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De-noising of radiation pressure signal generated by bubble oscillation based on ensemble empirical mode decomposition

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Journal of Hydrodynamics 2022年第5期34卷 849-863页

作者： xiang-hao zheng Yu-ning Zhang Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of EnergyPower and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The radiation pressure signals generated by the bubble oscillation are often utilized to recognize the characteristics of the target objects in many ***,these signals are easily contaminated by complex background *** order to accurately extract the effective components of the radiation pressure signal generated by the bubble oscillation,this paper proposes a de-noising procedure for the radiation pressure signal,based on the ensemble empirical mode decomposition(EEMD),the autocorrelation function and the modified wavelet soft-threshold de-noising *** order to verify the effectiveness of the procedure,the typical radiation pressure signal generated based on the Keller-Miksis model under the acoustic excitation is employed for the subsequent de-noising *** results of the qualitative analysis show that the amplitude and the period of the bubble oscillation can be clearly observed in the time-domain diagram of the de-noised signal based on the *** the quantitative analysis,the de-noised signal based on the EEMD has better performance with higher signal-to-noise ratio(SNR),smaller root-mean-square error,and larger correlation coefficient than that based on the wavelet transform(WT)and the empirical mode decomposition(EMD).Furthermore,with the increase of the complexity of the radiation pressure signal(e.g.,the increase of the dimensionless pressure amplitude of the acoustic wave and the decrease of the SNR of the input signal),the above three evaluation indexes of the de-noised signal based on the EEMD are all better than those based on the other two *** the signal is more complex,the de-noising capabilities of the WT,the EMD are greatly reduced,but the EEMD can still maintain the good de-noising capability,which shows the superiority of the signal de-noising procedure proposed in the present paper.

关键词： Radiation pressure cavitation bubble oscillation signal de-noising ensemble empirical mode decomposition(EEMD) autocorrelation function wavelet soft-threshold de-noising

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生物反馈助力电刺激对慢性非特异性腰痛患者下肢步行功能的改善

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中国组织工程研究 2025年第3期29卷 547-553页

作者：郑翔张明兴黄雅单莎瑞广东药科大学附属第一医院广东省广州市510080

背景:国内外关于慢性非特异性腰痛生物反馈疗法和三维步态功能分析的相关研究已开展很多,但是对二者结合的研究少有报道。目的:利用三维步态分析采集步态参数数据,研究生物反馈助力电刺激对慢性非特异性腰痛患者步行能力的改变效果。方... 详细信息

背景:国内外关于慢性非特异性腰痛生物反馈疗法和三维步态功能分析的相关研究已开展很多,但是对二者结合的研究少有报道。目的:利用三维步态分析采集步态参数数据,研究生物反馈助力电刺激对慢性非特异性腰痛患者步行能力的改变效果。方法:选择2021年6月至2022年9月在广东药科大学附属第一医院收治的60例慢性非特异性腰痛患者,男34例,女26例,年龄32-58岁。采用随机数字表法将60例患者分为对照组(n=30)与试验组(n=30),两组患者均接受腰部动态干扰电的常规治疗(20 min/次,1次/d,每周5次,持续治疗20次),对照组患者在常规治疗的基础上进行仰卧搭桥和俯卧搭桥的悬吊核心肌群训练(每周5次,持续治疗20次),试验组在对照组治疗的基础上进行生物反馈助力电刺激治疗(20 min/次,1次/d,每周5次,持续治疗20次)。比较分析两组患者治疗前后的腰痛评分、肌电信号平均值和步态参数。结果与结论:①两组患者治疗结束后的数字类比表评分、日本骨科协会(JOA)评分、Oswestry功能障碍指数均较治疗前明显改善(P<0.05),试验组治疗结束后的数字类比表评分、JOA评分、Oswestry功能障碍指数均优于对照组(P<0.05);②两组患者治疗结束后的腹直肌、臀大肌、竖脊肌表面肌电平均值均高于治疗前(P<0.05),试验组治疗结束后的腹直肌、臀大肌、竖脊肌表面肌电平均值均高于对照组(P<0.05);③两组患者治疗结束后的步宽、步速、步频、健患侧步长比值、健患侧支撑相比值、患健侧摆动相比值、健患侧髋关节及膝关节矢状面活动度和健患侧足偏角均优于治疗前(P<0.05),试验组治疗结束后的上述指标均优于对照组(P<0.05);④结果表明,生物反馈助力电刺激能明显缓解慢性非特异性腰痛,改善了患者下肢步行功能。

