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Journal of Harbin Institute of Technology(New Series) 2006年第5期13卷 549-553页

作者：何小青李攻科罗美中张展霞 shenzhen academy of metrology and quality inspection Shenzhen 518055 China Dept. of Chemistry Zhongshan University Guangzhou 510275 China

A new and simple microwave-assisted alkaline degradation （MAAD） method for the elimination of organoehlorine-pesticide interference on the determination of polychlorinated biphenyls （PCBs） in soil by GC is presented. Under the optimal conditions, the interference of α- HCH, β- HCH, γ -HCH,δ -HCH, o. p＇ - DDT, p. p＇ - DDD and p. p＇ - DDT could be eliminated completely, and p. p＇ - DDE, Aldrin and Dieldrin could be partially eliminated; however, Dieldrin could be completely eliminated by using concentrated sulphurie acid. The method was evaluated by analyzing the spiked-soil sample. The mean recovery obtained was 84. 1% and the Relative Standard Deviation （RSD） was 2. 7%. Experimental results also indicate that the degradation of the interference and the extraction of the target analytes, PCBs, could be carried out simuhaneously. Compared with the traditional methods, the MAAD method is a rapid, efficient and solvent-saving method,

关键词： microwave-assisted alkaline degradation (MAAD-) organochlorine pesticides (()Ps) polychlori-nated biphenyls (PCBs) : gas chromatography (GC)

Automated retinal layer segmentation on optical coherence tomography image by combination of structure interpolation and lateral mean filtering

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Journal of Innovative Optical Health Sciences 2021年第1期4卷 112-122页

作者： Yushu Ma Yingzhe Gao Zhaolin Li Ang Li Yi Wang Jian Liu Yao Yu Wenbo Shi Zhenhe Ma School of Computer Science and Engineering Northeastern University Shenyang 110169P.R.China shenzhen academy of metrology&quality inspection Shenzhen 518055P.R.China School of Control Engineering Northeastern University at Qinhuangdao Qinhuangdao 066004P.R.China

Segmentation of layers in retinal images obtained by optical coherence tomography(OCT)has become an important clinical tool to diagnose ophthalmic ***,due to the sus-ceptibility to speckle noise and shadow of blood vessels etc.,the layer segmentation technology based on a single image still fail to reach a satisfactory *** propose a combination method of structure interpolation and lateral mean filtering(SI-LMF)to improve the signal-to-noise ratio based on one retinal *** performing one-dimensional lateral mean filtering to remove noise,structure interpolation was operated to eliminate thickness ***,we used boundary growth method to identify *** with existing segmentations,the method proposed in this paper requires less data and avoids the influence of *** automatic segmentation method was verified on the spectral domain OCT volume images obtained from four normal objects,which successfully identified the boundaries of 10 physio-logical layers,consistent with the results based on the manual determination.

关键词： Optical coherence tomography retinal layers automatic segmentation mean filtering

Swelling properties and molecular simulation of PNIPA porous hydrogels

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Journal of Central South University 2013年第5期20卷 1161-1172页

作者：李智慧刘文涛李中原段翔远高旭静李蕴才杨明成何素芹朱诚身 School of Materials Science and Engineering Zhengzhou University shenzhen academy of metrology & quality inspection Key Laboratory for Special Functional Materials of Ministry of Education(Henan University) Isotope Institute of Henan academy of Sciences

A series of porous intelligent hydrogels, which exhibited appropriate lower critical solution temperature (LCST) and fast response behavior, were synthesized by radiation method. The structure and surface morphology of hydrogels were examined by the infrared radiation and the scanning electron microscopy, respectively. The influences of the content of crosslinking agent and relative molecular mass of polyethylene glycol (PEG) on the swelling properties of hydrogels were discussed. The molecular mechanics simulations were performed to investigate the phase transformation mechanism of poly(N-isopropyl acrylamide) (PNIPA) hydrogel. The results show that macropores are observed in hydrogels, whereas hydrogels prepared without using PEG have a dense surface. LCST of hydrogels increases with the increase of relative molecular mass of PEG. The swelling mechanism of PNIPA porous hydrogels follows non-Fickian diffusion model. The theoretical maximum water absorption S∞ is approximately consistent with experimental value according to the second-order kinetics model established by Schott. The molecule chains of PNIPA hydrogel begin folding and curling, resulting in volume shrinkage at 305 K. There are much intramolecular nonbonding interactions in molecule chains of hydrogels. The porous hydrogels are expected to be applied in the field of artificial intelligence material.

