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Science China Chemistry 2010年第11期53卷 2363-2372页

作者： Ling Kong ZhongFang Liu xiaoli hu ShaoPu Liu Southwest Univ Sch Chem & Chem Engn Minist Educ Key Lab Luminescence & Real Time Anal Chongqing 400715 Peoples R China

In a weak acidic medium(pH 2.4-2.8),eosin Y molecules(H2L) could replace water molecules to associate with Triton X-100 to form hydrophobic hydrogen bonding *** complexes could further aggregate to form nanoparticles through the squeezing action of the water phase and Van Der Waals force,resulting in changes in the absorption spectrum and fluorescence quenching of EY as well as the significant enhancement of resonance Rayleigh *** enables the sensitive determination of Triton X-100 using the fading spectrophotometry,fluorescence quenching method and RRS *** them,the RRS method shows the highest sensitivity with a detection limit of 20.6 ng mL-1 for Triton *** optimum experimental conditions and factors that affect the absorption,fluorescence and RRS spectra were *** effects of coexisting substances were investigated and the results showed good *** on these results,new spectrophotometric methods,fluorescence quenching method and RRS method for the determination of Triton X-100,were *** hydrogen bonding association of eosin Y with Triton X-100 and the formation of nanoparticles as well as their effects on related spectral characteristics were discussed utilizing infrared,transmission electron microscope technique and quantum chemical method.

关键词： eosin Y Triton X-100 resonance Rayleigh scattering fluorescence quenching absorption spectrum

Impact of land use change on water resource allocation in the middle reaches of the Heihe River Basin in northwestern China

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Journal of Arid Land 2014年第3期6卷 273-286页

作者： YanYun NIAN Xin LI Jian ZHOU xiaoli hu Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences College of Earth and Environmental Sciences Lanzhou University

In recent decades, China has been experiencing rapid economic development, population growth and urbanization. These processes have stressed the shortages of water resources in China, especially in the arid re- gions of northwestern China. In order to sustain the expanding cropland, people increased groundwater exploitation in these regions. The purpose of this study was to quantitatively analyze the changes in land use and water resources, and their relationship in the middle reaches of the Heihe River Basin, a typical inland river basin in northwest China. The data of land use change were interpreted using aerial photographs （1965） and Landsat TM images （1986 and 2007）. The data of irrigation water volume in the irrigation districts were spatialized in the middle reaches of the Heihe River Basin. The spatial variation of the groundwater depth was interpolated using the geo- statistical method. The results showed that the cultivated cropland area along oasis fringe increased by 15.38% and 43.60% during the periods 1965-1986 and 1986-2007, respectively. Surface water amount for irrigation had almost doubled from 1956 to 2010. The decrease of grassland area mainly occurred at the alluvial fan in front of the Qilian Mountains, with 36.47% during 1965-1986 and 38.56% during 1986-2007, respectively. The groundwater depth in front of the mountain constantly increased from 1986 to 2007. We found that the overuse of surface water and overexploitation of groundwater had direct consequences on the natural environments. We suggests that the efficiency of surface water resources use among different irrigation distdcts needs to be improved, which will significantly ease the conflicts between increasing water demand for irrigation and a shortage of water resources in the middle reaches of the Heihe River Basin.

关键词： watershed management land use groundwater irrigation arid region Heihe River Basin

基于VMD和Bat-KELM的仿真变电站蓄电池剩余寿命预测

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电源学报 2024年第4期22卷 251-259页

作者：任罡季宁胡晓丽李世倩张洁华吴祎国网江苏省电力有限公司技能培训中心苏州215004 南京邮电大学自动化学院南京210023 南京邮电大学人工智能学院南京210023 中国电源学会

仿真变电站蓄电池的工作模式呈现间歇非连续性,导致电池性能在退化过程中存在容量再生现象,退化规律具有非平稳性和随机性,增大了蓄电池精确剩余寿命RUL(remaining useful life)的难度。针对存在容量再生现象的蓄电池剩余寿命预测问题,... 详细信息

