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Hydrodynamics in stirred vessels is vital for transport phenomena for various applications in chemical and environmental systems like aerobic and anaerobic systems, effluent treatment and biological applications like bioreactors. Design of efficient impellers reduces power consumption which contributes to reduction in greenhouse gases especially power obtained from thermal power plants thus decreasing the carbon footprint. In the present work, Computational Fluid Dynamics (CFD) simulations have been carried out for two different Rushton turbines (one axial and one radial flow) for two different height to diameter (H/T) ratio. The model is first validated for a Pitched Blade Turbine Downflow (PBTD) impeller with data available in the literature. A qualitative study of the flow patterns in stirred tanks shows good axial and radial flow profiles for the respective impellers. A decrease in H/T showed higher power consumption for both impellers. The power number (Np) for these impellers has also been calculated for two H/T ratio and Reynolds number (Re) in the range (2500 < Re < 1000. Np was found to be a strong function of liquid level for both impellers considered in the study. Interesting trends of variation of Np with Re have been observed which suggest there is a critical Re where the impellers have least power consum

The e-commerce business has grown significantly over the past few years, mainly due to providing a better customer experience through advance booking and order cancellation options with a full refund. In this paper, the inventory control problem of a firm that offers advance booking for the product and cancellation (with a full refund) before the due delivery date is addressed. A profit maximization model is formulated to find the optimum inventory cycle length, the selling price of the product, and advertisement expenditure. The discounted cash flow approach is used to take into account cash flows at different time points. Advance booking is made at the beginning of the inventory cycle at a discounted price until the time of stock arrival, followed by usual spot sales. The number of order cancellations during the advance booking period is dependent on the waiting time for receiving the order. The impact of revenue collected through advance sales is considered by including interest earned. Product demand is assumed to be the function of advertisement expenditure and the selling price of the product. A solution procedure is suggested, and the model is illustrated through numerical analysis, thereby providing valuable managerial insights based on the results obtained.

Flexible and stretchable supercapacitors developed on MXene‐enabled Titanium Carbide (TiC) impurities‐based electrodes with novel electrolytes are the point of focus in this work. Five different electrodes are prepared with different TiC content and symmetric supercapacitors are fabricated with three electrolytes named acrylamide, N,N′‐Dimethylacrylamide, and 2‐Hydroxyethyl methacrylate to achieve flexibility and improved energy storage. Before electrode fabrication, all the samples are tested with the X‐ray Diffraction technique. Cyclic voltammetry is performed at a potential window from −1 to 1 V to evaluate the specific capacitance of fabricated supercapacitors at multiple scan rates. Electrochemical impedance spectroscopy is performed to study the Randles circuit, and Rs values are calculated to examine the maximum physical area used for the evaluation of supercapacitors. Open‐circuit and short‐circuit tests are performed after charging the capacitor at 1 V for 2 min each time and compatibility of electrodes with different electrolytes is analyzed. The figures of merits for all the techniques used are discussed in detail. The highest values of the specific capacitances reported in our work are 50 and 79 F/g with novel electrolytes termed as N,N′‐Dimethylacrylamide and 2‐Hydroxyethyl methacrylate, respectively. [ABSTRACT FROM AUTHOR]

This study focuses on the large-scale production of a high-energy-density supercapacitor through the cost-effective polymerization of a PANI/Cr2O3/graphene nanocomposite, utilizing commercially available flexible substrate and cost-effective chemicals. To explore the synergistic effect, a PANI/Cr2O3/graphene nanocomposite is evaluated in a hybrid gel electrolyte with varying polyvinyl alcohol (PVA) concentrations. The investigation is aimed at enhancing the electrochemical performance of electrode material for supercapacitors. Two symmetric devices are fabricated to assess the specific capacitance and energy density of the prepared nanocomposite. In the PVA2g/Na2SO4 electrolyte, the energy density is increased to 61.71 Wh kg−1, accompanied by an enhanced potential window of 1.95 V. Furthermore, the prepared composite demonstrates good electrochemical stability, retaining 94% of its initial capacitance after 2000 cycles at 2 Ag−1 in 2 g PVA/Na2SO4 gel electrolyte. The remarkable electrochemical properties of the composite can be attributed to the effective contact and synergistic effect among PANI, Cr2O3, and graphene, making it a promising candidate for supercapacitor applications. Moreover, this facile process is easily scalable to meet commercial demands and can be utilized to enhance the energy density of various carbon-based materials with limited initial performance. [ABSTRACT FROM AUTHOR]