关键词： poly(N-isopropyl acrylamide) radiation swelling properties molecular simulation

Electrolyte Effect on Photoetching of Gallium Nitride

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Nanomanufacturing and metrology 2024年第1期7卷 61-74页

作者： Huiqiang Liang Zhenghao Wei Jiongchong Fang Yanming Li Changli Li Zhirun Xie Yun Hau Ng Guosong Zeng shenzhen Key Laboratory of Intelligent Robotics and Flexible Manufacturing Systems Southern University of Science and TechnologyShenzhen 518055People’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China School of Materials Sun Yat-Sen UniversityGuangzhou 510275People’s Republic of China School of Energy and Environment City University of Hong KongKowloon 999077Hong Kong SARPeople’s Republic of China City University of Hong Kong shenzhen Research Institute Shenzhen Hi-Tech Industrial ParkNanshan DistrictShenzhen 518000People’s Republic of China SUSTech Energy Institute for Carbon Neutrality Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

The limited material removal rate of conventional chemical mechanical polishing(CMP)significantly hinders the fabrica-tion efficiency and surface quality,thereby preventing the development of gallium nitride(GaN)-based ***,the incorporation of photoelectrochemistry in CMP has garnered increasing attention because of its potential to enhance the quality and efficiency of the GaN ***,a considerable gap still exists in the comprehensive understanding of the specific photoelectrochemical(PEC)behavior of ***,we report the influence of the electrolyte on the PEC etching of *** acids and bases were tested,with their pH being carefully *** concentrations of the cations and anions were also *** results showed that photocorrosion/photoetching was more pronounced in sulfuric acid,phosphoric acid,and nitric acid environments than in alkaline environments,but it was less pronounced in hydrochloric ***,the effects of pH and anion concentration on photoetching were investigated,and the results revealed that pho-toetching in acidic environments weakened with increasing pH levels and diminished with increasing sulfate *** underlying reasons contributing to this observation were *** findings provide ideas for improving the pho-toetching efficiency of GaN,thereby enriching the photoelectrochemical mechanical polishing(PECMP)technology of GaN.

关键词： GaN Photoelectrochemistry Photoetching pH

SpikeGoogle:Spiking Neural Networks with GoogLeNet-like inception module

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CAAI Transactions on Intelligence Technology 2022年第3期7卷 492-502页

作者： Xuan Wang Minghong Zhong Hoiyuen Cheng Junjie Xie Yingchu Zhou Jun Ren Mengyuan Liu School of Intelligent Systems Engineering Sun Yat-sen UniversityShenzhenChinaGuangdong Provincial Key Laboratory of Fire Science and Intelligent Emergency TechnologyGuangzhouChina shenzhen academy of metrology and quality inspection ShenzhenChina Infocare Systems Limited New Zealand

Spiking Neural Network is known as the third-generation artificial neural network whose development has great *** the help of Spike Layer Error Reassignment in Time for error back-propagation,this work presents a new network called SpikeGoogle,which is implemented with GoogLeNet-like inception *** this inception module,different convolution kernels and max-pooling layer are included to capture deep features across diverse *** results on small NMNIST dataset verify the results of the authors’proposed SpikeGoogle,which outperforms the previous Spiking Convolutional Neural Network method by a large margin.

