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Chromatographic Fingerprint Analysis of Radix Hedysari Using Supercritical Fluid Chromatography Coupled with Diode Array Detector
摘要： A newly and rapid supercritical ?uid chromatography method for the simultaneous determination of 11 active compounds in Radix Hedysari samples has been developed and validated. Optimum separation was achieved on a HSS SB C18 column with a gradient elution at a ?ow rate of 1.5 mL/min, back pressure of 11.03 Mpa and diode array detector at 260 nm. The results from the quantitative data showed that contents of these 11 active compounds were different from plant regions. Especially the contents of formononetin in the Minxian county are ～6-fold than in wild Radix Hedysari. The chromatographic ?ngerprint of Radix Hedysari was recorded under the same chromatographic condition. Data analytic procedure was performed to differentiate the 25 batches of Radix Hedysari samples. Data from chromatographic ?ngerprint were also analyzed using hierarchical cluster analysis. The results showed that 23 batches of Radix Hedysari samples had a high similarity (> 0.90) and overall 25 batches of sample were divided into two clusters. Moreover, according to the comparison contents of active compounds in each Radix Hedysari samples, the cultivated location of Radix Hedysari was successfully distinguished. This method presented good stability, repeatability and precision and would be a useful and reliable approach for the quality control of Radix Hedysari. Moreover, all target compounds were quanti?ed by ultra-high performance liquid chromatography–time-of-?ight mass spectrometry.
关键词： Radix Hedysari,supercritical ?uid chromatography,hierarchical cluster analysis,chromatographic ?ngerprint,quality control
更新于2025-09-19 17:13:59
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Photoexcitation Processes in Oligomethine Cyanine Dyes for Dye-Sensitized Solar Cellsa??Synthesis and Computational Study
摘要： We report density functional theory (DFT) calculations of three newly synthesized oligomethine cyanine-based dyes as potential TiO2-sensitizers in dye-sensitized solar cells. The three dyes have π-symmetry and the same acceptor side, terminating in the carboxylic anchor, but they differ through the π-bridge and the donor groups. We perform DFT and time-dependent DFT studies and present the electronic structure and optical properties of the dyes alone as well as adsorbed to the TiO2 nanocluster, to provide some predictions on the photovoltaic performance of the system. We analyze theoretically the factors that can influence the short circuit current and the open circuit voltage of the dye-sensitized solar cells. We examine the matching of the absorption spectra of the dye and dye-nanocluster system with the solar irradiation spectrum. We display the energy level diagrams and discuss the alignment between the excited state of the dyes and the conduction band edge of the oxide as well as between the redox level of the electrolyte and the ground state of the dyes. We determine the electron density of the key molecular orbitals and analyze comparatively the electron transfer from the dye to the semiconducting substrate. To put our findings in the right perspective we compare the results of our calculations with those obtained for a coumarin-based dye used in fabricating and testing actual devices, for which experimental data regarding the photovoltaic performance are available.
关键词： optical spectra,titanium dioxide cluster,dye-sensitized solar cells,oligomethine cyanine-based dyes,density functional theory
更新于2025-09-19 17:13:59
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Single‐reference coupled cluster methods for computing excitation energies in large molecules: The efficiency and accuracy of approximations
摘要： While methodological developments in the last decade made it possible to compute coupled cluster (CC) energies including excitations up to a perturbative triples correction for molecules containing several hundred atoms, a similar breakthrough has not yet been reported for excited state computations. Accurate CC methods for excited states are still expensive, although some promising candidates for an efficient and accurate excited state CC method have emerged recently. This review examines the various approximation schemes with particular emphasis on their performance for excitation energies and summarizes the best state-of-the-art results which may pave the way for a robust excited state method applicable to molecules of hundreds of atoms. Among these, special attention will be given to exploiting the techniques of similarity transformation, perturbative approximations as well as integral decomposition, local and embedding techniques within the equation of motion CC framework.
关键词： single reference,coupled cluster,efficiency,excited states,accuracy
更新于2025-09-19 17:13:59
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[IEEE 2019 TEQIP III Sponsored International Conference on Microwave Integrated Circuits, Photonics and Wireless Networks (IMICPW) - Tiruchirappalli, India (2019.5.22-2019.5.24)] 2019 TEQIP III Sponsored International Conference on Microwave Integrated Circuits, Photonics and Wireless Networks (IMICPW) - Energy Efficient Design of Cooperative Communication Enabled Magnetic Induction Based Non-Conventional Wireless Sensor Networks
摘要： Non-conventional media comprising of underground and underwater environment use Wireless Sensor Networks (WSNs). These are used for monitoring, intrusion detection, exploration and sensing. Electromagnetic communication in non-conventional media characterizes high path loss and thus can’t be realized practically . Also, apart from high path loss it experiences ever changing channel behaviour due to soil type, moisture and depth of burial. Magnetic induction (MI)-based communication,a recently explored technique for non-conventional media, addresses the two main considerations for designing cluster-based communication protocols for wireless sensor networks: Lifetime of the network and its ef?ciency in energy parameter. The goal of this paper is to infer the all out total energy utilization for the proposed cooperative communication methodology, where in the quantity of nodes that take an interest in the cluster to cluster cooperative transmission is an arbitrary variable, whose esteem relies upon the intra-cluster channel and noise.
