laboratory tests were carried out. Test results showed that using 10mm aggregates can reduce the cantabro loss compared with 13mm aggregates due to increase contact area between aggregates. Mixing and compaction temperatures of warm mix quiet pavement should be determined by gyratory compactor test because it is used high viscosity asphalt binder. Using warm-mix additive could reduce compaction temperature by about $15^{\circ}C$. Noise measurement and permeability tests were conducted at the test road for evaluation of the field performance. All of quiet pavements meet the standard of permeability and have sufficient porosity. Noise reduction of the quiet pavement using fine-size aggregates is more effective than that using 13mm aggregates. In particular, the effect of noise reduction was noticeable at low speeds.

Study on the Anti-inflammatory Effects of Seungmagalgeuntanggamibang(SMG) (升麻葛根湯加味方이 消炎작용에 미치는 영향)

  • Song, Seong-Pil;Kim, Jin-Man;Lim, Kyu-Sang;Kim, Nam-Kwen;Kwen, Il-Ho
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
    • /
    • v.17 no.2
    • /
    • pp.12-30
    • /
    • 2004
  • This study was carried out to investigate the effects of SMG on the in vitro and in vivo inflammatory reactions. In experiment I, in vitro tests, ethanol extract of SMG showed potent radical scavenging activity tested by DPPH(I,1-diphenyl-2-picryl-hyrazyl) method and inhibited the lipopolysaccharide-induced gene expressions of interleukin-1${\beta}$, interleukin-6 and tumor necrosis factor-${\alpha}$ (above 50$\%$ at a concentration of 50㎍/㎖) by the macrophage RAW 246.7 cells. Among the herbal ingredients of SMG, ethanol extracts of Scutellaria baicalensis, Paeonia lactiflora, Glycyrrhiza glabra showed potent radical scavenging activity. And Glycyrrhiza glabra and Scutellaria baicalensis showed potent inhibitory activity of nitric oxide production. Especially, ethanol extract of Scutellaria baicalensis inhibited the gene expression of IL-1${\beta}$, IL-6 and TNF-${\alpha}$. In cyclooxygenase-2 assay, Scutellaria baicalensis and Glycyrrhiza glabra showed the potent inhibition of prostaglandin E2 generation. In experiment 2, in vivo tests, SMG showed inhibitory effects on vascular permeability (28.7$\%$) and leukocyte migration (11.5$\%$). These results mean that SMG has a anti-inflammatory effects by it's inhibitory effects of leukocyte migration and vascular permeability as well as it's inhibitory effects of lipopolysaccharide-induced gene expression of IL-1${\beta}$, IL-6 and TNF-${\alpha}$, and radical scavenging activity. Therefore, I expect that SMG may be used as a effective drug for treatment on inflammation.

  • PDF

RELATION BETWEEN MICROSTRUCTURE AND SOFT MAGNETIC PROPERTIES OF Fe-TM-C-N (TM:Hf, Zr AND Nb) NANOCRYSTALLINE FILMS

  • Ryu, H.J.;Choi, J.O.;Han, S.H.;Kim, H.J.;Lee, J.J.;Kang, I.K.
    • Journal of the Korean Magnetics Society
    • /
    • v.5 no.5
    • /
    • pp.519-523
    • /
    • 1995
  • The Fe-TM-C-N nanocrystalline films (TM : Hf, Zr and Nb) are investigated to examine the relation between microstructure and soft magnetic properties. In these films, as the atomic radius of TM element increases, $P_{N2}$ which was added to get good soft magnetic properties was decreased and the maximum value of the permeability shifted to the high Fe range in the composition diagram. The best soft magnetic properties achieved in these films are : Hc of 0.15 Oe, $\mu_{eff}$ of 7800 (1MHz) and $4{\pi}M_{s}$ of 17.5 kG in Fe-Hf-C-N film ; Hc of 0.06 Oe, $\mu_{eff}$ of 2750 (1MHz) and $4{\pi}M_{s}$ of 16.8 kG in Fe-Zr-C-N film and Hc of 0.31 Oe; $\mu_{eff}$ of 2100 (1MHz) and $4{\pi}M_{s}$ of 15.5 kG in Fe-Nb-C-N film. It was considered that the stronger the bonding force between TM and C(N), the finer TM(C,N) phase is precipitated and therefore, the finer $\alpha$-Fe grains are formed. The effective permeability of the Fe-Zr-C-N films and Fe-Nb-C-N films remains nearly constant up to 10 MHz.

