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The oily substances and the acidic components were characterized using elementary analysis, IR spectral analyses and acidimetry.

采用石油醚和三氯甲烷分级萃取孤岛油田含聚污水中的油分，得到两个不同极性的组分F1和F2；用碱抽提法从酸值较高的F2组分中分离酸性物质并将其甲酯化，通过柱层析法将甲酯化物分成Ⅰ、Ⅱ和Ⅲ三个甲酯组分。

Alternatively, the spectral softening above 2 GeV could be due to gamma-ray absorption via photon-photon pair production on the soft X-ray photon field of the host active galactic nucleus, but such an interpretation would require the dissipation region to be located very close (l~100 gravitational radii) to the black hole, which would be inconsistent with the X-ray spectrum of the source.

另外的关于2 GeV以上能谱变软的可能解释是高能光子和寄主活动星系核的软X射线辐射场通过电子对产生反应而被吸收，但是这个解释要求反应区域要很靠近中心黑洞(1~100倍引力半径)，这和3C 454.3的X射线测量谱相矛盾。

At the same time, for the process additive and multiplicative uncertainties mostly encountered in practice, the sufficient and necessary conditions for holding the control system robust stability are analyzed, and thus, an intuitive determination method is provided based on the spectral radius criterion.

同时，对于实际中最常见的被控过程的加性和乘性不确定性，分析了控制系统保证鲁棒稳定性的充要条件，由此给出了基于谱半径判据的直观判定方法。

The spectral graph theory is one of the main branches in algebraic graph theory, it is mainly concerned with the adjacency spectrum and the Laplacian spectrum.

图的谱理论是代数图论中的一个重要课题，主要涉及图的邻接谱与图的Laplacian谱的研究。

A novel direction of arrival and polarization estimation of electromagnetic vector sensors mounted on the airframe is proposed based on biquaternion. The signal processing model for EM-sensor mounted on the airframe is made by biquaternion and then the eigenvalue decomposition of spectral matrix is obtained by means of the EVD of its quaternion adjoint matrix. The memory requirement for data is reduced, and more accurate estimation result is gotten by deducing the stronger orthogonality constraint between the sin- gal and noise subspaces on the field of biquaternion. The performance of the new algorithm is confirmed through numerical examples.

针对机载电磁矢量传感器阵列DOA和极化参数估计问题，提出了一种基于复四元数估计方法，该算法利用四元数建立机载电磁矢量传感器阵列信号处理模型，然后利用四元数联合矩阵的特征分解得到阵列数据相关矩阵的特征分解，一方面使得计算过程中数据的贮存量大大减少，另一方面通过推导得到信号子空间和噪声子空间在四元数域上的正交性从而使DOA和极化参数佑计的精度更高，仿真证实了本算法的有效性。

Spectral methods and the classical Crank-Nicolson scheme are applied to deduce the full discrete system for the continuous model, then the variational adjoint assimilation approach is used to derive the gradient and the corresponding adjoint system.

从这个全离散问题出发，结合全局或局部已知的观测数据，分别构造梯度下降算法求解相应的最优化问题。我们分析了采用不同方法计算梯度所需的代价，另外，还给出一种选择最优迭代步长的算法。

As important ways for numerical solutions of partial differential equations, spectral methods have been developed rapidly in the past several decades. They not only have been widely applied to numerical simulations in various fields such as physics, mechanics, aerology, oceanics etc, and their theories of numerical analysis also tend to perfect.

作为数值求解的一种手段，谱方法在近几十年得到了蓬勃的发展，它不仅被广泛运用于物理、力学、大气、海洋等领域的数值计算，而且它的数值分析理论也不断地趋于完善。

We find serval conditions that are equivalent to 2-tournament matrices being singular,give the bound for the maximum algebraic multiplicity of 0 as an eigenvaulle of n order2-tournament,obtion the spectral radius of a singular 2-tournament matrix of order nis bounded above by n-2,and investigate 2-tournament matrix achieving this bound.

第五章讨论了2-竞赛矩阵的奇异性和特征值之间的关系，得到了2-竞赛矩阵奇异的充要条件，给出了2-竞赛矩阵的零化向量的刻划，得到了得分向量，3-圈数目与奇异性的关系；给出了2-竞赛矩阵的特征值0的代数重数的上下界，得到了奇异的2-竞赛矩阵谱根的最大值及谱根达到最大值的竞赛矩阵的得分向量的特征。

Diamond, an allotrope of carbon, has many physicochemical properties unrivaled by other known materials, such as superhardness, high thermal conductivity, high spectral transmittance and perfect electrical insulation. Thus it is considered an ideal material for many special applications in mechanics, thermotics, optics, electronics and other fields.

金刚石是碳的一种同素异形体，具有许多其它材料无法比拟的物理化学性质，如超高硬度、高导热率、高光学透过率和极好电绝缘性，因而在力学、热学、光学和电子等领域有许多特殊的应用价值。

Immediately after admission, the 290 nm band has disappeared and evolution of bands in the range of the di-, tri-~nd tetraenylic ions proceeds, resulting in the same final spectral pattern as when starting from allyl alcohol.

入院后立即，在290纳米带已经消失和演化的乐队在二叔，三范围届tetraenylic离子的收益，在同样的最终结果光谱格局从丙醇时开始。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。