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The purpose of this paper is to investigate the ability of transition metals (TMs) of iron-, nickel- and zinc-doped graphene nanosheet for adsorption of toxic gas of nitric oxide (NO). The results of this paper have provided a favorable understanding of the interaction between TM-doped graphene nanosheet and NO molecule.

A high performance of TM-doped graphene nanosheet as a gas sensor is demonstrated by modeling the material’s transport characteristics by means of the Langmuir adsorption and three-layered ONIOM/ density functional theory method. The Langmuir adsorption model has been done with a three-layered ONIOM using CAM-B3LYP functional and LANL2DZ and 6–311G (d, p) basis sets by Gaussian 16 revision C.01 program towards the formation of of NO→TM(Mn, Co, Cu)-doped on the Gr nanosheet.

The changes of charge density for Langmuir adsorption of NO on Mn-, Co- and Cu-doped graphene nanosheet orderly have been achieved as: ΔQ_Co-doped = +0.309 >> ΔQ_Mn-doped = −0.074 > ΔQ_Cu-doped = −0.051. Therefore, the number of changes of charge density have concluded a more remarkable charge transfer for Mn-doped graphene nanosheet. However, based on nuclear magnetic resonance spectroscopy, the sharp peaks around Cu doped on the surface of graphene nanosheet and C19 close to junction of N2 and Co17 have been observed. In addition, Cu-doped graphene sheet has a large effect on bond orbitals of C8–Cu 17, C15–Cu 17 and C16–Cu17 in the adsorption of NO on the Cu-doped/Gr which has shown the maximum occupancy. The amounts of ΔGads,NO→Mn−Co through IR computations based on polarizability have exhibited that ΔGads,NO→Mn−Co has indicated the most energy gap because of charge density transfer from the nitrogen atom in NO to Mn-doped graphene nanosheet, though ΔG(NO→Cu−C)0> ΔG(NO→Co−C)0>ΔG(NO→Mn−C)0.

This research aims to explore the adsorption of hazardous pollutant gas of “NO” by using carbon nanostructure doped by “TM” of iron, nickel and zinc to evaluate the effectiveness of adsorption parameters of various TM-doped graphene nanosheets.

Routing protocol for low-power lossy network (RPL) being the de facto routing protocol used by low power lossy networks needs to provide adequate routing service to mobile nodes (MNs) in the network. As RPL is designed to work under constraint power requirements, its route updating frequency is not sufficient for MNs in the network. The purpose of this study is to ensure that MNs enjoy seamless connection throughout the network with minimal handover delay.

This study proposes a load balancing mobility aware secure hybrid – RPL in which static node (SN) identifies route using metrics like expected transmission count, and path delay and parent selection are further refined by working on remaining energy for identifying the primary route and queue availability for secondary route maintenance. MNs identify route with the help of smart timers and by using received signal strength indicator sampling of parent and neighbor nodes. In this work, MNs are also secured against rank attack in RPL.

This model produces favorable result in terms of packet delivery ratio, delay, energy consumption and number of living nodes in the network when compared with different RPL protocols with mobility support. The proposed model reduces packet retransmission in the network by a large margin by providing load balancing to SNs and seamless connection to MNs.

In this work, a novel algorithm was developed to provide seamless handover for MNs in network. Suitable technique was developed to provide load balancing to SNs in network by maintaining appropriate secondary route.

Presents a new B‐spline finite element for the dynamic analysis of unsymmetrical sandwich shells of revolution. The formulation takes account of the membrane and bending effects in isotropic or orthotropic elastic facings, and membrane, bending and transverse shearing effects in an isotropic or othotropic elastic core. Both geometry and local displacements are interpolated by a set of B‐spline functions. The main aspects added by the sandwich structure of the element are the transverse shearing and membrane‐bending coupling effects in the core. These are well represented by a set of new variables which are the mean end relative in‐plane displacements of the facing middle surfaces. Together with the transverse displacement, these variables constitute the degrees of freedom (dofs) of this new B‐spline sandwich element. The finite elements are grouped into super‐elements with C¹ continuity to obtain the whole finite element model. For each super‐element a total of five dofs per node is then obtained except for its end nodes where the derivatives of these dofs with respect to the meridional co‐ordinate are added. This choice reduces to a minimum the total number of dofs in comparison to existing sandwich elements. Evaluates the efficiency and accuracy of the proposed element through several benchmark examples. Compares the results with the analytical and numerical solutions found in the literature. A very satisfactory behaviour of the element was observed in all test cases.

