期刊文献+
共找到4,211篇文章
< 1 2 211 >
每页显示 20 50 100
Scanning Electron Microscopy(SEM) Observations of Antennal Sensilla of Chrysopa pallens Rambur(Neuroptera:Chrysopidae)
1
作者 Wang Juan Chen Hongyin +3 位作者 Wang Mengqing Liu Chenxi Zhang Haiping Zhang Lisheng 《Plant Diseases and Pests》 CAS 2017年第2期1-4,19,共5页
[Objectives]The paper was to provide background information for ongoing research on relationship between smell and behavior of the green lacewing Chrysopa pallens( Rambur)( Neuroptera: Chrysopidae). [Methods]The ... [Objectives]The paper was to provide background information for ongoing research on relationship between smell and behavior of the green lacewing Chrysopa pallens( Rambur)( Neuroptera: Chrysopidae). [Methods]The submicroscopic structure of antennal sensilla of C. pallens was examined using scanning electron microscopy. [Results]Antennae of female and male C. pallens were linear in shape and( 1. 52 ± 0. 08) and( 1. 58 ± 0. 23) cm in length,respectively. The scape and pedicel were composed of single sub-segment,while the flagellum consisted of 116 sub-segments,on which most sensilla distributed. The flagella of female and male antennae were( 1. 44 ± 0. 04) and( 1. 47 ± 0. 13) cm in length,respectively. Nine morphological sensilla types were recorded in both sexes,including four types of highly abundant and widely distributed sensilla trichodea( ST Ⅰ,ST Ⅱ,ST Ⅲ and ST Ⅳ),three types of sensilla basiconica( SB Ⅰ,SB Ⅱ,and SB Ⅲ),and one of each type of sensilla chaetica and B9 hm bristles. Although the shape,structure,numbers,and distribution of antennae of females and males were basically similar,major differences were recorded between the sexes in the length of some sensilla types. Both the ST Ⅲ and SB Ⅰ in female adults were significantly longer than that in male ones. Notably,SB Ⅱ was found only in female. [Conclusions]The paper laid a foundation for revealing the relationship between smell and behavior,playing a crucial role in promoting the important biological control effect of C. pallens in farmland ecological system. 展开更多
关键词 Chrysopa pallens ANTENNA SENSILLA ULTRASTRUCTURE scanning electron microscopy
下载PDF
Scanning Electron Microscopy (SEM) of the Bug Eye and Sand Coral
2
作者 Sayid Ali Sayid Aliyu Dadan-Garba +1 位作者 Daniel Elaigwu Enenche Barnabas Achakpa Ikyo 《Microscopy Research》 2020年第1期1-7,共7页
We present a Scanning Electron Microscopy (SEM) technique for the characterisation of biological and non-biological samples at nano-scale level. Scanning Electron Microscopy has been around for a long while especially... We present a Scanning Electron Microscopy (SEM) technique for the characterisation of biological and non-biological samples at nano-scale level. Scanning Electron Microscopy has been around for a long while especially in material science laboratories in developed countries. The SEM has enabled scientist to have a better understanding of microstructure by providing unsurpassed optical magnifications of samples. In this introductory paper, we introduce the techniques of using SEM to capture highly magnified microstructure of a fly found on an African soybean (Glycine max) seed. We are able to estimate the number of lenses in each eye and zoom into features that could describe its life characteristics. Hexagonal lenses are estimated to have sizes ranging from 14 um to 19 um. This paper also presents a finding of a sea coral “pie like structure” on a single grain of sand used for water filtration. 展开更多
关键词 Bug Eye Sand Coral scanning electron microscopy
下载PDF
TiO<sub>2</sub>Nanoparticles Induced Genotoxicity in Cultured Cells Using Atmospheric Scanning Electron Microscopy (ASEM)
3
作者 Shigeru Sato Takashi Takaki +1 位作者 Hidetoshi Nishiyama Tokuya Omi 《Journal of Cosmetics, Dermatological Sciences and Applications》 2013年第1期121-123,共3页
