HL-2A装置中性束发射光谱 诊断系统的研制与测试

在HL-2A装置上完成了一套32通道束发射诊断系统(BES)，可对径向r=12~44cm, 极向-7.5~+7.5cm二维空间范围内的长波长()电子密度扰动信息进行测量，其时间分辨率达到0.5ms，空间分辨率1~2cm。系统由内置于真空室的非对称镜头组、传输光纤、高性能探测器模块以及辅助的冷却和真空设备构成。系统的噪声在低频时(f<100kHz)主要由散粒噪声贡献，在较高频率时由散粒噪声和e噪声共同决定。在典型的HL-2A装置放电模式中，对于200kHz以下的扰动，该系统的信噪比(SNR)均大于3。     

Enhanced-performance relative humidity sensor based on MOF-801 photonic crystals

We proposed an enhanced-performance relative humidity (%RH) nano-sensor based on MOF-801/TiO₂ one-dimensional photonic crystals (1DPC). The maximum reflectance-peak wavelength of it shifted obviously in the range of 20%-90% under varying %RH levels, due to the highly moisture-sensitive MOF-801 film in the 1DPC structure. It was demonstrated that the linear spectrum sensitivity of the MOF-801/TiO₂ %RH 1DPC sensor is exceeding 119 pm/%RH from 20%RH to 90% RH, and the sensitivity of reflection power variations exhibits 1.34 dB/%RH with the resolvable relative humidity variation less than 0.1%RH at 15°C. Meanwhile, the sensor shows a fast optical response time less than 100 ms with exceptional repeatability and reliability, which promises successful measurements of human respiration. Moreover, the sensor performance on the structure of 1DPC is investigated, representing a tradeoff between the sensing sensitivity and response time.     

Enhancing teleportation fidelity by means of weak measurements or reversal

The enhancement of teleportation fidelity by weak measurement or quantum measurement reversal is investigated. One qubit of a maximally entangled state undergoes the amplitude damping, and the subsequent application of weak measurement or quantum measurement reversal could improve the teleportation fidelity beyond the classical region. The improvement could not be attributed to the increasing of entanglement, quantum discord, classical correlation or total correlation. We declare that it should be owed to the probabilistic nature of the method.     

Entropic uncertainty relation of a qubit-qutrit Heisenberg spin model and its steering

We investigate the quantum-memory-assisted entropic uncertainty relation (QMA-EUR) in a Heisenberg XYZ mixed-spin (1/2, 1) model. Coupling strength, Dzyaloshinskii-Moriya (DM) interaction and inhomogeneous magnetic field, respectively, contributing to QMA-EUR by a thermal entanglement in the hybrid-spin model are studied in detail. Furthermore, we compare the uncertainty of the bipartite hybrid model with those of qubit-qubit and qutrit-qutrit systems. Meanwhile, the effects of local PT-symmetric operation and weak measurement on the steering of entropic uncertainty are analyzed. We find that the local PT-symmetric operation can reduce the entropic uncertainty, and the entropic uncertainty can also be decreased by weak measurement reversal.     

Measurement of preferences with self-explicated approaches: A classification and merge of trade-off- and non-trade-off-based evaluation types

Self-explicated approaches are popular preference measurement approaches for products with many attributes. This article classifies previous self-explicated approaches according to their evaluation types, i.e. trade-off- versus non-trade-off-based, and outlines their advantages and disadvantages. In addition, it proposes a new method, the presorted adaptive self-explicated approach that is based on Netzer and Srinivasan’s (2011) adaptive self-explicated approach and that combines trade-off- and non-trade-off-based evaluation types. Two empirical studies compare this new method with the most popular existing self-explicated approaches, including the adaptive self-explicated approach and paired comparison preference measurement. The new method overcomes the insufficient discrimination between importance weights, as usually found in non-trade-off-based evaluation types; discourages respondents’ simplification strategies, as are frequently encountered in trade-off evaluation types; is easy to implement; and yields high predictive validity compared with other popular self-explicated approaches.     

