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Back-contact modification using a 10-nm ZnS layer in CZTSSe-based solar cell can play a crucial role in improving photovoltaic conversion efficiency. An ultrathin layer of ZnS is deposited over Mo-coated soda lime glass substrate before depositing CZTSSe using sputtering. The crystal structure of deposited CZTSSe thin films over ZnS is recognized as (112)-oriented, polycrystalline in nature, and free from the presence of any secondary phases such as Cu2(S,Se) or Zn(S,Se). The bandgap of CZTSSe thin films deposited over ultrathin ZnS is observed to increase from 1.49 (deposited over Mo directly) to 1.58 eV at room temperature, as determined by spectroscopic ellipsometry. In addition, numerical simulation has been performed using SCAPS software. The impact of ZnS layer has been simulated by using the defects in the absorber and at the interface of ZnS/CZTSSe. The simulated results have been validated with experimentally fabricated CZTSSe device. Simulated device with ZnS intermediate layer is observed to give rise to a photovoltaic conversion efficiency of 15.2%.

In this work, fabrication of CdZnO/ZnO-based multiple quantum wells (MQWs) by dual ion beam sputtering (DIBS) is optimized based on different deposition temperature and halt time between deposition of consecutive layers to achieve improved quality deposition of well and barrier layers for solar cell application. The effect of deposition temperature and halt time are analyzed and discussed systematically by secondary ion mass spectroscopy (SIMS) and high-resolution transmission electron microscopy (HR-TEM). The results show that, MQWs structure fabricated at 100 °C as deposition temperature and having halt time of 30 min, shows better formation of well and barrier layers compared to other deposition temperatures and halt time.

Mixing constitutes a critical design parameter in solid-state fermentation (SSF) bioreactor and its effect on heat and water transport, and microbial growth in substrate bed can significantly influence overall productivity. Effect of mixing events on the production of a thermo-tolerant and acid stable phytase, by Rhizopus oryzae, was studied in a novel SSF bioreactor, using optimized growth medium containing wheat bran and linseed oil cake (1:1) as main substrate. A critical mixing phase was identified, in the absence of which fungal growth led to the onset of heat accumulation and subsequent bed drying. The tensile strength of hyphal bonds between two substrate particles, at this critical phase, was estimated and related to the mixing intensity in the bioreactor that resulted in an optimum working value of 15 rpm. Effect of mixing time on bioreactor performance was also investigated where a 3 min mixing duration, at every 6 h, increased biomass and phytase productivity to 2.2- and 4.5-fold, respectively, in comparison to packed bed bioreactor (PBR). The proposed bioreactor system with intermittent mixing gave superior performance than PBR and tray bioreactor, in terms of maximum bed temperature, axial bed temperature and biomass gradient, average bed moisture content, biomass and phytase productivity.

Major urban corridors in Indian cities are carrying significantly high traffic leading to near saturated conditions for extended peak hours. As mixed landuse and major trip attracting/generating establishments are generally observed to be located along such corridors for better accessibility, significant side friction is also observed along these corridors. Among various measures to improve the throughput along such corridors, signalized intersections seem to be the most preferred intervention for intersection control. Although frequent occurrence of such traffic signals and non-coordinated signal phases have in turn made the whole situation more complex. To overcome this challenge, variations of smart signals are being proposed by technology and traffic enterprises globally. Generally, smart interventions in operation of signalised intersections require communication among vehicles and control system through various sensors and applications of Intelligent transport services (ITS). Smart signal operations require the sensors grouted in pavement or attached with camera to share the relevant data in real time basis with central command and control centre. With adaptive signal operations, it is attempted to schedule signal phases in such a way that green phase of every cycle generally experiences near saturated flow conditions. The smart cities mission (SCM) of India, covering around 100 cities also focuses upon improving the urban mobility through various measures including smart signals. Some of the popular proposals relating to smart operation of signalised intersection across shortlisted smart cities include adaptive and coordinated traffic signals. It is understood that traffic signal optimization is not a one-time action but rather a continuous process, as data archiving, data crunching, research and adaptations are indispensable for its success. As the geometry, location and setting of each intersection in every network is bound to be unique, the optimization process needs to consider the same. The literature and case study of Indian city Bhubaneswar (ranked first in nationwide smart city challenge) revealed that challenges specific to Indian driving conditions are major cause of worry for yielding stated benefits of smart signals. Factors like varying hierarchy and functions along major arterial corridors, fluctuating carriageway width and quality, considerable side friction within right of way, heterogeneity in vehicular mix, significant variation in peak hour directional flows leading to tidal flow, surrounding network characteristics and efficacy of optimisation techniques are responsible for limited rewards out of the whole process. The study reflects upon these challenges and concludes with recommendations to improve the performance of signalized intersections along corridors with heterogeneous traffic conditions.

The addition of surfactant during hydrothermal growth greatly affect the surface morphology of nanostructures [1]. Here, to see the impact of surfactant in the hydrothermal growth of WO3 nanostructures, we have used Cetyl trimethyl ammonium bromide (CTAB) and Sodium chloride (NaCl) as surfactants during WO3 nanostructure formation. Flower-like WO3 nanostructure were successfully grown by CTAB surfactant while nanorod-like structures were obtained in the presence of NaCl at an optimized pH level. Na2WO4·2H2O salt was used with CTAB and NaCl surfactant separately in acidic (HCl (3M)) medium for the hydrothermal growth. The shape of nanostructures plays a crucial role for gas sensing [2]. WO3 nanorods grown by NaCl surfactant exhibited excellent sensitivity for NO2 at ppm level as compared to WO3 nanoflowers grown CTAB surfactant. In addition to the surface area, current conduction also depends on the surface morphology which is helpful to improve the response-recovery characteristics of the sensing device. Interestingly, we observe that hydrothermally grown WO3 with NaCl surfactant is an ideal candidate for NO2 sensing. Fig. 1 FESEM image of WO3 nanostructure with (a) CTAB surfactant, (b) NaCl surfactant and (c) exhibit the sensitivity of WO3 with NaCl and CTAB surfactant at 150 °C on 100 ppm NO2 . Figure 1

This research work addresses issues of video trans-smission and presented a model that is used for transmission of video with the help of UDP Lite protocol. Before transmission of video, we are compressing the video by bitwise operator. This model is work for MJPEG format. The basic idea of this proposed model is that firstly we select the file which is in the form of video. Generally, in the computer network all the data is in the form of packets or 0s or1s. These packets are then compressed using bitwise operator. After compressing the packets, we will use the transport protocol that is UDP Lite Protocol. In the UDP Lite protocol checksum is used for reducing the packet loss and in this model we use a program which is called an Error Trace Program by which we can know if there is any loss of packet. Generally, we can increase the number of packets in an individual block by doing compression but only disadvantage is that some of the packets are lost. Nowadays a number of audios, videos, images files are increasing continuously on internet. During transmission of these files, sometimes bits are losses by many reasons and quality of data is reduced [1], [2]. So, this work improves the quality of data and increase the performance during transmission of data by managing the packets.

In this paper, the work of quantum computing and how this technology is helpful in developing future high speed processing reversible logic gates with the help of QCA. This paper describes the various reversible gates in brief by using quantum dot cellular automata. Simulation result and design of Feynman Gate is projected with the use minimum number of quantum cells in multilayer which facilitate the circuit to add more combinatorial circuit in parallel when required corresponding to the Feynman. Several researchers focuses their research on design and synthesis of efficient reversible logic gates. This paper presents the study of quantum computing and combinational circuit of some basic reversible logic gates verified through simulation using QCA designer.