仿真变电站蓄电池的工作模式呈现间歇非连续性,导致电池性能在退化过程中存在容量再生现象,退化规律具有非平稳性和随机性,增大了蓄电池精确剩余寿命RUL(remaining useful life)的难度。针对存在容量再生现象的蓄电池剩余寿命预测问题,提出了变分模态分解VMD(variational mode decomposition)和蝙蝠(Bat)优化核极限学习机KELM(kernel extreme learning machine)组合的预测方法。基于VMD将蓄电池健康状态SOH(state of health)时间序列分解为整体退化分量和容量再生分量;利用Bat优化KELM构建各分量预测模型,以提高分量趋势预测精度;通过各分量独立预测结果的叠加,得到精确的蓄电池健康状态及剩余寿命预测值。将该方法应用于蓄电池退化数据实例分析中,结果表明该方法相较于KELM模型及VMD-KELM模型,预测精度更高,验证了该方法的优越性。

关键词：仿真变电站蓄电池剩余寿命预测变分模态分解核极限学习机

基于增强语言表示模型的网络新闻长文本分类的研究

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江汉大学学报（自然科学版） 2024年第4期52卷 37-44页

作者：许楠桸柯圆圆胡晓莉江汉大学人工智能学院湖北武汉430056

基于网络实时新闻内容数据,对一份具有时效的中文长文本数据集进行了新闻主题分类。利用年度关键词增强的分词方案提升分词精度,采用一种长文本压缩方法处理中文长文本的特殊数据,具体方法为选择关键句并利用TF-IDF算法提取长文本中关键... 详细信息

基于网络实时新闻内容数据,对一份具有时效的中文长文本数据集进行了新闻主题分类。利用年度关键词增强的分词方案提升分词精度,采用一种长文本压缩方法处理中文长文本的特殊数据,具体方法为选择关键句并利用TF-IDF算法提取长文本中关键词,再将组合的新文本进行词向量训练。最后,采用增强的语言表示模型进行新闻主题分类,并与6种机器学习和深度学习模型进行对比评估,评价指标为召回率、准确率、精度和F1分数等。实验结果表明:本文的模型可通过提取16个重要词对实时新闻长文本进行有效的分类。

关键词： ERNIE模型预训练模型新闻分类长文本处理中文文本

超微血流联合剪切波弹性成像技术对慢性肾脏病患者分期诊断的意义

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贵州医科大学学报 2024年第8期49卷 1212-1217页

作者：李硕刘婷刘晓明胡小丽贵州医科大学附属医院超声中心贵州贵阳550004 贵州医科大学医学影像学院贵州贵阳550004

目的探讨超微血流成像技术(SMI)及剪切波弹性成像技术(SWE)在慢性肾脏病(CKD)分期诊断中的应用价值。方法87例CKD患者分为早期(1~2期,n=42)组和晚期(3~5期,n=45),收集2组CKD患者入院时的一般临床资料[性别、年龄及体质量指数(BMI)]、相... 详细信息

目的探讨超微血流成像技术(SMI)及剪切波弹性成像技术(SWE)在慢性肾脏病(CKD)分期诊断中的应用价值。方法87例CKD患者分为早期(1~2期,n=42)组和晚期(3~5期,n=45),收集2组CKD患者入院时的一般临床资料[性别、年龄及体质量指数(BMI)]、相关实验室检查指标[肾小球滤过率(GFR)、血清肌酐(Scr)、尿素氮(BUN)及胱抑素C(cystatin-C)],采用彩色多普勒超声诊断仪行SMI及SWE检测,记录2组CKD患者肾脏大小轮廓、肾皮质厚度及回声、肾脏皮质血流充盈分级及杨氏模量值,采用ROC曲线评估SMI和SWE单独及联合检测对CKD分期的诊断效能。结果晚期组CKD患者血流分级、杨氏模量值水平高于CKD早期组,差异均有统计学意义(P<0.05);CKD患者杨氏模量值、血流分级分别与GFR呈负相关(P<0.001);SMI、SWE及联合超声技术在CKD不同分期下的诊断效能以2者联合曲线下面积(AUC)最高(0.71)。结论SMI及SWE联合检测对CKD患者分期诊断具有重要应用价值。

关键词：肾小球滤过率慢性肾脏病剪切波弹性成像超微血流成像杨氏模量值实验室检查

Formation and tribology properties of polyfluoroal-kylmethacrylate film on the magnetic head surface

