热的产生
- 与 热的产生 相关的网络例句 [注:此内容来源于网络,仅供参考]
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Experimental accuracy and repetition of FBG temperature sensitivity and compensation were discussed.have selected several materials which has bigger coefficient of expansion to do packaging components, have made many temperature experiments, there have not flaws, such as aging, crackle, absciss layer, packaging materials have good temperature sensitivity and compatibility with optical fiber;have designed the simple and practical packaging components, have performed a serials of experiments about accuracy and repetition of FBG wave-length, have obtained the first step conclusion;have analyzed the result and made comparison between the result of different experiment, have summarized the best packaging effect and several rules to reduce mistskes.
本文所做的主要工作包括以下几个内容:一、选取了常见的热膨胀系数大的材料制作封装元件,经过多次一80℃到80℃反复测试,封装元件没有出现老化开裂、封装裂纹、空洞、离层等缺陷,封装材料具有良好的温敏稳定性及复用性,与光纤相容性较好;二、对光纤光栅进行简单、实用的封装处理,就封装效果的优劣性、波长测量的准确度、重复性和封装时产生的波长损失等方面进行了一系列的实验,得出了初步的结论;三、对温敏和温度补偿式封装的实验数据进行了详细的分析和对比,从数字上对温变过程中光纤光栅中心波长的改变及温变曲线进行了定量的分析,在大量实验数据分析结果的基础上,总结出哪种材料封装效果更好,以及如何有效的减小实验误差。
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The vapour and plasma ignition times of the target are got based on the equation of heat conduction and cascade model. We suppose that the plasma is ignited when 210 generations of new electrons are born in vapour generation time. The influence of temperature on the thermodynamics and optics parameters of material also have been considered in the model. The resulting theory has good agreement with the experiment and overseas report. A blade method to measure the laser spot is given in this paper with validation and error analysis. The plasma threshold of metals in atmosphere and water ambients both are diagnosed with the light deflection and piezoelectric transducer. A Q-switched pulsed Nd:YAG laser operating at infrared (1064nm), visible(532nm) and ultraviolet (355nm) wavelengths has been used. Al、Fe、Cu are used as targets and get a similar results with both method. Theoretical and experimental analyses are applied on the influence of wavelength on the threshold have been done, both of which have shown that the plasma threshold of metals decrease as the laser wavelength increases; The plasma threshold of metals are higher in water than in air and the pressure of the shock wave in water is five times higher than in air.
从热传导方程和雪崩电离机制出发,假设当电子增值2~(10)倍时,考虑了温度对材料热力学和光学参数的影响时,得到了气化和等离子体点燃的时间,利用该模型进行计算得到的结果与国内外报道及自行通过实验测得的阈值基本一致;提出了利用刀刃法测量激光光斑面积的方法,并通过实验进行了验证和误差分析;利用光偏转装置和压电换能器分别对空气和水中金属等离子体点燃阈值进行了实验诊断,激光器均为调Q—YAG激光器(波长1064nm,532nm,355nm,脉宽10ns),靶材分别为Al、Fe和Cu,两种测试方法得到的等离子体点燃阈值基本一致;本文从实验和理论计算两个方面讨论了波长对等离子体点燃阈值的影响,均得到了等离子体点燃阈值随着波长的增加而减小的结论;对空气中和水中不同环境下金属等离子体的点燃阈值进行了比较研究,得到了金属在水中的等离子体点燃阈值比空气中的大,且水中产生的冲击波的压强是空气中的5倍左右的结论。
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The characteristic of machined surface of high speed machining aluminum alloy 7050-T7451 is researched by micrographic experiments and analysis. The formation mechanics of machined metamorphism layer has been analyzed and studied. The dislocation-energy model in machined metamorphism layer was established and applied to explain the micrographic mechanics work-hardening using the thermo-mechanical coupling deformation theory and dislocation theory. The experimental results show that the interaction of high dislocation density effect on hardening is more remarkable than that of thermal stress in high speed machining.
