检索结果-南通市图书馆

Journal of Integrative Plant Biology 2009年第10期51卷 942-950页

作者： feng-yun zhao Wen Liu Shi-Yong Zhang College of Life Sciences Shandong University of Technology Zibo 255049 China Institute of Rice Jining 272077 China

A comparative study of just cadmium （Cd） or heat and their combination treatments on some physiological parameters and the antioxidant systems in transgenic rice （Oryza sativa L. cv. Zhonghua No.11） carrying glutathione-S-transferase （GST, EC. 2.***.1.18） and catalasel （CAT1, EC. 1.***.1.6） and non-transgenics was conducted. The results revealed improved resistance in the transgenics to Cd and the combined Cd and heat stress than non-transgenics. Data showed that the activities of CAT, GST, superoxide dismutase （EC.1.***.1.1） and all components of the ascorbate-glutatbione cycle measured in the stressed transgenics shoots are significantly different from those of non-transgenics. Results indicated that co-expression of GST and CAT1 had an important effect on the antioxidant system, in particular, the whole ascorbate-glutathione cycle. The less oxidative damage induced by Cd and the stress combination in the transgenics resulted not only from the GST and CAT1 transgene but also from the coordination of the whole ascorbate-glutathione cycle.

关键词： ascorbate-glutathione cycle catalase combined cadmium and heat stress glutathione-S-transferase transgenic rice

Density and surface tension of binary mixtures of 1-ethyl-3-methylimdazolium nitrate with alcohols

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2012年第11期23卷 1295-1298页

作者： feng yun zhao Li Ya Liang Jian Ying Wang Yong Qi Hu College of Chemical and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018China

New experimental data of densities and surface tensions are presented for the binary mixtures of the ionic liquid 1-ethyl-3- methyl imidazolium nitrate （[EMIM]NO3） with methanol and ethanol. Measurements were performed at 298.15 K and atmospheric pressure, covering the whole composition range. Excess molar volumes VE and the surface tension deviations 8y have been determined. For the excess molar volumes of binary mixture, there is a region of negative VE at low IL mole fraction, passing through a minimum and then VE increases and becomes positive, showing maximum at higher IL mole fraction. It is shown that the surface tension deviations ~y of [EMIM]NO3 ＋ methanol system are positive but those of [EMIM]NO3 ＋ ethanol system are negative over the entire mole fraction range.

关键词： Ionic liquid Density Surface tension Excess molar volume

Gravity observations along the eastern margin of the Tibetan Plateau and an application to the Lushan MS 7.0 earthquake

在线全文

学校读者我要写书评

暂无评论

Earthquake Science 2013年第3期26卷 251-257页

作者： Wei-feng Liang yun-feng zhao yun-ma Xu Yi-qing Zhu Shu-song Guo Fang Liu Lian Liu Second Monitoring Center China Earthquake Administration

This paper introduces relative and absolute gravity change observations in the eastern portion of the Tibetan Plateau. We analyze and discuss a change that occurred in 2010 in the gravity along the eastern margin of the plateau and the relationship between this change and the 2013 Lushan Ms7.0 earthquake. Our results show that：（1） before the Lushan MsT.0 earthquake, gravity anomalies along the eastern margin of the Tibetan Plateau changed drastically. The Lushan earthquake occurred at the bend of the high gradient zone of gravity var- iation along the southern edge of the Longmenshan fault zone. （2） The 2013 Lushan earthquake occurred less than 100 km away from the epicenter of the 2008 Wenchuan earthquake. Lushan and Wenchuan are located at the center of a four- quadrant section with different gravity anomalies, which may suggest that restoration after the Wenchuan earthquake may have played a role in causing the Lushan earthquake. （3） A medium-term prediction based on changes in gravity anoma- lies was made before the Lushan Ms7.0 earthquake, in par- ticular, a prediction of epicenter location.

