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排序方式: 共有26条查询结果,搜索用时 13 毫秒
1.
为了能够快速、准确判断药筒模块是否合格,实现检测的自动化,针对药筒模块中可燃性紧塞盖图像的特点和检测要求,在研究经典相关系数匹配算法基础上,采用了一种快速图像匹配算法,即通过减少相关系数计算量和模板搜索范围,在保证匹配准确度的前提下来提高图像匹配速度。实验和现场测试表明,使用该方法,匹配速度提高了近67%,实现了图像的快速匹配,软件误判率1%,满足实际生产要求。  相似文献   
2.
用核磁共振波谱和红外光谱对新疆小黄山地区原煤干馏的煤焦油进行了研究和相关结构参数的计算,并由此推测了其原煤的煤化程度和生烃能力. 结果表明其芳碳率farC为0.78,平均碳数N=1.64,取代指数σ为0.49, 缩合指数Q为0.51. 与缩合芳香核上连接的烷基侧链较多且链长较短. 用OPUS软件,选择了5个红外光谱参数I1~I5,对谱图进行了矢量归一化并积分,获得了有关IR的部分结构参数. 由NMR和IR的结构参数,判定了小黄山原煤的变质程度为中等,其类型属于以镜质体为主的腐殖煤,由生烃机理推测其原煤的生气潜力大于生油潜力,其生气潜力碳主要为甲基单元,适宜做煤制气的原料.  相似文献   
3.
Meng  Ling-pu  Chen  Xiao-wei  Lin  Yuan-fei  Li  Liang-bin 《高分子科学》2017,35(9):1122-1131
Young's modulus of biaxially oriented polypropylene (BOPP) films prepared with homemade film stretcher was investigated,which can be used to indicate the softness of fihns.It was found that the modulus of films was decreased by about 69% as the content of polyethylene (PE) added into polypropylene (PP) reached 30%.Also,increasing draw temperature can induce lower stress level during stretching,which may lead to the formation of crystals with low orientation level and thus decreased modulus of films.Based on laboratory study,BOPP films produced on commercial line were studied by differential scanning calorimetry (DSC),wide and small-angle X-ray scattering (WAXS,SAXS) with varying contents of PE.SAXS results show that the crystals are oriented in both machine direction (MD) and transverse direction (TD),and the crystals are more oriented in TD than MD according to the WAXS results for all films.Also,the orientation parameter of crystal along TD increases from 0.68 to 0.83 as the contents of PE increase from 0% to 25%.Meanwhile,the modulus of films in MD declines with increase of PE contents generally,improving the film softness.Orientation of crystals is thus an effective structure parameter to adjust the film softness.The relationship of processing-structure-property is also established.  相似文献   
4.
李良彬 《高分子科学》2015,33(5):754-762
A biaxial stretching equipment was designed and constructed to enable fundamental studies of the relationship between film processing conditions and structures of oriented film products. With programmable drive motors and scissorlike mechanism, all stretching modes, including uniaxial stretching with constant and free width, simultaneous and sequential biaxial stretching, can be applied to a square-shaped sheet. Parameters related to film stretching manufacturing, such as temperature, draw ratio and stretching speed can be set independently to meet the requirement of different polymers. The force information during stretching is recorded by two miniature tension sensors in two directions independently, which can monitor the mechanical stimulus and stress response. Using this equipment, experiments are conducted to investigate the influence of stretching parameters on the structure of polypropylene films, which provides an effective method to tailor the processing conditions to obtain the films with desired properties.  相似文献   
5.
如何在确保边缘精确定位的同时,最大程度地抑制噪声以及图像灰度不均匀所产生的伪边缘点,是当前边缘检测所面临的难题。针对此问题,提出了多尺度张量的边缘检测算法,这种算法可以在不同尺度下获取更丰富的局部结构信息。选取适当的阈值,滤除噪声点和伪边缘,从而得到细节丰富的边缘。实验证明该方法得到的边缘细节丰富,且抗噪声性能较好。  相似文献   
6.
With the concept of super-atom, first principles calculations propose a new type of super stable cage clusters AlnH3n that are much more energetic stable than the well established clusters, AlnHn+2. In the new clusters, the aluminum core-frame acts as a super-atom with n vertexes and 2n Al-Al edges, which allow to adsorb n hydrogen atoms at the top-site and 2n at the bridge-site. Using Al12H36 as the basic unit, stable chain structures, (Al12H36)m, have been constructed following the same connection mechanism as for (AlH3)n linear polymeric structures. Apart from high hydrogen percentage per molecule, calculations have shown that these new clusters possess large heat of formation values and their combustion heat is about 4.8 times of the methane, making them a promising high energy density material.  相似文献   
7.
