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Wireless Sensor Security Issues on Data Link Layer:A Survey

Computers, Materials & Continua 2023年第5期75卷 4065-4084页

作者： Muhammad Zulkifl Hasan zurina mohd hanapi Muhammad Zunnurain Hussain Department of Communication Technology and Network Faculty of Computer Science and Information TechnologyUniversiti Putra MalaysiaSerdangSelangor43400Malaysia

A computer network can be defined as many computing devices connected via a communication medium like the internet.Computer network development has proposed how humans and devices communicate today.These networks have improved,facilitated,and made conventional forms of communication easier.However,it has also led to uptick in-network threats and assaults.In 2022,the global market for information technology is expected to reach$170.4 billion.However,in contrast,95%of cyber security threats globally are caused by human action.These networks may be utilized in several control systems,such as home-automation,chemical and physical assault detection,intrusion detection,and environmental monitoring.The proposed literature review presents a wide range of information on Wireless Social Networks(WSNs)and Internet of Things(IoT)frameworks.The aim is first to be aware of the existing issues(issues with traditional methods)and network attacks on WSN and IoT systems and how to defend them.The second is to review the novel work in the domain and find its limitations.The goal is to identify the area’s primary gray field or current research divide to enable others to address the range.Finally,we concluded that configuration.Message Rapid Spanning Tree Protocol(RSTP)messages have higher efficiency in network performance degradation than alternative Bridge Data Unit Protocol(BPDU)forms.The research divides our future research into solutions and newly developed techniques that can assist in completing the lacking component.In this research,we have selected articles from 2015 to 2021 to provide users with a comprehensive literature overview.

关键词： Wireless sensor networks(WSN) internet of things(IoT) industrial revolution 4.0(IR4.0) computer networks network security

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Ephemeroptera, Plecoptera, Trichoptera and Odonata(Insecta)Diversity and Distribution at Bukit Merah Resevoir River Feeders

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湿地科学 2016年第3期14卷 328-336页

作者： Suhaila Ab Hamid Nurhalida hanapi mohd Fakhrullah Salatssalam mohd Afendi Amir Shahruddin mohd Sah School of Biological Sciences Universiti Sains Malaysia

A study on the distribution of Ephemeroptera, Plecoptera, Trichoptera and Odonata in relation of environmental interruptions was done at three different rivers tributaries of Bukit Merah Reservoir, Perak namely Sungai Jelai, Sungai Ara, and Sungai Kurau from October 2013 to January 2014. A total of 1 942 individuals were collected during the 4month of the study. The number of Ephemeroptera was highest, which was found at Sungai Jelai and Sungai Kurau and dominated by Baetis from family Baetidae while at Sungai Kurau dominated by Trichoptera, Hydropsyche from family Hydropsychidae. Ecological and biological indices have been used to evaluate the diversity of Ephemeroptera, Plecoptera, Trichoptera and Odonata at each river. The highest Simpson's diversity index(D=0.893) and Pielou's evenness index(E=0.803) were recorded at Sungai Jelai while Sungai Ara had the highest value of Margalef's richness index(MgR I=5.698). The variance for the assemblages of Ephemeroptera, Plecoptera, Trichoptera and Odonata influenced by9 chemical and physical variables was really a satisfactory with total variance explained of 57.2%. The results of canonical correspondence analysis(CCA) model showed that two groups of insects taxa characterized by water parameters.The first group from the CCA analysis clustered the Ephemeroptera, Plecoptera, Trichoptera and Odonata genera showed that deterioration in dissolved oxygen concentration, pH and nitrate while the second group showed dependence on total dissolved solids(TDS), conductivity, total suspended solid(TSS) and velocity. The study showed that the distribution of Ephemeroptera, Plecoptera, Trichoptera and Odonata taxa was affected by the environmental interruptions such as human residential area, agricultural plantation and river embankment.

