Preparation of Silica Nanotubes with Cobalt Complex Nanofibers as Templates

2007 ◽  
Vol 121-123 ◽  
pp. 343-346
Author(s):  
Li Rong Ren ◽  
Lin Guo ◽  
Michael Wark

Co-silica nanotubes were prepared with nanofibers of [Co(NH3)6](HCO3)(CO3)·2H2O as templates. The yield and morphology of Co-silica nanotubes were influenced by the pH value of the ammonia solution, the concentration of the Co salt solution as well as the rate of ethanol addition. The optimized sample contains 100% nanotubes with 150 – 300 nm in diameter and up to 30 -m in length.

2018 ◽  
Vol 24 (8) ◽  
pp. 5523-5526 ◽  
Author(s):  
B Shalini ◽  
A. Ruban Kumar ◽  
A. Mary Saral

Hydroxyapatite (HAp) is the most widely accepted biomaterial for the repair and reconstruction of bone tissue defects. The current study is based on HAp was synthesized using sol–gel method. The drug was loaded in presence and absence of gelatin with pure HAp. Precursors like calcium nitrate tetrahydrate and diammonium hydrogen orthophosphate were used and ammonia solution was added to maintain the pH value at 10.5 throughout the reaction. The synthesized HAp, drug loaded HAp and drug loaded HAp with gelatin were characterized using PXRD, FTIR, SEM, Drug loading, drug release studies. Results shows that the average crystallite size of the prepared HAp and drug loaded HAp with gelatin are 30 to 60 nm and 100 to 300 nm respectively was calculated using PXRD and morphology of pure HAp and drug loaded HAp with polymer was found using SEM. Drug loading and release percentage was calculated.


2014 ◽  
Vol 599-601 ◽  
pp. 118-123
Author(s):  
Xie Bin Zhu ◽  
Jing Chen ◽  
Zhong Jia Huang

Antimony doped tin oxide (ATO) Nano powder was prepared by co-precipitation method, selecting SnCl4 • 5H2O and SbCl3 as the main raw material, citric acid as dispersant, ammonia solution (1:3) as precipitant, which was characterized, analyzed and tested by XRD, SEM, and digital conductivity meter. The optimum technological condition is that evenly-scattered powder whose crystalline structure is rutile, particle is sphere, size is about 10nm and conductivity is 1.32 ×102 µs/cm can be obtained when the reaction temperature is 60°C, Sb doping ratio is 10%, pH value is 2, calcinations temperature are 600°C and calcinations time are 2 hours.


2007 ◽  
Vol 23 (5-6-2) ◽  
pp. 49-58
Author(s):  
B. Miscevic ◽  
S. Aleksic ◽  
Lj. Sretenovic ◽  
V. Pantelic ◽  
S. Trivunovic ◽  
...  

Investigations were carried out on four muscles (M. longissimus dorsi, M. semimembranosus, M. semitendinosus, M. biceps femoris) taken from five young cattle (crosses Domestic Spotted x Limousine) of average body mass prior to slaughtering of 587 kg. On all muscles, 24 h after slaughtering, sensory evaluation was carried out and the following parameters determined: pH value, colour, water binding ability, cooking loss and tenderness (initial values). The remaining part of each muscle was divided into 6 parts, 3 were packaged in plastic foil (control samples), and other 3 were soaked in solution containing 0,4% CaCl2 and 0,4% NaCl and packaged in plastic foil. Pieces of meat prepared in this way were left on temperature of + 40C 7, 14 and 21 days to mature. After this period, all mentioned analyses were carried out on meat samples. It was established that pH value during maturation increased, that meat packaged in plastic foil after 14 days of maturation becomes unusable, whereas the increase of pH values of meat whose maturation occurred in solution CaCl2 and NaCl was slower and therefore meat was still usable after 21 days. Color of meat in control samples was slightly lighter compared to initial condition, whereas the color of meat whose maturation occurred in solutions of salt was statistically considerably lighter (P<0,05 after 7 days, a P<0,001 after 14 and 21 days). Water binding ability in control samples was slightly better (P>0,05) after 7 days and after 14 days it was statistically significantly better (P<0,05) compared to initial state, whereas in meat whose maturation occurred in salt solution this ability was at initial level even after 21 days. Cooking loss in control samples was lower compared to initial values whereas in meat soaked in salt solution cooking loss was higher. Meat tenderness in control samples was statistically considerably better after 14 days of maturation (when meat was not fit for use) and in meat soaked in salt solution it was statistically highly significantly better after 14 and 21 days. According to sensory evaluation, control samples of meat, after 14 days of maturation are not fit for use, whereas meat whose maturation occurred in solution of CaCl2 and NaCl even after 21 days is acceptable from the sensory aspect.


2019 ◽  
Vol 3 (1) ◽  
pp. 27 ◽  
Author(s):  
Olha Stashkiv ◽  
Volodymyr Vasylechko ◽  
Galyna Gryshchouk ◽  
Ihor Patsay

Sorptive properties of the Transcarpathian clinoptilolite towards Pr(III) were studied under dynamic conditions. The sorption capacity of clinoptilolite under optimal conditions (sorbent grain diameter of 0.20–0.31 mm; pH 9.0, temperature of preliminary precalcination of 350 °C, and flow rate of the Pr(III) salt solution with the concentration of 1.0 μg·mL−1 through the sorbent of 5 mL·min−1) was equal to 47.5 mg·g−1. The best desorbent of Pr from the clinoptilolite was the 1 M solution of KCl acidified with HCl to a pH value of 3.0. The method of Pr(III) trace amounts preconcentration in a solid phase extraction mode with further determination of this REE via spectrophotometric technique was developed. The linearity of the proposed method was evaluated in the range of 2–100 ng·mL−1 with detection limit of 0.7 ng·mL−1.


