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Electrocatalytic Reduction of Oxygen at Perovskite (BSCF)-MWCNT Composite Electrodes

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Materials Sciences and Applications 2014年第4期5卷 199-211页

作者： Farhanini Yusoff norita Mohamed azizan aziz Sulaiman ab Ghani Pusat Pengajian Kejuruteraan Bahan & Sumber Mineral Universiti Sains Malaysia Georgetown Malaysia Pusat Pengajian Sains Kimia Universiti Sains Malaysia Georgetown Malaysia

A composite paste electrode based on Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF)—initially synthesized by solgel method—and multiwall carbon nanotube (MWCNT) as a cathode in fuel cells is developed. The composite pastes are prepared by the direct mixing of BSCF:MWCNT at 90:10, 80:20 and 70:30 (% w/W). These electrodes are then characterized by the x-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen adsorption-desorption isotherm, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The XRD and SEM confirm the inclusion and the uniform dispersal of the MWCNT within BSCF, respectively. The nitrogen adsorption isotherm study shows that the porosity of the composite paste electrode has been improved by two-fold from the BSCF electrode. The EIS and CV demonstrate that the higher ratios of MWCNT in the composites are critical in improving the electronic conductivity as well as the kinetics. It is also noticeable that the electrode has increased the catalysis of oxygen in 0.1 M KOH (pH 12.0). Cyclic voltammetric studies on the oxygen reduction reaction (ORR) suggest that the incorporation of MWCNT is vital in improving the electrode (cathode) properties of a fuel cell.

关键词： Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) Catalysis Composites Multiwall Carbon Nanotube (MWCNT) Oxygen Reduction Reaction

Stimulation of Multiple Leader Formation in Some Genotypes of Acacia mangiumand Acacia auriculiformiswith 6-Benzylaminopurine (BAP)

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Open Journal of Forestry 2015年第7期5卷 637-650页

作者： Ahmed Mohamed Adam Eldoma Sures Kumar Muniandi nor Aini ab Shukor College of Forestry and Range Sciences Sudan University of Science and Technology Khartoum Sudan Department of Forest Management Faculty of Forestry Universiti Putra Malaysia Serdang Malaysia Institute of Tropical Forestry and Forest Product Universiti Putra Malaysia Serdang Malaysia

Acacia mangium Willd. and Acacia auriculiformis A. Cunn. ex. Benth. are two of the fast-growing tropical acacias which have received priority for genetic assessment and improvement. They were therefore proposed for timber production in a short rotation in Malaysia but were impeded by the multiple leaders (ML) formation which limited their value as sawn timber. This work attempts to investigate the causes of ML formation in four genotypes of A. mangium and A. auriculiformis as related to apical dominance, nutrition and plant growth hormones and their correlations. The effects of 6-benzylaminopurine and decapitation on ML formation of these genotypes were also investigated. 6-benzylaminopurine (BAP) as a foliar spray and also decapitation did not stimulate ML formation. However, they significantly increased the number of branches and reduced all other growth traits including height. However, basal diameter was not affected by decapitation. The effects of BAP increased consistently with increasing level of application. BAP at 1500 mg·Lǃ resulted in mortality of A. mangium provenances while A. auriculiformis provenances survived and grew normally. Some of the BAP treated plants of both species developed juvenile pinnate leaves. Decapitation of the apical bud resulted in the activation of the lateral bud immediately below the point of decapitation.

关键词： Cytokinin Multiple Leader Provenance Genotypes Apical Control Stem Form

Activity and Stability of Rare Earth-Based Hydride Alloys as Catalysts of Hydrogen absorption-Oxidation Reactions

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Journal of Rare Earths 2004年第6期22卷 871-874页

作者：应桃开高学平胡伟康 noréus Dag College of Biology and Chemistry Zhejiang Normal University Jinhua 321004China Institute of New Energy Material Chemistry Nankai University Tianjin 300071China Department of Structural Chemistry Arrhenius Laboratory Stockholm University S-106 91 Stockholm Sweden

Rare earth-based ab(5)-type hydrogen storage alloys as catalysts of hydrogen-diffusion electrodes for hydrogen absorption and oxidation reactions in alkaline fuel cells were investigated. It is demonstrated that the metahydride hydrogen-diffusion electrodes could be charged by hydrogen gas and electrochemically discharged, at the same time to retain a stable oxidation potential for a long period. The catalytic activities and stability are almost comparable with a Pt catalyst on the active carbon. Further improvement of performances is expected via reduction of catalyst size into nanometers.

