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Semi-interpenetrating-network all-solid-state polymer electrolyte with liquid crystal constructing efficient ion transport channels for flexible solid lithium-metal batteries 被引量:1
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作者 Qinghui Zeng Yu Lu +9 位作者 Pingping Chen zhenfeng li Xin Wen Wen Wen Yu liu Shuping Zhang Hailei Zhao Henghui Zhou Zhi-xiang Wang liaoyun Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第4期157-167,共11页
The development of the solid-state polymer electrolytes (SPEs) for Li-ion batteries (LIBs) can effectively address the hidden safety issues of commercially used liquid electrolytes.Nevertheless,the unsatisfactory room... The development of the solid-state polymer electrolytes (SPEs) for Li-ion batteries (LIBs) can effectively address the hidden safety issues of commercially used liquid electrolytes.Nevertheless,the unsatisfactory room temperature ion conductivity and inferior mechanical strength for linear PEO-based SPEs are still the immense obstacles impeding the further applications of SPEs for large-scale commercialization.Herein,we fabricate a series of semi-interpenetrating-network (semi-IPN) polymer electrolytes based on a novel liquid crystal (C6M LC) and poly(ethylene glycol) diglycidyl ether (PEGDE) via UV-irradiation at the first time.The LCs not only highly improve the mechanical properties of electrolyte membranes via the construction of network structure with PEGDE,but also create stable ion transport channels for ion conduction.As a result,a free-standing flexible SPE shows outstanding ionic conductivity(5.93×10^(-5) S cm^(-1) at 30℃),a very wide electrochemical stability window of 5.5 V,and excellent thermal stability at thermal decomposition temperatures above 360℃ as well as the capacity of suppressing lithium dendrite growth.Moreover,the LiFePO_(4)/Li battery assembled with the semi-IPN electrolyte membranes exhibits good cycle performance and admirable reversible specific capacity.This work highlights the obvious advantages of LCs applied to the electrolyte for the advanced solid lithium battery. 展开更多
关键词 Solid-state polymer electrolyte Liquid crystal Semi-interpenetrating-network Ion transport channels Lithium battery
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Optimization of Control Loops and Operating Parameters for Three-Phase Separators Used in Oilfield Central Processing Facilities
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作者 zhenfeng li Yaqiao li Guangjun Wei 《Fluid Dynamics & Materials Processing》 EI 2023年第3期635-649,共15页
In this study,the Stokes formula is used to analyze the separation effect of three-phase separators used in a Oilfield Central Processing Facility.The considered main influencing factors include(but are not limited to... In this study,the Stokes formula is used to analyze the separation effect of three-phase separators used in a Oilfield Central Processing Facility.The considered main influencing factors include(but are not limited to)the typical size of oil and water droplets,the residence time and temperature of fluid and the dosage of demulsifier.Using the“Specification for Oil and Gas Separators”as a basis,the control loops and operating parameters of each separator are optimized Considering the Halfaya Oilfield as a testbed,it is shown that the proposed approach can lead to good results in the production stage. 展开更多
关键词 Distributed control system(DCS) three-phase separator control loop operating parameter
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Clinical significance of S100A7 protein in predicting recurrence of breast cancer in patients undergoing breast-conserving surgery with radiotherapy
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作者 Chao Zhang Changyou li +6 位作者 Gaoyang lin Yao Qi zhenfeng li Jing Xu Tianhui Su Xin liu Xiao Zou 《Oncology and Translational Medicine》 2019年第5期211-217,共7页
