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Pedosphere 2009年第2期19卷 176-188页

作者： YANG Xiao-Hua WANG fu-Min HUANG Jing-Feng WANG Jian-wen WANG Ren-Chao shen Zhang-Quan WANG Xiu-Zhen Institute of Agricultural Remote Sensing ＆ Information Application Zhejiang University Hangzhou 310029 China Meteorological and Hydrographic Department of General Staff Headquarters Beijing 100081 China Zhejiang Meteorological Institute Hangzhou 310004 China

The radial basis function （RBF） emerged as a variant of artificial neural network. Generalized regression neural network （GRNN） is one type of RBF, and its principal advantages are that it can quickly learn and rapidly converge to the optimal regression surface with large number of data sets. Hyperspectral reflectance （350 to 2500 nm） data were recorded at two different rice sites in two experiment fields with two cultivars, three nitrogen treatments and one plant density （45 plants m^-2）. Stepwise multivariable regression model （SMR） and RBF were used to compare their predictability for the leaf area index （LAI） and green leaf chlorophyll density （GLCD） of rice based on reflectance （R） and its three different transformations, the first derivative reflectance （D1）, the second derivative reflectance （D2） and the log-transformed reflectance （LOG）. GRNN based on D1 was the best model for the prediction of rice LAI and CLCD. The relationships between different transformations of reflectance and rice parameters could be further improved when RBF was employed. Owing to its strong capacity for nonlinear mapping and good robustness, GRNN could maximize the sensitivity to chlorophyll content using D1. It is concluded that RBF may provide a useful exploratory and predictive tool for the estimation of rice biophysical parameters.

关键词： biophysical parameters radial basis function regression model remote sensing rice

Influence of specific speed on hydraulic performances and pressure fluctuations in mixed-flow pumps

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排灌机械工程学报 2023年第10期41卷 981-987页

作者： fu Yanxia JIA Qi shen Yang PACE Giovanni School of Energy and Power Engineering Jiangsu UniversityZhenjiangJiangsu 212013China Zhenjiang Fire and Rescue Division ZhenjiangJiangsu 212000China Sitael S.P.A. Pisa 56121Italy

A series of steady and unsteady numerical calculations of the internal flow in mixed-flow pumps with three different specific speeds were carried out based on the N-S equation coupled with the standard k-εturbulence model under different operating conditions to investigate the relationship between the impeller specific speed and the pump performance as well as pressure ***,the pump performance and pressure pulsations inside the mixed-flow pump with three different specific speeds were also analyzed and compared with the corresponding test *** the results,the averaged deviations between the predicted and tested head among different impellers are below 5%,and with respect to the equivalent impeller specific speeds of 280 and 260,the values are 4.30%and 3.69%,*** all the impeller schemes,the best efficiency point of the mixed-flow pump is found at the flow rate of 1.2 Q_(d) and the higher head deviation occurs at lower flow ***,it can be found that the specific speed has a slight effect on the pressure fluctuation in the ***,it is determined that the pump performance curves calculated by numerical simu-lations have good agreement with the relevant experimental results,which verifies that the numerical methods used in the present study are accurate to a certain ***,the results also provide some references to the pressure pulsation analysis and the performance improvement of the mixed-flow pump design.

关键词： mixed-flow pumps impeller specific speed hydraulic performance pressure pulsation numerical simulation experiment

Advances and Developing Tendency of Water Use Efficiency in Plant Biology

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Agricultural Sciences in China 2009年第7期8卷 855-863页

作者： CHEN Zhao-bo TANG Jiao-wen ZHANG fu Graduate School Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China China Rural Technology Development Center Beijing 100045 P.R.China

Biological water saving is one of the major fields of water saving agriculture in the future and has an enormous potential in agricultural production. In this paper, the necessity and urgency of developing high water use efficiency in plant biology were dissertated firstly, and the research progresses at home and abroad were reviewed as following aspects： mechanisms of drought resistance and high water use efficiency, criterions for identifying and evaluating drought resistance and water use efficiency, genetic improvement for drought resistance and water use efficiency, water saving irrigation technology based on the physiological regulation and control in crop plants. Major problems in the research field at present were put forward, and development tendency of water use efficiency in plant biology in the future were also discussed.

