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In group decisions, two issues need to be tackled: weighting opinions of different decision-makers and aggregating their evaluations. Many group aggregation techniques analyse these issues. These approaches can be correctly applied only if the weights assigned to all decision-makers are available. Unfortunately, there are situations where such weights are unavailable or incomplete, the negotiation required to better define them is not possible or decision-makers are unwilling to revise their judgments. These situations could pose a critical problem for the correct application of aggregation procedures. This problem is exaggerated if there are more than one group of decision-makers. In this paper, we present a new algorithm based on the Frobenius norm that considers the choice of the weights in aggregating judgments in a non-negotiable multi-group problem. This approach facilitates the computation of several sets of weights simultaneously, showing the roles played by each decision-maker and by each group in defining the global priority. To illustrate the method, we apply it in designing a new curriculum in entrepreneurship based on an entrepreneurial learning approach informed by perceptions of three stakeholders: entrepreneurship educators, entrepreneurs and entrepreneurship students. Data is collected by pairwise comparison within the analytic hierarchy process and is aggregated using our proposed approach. [ABSTRACT FROM AUTHOR]

General chemistry are key gateway courses for many Science, Technology, Engineering, and Mathematics (STEM) majors. To improve student outcomes, it is critical both to identify at-risk students and implement evidence-based instructional strategies and interventions. These remain active areas of investigation, with recent literature showing that cognitive, affective and demographic characteristics all contribute as risk factors. Here we report an assessment of demographic characteristics and early-course cognitive measures in predicting student outcomes in first-term general chemistry (GC1), comparing an adaptive learning pre-assessment using ALEKS (Assessment and LEarning in Knowledge Spaces) with a traditional diagnostic exam. Student performance was evaluated across three sections (345 students) in a quasi-experimental pre-test/post-test design using a common ACS final exam. We find that ∼57% of variance in ACS final exam scores and ∼60% of variance in final course grades is related to three predictors: initial ALEKS knowledge check, diagnostic exam score, and predicted first year QPA, an internal metric based upon high school GPA, ACT/SAT scores, and college of admission. While no single metric could identify even one-half of students scoring lowest in the course (i.e. in the bottom 15%, consistent with the percentage of D's, F's and withdrawals in our sections), in combination ∼ 80% were identified. [ABSTRACT FROM AUTHOR]

In this paper, the basic analogue of the Laplace transforms involving the product of a general class of q-polynomials along with q-analogue of Fox's H-function and q-analogue of I-function is evaluated. Limiting cases of the main outcomes are also evaluated. The paper shows a large variety of outcomes that can be achieved. [ABSTRACT FROM AUTHOR]

Highlights • The UV–vis absorption and emission spectra of a series of 1,3,6,8-tetraaryl pyrenes were obtained in solutions. • Cyclic voltammograms were recorded. • Cation radicals were generated in solution and their absorption spectra were recorded. • Single crystal X-ray structure of neutral compounds and cation radicals were studied. Graphical abstract A series of 1,3,6,8-tetraaryl pyrenes was synthesized. Photophysical and electronic properties of the neutral compounds and the optical spectra of cation radicals were studied in solution. Abstract The synthesis of 1,3,6,8-tetraaryl substituted pyrenes is described. The substituents on the aryl groups influence the optoelectronic properties of the pyrene core indicating a strong coupling between the aryl groups and the pyrene core. Electronic absroption spectra of the cation radicals generated in solution by the single electron oxidation of pyrenes reaffirmed the coupling of the aryl rings with the pyrene. The aryl groups at 1,3,6,8-positions completely inhibit the π-stacking of pyrene core in solution. Crystal structure of the cation radical salt of tetraphenyl shows charge delocalization between neutral pyrene unit and two cationic pyrene cores. Complete inhibition of the pyrene core stacking is observed in the solid state of cation radical when the dendritic pentaphenyl groups surround the pyrene core. [ABSTRACT FROM AUTHOR]

Solar fuel generation has attracted vast research interest as an environmentally benign means of producing energy from sunlight for catering to the ever growing world energy demands. As an alternative to inorganic semiconductors, organic polymers have entered the stage as promising photocatalytic systems offering a yet unprecedented scope for molecular engineering and precise tuning of optoelectronic properties. This perspective presents an overview of the development, state-of-the-art, and growth perspectives of this emerging field and highlights recent advances in photocatalyst design with a particular focus on structure-property-activity relationships in structurally well-defined 2D polymers for hydrogen evolution. [ABSTRACT FROM AUTHOR]