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Chinese Science Bulletin 2005年第20期50卷 2385-2390页

作者： hu xiaoli ZHANG Chenhui LUO Jianbin WEN Shizhu State Key Laboratory of Tribology Tsinghua University Beijing 100084China

A polyfluoroalkylmethacrylate (PFAM) film has been coated on the surface of the magnetic head by a dipping coating method to modify the surface properties. The films were characterized by means of a time-of-flight secon- dary ion mass spectrometer (TOF-SIMS), contact angle measurement and atomic force microscopy (AFM). The re- sults indicate that the concentration of the solution is the main factor affecting the thickness, contact angle and surface topography of the film. The magnetic head with the PFAM film at a concentration of 500 ppm exhibits the best tribology properties, and the stiction between the magnetic head and the disk is no more than 2.4 g after 20000 contact start stop (CSS) cycles. Therefore, a fully covered PFAM film with few defects helps improve the tribology properties of the mag- netic head, and decrease the adsorbed contaminant on the magnetic head surface.

关键词：摩擦学聚乙烯薄膜形态学分光计

Ca-P Conversion Coating on AZ60 Magnesium Alloy for Biomedical Application

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Chemical Research in Chinese Universities 2014年第4期30卷 543-548页

作者： CHENG Zhongji LIAN Jianshe hu xiaoli YANG Xiaohong LI Guangyu Key Laboratory of Automobile Materials Ministry of Education College of Materials Science and Engineering Jilin University Changchun 130022 P. R. China

To improve the anti-corrosion behaviors of magnesium alloy in the inner environment of human body,a bioactive Ca-P coating was deposited on the AZ60 magnesium alloy by a novel simple *** morphologies of the Ca-P coatings formed under different treatment time were studied by scanning electron microscopy（SEM）.The corrosion behaviors of Ca-P coating were investigated by electrochemical polarization test and electrochemical impedance spectroscopy in both 3％（mass fraction） NaCl solution and simulated body fluid（SBF）.Immersion test in SBF was performed to evaluate the corrosion rate of Ca-P coated magnesium alloy.X-Ray diffraction（XRD） analysis result shows that the coating mentioned above mainly consists of dicalcium phosphate dehydrate（CaHPO4·2H2O,DCPD） and β-tricalcium phosphate dehydrate[β-TCP,Ca3（PO4）2],which exhibits good corrosion *** magnesium alloy was immersed in 1 mol/L NaOH solution at 80 ℃ for 2 h,hydroxyapatite [Ca10（PO4）6（OH）2,HA]appeared on the magnesium alloy substrate,which can further decrease the corrosion rate of AZ60 magnesium alloy in SBF.

关键词： Ca-P coating Deposited method Magnesium alloy Corrosion rate Simulated body fluid(SBF)

Special characteristics of fluorescence and resonance Rayleigh scattering for cadmium telluride nanocrystal aqueous solution and its interactions with aminoglycoside antibiotics

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Science China Chemistry 2009年第1期52卷 76-85页

作者： LI TaiShan LIU ShaoPu LIU ZhongFang hu xiaoli ZHANG LiPing School of Chemistry and Chemical Engineering Southwest UniversityChongqing 400715China Tangshan Environmental Monitoring Center Tangshan 063000China Hebei Energy Institute of Vocation and Technology Tangshan 063000China

CdTe nanocrystals(CdTe NCs) were achieved by reaction of CdCl2 with KHTe solution and were capped with sodium *** product was detected by transmission electron microscopy(TEM),high-resolution transmission electron microscopy(HRTEM),energy dispersive spectroscopy(EDS),fluorescence spectra,ultraviolet-visible spectra and X-ray diffraction(XRD).The CdTe NCs are of cubic structure and the average size is about 5 *** fluorescence quantum yield of CdTe NCs aqueous solution increased from 37% to 97% after 20 d under room *** maximum λem of fluorescence changed from 543 nm to 510 nm and the blue shift was 33 *** NCs aqueous solution can be steady for at least 10 months at 4℃ in a *** resonance Rayleigh scattering(RRS) of CdTe NCs in the aqueous solution was *** maximum scattering peak was located at about 554 *** interactions of CdTe NCs with amikacin sulfate(AS) and micronomicin sulfate(MS) were investigated *** effects of AS and MS on fluorescence and RRS of CdTe NCs were *** was found that AS and MS quenched the photoluminescence of CdTe NCs and enhanced RRS of CdTe *** optimum conditions,there are linear relationships between quenching intensity(F0-F),intensity of RRS(I-I0) and concentration of AS and *** detection limits(3б) of AS and MS are respectively 3.4 ng·mL-1 and 2.6 ng·mL-1 by the fluorescence quenching method,and 15.2 ng·mL-1 and 14.0 ng·mL-1 by the RRS *** methods have high sensitivity,thus CdTe NCs may be used as fluorescence probes and RRS probes for the detection of aminoglycoside antibiotics.

