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Article
Publication date: 31 March 2020

Chunlan Liu, Yang Gao, YaChen Gao, Yong Wei, Ping Wu and Yudong Su

This paper aims to clarify the relationship between the performance of the metal nanoparticles and the sensitivity of the fiber surface plasma resonance (SPR) sensor. It…

Abstract

Purpose

This paper aims to clarify the relationship between the performance of the metal nanoparticles and the sensitivity of the fiber surface plasma resonance (SPR) sensor. It proposes modeling the sensing effects of a single-mode fiber SPR sensor with a cone angle structure decorated with metal nanoparticles. This study uses the metal nanoparticles to the realize enhanced sensitivity of refractive index sensing.

Design/methodology/approach

This paper opted for an exploratory study using a simulation approach of finite-difference time-domain (FDTD). Specifically, the effect of size, the material and the shape of the metal nanoparticle on sensing performance are investigated theoretically.

Findings

In conclusion, it is evident that the localized SPR (LSPR) effect weakens as the diameter of the gold nanosphere increases, the SPR effect enhances and the SPR sensitivity increases first and then decreases. The metal nanoparticle with the different materials and different shapes also have different LSPR and SPR sensitivity and wavelength length dynamic range. The investigation shows that, by changing parameters, the reflection spectra of the fiber SPR sensor exhibit an obvious transition from LSPR to SPR characteristics, and enhanced sensitivity of the refractive index is realized.

Originality/value

This paper fulfills an identified need to study how the sensitivity of the fiber SPR sensor can be enhanced by the metal nanoparticle. After the optimization of parameters, the sensitivity of 5,140 nm/RIU is achieved, which provides a new research direction for sensitivity enhancement of fiber SPR sensor.

Details

Sensor Review, vol. 40 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 30 November 2018

Chunlan Liu, Yong Wei, Yudong Su, Hao Liu, Yonghui Zhang and Xiangfei Nie

This paper aims to propose and demonstrate a novel surface plasmon resonance (SPR)-sensing approach by using the fundamental mode beam based on a graded index multimode…

Abstract

Purpose

This paper aims to propose and demonstrate a novel surface plasmon resonance (SPR)-sensing approach by using the fundamental mode beam based on a graded index multimode fiber (GIF). The proposed SPR sensor has high sensitivity and controllable working dynamic range, which expects to solve the two bottlenecks of fiber SPR sensor, including low sensitivity and the difficulty in multichannel detection.

Design/methodology/approach

The low-order mode of the GIF to SPR sense, which keeps the sensitivity advantage of the single-mode fiber SPR sensor, is used. By using this new SPR sensor, the effect of light incident angle and gold film thickness on working dynamic range was studied. According to the study results, the smaller is the incident angle, the larger is the SPR working dynamic range and the longer is the resonance wavelength with a fixed gold film thickness; the larger is the gold film thickness, the longer is the resonance wavelength with a fixed grinding angle. After the parameter optimization, the sensitivity of these two parameter-adjusting methods reach 4,442 and 3031 nm/RIU.

Originality/value

When the grinding angle of the GIF increases, the dynamic range of the resonance wavelength increases and has a redshift, sensitivity increases, and the resonance valley becomes more unobvious with a fixed gold film thickness. Similarly, when gold film thickness increases, the dynamic range of the resonance wavelength increases and has a redshift, sensitivity increases, and the resonance valley becomes more unobvious with a fixed grinding angle. These adjusting performance aforementioned lay the foundation for solving of the fiber-based SPR multichannel detection and increasing of the fiber-based SPR sensor sensitivity, which has a good application value.

Details

Sensor Review, vol. 39 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 4 August 2021

Tarek Rana, Zahir Uddin Ahmed, Anil Narayan and Mingxing Zheng

This paper aims to examine new public management (NPM) reform in New Zealand Universities (NZUs) and the process by which government policy changes generated service…

Abstract

Purpose

This paper aims to examine new public management (NPM) reform in New Zealand Universities (NZUs) and the process by which government policy changes generated service performance reporting (SPR), and how the SPR practices were institutionalised. It seeks to explain the underlying institutional forces of the reform process, how universities were subjected to accountability pressures through government-imposed managerial techniques and how universities responded to them.

