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Effect of Polyacrylamide Application on Runoff,Erosion,and Soil Nutrient Loss Under Simulated Rainfall

Pedosphere 2011年第5期21卷 628-638页

作者： WANG Ai-Ping LI fa-Hu YANG Sheng-min Inner mongolia Coal mine Design and Research Institute No. 55 Xinhua Road Hohhot 010010 (China) College of Water Conservancy and Civil Engineering China Agricultural University No. 17 Qinghua East Avenue Haidian District Beijing 100083 (China) State Key Laboratory of Soil Erosion and Dryland farming on the Loess Plateau No. 26 Xinong Road Yangling 712100 (China) Beijing Vocational College of Agriculture No. 5 Daotiannanli Changyang Town Beijing 102442(China)

Soil erosion affects soil productivity and environmental quality.A laboratory research experiment under simulated heavy rainfall with tap water was conducted to investigate the effects of anionic polyacrylamide(PAm) application rates(0,0.5,1.0,and 2.0 g m-2) and molecular weights(12 and 18 mg mol-1) on runoff,soil erosion,and soil nutrient loss at a slope of 5°.The results showed the two lower rates of PAm application decreased runoff while the highest rate increased runoff as compared with the *** concentration and soil mass loss increased significantly with the increasing PAm application *** with the control,PAm application decreased K+,NH4+,and NO3-concentrations in sediment and K+ and NH+4 concentrations in runoff,but significantly increased the mass losses of K+,NH4+,and NO-3 over soil surface except for the NH4+ at PAm application rate lower than 1.0 g *** application decreased the proportion of K+ loss with runoff to its total mass loss over soil surface from 60.1% to 16.4%.However,it did not affect the NH4+ and NO3-losses with runoff,and more than 86% of them were lost with runoff.A higher PAm molecular weight resulted in less soil erosion and K+ mass loss but had little effect on runoff and NH+4 and *** application did not prevent soil erosion and the mass losses of K+ and NO3-under experimental conditions.

关键词： application rate mass loss molecular weight nutrient concentration sediment concentration

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Decomposition mechanism of chromite in sulfuric acid–dichromic acid solution

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International Journal of minerals,metallurgy and materials 2017年第12期24卷 1361-1369页

作者： Qing Zhao Cheng-jun Liu Bao-kuan Li mao-fa Jiang Key Laboratory for Ecological metallurgy of multimetallic Ores(ministry of Education) Northeastern UniversityShenyang 110819China School of metallurgy Northeastern UniversityShenyang 110819China

The sulfuric acid leaching process is regarded as a promising, cleaner method to prepare trivalent chromium products from chromite; however, the decomposition mechanism of the ore is poorly understood. In this work, binary spinels of mg–Al, mg–Fe, and mg–Cr in the powdered and lump states were synthesized and used as raw materials to investigate the decomposition mechanism of chromite in sulfuric acid–dichromic acid solution. The leaching yields of metallic elements and the changes in morphology of the spinel were studied. The experimental results showed that the three spinels were stable in sulfuric acid solution and that dichromic acid had little influence on the decomposition behavior of the mg–Al spinel and mg–Fe spinel because mg^(2+), Al^(3+), and Fe^(3+) in spinels cannot be oxidized by Cr^(6+). However, in the case of the mg–Cr spinel, dichromic acid substantially promoted the decomposition efficiency and functioned as a catalyst. The decomposition mechanism of chromite in sulfuric acid–dichromic acid solution was illustrated on the basis of the findings of this study.