关键词：三维步态生物反馈助力电刺激慢性非特异性腰痛步行功能核心稳定训练

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Studies on the Quantitative Structure-activity Relationship of Substituted Biphenyls by Density Function Theory (DFT)

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Chinese Journal of Structural Chemistry 2007年第2期26卷 229-233页

作者： HAN xiang-Yun zheng Qing Department of Chemical Engineering YanchengInstitute of Technology Jiangsu 224003 China

Geometrical configurations of 16 substituted biphenyls were computed at the B3LYP/6-311G^＊＊ level with Gaussian 98 program. Based on linear solvation energy theory, lgKow as well as the structural and thermodynamic parameters obtained at this level was taken as theoretical descriptors, and corresponding equation predicting the toxicity of Daphnia magna （-lgEC5o） was thus obtained, in which three parameters were contained, i.e., n-octanol/water partition coefficients （lgKow）, dipole moment of the molecules（ μ） and entropy （S°）. For this equation, R^2 = 0.9582, q^2 = 0.8921 and SD = 0.102. The absolute t-scores of three variables are larger than the standard one in the confidence range of 95%, which confirms the creditability and stability of this model.

关键词： substituted biphenyl linear solvation energy theory,DFT method Daphnia magna toxicity

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Effects of different sludge disintegration methods on sludge moisture distribution and dewatering performance

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Journal of Environmental Sciences 2015年第2期27卷 22-28页

作者： Lingyun Jin Guangming Zhang xiang zheng School of Environment & Resource Renmin University of China

A key step in sludge treatment is sludge dewatering. However, activated sludge is generally very difficult to be dewatered. Sludge dewatering performance is largely affected by the sludge moisture distribution. Sludge disintegration can destroy the sludge structure and cell wall, so as change the sludge floc structure and moisture distribution, thus affecting the dewatering performance of sludge. In this article, the disintegration methods were ultrasound treatment, K2 Fe O4oxidation and KMn O4 oxidation. The degree of disintegration（DDCOD）, sludge moisture distribution and the final water content of sludge cake after centrifuging were measured. Results showed that three disintegration methods were all effective, and K2 Fe O4oxidation was more efficient than KMn O4 oxidation. The content of free water increased obviously with K2 Fe O4and KMn O4 oxidations, while it decreased with ultrasound treatment. The changes of free water and interstitial water were in the opposite trend. The content of bounding water decreased with K2 Fe O4oxidation, and increased slightly with KMn O4 oxidation, while it increased obviously with ultrasound treatment. The water content of sludge cake after centrifuging decreased with K2 Fe O4oxidation, and did not changed with KMn O4 oxidation, but increased obviously with ultrasound treatment. In summary, ultrasound treatment deteriorated the sludge dewaterability, while K2 Fe O4and KMn O4 oxidation improved the sludge dewaterability.

关键词： Ultrasound treatment K2Fe O4oxidation KMn O4oxidation Sludge moisture distribution Dewatering performance

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Outage analysis of opportunistic multi-antenna relay selection in decode-and-forward relay networks

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The Journal of China Universities of Posts and Telecommunications 2010年第4期17卷 6-12页

作者： WANG Xiao-xiang zheng Zi-yun Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

This article studies the closed-form expressions of outage performance for opportunistic relay under aggregate power constraint in decode-and-forward （DF） relay networks over Rayleigh fading channels, assuming that multiple antennas are available at the relay node. According to whether instantaneous signal-to-noise ratio （SNR） or average SNR can be utilized for relay selection, two opportunistic relay schemes, opportunistic multi-antenna relay selection （OMRS） and average best relay selection （ABRS） are proposed. The performances of both two schemes are evaluated by means of theoretical analysis and simulation, it is observed that OMRS is outage-optimal among multi-antenna relay selection schemes and closely approaches the beamforming （BF） scheme known as theoretical outage-optimal. Compared with previous single-antenna opportunistic relaying （OR） scheme, OMRS brings remarkable performance improvement, which is obtained from maximum ratio combining （MRC） and beamforming techniques. It is also shown that the performance of ABRS in asymmetric channels is close to OMRS in the low and median SNR range.

