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Smagorinsky常数对扁平箱梁气动特性大涡模拟的影响研究

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振动工程学报 2022年第6期35卷 1371-1378页

作者：祝志文刘帅永刘震卿汕头大学土木与环境工程系广东汕头515063 华中科技大学土木工程与力学学院湖北武汉430074

作为大涡模拟(LES)的唯一模型参数,经验Smagorinsky常数(C_(S))与特定的流动条件有关。为研究扁平箱梁气动特性LES的合理C_(S)取值,开展了C_(S)值在0.032~0.7范围以及动态亚格子黏性模型的多工况LES模拟,通过与风洞试验结果的对比,分析... 详细信息

作为大涡模拟(LES)的唯一模型参数,经验Smagorinsky常数(C_(S))与特定的流动条件有关。为研究扁平箱梁气动特性LES的合理C_(S)取值,开展了C_(S)值在0.032~0.7范围以及动态亚格子黏性模型的多工况LES模拟,通过与风洞试验结果的对比,分析了主梁气动特性随C_(S)值的变化。研究认为:C_(S)值不同时主梁表面压力和气动力的平均值差别不明显,其结果也与风洞试验吻合良好;但C_(S)值的变化对主梁表面压力和气动力的均方根(RMS)值影响明显,结果也与风洞试验存在较大差异,C_(S)值增大导致气动力脉动降低甚至无脉动;LES采用动态亚格子黏性模型无法给出主梁涡脱和表面压力的合理估计。在0.064≤C_(S)≤0.27区间,LES均能给出与风洞试验一致的主梁涡脱单频和St值估计;从捕捉流动的非定常特性考虑,建议C_(S)在上述范围内取小值。研究认为,C_(S)增大导致亚格子湍流黏性增大,流动的耗散作用增强,降低了LES对非定常湍流特性的捕捉能力,导致模拟的气动力脉动量减小。

关键词：扁平箱梁大涡模拟气动特性漩涡脱落 Smagorinsky常数

Surgical treatment of Budd-Chiari syndrome:analysis of 221 cases

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Hepatobiliary & Pancreatic Diseases International 2011年第4期10卷 435-438页

作者： Xiao-Wei Dang,Pei-Qin Xu,Xiu-Xian Ma,Da-Qian Xu,Yan-Ju Zhu and yong-shuai Zhang Division of Hepatobiliary and Pancreatic Surgery,First Affiliated Hospital,Zhengzhou University,Zhengzhou 450052,China Division of Hepatobiliary and Pancreatic Surgery First Affiliated Hospital Zhengzhou University Zhengzhou 450052 China

BACKGROUND:Budd-Chiari syndrome (B-CS) refers to post-hepatic portal hypertension and/or inferior vena cava hypertension caused by obstruction of blood flow at the portal cardinal hepatic *** treatments of B-CS include operations on pathological membrane lesions,shunting and combined *** have shown that China,Japan,India and South Africa have a high incidence of *** China,the Yellow River Basin in Henan,Shandong,Jiangsu and Anhui Provinces also have a high incidence,around 10 per 100 ***:The clinical data of 221 B-CS patients were analyzed *** focused on pathological types,surgical methods,effectiveness and complications of treatment,and ***:Based on imaging findings such as color ultrasonography,angiography or magnetic resonance angiography,the 221 patients were divided into 3 types (five subtypes):type Ia (72 patients),type Ib (20),type II (72),type IIIa (33),and type IIIb (24).Surgical procedures included balloon membranotomy with or without stent (65 patients),improved splenopneumopexy (18),radical resection of membrane and thrombus (17),inferior vena cava bypass [29,with cavocaval transflow (13) and cavoatrial transflow (16)],mesocaval shunt (41),splenocaval shunt (25),splenoatrial shunt (12),splenojugular shunt (6),and combined methods (8).The complication rate was 9.05% (20/221) and the perioperative death rate was 2.26% (5/221).All of the patients were followed up from 6 months to 5 *** success rate was 84.6% (187/221),and the recurrence rate was 8.9% (9/101) and 13.5% (13/96) after 1-and 5-year follow-up,***:The rational choice of surgical treatment based on B-CS pathological typing may increase the success rate and decrease the recurrence.