关键词： Total PER,Inter-Cluster Energy,Number of Sensor Nodes,Intra-Cluster Energy
更新于2025-09-16 10:30:52
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[IEEE 2019 16th China International Forum on Solid State Lighting & 2019 International Forum on Wide Bandgap Semiconductors China (SSLChina: IFWS) - Shenzhen, China (2019.11.25-2019.11.27)] 2019 16th China International Forum on Solid State Lighting & 2019 International Forum on Wide Bandgap Semiconductors China (SSLChina: IFWS) - High color rendering index white LEDs fabricated using InP/ZnS green-emitting quantum dots and InP/ZnSe/ZnS red-emitting quantum dots
摘要： This paper presents a 3-D statistical channel impulse response (IR) model for urban line of sight (LOS) and non-LOS channels developed from 28- and 73-GHz ultrawideband propagation measurements in New York City, useful in the design of 5G wireless systems that will operate in both the ultra-high frequency/microwave and millimeter-wave (mmWave) spectrum to increase channel capacities. A 3GPP-like stochastic IR channel model is developed from measured power delay profiles, angle of departure, and angle of arrival power spectra. The extracted statistics are used to implement a channel model and simulator capable of generating 3-D mmWave temporal and spatial channel parameters for arbitrary mmWave carrier frequency, signal bandwidth, and antenna beamwidth. The model presented here faithfully reproduces realistic IRs of measured urban channels, supporting air interface design of mmWave transceivers, filters, and multi-element antenna arrays.
关键词： 5G,28 GHz,3-D ray-tracing,multipath,time cluster (TC),spatial lobe (SL),millimeter-wave (mmWave) propagation,statistical simulator,spatial channel model (SCM),time cluster spatial lobe (TCSL),Channel model,impulse response (IR),73 GHz
更新于2025-09-16 10:30:52
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Optical fiber center module for the KOTO experiment
摘要： We introduce a new Optical Fiber Center Module for the Trigger Upgrade in the KOTO Experiment at J-PARC, Japan. The KOTO DAQ consists of nearly 4000 ADC channels over 18 crates. Running in parallel with the Total Energy based L-1 Trigger, the Cluster Trigger uses cluster bits from all 2716 channels in the CsI detector. For each ADC channel, a number of successive samples are analyzed upon a L-1 Trigger, and a bit is set High when the peak sample is above a defined threshold. These values are calculated inside the 176 CsI-ADC modules, and collected for each crate into a Clock Distribution and Trigger Module. In the first KOTO Cluster Trigger Implementation, a 3-layer Clock Distribution and Trigger Module pyramid scheme was employed to bring all cluster bits in one place. This new Optical Fiber Center is a 6UVME module with 18 SFP transceivers and one Intel Arria 5 FPGA. It can communicate directly with all 18 Clock Distribution and Trigger Modules and generate a cluster map for the entire detector with minimal dead time and latency. Cluster numbers are then calculated and sent to the Trigger Master. They are used in combination with Et, for an enhanced L-1 Trigger decision.
关键词： DAQ,FPGA,Cluster trigger,ADC
更新于2025-09-16 10:30:52
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Cluster Synchronization of Semiconductor Lasers Network with Heterogeneous Coupling Delays
摘要： The cluster synchronization of mutually coupled semiconductor lasers network with heterogeneous delays is systematically investigated, whose applicability is demonstrated by discussing two simple networks and a Gaussian-distribution with network random heterogeneous coupling delays.
关键词： Heterogeneous delays,Cluster synchronization,Random SLs network
更新于2025-09-16 10:30:52
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Emission Properties of Laser Plasma Excited on Molecular-Cluster Carbon Dioxide Jets
摘要： We report on the results of investigation of a gas-jet laser-plasma source of extreme ultraviolet radiation based on a conical supersonic nozzle. As a target, we used molecular-cluster CO2 jets. Different regimes of the gas flow were obtained by varying the gas parameters at the gas inlet and the influence of these regimes on the emission and technical characteristics of the radiation source was analyzed. It has been shown experimentally that radiation emission is intensified upon an increase in the amount of clustered material in the jet.
关键词： EUV radiation intensity,extreme ultraviolet radiation,gas-jet target,molecular-cluster CO2 jets,laser-plasma source
更新于2025-09-16 10:30:52
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Controlled Logic Gate Based on a Four-Node Linear Hybrid Cluster State
摘要： In the case of a large amount of computation, a situation may arise when the intermediate results of calculations need to be stored for a given time. In this work, we show how to create a hybrid atomic-field cluster state and create a controlled gate in such a way that the results of calculations are recorded under long-lived degrees of freedom of an atomic ensemble and can be stored for a long time.
关键词： cluster quantum state,controlled logic gate,one-way computing,quantum memory
更新于2025-09-16 10:30:52
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Robust Detection using sparse laser scanner with Autonomous Race Car
摘要： In this paper, a novel laser detection approach with lower objects is proposed. The detection method is based on RANSAC and another filter. For RANSAC, it detects ground surface and delete it in different driving condition. After that using Cluster, it can divide points into different groups which represents objects. Finally, there is a modified Formula SAE race car designed by author to finish experiment to test approach. We apply cones to combine track and do experiment in a random track to analysis the accuracy of detection.
关键词： autonomous race car,robust detection,RANSAC,objects cluster
更新于2025-09-16 10:30:52