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The compatibility of chitosan with divalent salts over monovalent salts for the preparation of solid polymer electrolytes
No full textIn this study the compatibility of chitosan (CS) with divalent inorganic salt is discussed. Solid polymer electrolytes (SPEs) consist of CS as a host polymer and magnesium triflate (MgTf) as a dopant divalent salt have been prepared by solution cast technique. The room temperature DC ionic conductivity of CS-based SPE containing 50 wt% of MgTf is determined to be around ≈10−4 S/cm. The surface morphology of the films are then examined using a field emission scanning electron microscopy (FE-SEM). The crystalline phase of pure CS is found to reduce upon the addition of MgTf salt. The compatibility of CS with divalent salts are discussed at high salt concentration on the bases of the surface morphology and X-ray diffraction (XRD) results. The smooth surface micrographs and broad peaks of XRD spectra are interpreted in reference to lattice energy and cationic size of salt. The smooth surface and low resistance (Rb = 47.8 Ohm) at high salt content (50 wt%) are clear signs that CS is more compatible with divalent salts than with other monovalent salts. At low temperature range, the DC conductivity versus 1000/T is shown to follow the Arrhenius equation. The dispersion region of AC conductivity spectra has been used to calculate the frequency exponent, s. Based on the value of s as a function of temperature, different ion transport models have been discussed to interpret the pattern of DC ionic conductivity versus 1000/T. The appearance of peaks in M″ spectra and their absence in ɛ″ spectra reveals that the relaxation process is a non-Debye type
Impact of corporate governance on related party transactions in family-owned firms in Pakistan
No full textThis is an empirical study to examine the impact of corporate governance (CG) variables, namely independent directors index (IDI), family directorship (FD), and family ownership (FO), on the types of related party transactions (RPTs) that prevail in family-owned firms in developing countries. The focus of this study is on Pakistan whereby it was found major shareholders of Pakistani family-owned firms expropriate resources through RPTs. This study analysed panel data of 108 firms of family-owned firms listed on the Karachi stock exchange from 2004 to 2014 after the introduction of CG codes in 2002. The study contributes to literature by categorising all RPTs into three types - RPTb, RPTe, and RPTo. It also develops an index of independence directors comprising three dimensions, namely board composition, financial expertise, and tenure of the independent non-executive director. Different panel least squares models for different RPTs have been employed to examine the relationship between RPTs and CG variables. This study found that 90% of family-owned firms in Pakistan scored low for independent director’s index. Hence, CG is weaker in Pakistani family-owned firms where major shareholders expropriate resources through RPTb and RPTe. Further, CG variables, namely IDI and FD are negatively related to RPTs and the concentration of family ownership of firms has a negative relationship with RPTs, and this has a negative tendency for the resource expropriation of family-owned firms. The study concludes the negative relationship of corporate governance and concentration of major shareholder exploit the interest of minority shareholders in Pakistani family-owned firms
Health-seeking behaviour and delayed presentation of oral cancer patients in a developing country: A qualitative study based on the self-regulatory model
No full textBackground: The aim of this study was to explore reasons for delayed health-seeking for late stage oral cancer patients. Methods: Semi-structured in-depth interviews were conducted with 35 oral cancer patients with TNM stage III to IV disease, who were treated at six tertiary regional centres managing oral cancer throughout Malaysia. Interviews were audio-recorded, transcribed verbatim, coded using NVivo (version 10.0) qualitative software and analysed using framework analysis. Results: Participants interpreted their early symptoms as a minor condition and did not consider it as requiring immediate attention. Four types of coping strategies causing delayed help-seeking emerged: 1) self-remedy 2) self-medication 3) seeking traditional healers and 4) consulting general medical practitioners (GPs) instead of dentists. Socio-economic factors, cultural beliefs and religious practices have some influence on diagnostic delay. Conclusion: Low levels of public knowledge and awareness regarding early signs and symptoms of oral cancer as well as GPs' misdiagnosis of early lesions results in delayed diagnosis
Nitrogen-doped graphene-supported zinc sulfide nanorods as efficient Pt-free for visible-light photocatalytic hydrogen production
No full textNitrogen-doped graphene-ZnS composite (NG-ZnS) was synthesized by thermal treatment of graphene-ZnS composite (G-ZnS) in NH3 medium. In the second step, the as-synthesized samples were deposited on indium tin oxide glass (ITO) by electrophoretic deposition for photocatalytic hydrogen evolution reaction. The as-prepared NG-ZnS-modified ITO electrode displayed excellent photocatalytic activity, rapid transient photocurrent response, superior stability and high recyclability compared to the pure ZnS and G-ZnS-modified ITO electrode due to the synergy between the photocatalytic activity of ZnS nanorods and the large surface area and high conductivity of N-graphene
Intellectual capital and performance measurement systems in Iran
No full textPurpose: The purpose of this paper is to empirically explore how the effect of intellectual capital (IC) on organizational performance is indirect and mediated through performance measurement (PM) systems. Design/methodology/approach: Data were collected from a survey of 128 chief financial officers of Iranian publicly listed companies. Hypotheses were tested using partial least squares regression, a structural modeling technique which is appropriate for highly complex predictive models. Findings: Results from the structural model indicate that, in general, companies with a higher level of IC place a premium on the balanced use of PM systems in a diagnostic and interactive style. Furthermore, the results provide some evidence that IC is indirectly associated with organizational performance through the intervening variable of the balanced use of interactive and diagnostic PM systems. Practical implications: This study sheds light on the issue of how senior management should use PM systems to take full advantage of intellectual assets which could lead to improved organizational performance. Originality/value: This is the first study of its kind to synthesize a model which examines IC, PM systems, and organizational performance. Although the effect of different types of intangible assets on performance has been substantially examined in the literature, less effort has been devoted to understanding the role of PM systems in leveraging an organization’s IC
