The Effect of Temperature and Initial Concentration on Synthesis of Ammonia Borane

2015 ◽  
pp. 571-576
Author(s):  
Derya Öncel Özgür ◽  
Göksel Özkan
Keyword(s):  
Ammonia Borane ◽  
Effect Of Temperature ◽  
Initial Concentration

Preparation of Persimmon Tannins Immobilized on Collagen Adsorbent and Research on its Adsorption to Cr(VI)

2013 ◽  
Vol 743-744 ◽  
pp. 523-530 ◽  
Author(s):  
Jian Cui ◽  
Zhong Min Wang ◽  
Feng Lei Liu ◽  
Pei Bang Dai ◽  
Ran Chen ◽  
...  
Keyword(s):  
Adsorption Mechanism ◽  
Ph Value ◽  
Effect Of Temperature ◽  
Major Influence ◽  
Initial Concentration ◽  
Adsorbent Dosage ◽  
Adsorption Data ◽  
Initial Ph ◽  
Pseudo Second Order ◽  
Ph Range

Persimmon tannins (PT) were immobilized on a matrix of collagen fiber by cross-linking of glutaraldehyde. The adsorption behaviours to Cr (VI) on PT were investigated including the effects of initial pH, initial concentration of Cr (VI), temperature, adsorbent dosage, adsorption kinetics and the recycling performance of PT adsorbents. The results showed that pH value had a major influence in adsorption. PT showed a strong adsorbability to Cr (VI) in the pH range of 1.0 to 3.0, whereas the effect of temperature on the adsorption was comparatively weaker. The adsorption equilibrium could be well described by Freundlich equation. PT adsorption efficiency of Cr (VI) reached 98.04% and the maximum equilibrium adsorption capacity of Cr (VI) was up to 49.01 mg/g at 303 K with a pH value of 2.0, 100 mg/L of initial concentration of Cr (VI) and 0.1g of adsorbent dosage. The adsorption data could be well fitted by pseudo-second-order rate model. PT adsorbents were characterized by FTIR and EDS. The analysis indicated that the adsorption mechanism was mainly contributed by redox adsorption.

scholarly journals Effects of Temperature and Aeration on The Dissolved Oxygen (DO) Values in Freshwater Using Simple Water Bath Reactor: A Brief Report

2020 ◽  
Vol 3 (1) ◽  
pp. 25
Author(s):  
Febiyanto Febiyanto
Keyword(s):  
Dissolved Oxygen ◽  
Room Temperature ◽  
Temperature Treatment ◽  
Water Bath ◽  
Effect Of Temperature ◽  
Initial Concentration ◽  
Freshwater Sample ◽  
Effects Of Temperature ◽  
And Control

<em>This work investigated the effect of temperature and aeration treatments on the dissolved oxygen (DO) values in freshwater. The study was carried out using a simple water bath reactor in room temperature condition. Based on the results, freshwater sample without the aeration and temperature treatments (control) indicates a fluctuating profile on which the obtained values of DO were 4.21-4.98 mg/L at T<sub>average </sub>= 27.7 °C. However, the aeration treatment was slightly able to enhance the DO value up to 8.12 mg/L from the initial concentration of 3.88 mg/L at T<sub>average </sub>= 27.4 °C. Compared to the aeration treatment, the addition of temperature treatment has extremely increased the DO value up to 21 mg/L from 6.6 mg/L (T<sub>0 minutes</sub> = 27 °C)  for 20 minutes of DO observation (T<sub>20 minutes</sub> = 12.4 °C). Hence, this brief report suggests that the addition of temperature treatment gave a significant effect on the DO value in freshwater than the aeration treatment and control.</em>

scholarly journals Modification of Activated Carbon (Prepared From Flaxseed) With Fe3O4, Its Application As Adsorbent And Antibacterial

2021 ◽  
Author(s):  
M. H. Fekri ◽  
S. Isanejad Mohamareh ◽  
M. Hosseini ◽  
M. Razavi Mehr
Keyword(s):  
Activated Carbon ◽  
Contact Time ◽  
Structural Characteristics ◽  
Antibacterial Properties ◽  
Effect Of Temperature ◽  
Maximum Efficiency ◽  
Process Conditions ◽  
Nano Composite ◽  
Initial Concentration ◽  
Central Composite

Abstract In this work, magnetic activated carbon (MGAC) was investigated to remove the antibiotic cefazolin from aqueous solutions as well as its antibacterial properties. To determine the optimal process conditions and achieve maximum efficiency, the effect of temperature, contact time, initial concentration of the drug, composite dosage, and pH using the response surface method (RSM) and the central composite design model (CCD) were investigated by DOE software. Structural characteristics and morphology of the nanocomposite were analyzed by using FTIR, XRD, EDAX, SEM, TEM, BET, TGA, VSM, analyzes. The results showed that pH = 6, the temperature of 30 ℃, contact time 150 minutes, initial concentration of drug 20 mg/l, and composite dosage 0.03 g were the best conditions for removing cefazolin from aqueous solution. In these conditions, the magnetically activated carbon was able to remove 96% of cefazolin. The Langmuir, Freundlich, and Temkin isotherms were also studied and the results showed that the absorption behavior is most consistent with the Temkin isotherm. The results of thermodynamic experiments also showed that the adsorption process is exothermic and spontaneous. Finally, the antibacterial properties of the prepared nano composite on Streptococcus and Salmonella were investigated and the results showed that the prepared sample has antibacterial properties.

