检索结果-南通市图书馆

NUMERICAL ANALYSIS OF THE INFLUENCE OF THE TIP CLEARANCE FLOWS ON THE UNSTEADY CAVITATING FLOWS IN A THREE- D IMENSIONAL INDUCER

引用

Journal of Hydrodynamics 2009年第1期21卷 34-40页

作者： okita k. UGAJIN H. MATSUMOTO Y. RIk.N Saitama 351-0198 Japan IHI Corporation Yokohama 235-8501 Japan Department of Mechanical Engineering The University of TokyoTokyo 113-8656 Japan

To clarify the influences of the tip clearance flows on the unsteady cavitating flow, the three-dimensional unsteady cavitating flows through both the two-dimensional cascades and the three-dimensional inducer with and without tip clearance are performed numerically. The governing equations for the compressible fluid flow with the DES turbulence model are employed with the assumption of the isentropic process of liquid phase. The evolution of cavities is represented as the source/sink.of vapor phase. The basic equations in the curve linear coordinate are solved by the finite difference method. As the results of the three-dimensional cavitating flows through the two-dimensional cascades, the tip clearance flows from the pressure side to the suction side of the blade produces the tip vortex cavitation, which affects the sheet cavitation on the leading edge of the next blade and enhances the block.ge effect near the casing than the flows without tip clearance. On the other hand, in the case of the three-dimensional inducer, the large back.low cavitation is observed around the inlet of the inducer, where the cavities are developed on the casing by the tip clearance flows. The large pressure gradient between the non-cavitating pressure side and the cavitating suction side enhances the tip clearance flows. The calculation considering the tip clearance reproduces the developed cavitation region similar to that of experimental visualizations. Additionally, the back.low cavitation rotates with the speed slower than the rotation speed of the inducer. Then, the rotation of back.low cavitation causes the periodic fluctuation of the outlet pressure greater than that of the inlet pressure.

关键词： cavitation inducer tip clearance flow numerical analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Magnetic Field Structure and Induced Electric Current Distribution on a Cylindrical Model： Application to Magnetic Nerve Stimulation

引用

Chinese Physics Letters 2009年第7期26卷 115-118页

作者： Taishi okita and Toshiyuk. Tak.gi Institute of Fluid Science Tohoku University Aoba-ku Sendai 980–8577 Japan

We study the relation between the magnetic field structure and the induced electric-current distribution based on a cylindrical model composed of a uniform electrically conductive medium. When the time-varying magnetic fields are axisymmetrically applied in the axial direction of the model, the electric fields are induced around the central axis in accordance with Faradays law. We examine the eddy-current distributions generated by loop-coils with various geometries carrying an alternating electric current. It is shown that the radial structure of the induced fields can significantly be controlled by the loop coil geometry, which will be suitable for practical use especially in magnetic nerve stimulation on bioelectromagneties, if we appropriately p/ace the exciting coil with optimum geometry.

关键词： Mathematical physics Accelerators beams and electromagnetism Medical physics Biological physics

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Analytical Solutions of Electromagnetic Fields from Current Dipole Moment on Spherical Conductor in a Low-Frequency Approximation

引用

Communications in Theoretical Physics 2010年第1期53卷 149-155页

作者： Taishi okita Toshiyuk. Tak.gi Institute of Fluid Science Tohoku University

We analytically derive the solutions for electromagnetic fields of electric current dipole moment, which is placed in the exterior of the spherical homogeneous conductor, and is pointed along the radial direction. The dipole moment is driven in the low frequency f = 1 k.z and high frequency f = 1 GHz regimes. The electrical properties of the conductor are appropriately chosen in each frequency. Electromagnetic fields are rigorously formulated at an arbitrary point in a spherical geometry, in which the magnetic vector potential is straightforwardly given by the Biot- Savart formula, and the scalar potential is expanded with the Legendre polynomials, tak.ng into account the appropriate boundary conditions at the spherical surface of the conductor. The induced electric fields are numerically calculated along the several paths in the low and high frequeny excitation. The self-consistent solutions obtained in this work.will be of much importance in a wide region of electromagnetic induction problems.

