No abstract available

[en] We present an investigation of NGC 2158 using Gaia DR2 data. We identified 800 most likely cluster members with membership probability higher than 90%. The mean proper motions of this object are determined as (μ _x = −0.203 ± 0.003, μ _y = −1.99 ± 0.004) mas yr⁻¹. The limiting radius, log(age), and distance of the cluster are obtained as 23.5 arcmin, 9.38 ± 0.04 Gyr, and 4.69 ± 0.22 kpc, respectively. The overall mass function slope (0.93 ± 0.14) is flatter than the Salpeter value (1.35) within the mass range of 1.17–1.44 M _⊙. This cluster also shows the mass-segregation effect and our study demonstrates that NGC 2158 is a dynamically relaxed open cluster. Using the apex diagram (AD), the apex coordinates of the cluster are obtained in different ways and are examined using the (μ _U,μ _T) diagram. The best value of the apex coordinates is determined as A = 8724 ± 160, D = −3661 ± 530. We also determined the orbit of the cluster and found that NGC 2158 moves almost in the solar antapex direction. The resulting spatial velocity of NGC 2158 is 51 km s⁻¹. A significant oscillation along the Z-coordinate up to 529 pc is detected. Various scenarios regarding the origin of this cluster are also discussed.

[en] The luminosity segregation of galaxies in clusters is studied and it is shown that the D and cD galaxies are the only morphological species that show a segregated distribution. (author)

[en] We report the formation and directed self-assembly of sub-10 nm half-pitch line patterns from lamellar microdomains of a block copolymer hybrid. The hybrid, which is a mixture of poly(styrene-b-ethylene oxide) (PS-b-PEO) and a low molecular weight organosilicate (OS), shows strong segregation between two phases (i.e. PS and PEO+OS) and forms lamellar microdomains of down to approximately 7 nm in half-pitch. Patterns applicable to multifinger device layouts are created by self-assembling the hybrid on topographic pre-patterns with a chemically non-selective surface. With careful design of the guiding topographic pattern geometry, well-controlled lateral placement including bent structures of lamellar microdomains can be obtained by this approach.

[en] Au(111) vicinal surfaces are characteristic examples of two-phase segregation or faceting. Between ∼4 deg. and 9.5 deg. miscut, the surface exhibits hill-and-valley structures formed by bunches of relatively wide (d_w∼36-41 A) and narrow (d_n∼14 A) terraces. The evolution of surface electronic states in such a faceted system is followed using a curved crystal. Beyond 4 deg. the surface state splits into distinct d_w and d_n bands. Our analysis suggests the crucial role of surface states in defining the characteristic d_w and d_n sizes during Au faceting.

[en] Particle segregation in geophysical and industrial granular flows is typically driven by gravity and shear. While gravity-induced segregation is relatively well understood, shear-induced segregation is not. In particular, what controls segregation in the absence of gravity and the interplay between shearand gravity-driven segregation remain unclear. Here, we explore the shear-induced segregation force on an intruder particle in controlled-velocity granular flows where the shear profile is systematically varied. The shear-induced segregation force is found to be proportional to the shear rate gradient, which effectively pushes the large intruder from lower to higher shear rate regions. A scaling law is developed for the segregation force that is accurate over a wide range of overburden pressures and shear rates, and hence inertial numbers.

[en] Schottky-barrier changes by the segregation and structural disorder are studied using the first-principles calculations and adopting Au/Si interface. The Schottky barrier for electrons simply decreases as increasing the valency of segregated atoms from II to VI families, which variation is shown closely related to how the Si atoms are terminated at the interface. On the other hand, the structural disorders (defects) prefer to locate near the interface and the Schottky barrier for hole carriers does not change in cases of Si vacancy and Au substitution, while it increases in cases of Si and Au interstitials reflecting the appearance of Si dangling bonds.

No abstract available

[en] The vibration-induced segregation (e.g., rising of one large intruder - so called Brazil Nut Effect (BNE)) is studied by discrete element method. Vibration frequency and amplitude are two dominating factors in the occurrence of BNE and a phase diagram is constructed. For fixed vibration amplitude, segregation only occurs when vibration frequency is within a certain range. Larger vibration amplitude can expand the range of vibration frequency for BNE. Size ratio and the intruder shape are studied under certain vibration conditions. Larger size ratio can enlarge the segregation intensity. The shape of the intruder influences the segregation process by the intruder′s orientation. Standing-like initial orientation can increase the time required for the intruder to reach the top while lying-like initial orientation cannot significantly affect the vertical segregation.

[en] Proper solid waste management has become a critical environmental issue for Metropolitan, Municipal and District Assemblies in Ghana. Despite the efforts of authorities to remediate the issue, it remains a great hurdle to overcome. This study assesses the readiness of the Ga West municipality to integrate waste segregation into solid waste management in its markets. Interviews conducted with key stakeholders and questionnaires administered to traders were analysed using a binomial logistic model. Findings from the interviews reveal that the municipality, in the period of this study, not only had no bylaws for waste segregation, but was also inadequately resourced. In addition, we found that 60% of the traders were willing to segregate waste, though only 23.4% were willing to pay for its collection. Income, work experience, and marital status were found to influence willingness to separate waste at source (P < 0.05). Age (20–30 years) and awareness were found to also have a significant influence on a trader’s willingness to pay for the collection of waste (P < 0.05). It is recommended that, for waste segregation to be implemented in markets, municipal authorities ought to formulate bylaws that promote waste segregation from source. Additionally, they must provide the required infrastructure, such as different waste skips for different types of waste; embark on massive education; and introduce innovative strategies such as paying less for the disposal of segregated waste. These measures can help to increase the willingness of market traders to pay for waste disposal.