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The combined use of anticorrosive and load carrying additives in industrial and automotive lubricants has been well known for many years. In some cases, the same additive has been claimed to act both for load carrying and anticorrosive properties. The synergistic and antagonistic effects of various chemicals involved in lubricant system employing both these two types of additives are the subjects of present interest.

The purpose of this paper is to study the effect of palm olein, amine phosphate and 4‐nonyl phenoxy acetic acid (NPAA) added to a commercial lubricant in terms of tribological properties such as wear and coefficient of friction.

A tribological study on the lubrication performance of a lubricant‐based palm oil (PO) containing anti‐wear and antioxidant combined corrosion inhibitor additive was carried out using a universal sliding wear machine. In this experiment, amine phosphate and NPAA were selected as additive to be mixed with PO (palm olein) in several concentrations and commercial lubricant 20W‐50 for the tests. Various PO blended samples with additional 1 and 3 percent additive were used in this study. The experiments were performed under 252 rpm sliding speed for 2 h where the oil temperature reached 100°C.

The analysis showed that the average wear coefficient and the mean wear scar diameter (MWSD) which is normalized to the 1.4 KPa water pressure generates lower values for the PO containing additives than 100 percent PO, commercial lubricant and their blended. The coefficients of friction and wear were also lower for the samples with additives compared to other. To consolidate the result, viscosity of used samples is checked and shows the additives improved the viscosity stability. Finally, the overall study concluded that PO‐added additives have the potential to be one of the ingredients in effective lubricant oil.

The paper is limited to findings based on a Universal Sliding Machine Test under certain conditions. The test has been conducted on the basis of three types of chemical compounds (palm olein, amine phosphate and NPAA) which are designed as a combination of anti‐wear and antioxidant additive. Wear and friction characteristics of the lubricant with and without these additives are analyzed in this paper. However, the film formation and microstructure analysis of the lubricated materials are excluded in this study.

This paper shows a significant reduction of average wear rate and friction coefficient when palm olein and additive added to the lubricant compared to pure commercial lubricant. In terms of wear scar diameter (WSD), with additional palm olein and additive produces lower WSD which is under the standard limit of diesel lubricity. These results have confirmed that by using palm olein as renewable component together with amine phosphate and NPAA additive would improve lubrication performance as well as improves biodegradability of the lubricant.

This paper emphasises the advantages of synthetic additives that are derived from renewable resources. Since environmental issues are now stringent, many lubricant industries have focused on environmentally friendly lubricant and researches on this particular area become important. The presented tests have been carried out in the above area which is close to those applied in lubricant industry. Thus, the results are reliable and could be very useful both for lubricant designers and the researchers of lubricant and additive formulation.

Using a unique dataset of a commercial microfinance institution (MFI) in Madagascar, the purpose of this paper is to investigate how credit access probabilities and loan volume rationing magnitudes for farmers change if the MFI switches to offer flexible microfinance loans, which can account for agricultural production specifics.

The authors estimate probit models for the probability of receiving a loan and Heckman models to investigate the magnitude of volume rationing for all micro loan applications and disbursements of the MFI, differentiating between farmers with standard microfinance loans and farmers with flexible microfinance loans.

The results reveal that agricultural firms with flexible microfinance loans have significantly higher credit access probabilities than non‐agricultural firms and agricultural firms with standard microfinance loans. Furthermore, it was found that agricultural firms with flexible microfinance loans are stronger volume rationed than non‐agricultural firms and agricultural firms with standard microfinance loans.

Even if the authors can show that access to credit for agricultural firms in Madagascar can be enhanced by the provisioning of flexible microfinance loans, the investigated MFI only introduced flexible microfinance loans in 2011 and currently only offers them through five branch offices. Thus, the product is new to the MFI, and results might change with increasing outreach to other geographic regions in Madagascar. Furthermore, the conditions for agricultural production in Madagascar are unique, and the results might change in different country contexts.

The paper's findings suggest that flexible microfinance loans can contribute to the financial inclusion of farmers with seasonal production types. They also suggest that standard microfinance loans seem to be adequate for farmers with less seasonal production types, e.g. animal husbandry.

To the best of the authors' knowledge, this is the first paper to investigate the effects of flexible microfinance loan provision for credit access of small agricultural firms in developing countries in general, and in Madagascar in particular.

The purpose of this paper is to address various works on mixed convection and proposes 10 unified models (Models 1–10) based on various thermal and kinematic conditions of the boundary walls, thermal conditions and/ or kinematics of objects embedded in the cavities and kinematics of external flow field through the ventilation ports. Experimental works on mixed convection have also been addressed.

