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Root Exudates, Rhizosphere Zn Fractions, and Zn Accumulation of Ryegrass at Different Soil Zn Levels

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Pedosphere 2007年第3期17卷 389-396页

作者： XU Wei-Hong LIU Huai MA Qi-Fu XIONG Zhi-Ting college of Resources and Environmental sciences Southwest University Chongqing 400716 （China） college of Plant Protection Southwest University Chongqing 400716 （China） Soil Science and Plant Nutrition University of Western Australia Crawley WA 600Y （ Australia） college of Resources and Environmental sciences Wuhan University Wuhan 430072 （China）

A glasshouse experiment was conducted using a root-bag technique to study the root exudates, rhizosphere Zn fractions, and Zn concentrations and accumulations of two ryegrass cultivars （Lolium perenne L. cvs. Airs and Tede） at different soil Zn levels （0, 2. 4, 8, and 16 mmol kg^-1 soil）. Results indicated that plant growth of the two cultivars was not advérsely affected at soil Zn level ≤ 8 mmol kg^-1. Plants accumulated more Zn as soil Zn levels increased, and Zn concentrations of shoots were about 540 μg g^-1 in Aris and 583.9 μg g^-1 in Tede in response to 16 mmol Zn kg^-1 soil. Zn ratios of shoots to roots across the soil Zn levels were higher in Tede than in Airs, corresponding with higher rhizosphere available Zn fractions （exchangeable, bound to manganese oxides, and bound to organic matter） in Airs than in Tede. Low-molecular-weight （LMW） organic acids （oxalic, tartaric, malic, and succinic acids） and amino acids （proline, threonine, glutamic acid, and aspartic acid, etc.） were detected in root exudates, and the concentrations of LMW organic acids and amino acids increased with addition of 4 mmol Zn kg^-1 soil compared with zero Zn addition. Higher rhizosphere concentrations of oxalic acid, glutamic acid, alanine, phenylalanine, leucine, and proline in Tede than in Airs likely resulted in increased Zn uptake from the soil by Tede than by Airs. The results suggested that genotypic differences in Zn accumulations were mainly because of different root exudates and rhizosphere Zn fractions.

关键词： plant Zn accumulation rhizosphere Zn fractions root exudates ryegrass soil Zn level

Research on the Preparation of Crosslinked Starch Chlorinated with Sodium Hypochlorite

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wuhan university Journal of Natural {2. 2003年第3A期8卷 861-865页

作者： Liang Yin, Zhu Zhi\|feng  college of Chemstry and Moleculcar sciences,{2., wuhan 430072, hubei, china wuhan university College of Chemstry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

Optimization of reaction variables such as catalyst type and amount, reaction temperature and time, formaldehyde amount, and oxidation extent of starch was studied for the crosslinking reaction of chlorinated cornstarch with formaldehyde. The reaction was carried out in aqueous suspension dispersed granular chlorinated cornstarch. Catalysts such as hydrochloric acid, sulfuric acid, and nitric acid were individually evaluated. The results show that the type and amount of the inorganic acid, formaldehyde amount, and oxidation extent of the chlorinated starch strongly affect the reaction efficiency. Hydrochloric acid shows the best catalyst effect on the reaction. Increasing the amount of the catalyst favourably raises the reaction efficiency. It is also demonstrated that the reaction efficiency is enhanced with the decrease of the oxidation extent of granular chlorinated starch.

关键词： chlorinated cornstarch crosslinking reaction formaldehyde

ZnSm_2._4稀土复合氧化物的结构与光谱学性质

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武汉大学学报（理学版） 2008年第6期54卷 641-644页

作者：张勇张克立武汉工程大学材料科学与工程学院湖北武汉430073 武汉大学化学与分子科学学院湖北武汉430072

报道了以流变相-先驱物法制备稀土复合氧化物ZnSm2.4的软化学方法.首先用流变相法合成了草酸盐先驱物,然后用差热分析(DTA)和热重分析(TG)研究了先驱物在空气中的热分解过程;用X射线粉末衍射和红外光谱表征了热分解固体产物;最后研究了Z... 详细信息

报道了以流变相-先驱物法制备稀土复合氧化物ZnSm2.4的软化学方法.首先用流变相法合成了草酸盐先驱物,然后用差热分析(DTA)和热重分析(TG)研究了先驱物在空气中的热分解过程;用X射线粉末衍射和红外光谱表征了热分解固体产物;最后研究了ZnSm2.4固体紫外-可见吸收光谱.结果表明,ZnSm2.4为尖晶石结构,晶胞参数a=0.92. 453 nm,晶胞体积V=0.782.38 nm3,化合物在紫外-可见范围内存在吸收.其中,2.6.2.nm为Sm3+—O2.电荷转移跃迁,而383.4,405.2.495.4 nm为Sm3+的4G5/2.7HJ/2.J=5,7,9)的电子跃迁.

