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Chinese Journal of Polymer Science 2007年第2期25卷 187-195页

作者： Wen-xi Cheng li-ya shi shi-yun li Hui Chen Tao Tang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

The possibility of mesoporous acid solid as a carder for metallocene catalyst in ethylene polymerization and catalyst for polyethylene （PE） catalytic degradation was investigated. Here, HMCM-41 and AIMCM-41, and mesoporous silicoaluminophosphate molecular sieves （SAPO1 and SAPO2） were synthesized and used as acid solid. Much more gases were produced during catalytic degradation in PE/acid solid mixtures via in situ polymerization than those via physical mixing. The particle size distribution results exhibited that the particle size of SAPO1 in the PE/SAPOI mixture via in situ polymerization was about 1/14 times of that of the original SAPO1 or SAPO1-supported metallocene catalyst. This work shows a novel technology for chemical recycling of polyolefin.

关键词： Catalytic degradation Acid solids Supported metallocene catalysts Polyethylene.

An on-line solid phase extraction-liquid chromatography tandem mass spectrometry method for the determination of perfluoroalkyl substances in the Antarctic ice core samples

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Chinese Chemical Letters 2015年第9期26卷 1073-1078页

作者： ya-li shi Yuan-Yuan Pan li-Na liang ya-Qi Cai State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental ScienceChinese Academy of Sciences Thermo Fisher Scientific(China)Co. Ltd.

An on-line solid phase extraction-high performance liquid chromatography-tandem mass spectrometry method for the analysis of perfluoroalkyl substances（PFASs） in water samples was *** optimal analytical conditions were obtained through the optimization of the extraction efficiency of online solid phase extraction column,sample loading rate and loading volume,and the concentration of ammonium acetate in mobile *** the optimal condition,the analytical method displayed good linearity（r^2〉0.99） for 12 PFASs（C5-C14 perfluoroalkyl carboxylic acids and C6/C8 perfluoroalkyl sulfonic acids） over a concentration range of 0.5-100 ng/*** limits of quantitation for samples were between 0.025 ng/L and 0.5 ng/L and the relative standard deviations（RSD） of five consecutive analyses were less than 10%for 1 ng/L standard *** results were obtained using this analytical method for the analysis of perfluoroalkyl substances in Antarctic ice core *** recoveries of all perfluoroalkyl substances were in a range of 73%-117%when the samples were spiked with standards at the concentrations of 2.5 ng/L and 25 ng/L.

关键词： Perfluoroalkyl substances On-line solid phase extraction LC-MS/MS Antarctic ice cores

Realization of an Automated Microassembly Task Involving Micro Adhesive Bonding

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International Journal of Automation and computing 2013年第6期10卷 545-551页

作者： Fu-Dong li De Xu Zheng-TaoZhang ya-li shi Research Center of Precision Sensing and Control Institute of AutomationChinese Academy of Sciences

An automated approach is proposed for a microassembly task, which is to insert a 10 μm diameter glass tube into a 12 μm diameter hole in a silicon substrate, and bond them together with ultraviolet （UV） curable adhesive. Two three-degree-of-freedom micromanipulators axe used to move the glass tube and the dispensing needle, respectively. Visual feedback is provided by an optical microscope. The angle of the microscope axis is precisely calibrated using an autofocus strategy. Robust image segmentation method and feature extraction algorithm are developed to obtain the features of the hole, the glass tube and the dispensing needle. Visual servo control is employed to achieve accurate aligning for the tube and the hole. Automated adhesive dispensing is used to bond the glass tube and the silicon substrate together after the insertion. On-line monitoring ensures that the diameter of the adhesive spot is within a desired range. Experimental results demonstrate the effectiveness of the proposed strategy.

关键词： Micro adhesive bonding microassembly visual servo control image segmentation feature extraction.

Perfluorinated compounds in blood of textile workers and barbers

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Chinese Chemical Letters 2014年第8期25卷 1145-1148页

作者： Cheng Lu ya-li shi Zhen Zhou Nan-Nan liu Zhao-Fu Meng ya-Qi Cai Department of Environmental Engineering College of Resource and Environment Northwest A & F University State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

12 perfluorinated compounds（PFCs） in human blood from workers in a textile mill in Shandong province and several barbershops in Tianjin were analyzed in this study. It was found that perfluorooctanesulfonate（PFOS） and perfluorooctanoate（PFOA） were the most prominent PFCs, with average concentrations of 5.73 mg/L and 5.46 mg/L for textile workers, and 2.55 mg/L and 2.84 mg/L for *** and perfluorohexanesulfonate（PFHxS） concentrations revealed a positive correlation in blood samples（p 〈 0.01）, and concentrations among PFOS, perfluorononanoic acid（PFNA） and perfluorodecanoic acid（PFDA） also revealed positive correlations（p 〈 0.01）. The influence of gender and age on PFC concentration in blood was also investigated, and the results showed that there was no statistically significant difference between the male and female samples, as well as in samples from people with different ages. Generally speaking, the textile workers

关键词： Perfluorinated compounds Blood Textile workers Barbers

New insights on serodiagnosis of trichinellosis during window period:early diagnostic antigens from Trichinella spiralis intestinal worms

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Infectious Diseases of Poverty 2017年第1期6卷 368-371页