  • PDF

Effects of Permalloy Multilayered Schemes and CoZrNb Intermediate Layer on Recording Characteristics of CoCr/NiFe Media (Permalloy 다층화와 CoZrNb 중간층이 CoCr/NiFe 매체의 기록특성에 미치는 영향)

  • 장평우;이택동;박관수
    • Journal of the Korean Magnetics Society
    • /
    • v.4 no.1
    • /
    • pp.20-24
    • /
    • 1994
  • The read/write characteristics of CoCr/NiFe double layered media are strongly affected by the magnetic properties of NiFe magnetic soft layer as well as those of CoCr recording layer. Modification of the permalloy layer by NiFe/Ge multilayer scheme resulted in the higher recording sensitivity and the higher reproduced voltage of CoCr/NiFe medium and this is attributed to the higher permeability of the back layer and high perpendicular anisotropy of the CoCr recording layer. Although higher permeability of back layer results in higher recording sensitivity, the increment of the reproduced voltage was not remarkable, which can be confirmed in the FEM numerical analysis. On the contrary, peak shift characteristics of the CoCr/NiFe medium with the NiFe multi back layer was deteriorated compared to that of the CoCr/NiFe medium with NiFe single back layer. Insertion of ferromagnetic thin CoZrNb intermediate layer between CoCr and NiFe layer was effective to ensure large reproduced voltage and low peak shift. These recoridng characteristics were also discussed in connection with microstructural characteristics.

  • PDF

Semi-Rational Screening of Probiotics from the Fecal Flora of Healthy Adults against DSS-Induced Colitis Mice by Enhancing Anti-Inflammatory Activity and Modulating the Gut Microbiota

  • Wang, Weiwei;Xing, Wentao;Wei, Sichen;Gao, Qiaoying;Wei, Xinliang;Shi, Liang;Kong, Yu;Su, Zhenhua
    • Journal of Microbiology and Biotechnology
    • /
    • v.29 no.9
    • /
    • pp.1478-1487
    • /
    • 2019
  • Ulcerative colitis (UC), a chronic inflammatory bowel disease, substantially impacts patients' health-related quality of life. In this study, an effective strategy for discovering high-efficiency probiotics has been developed. First, in order to survive in the conditions of the stomach and intestine, high bile salt-resistant and strong acid-resistant strains were screened out from the fecal flora of healthy adults. Next, the probiotic candidates were rescreened by examining the induction ability of IL-10 (anti-inflammatory factor) production in dextran sodium sulfate (DSS)-induced colitis mice, and Lactobacillus sakei 07 (L07) was identified and selected as probiotic P. In the end, fourteen bifidobacterium strains isolated from stools of healthy males were examined for their antimicrobial activity. Bifidobacterium bifidum B10 (73.75% inhibition rate) was selected as probiotic B. Moreover, the colonic IL-6 and $TNF-{\alpha}$ expression of the DSS-induced colitis mice treated with L. sakei 07 (L07) - B. bifidum B10 combination (PB) significantly decreased and the IL-10 expression was up-regulated by PB compared to the DSS group. Furthermore, Bacteroidetes and Actinobacteria decreased and Firmicutes increased in the DSS group mice, significantly. More interestingly, the intestinal flora biodiversity of DSS colitis mice was increased by PB. Of those, the level of B. bifidum increased significantly. The Bacteriodetes/Firmicutes (B/F) ratio increased, and the concentration of homocysteine and LPS in plasma was down-regulated by PB in the DSS-induced colitis mice. Upon administration of PB, the intestinal permeability of the the DSS-induced colitis mice was decreased by approximately 2.01-fold. This method is expected to be used in high-throughput screening of the probiotics against colitis. In addition, the L. sakei 07 - B. bifidum B10 combination holds potential in UC remission by immunomodulatory and gut microbiota modulation.

Manufacture and evaluation of hydrogel preparations that are easy to use in emergency allergy situations (응급알레르기 상황에서 사용하기 쉬운 하이드로겔 제제의 제조 및 평가 과정)

  • Kim, Chul-tae;Kim, Hoon
    • Journal of Digital Convergence
    • /
    • v.19 no.3
    • /
    • pp.287-293
    • /
    • 2021
  • Tablets were conventionally used to treat choline urticaria. Disadvantages of tablets included sleep inducing problems, accessibility and reduced dosage. To address this, hydrogel containing Cetirizine HCl was manufactured. The experimental method was to measure viscosity, gel fraction, degree of swelling, content evaluation, and permeability. Studies have shown that hydrogels containing Cetirizine HCl can be directly applied to occurrence area to improve Cholinergic urticaric with minimal side effects associated with the marketable tablets. This hydrogel includes other important substances including steroids which gives it an advantage when applied on the skin, improving its accessibility. In addition, it is expected that the drug manufacturing process will be able to proceed as this hydrogel is effective even when used alone.

