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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-computer interface (BCI) phase-locked-loop (PLL) binary-phase-shift keying (BPSK) power transfer efficiency (PTE)

A 124 dB dynamic range sigma-delta modulator applied to non-invasive EEG acquisition using chopper-modulated input-scaling-down technique

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Science China(Information Sciences) 2022年第4期65卷 23-37页

作者： Kaiquan CHEN Mingyi CHEN Longlong chenG Liang QI Guoxing WANG Yong LIAN Department of Micro/Nano Electronics Shanghai Jiao Tong University China Electronic Cloud Brain (Tianjin) Technology Co. Ltd.

With the advancement of brain science in recent years, the non-invasive brain-computer interfaces（BCIs） based on electroencephalogram（EEG） acquisition have been widely adopted in various brain-inspired applications. The acquisition of multi-channel microvolts EEG signals corrupted by the motion artifacts（MAs） of up to several volts poses enormous challenges to the design of analog front-end（AFE）, especially the analog-to-digital converter（ADC）, which is necessary to achieve low noise, wide dynamic range（DR）,high accuracy as well as low power. In this paper, a wide DR Σ△ modulator with chopper-modulated inputscaling-down（CM-ISD） technique has been proposed to deal with large input offset while extending dynamic range. Fabricated in 180 nm CMOS technology, the prototype occupies a core area of 0.32 mm;. With a 40 Hz input signal and 125 Hz Nyquist bandwidth, the measured signal-to-noise ratio（SNR） and signalto-noise and distortion ratio（SNDR） are 117 and 110 dB, respectively. Thanks to the proposed CM-ISD technique, the modulator is capable of withstanding a full-scale(4.5 V;) input whereas the measured DR has been extended from 99 to 124 dB. The power consumption is 2.75 mW under 5 V supply voltage,corresponding to 170.6 dB Schreier figure-of-merit（FoMS）. The multi-channel EEG acquisition has been demonstrated based on the proposed modulator, showing its potential in advanced non-invasive BCI systems.

关键词： Analog-to-digital converter (ADC) ΣΔ modulator brain computer interface electroencephalogram dynamic range motion artifacts

Research on EEG emotion recognition based on CNN+BiLSTM+self-attention model

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Optoelectronics Letters 2023年第8期19卷 506-512页

作者： LI Xueqing LI Penghai FANG Zhendong cheng longlong WANG Zhiyong WANG Weijie School of Integrated Circuit Science and Engineering Tianjin University of TechnologyTianjin 300384China China France BOHAI Geoservices Co. Ltd.Tianjin 300457China China Electronics Cloud Brain(Tianjin)Technology Co. Ltd.TianjinChina Institute of Motion Analysis and Research University of DundeeScotland DD14HNUK

To address the problems of insufficient dimensionality of electroencephalogram(EEG) feature extraction,the tendency to ignore the importance of different sequential data segments,and the poor generalization ability of the model in EEG based emotion recognition,the model of convolutional neural network and bi-directional long short-term memory and self-attention(CNN+Bi LSTM+self-attention) is proposed.This model uses convolutional neural network(CNN) to extract more distinctive features from both spatial and temporal dimensions.The bi-directional long short-term memory(Bi LSTM) is used to further preserve the long-term dependencies between the temporal phases of sequential data.The self-attention mechanism can change the weights of different channels to extract and highlight important information and address the often-ignored importance of different channels and samples when extracting EEG features.The subject-dependent experiment and subject-independent experiment are performed on the database for emotion analysis using physiological signals(DEAP) and collected datasets to verify the recognition performance.The experimental results show that the model proposed in this paper has excellent recognition performance and generalization ability.

