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Real-time,single-particle chemical composition,volatility and mixing state measurements of urban aerosol particles in southwest China

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Journal of Environmental Sciences 2024年第2期136卷 361-371页

作者： Luyao Chen Junke Zhang Jiaqi Li Xiaojuan Huang Yuzheng xiang Jing Chen Tingru pan Wei Zhang Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China School of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China Sichuan Environmental Monitoring Center Chengdu 610074China

To investigate the volatility of atmospheric particulates and the evolution of other particulate properties(chemical composition,particle size distribution and mixing state)with temperature,a thermodenuder coupled with a single particle aerosol mass spectrometer was used to conduct continuous observations of atmospheric fine particles in Chengdu,southwest *** of their complex sources and secondary reaction processes,the average mass spectra of single particles contained a variety of chemical components(including organic,inorganic and metal species).When the temperature rose from room temperature to280℃,the relative areas of volatile and semi-volatile components decreased,while the relative areas of less or non-volatile components ***(>80%)nitrate and sulfate existed in the form of NH_(4)NO_(3)and(NH_(4))_(2)SO_(4),and their volatilization temperatures were50–100℃and 150–280℃,*** contribution of biomass burning(BB)and vehicle emission(VE)particles increased significantly at 280℃,which emphasized the important role of regional biomass burning and local motor vehicle emissions to the core of *** the increase in temperature,the particle size of the particles coated with volatile or semi-volatile components was reduced,and their mixing with secondary inorganic components was significantly *** formation of K-nitrate(KNO_(3))and K-sulfate(KSO_(4))particles was dominated by liquid-phase processes and photochemical reactions,*** KNO_(3)and BB particles is the key to improving *** new results are helpful towards better understanding the initial sources,pollution formation mechanisms and climatic effects of fine particulate matter in this megacity in southwest China.

关键词： Atmospheric fine particles TD-SPAMS Chemical composition Volatility Mixing state

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基于Radon变换的浅海宽带脉冲声源定位

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浙江大学学报（工学版） 2005年第9期39卷 1306-1309,1377页

作者：潘翔胡青浙江大学信息与通信工程研究所浙江杭州310027 杭州应用声学研究所浙江杭州310012

为了提高声纳在浅海的工作性能,在分析实验数据的基础上提出了新的多路径定位方法.将已知信号与每个通道的接收信号进行相关,获得相关系数矩阵,对由相关系数矩阵构成的图像进行Radon变换,以时间分辨力补偿空间分辨力,提取声场的多路径参... 详细信息

为了提高声纳在浅海的工作性能,在分析实验数据的基础上提出了新的多路径定位方法.将已知信号与每个通道的接收信号进行相关,获得相关系数矩阵,对由相关系数矩阵构成的图像进行Radon变换,以时间分辨力补偿空间分辨力,提取声场的多路径参数,估计声线到达角和到达时延差,结合声线反传技术,实现宽带脉冲声源定位.在修正阵型估计误差后,进一步提高算法的定位精度.实验结果表明,该方法能有效地对浅海脉冲声源进行定位,不受空间采样率或路径数必须小于阵元数的限制,具有较好的宽容性.算法计算量小,易于工程实现.

关键词： Radon变换多路径参数提取浅海源定位声纳

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水下沉底小目标回波的短时FrFT滤波分析

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浙江大学学报（工学版） 2008年第6期42卷 918-922页

作者：王强潘翔浙江大学信息与电子工程学系

为提高主动声纳在浅海区域探测水下沉底目标的能力,研究了二类水下沉底目标回波和混响的时频特性.基于分数阶傅里叶变换(FrFT)方法,设计高斯窗的短时FrFT算法(STFrFT)对水下沉底目标回波进行表征,根据回波和湖底混响在FrFT域的时频聚焦... 详细信息

为提高主动声纳在浅海区域探测水下沉底目标的能力,研究了二类水下沉底目标回波和混响的时频特性.基于分数阶傅里叶变换(FrFT)方法,设计高斯窗的短时FrFT算法(STFrFT)对水下沉底目标回波进行表征,根据回波和湖底混响在FrFT域的时频聚焦性差别,将最佳旋转后的信号进行u域窄带滤波可有效地抑制混响的干扰.湖试数据分析表明,在两类沉底目标探测过程中的短时FrFT时频面上湖底混响拖尾衰减较快,该方法可有效地提取回波中稳健的时频特征.