关键词： Budd-Chiari syndrome intervention shunt transflow

Stratigraphic framework and sedimentary evolution during the Cryogenian-Ediacaran transition in northeastern Sichuan Basin,South China

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Petroleum Science 2024年第2期21卷 823-835页

作者： Yi Zhang Hong-Wei Kuang yong-Qing Liu Qiang Shi Dong-Ge Wang Ke-Ning Qi Yu-Chong Wang Da-Wei Qiao Xiao-shuai Chen Li-Zhi Wu Meng Tian Long Chen Yi Wei Liao-Yuan Song Jian Li Zi-Gang Wu Yun-Qian Liu Xuan-Chun Liu An-Qing Chen Zhi-Wei Liao Institute of Geology Chinese Academy of Geological SciencesBeijing100037China State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing400044China No.205 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing401121China Chongqing Institute of Geological Survey Chongqing401122China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu610059SichuanChina

The northeastern Sichuan area in the northern Yangtze margin has unique Ediacaran geological records,especially the Doushantuo Formation(DST),and become a hot research area in recent ***,the Cryogenian-Ediacaran(C-E)boundary has not been precisely identified,which restricts the in-depth study of geological information during this crucial transitional period and is unfavorable for a systematic and complete understanding of the Yangtze Block and even the global paleogeographic *** study conducted stratigraphy,sedimentology,and chronostratigraphy to establish the stratigraphic framework and sedimentary evolution of the C-E transition strata in northeastern *** results showed that the Ediacaran sediments,without the cap dolomite,unconformably overlaid the Cryogenian sediments in the studied *** Member II of the DST,characterized by 50-160 m of red-green sandstone(approximately equivalent to the original Chengkou“Guanyinya Formation”),directly overlaid the Cryogenian sediments and displayed a 623±2.3 Ma maximum depositional age from the detrital zircon U-Pb *** stratigraphic correlations indicate that the C-E transition strata in northeastern Sichuan had a consistent lithological association and sedimentary sequence characteristics but differed from the Three ***,the upper Nantuo massive glacial diamictites transition to the icebergs rafted lonestone-bearing mudstones at the top,then change upward to DST barrier coast *** proposed DST of the northeastern Sichuan Basin was divided into three lithostratigraphic members without the regional Member I cap dolomite:(i)Member II purple-red,gray-green sandstone strata,(ii)MemberⅢblack mudstone strata,and(iii)Member IV P-Mn bearing *** the C-E transition,the study area experienced(i)the global deglaciation stage in the terminal Marinoan glaciation and(ii)the filling-leveling up stage with clastic rocks in the early ***,the early Ediacaran

关键词： Marinoan glaciation Doushantuo formation Cap dolomite Deglacial and coastal deposits Detrital zircon U-Pb dating

Bound-State Soliton Solutions of the Nonlinear Schr?dinger Equation and Their Asymmetric Decompositions

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Chinese Physics Letters 2019年第3期36卷 5-8页

作者：张永帅贺劲松 School of Science Zhejiang University of Science and Technology Institute for Advanced Study Shenzhen University

We study the asymmetric decompositions of bound-state(BS) soliton solutions to the nonlinear Schr?dinger equation. Assuming that the BS solitons are split into multiple solitons with different displacements, we obtain more accurate decompositions compared to the symmetric decompositions. Through graphical techniques, the asymmetric decompositions are shown to overlap very well with the real trajectories of the BS soliton solutions.

关键词： Solutions Nonlinear Equation

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纳滤技术在工业废水处理中的应用

化工设计通讯 2022年第12期48卷 175-177页

作者：陈梅张永帅新疆应用职业技术学院新疆奎屯832000

纳滤(NF)膜由于其独特的特点,如对二价/多价离子的高选择性,同时允许对100Da以下的小分子的渗透,已应用于废水的处理。因此,NF在废水处理中的应用对于工业废水处理中水的回收再利用和其他有价值产品的回收具有广阔的应用前景。基于此,... 详细信息

纳滤(NF)膜由于其独特的特点,如对二价/多价离子的高选择性,同时允许对100Da以下的小分子的渗透,已应用于废水的处理。因此,NF在废水处理中的应用对于工业废水处理中水的回收再利用和其他有价值产品的回收具有广阔的应用前景。基于此,论述了纳滤技术及其分离机理,探讨了NF目前在纺织、食品、石油和天然气、采矿、制革、制药以及纸浆和造纸工业等多个行业的水回收、再利用和产品回收中的应用,最后展望NF在工业废水处理、水循环、再利用和产品回收中的应用前景。

关键词：纳滤技术纳滤膜工业废水处理

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基于RF-BiLSTM模型的河流水质预测

长江科学院院报 2024年第7期41卷 57-63,71页

作者：兰小机贺永兰武帅文江西理工大学土木与测绘工程学院江西赣州341000

水环境中过量的氮、磷和高锰酸盐会对流域造成严重污染,准确预测这三类指标的含量对流域污染治理具有重要意义。然而,现有的模型预测精度低,输入因子的选择缺乏数理依据。基于此,以邕江为研究区域,提出一种RF-BiLSTM的混合网络模型。该... 详细信息

