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101.
Nutrient Cycling in Agroecosystems - Adoption of appropriate agronomic practices, such as optimum seeding and nitrogen (N) rates, in synchronization with proper water management practice could help...  相似文献   
102.
ZnSO4·7H2O is modified by impregnation method with zeolite matrices (13X-zeolite and LTA-zeolite) to improve its hydration performance. Water sorption ability of composites was carried out in a constant temperature and humidity environment. Composite of ZnSO4/13X-zeolite showed highest water sorption (0.26 g/g) at 75% relative humidity under 45°C air temperature, which is double than pure ZnSO4·7H2O. This is due to larger surface area (491 m2 g-1) and pore volume (0.31 cm3). Furthermore, both hydration rate and adsorption mass depends on relative humidity and hydration temperature. However, if the air temperature and the relative humidity are higher than 45°C and 75% RH, the hydration ability of the composite material is significantly reduced. Besides, X-ray measurements of composite (ZnSO4/13X) revealed that sorption/desorption process, crystallinity and phase of partially hydrated ZnSO4 remain the same, which enhance the adsorption mass and enthalpy during the hydration process.  相似文献   
103.
Since the discovery of superconductivity at temperatures above the technologically promising liquid nitrogen temperatures, applications based on superconductors have expanded and are being put to commercial use. However, superconductivity at higher temperatures typically occurs in complex materials requiring stringent material and environmental constraints. Such restraints make the realization and integration of these materials with normal materials a nontrivial aspect. In this progress report, unique features of these superconductors in terms of their synthesis, physical properties determining interface electrical transport, and their applications are discussed. A detailed progress report on these applications with remarks on efforts taken to integrate these devices with traditional platforms and semiconducting materials is provided.  相似文献   
104.
The likelihood of developing cancer during one's lifetime is approximately one in two for men and one in three for women in the United States. Cancer is the second-leading cause of death and accounts for one in every four deaths. Evidence-based policy planning and decision making by cancer researchers and public health administrators are best accomplished with up-to-date age-adjusted site-specific cancer death rates. Because of the 3-year lag in reporting, forecasting methodology is employed here to estimate the current year rates based on complete observed death data up through three years prior to the current year. The authors expand the State Space Model (SSM) statistical methodology currently in use by the American Cancer Society (ACS) to predict age-adjusted cancer death rates for the current year. These predictions are compared with those from the previous Proc Forecast ACS method and results suggest the expanded SSM performs well.  相似文献   
105.
This investigation describes the peristaltic motion of a magnetohydrodynamic (MHD) Oldroyd‐B fluid with heat and mass transfer. An incompressible Oldroyd‐B fluid is considered in a channel with flexible walls. The relevant equations are developed by employing equations of continuity, momentum, energy, and concentration. Expressions of stream function, temperature, concentration field, and heat transfer coefficient are presented when the wave number is small. The obtained solutions are graphically discussed for the several interesting parameters entering into the problem. It is found that relaxation and retardation times have opposite effects on the size of the trapped bolus. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20380  相似文献   
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The influence of Hall currents and rotation on the oscillatory flows of an infinite plate is investigated. Exact solutions for the two problems are obtained.The fluid considered is a homogeneous Oldroyd-B. During the mathematical analysis it is found that governing differential equation for steady flow in an Oldroyd-B fluid is identical to that of viscous fluid. Further, it is observed that in absence of the strength of transverse magnetic field (B0) the solution in resonance case does not satisfy the boundary condition at infinity. Physical significance of mathematical results is also discussed.  相似文献   
109.
This study investigates the thermal-diffusion and diffusion-thermo effects on the two-dimensional magnetohydrodynamics (MHD) axisymmertric flow of a second grade fluid. Mathematical analysis has been carried out in the presence of Joule heating and first order chemical reaction. Using momentum, energy and concentration laws, the governing partial differential equations have been reduced to the ordinary differential equations by suitable transformations. Series solutions are constructed by homotopy analysis method (HAM). Convergence of the derived series solutions is ensured. Plots are displayed in order to examine the influence of emerging parameters on the dimensionless components of velocity, temperature and concentration fields. Numerical computations for skin friction coefficient, Nusselt number and Sherwood number are tabulated.  相似文献   
110.
A linear minimum mean-square error (LMMSE) equalizer for avalanche-photodiode (APD) based integrate-and-dump receivers is designed to compensate for intersymbol-interference (ISI) introduced by the APD's random impulse response. Recent work on the characterization of the joint probability distribution of the APD's gain and buildup-time are adopted and utilized to determine the mean and correlation matrix of the APD-based receiver's random impulse response. This LMMSE equalizer is shown to improve the bit-error-rate dramatically at high transmission rates, resulting in an improvement in the receiver sensitivity by approximately 2.3 dB at 15 GHz.  相似文献   
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