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International Journal of Minerals,Metallurgy and Materials 2013年第3期20卷 259-265页

作者： Dong Peng Jun Shen qin Tang Cui-ping Wu Yan-bing Zhou College of Material Science & Engineering Chongqing University Fabrication Workshop Dongfang Turbine Co. Ltd.

Aging treatment and various heat input conditions and mechanical properties of TIG welded 606I-T6 alloy joints were adopted to investigate the microstructural evolution by microstructural observations, microhardness tests, and tensile tests. With an increase in heat input, the width of the heat-affected zone （HAZ） increases and grains in the fusion zone （FZ） coarsen. Moreover, the hardness of the HAZ decreases, whereas that of the FZ decreases initially and then increases with an increase in heat input. Low heat input results in the low ultimate tensile strength of the welded joints due to the presence of partial penetrations and pores in the welded joints. After a simple artificial aging treatment at 175℃ for 8 h, the microstructure of the welded joints changes slightly. The mechanical properties of the welded joints enhance significantly after the aging process as few precipitates distribute in the welded seam.

关键词： aluminum alloys tungsten inert gas welding heat input aging mechanical properties microstructure

Reversible Data Hiding in Encrypted Images Based on Adaptive Prediction and Labeling

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Computers, Materials & Continua 2022年第11期73卷 3613-3628页

作者： Jiaohua qin Zhibin He Xuyu Xiang Neal N.Xiong College of Computer Science and Information Technology Central South University of Forestry&TechnologyChangsha410004China Department of Mathematics and Computer Science Northeastern State UniversityTahlequah74464OKUSA

Recently,reversible data hiding in encrypted images(RDHEI)based on pixel prediction has been a hot ***,existing schemes still employ a pixel predictor that ignores pixel changes in the diagonal direction during prediction,and the pixel labeling scheme is *** solve these problems,this paper proposes reversible data hiding in encrypted images based on adaptive prediction and ***,we design an adaptive gradient prediction(AGP),which uses eight adjacent pixels and combines four scanning methods(i.e.,horizontal,vertical,diagonal,and diagonal)for *** can adaptively adjust the weight of the linear prediction model according to the weight of the edge attribute of the pixel,which improves the prediction ability of the predictor for complex *** the same time,we adopt an adaptive huffman coding labeling scheme,which can adaptively generate huffman codes for labeling according to different images,effectively improving the scheme’s embedding performance on the *** experimental results show that the algorithm has a higher embedding *** embedding rate on the test image Jetplane is 4.2102 bpp,and the average embedding rate on the image dataset Bossbase is 3.8625 bpp.

关键词： Reversible data hiding adaptive gradient prediction huffman coding embedding capacity

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聚乙烯塑料的生物降解研究

环境科学 2007年第5期28卷 1165-1168页

作者：杨军宋怡玲秦小燕北京航空航天大学环境工程系北京100083 北京航空航天大学生物工程系北京100083

塑料废弃物是目前最严重的固体废物污染问题,它正以每年4 000万t的速度在环境中积累,而塑料在自然界几乎完全不能被生物降解和参加物质循环,所以从不同方式提高其生物降解效率一直是重要的研究方向.本文从聚乙烯塑料的改性及降解预处理... 详细信息

塑料废弃物是目前最严重的固体废物污染问题,它正以每年4 000万t的速度在环境中积累,而塑料在自然界几乎完全不能被生物降解和参加物质循环,所以从不同方式提高其生物降解效率一直是重要的研究方向.本文从聚乙烯塑料的改性及降解预处理、生物降解途径、主要降解微生物及其酶,以及聚乙烯降解后的物理、化学与生物学性质的变化等方面总结了近年来聚乙烯生物降解的研究进展.提出了开拓聚乙烯降解的生物研究种类,分离并克隆能产生活性基团的关键酶及其基因,以及加强无添加剂的聚乙烯降解研究等方面的研究方向.