关键词： Eddy magnetic induction

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

EFFECT OF GREEN ROOF AGE ON RUNOFF WATER QUALITY IN PORTLAND,OREGON

引用

Journal of Green Building 2018年第2期13卷 42-54页

作者： Jarrett okita Cara Poor Jessica M.k.eiss Ted Eck.ann University of Portland Shiley School of Engineering5000 N Willamette BlvdPortlandOR 97203 Lewis and Clark.College Department of Environmental Studies0615 S.W.Palatine Hill RdPortlandOR 97219 University of Portland Department of Environmental StudiesBuckley Center 2135000 N Willamette BlvdPortlandOR 97203

Green roofs have become a common method to increase water retention on-site in urban ***,the long-term water quality of runoff from green roofs is poorly *** study evaluated the water quality of stormwater runoff from a regular(non-vegetated)roof,a green roof installed 6 months previously,and a green roof installed 6 years ago in Portland,*** of runoff were tak.n during every rain event for 10 months,and analyzed for total phosphorus(TP),phosphate(PO_(4)^(3-)),total nitrogen(TN),nitrate(NO_(3)^(-)),ammonia(NH_(3)),copper(Cu),and zinc(Zn).Runoff from the green roofs had higher concentrations of TP and PO_(4)^(3-)and lower concentrations of Zn compared to the regular *** TP concentrations from the 6-year old roof and 6-month old roof were 6.3 and 14.6 times higher,respectively,than concentrations from the regular roof,and average PO_(4)^(3-)concentrations from the 6-year old roof and 6-month old roof were 13.5 and 26.6 times higher,respectively,compared to the regular *** from the 6-month old green roof had higher concentrations of TP and PO_(4)^(3-)than the 6-year old green roof during the wet season,but lower concentrations during the dry *** 6-month old green roof installations where receiving waters are sensitive or impaired may need additional treatment methods to reduce phosphorus *** green roofs age,water retention decreases and phosphorus leaching increases during the dry season.

关键词： aging and green roofs long term impact of green roofs concentrations of zinc copper phosphorous and phosphate in green roof stormwater runoff soil moisture water quality

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Invasive ductal carcinoma of the pancreas showing exophytic growth

引用

Hepatobiliary & Pancreatic Diseases International 2009年第1期8卷 97-102页

作者： Yuichi Sanada k.zuhiro Yoshida Masaok. Itoh Rik. okita Morihito Ok.da Department of Surgical Oncology Research Institution for Radiation Biology and MedicineHiroshima University

BACk.ROUND:Invasive pancreatic carcinoma generally appears as poorly defined mass reflecting the infiltrative *** aimed to identify the histological and immunohistochemical features in a rare case of pancreatic carcinoma showing exophytic growth. METHODS:A 67-year-old woman presented with a mass of 5.0 cm in diameter in the pancreatic *** computed tomography revealed a well-demarcated, primarily solid mass with a central low-density area. Magnetic resonance cholangiopancreatography revealed neither encasement nor dilation of the main pancreatic *** incorrect preoperative diagnosis was made of solid pseudopapillary tumor of the *** serum carcinoembryonic antigen(CEA)levels and abnormal FDG positron emmission tomography accumulation suggested that the tumor had malignant potential requiring a pancreatoduodenectomy. RESULTS:The head of the pancreas contained a well- circumscribed encapsulated mass of 5.0 cm in diameter, comprising 50%adenocarcinoma,with mucinous carci- noma in the center and anaplastic carcinoma at the *** anaplastic carcinoma comprised pleo- morphic cells(PCs)and pleomorphic giant cells(PGCs). The PGCs phagocytozed mononuclear PCs and lymphocytes adjacent to the capsule without infiltrating the capsule *** revealed that the anaplastic carcinoma cells including PGCs were positive for the tumor antigen Mucin 1 and CEA but negative for vimentin. CONCLUSION:Our observations suggest anaplastic carcinoma components in the present tumor have a ductal origin and that the exophytic tumor growth is associated with the phagocytotic activity of PGCs.

关键词： pancreatic carcinoma anaplastic carcinoma mucinous carcinoma Mucin 1 carcinoembryonic antigen

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Vascular endothelial growth factor 165b expression in stromal cells and colorectal cancer

引用

World Journal of Gastroenterology 2011年第44期17卷 4867-4874页

作者： Mak.to Tayama Tomohisa Furuhata Yoshik. Inafuk. k.nji okita Toshihik. Nishidate Toru Mizuguchi Yasutoshi k.mura k.ichi Hirata the First Department of Surgery Sapporo Medical University

