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Dust particles in discharge are often levitated in a sheath region rather than in bulk plasma under gravitational conditions (on Earth). Gravity compresses dust clouds, and the gravitational force restricts the motion of the dust particles. Microgravity gives the plasmas, including dust particles, so-called complex (dusty) plasmas, where dust particles are embedded in a completely charge-neutral region of the bulk plasma. The dust cloud, as an uncompressed strongly-coupled Coulomb system, corresponds to an atomic model with physical phenomena, e.g., crystallization, phase transition, and so on. Since the phenomena are tightly connected to plasma states expressed by plasma parameters, it is significant to estimate the plasma parameters, such as electron density and temperature. The present work shows the electron density measured by the frequency shift probe in the apparatus for microgravity experiments currently boarding on the International Space Station (PK-3 plus). The frequency shift probe measurement gave electron density in the order of 108 cm-3 as a typical value in the apparatus, and demonstrated the detection of electrons in plasmas with dust particles. The spatial distribution profile of the electron density obtained in this measurement presents an aspect for the void formation of dust clouds under microgravity. [ABSTRACT FROM AUTHOR]

We developed a new Mie-scattering ellipsometry system for the analysis of the generation and transport of dusts in large plasma devices, such as nuclear fusion experiment devices. The system is a rotating-compensator type and consists of polarizer and analyzer modules and a 2-D image sensor. A preliminary experiment was carried out using a small dust plasma cubic chamber. Spherical divinylbenzene polymer particles of 2.25~\pm ~0.05~\mu \textm in diameter with a dispersion degree of 0.1 \mu \textm were injected and suspended in an argon plasma. Light intensity data for 1600 pixels on each image taken 30 times per second were summed as a function of compensator azimuth angle, and then, ellipsometric parameters $\Psi $ and $\Delta $ were determined through Fourier analysis and relational equations. By the comparison of the determined $\Psi $ and $\Delta $ values with the calculated ones based on the Mie theory, it can be stated that they agree fairly well with each other and the measurement method is reliable. [ABSTRACT FROM AUTHOR]

Abstract: Highly aligned carbon nanotubes (CNTs) were grown under high sheath electric field and gas pressure conditions by the radio frequency (RF) plasma-enhanced direct current (DC) plasma chemical vapor deposition (CVD) method due to a stabilized DC discharge. The uniform growth of highly aligned multi-walled CNTs was achieved over the entire surface area of a 50×50mm2 iron foil. The growth of multi-walled CNTs on a 75×75mm2 iron foil was also confirmed. [Copyright &y& Elsevier]

Analyzes the process of bias-enhanced nucleation of diamond through ellipsometry. Determination of the time evolution of optically equivalent thickness; Confirmation of the existence of several stages of the process; Result of accelerated elimination of weak carbon-carbon bonds.

Performs an in-process monitoring of diamond film growth with near-infrared ellipsometry. Application of microwave plasma enhanced chemical vapor deposition; Basis for the varying ellipsometric parameter trajectories; Characterization of diamond nucleation.

A simple method of alignment correction and evaluation of incidence-angle change for a laser ellipsometric monitor is presented. Once the alignment is out of order after accurate adjustment, it is corrected by an automatic aligmnent correction system. The system moves an anatyzer assembly with a X-Z translation stage so as to adjust the center of the entrance aperture to the reflected laser light from a specimen. Incidence-angle change is evaluated from the length of the movement. Performance of the system has been tested and the result was that the error was not more than 0.01° for an incidence-angle change and 0.1° for ψ and Δ. [ABSTRACT FROM AUTHOR]

A crystallike structure was successfully formed as a result of the levitation of a kind of bacillus microorganisms $Klebsiella ~pneumoniae$ in a radio frequency (RF) plasma. The crystallike structure was confirmed to be hexagonal from top-view photograph. Neutral gas friction cools the particles down to equilibrium positions. Field Emission Scanning Electron Microscope (FE-SEM) measurement suggests that RF plasma processes the surface of levitating microorganisms. [ABSTRACT FROM AUTHOR]

We found that steady-state paired-particle motion was often observed in a fine-particle cloud in the argon plasma produced by a 100-kHz high-frequency discharge. Monodispersed spherical silica particles with a diameter of $5.0~\mu \text{m}$ were trapped in the plasma. The 2-D motion of these charged particles was carefully recorded using a microscope camera, and their orbits and perturbation frequencies were analyzed. The loci and fast Fourier transform spectra of many paired particles were obtained. By moving the camera horizontally, 3-D images of the particles were recorded, and a 3-D map of the positions of charged particles was obtained. It is considered that the forces inducing the paired-particle motion were generated by the Debye shielding and the electric field surrounding the paired particles. [ABSTRACT FROM AUTHOR]

This paper reports the levitation of micro-organisms in the sheath of radio-frequency (RF) plasma. Based on simple force-balance calculations, the required electric field for the levitation of micro-organisms has been estimated. It is predicted that micro-organisms could levitate at the periphery of the sheath. Experimental results demonstrate the levitation of two species of bacillus micro-organisms Escherichia coli (E. coli) and Klebsiella pneumoniae in an RF plasma. The almost monodiverse Klebsiella pneumoniae levitating in the RF plasma formed an ordered state similar to a 2-D Coulomb crystal. Diverse E. coli particles demonstrate the tendency that the levitating height of micro-organisms decreases as the radius of particles increases. Levitating micro-organisms in plasmas can be referred as dusty plasmas. [ABSTRACT FROM AUTHOR]

The initial result of 3-D reconstruction of dusty plasma obtained through the integral photography technique has been reported. Integral photography has been applied to observe fine particles floating in a horizontally parallel-plate radio-frequency plasma. By using a simple system with a lens array and a standard charge-coupled device camera, we can identify the 3-D position of dust particles from a single exposure image obtained from one viewing port. [ABSTRACT FROM PUBLISHER]

We describe three cases of early- (cases 1–3, 28–39 years) and one of late-onset (case 4, 76 years) Alzheimer's disease (AD) with 'cotton wool' plaques (CWPs) but without a family history indicating autosomal dominant inheritance. The early-onset cases, but not the late-onset case, showed remarkable aggression, disinhibition, and impulsiveness. Spastic paraparesis was observed in only one early-onset case. Hematoxylin-eosin-stained sections showed numerous CWPs, especially in the temporal cortex, in all cases. Bielschowsky-stained sections showed neurofibrillary tangles and minor neuritic changes surrounding the CWPs in three cases, but not in case 2. Gallyas-Braak-stained sections showed weak argyrophilia in homogeneous material of the CWPs in cases 2 and 4. Quantitative analysis demonstrated that Aβ42 was deposited more predominantly than Aβ40 in three cases. However, in case 2, approximately twice as much Aβ40 as Aβ42 was deposited. Tau immunostaining demonstrated neuritic changes in three cases, but not in case 2. α-Synuclein-positive Lewy bodies (LBs) and astrocytic lesions containing non-Aβ component of AD amyloid (NAC), a central fragment of α-synuclein, were found in case 3. In conclusion, (1) a frontal lobe syndrome-like personality change may be one of the characteristic clinical features of early-onset CWP-AD, (2) the deposition pattern of Aβ40 and Aβ42 in CWP-AD is more variable than that of presenilin-1-linked cases, (3) Aβ deposition can result in development of dementia without tau pathology, and (4) CWP-AD with LBs and several other neurodegenerative disorders with LBs share a common process involving α-synuclein and NAC deposition. [ABSTRACT FROM AUTHOR]