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distribution and contamination status of chromium in surface sediments of northern Kaohsiung Harbor, Taiwan

Journal of Environmental Sciences 2013年第7期25卷 1450-1457页

作者： Cheng-di dong Chiu-Wen Chen Chih-Feng Chen Department of Marine Environmental Engineering "National" Kaohsiung Marine University

Thedistribution, enrichment, accumulation, and potential ecological risk of chromium （Cr） in the surface sediments of northern Kaohsiung Harbor, Taiwan, Chinawere investigated. Sediment samples from ten locations located between the river mouths and harbor entrance of northern Kaohsiung Harborwere collected quarterly in 2011 and characterized for Cr, aluminum,water content, organic matter, total nitrogen, total phosphorous, total grease, and grain size. Results showed that the Cr concentrations varied from 27.0 to361.9 mg/kgwith an average of （113.5 ± 87.0） mg/kg. High Cr concentrationwas observed near the Jen-Gen River mouth. The mean Cr concentrationwas high at 255.5 mg/kg,whichwas at least 2 to 7 times than that of other sites. This might imply significant Cr contribution from upstream receiving tannerieswastewater into the Jen-Gen River. The spatialdistribution of Cr reveals relatively high in the river mouth region, especially in Jen-Gen River, and graduallydiminishes toward the harbor entrance region. This indicates that the major sources of Cr pollution from upstream industrial and municipalwastewatersdischarged along the river bank; and Cr maydriftwith sea current and bedispersed into open sea. Moreover, Cr concentrations correlated closely to the physical-chemical properties of the sediments,which suggested the influence of industrial and municipalwastewatersdischarged from the neighboring industrial parks and river basins. Results from the enrichment factor andgeo-accumulation index analyses imply that the Jen-Gen River sediments can be characterized as moderate enrichment and none to medium accumulation of Cr, respectively. However, results of potential ecological risk index indicate that the sediment has low ecological potential risk. The results can provide valuable information todeveloping future strategies for the management of river mouth and harbor.

关键词： accumulation chromium ecological risk enrichment sediment

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Merging daily sea surface temperature data from multiple satellites using a Bayesian maximum entropy method

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Frontiers of Earth Science 2015年第4期9卷 722-731页

作者： Shaolei TANG Xiaofeng YANG di dong Ziwei LI State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

Sea surface temperature （SST） is an important variable for understanding interactions between the ocean and the atmosphere. SST fusion is crucial for acquiring SST products of high spatial resolution and coverage. This study introduces a Bayesian maximum entropy （BME） method for blending daily SSTs from multiple satellite sensors. A new spatiotemporal covariance model of an SST field is built to integrate not only single-day SSTs but also time-adjacent SSTs. In addition, AVHRR 30-year SST climatology data are introduced as soft data at the estimation points to improve the accuracy of blended results within the BME framework. The merged SSTs, with a spatial resolution of 4 km and a temporal resolution of 24 hours, are produced in the Western Pacific Ocean region to demonstrate and evaluate the proposed metho- dology. Comparisons with in situ drifting buoy observations show that the merged SSTs are accurate and the bias and root-mean-square errors for the comparison are 0.15℃ and 0.72℃, respectively.

关键词： sea surface temperature (SST) Bayesian maximum entropy (BME) remote sensing data fusion

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Synthesis and Crystal Structure of 4-[(1E)-(4-Hydroxy-3,5-dimethoxybenzylidene)-amino]-1,5-dimethyl-2-phenyl-2,3-dihydro-1H-pyrazol-3-one

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Chinese Journal of Structural Chemistry 2007年第5期26卷 511-514页

作者： SUN Yi-Feng ZHANG dong-di SONG Hua-Can Department of Chemistry Taishan University Shandong 271021 China College of Pharmacy Henan University Kaifeng Henan 475002 China School of Chemistry and Chemical Engineering Zhongshan University Guangzhou Guangdong 510275 China

The title compound （C20H21N3O4, Mr = 367.40） has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction. The crystal is of orthorhombic, space group P212121 with a = 7.5143（15）, b = 13.901（3）, c = 18.545（4）A , V = 1937.1（7） A^3, Z = 4, Dc = 1.260 g/cm^3, μ = 0.089 mm^-1, F（000） = 776, the final R = 0.0616 and wR = 0.0912. X-ray diffraction reveals that the molecule adopts an E configuration about the central C=N double bond. The intermolecular O-H…O hydrogen bond stabilizes the crystal structure by causing the formation of a supramolecular architecture.

关键词： antipyrine derivative Schiff bases synthesis crystal structure

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Space Efficient Quantization for Deep Convolutional Neural Networks

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Journal of Computer Science & Technology 2019年第2期34卷 305-317页

作者： dong-di Zhao Fan Li Kashif Sharif Guang-Min Xia Yu Wang School of Computer Science Beijing Institute of Technology Beijing 100081 China Wireless Networking and Sensing Laboratory Department of Computer Science University of North Carolina at Charlotte Charlotte NC 28223 U.S.A.