关键词： The eastern margin of the TibetanPlateau Gravity observation Gravity changeLushan earthquake Medium-term prediction

Hydrogen Peroxide-Mediated Growth of the Root System Occurs via Auxin Signaling Modification and Variations in the Expression of Cell-Cycle Genes in Rice Seedlings Exposed to Cadmium Stress

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2012年第12期54卷 991-1006页

作者： feng-yun zhao Ming-Ming Han Shi-Yong Zhang Kai Wang Cheng-Ren Zhang Tao Liu Wen Liu College of Life Sciences Shandong University of Technology Shandong Rice Research Institute

The link between root growth, H2O2, auxin signaling, and the ceil cycle in cadmium （Cd）-stressed rice （Oryza sativa L. cv. Zhonghua No. 11） was analyzed in this study. Exposure to Cd induced a significant accumulation of Cd, but caused a decrease in zinc （Zn） content which resulted from the decreased expression of OsHMA9 and OsZIP. Analysis using a Cd-specific probe showed that Cd was mainly localized in the meristematic zone and vascular tissues. Formation and elongation of the root system were significantly promoted by 3-amino-l,2,4-triazole （AT）, but were markedly inhibited by N,N＇. dimethylthiourea （DMTU） under Cd stress. The effect of H2O2 on Cd-stressed root growth was further confirmed by examining a gain-of-function rice mutant （carrying catalasel and glutathione-S-transferase） in the presence or absence of diphenylene iodonium. DR5-GUS staining revealed close associations between H2O2 and the concentration and distribution of auxin. H2O2 affected the expression of key genes, including OsYUCCA, OsPIN, OsARF, and OslAA, in the auxin signaling pathway in Cd-treated plants. These results suggest that H2O2 functions upstream of the auxin signaling pathway. Furthermore, H2O2 modified the expression of cell-cycle genes in Cd-treated roots. The effects of H2O2 on root system growth are therefore linked to auxin signal modification and to variations in the expression of cell-cycle genes in Cd-stressed rice. A working model for the effects of H2O2 on Cd-stressed root system growth is thus proposed and discussed in this paper.

关键词： Auxin signaling cadmium stress cell cycle hydrogen peroxide rice root system.

A Model of Competition with Environmental Taxes and Regulation Under Conditions of Oligopoly

在线全文

学校读者我要写书评

暂无评论

Systems Science and Systems Engineering 2002年第3期11卷 275-279页

作者： XIAO Jiang-wen, LUO yun-feng, zhao Yong, YUE Chao-yuanInstitute of Systems Engineering, Huazhong University of Science and Technology, Wuhan 430074, China Institute of Systems Engineering Huazhong University of Science and Technology Wuhan 430074 China

The Cournot static game with complete information is reviewed. A model of competition with environmental taxes under conditions of oligopoly is built based on the Cournot game, and some helpful conclusions are drawn from the model. A game model with regulation of government is also established. Finally the optimization problem of market structure is discussed.

关键词： game theory Cournot model oligopoly tax regulation

Assessment on Dietary Melamine Exposure from Tainted Infant Formula

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2009年第2期22卷 100-103页

作者： XU-DONG JIA NING LI ZHU-TIAN WANG yun-feng zhao YONG-NING WU AND WEI-XING YAN Institute of Nutrition and Food Safety Chinese Center for Disease Control and Prevention Beijing 100050 China

Objective To estimate the dietary melamine exposure in Chinese infants and young children from the consumption of melamine adulterated Sanlu infant formula. Methods Four age groups of infants and young children （3, 6, 12, and 24 months） were chosen as the assessed subjects and the maximum amount of infant formula consumption was estimated based on the recommended usage level in the package insert of Sanlu infant formula and other brands. Melamine was analyzed in 111 Sanlu infant fbrmula samples collected from the markets in Beijing and Gansu province using the LC-MS-MS with a limit of quantification of 0.05 mg/kg. Four levels of melamine concentration were chosen to estimate the dietary intakes, including the mean, median, 90th percentile, and maximum. Results The infants of 3 months had the highest intake of melamine, and with the increase of the age （inonth）, the intake decreased. Based on the median melamine concentration （1 000 mg/kg） as an example, the melamine intakes fur the infants of 3, 6, 12, and 24 months were 23.4, 21.4, 15.0, and 8.6 mg/kg bw/d, respectively. Conclusion Dietary melamine intakes from tainted Sanln infant formula significantly exceeded the TDI level （0.2 mg/kg bw/d） recommended by the WHO Expert Meeting in 2008. However, the present assessment has some limitations including the poor representative samples, the varied melamine concentrations in the adulterated Sanlu infant formula, and other brand infant formula possibly consumed by these infants.

