Specialty crop retention reservoir performance and design considerations to secure quality water and mitigate non-point source runoff

When blended together, homopolymers A and B will normally macrophase-separate into relatively large (≫1 μm) A-rich and B-rich phases, between which exists poor interfacial adhesion, due to a low entropy of mixing. The size scale of phase separation in such a blend can be reduced, and the extent of interfacial A-B contact and entanglement enhanced, via addition of an emulsifying agent such as an AB diblock copolymer. Diblock copolymers consist of a long sequence of A monomers covalently bonded to a long sequence of B monomers. These materials are surface-active and decrease interfacial tension between immiscible phases much in the same way as do small-molecule surfactants. Previous studies have clearly demonstrated the utility of block copolymers in compatibilizing homopolymer blends and enhancing blend properties such as fracture toughness. It is now recognized that optimization of emulsified ternary blends relies upon design considerations such as sufficient block penetration into a macrophase (to avoid block slip) and prevention of a copolymer multilayer at the A-B interface (to avoid intralayer failure).

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XRMF applications of a monolithic, polycapillary, focusing x-ray optic

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163666 ◽

1996 ◽

Vol 54 ◽

pp. 240-241

Author(s):

D. A. Carpenter ◽

Ning Gao ◽

G. J. Havrilla

Keyword(s):

Trace Elements ◽

Point Source ◽

Focal Spot ◽

Fluorescence Analysis ◽

X Rays ◽

Focal Distance ◽

Spot Diameter ◽

X Ray ◽

Focal Spot Diameter

A monolithic, polycapillary, x-ray optic was adapted to a laboratory-based x-ray microprobe to evaluate the potential of the optic for x-ray micro fluorescence analysis. The polycapillary was capable of collecting x-rays over a 6 degree angle from a point source and focusing them to a spot approximately 40 µm diameter. The high intensities expected from this capillary should be useful for determining and mapping minor to trace elements in materials. Fig. 1 shows a sketch of the capillary with important dimensions.The microprobe had previously been used with straight and with tapered monocapillaries. Alignment of the monocapillaries with the focal spot was accomplished by electromagnetically scanning the focal spot over the beveled anode. With the polycapillary it was also necessary to manually adjust the distance between the focal spot and the polycapillary.The focal distance and focal spot diameter of the polycapillary were determined from a series of edge scans.

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Theoretical And Practical Design Considerations for Ultra-High Resolution Electron Lenses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001161 ◽

1980 ◽

Vol 38 ◽

pp. 266-269

Author(s):

Y. Harada ◽

K. Tsuno ◽

Y. Arai

Keyword(s):

Optical Properties ◽

High Resolution ◽

Chromatic Aberration ◽

Point Of View ◽

Pole Piece ◽

Axial Field ◽

Design Considerations ◽

Resolution Electron ◽

Practical Design ◽

Peak Flux

Magnetic objective lenses, from the point of view of pole piece geometry, can he roughly classified into two types, viz., symmetrical and asymmetrical. In the case of the former, the optical properties have been calculated by several authors1-3) and the results would appear to suggest that, in order to reduce the spherical and chromatic aberration coefficients, Cs and Cc, it is necessary to decrease the half-width value of the axial field distribution and to increase the peak flux density. The expressions for either minimum Cs or minimum Cc were presented in the form of ‘universal’ curves by Mulvey and Wallington4).

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