• Title/Summary/Keyword: Cut-off delamination

Search Result 3, Processing Time 0.022 seconds

Fabrication and Characterization of Alumina Hollow Fiber Ultrafiltration Membrane (알루미나 중공사 한외여과막 제조 및 특성평가)

  • Kim, Yeo-Jin;Kim, Seong-Joong;Kim, Jeong;Cho, Young-Hoon;Park, Hosik;Lee, Pyung-Soo;Park, You-In;Park, Ho-Bum;Nam, Seung-Eun
    • Membrane Journal
    • /
    • v.28 no.1
    • /
    • pp.21-30
    • /
    • 2018
  • In this study, homogeneous and defect-free ceramic ultrafiltration membranes were fabricated by using the sol-gel method. A boehmite sol was synthesized and coated onto the surface of alumina hollow fiber microfiltration membranes. The effect of sol viscosity and surface tension on the coating layer homogeneity and thickness was investigated. The optimum coating repetition using pristine sol was determined to be 3 times, as the samples coated more than 4 times showed delamination. Fixing the coating repetition to 3 times, the effect of sintering temperature was also studied in this work. The samples sintered at $1000^{\circ}C$ exhibited the highest pure water permeability with the molecular weight cut-off (MWCO) of approximately 51 kDa (10 nm dextran), and the samples sintered at 600, $800^{\circ}C$ displayed the MWCO of 12 kDa (5 nm dextran). The ultrafiltration membranes prepared in this work showed competitive performance compared to the reported ceramic ultrafiltration membranes.

An Experimental Study on the Shear Behavior of Reinforced Concrete Beams Strengthened with Slit Type Steel Plates (Slit형(形) 강판으로 보강(補强)한 철근콘크리트 보의 전단거동에 관한 실험연구)

  • Lee, Choon-Ho;Shim, Jong-Seok;Kwon, Ki-Hyuk
    • Journal of the Korean Society of Hazard Mitigation
    • /
    • v.8 no.4
    • /
    • pp.1-8
    • /
    • 2008
  • RC beam of existing structures often encounter shear problems for various reasons. The shear failure of RC beam is sudden and brittle. Strengthening technique jacketing with external bonding of steel plates(or CFRP and CFS) with epoxy is many use to in practice. This study presents test results on strengthening shear deficient RC beams by external bonding of slit type steel plates. Test parameters are width, interval, length, thickness and angle of slit in steel plates. The purpose was to evaluate the reinforcing effects, failure modes and shear capacities for RC beams of strengthened with various slit type steel plates. The test result confirmed that all slit steel plates improved the stiffness and strength of the specimens significantly. Failure modes of SV series and SD series showed shear fractures and flexure fractures at ultimate state respectively. SD series were ductile rather than SV series.

Lymph Node Ratio is More Predictive than Traditional Lymph Node Stratification in Lymph Node Positive Invasive Breast Cancer

  • Bai, Lian-Song;Chen, Chuang;Gong, Yi-Ping;Wei, Wen;Tu, Yi;Yao, Feng;Li, Juan-Juan;Wang, Li-Jun;Sun, Sheng-Rong
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.2
    • /
    • pp.753-757
    • /
    • 2013
  • Objective: To evaluate the relationships between lymph node ratio (LNR, the ratio of positive lymph nodes in excised axillary lymph nodes) and disease-free survival (DFS) by comparing with traditional absolute positive lymph node number (pN classification) for prediction of breast cancer (BC) progrnosis. Methods and Patients: We retrospectively reviewed patients who received comprehensive therapy in Department of Breast Surgery, Hubei Cancer Hospital, China from Jan 2002 to Dec 2006 (Group A), and Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, China from Jun 2008 to May 2012 (Group B). Patients were allocated to low-risk (${\leq}0.20$), intermediate-risk (> 0.20 but ${\leq}0.65$), high-risk (>0.65) groups by LNR. The primary endpoint was 5-DFS. Results: A total of 294 patients were included in our study. LNR was verified as a negative prognostic factor for DFS (P=0.002 in Group A, P<0.0001 in Group B). Then we found the effects of pN and LNR delamination on disease-free survival (DFS) had statistical significance (P=0.012 for pN and P=0.031 for LNR stratification in Group A, both of them P<0.001 in Group B). Compared to pN staging, LNR staging displayed superior performance in prognosis, the adjusted hazard ratio of recurrence being 2.07 (95%CI, 1.07 to 4.0) for intermediate risk group (P=0.030) and 2.44 (95%CI, 1.21 to 4.92) for high risk group (P=0.013) in Group A. Conclusions: LNR stratification proved an adverse prognostic factor of DFS in lymph nodes positive invasive BC using cut-off values 0.20 and 0.65, and was more predictive than traditional pN classification for 5-DFS.