关键词：水声回波混响沉底目标短时分数阶傅里叶变换滤波

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Screening the effective components in treating dampness stagnancy due to spleen deficiency syndrome and elucidating the potential mechanism of Poria water extract

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Chinese Journal of Natural Medicines 2023年第2期21卷 83-98页

作者： LI Huijun ZHANG Dandan WANG Tianhe LUO Xinyao XIA Heyuan pan xiang HAN Sijie YOU Pengtao WEI Qiong LIU Dan ZOU Zhongmei YE Xiaochuan Hubei Key Laboratory of Resources and Chemistry of Chinese Medicine School of PharmacyHubei University of Chinese MedicineWuhan 430065China Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100193China

Poria is an important medicine for inducing diuresis to drain dampness from the middle ***,the specific effective components and the potential mechanism of Poria remain largely *** identify the effective components and the mechanism of Poria water extract(PWE)to treat dampness stagnancy due to spleen deficiency syndrome(DSSD),a rat model of DSSD was established through weight-loaded forced swimming,intragastric ice-water stimulation,humid living environment,and alternate-day fasting for 21 *** 14 days of treatment with PWE,the results indicated that PWE increased fecal moisture percentage,urine output,D-xylose level and weight;amylase,albumin,and total protein levels;and the swimming time of rats with DSSD to different *** highly related components were screened out using the spectrum-effect relationship and *** studies revealed that PWE significantly increased the expression of serum motilin(MTL),gastrin(GAS),ADCY5/6,p-PKAα/β/γcat,and phosphorylated cAMP-response element binding protein in the stomach,and AQP3 expression in the ***,it decreased the levels of serum ADH,the expression of AQP3 and AQP4 in the stomach,AQP1 and AQP3 in the duodenum,and AQP4 in the *** induced diuresis to drain dampness in rats with *** main effective components were identified in *** exerted therapeutic effect by regulating the AC-cAMP-AQP signaling pathway in the stomach,MTL and GAS levels in the serum,AQP1 and AQP3 expression in the duodenum,and AQP3 and AQP4 expression in the colon.

关键词： Poria water extract Dampness stagnancy due to spleen deficiency syndrome Spectrum-effect relationship Effective components Mechanisms

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Morphological Classification of Infrared Galaxies Based on WISE

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Research in Astronomy and Astrophysics 2024年第4期24卷 222-236页

作者： Zhi-Ren pan Bo Qiu Cui-xiang Liu A-Li Luo Xia Jiang Xiao-Yu Guo School of Electronic and Information Engineering Hebei University of TechnologyTianjin 300401China Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

This study introduces a novel convolutional neural network,the WISE Galaxy Classification Network(WGC),for classifying spiral and elliptical galaxies using Wide-field Infrared Survey Explorer(WISE)*** attains an accuracy of 89.03%,surpassing the combined use of K-means or SVM with the Color-Color method in more accurately identifying galaxy *** enhanced variant,WGC_mag,integrates magnitude parameters with image features,further boosting the accuracy to 89.89%.The research also delves into the criteria for galaxy classification,discovering that WGC primarily categorizes dust-rich images as elliptical galaxies,corresponding to their lower star formation rates,and classifies less dusty images as spiral *** paper explores the consistency and complementarity of WISE infrared images with SDSS optical images in galaxy morphology *** SDSS Galaxy Classification Network(SGC),trained on SDSS images,achieved an accuracy of 94.64%.The accuracy reached 99.30% when predictions from SGC and WGC were *** the complementarity of features in WISE and SDSS images,a novel variant of a classifier,namely the Multi-band Galaxy Morphology Integrated Classifier,has been *** classifier elevates the overall prediction accuracy to 95.39%.Lastly,the versatility of WGC was validated in other data *** the HyperLEDA data set,the distinction between elliptical galaxies and Sc,Scd and Sd spiral galaxies was most pronounced,achieving an accuracy of 90%,surpassing the classification results of the Galaxy Zoo 2 labeled WISE data *** research not only demonstrates the effectiveness of WISE images in galaxy morphology classification but also represents an attempt to integrate multi-band astronomical data to enhance understanding of galaxy structures and evolution.

