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针对页岩油储层矿物组分复杂多样、矿物体积含量模型不统一、矿物组分准确定量评价困难等问题,以济阳坳陷陆相页岩油储层的岩心X衍射全岩矿物岩心分析和薄片鉴定等实验资料为基础,引入有机骨架,构建页岩油储层“双骨架”矿物组分岩石物理体积模型,在经过储层三孔隙度校正之后,采用最小二乘法-奇异值分解最优化反演方法计算页岩油储层有机骨架和无机骨架矿物组分体积含量。研究表明,采用最优化反演方法计算得到的矿物体积含量与X衍射测量结果相关性达到0.60以上,并在实际井中得到验证应用。研究成果可为页岩油储层精细评价提供有力支撑。 相似文献
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Quan Nguyen Minh Quoc Dat Lai Hoang Nguy Minh Minh Tu Tran Kieu Ngoc Lam Gia Uyen Le My Phung Hang Hoang Dung Nguyen Tran Diem Ai Chau Ngoc Thuc Trinh Doan 《International Journal of Food Science & Technology》2022,57(7):4507-4517
To prevent the adulteration of agricultural resources and provide a solution to enhance the green coffee bean supply chain, authentication using the near-infrared spectroscopy (NIRS) technique was investigated. Partial least square with discrimination analysis (PLS-DA) models combined with various preprocessing methods were built from NIR spectra of 153 Vietnamese green coffee samples. The model combined with the standard normal variate and the first order of derivative yielded excellent performance in predicting coffee species with the error cross-validation of 0.0261. PLS-DA model of mean centre and first-order derivative spectra also yielded good performance in verifying geographical indication of green coffee with the error of 0.0656. By contrast, the predicting abilities of post-harvest methods were poor. The overall results showed a high potential of the NIRS in online authentication practices. 相似文献
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针对控制棒驱动机构(CRDM)机电响应时间快且测试环境存在噪声干扰等问题,搭建了一套集PXI数据采集硬件平台和MATLAB数据分析的快速机电响应时间测试系统,能够实现对高频控制棒棒位实时信号的快速采集。利用滑动平均滤波和分区间拟合方法对棒位位移信号进行滤波和拟合,并利用快速傅里叶变换(FFT)频谱分析法验证去噪效果。结果表明,本套测试系统能被成功应用于钍基熔盐液态堆(TMSR-LF1)第一停堆系统CRDM的机电响应时间测试中,在可行性、可靠性和可用性等方面均满足CRDM机电响应时间测试要求。 相似文献
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建立了行星齿轮-转子系统的非线性动力学模型,系统模型将内啮合刚度嵌入齿圈刚度进行建模,考虑了转子扭转效应、齿侧间隙、时变啮合刚度和综合传动误差等因素.采用分岔图、最大李雅普诺夫指数(LLE)、庞加莱截面图和相图来分析响应特征.研究齿轮与转子间扭转振动位移响应,分析了旋翼轴与传动轴扭转刚度比变化影响规律.研究发现,系统具有非线性动力学特性,通过准周期分岔和倍周期分岔进入混沌运动,获得了系统避免失稳的刚度比阈值区间.研究为直升机主减速器行星齿轮-转子系统的动力学设计和扭转振动控制提供了参考. 相似文献
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Hengtao Wang Hui Chen Weicheng Xie Hanjian Lai Tingxing Zhao Yulin Zhu Lin Chen Chunxian Ke Nan Zheng Feng He 《Advanced functional materials》2021,31(26):2100877
The design of polymer acceptors plays an essential role in the performance of all-polymer solar cells. Recently, the strategy of polymerized small molecules has achieved great success, but most polymers are synthesized from the mixed monomers, which seriously affects batch-to-batch reproducibility. Here, a method to separate γ-Br-IC or δ-Br-IC in gram scale and apply the strategy of monomer configurational control in which two isomeric polymeric acceptors (PBTIC-γ-2F2T and PBTIC-δ-2F2T) are produced is reported. As a comparison, PBTIC-m-2F2T from the mixed monomers is also synthesized. The γ-position based polymer (PBTIC-γ-2F2T) shows good solubility and achieves the best power conversion efficiency of 14.34% with a high open-circuit voltage of 0.95 V when blended with PM6, which is among the highest values recorded to date, while the δ-position based isomer (PBTIC-δ-2F2T) is insoluble and cannot be processed after parallel polymerization. The mixed-isomers based polymer, PBTIC-m-2F2T, shows better processing capability but has a low efficiency of 3.26%. Further investigation shows that precise control of configuration helps to improve the regularity of the polymer chain and reduce the π–π stacking distance. These results demonstrate that the configurational control affords a promising strategy to achieve high-performance polymer acceptors. 相似文献
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Shucheng Qin Zhenrong Jia Lei Meng Can Zhu Wenbin Lai Jinyuan Zhang Wenchao Huang Chenkai Sun Beibei Qiu Yongfang Li 《Advanced functional materials》2021,31(25):2102361
Organic solar cells (OSCs) have recently reached a remarkably high efficiency and become a promising technology for commercial application. However, OSCs with top efficiency are mostly processed by halogenated solvents and with additives that are not environmentally friendly, which hinders large-scale manufacture. In this study, high-performance tandem OSCs, based on polymer donors and two small-molecule acceptors with different bandgaps, are fabricated by solution processing with non-halogenated solvents without additive. Importantly, the two active layers developed from non-halogenated solvents show better phase segregation and charge transport properties, leading to superior performance than halogenated ones. As a result, a tandem OSC with high efficiency of up to 16.67% is obtained, showing unique advantages in future massive production. 相似文献
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