Objective To investigate the relationship between the expression of S100A7 protein and prediction of recurrence and prognosis of breast cancer in patients undergoing breast-conserving surgery combined with radiotherap... Objective To investigate the relationship between the expression of S100A7 protein and prediction of recurrence and prognosis of breast cancer in patients undergoing breast-conserving surgery combined with radiotherapy.Methods 349 samples of carcinoma tissue wax blocks were selected from January 2011 to January 2014 in Qingdao Central Hospital.All the patients had undergone breast-conserving surgery.We analyzed S100A7 expression in tumor tissue by immunohistochemical staining.Using univariate and multivariate analyses,we evaluated the relationship between S100A7 and clinical results,to explore independent risk factors for local regional recurrence(LRR).Results The positive expression of S100A7 in the recurrence group(66.7%)was significantly higher than in the non-recurrence group(38.4%),P=0.025.A log-rank test showed that high S100A7 expression was significantly correlated with 5-year regional recurrence free survival rate(RFS)(94.9%vs 89.5%,P=0.0408),distant metastasis free survival rate(DFS)(95.4%vs 83.5%,P<0.001),and overall survival rate(OS)(99.0%vs 92.5%,P=0.0011).Histological grade,vessel carcinoma embolus,lymph node metastasis,S100A7 expression,and tumor size were factors that influenced RFS.Multivariate analysis of the Cox proportional hazard model showed that high S100A7 expression was an independent risk factor that affected breast cancer RFS(HR=6.864,95%CI:1.575-29.915,P=0.01).Thus,we concluded that high S100A7 expression is associated with increased risk of LRR and distant metastasis of breast cancer after breast-conserving surgery and postoperative radiotherapy.S100A7 can be used as a molecular marker to screen for patients with high recurrence risk after breast-conserving surgery. 展开更多
关键词 S100A7 BREAST-CONSERVING surgery RADIOTHERAPY LOCOREGIONAL RECURRENCE PROGNOSIS
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一种涡流静态混合器流动及混合特性 被引量:1
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作者 周逸凡 金光远 +7 位作者 吴松 景玉豪 朱正山 冯文凯 宋春芳 李臻峰 宋飞虎 李静 《过程工程学报》 北大核心 2025年第5期471-482,共12页
静态混合器无须外部能源、结构紧凑、集成便利,在食品加工行业中具有重要地位。其中涡流的引入能够显著提升其混合效率,提高反应效率及效果。目前主流涡流静态混合器通过内部结构产生涡流以达成高效混合,其结构需承受流动冲击,有损坏风... 静态混合器无须外部能源、结构紧凑、集成便利,在食品加工行业中具有重要地位。其中涡流的引入能够显著提升其混合效率,提高反应效率及效果。目前主流涡流静态混合器通过内部结构产生涡流以达成高效混合,其结构需承受流动冲击,有损坏风险。本工作研究了一种涡流静态混合器,并通过数值模拟方法研究其流动与混合特性,考察了入口流速及结构参数,包括腔室长径比(D/H)和轴向管径比(D/Da)的影响。结果表明,混合器内部以涡流为主,伴有显著二次流,包括二次涡循环流区、短路流区以及偏心涡区。提高入口流速增强了内部涡流流动,减弱了二次流,出口分离强度显著减小。当流速达0.223 m/s,可于腔室出口达到完全混合。减小D/H或增加D/Da可强化内部涡流流动,混合效果随D/H减小而增强,随D/H由6减小至4,涡流腔出口分离强度由4.03×10^(-3)减少至5.23×10^(-4)。 展开更多
关键词 混合 静态混合器 涡流管 计算流体力学 涡流 二次流
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基于数据融合策略的红茶发酵程度判别 被引量:8
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作者 张柏 凌彩金 +4 位作者 李露青 周巧仪 zhenfeng li 宋飞虎 宋春芳 《农业工程学报》 EI CAS CSCD 北大核心 2022年第15期339-347,共9页
发酵是红茶加工过程中关键的一道工序,对红茶的品质形成有着重要影响。该研究以大叶种英德红茶中的英红九号为研究对象,试验收集了204份不同发酵时间的红茶样品并使用便携式近红外光谱仪和工业相机获取红茶发酵中的信息,基于近红外光谱... 发酵是红茶加工过程中关键的一道工序,对红茶的品质形成有着重要影响。该研究以大叶种英德红茶中的英红九号为研究对象,试验收集了204份不同发酵时间的红茶样品并使用便携式近红外光谱仪和工业相机获取红茶发酵中的信息,基于近红外光谱数据、图像数据和数据融合策略分别建立了红茶发酵程度判别模型。通过分析茶多酚和儿茶素类含量的变化,将红茶的发酵划分为3个阶段,即发酵不足、发酵适度和发酵过度。采用Savitzky-Golay光滑对原始光谱进行预处理,利用竞争自适应重加权采样(Competitive Adaptive Reweighted Sampling,CARS)、连续投影算法(Successive Projections Algorithm,SPA)和主成分分析(Principal Components Analysis,PCA)对近红外光谱变量进行降维处理;相应地,图像进行去阴影后提取了9个颜色特征变量,采用皮尔森(Pearson)相关分析和主成分分析进行特征变量提取。最后采用线性判别分析(Linear Discriminant Analysis,LDA)和支持向量机(Support Vector Machine,SVM)分别建立了基于近红外、图像和两者数据融合的分类模型。结果表明,在建模数据相同的条件下,非线性的支持向量机模型性能优于线性判别分析模型。单一传感器数据建模效果不佳,近红外光谱和图像判别模型的预测集最大准确率仅为83.82%和73.53%。低层次数据融合建模效果较单一传感器数据建模无明显提升,而中层次的数据融合建模效果比单一数据建模均有显著提高,其中SPA提取光谱变量结合Pearson提取图像变量建立的判别模型效果较佳,校正集和预测集准确率分别达到了97.06%和95.59%。研究表明,近红外光谱和视觉结合的中层次融合策略可以作为一种快速判别红茶发酵程度的方法,研究结果为红茶发酵程度构建等级模型与判别奠定了一定的理论基础,为红茶发酵的自动化检测提供了重要依据。 展开更多
关键词 近红外光谱 机器视觉 红茶发酵 数据融合 判别模型
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A study of connectivity features analysis in brain function network for dementia recognition
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作者 Siying li Peng Wang +6 位作者 zhenfeng li lidong Du Xianxiang Chen Jie Sun libin Jiang Gang Cheng Zhen Fang 《Nanotechnology and Precision Engineering》 2025年第1期79-93,共15页
Dementias such as Alzheimer disease(AD)and mild cognitive impairment(MCI)lead to problems with memory,language,and daily activities resulting from damage to neurons in the brain.Given the irreversibility of this neuro... Dementias such as Alzheimer disease(AD)and mild cognitive impairment(MCI)lead to problems with memory,language,and daily activities resulting from damage to neurons in the brain.Given the irreversibility of this neuronal damage,it is crucial to find a biomarker to distinguish individuals with these diseases from healthy people.In this study,we construct a brain function network based on electroencephalography data to study changes in AD and MCI patients.Using a graph-theoretical approach,we examine connectivity features and explore their contributions to dementia