作者： Zhong-Quan Wang ya-li shi Rou-Dan liu Peng Jiang ya-Yi Guan Ying-Dan Chen Jing Cui Department of Parasitology Medical CollegeZhengzhou UniversityZhengzhou 450052China National Institute of Parasitic Diseases Chinese Center for Disease Control and PreventionKey Laboratory of Parasite and Vector BiologyMinistry of HealthShanghai 200025China

The clinical diagnosis of trichinellosis is difficult because its clinical manifestations are *** of anti-Trichinella IgG by EliSA using *** muscle larval excretory-secretory(ES)antigens is the most commonly used serological method for diagnosis of trichinellosis,but the main disadvantage is false negativity during the early stage of *** is an obvious window period between Trichinella infection and antibody *** the intestinal stage of Trichinella infection,the ES antigens of intestinal worms(intestinal infective larvae and adults)are exposed to host’s immune system at the earliest time and elicit the production of specific anti-Trichinella ***-Trichinella IgG antibodies in infected mice were detectable by EliSA with ES antigens of intestinal worms as soon as 8-10 days post infection(dpi),but EliSA with muscle larval ES antigens did not permit detection of infected mice before 12 ***,the new early antigens from *** intestinal worms should be screened,identified and characterized for early serodiagnosis of trichinellosis.

关键词： Trichinellosis Early serodiagnosis Intestinal infective larvae Adult worms

The surface adsorption and micelle formation of the mixed aqueous solutions of fluorocarbon and hydrocarbon surfactants——Ⅱ.Sodium perfluorooctanoate-sodium decylsulfate system

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Acta Chimica Sinica(English Edition) 1984年第2期2卷 111-118页

作者： ZHAO Guo-Xi ZHU Bu-yao ZHOU ya-Ping shi li Department of Chemistry,Peking University Department of Chemistry Peking University

The adsorption and micellar behavior of the mixed solutions of sodium perfluorooctanoate（7CFNa）and sodium decylsulfate(C10SNa)have been studied at constant ion strength of *** ad-sorption wascalculated from the surface（and interfacial）tension-concentration curves by applying *** was found that the cmc’s of 7CFNa and C10SNa are of nearly the same value(1.66×10-2m and 1.45×10-2m,respectively),but γcmcof 7CFNa solution is～23 mNm-1,which is much lowerthan that of C10SNa *** implies that 7CFNa would have a much higher surface activitythan C10SNa and be adsorbed preferentially;for instance,7CFNa has a surface mole fraction ofabout 0.8 in the saturated adsorption layer of the 1:1 mixed *** mole fractions of7CFNa at the surface are always greater than those in the bulk *** adsorption at the n-heptane-aqueous solution interface is quite different from that at the air-solution ***10SNa is preferentially adsorbed owing to'Mutual phobicity'between the HC-chain of n-heptaneand the FC-chain of 7CFNa at the *** the cmc’s obtained from the γ-log m relations of7CFNa (or C10SNa)in the mixed solutions have nearly the same value and the cmc-x curves show apositive deviation from the ideal *** further indicates that in the mixed solutions of fluorocarbonand hydrocarbon surfactants no completely miscible micelle but essentially the individual micelle ofeach surfactant exist due to the'Mutual phobicity'between FC-and HC-chain in the micellizationprocess.

关键词： CF Sodium perfluorooctanoate-sodium decylsulfate system The surface adsorption and micelle formation of the mixed aqueous solutions of fluorocarbon and hydrocarbon surfactants

Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期68卷 233-240页

作者： Peipei liu yantong li Meng-Xiang Wu Hao Kang Xiao-li Zhao lin Xu linlin liu Xiaodong li Junfeng Fang Zhiwei Fang ya Cheng Hai-Bo yang Huakang Yu Xueliang shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction

Germacrane Sesquiterpene Esters from Salvia roborowskii

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有机化学 2003年第Z1期23卷 7-7页

作者： li ya shi yan-Ping li Yu National Laboratory of Applied Organic Chemistry Lanzhou University and Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 National Laboratory of Applied Organic Chemistry Lanzhou University and Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 National Laboratory of Applied Organic Chemistry Lanzhou University and Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000

　　Salvia roborowskii Maxim, usually called "ye zhi ma" by local inhabitants of northwestern China, an annual or biennial herb distributed widely in the west of China, has long been used as a traditional folk medicin... 详细信息

关键词： Salvia roborowskii in the west of China northwestern China

Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction

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Computers, Materials & Continua 2025年第1期82卷 1069-1086页

作者： shi li Didi Sun College of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant ***-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying *** comprehension is crucial for making informed strategic decisions in various business and societal ***,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause *** address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment *** model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause ***,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among *** proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 *** results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its *** research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-c

关键词： Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms

Interpretable Machine Learning Method for Compressive Strength Prediction and Analysis of Pure Fly Ash-based Geopolymer Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 65-78页

作者： shi Yuqiong li Jingyi ZHANG yang li li Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F Uni-versityYangling 712100China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China Chongqing Key Laboratory of Public Big Data Security Technology Chongqing 401420China Chongqing College of Mobile Communication Chongqing 401520China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityKowloonHung HomHong KongChina

In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive *** this study,505 groups of data were collected,and a new database of compressive strength of PFGC was *** order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative *** five machine learning models all showed good compressive strength prediction performance on *** them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,*** R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,*** two models have high prediction accuracy and outstanding generalization *** order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 *** 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide *** temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement *** importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.

关键词： machine learning pure fly ash geopolymer compressive strength feature perception