Treatment of Pb2+-Containing Mine Wastewater with Layered Nanometer Zinc Hydroxide

2012 ◽  
Vol 550-553 ◽  
pp. 2081-2084
Author(s):  
Hai Hong Jia ◽  
Guo Xiang Xu ◽  
Hong Ying Zhou
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Removal Efficiency ◽  
Metal Ion ◽  
Heavy Metal Ions ◽  
Effect Of Temperature ◽  
Zinc Hydroxide ◽  
Initial Concentration ◽  
Mine Wastewater ◽  
Coexisting Ions

Experiment was made to study heavy metal ion mining wastewater.The effect of Temperature, pH, Initial concentration, coexisting ions and time on the performance of Nanomaterials were investigated. Results showed that removal efficiency of heavy metal ions was higher than 85% and Pb2+ concentration in permeation liquid was lower than 0.5 mg/L,which verified that Nanomaterials is effective for the removal of heavy metal ions, and the concentration liquid can be reclaimed.

Nucleation of Disorder in Fe3Al Alloys

1967 ◽  
Vol 25 ◽  
pp. 312-313
Author(s):  
P. R. Swann ◽  
W. R. Duff ◽  
R. M. Fisher
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Annealing Temperature ◽  
Antiphase Domain ◽  
Effect Of Temperature ◽  
Domain Structures ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Higher Temperature ◽  
The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

The effect of temperature on high-resolution TEM image contrast

1995 ◽  
Vol 53 ◽  
pp. 640-641
Author(s):  
T. Geipel ◽  
W. Mader ◽  
P. Pirouz
Keyword(s):  
Form Factor ◽  
Inelastic Scattering ◽  
Accurate Method ◽  
Waller Factor ◽  
Effect Of Temperature ◽  
Specimen Thickness ◽  
Influence Of Temperature ◽  
Debye Waller Factor ◽  
Influence Of Temperature On ◽  
Atomic Form Factor

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).

The development of dormancy in bulblets of Lilium speciosum generated in vitro. II. The effect of temperature

1990 ◽  
Vol 80 (3) ◽  
pp. 431-436 ◽  
Author(s):  
Isabelle Delvallee ◽  
Annie Paffen ◽  
Geert-Jan De Klerk
Keyword(s):  
Effect Of Temperature ◽  
Lilium Speciosum

Effect of Temperature on ADP-Induced Platelet Aggregation

1973 ◽  
Vol 29 (01) ◽  
pp. 183-189
Author(s):  
C. A Praga ◽  
E. M Pogliani
Keyword(s):  
Platelet Aggregation ◽  
Incubation Period ◽  
Room Temperature ◽  
Important Variable ◽  
Practical Significance ◽  
Effect Of Temperature ◽  
Induce Platelet Aggregation ◽  
Cuvette Holder ◽  
Exact Temperature

SummaryTemperature represents a very important variable in ADP-induced platelet aggregation.When low doses of ADP ( < 1 (μM) are used to induce platelet aggregation, the length of the incubation period of PRP in the cuvette holder of the aggregometer, thermostatted at 37° C, is very critical. Samples of the same PRP previously kept at room temperature, were incubated for increasing periods of time in the cuvette of the aggregometer before adding ADP, and a significant decrease of aggregation, proportional to the length of incubation, was observed. Stirring of the PRP during the incubation period made these changes more evident.To measure the exact temperature of the PRP during incubation in the aggre- gometer, a thermocouple device was used. While the temperature of the cuvette holder was stable at 37° C, the PRP temperature itself increased exponentially, taking about ten minutes from the beginning of the incubation to reach the value of 37° C. The above results have a practical significance in the reproducibility of the platelet aggregation test in vitro and acquire particular value when the effect of inhibitors of ADP induced platelet aggregation is studied.Experiments carried out with three anti-aggregating agents (acetyl salicyclic acid, dipyridamole and metergoline) have shown that the incubation conditions which influence both the effect of the drugs on platelets and the ADP breakdown in plasma must be strictly controlled.

Effect of Temperature, Velocity Gradient and I.V. Heparin on in Vitro Blood Coagulation and Platelet Aggregation

1967 ◽  
Vol 17 (01/02) ◽  
pp. 112-119 ◽  
Author(s):  
L Dintenfass ◽  
M. C Rozenberg
Keyword(s):  
Blood Coagulation ◽  
Velocity Gradient ◽  
Elevated Temperatures ◽  
Morphological Changes ◽  
Effect Of Temperature ◽  
Clotting Time ◽  
Progressive Change ◽  
Aggregation Of Platelets ◽  
Microscopic Techniques

SummaryA study of blood coagulation was carried out by observing changes in the blood viscosity of blood coagulating in the cone-in-cone viscometer. The clots were investigated by microscopic techniques.Immediately after blood is obtained by venepuncture, viscosity of blood remains constant for a certain “latent” period. The duration of this period depends not only on the intrinsic properties of the blood sample, but also on temperature and rate of shear used during blood storage. An increase of temperature decreases the clotting time ; also, an increase in the rate of shear decreases the clotting time.It is confirmed that morphological changes take place in blood coagula as a function of the velocity gradient at which such coagulation takes place. There is a progressive change from the red clot to white thrombus as the rates of shear increase. Aggregation of platelets increases as the rate of shear increases.This pattern is maintained with changes of temperature, although aggregation of platelets appears to be increased at elevated temperatures.Intravenously added heparin affects the clotting time and the aggregation of platelets in in vitro coagulation.

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