关键词： methods:data analysis infrared:galaxies galaxies:spiral galaxies:elliptical and lenticular cD

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Aression of TLR_9 in human pulmonary adenocarcinoma cell line A549

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The Chinese-German Journal of Clinical Oncology 2009年第7期8卷 393-396页

作者： Jun Yu Tiecheng pan xiang Wei Ligang Liu Min Hu Fang Yuan Jiaduo Li Department of Cardiothoracic Surgery Tongji Hospital Tongji Medical College Huazhong University of Science andTechnology Wuahn 430030 China

Objective:Being considered as a bridge between the innate immunity and acquired immunity,Toll-like receptors(TRLs) are very important innate immunity *** researchs on the innate immunity have focused on the relationship between TLRs and human *** paper investgated the expression and significance of TLR9 in human pulmonary adenocarcinoma cell(A549 cell) and human bronchial epithelial cell(HBE cell).Methods:After culturing A549 cell and HBE cell in vitro,the expression of TLR9 mRNA and protein in both cells were detected by immunocytochemistry,Real-time Quantitative Reverse Transcriptase-Polymerase Chain Reaction(Real-time Quantitative PCR) and Western blot,***:By immunocytochemistry staining,TLR9 was mainly expressed in both cells' cell membrane and endochylema as brown-yellow *** showed that the expressions of TLR9 mRNA and protein in A549 cell were stronger than those in HBE cell(P < 0.01).Conclusion:The results suggest TLR9 might cause the progression of human pulmonary adenocarcinoma,and the mechanism needs to be further investgatied.

关键词： TLR9 A549 cell HBE cell immunocytochemistry Real-time Quantitative PCR western blot

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Triterpene Glycosides from Sea Cucumber Holothuria scabra with Cytotoxic Activity

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Chinese Herbal Medicines 2012年第3期4卷 183-188页

作者： Hua HAN[a][b] Ling LI[b] Yang-hua YI[b] Xiao-hua WANG[c] Min-xiang pan[d] College of Animal Sciences Zhejiang UniversityHangzhou 310058China Research Center for Marine Drugs School of PharmacySecond Military Medical UniversityShanghai 200433China

Objective To study the new triterpene glycosides from sea cucumber Holothuria scabra with cytotoxic activity. Methods Triterpene glycosides from H. scabra were separated and purified by chromatography on DA-101, silica gel, and reversed-phase silica gel column, as well as RP-HPLC. Their structures were elucidated on the basis of spectral data and chemical evidence. Results Three triterpene glycosides were identified as scabraside D (1), fuscocineroside C (2), and 24-dehydroechinoside A (3). Their inhibition on P-388, A549, MKN-28, HCT116, and MCF-7 cells were significant. Conclusion Scabraside D (1) is a new triterpene glycoside, and compounds 2 and 3 are isolated from H. scabra for the first time. The glycosides 1-3 show the in vitro cytotoxicity against five human tumor cell lines in comparison to 10-hydroxycamptothecin.

关键词： cytotoxicity 24-dehydroechinoside A fuscocineroside C Holothuria scabra scabraside D triterpene glycoside

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岩爆等级预测的Bayes判别模型及应用

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现代隧道技术 2017年第4期54卷 146-151页

作者：潘翔周口师范学院周口466001

文章将Bayes判别法应用到岩爆等级预测分析中,选择了围岩的最大切应力σθ、单轴抗压强度σc、单轴抗拉强度σt、应力系数σθ/σc、脆性系数σc/σt和弹性能量指数Wet作为基本指标,以108组岩爆实例作为研究对象建立Bayes判别模型。针对... 详细信息

文章将Bayes判别法应用到岩爆等级预测分析中,选择了围岩的最大切应力σθ、单轴抗压强度σc、单轴抗拉强度σt、应力系数σθ/σc、脆性系数σc/σt和弹性能量指数Wet作为基本指标,以108组岩爆实例作为研究对象建立Bayes判别模型。针对Bayes判别模型,提出了优势比概念并将其用于分析岩爆指标与岩爆等级之间的趋势性关系以及岩爆等级对指标的敏感性,在此基础上评价不同指标组合下的Bayes判别模型是否合理。分析结果表明:σθ/σc、Wet指标组合建立的Bayes判别模型是最合理的模型,其预测效果好,所得出的岩爆等级概率表达式可用于地下工程的岩爆等级预测。

