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Herein, we have developed a tool for monitoring the outdoor performance of dye-sensitized solar cells. In this regard, a new dye consisting of an N-aryl-substituted imidazole with N-alkylated carbazole as the donor and cyanoacrylic acid as the acceptor has been designed. The overall power conversion efficiency of the designed dye reached ∼50%, with respect to that of the N719-based device (4%) under similar experimental conditions. Further, the device was interfaced with an IoT system, which measured the voltage and transmitted the device parameters to the user's mobile phone through a cloud channel. The developed IoT tool provides a resolution of 0.0315 mV and a round-trip delay time of

Free-standing graphene (FSG) paper plays a vital role in a wide variety of applications as an electrode material. Specifically, the electrical properties of FSG are the most important factor affecting its use as an electrode material. Herein, the vacuum filtration technique is utilized to fabricate GO paper, which is then reductively treated with HI. Initially, the electrical conductivity is measured for GO papers with different thicknesses by varying the concentration of GO precursor as well as the reduction time. The FSG paper with a thickness of 3 microns exhibits the lowest sheet resistance and further characterization is carried out to reveal the origin of this enhancement of electrical properties. The low resistance is attributed to its crystalline nature, stacking height (Lc), in-plane crystallite size (La) and defect density (nD). Meanwhile, iodide ions intercalated into the graphene layers act as hole-carriers, and their intercalation is favoured over adsorption at the surface.

The increasing application of nanoparticles both in industries and in agricultural fields has led to its accumulation in the aquatic ecosystem through water run-off. Insights into the validity of safer nanoparticles such as gold and chitosan are fairly established. However, its effect on aquatic invertebrates has been less studied. The present study was aimed to study effects of chitosan reduced gold nanoparticles (CRGNPs) during green fluorescent protein (GFP) encoding plasmid delivery in giant freshwater prawn, macrobrachium rosenbergii. The mean particle size and zeta potential CRGNPs was 33.7 nm and 24.79 mV respectively. Prawn juveniles were exposed to nanoparticles concentrations (10 µg/L, 20 µg/L) of CRGNPs by immersion treatment for a period of 36 hours. GFP was ubiquitously expressed in muscle tissues of prawns. The comet assay indicated dose dependent genotoxicity of CRGNPs in gill, pleopod and muscle tissues which was in conformity with its bioaccumulation pattern in vivo. The highest bioaccumulation of CRGNPs was found in Gills, followed by pleopods and least in muscles. Hence, the toxicological potential of CRGNPs to the environment cannot be denied and demands more research on the particular aspect. The doses standardized in the present study would be helpful in safer nano-gene delivery in aquatic invertebrates and development of transgenics employing less cost.

Magnesium ions incorporated calcium phosphate was synthesized by wet chemical route and followed by microwave assisted method. XRD analysis was confirmed that the presence of calcium phosphate (hydroxyapatite). TEM analysis was exhibited rod-like morphology. XRF results were showed the percentage of calcium, phosphate, magnesium and oxygen. There was a slight blue shift observed in magnesium ions based samples. Higher magnesium (0.1 Mg-HAp) was revealed the greater discharging time with capacitance voltage (0.55 V). Magnesium based calcium phosphate was showed prolonged rate of drug release. At higher frequency, the Nyquist plot was showed the electrochemical behavior, however at lower frequency, revealed mass transfer process. Magnesium ions tailor the specific capacitance of calcium phosphate. Therefore, magnesium ions based phosphate samples could be an outstanding multifunctional candidate for drug release and supercapacitor applications.

Highly catalytic two dimensional and metal-doped two-dimensional nanomaterials (MoS2 and NiMoS) were deposited over free-standing graphene (FSG) paper using electrodeposition method and subsequently used as a counter electrode in quasi solid-state dye-sensitized solar cells (q-DSSCs). The replacement of FTO by FSG facilitates high electrical conductivity and electrodeposited metal sulphides provide electrocatalytic activity. The morphology, structural phase formation and chemical composition of FSG-MoS2 and FSG-NiMoS were investigated using FESEM, XRD, Raman and XPS analysis. The electrochemical behavior of metal sulphide decorated FSG cathodes is investigated using an electrochemical workstation and their effects on the photo-conversion efficiency of DSSCs were assessed. NiMoS with FSG substrate is an intriguing counter electrode material that can be utilized at low fabrication cost than the conventional platinum-based counter electrodes. FSG along with the metallic-two dimensional nanoparticles (NiMoS) functions as an effective catalytic material thereby allowing DSSCs to achieve enhanced efficiency of ∼7% to provide better alternative of FTO and Pt.

Cross-linked polymer (CLP) composed of poly(ethylene glycol) methyl ether acrylate and poly(ethylene glycol) diacrylate has been used in synthesizing gel electrolyte. A set of electrolyte samples was synthesized using gel casting method by varying the weight percentage ratio of cross-linked polymers from 2–14 % in an incremental order (2 %) with respect to poly (ethylene oxide) (PEO) and evaluated its performance by employing in the fabrication of dye-sensitized solar cells. The synthesized polymer was subjected to different analytical techniques such as NMR, TGA, DSC, GPC, and FTIR to confirm the materials. The molecular weight of the CLP has been measured using GPC and the obtained value is found to be 3.655 KDa with polydispersity of 1.94. The CLP-PEO gel electrolyte with 10 % weight ratio has obtained the highest ionic conductivity of 3.07 × 10−6 S/cm−1 at room temperature and best photo-conversion efficiency of 5.1 % was achieved for the same.