利用显微观察方法对铝合金7050-T7451高速铣削加工的工件表面断面和不同深度的表层的微观形貌特征进行系统的研究,确定了高速切削加工铝合金7050-T7451的表面变质层深度为30~35μm;应用位错能量研究了高速铣削加工过程的热力耦合对变质层的影响机理,并通过微观形貌观察证明:与普通切削相比,高速铣削表层塑性变形的能量和位错密度更高;建立了位错密度的加工硬化的动力学模型,研究了加工硬化的热-力耦合形成机理;对微观裂纹的形成机理进行了理论分析,证明位错密度高的高速切削过程中较低速加工更容易产生明显的微裂纹,从分子级乃至原子级的水平进一步揭示高速切削加工表面变质层的形成特征。
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Therelationship between the turbulent kinetic energy and its dissipation rate,whichis widely used to parameterize the dissipation rate in turbulence closure models,is found to hold well for both reversing and rotating flows,but with differentcoefficients.Microstructure profiling measurements at two comparative stations (a deepercentral basin and a local shelf break) in the stratified Yellow Sea are analyzed,with emphasis on tidal and internal-wave induced turbulence near the bottomand in the pyenocline.The water column has a distinct three-layer thermohaline structure,consisting of weakly stratified surface and bottom boundary layers anda narrow sharp pycnocline.Turbulence in the surface layer is controlled by thediurnal cycle of buoyancy flux and wind forcing at the sea surface.while thebottom stress induced by barotropic tidal eurrents dominates turbulence in thebottom boundary layer.The maximum level at which the tidally enhanced mixingcan affect generally depends on the magnitude of the tidal current,and it canbe up to 10-15 m in the Yellow Sea.This suggests that,in the deeper regionsof the shelf seas,turbulent dissipation and mixing are very weak at the levelsbetween the near-bottom tidally enhanced layer and the pycnocline.Therefore,these levels provide a significant bottle neck for the vertical exchanges.In theshallow regions,however,the tidally-induced turbulence can occupy the wholewater colum below the pycnocline.A quarter-diurnal periodicities of the turbulentdissipation rate and eddy diffusivity are found at different heights with evidenttime lag.In the relatively flat central basin,the pycnocline is essentially non-turbulent and internal-wave activity is very weak.Therefore,vertical fluxes acrossthe pycnocline decreased to molecular levels.In contrast,internal waves of variousperiods can be always found near the local shelf break.
对强层化季节黄海两对比性站位(分别位于中央海盆区与局地陆坡区)处层化、内波以及湍流混合特征的研究结果表明:1、强层化季节的陆架海水体一般呈现显著的三层热盐结构,在水体近乎混合均匀的上混合层与潮流底边界层之间为强跃层;2、近表层水体的湍流混合强度主要由海表浮力通量的日变化与海表风强迫控制,而在潮流底边界层内,潮混合是水体热量、物质、动量与能量垂直交换的主要机制;3、潮混合影响的深度由潮流大小决定,在黄海,一般可达10-15 m,因此,在水深较深的区域,在跃层与潮混合所至深度范围的上界之间存在湍流混合非常弱的区域,这显著抑制水体内物质的垂直通量,为物质垂直交换的瓶颈,而在水深较浅的区域,潮混合影响范围可至跃层底部,因此物质在跃层以下整个水体中混合非常均匀,当跃层内间歇性强混合发生时,可以产生显著的跨跃层物质输运;4、近底潮致强湍流耗散缓慢地向上传播,底上不同深度处垂直湍扩散系数也具有显著的位相差异,且二者均随时间呈现四分之一周日周期的变化;5、在地形较为平坦的中央海盆区,内波活动非常微弱,因此跃层内湍流混合非常弱,垂直扩散系数为分子扩散水平,跨跃层物质通量受到显著抑制,而在地形变化较为显著的局地陆坡区,内波活动非常活跃,除内潮的影响外,高频内波与内孤立波的影响也很显著,因此跃层内存在很强的间歇性强混合,内孤立波存在的区域,水体湍流混合显著增强。
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The plasma ignition threshold of metal is got through experimental and numerical study. The vapour and plasma ignition times of the target are got based on the equation of heat conduction and cascade model. We suppose that the plasma is ignited when generations of new electrons are born in vapour generation time. The influence of temperature on the thermodynamics and optics parameters of material also have been considered in the model. The resulting theory has good agreement with the experiment and overseas report. A blade method to measure the laser spot is given in this paper with validation and error analysis. The plasma threshold of metals in atmosphere and water ambients both are diagnosed with the light deflection and piezoelectric transducer. A Q-switched pulsed Nd:YAG laser operating at infrared (1064nm), visible(532nm) and ultraviolet (355nm) wavelengths has been used. Al、Fe、Cu are used as targets and get a similar results with both method. Theoretical and experimental analyses are applied on the influence of wavelength on the threshold have been done, both of which have shown that the plasma threshold of metals decrease as the laser wavelength increases; The plasma threshold of metals are higher in water than in air and the pressure of the shock wave in water is five times higher than in air .
