A comprehensive study on the synthesis and paramagnetic properties of PEG-coated Fe3O4 nanoparticles

2014 ◽  
Vol 303 ◽  
pp. 425-432 ◽  
Author(s):  
Jinghai Yang ◽  
Ping Zou ◽  
Lili Yang ◽  
Jian Cao ◽  
Yunfei Sun ◽  
...  
Keyword(s):  
Fe3o4 Nanoparticles ◽  
Paramagnetic Properties ◽  
Comprehensive Study

scholarly journals Preparation and Dielectric Properties of Polyaniline-Coated Magnetite Nanocomposites

2019 ◽  
Vol 32 (2) ◽  
pp. 385-390
Author(s):  
H.K. AbdulKadir
Keyword(s):  
Dielectric Properties ◽  
Fe3o4 Nanoparticles ◽  
Amorphous Structure ◽  
Structural Pattern ◽  
Bonding Analysis ◽  
Chemical Conjugation ◽  
Composites Materials ◽  
Magnetic Fe3o4 Nanoparticles ◽  
Conductive Properties ◽  
Paramagnetic Properties

The conductive polymers such as polyaniline (PANI) exhibit considerable electrical conductive properties. The coating of PANI with magnetic (Fe3O4) nanoparticles formed composites (PANI/Fe3O4) with required dielectric properties. The morphology result study of PANI/Fe3O4 by field emission scanning electron microscope (FESEM) indicate the presence of PANI with tubes like structure containing different wt % of Fe3O4 nanoparticles (5, 15, 25 wt %). The structural pattern investigated by XRD revealed the presence of Fe3O4 nanoparticles at 2θ = 35.58º, while the amorphous structure indicates the presence of PANI matrix. However, the chemical bonding analysis using FTIR shows chemical conjugation of bonds at 3336, 3300 and 3277 cm-1 due to presence of NH group in PANI and OH group in Fe3O4 nanoparticles, while presence of 504 and 526 cm-1 suggesting that Fe3O4 nanoparticles are present in the composites materials. The dielectric properties study by 4-point probe and VSM shows that PANI and PANI/Fe3O4 nanocomposites exhibit good electrical properties (1.55 to 1.35 S/cm) which are decreasing with increase of Fe3O4 nanoparticles, may be resulting due to insulating behaviour of the magnetic nanoparticles, while the magnetic properties of PANI/Fe3O4 nanocomposites indicate super paramagnetic properties with saturation magnetization of (59.4, 5.96, 11.94 and 15.43 emus/g).

scholarly journals A COMPREHENSIVE STUDY ON THE MICROSTRUCTURE AND OPTICAL PROPERTIES OF Fe3O4 NANOPARTICLES BY VARIATION OF TEMPERATURE AND NaOH CONCENTRATION

2019 ◽  
Vol 5 (1) ◽  
pp. 6-17
Author(s):  
I Putu Tedy Indrayana
Keyword(s):  
Optical Properties ◽  
Fe3o4 Nanoparticles ◽  
Synthesis Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microstructural Parameters ◽  
Crystal Density ◽  
Vis Spectroscopy ◽  
Crystallite Sizes ◽  
Comprehensive Study

This work was aimed at optimizing the microstructure and optical properties of Fe3O4 by variation of synthesis temperature and NaOH concentration. The nanoparticles have been synthesized from iron sand by using the coprecipitation method. The temperature was varied of 60oC, 80oC, and 100oC, while NaOH concentration was 3 molar, 5 molar, and 7 molars. The microstructural parameters were characterized by using X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) techniques. The optical properties were characterized by using Fourier Transform Infrared Spectroscopy (FTIR) and UV-Vis Spectroscopy, consecutively. The results showed that the crystallite size of Fe3O4 increase with an increase of synthesis temperature due to higher thermal energy driving the nucleation process. The crystallite sizes are in the range of 3.77 nm – 20.37 nm. Increasing NaOH concentration also affected the increase in crystallite sizes. On the other hand, an excess of NaOH concentration influences the formation of smaller crystallite sizes of Fe3O4 with smaller crystal density and larger microstrain. The existence of Fe2+-O and Fe3+-O vibration in FTIR spectra confirmed the formation of Fe3O4 nanoparticles. The direct and indirect optical gap energies of Fe3O4 were in the range of 3.15 eV – 3.39 eV and 2.39 eV – 2.91eV. The synthesis temperature and NaOH concentration have a significant role in controlling the properties of Fe3O4.  

