Integrated missile guidance and control using optimization-based predictive control

Nonlinear Dynamics - This paper focuses on the design and implementation of optimization-based predictive control for the problem of missile interception. Due to the inherent nonlinearities of the...     

Dynamic Variation of Amino Acid Contents and Identification of Sterols in Xinyang Mao Jian Green Tea

As important biomolecules in Camellia sinensis L., amino acids (AAs) are considered to contribute to the overall green tea sensory quality and undergo dynamic changes during growth. However, limited by analytical capacity, detailed AAs composition in different growth stages remains unclear. To address this question, we analyzed the dynamic changes of 23 AAs during leaf growth in Xinyang Mao Jian (XYMJ) green tea. Using amino acid analyzer, we demonstrated that most AAs are abundant on Pure Brightness Day and Grain Rain Day. After Grain Rain, 23 AAs decreased significantly. Further analysis shows that theanine has a high level on the day before Spring Equinox and Grain Rain, accounting for 44–61% of the total free AAs content in tea leaves. Glu, Pro, and Asp are the second most abundant AAs. Additionally, spinasterol and 22,23-dihydrospinasterol are first purified and identified in ethanol extract of XYMJ by silica gel column chromatography method. This study reveals the relationship between plucking days and the dynamic changes of AAs during the growth stage and proves the rationality of the traditional plucking days of XYMJ green tea.     

A Regularization Homotopy Strategy for the Constrained Parameter Inversion of Partial Differential Equations

The main difficulty posed by the parameter inversion of partial differential equations lies in the presence of numerous local minima in the cost function. Inversion fails to converge to the global minimum point unless the initial estimate is close to the exact solution. Constraints can improve the convergence of the method, but ordinary iterative methods will still become trapped in local minima if the initial guess is far away from the exact solution. In order to overcome this drawback fully, this paper designs a homotopy strategy that makes natural use of constraints. Furthermore, due to the ill-posedness of inverse problem, the standard Tikhonov regularization is incorporated. The efficiency of the method is illustrated by solving the coefficient inversion of the saturation equation in the two-phase porous media.     

铁、锰和硼元素对厌氧微生物脱氮除磷的影响

为研究在废水处理系统中铁、锰和硼元素对厌氧微生物生长代谢的影响,采用厌氧血清瓶培养实验,确定了在不同铁、锰和硼元素的投加量下,此种厌氧微生物脱氮除磷能力的变化。结果表明,铁元素的投加量为30mg·L^-1时,除磷效果最好;锰元素的投加量不应该超过2．5mg·L^-1;而硼元素对除磷无促进作用。     

NaYbF4纳米晶浓度调节方法研究

本文采用热分解法制备了NaYbF₄纳米晶.通过TEM图像对NaYbF₄纳米晶的尺寸进行表征.根据Beer-Lambert理论建立了NaYbF₄纳米晶浓度与其光吸收度间的关系.提出了NaYbF₄纳米晶浓度调节方法,利用NaYbF₄纳米晶中Yb³⁺的吸收光谱确定溶液中NaYbF₄纳米晶的浓度,并给出了纳米晶浓度调节公式.为了检验这种浓度调节方法,对五批次NaYbF₄纳米晶样品的浓度进行调节,发现浓度调节方法非常可靠.并对调整后的浓度进行多次测量,检验此调节方法的误差,最大误差在9;.     

中心性浆液性脉络膜视网膜病变者全血14种微量元素含量测定

用ＩＣＰ－ＡＥＳ法对中心性浆液性脉络膜机网膜病变１２例，对照健康人组１３例全血微量元素测定，发现有一些微量元素明显升高或降低，其中铬（Ｃｒ）较健康人组升高（Ｐ＜０．０５），锰（Ｍｎ）较健康人组高（Ｐ＜０．０５），均有显著性差异；钛（Ｔｉ）较健康人组降低（Ｐ＜０．００２５）．进一步研究可能对中心性浆液性脉络膜视网膜病变的发病原因、治疗等提供新的见解和有用的治疗方法．     

Atomically Dispersed Cobalt/Copper Dual-Metal Catalysts for Synergistically Boosting Hydrogen Generation from Formic Acid

The development of practical materials for (de)hydrogenation reactions is a prerequisite for the launch of a sustainable hydrogen economy. Herein, we present the design and construction of an atomically dispersed dual-metal site Co/Cu−N−C catalyst allowing significantly improved dehydrogenation of formic acid, which is available from carbon dioxide and green hydrogen. The active catalyst centers consist of specific CoCuN₆ moieties with double-N-bridged adjacent metal-N₄ clusters decorated on a nitrogen-doped carbon support. At optimal conditions the dehydrogenation performance of the nanostructured material (mass activity 77.7 L ⋅ g_metal⁻¹ ⋅ h⁻¹) is up to 40 times higher compared to commercial 5 % Pd/C. In situ spectroscopic and kinetic isotope effect experiments indicate that Co/Cu−N−C promoted formic acid dehydrogenation follows the so-called formate pathway with the C−H dissociation of HCOO* as the rate-determining step. Theoretical calculations reveal that Cu in the CoCuN₆ moiety synergistically contributes to the adsorption of intermediate HCOO* and raises the d-band center of Co to favor HCOO* activation and thereby lower the reaction energy barrier.