检索结果-南通市图书馆

中国有色金属学会会刊：英文版 2009年第B9期19卷 114-118页

作者： hyun-Seok TAk Chang-Seung HA Dong-hyun kIM Ho-Jun LEE Hae-june LEE Myung-Chang kANG National Core Research Center for Hybrid Materials Solution Pusan National University Department of Electrical Engineering Pusan National University

WC-Co is used widely in die and mold industries due to its unique combination of hardness, strength and wear-resistance. For machining difficult-to-cut materials, such as tungsten carbide, micro-electrical discharge machining(EDM) is one of the most effective methods for making holes because the hardness is not a dominant parameter in EDM. This paper describes the characteristics of the discharge conditions for micro-hole EDM of tungsten carbide with a WC grain size of 0.5 μm and Co content of 12%. The EDM process was conducted by varying the condenser and resistance values. A R-C discharge EDM device using arc erosion for micro-hole machining was suggested. Furthermore, the characteristics of the developed micro-EDM were analyzed in terms of the electro-optical observation using an oscilloscope and field emission scanning electron microscope.

关键词：电火花加工碳化钨钴难切削材料硬质合金放电扫描电子显微镜微孔模具行业

Performance Analyses for a Cyclone Type Filter

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2015年第3期24卷 290-294页

作者： Hyoung-june kim Masahiro Takei hyun Jin Lee Yeon Won Lee Yoon Hwan Choi Deog-Hee Doh School of Mechanical Engineering Artificial Science Division Chiba University Division of Mech. and Energy Systems Eng. korea Maritime University Dept. of Mechanical and Automotive Engineering Pukyong National University

Flow characteristics inside a cyclone filter were investigated by the use of computational fluid dynamics(CFD). For computations, SST model was adopted. parametric study was carried out considering the filtering performance. Revolution speeds were changed from 100 to 550 with 50 increments. A skirt is the driving source for cyclone operation. The influence of several design factors, such as the skirt length, the skirt gap and the return length to filtering performance was investigated under the particle diameter 100μm of debris material(Al, s.g.=2.7). The filtering performance was also investigated with the skirt length 28 mm changing the debris diameters from 1μm to 50μm. The flow rate of the working fluid was maintained at 0.55kg/s. It has been verified that the most influential factors to the filtering efficiencies was the skirt gap between the cyclone generator and the cyclone vessel.

关键词： CFD cyclone filter design factors filtering performances

[001]-texturing of(k,Na)NbO_(3)-based piezoceramics with a pseudocubic structure and their application to piezoelectric devices

在线全文

学校读者我要写书评

暂无评论

Journal of Materiomics 2024年第3期10卷 632-642页

作者： Su-Hwan Go Seok-Jung pa.k Seung-hyun kim Seok-june Chae Eun-Ji kim Geun-Su Lee Sahn Nahm Department of Materials Science and Engineering Korea UniversitySeoul02841Republic of Korea

0.96(k_(0.5)Na_(0.5-z)Li_(z))(Nb_(0.92)Sb_(0.08))O_(3)-0.04(Ca_(0.5)Sr_(0.5))ZrO_(3)[(kN_(0.5-z)L_(z))NS-CSZ]piezoceramics(0≤z≤0.04)were aligned in the[001]orientation using 3%(in mole)NaNbO_(3)templates with a large Lotgering factor(>97%).Their crystal structures transformed from the orthorhombic-pseudocubic(O-P)structure to the orthorhombic-tetragonal-pseudocubic(O-T-P)structure with an increasing *** P structure was interpreted as a rhombohedral R3m *** piezoelectricity of the compositions increased after[001]-texturing,and the enhancement was proportional to the O phase *** composition(z=0.03)exhibited the highest piezoelectric constant(d_(33);670 pC/N)and electromechanical coupling factor(k_(p);0.56).Piezoelectric energy harvesters were produced using the untextured and textured samples(z=0.03).The textured harvester delivered a large power density of 26.6 mW/mm^(3),which was larger than that of the untextured harvester owing to the enhanced kp and d_(33)×g_(33) of the textured piezoceramic.A multilayer actuator was produced using the textured sample(z=0.03),and it exhibited a large acceleration(44.2 G)and displacement(±3,730 mm)at±25 ***,the[001]-textured(kN_(0.47)L_(0.03))NS-CSZ piezoceramic is suitable for piezoelectric energy harvesters and actuators.

