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化工学报 2005年第1期56卷 16-23页

作者：孙凤侠卢春喜时铭显石油大学(北京)化工学院北京102249

为进一步提高催化裂化沉降器旋流快分系统的分离效率 ,首先对系统内气相流场进行了研究和分析 .采用CFX5软件和应力输运方程模型 (DSM)对其气相流场进行了三维数值模拟 .将计算结果与用五孔探针测试的流场实验结果对比发现 ,计算结果与... 详细信息

为进一步提高催化裂化沉降器旋流快分系统的分离效率 ,首先对系统内气相流场进行了研究和分析 .采用CFX5软件和应力输运方程模型 (DSM)对其气相流场进行了三维数值模拟 .将计算结果与用五孔探针测试的流场实验结果对比发现 ,计算结果与实验结果吻合较好 ,证明了应力输运方程模型适合用于旋流快分系统内三维流场的数值模拟 .模拟结果表明 :旋流快分系统内的流场为三维湍流场 ,在旋流头喷出口附近区域存在多个纵向旋涡 ,存在短路流现象 ,这是导致分离效率不易提高的主要原因 .旋流快分头的S值和倾斜角对气流切向速度都有一定的影响 ,应优化确定 .加入汽提气后 ,对旋流快分系统内的流场影响不大 ,但对气体的快速引出有利 .

关键词：旋流快分器数值模拟流场旋流

催化裂化沉降器新型高效旋流快分器内气固两相流动

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化工学报 2005年第12期56卷 2280-2287页

作者：孙凤侠卢春喜时铭显中国石油化工股份有限公司上海石油化工研究院上海201208 中国石油大学(北京)化工学院北京102249

用CFX软件对催化裂化沉降器新型旋流快分器的气相流场进行了三维模拟,湍流模型采用雷诺应力输运方程模型.计算结果与用五孔探针测试的气相流场实验结果吻合很好.采用离散轨道模型对该旋流快分器内颗粒的运动情况进行了计算,并由此估算... 详细信息

用CFX软件对催化裂化沉降器新型旋流快分器的气相流场进行了三维模拟,湍流模型采用雷诺应力输运方程模型.计算结果与用五孔探针测试的气相流场实验结果吻合很好.采用离散轨道模型对该旋流快分器内颗粒的运动情况进行了计算,并由此估算了旋流快分器的分级效率和总分离效率.模拟结果表明:该新型旋流头可消除现有旋流头喷出口附近的短路流,更有利于提高旋流快分器的效率.两种结构形式的旋流快分器分离效率的计算对比说明:在旋流头处加入一个内构件,是很有价值的改进.

关键词：旋流快分器数值模拟流场分离效率

Synthesis of Amphiphilic Starch Derivatives Using One-pot Synthesis Procedure

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Paper And Biomaterials 2018年第1期3卷 1-9页

作者： Tao Song fengxia Yue XueZhu Xu ChunLin Xu Yi-Chen Li FaChuang lu HaiSong Qi State Key Laboratory of Pulp and Paper Engineering School of Light Industry and EngineeringSouth China University of Technology Department of Biochemistry and DOE Great Lakes Bioenergy Research Center Wisconsin Energy Institute University of Wisconsin–Madison Fiber and Polymer Science University of California Johan Gadolin Process Chemistry Centre Laboratory of Wood and Paper Chemistry Faculty of Science and Engineering ?bo Akademi University Biomaterials Innovation Research Center Department of Medicine Brigham and Women's Hospital Harvard Medical School

Amphiphilic starch derivatives with high content of functional groups were prepared from potato starch using a one-pot synthesis method with a single reaction medium for the entire procedure. Potato starch was benzylated, followed by the introduction of hydroxypropyltrimethylammonium(HPMA) moieties without the purification of intermediates. The synthesis was performed under heterogeneous conditions, leading to the formation of benzyl 2-hydroxypropyltri methylammonium starch chloride(BnHPMAS) with a total degree of substitution(DS) of up to 1.4. This process improved the efficiency of the preparation of amphiphilic starch derivatives and reduced the time and resources consumed by avoiding a separation process and purification of the intermediate *** DS of BnHPMAS was in the range of 0.36 to 1.4, which could be tuned by varying the molar ratio of the reagents to repeating unit or by changing the reaction temperature, time, and medium. The structure of the amphiphilic starches was characterized using elemental analysis, size exclusion chromatography,fourier transform infrared spectroscopy(FT-IR), and nuclear magnetic resonance(NMR) spectroscopy. Moreover, the surface tension and turbidity of the solutions of the products were measured for their potential application in the removal of dissolved and colloidal substances in paper cycling water.

