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Journal of Environmental Sciences 2014年第8期26卷 1681-1688页

作者： yulu tian Hongjun Liu Qixiang Wang Jian Zhou Xuexi Tang College of Marine Life Sciences Ocean University of China Marine Biology Institute of Shangdong Province

Perinereis aibuhitensis was used to assess adverse biological effects caused by acute and chronic Pb2＋exposure in artificial seawater under controlled laboratory conditions. In 96-hr acute toxicity experiments,the morphological changes showed a positive time/dose-dependent tendency,and the 96-hr LC50 value of Pb2＋was 686.41 mg/L. The responses of enzymatic and non-enzymatic antioxidants in tissues including catalase（CAT）,peroxidase（POD）,superoxide dismutase（SOD）,glutathione peroxidase（GSH-PX）,malondialdehyde（MDA） and the content of total soluble protein（TSP）,were investigated on days 1,4,7 and 10 after Pb2＋exposure under chronic toxicity testing. Results showed that the activation of the antioxidant system in P. aibuhitensis depended on the Pb2＋concentration and the duration of exposure ***,POD and SOD activities were induced on the first day of the exposure and decreased to the control level on day 10 after exposure. Therefore,these two indexes could be used to indicate oxidative stress associated with P. aibuhitensis exposure to Pb2＋.

关键词： Perinereis aibuhitensis Toxicity Antioxidant system Pb2+

Assessment of gully erosion susceptibility using different DEM-derived topographic factors in the black soil region of Northeast China

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International Soil and Water Conservation Research 2023年第1期11卷 97-111页

作者： Donghao Huang Lin Su Lili Zhou yulu tian Haoming Fan College of Water Conservancy Shenyang Agricultural UniversityShenyang110866China College of Forestry Shenyang Agricultural UniversityShenyang110866China Key Laboratory of Soil Erosion Control and Ecological Restoration in Liaoning ProvinceShenyang110866China College of Urban and Environmental Sciences Northwest UniversityXi'an710127China

As a primary sediment source,gully erosion leads to severe land degradation and poses a threat to food and ecological ***,identification of susceptible areas is critical to the prevention and control of gully *** study aimed to identify areas prone to gully erosion using four machine learning methods with derived topographic *** topographic attributes(elevation,slope aspect,slope degree,catchment area,plan curvature,profile curvature,stream power index,and topo-graphic wetness index)were derived as feature variables controlling gully occurrence from digital elevation models with four different pixel sizes(5.0 m,12.5 m,20.0 m,and 30.0 m).A gully inventory map of a small agricultural catchment in Heilongjiang,China,was prepared through a combination of field surveys and satellite *** topographic attribute dataset was randomly divided into two portions of 70%and 30%for calibrating and validating four machine learning methods,namely random forest(RF),support vector machines(SVM),artificial neural network(ANN),and generalized linear models(GLM).Accuracy(ACC),area under the receiver operating characteristic curve(AUC),root mean square error(RMSE),and mean absolute error(MAE)were calculated to assess the performance of the four machine learning methods in predicting spatial distribution of gully erosion susceptibility(GES).The results suggested that the selected topographic attributes were capable of predicting GES in the study catchment area.A pixel size of 20.0 m was optimal for all four machine learning *** RF method described the spatial relationship between the feature variables and gully occurrence with the greatest accuracy,as it returned the highest values of ACC(0.917)and AUC(0.905)at a 20.0 m *** RF was also the least sensitive to resolutions,followed by SVM(ACC=0.781-0.891,AUC=0.724-0.861)and ANN(ACC=0.744-0.808,AUC=0.649-0.847).GLM performed poorly in this study(ACC=0.693-0.757,AUC=0.608-0.703).Ba

关键词： Gully erosion Machine learningmethods Topographicattribute Pixel size Northeast China

Robust Frequency Estimation Under Additive Symmetric α-Stable Gaussian Mixture Noise

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Intelligent Automation & Soft Computing 2023年第4期36卷 83-95页