关键词：岩爆预测敏感性 Bayes判别模型优势比

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A Bayesian approach to matched field processing in uncertain ocean environments

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Chinese Journal of Acoustics 2008年第4期27卷 358-367页

作者： LI Jianlong pan xiang Department of Information Science & Electronic Engineering Zhejiang University Hangzhou 310027

An approach of Bayesian Matched Field Processing （MFP） was discussed in the uncertain ocean environment. In this approach, uncertainty knowledge is modeled and spatial and temporal data received by the array are fully used. Therefore, a mechanism for MFP is found, which well combines model-based and data-driven methods of uncertain field processing. By theoretical derivation, simulation analysis and the validation of the experimental array data at sea, we find that （1） the basic components of Bayesian matched field processors are the cor- responding sets of Bartlett matched field processor, MVDR （minimum variance distortionless response） matched field processor, etc.; （2） Bayesian MVDR/Bartlett MFP are the weighted sum of the MVDR/Bartlett MFP, where the weighted coefficients are the values of the a posteriori probability; （3） with the uncertain ocean environment, Bayesian MFP can more correctly locate the source than MVDR MFP or Bartlett MFP; （4） Bayesian MFP can better suppress sidelobes of the ambiguity surfaces.

关键词： ocean environments matched field processing Matched Field Processing weighted coefficients weighted sum methods of sets of

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Degradation behaviors of Nabumetone and its metabolite during UV/monochloramine process:Experimental and theoretical study

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Journal of Environmental Sciences 2024年第8期142卷 103-114页

作者： xiang Tu Yunsong Bai Qing Fu Sheng Chang Kunfeng Zhang Yang pan Ruiyang Xiao Yifu Fu Qi Zhang State Key Laboratory of Environmental Criteria and Risk Assessment State Environmental Protection Key Laboratory of Drinking Water Source ProtectionResearch Centre of Lake EnvironmentNational Engineering Laboratory for Lake Pollution Control and Ecological RestorationChinese Research Academy of Environmental SciencesBeijing 100012China School of Environmental Science and Engineering Suzhou University of Science and TechnologySuzhou 215009China Institute of Environmental Engineering School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083China School of Forestry Northeast Forestry UniversityHarbin 150040China

This study investigated degradation behaviors of a nonsteroidal anti-inflammatory drug Nabumetone(NMT)and its major metabolite 6-methoxy-2-naphthylacetic acid(MNA)in the coupling process of ultraviolet and monochloramine(UV/NH2Cl).The second-order rate constants of the contaminants reacting with reactive radicals(HO·,Cl·,Cl_(2)·-,and CO_(3)·^(-))were determined by laser flash photolysis ***·and Cl·contributed predominantly with 52.3%and 21.7%for NMT degradation and 60.8%and 22.3%for MNA *** presence of chlorides retarded the degradation of NMT,while promoted the destruction of MNA,which was ascribed to the photosensitization effects of MNA under UV *** functional theory(DFT)calculations revealed that radical adduct formation(RAF)was dominant pathway for both HO·and Cl·reacting with the contaminants,and hydrogen atom transfer(HAT)preferred to occur on side chains of NMT and *** reacted with NO_(2)·through single electron transfer(SET)with the second-order rate constant calculated to be 5.35×10^(7)(mol/L)^(-1)sec^(-1),and the contribution of NO_(2)·was predicted to be 13.0%of the total rate constant of NMT in pure water,which indicated that NO_(2)·played a nonnegligible role in the degradation of *** acute toxicity and developmental toxicity of NMT were enhanced after UV/NH_(2)Cl treatment,while those of MNA were *** transformation products of both NMT and MNA exhibited higher mutagenicity than their parent *** study provides a deep understanding of the mechanism of radical degradation of NMT and MNA in the treatment of UV/NH2Cl.

关键词： UV/NH_(2)Cl Reactive species Degradation kinetics Reaction mechanism Degradation products

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