关键词： CdTe nanocrystal fluorescence characteristics resonance Rayleigh scattering amikacin sulfate micronomicin sulfate

Absorption, fluorescence and resonance Rayleigh scattering spectral characteristics of interaction of gold nanoparticle with safranine T

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Science China Chemistry 2005年第3期48卷 216-226页

作者： HE Youqiu LIU Shaopu LIU Qin LIU Zhongfang hu xiaoli Chemistry and Chemical Engineering College Southwest China Normal University Chongqing 400715 China Chemistry and Chemical Engineering College Southwest China Normal University Chongqing 400715 China Chemistry and Chemical Engineering College Southwest China Normal University Chongqing 400715 China Chemistry and Chemical Engineering College Southwest China Normal University Chongqing 400715 China Chemistry and Chemical Engineering College Southwest China Normal University Chongqing 400715 China

The interaction between gold nanoparticle and safranine T (ST) has been studied with resonance Rayleigh scattering (RRS) spectra, absorption and fluorescence spectra. In the pH 5 solution, citrate [(H2L)2?] self-assembles on the surface of positively-charged gold nanopar-ticle, which results in the [(Au)n(H2L)m]x? complex. In other words, one of carboxylate oxygens in (H2L)2? moves inward and combines with gold nanoparticle. The other carboxylate oxygens moves outward to form a supermolecular complex anion with x negative charges. Then by virtue of electrostatic attraction, hydrophobic force and charge transfer action, the complex anion binds with ST cation to form a new ion-association complex. Here (H2L)2? acts as a bridge. The forma-tion of the complex results in the significant enhancement of RRS intensity, the appearance of new RRS spectrum, the red shift of plasma absorption band of gold nanoparticle as well as the decrease in the absorbance and fluorescence quenching for safranine T. In this work, the inter-action between gold nanoparticle and ST on the RRS, absorption and fluorescence spectra has been investigated. The reason why RRS intensity increases greatly and the reaction mechanism have been inquired. The results show that RRS spectra can not only be used to study nanopar-ticle and reaction product, but also are a sensitive means to characterize and detect nanoparti-cles.

关键词： gold nanoparticle, resonance Rayleigh scattering spectra, fluorescence quenching, absorption spectra, safranine T.

Chromosomal localization of the major ribosomal RNA genes in scallop Chlamys farreri

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Acta Oceanologica Sinica 2006年第3期25卷 108-115页

作者： huANG Xiaoting BAO Zhenmin BI Ke hu Jingjie ZHANG Can ZHANG Quanqi hu xiaoli Laboratory of Marine Genetics and Breedings Division of Life Science and Technology Ocean University of China Qingdao 266003 China

The chromosomes of Chlamys farreri were analyzed by means of silver staining and fluorescence in situ hybridization （FISH） with 18S-28S rDNA probe. Probe was made by PCR amplification of a DNA fragment containing internal transcribed spacers ITS1 between 18S and 5.8S ribosomal RNA gene, ITS2 between 5.8S and 28S ribosomal RNA gene and 5.8S rRNA gene, and labeled by PCR incorporation of bio-16-dUTP. FISH signals were located on the short arm of subtelocentrie chromosome 10. After silverstaining, nucleolus organizer regions （NORs） could be observed on the telomere of the short arm of chromosome 10. However, one metaphase spread displayed an additional silver spot on the short arm of subtelocentrie chromosome 12.

关键词： rDNA Ag-NORs FISH Chlamysfarreri