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Journal of Integrative Agriculture 2013年第10期12卷 1783-1790页

作者： DONG Yu-xiu WANG xiu-feng CUI xiu-min Key Laboratory of Crop Biology Shandong Agricultural University College of Resources and Environment Shandong Agricultural University

Nitric oxide（NO）,a bioactive signaling molecule,serves as an antioxidant and anti-stress agent under abiotic stress.A hydroponics experiment was conducted to investigate the effects of sodium nitroprusside（SNP）,a NO donor,on tomato seedlings exposed to 50 μmol L-1CuCl *** results show that copper is primarily stored in the soluble cell sap fraction in the roots,especially after treatment with Cu＋SNP treatment,which accounted for 66.2% of the total copper *** copper concentration gradually decreased from the roots to the *** the leaves,exogenous NO induces the storage of excess copper in the cell *** stress decreases the proportion of copper integrated with pectates and proteins,but exogenous NO remarkably reverses this *** alleviating effect of NO is blocked by ***,exogenous NO is likely involved in the regulation of the subcellular copper concentrations and its chemical forms under copper *** exogenous NO inhibited the absorption and transport of excess copper to some extent,the copper accumulation in tomato seedlings significantly increased under copper *** use of exogenous NO to enhance copper tolerance in some plants is a promising method for copper remediation.

关键词： tomato seedlings nitric oxide copper stress subcellular distribution chemical form

Weyl Spectrum of Upper Triangular Operator Matrices

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Acta Mathematica Sinica,English Series 2020年第7期36卷 783-796页

作者： xiu feng WU Jun Jie HUANG School of Mathematical Sciences Inner Mongolia Normal UniversityHohhot 010022P.R.China School of Mathematical Sciences Inner Mongolia UniversityHohhot 010021P.R.China

This paper is concerned with general n×n upper-triangular operator matrices with given diagonal *** characterizations of perturbations of their left(***)Weyl spectrum and Weyl spectrum are given,based on the space decomposition ***,some sufficient and necessary conditions are given under which the left(***)Weyl spectrum and the Weyl spectrum of such operator matrix,respectively,coincide with the union of the left(***)Weyl spectrum and the Weyl spectrum of its diagonal entries.

关键词： technique. diagonal spectrum

Purification and utilization of garlic processing wastewater in lotus pond wetlands

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Water Science and Engineering 2014年第4期7卷 395-402页

作者： Jun PANG Xue-ling feng xiu-feng WANG College of Arts Taishan University Linyi Research Institute of Environmental Protection College of Horticultural Science and Engineering Shandong Agricultural University

Based on the experiments of utilization of garlic processing wastewater in a lotus pond, this study demonstrates that lotus pond wetlands have a remarkable ability to remove organic pollutants and decrease chemical oxygen demand （CODCr）, biochemical oxygen demand （BOD5）, and suspended substances （SS） in garlic processing wastewater. Results also show evident effects of lotus roots on absorption of NH3-N. The pH value in a lotus pond with wastewater discharged was relatively stable. The water quality in the lotus pond reached the class Ⅱ emission standard, according to the Integrated Wastewater Discharge Standard （GB8978-1996）, seven days after pretreated garlic processing wastewater had been discharged into the lotus pond. Garlic processing wastewater irrigation does not produce pollution in the pond sediment and has no negative effect on the growth of lotus roots. Due to utilization of garlic processing wastewater, the output of lotus roots increased by 3.0% to 8.3%, and the quality of lotus roots was improved. Therefore, better purification and utilization results can be achieved.

关键词： lotus pond wetland garlic processing wastewater ecological treatment removalrate purification and utilization

Leakage Prediction Method for Contacting Mechanical Seals with Parallel Faces

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Chinese Journal of Mechanical Engineering 2010年第1期23卷 7-15页

作者： SUN Jianjun WEI Long feng xiu GU Boqin College of Mechanical and Electronic Engineering Nanjing Forestry UniversitY Nanjing 21003 7 China Department of Engineering Mechanics Southeast University Nanjing 210096 China Fluid Sealing Technique Development Center Nanjing College of Chemical Technology Nanjing 210048 China College of Mechanical and Power Engineering Nanjing University of Technology Nanjing 210009 China

