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1.
Socioecon Plann Sci ; 85: 101378, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35966449

RESUMO

With the discovery of the COVID-19 vaccine, what has always been worrying the decision-makers is related to the distribution management, the vaccination centers' location, and the inventory control of all types of vaccines. As the COVID-19 vaccine is highly demanded, planning for its fair distribution is a must. University is one of the most densely populated areas in a city, so it is critical to vaccinate university students so that the spread of this virus is curbed. As a result, in the present study, a new stochastic multi-objective, multi-period, and multi-commodity simulation-optimization model has been developed for the COVID-19 vaccine's production, distribution, location, allocation, and inventory control decisions. In this study, the proposed supply chain network includes four echelons of manufacturers, hospitals, vaccination centers, and volunteer vaccine students. Vaccine manufacturers send the vaccines to the vaccination centers and hospitals after production. The students with a history of special diseases such as heart disease, corticosteroids, blood clots, etc. are vaccinated in hospitals because of accessing more medical care, and the rest of the students are vaccinated in the vaccination centers. Then, a system dynamic structure of the prevalence of COVID -19 in universities is developed and the vaccine demand is estimated using simulation, in which the demand enters the mathematical model as a given stochastic parameter. Thus, the model pursues some goals, namely, to minimize supply chain costs, maximize student desirability for vaccination, and maximize justice in vaccine distribution. To solve the proposed model, Variable Neighborhood Search (VNS) and Whale Optimization Algorithm (WOA) algorithms are used. In terms of novelties, the most important novelties in the simulation model are considering the virtual education and exerted quarantine effect on estimating the number of the vaccines. In terms of the mathematical model, one of the remarkable contributions is paying attention to social distancing while receiving the injection and the possibility of the injection during working and non-working hours, and regarding the novelties in the solution methodology, a new heuristic method based on a meta-heuristic algorithm called Modified WOA with VNS (MVWOA) is developed. In terms of the performance metrics and the CPU time, the MOWOA is discovered with a superior performance than other given algorithms. Moreover, regarding the data, a case study related to the COVID-19 pandemic period in Tehran/Iran is provided to validate the proposed algorithm. The outcomes indicate that with the demand increase, the costs increase sharply while the vaccination desirability for students decreases with a slight slope.

2.
Appl Soft Comput ; 112: 107725, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34335121

RESUMO

As of March 24, 2020, the Food and Drug Administration (FDA) authorized to bleed the newly recovered from Coronavirus Disease 2019 (COVID-19), i.e., the ones whose lives were at risk, separate Plasma from their blood and inject it to COVID-19 patients. In many cases, as observed the plasma antibodies have cured the disease. Therefore, a four-echelon supply chain has been designed in this study to locate the blood collection centers, to find out how the collection centers are allocated to the temporary or permanent plasma-processing facilities, how the temporary facilities are allocated to the permanent ones, along with determining the allocation of the temporary and permanent facilities to hospitals. A simulation approach has been employed to investigate the structure of COVID-19 outbreak and to simulate the quantity of plasma demand. The proposed bi-objective model has been solved in small and medium scales using ε -constraint method, Strength Pareto Evolutionary Algorithm II (SPEA-II), Non-dominated Sorting Genetic Algorithm II (NSGA-II), Multi-Objective Grey Wolf Optimizer (MOGWO) and Multi Objective Invasive Weed Optimization algorithm (MOIWO) approaches. One of the novelties of this research is to study the system dynamic structure of COVID-19's prevalence so that to estimate the required plasma level by simulation. Besides, this paper has focused on blood substitutability which is becoming increasingly important for timely access to blood. Due to shorter computational time and higher solution quality, MOIWO is selected to solve the proposed model for a large-scale case study in Iran. The achieved results indicated that as the plasma demand increases, the amount of total system costs and flow time rise, too. The proposed simulation model has also been able to calculate the required plasma demand with 95% confidence interval.