关键词： EEG weights LSTM

Rapid fatty acids detection of vegetable oils by Raman spectroscopy based on competitive adaptive reweighted sampling coupled with support vector regression

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Food Quality and Safety 2022年第4期6卷 545-554页

作者： Linjiang Pang Hui Chen Liqing Yin Jiyu cheng Jiande Jin Honghui Zhao Zhihao Liu longlong Dong Huichun Yu Xinghua Lu College of Food and Health Zhejiang A&F UniversityHangzhouChina College of Food&Bioengineering Henan University of Science and TechnologyLuoyangChina Zhejiang Provincial Grain Breau of Grain and Oil Reserve HangzhouChina

Objectives:The composition and content of fatty acids are critical indicators of vegetable oil quality.To overcome the drawbacks of traditional detection methods,Raman spectroscopy was investigated for the fast determination of the fatty acids composition of oil.Materials and Methods:Rapeseed and soybean oil at different depths of the oil tank at different storage times were collected and an eighth-degree polynomial function was used to fit the Raman spectrum.Then,the multivariate scattering correction,standard normal variable transformation(SNV),and Savitzky–Golay convolution smoothing methods were compared.Results:Polynomial fitting combined with SNV was found to be the optimal pretreatment method.Characteristic wavelengths were selected by competitive adaptive reweighted sampling.For monounsaturated fatty acids(MUFAs),polyunsaturated fatty acids(PUFAs),and saturated fatty acids(SFAs),44,75,and 92 characteristic wavelengths of rapeseed oil,and 60,114,and 60 characteristic wavelengths of soybean oil were extracted.Support vector regression was used to establish the prediction model.The R^(2)values of the prediction results of MUFAs,PUFAs,and SFAs for rapeseed oil were 0.9670,0.9568,and 0.9553,and the root mean square error(RMSE)values were 0.0273,0.0326,and 0.0340,respectively.The R^(2)values of the prediction results of fatty acids for soybean oil were respectively 0.9414,0.9562,and 0.9422,and RMSE values were 0.0460,0.0378,and 0.0548,respectively.A good correlation coefficient and small RMSE value were obtained,indicating the results to be highly accurate and reliable.Conclusions:Raman spectroscopy,based on competitive adaptive reweighted sampling coupled with support vector regression,can rapidly and accurately analyze the fatty acid composition of vegetable oil.

关键词： Raman spectroscopy fatty acid composition competitive adaptive reweighted sampling support vector regression

Electric modulation of conduction in MAPbBr_(3) single crystals

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Journal of Advanced Ceramics 2021年第2期10卷 320-327页

作者： Shanming Ke Shangyu Luo Jinhui Gong Liwen Qiu Renhong Liang Yangbo Zhou Bingcheng Luo Baochang cheng Li Wang longlong Shu School of Materials Science and Engineering Nanchang UniversityNanchang330031China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China

The resistive switching(RS)mechanism of hybrid organic–inorganic perovskites has not been clearly understood until now.A switchable diode-like RS behavior in MAPbBr3 single crystals using Au(or Pt)symmetric electrodes is reported.Both the high resistance state(HRS)and low resistance state(LRS)are electrode-area dependent and light responsive.We propose an electric-fielddriven inner p–n junction accompanied by a trap-controlled space-charge-limited conduction(SCLC)conduction mechanism to explain this switchable diode-like RS behavior in MAPbBr_(3) single crystals.

关键词： resistive switching(RS) rectifying behavior hybrid organic–inorganic perovskites p–n structure

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软土地基PHC管桩偏位研究

港工技术 2022年第1期59卷 95-98页

作者：成建强唐龙龙中交第一航务工程勘察设计院有限公司天津300220

本文以某生产污水处理站桩基施工过程中及施工完成后桩基发生偏位为例,通过研究分析工程概况、工程地质情况、施工过程以及检测结果,着重对软土地基PHC管桩偏位的原因进行分析,并给出避免类似问题的建议。对类似工程施工有一定借鉴意义。

关键词： PHC管桩软土地基偏位

Facile synthesis of hydrochar-supported catalysts from glucose and its catalytic activity towards the production of functional amines

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Green Energy & Environment 2023年第5期8卷 1358-1370页

作者： Xiuzheng Zhuang Jianguo Liu longlong Ma Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing210096China Key Laboratory of Renewable Energy Guangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou510640China