关键词： inorganic chemistry electrocatalyst alkaline fuel cell hydrogen oxidation rare earths

Leg or antenna injury in Cataglyphis ants impairs survival but does not hinder searching for food

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Current Zoology 2022年第4期68卷 441-450页

作者： Tomer Gilad Arik Dorfman aziz Subach Inon Scharf School of Zoology Faculty of Life SciencesTel Aviv University69978 Tel AvivIsrael

Injury is common in nature resulting,for example,from fighting,partial predation,or the wear of body *** is costly,expressed in impaired performance,failure in competition,and a shorter life span.A survey of the literature revealed the frequent occurrence of injury in ants and its various *** examined whether leg or antenna injury impacts food-discovery time and reduces the likelihood of reaching food in workers of the desert ant Cataglyphis *** examined the search-related consequences of injury in groups of either 4 or 8 workers searching for food in a short arena,a long arena,and a *** conducted a small field survey to evaluate the prevalence of injury in the studied ***,we compared the survival rates of injured versus uninjured workers in the *** was common in the field,with almost 9%of the workers collected out of the nest,found to be *** workers survived shorter than uninjured ones and there was a positive link between injury severity and ***,we could not detect an effect of injury on any of the searching-related response variables,neither in the arenas nor in the mazes *** suggest that workers that survive such injury are only moderately affected by it.

关键词： binary-tree maze desert ants foraging injury movement review survival

Female reproductive system of Amaranthusas the target for Agrobacterium-mediated transformation

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Advances in Bioscience and Biotechnology 2013年第2期4卷 188-192页

作者： Umaiyal Munusamy Siti nor Akmar abdullah Maheran abd aziz Huzwah Khazaai Department of Agriculture Technology Faculty of Agriculture Universiti Putra Malaysia Serdang Malaysia Department of Biomedical Science Faculty of Medicine and Health Sciences Universiti Putra Malaysia Serdang Malaysia

Agrobacterium-mediated transformation through floral dip and rapid selection process after transgenic event had become a preference as it will overcome the difficulties faced in tissue culturing procedures and lengthy time for screening transformed progenies. Therefore, in this study, three constructs, p5b5 (14,289 bp), p5d9 (15,330 bp) and p5f7 (15,380 bp) in pDRB6b vector which has hygromycin as a selectable marker gene were introduced individually into Agrobacterium tumefaciens strain (AGL1). The cell suspension was applied to Amaranthus inflorescence by drop-by-drop technique and was left to produce seeds (T1). The T1 seeds were germinated and grown to produce seedlings under non-sterile condition. Hygromycin selection on seedling cotyledon leaves results in identification of 12 putative transformants, three from p5b5, four from p5d9 and five from p5f7. All positive putative transformants that were selected at the first stage through hygromycin spraying showed positive result in leaf disk hygromycin assay and in a construct specific polymerase chain reaction-based assay. A ~750 bp amplified hygromycin gene was further verified through sequencing. Our results suggest that Amaranthus inflorescences were able to be transformed and the transformed progenies could be verified through a combination of simple and rapid methods .

关键词： Agrobacterium-Mediated Transformation Amaranthus Direct PCR Female Reproductive System Floral-Dip Hygromycin

Morphological and molecular characterization of fungus isolated from tropical bed bugs in northern Peninsular Malaysia, Cimex hemipterus(Hemiptera: Cimicidae)

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Asian Pacific Journal of Tropical Biomedicine 2015年第9期5卷 684-690页

作者： abdul Hafiz ab Majid Zulaikha Zahran abd Hafis abd Rahim nor Azliza Ismail Wardah abdul Rahman Kartiekasari Syahidda Mohammad Zubairi Hamady Dieng Tomomitsu Satho Household and Structural Urban Entomology Laboratory School of Biological Sciences Universiti Sains Malaysia Plant Pathology Laboratory School of Biological Sciences Universiti Sains Malaysia Institute of Biodiversity and Environmental Conservation Universiti Malaysia Sarawak Department of Microbiology Faculty of Pharmaceutical Sciences Fukuoka University

Objective:To investigate some morphological and molecular characteristics of fungal parasites isolated from wild tropical bed bug, Cimex ***: A series of culture methods were used to obtain fungal isolates from i eld-collected bed bugs. Characteristics of the isolates such as colony appearance, mycelial texture and pigmentation were studied to explore their morphology. Isolates were also subjected to a PCRbased genotyping ***: There were noticeable dif erences in morphological characteristics among the four isolates. Conidial areas of one isolate were dark green, whereas those of the remaining colonies were olive-green, black or dark brown. Conidia of the dark green isolate were globose, while those of olive-green, black and dark brown isolates were globose to subglobose, globose to spherical and globose to subglobose/i nely roughened, respectively. These morphological specii cities and the molecular analyses showed that the fungal internal transcribed spacer ribosomal region and β-tubulin gene sequences of the isolates shared clade with Trichoderma and Aspergillus ***: Overall, the new discovery of common pathogens in agricultural i eld developed in live bed bugs storage tank may initiate the use of biological agents in later years.