关键词： aquatic insect diversity distribution environmental interruptions

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Fabrication, characterization and response surface method optimization for quantum efficiency of fluorescent nitrogen-doped carbon dots obtained from carboxymethylcellulose of oil palms empty fruit bunch

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Chinese Journal of Chemical Engineering 2020年第2期28卷 584-592页

作者： Mohammed Abdullah Issa zurina Zainal Abidin Shafreeza Sobri Suraya Abdul-Rashid mohd Adzir Mahdi Nor Azowa Ibrahim Musa Y.Pudza Department of Chemical and Environmental Engineering Faculty of EngineeringUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Department of Computer&Communications Systems Engineering Faculty of EngineeringUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Department of Chemistry Faculty of ScienceUniversiti Putra Malaysia43400 SerdangSelangorMalaysia

Bio based nitrogen doped carbon dots(N-CDs)were obtained from empty fruit bunch carboxymethylcellulose and ethylenediamine(EDA)through one-pot hydrothermal carbonization route.The optimum as-formed NCDs were thoroughly characterized via Transmission electron microscopy(TEM),high-resolution TEM(HRTEM),Fourier transform infrared(FTIR),X-ray photoelectron spectra(XPS),UV–vis spectra(UV–Vis)and Fluorescence spectra(PL).Response surface methodology was statistically used to assess three independent variables that have major influence on the fluorescence quantum yield(QY),including temperature(230–270℃),time(2–6 h)and EDA mass(10%–23.3%).Based on analysis of variance(ANOVA)results,synthesis temperature was found to be the most influential factor on the QY,followed by time and EDA mass.Higher temperature,long synthesis time and high amount of EDA were satisfactorily enough for efficient carbonization conversion rate and obtaining highest QY of N-CDs.The obtained quadratic model(R^2=0.9991)shows a good correlation between the experimental data and predicted values.The optimum synthetic parameters are of 270℃temperature,6 h reaction time and 23.3%of EDA mass.The optimized as-made N-CDs exhibited blue photoluminescence with both excitation dependent/independent phenomena and high nitrogen content.The maximum emission intensity was 426 nm at a maximum excitation wavelength of 320 nm,with a QY of up to 22.9%.XPS and FTIR data confirmed the existence of polar containing groups,such as carbonyl,carboxyl,hydroxyl and amino groups over the surface of N-CDs whereas nitrogen species in the form of(pyridinic and graphitic-N)were introduced in the aromatic carbon domains,which imparts the hydrophilic and photostability of N-CDs.Taking into account the low-cost and sustainable production of N-CDs,this method considered a feasible route for converting low quality waste into value-added nanomaterials and utilizing for different functionalization processes and analytical applications.

关键词： Carbon dots Fluorescence Response surface methodology Optimization Nitrogen doped

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HypoGel负载Pd纳米催化剂制备与表征及温和条件下催化Suzuki反应(英文)

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催化学报 2015年第5期36卷 771-777页

作者： Kin Hong Liew Wan zurina Samad Norazzizi Nordin Poh Lee Loh Joon Ching Juan mohd Ambar Yarmo Badrul Hisham Yahaya Rahimi M. Yusop School of Chemical Sciences and Food Technology Faculty of Science and Technology Universiti Kebangsaan Malaysia 43600 UKM Bangi Selangor Darul Ehsan Malaysia Nanotechnolofly & Catalysis Research Centre (NANOCAT) University of Malaya 50603 Kuala Lumpur Malaysia Kluster Perubatan Regeneratif lnstitut Perubatan dan Pergigian Termaju Universiti Sains Malaysia 13200 Bertam Kepala Batas Pulau Pinan9 Malaysia

A new heterogeneous catalyst composed of Pd nanoparticles immobilized within a HypoG el resin has been prepared in the absence of any ligands using an extensive cross-linking method.This newly developed nanocatalyst was characterized by N_2 adsorption-desorption,X-ray diffraction(XRD),transmission electron microscopy(TEM),scanning electron microscopy(SEM),energy dispersive X-ray(EDX),Fourier transform infrared spectroscopy and inductively coupled plasma-mass spectrometer(ICP-MS)techniques.TEM and XRD results revealed that the Pd nanoparticles were well dispersed with diameters in the range of 4–12 nm,and an average size of about 8 nm.The cross-linked Pd catalyst demonstrated excellent catalytic activity towards the synthesis of a series of biaryl compounds by the reaction of various aryl halides(e.g.,bromides andiodides)with phenylboronic acid in the presence of tetrabutylammonium bromide.ICP-MS analysis indicated that there was only 0.25%weight loss of Pd(0.55±0.02 ppm)from the supported catalyst after the first cycle reaction.Furthermore,the catalyst showed excellent reusability(up to five uses)with consistently high levels of catalytic activity following its recovery by filtration.

关键词： Suzuki反应纳米催化剂温和条件制备 Pd 电感耦合等离子体质谱傅里叶变换红外光谱 ICP-MS

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