The morphology evolution, tunable down-conversion luminescence, and energy transfer of [CaY]F2 crystals doped with Li+/Ce3+/Tb3+

2020 ◽  
Vol 49 (43) ◽  
pp. 15433-15442
Author(s):  
Yini Mao ◽  
Zhiyi Wang ◽  
Rui Ye ◽  
Li Jiang ◽  
Shanshan Hu ◽  
...  

Octahedral [CaY]F2 crystals with an average particle size of 1 μm were synthesized via a mild one-step hydrothermal route without employing any surfactants.

2021 ◽  
Vol 18 (2) ◽  
pp. 63
Author(s):  
Kendri Wahyuningsih ◽  
Sri Yuliani ◽  
Wahyu Diyono ◽  
Hoerudin Hoerudin ◽  
Tatang Hidayat

Biosilica from rice husks has a potential that can be used as a reinforcing filler in the production of rubber finished goods displace mine silica. But it’s difficult to disperse homogenetically into a rubber finished goods, so it needs to modify the surface using a coupling agent sign. The capacity for the production of modified-biosilica would need to be at a great level to meet the needs of the rubber industry. The purpose of the research is to identify the characteristics of the modified-biosilica by silane TESPT (bis-(3-triethoxysilylpropyl) tetrasulfane) that resulted from increasing the weight of biosilica in the production process and the application as reinforcing filler on the rubber. Increasing of weight in the production process was done gradually on a scale of 0.5; 1; 2; and 5 kg of biosilica per process using a mixer-propeller. The technique on surface modifications was using a one-step modification (OSM) and two-step modification (TSM). Surface modification treatment using TESPT has increased the uniformity of the particle size distribution of the biosilica. Unmodified-biosilica has an average particle size of 717.1 nm (PDI 0.600), while modified-biosilica has an average particle size of 574.6 nm (PDI 0.585). Applications for reinforcing filler in the soles rubber industry are performed in PT Triangkasa Lestari Utama. Research indicates that increasing the weight of biosilica on the surface modifications did not significantly affect the density, lightness, crystallinity, and purity. The applications as reinforcing fillers have increased the quality of rubber finished goods compared with unmodified-biosilica. The best rubber finished goods quality approaching shoes-sol standards is a product that used modified-biosilica by OSM technique. This rubber finished goods has a tensile strength of 5.80 MPa, elongation at break of 425%, tear strength of 23.25% and abrasion resistance of 251.5 mm3 .


CrystEngComm ◽  
2020 ◽  
Vol 22 (29) ◽  
pp. 4862-4874
Author(s):  
Jie Xiong ◽  
Wei Wang ◽  
Yini Mao ◽  
Qingyuan Liu ◽  
Jun Yang ◽  
...  

BaLu2−xF8:xLn3+ crystals have been synthesized via a one-step hydrothermal route without any surfactants.


2011 ◽  
Vol 483 ◽  
pp. 301-304
Author(s):  
Jun Sheng Huang ◽  
Yu Ying Nie ◽  
Ying Chen

Copper-water nanofluids were obtained by a novel one-step KBH4 aqueous reduction of copper sulfate with complex compound EDTA-2Na and quaternary ammonium cationic dispersant C16H33(CH3)3NBr (CTAB). The average particle size of the nanofluids with 4g CTAB in 200ml solution was only 1.02nm measured by dynamic light scatter particle size analyser. The obtained powders centrifuged were pure copper mostly and contained a litter Cu2O which were influenced by the chemical reaction of complex compounds EDTA-2Na.


Author(s):  
Yu. M. Domnina ◽  
S. A. Kedik ◽  
V. V. Suslov ◽  
E. A. Shnyak ◽  
S. S. Kryukova

The work is dedicated to the production of polymer suspensions using ultrasonic dispergation in a flow mode. An apparatus was designed on the basis of a Russian flow ultrasonicator. The applicability of this apparatus for obtaining aqueous dispersions of polymeric micro- and nanoparticles by means of one-step emulsification followed by solvent extraction / evaporation was demonstrated. The influence of the process parameters on the characteristics of the obtained suspensions was studied. The particle size distribution and the average size of the resulting particles were evaluated by using Delsa Nano S, Beckman Coulter laser analyzer (USA). The dependence of the average diameter of the suspension particles on the stabilizer concentration and on the change of the phases feed rate was shown. When polyvinyl alcohol was used as a stabilizer in the concentration range 0.5-2%, the average particle size was 30-400 nm. The feed rates of the aqueous and organic phases affect the nature of the particle size distribution.