关键词： kNN-Based piezoceramic Lead-free Energy harvester Actuator Reactive template grain growth

Durability of viral response after off-treatment in HBeAg positive chronic hepatitis B

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2012年第43期18卷 6277-6283页

作者： Myeong Jun Song Do Seon Song Hee Yeon kim Sun Hong Yoo Si hyun Bae Jong Young Choi Seung kew Yoon Yong-Han pa.k june Sung Lee hyun Woong Lee hyung Joon kim Departments of Internal Medicine College of Medicine The Catholic University of Korea Seoul 137-040 South Korea Departments of Internal Medicine Samsung Medical Center Sungkyunkwan University School of Medicine Seoul 135-710 South Korea Departments of Internal Medicine College of Medicine Inje University Ilsan Paik Hospital of The Korea Goyang-si 411-706 South Korea Departments of Internal Medicine College of Medicine The Chung-Ang University of Korea Seoul 156-755 South Korea

AIM:To evaluate the durability in hepatitis B e antigen (HBeAg) positive chronic hepatitis B patients who discontinued antiviral treatment. METHODS:A total of 48 HBeAg positive chronic hepatitis B patients who were administered nucleoside analogues and maintained virological response for ≥ 6 mo [hepatitis B virus (HBV) DNA patients were followed up at 3-6 mo intervals. The primary endpoint was serologic and virologic recurrence rates after withdrawal of antiviral treatment. Serologic recurrence was defined as reappearance of HBeAg positivity after HBeAg seroconversion. Virologic recurrence was defined as an increase in HBV-DNA level > 104 copies/mL after HBeAg seroconversion with previously undetectable HBV-DNA level. RESULTS:During the median follow-up period of 18.2 mo (range:5.1-47.5 mo) after cessation of antiviral treatment, the cumulative serological recurrence rate was 15 % at 12 mo. The median duration between the cessation of antiviral treatment and serologic recurrence was 7.2 mo (range:1.2-10.9 mo). Of the 48 patients with HBeAg positive chronic hepatitis, 20 (41.6%) showed virological recurrence. The cumulative virologic recurrence rates at 12 mo after discontinuing the antiviral agent were 41%. The median duration between off-treatment and virologic recurrence was 7.6 mo (range:4.3-27.1 mo). The mean age of the virological recurrence group was older than that of the non-recurrence group (46.7 ± 12.1 years vs 38.8 ± 12.7 years, respectively; P = 0.022). Age (> 40 years) and the duration of consolidation treatment (≥ 15 mo) were significant predictive factors for offtreatment durability in the multivariate analysis [P = 0.049, re

关键词： Durability Seroconversion Chronic hepatitis B Hepatitis B e antigen positive Recurrence Consolidation

Relationship between insulin resistance, obesity and serum prostate-specific antigen levels in healthy men

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2010年第3期12卷 400-404,I0011页

作者： june hyun Han Yong Taec Lee kyung Won kwak Seung hyun Ahn In Ho Chang Soon Chul Myung Seung Young Oh Yong-Seong Lee Wonyong kim Young-Woo Jin Tae-In Choi Sook Hee Sung Department of Urology KEPCO Medical Foundation Hanil General Hospital Seou1132-703 Korea Department of Urology Chung-Ang University Hospital Seoul 140-757 Korea Department of Urology Hyundae General Hospital Namyangju 472-865 Korea Department of Urology Hallym University Hangang Sacred Heart Hospital Seoul 150-719 Korea Department of Microbiology College of Medicine Chung-Ang University Seoul 156- 756 Korea Radiation Health Research Institute Korea Hydro ＆ Nuclear Power Co. LTD Seoul 132-703 Korea

