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Effects of nitrogen content on growth and hydraulic characteristics of peach(Prunus persica L.) seedlings under different soil moisture conditions

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Journal of Forestry Research 2014年第2期25卷 365-375页

作者： Zhi-liang Zhang Guo-dong Liu fu-cang Zhang Cai-xia Zheng fu-quan ni Yin-hong Kang Yun Zeng College of Water Resource and Hydropower Sichuan University College of Information and Technology Sichuan Agricultural University Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest Sci-Tech University of Agriculture and Forestry

A pot experiment was conducted to investigate the effects of nitrogen content [Nl （no fertilizer）, N2 （0.15 ***-l）, and N3 （0.3 *** 1）] on the growth and the hydraulic characteristics of peach seedlings under different soil moisture conditions （Wl, W2 and W3, in which the soil water content was 45% to 55%, 60% to 70%, and 75% to 80% of the field water capacity, respectively） by using a specialized high pressure flow meter with a root chamber and a coupling, which was connected to plant organs. Leaf area and leaf hydraulic conductivity （KL） increased significantly in the seedlings because of increased soil moisture and N content. KL increased with leaf area. A linear correlation was documented between KL and leaf area. KL was higher in the morning and began to decline sharply after 16：00, at which KL declined after an initial increase. Soil moisture and N content enhanced shoot （Ks） and root （Kr） hydraulic conductivities, thereby improving the low soil moisture condition to a large extent. Ks and Kr of the seedlings were reduced by 32% and 27% respectively in N~, and by 14.7% and 9.4%, respectively in N2, and both in Wb compared with the control treatment. N3 had no significant effect on Ks and Kr under similar conditions. Linear negative correlations were observed between Kr and the excised root diameter as well as between Ks and the shoot stem diameter. The shoot-to-root ratio increased with in- crease in N content. The shoot-to-root ratio in N3 was increased by 14.37%, compared with N1 in W1 as well as by 12% and 4.39% in Wz and W3, respectively. Knowledge of the effects of soil moisture and N fertilizer on hydraulic characteristics and growth is important. Our results provide basic guidelines for the implementation of water-saving irrigation and fertilization management of nursery stock.

关键词： nitrogen Hydraulic conductivity growth WUE Prunus persica L.

Research on the Risk Associated with Rural Drinking Water Safety Based on Catastrophe Theory

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Journal of Water Resource and Protection 2011年第6期3卷 356-362页

作者： Chao Wang fu-quan ni Yu Deng Lin-Lin Jiang 不详

In this study, based on the analysis of the catastrophic risk of rural drinking water, with the representative villages in Ya’an as study objects and setting the four evaluation standards: water quality, water quantity, the Guarantee Probability for water Supply and the Convenience Level of the Access to Water Supply as the ba- sic framework, a Rural Drinking Water Safety Assessment was developed (RDWSA). Research showed that Catastrophe Theory was applicable in the RDWSA. Adding RDWSA based on Catastrophe Theory to the supportive system for decision-making in Ecological Hydrographic Management Decision Support System of Ya’an helped obtain the rank and results of RDWSE by the automatic calculation of programs, which could assist the risk assessment and risk management associated with rural drinking water in Ya’an.

关键词： Catastrophe Theory Risk Rural Drinking Water Safety Ya’an

年轻人不愿进入建筑业?——土木工程专业污名化现象及其消解进路

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高校辅导员学刊 2025年第1期17卷 49-55,69,98页

作者：付泉江西财经大学马克思主义学院江西南昌330013

随着材料行业崛起、房地产市场的持续低迷,通过污名化土木工程专业获取流量的现象呈现扩大化趋势,进而产生了报考率下降、从业人员信心不足等不良影响。当前,建筑业仍是中国经济的支柱,具有巨大的潜力。我们需要通过重构专业自信、提升... 详细信息

随着材料行业崛起、房地产市场的持续低迷,通过污名化土木工程专业获取流量的现象呈现扩大化趋势,进而产生了报考率下降、从业人员信心不足等不良影响。当前,建筑业仍是中国经济的支柱,具有巨大的潜力。我们需要通过重构专业自信、提升职业形象、树牢行业信心,帮助土木工程专业消解污名化,吸引更多有能力的有志青年加入建筑业,为中国的城市和社会进步作出贡献。

关键词：土木工程专业网络形象污名化建筑业

The Cotorsion Pair Cogenerated by the Subcategory of Stable functors in ((R-mod)^op, Ab)

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Algebra Colloquium 2019年第2期26卷 259-270页

作者： Xianhui fu Meiyuan ni School of Mathematics and Statistics Northeast Normal University Changchun 130024 China

Let R be an associative ring with identity. Denote by ((R-mod)^op, Ab) the category consisting of contravariant functors from the category of finitely presented left R-modules R-mod to the category of abelian groups Ab. An object in ((R-mod)^op, Ab) is said to be a stable functor if it vanishes on the regular module R. Let T be the subcategory of stable functors. There are two torsion pairs t1=(Gen(-,R),T)and t2=(T,F1), where 1 is the subcategory of ((R-mod)^op, Ab) consisting of functors with flat dimension at most 1. In this article, let R be a ring of weakly global dimension at most 1, and assume R satisfies that for any exact sequence 0 → M → N → K → 0, if M and N are pure injective, then K is also pure injective. We calculate the cotorsion pair (⊥T,(⊥T)⊥)cogenerated by T clearly. It is shown that G∈⊥T if and only if G/t1(G) is a projective object in T, i.e., G/t1(G)=(-,M) for some R-module M;and G∈(⊥T)⊥ if and only if G/t2(G) is of the form (-, E), where E is an injective R-module.

