基于神经网络系统的附着系数计算模型     

李松龄  裴玉龙  雷同飞 《东北林业大学学报》2008,36(2):56-57,79

对几种附着系数计算模型进行了深入研究,在全面分析了主要影响附着系数因素的基础上,采用神经网络优化算法,分别建立了以路面状况、胎压及车速为输入,以附着系数为输出的3种轮胎花纹的神经网络附着系数计算模型,并验证了模型的有效性。该模型能够计算汽车在不同的行驶工况下的轮胎/路面间的附着系数,从而为附着系数实时监控提供理论依据,为行车安全提供保障。  相似文献   

黏红酵母对牙鲆肠黏液黏附及肠道定植规律的研究     

李正  李健  刘淇  王群 《安徽农业科学》2008,36(17):7271-7272

[目的]研究黏红酵母(Rhodotorula glutinis)、鼠李糖乳杆菌(Lactobacillus rhamnosus)、纳豆芽孢杆菌(Bacillus natto)、嗜酸乳杆菌(Lactobacillus casei)对牙鲆肠黏液的黏附能力,探讨黏红酵母在牙鲆肠道中的定植规律及对牙鲆抗病能力的影响。[方法]采用体外黏液黏附模型测定上述4株益生菌的黏液黏附能力,平板菌落计数法测定黏红酵母在肠道的数量。[结果]黏红酵母对牙鲆肠黏液黏附能力最强,其次是鼠李糖乳杆菌,纳豆芽孢杆菌黏附能力最弱。投喂含黏红酵母饲料的牙鲆肠道其酵母数量达到了103～104cfu/g内含物。鳗弧菌攻毒后,对照组牙鲆死亡率显著高于黏红酵母组。[结论]黏红酵母在牙鲆肠道具有较好定植潜能并能降低牙鲆因弧菌引起的死亡率,因此具有较好的应用前景。  相似文献   

芦苇的表面改性及粘接性能研究   总被引：3，自引：0，他引：3  

赫秀娟  封禄田  李旭日  郝付泼  王书鸣 《林产工业》2008,35(2):27-28

研究以芦苇为原料,以环保的水溶性树脂胶为黏合剂,对芦苇不进行粉碎,而直接粘接用来制造芦苇板,以充分利用其本身强度.用热NaOH溶液对芦苇进行处理,用扫描电子显微镜观察了芦苇表面形貌的变化.结果表明:热NaOH溶液可以破坏芦苇表面的蜡质层,增加其胶接强度;将水溶性酚醛树脂胶黏剂与水溶性聚乙烯醇缩醛胶黏剂配合使用,或加入0.5%的表面活性剂,也可改善其与芦苇的粘接性能.  相似文献   

麦秸人造板表面涂饰试验     

张立芳  吴伟娟 《林业科技开发》2005,19(5):49-50

对麦秸人造板表面分别试验了酚醛树脂、醇酸树脂、聚酯树脂、聚氨酯、聚醋酸乙烯酯腻子，涂刮腻子后再喷涂丙烯酸漆，并测定漆膜附着力。结果表明，聚氨酯腻子漆膜附着力最好，达到了一级质量标准，完全可以满足麦秸板表面涂饰的要求；酚醛树脂腻子与麦秸板粘合效果最差。  相似文献   

AHV-PI attenuates endothelial cell injury induced by LPS     

JI Na  ZHONG Shu-zhi  ZHANG Gen-bao 《园艺学报》2018,34(9):1558-1564

AIM:To investigate the effect of platelet inhibitor from Agkistrodon halys venom (AHV-PI) on lipopolysaccharide (LPS) induced human umbilical vein endothelial cells (HUVECs) injury in vitro, and to explore its mechanism. METHODS:Cultured HUVECs were induced inflammatory injury by LPS (1 mg/L). The experiment was divided into blank control group, LPS group, AHV-PI group and AHV-PI+LPS group. The viability of HUVECs was measured by MTT assay. The morphological changes of HUVECs were observed under inverted microscope. The optimum concentration of AHV-PI at 5 mg/L was selected. Flow cytometry was used to detect apoptosis of HUVECs. Immunohistochemical method was used to observe the expression of tissue type plasminogen activator (t-PA) and plasminogen activator indhibitor-1 (PAI-1) of HUVECs. ELISA was used to detect the concentrations of intercellular adhesion molecule-1 (ICAM-1) and tissue factor (TF) in the supernatant. The activation and translocation of NF-κB subunit p65 were observed by immunofluorescence staining. RESULTS:The HUVECs were spindle shaped, the ratio of length to width was increased, the cells were fibroblast-like, and granular substance appeared in the cytoplasm in LPS group. The viability and morphological changes of HUVECs were not significantly affected as treated with AHV-PI at concentration of 0~5 mg/L, but the viability of HUVECs induced by LPS was inhibited and the morphological changes were alleviated. Compared with the blank control group, the levels of TF and ICAM-1 in the supernatant increased, and the expression of t-PA and PAI-1 in the HUVECs was decreased in LPS group. Compared with the LPS group, the contents of TF and ICAM-1 in the supernatant were significantly decreased, the expression of t-PA and PAI-1 in the HUVECs was increased and the expression of nucleus NF-κB p65 was decreased in AHV-PI+LPS group (P<0.05). CONCLUSION:AHV-PI reduces HUVECs damage. The protective mechanism is related to the inhibition of cytokine secretion and NF-κB activation.  相似文献   

Are There Shared Mechanisms in the Pathophysiology of Different Clinical Forms of Laminitis and What Are the Implications for Prevention and Treatment?     