An Experimental Study on Engineering Properties of Self-healing Mortar according to PCC(Powder Compacted Capsule) Size and Mixing Ratio (PCC(Powder Compacted Capsule) 크기 및 혼입율에 따른 자기치유 모르타르의 공학적 특성에 관한 실험적 연구)

  • Jae-In, Lee;Chae-Young, Kim;Se-Jin, Choi
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.10 no.4
    • /
    • pp.514-522
    • /
    • 2022
  • In this study, as part of a study to improve the self-healing performance of concrete structures by applying self-healing capsules made of cementitious materials to cement composite materials, the engineering characteristics of mortars according to PCC(Powder Compacted Capsule) size and mixing ratio were compared and analyzed. For this, fluidity, compressive strength, reload test, carbonation, ultrasonic velocity, and water permeability characteristics were measured according to PCC size and mixing ratio of mortar. As a result of the measurement, the fluidity and compressive strength increased as the mixing ratio of PCC increased, and in the case of the load reload test, the healing ratio increased as the mixing ratio of PCC increased in the 03PC formulation. In the case of water permeability test, it was found that when PCC was used, the reduction ratio of water flow was up to 35 % higher than that of Plain, and when PCC with a size of 0.3 to 0.6 mm was mixed with 15 %, it was found to be effective in improving the crack healing ratio of the mortar.

Korean Red Ginseng extract treatment prevents post-antibiotic dysbiosis-induced bone loss in mice

  • Ho Jun Kang;Nicholas Chargo;Soumya Chennupati;Kerri Neugebauer;Jae Youl Cho;Robert Quinn;Laura R. McCabe;Narayanan Parameswaran
    • Journal of Ginseng Research
    • /
    • v.47 no.2
    • /
    • pp.265-273
    • /
    • 2023
  • Background: The intestinal microbiota is an important regulator of bone health. In previous studies we have shown that intestinal microbiota dysbiosis, induced by treatment with broad spectrum antibiotics (ABX) followed by natural repopulation, results in gut barrier dysfunction and bone loss. We have also shown that treatment with probiotics or a gut barrier enhancer can inhibit dysbiosis-induced bone loss. The overall goal of this project was to test the effect of Korean Red Ginseng (KRG) extract on bone and gut health using antibiotics (ABX) dysbiosis-induced bone loss model in mice. Methods: Adult male mice (Balb/C, 12-week old) were administered broad spectrum antibiotics (ampicillin and neomycin) for 2 weeks followed by 4 weeks of natural repopulation. During this 4-week period, mice were treated with vehicle (water) or KRG extract. Other controls included mice that did not receive either antibiotics or KRG extract and mice that received only KRG extract. At the end of the experiments, we assessed various parameters to assess bone, microbiota and in vivo intestinal permeability. Results: Consistent with our previous results, post-ABX- dysbiosis led to significant bone loss. Importantly, this was associated with a decrease in gut microbiota alpha diversity and an increase in intestinal permeability. All these effects including bone loss were prevented by KRG extract treatment. Furthermore, our studies identified multiple genera including Lactobacillus and rc4-4 as well as Alistipes finegoldii to be potentially linked to the effect of KRG extract on gut-bone axis. Conclusion: Together, our results demonstrate that KRG extract regulates the gut-bone axis and is effective at preventing dysbiosis-induced bone loss in mice.

An Experimental Study on the Effect of Malfunctioning of Drainage System on NATM Tunnel Linings (NATM 터널의 배수시스템 수리기능저하가 터널 라이닝에 미치는 영향)

  • Shin, Jong-Ho;Kwon, Oh-Yeob;Shin, Yong-Suk;Yang, Yu-Hong
    • Journal of the Korean Geotechnical Society
    • /
    • v.23 no.6
    • /
    • pp.77-84
    • /
    • 2007
  • One of the most sensitive design specifications to be considered is infiltration and external pore-water pressures on underground structure construction. Development of pore-water pressure may accelerate leakage and consequently cause deterioration of the lining. In this paper, the development of pore-water pressure due to malfunctioning of drainage system and its potential effect on the linings are investigated using physical model tests. The deterioration procedure was simulated by controlling both permeability and flow rate. Development of pore-water pressure was monitored on the lining using pore pressure measurement cells. Test results identified the mechanism of pore-water pressure development on the tunnel lining. In addition, they showed that controlling flow rate is more effective method fur simulating deterioration procedure than permeability control. The laboratory model tests were reproduced using coupled numerical method, and showed that the effect of deterioration of drainage system can be theoretically expected using coupled numerical modeling method.

Numerical analysis of the continuous casting process in the presence of thermo-solutal convection (열농도대류를 고려한 연속주조공정의 수치해석)

  • Jeong, Jae-Dong;Yu, Ho-Seon;Lee, Jun-Sik
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.21 no.3
    • /
    • pp.445-456
    • /
    • 1997
  • Continuous casting process is numerically analyzed using the continuum model in a non-orthogonal coordinate system. Flow damping in the mush is modeled by combining the viscosity dependence on liquid fraction in dilute mush and the permeability dependence on liquid fraction in concentrated mush. The effect of turbulence is indirectly considered by effective diffusivity determined elsewhere by experiment. The main objective is to investigate the effects of casting parameters such as casting speed and tundish superheat on the distribution of surface temperature, shell thickness, metallurgical length and centerline segregation. Some of the computed results are compared with available experiments, and reasonable agreements are obtained.