recognition at edge,node,and network levels.We find that connectivity is reduced in AD and MCI patients compared with healthy controls.We also find that the edge-level features give the best performance when machine learning models are used to recognize dementia.The results of feature selection identify the top 50 ranked edge-level features constituting an optimal subset,which is mainly connected with the frontal nodes.A threshold analysis reveals that the performance of edge-level features is more sensitive to the threshold for the connection strength than that of node-and network-level features.In addition,edge-level features with a threshold of 0 provide the most effective dementia recognition.The K-nearest neighbors(KNN)machine learning model achieves the highest accuracy of 0.978 with the optimal subset when the threshold is 0.Visualization of edge-level features suggests that there are more long connections linking the frontal region with the occipital and parietal regions in AD and MCI patients compared with healthy controls.Our codes are publicly available at https://github.com/Debbie-85/eeg-connectivity. 展开更多
关键词 ELECTROENCEPHALOGRAPHY Brain function network Machine learning Feature selection Dementia recognition
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Detection and airflow obstruction severity grading of chronic obstructive pulmonary disease based on capnography
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作者 Xiuying Mou Peng Wang +7 位作者 Xianya Yu Jie Sun Xianxiang Chen lidong Du zhenfeng li Jingen Xia Xiaoran li Zhen Fang 《Nanotechnology and Precision Engineering》 2025年第3期98-108,共11页
Chronic obstructive pulmonary disease(COPD)is a major chronic disease with high global mortality,and capnography offers a noninvasive method for testing lungs function under natural breathing.Reported here is the best... Chronic obstructive pulmonary disease(COPD)is a major chronic disease with high global mortality,and capnography offers a noninvasive method for testing lungs function under natural breathing.Reported here is the best paradigm for COPD diagnosis and airflow obstruction severity assessment based on capnography as achieved by comparing the performance of five machine learning methods.In this study,1007 subjects underwent capnography and pulmonary function tests,then segment-fitted capnography was used to extract quantitative features.Using a hybrid scoring strategy to identify the head features,XGBoost performed the best,with accuracy,precision,recall,and F1 score of 90.08%,90.33%,90.08%,and 89.72%,respectively.This work shows for the first time the feasibility of using capnography to evaluate ventilation dysfunction in COPD patients.The proposed XGBoost-based method offers support to clinicians for assessing patients’ventilatory function by capnography,which has considerable potential as an alternative to traditional pulmonary function tests for respiratory diseases. 展开更多
关键词 CAPNOGRAPHY COPD Ventilatory dysfunction assessment Machine learning
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Monitoring black tea fermentation quality by intelligent sensors: Comparison of image, e-nose and data fusion 被引量:5
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作者 Qiaoyi Zhou Zhenhua Dai +3 位作者 Feihu Song zhenfeng li Chunfang Song Caijin ling 《Food Bioscience》 SCIE 2023年第2期947-958,共12页
To scientifically and objectively monitor the fermentation quality of black tea,a computer vision system(CVS)and electronic nose(e-nose)were employed to analyze the black tea image and odor eigenvalues of Yinghong No.... To scientifically and objectively monitor the fermentation quality of black tea,a computer vision system(CVS)and electronic nose(e-nose)were employed to analyze the black tea image and odor eigenvalues of Yinghong No.9 black tea.First,the variation trends of tea polyphenols,volatile substances,image eigenvalues and odor eigenvalues with the extension of fermentation time were analyzed,and the fermentation process was categorized into three stages for classification.Second,principal component analysis(PCA)was employed on the image and odor eigenvalues obtained by CVS and e-nose.Partial least squares discriminant analysis(PLS-DA)was performed on 117 volatile components,and 51 differential volatiles were screened out based on variable importance in projection(VIP≥1)and one-way analysis of variance(P<0.05),including geraniol,linalool,nerolidol,and α-ionone.Then,image features and odor features are fused by using a data fusion strategy.Finally,the image,smell and fusion information were combined with random forest(RF),K-nearest neighbor(KNN)and support vector machine(SVM)to establish the classification models of different fermentation stages and to compare them.The results show that the feature-level fusion strategy integrating the SVM was the most efficient approach,with classification accuracy rates of 100%for the training sets and 95.6%for the testing sets.The performance of Support Vector Regression(SVR)prediction models for tea polyphenol content based on feature-level fusion data outperformed data-level models(Rc,RMSEC,Rp and RMSEP of 0.96,0.48 mg/g,0.94,0.6 mg/g). 展开更多
