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71.
Selecting Agricultural Best Management Practices for Water Conservation and Quality Improvements Using Atanassov’s Intuitionistic Fuzzy Sets 总被引:2,自引:0,他引:2
Improper agricultural practices can affect ground water through leaching, surface water through runoff, algae infestations,
deforestation, and air quality through burning operations and ammonia emissions. These effects may be mitigated through the
institution of best management practices. The utility of best management practices (BMPs) is recognized and being actively
promoted by agricultural agencies; however, identifying a set of mandatory BMPs is inappropriate given variations between
climactic, demographic and geographic regions as well as differences in farming practices. In this study, a multi-criteria
decision making model based on Attanassov’s Intuitionistic Fuzzy Set (A-IFS) theory is introduced and its utility to rank
agricultural best management practices is illustrated using a case-study from South Texas. Implementation of the A-IFS MCDM
method to the South Texas region resulted in “irrigation scheduling” being ranked as the most preferred alternative, while
“brush control/management” was the least preferred. The A-IFS MCDM approach was particularly suitable for prioritizing and
ranking agricultural best management practices because decision makers often tend to have both likes and dislikes with regards
to specific BMPs and for a given evaluation attribute. Not only does the A-IFS MCDM method provide a single composite score
to rank the BMP alternatives, but the output of the A-IFS MCDM method also includes upper and lower bounds that help identify
the uncertainties in the decision making process. 相似文献
72.
Jiang‐Ping Wu Anjan K. Saha Nizar Haddad Carl A. Busacca Jon C. Lorenz Heewon Lee Chris H. Senanayake 《Advanced Synthesis \u0026amp; Catalysis》2016,358(12):1924-1928
A simple N‐heterocyclic carbene (NHC) derived from 1‐methyl‐3‐ethylimidazolium tetrafluoroborate was found to be an efficient ligand for a range of copper‐catalyzed cross‐coupling reactions, leading to the formation of aromatic ethers and thioethers.
73.
Restrained steel beams, when exposed to fire, develop significant restraint forces and often behave as beam-columns. The response
of such restrained steel beams under fire depends on many factors including: fire scenario, beam slenderness ratio, location
of axial restraint at the supports, and high-temperature properties of steel. A set of numerical studies, using finite element
computer program ANSYS, is carried out to study the fire response of steel beam-columns under realistic fire and restraint
scenarios. Results from the parametric studies indicate that fire scenario, beam slenderness, location of axial restraint
and high-temperature creep have significant influence on the behavior of restrained beams under fire conditions. Severe fires
produce high axial forces at early stages of fire exposure; whereas in moderate fires, significant axial force develops only
at later stages of fire exposure. Axial restraint enhances the fire resistance due to the development of tensile catenary
action in restrained beams. Furthermore, restrained beams with low slenderness ratio exhibit better fire performance when
the axial restraint at the support is located at the bottom flange. 相似文献
74.
Performance Assessment of a New Radiation Microsensor Based 4H-SiC trench MOSFET: A Simulation Study
Silicon - The MOSFET has been widely used as a detector for high-energy radiations in areas like nuclear energy and medical treatments. Generally, the shift in threshold voltage of the... 相似文献
75.
In the present work, the shell and tube heat exchanger (STHX) is designed based on The Tubular Exchanger Manufacturers Association standards with hot fluid (water) flowing on the shell side and cold fluid on the tube side. A comparison is made between the Nusselt number and friction factor obtained from numerical and experimental results of segmental baffles (SBs) and helical baffles (HB) with different baffle inclinations. The results show that SB provided a higher Colburn factor (js) when compared with HBs STHXs (20°, 30°, 40°, and 50°), but shell side pressure drop is lower for 40° HBs STHXs for the same shell side fluid flow rates. 相似文献
76.
77.