Design/methodology/approach

The authors draw on the theoretical lens of neo-institutional theory and the concept of NPM to interpret the setting of SPR. Data comprise annual reports and other documents produced by the NZUs.

Findings

The findings show that the development of the SPR was driven by NPM ideals and rationales of greater transparency and accountability. The institutional pressures bestowed extra power to the government by demanding greater accounting reporting of university performance. It also shows the ensemble of institutions, organisations and management practices that were deployed to reorganise performance reporting practices.

Research limitations/implications

The study adds to the neo-institutional theory work that universities are experiencing extraordinary institutional pressure to become a market-type commodity in New Zealand and internationally. The findings have implications for government, universities, policymakers and public sector professionals who work in public sector reform.

Originality/value

Through the institutional theoretical lens, the study offers new insights into our understanding of NPM-driven regulation and institutionalisation of managerial techniques. The insights inform policy and practice surrounding design, implementation and the potential effect of future policy changes with reference to the performance of NZUs and internationally.

Details

Journal of Accounting & Organizational Change, vol. 18 no. 3
Type: Research Article
ISSN: 1832-5912

Keywords

Article
Publication date: 9 September 2013

Yap Wing Fen and W. Mahmood Mat Yunus

The purpose of this paper is to review the novel application of surface plasmon resonance (SPR) in sensing heavy metal ions and the development of SPR to become an…

Abstract

Purpose

The purpose of this paper is to review the novel application of surface plasmon resonance (SPR) in sensing heavy metal ions and the development of SPR to become an alternative heavy metal ions sensor.

Design/methodology/approach

The possible dangerous toxic effects of heavy metal ions are revealed in the short introduction. The existing conventional methods for sensing heavy metal ions and their drawbacks are also discussed. To overcome these drawbacks, SPR has been investigated from the basic principle to the potential alternative in sensing heavy metal ions.

Findings

Application of SPR in sensing heavy metal ions emerged a decade ago. A wide range of active layers or recognition elements (e.g. polymer, protein, nanoparticles) have been developed to combine with SPR. The detection limit, sensitivity and selectivity of SPR sensing in heavy metal ions have been improved from time to time, until the present.

Originality/value

This paper provides up-to-date and systematic information on SPR sensing for heavy metal ions. Different advancements on active layers or recognition molecules have been discussed in detail and arranged in the order of their chronological evolution. The present review may provide researchers with valuable information regarding novel heavy metal ions sensor using SPR and encourage them to take this area for further research and development.

Details

Sensor Review, vol. 33 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 4 November 2014

Mica Grujicic, Jennifer Snipes, S. Ramaswami and Fadi Abu-Farha

The purpose of this paper is to propose a computational approach in order to help establish the effect of various self-piercing rivet (SPR) process and material parameters…

Abstract

Purpose

The purpose of this paper is to propose a computational approach in order to help establish the effect of various self-piercing rivet (SPR) process and material parameters on the quality and the mechanical performance of the resulting SPR joints.

Design/methodology/approach

Toward that end, a sequence of three distinct computational analyses is developed. These analyses include: (a) finite-element modeling and simulations of the SPR process; (b) determination of the mechanical properties of the resulting SPR joints through the use of three-dimensional, continuum finite-element-based numerical simulations of various mechanical tests performed on the SPR joints; and (c) determination, parameterization and validation of the constitutive relations for the simplified SPR connectors, using the results obtained in (b) and the available experimental results. The availability of such connectors is mandatory in large-scale computational analyses of whole-vehicle crash or even in simulations of vehicle component manufacturing, e.g. car-body electro-coat paint-baking process. In such simulations, explicit three-dimensional representation of all SPR joints is associated with a prohibitive computational cost.