The purpose of this study was to determine the relationship between insulin resistance, obesity and serum prostate-specific antigen （PSA） levels in healthy men with serum PSA level below 4 ng mL-1. The men included in the study cohort were 11 827 healthy male employees of the korea Hydro and Nuclear Power Co., LTD who had undergone medical checkups including fasting glucose, fasting insulin and serum PSA between January 2003 and December 2008. Insulin resistance was calculated by homeostasis model assessment （HOMA [fasting glucose × fasting insulin]/22.5） and quantitative insulin sensitivity check index （QUICk/; 1/[log （fasting insulin）＋ log （fasting glucose）]）. Age-adjusted body mass index （BMI） was significantly increased according to increasing quartile of insulin resistance as determined by HOMA and QUICkI, respectively, in analysis of variance （ANOVA） test and Duncan＇s multiple comparison test （P 〈 0.001）, but age-adjusted serum PSA concentration was significantly decreased according to increasing quartile of insulin resistance as determined by HOMA and QUICk/（P 〈 0.001）. Age, BMI, insulin resistance by HOMA or QUICk/were significantly independent variables to serum PSA level in a multivariate linear regression analysis （P 〈 0.001）. Insulin resistance was a significant independent variable to serum PSA level along with BMI. Insulin resistance and BMI were negatively correlated with serum PSA level in healthy men. Insulin resistance was positively correlated with BMI.

关键词： body mass index insulin resistance metabolic syndrome X obesity prostate-specific antigen

Exosome-based strategy against colon cancer using small interfering RNA-loaded vesicles targeting soluble a proliferationinducing ligand

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Stem Cells 2024年第11期16卷 956-973页

作者： hyung-Jin kim Do Sang Lee Jung hyun pa.k Ha-Eun Hong Ho Joong Choi Ok-Hee kim Say-june kim Department of Surgery Eunpyeong St.Mary’s HospitalCollege of MedicineThe Catholic University of KoreaSeoul 03312South Korea Department of Surgery Seoul St.Mary’s HospitalCollege of MedicineThe Catholic University of KoreaSeoul 06591South Korea Catholic Central Laboratory of Surgery College of MedicineThe Catholic University of KoreaSeoul 06591South Korea Translational Research Team Surginex Co.Ltd.Seoul 06591South Korea

BACkGROUND Recent advancements in nanomedicine have highlighted the potential of exosome(Ex)-based therapies,utilizing naturally derived nanoparticles,as a novel approach to targeted cancer *** To explore the targetability and anticancer effectiveness of small interfering peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 RNA(siPIN1)-loaded soluble a proliferation-inducing ligand(sAPRIL)-targeted Exs(designated as tEx[p])in the treatment of colon cancer *** tEx was generated by harvesting conditioned media from adipose-derived stem cells that had undergone transformation using pDisplay vectors encoding sAPRIL-binding peptide ***,tEx[p]were created by incorporating PIN1 siRNA into the tEx using the Exofect *** therapeutic efficacy of these Exs was evaluated using both in vitro and in vivo models of colon *** The tEx[p]group exhibited superior anticancer effects in comparison to other groups,including tEx,Ex[p],and Ex,demonstrated by the smallest tumor size,the slowest tumor growth rate,and the lightest weight of the excised tumors observed in the tEx[p]group(Pkers Vimentin and Snail(Pkely due to the enhanced delivery of *** The use of bioengineered Exs targeting sAPRIL and containing siPIN1 demonstrated superior efficacy in inhibiting tumor growth and epithelial-mesenchymal transition,highlighting their potential as a therapeutic strategy for colon cancer.