关键词： ZnSm2.4 草酸盐先驱物流变相反应

Highly Sensitive Spectrofluorimetric Determination of Riboflavin Based on the Generation of Active Oxygen Coupled with Enzymatic Reaction

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wuhan university Journal of Natural {2. 2002年第3期7卷 361-364页

作者： Li Xiao\|yan 1,2., Wang Rui\|yong 1 , Cai Ru\|xiu 1  ,Liu zhi\|hong 1 1. college of chemistry and {2. sciences, wuhan university, wuhan 430072,hubei, china 2. Department of chemistry, Leshan Teacher s college, Leshan, 61 wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Leshan Teachers college Department of Chemistry Leshan Sichuan China (GRID:grid.459727.a) (ISNI:0000 0000 9195 8580) wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

A spectrofluorimetric method for the determining riboflavin (VB2. based on its enhancement on the fluorescence of hemoglobin-catalyzed enzymatic reaction was proposed. The proposed method consisted of two reactions. One was the photochemical reaction of VB2. the other was a hemoglobin-catalyzed enzymatic reaction. The optimal experimental conditions for the determinations were established. The linear range of the method was 5.0×10?9?1.0×10?7 mol/L of VB2. The detection limit was calculated to be 3.65×10?9 mol/L. The relative standard deviation of this method was 2.3%at 7.0×10?2.mol/L for 11 determinations.

关键词： Key words riboflavin spectrofluorimetric irradiation hemoglobin

Study of the Voltammetric Behavior of Heme and Its Direct Analysis Application

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wuhan university Journal of Natural {2. 1998年第4期3卷 473-475页

作者： Liu Huihong Ye Baoxian Zhou Xingyao(college of chemistry,{2., wuhan 430072, china) wuhan university College of Chemistry Wuhan China (GRID:grid.49470.3e) (ISNI:***)

The electroanalytical method of ferriheme was studied by linear sweep voltammetry in medium of 0.05 mol/L Tris+0.05 mol/L NH3?NH4Cl buffer at hang mercury drop electrodes (HMDE). Heme exhibits two pair reversible redox peaks and one irreversible peak. The cathodic peak potentials are?;0.2.6 V, ?0.42. V and ?1.408 V respectively. The first and the third peaks can be used for directly quantitative determination of heme concentrations. The peak currents are good linear relationship with heme concentration in ranges of 3×10?6–6×10?5 mol/L and 3×10?7–1.5×10?5 mol/L respectively.

关键词： heme voltammetric behavior catalytic wave

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BP人工神经网络用于除草剂活性预测

武汉大学学报（理学版） 2004年第4期50卷 411-414页

作者：胡耀垓李凯扬李伟胡继明武汉大学化学与分子科学学院

采用AM1方法研究了10种新型的磺酰脲类除草剂的电子结构,并以原子的Mulliken净电荷和除草剂在不同浓度(100,10mg/L)下对油菜、稗草两种作物的根、茎部位的抑制率为训练样本集,构造并训练得到具有活性预测能力的BP神经网络.结果表明,该B... 详细信息

采用AM1方法研究了10种新型的磺酰脲类除草剂的电子结构,并以原子的Mulliken净电荷和除草剂在不同浓度(100,10mg/L)下对油菜、稗草两种作物的根、茎部位的抑制率为训练样本集,构造并训练得到具有活性预测能力的BP神经网络.结果表明,该BP网络不仅能对训练样本很好拟合,亦能对未知化合物的活性作出很好的预测.

