1)  bispectral analysis
二阶谱分析
2)  second order
二阶
1.
The existence of periodic solutions for a class of second order functional differential equations;
一类二阶泛函微分方程周期解的存在性
2.
Interval oscillation for second order neutral functional differential equations;
一类二阶中立型泛函微分方程的区间振动性
3.
Oscillation comparison theorems of solutions for second order nonlinear elliptic differential equations;
二阶非线性椭圆型微分方程解的振动比较定理
3)  second-order
二阶
1.
Oscillation criteria for a kind of second-order nonlinear difference equation;
一类二阶非线性差分方程的振动准则
2.
Boundedness of second-order nonlinear functional differential equations;
关于二阶非线性泛函微分方程的有界性
3.
A Second-order Algorithm for the Numerical S imulation of Stochastic Resonance;
一种用于随机共振数值模拟的二阶方法
4)  two-stage sampling
二阶抽样
1.
Extension of two useful results in two-stage sampling and its applications;
对二阶抽样中两个定理的扩充及其应用
2.
Based on the calculations in simple random sampling,stratified random sampling and two-stage sampling,it is shown that when the sampling size of two-stage sampling is 1/2 that of simple random sampling,the mean square error is much smaller than that of simple random sampling.
在通过对简单随机抽样、分层随机抽样和二阶抽样的实例计算之后,证明二阶抽样在抽样样本量为简单随机抽样的1/2时,其样本方差远小于简单随机抽样的样本方差;在样本量与分层随机抽样相同的情况下,其样本方差也要远小于分层随机抽样方差,提高了抽样数据的可信度和精度,从而肯定了二阶抽样方法对于数控机床可靠性研究中数据抽样问题的适用性,节约了抽样成本。
3.
Based on the precision and the cost of the relationship between the use of conditional extremum for the function of several variables method to determine when the first sample for sampling with probability proportion to size,the second-simple random sampling,the two-stage sampling is optimal allocation.
本文根据精度与费用之间的关系,利用求多元函数条件极值的方法,确定当第一级抽样为有放回PPS抽样,第二级抽样为简单随机抽样时,二阶抽样的样本容量最优分配。
5)  second-order fluid
二阶流体
1.
Flow rate distribution of the non-steady flow of second-order fluid in eccentric annulus with the inner cylinder reciprocating axially;
二阶流体在内管做轴向往复运动的偏心环空中非定常流的流量分布
2.
Analytical solution to relatively moving resistance of two spheres with interstitial second-order fluid;
存在填隙二阶流体时两圆球相对运动阻力的解析解
3.
The normal viscous force of squeeze flow between two arbitrary rigid spheres with an interstitial second-order fluid was studied for modeling wet granular materials using the discrete element method.
 为了进行湿颗粒群的离散元模拟,研究两圆球颗粒间二阶流体在挤压流动时的法向粘性力· 首先用小参数法对两平行圆盘间二阶流体挤压流动的速度场和正应力分布进行了近似分析,然后用类似的方法,分析任意两圆球间二阶流体的挤压流动,得到了压力分布和法向粘性力的解析解·
6)  Second-order calibration
二阶校正
1.
Determination of salicylate acid in plasma using three-dimensional fluorescence coupled with second-order calibration algorithms;
二阶校正法与三维荧光光谱相结合直接测定人体血浆中的水杨酸
2.
In this study, TYR and TRY in amino acid oral liquid were resolved simultaneously and determined directly by using second-order calibration based on alternating trilinear decomposition algorithm and excitation-emission matrix spectrofluorimetry(EEMs), and the results were validated by standard additio.
本研究将交替三线性分解二阶校正算法与激发发射矩阵荧光法相结合,对氨基酸口服液中共存的酪氨酸和色氨酸进行了同时分辨和直接定量测定,并用加入标准法对结果进行验证,TYR和TRY的回收率分别为(96。
3.
A novel method was proposed for the rapid determination of Daunomycin Hydrochloride(DM)in plasma and urine by combining the excitation-emission fluorescence spectra with the second-order calibration based on the alternating trilinear decomposition algorithm.
文章采用三维激发发射荧光光谱与化学计量学交替三线性分解(ATLD)二阶校正法相结合,对血浆液和尿液中柔红霉素(DM)进行定量测定。
参考词条
补充资料:二次离子质谱分析


二次离子质谱分析
secondary ion mass spectrometry

二次离子质谱分析seeondaryi。n massspectrometry用质谱分析研究一次离子束轰击固体表面时溅射出来的二次离子,从而获得固体表面组成信息的方法。它能以很高的灵敏度(ppm至ppb级)对固体材料进行表面微区分析、深度分析、块体分析及图象分析,其范围包括从氢到铀的各种元素和同位素,目前深度分辨率已达30埃,成象的横向分辨率可达300埃。 二次离子发射机制是二次离子质谱的物理基础,目前有以下几种机理:①局部热力学平衡机制(LTE)。C.A.安德森和J.R.欣索恩认为,当一次离子轰击固体表面时,溅射区形成一层密集等离子体,其中的离子、电子、原子及分子之间处于局部热平衡状态,它们的平衡浓度可用萨哈方程来预言。②动力学模型。P.乔伊斯和R.卡斯坦等认为,固体表面发出的粒子呈中性准稳态,在表面附近这些粒子发生再激发而形成二次离子,并伴随俄歇电子发射。③键断模型。当一次离子束轰击化合物表面时,化合键断裂而形成原子(或分子)离子。④量子力学模型。J.M.施罗尔假设溅射原子以中性非激发状态离开表面,然后由于原子的价电子发生量子力学跃迁,过渡到金属导带顶层而引起电离。 二次离子质谱仪器可分为两类:①能显示离子图象的离子质谱仪,如离子探针;②不显象,有大束二次离子质谱仪。(陈廉)
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