关键词： GoogLeNet inception Spiking Neural Networks

Development of a Detection Method for Assaying Calf Intestine Alkaline Phosphatase Activity

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Animal Husbandry and Feed Science 2015年第3期7卷 152-155,166页

作者： Lin Lin Lai Xiaofang Li Yi Liu Yixiong Lan Quanxue Lai Xintian Yang Guowu shenzhen academy of metrology & quality inspection

[ Objective] This study was to develop a detection method for assaying calf intestine alkaline phasphatase activity in scientific research. [ Method ] By simulating the conditions and buffers for assaying calf intestine alkaline phosphatase used in the scientific research, the parameters influencing substmte concentration, reaction duration, eoloration time and buffer pH were optimized. [ Result] The activity of alkaline phosphatase detected varied hugely among different buffers, and potassium ferricyanide solution added with boracic acid achieved the stable coloration. The optimal water bath time was determined as 10 rain, and the substrate concentration was optimized as 0.04 moL/L. The increasing temperature did not have a large influence on low temperature enzymatic activity while did on high coneentration enzymatic activity. When the buffer pH was 7.0 - 8.0, the detection stability of alkaline phosphatase could be maintained well The ion intensity of buff- er had little effects on alkaline phasphatase activity. [ Conclusion] A detection method for assaying calf intestine alkaline phosphatase activity in scientific research was successfully developed in this study.

关键词： Alkaline phosphatase Calf intestine Activity detection Ultraviolet spectrophotomctry Scientific research

Cell Growth and Desorption on the Surface of Temperature-sensitive Semi-IPNs Hydrogels Based on Silk Sericin

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Journal of Wuhan University of Technology(Materials Science) 2012年第5期27卷 907-910页

作者：李学伟陈莉 State Key Laboratory of Hollow Fiber Membrane Materials and Processes School of Materials Science and EngineeringTianjinPolytechnic University Chongqing academy of metrology and quality inspection

Semi-interpenetrating （semi-IPNs） hydrogels containing biocompatible silk sericin （SS） and poly（N-isopropylacrylamide）（PNIPAM） were prepared as novel cellular matrices. Their maximum swelling degree and basic characteristics for biomedical applications such as mouse ？broblasts （L929） cell proliferation and desorption were investigated. The results showed that the incorporation of high hydrophilic SS into PNIPAM hydrogel increased the maximum swelling degree of the semi-IPNs hydrogels, and the adhesion and growth of the L929 on semi-IPNs hydrogels were at least comparable to, or even better than, that on conventional PNIPAM hydrogel. In addition, L929 cells were found to detach from the hydrogels surface naturally by controlling environmental temperature. These results suggest great potential of semi-IPNs hydrogels in tissue engineering.

关键词： semi-interpenetrating hydrogel biocompatible silk sericin N-isopropylacrylamide

fMRI-constrained source analysis of visual P300 in Landolt ring task

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Chinese Science Bulletin 2008年第1期53卷 76-86页

作者： LI YueZhi XU Tao WANG LiQun HU Yong College of Mechatronics and Control Engineering Shenzhen University Shenzhen 518060 China academy of metrology and quality inspection of-shenzhen Shenzhen518055 China Applied Superconductivity Reseamh Laboratory Tokyo Denki University Chiba Japan Department of Orthopaedics and Traumatology University of Hong Kong Hong Kong China

An fMRI-constrained source analysis was applied to investigate visual P300 in the Landolt ring task. To study the localization and relative activation timing of P300 generators, we implemented simultaneous EEG/fMRI to identify BOLD signal changes and record 64-channel EEG in 10 subjects during a Landolt ring task inside a 1.5-T fMRI scanner using an MR-compatible EEG recording system. MRI artifact sub-traction software was applied to obtain continuous EEG data. Then, the simultaneous collecting of EEG and fMRI was validated in preserving relevant ERPs. The fMRI-constrained source analysis resulted in an 8-dipole solution. The bilateral middle frontal and the right inferior parietal dipole waveforms showed a short latency peak corresponding to the early P300 activity, while the four parietal and the anterior cingulate dipole waveforms showed a long latency peak corresponding to the late P300 activity. The longest latency peak of the anterior cingulate dipole agrees with its role in initiation of motor re-sponse after successful target recognition. Target detection in the Landolt ring task produces the strongest and most extensive parietal activation (especially superior parietal activation), which might be due to its particular visual attention switching.

