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A 70%-power transmission efficiency, 3.39 Mbps power and data telemetry over a single 13.56 MHz inductive link for biomedical implants

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Science China(Information Sciences) 2023年第2期66卷 237-249页

作者： Mingyi CHEN Luominghao PAN Qiuyang LIN Longlong CHENG Dong MING Department of Micro/Nano Electronics Shanghai Jiao Tong University IMEC China Electronic Cloud Brain (Tianjin) Technology co. Ltd. Neural Engineering & Rehabilitation Engineering Laboratory Tianjin University

The application of wireless power and data telemetry to implantable medical devices(IMDs)has grown dramatically in recent decades. Achieving a high data rate and high-power transmission efficiency(PTE) over the same inductive link remains challenging. This paper presents a power and data telemetry circuit over a single 13.56 MHz inductive link. On the transmitter(TX) side, a binary-phase-shift keying(BPSK) modulation based on a Class-E amplifier that features a high modulation rate and a high quality(Q)-factor is proposed. A digital-assisted phase-locked-loop(PLL) is proposed on the receiver(RX) side as a BPSK demodulator to handle the long settling process. The maximum data rate can be extended to 1/4 of the carrier frequency. The prototype has been fabricated with a 180 nm BCD(Bipolar-CMOS-DMOS)process. The measurement shows that up to 31.25 mW of power can be delivered simultaneously with 3.39-Mbps of data transmission, while a 2×10-7bit-error-rate(BER) can be ensured over a transmission distance of 5 mm. The peak PTE is 70%, whereas the RX energy efficiency is 183 p J/bit. The results demonstrate the potential of the proposed techniques in applications to various biomedical implants with intensive bandwidth and energy efficiency requirements.

关键词： power and data telemetry inductive link implantable medical device (IMD) brain-co.puter interface (BCI) phase-locked-loop (PLL) binary-phase-shift keying (BPSK) power transfer efficiency (PTE)

Tribological performance of novel nickel-based co.posite co.tings with lubricant particles

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Friction 2019年第2期7卷 169-180页

作者： Ignacio TUDELA Andrew J.co.LEY Yi ZHANG Daido Metal co. Ltd.European Technical Centre UKResearch & Development Department Functional Materials Research Centre for Manufacturing and Materials EngineeringFaculty of EngineeringEnvironment and ComputingCoventry University

The present study is focused on the evaluation of the tribological performance of novel Ni/h BN and Ni/WS_2 co.posite co.tings electrodeposited from an additive-free Watts bath with the assistance of ultrasound. Lubricated and non-lubricated scratch tests were performed on both novel co.posite co.tings and on standard Ni deposits used as a benchmark co.ting to have an initial idea of the effect of the presence of particles within the Ni matrix. Under lubricated co.ditions, the performance of the Ni/h BN co.posite co.ting was very similar to the benchmark Ni co.ting, whereas the Ni/WS_2 behaved quite differently, as the latter did not only show a lower co.fficient of friction, but also prevented the occurrence of stick-slip motion that was clearly observed in the other co.tings. Under non-lubricated co.ditions, whereas the tribological performance of the Ni/hBN co.posite co.ting was again very similar to that of the benchmark Ni co.ting, the Ni/WS_2 co.posite co.tings again showed a remarkable enhancement, as the inco.poration of the WS_2 particles into the Ni co.ting not only resulted in a lower co.fficient of friction, but also in the prevention of co.ting failure.

关键词： nickel tungsten disulphide hexagonal boron nitride co.posite co.tings solid lubricant tribology

Synthesis, Characterization and Formation Mechanism of Friedel's Salt(FS:3CaO·A1_2O_3·CaCl_2·10H_2O) by the Reaction of Calcium Chloride with Sodium Aluminate

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Journal of Wuhan University of Technology(Materials Science) 2015年第1期30卷 76-83页

作者：马家玉 LI Zhibao JIANG Yuehua YANG Xiaoping National Engineering and Technology Research Centre for Aluminium & Magnesium Electrolysis Facilities Guiyang Aluminium Magnesium Design & Research Institute Co. Ltd. Key Laboratory for Green Chemical Process of Ministry of Education Wuhan Institute of Technology Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences Shenyang Aluminium & Magnesium Engineering & Research Institute co. Ltd.

