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Numerical simulation for the investment casting process of a large-size titanium alloy thin-wall casing

Progress in Natural Science:Materials International 2018年第4期28卷 520-528页

作者： pan tao Heng Shao Zhijun Ji Hai Nan Qingyan Xu Key Laboratory for Advanced Materials Processing Technology Ministry of Education School of Materials Science and Engineering Tsinghua University Beijing Institute of Aeronautical Materials

To optimize the investment casting process when producing high quality large-size titanium alloy thin-wall components is a time-consuming job due to the complicated metallurgical process. Numerical simulation is a high-efficiency method compared with trial and error, and therefore is introduced to the investment casting process optimization to shorten the new product development cycle and reduce the production cost. In this study, weakly compressible model(WCM) and ununiformed finite difference mesh(UFDM) was developed to reduce the memory consumption and ensure the simulation efficiency. The precision of the WCM and UFDM were verified by numerical simulation of cavity heat convection in a square cavity and hydraulics simulation of centrifugal filling in a transparent cavity. The numerical simulation of the investment casting process of a titanium alloy thin-wall casing under different process conditions was accomplished using a self-developed software, and the distribution characteristics of potential shrinkage defects were predicted. It was found that the predicted defects in the titanium alloy casing matched well with the actual X-ray experimental results. For the components investigated in this paper, more numerical simulation results show that the centrifugal casting process with respect to gravity casting had no obvious improvements in the concentrated shrinkage defects, and the gravity casting process can be more reasonable from the engineering point of view.

关键词： Titanium alloy Investment casting Numerical simulation Finite difference method Non-uniform mesh

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Biosorption and biotransformation of crystal violet by Aeromonas hydrophila DN322p

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Frontiers of Environmental Science & Engineering 2013年第2期7卷 185-190页

作者： tao pan Suizhou REN Jun GUO Meiying XU Guoping SUN School of Bioscience and Bioengineering South China University of Technology Guangzhou 510006 China Guangdong Institute of Microbiology Guangzhou 510070 China Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application Guangdong Institute of Microbiology Guangzhou 510070 China Guangdong Open Laboratory of Applied Microbiology Guangzhou 510070 China State Key Laboratory of Applied Microbiology (Ministry-Guangdong Province Jointly Breeding Base) South China Guangzhou 510070 China

DN322p, an offspring of Aeromonas hydro- phila DN322, has the capacity to adsorb and decolorize triphenylmethane dyes in wastewater simultaneously. As a common triphenylmethane dye, crystal violet （CV） was chosen to test the decolorization characteristics of DN322p. Within 0.5h, the strain DN322p adsorbed a large amount of CV, producing a deep-colored cell pellet and colorless supernatant. The colors of the cell pellet and supematant lightened over time. The supernatant and dichloromethane extract of the cell pellet both showed conspicuous CV and leuco CV （LCV） characteristic absorbance peaks at 590 nm and 260 nm, respectively, in the UV-vis spectral analysis. This finding indicated that the DN322p cells can adsorb the two dyes. A 99% （w/w） decolorization rate was achieved within 2.5 h with shaking at 30℃ for 50mg CV.L-1. High Performance Liquid Chromatography （HPLC） analysis of the dichloromethane extract of the supernatant and cell pellet confirmed that CV was mainly converted into its leuco form. Dead cells had a similar adsorption capacity with living cells. About 90% of CV in the dye solution （50mg-L-1） was removed by autoclaved cells with an optical delnsity at 600 nm （OD600） above 1.0.

关键词： crystal violet decolorization biosorption,biotransformation Aeromonas hydrophila DN322p

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Selection of stable equivalent wavebands for near-infrared spectroscopic analysis of total nitrogen in soil

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Journal of Innovative Optical Health Sciences 2014年第4期7卷 57-65页

作者： Jiemei Chen tao pan Guisong Liu Yun Han Dingxing Chen State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008P.R.China Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Educational Institute Jinan University Guangzhou 510632P.R.China

The selection of stable wavebands for the near-infrared(NIR)spectroscopic analysis of total nitrogen(TN)in soil was accomplished by using an improved moving window partial leastsquares(MWPLS)method.A new modeling approach was performed based on randomness,similarity and stability,which produced an objective,stable and practical *** on the MWPLS method,a search was in the overali scanning region from 400 to 2498 nm,and the optimal waveband was identified to be 1424 to 282 nm.A model space that includes 41 wave-bands that are equivalent to the optimal waveband was then *** public range of the 41equivalent optimal wavebands was 1590 to 1870 nm,which contained suficient TN *** wavebands of 1424 to 2282 nm,1590 to 1870nm,and the long NIR region 1100 to 2498 nmall achieved satisfactory validation ***,the public waveband of 1590 to 1870 nm hadonly a minimum number of wavelengths,which significantly reduced the method *** equivalent wavebands serve as guidelines for designing spect roscopic *** could address the restrictions of position and the number of wavelengths in instru-ment design.

