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31.
Climate change is fast becoming the major environmental and energy concern worldwide. There is a major dilemma between the continued reliance on fossil fuel for our energy supply and the pressing need to address the problem of greenhouse gas (GHG) emissions from combustion process. This paper reviews the potential for carbon capture and storage (CCS) as a part of the climate change mitigation strategy for the Malaysian electricity sector using a technology assessment framework. The nation's historical trend of high reliance on fossil fuel for its electricity sector makes it a prime candidate for CCS adoption. The suitability and practicality of the technology was reviewed from a broad perspective with consideration of Malaysia-specific conditions. It is apparent from this assessment that CCS has the potential to play an important role in Malaysia's climate change mitigation strategy provided that key criteria are fulfilled. 相似文献
32.
Isolates of Lactobacillus delbrueckii subsp. lactis obtained from raw milk samples were compared for the ability to produce hydrogen peroxide (H2O2) at 5 degrees C. Nineteen out of 101 lactobacilli isolated were identified as L. delbrueckii subsp. lactis. The isolates of L. delbrueckii subsp. lactis from most raw milk samples produced more H2O2 than did isolates of other species of lactobacilli from the same samples. Seven isolates of L. delbrueckii subsp. lactis, which produced the highest levels of H2O2 at 5 degrees C were selected for comparison with a laboratory strain, L. delbrueckii subsp. lactis I. In 24 h, isolate RM2-5 produced 7.0 microg/10(9) cfu in buffer containing 5 mM sodium lactate and 4.4 microg/10(9) cfu in buffer containing 5 mM glucose. Three other isolates also produced more H2O2 on sodium lactate than on glucose. However, three remaining new isolates produced more H2O2 on glucose than on sodium lactate. All seven of the most active new isolates of L. delbrueckii subsp. lactis produced significantly higher concentrations of H2O2 than did L. delbrueckii subsp. lactis I in both solutions. Strain RM2-5 produced more H2O2 than did the other six most active newly isolated strains of L. delbrueckii subsp. lactis in this comparison. 相似文献
33.
A microscope slide acting as a passive waveguide was coated by three separate poly(vinyl alcohol) films that were doped with Coumarin 460, Disodium Fluorescein, and Rhodamine 640 perchlorate. On collinear pumping by a nitrogen laser, these dyes furnished primary red-green-blue laser emissions that were collected and waveguided by the microscope slide but exited from both ends. Frosting the waveguide exit introduced light scattering at the glass-air interface and spatially overlaid the red-green-blue laser emissions that emerged as a uniform white-light beam. 相似文献
34.
Zheng RT Ngo NQ Le Binh N Tjin SC 《Journal of the Optical Society of America. A, Optics, image science, and vision》2004,21(12):2399-2405
We present a new hybrid optimization method for the synthesis of fiber Bragg gratings (FBGs) with complex characteristics. The hybrid optimization method is a two-tier search that employs a global optimization algorithm [i.e., the tabu search (TS) algorithm] and a local optimization method (i.e., the quasi-Netwon method). First the TS global optimization algorithm is used to find a "promising" FBG structure that has a spectral response as close as possible to the targeted spectral response. Then the quasi-Newton local optimization method is applied to further optimize the FBG structure obtained from the TS algorithm to arrive at a targeted spectral response. A dynamic mechanism for weighting of different requirements of the spectral response is employed to enhance the optimization efficiency. To demonstrate the effectiveness of the method, the synthesis of three linear-phase optical filters based on FBGs with different grating lengths is described. 相似文献
35.
This study presents the effects of mixture fractions of nuclear fuels (mixture of fissile–fertile fuels and mixture of two different fertile fuels) and 6Li enrichment on the neutronic parameters (the tritium breeding ratio, TBR, the fission rate, FR, the energy multiplication ratio, M, the fissile breeding rate, FBR, the neutron leakage out of blanket, L, and the peak-to-average fission power density ratio, Γ) of a deuterium–tritium (D–T) fusion neutron-driven hybrid blanket. Three different fertile fuels (232Th, 238U and 244Cm), and one fissile fuel (235U) were selected as the nuclear fuel. Two different coolants (pressurized helium and natural lithium) were used for the nuclear heat transfer out of the fuel zone (FZ). The Boltzmann transport equation was solved numerically for obtaining the neutronic parameters with the help of the neutron transport code XSDRNPM/SCALE4.4a. In addition, these calculations were performed by also using the MCNP4B code. The sub-limits of the mixture fractions and 6Li enrichment were determined for the tritium self-sufficiency. The considered hybrid reactor can be operated in a self-sufficiency mode in the cases with the fuel mixtures mixed with a fraction of equal to or greater than these sub-limits. Furthermore, the numerical results show that the fissile fuel breeding and fission potentials of the blankets with the helium coolant are higher than with the lithium coolant. 相似文献
36.
The Singapore government is encouraging construction enterprises to venture abroad for exporting their services and become global players since the local construction pie is shrinking and the global market is growing. The Building and Construction Authority of Singapore has revamped the contractors registration system with the hope of bringing about merger and acquisition of companies for improving the local contractors’ standing in the global construction scene. To diversify into new markets in a new environment, which is very different from local environment, requires diversification vis-à-vis exporting strategy. This study examines the attitudes and views of contractors, operating in Singapore (excluding foreign contractors), on how the strategic move should be focused for diversification vis-à-vis exporting services. The aim of this study is to establish the survival skills necessary for Singapore’s construction small and medium sized enterprises (SMEs) to venture abroad. A postal questionnaire survey was conducted and the results show that local construction SMEs who have diversified have reaped the benefits derived from diversification into new markets abroad. The main conclusions are that construction SMEs have to export their services in order to survive and they can enhance their export capabilities by forming a consortium with the help of local government. 相似文献
37.