The synthesis of Friedel＇s salt （FS： 3CaO·Al2O3·CaCl2·10H2O） by the reaction of calcium chloride with sodium aluminate was investigated. Factors affecting the preparation of Friedel＇s salt, such as reaction temperature, initial co.centration, titration speed, aging time and molar Ca/Al ratio were studied in detail. XRD, SEM images and particle size distribution show that the reaction temperature, aging time and molar Ca/Al ratio have significant effect on the co.position, crystal morphology, and average particle size of the obtained samples. In addition, the initial CaCl2 co.centration and NaAlO2 titration speed do not significantly influence the morphology and particle size distribution of Friedel＇s salt. With the optimization of the operating co.ditions, the crystals can grow up to a average size of about 28 μm, showing flat hexagonal （or pseudo- hexagonal） crystal morphology. Moreover, two potential mechanisms of Friedel＇s salt formation including adsorption mechanism and anion-exchange mechanism were discussed. In the adsorption mechanism, Friedel＇s salt forms due to the adsorption of the bulk C1- ions present in the solution into the interlayers of the principal layers, [Ca2Al（OH-）6·2H2O]＋, in order to balance the charge. In the anion-exchange mechanism, the freechloride ions bind with the AFro （a family of hydrated co.pounds found in cement） hydrates to form Friedel＇s salt by anion-exchange with the ions present in the interlayers of the principal layer, [Ca2Al（OH-）6. 2H2O]＋- OH-.

关键词： synthesis characterization formation mechanism Friedel's salt

Transmit Diversity Scheme Design for Rectangular Pulse Shaping Based OTFS

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China co.munications 2022年第3期19卷 116-128页

作者： Dong Wang Bule Sun Fanggang Wang Xiran Li Pu Yuan Dajie Jiang State Key Laboratory of Rail Traffic co.trol and Safety Beijing Jiaotong UniversityBeijing 00044China vivo Mobile co.munication co. Ltd.Beijing 100016China

This paper investigates the transmission scheme of the orthogonal time frequency space(OTFS)system with multiple *** works have studied the multi-antenna transmitter diversity scheme with the ideal pulse shaping in OTFS systems assuming the wireless channels of two co.secutive frames duration are ***,the ideal pulse shaping can not be realized in practice and the channel varies rapidly in two co.secutive frames in the high-speed mobility *** this end,we redesign the multi-antenna transmitter diversity scheme to ensure its practicability in the rectangular-pulsebased OTFS *** first,the information symbols of each antenna are divided into two half frames along the Doppler ***,the guard symbols are carefully arranged to eliminate the interference between two half frames,and to ensure the equivalent channels of two half frames being *** co.sidering the positions of the guard symbols,the transmission co.eword is designed and a low co.plexity linear detection is ***,simulation results validate that the bit error rate performance of the proposed scheme has the superiority over the existing works.

关键词： guard symbols multiple antennas OTFS transmit diversity

PetroChina's Obvious Progress in E&P

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China Oil & Gas 2002年第3期9卷 16-21页

作者： Zhao Xianzheng and Wang Heying (Exploration & Production co., PetroChina) Exploration & Production co. PetroChina

In 2002, PetroChina have made obvious progress since it began to carry forward integrated exploration and development, in the first half year, exploration and development have gained a series of achievements through optimizing deployment,deepening geological research, strengthening technological innovation, organizing elaborately and arranging carefully.

关键词： PetroChina’s Obvious Progress in E&P well high

co.pling Effect of Heat Transfer and Flow Resistance in the Rifled Tube Water Wall of a Ultra-Supercritical CFB Boiler

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Journal of Thermal Science 2019年第5期28卷 1078-1088页

作者： LI Yaode YANG Dong OUYANG Shijie LIU Dan WANG Wenyu State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China North China Electric Power Test and Research Institute co. Ltd Tianjing 300000 China

The co.pling factor is used in this study to characterise the co.bined effect of the heat transfer and resistance characteristics of a rifled tube. Boundary layer theory is utilised to investigate the relationship between the co.prehensive co.fficient and Reynolds number in two regions, namely, higher and lower than pseudo-critical enthalpy. Results indicate that mass flux exerts a decisive negative influence on the co.pling effect, and the impacts of pressure and heat flux are weak. The overall effect decreases rapidly as the mass flux increases, but it increases in the area behind the quasi-critical enthalpy. The co.pling effect is also affected by specific heat ratio, thermal acceleration and buoyancy. The co.relations of heat transfer and friction resistance are deduced with high precision acco.ding to experimental data.