关键词： hydrometallurgy chromite sulfuric acid leaching spinel decomposition mechanism

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Ancient depletion signals in lherzolites from forearc region:Constraints from Lu-Hf isotope compositions

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Geoscience Frontiers 2022年第1期13卷 62-75页

作者： Yang Xu Chuan-Zhou Liu Wei Lin Xue-fa Shi Laboratory for marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China Key Laboratory of marine Geology and metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

The sub-arc mantle that experienced hydrous melting is commonly characterized by refractory geochemical compositions. Nevertheless, minor lherzolites with fertile compositions have also been reported for mantle peridotites from subduction zone. The petrogenesis and mantle source of the lherzolites are still controversial. The New Caledonia ophiolite(Peridotite Nappe) has been regarded as an allochthonous body of forearc lithosphere. This is supported by refractory compositions of its dominant mantle rocks.A few isolated lherzolitic massifs have also been observed in the northern part of New *** lherzolites are compositionally similar to abyssal peridotites, with negligible subduction-related modification. Here, we present new comprehensive geochemical compositions, in particular highprecision Sr-Nd-Hf isotope data, for the lherzolites. The initial^(176) Hf/^(177) Hf ratios display moderate correlations with sensitive indicators for the extent of melting(i.e., olivine Fo, whole-rock mg# and Yb contents in clinopyroxene) and whole-rock initial^(187) Os/^(188) Os ratios. Some samples have ancient radiogenic Hf isotopes and unradiogenic Os isotope compositions, implying the preservation of ancient depletion signals in the lherzolites. The Nd isotope compositions, together with trace elements and mineral micro-textures, suggest that the lherzolites have been overprinted by a recent melt-rock interaction event. The high equilibrium temperatures of the studied samples have been estimated by the twopyroxene REE thermometer, yielding temperatures of 1066–1315 ℃. The lherzolites have more depleted Nd-Hf isotope compositions and higher equilibrium temperatures than the New Caledonia *** indicates that the lherzolites may represent the residues of asthenosphere mantle trapped within the forearc region. Our studies on the New Caledonia lherzolites with ancient depletion signals suggest that ancient mantle domains in the convective mantle can be emplaced

关键词： New Caledonia ophiolite Forearc Lherzolites Sr-Nd-Hf isotopes Ancient melt depletion

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Evolution Behavior of γ-Al_(3.5)FeSi in mg melt and a Separation method of Fe from Al–Si–Fe Alloys

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Acta metallurgica Sinica(English Letters) 2018年第1期31卷 48-54页

作者： Tong Gao Zeng-Qiang Li Yao-Xian Zhang Xiang-fa Liu Key Laboratory for Liquid–Solid Structural Evolution and Processing of materials Ministry of Education Shandong University

The recycling of high Fe-content Al-Si alloys is a green industry. Eliminating the harmful effect of Fe, achieving the separation of Al and Fe is one of the key problems. Different from traditional methods for iron removal, a novel method using magnesium melt to separate Al and Fe is proposed. By introducing Al-14Si-5Fe alloy into mg melt, it was found that the γ-Al3.5FeSi phase evolves to Al3SiFe3.5 and Al5Fe2 through the melting and solidification process. Compared with the primary Al-rich γ-Al3.5FeSi phase, the formation of Fe-rich A13SiFe3.5 is quite beneficial for the separation of Al and Fe. mg-Si-Al and mg-Si-Fe alloys can be obtained at the top and bottom of the cooled ingot, respectively. The results in this study provide meaningful suggestions for recycling scrap Al-Si-Fe materials.

关键词： Al-Si-Fe mg melt Fe-rich phase evolution Separation

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Skeletal Rearrangement of Substituted Benzaldoxime 3-(2,2-Dichlorovinyl)-2,2-dimethyl Cyclo-propane Carboxylates under EI-mS

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Chemical Research in Chinese Universities 2004年第5期20卷 671-673页

作者： XIAYan HEShui-ji CHENQi-fa ZUOYu-min DepartmentofChemistry StateKeyLaboratoryofElemento-OrganicChemistry CentralLaboratoryofNankaiUniversity NankaiUniversityTianjin300071P.R.China