Since the utilization of abundant biomass to develop advanced materials has become an utmost priority in recent years,we developed two sustainable routes(i.e.,the impregnation method and the one-pot synthesis)to prepare the hydrochar-supported catalysts and tested its catalytic performance on the reductive amination.Several techniques,such as TEM,XRD and XPS,were adopted to characterize the structural and catalytic features of samples.Results indicated that the impregnation method favors the formation of outer-sphere surface complexes with porous structure as well as well-distributed metallic nanoparticles,while the one-pot synthesis tends to form the inner-sphere surface complexes with relatively smooth appearance and amorphous metals.This difference explains the better activity of catalysts prepared by the impregnation method which can selectively convert benzaldehyde to benzylamine with an excellent yield of 93.7%under the optimal reaction conditions;in contrast,the catalyst prepared by the one-pot synthesis only exhibits a low selectivity near to zero.Furthermore,the gram-scale test catalyzed by the same catalysts exhibits a similar yield of benzylamine in comparison to its smaller scale,which is comparable to the previously reported heterogeneous noble-based catalysts.More surprisingly,the prepared catalysts can be expediently recycled by a magnetic bar and remain the satisfying catalytic activity after reusing up to five times.In conclusion,these developed catalysts enable the synthesis of functional amines with excellent selectivity and carbon balance,proving cost-effective and sustainable access to the wide application of reductive amination.

关键词： Impregnation method One-pot synthesis Hydrochar-supported catalyst Reductive amination

Nickel-catalyzed reductive cross-coupling of polyfluoroarenes with alkyl electrophiles by site-selective C–F bond activation

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Chinese Chemical Letters 2022年第9期33卷 4287-4292页

作者： longlong Xi Liting Du Zhuangzhi Shi State Key Laboratory of Coordination Chemistry Chemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China Advanced Analysis and Testing Center Nanjing Forestry UniversityNanjing 210037China

A nickel-catalyzed reductive cross-coupling reactions between polyfluoroarenes and alkyl electrophiles is reported to access substituted fluoroarenes through chelation-assisted C–F activation.Diverse primary and secondary alkyl(pseudo)halides can be employed to couple with polyfluoroarenes,showing excellent regioselectivity.Furthermore,the nickel-catalyzed asymmetric cross-coupling of polyfluoroarenes with racemic alkyl halides is preliminarily explored.In addition,the practicability of the title transformation is also demonstrated by total synthesis of losmapimod and an analog as key steps.The developed method exhibits many advantages,including economic catalytic systems,commercially available alkyl electrophiles,and lack of sensitive organometallic reagents.

关键词： Polyfluoroarenes Nickel Alkylation Cross-coupling C-F activation

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中型智能油压机高效节能控制系统的设计

机床与液压 2015年第7期43卷 119-123页

作者：郑龙龙程良伦广东工业大学自动化学院广东广州510006 广东工业大学计算机学院广东广州510006

针对传统油压机锻造工件工作过程中,运行速度都是在工频状态下运行,整个系统在工作过程中能耗消耗较大的现状,提出一种基于平流层PLC的变频调速控制方式。该控制方式通过控制油压机在不同的工作阶段以不同的速度运行,并在待机时刻保持... 详细信息

针对传统油压机锻造工件工作过程中,运行速度都是在工频状态下运行,整个系统在工作过程中能耗消耗较大的现状,提出一种基于平流层PLC的变频调速控制方式。该控制方式通过控制油压机在不同的工作阶段以不同的速度运行,并在待机时刻保持低速运行,使得油压机不仅能保证稳定工作,还能通过不同的速度选择降低能耗,达到节能的目的。经过现场测试,该控制方式相对于传统的油压机控制能有效降低噪声,节能效果达到20%左右。

关键词：智能油压机变频调速高效节能

Anoctamin 4 defines glucose-inhibited neurons in the ventromedial hypothalamus

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Neural Regeneration Research 2024年第6期19卷 1177-1178页

作者： longlong Tu Yanlin He Yong Xu Children's Nutrition Research Center Department of Pediatrics Baylor College of Medicine Department of Molecular and Cellular Biology Section of Endocrinology Diabetes and Metabolism Department of Medicine Baylor College of Medicine Brain Glycemic and Metabolism Control Department Pennington Biomedical Research Center Louisiana State University

Glucose is the primary fuel source of the brain,and therefore glucose levels need to be tightly regulated and maintained within a small physiological range.Certainly,the body necessitates a stable supply of energy mainly provided by glucose for various bodily functions.High or low blood glucose levels would impair the physiological functions of various organs of the body.Prolonged high blood glucose(i.e.,

关键词： HYPOGLYCEMIA