从热传导方程和雪崩电离机制出发,假设当电子增值210倍时,考虑了温度对材料热力学和光学参数的影响时,得到了气化和等离子体点燃的时间,利用该模型进行计算得到的结果与国内外报道及自行通过实验测得的阈值基本一致;提出了利用刀刃法测量激光光斑面积的方法,并通过实验进行了验证和误差分析;利用光偏转装置和压电换能器分别对空气和水中金属等离子体点燃阈值进行了实验诊断,激光器均为调Q-YAG激光器(波长1064nm,532nm,355nm,脉宽10ns),靶材分别为Al、Fe和Cu,两种测试方法得到的等离子体点燃阈值基本一致;本文从实验和理论计算两个方面讨论了波长对等离子体点燃阈值的影响,均得到了等离子体点燃阈值随著波长的增加而减小的结论;对空气中和水中不同环境下金属等离子体的点燃阈值进行了比较研究,得到了金属在水中的等离子体点燃阈值比空气中的大,且水中产生的冲击波的压强是空气中的5倍左右的结论。
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Based on the data analysis and numerical simulation, the Arctic sea ice climate variability was researched, the result were as following:(1) The analysis on the seasonal cycle of the Arctic Ocean and atmosphere showed that: The seasonal surface wind is somewhat trade wind like in some regions in the Arctic. The surface air temperature is robustly determined from the underlying environments such as sea ice and Greenland glaciers. In the sea ice region the precipitation rate is larger than that of evaporation. Furthermore, the Arctic Ocean hydrology is profoundly influenced by the surrounding rivers discharge. These are the decisive factors on the ocean salinity pattern. Sea ice flux through the Fram Strait is larger in winter than in summer. From the 40s in the 20th century on, the ice volume flux has an increasing trend. The Arctic rivers flood season is about the melt period, the winter rivers discharge has a significant increasing. Correlation analysis shows that 7 to 10 years is a characteristic time scale that rivers discharge leads Fram Strait ice volume export.(2) Considering 9 major arctic rivers, the Arctic Ocean circulation was simulated through BOM. The result shows that: The BOM can reproduce the main Arctic Ocean circulation pattern. The"Islandization"which is commonly used in OGCMs to treat the North Pole, not only influences the ocean current near the pole, but also influences the current in the Northern Atlantic Ocean, thus the bogus island might influence global climate through thermohaline circulation in the Atlantic Ocean.
在资料分析和数值模拟的基础上,对北极海冰的气候变率进行了深入的研究,结果如下:(1)对北极地区大气和海洋季节循环特征的分析表明,气候平均风场在部分地区具有&信风&的性质;而气温场与海冰分布及格陵兰半岛冰原的下垫面特征有密切关系;在北极海冰区的降水量大于蒸发量,并且在全球大洋中北冰洋受到河流径流的影响最大,对北冰洋的盐度分布有决定作用;通过弗瑞姆海峡的海冰通量在冬半年大于夏半年,并且从20世纪40年代起,海冰的体积输送有增加趋势;北极河流的汛期主要在融化季节,冬季的河流流量有显著增加的趋势;相关分析表明7到10年是北极河流流量影响弗瑞姆海峡海冰体积输送的一个特征时间尺度;(2)采用BOM海洋模式对北冰洋海洋环流进行了模拟研究,在模式中考虑了北极9条主要河流的作用,结果表明该海洋模式可以较好模拟出北冰洋海洋环流的基本特征;多数大洋环流模式采用&北极岛化&的方法处理北极点,模拟结果表明&北极岛化&不仅影响到极点附近的海流,还会对相对较远的北大西洋海流造成影响,并可能通过大西洋的热盐环流对全球气候产生影响;(3)采用CSIM4海冰模式对北极海冰的气候态进行了模拟。
- 推荐网络例句
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The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.
采用不同浓度K2CrO4(0,0.4,0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗,测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。
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By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.
通过分析数学形态学在图像中的理论基础,研究二值图像的形态分析算法,探讨最小结构元素的两种基本形态:膨胀和腐蚀;分析了数学形态学复杂算法的基本原理,把数学形态学的部分并行处理理念引入到家实际应用中。
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Have a good policy environment, real estate, secondary and tertiary markets can develop more rapidly and improved.
有一个良好的政策环境,房地产,二级和三级市场的发展更加迅速改善。