This review is based on 10 unified models on mixed convection within cavities. Models 1–5 involve mixed convection based on the movement of single or double walls subjected to various temperature boundary conditions. Model 6 elucidates mixed convection due to the movement of single or double walls of cavities containing discrete heaters at the stationary wall(s). Model 7A focuses mixed convection based on the movement of wall(s) for cavities containing stationary solid obstacles (hot or cold or adiabatic) whereas Model 7B elucidates mixed convection based on the rotation of solid cylinders (hot or conductive or adiabatic) within the cavities enclosed by stationary or moving wall(s). Model 8 is based on mixed convection due to the flow of air through ventilation ports of cavities (with or without adiabatic baffles) subjected to hot and adiabatic walls. Models 9 and 10 elucidate mixed convection due to flow of air through ventilation ports of cavities involving discrete heaters and/or solid obstacles (conductive or hot) at various locations within cavities.

Mixed convection plays an important role for various processes based on convection pattern and heat transfer rate. An important dimensionless number, Richardson number (Ri) identifies various convection regimes (forced, mixed and natural convection). Generalized models also depict the role of “aiding” and “opposing” flow and combination of both on mixed convection processes. Aiding flow (interaction of buoyancy and inertial forces in the same direction) may result in the augmentation of the heat transfer rate whereas opposing flow (interaction of buoyancy and inertial forces in the opposite directions) may result in decrease of the heat transfer rate. Works involving fluid media, porous media and nanofluids (with magnetohydrodynamics) have been highlighted. Various numerical and experimental works on mixed convection have been elucidated. Flow and thermal maps associated with the heat transfer rate for a few representative cases of unified models [Models 1–10] have been elucidated involving specific dimensionless numbers.

This review paper will provide guidelines for optimal design/operation involving mixed convection processing applications.

The purpose of this paper is to establish the relationship between managerial competence, managerial risk-taking behaviour and financial service outreach of microfinance institutions (MFIs).

In this cross-sectional and correlational study, the authors surveyed 52 branches of MFIs from a population of 60 branches of 20 MFIs in eastern Uganda. Two respondents, a branch manager and a senior loan officer, were the units of enquiry for each branch. The authors put forward and tested four hypotheses relating to the significance of the relationship between perceived managerial competence, risk-taking behaviour and financial service outreach using SPSS version 20. The authors established the hypothesized relationships using Pearson correlation coefficients and obtain a mediating effect of risk-taking behaviour using partial corrections and regression analysis.

The results suggest positive and significant relationships between perceived managerial competence, risk-taking behaviour and financial service outreach. However, while the direct relationship between managerial competence and financial service outreach without the mediation effect of risk-taking behaviour of managers was found to be significant, its magnitude reduces when mediation of risk-taking behaviour is allowed. Thus the entire effect does not only go through managerial competence but majorly also, through risk-taking behaviour of managers.

This study did not control for environmental factors such as laws and regulations. As such the model may have been under fitted. Nevertheless, the study has introduced a clearer understanding that outreach performance in MFIs rests with competent managers in strategic positions operating in synergy with their risk-taking behaviour. The study informs policy makers that outreach performance of the MFIs depends on the quality of the competence managers have in addition to their risk-taking propensities.

Efforts by the stakeholders to improve financial service outreach must be matched with appropriate competences and risk-taking behaviour of managers.

The results contribute to extant literature by investigating two explanatory variables for financial service outreach and provide initial evidence of the mediating effect of intrinsic high risk-taking behaviour of managers. Results add to the conceptual improvement in risk-taking behaviour and lend considerable support for the behavioural perspective in the study of financial service outreach of MFIs.

The purpose of this paper is to investigate the relationship between commercial bank lending terms, financial literacy and access to formal credit by small and medium enterprises (SMEs).

In this cross-sectional study, the authors surveyed 384 business owners or managers of SMEs in Uganda. The authors applied confirmatory factor analysis to reduce the number of factors and identify the important elements that capture commercial lending terms, financial literacy and access to formal credit. The authors put forward and tested two hypotheses relating to the significance of the relationship between perceived commercial bank lending terms, financial literacy and access to formal credit using structural equation modelling with analysis of moment structures 18.

The results suggest a positive and significant relationship between perceived commercial bank lending terms, financial literacy and access to formal credit. Moreover, the ANOVA results serendipitously show that access to formal credit varies with type of business and turnover. However, collateral and loan repayment periods are not observed variables for commercial bank lending terms. The most significant observed variable for commercial bank lending terms is interest rates. This, together with financial literacy, explains 31 per cent of the variances in access to formal credit by SMEs in Uganda.

The study is limited to the SME firms registered and operating in Kampala, Uganda and it is possible that the results are only applicable to these firms in Uganda. Nevertheless, the findings have implications to commercial banks wishing to improve the turnover of their micro-lending schemes.

Efforts by the stakeholders to improve financial literacy of SMEs owners and managers must be matched with favourable interest rates if access to formal credit is to be enhanced.

The findings also have implications for governments aiming at improving access to finance to overcome income inequality problems, and also improve their growth.

The results provide initial evidence of the aggregate explanatory power of interest rates and financial literacy for the criterion variable, access to formal credit by SMEs.