关键词：除草剂结构-活性关系预测 BP神经网络

Syntheses,characterization,crystal structure and magnetic properties of copper(Ⅱ) α,β-unsaturated carboxylate complexes with trimethyl phosphate

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Chinese Science Bulletin 2001年第12期46卷 987-991页

作者： WANG Yaoyu, LIU Ping, SHI Qian, GAO Yici & SHI Qizhen1. Department of chemistry, Northwest university, Xi’an 710069,{2. 2. Department of chemistry, Wenzhou Teachers college, Wenzhou 32.003,{2. 3. Department of chemistry, Lanzhou university, Lanzhou 730000,{2. Department of chemistry Northwest University Xi’an China Department of chemistry Wenzhou Teachers College Wenzhou China Department of chemistry Lanzhou University Lanzhou China

Two ternary complexes Cu2.4[OP(OCH3)3]2.(A represents CH2.CH-COO- and CH2.C(CH3)-COO-) have been synthesized, and elemental analyses, IR, ESR, electronic reflectance spectra and magnetic studies were carried out. The single crystal X-ray diffraction shows that Cu2.CH2.C(CH3)-COO]4[OP(OCH3)3]2.is triclinic, with space group P1, a = 1.0512.(13), b = 1.7559(5), c = 1.94479(3) nm, α =91.2.3(14)°,(β = 102.559(6)°,γ= 106.339(13)°, Z = 4 and R = 0.0668. Two copper(Ⅱ) atoms are bridged by four (a-methacrylate groups, and each copper(Ⅱ) atom is coordinated with a trimethyl phosphate molecule in the axial position, forming a distorted square pyramidal configuration. The symmetric center is between the two copper(Ⅱ) atoms, and the Cu-Cu bond distance is 0.2.098(6) nm. The Cu-Cu distance and magnetic studies suggest that there exist anti-ferromagnetic interactions between the two copper(Ⅱ) atoms.

关键词： copper(Ⅱ ) complex α β-unsaturated carboxylate trimethyl phosphate magnetic property crystal structure.

Crystal and molecular structure of 2.3-benzo-1,4,7,13-tetraoxa-10-selenacyclopentadeca-2.ene

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Chinese Journal of chemistry 1993年第5期11卷 401-405页

作者： XU,Han-Sheng LI,Wei-Ping LIU,Xiu-Fang Department of chemistry,wuhan {2.,wuhan 430072HUANG,You-Qing HU,Sheng-Zhi Department of chemistry,Xiamen {2.,Xiamen 361005 1Department of chemistry Wuhan University Wuhan 4300722Department of Chemistry Xiamen University Xiamen 361005

The crystal structure of 2.3-benzo-1,4,7,13-tetraoxa-10-selenacyclopentadeca-2.ene was de- termined,C_(14)H_(2.)O_4Se,M_r:331.2.,orthorhombic,Pbca,a=18.445(3),b=16.334(4),c9.2.2.2. ,V=2.81.3 ~3,Z=8,Dx=1.582.Mg m^(-3),λ(Mo K_α)=0.71073 ,μ=2..77 cm^(-1),F(000)=1360, T=2.7 K,R=0.032.,R_w=0.0438 for 2.92.reflections with I>3 σ(I).The crystal structure is closely related to that of benzo-15-crown-5(at 12. K),whereas the molecular geometry of the two coronands is different according to their torsion angles calculated and the shapes exhibited.

关键词： Crystal and molecular structure of 2 3-benzo-1 4 7 13-tetraoxa-10-selenacyclopentadeca-2.ene

Rheological Phase Synthesis and Characterization of Copper Monosalicylate

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wuhan university Journal of Natural {2. 2003年第2A期8卷 425-427页

作者： Yang Yi-yong, Li Liang-chao, Yuan Liang-jie, Sun Ju-tang, Zhang Ke-licollege of chemistry and {2. sciences, wuhan university, wuhan 430072, hubei, china wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

A new structural copper (II) monosalicylate, Cu(OC6H4C02.·H2., was synthesized by the rheological phase reaction method from salicylic acid and copper oxide in 1∶1 mole ratio. The structure was characterized by powder X-ray diffraction, IR and thermogravimetry. The Cu(OC6 H4 CC2.·H2. belongs to monoclinic system, with cell dimension:a=2.136 2.(67),b=0. 657 84(2.),c=l. 594 09(50) nm, β=108.434(2.) ,V=2.12. 2.(83) nm3,Z=12. Dcalc=2.041 kg·L?1,D obs=2.003 kg·L?1. The crystal water was lost at 96–2.0°C. The determined magnetic moment and magnetic susceptibility were 1. 947 B. M. and 6. 546×10?6 (2.7. 2. K), respectively.

关键词： copper monosalicylate rheological phase reaction crystal structure thermal decomposition infrared spectrum