AIM:To characterize the implications of vascular endothelial growth factor(VEGF)-A in stromal cells and colorectal cancer and the expression of VEGF-A splice ***:VEGF-A expression in tumor and stromal cells from 165 consecutive patients with colorectal cancer was examined by *** association between VEGF-A expression status and clinicopathological factors was *** freshfrozen samples were obtained for laser capture microdissection to analyze the splice variants of ***:VEGF-A was expressed in 53.9% and 42.4% of tumor and stromal cells,***-A expression in tumor cells(t-VEGF-A) was associated with advanced clinical stage(stage 0,1/9;stage 1,2/16;stage 2,32/55;stage 3,38/66;stage 4,16/19,P k.factors of recurrence showed that only s-VEGF-A expression was an independent risk.factor for recurrence(relative risk.0.309,95% confidence interval 0.141-0.676,P = 0.0033).The five-year disease-free survival(DFS) rates of t-VEGF-A-positive and-negative cases were 51.4% and 62.9%,*** was no significant difference in t-VEGF-A expression *** five-year DFS rates of s-VEGF-A-positive and-negative cases were 73.8% and 39.9%,respectively.s-VEGFA-positive cases had significantly better survival than s-VEGF-A-negative cases(P = 0.0005).Splice variant analysis revealed that t-VEGF-A was mainly composed of VEGF165 and that s-VEGF-A included both VEGF165 and *** cases with no venous invasion(v0),the level of VEGF165b mRNA was significantly higher(v0 204.5 ± 122.7,v1 32.5 ± 36.7,v2 2.1 ± 1.7,P = 0.03).The microvessel density tended to be lower in cases with higher VEGF165b mRNA ***:s-VEGF-A appears be a good prognostic factor for colorectal cancer and includes VEGF165 and VEGF165b.

关键词： Colorectal cancer Vascular endothelial growth factor-A Vascular endothelial growth factor 165 Microvascular density Stromal cell

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Clinical relevance of increased serum preneoplastic antigen in hepatitis C-related hepatocellular carcinoma

引用

World Journal of Gastroenterology 2020年第13期26卷 1463-1473页

作者： Satoyoshi Yamashita Ak.ra k.to Toshitak. Ak.tsuk. Tak.shi Sawada Tomohide Asai Noriyuk. k.yama k.wamu okita Department of Gastroenterology and Hepatology Japan Community Health Care Organization Shimonoseki Medical CenterShimonosekiYamaguchi 7500061Japan Department of Physiology Faculty of MedicineSaitama Medical UniversityIruma-gunSaitama 3500495Japan Research and Development Division Sekisui Medical Company LimitedRyugasakiIbaraki 3010852Japan Clinical Research Department Eidia Company LimitedChiyoda-kuTokyo 1010032Japan Eisai Company Limited Shinjuku-kuTokyo 1600812Japan Department of Internal Medicine Shunan Memorial HospitalKudamatsuYamaguchi 7440033Japan

BACk.ROUND The prognosis of hepatocellular carcinoma(HCC)patients remains poor despite advances in treatment modalities and *** is important to identify useful mark.rs for the early detection of HCC in *** antigen(PNA),originally reported in a rat carcinogenesis model,is increased in the tissues and serum of HCC *** To determine the diagnostic value of PNA for discriminating HCC and to characterize PNA-positive *** Patients with hepatitis C virus(HCV)-related hepatic disorders were prospectively enrolled in this study,which included patients with hepatitis,with cirrhosis,and with HCC.A novel enzyme-link.d immunosorbent assay was developed to measure serum PNA concentrations in *** Serum PNA concentrations were measured in 89 controls and 141 patients with HCV infections(50 hepatitis,44 cirrhosis,and 47 HCC).Compared with control and non-HCC patients,PNA was increased in *** receiver operating characteristic curve analysis,the sensitivity of PNA was similar to the HCC mark.rs des-γ-carboxy-prothrombin(DCP)andα-fetoprotein(AFP),but the specificity of PNA was *** was no correlation between PNA and AFP and a significant but weak.correlation between PNA and DCP in HCC ***,the correlations with biochemical mark.rs were completely different for PNA,AFP,and DCP;glutamyl transpeptidase was highly correlated with PNA,but not with AFP or DCP,and was significantly higher in PNA-high patients than in PNA-low patients with HCV-related *** PNA may have the potential to diagnose a novel type of HCC in which glutamyl transpeptidase is positively expressed but AFP or DCP is weak.y or negatively expressed.

关键词： Serum preneoplastic antigen Hepatitis C virus Hepatocellular carcinoma Des-γ-carboxy-prothrombin α-Fetoprotein Sensitivity Specificity

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chlorine Atom Transfer of Unactivated Alk.l Chlorides Enabled by Zirconocene and Photoredox Catalysis

引用

Precision Chemistry 2023年第2期1卷 112-118页

作者： Toshimasa okita k.zuhiro Aida k.isuk. Tanak. Eisuk. Ota Junichiro Yamaguchi Department of Applied Chemistry Waseda UniversityShinjukuTokyo 162-0041Japan

Alk.l chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical *** modern photochemical strategies have greatly enhanced the utility of alk.l chlorides as radical precursors,these methods often depend on strongly reducing conditions leading to unproductive side ***,we report a catalytic radical generation from 1°,2°,and 3°unactivated alk.l chlorides with zirconocene and photoredox catalysis,which enables both hydrogenation and borylation on a range of structurally complex *** mild zirconocene-catalyzed protocol shows that zirconium can render the C−Cl bond cleavage more exergonic and can lower the activation energy of the transition state,amplifying the ability of metallocenes toward halogen atom transfer.

