A central problem in discrete geometry, known as Hadwiger's covering problem, asks what the smallest natural number $N\left(n\right)$ is such that every convex body ${\mathbb R}^{n}$ can be covered by a union of interiors at most its translates. Despite continuous efforts, best general upper bound for this remains it was more than sixty years ago, order ${2n \choose n}n\ln n$. In note, we imp...

Abstract Recent studies on low aromatic fuels have shown that lower soot number emissions may reduce contrail ice particle concentrations (Nice). Here we implemented, in a sophisticated radiative transfer model, two size distribution (PSD) schemes order to estimate the forcing’s (RF) dependence these prospective Nice reductions resulting from introduction of sustainable aviation fuels. The resu...

the performance of a γ-al 2 o 3 /n-decane nanofluid shell-and-tube heat exchanger in a biomass heating plant is analyzed to specify the optimum condition based on the maximum heat transfer rate and performance index for wide range of nanoparticle volume fraction (0–7%). compared with pure          n-decane, the obtained results in this research show that by using γ-al 2 o 3 /n-decane nanofluid ...

The present study investigated the effects of agitation speed, N (200, 500, 600 or 700 rpm), and dissolved oxygen concentration, C (120, >70, 70, 60, 10 or 10%), on red pigment and citrinin production by Monascus purpureus ATCC 36928, cultivated in liquid medium by a batch process. The gas flow rate was the same for all runs with C controlled by means of the incoming gas composition control (ai...

ABSTRACT-The enrichment of bedding for vermicomposting systems with organic and inorganic additives is a technique which can promote the quality of produced vermicompost. Phosphate rock and fishmeal are two available and low-cost substances which can be provided easily and inoculation of vermicompost with phosphate solubilizing microorganisms (PSMs) can enhance the availability...

We investigate the survival probability Phi(n,c) of particles performing a random walk on a two-dimensional lattice that contains static traps, which are randomly distributed with a concentration c, as a function of the number of steps n. Phi(n,c) is analyzed in terms of a scaling ansatz, which allows us to locate quantitatively the crossover between the Rosenstock approximation (valid only at ...

interactions of cationic tetrakis (n,n´,n´´,n´´´-tetramethyltetra-3,4-pyridinoporphyrazinatocobalt(ii) (co(tmtppa)) with synthetic polynucleotides, poly(a-t), poly(g-c) and calf thymus dna have been characterized in 5 mm phosphate buffer, ph 7.2, by optical absorption and fluorescence spectroscopy. the appearance of hypochromicity effect and the red shift in uv-vis spectrum of porphyrazine was ...

Kilka fish are known as the main industrial and pelagic species of Iran that are captured abundantly in the southern Caspian Sea. This study was conducted to survey the effectiveness of refinement steps on Kilka (Clupeonella delicatula) crude oil quality and fatty acid profiles. Neutralization, bleaching, winterization and deodorization were performed on crude oil with deodorization done under ...