Deep convolutional neural networks(DCNNs)have shown outstanding performance in the fields of computer vision,natural language processing,and complex system *** the improvement of performance with deeper layers,DCNNs incur higher computational complexity and larger storage requirement,making it extremely difficult to deploy DCNNs on resource-limited embedded systems(such as mobile devices or Internet of Things devices).Network quantization efficiently reduces storage space required by ***,the performance of DCNNs often drops rapidly as the quantization bit *** this article,we propose a space efficient quantization scheme which uses eight or less bits to represent the original 32-bit *** adopt singular value decomposition(SVD)method to decrease the parameter size of fully-connected layers for further ***,we propose a weight clipping method based on dynamic boundary to improve the performance when using lower *** results demonstrate that our approach can achieve up to approximately 14x compression while preserving almost the same accuracy compared with the full-precision *** proposed weight clipping method can also significantly improve the performance of DCNNs when lower precision is required.

关键词： convolutional neural network memory compression network quantization

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Artificial Neural Network Modeling of Microstructure During C-Mn and HSLA Plate Rolling

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Journal of Iron and Steel Research International 2009年第2期16卷 80-83页

作者： TAN Wen LIU Zhen-yu WU di WANG Guo-dong The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

An artificial neural network （ANN） model for predicting transformed mierostrueture in conventional rolling process and therrnomechanical controlled process （TMCP） is proposed. The model uses austenite grain size and retained strain, which can be calculated by using microstructure evolution models, together with a measured cooling rate and chemical compositions as inputs and the ferrite grain size and ferrite fraction as outputs. The predicted re- suits show that the model can predict the transformed microstructure which is in good agreement with the measured one, and it is better than the empirical equations. Also, the effect of the alloying elements on transformed products has been analyzed by using the model. The tendency is the same as that in the reported articles. The model can be used further for the optimization of processing parameters, mierostructure and properties in TMCP.

关键词： artificial neural network TMCP microstructure ferrite grain size

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Retrieval of sea surface winds under hurricane conditions from GNSS-R observations

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Acta Oceanologica Sinica 2016年第9期35卷 91-97页

作者： JING Cheng YANG Xiaofeng MA Wentao YU Yang dong di LI Ziwei XU Cong State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of Sciences National Engineering Center for Geoinformatics Institute of Remote Sensing and Digital EarthChinese Academy of Sciences

Reflected signals from global navigation satellite systems（GNSSs） have been widely acknowledged as an important remote sensing tool for retrieving sea surface wind *** power of GNSS reflectometry（GNSS-R）signals can be mapped in delay chips and Doppler frequency space to generate delay Doppler power maps（DDMs）,whose characteristics are related to sea surface roughness and can be used to retrieve wind ***,the bistatic radar cross section（BRCS）,which is strongly related to the sea surface roughness,is extensively used in ***,a bistatic radar cross section（BRCS） map with a modified BRCS equation in a GNSS-R application is *** the BRCS map,three observables are proposed to represent the sea surface roughness to establish a relationship with the sea surface wind *** Hurricane Dennis（2005） GNSS-R data are then *** than 16 000 BRCS maps are generated to establish GMFs of the three ***,the proposed model and classic one-dimensional delay waveform（DW） matching methods are compared,and the proposed model demonstrates a better performance for the high wind speed retrievals.

关键词： global navigation satellite system-reflectometry Hurricane Dennis delay doppler maps bistatic radar cross section map sea surface wind speed

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Assembly of selenoniobate-vanadoniobate double-anion heteropolyoxoniobate:synthesis,structure,and magnetic property

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Tungsten 2023年第1期5卷 75-80页

作者： Zhi-Jie Liang Nan Li Hai-Bing Cheng Wei-Xin Du Guan Wang dong-di Zhang School of Textiles and Clothing Nantong UniversityNantong 226019China Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China

Recently,continuous interests and persisting efforts on heteropolyniobate have been dedicated to its preparation and *** this work,a novel Se-centred heteropolyniobate,[H2SeNb12(VO)4O40][Cu(en)2]2{[VNb12(VO)4O40][Cu(en)2]4}0.5·39H2O(en=ethanediamine),was *** compound was synthesized in aqueous solution by reacting the K7HNb6O19·13H2O with a mixture of vanadate(Ⅴ) and selenite(Ⅳ) source,which consists of two polyanions,i.e.,V-centred one and Se-centred *** architecture was characterized by infrared spectra,thermogravimetric analysis,X-ray powder diffraction spectroscopy,ultraviolet-visible and X-ray photoelectron ***,the magnetic property shows the antiferromagnetic interaction of the compound.