作者： Peng Wang yulu tian Bolong Men Hailong Song Beijing Orient Institute of Measurement and Test Beijing10083China University of Science&Technology Beijing Beijing10083China

Here the estimating problem of a single sinusoidal signal in the additive symmetricα-stable Gaussian(ASαSG)noise is *** ASαSG noise here is expressed as the additive of a Gaussian noise and a symmetricα-stable distributed *** the probability density function(PDF)of the ASαSG is complicated,traditional estimators cannot provide optimum *** on the Metropolis-Hastings(M-H)sampling scheme,a robust frequency estimator is proposed for ASαSG ***,to accelerate the convergence rate of the developed algorithm,a new criterion of reconstructing the proposal covar-iance is derived,whose main idea is updating the proposal variance using several previous samples drawn in each *** approximation PDF of the ASαSG noise,which is referred to the weighted sum of a Voigt function and a Gaussian PDF,is also employed to reduce the computational *** computer simulations show that the performance of our method is better than the maximum likelihood and the lp-norm estimators.

关键词： Additive symmetricα-stable Gaussian mixture metropolis-hastings algorithm robust frequency estimation probability density function approximation

Robust Frequency Estimation Under Additive Mixture Noise

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Computers, Materials & Continua 2022年第7期72卷 1671-1684页

作者： Yuan Chen yulu tian Dingfan Zhang Longting Huang Jingxin Xu School of Computer and Communication Engineering University of Science&Technology BeijingBeijing100083China School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China School of Information Engineering Wuhan University of TechnologyWuhan430070China Department of Energy and Public Works Queensland4702Australia

In many applications such as multiuser radar communications and astrophysical imaging processing,the encountered noise is usually described by the finite sum ofα-stable(1≤α<2)*** this paper,a new parameter estimator is developed,in the presence of this new heavy-tailed *** the closed-formPDF of theα-stable variable does not exist exceptα=1 andα=2,we take the sum of the Cauchy(α=1)and Gaussian(α=2)noise as an example,namely,additive Cauchy-Gaussian(ACG)*** probability density function(PDF)of the mixed random variable,can be calculated by the convolution of the Cauchy’s PDF and Gaussian’s *** of the complicated integral in the PDF expression of the ACG noise,traditional estimators,e.g.,maximum likelihood,are analytically not *** obtain the optimal estimates,a new robust frequency estimator is devised by employing the Metropolis-Hastings(M-H)***,to guarantee the fast convergence of the M-H chain,a new proposal covariance criterion is also devised,where the batch of previous samples are utilized to iteratively update the proposal covariance in each sampling *** simulations are carried out to indicate the superiority of the developed scheme,when compared with several conventional estimators and the Cramér-Rao lower bound.

关键词： Frequency estimation additive cauchy-gaussian noise voigt profile metropolis-hastings algorithm cramér-rao lower bound

Cenozoic potassic volcanic rocks from the Keluo and Wudalianchi volcanic districts,northeast China:origin from the new sub-continental lithospheric mantle(SCLM)metasomatized by potassium-rich fluids from delaminated lower crust

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Frontiers of Earth Science 2022年第4期16卷 989-1004页

作者： Fanchao MENG yulu tian Yaoqi ZHOU Jiaqi LIU Gengchao ZUO Qing DU School of Geosciences China University of Petroleum(East China)Qingdao 266580China Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao 266061China Shandong Provincial Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