关键词： plant drought resistance water use efficiency identification evaluation genetic improvement

Mechanism of chain propagation for the synthesis of polyoxymethylene dimethyl ethers

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Journal of Energy Chemistry 2013年第6期22卷 833-836页

作者： Yupei Zhao Zheng Xu Hui Chen Yuchuan fu Jianyi shen Laboratory of Mesoscopic Chemistry School of Chemistry and Chemical Engineering Nanjing University

Polyoxymethylene dimethyl ethers(PODE)were synthesized from the reaction of paraformaldehyde with dimethoxymethane(DMM)over different acid catalysts at different *** were found to follow the Schulz-Flory distribution *** chain propagation proceeds through the insertion of an individual segment of CH2O one by one,while the simultaneous insertion of a few CH2O segments or their assembly is *** to the restriction of this law,it is difficult to increase the selectivity to the desired products(e.g.,PODE3 4).

关键词： polyoxymethylene dimethyl ethers (PODE) diesel additive chain propagation product distribution Schulz-Flory law

Synthesis of a new 2,2':6',2''-terpyridine derivative and its coordination property

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Chinese Chemical Letters 2007年第5期18卷 530-532页

作者： Yong Chen Xi Juan Zhao Jun Feng Zhang wen fu fu Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate University of Chinese Academy of Sciences Beijing 100039 China College of Chemistry and Chemical Engineering Yunnan Normal University Kunming 650092 China

A novel compound, （E）-4′-（4-（but-1-en-3-ynyl）phenyl）-2,2′：6′,2″-terpyridine 1 was synthesized from 4′-（4-bromomethylphenyl）-2,2P：6P,2PP-terpyridine phosphonium salt 2 and propargylaldehyde via Wittig reaction, and characterized by EI-MS and ^1H NMR as well as elemental analysis. The spectral changes of the compound in the presence of transition metal ions, such as Cu（I） or Zn（ID, are investigated.

关键词： Polypyridine ligands Synthesis Coordination

Comparative study of the cytotoxicity of the nanosized and microsized tellurium powders on HeLa cells

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Frontiers in Biology 2013年第4期8卷 444-450页

作者： Huanan wen Jiaxin ZHONG Bei shen Tao GAN Chao fu Zhihong ZHU Rui LI Xu YANG Hubei Key Laboratory of Genetic Regulation and Integrative Biology College of Life Science Central China Normal University Wuhan 430079 China Institute of Nanotechnology College of Physical Science and Technology Central China Normal University Wuhan 430079 China

To compare the cytotoxicity on HeLa cells induced by nanosized and microsized tellurium powders, HeLa cells were exposed to different concentrations of tellurium powders （0, 50, 100, 150 and 200 μg/mL） for 12 h. In this study, detection of a series of biomarkers, including reactive oxygen species （ROS）, glutathione （GSH）, 8-hydroxy-2＇- deoxyguanosine （8-OHdG）, in addition to DNA and protein crosslink （DPC） and MTT assay, were conducted to evaluate the cytotoxicity. It is indicated that compared with the control group, there was no significant difference in the induced cytotoxicity at concentrations lower than 50 μg/mL for both nanosized and microsized tellurium powders. While there appears a significant difference in the induced cytotoxicity for nanosized tellurium powders when the concentration is higher than 100 μg/mL as well as for microsized tellurium powders when the concentration is higher than 200 μg/mL. Moreover, it is found that the cytotoxicity induced on HeLa cells exhibits a certain dose-effect relationship with the concentration of tellurium powders. A conclusion has been reached that the toxicity on HeLa cells can be induced by both nanosized and microsized tellurium powders, and the toxicity of the nanosized tellurium powders is significantly greater than the microsized one.

关键词： nanosized and microsized tellurium powder HeLa cells oxidative damage reactive oxygen species (ROS),glutathione (GSH) DNA and protein crosslink (DPC) 8-hydroxy-2'-deoxyguanosine (8-OHdG)

Rapidly growing primordial black holes as seeds of the massive high-redshift JWST Galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 139-146页

作者： Guan-wen Yuan Lei Lei Yuan-Zhu Wang Bo Wang Yi-Ying Wang Chao Chen Zhao-Qiang shen Yi-fu Cai Yi-Zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Deep Space Exploration Laboratory/Department of Astronomy School of Physical SciencesUniversity of Science and Technology of ChinaHefei 230026China Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina

A group of massive galaxies at redshifts of z■7 have been recently detected by the James Webb Space Telescope(JWST),which were unexpected to form at such an early time within the standard Big Bang *** this work,we propose that this puzzle can be explained by the presence of some primordial black holes(PBHs)with a mass of~1000M_(⊙).These PBHs act as seeds for early galaxy formation with masses of~10^(8)-10^(10)M_(⊙)at high redshift,hence accounting for the JWST *** use a hierarchical Bayesian inference framework to constrain the PBH mass distribution models,and find that the Lognormal model with the M_(c)~750M_(⊙)is preferred over other *** rapidly growing BHs are expected to have strong radiation and may appear as high-redshift compact objects,similar to those recently discovered by *** we focused on PBHs in this work,the bound on the initial mass of the seed black holes remains robust even if they were formed through astrophysical channels.