关键词 Computer vision Electronic nose(e-nose) Data fusion strategy Black tea fermentation
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Enhancing Li-ion conduction and mechanical properties via addition of fluorine-containing metal–organic frameworks in allsolid-state cross-linked hyperbranched polymer electrolytes 被引量:1
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作者 Wen Wen Qinghui Zeng +7 位作者 Pingping Chen Xin Wen zhenfeng li Yu liu Jiazhu Guan Anqi Chen Wei liu liaoyun Zhang 《Nano Research》 SCIE EI CSCD 2022年第10期8946-8954,共9页
Poly(ethylene oxide)(PEO)-based solid polymer electrolytes(SPEs)are commonly used in lithium metal batteries(LMBs)for their good Li-salt solvating ability and easy processability.However,the relatively low Li-ion cond... Poly(ethylene oxide)(PEO)-based solid polymer electrolytes(SPEs)are commonly used in lithium metal batteries(LMBs)for their good Li-salt solvating ability and easy processability.However,the relatively low Li-ion conduction ability hinders their further development.In this work,a novel hyperbranched-polyether-type composite solid polymer electrolyte(CSPE)is prepared via a quick cross-linking reaction between aldehyde-terminated polyethylene glycol(PEG)and hyperbranched poly(ethylene imine)(HPEI)in the presence of lithium salt and fluorine-containing Zr-based metal–organic framework(MOF)UiO-66-(F)_(4).The hydrogen bonds between the fluorine atoms and amino groups in the electrolyte help to the better dispersion of UiO-66-(F)_(4) in the polymer matrix,which is beneficial to solving the problem of aggregation of nanofillers.Besides,the CSPEs with the functional MOF fillers show improvements in both electrochemical and mechanical properties.Notably,the Li-ion transference number(t)is considerably enhanced from 0.23 to 0.54.All-solid-state LMBs based on the CSPE also present good cycling performances.A high specific discharge capacity of 141.4 mAh·g^(−1) is remained after 200 cycles at 0.2 C.This study not only provides an effective synthesis method of the cross-linked hyperbranched polymer electrolyte,but also puts forward a new strategy for uniform dispersion of inorganic fillers in CSPEs. 展开更多
关键词 hyperbranched cross-linked polymer electrolyte ALL-SOLID-STATE metal-organic frameworks composite lithium metal batteries
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Intelligent control for quality improvement in green tea fixation assisted with aroma detection 被引量:1
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作者 Feihu Song Xiaohu Jia +1 位作者 zhenfeng li Chunfang Song 《Food Bioscience》 SCIE 2023年第3期2939-2951,共13页
An intelligent control system is designed in green tea fixation,which can automatically and continuously adjust the fixation parameters for quality improvement.Aroma is detected with PEN-3 electronic nose,and signals ... An intelligent control system is designed in green tea fixation,which can automatically and continuously adjust the fixation parameters for quality improvement.Aroma is detected with PEN-3 electronic nose,and signals are sent to the computer.With the aroma signals,the fixation process is separated into two stages:in the first stage,the key purpose is enzymatic reaction,which can be suppressed with high temperature;it is the oxidation re-action which should be concentrated on in the second stage,and a middle temperature is a good choice.With the designed fuzzy logic algorithm,the pot temperature is kept at a high level at the beginning,and the enzymatic reaction can be successfully reduced.In the second stage,the temperature is kept at a middle value to decrease oxidation.With the designed intelligent control,the green tea product quality is improved for aroma,taste,appearance,liquor color,and residues. 展开更多
关键词 Intelligent control Green tea fixation Fuzzy algorithm Aroma detection
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