关键词： Dietary exposure assessment Melamine Infant formula

Simultaneous Determination of Melamine, Ammelide, Ammeline, and Cyanuric Acid in Milk and Milk Products by Gas Chromatography-tandem Mass Spectrometry

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2009年第2期22卷 87-94页

作者： HONG MIAO SAI FAN YONG-NING WU LEI ZHANG PING-PING ZHOU JING-GUANG LI HUI-JING CHEN AND yun-feng zhao Institute of Nutrition and Food Safety Chinese Centre for Disease Control and Prevention Beijing 100050 China College of Veterinary Medicine China Agricultural University Beijing 100094 China

Objective To develop an analytical method for simultaneously qualitative and quantitative determination of melamine and triazine-related by-products including ammelide, ammeline, and cyanuric acid in milk and milk products by gas chromatography- tandem mass spectrometry （GC-MS/MS）. Methods Melamine and triazine-related by-products namely ammelide, ammeline and cyanuric acid in the samples were extracted in a solvent mixture of diethylamine, water, and acetonitrile （10：40：50, V/V/V）. After centrifugation, an aliquot of the supernatant was evaporated to dryness under a gentle stream of nitrogen gas, and then melamine and triazine-related by-products were derivatized using BSTFA with 1% TMCS. The derivatives of melamine and its analogues were determined by gas chromatography/tandem mass spectrometry using multiple reactional monitoring （MRM） with 2, 6-Diamino-4-chloropyrimidine （DACP） being used as an internal standard. Results The linear detectable ranges were from 0.004 mg/kg to 1.6 mg/kg for melamine, ammelide, ammeline, and cyanuric acid with a correlation coefficient no less than 0.999. The recovery rates of the tour compounds in spiked blank milk powder at concentrations 0.5, 1, 2 mg/kg were between 61.4%-117.2%, and the relative standard deviation was no more than 11.5% （n=6）. The detection limits of melamine, ammelide, ammeline and cyanuric acid in milk powder were 0.002 mg/kg with a ratio of signal to noise of 3. Conclusion This GC-MS/MS method for simultaneous determination of melamine, ammelide, ammeline, and cyanuric acid in milk and milk products is sensitive and specific.

关键词： Melamine Ammelide Ammeline Cyanuric acid GC-MS/MS Milk products

Understanding the local structure and thermophysical behavior of Mg-La liquid alloys via machine learning potential

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 439-449页

作者： Jia zhao Taixi feng Guimin Lu National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China Joint International Laboratory for Potassium and Lithium Strategic Resources East China University of Science and TechnologyShanghai 200237China

The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(DPMD) simulation driven via machine learning to promote the development of Mg-La alloys. The robustness of the trained deep potential(DP) model was thoroughly evaluated through several aspects, including root-mean-square errors(RMSEs), energy and force data, and structural information comparison results;the results indicate the carefully trained DP model is reliable. The component and temperature dependence of the local structure in the Mg-La liquid alloy was analyzed. The effect of Mg content in the system on the first coordination shell of the atomic pairs is the same as that of temperature. The pre-peak demonstrated in the structure factor indicates the presence of a medium-range ordered structure in the Mg-La liquid alloy, which is particularly pronounced in the 80at% Mg system and disappears at elevated temperatures. The density, self-diffusion coefficient, and shear viscosity for the Mg-La liquid alloy were predicted via DPMD simulation, the evolution patterns with Mg content and temperature were subsequently discussed, and a database was established accordingly. Finally, the mixing enthalpy and elemental activity of the Mg-La liquid alloy at 1200 K were reliably evaluated,which provides new guidance for related studies.

