Synthesis of Ferrite Nanoparticle and Ferrite-Gold Heterostructures

The synthesis of uniform and monodispersed magnetic and optical nanocrystals has received much attention in recent years due to the size-dependent physicochemical properties. In this study, we have demonstrated a general approach for the synthesis of size-tunable ferrite and gold nanocrystals and their nanocomposite. The monodispersed magnetite nanocrystals were obtained by thermal decomposition of iron-oleate complex in a high boiling point solvent in presence of oleylamine and oleic acid. The size of magnetite nanocrystal can be tuned from 7 – 11nm by changing the amount of iron-oleate complex. The other key parameters such as temperature, amount of capping agents, types of solvent were also discussed. This synthetic procedure could also apply to synthesis other type of ferrite nanocrystals. When Mn-acetate was partially substituted for iron-oleate in a 1:2 ratio in the same reaction conditions as in the synthesis of Fe3O4, monodispersed MnFe2O4 nanocrytals with 14nm could be obtained. Except those magnetic nanocrystals, we also synthesized various sizes of monodispersed gold nanocrystals by reducing HAuCl4 in presence of t-butylamine-borane and oleylamine. By varying the reaction temperature, the particle size could be well-tuned from 2nm to 8nm with the characteristic surface plasmon absorption between 510 and 520 nm. For Fe3O4/Au composite, it was prepared via the decomposition of iron-oleate over the surface of the Au nanoparticles. The mean size of the Fe3O4/Au nanocomposite was ∼17 nm which shows a saturation magnetization of 46.92 emu/g and absorption peak at 512nm. These composites with both magnetic and optical properties would make them very promising in the fields of biomedine and environment.

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Batch Precipitation of Lead Iodide

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19941301 ◽

1994 ◽

Vol 59 (6) ◽

pp. 1301-1304

Author(s):

Jaroslav Nývlt ◽

Stanislav Žáček

Keyword(s):

Aqueous Solution ◽

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Crystal Size ◽

Lead Nitrate ◽

Lead Iodide ◽

Constant Rate ◽

Mean Size ◽

The Mean

Lead iodide was precipitated by a procedure in which an aqueous solution of potassium iodide at a concentration of 0.03, 0.10 or 0.20 mol l-1 was stirred while an aqueous solution of lead nitrate at one-half concentration was added at a constant rate. The mean size of the PbI2 crystals was determined by evaluating the particle size distribution, which was measured sedimentometrically. The dependence of the mean crystal size on the duration of the experiment exhibited a minimum for any of the concentrations applied. The reason for this is discussed.

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Effects of topical gel formulation of Ficus carica latex on cutaneous leishmaniasis induced by Leishmania major in BALB/c mice

BMC Research Notes ◽

10.1186/s13104-021-05614-8 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Ali Pouryousef ◽

Erfan Eslami ◽

Sepehr Shahriarirad ◽

Sina Zoghi ◽

Mehdi Emami ◽

...

Keyword(s):

Cutaneous Leishmaniasis ◽

Murine Model ◽

Leishmania Major ◽

Considerable Effect ◽

Ficus Carica ◽

Control Group ◽

Topical Gel ◽

The Third ◽

Mean Size ◽

The Mean

Abstract Objectives The current study aimed to evaluate the effects of Ficus carica latex on the treatment of cutaneous leishmaniasis (CL), induced by Leishmania major. A 5% topical gel with F. carica latex was prepared. BALB/c mice were infected by inoculation of amastigotes form of L. major. Thirty BALB/c mice were divided into five groups, where the first group was treated daily, the second group twice per day, and the third group every other day with the 5% topical gel, for 3 weeks. The sizes of the lesions were measured before and during the course of treatment. Results Although the mean size of lesions in the mice group treated with the 5% F. carica gel, especially in the group receiving daily treatment, was less than the mean size of the lesions in the control group, yet, the differences was not statistically significant (p > 0.05). The findings of the current study demonstrated that the 5% F. carica latex with a 3-week course of treatment had no considerable effect in recovery or control of CL induced by L. major in the murine model. Using higher concentration of F. carica latex and with longer treatment lengths may increase its efficacy in the treatment of CL.

