•To accelerate the freezing various shapes of nano-powders were applied.•FEM with incorporation of implicit technique was employed.•The freezing time decline about 10.71% with growth of m.•The ...required time declines about 31.39% with raising φ.
To reduce the freezing time for a unit with curved walls which filled with water, nanoparticles has been dispersed. The shapes of CuO nano-powder can affect the conductivity of mixture and this factor efficacy has been scrutinized in current article. Freezing process is mostly affected by condition and due to negligible magnitude of velocity, only the energy equation with neglecting advection term should be considered as main equation which has been solved via FEM. The proposition of utilizing homogeneous mixture is applicable for condition of low concentration of additives and for this study, this is practical assumption. Conduction mode is significant for freezing and dispersing nanoparticle especially with greater shape factor can expedite the process. When shape factor of copper oxide nanoparticles augments with fraction of 0.04, the freezing time decline about 10.71%. The required time declines about 31.39% with raising the fraction of particles from zero to 0.04.
We consider in this paper the budgeted minimum
s
-
t
cut problem. Suppose that we are given a directed graph
G
=
(
V
,
A
)
with two distinguished nodes
s
and
t
,
k
non-negative cost functions
c
1
,
…
...,
c
k
:
A
→
Z
+
, and
k
-
1
budget bounds
b
1
,
…
,
b
k
-
1
. The goal is to find a
s
-
t
cut
C
satisfying the budget constraints
c
h
(
C
)
⩽
b
h
, for
h
=
1
,
…
,
k
-
1
, and whose cost
c
k
(
C
)
is minimum. In this paper we discuss the linear relaxation of the problem and introduce a strict partial ordering on its solutions. We give a necessary and sufficient condition for which it has an integral optimal minimal (with respect to this ordering) basic solution. We also show that recognizing whether this is the case is NP-hard.
Because of the limited range of alternative fuel vehicles (AFVs) and the sparsity of the available alternative refueling stations (AFSs), AFV drivers cooperatively deviate from their paths to refuel. ...This deviation is bounded by the drivers’ tolerance. Taking this behavior into account, the refueling station location problem with routing (RSLP-R) is defined as maximizing the AFV flow that can be accommodated in a road network by locating a given number of AFSs while respecting the range limitation of the vehicles and the deviation tolerance of the drivers. In this study, we develop a natural model for the RSLP-R based on the notion of length-bounded cuts, analyze the polyhedral properties of this model, and develop a branch-and-cut algorithm as an exact solution approach. Extensive computational experiments show that the algorithm significantly improves the solution times with respect to previously developed exact solution methods and extends the size of the instances solved to optimality. Using our methodology, we investigate the tradeoffs between covered vehicle flow and deviation tolerance of the drivers and present insights on deviation characteristics of drivers in a case study in California.
•Immobilization of H4PMo11VO40 on zirconium modified mesoporous silica SBA-15 was performed.•Catalytic behavior of sample for oxidation of dibenzothiophene was investigated.•Sample showed the high ...sulfone adsorption ability as a complementary step.
11-Molybdo-vanadophosphoric acid supported on zirconium modified mesoporous silica (SBA-15) material was synthesized and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, and N2 physical adsorption–desorption (BET) techniques. Under mild reaction conditions, the mentioned material exhibited high catalytic activity and reusability in oxidative desulfurization (ODS) reaction of model oil which was prepared by dissolving dibenzothiophene (DBT) in n-hexane. FT-IR and mass analysis showed that the main product of the DBT oxidation is its corresponding sulfone, which was adsorbed on the surfaces of zirconium-coated SBA-15. Therefore the desulfurization of the model oil was completed by filtration of the catalyst solid phase from the liquid phase. An empirical kinetic model was used to fit the rate data. The activation energy was found to be 15.92kJ/mol.