Nano-sized titanium oxide nanoparticles (TiO2 NPs) are widely used as a dye in food and cosmetics. TiO2 NPs are known to induce DNA damage when incorporated into cells. However, no bioassay is currently available to e... Nano-sized titanium oxide nanoparticles (TiO2 NPs) are widely used as a dye in food and cosmetics. TiO2 NPs are known to induce DNA damage when incorporated into cells. However, no bioassay is currently available to easily determine the cell incorporation of TiO2 NPs or related DNA damage, and to date, few studies have examined the different degrees of incorporation into cells according to the size of the TiO2 NPs particles and the presence or absence of cell specificity regarding DNA damage. This present study was therefore designed to examine COS7 cells that had incorporated TiO2 NPs using atmospheric scanning electron microscopy (ASEM). The results indicated that absorption of TiO2 NPs into cells and nuclear abnormalities had occurred. ASEM is a rapid and simple technique that enables the observation of samples immediately after fixation with glutaraldehyde and staining with phosphotungstic acid, and this method was suggested to be useful in screening for DNA damage. 展开更多
关键词 COS7 Cells TiO2 ATMOSPHERIC scanning electron microscopy (Asem) NANOPARTICLE
下载PDF
Adverse Effects of Permanent Waving and Hair Relaxation—Assessment by Scanning Electron Microscopy (SEM)
4
作者 Tokuya Omi Seiji Kawana 《Journal of Cosmetics, Dermatological Sciences and Applications》 2013年第3期45-48,共4页
Permanent waving is very popular in Japan. Polypeptide chains (main chains) form the principal components of hair, and they are lined up longitudinally. Hair relaxation is also called straight permanent waving, and th... Permanent waving is very popular in Japan. Polypeptide chains (main chains) form the principal components of hair, and they are lined up longitudinally. Hair relaxation is also called straight permanent waving, and there are methods that change curly or wavy hair into straight hair. Hair damage as a result of winding, combing, and using high-temperature hairdressing irons is also often seen. By using scanning electron micrographs (SEM) we showed broken hairs and hair damage caused by permanent wave solutions. The hair damage is obvious when comparisons are made with the condition of the hair surface, condition of the cuticle, etc. Hair swelling by permanent wave solutions, manipulations such as winding, etc., inadequate rinsing with water, procedures on injured hair at the outset, etc., are considered possible reasons for any of these types of injury. 展开更多
关键词 PERMANENT Waving HAIR RELAXATION scanning electron MICROGRAPHS (sem) HAIR Damage
下载PDF
50 years of scanning electron microscopy of bone——a comprehensive overview of the important discoveries made and insights gained into bone material properties in health,disease,and taphonomy 被引量:2
5
作者 Furqan A.Shah Krisztina Ruscsák Anders Palmquist 《Bone Research》 SCIE CAS CSCD 2019年第2期123-137,共15页
Bone is an architecturally complex system that constantly undergoes structural and functional optimisation through renewal and repair.The scanning electron microscope (SEM) is among the most frequently used instrument... Bone is an architecturally complex system that constantly undergoes structural and functional optimisation through renewal and repair.The scanning electron microscope (SEM) is among the most frequently used instruments for examining bone.It offers the key advantage of very high spatial resolution coupled with a large depth of field and wide field of view.Interactions between incident electrons and atoms on the sample surface generate backscattered electrons,secondary electrons,and various other signals including X-rays that relay compositional and topographical information.Through selective removal or preservation of specific tissue components (organic,inorganic,cellular,vascular),their individual contribution(s) to the overall functional competence can be elucidated.With few restrictions on sample geometry and a variety of applicable sample-processing routes,a given sample may be conveniently adapted for multiple analytical methods.While a conventional SEM operates at high vacuum conditions that demand clean,dry,and electrically conductive samples,non-conductive materials (e.g.,bone) can be imaged without significant modification from the natural state using an environmental scanning electron microscope.This review highlights important insights gained into bone microstructure and pathophysiology,bone response to implanted biomaterials,elemental analysis,SEM in paleoarchaeology,3D imaging using focused ion beam techniques,correlative microscopy and in situ experiments.The capacity to image seamlessly across multiple length scales within the meso-micro-nano-continuum,the SEM lends itself to many unique and diverse applications,which attest to the versatility and user-friendly nature of this instrument for studying bone.Significant technological developments are anticipated for analysing bone using the SEM. 展开更多