The purpose of this paper is to examine the joint influence of technological newness (TN) and market newness (MN) on the relationship between customer involvement (CI) and new product performance.

The authors employed hierarchical moderated regression analysis to test the hypothesized relationships using survey data collected from 214 Chinese manufacturing firms.

The authors found that the impact of CI on new product performance varies across the different configurations of TN and MN. Specifically, the performance effect of CI is most positive under low TN and high MN, while the performance effect is least positive under low TN and low MN.

This study enriches CI research by identifying different configurations of product innovativeness that augment or limit the value of CI.

The aim of this work was to propose a method to prepare composite phosphate conversion coating (CPCC), including ternary phosphate conversion coating (TPCC) and binary phosphate conversion coatings (BPCC), with one-step chemical conversion and to reveal and compare the corrosion resistance between TPCC and BPCC.

In this work, a calcium–manganese–zinc (Ca–Mn–Zn) TPCC was prepared on the surface of magnesium alloy (MA) AZ91D with one-step chemical conversion method; for Ca-Mn-Zn@TPCC, its microstructure was characterized with scanning electron microscope observation and scanning tunneling microscope detection, and its composition was characterized with energy dispersion spectroscopy and X-ray photoelectron spectroscopy analyses. Particularly, the corrosion resistance of Ca-Mn-Zn@TPCC and its comparison with Ca–Mn, Ca–Zn and Mn–Zn BPCCs were clarified with electrochemical and immersion measurements.

Ca-Mn-Zn@TPCC, which was composed of Ca, Mn, Zn, P and O, exhibited a mud-shaped with cracks microstructure, and the average crack width, terrain fluctuation and coating thickness were 0.61 µm, 23.78 nm and 2.47 µm, respectively. Ca-Mn-Zn@TPCC provided good corrosion resistance to MA AZ91D; in NaCl solution, the total degradation of Ca-Mn-Zn@TPCC consumed eight days; corrosion products with poor adhesion peeled out from Ca-Mn-Zn@TPCC-coated MA AZ91D spontaneously. Besides, the corrosion resistance of Ca-Mn-Zn@TPCC was better than that of Ca-Mn@BPCC, Ca-Zn@BPCC or Mn-Zn@BPCC.

The successful preparation of Ca-Mn-Zn@TPCC on MA AZ91D surface confirmed the proposed method to prepare CPCC with one-step chemical conversion was feasible; at the same time, it was further confirmed that for phosphate conversion coating, ternary coating had better corrosion resistance than binary coating did.

The purpose of this paper is to investigate of the effects of Mn nanoparticle addition on the wettability, microstructure and microhardness of SAC0307-xMn(np) (SAC: Sn–Ag–Cu; x = 0, 0.02, 0.05, 0.1 and 0.3 Wt.%) composite solders.

The SAC0307-xMn(np) composite solders were prepared by mechanically mixing different weight percentages of Mn nanopowders into the SAC0307 solder paste with rosin flux. In this study, the wettability of the solders was studied using contact angle and spread ratio methods. Afterward, the microstructure of the solders was investigated using scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffractometry. Moreover, the microhardness of the solders was studied.

