排序方式: 共有19条查询结果,搜索用时 15 毫秒
1.
基于芘的荧光熄灭的单质碘荧光敏感膜的研究 总被引:8,自引:0,他引:8
单质碘熄灭固定于增塑的PVC膜中的芘的荧光,且这种熄灭作用可逆。本据此研制了用于测定单质碘浓度的荧光敏感膜,最佳膜组成为2~4mg芘、50mgPVC粉、100mg邻苯二甲酸二异辛酯,测定碘的浓度范围为2.26×10^-5~1.04×10^-3mol/L。此膜测定单质碘的重现性好,响应时间小于40s。除Fe^3+、Bi^3+外,其它常见离子均无干扰。将此膜用于食盐中碘的测定,结果令人满意。 相似文献
2.
This paper observes the parametric excitation on atom chip by measuring the trap loss when applying a parametric modulation. By modulating the current in chip wires, it modulates not only the trap frequency but also the trap position. It shows that the strongest resonance occurs when the modulation frequency equals to the trap frequency. The resonance amplitude increases exponentially with modulation depth. Because the Z-trap is an anharmonic trap, there exists energy selective excitation which would cause parametric cooling. We confirm this effect by observing the temperature of atom cloud dropping. 相似文献
3.
Guiding Neutral Atoms with Two Current-Carrying Wires and a Vertical Bias Field on the Atom Chip 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《中国物理快报》网站下载免费的PDF全文](/ch/ext_images/free.gif)
We demonstrate the guiding of neutral atoms with two parallel microfabricated current-carrying wires on the atom chip and a vertical magnetic bias field. The atoms are guided along a magnetic field minimum parallel to the current-carrying wires and confined in the other two directions. We describe in detail how the precooled atoms are efficiently loaded into the two-wire guide. We present a detailed experimental study of the motional properties of the atoms in the guide and the relationship between the location of the guide and the vertical bias field. This two-wire guide with vertical bias field can be used to realize large area atom interferometer. 相似文献
4.
将锂离子选择性中性载体和亲脂性pH指示剂结合在增塑的PVC膜中,pH缓冲液中锂离子浓度的变化将引起膜颜色的改变.将该膜涂覆在光电二极管光敏区并与发出锐线光的发光二极管组装在一起,构成了一种新型锂离子选择性传感装置.报道了这一传感装置的响应特性,探讨了临床分析应用的可能性. 相似文献
5.
Eigenface method used in face recognition is introduced to reduce the pattern of interference fringes appearing in the absorption image of cold rubidium atom cloud trapped by an atom chip. The standard method for processing the absorption image is proposed, and the origin of the interference fringes is analyzed. Compared with the standard processing method which uses only one reference image, we take advantage of fifty reference images and reconstruct a new reference image which is more similar to the absorption image than all of the fifty original reference images. Then obvious reduction of interference fringes can be obtained. 相似文献
6.
7.
Microwave coherent manipulation of cold atoms in optically induced fictitious magnetic traps on an atom chip
下载免费PDF全文
![点击此处可从《中国物理 B》网站下载免费的PDF全文](/ch/ext_images/free.gif)
We propose a novel on-chip platform for controlling and manipulating cold atoms precisely and coherently. The scheme is achieved by producing optically induced fictitious magnetic traps(OFMTs) with 790 nm(for ~(87)Rb) circularly polarized laser beams and state-dependent potentials simultaneously for two internal atomic states with microwave coplanar waveguides. We carry out numerical calculations and simulations for controlled collisional interactions between OFMTs and addressable single atoms' manipulation on our designed hybrid atom chips. The results show that our proposed platform is feasible and flexible, which has wide applications including collisional dynamics investigation, entanglement generation,and scalable quantum gates implementation. 相似文献
8.
本文描述了一种新的测量二氧化硫的荧光型光纤传感器。溶于内充液的奎宁被用作敏感物,通过气透膜将内充液与水溶液分开。传感器对二氧化硫的响应范围是3×10~(-6)~3×10~(-4)mol/L。报道了传感器的重现性、稳定性、响应时间和选择性。用该传感器测定了含二氧化硫的实际样品并与碘量法进行了比较。 相似文献
9.
The effects of surface-induced evaporative cooling on an atom chip
are investigated. The evolutions of temperature, number and
phase-space density of the atom cloud are measured when the atom
cloud is brought close to the surface. Rapid decrease of the
temperature and number of the atoms is found when the atom-surface
distance is < 100~μm. A gain of about a factor of five on the
phase-space density is obtained. It is found that the efficiency
of the surface-induced evaporative cooling depends on the
atom-surface distance and the shape of the evaporative trap. When
the atoms are moved very close to the surface, severe heating is
observed, which dominates when the holding time is >8~ms. It is
important that the surface-induced evaporative cooling offers novel
possibilities for the realization of a continuous condensation,
where a spatially varying evaporative cooling is required. 相似文献
10.
<正>We propose a wire configuration to create a one-dimensional(1D) array of magnetic microtraps for trapping ultracold atoms.The configuration is formed by replacing the central part of the Z-wire pattern with a zigzag wire. We simulate the performance of this pattern by the finite element method which can take both the width and depth of the wire into consideration.The result of simulation shows that this configuration can create magnetic microtraps which can be separated and combined by changing the bias magnetic field.We manage to split the Z-wire trap and prove that a similar result can occur for the new wire configuration.The fabrication processes of the atom chip are also introduced.Finally we discuss the loading method. 相似文献