关键词 scanning electron microscopy COMPREHENSIVE OVERVIEW important discoveries
下载PDF
Bacterial entombment by intratubular mineralization following orthograde mineral trioxide aggregate obturation: a scanning electron microscopy study 被引量:5
6
作者 Jun Sang Yoo Seok-Woo Chang +8 位作者 So Ram Oh Hiran Perinpanayagam Sang-Min Lim Yeon-Jee Yoo Yeo-Rok Oh Sang-Bin Woo Seung-Hyun Han Qiang Zhu Kee-Yeon Kum 《International Journal of Oral Science》 SCIE CAS CSCD 2014年第4期227-232,共6页
The time domain entombment of bacteria by intratubular mineralization following orthograde canal obturation with mineral trioxide aggregate(MTA) was studied by scanning electron microscopy(SEM). Single-rooted huma... The time domain entombment of bacteria by intratubular mineralization following orthograde canal obturation with mineral trioxide aggregate(MTA) was studied by scanning electron microscopy(SEM). Single-rooted human premolars(n560) were instrumented to an apical size #50/0.06 using ProF ile and treated as follows: Group 1(n510) was filled with phosphate buffered saline(PBS); Group 2(n510) was incubated with Enterococcus faecalis for 3 weeks, and then filled with PBS; Group 3(n520) was obturated orthograde with a paste of OrthoM TA(BioM TA, Seoul, Korea) and PBS; and Group 4(n520) was incubated with E. faecalis for 3 weeks and then obturated with OrthoM TA–PBS paste. Following their treatments, the coronal openings were sealed with PBS-soaked cotton and intermediate restorative material(IRM), and the roots were then stored in PBS for 1, 2, 4, 8 or 16 weeks. After each incubation period, the roots were split and their dentin/MTA interfaces examined in both longitudinal and horizontal directions by SEM. There appeared to be an increase in intratubular mineralization over time in the OrthoM TA-filled roots(Groups 3 and 4). Furthermore, there was a gradual entombment of bacteria within the dentinal tubules in the E. faecalis inoculated MTA-filled roots(Group 4). Therefore, the orthograde obturation of root canals with OrthoM TA mixed with PBS may create a favorable environment for bacterial entombment by intratubular mineralization. 展开更多
关键词 bacterial entombment intratubular mineralization orthograde canal obturation scanning electron microscopy tag-like structure
下载PDF
Comparison of scanning electron microscopy findings regarding biofilm colonization with microbiological results in nasolacrimal stents for external, endoscopic and transcanalicular dacryocystorhinostomy 被引量:1
7
作者 Melike Balikoglu-Yilmaz Tolga Yilmaz +4 位作者 Sule Cetinel Umit Taskin Ayse Banu Esen Muhittin Taskapili Timur Kose 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第3期534-540,共7页
AIM:To compare bacterial biofilm colonization in lacrimal stents following external dacryocystorhinostomy(EX-DCR),endoscopic dacryocystorhinostomy(EN-DCR),and transcanalicular dacryocystorhinostomy(TC-DCR)with multidi... AIM:To compare bacterial biofilm colonization in lacrimal stents following external dacryocystorhinostomy(EX-DCR),endoscopic dacryocystorhinostomy(EN-DCR),and transcanalicular dacryocystorhinostomy(TC-DCR)with multidiode laser.METHODS:This prospective study included 30consecutive patients with nasolacrimal duct obstruction who underwent EXT-,EN-,or TC-DCR.Thirty removed lacrimal stent fragments and conjunctival samples were cultured.The lacrimal stent biofilms were examined by scanning electron microscopy(SEM).RESULTS:Eleven(36.7%)of the 30 lacrimal stent cultures were positive for aerobic bacteria(most commonly Staphylococcus epidermidis and Pseudomonas aeruginosa).However anaerobic bacteria and fungi were not identified in the lacrimal stent cultures.Twenty-seven(90%)patients had biofilmpositive lacrimal stents.The conjunctival culture positivity after the DCR,biofilm positivity on stents,the grade of biofilm colonization,and the presence of mucus and coccoid and rod-shaped organisms did not significantly differ between any of the groups(P】0.05).However,a significant difference was found when the SEM results were compared to the results of the lacrimal stent and conjunctival cultures(P【0.001).CONCLUSION:Type of dacryocystorhinostomy(DCR)surgery did not affect the biofilm colonization of the lacrimal stents.SEM also appears to be more precise than microbiological culture for evaluating the presence of biofilms on lacrimal stents. 展开更多