We report a cost-effective, chemical polymerization route to synthesize PANI/Co3O4/graphene (PCG) ternary nanocomposite for supercapacitor applications to achieve enhanced energy density in a cost-effective, non-toxic, and non-corrosive neutral aqueous electrolyte of 1M Na2SO4. These properties are advantageous for a supercapacitor assembling procedure, being favorably facile and inexpensive. The electrochemical analysis was carried out to check analyte performance with cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). The PCG ternary nanocomposite exhibits a specific capacitance of 183 F g−1 at 1 A g−1 in a two-electrode device, and retains its 93% of initial specific capacitance after 2000 cycles. The energy density of PCG ternary nanocomposite is 49.81 Wh Kg−1 with a power density of 697.72 W Kg−1. The excellent electrochemical properties of the PCG ternary nanocomposite are credited to the good contact and the synergistic effect between the PANI nanofibers, Co3O4 nanoparticles, and graphene nanosheets. This indicates that this synthesized ternary nanocomposite material could be used as a promising candidate for supercapacitor electrode material. [ABSTRACT FROM AUTHOR]

Object recognition and Localization is an important problem in computer vision and robotics. Advances in computer vision has resulted into many object recognition techniques but most of them are computationally very heavy and requires robot unit to have high processing systems. When it comes to small size embedded robotic systems, these techniques can not be applied because of the constraints of execution time. Here, a popular SURF based recognition technique is adopted and some of the important changes are addressed which make it possible to use it on small size robots with limited resources. A team of small robots are used which are given prior training to search for 2D and 3D objects of interest in the environment. For the localization of the robots and objects a new template, designed for passive markers based tracking, is introduced. These markers are placed on the top of each robot and they are tracked by the two ceiling mounted cameras. The information from ceiling mounted cameras and from the team of robots is used collectively to localize the object of interest in the environment.

Economic ties between Pakistan and China were developed from 1959 through Shahrah e Korakoram and the instigation of CPEC project has efficiently enhanced the economic and strategic ties between neighboring countries. However, outbreak of COVID-19 has posed various questions regarding the future prospects of CPEC and its significance especially for Pakistan. In fact, Pakistan and China both have worked together to devise strategies to deal with the prevailing issues. Though Pakistan was also surrounded by issues associated with balance of payments and pressure was also raised from IMF and FATA. However, there are some blessings also for the country as COVID-19 might also give Pakistan unexpected economic relief which may not only benefit CPEC but also Pakistan’s economy. Therefore, to have realistic view regarding the impact of COVID-19 there is a need of thorough and proper research so as to have final stance regarding the issue. Though lack of authentic data regarding investment of CPEC as well as economic relief and COVID-19 are hindering in research and policy formulation, therefore, the focus of this study is towards the assessing of effect of COVID-19 on CPEC through the opinion of leading economists. The data was analyzed through SMART-PLS which indicated that COVID-19 is producing significant positive impacts economically and socially. [ABSTRACT FROM AUTHOR]

In this work, we report the design and successful synthesis of two new heteroleptic polypyridyl Ru(II) complexes (SD-5 and SD-6), by incorporating hetero-aromatic electron-donating N-alkyl-2-phenylindole moieties into the ancillary ligand. These novel ruthenium complexes were used as photosensitizers for dye-sensitized solar cells. The primary objective was to investigate the electron-donating effect of the indole segments on the photo-related properties and the influence of the length of terminal alkyl chains tethered to N-indole on the charge recombination resistance. The chemical structures of both targeted compounds were confirmed via FT-IR, 1H-NMR and mass spectrometry. Under the same device fabrication conditions, the photovoltaic performance of SD-6 outperformed that of SD-5 and N719 with an overall efficiency of 8.14% (JSC = 19.21 mA cm−2, VOC = 0.675 V and FF = 62.7%), compared to 7.74% of N719 and 4.99% of SD-5. The enhanced photovoltaic power of SD-6 can be attributed to the presence of long alkyl antennas (–C18H37) in SD-6; it reduced the intermolecular aggregation of dyes and suppressed charge recombination, thus resulting in enhanced JSC and VOC values, respectively, compared to its analog SD-5. Furthermore, the presence of indole moieties with long alkyl chains in the ancillary ligand enhanced the photovoltaic performance compared to N719 with bi-anchoring ligands. The photovoltaic and EIS measurements were consistent with the equilibrium molecular geometry calculated using density functional theory (DFT). The structure–property relationships have been discussed in detail. [ABSTRACT FROM AUTHOR]

The demand for miniaturization of electronic devices has lent to the development of graphene-based hybrid structures, which include the Metal-Semiconductor-Metal (MSM) device. In this work, one has developed such a device by growing monolayers of graphene on top of Nickel to form the basic structural matrix. Four different variants of the MSM unit structures have been developed to assess their potential in next generation electronics. The presence of graphene in the original matrix was confirmed via Atomic Force Microscopy, and the optical response of the graphene layer was further studied using Spectroscopic Ellipsometry in UV-Vis-NIR regime; Forouhi-Bloomer model was used to analyze the ellipsometry data. Hall effect and other electrical characterization measurements were conducted to analyze the electrical properties of the fabricated devices. [ABSTRACT FROM AUTHOR]