The optical gap of the organic semiconductor [1]benzothieno[3,2- b]benzothiophene and its 2,7-dibrominated analogue is measured in solution and in the crystalline state by means of UV-vis and emission spectroscopy. Bromination leads to a change in molecular packing from herringbone to π-stacked, resulting in a marked shift in the absorption and emission spectra which is found to be in accordance with TDDFT calculations. [ABSTRACT FROM AUTHOR]

Abstract: A simple synthesis of soluble tetrakis(poly-p-phenylene)ethylenes (TPEs), where poly-p-phenylene units contain up to 4 phenylene moieties, is accomplished using an easily available tetrakis(4-bromophenyl)ethylene and phenyl, biphenyl, and p-terphenylboronic acids, containing solubilizing iso-alkyl groups as the end-capping substituents. Electrochemical oxidation of TPEs (i.e., T1–T4) showed that they undergo reversible electrochemical oxidations and form stable cation-radical salts in solution. The evaluation of absorption and emissions characteristics of T1–T4 in solution indicated that unlike parent tetratolylethylene (T1), the higher homologues (i.e., T2–T4) show emission centered at 520nm and the quantum efficiency of emission increases with the increasing number of phenylene moieties in poly-p-phenylene units in various TPEs. [Copyright &y& Elsevier]

Soluble tetrakis(pentaphenylphenyl)ethylene (1), prepared in three steps, allows non-emissive tetraphenylethylene (TPE) to turn into an emitter (ΦF= 0.13) owing to the steric bulk of the four large hexaphenylbenzene propellers which hamper C–Ph and CC bond rotations in the TPE core. [ABSTRACT FROM AUTHOR]

The article discusses research on how the light-induced splitting of water into oxygen and hydrogen generates storable polymers and chemical fuels that could be used to address the world's energy demands. Particular attention is also given to the use of inorganic materials as semiconductor catalysts for such splits.

The electrochemical splitting of water holds promise for the storage of energy produced intermittently by renewable energy sources. The evolution of hydrogen currently relies on the use of platinum as a catalyst—which is scarce and expensive—and ongoing research is focused towards finding cheaper alternatives. In this context, 2D polymers grown as single layers on surfaces have emerged as porous materials with tunable chemical and electronic structures that can be used for improving the catalytic activity of metal surfaces. Here, we use designed organic molecules to fabricate covalent 2D architectures by an Ullmann‐type coupling reaction on Au(111). The polymer‐patterned gold electrode exhibits a hydrogen evolution reaction activity up to three times higher than that of bare gold. Through rational design of the polymer on the molecular level we engineered hydrogen evolution activity by an approach that can be easily extended to other electrocatalytic reactions. [ABSTRACT FROM AUTHOR]

The electrochemical splitting of water holds promise for the storage of energy produced intermittently by renewable energy sources. The evolution of hydrogen currently relies on the use of platinum as a catalyst—which is scarce and expensive—and ongoing research is focused towards finding cheaper alternatives. In this context, 2D polymers grown as single layers on surfaces have emerged as porous materials with tunable chemical and electronic structures that can be used for improving the catalytic activity of metal surfaces. Here, we use designed organic molecules to fabricate covalent 2D architectures by an Ullmann‐type coupling reaction on Au(111). The polymer‐patterned gold electrode exhibits a hydrogen evolution reaction activity up to three times higher than that of bare gold. Through rational design of the polymer on the molecular level we engineered hydrogen evolution activity by an approach that can be easily extended to other electrocatalytic reactions. [ABSTRACT FROM AUTHOR]

The Analytic Hierarchy Process (hereafter AHP) is a popular multi-criteria decision-making technique. The extant AHP literature usually depicts the geometric mean or the arithmetic mean as a measure of aggregation to process group decisions. However, both these measures are subject to the influence of extreme opinions, and aggregations based on them may not accurately portray the true group preference. In this paper, we propose the Common Priority Vector Procedure, which accentuates the majority group preference and diminishes the influence of extreme individual opinions. The method has been further extended to deal with multi-actor, multi-criteria and multi-group decisions. The development of Common Priority Vector Procedure, presented here, has been motivated by a real case study presented towards the end of the paper. [ABSTRACT FROM AUTHOR]