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1.
导出了奠定前置反射器辐射温度计理论基础的被围表面有效发射率新公式。此式也是红外辐射测温技术的基本公式之一。被测表面在反射器作用下会引起表面温升现象,由此根据所拟定的边界条件和初始条件解一维热传导方程,求得被测表面温升的理论公式。上述两式都与实验结果相吻合。为深入了解该类型仪表的测温原理,对该类型辐射测温仪表的系统误差进行了分析,各项有效发射率增量的累计与理论有效发射率之和(实际有效发射率)同实际测量误差相比,吻合较好。此种辐射温度计在1000℃时,误差在±10℃以内。  相似文献   

2.
本文提出辐射测温的一种简单线性化公式。该方法将信号电压直接作对数运算,便于数字式温度显示或其它线性仪表指示。计算机模拟表明,在常用的红外测温波段和温度量程范围内可获得较好的精度,适合于模拟电路结构的辐射温度计使用。  相似文献   

3.
本文介绍的三波长辐射测温法是以普朗克公式和电动力学中Hagen-Rubens公式为理论基础的非接触测温方法。主要解决被测对象表面发射率很低或不确定时的辐射测温问题。文章着重介绍了仪表的工作原理和结构,分析了仪表的精度、灵敏度和刻度方法。最后给出了实验结果,对理论分析予以验证。  相似文献   

4.
数字式测温仪表已成为自动化生产过程中最为普通的仪表,但工业用数字测温仪表在某些场合受到限制,特别是在测量精度方面.作者研制了多种高精度数字测温仪表,经过一年运行后,复测仪表精度,误差不超过上0.1℃,许多点的重复性在0.03℃内.本文着重论述测温传感器的选择,铂电阻的非线性校正,R—V变换电路选择以及前置电路的设计等.  相似文献   

5.
本文介绍了用热电偶法测量切削温度时,测温传感器及测温仪表的动态特性和滞后误差;并对现有测量切削温度的标定与实验方法进行了一些评述。  相似文献   

6.
该测温仪由光钎传感器和二次仪表两大部分组成。传感器采用了光钎耦合与传输的先进技术,用10m光钎作为耦合传输元件,将探头与光电元件分离。用压缩空气冷却光耦合器和光纤,并清洗光路,使探头能长期逼近被测铁水表面,光电元件离开测温现场,埋入地下,同时,大大地提高了抗干扰能力。测温仪信号处理与输出采用了模拟数字显示和单片机大屏幕显示装置,并配有记录仪,性能稳定可靠,漂移小,具有黑度系数补偿,峰值保持及峰值平均值,实现了仪表的智能化,为高炉炼铁计算机控制系统提供了先决条件。 该测量仪在承德钢铁厂炼铁厂2~#和3~#高炉安装运行了五个月。通过对铁水及炉渣温度测量的实践证明,仪表性能稳定可靠,测量准确,使用方便,能满足炼铁工艺生产要  相似文献   

7.
在简述延迟线型SAW传感器测量温度工作原理的基础上,提出了测温仪的硬件结构,深入研究了测温仪主要组成单元的关键技术,设计和研发出SAW传感器步进频率测温仪系统.测温仪的充分测试结果验证了这些关键技术对于提高测温精度起着重要作用.  相似文献   

8.
在环境辐射及物体发射率未知的情况下,直接用辐射测温仪测出物体的真实温度,是长期以来未解决的问题。本文假定将两个具有给定温度及发射率的罩子罩在物体上,并利用安装在罩子顶上开孔处的二台辐射测温仪分别测得两个表现信号,利用这两个信号及我们推得的公式,可实时测出物体的发射率及真实温度。本文还给出了前置罩式辐射测温仪的信噪比及灵敏度公式。  相似文献   

9.
传统的惯性平台的标定方法存在很大的局限性.根据高精度惯性仪表的特性,对传统的误差模型适当地进行了简化,建立了供自标定使用的陀螺仪、加速度计误差模型;针对三框架四轴全姿态惯性平台,提出了一种七位置自标定方案;给出了公式解算方法及数据测试方法,占用时间约40 min,共分离出包括两个水平地速分量在内的20项误差系数.通过自标定时间、精度分析,表明该自标定方案有助于缩短平台的测试时间,提高武器系统的使用精度.  相似文献   

10.
提出了一种新的在线黑度测量的原理及方法。应用该方法在线测量了中厚钢板、轧辊和钢坯等表面全发射率(黑度)。该法需要两台前置反射器辐射温度计,一台带反射器,另一台带吸收器。根据两台仪表的读数可以建立两个电压信号方程式,解这两个方程便可求得温度和黑度的值。当被测表面温度为400℃以上,黑度为0.6以上时,系统误差可在5%以内。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

18.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

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