关键词： magnesium-lanthanum liquid alloys local structure macroscopic properties thermodynamic behavior deep potential mo-lecular dynamic simulation

A Cross Attention Transformer-Mixed Feedback Video Recommendation Algorithm Based on DIEN

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2025年第1期82卷 977-996页

作者： Jianwei Zhang Zhishang zhao Zengyu Cai Yuan feng Liang Zhu Yahui Sun College of Software Engineering Zhengzhou University of Light IndustryZhengzhou450000China Faculty of Information Engineering Xuchang Vocational Technical CollegeXuchang461000China College of Computer Science and Technology Zhengzhou University of Light IndustryZhengzhou450000China College of Electronics and Information Zhengzhou University of Light IndustryZhengzhou450000China

The rapid development of short video platforms poses new challenges for traditional recommendation *** systems typically depend on two types of user behavior feedback to construct user interest profiles:explicit feedback(interactive behavior),which significantly influences users’short-term interests,and implicit feedback(viewing time),which substantially affects their long-term ***,the previous model fails to distinguish between these two feedback methods,leading it to predict only the overall preferences of users based on extensive historical behavior ***,it cannot differentiate between users’long-term and shortterm interests,resulting in low accuracy in describing users’interest states and predicting the evolution of their *** paper introduces a video recommendationmodel calledCAT-MFRec(CrossAttention Transformer-Mixed Feedback Recommendation)designed to differentiate between explicit and implicit user feedback within the DIEN(Deep Interest Evolution Network)*** study emphasizes the separate learning of the two types of behavioral feedback,effectively integrating them through the cross-attention ***,it leverages the long sequence dependence capabilities of Transformer technology to accurately construct user interest profiles and predict the evolution of user *** results indicate that CAT-MF Rec significantly outperforms existing recommendation methods across various performance *** advancement offers new theoretical and practical insights for the development of video recommendations,particularly in addressing complex and dynamic user behavior patterns.

关键词： Video recommendation user interest cross-attention transformer

A versatile synthetic strategy towards rare earth based metal-organic frameworks

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2025年

作者： Quan Shi yun-Hao Xu Ming-Hui Chen Peng zhao Wen-Bo Deng Ji Xiong Kai Guo Ya-Qing feng Bao Zhang School of Chemical Engineering and Technology Tianjin University Tianjin Collaborative Innovation Center of Chemical Science and Engineering Guangdong Laboratory Chemistry & Fine Chemical Industry Jieyang Center

Rare earth metal-organic frameworks (RE-MOFs) have drawn wide attention owing to diverse network structures and various application ***,due to the unpredictable formation of the nodes,it is still challenging to design novel RE-MOFs.A novel versatile strategy was developed employing a RE-acetate complex (RE2(CH3COO)6·4H2O) as a precursor to construct RE-MOFs.2D RE-MOFs (RE-DBP) and 3D RE-MOFs (RE-TCPP) could be obtained by using dicarboxylic porphyrin ligands H2DBP and tetracarboxylic porphyrin ligands H2TCPP,*** RE-MOFs were further synthesized to verify the universality of the *** crystalline RE-MOFs could also be prepared at room temperature via the developed strategy,which could significantly promote large-scale preparation and practical application of *** proof of the concept,the performance of porphyrin-based RE-MOFs was investigated in the photocatalytic cycloaddition of CO2with *** the RE-DBP(Co) MOFs,Tb-DBP(Co) exhibited the best photocatalytic performance,which was also greater than that of the corresponding 3D MOF Tb-TCPP(Co) due to the optimal 2D structure and thus the accelerated photogenerated charge separation and transfer *** work not only provides a novel versatile strategy to design and develop RE-MOFs,but also proposes a promising approach for the potential bulk production of RE-MOFs at room temperature.

关键词：