The formation cause of orange peel of aluminum-alloy automotive sheet after tensile deformation was analysed by using X-ray diffraction and electron back-scattered diffraction(EBSD).The test results showed that format...The formation cause of orange peel of aluminum-alloy automotive sheet after tensile deformation was analysed by using X-ray diffraction and electron back-scattered diffraction(EBSD).The test results showed that formation cause of surface orange peel after tensile deformation related to product texture and nonuniform deformation during the tensile process.The grain size has significant effect on deformation uniform and texture formation.Coarse grains were easy to produce nonuniform deformation and texture,which would produce surface orange peel after tensile deformation.展开更多
Using high strength steel and ultra-high strength steel in hot stamping and automobile parts is one of the most important ways of the automobile lightweight,which is the development trend of automobiles currently.In t...Using high strength steel and ultra-high strength steel in hot stamping and automobile parts is one of the most important ways of the automobile lightweight,which is the development trend of automobiles currently.In this paper, the development of test device for heat friction coefficient by high strength steel can provide important technical parameters for hot stamping process,making the right selection of equipment types,mold design,technology optimization,and research and development of lubrication medium of press forming.At the same time,the experiments indicate that the instrument has not only accurate test result but also good repeatability.展开更多
目的分析慢性鼻窦炎伴鼻息肉(chronic rhinosinusitis with nasal polyps,CRSwNP)患者嗅觉障碍的影响因素。方法回顾性分析2014—2018年就诊于北京安贞医院行内镜鼻窦手术治疗的CRSwNP患者88例,男性22例,女性66例,年龄(48.1±11.3)...目的分析慢性鼻窦炎伴鼻息肉(chronic rhinosinusitis with nasal polyps,CRSwNP)患者嗅觉障碍的影响因素。方法回顾性分析2014—2018年就诊于北京安贞医院行内镜鼻窦手术治疗的CRSwNP患者88例,男性22例,女性66例,年龄(48.1±11.3)岁(±s,下同)。所有入选患者均于术前行Sniffin′Sticks嗅觉测试、Lund-Mackay评分及改良鼻窦CT嗅区评分、鼻阻力及声反射检查、血常规及血生化等实验室检测、血清特异性IgE检测;术中取鼻息肉组织进行嗜酸粒细胞计数。根据Sniffin′Sticks嗅觉测试结果将患者分成嗅觉功能正常组和嗅觉功能障碍组,两组之间进行临床基线资料比较,根据单因素分析结果,结合临床有意义的指标进一步行多因素Logistic回归模型分析,并初步建立CRSwNP嗅觉障碍的预测模型。设P<0.05为差异有统计学意义。结果88例CRSwNP患者中,嗅觉正常32例(36.4%),嗅觉障碍56例(63.6%),其中嗅觉下降40例(45.5%)、失嗅16例(18.2%)。单因素分析发现,两组间组织嗜酸粒细胞数、血嗜酸粒细胞百分比、血尿素的差异存在统计学意义[12.7[2.0,52.3]个/高倍视野(M[P25,P75],下同)比38.6[16.2,87.0]个/高倍视野、2.75[1.60,4.80]%比4.35[2.50,6.60]%、(5.56±1.15)mmol/L比(4.98±1.33)mmol/L,P值均<0.05];改良鼻窦CT嗅区评分、除窦口鼻道复合体评分外的Lund-Mackay评分的差异均存在统计学意义(P值均<0.05)。多因素Logistic回归模型分析发现,改良鼻窦CT双侧嗅区总分和血尿素的差异具有统计学意义,其中双侧嗅区总分是嗅觉功能的危险因素(OR=2.108,95%CI:1.407~3.159,P<0.001);一定浓度的血尿素是嗅觉功能的保护因素(OR=0.461,95%CI:0.240~0.884,P=0.020)。进一步研究发现,由组织嗜酸粒细胞计数、血嗜酸粒细胞百分比、改良鼻窦CT双侧嗅区总分、总吸气、血尿素组成的预测模型受试者工作特征(ROC)曲线下面积(AUC)的值为0.888(P<0.01),对CRSwNP嗅觉障碍预测效果较好。结论改良鼻窦CT嗅区评分与CRSwNP患者的嗅觉障碍密切相关,一定程度的血尿素升高可能对CRSwNP患者的嗅觉功能有保护作用。展开更多
文摘The formation cause of orange peel of aluminum-alloy automotive sheet after tensile deformation was analysed by using X-ray diffraction and electron back-scattered diffraction(EBSD).The test results showed that formation cause of surface orange peel after tensile deformation related to product texture and nonuniform deformation during the tensile process.The grain size has significant effect on deformation uniform and texture formation.Coarse grains were easy to produce nonuniform deformation and texture,which would produce surface orange peel after tensile deformation.
基金National Science and Technology Supporting Program of China(No.2011BAG03B02)
文摘Using high strength steel and ultra-high strength steel in hot stamping and automobile parts is one of the most important ways of the automobile lightweight,which is the development trend of automobiles currently.In this paper, the development of test device for heat friction coefficient by high strength steel can provide important technical parameters for hot stamping process,making the right selection of equipment types,mold design,technology optimization,and research and development of lubrication medium of press forming.At the same time,the experiments indicate that the instrument has not only accurate test result but also good repeatability.
