O NE OF THE methods currently being investigated for the regenerable removal of carbon dioxide from space vehicle atmospheres involves its adsorption on synthetic zeolites. These materials, known commercially as "molecular sieves" (Linde Company) or "microtraps" (Davison Chemical Company) are crystalline alumino silicates of alkali and alkaline earth metals. Synthetic zeolites being crystalline...

The measured optical transition energies Eii of single-wall carbon nanotubes are compared with bright exciton energy calculations. The Eii differences between experiment and theory are minimized by considering a diameter-dependent dielectric constant kappa, which comprises the screening from the tube and from the environment. Different kappa dependencies are obtained for (E11(S), E22(S), E11(M)...

The aim in laparoscopic cholecystectomy is to cause minimal postoperative pain in patients by reducing the number and diameter of the trocars used, as well as to minimize the development of scar at the incision site. However, during the retraction of the gallbladder more serious problems may occur. Although several methods are suggested to securely extract the gallbladder, these methods have so...

The matter of meaning in place, is one of the main qualities of human life. People consciously or unconsciously looking for meanings in places. The importance of finding the meaning of place is that, Understanding the meaning will lead to “act” in place. Finding the place friendly, or finding it insecure will lead to act differently. Now the question is that, is the meaning of place, something ...

UNLABELLED Ultrasmall microring and microdisk lasers with an asymmetric air/GaAs/Al0.98Ga0.02As waveguide and an active region based on InAs/InGaAs/GaAs quantum dots emitting around 1.3 μm were fabricated and studied. The diameter D of the microrings and microdisks was either 2 or 1.5 μm, and the inner diameter d of the microrings varied from 20% to 70% of the outer diameter D. The microring wi...

In a previous paper (Olling 1995) a method was developed to determine the shapes of dark matter halos of spiral galaxies from an accurate determination of the rotation curve, the flaring of the gas layer and the velocity dispersion in the H I . Here I report the results for the almost edge-on Scd galaxy NGC 4244 (Olling 1996a, 1996b). The observed flaring of the H I beyond the optical disk puts...

Taking a clue from the pair of HI supershells found in the Scd galaxy NGC 3556 (M 108), we propose a new mechanism for the origin of HI supershells in gas-rich massive galaxies. In this scenario, the two supershells were inflated out of the neutral hydrogen disk due to the localised flaring of a pair of radio lobes formed by the jets ejected from the nucleus during an active phase about ∼ 107 y...

We demonstrate the feasibility of uncovering supermassive black holes in late-type, “quiescent” spiral galaxies by detecting signs of very low-level nuclear activity. We use a combination of x-ray selection and multi-wavelength follow-up. Here, we apply this technique to NGC 3184 and NGC 5457, both of type Scd, and show that strong arguments can be made that both host AGNs.

Recently, electrospinning technology has been widely used as a processing method to make nanofiber sheets (NS) for biomedical applications because of its unique features, such as ease of fabrication and high surface area. To develop a sustained dexamethasone (Dex) delivery system, in this work, poly(ε-caprolactone-co-l-lactide) (PCLA) copolymer with controllable biodegradability was synthesized...