关键词： Zirconocene Alk.l chloride Halogen atom transfer Borylation Photoredox catalysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Prognostic roles of preoperative α-fetoprotein and des-γ-carboxy prothrombin in hepatocellular carcinoma patients

引用

World Journal of Gastroenterology 2015年第16期21卷 4933-4945页

作者： Mak.to Meguro Toru Mizuguchi Toshihik. Nishidate k.nji okita Masayuk. Ishii Shigenori Ota Tomomi Uek. Emi Ak.zuk. k.ichi Hirata Department of Surgery Surgical Oncology and ScienceSapporo Medical University School of Medicine

AIM:To clarify the utility of using des-γ-carboxy prothrombin(DCP)andα-fetoprotein(AFP)levels to predict the prognosis of hepatocellular carcinoma(HCC)in patients with hepatitis B virus(HBV)and the hepatitis C virus(HCV)***:A total of 205 patients with HCC(105patients with HBV infection 100 patients with HCV infection)who underwent primary hepatectomy between January 2004 and May 2012 were enrolled *** AFP and DCP levels were used to create interactive dot diagrams to predict recurrence within 2 years after hepatectomy,and cutoff levels were *** in the HBV and HCV groups were classified into three groups:a group with low AFP and DCP levels(LL group),a group in which one of the two parameters was high and the other was low(HL group),and a group with high AFP and DCP levels(HH group).Liver function parameters,the postoperative recurrence-free survival rate,and postoperative overall survival were compared between *** survival curves were compared by logrank.test using the k.plan-Meier *** analysis using a Cox forward stepwise logistic regression model was conducted for a ***:The preoperative AFP cutoff levels for recurrence within 2 years after hepatectomy in the HBV and HCV groups were 529.8 ng/m L and 60 m AU/m L,respectively;for preoperative DCP levels,the cutoff levels were 21.0 ng/m L in the HBV group and 67 m AU/m L in the HCV *** HBV group was significantly different from the other groups in terms of vascular invasion,major hepatectomy,volume of intraoperative blood loss,and surgical *** differences were found between the LL group,the HL group,and the HH group in terms of both mean disease-free survival time(MDFST)and mean overall survival time(MOST):64.81±7.47 vs 36.63±7.62 vs 18.98±6.17mo(P=0.001)and 85.30±6.55 vs 59.44±7.87 vs46.57±11.20 mo(P=0.018).In contrast,the HCV group exhibited a significant difference in tumor size,vascular invasion,volu

关键词： Hepatocellular carcinoma Hepatitis B Hepatitis C Des-γ-carboxy prothrombin α-fetoprotein

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于快慢相位振荡器耦合系统的呼吸网络模型

基于快慢相位振荡器耦合系统的呼吸网络模型

引用

作者： okita TAk.YUk. 上海交通大学

学位级别：硕士

本文提出了一种快和慢相位振荡器相结合的耦合系统。通过该耦合系统的数值模拟,直接观察到两步跃迁到准周期运动的现象,并结合Ott-Antonsen ansatz方程导出低维方程的序参数。通过比较耦合系统的模拟结果和简化后的低维方程,来检查ansat... 详细信息

本文提出了一种快和慢相位振荡器相结合的耦合系统。通过该耦合系统的数值模拟,直接观察到两步跃迁到准周期运动的现象,并结合Ott-Antonsen ansatz方程导出低维方程的序参数。通过比较耦合系统的模拟结果和简化后的低维方程,来检查ansatz方程的适用性。在基础上,本文深入研究并得出几个有趣的结论,这其中快和慢相位振荡器之间的相互作用发挥了关键性作用。由于与慢相位振荡器在某个参数范围内的兴奋性相互作用,快相位振荡器呈现间歇性的出现。而慢相位振荡器由于与快相位振荡器的相互作用,出现了振荡器死亡现象。其主要原因在于使用快相位振荡器的时间平均法而建立的简单相位方程中,出现鞍结点分支的结果。最后,我们展示了在慢相位和快相位振荡器之间的1:m阶的宏观同步现象。

关键词：数值计算计算机模拟呼吸无意识昼夜节律神经元星形胶质细胞振荡器相互作用同步建模

来源：

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：