关键词 biofilms nasolacrimal duct obstruction EPIPHORA DACRYOCYSTITIS scanning electron microscopy
下载PDF
Scanning transmission electron microscopy: A review of high angle annular dark field and annular bright field imaging and applications in lithium-ion batteries 被引量:1
8
作者 仝毓昕 张庆华 谷林 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第6期23-34,共12页
Scanning transmission electron microscopy(STEM) has been shown as powerful tools for material characterization,especially after the appearance of aberration-corrector which greatly enhances the resolution of STEM. H... Scanning transmission electron microscopy(STEM) has been shown as powerful tools for material characterization,especially after the appearance of aberration-corrector which greatly enhances the resolution of STEM. High angle annular dark field(HAADF) and annular bright field(ABF) imaging of the aberration-corrected STEM are widely used due to their high-resolution capabilities and easily interpretable image contrasts. However, HAADF mode of the STEM is still limited in detecting light elements due to the weak electron-scattering power. ABF mode of the STEM could detect light and heavy elements simultaneously, providing unprecedented opportunities for probing unknown structures of materials. Atomiclevel structure investigation of materials has been achieved by means of these imaging modes, which is invaluable in many fields for either improving properties of materials or developing new materials. This paper aims to provide a introduction of HAADF and ABF imaging techniques and reviews their applications in characterization of cathode materials, study of electrochemical reaction mechanisms, and exploring the effective design of lithium-ion batteries(LIBs). The future prospects of the STEM are also discussed. 展开更多
关键词 scanning transmission electron microscopy high angle annular dark field annular bright field lithium-ion batteries
下载PDF
Functional Microvascular Anatomy of the Horse Eye: A Scanning Electron Microscopic Study of Corrosion Casts 被引量:1
9
作者 Hiroyoshi Ninomiya Tomo Inomata 《Open Journal of Veterinary Medicine》 2014年第5期91-101,共11页
Objective: This study presents the microvasculature of the horse iris, ciliary process, retina, and choroid and discusses the functional significance of the vasculature. Procedure: Seven horses were used for this stud... Objective: This study presents the microvasculature of the horse iris, ciliary process, retina, and choroid and discusses the functional significance of the vasculature. Procedure: Seven horses were used for this study. The ocular vascular system was injected with methylmethacrylate resin via the carotid artery, and the vascular corrosion casts were observed using a scanning electron microscope. Results: The iridial vessels showed a wavy course. The ciliary process was supplied by 2 arterial routes: the iridial and ciliary arterial circles. The subjects displayed a paurangiotic retina with retinal vessels extending only a short distance around the disc. The retinal arterioles and venules ran in closely related pairs, and the capillaries formed hairpin loops. No central retinal artery was seen in the equine eyes examined. The choriocapillaris in the avascular retina was arranged in honeycomb hexagon lobules and formed a more densely packed network than that in the vascular retina. There were 2 distinct venous drainage systems in the horse choroid: the vortex veins and the posterior ciliary veins. The vortex vein ampulla was flattened and showed a slit-like lumen at the merge site with the ophthalmic vein. The vortex veins demonstrated a marked constriction before leaving the eye. Discussion: The 2 choroidal drainage systems may compensate each other in event of occlusion. The ampulla and the constriction in the vortex veins may act as a valve regulating the blood flow to keep the eye at an optimum size and the intraocular pressure within the normal physiological range. 展开更多
