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491.
In this article, the modified Buzzi–Ferraris model discrimination method was used to design experiments to discriminate between the terminal and penultimate models for styrene methyl methacrylate (STY/MMA) copolymerization. The measured variables were 13C-NMR peak areas. The peak area assignments of Aerdts8 were used. After nine experiments, the terminal model was picked over the penultimate model at 99.99% confidence. More importantly, the experimental data showed that computer simulated data used in previous studies were realistic, and the conclusions drawn from the simulation studies were valid. This experimental verification continues to show that the use of statistical model discrimination techniques can improve our ability to discriminate between competing copolymerization models. © 1996 John Wiley & Sons, Inc.  相似文献   
492.
493.
We investigate the discrimination of pure-mixed (quantum filtering) and mixed-mixed states and compare their optimal success probability with the one for discriminating other pairs of pure states superposed by the vectors included in the mixed states. We prove that under the equal-fidelity condition, the pure-pure state discrimination scheme is superior to the pure-mixed (mixed-mixed) one. With respect to quantum filtering, the coherence exists only in one pure state and is detrimental to the state discrimination for lower dimensional systems; while it is the opposite for the mixed-mixed case with symmetrically distributed coherence. Making an extension to infinite-dimensional systems, we find that the coherence which is detrimental to state discrimination may become helpful and vice versa.  相似文献   
494.
为快速、准确定量凉皮中多元素含量,采用微波消解法对凉皮样品进行消解处理,优化了ICP-MS仪器参数条件,选择适合的内标元素,运用动能歧视技术(KED)降低质谱干扰,利用微波消解-电感耦合等离子体质谱(ICP-MS)法测定凉皮中K、Ca、Mg、Be、V、Cr、Ni、As、Se、Mo、Ag、Cd、Sn、Pb、B、Al、Mn、Fe、Co、Cu、Ba及Hg等22种元素含量,各元素相关系数均大于0.995。通过对方法的线性范围、检出限、准确性、稳定性、加标回收率的考察。结果表明,KED-ICP-MS法测定凉皮中各元素的相对标准偏差(RSD,n=6)在0.60%~8.1%,方法加标回收率(n=6)在74.1%~120%,标准曲线线性关系良好(R2=0.995~0.999)。方法具有简便、快速、灵敏、准确的特点,适用于凉皮中多元素的高通量检测。  相似文献   
495.
The possibility of improving the discrimination capability (DC) in color pattern recognition is analyzed. In each channel, red, green and blue (R, G, B), a region of support is designed to improve the behavior of the Phase Only Filter matched to the corresponding component of the target. The procedure of optimization is based on the analytical expressions which give the DC in R, G, B channels, for real valued input scenes. Computer simulation results are presented and discussed.  相似文献   
496.
Diallyl phthalate (DAP) resin plates were irradiated with fission fragments, and then etched in aqueous solution of KOH. Etched tracks were observed and counted by using an optical microscope. The detection efficiency of fission fragments was about 100% for both perpendicular and random incidence. DAP plates were insensitive to alpha particles and fast neutrons. These characteristics are suitable for detecting selected fission fragments, which coexist with alpha particles or fast neutrons. DAP plates are valuable for quantitative analysis of fissionable materials and neutron dosimetry. DAP and allyl diglycol carbonate (CR-39) were formed into copolymers in various ratios. The copolymers showed intermediate characteristics between DAP and CR-39. The fabrication of the copolymers made it possible to control the discrimination level for detection of heavy charged particles.  相似文献   
497.
Sibasish Ghosh 《Pramana》2001,56(2-3):403-409
It is shown that the no-signaling constraint generates the symmetric as well as the asymmetric 1 → 2 optimal universal quantum cloning machine of single qubits A part of this paper has been published in Phys. Lett. A261, 17–19 (1999) in collaboration with G Kar and A Roy.  相似文献   
498.
In this paper, we study quantum teleportation of atomic states via a hybrid entangled state (HES) involving an atom and a cavity field. And we investigate how to implement controlled phase (CP) gates between atomic internal states and coherent states of cavity field. We also discuss the methods of distinguishing coherent states |±α〉in a cavity. Finally, a brief discussion about the feasibility of this scheme in experiment is presented.  相似文献   
499.
痕量动物油和植物油的区分检验研究   总被引:2,自引:0,他引:2  
采用碱催化甲酯化的前处理方法,应用气相色谱-质谱联用技术对动物油和植物油的区分检验进行了研究。实验检出了6种主要脂肪酸:肉豆蔻酸、棕榈油酸、棕榈酸、亚油酸、油酸、硬脂酸。分析了动物油与植物油在成分及相对含量上的差异,并且找出了动物油和植物油在不饱和度上的差别。根据动物油与植物油的差异点,可以对动物油和植物油进行区分。  相似文献   
500.
狭缝式高灵敏裂变中子探测系统   总被引:9,自引:0,他引:9       下载免费PDF全文
研制了狭缝-外延式高灵敏大面积PIN裂变中子探测系统. 其对14MeV,2.5MeV中子灵敏度可达10-16C·cm2,比原有典型的脉冲裂变中子探测系统高4个量级. 采用外延式铅狭缝准直结构,研制灵敏区尺寸为60mm,厚度为200μm—300μm的大面积PIN半导体探测器、以Be膜为衬底,有效直径为60的235U裂变靶,解决了该探测器研制中的高灵敏度和n/γ分辨难题. 该系统已在实践中获得成功应用. 关键词: 裂变中子探测系统 大面积PIN探测器 大面积裂变靶 高灵敏探测系统  相似文献   
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