Chiung Ching Ho Hu Ng Wooi-Haw Tan Kok-Why Ng Hau-Lee Tong Timothy Tzen-Vun Yap Pei-Fen Chong C. Eswaran Junaidi Abdullah 《Pattern recognition letters》2013
This paper describes the baseline corpus of a new multimodal biometric database, the MMU GASPFA (Gait–Speech–Face) database. The corpus in GASPFA is acquired using commercial off the shelf (COTS) equipment including digital video cameras, digital voice recorder, digital camera, Kinect camera and accelerometer equipped smart phones. The corpus consists of frontal face images from the digital camera, speech utterances recorded using the digital voice recorder, gait videos with their associated data recorded using both the digital video cameras and Kinect camera simultaneously as well as accelerometer readings from the smart phones. A total of 82 participants had their biometric data recorded. MMU GASPFA is able to support both multimodal biometric authentication as well as gait action recognition. This paper describes the acquisition setup and protocols used in MMU GASPFA, as well as the content of the corpus. Baseline results from a subset of the participants are presented for validation purposes. 相似文献
38.
Hongyi Yang Jingying Charlotte Lim Yuchan Liu Xiaoying Qi Yee Ling Yap Vishwesh Dikshit 《Virtual and Physical Prototyping》2017,12(1):95-103
The purpose of this paper is to quantitatively evaluate the performance of a multi-material jetting 3D printer, ProJet 5500X, especially the capability for micro manufacturing. Unlike other single material 3D printer, ProJet 5500X uses photopolymers as the build material and wax as the support material. The building performance was evaluated by building a modified version of the standard benchmark model with a high-resolution printing mode. The dimensional error, forming quality and surface roughness of the printed parts have been measured and analysed using a microscope, a 3D coordinate measuring machine and a surface profilometer. Using wax as the support material, fine features as small as 0.25?mm, lateral features and sharper edges could all be properly built, despite the rough side surfaces observed in the printed part. Identical features (3?mm pins) were precisely built with an accuracy of 15?µm. The research provides first-hand detailed performance knowledge in the ProJet system for understanding the working principle and comparison with other 3D printing systems. 相似文献
39.
People involved in business are increasingly aware of the online social phenomenon and its potential as a marketing tool. Building upon the marketing, social psychology, and information system literature, this study empirically examines a set of functional determinants derived from the technology acceptance model and socio-psychological determinants drawn from the theory of reasoned action and social cognitive theory that may be responsible for the motivations of participants in online social networks. We propose a model by integrating functional, social, and psychological factors in predicting attitude and online social network usage. The survey outcomes from a cross-sectional study among 387 Facebook users in Malaysia support the hypothesised model. This study contributes by extending the cognitive learning theories in predicting online social networking usage. Particularly, this research presents a different perspective on online social networking by exploring the mediating effect of attitude and the moderating role of individual characteristics. This study demonstrates that desirable changes in the perception of functional benefits, self-efficacy, and need for cognition as well as perceptions of social pressure from significant others might lead to corresponding changes in attitude towards online social networking. Results of the study support the model efficacy and predictive ability of the proposed integrative model which may serve as a theoretical foundation for future researchers interested in examining other virtual community engagements such as blogging, online advertising, and online public relations activities. 相似文献
40.
Noraini Nordin Samikannu Kanagesan Nur Rizi Zamberi Swee Keong Yeap Nadiah Abu Subramani Tamilselvan Mansor Hashim Noorjahan Banu Alitheen 《IET nanobiotechnology / IET》2017,11(3):343
In this study, nanocrystalline magnesium zinc ferrite nanoparticles were successfully prepared by a simple sol–gel method using copper nitrate and ferric nitrate as raw materials. The calcined samples were characterised by differential thermal analysis/thermogravimetric analysis, Fourier transform infrared spectroscopy and X‐ray diffraction. Transmission electron microscopy revealed that the average particle size of the calcined sample was in a range of 17–41 nm with an average of 29 nm and has spherical size. A cytotoxicity test was performed on human breast cancer cells (MDA MB‐231) and (MCF‐7) at various concentrations starting from (0 µg/ml) to (800 µg/ml). The sample possessed a mild toxic effect toward MDA MB‐231 and MCF‐7 after being examined with MTT (3‐[4, 5‐dimethylthiazol‐2‐yl]‐2, 5 diphenyltetrazolium bromide) assay for up to 72 h of incubation. Higher reduction of cells viability was observed as the concentration of sample was increased in MDA MB‐231 cell line than in MCF‐7. Therefore, further cytotoxicity tests were performed on MDA MB‐231 cell line.Inspec keywords: sol‐gel processing, nanoparticles, nanofabrication, magnesium compounds, zinc compounds, toxicology, biological organs, cancer, cellular biophysics, nanomedicine, calcination, differential thermal analysis, Fourier transform infrared spectra, X‐ray diffraction, transmission electron microscopy, particle size, organic compoundsOther keywords: sol‐gel method, cytotoxic effects, breast cancer cell line, MDA MB‐231 in vitro, nanocrystalline magnesium zinc ferrite nanoparticles, copper nitrate, ferric nitrate, raw materials, calcined samples, differential thermal analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, average particle size, cytotoxicity testing, human breast cancer cells, mild toxic effect, 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5 diphenyltetrazolium bromide) assay, cell viability, MCF‐7, MDA MB‐231 cell line, size 17 nm to 41 nm 相似文献