Traditionally the dispersion of particles in polymeric materials has proven difficult and frequently results in phase separation and agglomeration. We show that thermodynamically stable dispersion of nanoparticles into a polymeric liquid is enhanced for systems where the radius of gyration of the linear polymer is greater than the radius of the nanoparticle. Dispersed nanoparticles swell the linear polymer chains, resulting in a polymer radius of gyration that grows with the nanoparticle volume fraction. It is proposed that this entropically unfavorable process is offset by an enthalpy gain due to an increase in molecular contacts at dispersed nanoparticle surfaces as compared with the surfaces of phase-separated nanoparticles. Even when the dispersed state is thermodynamically stable, it may be inaccessible unless the correct processing strategy is adopted, which is particularly important for the case of fullerene dispersion into linear polymers.

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We examine whether nonprofit organizations understate fundraising expenses in their publicly available financial statements. A large body of anecdotal evidence notes that an inexplicable number of nonprofits report zero fundraising expenses. We provide empirical evidence that the zero fundraising expense phenomenon is at least partly due to inappropriate reporting. We then examine to what extent these misreported expenses are the result of managerial incentives. Prior research finds an association between reported expenses and managerial compensation as well as the level of donations received. Using these findings we construct two incentive variables and find a positive association between misreporting behavior and managerial incentives. Our results also suggest that the use of an outside accountant reduces the probability that a nonprofit will misreport expenses, consistent with the use of an outside paid accountant increasing the reliability and usefulness of nonprofit financial reports. Finally, we find that SOP 98-2 reduced the probability that a nonprofit will misreport fundraising expenses.

The Raman effect of corundum (sapphire) was measured with an Ar+ laser source. The seven expected Raman active phonons were found and their symmetry characters determined. Assignment of the internal and external vibrations of the crystals was made and the effect of birefringence in the Raman selection rules is discussed.

A protein fraction that induces blastulation of rabbit morula and stimulates blastocyst development has been isolated from the uterus of the rabbit at early pregnancy. Partial purification of this fraction indicates that the activity is restricted to a single homogeneous protein component. The term "blastokinin" is proposed to describe the compound.

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We show it is possible to assemble nanoparticle-polymer layers in a controllable manner dictated by the difference in nano-object morphology and dielectric properties. A thin (10-100 nm) layer of the two components is spin coated onto a solid substrate and the system thermally aged to activate a cross-linking process between polymer molecules. The nanoparticles segregate to the solid substrate prior to complete cross-linking if entropic forces are dominant or to the air interface if dielectric (surface energy) forces are properly tuned. Subsequent layers are then spin coated onto the layer below, and the process is repeated to create layered structures with nanometer accuracy useful for tandem solar cells, sensors, optical coatings, etc. Unlike other self-assembly techniques the layer thicknesses are dictated by the spin coating conditions and relative concentration of the two components.