《Veterinary Clinics of North America: Equine Practice》2019,35(2):379-398

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基于聚乙烯木塑复合材的水披覆转印法装饰     

韦双颖  蔡莹莹  杨黎  张宇  余华  李松林  王亚宁 《东北林业大学学报》2017,45(8)

为提高水披覆转印法装饰的聚乙烯(PE)木塑复合材表面装饰效果和附着力,从分析水披覆转印膜正反面的接触角、润湿速率入手,结合等离子体处理手段,探究了处理时间、表面张力、附着力等因素对转印效果的影响,得出基于PE木塑复合材的水披覆转印法装饰最佳工艺过程及参数。结果表明:正面润湿速率较小而反面润湿速率较大的转印膜转印效果较佳;等离子体处理时间为15 min最佳,PE木塑基材表面和底漆面的表面张力分别提高至48、46 mN·m~(-1),木塑表面的漆膜附着力可达0级;经转印膜装饰后的PE木塑表面带有实木纹理,色泽饱满,明显改善了装饰性和实用性。  相似文献   

产志贺毒素样大肠杆菌F18ab菌毛操纵子基因的体外非诱导系统的表达和鉴定     

吴娟  朱春红  郁磊  羊扬  朱军  舒燕  包文斌  吴圣龙  Dieter M Schifferli  朱国强 《兽医大学学报》2012,(10):1444-1447,1477

以产志贺毒素样大肠杆菌（SLTEC）F18ab血清型标准菌株107/86基因组DNA为模板,利用PCR技术成功扩增出编码F18ab完整菌毛操纵子fed基因,克隆入表达载体pBR322,经限制性内切酶酶切分析,DNA琼脂糖电泳鉴定并结合序列测定分析,构建和筛选出含fed完整基因正确插入的pBR322-fed重组质粒,将上述重组质粒转化至不含任何菌毛结构的大肠杆菌SE5000,该表达重组菌能分别与兔抗F18ab亚单位蛋白FedF高免血清、鼠抗F18ab菌毛a单因子单克隆抗体、兔抗F18ab菌毛高免血清和抗F18ab菌毛IgG抗体产生明显的凝集反应。用热抽提法分别抽提和纯化SLTEC F18ab标准株107/86和重组菌SE5000（pBR322-fed）体外表达的F18ab菌毛,纯化菌毛经SDS-PAGE电泳和考马斯亮蓝染色获单一相对分子质量约为15 000蛋白条带。Western-blotting结果表明：兔抗F18ab菌毛高免血清能特异性识别SLTEC F18ab标准株107/86和重组菌SE5000（pBR322-fed）所提纯的单一主要结构蛋白。用重组菌SE5000（pBR322-fed）进行易感仔猪小肠上皮细胞体外黏附试验和黏附抑制试验,结果表明：重组菌SE5000（pBR322-fed）和SLTEC F18ab标准株107/86一样具有较强的黏附易感仔猪小肠上皮细胞的能力,而兔抗F18ab菌毛高免血清能有效地抑制上述重组菌SE5000（pBR322-fed）和SLTEC F18ab标准株107/86对易感仔猪小肠上皮细胞的黏附结合。  相似文献   

Effects of β₃ integrin on adhesion and migration of vascular smooth muscle cells induced by growth factor     

HAO Yu-bin  WEN Jin-kun  HAN Mei 《园艺学报》2004,20(3):335-338

AIM: To investigate the effect of platelet-derived growth factor (PDGF) on β₃ integrin gene expression and the role of β₃ integrin on adhesion, migration and proliferation of vascular smooth muscle cells (VSMC) induced by PDGF. METHODS: β₃ integxin gene expression was detected by RT-PCr. After β₃ integrin extracellular do-main was blocks, VSMC adhesio, migration and proliferation were measured by adhesion assay awound-culture model an [³H]-TSR incorporation respectively.RESULTS: After the interaction between β₃ integrin and extracellular matrix was blocked, VSMC proliferation was inhibited in some degree and the rate of [³H]-TdR incorporation into VSMC decreased 39%. The cell adhesion and migration were significantly inhibited when 10 mg/L anti-β₃ integrin antibody was added (P＜0.05). When VSMC were treated by PDGF for 6 hours, the expression of β₃ integrin gene was 87% higher than that of control. CONCLUSION: PDGF significantly induces expression of β₃ integrin gene in VSMC, and the interaction between β₃ integrin and ECM protein may play an important role in VSMC adhesion and migration.  相似文献   

药液在作物叶片的流失点和最大稳定持留量研究   总被引：30，自引：4，他引：26  

袁会珠  齐淑华  杨代斌 《农药学学报》2000,2(4):66-71

用微量称重法可以方便地测定作物叶片的流失点 (POR)和最大稳定持留量(Rm) ,用浸渍法和喷雾法测定的 Rm 结果不同。引用润湿方程的概念来分析影响 Rm 的规律 ,浸渍法测定的 Rm 与粘附张力有关 ,当接触角大于 90°,叶片表面不粘附液体 ,Rm 趋于零。用喷雾法测定作物叶片 Rm,结果显示与药液的粘附功 [γ× (COSθ+1) ]有关 ,即使接触角大于 90°时 ,由于粘附功大于零 ,Rm 值也大于零。对于水稻这样难润湿的作物叶片 ,清水中添加表面活性剂可以提高 Rm;反之 ,对于棉花、黄瓜这样的作物叶片 ,添加表面活性剂反而会降低 Rm。  相似文献