关键词 CORROSION CAST Eye HORSE MICROVASCULATURE scanning electron microscopy
下载PDF
Scanning electron microscopy coupled with energydispersive X-ray spectrometry for quick detection of sulfuroxidizing bacteria in environmental water samples 被引量:1
10
作者 孙承君 蒋凤华 +5 位作者 高伟 李小云 于延珍 尹晓斐 王勇 丁海兵 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第1期185-191,共7页
Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not mee... Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not meet the requirements of analysis for time-sensitive samples and/or complicated environmental samples. Since energy-dispersive X-ray spectrometry(EDS) can be used to simultaneously detect multiple elements in a sample, including sulfur, with minimal sample treatment, this technology was applied to detect sulfur-oxidizing bacteria using their high sulfur content within the cell. This article describes the application of scanning electron microscopy imaging coupled with EDS mapping for quick detection of sulfur oxidizers in contaminated environmental water samples, with minimal sample handling. Scanning electron microscopy imaging revealed the existence of dense granules within the bacterial cells, while EDS identified large amounts of sulfur within them. EDS mapping localized the sulfur to these granules. Subsequent 16S rRNA gene sequencing showed that the bacteria detected in our samples belonged to the genus Chromatium, which are sulfur oxidizers. Thus, EDS mapping made it possible to identify sulfur oxidizers in environmental samples based on localized sulfur within their cells, within a short time(within 24 h of sampling). This technique has wide ranging applications for detection of sulfur bacteria in environmental water samples. 展开更多
关键词 扫描电子显微镜 硫氧化细菌 快速检测 能量色散 环境水样 X射线光谱法 环境样品分析 基因测序技术
下载PDF
IDENTIFICATION OF MARINE AEROSOL COMPONENT BY COMBINED NAA AND SCANNING ELECTRON MICROSCOPY WITH X—RAY ANALYSIS
11
作者 杨绍晋 章一鸣 《Nuclear Science and Techniques》 SCIE CAS CSCD 1992年第3期205-209,共5页
The concentrations of 30 elements in aerosol particles collected in western Pacific ocean have been determined by INAA. The crustal element concentrations decrease with increasing distance from land over the remote ar... The concentrations of 30 elements in aerosol particles collected in western Pacific ocean have been determined by INAA. The crustal element concentrations decrease with increasing distance from land over the remote area close to Asia land and fluctuate around its average value over the remote ocean area. The volatile elements exhibite average atmospheric concentrations that are higher than those expected from the flux of seasalt or the continental dust. In order to identify marine aerosol component originating from the continent or ocean, the aerosol particles are examined by scanning electron microscopy combined with energy dispersive X-ray spectroscopy. Particle phase structure shows that the crustal aerosol particles are not present internal mixtures with seasalt aerosol, and it also proves the long-range transport of crustal elements from continent to ocean. 展开更多
关键词 AEROSOL scanning electron microscopy INAA EDS
下载PDF
Scanning Electron Acoustic Microscopy of GaInAsSb by Metalorganic Chemical Vapor Deposition
12
作者 李树玮 金亿鑫 +3 位作者 周天明 张宝林 宁永强 蒋红 《Rare Metals》 SCIE EI CAS CSCD 1996年第2期101-105,共5页
Scanning electron acoustic microscopy (SEAM) is a new technique for imasing and characterization ofthermal, elastic and pyroelectric property variations on a microscale resolution. The signal generation mechanisms and... Scanning electron acoustic microscopy (SEAM) is a new technique for imasing and characterization ofthermal, elastic and pyroelectric property variations on a microscale resolution. The signal generation mechanisms and the application of scanning electron acoustic microscopy in GalnAsSb alloy grown by MOCVD wereinvestigated. Defects below the surface of GalnAsSb alloy were found by SEAM images and cathodelumi-nescence. The results show that electronacoustic imaging has its own features over secondary electron imag-ing. 展开更多