The wetting process of SAC0307-xMn(np) composite solders was found to experience four stages. Adding a small amount of Mn nanoparticles (x = 0.05 Wt.%) could improve the wettability compared to Mn-free solder. Beyond this level, the wettability deteriorated. The addition of Mn nanoparticles significantly refined the size and spacing of Ag₃Sn grains in the solder matrix. When 0.1 Wt.% Mn nanoparticles was added, both the average size of the Ag₃Sn grains and the spacing between the Ag₃Sn grains decreased significantly and approached minimum values. Beyond this amount, the size and spacing between Ag₃Sn grains increased slightly but remained smaller than those in the Mn-free solder matrix. The refined Ag₃Sn grains increased the microhardness of the Mn-containing composite solders by 6-25 per cent, in good agreement with the prediction of the classic theory of dispersion strengthening.

The paper demonstrates that Mn nanoparticle addition could improve the SAC0307-xMn(np) solder wettability and reduce the grain size and spacing between Ag₃Sn grains. The enhancement of the solder microhardness shows good correlation with the microstructure.

The purpose of this paper is to enhance the corrosion resistance of Cr-Mn austenitic stainless steel (ASS) via low temperature salt bath nitriding and to replace the convectional Cr-Ni ASS with newly developed enhanced corrosion resistive Cr-Mn ASS.

The low temperature salt bath nitriding was performed on Cr-Mn ASS at 450°C for 3 h in potassium nitrate salt bath.

The present paper compares the corrosion resistance of salt bath nitrided Cr-Mn ASS with convectional Cr-Ni ASSs (316 L and 304 L ASSs) in 3.5 per cent NaCl by electrochemical techniques. The electrochemical impedance spectroscopy result shows the increase in film resistance and potentiodynamic polarization results show the enhanced corrosion resistance of nitrided Cr-Mn ASS, which is almost equivalent to that of 316 L and 304 L ASSs. This is attributed to the formation of nitrogen supersaturated dense nitride layer. The present results therefore suggest that the nitrided Cr-Mn ASS may replace costly convectional Cr-Ni ASSs for commercial and industrial applications.

Ever-increasing price of nickel (Ni) is driving the industries to use Ni-free or low-Ni austenitic stainless steels (ASSs). But its corrosion resistance is relatively poor as compared to conventional Cr-Ni ASSs. However, its corrosion resistance can be improved by nitriding. The low temperature salt bath nitriding of Cr-Mn ASS and its electrochemical behavior in 3.5 per cent NaCl has not been studied. The present research paper is beneficial for industries to use low cost Cr-Mn, enhance its corrosion resistance and replace the use of costly conventional Cr-Ni ASSs.

Mobility management for single‐hop cellular networks has received much research attention in the last few years. One of the research challenges for 4G wireless systems is the design of mobility management techniques that integrate cellular and ad‐hoc networks. Currently, there are no structured mobility management schemes for these heterogeneous multi‐hop networks. This paper aims to address these issues.

This paper describes techniques for tracking a mobile node (MN) in an integrated architecture with minimum overhead. This paper proposes group rerouting concept.

The paper implements and evaluates the proposed protocol by using the network simulator (NS‐2). The proposed protocol increases performance compared to broadcasting schemes.

This scheme considers devices with two interfaces only.

The paper proposes a scheme to extend the coverage of cellular base stations by using ad‐hoc devices.

This paper describes techniques for tracking an MN in an integrated architecture with minimum overhead. This scheme is independent of the routing protocol used in a multi‐hop network.

Adopting an entrepreneurial orientation is accepted as strategy through which to improve the performance of small firms. The management of innovation literature indicates that firms seeking to survive in rapidly changing and/or highly competitive markets are being advised to consider participating in business networks. By combining these two concepts it is hypothesised that four different marketing styles may exist; namely conservative/transactional, conservative/network orientated, entrepreneurial/transactional and entrepreneurial/network orientated firms. A survey of small manufacturing firms was undertaken in an attempt to determine whether these four marketing styles exist. The survey revealed that high growth entrepreneurial firms tend to participate in business networks. Membership of a network confers the benefit of increasing the level of organisational learning. Additionally it was concluded that higher levels of competence were found for entrepreneurial/network orientated organisations. The implications of these findings are discussed in relation to Government small firms support policies.