Modulation of stability properties of bovine trypsin after in vitro structural changes with a variety of chemical modifiers 总被引:4,自引:0,他引:4
Controlled chemical modification of enzymes, targeting groups not involved
in the active site, can lead to modified catalysts that are intrinsically
more efficient and resistant to heat and denaturing agents. Bovine
pancreatic trypsin was covalently modified up to 75-85% with monomeric
glutaraldehyde (MGA), polymeric glutaraldehyde (PGA), oxidized sucrose and
oxidized sucrose polymers (OSP 70 and OSP 400). Virtually no loss in
activity occurred upon modification. Temperature optima of trypsin shifts
from 45-76 degrees C and T50 from 54-76 degrees C for the best modified
sample made with OSP. The efficiency of the modifiers in stabilization was
ranked in the order: OSP 400-T > OSP 70-T > PGA-T > MGA-T >
Sucrose-T. Half-life of modified enzymes also followed the same trend. Both
stabilization factor and t1/2 decreased with increasing temperatures. The
free energy of activation for inactivation delta(deltaG*) varies from 12-20
kJ/mol and the activation enthalpy delta(deltaH*) of the modified trypsin
by 80-120 kJ/mol indicating stabilization. Inactivation of modified trypsin
by urea is less noticeable. The character of the two-step inactivation
process of trypsin changes with the degree of stabilization in that the
duration of phase I one increased noticeably as stabilization increases.
Native trypsin fluoresces less intensely showing a red shift under the
influence of denaturation. Such a fluorescence change is not so obvious for
the modified enzymes indicating conformational stability acquired by
modification.
相似文献
78.
Shahram Emami Venkatesh Meda Robert T. Tyler 《International Journal of Food Science & Technology》2011,46(2):421-428
The effect of micronisation (high‐intensity infrared heating) and microwave radiation of normal barley (NB), high‐amylose barley (HAB) and waxy barley (WB) on the physical and mechanical properties was studied. Samples were tempered to 42–45% moisture content and then subjected to infrared or microwave radiation to reduce the moisture content to approximately 10%. The grain surface temperature during radiation was maintained at 100 °C. The changes in physical and mechanical properties were compared with unprocessed samples. Thermal radiation increased slightly the volume of the kernels because of the diffusion of water vapour from inside to the outer surface. These changes resulted in a decrease in particle and bulk densities. Thermal radiation affected the Hunter colour values, as well. The mechanical properties including bio‐yield point, modulus of elasticity and breakage susceptibility were affected by micronisation and microwave heating. 相似文献
79.
Suddhasattwa Ghosh S. Vandarkuzhali Nibedita Gogoi P. Venkatesh G. Seenivasan B. Prabhakara Reddy K. Nagarajan 《Electrochimica acta》2011,(24):8204
The anodic dissolution of U and Zr metal was studied in LiCl–KCl–UCl3 and LiCl–KCl–ZrCl4, respectively, at 773 K by cyclic voltammetry and compared with their respective dissolution behaviour in blank LiCl–KCl eutectic. The anodic dissolution of U–Zr alloy in LiCl–KCl–UCl3 was also studied at 773 K to compare with the dissolution of U and Zr. The transfer coefficients evaluated by Tafel analysis and the method of Allen–Hickling for U and Zr dissolution were found to be in fair agreement with each other. U dissolution in LiCl–KCl–UCl3 and Zr dissolution LiCl–KCl–ZrCl4 were also studied by chronoamperometry and the diffusion coefficient value of U3+ was calculated to be in the range of 2.9 × 10−5 to 3.3 × 10−5 cm2 s−1 which is in agreement with those reported in literature. Convolution voltammetric analysis of Zr4+/Zr2+ redox couple in LiCl–KCl–ZrCl4 was carried out for the first time to have a comprehensive understanding of the electrode kinetics. 相似文献
80.
Chemical mechanical polishing (CMP) of copper in ammonium hydroxide based slurry in the presence of hydrogen peroxide was
investigated. The polishing trend was found to be similar to that exhibited by other slurries containing hydrogen peroxide
and various complexing agents used for Cu CMP. When the hydrogen peroxide concentration is increased, the polish rate increases,
reaches a maximum and then decreases. The location and the magnitude of the maximum depend on the ammonium hydroxide concentration.
The dissolution of copper in the NH4OH–hydrogen peroxide solution was probed by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS)
experiments. Electrical equivalent circuit (EEC) and reaction mechanism analysis (RMA) were employed to determine the mechanistic
reaction pathway of Cu dissolution in NH4OH–hydrogen peroxide system. Based on the RMA analysis, a four step catalytic mechanism with two adsorbed intermediate species
is proposed. 相似文献