Introduction Substituted benzaldoxime 3-(2, 2-dichlorovinyl)-2,2-dimethyl cyclopropanecarboxylates,considered as pyrethroid analogs, show a good bioactivity such as fungicidal, herbicidal and plantgrowth regulating activities[1,2]. EI-mS spectra of those compounds show the rearrangement of their structures, which has prompted us to elucidate their behavior under EI conditions. All the compounds studied have m-165 and m-99 fragment ions in the EI-mS spectra, but there is no segment with the mass of 165 and 99 lost directly from the molecular ions. So we postulated the process of rearrangement, it involved the cleavage of the C2C3 bond in the substituted cyclopropyl accompanied by the migration of disubstitued methylene-amino moiety to C2 or C3 position and elimination of a conjugated group with the mass of 165 or 99 to afford the even electron ion, of which the important step is the cleavage of the N-O bond. Although the cleavage of the alkoxy bond in the pyrethroids[3-5] has been reported, there has been no rearrangement reported. In order to test our postulations, mIKES and EI-HR-mS were carried out to elucidate the fragmentation pathways. The substituents in the phenyl ring played important roles in the stabilization of the product ions. The focal point of our work was to investigate two pathways of the skeletal rearrangement and the effect of the substituents.

关键词： Substituted benzaldoxime carboxylate EI-mS mIKES EI-HR-mS Skeletal rearrangement

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Soil Erosion as Affected by Polyacrylamide Application Under Simulated Furrow Irrigation with Saline Water

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Pedosphere 2012年第5期22卷 681-688页

作者： DOU Chao-Yin LI fa-Hu L.S.WU College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083(China) State Key Laboratory of Soil Erosion and Dryland farming on Loess Plateau Yangling 712100(China) Department of Environmental Sciences University of CaliforniaRiverside 92521(USA)

The reduction of soil and water losses under furrow irrigation with saline water is important to environmental protection and agricultural production. The objective of this study was to determine the effect of polyacrylamide (PAm) application on soil infiltration and erosion under simulated furrow irrigation with saline water. Polyacrylamide was applied by dissolving it in irrigation water at the rates of 1.5, 7.5, and 15.0 mg L-1 or spreading it as a powder on soil surface at the rates of 0.3, 1.5, 3.0, and 6.0 g m-2, respectively. The electrolyte concentration of tested irrigation water was 10 and 30 mmolc L-1 and its sodium adsorption ratio (SAR) was 0.5, 10.0, and 20.0 (mmolc L-1)0.5. Distilled water was used as a control for irrigation water quality. Results indicated that the electrolyte concentration and SAR generally did not significantly affect soil and water losses after PAm application. Infiltration rate and total infiltration volume decreased with the increase of PAm application rate. Polyacrylamide application in both methods significantly reduced soil erosion, but PAm application rate did not significantly affect it. The solution PAm application was more effective in controlling soil erosion than the powdered PAm application, but the former exerted a greater adverse influence on soil infiltration than the latter. Under the same total amounts, the powdered PAm application resulted in a 38.2%-139.6% greater infiltration volume but a soil mass loss of 1.3-3.4 times greater than the solution PAm application.

关键词： electrolyte concentration sodium adsorption ratio soil infiltration soil loss water loss

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Differentiation in cranial variables among six species of Hylopetes(Sciurinae: Pteromyini)

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Zoological Research 2013年第S5期34卷 I0012-I0019页

作者： Song LI fa-Hong YU Kunming Natural History museum of Zoology Kunming Institute of Zoology Chinese Academy of Sciences State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences ICBR University of FloridaGainesville

There is some discrepancy in the classification of different species of Hylopetes, particularly regarding systematic status of H. electilis and H. phayrei and their relationship to other species. In the present study, for the first time we have brought together six of the nine Hylopetes species and performed statistical analysis of 14 measurable cranial variables, analyzing in total 89 specimens, including H. electilis, H. alboniger, H. phayrei, H. lepidus, H. spadiceus, and H. nigripes. Both univariate and multivariate analysis results indicate that H. electilis can not only be obviously distinguished from H. phayrei, but also clearly differs from the other four Hylopetes species. These results sustain the contention that H. electilis is neither a synonym nor subspecies ofH. phayrei, but should be considered a distinct and valid species. Subsequently, a straightforward discussion on the biogeography of Hylopetes in southeastem Asia gives further insight into the differentiation and variety of species belonging to this genus.