关键词： amphiphilicstarchderivatives chemicalmodification degreeofsubstitution turbidity

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番茄亲本材料耐热特性

东北林业大学学报 2012年第6期40卷 105-107页

作者：苏小霞卢宝伟安凤霞黑龙江省生态工程职业学院哈尔滨150025 黑龙江省科学院自然与生态研究所

对用于耐热性遗传分析的番茄亲本材料进行高温处理,并对处理后的番茄幼苗热害指数、叶片质膜透性、游离脯氨酸质量分数和超氧化物歧化酶活性等各项理化指标进行了测定。结果表明:对6份供试材料进行耐热性分析,所得结论一致,划分的耐热... 详细信息

对用于耐热性遗传分析的番茄亲本材料进行高温处理,并对处理后的番茄幼苗热害指数、叶片质膜透性、游离脯氨酸质量分数和超氧化物歧化酶活性等各项理化指标进行了测定。结果表明:对6份供试材料进行耐热性分析,所得结论一致,划分的耐热型结果无差异。品种CLN2001A、CLN2418A和CLN2366A为R型(耐热),品种01241为S型(较耐热),而01143和01137为T型(不耐热)。

关键词：番茄亲本材料耐热性

Author Correction:A novel recombinant DNA vaccine encoding Mycobacterium tuberculosis ESAT-6 and FL protects against Mycobacterium tuberculosis challenge in mice

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The Journal of Biomedical Research 2022年第6期36卷 448-450页

作者： Qingtao Jiang Jing Zhang Xia Chen Mei Xia Yanlai lu Wen Qiu Ganzhu Feng Dan Zhao Yan Li fengxia He Guangyong Peng Yingwei Wang Department of Microbiology and Immunology Nanjing Medical UniversityNanjingJiangsu 211166China Division of Infectious Diseases Allergy and ImmunologyDepartment of Internal MedicineSaint Louis University School of MedicineSt.LouisMissouri 63104USA

Correction to:Journal of Biomedical Research https://***/10.7555/JBR.27.20120114,published on 30 September *** apologize for the misused images in Fig.7 in our article published on 30 September *** Fig.7 by HE staining and immunohistochemistry were partially misused because of our *** we couldn't find the original pictures acquired 11 years ago,thus HE and IHC experiments were repeated by our previously reserved wax ***,the pictures taken by microscope imaging system in each group were collected and combined,*** correct version of Fig.

关键词： tuberculosis immunohistochemistry picture

维普期刊数据库评论

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甘南地区黄芩抗旱栽培模式

东北林业大学学报 2013年第7期41卷 69-70,107页

作者：苏小霞安凤霞卢宝伟黑龙江生态工程职业学院哈尔滨150025 黑龙江省科学院自然与生态研究所

从甘南地区近几年连续发生春旱,给农业生产增收带来严重影响这一实际情况出发,对灌后覆膜和垄作栽培前后黄芩土壤含水量,及相应的黄芩生物量变化情况进行了比较分析。结果表明:灌后覆膜技术的保墒效果要优于垄作栽培技术,提高了黄芩的... 详细信息

从甘南地区近几年连续发生春旱,给农业生产增收带来严重影响这一实际情况出发,对灌后覆膜和垄作栽培前后黄芩土壤含水量,及相应的黄芩生物量变化情况进行了比较分析。结果表明:灌后覆膜技术的保墒效果要优于垄作栽培技术,提高了黄芩的抗旱能力。灌后覆膜栽培技术能有效的提高黄芩的产量,每公顷纯收入增加500～900元。

关键词：甘南黄芩抗旱栽培模式

Expression and purification of recombinant human hemangiopoietin in Escherichia coli