2011 ◽  
Vol 236-238 ◽  
pp. 1814-1817
Author(s):  
Hong Wang ◽  
Yan Jie ◽  
Hong Luo ◽  
Xue Feng

Monodisperse α-Fe2O3nanoparticles with average particle size of 110 nm were successfully prepared using olyvinylpyrrolidone (PVP) as surfactant via a novel hydrothermal route. The products were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM). The experiments results revealed that PVP and the concentration of NH4HCO3have played a crucial role in the formation of the monodisperse a-Fe2O3nanoparticles.


1970 ◽  
Vol 26 (1) ◽  
pp. 16 ◽  
Author(s):  
S Balasubramanian ◽  
Rajkumar Rajkumar ◽  
K K Singh

Experiment to identify ambient grinding conditions and energy consumed was conducted for fenugreek. Fenugreek seeds at three moisture content (5.1%, 11.5% and 17.3%, d.b.) were ground using a micro pulverizer hammer mill with different grinding screen openings (0.5, 1.0 and 1.5 mm) and feed rate (8, 16 and 24 kg h-1) at 3000 rpm. Physical properties of fenugreek seeds were also determined. Specific energy consumptions were found to decrease from 204.67 to 23.09 kJ kg-1 for increasing levels of feed rate and grinder screen openings. On the other hand specific energy consumption increased with increasing moisture content. The highest specific energy consumption was recorded for 17.3% moisture content and 8 kg h-1 feed rate with 0.5 mm screen opening. Average particle size decreased from 1.06 to 0.39 mm with increase of moisture content and grinder screen opening. It has been observed that the average particle size was minimum at 0.5 mm screen opening and 8 kg h-1 feed rate at lower moisture content. Bond’s work index and Kick’s constant were found to increase from 8.97 to 950.92 kWh kg-1 and 0.932 to 78.851 kWh kg-1 with the increase of moisture content, feed rate and grinder screen opening, respectively. Size reduction ratio and grinding effectiveness of fenugreek seed were found to decrease from 4.11 to 1.61 and 0.0118 to 0.0018 with the increase of moisture content, feed rate and grinder screen opening, respectively. The loose and compact bulk densities varied from 219.2 to 719.4 kg m-3 and 137.3 to 736.2 kg m-3, respectively.  


2020 ◽  
Vol 27 (22) ◽  
pp. 3623-3656 ◽  
Author(s):  
Bruno Fonseca-Santos ◽  
Patrícia Bento Silva ◽  
Roberta Balansin Rigon ◽  
Mariana Rillo Sato ◽  
Marlus Chorilli

Colloidal carriers diverge depending on their composition, ability to incorporate drugs and applicability, but the common feature is the small average particle size. Among the carriers with the potential nanostructured drug delivery application there are SLN and NLC. These nanostructured systems consist of complex lipids and highly purified mixtures of glycerides having varying particle size. Also, these systems have shown physical stability, protection capacity of unstable drugs, release control ability, excellent tolerability, possibility of vectorization, and no reported production problems related to large-scale. Several production procedures can be applied to achieve high association efficiency between the bioactive and the carrier, depending on the physicochemical properties of both, as well as on the production procedure applied. The whole set of unique advantages such as enhanced drug loading capacity, prevention of drug expulsion, leads to more flexibility for modulation of drug release and makes Lipid-based nanocarriers (LNCs) versatile delivery system for various routes of administration. The route of administration has a significant impact on the therapeutic outcome of a drug. Thus, the non-invasive routes, which were of minor importance as parts of drug delivery in the past, have assumed added importance drugs, proteins, peptides and biopharmaceuticals drug delivery and these include nasal, buccal, vaginal and transdermal routes. The objective of this paper is to present the state of the art concerning the application of the lipid nanocarriers designated for non-invasive routes of administration. In this manner, this review presents an innovative technological platform to develop nanostructured delivery systems with great versatility of application in non-invasive routes of administration and targeting drug release.


