一阶导数

The artificial neural network models of original spectrum and two pretreated spectra (firstderivative and standard normal variate, respectively) of osthol and imperatorin were established.

分别利用萃取物的原始光谱和两种预处理光谱建立了网络的数学校正模型，并把所得结果进行了比较，确定用一阶导数光谱所建立的模型为最佳网络模型。

Objective: To establish a simple rapid method for determining Kjeldahl nitrogen content by 1st order differential coefficient single sweep polarography.

建立用一阶导数单扫描极谱法测定食品中凯氏氮含量的简单、快速的方法。

However, the pseudo-triaxial strengths of several rocks from the best fitting solutions have great scatterness from the real magnitudes. Also, it does not correspond to the experimental results that rock has the same strength under conventional triaxial compression and tension; the maximum increase of strength from intermediate principal stress has a linear relation with the minor principal stress; and the first-order derivative of strength has an interruption at the peak point.

此外，统一强度理论认为岩石三轴伸长强度与常规三轴压缩强度相同，在最小主应力恒定时中间主应力引起的强度最大增加值随最小主应力线性增加，且强度关于中间主应力的一阶导数在峰值点是不连续的，这些都与试验结果不能完全协调。

To obtain more accurate variation range of the structural response, the first-order derivatives in the Taylor series expansion of the structural response are also considered to be interval.

将结构响应Taylor展开式中的一阶导数也看成区间的，可得到框架结构响应更加准确的变化范围。

Padé approximation is an effective rational approximation.Using the first derivative of Gaussian function as basic wavelet,Pad conversion is used to obtain its rational fraction approximation.

采用高斯函数一阶导数作为基本小波，用Padé变换获得其有理分式逼近，利用开关电流技术实现小波滤波器可获得小波变换所需的基本小波及其膨胀小波。

In view of the non-linear relation between the hefts of the partial stress tensor and the velocity gradient of the fluid, the intrinsic equation only depends on the first order differential coefficient of the velocity gradient.

考虑流体的偏应力张量分量与速度梯度为非线性关系的情况，本构方程仅依赖于速度梯度的一阶导数。

The powder pharmaceutical samples of sulfaguanidine are analyzed nondestructive by conventional and first derivative near-infrared diffuse reflectance spectra.

用常规和一阶导数近红外漫反射光谱法非破坏分析了粉末药品磺胺脒。

The results showed that both the break point on the Ia-c curve and the minimum of the derivative variation corresponding to the λa-c curve agreed very well with the critical micelle concentration of the surfactant in aqueous solution as measured by surface tension technique.

以对二甲氨基苯甲腈为探针，测定它在表面活性剂(C12TABr、SDS、C12E23、C12-3-12·2Br)水溶液中的第二重荧光强度和对应的特征波长对表面活性剂浓度曲线，由Ia-c 曲线的转折点或λa-c曲线对应的一阶导数极小点可以获得临界胶团浓度。

First derivative spectrophotometric method for determining of micro samarium in electroplating solution is given,using xylenol orange as color reagent.

提出了利用二甲酚橙为显色剂测定电镀液中微量钞的一阶导数分光光度法。

In 1999, Struijk found that the myelinated nerve could be excited by transverse field induced by pulsed magnetic stimulation without the effect of tissue unhomogeneities and bends in the nerves.

因此，在近几年的神经磁刺激研究中，也局限于讨论感应电场纵向分量的作用，以纵向场负的一阶导数极大值作为刺激方式的选取及线圈改进的衡量标准。

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。