Findings

It is found that the approach developed in the present work can be used, within an engineering optimization procedure, to adjust the SPR process and material parameters (design variables) in order to obtain a desired combination of the SPR-joint mechanical properties (objective function).

Originality/value

To the authors’ knowledge, the present work is the first public-domain report of the comprehensive modeling and simulations including: self-piercing process; virtual mechanical testing of the SPR joints; and derivation of the constitutive relations for the SPR connector elements.

Details

Multidiscipline Modeling in Materials and Structures, vol. 10 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 1 February 2013

Hamid R. Aghayan, Evgueni V. Bordatchev and Jun Yang

The purpose of this paper is to develop new knowledge in experimental characterization of contaminants in engine lubricants, using surface plasmon resonance (SPR) sensing…

Abstract

Purpose

The purpose of this paper is to develop new knowledge in experimental characterization of contaminants in engine lubricants, using surface plasmon resonance (SPR) sensing that can be applicable for on‐line condition monitoring of lubricant quality and engine component performance.

Design/methodology/approach

The effect of change in optical properties (e.g. transparency, absorption, and refractive index) of engine lubricants caused by the introduction of contaminants, such as gasoline, coolant, and water, on the surface plasmon resonance characteristics is analyzed experimentally. In SPR measurement, variations in both the refractive index and absorption cause changes in the SPR curve, which is the dependence of reflectivity vs incidence angle. The SPR characteristics (e.g. refractivity) of engine lubricant contaminated by gasoline, water and coolant at different concentration are measured as a function of resonance angle and analyzed with respect to different concentration (1%‐10%) of contaminants. Also, pattern recognition analysis between fresh and used engine lubricants is performed, to show applicability of Bayesian classification methodology for on‐line monitoring and predicting engine lubricant condition.

Findings

It was shown experimentally that attenuation of surface plasmons due to introduction of contaminants to the engine lubricant leads to a noticeable change in resonance angle and reflectivity minimum of the SPR curve due to an increase in the dielectric permittivity. In addition, the changes in the SPR characteristics were observed between fresh and used engine lubricant, causing resonance angle and reflectivity minimum of the SPR curve to shift.

Practical implications

The knowledge generated in this study lays the informational basis to further develop an on‐line system for engine lubricant condition monitoring using miniaturized SPR sensors fully suitable for on board applications.

Originality/value

SPR characterization is originally applied for analysis of optical properties of engine lubricants caused by the introduction of contaminants, such as gasoline, coolant, and water.

Article
Publication date: 1 December 2017

Nur Alia Sheh Omar and Yap Wing Fen

This paper aims to review the potential application of surface plasmon resonance (SPR) in diagnosis of dengue virus (DENV-2) E-protein and the development of SPR to become…

Abstract

Purpose

This paper aims to review the potential application of surface plasmon resonance (SPR) in diagnosis of dengue virus (DENV-2) E-protein and the development of SPR to become an alternative DENV sensor.

Design/methodology/approach

In this review, the existing standard laboratory techniques to diagnosis of DENV are discussed, together with their drawbacks. To overcome these drawbacks, SPR has been aimed to be a valuable optical biosensor for identification of antibodies to the DENV antigen. The review also includes the future studies on three-dimensional poly(amidoamine) (PAMAM) dendrimer-surface-assembled monolayer (SAM)-Au multilayer thin films, which are envisaged to have high potential sensitive and selective detection ability toward target E-proteins.

Findings

Application of SPR in diagnosis of DENV emerged over recent years. A wide range of immobilized biorecognition molecules have been developed to combine with SPR as an effective sensor. The detection limit, sensitivity and selectivity of SPR sensing in DENV have been enhanced from time to time, until the present.

Originality/value

The main purpose of this review is to provide authors with up-to-date and useful information on sensing DENV using SPR and to introduce a novel three-dimensional PAMAM-SAM-Au multilayer thin films for future research on SPR sensing applications.

