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Effect of thermal shield and gas flow on thermal elastic stresses in 300mm silicon crystal

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Rare Metals 2006年第z2期25卷 45-50页

作者： gao yu xiao Qinghua ZHOU Qigang DAI xiaolin TU Hailing General Research Institute for Nonferrous Metals Beijing 100088 China General Research Institute for Nonferrous Metals Beijing 100088 China General Research Institute for Nonferrous Metals Beijing 100088 China General Research Institute for Nonferrous Metals Beijing 100088 China General Research Institute for Nonferrous Metals Beijing 100088 China

The thermal elastic stresses induced in 300 mm Si crystal may be great troubles because it can incur the generation of dislocations and undesirable excessive residual stresses. A special thermal modeling tool, CrysVUn, was used for numerical analysis of thermal elastic stresses and stress distribution of 300 mm Si crystal under the consideration of different thermal shields and gas flow conditions. The adopted governing partial equations for stress calculation are Cauchy′s first and second laws of motion. It is demonstrated that the presence and shape of thermal shield, the gas pressure and velocity can strongly affect von Mises stress distribution in Si crystal. With steep-wall shield, however, the maximal stress and ratio of high stress area are relatively low. With slope-wall shield or without shield, both maximal stress and ratio of high stress area are increased in evidence. Whether thermal shields are used or not, the increase of gas flow velocity could raise the stress level. In contrast, the increase of gas pressure cannot result in so significant effect. The influence of thermal shield and gas flow should be attributed to the modification of heat conduction and heat radiation by them.

关键词： thermal elastic stress simulation 300 mm Si single crystal

A Novel Plasticizer for the Preparation of Thermoplastic Starch

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Chinese Chemical Letters 2006年第1期17卷 133-136页

作者： Jin Hui YANG Jiu gao yu xiao Fei MA School of Science Tianjin University Tianjin 300072

in this paper, ethylenebisformamide was synthesized and used as a novel plasticizer for cornstarch to prepare thermoplastic starch （TPS）. FT-IR expressed that ethylenebisformamide formed stronger and stable hydrogen bond with starch molecules compared to the native cornstarch. X-ray diffraction （XRD） showed that the typical A-style crystallinity in the native starch has been destructed. By scanning electron microscope （SEM） native cornstarch granules were proved to transfer to a homogeneous system. After being stored for one week at RH=33%, the mechanical properties of EPTPS was also studied. The elongation reached to 264% utmost. As a novel plasticizer, ethylenebisformamide would be practical to extend TPS application scopes.

关键词： Thermoplastic starch ethylenebisformamide novel plasticizer.

An efficient and facile procedure for synthesis of octyl polyglucoside

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Chinese Chemical Letters 2007年第10期18卷 1173-1175页

作者： Ying Wu Jiu gao yu xiao Fei Ma Jian She Zhang Department of Chemistry School of Science Tianjin University Tianjin 300072 China

Nonionic surfactant alkyl polyglucoside （APG） was prepared by direct glycosidation of alkyl alcohol with glucose in the presence of sulfate acid-silica gel （H2SO4/SiO2） as solid acidic catalyst. The quantity of catalyst was only of 1 wt%, based on the glucose, and the conversion of glucose was close to 100% at 110 ℃ in 1.5 h. The product was characterized by FT-IR, mass and ^1H NMR spectra. The degree of polymerization （DP） of the glucose in the product was 1.37, and critical micelle concentration （CMC） of product was only 0.0104 wt%.

关键词： Alkyl polyglucoside Sulfate acid-silica gel Solid acidic Catalyst

EnKF Assimilation of Satellite-retrieved Cloud Water Path to Improve Tropical Cyclone Rainfall Forecast

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Journal of Tropical Meteorology 2021年第3期27卷 201-217页

作者： gao xiao-yu LIN Yan-luan yuE Jian Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing 100084 China Center of Numerical Weather Predication China Meteorological AdministrationBeijing 100081 China

Tropical cyclone(TC) rainfall forecast has remained a challenge. To create initial conditions with high quality for simulation, the present study implemented a data assimilation scheme based on the EnKF method to ingest the satellite-retrieved cloud water path(C_(w)) and tested it in WRF. The scheme uses the vertical integration of forecasted cloud water content to transform control variables to the observation space, and creates the correlations between C_(w) and control variables in the flow-dependent background error covariance based on all the ensemble members, so that the observed cloud information can affect the background temperature and humidity. For two typhoons in 2018(Yagi and Rumiba), assimilating C_(w) significantly increases the simulated rainfalls and TC intensities. In terms of the average equitable threat score of daily moderate to heavy rainfall(5-120 mm), the improvements are over 130%, and the dry biases are cut by about 30%. Such improvements are traced down to the fact that C_(w) assimilation increases the moisture content, especially that further away from the TC center, which provides more precipitable water for the rainfall,strengthens the TC and broadens the TC size via latent heat release and internal wind field adjustment.