关键词： Colon cancer Drug delivery system Exosome Soluble a proliferation-inducing ligand Peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 Targeted therapy

Gyejibokryeong-Hwan improves recovery of injured muscles in mouse model of muscle contusion

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Traditional Chinese Medicine 2021年第3期41卷 406-413页

作者： Chi Ho Lee Jeong june Choi Joo Hye Sim Younmin Shin Seung-Joon Oh Ji-Hyang Gu hyun Ju Ha Dong Hwi Jeon Eun-Jung Lee Min-Seok Oh Department of korean Medicine Rehabilitation College of Korean MedicineDaejeon UniversityDaejeon 34520Republic of Korea Laboratory of Molecular Medicine College of Korean MedicineDaejeon UniversityDaejeon 34520Republic of Korea

OBJECTIVE: To investigate the effects of Gyejibokryeong-Hwan(Guizhifuling-wan, GBH) on muscle injury in a mouse model of muscle ***: C57/BL6 mouse biceps femoris muscles were injured using the drop-mass method and injured animals were treated orally with GBH(50,100, or 500 mg/kg) once a day for 7 d. Open field and treadmill running tests were performed to assess functional recovery from muscle injury. The production of pro-inflammatory cytokines was examined by enzyme-linked immunosorbent assay and Western blotting analysis. Expression of the muscle regeneration biomarkers, myoblast determination(Myo D), myogenic factor 5(Myf5), and smooth muscle actin(α-SMA), in the biceps femoris muscle was investigated at the protein and m RNA level by Western blotting and real time-PCR, respectively. Histological analysis was performed using hematoxylin and eosin staining. Finally, myosin heavy chain production was investigated in differentiated C2C12 myoblasts in the presence of ***: GBH treatment markedly improved locomotion and running behavior. GBH significantly inhibited the secretion of monocyte chemoattractant protein-1 into the bloodstream in muscle-contused animals. The levels of Myo D, Myf5, and α-SMA protein and m RNA were significantly up-regulated by GBH in injured muscle tissue. Histological studies suggested that GBH facilitated recovery from muscle damage. However, GBH did not induce the production of myosin heavy chain in ***: Overall, the present study suggested that GBH improves the recovery of the injured muscles in the mouse model of muscle contusion.

关键词： muscles wounds and injuries contusions regeneration muscle skeletal myogenic regulatory factor 5 Gyejibokryeong-Hwan

Younger patients have poorer biochemical outcome after radical prostatectomy in high-risk prostate cancer

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2011年第5期13卷 719-723页

作者： Sung kyu Hong Jung Soo Nam Woong Na Jong Jin Oh Cheol Yong Yoon Chang Wook Jeong hyun june kim Seok-Soo Byun Sang Eun Lee Department of Urology Seoul National University Bundang Hospital Seongnam Kyunggi-do 463-707 Korea

The aim of this study was to investigate the prognostic significance of patient age with respect to tumour aggressiveness in men who underwent radical prostatectomy （RP） for prostate cancer. In this study, we reviewed the records of 743 patients who received RP without neoadjuvant or adjuvant therapy at our institution and were followed up for 〉2 years postoperatively. For our analyses, the patients were divided into two groups according to age： younger （〈60 years） and older （≥ 60 years）. Through uni- and multivariate analyses, associations of various clinicopathological parameters, including biochemical recurrence-free survival, with patient age, were evaluated among all patients, and the patients were stratified according to their D＇Amico risk classification. Among all subjects, younger （n= 126） and older （n=617） patients showed no significant differences regarding pathological parameters and biochemical recurrence-free survival （P=0.288）. For the high-risk group （n= 206）, younger patients had a lower rate of biochemical recurrence-free survival following surgery than older patients （P=0.017）, despite the fact that no significant differences were observed regarding various known prognostic parameters between the two age groups. In addition, multivariate analysis revealed that age was an independent predictor of biochemical recurrence-free survival among the high-risk group （P=O.O03）. Our results showed that relatively younger patients have a comparable biochemical outcome compared with their older counterparts following RP performed for prostate cancer. However, among patients with high-risk disease, younger patients have a worse biochemical outcome following RP compared with older patients.

