scholarly journals Concentration of the carcinogenic material in a Venezuelan spindle oil by simultaneous molecular distillation and chromatographic adsorption

1944 ◽  
Vol 43 (4) ◽  
pp. 248-251
Author(s):  
J. M. Twort ◽  
R. Lyth
Keyword(s):  
Molecular Distillation ◽  
Room Temperature ◽  
Adsorption Process ◽  
Active Material ◽  
Animal Experiments ◽  
Practical Work ◽  
Inert Material ◽  
Crystalline Solids ◽  
Low Viscosity ◽  
Adsorption Processes

Some concentration of the carcinogenic material in a Venezuelan spindle grade oil has been affected by simultaneous molecular distillation, and further concentration has also been accomplished by subjecting one of the more carcinogenic of these distillates to chromatographic adsorption. Animal experiments revealed that this distillate was about twice as carcinogenic as the oil from which it was derived. Two small fractions obtained from this distillate by chromatographic adsorption were painted on the skin of a few mice and both appeared to be appreciably more carcinogenic than the distillate from which they were derived. Further experiments with one of these fractions and the distillate, not yet completed, indicate that this fraction is at least five times as strong as the distillate from which it was derived. Thus by a combination of molecular distillation and chromatographic adsorption processes we have obtained a fraction about ten times as strong as the original oil. During the chromatographic adsorption process large quantities of colourless, low index, inert or almost inert material of relatively low viscosity have been separated from the highly coloured active remainder. It would appear that the most active material is highly viscous at room temperature, but its activity may be due to the presence in it of crystalline solids.In conclusion we wish to express our thanks to our steward, Mr L. Norburn, for his valuable assistance in the practical work.

Purification of Eucalyptus globulus water prehydrolyzates using the HiTAC process (high-temperature adsorption on activated charcoal)

Holzforschung ◽  
2011 ◽  
Vol 65 (4) ◽  
Author(s):  
Jenny Sabrina Gütsch ◽  
Herbert Sixta
Keyword(s):  
High Temperature ◽  
Room Temperature ◽  
Adsorption Process ◽  
Value Added ◽  
Sustainable Utilization ◽  
Pulp And Paper Mills ◽  
Paper Mills ◽  
Charcoal Adsorption ◽  
Increasing Temperature ◽  
Value Added Products

Abstract The implementation of biorefinery concepts into existing pulp and paper mills is a key step for a sustainable utilization of the natural resource wood. Water prehydrolysis of wood is an interesting process for the recovery of xylo-oligosaccharides and derivatives thereof, while at the same time cellulose is preserved to a large extent for subsequent dissolving pulp production. The recovery of value-added products out of autohydrolyzates is frequently hindered by extensive lignin precipitation, especially at high temperatures. In this study, a new high-temperature adsorption process (HiTAC process) was developed, where lignin is removed directly after the autohydrolysis, which enables further processing of the autohydrolyzates. The suitability of activated charcoals as a selective adsorbent for lignin under process-relevant conditions (150 and 170°C) has not been considered up to now, because former experiments showed decreasing efficiency of charcoal adsorption of lignin with increasing temperature in the range 20–80°C. In contrast to these results, we demonstrated that the adsorption of lignin at 170°C directly after autohydrolysis is even more efficient than after cooling the hydrolyzate to room temperature. The formation of lignin precipitation and incrustations can thus be efficiently prevented by the HiTAC process. The carbohydrates in the autohydrolysis liquor remain unaffected over a wide charcoal concentration range and can be further processed to yield valuable products.

scholarly journals Synthesis and Characterisation of Thin Films of Bismuth Triiodide for Semiconductor Radiation Detectors

2014 ◽  
Vol 2014 ◽  
pp. 1-3 ◽  
Author(s):  
Alka Garg ◽  
Monika Tomar ◽  
Vinay Gupta
Keyword(s):  
Thin Films ◽  
Absorption Coefficient ◽  
Room Temperature ◽  
Active Material ◽  
Visible Region ◽  
Radiation Detectors ◽  
Radiation Absorption ◽  
X Rays ◽  
X Ray ◽  
Bismuth Iodide

Bismuth iodide is a potentially active material for room temperature radiation detector, as it is well reported in the literature that it has both wide energy band gap and high atomic absorption coefficient. Crystalline films of high atomic number and high radiation absorption coefficient can absorb the X-rays and convert them directly into electrical charges which can be read by imaging devices. Therefore, it was proposed to grow thin films of Bismuth iodide on glass substrate using thermal evaporation technique in vacuum to avoid the inclusion of impurities in the films. The structural studies of the films were carried out using XRD and optical absorption measurement was carried out in the UV/VIS region using spectrophotometer. All Bismuth iodide films grown at room temperature are polycrystalline and show X-ray diffraction peaks at angles reported in research papers. The optical transmission spectra of BiI3 films show a high transmission of about 80% in visible region with a sharp fall near the fundamental absorption at 650 nm. Resistivity of the as-grown film was found to be around 1012 ohm-cm suitable value for X-ray detection application. Films were subjected to scanning electron microscopy to study the growth features of both as-grown and annealed films.

scholarly journals Synthesis, Characterization, and Visible Light Curing Capacity of Polycaprolactone Acrylate

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Jy-Jiunn Tzeng ◽  
Yi-Ting Hsiao ◽  
Yun-Ching Wu ◽  
Hsuan Chen ◽  
Shyh-Yuan Lee ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
3D Printing ◽  
Visible Light ◽  
Room Temperature ◽  
Low Viscosity ◽  
Nuclear Magnetic Resonance Spectra ◽  
Light Curing ◽  
Soft Tissue Engineering ◽  
The Fourier Transform ◽  
Visible Light Curing