关键词： tropical cyclone data assimilation EnKF cloud water path

Core shift limitation in investment casting process of hollow turbine blade

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Chinese Journal of Aeronautics 2024年第8期37卷 513-526页

作者： Kang CUI Lin JING Ruisong JIANG Longnv yu xiao gao Automation and Software Engineering Shanxi UniversityTaiyuan 030006China Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologySchool of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China School of Mechanical Engineering Sichuan UniversityChengdu 610065China

The deviation in wall thickness caused by core shift during the investment casting process significantly impacts the strength and service life of hollow turbine *** address this issue,a core shift limitation method is developed in this ***,a shift model is established based on computational fluid dynamics and motion simulation to predict the movement of the ceramic core in investment casting ***,utilizing this model,an optimization method for fixturing layout inside the refractory ceramic shell is devised for the ceramic *** casting experiment demonstrates that by utilizing the optimized fixture layout,not only can core shift during the investment casting pouring process be effectively controlled,but also the maximum wall thickness error of the blade can be reduced by 42.02%.In addition,the core shift prediction is also validated,with a prediction error of less than 26.9%.

关键词： Hollow turbine blade Wall thickness Ceramic core Shift prediction Fixturing layout optimization

AECOPD合并Ⅱ型呼吸衰竭患者发生营养风险的影响因素分析及其预测模型构建

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现代生物医学进展 2024年第10期24卷 1883-1887页

作者：刘敏高笑宇杨海丽赵历超李晓玲内蒙古自治区人民医院呼吸与危重症医学科内蒙古呼和浩特010010 内蒙古自治区人民医院临床医学研究中心内蒙古呼和浩特010010

目的:探讨慢性阻塞性肺疾病急性加重期(AECOPD)合并Ⅱ型呼吸衰竭患者发生营养风险的影响因素,并构建预测模型。方法:回顾性选择2021年1月至2022年12月内蒙古自治区人民医院收治的AECOPD合并Ⅱ型呼吸衰竭患者177例,根据营养风险筛查2002(... 详细信息

目的:探讨慢性阻塞性肺疾病急性加重期(AECOPD)合并Ⅱ型呼吸衰竭患者发生营养风险的影响因素,并构建预测模型。方法:回顾性选择2021年1月至2022年12月内蒙古自治区人民医院收治的AECOPD合并Ⅱ型呼吸衰竭患者177例,根据营养风险筛查2002(NRS2002)评分将患者分为营养风险组(122例)和无营养风险组(55例)。单因素和多因素Logistic回归分析AECOPD合并Ⅱ型呼吸衰竭患者营养风险的影响因素,并根据回归模型构建预测模型。受试者工作特征(ROC)曲线验证预测模型的预测效能。结果:单因素分析显示营养风险组年龄大于无营养风险组(P0.05,模型拟合效果良好。结论:高龄、高m MRC评分、合并慢性胃病、高NLR是AECOPD合并Ⅱ型呼吸衰竭患者发生营养风险的危险因素,高FEV_(1)/FVC是保护因素。基于回归模型预测AECOPD合并Ⅱ型呼吸衰竭患者发生营养风险具有较高的价值。

关键词：慢性阻塞性肺疾病急性加重期 Ⅱ型呼吸衰竭营养风险影响因素预测模型

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椰枣多糖缓解功能性便秘的作用研究

食品安全质量检测学报 2024年第9期15卷 313-320页

作者：刘莉郭凯枫唐旭敏赵艳田洋高晓余食药同源资源开发与利用教育部工程研究中心昆明650201 云南省精准营养与个性化食品制造重点实验室昆明650201 云南农业大学食品科学技术学院昆明650201 云南农业大学科技处昆明650201

目的在动物水平探究椰枣多糖的通便活性。方法采用洛哌丁胺诱导的功能性便秘小鼠模型评价椰枣多糖。将小鼠随机分为空白对照组、模型对照组、阳性对照组和低、中、高剂量椰枣多糖组;连续处理7d后,通过排便实验和小肠运动实验来评价椰枣... 详细信息

目的在动物水平探究椰枣多糖的通便活性。方法采用洛哌丁胺诱导的功能性便秘小鼠模型评价椰枣多糖。将小鼠随机分为空白对照组、模型对照组、阳性对照组和低、中、高剂量椰枣多糖组;连续处理7d后,通过排便实验和小肠运动实验来评价椰枣多糖的通便效果;采用实时荧光定量聚合酶链反应(quantitative real-time polymerase chain reaction,qPCR)检测结肠组织中水通道蛋白相关基因的表达。结果排便实验结果表明,椰枣多糖能够显著缩短便秘小鼠首粒排黑便时间,明显增加6 h内的粪便粒数、粪便湿重以及粪便含水率;小肠运动实验结果表明,椰枣多糖显著增加便秘小鼠小肠墨汁推进率,且呈现出一定的剂量依赖性;qPCR结果表明,椰枣多糖显著下调AQP3的基因表达、上调AQP9的基因表达。结论椰枣多糖能够显著改善洛哌丁胺引起的小鼠便秘症状,且通便效果温和、无不良副作用,可能通过调节水通道蛋白基因的表达从而增加便秘小鼠粪便含水量。