刘峰  王稷  丁洁  徐圆飞 《应用光学》2013,34(1):32-37
设计一款应用于多发射天线多接收天线自由空间激光通信系统中的折射式光学接收天线。天线焦距120.02 mm,相对孔径1∶1.13,工作波长为850 nm,波长范围覆盖820 nm ~880 nm,在50 lp/mm频率处0视场的MTF为0.5。接收天线可以在发射天线移动48 mm范围内利用光敏面直径为0.5 mm的雪崩光电二极管(APD)接收3 mrad发散角的光信号。该天线由两组、共4片球面透镜组成,结构简单,可实现对运动式发射天线的光信号的接收。  相似文献   
8.
胞嘧啶吸附在粗糙银和金电极上的表面增强拉曼光谱   总被引:4,自引:3,他引:1  
利用电化学伏安方法和表面增强拉曼光谱(SERS)技术研究了在-1.0V~0V的电位区间内胞嘧啶在粗糙银电极和金电极表面上的吸附行为。结果表明,在所研究的电位区间,胞嘧啶通过N3位垂直吸附在粗糙银和金电极表面,且当电位负移时吸附作用减弱。  相似文献   
9.
研究了飞秒脉冲经过光子晶体光纤时超连续谱产生的物理机制。采用输出波长可调谐的钛宝石光参量放大器作为泵浦源,光纤光谱仪测量不同泵浦功率和不同泵浦波长条件下光子晶体光纤产生的超连续谱的光谱图,对进行了归一化处理后的不同泵浦功率和不同泵浦波长条件下的超连续谱进行对比,分析影响光子晶体光纤超连续谱差异的物理机制。实验结果表明,当泵浦波长不变时,随着入射泵浦脉冲平均功率的增大,波峰增多,谱宽也逐渐加宽并伴随着出现能量向短波方向集中的现象,泵浦功率到达一定强度时,超连续谱的宽度最后到达饱和,谱的包络趋于稳定;入射光功率稳定在300 mW时,超连续谱的宽度和形状皆受到泵浦波长影响,在760~840 nm范围内,泵浦波长越长,波峰数越多,泵浦脉冲波长离零色散点越近,光子晶体光纤产生的超连续谱谱宽会越宽,超连续谱的形状相对越平坦。  相似文献   
10.
采用电子束(EB)对聚丙烯腈/聚氧化乙烯(PAN/PEO)凝胶电解质进行了剂量为13~260 kGy的辐照, 并对辐照改性的电解质组装的染料敏化太阳电池(DSSC)进行了性能测量。 结果表明, 改性后的DSSC的光电转化效率比改性前的高; 并且随EB辐照剂量的增加, DSSC效率先迅速增加(0~65 kGy), 然后缓慢减小(65~130 kGy)直至趋于一个平衡值(130~260 kGy)。 提升DSSC效率的最佳辐照剂量为65 kGy, 此时效率提高了约36%。 对比DSSC短路电流、 开路电压和填充因子随辐照剂量的变化, 发现DSSC效率的提高主要是由短路电流的提高引起的。 测量表明, 辐照改性后的DSSC时间稳定性得到了改善, 并且辐照剂量越高, 稳定性的改善越明显。 In this work, PAN/PEO (polyacrylonitrile/polyethylene oxide) based gel electrolyte was irradiated by electron beam (EB) with dose from 13 to 260 kGy. Then, DSSC (dye sensitized solar cell) was fabricated by the irradiated electrolyte and characterized. The results show that the efficiency of the DSSC fabricated by irradiated electrolyte is promoted comparing with DSSC fabricated by un irradiated electrolyte. And with irradiation dose increasing, the DSSC efficiency increases rapidly at first (0~65 kGy), then, drops down slowly (65~130 kGy), finally trends to a stable value (130~260 kGy). It indicates that there is an optimal irradiation dose, at which the promotion of DSSC efficiency is the highest, approximate 36%. Observed from the change of short circuit current, open circuit voltage and fill factor, short circuit current promotion by EB irradiation is found to be the main reason of DSSC performance promotion. The time stability measurement of the DSSC indicates that EB irradiation on PAN/PEO electrolyte reduces the loss of efficiency and the limiting effects become more apparent as the irradiation dose increases.  相似文献   
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