关键词： relay selection multiple antennas multiple relays decode and forward cooperative networks

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Upconversion Nanoparticles-Encoded Hydrogel Microbeads-Based Multiplexed Protein Detection

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Nano-Micro Letters 2018年第2期10卷 135-150页

作者： Swati Shikha xiang zheng Yong Zhang Department of Biomedical Engineering Faculty of Engineering National University of Singapore (NUS) NUS Graduate School for Integrative Sciences and Engineering Centre for Life Sciences (CeLS)

Fluorescently encoded microbeads are in demand for multiplexed applications in different *** to organic dye-based commercially available Luminex's x MAP technology, upconversion nanoparticles(UCNPs) are better alternatives due to their large antiStokes shift, photostability, nil background, and single wavelength excitation. Here, we developed a new multiplexed detection system using UCNPs for encoding poly(ethylene glycol) diacrylate(PEGDA) microbeads as well as for labeling reporter antibody. However, to prepare UCNPs-encoded microbeads, currently used swellingbased encapsulation leads to non-uniformity, which is undesirable for fluorescence-based multiplexing. Hence,we utilized droplet microfluidics to obtain encoded microbeads of uniform size, shape, and UCNPs distribution inside. Additionally, PEGDA microbeads lack functionality for probe antibodies conjugation on their *** to functionalize the surface of PEGDA microbeads(acrylic acid incorporation, polydopamine coating)reported thus far quench the fluorescence of UCNPs. Here,PEGDA microbeads surface was coated with silica followed by carboxyl modification without compromising the fluorescence intensity of UCNPs. In this study, droplet microfluidics-assisted UCNPs-encoded microbeads of uniform shape, size, and fluorescence were *** color codes were generated by mixing UCNPs emitting red and green colors at different ratios prior to encapsulation. UCNPs emitting blue color were used to label the reporter antibody. Probe antibodies were covalently immobilized on red UCNPs-encoded microbeads for specific capture of human serum albumin(HSA) as a model protein. The system was also demonstrated for multiplexed detection of both human C-reactive protein(hCRP) and HSA protein by immobilizing anti-h CRP antibodies on green UCNPs.

关键词： Upconversion nanoparticles PEGDA microbeads Encoding Multiplexed bio-detection Single wavelength excitation

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A pilot scale anoxic/oxic membrane bioreactor(A/O MBR) for woolen mill dyeing wastewater treatment

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Journal of Environmental Sciences 2003年第4期15卷 449-455页

作者： zheng xiang FAN Yao bo WEI Yuan song Department of Water Pollution Control Technology Research Center for Eco Environmental SciencesChinese Academy of SciencesBeijing 100085China.

A pilot scale(10 m 3/d) anoxic/oxic membrane bioreactor(A/O MBR) was tested for dyeing wastewater treatment of woolen mill without wasting sludge in 125 days operation. Results showed that the effluent quality was excellent, i.e. effluent COD less than 25 mg/L, BOD 5 under 5 mg/L, turbidity lower than 0 65 NTU, and colour less than 30 DT, and met with the reuse water standard of China. The removal rates of COD, BOD 5, colour, and turbidity were 92 4%, 98 4%, 74% and 98 9%, respectively. Constant flux operation mode was carried out in this study, and backwash was effective for reducing membrane fouling and maintaining constant flux. Membrane fouling had heavy impact on energy consumption. More attention should be paid on pipe selection and design for the sidestream MBR system, too.

关键词： activated sludge backwash constant flux dyeing wastewater treatment membrane bioreactor (MBR) woolen mill

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Mechanical analysis and reasonable design for Ti-Al alloy liner wound with carbon fiber resin composite high pressure vessel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 384-391页

作者： Chuan-xiang zheng Fan YANG Ai-shi ZHU Chemical Process Machinery Institution Zhejiang University Hangzhou 310027 China School of Biological and Chemical Engineering Zhejiang University of Science and Technology Hangzhou 310012 China

To consider the internal pressure loaded by both the cylindrical Ti-Al alloy liner and the carbon fiber resin composite (CFRC) wound layers, two models are built. The first one is a cylinder loaded with the internal pressure in the hoop direction only. In this model, the total hoop direction load is distributed over all layers under the internal pressure. The second one is a cylinder loaded with the internal pressure in the axial direction only. In this model, the total axial load is distributed over all cylinders under the internal pressure. Taking the boundary conditions of the continuous displacement between layers into account, a group of equations are built. From these equations, we get the solutions of stresses in both hoop direction and axial direction loaded by every layer under internal pressures. After the stresses are obtained, a reasonable design can be done. An example is given in the final section of this study.