Progress In The Practical Application Of Automated Image Analysis To Tem Negatives

1977 ◽  
Vol 35 ◽  
pp. 214-217
Author(s):  
F. A. Heckman ◽  
E. Redman ◽  
J.E. Connolly
Keyword(s):  
Image Analysis ◽  
Image Quality ◽  
Exposure Time ◽  
Image Contrast ◽  
Automated Image Analysis ◽  
Practical Application ◽  
Factors Affecting ◽  
High Image Quality ◽  
Qualitative Evidence ◽  
Comprehensive Study

In our initial publication on this subject1) we reported results demonstrating that contrast is the most important factor in producing the high image quality required for reliable image analysis. We also listed the factors which enhance contrast in order of the experimentally determined magnitude of their effect. The two most powerful factors affecting image contrast attainable with sheet film are beam intensity and KV. At that time we had only qualitative evidence for the ranking of enhancing factors. Later we carried out the densitometric measurements which led to the results outlined below.Meaningful evaluations of the cause-effect relationships among the considerable number of variables in preparing EM negatives depend on doing things in a systematic way, varying only one parameter at a time. Unless otherwise noted, we adhered to the following procedure evolved during our comprehensive study:Philips EM-300; 30μ objective aperature; magnification 7000- 12000X, exposure time 1 second, anti-contamination device operating.

Hexachlorobenzene toxicity in the monkey ovary: III. Ultrastructure induced by high (10 mg/kg) dose exposure

1991 ◽  
Vol 49 ◽  
pp. 130-131
Author(s):  
A. Singh ◽  
A. Dykeman ◽  
J. Jarrelf ◽  
D. C. Villeneuve
Keyword(s):  
Present Report ◽  
Reproductive Toxicity ◽  
Control Group ◽  
Primate Model ◽  
Human Follicular Fluid ◽  
Thin Sections ◽  
Cynomolgus Monkeys ◽  
Cacodylate Buffer ◽  
Induction Cycle ◽  
Comprehensive Study

Hexachlorobenzene (HCB), a persistent and mobile organochlorine pesticide, occurs in environment. HCB has been shown to be present in human follicular fluid. An objective of the present report, which is part of a comprehensive study on reproductive toxicity of HCB, was to determine the cytologic effects of the compound on ovarian follicles in a primate model.Materials and Methods. Eight Cynomolgus monkeys were housed under controlled conditions at Animal facility of Health and Welfare, Ottawa. Animals were orally administered gelatin capsules containing HCB mixed with glucose in daily dosages of 0.0 or 10 mg/kg b.w. for 90 days; the former was the control group. On the menstrual period following completion of dosing, the monkeys underwent an induction cycle of superovulation. At necropsy, one-half of an ovary from each animal was diced into ca. 2- to 3-mm cubed specimens that were fixed by immersion in 2.5% glutaraldehyde in 0.1 M cacodylate buffer (pH 7.3). Subsequent procedures followed to obtain thin sections that were examined in a Hitachi H-7000 electron microscope have been described earlier.

Comparison of Substructures Between Uniaxial and Biaxial Deformation in 1100-0 Aluminum

1981 ◽  
Vol 39 ◽  
pp. 52-53
Author(s):  
D. L. Rohr ◽  
S. S. Hecker
Keyword(s):  
Plastic Strain ◽  
Cell Walls ◽  
Room Temperature ◽  
Mechanical Response ◽  
Biaxial Tension ◽  
Initial Deformation ◽  
Uniaxial Deformation ◽  
Biaxial Deformation ◽  
Stress States ◽  
Comprehensive Study

As part of a comprehensive study of microstructural and mechanical response of metals to uniaxial and biaxial deformations, the development of substructure in 1100 A1 has been studied over a range of plastic strain for two stress states.Specimens of 1100 aluminum annealed at 350 C were tested in uniaxial (UT) and balanced biaxial tension (BBT) at room temperature to different strain levels. The biaxial specimens were produced by the in-plane punch stretching technique. Areas of known strain levels were prepared for TEM by lapping followed by jet electropolishing. All specimens were examined in a JEOL 200B run at 150 and 200 kV within 24 to 36 hours after testing.The development of the substructure with deformation is shown in Fig. 1 for both stress states. Initial deformation produces dislocation tangles, which form cell walls by 10% uniaxial deformation, and start to recover to form subgrains by 25%. The results of several hundred measurements of cell/subgrain sizes by a linear intercept technique are presented in Table I.