关键词 scanning electron acoustic microscopy electron-acoustic imaging GAINASSB MOCVD
下载PDF
Ultrastructural Analysis of the Ontogenetic Development of Shoot Induced from Embryonic Axes of Costa Rican Bean Varieties (<i>Phaseolus vulgaris</i>L.) under <i>in Vitro</i>Conditions by Scanning Electronic Microscopy
13
作者 Marisol Jiménez Andrés Gatica +1 位作者 Ethel Sánchez Marta Valdez 《American Journal of Plant Sciences》 2012年第4期489-494,共6页
Common bean (Phaseolus vulgaris L.) is an economic important crop and one of the major grain legumes for human consumption in Latin America, Africa and Asia. A morphological study of shoot induced from embryonic axes ... Common bean (Phaseolus vulgaris L.) is an economic important crop and one of the major grain legumes for human consumption in Latin America, Africa and Asia. A morphological study of shoot induced from embryonic axes development in four Costa Rican bean varieties (Brunca, Huetar, Guaymi and Bribri) cultivated on MS media with or without 5 mg·L–1 de N6-benzylaminopurine (BAP) by scanning electron microscopy (SEM) was developed in the present work. Micrographs showed similarities and differences in the ultrastructure of the apical dome, epidermal surface, stomata and different types of trichomes in the varieties cultivated on organogenesis media. Genotypes with advantageous morphological characteristics for genetic transformation, in particular an exposed apical dome, were identified. This work will contribute to the optimization of the in vitro regeneration of four common bean varieties. 展开更多
关键词 PHASEOLUS vulgaris L BEAN In Vitro ORGANOGENESIS SHOOT scanning electron microscopy (sem)
下载PDF
Scanning Electron Microscopy Studies of YBa_2Cu_3O_(7-δ) Superconductors
14
作者 沙维 《Rare Metals》 SCIE EI CAS CSCD 1995年第4期245-248,共4页
Micrcostructures of bulk and thin film YBa_2Cu_3O_(7-δ) superconductors were studied by using scanning elec-tron microscopy (SEM). It was confirmed that viscous technique processed bulk YBa_2Cu_3O_(7-δ) has a homoge... Micrcostructures of bulk and thin film YBa_2Cu_3O_(7-δ) superconductors were studied by using scanning elec-tron microscopy (SEM). It was confirmed that viscous technique processed bulk YBa_2Cu_3O_(7-δ) has a homoge-neous microstructure across the pellet diameter. Concerning the thin film, it was found that 2  ̄H ̄+ ion implanta-tion with a dose of 1× 10 ̄(12)cm ̄(-2) at 50 keV does not cause microstructural change of the film at a micrometrelevel. Combined with previous studies by using high resolution transmission electron microscopy, it appearsthat the structural modification is at an atomic scale. 展开更多
关键词 SUPERCONDUCTORS Thin film Ion implantation scanning elec-tron microscopy(sem)
下载PDF
OBSERVATION AND ANALYSIS OF BLOOD CONTACTING SURFACE OF LEFT VENTRICULAR ASSIST DEVICE WITH SCANNING ELECTRON MICROSCOPY
15
作者 王惠荪 金永安 秦家楠 《Medical Bulletin of Shanghai Jiaotong University》 CAS 1989年第Z1期72-78,共7页
Thrombus formation in the artificial heart blood pump is a complex problem. The most important factor of thrombosis in the blood pump is the quality of blood contacting surface which is related to hemocompatibility of... Thrombus formation in the artificial heart blood pump is a complex problem. The most important factor of thrombosis in the blood pump is the quality of blood contacting surface which is related to hemocompatibility of materials and micromorphololgy or roughness of the surface. So it is necessary to understand the morphology of the surface inside of blood pump in order to develop and improve a good quality blood pump. The authors observed and analysed the inner surface of blood pumps (both preimplanted and postimplanted) with scanning electron microscopy (SEM) providing a means for evaluating the blood pumps and for developing good quality of blood pumps. It was observed that there were four kinds of surface defects on the inner surface of the blood pumps: air bubble domes, open bubble craters, contaminated dust and gel particles. Microcrakes had also been found on the diaphragm of the postimplanted pump. But in the newly improved blood pump that had been imlanted for 16 days, there were few defects on the blood contacting surface, and only a little fibrinous layer observed. It could be considered that the current design and modifications are reasonable. Since some problems associated with the surface defects and thrombosis still existed, further improvement in fabrication process and quality control procedures with SEM are under way. 展开更多