A series of Cenozoic potassium-rich volcanic rocks developed in the Xiaoguli-Keluo-Wudalianchi-Erkeshan districts,northeast *** source region and potassium-rich mechanism of the potassic rocks remain highly *** this paper,the major elements,trace elements,and Sr-Nd-Pb isotopes of the volcanic rocks in Keluo(KL)and Wudalianchi(WDLC)volcanic districts were analyzed *** results show that the volcanic rocks are characterized by high K2O(4.36wt.%-6.13wt.%),remarkable enrichment in LREEs and LILEs,as well as the strong fractionation of *** isotopic characteristics with high 87Sr/86Sr(0.704990-0.705272),low 143Nd/144Nd(0.512306-0.512417),low 206Pb/204Pb(16.546-17.135)and 207Pb/204Pb(15.002-15.783)of the volcanic rocks suggest the involvement of EM-I-type *** the basis of the geochemical characteristics,the potassium-rich volcanic magma originated from the new SCLM forming after delamination of the ancient SCLM,with metasomatism of the potassium-rich fluids released from the ancient lower crust during the Late *** proposed genetic model assumes the source which represented by a phlogopite-bearing garnet peridotite(with modal garnet in the range of 2%-10%)experienced very low degrees(i.e.,~0.5)of partial *** Cenozoic,the lithosphere in northeast China was affected by the extension and decompression of continental rift,and the metasomatized SCLM underwent low degree partial melting,resulting in the formation of potassium-rich primitive basaltic magma.

关键词： northeast China Keluo-Wudalianchi volcanic districts Cenozoic potassic volcanic rocks petrogenesis sub-continental lithospheric mantle

Mutations in EZH2 are associated with poor prognosis for patients with myeloid neoplasms

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Genes & Diseases 2019年第3期6卷 276-281页

作者： Qi Zhang Qi Han Jie Zi Jinlong Ma Huihui Song yulu tian Mary McGrath Chunhua Song Zheng Ge Department of Hematology Zhongda Hospital Southeast UniversityInstitute of Hematology Southeast UniversityNanjing 210009China Department of Pediatrics Pennsylvania State University College of MedicineHersheyPA 17033USA

EZH2 is a component of the polycomb repressive complex 2(PRC2),which is a highly conserved histone methyltransferase that methylates lysine 27 of histone ***2 mutations are associated with oncogenesis and progression of ***,the relationship between the clinical outcome of patients with myeloid malignancies and EZH2 mutations is ***,we performed a meta-analysis of 8 studies(n Z 2243 patients)that evaluates the correlation between EZH2 mutations and overall survival(OS)in patients with myeloid ***2 mutations were associated with significantly worse OS(hazard ratio[HR]Z 2.37,95%confidential interval(CI),1.48e3.79).In a word,EZH2 mutations indicate a poor prognosis for patients with myeloid neoplasms.

关键词： EZH2 Meta-analysis Mutations Myeloid neoplasms Prognostic

Enhancing the crystallinity and stability of perovskite solar cells with 4-tert-butylpyridine induction for efficiency exceeding 24%

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Journal of Energy Chemistry 2024年第6期93卷 1-7,I0001页

作者： You Liu Lishuang Zheng Kuanxiang Zhang Kun Xu Weicheng Xie Jue Zhang yulu tian tianyuan Liu Hanzhong Xu Ruoming Ma Wei Huang Jiahui Chen Jusheng Bao Chen Chen Yongsheng Zhou Xuchun Wang Junming Chen Jungan Wang College of Chemistry and Materials Engineering Anhui Science and Technology UniversityBengbu 233000AnhuiChina Anhui Province Quartz Sand Purification and Photovoltaic Glass Engineering Research Center Chuzhou 233100AnhuiChina Triumph Photovoltaic Materials Co.Ltd BengbuAnhuiChina National Laboratory of Solid State Microstructures School of PhysicsNanjing UniversityNanjing 210009JiangsuChina JinkoSolar Holding Co.Ltd HainingZhejiangChina

Perovskite solar cells(PSCs)have emerged as a promising photovoltaic technology because of their high light absorption coefficient,long carrier diffusion distance,and tunable ***,PSCs face challenges such as hysteresis effects and stability *** this study,we introduced a novel approach to improve film crystallization by leveraging 4-tert-butylpyridine(TBP)molecules,thereby enhancing the performance and stability of *** findings demonstrate the effective removal of PbI_(2)from the perovskite surface through strong coordination with TBP ***,by carefully adjusting the concentration of the TBP solution,we achieved enhanced film crystallinity without disrupting the perovskite *** TBP-treated perovskite films exhibit a low defect density,improved crystallinity,and improved carrier *** a result,the PSCs manufactured with TBP treatment achieve power conversion efficiency(PCE)exceeding 24%.Moreover,we obtained the PCE of 21.39%for the 12.25 cm^(2)module.