2016 ◽  
Vol 42 ◽  
pp. 1660183 ◽  
Author(s):  
CHE-RONG CHANG ◽  
CHING-HUA YEH ◽  
HUNG-CHUN YEH ◽  
RUEY-JEN YANG

When a concentrated salt solution and a diluted salt solution are separated by an ion-selective membrane, cations and anions would diffuse at different rates depending on the ion selectivity of the membrane. The difference of positive and negative charges at both ends of the membrane would produce a potential, called the diffusion potential. Thus, electrical energy can be converted from the diffusion potential through reverse electrodialysis. This study demonstrated the fabrication of an energy conversion microchip using the standard micro-electromechanical technique, and utilizing Nafion junction as connecting membrane, which was fabricated by a surface patterned process. Through different salinity gradient of potassium chloride solutions, we experimentally investigated the diffusion potential and power generation from the microchip, and the highest value measured was 135 mV and 339 pW, respectively. Furthermore, when the electrolyte was in pH value of 3.8, 5.6, 10.3, the system exhibited best performance at pH value of 10.3; whereas, pH value of 3.8 yielded the worst.


2011 ◽  
Vol 305 ◽  
pp. 261-264
Author(s):  
Qing Yang ◽  
Xin Qiu ◽  
Xiang Shen

The study discussed the desalination effect of influence factors (operation pressure, salt concentration, pH, ionic valence and etc.) for two different types nanofiltration (NF) (DK and NF90), based on desalination NF characteristics of membrane. The results showed the same desalination characteristics of the two kinds NF that desalination performance decrease directly with NF operation pressure and salt concentration increasing. When pH value was controlled in an acidic range of 4 to 7, it could obtain both high salt removal and membrane flux in salt solution. The salt rejection sequence of two NF was NaCl <MgCl2 <Na2SO4 <MgSO4 <Na3PO4 in different valence salt neuter solution. The different desalination characteristics of two kinds NF showed that monovalent salt rejection of DK (over 35%) was lower than that of NF90 (above 85%). The multivalent salt rejection of two NF showed higher removal efficiency, with DK over 96% and NF90 over 99%.


1966 ◽  
Vol 19 (5) ◽  
pp. 765 ◽  
Author(s):  
DE Weiss ◽  
BA Bolto ◽  
R McNeill ◽  
AS MacPherson ◽  
R Siudak ◽  
...  

The titration curve data at c. 20� and 80� for weakly basic amine and carboxylic acid resins suggest that if a mixed bed of such resins is in equilibrium with a salt solution, then when the temperature of the system is raised, protons will be transferred from the base to the acid resin to an extent determined by the overlap of the titration curves of the resins. Maximum overlap would occur with two resins of appropriate acid and basic strength and which possess plateau-type titration curves, but such acid resins are not available. The theory has been confirmed by experiment. The change in salt adsorption on heating (effective capacity) depends critically on pH and may be enhanced for amine resins of homo-functional structure by increasing the ratio of acid to base resin. It is shown that to achieve the maximum effective capacity for each resin combination there is an optimum pH value and resin ratio. A screening procedure, which uses titration curve data at c. 20� and 80� and allows for the effect of pH and resin ratio, has been devised for selecting resin combinations. In a 0.030M salt solution the effective capacity of the commercial resins studied is greatest, for a poly(vinylbenzyldiethy1amine) resin in combination with a poly(acry1ic acid) resin. A-rigorous procedure has been devised for obtaining equilibrium data, which are presented for this resin combination at c. 20� and 80� in sodium chloride solutions with concentrations ranging from 0.0017 to 0.13M.


2021 ◽  
Vol 1035 ◽  
pp. 534-538
Author(s):  
Xiao Jun Fang ◽  
Li Liu ◽  
Zhi Gang Yang ◽  
Yong Qiang Zhang

The influence of temperature, flow rate, PH value, and oxygen content on the corrosion law in the carbon dioxide salt solution of J55 oil casing was investigated by the corrosion weight loss method. The results showed that with the increase of temperature, the corrosion rate of J55 steel first increased and then decreased and the corrosion rate reached the maximum at 100°C. The corrosion rate was closely related to the formation of corrosion products. The increase of the flow rate speeded up the transfer rate of the corrosive medium to the metal surface and hindered the formation of FeCO3 on the metal surface. The corrosion rate was significantly higher than the corrosion rate under static conditions, and as the flow rate increased, the corrosion rate of J55 steel increased accordingly. The increase of the pH value gradually reduced the concentration of hydrogen ions, and cathodic reaction of hydrogen ion depolarization during metal corrosion process was inhibited, and the tendency to form an oxidizing protective film on the surface of carbon steel increased, thereby reducing the corrosion rate of metals. With the increase of oxygen content, there were both hydrogen evolution reaction of CO2 and oxygen absorption reaction caused by O2 in the cathode process. The corrosion rate of J55 steel gradually increased, and at the same oxygen content, the higher the carbon dioxide content, the greater the corrosion rate is.


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