关键词：椰枣多糖排便实验小肠运动实验水通道蛋白

Knowledge Graph Enhanced Transformers for Diagnosis Generation of Chinese Medicine

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Chinese Journal of Integrative Medicine 2024年第3期30卷 267-276页

作者： WANG Xin-yu YANG Tao gao xiao-yuan HU Kong-fa School of Artificial Intelligence and Information Technology Nanjing University of Chinese MedicineNanjing210023China School of Information Management Nanjing UniversityNanjing210023China Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine in Prevention and Treatment of Tumor Nanjing210023China Jiangsu Province Engineering Research Center of TCM Intelligence Health Service Nanjing210023China

Chinese medicine(CM)diagnosis intellectualization is one of the hotspots in the research of CM *** traditional CM intelligent diagnosis models transform the CM diagnosis issues into classification issues,however,it is difficult to solve the problems such as excessive or similar *** the development of natural language processing techniques,text generation technique has become increasingly *** this study,we aimed to establish the CM diagnosis generation model by transforming the CM diagnosis issues into text generation *** semantic context characteristic learning capacity was enhanced referring to Bidirectional Long Short-Term Memory(BILSTM)with Transformer as the backbone ***,the CM diagnosis generation model Knowledge Graph Enhanced Transformer(KGET)was established by introducing the knowledge in medical field to enhance the inferential *** KGET model was established based on 566 CM case texts,and was compared with the classic text generation models including Long Short-Term Memory sequence-to-sequence(LSTM-seq2seq),Bidirectional and Auto-Regression Transformer(BART),and Chinese Pre-trained Unbalanced Transformer(CPT),so as to analyze the model ***,the ablation experiments were performed to explore the influence of the optimized part on the KGET *** results of Bilingual Evaluation Understudy(BLEU),Recall-Oriented Understudy for Gisting Evaluation 1(ROUGE1),ROUGE2 and Edit distance of KGET model were 45.85,73.93,54.59 and 7.12,respectively in this *** with LSTM-seq2seq,BART and CPT models,the KGET model was higher in BLEU,ROUGE1 and ROUGE2 by 6.00–17.09,1.65–9.39 and 0.51–17.62,respectively,and lower in Edit distance by 0.47–*** ablation experiment results revealed that introduction of BILSTM model and prior knowledge could significantly increase the model ***,the manual assessment indicated that the CM diagnosis results of the KGET model used

关键词： Chinese medicine diagnosis knowledge graph enhanced transformer text generation

Catch organism assemblages along artificial reefs area and adjacent waters in Haizhou Bay

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Acta Oceanologica Sinica 2024年第2期43卷 34-42页

作者： Shike gao Bin Xie Chengyu Huang xiao Zhang Shuo Zhang Wenwen yu College of Marine Living Resource Sciences and Management Shanghai Ocean UniversityShanghai 201306China Jiangsu Research Institute of Marine Fisheries Nantong 226007China Third Institute of Oceanography Ministry of Natural ResourcesXiamen361005China Joint Laboratory for Monitoring and Conservation of Aquatic Living Resources In the Yangtze Estuary Shanghai 200000China

To better understand the community patterns mediated by connectivity in artificial reefs of coastal areas, it is necessary to understand the distribution and coexistence of organisms with artificial reefs area and adjacent waters. This study was conducted to examine main catches assemblages collected by trawls in Haizhou Bay,which included five habitats: the artificial reef area(AR), aquaculture area(AA), natural area(NA), estuary area(EA) and comprehensive effect area(CEA). The result shows that the total abundances of species in the five habitats were highly different(univariate PERMANOVA: P = 0.001, n = 24), but some species were also unique in their habitat(e.g. Scapharca subcrenata and Glossaulax didyma in AA). The body size distribution of specific species between habitats are different. For Collichthys lucidus, their body size in AR(14.63 cm ± 1.64 cm) and EA(14.3 cm ± 0.85 cm) is higher than that in NA(10.65 cm ± 1.64 cm), CEA(11.28 cm ± 1.85 cm) and AA(12.1 cm ±0.43 cm), which indicates the potential connection from AR to EA mediated by their adult population. We concluded that artificial reefs in AR can be considered key components that have the ability to support species assemblages in adjacent habitats. This study has implications for the conservation and monitoring of species assemblages in coastal areas in terms of that artificial reefs can be applied in different stages of habitat protection implementation and in different combinations of scenarios.

关键词： assemblage artificial reefs adjacent water Haizhou Bay