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Mudrock Microstructure: A Technique for Distinguishing between Deep-Water Fine-Grained Sediments

Minerals ◽

10.3390/min11060653 ◽

2021 ◽

Vol 11 (6) ◽

pp. 653

Author(s):

Shereef Bankole ◽

Dorrik Stow ◽

Zeinab Smillie ◽

Jim Buckman ◽

Helen Lever

Keyword(s):

Grain Size ◽

Deep Water ◽

Sedimentary Facies ◽

X Ray Diffraction ◽

Weak Current ◽

Large Area ◽

Fine Grained ◽

Mean Size ◽

The Mean ◽

Water Facies

Distinguishing among deep-water sedimentary facies has been a difficult task. This is possibly due to the process continuum in deep water, in which sediments occur in complex associations. The lack of definite sedimentological features among the different facies between hemipelagites and contourites presented a great challenge. In this study, we present detailed mudrock characteristics of the three main deep-water facies based on sedimentological characteristics, laser diffraction granulometry, high-resolution, large area scanning electron microscopy (SEM), and the synchrotron X-ray diffraction technique. Our results show that the deep-water microstructure is mainly process controlled, and that the controlling factor on their grain size is much more complex than previously envisaged. Retarding current velocity, as well as the lower carrying capacity of the current, has an impact on the mean size and sorting for the contourite and turbidite facies, whereas hemipelagite grain size is impacted by the natural heterogeneity of the system caused by bioturbation. Based on the microfabric analysis, there is a disparate pattern observed among the sedimentary facies; turbidites are generally bedding parallel due to strong currents resulting in shear flow, contourites are random to semi-random as they are impacted by a weak current, while hemipelagites are random to oblique since they are impacted by bioturbation.

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Effect of the Mean Size of Fine Intermetallic Compounds on the Strength Property of Sintered Magnesium Alloy by Gas Atomization

Journal of the Japan Society of Powder and Powder Metallurgy ◽

10.2497/jjspm.63.657 ◽

2016 ◽

Vol 63 (7) ◽

pp. 657-662 ◽

Cited By ~ 2

Author(s):

Taku IWAOKA ◽

Masayuki AONUMA ◽

Mitsuru NAKAMURA

Keyword(s):

Magnesium Alloy ◽

Intermetallic Compounds ◽

Strength Property ◽

Gas Atomization ◽

Mean Size ◽

The Mean

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Late endoscopic evaluation of the ostium size after external dacryocystorhinostomy

European Journal of Ophthalmology ◽

10.1177/1120672120976044 ◽

2020 ◽

pp. 112067212097604

Author(s):

Reem R Al Huthail ◽

Yasser H Al-Faky

Keyword(s):

Chart Review ◽

Retrospective Chart Review ◽

Tertiary Hospital ◽

Nasal Endoscope ◽

Long Term Follow Up ◽

Mean Size ◽

External Dacryocystorhinostomy ◽

The Mean

Objective: To evaluate the effect of chronicity on the size of the ostium after external dacryocystorhinostomy (DCR) with intubation. Methods: Design: A retrospective chart review of patients who underwent external DCR with intubation over 10 years from January 2003 at a tertiary hospital. All patients were recruited and examined with rigid nasal endoscope. Results: A total number of 66 (85 eyes) patients were included. The mean age at the time of evaluation was 53.1 years with gender distribution of 54 females (81.8 %). The mean duration ±SD between the date of surgery and the date of evaluation was 33.2 ± 33.6 (6–118 months). Our study showed an overall anatomical and functional success of 98.8% and 95.3%, respectively. The mean size of the ostium (±SD) was 23.0 (±15.7) mm2 (ranging from 1 to 80.4 mm2). The size of the ostium was not a significant factor for failure ( p = 0.907). No statistically significant correlation was found between the long-term duration after surgery and the size of the ostium ( R: 0.025, p = 0.157). Conclusions: Nasal endoscopy after DCR is valuable in evaluating the ostium with no observed potential correlation between the long-term follow-up after surgery and the size of the ostium.

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Room Temperature Solvent-Free Synthesis of Monodisperse Magnetite Nanocrystals

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2006.135 ◽

2006 ◽

Vol 6 (3) ◽

pp. 852-856 ◽

Cited By ~ 25

Author(s):

X. R. Ye ◽

C. Daraio ◽

C. Wang ◽

J. B. Talbot ◽

S. Jin

Keyword(s):

Oleic Acid ◽

Solid State ◽

Large Scale ◽

Room Temperature ◽

Solvent Free ◽

Two Dimensional ◽

New Process ◽

High Boiling Point ◽

Magnetite Nanocrystals ◽

Solvent Free Synthesis

We have successfully demonstrated a facile, solvent-free synthesis of highly crystalline and monodisperse Fe3O4 nanocrystallites at ambient temperature avoiding any heating. Solid state reaction of inorganic Fe(II) and Fe(III) salts with NaOH was found to produce highly crystalline Fe3O4 nanoparticles. The reaction, if carried out in the presence of surfactant such as oleic acid–oleylamine adduct, generated monodisperse Fe3O4 nanocrystals extractable directly from the reaction mixture. The extracted nanoparticles were capable of forming self-assembled, two-dimensional and uniform periodic array. The new process utilizes inexpensive and nontoxic starting materials, and does not require a use of high boiling point and toxic solvents, thus is amenable to an environmentally desirable, large-scale synthesis of nanocrystals.