Since the beginning of the 20th century, many researches on the sealing characteristic of mechanical seals were carried out broadly and in depth by various methods and some leakage models were built. But due to the lack of the way to characterize the main factors of influence on the leakage, most of the early researches were based on the assumptions that the seal faces topography and the frictional conditions were invariant. In the early built models, the effect of the surface topography change of the seal face on the leakage rate was neglected. Based on the fractal theory, the contact of end faces of the rotary and stationary rings was simplified to be the contact of a rough surface and an ideal rigid smooth surface, and the contact interface＇s cavity size-distribution function as well as the fractal characteristic of the cavity profile curve was discussed. By analyzing the influence of abrasion on the seal face topography and the leakage channel, the time-correlation leakage prediction model of mechanical seals based on the fractal theory was established and the method for predicting the leakage rate of mechanical seals with parallel plane was proposed. The values of the leakage rate predicted theoretically are similar to the measured values of the leakage rate in the model test and in situ test. The experimental results indicate that the leakage rate of mechanical seals is a transient value. The surface topography of the end faces of the seal tings and its change during the frictional wear of mechanical seals can be accurately characterized by the fractal parameters. Under the work conditions of changeless frictional mechanism, the fractal parameters measured or calculated based on the accelerated testing equation can be used to predict the leakage rate of mechanical seal in service. The proposed research provides the basis for determining the leakage state and predicting working life of mechanical seal.

关键词： mechanical seal leakage rate fractal theory frictional wear accelerated test model

Effects of Exogenous Silicon on Photosynthetic Capacity and Antioxidant Enzyme Activities in Chloroplast of Cucumber Seedlings Under Excess Manganese

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Agricultural Sciences in China 2009年第1期8卷 40-50页

作者： feng Jian-peng SHI Qing-hua WANG xiu-feng College of Horticultural Science and Engineering Shandong Agricultural University Tai＇an 271018 P.R.China State Key Laboratory of Crop Biology Tai＇an 271018 P.R.China

Effects of silicon on photosynthetic parameters and antioxidant enzymes of chloroplast in cucumber seedlings under excess Mn were studied. Compared with the control, excess Mn significantly inhibited net photosynthetic rate （Pn）, stomatal conductance, as well as the maximum yield of the photosystem II photochemical reactions （Fv/Fm） and the quantum yield of photosysytem II electron transport （Φ PSII）, application of Si reversed the negative effects of excess Mn. In the further investigation, it was obtained that application of Si significantly increased the activities of enzymes related with ascorbate-glutathione cycle including ascorbate peroxidase （APX）, dehydroascorbate reductase （DHAR） and glutathione reductase （GR） in cucumber chloroplast under excess Mn, this could be responsible for the lower accumulation of H2O2 and lower lipid peroxidation of chloroplast induced by Mn, and resulted in keeping higher photosynthesis.

关键词： cucumber excess manganese photosynthesis chlorophyll fluorescence chloroplast antioxidant enzymes

Effects of benthic algae on release of soluble reactive phosphorus from sediments: a radioisotope tracing study

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Water Science and Engineering 2015年第2期8卷 127-131页

作者： xiu-feng Zhang Xue-ying Mei Department of Ecology and Institute of Hydrobiology Jinan University College of Resources and Environment Anhui Agricultural University

To evaluate the effect of benthic algae on soluble reactive phosphorus（SRP） release from sediments in shallow lakes, experiments on SRP release with and without benthic algae in sediment cores and an experiment on SRP uptake by benthic algae were conducted using the radioisotope（32P） tracing method. The dissolved oxygen（DO） concentration in sediment cores was also investigated. The results show that benthic algae effectively reduce the release of SRP from sediments to overlying water. The uptake of SRP by benthic algae, which is the direct way in which benthic algae affect the SRP release from sediments, is low in filtered water and increases with the SRP concentration. However, in the experiment, the increased uptake rate lasted for a short time（in one hour）, and after that it returned to a low rate. Benthic algae make the DO concentration and the oxic layer thickness increased, which can indirectly reduce the SRP release from sediments. These findings indicate that benthic algae can reduce the SRP release from sediments in both direct and indirect ways. It seems that the indirect way also plays an important role in reducing the SRP release from sediments.

关键词： Sediment Benthic algae Soluble reactive phosphorus release Soluble reactive phosphorus uptake Shallow lake

Two new eudesmane sesquiterpenes from Lactuca sativa *** L

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Chinese Chemical Letters 2009年第10期20卷 1211-1214页

作者： Yi feng Han Gui xiu Cao Min Xia Departmem of Chemistry Zhejiang Sci-Tech University Hangzhou 310018 China

Two new eudesmane sesquiterpene lactones were isolated from the stalk of Lactuca sativa vat anagustata L and their structures were elucidated by means of spectroscopic methods, including 2D NMR （1H-1H COSY, HMBC and NOESY） as 1β-O-β-D- glucopyranosyl-4α-hydroxyl-5α, 6β, 11βH-eudesma-12, 6α-olide （1） and 1β-hydroxyl-15-O-（p-methoxyphenylacetyl）-5α, 6β, 11 βH-eudesma-3-en- 12, 6a-olide （2）.