关键词：聚乙烯塑料生物降解

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平行圆盘间电流变液的挤压流研究

功能材料 2006年第5期37卷 690-692,696页

作者：杨士普任玲朱克勤清华大学航天航空学院北京100084

采用双粘度本构模型研究了两平行圆盘间电流变液的挤压流特性,壁面边界上采用Navier滑移模型。流场根据其特性被分为两个区域:对称轴附近的牛顿区以及远离对称轴的双粘区;双粘区存在屈服面。本文在牛顿区和双粘区分别求解出其速度场和... 详细信息

采用双粘度本构模型研究了两平行圆盘间电流变液的挤压流特性,壁面边界上采用Navier滑移模型。流场根据其特性被分为两个区域:对称轴附近的牛顿区以及远离对称轴的双粘区;双粘区存在屈服面。本文在牛顿区和双粘区分别求解出其速度场和压力梯度场。壁面上的滑移速度与当地的压力梯度成正比;而压力梯度在牛顿区与r成正比,在双粘区r值较大的地方与r近似成线性关系。通过将压力梯度在双粘区近似为r的线性函数,可积分出流场的压力分布与作用在圆盘上的挤压力。此外,本文还通过计算,考察了速度场的分布特点,分析了滑移系数对速度场、压力梯度场、屈服面位置以及挤压力的影响。

关键词：电流变液挤压流屈服面宾汉模型 Navier滑移条件

3,5-二羧基苯基重氮氨基偶氮苯分光光度法测定微量镍

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冶金分析 2006年第3期26卷 59-61页

作者：王君玲孟双明冯锋郭永刘永文樊月琴山西大同大学化学与生命科学学院山西大同037009 山西大同大学化学与生命科学学院

合成了新三氮烯类显色剂3,5-二羧基苯基重氮氨基偶氮苯(DBDAA)。在TritonX-100存在下的碱性介质中,该试剂与Ni(形成一种稳定的红色络合物,最大吸收波长为530 nm;表观摩尔吸光系数为2.1×***-1;25 mL溶液中,镍质量在0~12μg内符合比尔定... 详细信息

合成了新三氮烯类显色剂3,5-二羧基苯基重氮氨基偶氮苯(DBDAA)。在TritonX-100存在下的碱性介质中,该试剂与Ni(形成一种稳定的红色络合物,最大吸收波长为530 nm;表观摩尔吸光系数为2.1×***-1;25 mL溶液中,镍质量在0~12μg内符合比尔定律。方法用于铝合金中镍的测定,相对标准偏差小于5%,与原子吸收光谱法比较,结果相符。

关键词：合成 3,5-二羧基苯基重氮氨基偶氮苯镍显色反应

Study on the Microstructure of Human Articular Cartilage/Bone Interface

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Journal of Bionic Engineering 2011年第3期8卷 251-262页

作者： Yaxiong Liu qin Lian Jiankang He Jinna Zhao Zhongmin Jin Dichen Li State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Xi'an 710049 P. R. China Institute of Medical and Biological Engineering Leeds' University LS2 9JT UK

For improving the theory of gradient microstructure of cartilage/bone interface, human distal femurs were studied. Scanning Electron Microscope （SEM）, histological sections and MicroCT were used to observe, measure and model the micro- structure of cartilage/bone interface. The results showed that the cartilage/bone interface is in a hierarchical structure which is composed of four different tissue layers. The interlocking of hyaline cartilage and calcified cartilage and that of calcified car- tilage and subchondral bone are in the manner of＂protrusion-pore＂ with average diameter of 17.0 gm and 34.1 lam respectively. In addition, the cancellous bone under the cartilage is also formed by four layer hierarchical structure, and the adjacent layers are connected by bone trabecula in the shape of H, I and Y, forming a complex interwoven network structure. Finally, the simplified structure model of the cartilage/bone interface was proposed according to the natural articular cartilage/bone interface. The simplified model is a 4-layer gradient biomimetic structure, which corresponds to four different tissues of natural cartilage/bone interface. The results of this work would be beneficial to the design of bionic scaffold for the tissue engineering of articular cartilage/bone.

关键词： tissue engineering knee joint articular cartilage/bone interface of cartilage/bone

电阻抗断层扫描指导急性呼吸窘迫综合征机械通气

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中华医学杂志 2024年第15期104卷 1247-1252页

作者：孙骎刘玲杨毅东南大学附属中大医院重症医学科江苏省重症医学重点实验室南京210009

急性呼吸窘迫综合征(ARDS)是临床常见的急危重症,以弥漫性肺间质、肺泡损伤和肺血管通透性增加为特征。CT可用于对ARDS影像学特征、严重程度的评估和预测,但需要转运患者到CT室且仅为静态检查。电阻抗断层扫描(EIT)是近年来在临床应用... 详细信息