3.
J Org Chem ; 83(23): 14743-14750, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30398359

RESUMO

This report explains an efficient method for synthesis of an array of quinolines via the reaction of 2-aminoaryl ketones with terminal and internal alkynes in the presence of propylphosphonium tetrachloroindate ionic liquid supported on nanosilica (PPInCl-nSiO2) as a heterogeneous and reusable catalyst under solvent-free conditions. Inspired by this catalytic system, the first easy one-step synthesis of symmetric and unsymmetric pyrido[3,2- g or 2,3- g]quinolines was investigated through the reaction of diaroylphenylenediamines with one alkyne or two different alkynes.

4.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 1): o16, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24526967

RESUMO

In the title compound, C24H19N, the di-methyl-amino group is inclined to the benzene ring by 2.81 (9)°. Their mean plane makes a dihedral angle of 64.12 (2)° with the mean plane of the pyrene ring system [r.m.s. deviation = 0.031 (1) Å]. In the crystal, mol-ecules are linked via C-H⋯π inter-actions, which connect neighbouring mol-ecules into columns along the c axis.

5.
Chemosphere ; 364: 142961, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39084300

RESUMO

Waste disposal systems are crucial components of environmental management, and focusing on this sector can contribute to the development of various other sectors and improve social welfare. Urban waste is no longer solely an environmental issue; it now plays a significant role in the economy, energy, and value creation, with waste disposal centers (WDCs) being a key manifestation. The purpose of this study is to measure the performance of WDCs in the state of Nuevo León, Mexico, with the aim of developing environmental, social, and governance (ESG) strategies to strengthen and prepare the WDCs for the industrial developments in this state. By identifying environmental variables and undesirable factors, the efficiency and managerial capacity of 32 WDCs were assessed. The analysis revealed that 9 out of the 32 WDCs are technically efficient, while the remaining 23 require significant improvements. Using the Data Envelopment Analysis (DEA) technique, an average efficiency score of 0.91 was found, with a standard deviation of 0.08. The managerial capacity analysis indicated that the highest-ranked WDC achieved an efficiency score of 1, whereas the lowest-ranked WDC scored 0.67. Finally, an operational map of development strategies was developed using the Interpretive Structural Modeling (ISM) and Matrix Impact Cross-Reference Multiplication Applied to a Classification (MICMAC) approach. The results indicate that four phases of development should be followed for real development and maturity of development in these WDCs, including Groundwork, Structuring, Development and Growth, and Smart Maturity.

6.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): m322, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23794986

RESUMO

In the title compound, [Ni(C8H14N6S2)], the Ni(II) ion is coordinated by N2S2 donor atoms of the tetradentate thio-semicarbazone ligand, and has a slightly distorted square-planar geometry. In the crystal, inversion-related mol-ecules are linked via pairs of N-H⋯N and N-H⋯S hydrogen bonds, forming R 2 (2)(8) ring motifs. Mol-ecules are further linked by slightly weaker N-H⋯N, N-H⋯S and C-H⋯S hydrogen bonds, forming two-dimensional networks which lie parallel to the bc plane.

7.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 1): m46, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23476342

RESUMO

The asymmetric unit of the title compound, [Fe(C11H19Si)2], consists of one half of a ferrocene derivative. The Fe(II) atom lies on a twofold rotation axis, giving an eclipsed conformation for the cyclo-penta-dienyl ligands. No significant inter-molecular inter-actions are observed in the crystal structure.

8.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 4): o541, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23634080

RESUMO

In the title compound, C21H24BrNO4, the dihedral angle between the heterocyclic ring and the pendant aromatic ring is 80.20 (13)°. The hexahydroquinone [i.e. the one with the C=O group] ring adopts a sofa conformation. An intra-molecular O-H⋯O hydrogen bond generates an S(6) ring motif. The ethyl group is disordered over two sets of sites with a refined site occupancy ratio of 0.633 (10):0.366 (10). In the crystal, mol-ecules are linked by N-H⋯O inter-actions, forming chains parallel to [101]. There are no significant C-H⋯π or π-π inter-actions in the crystal structure.

