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      • KCI등재

        Rock-breaking analysis model of new drill bit with tornado-like bottomhole model

        Jia-lin Tian,Chang-fu Yuan,Lin Yang,Chuan-hong Fu,Gang Liu,Zhi Yang,Chun-ming Wu 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.4

        For improving the rock-breaking efficiency of oil and gas drill bits, a new drill bit is presented with tornado-like bottomhole model(named swirling cutting bit). The new drill bit cutter breaks rock with shocking and cutting effect during the drilling process, and theelements on largest ring cross the borehole center with high speed. It can effectively improve the center rock-breaking efficiency. Meanwhile,for all cutters on different rings breaking rock at the same time, it can optimize the rock-breaking volume of each element andimprove the bit service life. To analyze the interaction features between cutters and rock, the position equations are established by thecylindrical coordinates and complex movement principles, and then the velocity and acceleration equations can be obtained. Based on thenumerical example results, this paper analyzes the bottomhole model, the contact section, and the distribution features of velocities andaccelerations on different rings. By analyzing the acceleration results, we can study the failure mechanism of cutters. At the same time,lab experiments test the bottomhole model and rock-breaking features, and it verifies the accuracy of calculation method and equations. Moreover, the analysis method and models are also applicable to other types of bits or composite bits, and the inputting parameters needcorresponding adjustment for different type of bits.

      • KCI등재

        Catalytic ozonation of methylene blue in aqueous solution by loading transition metal(Co/Cu/Fe/Mn) on carbon

        Fu-Huang Lin,Minghan Luo,Longzhe Cui,Gui-Ping Wu 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.2

        Activated carbon(AC) was prepared using brewing yeast as a precursor by chemical activation; meanwhile,cobalt, copper, ferrum and manganese supported on activated carbon(Co/AC, Cu/AC, Fe/AC, Mn/AC) were preparedby adsorption-activation method. The characterizations of prepared AC, Co/AC, Cu/AC, Fe/AC, Mn/AC and theirperformance as ozonation catalysts were tested. The total BET surface areas of prepared AC, Co/AC, Cu/AC, Fe/AC,Mn/AC were found to be 957.7, 789.7, 485.3, 486.1 and 529.8m2/g. Absorption capacities of methylene blue (MB) weredetermined to 407.77, 206.52, 121.25, 123.01, 170.94mg/g, respectively. The presence of AC was advantageous for TOCreduction of MB compared with UV/O3 system, and metal Co, Cu, Fe, Mn play an important role in the degradationprocess. The greatest TOC removal efficiency was obtained in the presence of Co/AC.

      • KCI등재

        Phase transition, dielectric and piezoelectric properties of NaNbO3-Bi0.5Li0.5TiO3 lead-free ceramics

        Lingling Fu,Dunmin Lin,Qiaoji Zheng,Xiaochun Wu,Lang Wu,Hailing Sun,Yang Wan,Ximing Fan,Chenggang Xu 한국물리학회 2012 Current Applied Physics Vol.12 No.6

        Lead-free ceramics (1-x)NaNbO3-xBi0.5Li0.5TiO3 have been fabricated by an ordinary sintering technique,and their electric properties and temperature characteristics have been studied. All the ceramics possess a perovskite structure with orthorhombic symmetry, indicating that (Bi0.5Li0.5)TiO3 diffuses into NaNbO3 lattices to form a new solid solution. A low (Bi0.5Li0.5)TiO3 doping level transforms the NaNbO3ceramics from antiferroelectric to ferroelectric. The ceramics with x ≤ 0.075 are normal ferroelectric, and the ferroelectric-paraelectric phase become diffusives with the doping level of Bi0.5Li0.5TiO3 increasing. As x increases, the Curie temperature of the ceramics decreases linearly, while the relative permittivity εr increases. 0.925NaNbO3e0.075(Bi0.5Li0.5)TiO3 ceramic exhibits the relatively large piezoelectric constant (d33 = 58 pC/N), high Curie temperature (TC = 228 ℃) and good temperature stability, suggesting that the ceramics are one of new possible candidates for lead-free piezoelectric materials. Lead-free ceramics (1-x)NaNbO3-xBi0.5Li0.5TiO3 have been fabricated by an ordinary sintering technique,and their electric properties and temperature characteristics have been studied. All the ceramics possess a perovskite structure with orthorhombic symmetry, indicating that (Bi0.5Li0.5)TiO3 diffuses into NaNbO3 lattices to form a new solid solution. A low (Bi0.5Li0.5)TiO3 doping level transforms the NaNbO3ceramics from antiferroelectric to ferroelectric. The ceramics with x ≤ 0.075 are normal ferroelectric, and the ferroelectric-paraelectric phase become diffusives with the doping level of Bi0.5Li0.5TiO3 increasing. As x increases, the Curie temperature of the ceramics decreases linearly, while the relative permittivity εr increases. 0.925NaNbO3e0.075(Bi0.5Li0.5)TiO3 ceramic exhibits the relatively large piezoelectric constant (d33 = 58 pC/N), high Curie temperature (TC = 228 ℃) and good temperature stability, suggesting that the ceramics are one of new possible candidates for lead-free piezoelectric materials.