文摘目的分析慢性鼻窦炎伴鼻息肉(chronic rhinosinusitis with nasal polyps,CRSwNP)患者嗅觉障碍的影响因素。方法回顾性分析2014—2018年就诊于北京安贞医院行内镜鼻窦手术治疗的CRSwNP患者88例,男性22例,女性66例,年龄(48.1±11.3)岁(±s,下同)。所有入选患者均于术前行Sniffin′Sticks嗅觉测试、Lund-Mackay评分及改良鼻窦CT嗅区评分、鼻阻力及声反射检查、血常规及血生化等实验室检测、血清特异性IgE检测;术中取鼻息肉组织进行嗜酸粒细胞计数。根据Sniffin′Sticks嗅觉测试结果将患者分成嗅觉功能正常组和嗅觉功能障碍组,两组之间进行临床基线资料比较,根据单因素分析结果,结合临床有意义的指标进一步行多因素Logistic回归模型分析,并初步建立CRSwNP嗅觉障碍的预测模型。设P<0.05为差异有统计学意义。结果88例CRSwNP患者中,嗅觉正常32例(36.4%),嗅觉障碍56例(63.6%),其中嗅觉下降40例(45.5%)、失嗅16例(18.2%)。单因素分析发现,两组间组织嗜酸粒细胞数、血嗜酸粒细胞百分比、血尿素的差异存在统计学意义[12.7[2.0,52.3]个/高倍视野(M[P25,P75],下同)比38.6[16.2,87.0]个/高倍视野、2.75[1.60,4.80]%比4.35[2.50,6.60]%、(5.56±1.15)mmol/L比(4.98±1.33)mmol/L,P值均<0.05];改良鼻窦CT嗅区评分、除窦口鼻道复合体评分外的Lund-Mackay评分的差异均存在统计学意义(P值均<0.05)。多因素Logistic回归模型分析发现,改良鼻窦CT双侧嗅区总分和血尿素的差异具有统计学意义,其中双侧嗅区总分是嗅觉功能的危险因素(OR=2.108,95%CI:1.407~3.159,P<0.001);一定浓度的血尿素是嗅觉功能的保护因素(OR=0.461,95%CI:0.240~0.884,P=0.020)。进一步研究发现,由组织嗜酸粒细胞计数、血嗜酸粒细胞百分比、改良鼻窦CT双侧嗅区总分、总吸气、血尿素组成的预测模型受试者工作特征(ROC)曲线下面积(AUC)的值为0.888(P<0.01),对CRSwNP嗅觉障碍预测效果较好。结论改良鼻窦CT嗅区评分与CRSwNP患者的嗅觉障碍密切相关,一定程度的血尿素升高可能对CRSwNP患者的嗅觉功能有保护作用。
文摘目的分析嗅觉障碍患者脑白质的完整性。方法收集2014—2016年就诊于首都医科大学附属北京安贞医院耳鼻咽喉头颈外科的21例嗅觉障碍患者(患者组)与16例年龄、性别、受教育程度相匹配的健康志愿者(对照组),对其进行Sniffin′ Sticks嗅觉功能测试及脑磁共振弥散张量成像(diffusion tensor imaging,DTI)检查。以DTI-studio软件处理脑DTI图像,得到各向异性分数(fractional anisotropy,FA)参数图,选择双侧梨状皮层、眶额皮层、海马、岛叶邻近脑白质和内囊为嗅觉相关感兴趣区(region of interest associated with olfactory,ROIawo),计算每个ROIawo的FA值。采用独立样本t检验比较患者组和对照组间ROIawo的FA值差异。结果患者组右侧梨状皮层和右侧眶额皮层下脑白质的FA值均显著低于对照组[0.42±0.05(±s,下同)比0.45±0.05,0.43±0.06比0.49±0.07,t值分别为2.32、2.79,P值均〈0.05]。左侧梨状皮层、左侧眶额皮层下的脑白质FA值与对照组之间的差异无统计学意义(0.43±0.05比0.45±0.04,0.44±0.04比0.47±0.06,t值分别为1.65、1.37,P值均〉0.05)。左右两侧海马、岛叶下方脑白质FA值与对照组之间的差异均无统计学意义(0.45±0.08比0.44±0.08,0.45±0.09比0.44±0.10,0.41±0.08比0.39±0.07,0.41±0.07比0.38±0.05,t值分别为0.30、0.15、0.88、1.34,P值均〉0.05)。左右两侧内囊FA值与对照组之间的差异亦无统计学意义(0.64±0.08比0.63±0.08,0.64±0.07比0.63±0.07,t值分别为0.14、0.35,P值均〉0.05)。结论嗅觉障碍患者的初级、次级嗅觉皮层邻近脑白质可能存在结构连接障碍,ROIawo脑白质完整性的降低,可能是导致嗅觉障碍的发病机制之一。