关键词： Soil otal nitrogen near-ifrared spectroscopy improved moving window partial least squares stability

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Endovascular denervation(EDN):From Hypertension to Non-Hypertension Diseases

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Journal of Interventional Medicine 2021年第3期4卷 130-135页

作者： tao pan Qi Zhang Jinhe Guo Center of Interventional Radiology cS Vascular Surgery Department of RadiologyZhongda Hospital Southeast University87 Dingjiaqiao RoadNanjing210009China

Recently,the use of endovascular denervation(EDN)to treat resistant hypertension has gained significant *** addition to reducing sympathetic activity,EDN might also have beneficial effects on pulmonary arterial hypertension,insulin resistance,chronic kidney disease,atrial fibrillation,heart failure,obstructive sleep apnea syndrome,loin pain hematuria syndrome,cancer pain and so *** this article we will summarize the progress of EDN in clinical research.

关键词： Endovascular denervation Resistant hypertension Sympathetic activity Clinical research

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Age and Body Size of the Shangcheng Stout Salamander Pachyhynobius shangchengensis(Caudata:Hynobiidae)from Southeastern China

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Asian Herpetological Research 2020年第3期11卷 219-224页

作者： Jianli XIONG Jianping GOU Yong HUANG Baowei ZHANG Hongtao REN tao pan College of Animal Science and Technology Henan University of Science and TechnologyLuoyang 471023HenanChina School of life Science Anhui UniversityHefei 230039AnhuiChina

Age and body size a re critical for understanding life history evolution and *** this study,the age and body size of the Shangcheng stout salamander,Pachyhynobius shangchengensis,from a population in Anhui Province,China,were studied by *** mean age was 8.8±0.2(mean±SD)years in females and 9.6±0.2 in males and ranged 5-13 years for both *** mean age was significantly different between *** mean body size and mass were(100.21±0.91)mm and(31.76±0.73)g in females,and(105.31±1.23)mm and(37.14±1.12)g in males,*** were significantly larger and heavier than females,indicating sexual size *** was a significant positive correlation among body size,body mass,and age,suggesting that the oldest individuals are larger and *** growth rate in males was significantly higher than in *** present study provides preliminary data on life-history traits which can be helpful for future studies of this species and other hynobiid salamanders.

关键词： age structure growth rate life history skeletochronology

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Urban expansion and intra-urban land evolution as well as their natural environmental constraints in arid/semiarid regions of China from 2000–2018

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Journal of Geographical Sciences 2023年第7期33卷 1419-1441页

作者： pan tao KUANG Wenhui SHAO Hua ZHANG Chi WANG Xiaoyu WANG Xinqing School of Geography and Tourism Qufu Normal UniversityRizhao 276826ShandongChina Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyCASUrumqi 830011China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources and EnvironmentLinyi UniversityLinyi 276000ShandongChina

Rapid urbanization has occurred in arid/semiarid China,threatening the sustainability of fragile dryland ecosystems;however,our knowledge of natural environmental constraints on multiscale urban lands in this region is still *** solve this issue,this study retrieved 15-m multiscale urban *** indicated that urban area increased by 68%during 2000–2018,and one-third of the increase was contributed by only three large *** coverage of impervious surface area(ISA) and vegetated area(VA) increased by 16.6%and 1.38%,*** land-cover change may be helpful in suppressing wind erosion and sand *** also found that the newly urban lands had relatively lower ISA and higher VA than the old urban lands,indicating an improved human settlement *** environmental constraints on urban expansion were identified,with cities in oasis urban environments(OUEs) that had water supply expanding 150% faster than cities in desert urban environments(DUEs).Urban development was also constrained by terrain,with 73% of the ISA expansion occurring in relatively flat ***,the aggregated pattern of urbanization and the increase in ISA and VA in the newly urbanized lands have improved water-use efficiency and ecological services and benefited desert ecosystem protection in arid/semiarid China.

关键词： urbanization natural environmental constraints pixel and subpixel land change arid and semiarid regions of China

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Equidistant combination wavelength screening and step-by-step phase-out method for the near-infrared spectroscopic analysis of serum urea nitrogen

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Journal of Innovative Optical Health Sciences 2019年第6期12卷 85-96页

作者： Yihui Yang Fenfen Lei Jing Zhang Lijun Yao Jiemei Chen tao pan Department of Optoelectronic Engineering Jinan University Huangpu Road West 601 Tianhe DistrictGuangzhou 510632P.R.China Department of Biological Engineering Jinan University Huangpu Road West 601 Tianhe DistrictGuangzhou 510632P.R.China

We applied near-infrared(NIR)spectroscopy with chemometrics for the rapid and reagent-fee analysis of serum urea nitrogen(SUN).The modeling is based on the average effect of multiple sample partitions to achieve parameter selection with stability.A multiparameter optimization platform with Norris derivative filter-partial least squares(Norris-PLS)was developed to select the most suitable mode(d=2,s=33,g=15).Using equidistant combination PLS(EC-PLS)with four parameters(initial wavelength I,number of wavelengths N,number of wavelength gaps G and latent variables LV),we performed wavelength screening after eliminating high-absorption *** optimal EC-PLS parameters were I=1228 nm,N=26,G=16 and LV=*** root-mean square error(SEP),correlation coefficient(R_(p))for prediction and ratio of performance-to-deviation(RPD)for validation were 1.03 mmol L^(-1),0.992 and 7.6,*** proposed the wavelength step-by-step phase-out PLS(WSP-PLS)to remove redun-dant wavelengths in the top 100 EC-PLS models with improved prediction *** combination of 19 wavelengths was identifed as the optimal model for *** SEP,Rp and RPD in validation were 1.01 mmol L^(-1),0.992 and 7.7,*** prediction effect and wavelength complexity were better than those of *** results showed that NIR spectroscopy combined with the EC-PLS and WSP-PLS methods enabled the high-precision analysis ***-PLS is a secondary optimization method that can further optimize any wavelength moc odel obtained through other continuous or discrete strategies to establish a simple and better model.