In this short communication we report a sensor for divalent mercuric (Hg 2+ ) ions that we constructed from a perylene bisimide (PBI)-based organic thin film transistor. We improved the performance of the n-channel device by positioning N,N′-dioctyl-3,4,9,10-perylenedicarboximide between the dielectric and the active layer (PBI), increasing the electron mobility (μ) from 0.002 to 0.25±0.04 cm 2 V −1 s −1 and enhancing the on/off ratio ( I on / I off ) by two orders of magnitude (from 10 2 to 10 4 ). Based on a “thymine–Hg 2+ –thymine” mechanism and monitoring the shift in the threshold voltage ( V th ), we used this transistor to discriminate Hg 2+ ions from mixed ion solutions and it extended to different concentration Hg 2+ solutions (from 50 to 350 μM). By monitoring the shifts in drain current ( I DS ) and V th , we also used this bilayer device as a sensor for cysteine, a thiol-containing amino acid; the selective detection of cysteine was accompanied by a red shift in the fluorescence maximum of PBI, from 532 to 537 nm.

In this short communication we report a sensor for divalent mercuric (Hg²⁺) ions that we constructed from a perylene bisimide (PBI)-based organic thin film transistor. We improved the performance of the n-channel device by positioning N,N'-dioctyl-3,4,9,10-perylenedicarboximide between the dielectric and the active layer (PBI), increasing the electron mobility (μ) from 0.002 to 0.25±0.04 cm² V⁻¹ s⁻¹ and enhancing the on/off ratio (I(on)/I(off)) by two orders of magnitude (from 10² to 10⁴). Based on a "thymine-Hg²⁺-thymine" mechanism and monitoring the shift in the threshold voltage (V(th)), we used this transistor to discriminate Hg²⁺ ions from mixed ion solutions and it extended to different concentration Hg²⁺ solutions (from 50 to 350 μM). By monitoring the shifts in drain current (I(DS)) and V(th), we also used this bilayer device as a sensor for cysteine, a thiol-containing amino acid; the selective detection of cysteine was accompanied by a red shift in the fluorescence maximum of PBI, from 532 to 537 nm.

Growth economists still face challenges and limitations to incorporate institutions into the standard growth framework. This article develops a simple augmented Solow growth model that accounts for the interactions between institutions and factor-productivity and examine the impacts of the quality of institutions on levels and growth rates of output. The institutions augmented growth model shows that differences in the quality of institutions preclude convergence and determine both the level and the growth rate of output per worker. The model also shows that poor institutions induce poverty traps. Furthermore, the income gap between rich and poor countries will increase if poor countries’ institutions do not improve relative to their rich counterpart.

Using seven alternative measures of the institutions, this study examines the impacts of the quality of institutions on poverty rates in developing countries. The estimates obtained using the instrumental variable method (2SLS) show that the quality of institutions is negatively related with poverty rates and explain a significant portion of the variation in poverty rates across countries. More precisely, the empirical results suggest that an economy with a robust system to control corruption, market-friendly policies, a working judiciary system, and in which people have freedom to exercise their citizenship will create the necessary conditions to promote economic development and reduce poverty. The results suggest that pro-poor policies aimed at reducing poverty should first consider improving the quality of institutions in developing countries as a pre-requisite for economic development and poverty eradication.

The health care delivery system of twenty five OECD nations is analyzed in this paper. This study seeks to assess the significance of various factors contributing to life expectancy and infant mortality for the 1990-2002 period. A fixed-effects panel data model was used to examine the factors influencing life expectancy and infant mortality. More specifically the impact of economic, institutional, and social factors in determining the dependent variables are measured and evaluated.

This paper investigates the possibility of interdependence between flows of US FDI to the ASEAN region. The study incorporates information asymmetry into an FDI model to examine the influence of geographic neighbors on new flows of FDI from the United States. Spillovers are modeled using the cost structure of a multinational investing in a region where US firms are already present. The results show that there are negative spillovers of US FDI in the ASEAN region affecting mostly the non-manufacturing sector.

Over the years, there has been extensive research on the relationship between a country’s export and economic growth with ambiguous and mixed results. Instead of using the conventional cointegration approach, this paper re-examines the export-led growth hypothesis for Kenya using autoregressive distributed lag (ADRL) bounds technique. This approach is capable of testing for the existence of a long-run relationship regardless of whether the underlying time series are individually I(1) or I(0). This enhances the stability and robustness of our results. In addition, we examine the Granger causality between exports and economic growth over the sample period. The results indicate that there exists a long-term relationship between GDP growth and exports, and it is unidirectional, running from exports to GDP growth. Hence, in the case of Kenya, export enhancing policies are recommended in promoting and sustaining economic growth.

The flexible price monetary model assumes that both the purchasing power parity (PPP) and uncovered interest parity (UIP) hold continuously. In addition, the model posits that money market equilibrium exists, which helps to determine the exchange rate. This paper explores exchange rate determination in low-income economies by applying a monetary model to Kenya to examine the exchange rate dynamics in a post-float exchange rate regime. We apply a multivariate cointegration and error correction model (ECM) to investigate whether the long-run exchange rate equilibrium and the rate of adjustment to the long-run equilibrium hold, respectively. Finally, we evaluate the relative performance of ECM versus a random walk framework in the out-of-sample forecasting. We find that the random walk performs better than the restricted model.