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481.
Xiao Yuan Song Guoliang Lyu Qinggang 《Journal of Thermal Analysis and Calorimetry》2021,146(3):1245-1253
Journal of Thermal Analysis and Calorimetry - For realizing the coupling pyrolysis of coal and combustion of semi-coke, this paper explored the effect of pyrolysis temperature on the combustion... 相似文献
482.
o-Carborane-containing poly(hydroxy ethers)(P1, P2 and P3) were synthesized via "advancement reaction" of o-carborane-containing bisphenol(4) and diglycidyl ether of bisphenols(DGEBA and 1). FTIR and ~(1) H-, ~(13)C-, and ~(11) B-NMR were utilized to characterize the obtained polymers. TGA test was conducted under nitrogen and air. It is found that the shielding effect of carborane moiety on its adjacent aromatic structures contributes to high initial decomposition temperatures, while oxygen in air has an adverse effect on the initial decomposition temperature. The oxygen can combine with polymer chain to form peroxide and hydroperoxide groups, which are more reactive during the degradation process. Besides, o-carborane-containing poly(hydroxy ethers) have high char yield at elevated temperatures. The boron atom combines with oxygen from the polymer structure or/and from air, thus to form a three-dimensional network linked with B―O―B and B―C bonds, and retain the polymer weight to a large extent. 相似文献
483.
In situ NMR measurements of the diffusion coefficients,including an estimate of signal strength,of lithium ion conductor using diffusion-weighting pulse sequence are performed in this study.A cascade bilinear model is proposed to estimate the diffusion sensitivity factors of pulsed-field gradient using prior information of the electrochemical performance and Arrhenius constraint.The model postulates that the active lithium nuclei participating electrochemical reaction are relevant to the NMR signal intensity,when discharge rate or temperature condition is varying.The electrochemical data and the NMR signal strength show a highly fit with the proposed model according our simulation and experiments.Furthermore,the diffusion time is constrained by temperature based on Arrhenius equation of reaction rates dependence.An experimental calculation of Li_4Ti_5O_(12)(LTO)/carbon nanotubes(CNTs) with the electrolyte evaluating at 20 ℃ is presented,which the b factor is estimated by the discharge rate. 相似文献
484.
Li Chen Yinrun Lyu Chong Wang Jingzheng Wu Changyou Zhang Nasro Min-Allah Jamal Alhiyafi Yongji Wang 《Journal of Global Optimization》2017,69(1):69-102
Since Balas extended the classical linear programming problem to the disjunctive programming (DP) problem where the constraints are combinations of both logic AND and OR, many researchers explored this optimization problem under various theoretical or application scenarios such as generalized disjunctive programming (GDP), optimization modulo theories (OMT), robot path planning, real-time systems, etc. However, the possibility of combining these differently-described but form-equivalent problems into a single expression remains overlooked. The contribution of this paper is two folded. First, we convert the linear DP/GDP model, linear-arithmetic OMT problem and related application problems into an equivalent form, referred to as the linear optimization over arithmetic constraint formula (LOACF). Second, a tree-search-based algorithm named RS-LPT is proposed to solve LOACF. RS-LPT exploits the techniques of interval analysis and nonparametric estimation for reducing the search tree and lowering the number of visited nodes. Also, RS-LPT alleviates bad construction of search tree by backtracking and pruning dynamically. We evaluate RS-LPT against two most common DP/GDP methods, three state-of-the-art OMT solvers and the disjunctive transformation based method on optimization benchmarks with different types and scales. Our results favor RS-LPT as compared to existing competing methods, especially for large scale cases. 相似文献
485.
