四元

Here goes lumber from the Maine woods, which did not go out to sea in the last freshet,risen four dollars on the thousand because of what did go out or was split up; pine, spruce, cedar —— first, second, third, and fourth qualities, so lately all of one quality, to wave over the bear, and moose, and caribou.

经过这里的是缅因森林中的木料，上次水涨时没有扎排到海里去，因为运出去或者锯开的那些木料的关系，每一千根涨了四元，洋松啊，针枞啊，杉木啊，——头等，二等，三等，四等，不久前还是同一个质量的林木，摇曳在熊、麋鹿和驯鹿之上。

By comparing traditional circular-shape with cross-shape, arrow-shape, floriated-shape and gammadion-shape electrodes, we found that the electrode shape has an important effect on the output efficiency of light, and the light extraction efficiency of gammadion electrode is the highest.

曾祥华 扬州大学物理科学与技术学院，扬州 225002利用有限元法模拟研究四元AlGaInP LED电极形状对电流扩展层GaP中电流分布的影响，通过优化电极形状获得较为均匀分布的电流，以此提高芯片的出光效率和提升产品品质。

Three dimensional rotation represented by quaternion has two advantages over that by matrix: first, the geometric meaning is definitude; second, computation is easy.

用四元数表达三维的旋转与使用矩阵相比具有两个优点：第一，几何意义明确；第二，计算简单。

Quaternions do not suffer from gimbal lock, because they do not express rotations relative to three separate axes.

四元数就不会遭受万向节锁的痛苦，因为它不用三个分离的轴表示旋转。

And find that each element in the group can be decomposed into the product of two quaternion component matrices.

指出SO(4)群中每个矩阵都可以分解为两种单位四元数分量矩阵乘积的形式。

Based on a brief review on developments of number system, a new developed pattern is proposed. The quaternion is extended to a matrix form aI+bA+cB+dC, in which the identity matrix I and three special matrices A, B, C correspond to number 1 and three units of imaginary number i, j, k, respectively.

在数系发展的基础上，提出了一种新的发展模式：四元数推广为矩阵形式aI+bA+cB+dC，其中单位矩阵I和3个特殊矩阵A，B，C分别相应于数1和虚数单位i，j，k。

Zeros of irreducible real quaternionic polynomial are the isolated point solutions of the original polynomial equation.

不可约四元数多项式的零点对应原多项式的孤立点解，一次实系数多项式的零点对应原多项式的实数解，二次实系数多项式(Δ＜0)的零点对应原多项式的等价类解。

To understand the molecular basis of the high selectivity of the inhibitor and the mechanism of feedback inhibition, we determined the crystal structure of LiCMSC (C-terminal regulatory domain of LiCMS) in complex with isoleucine, and performed a biochemical study of the inhibition of LiCMS using mutagenesis and kinetic methods.

丁建平和赵国屏课题组合作，运用结构生物学和生物化学的方法分别研究了 CMS 的催化结构域与其底物丙酮酸、乙酰辅酶 A 、金属辅基的四元复合物的晶体结构，和 CMS 的调节结构域与反馈抑制剂异亮氨酸的复合物的晶体结构，以及全酶与这些配体相互结合的动力学性质。

Isopiestic measurements have been carried out at 298.15K for the quaternary aqueous solution H2O+KCl+NaCl+NH4Cl saturated with potassium chloride and its ternary sub-systems H2O+KCl+NaCl and H2O+KCl+NH4Cl.

在298.15K条件下采用等压实验方法对KCl饱和的四元水溶液体系H2O+KCl+NaCl+NH4Cl及其两个三元亚系H2O+KCl+NaCl和H2O+KCl+NH4Cl进行了研究。

We know that examples of special Lagrangian submanifolds are very important for studying these submanifolds.

我们也采取相应的思想，得到一些四元数欧式空间中有关极小拉格朗日的伯恩斯坦型定理。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。