关键词 LEFT VENTRICULAR assist device scanning electron microscopy POLYURETHANE blood contacting SURFACE SURFACE defects THROMBOSIS
下载PDF
Study of the bones tissue reparation using nanostructured titanium implants with hydroxylapatite coatings by scanning electron microscopy
16
作者 Tatiana V. Pavlova Sergei Y. Zaitsev +1 位作者 Lubov A. Pavlova Dmitrij A. Kolesnikov 《Journal of Biomedical Science and Engineering》 2010年第8期807-810,共4页
A method of medical implants (biocomposites) preparation based on nanostructured titanium with nanocrystalline bioactive hydroxylapatite coatings is developed. The operative treatment using these implants improves the... A method of medical implants (biocomposites) preparation based on nanostructured titanium with nanocrystalline bioactive hydroxylapatite coatings is developed. The operative treatment using these implants improves the regeneration of bone tissue for rats, as compared to the “false-operated” animals. The morphological data at 7, 14, 21, 45 days are obtained by means of scanning electron microscopy and discussed. 展开更多
关键词 scanning electron microscopy IMPLANT Regeneration NANOSTRUCTURES Bone TISSUE
下载PDF
Visualization of atomic scale reaction dynamics of supported nanocatalysts during oxidation and ammonia synthesis using in-situ environmental(scanning) transmission electron microscopy
17
作者 Michael R.Ward Robert W.Mitchell +1 位作者 Edward D.Boyes Pratibha L.Gai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第6期281-290,I0007,共11页
Reaction dynamics in gases at operating temperatures at the atomic level are the basis of heterogeneous gas-solid catalyst reactions and are crucial to the catalyst function.Supported noble metal nanocatalysts such as... Reaction dynamics in gases at operating temperatures at the atomic level are the basis of heterogeneous gas-solid catalyst reactions and are crucial to the catalyst function.Supported noble metal nanocatalysts such as platinum are of interest in fuel cells and as diesel oxidation catalysts for pollution control,and practical ruthenium nanocatalysts are explored for ammonia synthesis.Graphite and graphitic carbons are of interest as supports for the nanocatalysts.Despite considerable literature on the catalytic processes on graphite and graphitic supports,reaction dynamics of the nanocatalysts on the supports in different reactive gas environments and operating temperatures at the single atom level are not well understood.Here we present real time in-situ observations and analyses of reaction dynamics of Pt in oxidation,and practical Ru nanocatalysts in ammonia synthesis,on graphite and related supports under controlled reaction environments using a novel in-situ environmental(scanning) transmission electron microscope with single atom resolution.By recording snapshots of the reaction dynamics,the behaviour of the catalysts is imaged.The images reveal single metal atoms,clusters of a few atoms on the graphitic supports and the support function.These all play key roles in the mobility,sintering and growth of the catalysts.The experimental findings provide new structural insights into atomic scale reaction dynamics,morphology and stability of the nanocatalysts. 展开更多
关键词 In-situ visualization Atomic scale reaction dynamics In-situ environmental scanning transmission electron microscopy with single atom resolution Supported nanoparticles Ammonia synthesis Oxidation reactions
下载PDF
Neutron Activation Analysis and Scanning Electron Microscopy of Phytoplankton in the Coastal Zone of Crimea (The Black Sea)
18
作者 P. S. Nekhoroshkov A. V. Kravtsova +1 位作者 M. V. Frontasyeva Yu. N. Tokarev 《American Journal of Analytical Chemistry》 2014年第5期323-334,共12页
