661 research outputs found
Mutton Traceability Method Based on Internet of Things
In order to improve the mutton traceability efficiency for Internet of Things and solve the problem of data transmission, analyzed existing tracking algorithm, proposed the food traceability application model, Petri network model of food traceability and food traceability of time series data of improved K-means algorithm based on the Internet of things. The food traceability application model to convert, integrate and mine the heterogeneous information, implementation of the food safety traceability information management, Petri network model for food traceability in the process of the state transition were analyzed and simulated and provides a theoretical basis to study the behavior described in the food traceability system and structural design. The experiments on simulation data show that the proposed traceability method based on Internet of Things is more effective for mutton traceability data than the traditional K-means methods
Poly[methanoltetrakis[μ3-5-(4-methoxyphenyl)pyrazole-3-carboxylato(2−)]tricopper(II)disodium(I)
The asymmetric unit of the polymeric title complex, [Cu3Na2(C11H8N2O3)4(CH4O)]n, consists of two NaI atoms, three CuII atoms, four 5-(4-methoxyphenyl)pyrazole-3-carboxylate ligands and one methanol molecule. The central CuII atom is coordinated by four N atoms from four pyrazole-3-carboxylate ligands, forming a distorted tetrahedral (CuN4) geometry, while each of the other two CuII atoms is coordinated by two O atoms and two N atoms from the two ligands, forming a slightly distorted square-planar (CuN2O2) geometry. Each of the two NaI atoms is coordinated by five O atoms, forming a distorted octahedral geometry; four O atoms are from the carboxylate groups of the three ligands and the remaining O atom is from the methoxy group of the ligand or from the methanol molecule
Bioactive compounds from Rumex plants
Two new naphthalene acylglucosides, rumexneposides A (1) and B (2), together with 12 known
compounds (3-14), were isolated from the roots of Rumex nepalensis. Their structures were established
by chemical and spectroscopic methods. The biological activities of compounds 1-14 as well as an
additional 11 compounds previously isolated from R. nepalensis and Rumex hastatus (15–25) were
evaluated against Mycobacterium tuberculosis, para-aminobenzoic acid (pAba) pathway, and a panel of
human cancer cell lines. The results showed that compound 15 was the most active against M.
tuberculosis with an MIC value of 2.85 mM similar to that of isoniazid. Compound 5 could inhibit pAba
synthetic pathway with an MIC value of 12.6 mM, comparable to that of positive control abyssomicin C,
representing a new example of the rare pAba pathway inhibitors
A controllable superconducting electromechanical oscillator with a suspended membrane
We fabricate a microscale electromechanical system, in which a suspended
superconducting membrane, treated as a mechanical oscillator, capacitively
couples to a superconducting microwave resonator. As the microwave driving
power increases, nonmonotonic dependence of the resonance frequency of the
mechanical oscillator on the driving power has been observed. We also
demonstrate the optical switching of the resonance frequency of the mechanical
oscillator. Theoretical models for qualitative understanding of our
experimental observations are presented. Our experiment may pave the way for
the application of a mechanical oscillator with its resonance frequency
controlled by the electromagnetic and/or optical fields, such as a
microwave-optical interface and a controllable element in a
superqubit-mechanical oscillator hybrid system.Comment: 8 pages,4 figure
Experimental and theoretical investigations of copper (I/II) complexes with triazine-pyrazole derivatives as ligands and their in situ C-N bond cleavage
Two copper complexes, Cu(SCN)(MpzT-(EtO)) (1) (MpzT-(EtO) = L3) and CuCl(HO)(MpzT-O) (2) (MpzT-O = L4) were synthesized by the reaction of 2,4,6-tri(3,5-dimethylpyrazol-1-yl)-1,3,5-triazine (L1) or 2,4,6-tri(1H-pyrazol-1-yl)-1,3,5-triazine (L2) with CuCl·2HO in anhydrous ethanol and methanol, respectively. The complexes were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, single crystal X-ray diffraction and X-ray powder diffraction. The structural characterizations and quantum mechanical calculations of the two complexes were analyzed in detail. It was found that an in site reaction occurred during the synthesis process of complexes 1 and 2, likely due to catalytic property of copper ions which leads to the C-N bond cleavage to generate new organic species, namely, MpzT-(EtO) (L3) and MpzT-O (L4)
High-efficiency single-photon source above the loss-tolerant threshold for efficient linear optical quantum computing
Photon loss is the biggest enemy for scalable photonic quantum information
processing. This problem can be tackled by using quantum error correction,
provided that the overall photon loss is below a threshold of 1/3. However, all
reported on-demand and indistinguishable single-photon sources still fall short
of this threshold. Here, by using tailor shaped laser pulse excitation on a
high-quantum efficiency single quantum dot deterministically coupled to a
tunable open microcavity, we demonstrate a high-performance source with a
single-photon purity of 0.9795(6), photon indistinguishability of 0.9856(13),
and an overall system efficiency of 0.712(18), simultaneously. This source for
the first time reaches the efficiency threshold for scalable photonic quantum
computing. With this source, we further demonstrate 1.89(14) dB intensity
squeezing, and consecutive 40-photon events with 1.67 mHz count rate
High-quality multi-wavelength quantum light sources on silicon nitride micro-ring chip
Multi-wavelength quantum light sources, especially at telecom band, are
extremely desired in quantum information technology. Despite recent impressive
advances, such a quantum light source with high quality remains challenging.
Here we demonstrate a multi-wavelength quantum light source using a silicon
nitride micro-ring with a free spectral range of 200 GHz. The generation of
eight pairs of correlated photons is ensured in a wavelength range of 25.6 nm.
With device optimization and noise-rejecting filters, our source enables the
generation of heralded single-photons - at a rate of 62 kHz with
, and the generation of energy-time entangled
photons - with a visibility of in the Franson interferometer.
These results, at room temperature and telecom wavelength, in a CMOS compatible
platform, represent an important step towards integrated quantum light devices
for the quantum networks.Comment: 7 pages, 4 figure
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