The purpose of this paper is to measure the financial inclusion dimensions from the perspective of beneficiaries (demand-side).This research additionally attempts to assess the impact of financial inclusion on socio-economic status of primitive tribal groups (PTGs) in India.

Using an exploratory factor analysis, the financial inclusion dimensions are identified for a sample of 520 families belonging to PTGs in India. In the next step, reliability and validity test were used to establish the financial inclusion dimensions and socio-economic status factors through confirmatory factor analysis using analysis of moment structures. Finally, structural equation modeling (SEM) had been applied for testing the hypothetical relationships.

The study documented five-dimensions of measuring financial inclusion from demand side perspective. The dimensions are as follows: physical proximity, availability, ease of access, affordability and usage. It was found that these factors represent the various dimensions of financial inclusion, which has a significant impact on socio-economic status of the beneficiaries.

The research results focus on dimensions of financial inclusion, which have an impact on the socio-economic status among the most PTGs in India. The research offers ideas to policymakers to outline strategies to enhance the access to and usage of financial services.

The present research is one of the first few studies that present the demand-side perspective to assess the financial inclusion dimensions of the “financially most excluded” groups – PTGs in India using a SEM approach.

The purpose of this study is to introduce working capital efficiency multiplier (WCEM) as a direct profitability measure of working capital management. The existing accounting measures in the literature establish an indirect approach to study the relationship between working capital efficiency and profitability of the firms.

Using the help of a set of companies from CMIE Prowess database, the study introduces WCEM as a direct profitability measure of working capital efficiency.

In this study, a new direct measure of working capital efficiency is introduced which is multiplicative in nature. WCEM is a product of three components, namely, WACC, ratio of the sum of trade receivables and inventories to trade payables and ratio of net working capital (NWC) to net sales.

The importance of direct measure like WCEM could be enormous in performance evaluation of a firm. It can be used as an indicator for choosing a suitable investment opportunity by an investor. This is due to the fact that the firm that is highly efficient in managing working capital is less exposed to liquidity risk. At the same time, the firm is less dependent on external financing. Therefore, such firms eventually create more value for their shareholders. Another indication that WCEM provides is to gauge the bargaining power of the firm and its competitive position in the market. Lower WCEM indicates higher bargaining power of a firm across the value chain, and its superior position relative to its competitors.

Most of the studies on WCM are of the empirical type and there is a complete dearth on theoretical framework. Researchers hereafter can consider WCEM as one of the financial performance variables in place of the existing measures such as return on asset (ROA), return on invested capital (ROIC), return on equity (ROE), gross operating income (GOI) and net operating income (NOI) and thereby can contribute new empirical insights through their research outcomes.

The numerical analysis is to scrutinize the collective effect of convective current along with the thermal energy transport in an inclined lid-driven square chamber with sine curve based temperature at the lower wall in the existence of unchanging external magnetic field. Insulation has been placed on the left and right of the box to increase the effective space volume of the shell. The thermal condition at ceiling wall is kept lower than the one on the floor.

The finite volume method employs to discretize (non-dimensional) system of equations govern the model. The heat transfer rate is measured by adjusting various variables, such as the Richardson number Hartmann number, inclination of an enclosure.

The flow behavior of enclosure convection is more highly influenced within the natural convection when enclosure inclination varies as well as magnetic field strength. The overall heat transfer rate decreases due to increase in both the Hartmann number as well as Richardson number.

The results of the present study are very useful to the cooling of electronic equipments.

The study model is useful to the thermal science community and modelling field.

This research is a novel work on mixed convection flow in an inclined chamber with sinusoidal heat source.

This study aims to investigate numerically the impact of the three-dimensional convective nanoliquid flow on a rotating frame embedded in the non-Darcy porous medium in the presence of activation energy. The cross-diffusion effects, i.e. Soret and Dufour effects, and heat generation are included in the study. The convective heating condition is applied on the bounding surface.

The control model consisted of a system of partial differential equations (PDE) with boundary constraints. Using suitable similarity transformation, the PDE transformed into an ordinary differential equation and solved numerically by the Runge–Kutta–Fehlberg method. The obtained results of velocity, temperature and solute concentration characteristics plotted to show the impact of the pertinent parameters. The heat and mass transfer rate and skin friction are also calculated.

It is found that both Biot numbers enhance the heat and mass distribution inside the boundary layer region. The temperature increases by increasing the Dufour number, while concentration decreases by increasing the Dufour number. The heat transfer is increased up to 8.1% in the presence of activation energy parameter (E). But, mass transfer rate declines up to 16.6% in the presence of E.

The applications of combined Dufour and Soret effects are in separation of isotopes in mixture of gases, oil reservoirs and binary alloys solidification. The nanofluid with porous medium can be used in chemical engineering, heat exchangers and nuclear reactor.

This study is mainly useful for thermal sciences and chemical engineering.

The uniqueness in this research is the study of the impact of activation energy and cross-diffusion on rotating nanoliquid flow with heat generation and convective heating condition. The obtained results are unique and valuable, and it can be used in various fields of science and technology.