The Technology Acceptance Model (TAM) is a simplistic information system. The improved features of new technology strongly impact the consumer's use of it. The objective of the research was to develop TAM for online banking in Pakistan. This research was the primary research wherein data was collected from five hundred respondents which were students of universities of private and government sector (Islamabad/Rawalpindi cities) through questionnaires. Correlation and regression tests were conducted via SPSS software; correlation analysis showed that a significant positive relationship exists without ethics among all the factors. In regression analysis value of R2 = 0.621 it indicates that every independent variable has 62% impact on dependent variable, model has capability to predict future results of research. The research result suggested that ethics and ethical values are the main hurdles in adoption of the mobile banking in Pakistan. The research findings will help the business managers and related organizations to reconstruct their business strategies in order to capture and retain the maximum potential customers. [ABSTRACT FROM AUTHOR]

Until recently, Gwadar has always been mentioned as a small insignificant fishing town. Very little was known about its history and potential to the outside world. However, at the turn of the 21st century Gwadar became the focus of attention globally. The development of a deep seaport with China's assistance and prospects of connecting China and Central Asia through Pakistan to the North Arabian Sea has brought this small, insignificant fishing town to international recognition. But history reveals that this region has always played a vital role since primeval times due to its geostrategic and geographical location. From Alexander's retreat to Pakistan's reclaiming Gwadar, it has always reminded its significance at different times in diverse manners. This paper aims to bring into light the historical journey of Gwadar, which usually remained unknown or were either considered trivial by historians. Gwadar became an important chapter in the Belt and Road initiative proposed by the Chinese president. It will link China, South Asia, Middle East, Central Asia, Africa and Europe through a network of land and sea routes and ports will contribute significantly to the progress and prosperity of Gwadar in Pakistan, China and the entire region. [ABSTRACT FROM AUTHOR]

In Pakistan, rural areas of the Sindh province are the most distressed areas regarding the graduate females who are working in all the public and private sectors. Females don't have their spoken sound or free opinion; even they are not given the right to choose and select anything regarding their profession. This research paper examines the difficulties of working graduate females in rural areas of the Hyderabad district. The quantitative research method was applied, and the survey was conducted through the research questionnaire depended upon the Likert scale 5.0. A sample of 100 working graduate females was selected from three public and private sectors as 50 school and college teachers, 10 Doctors, 15 health workers, and nurses, and 25 working graduate females from the banking sector using stratified random sampling. Given outcomes of the research; The working females faced social, cultural, and domestic problems in the public and private sectors. Problems associated with nurses and banker graduates are facing long and unpredictable working hours, low social status, and no job recognition. Most respondents have no job security, receiving insufficient salaries, and facing gender discrimination. So, there is a need for a policy regarding working hours and there is a need to change the negative approaches of society through providing awareness programs on media. [ABSTRACT FROM AUTHOR]

This paper explores the religious ideological basis, cultural ambivalence and a bicultural identity issues in Mohsin Hamid's The Reluctant Fundamentalist. This Pakistani Anglophone novel carries different diasporic sensibilities. Issues related to culture, religion and its association with ideological grounds are very prominent. Elements of immigrant feelings and loss of identity are very vibrant. The writer shares migrant experience and the influence of a new culture of the host country, United States. While migrants from some of the Asian states, mainly those characterized by most recent immigrant waves, have really worse socio-economic situation than average immigrants; Pakistani people are among minorities. This research is qualitative in nature. Theories presented by Arjun Appadurai, Homi K Bhabha, and James Clifford about culture and diaspora support this research. This research is helpful to know about the concerns associated with the liminal space and issues related to identity loss, strong affiliation and recognition on the basis of religion and living with a bicultural identity. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyze the performance of mansabdari system under the successors of Emperor Jalaluddin Muhammad Akbar. The paper is focused on the mansabdari system which was developed and strengthened during the reign of Akbar. It can be argued that the mansabdari was an integrated system of efficient and loyal servants on the disposal of Akbar for the large expansion of his empire. The successors of Akbar tried to capture the spirit of Akbar’s age and reign in all respects but without much success. The system remained intact with central authority during Akbar’s days. The paper indicates that after the death of Akbar, the mansabdars started defying the authority of governors as well as the successors of Akbar. In this research attempt the performance of mansabdari system under the successors of Akbar i.e. Jahangir, Shah Jahan and Aurangzeb will be analyzed. The aim of this paper is to analyze the performance of mansabdari system under the successors of Emperor Jalaluddin Muhammad Akbar. The paper is focused on the mansabdari system which was developed and strengthened during the reign of Akbar. It can be argued that the mansabdari was an integrated system of efficient and loyal servants on the disposal of Akbar for the large expansion of his empire. The successors of Akbar tried to capture the spirit of Akbar’s age and reign in all respects but without much success. The system remained intact with central authority during Akbar’s days. The paper indicates that after the death of Akbar, the mansabdars started defying the authority of governors as well as the successors of Akbar. In this research attempt the performance of mansabdari system under the successors of Akbar i.e. Jahangir, Shah Jahan and Aurangzeb will be analyzed. [ABSTRACT FROM AUTHOR]