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Nitrification inhibitor nitrapyrin does not affect yield-scaled nitrous oxide emissions in a tropical grassland

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pedosphere 2021年第2期31卷 265-278页

作者： Ana Gabriela pÉREZ-CASTILLO Cristina CHINCHILLA-SOTO Jorge Alberto ELIZONDO-SALAZAR Ronny BARBOZA Dong-Gill KIm Christoph mÜLLER Alberto SANZ-COBENA Azam BORZOUEI Khadim DAWAR mohammad ZAmAN Environmental pollution Research Center(CICA) University of Costa RicaMontes de Oca 11501(Costa Rica) Alfredo Volio mata Experimental Station University of Costa RicaOchomogo 30304(Costa Rica) Wondo Genet College of Forestry and Natural Resources Hawassa UniversityP.O.Box 128Shashemene(Ethiopia) Institute of plant Ecology Justus Liebig University GiessenHeinrich-Buff Ring 26Giessen 35392(Germany) School of Biology and Environmental Science University College DublinBelfieldDublin 4(Ireland) Research Center for the management of Environmental and Agricultural Risks(CEIGRAm) Department of Chemistry and Food Technology(ETSIAAB)Universidad Politécnica de MadridMadrid 28040(Spain) Nuclear Agriculture Research School Nuclear Science and Technology Research Institute(NSTRI)Karaj 31465-1498(Iran) Department of Soil and Environmental Sciences The University of AgriculturePeshawar 25000(Pakistan) Soil and Water management&Crop Nutrition Section Joint Food and Agriculture Organization(FAO)/International Atomic Energy Agency(IAEA)Division of Nuclear Techniques in Food and AgricultureDepartment of Nuclear Sciences and ApplicationsIAEAVienna International CentreP.O.Box 100Vienna 1400(Austria)

Urea is the most common nitrogen(N)fertilizer used in the tropics but it has the risk of high gaseous nitrogen(N)*** of nitrification inhibitor has been suggested as a potential mitigation measure for gaseous N losses in N fertilizer-applied *** a field trial on a tropical Andosol pastureland in Costa Rica,gaseous emissions of ammonia(NH_(3))and nitrous oxide(N_(2)O)and grass yield were quantified from plots treated with urea(U;41.7 kg N ha^(-1)application^(-1))and urea plus the nitrification inhibitor nitrapyrin(U+NI;41.7 kg N ha^(-1)application^(-1)and 350 g of nitrapyrin for each 100 kg of N applied)and control plots(without U and NI)over a six-month period(rainy season).Volatilization of NH_(3)(August to November)in U(7.4%±1.3%of N applied)and U+NI(8.1%±0.9%of N applied)were not significantly different(p>0.05).Emissions of N_(2)O in U and U+NI from June to November were significantly different(pmission in U+NI was higher than that in *** and crude protein production of grass were significantly higher(pplots,but they were not significantly different between U and U+*** was no significant difference in yield-scaled N_(2)O emission between U(0.31±0.10 g N kg^(-1)dry matter)and U+NI(0.47±0.10 g N kg^(-1)dry matter).The results suggest that nitrapyrin is not a viable mitigation option for gaseous N losses under typical N fertilizer application practices of pasturelands at the study site.

关键词： ammonia volatilization Andosol Costa Rica field trial gaseous N loss greenhouse gas emission urea

Thermoelastic Analysis of Non-uniform pressurized Functionally Graded Cylinder with Variable Thickness Using First Order Shear Deformation Theory(FSDT) and perturbation method

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Chinese Journal of mechanical Engineering 2015年第6期28卷 1149-1156页

作者： KHOSHGOFTAR m J mIRZAALI m J RAHImI G H Faculty of mechanical Engineering Tarbiat Modares University Department of mechanical Engineering Faculty of Engineering Arak University Department of mechanical Engineering Politecnico di Milano

Recently application of functionally graded materials（FGms） have attracted a great deal of interest. These materials are composed of various materials with different micro-structures which can vary spatially in FGms. Such composites with varying thickness and non-uniform pressure can be used in the aerospace engineering. Therefore, analysis of such composite is of high importance in engineering problems. Thermoelastic analysis of functionally graded cylinder with variable thickness under non-uniform pressure is considered. First order shear deformation theory and total potential energy approach is applied to obtain the governing equations of non-homogeneous cylinder. Considering the inner and outer solutions, perturbation series are applied to solve the governing equations. Outer solution for out of boundaries and more sensitive variable in inner solution at the boundaries are considered. Combining of inner and outer solution for near and far points from boundaries leads to high accurate displacement field distribution. The main aim of this paper is to show the capability of matched asymptotic solution for different non-homogeneous cylinders with different shapes and different non-uniform pressures. The results can be used to design the optimum thickness of the cylinder and also some properties such as high temperature residence by applying non-homogeneous material.