关键词： Heteropolyniobate Crystal structure Double-anion Self-assembly Magnetic property

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CT radiomics can help screen the coronavirus disease2019(COVID-19): a preliminary study

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Science China(Information Sciences) 2020年第7期63卷 222-229页

作者： Mengjie FANG Bingxi HE Li LI di dong Xin YANG Cong LI Lingwei MENG Lianzhen ZHONG Hailin LI Hongjun LI Jie TIAN School of Artificial Intelligence University of Chinese Academy of Sciences CAS Key Laboratory of Molecular Imaging Institute of Automation Chinese Academy of Sciences School of Electronic Electrical and Communication Engineering University of Chinese Academy of Sciences Department of Radiology Beijing Youan Hospital Capital Medical University Beijing Advanced Innovation Center for Big Data-Based Precision Medicine School of MedicineBeihang University

The coronavirus disease 2019(COVID-19) is raging across the world. The radiomics, which explores huge amounts of features from medical image for disease diagnosis, may help the screen of the COVID-19. In this study, we aim to develop a radiomic signature to screen COVID-19 from CT *** retrospectively collect 75 pneumonia patients from Beijing Youan Hospital, including 46 patients with COVID-19 and 29 other types of pneumonias. These patients are divided into training set(n = 50) and test set(n = 25) at random. We segment the lung lesions from the CT images, and extract 77 radiomic features from the lesions. Then unsupervised consensus clustering and multiple cross-validation are utilized to select the key features that are associated with the COVID-19. In the experiments, while twenty-three radiomic features are found to be highly associated with COVID-19, four key features are screened and used as the inputs of support vector machine to build the radiomic signature. We use area under the receiver operating characteristic curve(AUC) and calibration curve to assess the performance of our model. It yields AUCs of 0.862 and 0.826 in the training set and the test set respectively. We also perform the stratified analysis and find that its predictive ability is not affected by gender, age, chronic disease and degree of *** conclusion, we investigate the value of radiomics in screening COVID-19, and the experimental results suggest the radiomic signature could be a potential tool for diagnosis of COVID-19.

关键词： coronavirus disease 2019 radiomics pneumonia diagnosis

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Modeling of Strain-Induced Precipitation Kinetics and Evolution of Austenite Grains in Nb Microalloyed Steels

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Journal of Iron and Steel Research International 2008年第3期15卷 65-69页

作者： ZHOU Xiao-guang LIU Zhen-yu YUAN Xiang-qian WU di WANG Guo-dong LIU Xiang-hua State Key Laboratory of Rolling Technology and Automation Northeastern University Shenyang 110004 Liaoning China

Considering the effect of strain and chemical composition onprecipitation behavior, new models for the start and end time of Nb（C,N） precipitation in austenite under the conditions of different temperatures and strains have been investigated for Nb microalloyed steel. The value of n in the precipitation kinetic equation has been determined by using the available experimental data in literature, which indicated that n is a constant and independent of temperature. The values of the start and end time of the predicted precipitation are compared with the experimental values. Calculated results are in good agreement with the experimental results. Also, the evolution of austenite grains before ferrite transformation is simulated by taking the effect of precipitation into consideration. The measured austenite grain size is in good agreement with predicted one prior to ferrite transformation.

关键词： strain-induced precipitation start time precipitation static recrystallization grain size

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Insight into hexanuclear peroxotantalum complexes:synthesis,characterization,and efficient catalyst for amidation reaction

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Tungsten 2022年第2期4卷 158-167页

作者： Wei-Xin Du Meng-Yuan Cheng Ke Li Ya-Chun Ma Jing-Wen Shi dong-di Zhang Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Chemical EngineeringHenan UniversityKaifeng475004China Jiangxi Province Key Laboratory of Synthetic Chemistry Jiangxi Key Laboratory for Mass Spectrometry and InstrumentationEast China University of TechnologyNanchang330013China

Polyoxometalates(POMs),large oxoanions of the group 5 and 6 elements,attract attention due to their use as oxidation-stable catalysts and *** from the well-known V,Mo,and W POMs,the group V POMs of Ta assemble and are stable only in highly alkaline solution rather than acidic *** this paper,we successfully synthesized and structurally characterized two unprecedented peroxotantalum-containing clusters,KNa_(2)[HSe_(2)(TaO_(2))_(6)(OH)_(4)(H_(2)O)_(2)O_(13)]·15H_(2)O(1)and Cs_(2)K_(1.5)Na_(1.5)[Se_(4)(TaO_(2))_(6)(OH)_(3)O_(18)]·17H_(2)O(2),which comprises a 6-peroxo-6-tantalum core stabilized by two and four selenite centers,*** simple,one-pot synthesis of 1 and 2 involving addition of sodium selenite into the acidified hexatantalate aqueous solution in the presence of hydrogen peroxide could represent a general procedure for incorporating heteroatoms into peroxo-polyoxotantalate species,thus opening new possibilities for this emergent branch of polyoxotantalate ***,the catalytic properties of these two compounds were investigated using succinic anhydride and phenylamine as the model substrate,and compound 2 presents excellent catalytic activity in the amidation reactions of anhydrides and amines.

关键词： Polyoxotantalate Selenium Peroxo Amidation reaction Amides

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