Tutorial review on validation of liquid chromatography–mass spectrometry methods: Part II

This is the part II of a tutorial review intending to give an overview of the state of the art of method validation in liquid chromatography mass spectrometry (LC–MS) and discuss specific issues that arise with MS (and MS–MS) detection in LC (as opposed to the “conventional” detectors). The Part II starts with briefly introducing the main quantitation methods and then addresses the performance related to quantification: linearity of signal, sensitivity, precision, trueness, accuracy, stability and measurement uncertainty. The last section is devoted to practical considerations in validation. With every performance characteristic its essence and terminology are addressed, the current status of treating it is reviewed and recommendations are given, how to handle it, specifically in the case of LC–MS methods.     

A micrometer head integrated microfluidic device for facile droplet size control and automatic measurement of a droplet size

A novel microfluidic droplet generator is proposed, which can control the droplet size through turning an integrated micrometer head with ease, and the size of the produced micro-droplet can be automatically and real-time monitored by an open-sourced software and off-the-shelf hardware.     

Uncertainty and Certainty Relations for Pauli Observables in Terms of Renyi Entropies of Order α∈ （0; 1]

We obtain uncertainty and certainty relations of state-independent form for the three Paufi observables with use of the Renyi entropies of order α∈ （0; 1]. It is shown that these entropic bounds are tight in the sense that they are always reached with certain pure states. A new result is the condition for equality in Renyi-entropy uncertainty relations for the Pauli observables. Upper entropic bounds in the pure-state case are also novel. Combining the presented bounds leads to a band, in which the rescaled average Renyi a-entropy ranges for a pure measured state. A width of this band is compared with the Tsallis formulation derived previously.     

Electrochemical Determination of Malathion on an Acetylcholinesterase-Modified Glassy Carbon Electrode

An acetylcholinesterase biosensor based on glassy carbon electrode modified with carbon black and pillar[5]arene was used for the determination of malathion after its preliminary oxidation. The contributions of enzyme immobilization and oxidation conditions to the improvement of analytical characteristics of the biosensor were considered and quantified. In optimal conditions, the acetylcholinesterase biosensor allows the determination of 40 pM of malathion with 10?min of incubation and 15 pM with 30?min of incubation. The sensitivity of immobilized enzyme was found to be higher than that the free enzyme due to sorbtional accumulation in the modifier layer. Incomplete oxidation of malathion decreased the sensitivity of the assay. The developed acetylcholinesterase biosensor was validated for the determination of malathion residues in grapes, wine, and peanuts. The recoveries calculated against a high-performance liquid chromatography assay were between 80 and 120% due to possible matrix effects and the simplified extraction protocols.     

Direct determination of δ44/42Ca isotope ratio by ion chromatography/low‐resolution multicollector ICPMS

High‐precision on‐line procedure for measurement of calcium isotopic ratio by coupling ion chromatography to multicollector inductively coupled plasma mass spectrometry was developed. Calcium separation from the sample matrix was achieved on an ion chromatography column—IonPac CS16—ID 3 mm connected with CERS 500 2 mm suppressor and followed by multicollector inductively coupled plasma mass spectrometry calcium isotopic ratio determination. Dry plasma mode was used with Aridus II desolvation system. To sustained samples with high level of total dissolved salts as well as account capacity of applied analytical column, the method has been optimized regarding calcium isotope ratio measurements with low‐resolution mass spectrometry. Mass discrimination and instrument drift were corrected by sample‐standard bracketing method using the ⁴⁴Ca/⁴²Ca isotope ratio of SRM 915a as a standard. Good accuracy and reasonable precision of calcium isotope ratio (generally 0.20‰ [2SD]) were achieved, which are comparable to off‐line Ca separation and continuous measurement. The reproducibility of the proposed analytical procedure was verified by measuring the SRM 915a standard as a sample randomly over 3 months (n = 56). Applicability of the protocol was demonstrated for matrix‐rich natural water samples, coral samples, and bone standard reference materials.