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Lead inclusions in aluminium

MRS Proceedings ◽

10.1557/proc-157-247 ◽

1989 ◽

Vol 157 ◽

Cited By ~ 6

Author(s):

E. Johnson ◽

L. Gråbaek ◽

J. Bohr ◽

A. Johansen ◽

L. Sarholt-Kristensen ◽

...

Keyword(s):

Hysteresis Loop ◽

Room Temperature ◽

Noble Gas ◽

Melting Transition ◽

X Ray Diffraction ◽

Free Surfaces ◽

The Matrix ◽

Mean Size ◽

The Mean ◽

Spontaneous Phase

ABSTRACTIon implantation at room temperature of lead into aluminium leads to spontaneous phase separation and formation of lead precipitates growing topotactically with the matrix. Unlike the highly pressurised (∼ 1–5 GPa) solid inclusions formed after noble gas implantations, the pressure in the lead precipitates is found to be less than 0.12 GPa.Recently we have observed the intriguing result that the lead inclusions in aluminium exhibit both superheating and supercooling [1]. In this paper we review and elaborate on these results. Small implantation-induced lead precipitates embedded in an aluminium matrix were studied by X-ray diffraction. The (111) Bragg peak originating from the lead crystals was followed during several temperature cycles, from room temperature to 678 K. The melting temperature for bulk lead is 601 K. In the first heating cycle we found a superheating of the lead precipitates of 67 K before melting occurred. During subsequent cooling a supercooling of 21 K below the solidification point of bulk lead was observed. In the subsequent heating cycles this hysteresis at the melting transition was reproducible. The full width of the hysteresis loop slowly decreased to 62 K, while the mean size of the inclusions gradually increased from 14.5 nm to 27 nm. The phenomena of superheating and supercooling are thus most pronounced for the small crystallites. The persistence of the hysteresis loop over successive heating cycles demonstrate that its cause is intrinsic in nature, and it is believed that the superheating originates from the lack of free surfaces of the lead inclusions.

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Mechanical ventilation-induced alterations of intracellular surfactant pool and blood–gas barrier in healthy and pre-injured lungs

Histochemistry and Cell Biology ◽

10.1007/s00418-020-01938-x ◽

2020 ◽

Author(s):

Jeanne-Marie Krischer ◽

Karolin Albert ◽

Alexander Pfaffenroth ◽

Elena Lopez-Rodriguez ◽

Clemens Ruppert ◽

...

Keyword(s):

Mechanical Ventilation ◽

Blood Gas ◽

Control Groups ◽

Gas Barrier ◽

Alveolar Epithelial ◽

Alveolar Surfactant ◽

Healthy Control ◽

Mean Size ◽

The Mean ◽

Injury Progression

AbstractMechanical ventilation triggers the manifestation of lung injury and pre-injured lungs are more susceptible. Ventilation-induced abnormalities of alveolar surfactant are involved in injury progression. The effects of mechanical ventilation on the surfactant system might be different in healthy compared to pre-injured lungs. In the present study, we investigated the effects of different positive end-expiratory pressure (PEEP) ventilations on the structure of the blood–gas barrier, the ultrastructure of alveolar epithelial type II (AE2) cells and the intracellular surfactant pool (= lamellar bodies, LB). Rats were randomized into bleomycin-pre-injured or healthy control groups. One day later, rats were either not ventilated, or ventilated with PEEP = 1 or 5 cmH2O and a tidal volume of 10 ml/kg bodyweight for 3 h. Left lungs were subjected to design-based stereology, right lungs to measurements of surfactant proteins (SP−) B and C expression. In pre-injured lungs without ventilation, the expression of SP-C was reduced by bleomycin; while, there were fewer and larger LB compared to healthy lungs. PEEP = 1 cmH2O ventilation of bleomycin-injured lungs was linked with the thickest blood–gas barrier due to increased septal interstitial volumes. In healthy lungs, increasing PEEP levels reduced mean AE2 cell size and volume of LB per AE2 cell; while in pre-injured lungs, volumes of AE2 cells and LB per cell remained stable across PEEPs. Instead, in pre-injured lungs, increasing PEEP levels increased the number and decreased the mean size of LB. In conclusion, mechanical ventilation-induced alterations in LB ultrastructure differ between healthy and pre-injured lungs. PEEP = 1 cmH2O but not PEEP = 5 cmH2O ventilation aggravated septal interstitial abnormalities after bleomycin challenge.

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