关键词： age factors biochemical outcome prostate prostatic neoplasms prostatectomy

Decomposition behavior of yttria-stabilized zirconia and its effect on directed energy deposited Ti-based composite material

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2022年第17期112卷 138-150页

作者： Gwanghyo Choi Won Seok Choi Yoon Sun Lee Dahye kim Ji hyun Sung Seungjun An Chang-Seok Oh Amine Hattal Madjid Djemai Brigitte Bacroix Guy Dirras Pyuck-pa Choi Department of Materials Science and Engineering Korea Advanced Institute of Science and TechnologyDaejeon 34141Republic of Korea 3D Additive Manufacturing Application Tech.Center Korea Institute of Industrial TechnologyDaegu 42994Republic of Korea InssTek Co. Daejeon 04763Republic of Korea korea Institute of Materials Science 797 ChangwondaeroChangwon 51508Republic of Korea UniversitéSorbonne paris Nord Laboratoire des Sciences des Procédés et des MatériauxLSPMCNRSUPR 3407F-93430VilletaneuseFrance Z3Dlab Parc Technologique26 Rue des SablonsMontmagny 95360France CNRS UPR3407Laboratoire des Sciences des Procédés et des MatériauxLSPMUniversitéSorbonne Paris NordF-93430VilletaneuseFrance

We report on the microstructure and the strengthening mechanisms of additively manufactured parts fabricated by directed energy deposition of Ti-6Al-4V(Ti64)powders blended with yttria-stabilized zirconia(YSZ)*** specimens showed refined microstructures as compared to bare as-deposited Ti64,where theαand columnar priorβgrain sizes decreased with increasing YSZ *** YSZ nanoparticles decomposed during the deposition process and led to the formation of yttrium oxide and some excess oxygen in the Ti64 *** decrease in the sizes of the priorβgrains could be attributed to the increasing amount of dissolved oxygen and yttrium,which promoted constitutional ***,the reduction in the size of theαgrains could be ascribed to a shift of the onset of theβ→α+βtransformation to a higher temperature and shorter time with increasing concentration of dissolved ***,the contributions of the underlying strengthening mechanisms for the as-deposited specimens were quantitatively determined.

关键词： Additive manufacturing Directed energy deposition Metal matrix composites Titanium alloys Yttrium-stabilized zirconia

Two-step generation of induced pluripotent stem cells from mouse fibroblasts using Id3 and Oct4

在线全文

学校读者我要写书评

暂无评论

Journal of Molecular Cell Biology 2012年第1期4卷 59-62页

作者： Jai-Hee Moon june Seok Heo Suhyun kwon Jihyun kim Jihye Hwang Phil Jun kang Aeree kim hyun Ok kim kwang Youn Whang Byung Sun Yoon Seungkwon You Laboratory of Cell Function Regulation College of Life Sciences and BiotechnologyKorea UniversitySeoulRepublic of Korea Cell Therapy Center College of MedicineYonsei UniversitySeoulRepublic of Korea Department of pathology College of MedicineKorea University Guro HospitalSeoulRepublic of Korea Division of Biotechnology College of Life Sciences and BiotechnologyKorea UniversitySeoulRepublic of Korea

Dear Editor,Somatic cells can be reprogrammed into pluripotent stem cells,called induced pluripotent stem cells(iPSCs),by defined transcription factors(Takahashi et al.,2006).The reprogramming of somatic cells may be a continuous stochastic process in which nearly all somatic donor cells have the ability to give rise to iPSCs with continuous passaging and the expression of defined factors(Hanna et al.,2009).However,the reprogramming process can be divided into discrete stages,including the generation of dedifferentiated pre-pluripotent cells followed by authentic pluripotent cells(Silva et al.,2009).

关键词： pluripotent programming