2020 ◽  
Vol 17 ◽  
Author(s):  
Mohammad Hossain Shariare ◽  
Tonmoy Kumar Mondal ◽  
Hani Alothaid ◽  
Md. Didaruzzaman Sohel ◽  
MD Wadud ◽  
...  

Aim: EPAS (evaporative precipitation into aqueous solution) was used in the current studies to prepare azithromycin nanosuspensions and investigate the physicochemical characteristics for the nanosuspension batches with the aim of enhancing the dissolution rate of the nanopreparation to improve bioavailability. Methods: EPAS method used in this study for preparing azithromycin nanosuspension was achieved through developing an in-house instrumentation method. Particle size distribution was measured using Zetasizer Nano S without sample dilution. Dissolved azithromycin nanosuspensions were also compared with raw azithromycin powder and commercially available products. Total drug content of nanosuspension batches were measured using an Ultra-Performance Liquid Chromatography (UPLC) system with Photodiode Array (PDA) detector while residual solvent was measured using gas chromatography (GC). Results: The average particle size of azithromycin nanosuspension was 447.2 nm and total drug content was measured to be 97.81% upon recovery. Dissolution study data showed significant increase in dissolution rate for nanosuspension batch when compared to raw azithromycin and commercial version (microsuspension). The residual solvent found for azithromycin nanosuspension is 0.000098023 mg/ mL or 98.023 ppb. Conclusion: EPAS was successfully used to prepare azithromycin nanoparticles that exhibited significantly enhanced dissolution rate. Further studies are required to scale up the process and determine long term stability of the nanoparticles.


Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1097
Author(s):  
Luran Zhang ◽  
Xinchen Du ◽  
Hongjie Lu ◽  
Dandan Gao ◽  
Huan Liu ◽  
...  

L10 ordered FePt and FePtCu nanoparticles (NPs) with a good dispersion were successfully fabricated by a simple, green, one-step solid-phase reduction method. Fe (acac)3, Pt (acac)2, and CuO as the precursors were dispersed in NaCl and annealed at different temperatures with an H2-containing atmosphere. As the annealing temperature increased, the chemical order parameter (S), average particle size (D), coercivity (Hc), and saturation magnetization (Ms) of FePt and FePtCu NPs increased and the size distribution range of the particles became wider. The ordered degree, D, Hc, and Ms of FePt NPs were greatly improved by adding 5% Cu. The highest S, D, Hc, and Ms were obtained when FePtCu NPs annealed at 750 °C, which were 0.91, 4.87 nm, 12,200 Oe, and 23.38 emu/g, respectively. The structure and magnetic properties of FePt and FePtCu NPs at different annealing temperatures were investigated and the formation mechanism of FePt and FePtCu NPs were discussed in detail.


Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2003
Author(s):  
Wei Xu ◽  
Jintao Wei ◽  
Zhengxiong Chen ◽  
Feng Wang ◽  
Jian Zhao

The type and fineness of a filler significantly affect the performance of an asphalt mixture. There is a lack of specific research on the effects of filler fineness and dust from aggregates on the properties of epoxy asphalt (EA) mixtures. The effects of aggregate dust and mineral powder on the properties of an EA mixture were evaluated. These filler were tested to determine their fineness, specific surface area and mineral composition. The effects of these fillers on the EA mastic sample and mixture were evaluated. The morphology of the EA mastic samples was analyzed using scanning electron microscopy (SEM). The effects of the fillers on the Marshall stability, tensile strength and fatigue performance of the EA mixture were evaluated. The dust from the aggregates exhibited an even particle size distribution, and its average particle size was approximately 20% of that of the mineral powder. The SEM microanalysis showed that the EA mastic sample containing relatively fine dust formed a tight and dense interfacial bonding structure with the aggregate. The EA mixture sample containing filler composed of dust from aggregate had a significantly higher strength and longer fatigue life than that of the EA sample containing filler composed of mineral powder.


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