关键词： Lactuca sativa var. anagustata L Compositae Eudesmane sesquiterpene

Liquid-phase epoxidation of styrene with O_2 over alkali metal salt impregnated CoAPO-5

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Chinese Chemical Letters 2012年第1期23卷 53-56页

作者： xiu feng Shi Bao Ping Shi Bin Bin Fan Rui feng Li Institute of Special Chemicals Taiyuan University of TechnologyTaiyuan 030024China College of Chemical and Biological Engineering Taiyuan University of Science and TechnologyTaiyuan 030021China

Liquid-phase epoxidation of styrene with atmospheric O_2 was conducted over CoAPO-5 molecular *** catalytic performance of CoAPO-5 can be significantly improved by alkali metal salt impregnated on it,and styrene conversion and selectivity to styrene oxide reached 85%and 69%respectively when CsCl was impregnated on *** catalyst was recyclable and exhibited similar catalytic activity and selectivity even after three catalytic reaction cycles.

关键词： CoAPO-5 Styrene epoxidation Oxygen Alkali metal salt

Changes of Nitrate Reductase Activity in Cucumber Seedlings in Response to Nitrate Stress

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Agricultural Sciences in China 2010年第2期9卷 216-222页

作者： YANG Xiao-yu WANG xiu-feng WEI Min YANG feng-juan SHI Qing-hua College of Horticulture Science and Engineering Shandong Agricultural University Tai＇an 271018 P.R.China State Key Laboratory of Crop Biology Shandong Agricultural University Tai＇an 271018 P.R.China

In China, nitrogen fertilizer application rates in intensive agricultural systems have increased dramatically in recent years, especially in protected vegetable production systems. This excessive use of nitrogen fertilizer has resulted in soil secondary salinization, which has become a significant environmental stress for crops such as cucumber, in the protected farmland of China. So it is necessary to illuminate how crops respond to nitrate stress. The objective of this work was to examine the effects of increased nitrate concentration [14 （CK） and 140 mmol L^-1 （T）] on NO3- concentration, and in vitro and in vivo nitrate reductase activities in the roots and leaves of cucumber （Cucumis sativus L. cv. Xintaimici） seedlings with hydroponic culture. The results showed that the NO3- concentration in the roots and leaves of T seedlings significantly increased over treatment course, and at 12 d increased by 1.08 and 1.72 times with respect to CK seedlings, respectively; in vitro nitrate reductase activity of T was increased dramatically to 1.74 times of CK in the roots at 2 d and 1.56 times of CK in the leaves at 6 d, and then decreased. At 12 d, in vitro activity was still 24.3% higher in the roots and only 9.9% lower in the leaves than CK. Compared with in vitro nitrate reductase activity, in vivo activity responded differently to the increase of treatment time. At the beginning, in vivo nitrate reductase activity in the roots and leaves of T had no significant difference from CK, whereas with the increase of treatment duration, the activity decreased. At 12 d, in vivo activity in the roots and leaves of T lowered by 20.1 and 52.8% with respect to CK, respectively. This evidence suggests that posttranslational activation of nitrate reductase in cucumber seedlings may be seriously inhibited by nitrate stress.

关键词： cucumber NO3- concentration nitrate reductase nitrate stress

Theoretical Study on the Reaction Mechanism between Dichlorocarbene and Armchair Single-walled Carbon Nanotubes

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Chinese Journal of Structural Chemistry 2006年第9期25卷 1120-1128页

作者： LI Rui-Fang SHANG Zhen-feng XU xiu-Fang WANG Gui-Chang Department of Chemistry Nankai University Tianjin 300071 China

The reaction mechanism between CC12 and armchair single-walled carbon nanotubes （ASWCNTs）（3,3） and （4,4） has been studied by semiempirical AM1 and ab initio methods. The activation barriers of CC12 adding to ASWCNT （3,3） and （4,4） are computed and compared. The lower barrier of CC12 forms cycloaddition isomer on （3,3） maybe because the strain energy of （3,3） is larger than that of （4,4）. Our theoretical results are consistent with the experimental results.

关键词： armchair single-walled carbon nanotubes dichlorocarbene reaction mechanism theoretical study