关键词： primordial black hole dark matter halo black hole accretion primordial galaxies

Anti-synchronization in Different Hyperchaotic Systems

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Communications in Theoretical Physics 2008年第10期50卷 907-912页

作者： DOU fu-Quan SUN Jian-An DUAN wen-Shan College of Physics and Electronics Engineering Northwest Normal University Lanzhou 730070 China

Based on active control theory, anti-synchronization between two different hyperchaotic systems is investigated. The sufficient conditions for achieving anti-synchronization of two different hyperchaotic systems are derived. Moreover, numerical simulations are presented for hyperehaotic Lorenz-Chen system, hyperchaotic Lorenz-Lu system, and hyperchaotic Chen Lu system to verify the effectiveness and feasibility of the proposed anti-synchronization scheme.

关键词： anti-synchronization hyperchaotic system active control

Synthesis and Spectroscopic Properties of Cyclotriphosphazenes Containing 6-(4-Hydroxyphenyl)-2,2'-bipyridine Side Groups

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Chemical Research in Chinese Universities 2007年第6期23卷 679-682页

作者： ZHANG Jun-feng GAN Xin OU Xue-mei fu wen-fu College of Chemistry and Chemical Engineering Yunnan Normal University Kunming 650092 P. R. China Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 P. R. China

Two novel cyclotriphosphazene derivatives containing 6- （4-hydroxyphenyl）-2,2′-bipyridine （hopbp） side groups, N3 P3 （dobp） 2 （hopbp） 2 （ 1 ） and N3 P3 （dobp）（hopbp） 4 （2）（ dobp = 2,2′-dioxybiphenyl）, were synthesized and characterized. These compounds display strong fluorescent emission both in solution and in solid state. Their absorption and emission spectra are sensitive to proton： the addition of HBF4 to the methanol and dichloromethane solution（9： 1, volume ratio） of compound 1 led to a red-shift from 350 to 460 nm for the emission spectrum, and the process was also characterized by isosbestic points of absorption spectra at 267, 287 and 313 nm.

关键词： Cyelotriphosphazene Bipyridine Proton Spectra

Prognostic effect analysis of molecular subtype on young breast cancer patients

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Chinese Journal of Cancer Research 2015年第4期27卷 428-436页

作者： Hong-Liang Chen Ang Ding fu-wen Wang Department of Breast Surgery Obstetrics and Gynecology Hospital of Fudan University

Objective： To make a prognostic effect analysis of molecular subtype on young breast cancer ***： Totally 187 cases of young breast cancer patients less than 40 years old treated in Obstetrics and Gynecology Hospital of fudan University between June 2005 and June 2011 were included in our study. We described their clinical-pathological characteristics, disease-free survival（DFS） rate, and overall survival（OS） rate after a median follow-up period of 61 months. The factors associated with prognosis were also evaluated by univariate and multivariate ***： All patients were premenopausal, with an average age of 35.36±3.88 years old. The mean tumor size was 2.43±1.53 cm. Eighty-one cases had lymph node metastasis（43.3%）, 126 cases had lymphovascular invasion（67.4%）, and 125 cases had histological grade III（66.8%） disease. Twenty-seven cases（14.4%） were Luminal A subtype, 99 cases（52.9%） were Luminal B subtype, 29 cases（15.5%） were human epidermal growth factor receptor 2（HER-2） overexpression subtype, while 32 cases（17.1%） were triple negative breast cancer（TNBC） subtype according to 2013 St Gallen expert consensus. One hundred and thirty-five cases underwent mastectomy whereas 52 cases had breast-conserving surgery. One hundred and seventy-eight cases underwent adjuvant or neoadjuvant chemotherapy. Recurrence or metastasis occurred in 29 cases, 13 of which died. The 5-year DFS and OS rates were 84% and 92%. Multivariate analysis showed that nodal status（P=0.041） and molecular subtype（P=0.037） were both independent prognostic factors of DFS, while nodal status（P=0.037） and TNBC subtype（P=0.048） were both independent prognostic factors of OS. Conclusions： Molecular subtype is an independent prognostic factor of young breast cancer patients. TNBC has a high risk of relapse and death.

关键词： Molecular subtype young breast cancer prognosis