9.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 4): m392, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22589779

RESUMO

In the title compound, [Cu(C(19)H(16)Br(4)N(2)O(2))], the Cu(II) ion and the substituted C atom of the diamine fragment lie on a crystallographic twofold rotation axis. The geometry around the Cu(II) ion is distorted square-planar, which is defined by the N(2)O(2) donor atoms of the coordinated Schiff base ligand. The dihedral angle between the symmetry-related substituted benzene rings is 25.33 (14)°. The crystal structure is stabilized by an inter-molecular π-π inter-action [centroid-centroid distance = 3.8891 (18) Å].

10.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 4): o1035, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22589906

RESUMO

In the title compound, C(16)H(15)NO(4), a potential bidentate N,O-donor Schiff base ligand, the benzene rings are inclined to one another by 4.24 (12)°. The mol-ecule has an E conformation about the C=N bond. An intra-molecular O-H⋯N hydrogen bond makes an S(6) ring motif. In the crystal, pairs of O-H⋯O hydrogen bonds link the mol-ecules, forming inversion dimers with R(2) (2)(8) ring motifs. These dimers are further connected by C-H⋯O inter-actions, forming a sheet in (104). There is also a C-H⋯π inter-action present involving neighbouring mol-ecules.

11.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 4): o1036, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22589907

RESUMO

In the title compound, C(18)H(20)N(2)O(3), a potential bidentate N,O-donor Schiff base ligand, the benzene rings are inclined at an angle of 12.25 (19)°. The mol-ecule has an E conformation about the C=N bond. One of the ethyl groups is disordered over two positions, with a refined site-occupancy ratio of 0.55 (1):0.45 (1). An intra-molecular O-H⋯N hydrogen bond makes an S(6) ring motif. In the crystal, pairs of O-H⋯O hydrogen bonds link mol-ecules, forming inversion dimers with R(2) (2)(8) ring motifs.

12.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): m752, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22719312

RESUMO

In the title compound, [Cu(C(19)H(16)I(4)N(2)O(2))], the Cu(II) atom and the substituted C atom of the diamine segment lie on a crystallographic twofold rotation axis. The geometry around the Cu(II) atom is distorted square-planar, which is supported by the N(2)O(2) donor atoms of the coordinated Schiff base. The dihedral angle between the symmetry-related substituted benzene rings is 29.40 (19)°. In the crystal, a short I⋯I [3.8766 (6) Å] contact is present and links neighbouring mol-ecules into chains propagating along the a axis.

13.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): m753, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22719313

RESUMO

The asymmetric unit of the title compound, [Ni(C(19)H(16)Br(4)N(2)O(2))], comprises half of a Schiff base complex. The geometry around the Ni(II) atom, located on a twofold rotation axis, is distorted square-planar, which is supported by the N(2)O(2) donor atoms of the coordinated ligand. The dihedral angle between the substituted benzene rings is 23.19 (17)°. In the crystal, a short inter-molecular Br⋯Br [3.6475 (7) Å] inter-action is present.

14.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 2): m182, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22346855

RESUMO

In the title Schiff base complex, [Cu(C(19)H(16)Cl(4)N(2)O(2))], the geometry around the Cu(II) atom is distorted square-planar defined by the N(2)O(2) donor atoms of the coordinated ligand. The dihedral angle between the substituted benzene rings is 29.95 (16)°. In the crystal, mol-ecules are linked along the b axis, forming individual dimers through C-H⋯O inter-actions. The crystal structure is further stabilized by inter-molecular π-π inter-actions [centroid-centroid distance = 3.6131 (17) Å].