关键词：视觉共点流环 fMRI分析偶极子

Yellow-Fluorescence Carbon Dots Employed for pH Sensing and Detection of Tigecycline

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Chinese Journal of Chemistry 2023年第24期41卷 3677-3683页

作者： Jingwen Zhao Junchen Wang Linggao Zeng Sen Zhou Xiaoming Yang College of Pharmaceutical Sciences Southwest UniversityChongqing400715 China Chongqing academy of metrology and quality inspection Chongqing401121 China NMPA Key Laboratory for quality Monitoring of Narcotic Drugs and Psychotropic Substances Chongqing Institute for Food and Drug ControlChongqing401121 China

Long-wavelength fluorescence carbon dots (CDs) show great importance in multiple fields,especially for the biochemical ***,we proposed one type of CDs doped with nitrogen and sulfur through the hydrothermal method,which exhibited obvious yellow-fluorescence in aqueous ***,the fluorescence intensity of CDs decreased with pH decreasing in the acidic range,thus a linear relationship between pH and fluorescence intensity was established,exhibiting the potential of pH ***,introducing tigecycline into CDs resulted in their decreased fluorescence,thus,we further established a strategy of detecting tigecycline with the concentration range of 200 μM to 7 ***,we elucidated the static quenching as the major mechanism for CDs responding tigecycline,which was induced by the formed new complex between CDs and ***,the practicality of the method was verified by examining the recovery of tigecycline in the actual lake-water samples.

关键词： Yellow-fluorescence Tigecycline Nanostructures Quantum dots Sensors

Preparation of microencapsulatedα-olefin drag reducing polymer used in oil pipeline transportation

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Petroleum Science 2011年第1期8卷 99-107页

作者： Li Bing Xing Wenguo Dong Guilin Chen Xiangjun Zhou Ningning Qin Zhanbo Zhang Changqiao School of Chemistry and Chemical Engineering Shandong UniversityShandong 250061China Linyi Institute of Product quality Supervision and inspection Shandong 276004China Shandong Institute of metrology Shandong 250014China Shandong quality Certification Centre Shandong 250014China

Microcapsules containing oil drag-reducing polymer particles were prepared by melting-scattering and condensing of polyethylene wax,in-situ polymerization of urea and formaldehyde,and interfacial polymerization of styrene *** related processes were studied by a molecular dynamics simulation method,and molecular design of microcapsule isolation agent was carried out on the basis of the *** technologies for preparing microencapsulated oil drag-reducing polymer particles were compared and the circulation drag reducing efficiency of the microencapsulated polymer particles was evaluated based on the characterization results and their dissolution *** design of a microcapsule isolation agent suggests that a-olefin polymer particles can be stably dispersed in water by using long-chain alkyl sodium salt surfactant which can prevent the agglomeration ofα-olefin polymer *** results of simulation of the adsorption process shows that the amount of alkyl sodium salt surfactant can directly affect the stability of microencapsulatedα-olefin polymer particles, and there must be a minimum critical amount of *** characterization of the morphology by Scanning Electron Microscopy（SEM） and comparison of the static pressure stability,especially the conditions of reaction and technological control of microcapsules with different shell materials,microencapsulation of a-olefin polymer particles with poly-（urea-formaldehyde） as shell material was selected as the optimum scheme,because it can react under mild conditions and its technological process can be controlled in a large *** relationship of drag reducing rate and dissolving time of microcapsules showed that the formation of microcapsules did not affect the maximum drag reducing rate,and the drag reducing rate of each sample can reach about 35%along with the dissolving time,*** did not affect the drag reducing property ofα-olefin polymer.

关键词： α-olefin polymer molecular design coating material microcapsule preparation stability and solubility drag reducing property