关键词： 4-tert-butylpyridine Film crystallization Perovskite solar cells Power conversion efficiency Stability improvement

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常益长高速铁路本跨线列车开行模式设计

铁道运营技术 2024年第1期30卷 1-4页

作者：田宇璐湖南铁路科技职业技术学院湖南株洲412000

以常益长高速铁路为研究对象,为提升沿线旅客服务质量需对列车开行模式进行设计。针对沿线既有线列车存在的开行频率低、通达范围小、运行时间长等问题,提出常益长高速铁路适合采用本线及跨线列车结合的列车开行模式,采用多要素分析法,... 详细信息

以常益长高速铁路为研究对象,为提升沿线旅客服务质量需对列车开行模式进行设计。针对沿线既有线列车存在的开行频率低、通达范围小、运行时间长等问题,提出常益长高速铁路适合采用本线及跨线列车结合的列车开行模式,采用多要素分析法,对拟开行的本线及跨线列车起讫点、列车等级、列车编组、列车开行频率等要素进行设计,确保列车开行模式能够适应旅客出行需求,为列车开行方案和运行图的合理编制奠定基础。

关键词：常益长高速铁路本跨线列车开行模式

杨绳武《文章鼻祖》与早期钟山书院的文学教育

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理论界 2022年第9期 72-79页

作者：田雨露复旦大学中国语言文学系

《文章鼻祖》作为钟山书院教材,是乾隆书院理念、早期钟山书院教育思想与杨绳武学术思想共同作用的产物。杨绳武选文经传、史汉、诗赋并重,所选皆为“文字之祖”,特别推尊《尚书·尧典》作为万事万物之祖的至高地位,建构了《尧典》与经... 详细信息

《文章鼻祖》作为钟山书院教材,是乾隆书院理念、早期钟山书院教育思想与杨绳武学术思想共同作用的产物。杨绳武选文经传、史汉、诗赋并重,所选皆为“文字之祖”,特别推尊《尚书·尧典》作为万事万物之祖的至高地位,建构了《尧典》与经传、史书、文章的渊源脉络。在具体阐释上,杨绳武采用以文说经的方法,抉发经传、史书的文学特征与价值,与乾隆以后经史研究方法异趋,体现出以文学为本位的教育理念,有为科举写作服务的现实意图。

关键词：杨绳武文章鼻祖钟山书院文学教育科举

维普期刊数据库博看期刊

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泡沫排水用起泡剂的应用进展

油田化学 2021年第2期38卷 368-373页

作者：田雨露王纪伟李加玉中国石化石油勘探开发研究院北京102206 中国石化重庆涪陵页岩气勘探开发有限公司重庆408014

气井起泡剂排水是提高单井产量的一项重要措施,也是国内外各大气田常用且经济可行的重要方法之一。经国内外文献调研,分析了起泡剂作用机理,综述了各类型常用起泡剂的应用进展及优缺点;介绍了耐温型、抗盐型、耐酸碱型、抗H2S类型、抗... 详细信息

气井起泡剂排水是提高单井产量的一项重要措施,也是国内外各大气田常用且经济可行的重要方法之一。经国内外文献调研,分析了起泡剂作用机理,综述了各类型常用起泡剂的应用进展及优缺点;介绍了耐温型、抗盐型、耐酸碱型、抗H2S类型、抗凝析油等新型起泡剂的研究进展;分析了起泡剂在制备与矿场应用过程中存在的问题,并提出了未来起泡剂的发展趋势。参50。

关键词：起泡剂排水机理发展趋势综述