A quadrature method for a class of strongly oscillatory infinite integrals

A constructive process is presented which leads to a class of quadrature formulas with any preassigned compound precision for the numerical integration of rapidly oscillating functions on (0, ) of the forme ^–x F(x, x), where is a large parameter andF(·,y) is periodic of period unity iny.1980 Mathematics Subject Classification, Primary 41A55, Scondary 41A60     

Multivariate interpolation in odd-dimensional euclidean spaces using multiquadrics

Let or . Givenf: ⁿ , we establish convergence orders of interpolation where the cardinal functionx withx(j)=_0j is a linear combination of integer shifts, of a fast decaying function

Strategies for compound identification and quantification using fused silica capillary column GC/MS

A test mixture containing 28 compounds plus their stable isotopically labeled analogs was analyzed on a daily basis for one month during a series of routine fused silica capillary column GC/MS analyses in order to establish the precision with which retention times and responses were produced. These long-term precision data were evaluated to determine how to best predict retention times and how to best reproduce quantification. Results clearly indicate that relative retention times should be calculated using the reference compound eluted most closely to the target compound and that quantification should be based on relative response using a chemically “similar” compound.     

Chemical processes in a plasma centrifuge

Investigations on separating hydrogen isotopes have been carried out in a system with plasma rotating in crossed E × B fields— a plasma centrifuge. The processing of chemical reactions in the plasma phase in a strong centrifugal field was simulated. High radial separation factors (up to 140) have been obtained for the decomposition of water vapor with simultaneous separation of hydrogen and oxygen. Because of spatial separation of the dissociation products there was no need for their special quenching.     

The new approach of standardization of capillary electrophoresis

In this paper, we develope the new standardization methods to eliminate the influence in capillary electrophoresis (CE). The markers were used to determine the basis position and then correct the data of sample by the migration time of standard sample, and make the migration time of samples consistent with the standard sample by the criterion of the marker. The problem of time transition was corrected in this way. Then according to the peak height or peak area of the marker in the sample (peak height was used here) compared with the standard sample, the sample data was zoomed appropriately. The absorbance error was made to be correct. The wavelet de-noise method was also used to make the data smooth and get a good baseline.     

体积流量法配制多组分气体混合物

建立了一种简便、价廉的多组分气体混合物的动态制备方法并设计和组装了动态体积配气仪。用气相色谱对动态体积配气仪配制的混合气体进行分析并与其理论配比相对照，结果表明，该方法的准确性、稳定性和重复性是令人满意的。此外，按照配气的过程对影响配气精度的因素进行了理论分析。分析表明，气流流速的稳定性、流速测定的准确性和气路条件的一致性是决定配气效果的主要因素。     

Precision of an automated all-glass capillary gas chromatography system with an electron capture detector for the trace analysis of estrogens

Subnanogram detection of steroids has become increasingly important today. One applicable method for gas chromatographic determination of subnanogram quantities of estrogens as halogenated derivatives is electron capture detection. HFB-derivatives of 7 different estrogens were automatically injected onto a prolonged narrow bore wall-coated glass capillary column. Normal split injection could not be used for this trace analysis because of too much loss of sample. Only small amounts of sample were available from which double analysis had to be performed. Cross-contamination of the automatic sampling system as well as precision of retention times and peak areas were determined. The type of injection described showed better quantitative results compared to the splitless injection technique. All details of the system used together with the results are this discussed in this paper.     

靛酚兰法对氨渗透管渗透率的测定

研究了对氨渗透管渗透率测定的靛酚兰法。该方法具有简单、灵敏、准确、重复和操作方便等优点。     

Beating Standard Quantum Limit with Weak Measurement

Weak measurements have been under intensive investigation in both experiment and theory. Numerous experiments have indicated that the amplified meter shift is produced by the post-selection, yielding an improved precision compared to conventional methods. However, this amplification effect comes at the cost of a reduced rate of acquiring data, which leads to an increasing uncertainty to determine the level of meter shift. From this point of view, a number of theoretical works have suggested that weak measurements cannot improve the precision, or even damage the metrology information due to the post-selection. In this review, we give a comprehensive analysis of the weak measurements to justify their positive effect on prompting measurement precision. As a further step, we introduce two modified weak measurement protocols to boost the precision beyond the standard quantum limit. Compared to previous works beating the standard quantum limit, these protocols are free of using entangled or squeezed states. The achieved precision outperforms that of the conventional method by two orders of magnitude and attains a practical Heisenberg scaling up to n=106 photons.     

两种多天线GNSS定姿方法的精度分析

基于高精度多天线GNSS基线分量及精度估计结果,实现了两种常用的多天线定姿方法:直接姿态法和最小二乘姿态法。利用一套车载三天线GNSS实测数据和高精度惯性导航系统(陀螺漂移0.005(°)/h,加速度计零偏优于10~(-3)g)输出的姿态结果,深入分析了两种定姿方法的内、外符合精度。实验结果表明:两种定姿所解算的航向角、俯仰角和横滚角的精度分别为:直接法的内符合精度约为0.3°~0.5°、0.3°~1.0°、0.5°~1.0°,最小二乘法约为0.1°、0.2°~0.5°、0.5°~2.0°,即最小二乘法对航向角估计有明显改善,对俯仰角和横滚角改善不明显;两种方法的姿态外符合精度(消除航向系统偏差)基本一致,约为0.08°、0.15°、0.42°,但是最小二乘法得到的航向角系统偏差更小。