Transparent, flexible electronic skin holds a wide range of applications in robotics, humanmachine interfaces, artificial intelligence, prosthetics, and health monitoring. Silver nanowire are mechanically flexible and robust, which exhibit great potential in transparent and electricconducting thin film. Herein, we report on a silver-nanowire spray-coating and electrodemicrostructure replicating strategy to construct a transparent, flexible, and sensitive electronic skin device. The electronic skin device shows highly sensitive piezo-capacitance response to pressure. It is found that micropatterning the surface of dielectric layer polyurethane elastomer by replicating from microstructures of natural-existing surfaces such as lotus leaf, silk, and frosted glass can greatly enhance the piezo-capacitance performance of the device. The microstructured pressure sensors based on silver nanowire exhibit good transparency, excellent flexibility, wide pressure detection range (0-150 kPa), and high sensitivity (1.28 kPa-1). 相似文献
486.
建立高效液相色谱法同时测定白花蛇舌草药材中对香豆酸和熊果酸含量的方法。采用Eclipse SB–C18色谱柱(250 mm×4.6 mm,5μm),以甲醇–0.05%甲酸梯度洗脱,流量1 m L/min,对香豆酸和熊果酸的检测波长分别为310 nm和210 nm,柱温30℃。对香豆酸和熊果酸含量分别在0.001 79~0.028 64 mg/m L和0.021 3~0.340 8 mg/m L范围内与色谱峰面积呈良好的线性关系,线性相关系数r分别为0.999 8,0.999 6。对香豆酸和熊果酸的平均加标回收率分别为98.59%,98.23%,测定结果的相对标准偏差分别为0.81%,0.94%(n=6)。样品溶液在24 h内稳定。该方法适用于白花蛇舌草药材中对香豆酸和熊果酸的含量测定。 相似文献
487.
采用高效液相色谱法(HPLC)测定麻黄细辛附子(MXF)汤复方水提液中盐酸麻黄碱、盐酸伪麻黄碱、苯甲酰新乌头原碱、苯甲酰乌头原碱、苯甲酰次乌头原碱含量,考察了4种大孔树脂(HPD–100,HPD–722,HPD–400,HPD–600型)对5种生物碱的静态吸附、解吸附性能,筛选出分离纯化麻黄细辛附子汤中生物碱的最佳树脂。结果显示,HPD–722型树脂对5种生物碱的吸附过程稳定且吸附量大,具有较高的解吸附率(87.26%),优于其它3种树脂。HPD–722型大孔树脂适用于富集麻黄细辛附子汤中的生物碱类化合物。 相似文献
488.
This paper proposes a data-driven method-based fault diagnosis method using the deep convolutional neural network (DCNN). The DCNN is used to deal with sensor and actuator faults of robot joints, such as gain error, offset error, and malfunction for both sensors and actuators, and different fault types are diagnosed using the trained neural network. In order to achieve the above goal, the fused data of sensors and actuators are used, where both types of fault are described in one formulation. Then, the deep convolutional neural network is applied to learn characteristic features from the merged data to try to find discriminative information for each kind of fault. After that, the fully connected layer does prediction work based on learned features. In order to verify the effectiveness of the proposed deep convolutional neural network model, different fault diagnosis methods including support vector machine (SVM), artificial neural network (ANN), conventional neural network (CNN) using the LeNet-5 method, and long-term memory network (LTMN) are investigated and compared with DCNN method. The results show that the DCNN fault diagnosis method can realize high fault recognition accuracy while needing less model training time. 相似文献
489.
相空间中有二阶线性单面约束的非完整系统的Lie对称性与守恒量 总被引:4,自引:0,他引:4
研究相空间中有二阶线性单面约束的非完整系统的Lie对称性与守恒量。首先根据微分方程在无限小变换下的不变性建立Lie对称性所满足的确定方程和限制方程,给出结构方程和守恒量;其次讨论系统的Lie对称性逆问题。最后举一实例说明结果的应用。 相似文献
490.
落叶松、白桦树木生长应力测试研究初探 总被引:1,自引:0,他引:1
对小兴安岭落叶松和白桦树木生长应力的实测结果进行理论分析,根据实验数据的处理,给出实测树木生长应力的分布图,其中纵向生长应力占有主要地位. 相似文献