15.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 2): m193, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22346862

RESUMO

In the title compound, [Ni(C(19)H(16)Cl(4)N(2)O(2))], the Ni(II) ion is in a distorted square-planar environment coordinated by two N atoms and two O atoms of the tetra-dentate ligand. The dihedral angle between the benzene rings is 24.8 (2)°. In the crystal, mol-ecules are linked into chains along the b axis by weak C-H⋯O and C-H⋯Cl inter-actions. An inter-molecular Cl⋯Cl [3.4564 (19) Å] inter-action is present which is shorter than the sum of the van der Waals radii of Cl atoms (3.50 Å).

16.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 2): o292, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22346930

RESUMO

The asymmetric unit of the title compound, C(30)H(28)N(2)O(2), comprises half of a potential tetra-dentate Schiff base ligand; an inversion centre is situtated at the center of the butane-diamine spacer. The central methyl-ene segment of the diamine spacer is disordered over two positions with a refined site-occupancy ratio of 0.651 (7):0.349 (7). The phenyl ring and the hy-droxy-substituted benzene ring are almost perpendicular to each other, with a dihedral angle of 87.90 (8) Å. Intra-molecular O-H⋯N hydrogen bonds make S(6) ring motifs.

17.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 2): o323, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22346957

RESUMO

In the title mol-ecule, C(19)H(18)Br(4)N(2)O(2), the dihedral angle between the benzene rings is 73.9 (2)°. Two intra-molecular N-H⋯O hydrogen bonds make S(6) ring motifs. In the crystal, mol-ecules are linked via C-H⋯O inter-actions, forming chains propagating along the a-axis directon. A short C⋯Br [3.401 (5) Å] contact is present in the crystal structure, which is further stabilized by a π-π inter-action [centroid-centroid distance = 3.739 (3) Å].

18.
Artigo em Inglês | MEDLINE | ID: mdl-22259376

RESUMO

In the title compound, [Ni(C(21)H(24)N(2)O(2))]·H(2)O, both the complex mol-ecule and the water mol-ecule lie on a twofold rotation axis. The Ni(II) ion is coordinated in a distorted square-planar geometry by the tetra-dentate ligand. The dihedral angle between the two symmetry-related benzene rings is 47.12 (8)°. In the crystal, pairs of symmetry-related O-H⋯O hydrogen bonds form R(2) (2)(6) ring motifs. In addition, there are weak inter-molecular C-H⋯O hydrogen bonds, and π-π stacking inter-actions with a centroid-centroid distance of 3.4760 (8) Å.

19.
Artigo em Inglês | MEDLINE | ID: mdl-22259428

RESUMO

In the title compound, C(19)H(18)Cl(4)N(2)O(2), a potential tetra-dentate Schiff base ligand, the dihedral angle between the two benzene rings is 48.01 (10)°. The configuration about the two C=N bonds is E and two intra-molecular O-H⋯N hydrogen bonds make S(6) ring motifs. In the crystal, mol-ecules are linked along the b axis via inter-molecular C-H⋯Cl inter-actions. The crystal structure is further stabilized by an inter-molecular π-π inter-action [centroid-centroid distance = 3.5744 (12) Å].

20.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 3): o564, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22412483

RESUMO

The asymmetric unit of the title compound, C(19)H(18)I(4)N(2)O(2), comprises a potentially tetra-dentate Schiff base ligand. The disordered H atoms on the N and O atoms were refined with site occupancies of 0.54 (8)/0.46 (8) and 0.59 (7)/0.41 (7), respectively. The dihedral angle between the benzene rings is 73.3 (3)°. Intra-molecular O-H⋯N and N-H⋯O hydrogen bonds make S(6) ring motifs. Short I⋯I [3.8919 (7) Å] and I⋯Cg [Cg is a ring centroid; 3.911 (2) Å] contacts are present in the crystal structure. The crystal structure is further stabilized by inter-molecular π-π inter-actions [centroid-to-centroid distance = 3.827 (3) Å].

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