关键词： Cimex hemipterus Aspergillus Trichoderma β-tubulin Internal transcribed spacer Morphological characteristics

Effects of Site Burning on Multiple Leader Formation and Growth Performance of Selected AcaciaGenotypes

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American Journal of Plant Sciences 2015年第5期6卷 777-784页

作者： Ahmed Mohamed Adam Eldoma Sures M. Kumar nor Aini ab Shukor College of Forestry and Range Sciences Sudan University of Science and Technology Khartoum Sudan Department of Forest Management Faculty of Forestry Universiti Putra Malaysia Serdang Selangor Malaysia Institute of Tropical Forestry and Forest Product Universiti Putra Malaysia Serdang Selangor Malaysia

Loss of apical dominance, resulting in seedlings with more than one leader, generally referred to as multiple leaders (ML), has been a major problem in forest tree plantation in the tropics. A study to examine the effects of site preparation by burning on growth performance and multiple leaders (ML) formation, and its variation in eight-genotypes of Acacia mangium and Acacia auriculiformis was conducted. The design used for this field trial is a randomized complete block design with four replications at two sites (burnt and unburned) and eight genotypes (four from each species), and the effects were monitored for 24 months. There were significant differences at P A. mangium provenances were more responsive to burning than A. auriculiformis, whereas at the unburned site, the variation between them was not significant. Based on the above variation, it can be concluded that burning causes ML formation and can affect the growth of these selected Acacia genotypes.

关键词： Acacias Genotype Multiple Leaders Growth Performance Site Preparation

Selection of Plus Tree Based on Growth Performance and Fiber Morphology Characteristics as Improved Sources for Propagation of Eucalyptus camaldulensis

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American Journal of Plant Sciences 2014年第9期5卷 1329-1335页

作者： Nozad Ali Qader nor Aini ab Shukor Adlin Sabrina Muhd. Roseley Department of Forest Management Faculty of Forestry Universiti Putra Malaysia Serdang Malaysia Department of Forest Production Faculty of Forestry Universiti Putra Malaysia Serdang Malaysia

One of the most successful techniques in planting trees is tree improvement in which trees with high qualities are selected for mass plantation. This study seeks to identify good properties of Eucalyptus camaldulensis through selective phases. Sixty Eucalyptus camaldulensis trees (30 ten-year-old and 30 five-year-old) were randomly selected through stratified sampling from two plantation sites in Kurdistan region, north of Iraq. The trees were examined for fiber morphology and quality parameters such as height, number of branches, diameter and straightness. In the first phase of property selection, sixteen trees with high rank in growth properties and fiber morphology were selected. In the final phase of selection, the selected trees were re-examined according to the number of properties and fiber morphology features and seven trees with the highest number of good parameters were chosen. The 7 selected trees had higher qualities in growth characteristics and fiber morphology compared with the other trees in the sample. This article reports on a selection method for E. camaldulensis trees through tree improvement techniques. The results of the study indicates that high genotype qualities were identified among both 5- and 10-year-old E. camaldulensis trees as the final selection consisted of three 5-year-old trees and four 10-year-old trees.

关键词： Eucalyptus camaldulensis Tree Improvement Growth Characteristics Fiber Morphology

Toxic effects of Litsea elliptica Blume essential oil on red blood cells of Sprague-Dawley rats

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第11期10卷 813-819页

作者： Izatus Shima TAIB Siti Balkis BUDIN Seri Maseran SITI nor AIN Jamaludin MOHAMED Santhana Raj LOUIS Srijit DAS Sulaiman SALLEHUDIN nor Fadilah RAJab Othman HIDAYATULFATHI Department of Biomedical Sciences Faculty of Allied Health SciencesUniversiti Kebangsaan MalaysiaJalan Raja Muda Abdul Aziz50300 Kuala LumpurMalaysia Unit of Electron Microscope Institute for Medical ResearchJalan Pahang50588 Kuala LumpurMalaysia Department of Anatomy Universiti Kebangsaan MalaysiaJalan Raja Muda Abdul Aziz50300 Kuala LumpurMalaysia

Litsea elliptica Blume leaves have been traditionally used as medicinal herbs because of its antimutagenicity,chemopreventative and insecticidal properties. In this study,the toxic effects of L. elliptica essential oil against Sprague-Dawley rat’s red blood cells (RBCs) were evaluated. L. elliptica essential oil was given by oral gavage 5 times per week for 3 treated groups in the doses of 125,250,and 500 mg/(kg body weight),respectively,and the control group received distilled water. Full blood count,RBC osmotic fragility,RBC morphological changes,and RBC membrane lipid were analyzed 28 d after the treatment. Although L. elliptica essential oil administration had significantly different effects on hemoglobin (Hb),mean cell hemoglobin concentration (MCHC),mean cell volume (MCV),and mean cell hemoglobin (MCH) in the experimental groups as compared to the control group (Pnormal range. L. elliptica induced morphological changes of RBC into the form of echinocyte. The percentage of echinocyte increased significantly among the treated groups in a dose-response manner (P0.05). It is concluded that structural changes in the RBC membrane due to L. elliptica essential oil administration did not cause severe membrane damage.

关键词： Litsea elliptica Toxicity Red blood cells Morphology Cell membrane Echinocyte