The physiology and ecology of planktonic organisms are influenced by the concentration, chemical speciation and resulting bioavailability of some trace metals. The determination of the elemental structure of phytoplan... The physiology and ecology of planktonic organisms are influenced by the concentration, chemical speciation and resulting bioavailability of some trace metals. The determination of the elemental structure of phytoplankton is important for interpretation of physiological and functional states of coastal ecosystems. The present study is focused on the structure and elemental composition of the phytoplankton assemblages from the different coastal zones by instrumental neutron activation analysis (INAA), scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDS). For the first time these complementary techniques were simultaneously applied to study the Black Sea phytoplankton. The concentrations of 45 elements in the coastal phytoplankton communities used as bioindicator of inorganic contamination of the Black Sea coastal area near Sevastopol, Ukraine, were determined. Phytoplankton samples were collected by total tows of the plankton net with 35 μm pore size at 3 stations situated in polluted and relatively pristine water areas of the Sevastopol coastal zone during autumn period of the phytoplankton growth. The concentration of Mg, Al, Sc, Ti, V, Mn, As, Rb, Ba, Th and Fe, Cr increases exponentially from relatively pristine station to more polluted station and 10-times and 3-times greater, respectively, in the phytoplankton of the Sevastopol Bay. The rare-earth elements have relatively the same concentration values less than 1 μg/g and tend to accumulate in the phytoplankton from the polluted station in the Sevastopol Bay. The obtained results are in a good agreement with the elemental concentration data in the oceanic plankton, plankton communities from the White Sea and the Black Sea. Using energy-dispersive X-ray spectrometry the mineral particles of unknown origin and impurities of copper (0.42% by weight) in the phytoplankton at the polluted station and zinc (0.57% by weight) at the relatively pristine station were determined. 展开更多
关键词 Black Sea PHYTOPLANKTON scanning electron microscopy NEUTRON Activation Analysis Energy-Dispersive X-Ray SPECTROMETRY TRACE Elements
下载PDF
Nucleation and Growth of Thallium on Thin Film Mercury Electrode: Voltammetric, Scanning Electron Microscopy, Chronoamperometric and Electrochemical Impedance Studies
19
作者 Abdoulkadri Ayouba Mahamane Boubié Guel Paul-Louis Fabre 《American Journal of Analytical Chemistry》 CAS 2022年第11期415-430,共16页
Thallium is a heavy metal highly toxic to the biosphere. It can be determined by anodic stripping voltammetry after deposition on mercury film. The aim of this work is to study the conditions and mechanisms of deposit... Thallium is a heavy metal highly toxic to the biosphere. It can be determined by anodic stripping voltammetry after deposition on mercury film. The aim of this work is to study the conditions and mechanisms of deposition of Hg on glassy carbon electrode and Tl on Hg film by cyclic voltammetry, scanning electron microscopy, chronoamperometry and impedance techniques. The results showed a germination and growth of a 3D Hg phase on glassy carbon electrode. Similarly, the electrodeposition of Tl on Hg follows a 3D three-dimensional nucleation with diffusion controlled growth. The impedance measurements reveal an easier charge transfer on the Tl film. 展开更多
关键词 THALLIUM Mercury Film Cyclic Voltammetry scanning electron microscopy Impedance Measurements
下载PDF
MORPHOLOGICAL CHANGES OF RATS MUSCLES AT VARIOUS POSTMORTEM INTERVALS BY SCANNING ELECTRON MICROSCOPY
20
作者 廖志钢 易旭夫 +1 位作者 肖飞 彭雪梅 《Chinese Medical Sciences Journal》 CAS CSCD 1999年第4期255-258,共4页
INTRODUCTION  Themusclesofthebodybegintostiffenimmediatelyafterdeath,andthenceforththeygraduallyfixthejointsinastiffstatethatisknownasthecadavericrigidityorrigormortis.Rigormortisusuallytakesplace2~4hafterdeath;iti... INTRODUCTION  Themusclesofthebodybegintostiffenimmediatelyafterdeath,andthenceforththeygraduallyfixthejointsinastiffstatethatisknownasthecadavericrigidityorrigormortis.Rigormortisusuallytakesplace2~4hafterdeath;itincreasestoamaximumwithin12h,conti... 展开更多
关键词 关节僵直 死亡 形态学特点 扫描电子显微镜 动物实验 解剖
下载PDF
上一页 1 2 211 下一页 到第
使用帮助 返回顶部