143 research outputs found
HKJ805668_appendix1 – Supplemental material for The value of ultrasound in diagnosis of pneumoperitoneum in emergent or critical conditions: A meta-analysis
No full textSupplemental material, HKJ805668_appendix1 for The value of ultrasound in diagnosis of pneumoperitoneum in emergent or critical conditions: A meta-analysis by Libing Jiang, Jing Wu and Xia Feng in Hong Kong Journal of Emergency Medicine</p
HKJ805668_appendix2 – Supplemental material for The value of ultrasound in diagnosis of pneumoperitoneum in emergent or critical conditions: A meta-analysis
No full textSupplemental material, HKJ805668_appendix2 for The value of ultrasound in diagnosis of pneumoperitoneum in emergent or critical conditions: A meta-analysis by Libing Jiang, Jing Wu and Xia Feng in Hong Kong Journal of Emergency Medicine</p
PCNNCEC: Efficient and Privacy-Preserving Convolutional Neural Network Inference Based on Cloud-Edge-Client Collaboration
No full textPCNNCEC: Efficient and Privacy-Preserving Convolutional Neural Network Inference Based on Cloud-Edge-Client Collaboration
No full textNew reactions and strategies in divergent syntheses of macrolide antibiotics
No full textFrom the microbial world, antibiotics are structurally complex and highly potent chemical weapons that co-evolved with bacteria. Macrolide (glycosylated cyclic polyketides) antibiotics have been used extensively as first-line antibacterial agents since the discovery of the broad-spectrum antibiotic erythromycin A in 1952. However wide-spread use of antibiotics has led pathogens to develop drug resistance. Therefore new and enhanced antibiotics are constantly in need. Described in this dissertation is my effort to emulate the synthetic capabilities of erythromycin-producing bacteria by accessing novel erythromycin-inspired polyketides via divergent total synthesis. New allene oxidation methods have been developed and implemented in a modular and divergent route to produce a diversified portfolio of cyclic polyketides and their glycoconjugates. I will disclose a total synthesis of 4,10-didesmethyl-(9S)-dihydroerythronolide A (Chapter 2), preparation of glycosylated erythromycin analogs (Chapter 3) and progress towards synthesis of 9(S)-dihydroerythronolide A (Chapter 4).Ph.D.Includes bibliographical referencesby Libing Y
Research on the relationship between the elements and pharmacological activities in velvet antler using factor analysis and cluster analysis
No full textGeochemistry of the Tianger shear zone-hosted gold deposit (west Tianshan, northwest China)
No full textTheWangfeng-Tianger-Saridala gold district consists of over 20 ore bodies and occurs in the EW-trending Tianger shear zone in the western Tianshan Mountains. Shear zone-controlled old mineralization occurs in mylonitized granites and mylonitized sulficle-mica - quartz veins. The ore bodies are composed of gold - bearing mylonitized granites and gold - bearing sulfide - quartz veins in the central part of the Tianger shearzone.Gold grade strongly correlates with the abundance of sulfide - quartz veins. Native gold grains are rarely found in adjacent wall rocks. Pyrite and pyrrhotite in gold bearing sulfide - quartz veins contain native gold inclusions. Chondrite-normalized rare earth element (REE) distribution patterns for pyrite from orebodies show apparent light REE enrichment and negative Eu anomalies.The relations between gold contents andTh/U,Zr/ Hf and (La/Yb)(N) values for pyrite imply that the gold-rich pyrite is different from the gold-poor pyrite, and thus indicates that pyrite in ore-body has a different origin when compared with pyrite in wall rocks. Gold has been introduced syn-deformationally during a period of ductile-brittle shear development.A Rb-Sr isotopic isochrone composed of 4 mica samples, 1 quartz sample, and 5 whole rock samples in mylonitized gold-bearing quartz veins produces one isochrone age of 224 +/- 14 Ma with an initial Sr-86/Sr-87 ratio of 0.7294 +/- 0.0089 (MSWD = 1.1).http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000237245800289&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701GeologyMining & Mineral ProcessingCPCI-S(ISTP)
Stability Analysis of Magnetic Gear with Thin Metal Sheet
No full textIn the transmission process of coaxial magnetic gear, aiming at the problems of large torque ripple and high magnetic density in air-gap, a magnetic gear with thin metal sheet is studied. The structure fixates a layer of conductive and non-magnetic metal material respectively on the internal and external permanent magnets of the rotor in the magnetic gear. A magnetic gear model with 4 opposite poles for inner rotor and 21 opposite poles for outer rotor is established via finite element method. The internal and external air-gap magnetic field and torque of the magnetic gear are calculated. Meanwhile, high magnetic density and torque ripple are analyzed. The results demonstrate that the magnetic gear with metal sheet can not only reduce the high-order harmonic components of magnetic density but also reduce the torque ripple. A reference for the improvement of the stability in the magnetic gear transmission is provided
Influence of Number of Pole Pairs on Torque Ripple of Magnetic Gear
No full textThe field modulation magnetic gear is a kind of transmission device with broad development prospects. It has the advantages of no friction， no pollution， less maintenance and easy installation. The magnetic gear models with different transmission ratio are established. The input and output torque waveforms of different models are compared. The influences of the number of pole pairs of inner rotor （P1） and the number of pole pairs of outer rotor （P2） on torque ripple are analyzed. According to the principle of magnetic field modulation and spatial magnetic field harmonic distribution， the torque ripple of magnetic gear is greatly affected by P1 and P2. The research results show that the torque ripple can be effectively reduced by selecting the magnetic gear with P1=4， P1:P2=1:n+0.25 or 1:n+0.75 （n is a natural number）
A Novel High Performance Magnetic Gear with Auxiliary Silicon Steel Sheet
No full textMagnetic gear is a transmission device with novel structure. It uses the principle of magnetic field modulation to transmit torque. In view of the magnetic leakage of the magnetic gear in the process of rotation and cannot be eliminated, a magnetic gear model with auxiliary silicon steel sheet is proposed. Based on the conventional magnetic gear structure, the silicon steel sheet is placed outside the permanent magnet of the outer rotor. The magnetization mode of the outer rotor permanent magnet is tangential magnetization, and the spoke structure is adopted, and the inner rotor PMs is surface mounted and magnetized in the radial magnetization. The improved model is simulated by finite element method under three-dimensional conditions, and the electromagnetic performances of the model are optimized. Compared with the conventional magnetic gear model, the improved model has good performance, which improves the transmission capacity of output torque and reduces torque ripple. It is a great significance to improve the performance of magnetic gear
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