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1.
温度测量是工业、农业、国防和科研等部门最普遍的测量项目。在玻璃的生产过程中也不例外,处处都存在着温度测量过程,如:熔窑的温度测量、锡槽各区、退火窑的各区温度测量等等。在实际的测量过程中,由于被测的对象不同,以及测量条件的差异,尽管是测量同一参数,但其测量方法、测量设备、测量人员不一样,测量的结果都有可能与真实值不一致,这就存在着一个测量值接近于真实值的准确程度,即测量准确度的问题。在现场温度测量过程中,影响温度测量准确度的主要因素有测温仪表的基本误差和附加误差。  相似文献   

2.
针对水下生产控制系统温度测量系统中单个传感器易受水下复杂环境影响,出现温漂、测量精度低等问题,设计了一种双冗余温度测量传感器(采用两个热敏元件进行温度测量)。利用基于有偏卡尔曼的扩维融合方法进行数据处理,提高传感器融合测量精度。定义一个相似矩阵,用于在融合之前剔除故障传感器的测量数据,进一步提高测量结果的可靠性。实验结果表明:双冗余温度测量传感器具有精度高、抗干扰性能强的优点。  相似文献   

3.
《塑料制造》2009,(10):54-54
测量时,使用投影仪测量非常方便,只要把工件放好,位置对准便可测量。然而,需要测量多个尺寸位置或大量检测时,便不太合适。碰到以上问题,人们常常会想起光学视像测量仪。它可以编程及进行自动测量,而且精度高,对于检测量大的工件,是最合适的选择。在价格方面,  相似文献   

4.
本发明提供了一种水质测量设备,无需依赖于测量条件下流入测量槽的水的流入速率,可以防止任何悬浮物在水的测量过程中的沉积,同时可以避免水质测量探针的检测部分附近的滞留点或卡曼涡流现象。本文提供的水质测量设备包括具有测量水入水口和出水口的水质测量槽。  相似文献   

5.
《塑料制造》2005,(7):25-29
人类社会的发展与进步,与测量技术密不可分,可以这样说,我们通过测量技术认识世界,大到宇宙天体,小到我们的生产、生活、学习的各个方面。无不与测量设备发生联系,在制造领域,测量技术的发展推动了制造业日新月异的变革,现代的测量技术,不是用简单的尺子,而是将“计算机作为仪器、软件作为仪器”,并紧紧依托网络传递信息的智能测量方式,这种测量为生产效率及产品质量的提高创造了先决条件,更为现代制造业的发展插上了腾飞的翅膀。测量技术不仅是产品品质评定的技术手段,而且是引导人们由宏观向微观,由粗略到精细,贯穿人类进步全过程的关键技术,更是全球经济迅猛发展的催化剂和核心推动力之一,模具作为高技术精密产业,更离不开现代测量技术的支持。  相似文献   

6.
叙述了电刷镀镀层测量的特殊性,即要求在加工过程中不破坏镀层的情况下具有较高的测量精度。目前常用的有电磁法、涡流法、X射线法、扫描电镜法等,其测量精度虽高,但价格昂贵,且不适合于现场的动态测量,而研制的DDC型在线自动测量装置却能满足上述要求,本文还叙述了DDC型镀层厚度自动测量装置的工作原理、结构与测量精度。  相似文献   

7.
地籍测量可以获取土地及其附着物的位置、权属界线、类型、面积等信息,在房地产开发中起到重要作用。无人机倾斜摄影测量技术弥补了传统摄影测量的局限性,在地籍测量中被广泛应用。为了采集到高精度的地籍测量数据,结合安溪县某村庄案例,对试验区无人机倾斜摄影地籍测量的重要环节进行分析。精度评定结果认为,影像分辨率控制在1.50cm以内时,试验区界址点中误差为±3.50cm,界址点间距中误差为±2.86cm,最终达到该试验区地籍测量的效果。  相似文献   

8.
未经过原油稳定处理的乍得原油、苏丹原油含有大量的轻组分,两种原油密封测量的凝点比常规测量的分别低2.5℃,1℃;在密封测量的初始温度以下1℃处,密封测量的粘度比常规测量的大;随着温度的降低,常规测量的粘度比密封测量的大,温度越低两者之间的差值越大。在28℃,51/s的条件下,苏丹原油密封测量与常规测量相比粘度减小47.71﹪;在26℃,51/s的条件下,乍得原油的减小64.93﹪  相似文献   

9.
基于机理分析,实现了催化裂化反应再生系统预测化率和产品产率的在线软测量,对软测量的算法设计,软测量算法的实现,现场软测量应用及验证予以叙述,表明具有一定的实有价值。  相似文献   

10.
采用NSKC-1型光透式粒度仪对水泥粒度分布及比表面进行了测定研究,介绍了测量的原理,确定了光透法测量水泥粒度的基本条件,着重研究了样品制备对测量影响,并对测试精度进行了评价,也对比表面的计算进行了讨论。结果表明,光透法测量水泥细度,同传统测试相比,操作简单,测量精度高,便于推广。  相似文献   

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12.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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14.
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

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17.
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

18.
Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

19.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

20.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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