关键词： non-homogenous cylinder First order Shear Deformation Theory matched asymptotic method perturbation method functionally graded material

posterior Urethral Valves without Reflux Associated with Bilateral Renal Cortical Atrophy: Diagnosis and management

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Open Journal of pediatrics 2023年第6期13卷 791-797页

作者： Bangoura Kaba Kolie Ouo-Ouo Camara Salematou Hassimiou Bangoura m’mah Aminata Camara Emmanuel Diallo mohamed Lamine Diallo Fatoumata Binta Diop mamadou moustapha Kouyate moustapha Beimy pé pediatrics Department CHU Donka Conakry Guinea Gamal Abdel Nasser University of Conakry Conakry Guinea Institute of Nutrition Conakry Guinea

The objective of this case report was to highlight the characteristics of posterior urethral valves observed in a 3-year-old patient and to describe their management. The case of a 4-year-old patient treated for a posterior urethral valve with bilateral renal cortical atrophy was reviewed. The diagnosis was confirmed by abdominal ultrasound, cystography and abdominal CT. He was referred to martinique (a tertiary health establishment) for effective support. From the acute situation to the fortuitous discovery, its understanding must be deepened because of the potential immediate symptomatic impact in the form of renal colic which can be associated with sepsis, as well as in the long term on renal function. This observation is intended to help the attending physician to initiate his diagnosis and treatment.

关键词： Valves Urethra posterior

Evaluation of a mathematical model using experimental data and artificial neural network for prediction of gas separation

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Journal of Natural Gas Chemistry 2008年第2期17卷 135-141页

作者： m.peer m.mahdyarfar T.mohammadi Research Center for membrane processes Department of Chemical EngineeringIran University of Science and TechnologyNarmakTehranlran Gas Division Research Institute of Petroleum IndustryTehranIran

In recent times, membranes have found wide applications in gas separation processes. As most of the industrial membrane separation units use hollow fiber modules, having a proper model for simulating this type of membrane module is very useful in achieving guidelines for design and characterization of membrane separation units. In this study, a model based on Coker, Freeman, and Fleming＇s study was used for estimating the required membrane area. This model could simulate a multicomponent gas mixture separation by solving the governing differential mass balance equations with numerical methods. Results of the model were validated using some binary and multicomponent experimental data from the literature. Also, the artificial neural network （ANN） technique was applied to predict membrane gas separation behavior and the results of the ANN simulation were compared with the simulation results of the model and the experimental data. Good consistency between these results shows that ANN method can be successfully used for prediction of the separation behavior after suitable training of the network

关键词： hollow fiber membrane gas separation mathematical modeling artificial neural network

中华人民共和国合同法附最高人民法院关于适用《中华人民共和国合同法》司法解释

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Thermo-magnetic analysis of thick-walled spherical pressure vessels made of functionally graded materials

作者：孙新强 (澳)m. p.·Ellinghaus (澳)E. W.·Wright编译

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Applied mathematics and mechanics(English Edition) 2019年第6期40卷 751-766页

作者： m. A. NEmATOLLAHI A. DINI m. HOSSEINI Department of Biosystems Engineering College of AgricultureShiraz UniversityShiraz 71441-65186Iran Department of mechanical Engineering Ferdowsi University of MashhadMashhad 91775-1111Iran Department of mechanical Engineering Sirjan University of TechnologySirjan 78137-33385Iran

This study presents an analytical solution of thermal and mechanical displacements, strains, and stresses for a thick-walled rotating spherical pressure vessel made of functionally graded materials (FGms). The pressure vessel is subject to axisymmetric mechanical and thermal loadings within a uniform magnetic field. The material properties of the FGm are considered as the power-law distribution along the thickness. Navier’s equation, which is a second-order ordinary differential equation, is derived from the mechanical equilibrium equation with the consideration of the thermal stresses and the Lorentz force resulting from the magnetic field. The distributions of the displacement, strains, and stresses are determined by the exact solution to Navier’s equation. Numerical results clarify the influence of the thermal loading, magnetic field, non-homogeneity constant, internal pressure, and angular velocity on the magneto-thermo-elastic response of the functionally graded spherical vessel. It is observed that these parameters have remarkable effects on the distributions of radial displacement, radial and circumferential strains, and radial and circumferential stresses.