急性呼吸窘迫综合征(ARDS)是临床常见的急危重症,以弥漫性肺间质、肺泡损伤和肺血管通透性增加为特征。CT可用于对ARDS影像学特征、严重程度的评估和预测,但需要转运患者到CT室且仅为静态检查。电阻抗断层扫描(EIT)是近年来在临床应用日益广泛的监测工具,可实现床边连续实时肺通气分布的评估,在优化危重病患者的机械通气参数方面有较高的临床价值。本文介绍EIT基本原理及如何更好地使用EIT技术指导ARDS患者的机械通气治疗。

关键词：呼吸窘迫综合征,成人电阻抗断层扫描机械通气

Computer simulation studies of the influence of side alkyl chain on glass transition behavior of carbazole trimer

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Science China Chemistry 2017年第3期60卷 377-384页

作者： Chunyang Yu Li Ma Wei Huang Yongfeng Zhou Jingui qin Deyue Yan State Key Laboratory of Metal Matrix Composites School of Chemistry & Chemical EngineeringShanghai Jiao Tong University Department of Chemistry Wuhan University

In this work,all-atom molecular dynamics simulations were employed to study the influence of the side alkyl chain on glass transition behavior of several carbazole trimers(CT) in a temperature range from 423 to 183 *** glass transition temperatures were obtained from the break in the slope of the volume-temperature curves and found to agree with the experimental *** short time dynamics of four CT molecules were probed by usingvelocity autocorrelation functions and mean-square *** current studies showed that the dynamics of CT systems can be easily interpreted through the cage ***,the investigation of the torsional autocorrelation function and P_(2-state)/P_(3-state) functions showed that the rotational barriers of side chains can slow down the conformational relaxation and lead to stronger temperature dependence of conformational *** relaxation time,characteristic time of P_(2-state)(t) and P_(3-state)(t) functions were all found to have Arrhenius-type temperature dependence.

关键词： carbazole trimer molecular dynamics simulation glass transition relaxation time

Study of a ceramic burner for shaftless stoves

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International Journal of Minerals,Metallurgy and Materials 2009年第2期16卷 149-153页

作者： Fang-qin Dai Su-yi Huang Shao-hua Li Ke Liu School of Energy ＆ Power Engineering Huazhong University of Science and Technology Wuhan 430074 China Thermal Engineering Research Institute Wuhan Research Institute of Metallurgical Construction Wuhan 430081 China

A multi-burner-port annular flameless ceramic burner （MAFCB） of the shaftless stove for blast furnaces was designed. The characteristics of pressure drop, homogeneousness of the flows at burner ports, and distribution of the flows in the chambers and joint were studied by cold model experiments. This type of ceramic burner was successfully applied in 6# blast furnace at Liuzhou Iron ＆ Steel Co. Ltd. （LISC） and this practice proved that it could be used in the hot blast stove and other stoves with a higher efficiency and a higher steadiness of hot blast temperature at 1200℃. With the combustion of blast furnace gas alone, the thermal efficiency was up to 78.95%, saving energy remarkably.

关键词： ceramic burner blast furnace cold model experiments ironmaking

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肤阴洁复方黄松洗液的GC-MS分析

中成药 2005年第9期27卷 1021-1023页

作者：覃洁萍冯旭杨玲芳广西中医学院广西南宁530001

目的采用GCMS法分析肤阴洁复方黄松洗液(黄松、岗柏、满山香等)的成分。方法采用HP5MS弹性石英毛细管柱,程序升温,以EI离子源和四极杆质量分析器进行分析,质谱图用NIST98谱库检索,结合人工谱图解析,鉴定各种成分,并用色谱峰面积归一化... 详细信息

目的采用GCMS法分析肤阴洁复方黄松洗液(黄松、岗柏、满山香等)的成分。方法采用HP5MS弹性石英毛细管柱,程序升温,以EI离子源和四极杆质量分析器进行分析,质谱图用NIST98谱库检索,结合人工谱图解析,鉴定各种成分,并用色谱峰面积归一化法测定其相对百分含量。结果分离出39个色谱峰,鉴定出31种成分,占已分离组分总含量的90以上。其中4松油醇、α石竹烯、β石竹烯、芳樟醇和桉油精是其中所含的相对含量较高的成分。结论该法简便、快速、灵敏度高。

关键词：气相色谱-质谱肤阴洁复方黄松洗液成分分析