Microvasculature and structure of hemal lymph nodes in the wall of the rabbit bladder: a vascular corrosion casting and EM study

1995 ◽  
Vol 53 ◽  
pp. 1074-1075
Author(s):  
F.E. Hossler ◽  
M.I. McKamey ◽  
F.C. Monson
Keyword(s):  
Lymph Nodes ◽  
Light Microscopy ◽  
Corrosion Casting ◽  
Fixed Tissue ◽  
Infusion Pressure ◽  
India Ink ◽  
Cacodylate Buffer ◽  
Rabbit Bladder ◽  
Lateral Walls ◽  
Comprehensive Study

A comprehensive study of the microvasculature of the normal rabbit bladder, revealed unusual "capillary glomeruli" along the lateral walls. Here they are characterized as hemal lymph nodes using light microscopy, SEM, TEM, ink injection, and vascular casting.Bladders were perfused via a cannula placed in the abdominal aorta with either 2% glutaraldehyde in 0.1M cacodylate buffer (pH 7.4) for fixation, 10% India ink in 0.9% saline and 0.1M phosphate (pH 7.4) for vessel tracing, or resin (Mercoximethylmethacrylate: catalyst, 4:1:0.3; Ladd Research Industries) for vascular corrosion casting. Infusion pressure was 100mm Hg. Fixed tissue was sectioned from epon-araldyte resin, and stained with toluidine blue for light microscopy, and lead and uranium for TEM. Ink injected tissue was photographed directly from saline-filled bladders illuminated from below. Resin-filled tissue was macerated in 5% KOH and distilled water. Casts were critical point dried, sputter coated with goldpalladium, and examined by routine SEM at 10 KV.

Comprehensive Study of Blockchain Technology - Architecture, Consensus and Future Trends

2020 ◽  
pp. 319-325
Author(s):  
Shreya Joshi ◽  
Ms Bhavyaa ◽  
Suhani Gupta ◽  
Lalita Luthra
Keyword(s):  
Internet Of Things ◽  
Product Management ◽  
Future Trends ◽  
Deep Dive ◽  
Record Keeping ◽  
Blockchain Technology ◽  
Healthcare Product ◽  
Core Technology ◽  
Technical Challenges ◽  
Comprehensive Study

Blockchain is considered to be a disruptive core technology. Although many researchers have realized the importance of blockchain, but the research of it is still emerging. It is the record-keeping technology behind bitcoin and is one of the hottest and fastest growing skills in the IT sector today. It serves as an immutable ledger which allows transactions to take place in a decentralized man Blockchain-based applications are rising up, covering numerous fields including finance, healthcare, product management, Internet of Things (IoT), and many more. However, there are still some challenges of blockchain technology such as scalability and security problems which need to be overcome. This paper comprises of a comprehensive study of Blockchain technology. We have included here a deep dive into how blockchains work, its architecture, consensus and various applications. Furthermore, technical challenges are briefly listed.

The Influence Of The Led Luminaires Electrical Parameters On Their Correlated Colour Temperature During Operation Mode

2020 ◽  
pp. 89-96
Author(s):  
Sergei S. Kapitonov ◽  
Alexei S. Vinokurov ◽  
Sergei V. Prytkov ◽  
Sergei Yu. Grigorovich ◽  
Anastasia V. Kapitonova ◽  
...  
Keyword(s):  
Operation Mode ◽  
Light Sources ◽  
Electrical Parameters ◽  
Colour Temperature ◽  
Radiation Spectra ◽  
Service Period ◽  
Close Proximity ◽  
Definition Of ◽  
Comprehensive Study

The article describes the results of comprehensive study aiming at increase of quality of LED luminaires and definition of the nature of changes in their correlated colour temperature (CCT) in the course of operation. Dependences of CCT of LED luminaires with remote and close location of phosphor for 10 thousand hours of operation in different electric modes were obtained; the results of comparison between the initial and final radiation spectra of the luminaires are presented; using mathematical statistics methods, variation of luminaire CCT over the service period claimed by the manufacturer is forecast; the least favourable electric operation modes with the highest CCT variation observed are defined. The obtained results have confirmed availability of the problem of variation of CCT of LED luminaires during their operation. Possible way of its resolution is application of more qualitative and therefore expensive LEDs with close proximity of phosphor or LEDs with remote phosphor. The article may be interesting both for manufacturers and consumers of LED light sources and lighting devices using them.