关键词： stable functors cotorsion pairs torsion pairs

Oxidation behavior of artificial magnetite pellets

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International Journal of Minerals,Metallurgy and Materials 2017年第6期24卷 603-610页

作者： Han-quan Zhang Jin-tao fu School of Resource and Civil Engineering Wuhan Institute of Technology Wuhan 430205 China Western Mining Company Xi’ning 810001 China

The oxidation behavior of artificial magnetite pellets was investigated through measurements of the oxidation degree and mineralogical analysis. The results show that artificial magnetite pellets are much easier to oxidize than natural magnetite. The oxidation is controlled through two different reaction mechanisms. The oxidation of artificial magnetite is dominated by internal diffusion, with an activation energy of 8.40 kJ/mol, at temperatures less than 800°C, whereas it is controlled by chemical reaction, with a reaction activation energy of 67.79 kJ/mol, at temperatures greater than 800°C. In addition, factors such as the oxygen volume fraction and the pellet diameter strongly influence the oxidation of artificial magnetite: a larger oxygen volume fraction and a smaller pellet diameter result in a much faster oxidation process.

关键词： artificial magnetite pellets oxidation reaction mechanisms

PRESSURE TRANSIENT ANALYSIS OF HETEROGENOUS RESERVOIRS WITH IMPERMEABILITY BARRIER USING PERTURBATION BOUNDARY ELEMENT METHOD

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Journal of Hydrodynamics 2005年第1期17卷 102-109页

作者： YINHong-jun HEYing-fu fuChun-quan DepartmentofPetroleumEngineering DaqingPetroleumInstituteDaqing163318China InstituteofPorousflowandFluidMechanics ChineseAcademyofSciencesLangfang065007China

The transient flow mathematical model of arbitrary shaped heterogeneous reservoirs with impermeability barrier is proposed in this paper. In order to establish this model, the perturbation method is employed and the solution of model is expanded into a series in powers of perturbation parameter. By using the Boundary Element Method (BEM) and Duhamel principle, wellbore pressure with effects of skins and wellbore storage is obtained. The type curves are plotted and analyzed considering effects of heterogeneity, arbitrary shape and impermeable barriers. Finally, the results obtained by perturbation boundary element method is compared with the analytical solution and is available for the transient pressure analysis of arbitrary shaped reservoirs.

关键词： heterogeneous reservoirs arbitrary shape impermeable barrier perturbation equation boundary element method pressure transient analysis type curves

Flow Characteristics of Deionized Water in Microtubes Absorbing Fluoro-Alkyl Silanes

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Chinese Physics Letters 2011年第10期28卷 150-153页

作者： QU Chao SONG fu-quan Department of Physics Zhejiang Normal University Jinhua 321004

In order to find the drag reduction mechanism of surface wettability,some experiments are carried out to research the flow of deionized water through *** flow rate of liquid through microtubes adsorbing Fluoro–Alkyl silanes(FAS)or not are *** inner diameters of the microtubes are 100µm,75µm and 50µm,*** relations of shear rate and slip velocity,and shear rate and slip length are *** inner surface wettability of the microtubes changes from hydrophilic at a contact angle of 23°to weak hydrophobic at a contact angle of 107°by adsorbing *** results indicate that the flow rate in microtubes adsorbing FAS is larger than those without FAS,the efficiency of drag reduction if about 13%,the slip velocity near the wall is proportional to the shear rate and the slip length remains invariant for different shear rates in microtubes with different diameters.

关键词： diameters inner flow

Inverse Problems for the Dirac Operator on a Star Graph

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Acta Mathematica Sinica,English Series 2023年第1期39卷 161-175页

作者： Dai quan LIU Chuan fu YANG School of Mathematics and Statistics Nanjing University of Science and TechnologyNanjing 210094P.R.China

Following the previous work,we shall study some inverse problems for the Dirac operator on an equilateral star *** is proven that the so-called Weyl function uniquely determines the ***,we pay attention to the inverse problem of recovering the potentials from the spectral data,which consists of the eigenvalues and weight matrices,and present a constructive *** basic tool in this paper is the method of spectral mappings developed by Yurko.

关键词： Inverse problem Dirac operator on graph Weyl function weight matrix

STUDY FOR STREAMLINE OF ARBITRARY SHAPED HOMOGENEOUS RESERVOIRS WITH IMPERMEABLE BARRIERS

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Journal of Hydrodynamics 2006年第3期18卷 329-333页

作者： YIN Hong-jun fu Chun-quan HE Ying-fu Key Laboratory of Enhanced Oil and Gas Recovery of Ministry of Education Daqing 163318 China Institute of Porous Flow and Fluid Mechanics CNPC and CAS Langfang 065007 China

The steady-state flow mathematical model of arbitrary shaped homogeneous reservoirs with impermeable barrier is constructed in this paper. By using Boundary Element Method （BEM）, the mathematical model is solved. And a streamline generating technique is presented. The figures of streamlines are plotted and analyzed considering the effect of complex boundary and impermeable barriers. Through analyzing it indicates that the size, shape and orientation of impermeable barriers have various degree of influence on the streamlines. So, if there are impermeable barriers in reservoir according to the geological materials, the influence of impermeable barriers must be considered when adjusting flood pattern and injection strategy.

关键词： Boundary Element Method (BEM) streamline,impermeable barrier mathematical model pressure