关键词： supercritical pressure heat transfer frictional resistance co.pling effect

Thermodynamic property of sandwich cylindrical shell structure with metallic wire mesh:Numerical modeling and experimental analysis

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Chinese Journal of Aeronautics 2024年第1期37卷 138-152页

作者： Xin XUE Guojian SHEN Juan LIAO Institute of Metal Rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350116China Fujian Shuikou Power Generation Group co. LTDFuzhou 350000China

As a new addition to lightweight co.posite structures,the sandwich cylindrical shell with a metallic wire mesh co.e has emerged as a promising solution for thermodynamic performance analysis at elevated *** intricate interwoven cellular formations within the metallic wire mesh pose difficulties for thermo-mechanical modeling and property ***,the co.stitutive models employed to characterize hysteresis phenomena were presented,co.prising isotropic elasticity,Bergstrom-Boyce model,Ogden hyper-elasticity,and parameter identification through mechanical examinations at varying ***,the finite element modeling of cylindrical shell structures was determined for modal and steady-state dynamic ***,the experimental procedures were carried out,including the preparation of the sandwich cylindrical shell and the dynamic testing *** first-order natural frequency of the cylindrical shell structure is close to the resonance frequency of the dynamic test results,with a maximum error of 6.5%,demonstrating the accuracy of the simulation *** co.pared to the solid-co.e cylindrical shell,the average insertion loss of the sandwich cylindrical shell structure within the frequency range of 10–1000 Hz at room temperature is up to 11.09 ***,at elevated temperatures,the average insertion loss of the sandwich cylindrical shell decreases but fluctuates as the temperature changes.

关键词： Energy dissipation Metallic matrix co.posites Numerical analysis Sandwich structure Thermodynamic properties

Thermally induced evolution of phase transformations in gas hydrate sediment

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Science China(Physics,Mechanics & Astronomy) 2010年第8期53卷 1530-1535页

作者： ZHANG XuHui LU XiaoBing LI QingPing YAO HaiYuan Key Laboratory for Hydrodynamics and Ocean Engineering Institute of MechanicsChinese Academy of SciencesBeijing 100190China Research Centre China Ocean Oil Co.Beijing 100027China

Thermally induced evolution of phase transformations is a basic physical-chemical process in the dissociation of gas hydrate in sediment (GHS). Heat transfer leads to the weakening of the bed soil and the simultaneous establishment of a time varying stress field acco.panied by seepage of fluids and deformation of the soil. As a co.sequence, ground failure co.ld occur causing engineering damage or/and environmental disaster. This paper presents a simplified analysis of the thermal process by assuming that thermal co.duction can be deco.pled from the flow and deformation process. It is further assumed that phase transformations take place instantaneously. Analytical and numerical results are given for several examples of simplified geometry. Experiments using Tetra-hydro-furan hydrate sediments were carried out in our laboratory to check the theory. By co.parison, the theoretical, numerical and experimental results on the evolution of dissociation fronts and temperature in the sediment are found to be in good agreement.

关键词： gas hydrate dissociation front phase transformation thermal co.duction

Separation and simultaneous quantitation of PGF2α and its epimer 8-iso-PGF2α using modifier-assisted differential mobility spectrometry tandem mass spectrometry

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Acta Pharmaceutica Sinica B 2018年第2期8卷 228-234页

作者： Chunsu Liang Hui Sun Xiangjun Meng Lei Yina J.Paul Fawcett Huaidong Yu Ting Liu Jingkai Gu Research Center for Drug Metabolism School of Life Sciences Jilin University School of Pharmacy University of Otago Shanghai AB Sciex Analytical Instrument Trading co. Ltd.

Because many therapeutic agents are co.taminated by epimeric impurities or form epimers as a result of metabolism, analytical tools capable of determining epimers are increasingly in demand. This article is a proof-of-principle report of a novel DMS–MS/MS method to separate and simultaneously quantify epimers, taking PGF2α and its 8-epimer, 8-iso-PGF2α, as an example. Good accuracy and precision were achieved in the range of 10–500 ng/m L with a run time of only 1.5 min. Isopropanol as organic modifier facilitated a good co.bination of sensitivity and separation. The method is the first example of the quantitation of epimers without chromatographic separation.

关键词： Differential mobility spectrometry Mass spectrometry Epimer PGF2α 8-iso-PGF2α