关键词： analytical solution magnetic field thermal loading rotating thick-walled spherical pressure vessel functionally graded material (FGm)

Instability inspection of parametric vibrating rectangular mindlin plates lying on Winkler foundations under periodic loading of moving masses

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Acta mechanica Sinica 2019年第1期35卷 242-263,I0007页

作者： E.Torkan m.pirmoradian m.Hashemian Young Researchers and Elite Club Khomeinishahr Branch Islamic Azad UniversityKhomeinishahrIsfahan 84175-119Iran Department of mechanical Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIsfahan 84175-119Iran

parametric resonance is one of the most important issues in the study of dynamical behavior of structures. In this paper, dynamic instability of a moderately thick rectangular plate on an elastic foundation is investigated in the case of parametric and external resonances due to periodic passage of moving masses. The governing coupled partial differential equations (pDEs) of the system, with consideration of the first-order shear deformation theory (FSDT) or mindlin plate theory, are presented and they are reduced to a set of ordinary differential equations (ODEs) with time-dependent coefficients using the Galerkin procedure. All inertial components of the moving masses are adopted in the dynamical formulation. Instability survey is carried out for three different loading trajectories considerably interested in many practical applications of the issue, i.e. rectilinear, diagonal and orbiting trajectories. In order to analyze the resonance conditions, the incremental harmonic balance (IHB) method is introduced to calculate instability boundaries, as well as external resonance curves in parameters plane. A comprehensive study is done to assess effects of thickness ratio and foundation stiffness on the resonance conditions. It is found that an increase in the plate's thickness ratio leads to a reduction in values of critical parameters. moreover, it is observed that in creasing the foundation stiffness moves the in stability regions and resona nee curves to higher frequencies of the moving masses and also leads to further stability of the parametrically excited system at lower frequencies. Time response simulations done via Runge-Kutta method confirmed the results predicted by IHB method.

关键词： mass-plate interaction mindlin plate parametric resonance External resonance Incremental harmonic balanee method

从铜渣中获得工业醋酸铜(Ⅱ)溶液的常压浸出条件和浸出动力学研究

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中南大学学报:英文版 2023年第8期30卷 2556-2573页

作者： Zeynel Abidin SARI m.Deniz TURAN Department of metallurgy-Iskenderun Vocational School of Higher Education Iskenderun Technical UniversityHatay 31200Turkey Department of metallurgy and materials Engineering Fırat UniversityElazığ23119Turkey

从铜渣中回收有价金属的技术虽然很多,但其经济和环境相容性都不理想。用双氧水和有机酸乙酸研究了铜渣中金属在常压下的溶解行为。该渣为转炉渣和闪速炉渣的混合物,含Cu 6.74%,Zn 4.34%,Fe 36.45%。常规的常压浸出实验在100 mL的玻璃... 详细信息

从铜渣中回收有价金属的技术虽然很多,但其经济和环境相容性都不理想。用双氧水和有机酸乙酸研究了铜渣中金属在常压下的溶解行为。该渣为转炉渣和闪速炉渣的混合物,含Cu 6.74%,Zn 4.34%,Fe 36.45%。常规的常压浸出实验在100 mL的玻璃烧杯中进行,在磁力搅拌器中使用涂有聚四氟乙烯的磁性搅拌棒。在最佳浸出条件下,铜提取率为98.04%,锌提取率为28.8%,铁提取率为2%。拉曼光谱显示Cu^(2+)/Zn^(2+)与AcO^(-)(乙酸)存在配位。溶解过程用一级动力学方程描述。表观活化能为23.7 kJ/mol,表明溶解过程受扩散控制。H_(2)O_(2)和CH_(3)COOH的反应级数分别为1.24和0.1。本文提出的湿法冶金新工艺简单、环保,在常规条件下从铜渣中获得醋酸铜溶液的性能明显优于其他方法。

关键词：铜渣醋酸铜溶液选择性浸出过氧化氢醋酸

Two-fluid modeling of Geldart A particles in gas-fluidized beds

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particuology 2008年第6期6卷 540-548页

作者： m.A. van der Hoef J.A.m. Kuipers Faculty of Science & Technology University of Twente

We have investigated the effect of cohesion and drag models on the bed hydrodynamics of Geldart A particles based on the two-fluid （TF） model. For a high gas velocity U0 = 0.03 m/s, we found a transition from the homogeneous fluidization to bubbling fluidization with an increase of the coefficient C1, which is used to account for the contribution of cohesion to the excess compressibility. Thus cohesion can play a role in the bed expansion of Geldart A particles. Apart from cohesion, we have also investigated the influence of the drag models. When using the Wen and Yu drag correlation with an exponent n = 4.65, we find an under-prediction of the bed expansion at low gas velocities （U0 = 0.009 m/s）. When using a larger exponent （n = 9.6）, as reported in experimental studies of gas-fluidization, a much better agreement with the experimental bed expansion is obtained. These findings suggest that at low gas velocity, a scale-down of the commonly used drag model is required. On the other hand, a scale-up of the commonly used drag model is necessary at high gas velocity （U0 = 0.2 and 0.06 m/s）. We therefore conclude that scaling the drag force represent only an ad hoc way of repairing the deficiencies of the TF model, and that a far more detailed study is required into the origin of the failure of the TF model for simulating fluidized beds of fine powders.

关键词： Gas-fluidized bed Geldart A particles Two-fluid model Cohesive force Drag correlation