      • KCI등재

        Vibration analysis of new drill string system with hydro-oscillator in horizontal well

        Jia-lin Tian,Zhi Yang,You Li,Lin Yang,Chun-ming Wu,Gang Liu,Chang-fu Yuan 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.6

        With the growth of oil and gas resource demand, the hydro-oscillator is widely used to enhance the Rate of penetration (ROP) and improve the efficacy in drilling various wells. The vibration model is the key issue of dynamics analysis and optimization of downhole tools. For the vibration analysis of the new drill string system with hydro-oscillator in the horizontal well, based on the design of the new hydro-oscillator and its operation conditions, the kinematics expressions are presented. Combined with the vibration force calculation results of the hydro-oscillator, the dynamics model of the new drill string system is established. Furthermore, the important features of vibration frequency, displacement, velocity and acceleration are discussed in the numerical example calculation results. By comparing the results of the calculation and experiment test, we can verify the correctness of the analysis model. With the hydro-oscillator vibration effect, the static friction between the drill string and wellbore is changed to the dynamic friction, so it can result in a significant increase in run length. At the same time, the ROP can be enhanced with the vibration effect. Moreover, with the parameters’ adjustment according to the operation conditions, the analysis method and model can also provide references to the study of similar downhole tools dynamics or mechanical properties.

      • Experimental Study of Factors Affecting the 7075 Aluminum Alloy Thin-walled Parts Milling Force

        Fengyun Yu,Lin Wu,Yunliang Fu,Yanyan Guo,Can Zhao,Xufeng Wang 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.8

        Taking 7075 aluminum alloy thin-walled part as the research object, with higher cutting parameters than the normal value selected, a four factors and four levels orthogonal experiment was carried out, in which we chose YG carbide cutting tools for the milling, intercepted the milling force stable section, selected ten peak values and took an average, conducted multiple linear regression analysis using Matlab numerical calculation software and established the milling force empirical formula of 7075 aluminum alloy thin-walled part to study the factors which have influence on its milling force. By range analysis of the experimental results, the cutting force change rule in the manufacturing process of aluminum alloy with the change of cutting parameter was revealed. It is found that the axial cutting depth had the greatest influence on the force perpendicular to the direction of cutting surface, and the radial cutting depth had the minimal impact. By comparative analysis on theoretical value and experimental value of milling forces, we found that the predicted value of the milling force Fx and Fy in theory were in good agreement with the experimental results with a relative error less than 8.7%. Under the experimental conditions, the optimal milling parameters are axial cutting depth of 2mm, radial cutting depth of 0.5mm, feed speed 95mm/min and cutting speed of 23.86m/min. It will provide data and experiment support for milling of thin-walled parts of similar materials, which will have important practical value and theoretical significance for engineering.

      • Serum Peroxiredoxin3 is a Useful Biomarker for Early Diagnosis and Assessemnt of Prognosis of Hepatocellular Carcinoma in Chinese Patients

        Shi, Liang,Wu, Li-Li,Yang, Jian-Rong,Chen, Xiao-Fei,Zhang, Yi,Chen, Zeng-Qiang,Liu, Cun-Li,Chi, Sheng-Ying,Zheng, Jia-Ying,Huang, Hai-Xia,Yu, Fu-Jun,Lin, Xiang-Yang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.7

        Background: Recently, peroxiredoxin3 (PRDX3) was identified as a novel molecular marker for the progression of hepatocellular carcinoma (HCC). However, its potential clinical application as a serum marker for the early diagnosis and prognosis of HCC has not been investigated. Methods: PRDX3, alpha-fetaprotein (AFP), and other biochemical parameters were measured in serum samples from 297 Chinese patients, including 96 with HCC, 98 with liver cirrhosis (LC), and 103 healthy controls (HCs). Correlations between serum PRDX3 expression and clinicopathological variables and the relationship between serum PRDX3 expression and prognosis were analyzed. Results: Serum PRDX3 was significantly higher in HCC patients than in the LC and HC groups. The sensitivity and specificity of serum PRDX3 for the diagnosis of HCC were 85.9% and 75.3%, respectively, at a cutoff of 153.26 ng/mL, and the area under the curve was 0.865. Moreover, serum PRDX3 expression was strongly associated with AFP level, tumor diameter, TNM stage, and portal vein invasion. Kaplan-Meier curve analysis revealed that HCC patients with high serum PRDX3 expression had a shorter median survival time than those with low PRDX3 expression. Moreover, serum PRDX3 expression was an independent risk factor for overall survival. The inverse correlation between serum PRDX3 and patient survival remained significant in patients with early-stage HCC and in those with normal serum AFP levels. Conclusions: Serum PRDX3 can be used as a noninvasive biomarker for the diagnosis and/or prognosis of HCC.

      • SCIESCOPUSKCI등재
      • KCI등재

        Application of physical vapor deposition process to modify activated carbon fibers for ozone reduction

        Yu-Chih Lin,Chung-Liang Chang,Tser-Sheng Lin,Hsunling Bai,Ming-Gu Yan,Fu-Hsiang Ko,Chia-Tien Wu,Cheng-Hsiung Huang 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.3

        This study utilized the activated carbon fiber (ACF) modified with metal catalyst via physical vapor deposition (PVD) process (ACF/PVD) to diminish ozone. Furthermore, the ozone removal efficiency of ACF/PVD was compared with that of original ACF and ACF modified with metal catalyst via impregnation process (ACF/impregnation). In addition to the kinds of coated metal and the inlet ozone concentrations, the effects of the coating thickness and the reaction temperature on ACF/PVD for ozone removal were also examined. The results indicate that the ozone removal efficiency of ACF/PVD is better than that of original ACF and ACF/impregnation. The ozone removal efficiency of different metal-coated ACF/PVD in the superior order is gold (Au), and manganese (Mn). The increase of Au-coated thickness (3 nm to 80 nm) on ACF/PVD will enhance the ozone removal. However, when the Mn-coated thickness on ACF/PVD is larger than 15 nm, the ozone removal efficiency displays a declining trend. Furthermore, a higher reaction temperature will result in a better ozone removal of ACF/PVD and the original ACF.

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