关键词： Serum urea nitrogen near infrared spectroscopic analysis Norris derivative filter equidistant combination wavelength screening wavelength step-by-step phase-out

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Systematics and Species Validity of the Dabieshan Pit Viper Protobothrops dabieshanensis Huang et al. 2012: Evidence from a Mitochondrial Gene Sequence Analysis

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Asian Herpetological Research 2013年第4期4卷 282-287页

作者： Baowei ZHANG Xin HUANG tao pan Liang ZHANG Wenliang ZHOU tao SONG Demin HAN School of Life Sciences Anhui University Guangdong Entomological Institute and South China Institute of Endangered Animals

Aimed to evaluate the phylogenetic position of the recently described Protobothrops dabieshanensis Huang et al. （2012）, phylogenic relationships of 12 species within Protobothrops based on four mtDNA gene fragments （12S RNA, 16S RNA, ND4 and Cyt b） were reconstructed in our study. The result indicates a clade composed ofP dabiesha- nensis, P. jerdonii and P xiangchengsis with strong support. The genetic distance among P dabieshanensis, P jerdonii and P xiangchengsis was much lower than other congeners. Based on the data from the phylogenetic analysis and pre- viously described morphological differences, we conclude that P dabieshanensis is a valid species with close affinities to P jerdonii and P xiangchengsis.

关键词： phylogeny Crotalinae systematics venomous snakes

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基于多光谱交互注意力融合的多尺度无人机小目标检测

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四川大学学报（自然科学版） 2024年第3期61卷 136-143页

作者：吴长柯陈虎潘涛黄菊刘洪张萍吴志红苏强四川大学视觉合成图形图像技术重点学科实验室成都610065 61287部队成都610036 四川大学计算机学院成都610065 中国东方电气集团有限公司成都611731 电子科技大学光电科学与工程学院成都611731

针对无人机检测中存在的目标较小、受背景环境影响大、以及多光谱特征难以深度融合等问题,本文提出了针对无人机小目标检测的多尺度多光谱交互注意力融合目标检测模型.首先,将骨干网络设计为双流网络,分别提取不同尺度红外和可见光特征... 详细信息

针对无人机检测中存在的目标较小、受背景环境影响大、以及多光谱特征难以深度融合等问题,本文提出了针对无人机小目标检测的多尺度多光谱交互注意力融合目标检测模型.首先,将骨干网络设计为双流网络,分别提取不同尺度红外和可见光特征,并增加小目标检测层和BiFPN级联操作,提升对无人机小目标特征的提取能力.其次,创新性的设计了多光谱交互注意力融合模块,在该融合模块的指导下,网络可以在不同尺度融合红外和可见光模态的信息,使红外和可见光的特征进行深度聚合,发挥各自模态的优势,指导开展无人机小目标检测.实验结果表明,与最先进的多光谱目标检测模型相比,本文提出的模型在FLIR、LLVIP两个公开的多光谱目标检测数据集上都达到了优越的性能,在构建的多光谱无人机数据集上,本文提出的模型有效提升了无人机的检测精度和鲁棒性.

关键词：无人机检测小目标检测多光谱交互注意力融合多尺度

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面向新工科的混合式教学在医学仪器学中的探索

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电脑与信息技术 2024年第4期32卷 118-121页

作者：董利尚志会潘桃桃谢小芳左均欢遵义医科大学医学信息工程学院贵州遵义563000

为了满足智能医学卓越人才培养目标的要求,适应各级医疗机构所需,需要培养一批具有较强实践能力、自主学习能力和创新思维能力的应用型智能医学高素质人才。基于此,总结了医学信息工程专业“医学仪器学”课程教学实践中发现的问题,包括... 详细信息

为了满足智能医学卓越人才培养目标的要求,适应各级医疗机构所需,需要培养一批具有较强实践能力、自主学习能力和创新思维能力的应用型智能医学高素质人才。基于此,总结了医学信息工程专业“医学仪器学”课程教学实践中发现的问题,包括思政元素不足、授课内容单一、学生岗位胜任力欠缺、学习被动等,提出了以教学问题为导向,开展线上资源与思政内容+理论教学与实践教学+翻转课堂与思维导图融合的混合式教学改革探索。实践结果表明,采用混合式教学方法,课程的教学质量得到了提升,学生的创新能力、实践能力和创新思维能力均有明显改观。

关键词：智能医学混合式教学医学仪器学

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