关键词： Mechanical analysis Composite Pressure vessel Models

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Reconciling the father tongue and mother tongue hypotheses in Indo-European populations

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National Science Review 2019年第2期6卷 293-300页

作者： Menghan Zhang Hong-xiang zheng Shi Yan Li Jin State Key Laboratory of Genetic Engineering and Collaborative Innovation Center for Genetics and Development School of Life SciencesFudan University Human Phenome Institute Fudan University Ministry of Education Key Laboratory of Contemporary Anthropology School of Life SciencesFudan University Chinese Academy of Sciences Key Laboratory of Computational Biology CAS-MPG Partner Institute for Computational Biology SIBS CAS

In opposition to the mother tongue hypothesis, the father tongue hypothesis states that humans tend to speak their fathers’ language, based on a stronger correlation of languages to paternal lineages(Y-chromosome) than to maternal lineages(mitochondria). To reassess these two competing hypotheses,we conducted a genetic–linguistic study of 34 modern Indo-European(IE) populations. In this study,genetic histories of paternal and maternal migrations in these IE populations were elucidated using phylogenetic networks of Y-chromosomal and mitochondrial DNA haplogroups, respectively. Unlike previous studies, we quantitatively characterized the languages based on lexical and phonemic systems separately. We showed that genetic and linguistic distances are significantly correlated with each other and that both are correlated with geographical distances among these populations. However, when controlling for geographical factors, only the correlation between the distances of paternal and lexical characteristics,and between those of maternal and phonemic characteristics, remained. These unbalanced correlations reconciled the two seemingly conflicting hypotheses.

关键词： Indo-European populations Y-chromosomal haplogroup mitochondrial DNA haplogroup lexical system phonemic system

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Pharmacokinetics and enterohepatic circulation of jervine,an antitumor steroidal alkaloid from Veratrum nigrum in rats

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Journal of Pharmaceutical Analysis 2019年第5期9卷 367-372页

作者： Bingjing zheng Caihong Wang Wenwen Song Xiaoxia Ye zheng xiang School of Pharmaceutical Sciences Wenzhou Medical University

Jervine,a novel steroidal alkaloid from Veratrum nigrum L.,exhibits both antitumor effect and potential *** aim of study was to characterize the pharmacokinetic behaviors and enterohepatic circulation of jervine in rats.A rapid and simple ultra-high performance liquid chromatography-tandem mass spectrometric method was developed and validated for quantification of jervine and alpinetin (internal standard) in rat *** extraction from rat plasma by a simple protein-precipitation method,the analyte was separated on a C18 column (2.1 mm×50 mm,1.7μm) using water with 0.1%formic acid and acetonitrile as the mobile phase delivered at a flow rate of 0.4mL/*** and alpinetin were determined in the positive mode with multiple reaction monitoring (MRM) of the ion transitions at m/z426.3→108.8 and m/z 271.0 166.9,*** docking method was used to investigate the binding of jervine to p-glycoprotein and dehydroepiandrosterone *** method was well validated within acceptance limits including specificity,matrix effect,recovery,precision,accuracy,and stability,and was successfully applied to the pharmacokinetic study of jervine after oral and intravenous administration to *** presented a small volume of distribution,fast absorption,high oral bioavailability,and enterohepatic *** enterohepatic circulation was first observed in veratrum alkaloids,and was further investigated by molecular docking studies,which was related to the binding of jervine to p-glycoprotein and dehydroepiandrosterone *** pharmacokinetic properties and enterohepatic circulation of jervine in rats provided a significant basis for the drug-drug interaction and toxicity study in the future.

关键词： Jervine UPLC-MS/MS Pharmacokinetics Enterohepatic circulation

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