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为研究秸秆燃烧中KCl的逸出规律,对KCl,KCl和SiO2,KCl和K2SO4,KCl、K2SO4和SiO2,纯秸秆灰(玉米秸/麦秸/稻秸)进行了热重实验。发现秸秆燃烧中KCl共熔后的蒸发是钾逸出的主要方式之一。结合KCl饱和蒸气压规律、拉瓦尔定律等,建立了秸秆燃烧中KCl逸出的原位共熔蒸发模型。应用气相区解析解和气液共存区隐式数值求解,编程对KCl逸出过程进行了分析。结果表明:固相温度控制在700℃以下可有效控制KCl的逸出。原位共熔蒸发模型可描述KCl逸出特性和趋势(多数情况下相对误差<15%),获得物性数据可进一步提高模型精度。 相似文献
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SrB6010:Tb phosphor was synthesized by high-temperature solid state reaction. The influences of Ce or Li as a co-dopant, Tb concentration and irradiation dose exposure on TL of SrB6010 : Tb were investigated. Results show that Ce or Li as a co-dopant can not improve the sensitivity of SrB6010:Tb phosphor. TL response depends on Tb concentration and 0.02 is the optimum in the concentration range from 0.01 to 0.10. Using the optimum Tb concentration, we calculated the kinetic parameters of SrB6010:Tb employing the peak shape method, and suggested the phosphor obeying the second order kinetics. TL emission intensity is linearly dependent on the irradiation dose within the dose range of 50 - 200 Gy. The characteristic Tb^3+ ion emission was observed in TL emission spectrum. 相似文献
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随着燃料电池在客车上的应用不断深入,其低温环境下冷启动问题逐渐凸显。为了提高燃料电池客车的启动速度,使电池更快地工作在合理的温度范围内同时降低冷启动过程的能耗,将相变材料(PCM)引入电堆冷启动系统,利用PCM可吸收电堆工作废热的特性,在冷启动时将废热放出加热电堆。基于仿真平台搭建电堆冷启动系统模型,对比分析了正温度系数热敏电阻(PTC)独立加热、PCM独立加热和PCM-PTC联合加热的温升变化和能耗特性。3种加热方式均使80 kW电堆从–20 ℃升高到10 ℃,PTC的功率为12 kW,PCM采用石蜡/膨胀石墨复合相变材料(CPCM)。在联合加热方式下,分析了PCM质量对冷启动时间、节能率和潜热利用率的影响。结果表明:PCM-PTC联合加热方式较PTC独立加热节省约33.46%能耗,启动时间缩短了37.40%,较PCM独立加热启动时间缩短了61.00%;随着PCM质量的增加,冷启动时间缩短,系统节能率增加,但是PCM的潜热利用率却在下降。PCM辅助的冷启动系统为燃料电池发动机在低温环境下快速启动和节能提供了思路。 相似文献
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Novel red-emitting Eu3+, Sm3+ singly doped and co-doped Ca14Mg2(SiO4)8 phosphors were prepared by conventional solid- state reaction. Powder X-ray diffraction patterns were employed to confirm phase pu... 相似文献
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引起面板堆石坝沉降变形的环境因素复杂,观测数据呈现出明显的噪声干扰特性,限制了数学模型拟合及预测的精度。对原始信号进行小波变换可有效分解其中的有用信号和噪声,因此,引入小波变换理论建立了基于小波阈值去噪的数学模型,并对面板堆石坝(CFRD)的沉降变形实测数据实施去噪,再对去噪后的数据进行高斯过程回归(GPR),建立了预测堆石坝沉降变形的模型。依托CFRD的实测沉降变形资料,采用Wavelet-GPR模型对大坝沉降进行了拟合与预测,并与未进行去噪的GPR模型计算结果进行对比。结果表明:Wavelet-GPR模型观测值与预测值的残差符合正态分布,去噪后学习段的均方根误差(RMSE)由0.928 7 mm减小至0.457 7 mm,平均绝对误差(MAE)由0.485 0 mm减小至0.330 6 mm;预测段的RMSE由1.308 9 mm减小至0.917 6 mm,MAE由0.926 3 mm减小至0.730 3 mm;且去噪后模型的样本观测值个数在其预测值95%置信范围内的占比有明显提升。因此,利用小波阈值去噪对实测沉降数据进行降噪处理能够降低噪声导致的数据观测值与真实值之间的误差,Wa... 相似文献
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在测度中国30省市电热行业煤炭利用效率的基础上,运用ESDA模型以及空间误差模型研究中国电热行业煤炭利用效率的空间特征以及影响因素。研究结果表明:①2001—2015年间中国电热行业煤炭利用效率水平不高,且呈现出小幅度下降趋势|30省市的煤炭利用效率均未实现有效,且存在明显差异性,呈现出东部>中部>西部的分布格局。②中国省际电热行业煤炭利用效率呈现正向空间自相关性,且存在明显的集聚状态,近邻效应显著。③中国省际电热行业煤炭利用效率的主要影响因素有工业发展水平、产业集聚、技术进步、交通及政府规制。 相似文献
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The thermoluminescence (TL) properties of Ce3+ doped NaSr4(BO3)3 phosphor under the β-ray irradiation were reported. The polycrystalline sample was synthesized by high temperature solid-state reaction. The TL glow curve of NaSr4(BO3)3:Ce3+ phosphor was com-posed of only one peak. TL kinetic parameters of NaSr4(BO3)3:Ce3+ were deduced by the peak shape method, the activation energy (E) was 0.590 eV and the frequency factor was 1.008×106s-1. TL dose response was linear in the range of measurement. The 3-dimensional (3D) TL emission spectrum was also recorded, the emission spectrum consisted of two bands located at 441 and 479 nm respectively, corresponding to the characteristic 4f05d1→2F(5/2,7/2) transitions of the Ce3+ ion. The fading behavior of the NaSr4(BO3)3:Ce3+ phosphor over a period of 15 d was also studied. 相似文献
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Thermoluminescence(TL)isakindofcommon phenomenoninnatureandhasbeenextensivelyap pliedinradiationdosimetry,archaeologydatingand geology.TLmaterialsdopedwithrareearthssuchas MgB4O7∶Dy TmandCaSO4∶Dyetc.areutilizedasra diationmeasurementinradiationdosimetryfielddueto theircharacteristicsoftissueequivalenceandhigher sensitivity,respectively.However,anidealTLphos phorwithtissueequivalence,highsensitivity,simple glowcurvestructure,andexcellentstability,etc.has notbeenfoundyet.ThepropertiesofT… 相似文献