关键词： Hylopetes morphology Cranial variables Statistical analysis Species

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Effects of Different Oxidants on HCl-based Pickling Process of 430 Stainless Steel

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Journal of Iron and Steel Research International 2016年第8期23卷 778-783页

作者： Qiong XIE Pei-yang SHI Cheng-jun LIU mao-fa JIANG Key Laboratory for Ecological metallurgy of multimetallic mineral of ministry of Education Northeastern University

To shorten the time required for the pickling process and to enhance the quality of ferritic stainless steel plates,the effects of oxidants including hydrogen peroxide（H2O2）,potassium permanganate（KmnO4）,and potassium chlorate（KClO3）on the pickling behavior in HCl-based electrolyte as well as the surface quality of hot-rolled and blasted 430 stainless steel（430-SS）were *** were conducted using mass-loss tests,microstructure analyses,potentiodynamic polarization curves,and electrochemical impedance spectroscopy *** results showed that the addition of oxidants substantially accelerated the pickling process of 430-SS by enhancing the cathodic reaction rate and reducing the charge transfer *** electrolytes comprising 5-8mass% HCl at a temperature of 40-60 ℃ and at the same concentration within the range from 0to 2mass%,H2O2 was demonstrated to be superior to KmnO4 and KClO3in accelerating the pickling *** surface quality of 430-SS pickled in the presence of H2O2 was better than those of specimens pickled in the presence of KmnO4 and KClO3 when the removal of the oxide layer,intergranular corrosion,and surface roughness were collectively *** 1mass% H2O2 was added,the mass loss rate of 430-SS was increased by 629%and no residual oxide layer or intergranular corrosion was observed on the surface of the steel;in addition,the roughness was only 1.7μm.H2O2 was determined to be a better oxidant than KmnO4 and KClO3 when the pickling process,surface quality,solution recycling,and environment protection were considered as a whole.

关键词： roughness cathodic electrolyte impedance stainless potassium recycling oxidant accelerating immersed

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The Necessary and Sufficient Conditions for a Universal Conservation of a State of a Unitary Quantum Circuit

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Communications in Theoretical Physics 2002年第7期38卷 31-34页

作者： LI Da-fa LI Xin-Xin HUANG Hong-Tao Department of mathematics Tsinghua University Beijing 100084 China Department of Computer Science Wayne State University Detroit MI 48202 USA Electrical Engineering and Computer Science Department University of Michigan Ann Arbor MI 48109 USA

By A. Peres and A. Stern's opinions a computational process evolves along a cyclic logic orbit defined by a computation. A. Stern thought that if we could design such a circuit, its operations can be extended to including nonconservative behavior associated with the external perturbations or internal quantum errors. A. Peres did not discuss how to make φm-1 ＝φo. A. Stern proposed only a necessary condition for a conservation of a state of a quantum *** this paper we present a necessary and sufficient condition for a universal conservation of a state of a quantum *** also find all operators which can allow the conservation.

关键词： logic operators, matrix logic, quantum circuits

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Highly active catalyst for vinyl acetate synthesis by modified activated carbon

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Chinese Chemical Letters 2009年第7期20卷 865-868页

作者： Chun Yan Hou Liang Rong Feng fa Li Qiu Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China The Graduate School of Chinese Academy of Science Beijing 100049 China

A new zinc acetate catalyst which was prepared from modified activated carbon exhibited extreme activity towards the synthesis of vinyl acetate. The activated carbon was modified by nitric acid, vitriol and peroxyacetic acid （PAA）. The effect on specific area, structure, pH and surface acidity groups of carders by modification was discussed. Amount of carbonyl and carboxyl groups in activated carbon was increased by peroxyacetic acid treatment. The productivity of the new catalyst was 14.58% higher than that of catalyst prepared using untreated activated carbon. The relationship between amount of carbonyl and carboxyl groups （m） and catalyst productivity （P） was P = 1.83 ＋ 2.26 × 10^-3＊e^3.17m. Reaction mechanism was proposed. C 2009 Liang Rong Feng. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Surface acidic groups Peroxyacetic acid Activated carbon Catalyst for vinyl acetate synthesis

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