Spaghetti Westerns at the Crossroads

2016 ◽  
Keyword(s):  
Ethnic Identities ◽  
Transnational Politics ◽  
Contextual Knowledge ◽  
Cultural Significance ◽  
Local Identities ◽  
Spaghetti Westerns ◽  
Comprehensive Study ◽  
National Local

This comprehensive study brings together leading international scholars in a variety of disciplines to both revisit the Spaghetti Western genre's cultural significance and consider its ongoing influence on international film industries. The book provides a range of innovative perspectives on this discrete and perennially popular topic. The book consists of four sections: Trans-Genre Roots; Ethnic Identities, Transnational Politics; Asian Crossovers; and Routes of Relocation, Transition, and Appropriation. Its rigorous historical, cultural, and political enquiry engages with current scholarly trends and balances specialized contextual knowledge with recognition of the instability of national/local identities. The book provides fresh interrogations of the myriad ways in which the Spaghetti Western has influenced contemporary filmmaking practice across national industries.

ЛАНДШАФТНАЯ ОРГАНИЗАЦИЯ БЕРЕГОВОЙ ГЕОСТРУКТУРЫ ОСТРОВА ШКОТА (ЗАЛИВ ПЕТРА ВЕЛИКОГО)

2019 ◽  
Author(s):  
K.S. Ganzei ◽  
V.V. Zharikov ◽  
N.F. Pshenichnikova ◽  
A.M. Lebedev ◽  
A.G. Kiselyova ◽  
...  
Keyword(s):  
Spatial Organization ◽  
Peter The Great Bay ◽  
Spatial Arrangement ◽  
Water Area ◽  
Marine Spatial Planning ◽  
Landscape Approach ◽  
Important Condition ◽  
Statistical Comparison ◽  
Peter The Great ◽  
Comprehensive Study

Важнейшим условием достижения устойчивого развития прибрежноморского природопользования в заливе Петра Великого системы является морское пространственное планирование. Основой для этого является информация о природных комплексах территории и акватории, полученная на основе ландшафтного подхода. Ключевым районом для изучения пространственной организации ландшафтов прибрежных геоструктур стала территория острова Шкота и его подводных склонов. Для наземных ландшафтов было описано 49 наблюдательных пунктов, 4 профиля были заложены для подводных ландшафтов описано 64 наблюдательных пункта, проложено 18 профилей. Выделено 22 вида ландшафтов, из них 16 наземных, 6 подводных. Берега острова сформированы преобладанием абразивноденудационного и абразивного типов. В результате всестороннего изучения показаны особенности пространственной организации воздушных и водных природных комплексов. Особенностью исследуемой территории является экспозиция дифференциации ландшафтов между юговосточной и северозападной частями острова, обусловленная муссонной природой климата. Результаты полевых и картографических работ послужили основой для выбора зон интенсивного, умеренного и ослабленного взаимодействия наземных и подводных ландшафтов. Пространственное расположение зон взаимодействия четко иллюстрируется значительными различиями экспозиции. Результаты статистического сравнения ландшафтов суши и мелководья, окружающего остров, на основе картометрических характеристик указывают на неоднородность геоструктуры острова, обусловленную, прежде всего, сочетанием ландшафтообразующих факторов. The most important condition for achieving sustainable development of coastalmarine environmental management in Peter the Great Bay is marine spatial planning. The basis for this is information about the natural complexes of the territory and water area, obtained based on the landscape approach. The main area for studying the spatial organization of landscapes of coastal geostructures was the territory of the island of Shkota and its underwater slopes. For terrestrial landscapes, 49 observation points were described, 4 profiles were laid 64 observation points were described for underwater landscapes, 18 profiles were laid. 22 species of landscapes have been identified, of which 16 are terrestrial, 6 are underwater. The shores of the island are formed by the predominance of abrasivedenudation and abrasive types. Because of a comprehensive study, features of the spatial organization of air and aquatic natural complexes are shown. A special feature of the study area is the exposure of the differentiation of landscapes between the southeastern and northwestern parts of the island, due to the monsoon nature of the climate. The results of field and cartographic works served as the basis for selecting areas of intense, moderate and weakened interaction of land and underwater landscapes. The spatial arrangement of the interaction zones is clearly illustrated by significant differences in exposure. The results of a statistical comparison of the land and shallow water landscapes surrounding the island, based on the cartometric characteristics, indicate the heterogeneity of the islands geostructure, primarily due to the combination of landscapeforming factors.

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