The impact of exchange rate regimes on economic growth: Empirical study of a set of developing countries during the period 1974–2006
No full textAn increment in the quantity of services/goods manufactured per-head of the population over time denotes economic growth of a country. Exchange Rate Intermediate Regimes are unable to continue under conditions of capital movement. To examine the relationship between exchange rate regimes and economic growth. This study has kept its focus on the economic growth of a set of developing countries during the years (1974–2006). Fixed effects and pooled regression for 16 developing countries have been incorporated as the methodologies techniques for data. Analysis of data was performed through SPSS. A relationship between exchange rate regimes and economic growth has been identified through statistical approaches. The results indicated that as compared to flexible exchange regime, growth rate was higher by 1.2% when fixed exchange regime was adopted; and a growth rate of 0.64% was achieved under the intermediate regime when compared with the flexible regime. A positive impact has been identified in exchange rate regimes upon economic growth of the developing countries. Countries following the flexible exchange rates are facing scarcity for the existence of advanced financial systems, which deprives them of enjoying the benefits of flexible regime
Subjective well-being in China, 2005–2010: The role of relative income, gender, and location
No full textWe use data from two rounds of the Chinese General Social Survey (CGSS) to study the determinants of subjective well-being in China over the period 2005–2010 during which self-reported happiness scores show an increase across all income groups. Ordered probit regression analysis of well-being reveals large influence of gender, rural residency, and household income. After controlling for demographic attributes, health status, unemployment status, number of children, agricultural hukou (household registration identity) and educational attainment, household assets, the influence of past and future income, and province dummies, we find that women, urban residents, and people with higher income are happier in China. More schooling, better health, and being employed are positively and significantly correlated with well-being. Sub-sample analysis reveals that the rich only care about relative income whereas the effect of absolute income dominates in case of the poorer section. The influence of absolute income is larger among women compared to men and in turn explains why women, despite being poorer, are happier in China, conditional on socioeconomic differences. On the other hand, rural residents are poorer than urban residents so that conditional on having the same income, there is no rural–urban happiness gap. Our results suggest that while further decline in poverty will enhance well-being in China, policies that reduce rural–urban and gender inequalities are also likely to boost well-being
A novel association rule mining approach using TID intermediate itemset
No full textDesigning an efficient association rule mining (ARM) algorithm for multilevel knowledge-based transactional databases that is appropriate for real-world deployments is of paramount concern. However, dynamic decision making that needs to modify the threshold either to minimize or maximize the output knowledge certainly necessitates the extant state-of-the-art algorithms to rescan the entire database. Subsequently, the process incurs heavy computation cost and is not feasible for real-time applications. The paper addresses efficiently the problem of threshold dynamic updation for a given purpose. The paper contributes by presenting a novel ARM approach that creates an intermediate itemset and applies a threshold to extract categorical frequent itemsets with diverse threshold values. Thus, improving the overall efficiency as we no longer needs to scan the whole database. After the entire itemset is built, we are able to obtain real support without the need of rebuilding the itemset (e.g. Itemset list is intersected to obtain the actual support). Moreover, the algorithm supports to extract many frequent itemsets according to a pre-determined minimum support with an independent purpose. Additionally, the experimental results of our proposed approach demonstrate the capability to be deployed in any mining system in a fully parallel mode; consequently, increasing the efficiency of the real-time association rules discovery process. The proposed approach outperforms the extant state-of-the-art and shows promising results that reduce computation cost, increase accuracy, and produce all possible itemsets
Highly efficient green mesostructured urea functionalized on SBA-15 catalysts for selective synthesis of benzlidenemalononitrile
No full textA series of urea-immobilized SBA-15 catalysts were synthesized via post grafting method using 3-chloropropyltriethoxysilane (CPTES) as the anchoring agent. The solid catalyst was characterized by PXRD, N2 adsorption-desorption, FT-IR, elemental analyzer, TEM, CO2-TPD and 29Si CP/MAS NMR. Detailed analysis of the pore size illustrated the mesoporous nature of the immobilized catalyst. The as-prepared catalyst was further evaluated in the Knoevenagel condensation reaction under different reaction conditions. Benzaldehyde was employed in the Knoevenagel condensation reaction with malononitrile. Catalytic results showed that the Urea(4.8)/SBA-15 exhibits high efficacy (98% of yield) for promoting this reaction at 40 °C and in the absence of a solvent. Under the same reaction conditions, acetylacetone led to a lower benzaldehyde conversion of 10%, whereas ethyl cyanoacetate provides up to 88% conversion. The catalyst could be recycled and reused for at least five reaction cycles with slight loss of catalytic activity
Transformerless high gain boost and buck-boost DC-DC converters based on extendable switched capacitor (SC) cell for stand-alone photovoltaic system
No full textThis paper presents transformerless high gain boost and buck-boost DC-DC converters (B-BBCs) with extendable switched capacitor cells (SCs), suitable for applications operating at high voltage, above 300 V. Boosting low voltage to a high-enough level, with low duty ratio, is beyond the practical capability of the conventional boost converter. In addition, high duty ratio needed for operation of the boost converter, results in higher component stress that suppresses the overall efficiency of the converter. Therefore, by a convenient integration of SCs with conventional B-BBCs, increased voltage gain is attained with fewer losses. Such converters can be employed for Photovoltaic (PV) systems. The operational principles and modes of operation are analyzed to justify the utility of converters for stand-alone PV systems. Moreover, the proposed modular structure allows to increase SC cells in order to obtain reduced voltage stress on switching components with a higher voltage gain. Simulation and experimental results based on 100 W laboratory prototype extol the theoretical analysis