Details

Sensor Review, vol. 38 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Abstract

Details

Energy Economics
Type: Book
ISBN: 978-1-83867-294-2

Article
Publication date: 16 June 2021

Kofi Mintah Oware, Arunima Kambikkanon Valacherry and Thathaiah Mallikarjunappa

The purpose of this study is to focus on examining whether third-party assurance (TPA) and mandatory corporate social responsibility reporting (MCSR) matter in the…

Abstract

Purpose

The purpose of this study is to focus on examining whether third-party assurance (TPA) and mandatory corporate social responsibility reporting (MCSR) matter in the association between philanthropic giving (PHG) and listed firms’ financial performance.

Design/methodology/approach

Using the Indian stock market as a testing ground, the study used interactive regression and panel regression to analyse 80 sustainability-reporting firms with 800 firm-year observations between 2010 and 2019.

Findings

The first findings show a positive association between PHG and financial performance (return on assets, ROA and stock price returns, SPR). Also, the study shows that the interactive variable of MCSR and PHG has a mixed association with financial performance. The second findings show a positive and statistically significant association between TPA and SPR. Also, the interactive effect of TPA and PHG has a negative association with return on equity (ROE) and a positive association with SPR. The third findings show a negative association between MCSR and financial performance (ROA and ROE) and a positive association with SPR. However, when a firm combines MCSR and TPA, the outcome is a negative association with ROE. The fourth findings show that MCSR has a positive association with TPA. The study control for any form of heteroscedasticity, serial correlation and endogeneity effects.

Practical implications

Managers, if given a choice, must opt for TPA over MCSR because the βcoefficient is higher in TPA than MCSR in PHG-financial performance nexus.

Originality/value

The study addresses the information asymmetry problem from the application of TPA and MCSR, which is new to an emerging economy context.

Details

Social Responsibility Journal, vol. 18 no. 5
Type: Research Article
ISSN: 1747-1117

Keywords

Article
Publication date: 3 August 2021

Rui Wang, Chunlan Liu, Yong Wei and Yudong Su

This paper aims to study the sensitivity enhancement effect of the gold nanorod on fiber surface plasmon resonance (SPR) sensor. It proposes modeling the sensing effects…

108

Abstract

Purpose

This paper aims to study the sensitivity enhancement effect of the gold nanorod on fiber surface plasmon resonance (SPR) sensor. It proposes modeling the sensing effects of fiber SPR sensor decorated with metal nanoparticles. By using simulation and experiment, the sensitivity enhancement effect of the gold nanorod was studied and demonstrated.

Design/methodology/approach

The paper opted for an exploratory study using simulation approach of finite-difference time-domain. Specifically, the effect of ratios and aspect ratios of gold nanorod on sensing performance are investigated theoretically. Based on the mathematical models, the validation experiments by using the gold nanorod with the aspect ratios of 5.1 were done to verify the sensitivity enhancement effect of the gold nanorod.

Findings

In conclusion, it is evident that with the increases of the aspect ratios, the sensing sensitivity of the refractive index increases first, then gradually stabilizes or decreases. After parameter optimization, the ratios and aspect ratios of gold nanorod are chosen to be 8 nm and 12.5, respectively, which makes the optimal refractive index sensitivity of 4465.53 nm/RIU be realized. In addition, the validation experiments by using the gold nanorod with the aspect ratios of 5.1 verify the sensitivity enhancement effect of the gold nanorods.

Originality/value

This paper proposes and demonstrates a new method for the sensitivity enhancement of fiber SPR sensor. After parameter optimization, the maximum sensitivity of 4465.53 nm/RIU was achieved by using 8 nm gold nanorods with the aspect ratios of 12.5. To verify the sensitivity enhancement of the gold nanorods, the authors also did the validation experiments. The testing results indicated that after the decoration of the gold nanorods, the sensitivity of the sensing probe increases from 2190.57 nm/RIU to 2693.24 nm/RIU, which demonstrates the sensitivity enhancement effect of the gold nanorods.

Details

Sensor Review, vol. 41 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

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