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Journal of Medical Colleges of PLA(China) 2008年第3期23卷 148-153页

作者： Ren Qian Ma fengxia Chen Zhong lu Shihong Han Zhibo Liu Yongjun Xu Bin Zhang Xiangyu Han Zhongchao State Key Laboratory of Experimental Hematology National Research Center for Stem CellEngineering and Technology Institute of Hematology Hospital of Blood Diseases Chinese Academy of Medical Sciences Peking Union of Medical College Tianjin 300020 China

Objective:To express the soluble recombinant hemangiopoietin protein in *** BL21(DE3).Methods:Using human fetal live cDNA as a template,a partial cDNA fragment of HAPO coding N-terminal region was subcloned into plasmids pTrc99,pQE60 and pET32c to construct different recombinant prokaryotic expression *** selecting,the soluble rhHAPO fusion protein was expressed stably in *** BL21(DE3) by vector pET32c-HAPO and further isolated by nickelnitrilotriacetic acid(NTA) affinity *** cleavage with enterokinase,the rhHAPO protein was applied to Fast Flow SP sepharose ***:The rhHAPO protein had a purity of more than 95% and a good bioactivity based on the cell adhesion assay in ECV304 ***:We have established a protein engineering system to produce rhHAPO which may provide the possibility for clinical application.

关键词： Enterokinase Escherichia coli Fusion protein Hemangiopoietin Purification Recombinant protein expression

Multidimensional attention and multiscale upsampling for semantic segmentation

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Journal of Measurement Science and Instrumentation 2022年第1期13卷 68-78页

作者： lu Zhongda ZHANG Chunda WANG Lijing XU fengxia School of Mechanical and Electrical Engineering Qiqihar University Qiqihar 161000 China Heilongjiang Province Collaborative Innovation Center for Intelligent Manufacturing Equipment Industrialization Qiqihar 161000 China

Semantic segmentation is for pixel-level classification tasks,and contextual information has an important impact on the performance of *** order to capture richer contextual information,we adopt ResNet as the backbone network and designs an encoder-decoder architecture based on multidimensional attention(MDA)module and multiscale upsampling(MSU)*** MDA module calculates the attention matrices of the three dimensions to capture the dependency of each position,and adaptively captures the image *** MSU module adopts parallel branches to capture the multiscale features of the images,and multiscale feature aggregation can enhance contextual information.A series of experiments demonstrate the validity of the model on Cityscapes and Camvid datasets.

关键词： semantic segmentation attention mechanism multiscale feature convolutional neural network(CNN) residual network(ResNet)

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自适应重复控制抑制测试台动不平衡扰动研究

机械工程学报 2010年第2期46卷 172-177页

作者：徐凤霞赵学增陆仲达齐齐哈尔大学计算机与控制工程学院齐齐哈尔161006 哈尔滨工业大学机电学院哈尔滨150001

通过分析三轴测试台的动不平衡因素,得出测试台存在周期扰动力矩。该周期扰动力矩主要是由加速度力矩、哥氏耦合力矩、离心耦合力矩组成,与测试台三轴的转动惯量、位置角和转动速度有关,影响测试台的定位精度和速率精度。为抑制三轴测... 详细信息

通过分析三轴测试台的动不平衡因素,得出测试台存在周期扰动力矩。该周期扰动力矩主要是由加速度力矩、哥氏耦合力矩、离心耦合力矩组成,与测试台三轴的转动惯量、位置角和转动速度有关,影响测试台的定位精度和速率精度。为抑制三轴测试台动不平衡引起的不确定性频率周期性扰动力矩,提出一种用于消除带有的周期性扰动的自适应有限维重复控制。采用自适应算法在线辨识扰动频率,并调整有限维重复控制器参数消除该扰动,用平均方法证明算法的收敛性和系统的稳定性。同时该算法可以通过调整自适应多周期有限维重复控制器的结构来消除不同频率的多个周期的扰动。仿真结果表明该方法能有效的抑制三轴测试台动不平衡引起的周期性扰动,提高测试台系统的定置精度和速率精度。

关键词：三轴测试台动不平衡周期性扰动自适应算法有限维重复控制