水环境中过量的氮、磷和高锰酸盐会对流域造成严重污染,准确预测这三类指标的含量对流域污染治理具有重要意义。然而,现有的模型预测精度低,输入因子的选择缺乏数理依据。基于此,以邕江为研究区域,提出一种RF-BiLSTM的混合网络模型。该模型具有利用RF算法提取水质指标最优特征和利用BiLSTM模型提取输入数据的时间特征的优势,采用先降维后预测的方式对TN、TP和COD Mn进行预测,并将深度学习中的CNN、LSTM、BiLSTM和RF-LSTM作为基准模型与本研究所提模型作对比研究。研究结果表明,本研究模型预测TN、TP和COD Mn的平均绝对百分比误差(MAPE)分别达到了4.330%、6.781%和7.384%,均低于其他基准模型,预测结果具有较高的准确性和实用性,可为水环境的污染治理提供有效的技术支持。

关键词：水质预测特征选择随机森林双向长短时记忆神经网络深度学习

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应用化工技术五年一贯制专业无机化学课程的教学策略探讨

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化工管理 2022年第32期 11-13页

作者：李婷张永帅新疆应用职业技术学院新疆奎屯833200

应用化工技术是五年一贯制应化专业的重要组成部分,该专业的教育成果直接影响后期学生的发展方向。通过分析影响无机化学课程教学效果因素,从教学设计、教学应用、教学评价三个方面制定无机化学教学策略,并进行评价。结果表明:无机化学... 详细信息

应用化工技术是五年一贯制应化专业的重要组成部分,该专业的教育成果直接影响后期学生的发展方向。通过分析影响无机化学课程教学效果因素,从教学设计、教学应用、教学评价三个方面制定无机化学教学策略,并进行评价。结果表明:无机化学课程教学策略适应于应用化工技术五年一贯制专业学生,能够明显提高学生学习成绩和学习效果。

关键词：应用化工技术五年一贯制无机化学教学策略

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刺山柑乳膏剂提取与制备工艺研究

化工设计通讯 2022年第7期48卷 75-77页

作者：魏丽张永帅新疆应用职业技术学院新疆奎屯833200

类风湿性关节炎(rheumatoid arthritis,RA)是一种很常见的临床免疫系统疾病,然而这种常见疾病却并没有特效药,很长一段时间内只能通过贴剂缓解,直到刺山柑乳膏剂的出现。从刺山柑的药用价值以及其乳膏剂的提取方式、质量检验标准等方面... 详细信息

类风湿性关节炎(rheumatoid arthritis,RA)是一种很常见的临床免疫系统疾病,然而这种常见疾病却并没有特效药,很长一段时间内只能通过贴剂缓解,直到刺山柑乳膏剂的出现。从刺山柑的药用价值以及其乳膏剂的提取方式、质量检验标准等方面具体论述,包括刺山柑的提取与检验的数据,揭示其在治疗领域的巨大作用。分别从刺山柑果实的四种初步处理方式、五种软膏剂提取方式以及五种质量检测方式具体论述了这种药物的制备过程。

关键词：刺山柑乳膏剂提取制备质量检测

Thermophotovoltaic Emitters Based on a One-Dimensional Metallic-Dielectric Multilayer Nanostructures

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Journal of Electronics Cooling and Thermal Control 2014年第1期4卷 39-48页

作者： Samah G. Babiker shuai yong Mohamed O. Sid-Ahmed Xie Ming Department of Engineering Thermophysics School of Energy Science and Engineering Harbin Institute of Technology Harbin China Department of Engineering Thermophysics School of Energy Science and Engineering Harbin Institute of Technology Harbin China Department of Physics Faculty of Education University of the Holy Quran and Islamic Science OmdurmanSudan Department of Physics Faculty of Sciences Sudan University of Science and Technology Khartoum Sudan

In this paper, a one-dimensional multilayer is optimized for potential applications as thermophotovoltaic (TPV) selective emitter. The proposed TPV emitter was fabricated through a magnetron sputtering process by using the radio frequency (RF) magnetron sputtering system. The spectral emittance of the proposed TPV emitter is measured by using spectral transmittance and reflectance measurement system at wavelength from 0.3 μm to 2.5 μm at near-normal incident 8。. The bidirectional reflectance distribution function BRDF is measured by three axis automated scatterometer (TAAS). The effect of the diffraction orders and plane of incidence on the spectral emittance of the proposed TPV emitter is calculated numerically by using the rigorous coupled-wave analysis (RCWA). The emittance spectrum of the proposed TPV selective emitter shows three close to unity emission peaks which are explained by the surface plasmon polariton (SPP), gap plasmon polariton (GPP) and magnetic polariton (MP) excitation. The results show that the proposed emitter has high emittance value in the spectral range of 0.69 emitter, if used as a selective emitter with a low band gap photovoltaic cell (GaSb), would lead to high TPV overall efficiency and high electrical output power.

关键词： Thermophotovoltaic Selective Emitter Rigorous Coupled Wave Analysis (RCWA) A Magnetron