In this paper, we study the
k
edge-connected
L
-hop-constrained network design problem. Given a weighted graph
G
=
(
V
,
E
)
, a set
D
of pairs of nodes, two integers
L
≥
2
and
k
≥
2
, the problem ...consists in finding a minimum weight subgraph of
G
containing at least
k
edge-disjoint paths of length at most
L
between every pair
{
s
,
t
}
of
D
. The problem has several applications in telecommunications network design. It also has applications in reliable container transportation network design and public transportation. Even if the problem has been studied for several decades, it appears, to the best of our knowledge, that the associated polytope is not well known, even when
L
∈
{
2
,
3
}
. In this paper, we are particularly interested in the polyhedral analysis of the problem as well as an exact solving of the problem for large-scale instances. We consider the case where
L
∈
{
2
,
3
}
and present two integer programming formulations introduced in Diarrassouba et al. (2016). Then, we consider the polytope associated with these formulations, and present several new classes of valid inequalities, involving the so-called design variables. We also present separation algorithms for these inequalities and devise Branch-and-Cut algorithms for solving the problem. Finally, we present an extensive computational study for
L
∈
{
2
,
3
}
and
k
∈
{
3
,
4
,
5
}
, in which we test the efficiency of our Branch-and-Cut algorithms. We also compare the algorithm against a resolution using CPLEX Branch-and-Cut and CPLEX Benders Decomposition frameworks. The results show that our Branch-and-Cut algorithm can be competitive against these two frameworks.
A clinical isolate of Aspergillus thermomutatus (Teleomorph: Neosartorya pseudofischeri) was found to contain ~35 nm isometric virus-like particles associated with four double-stranded (ds) RNA ...segments, each of which coded for a single open reading frame. The longest dsRNA element (3589 nt) encodes a putative RNA-dependent RNA polymerase (1114 aa), the second longest dsRNA element (2772 nt) encodes a coat protein (825 aa), and the other two dsRNAs (2676 nt, 2514 nt) encode hypothetical proteins of 768 aa and 711 aa, respectively. Phylogenetic analysis of the amino acid sequences showed 41-60% similarity to the proteins coded by the dsRNAs of the most closely related virus, Penicillium janczewskii chrysovirus 2, indicating that it is a new species based on the International Committee on Taxonomy of Viruses criteria for the genus Chrysovirus. This is the first virus reported from A. thermomutatus and was tentatively named Aspergillus thermomutatus chrysovirus 1. A virus free line of the fungal isolate, cured by cycloheximide treatment, produced large numbers of conidia but no ascospores at both 20°C and 37°C, whereas the virus infected line produced ten-fold fewer conidia at 20°C and a large number of ascospores at both temperatures. The effects of the virus on fungal sporulation have interesting implications for the spread of the fungus and possible use of the virus as a biological control agent.
•The CuInS2 nanocrystals have been successfully synthesized by the new reflux route.•The effect of surfactant on the morphology was investigated.•The effect of morphology of ZnO on the photocatalytic ...activity was investigated.•The optimal pH was obtained for photocatalytic process.
In this work, CuInS2 (CIS) nanoparticles were synthesized via a simple and efficient reflux route and were composite with different nanostructures of ZnO by a thermal treatment process. The particle size of 56nm was obtained using cupper acetylacetonate (Cu(acac)2), thioacetamide (C2H5NS), indium(III) chloride tetrahydrate (InCl3·4H2O) and ethylene glycol as a solvent at the reaction time of 90min. The product was characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and ultraviolet–visible spectroscopy (UV–vis). SEM images presented the particle morphology of the CIS sample and flower-like, narcis and particle morphologies for the ZnO samples in the arranged reaction conditions. The band gap energy of 1.55eV estimated by the diffuse reflectance spectroscopy (DRS) for CIS nanoparticles, exhibited that this product can be appropriate for photocatalytic activity in the visible region of solar spectrum. Photocatalytic activity of ZnO/CIS nanocomposite was determined by photodegradation of crystal violet under visible light irradiation. Results showed that the presence of the CIS nanoparticles improves the efficiency of the photocatalytic activity of ZnO and the removal efficiency up to 100%, which prove capability of CIS nanoparticles to depredate crystal violet from aqueous solution. In this paper, the effects of morphology of ZnO nanostructures and initial pH of solution on the photocatalytic activity are investigated.
The Constrained-Routing and Spectrum Assignment (C-RSA) problem arises in the design of 5
G
telecommunication optical networks. Given an undirected, loopless, and connected graph
G
, an optical ...spectrum of available contiguous frequency slots
S
, and a set of traffic demands
K
, the C-RSA consists of assigning, to each traffic demand
k
∈
K
, a path in
G
between its origin and destination, and a subset of contiguous frequency slots in
S
subject to certain technological constraints while optimizing some linear objective function. In this paper, we devise an exact algorithm to solve the C-RSA. We first introduce an extended integer programming formulation for the problem. Then we investigate the associated polytope and introduce several classes of valid inequalities. Based on these results, we devise a Branch-and-Cut-and-Price algorithm for the problem and present an extensive computational study. This is also be compared with a Branch-and-Cut algorithm of the state-of-the-art.
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