Polycaprolactone (PCL) is drawing increasing attention in the field of medical 3D printing and tissue engineering because of its biodegradability. This study developed polycaprolactone prepolymers that can be cured using visible light. Three PCL acrylates were synthesized: polycaprolactone-530 diacrylate (PCL530DA), glycerol-3 caprolactone triacrylate (Glycerol-3CL-TA), and glycerol-6 caprolactone triacrylate (Glycerol-6CL-TA). PCL530DA has two acrylates, whereas Glycerol-3CL-TA and Glycerol-6CL-TA have three acrylates. The Fourier transform infrared and nuclear magnetic resonance spectra suggested successful synthesis of all PCL acrylates. All are liquid at room temperature and can be photopolymerized into a transparent solid after exposure to 470 nm blue LED light using 1% camphorquinone as photoinitiator and 2% dimethylaminoethyl methacrylate as coinitiator. The degree of conversion for all PCL acrylates can reach more than 80% after 1 min of curing. The compressive modulus of PCL530DA, Glycerol-3CL-TA, and Glycerol-6CL-TA is 65.7±12.7, 80.9±6.1, and 32.1±4.1 MPa, respectively, and their compressive strength is 5.3±0.29, 8.3±0.18, and 3.0±0.53 MPa, respectively. Thus, all PCL acrylates synthesized in this study can be photopolymerized and because of their solid structure and low viscosity, they are applicable to soft tissue engineering and medical 3D printing.

Magnetic Enhancement and Nitriding Process of Fe Atomic Layers on Si (111)-7×7-CH3OH Surface

2021 ◽  
Author(s):  
Wenxin Li ◽  
Wanyu Ding ◽  
Youping Gong ◽  
Dongying Ju
Keyword(s):  
Formation Mechanism ◽  
Room Temperature ◽  
Adsorption Process ◽  
Linear Structure ◽  
Atomic Layer ◽  
Residual Magnetization ◽  
Good Stability ◽  
Iron Nitride ◽  
Dissociation Process ◽  
Magnetic Performance

Abstract Fe atoms were steamed on Si(111)-7×7 surface, which had been saturated by CH3OH. Aim to greatly enhance the magnetic performance, nitriding experiments were implemented and adjusted on the existing linear Fe clusters. First of all, the dissociation of CH3OH adsorption process was deducted in detail, which laid a good foundation for the better use of surface quasi-potential. Further to solve the coming problems like weak linearity and low nitriding effect, the formation mechanism of iron-nitride was explored. Atomic layers of Fe deposition are confirmed as the key to NH3 dissociation process (at room temperature). Specifically, the higher Fe atomic layer contacted by NH3, the weaker influence of surface quasi-potential. With the introduction of Ar, Fe deposition could be controlled at 1-2 atomic layers, result in good NH3 dissociation and nitriding efficiency. Combing with magnetic performance result, the density of residual magnetization is improved from 1.5E-0.5 emu to 7.0E-0.5 emu, forming an obvious linear structure. It is also proved that our new linear iron-nitride clusters will maintain good stability with the improvement of nitriding efficiency.PACS: 07.79.Cz; 81.15.-z; 75.75.Fk

Enhanced decolorization of dyes by an iron modified clay and thermodynamic parameters

2016 ◽  
Vol 73 (8) ◽  
pp. 2007-2016 ◽  
Author(s):  
N. Contreras Olivares ◽  
M. C. Díaz-Nava ◽  
M. Solache-Ríos
Keyword(s):  
Thermodynamic Parameters ◽  
Adsorption Process ◽  
Sorption Kinetics ◽  
Homogeneous Material ◽  
Modified Clay ◽  
Adsorption Capacities ◽  
Adsorption Processes ◽  
Kinetics And Isotherms ◽  
Material Temperature ◽  
Maximum Removal

The sorption processes of red 5 (R5) and yellow 5 (Y5) dyes by iron modified and sodium bentonite in aqueous solutions was evaluated. The modified clay was prepared, conditioned and characterized. The sodium clay did not remove any of either dye. The sorption kinetics and isotherms of R5 and Y5 dyes by iron modified clay were determined. The maximum removal percentages achieved were 97% and 98% for R5 and Y5, respectively, and a contact time of 72 h; the experimental data were best adjusted to Ho model. The isotherms of both dyes were best adjusted to the Langmuir model and the maximum adsorption capacities of the modified clay were 11.26 mg/g and 5.28 mg/g for R5 and Y5, respectively. These results indicate that adsorption processes have a high probability to be described as chemisorption on a homogeneous material. Temperature range between 283 and 213 K does not affect the adsorption of Y5 by the iron modified clay, but the adsorption process of R5 was affected, and the thermodynamic parameters could be calculated, which indicate a chemisorption mechanism.

Paper 33: Hydrodynamics of Surface Films: Modelling Laws for Two-Phase Flows Containing Dilute Surfactant

1967 ◽  
Vol 182 (8) ◽  
pp. 320-329
Author(s):  
D. B. R. Kenning
Keyword(s):  
Open Channel ◽  
Adsorption Process ◽  
Active Material ◽  
Surface Adsorption ◽  
Open Channel Flow ◽  
Surface Films ◽  
Two Phase Flows ◽  
Two Phase ◽  
Surface Active ◽  
Surface Active Material

The presence of surface-active material may modify appreciably the flow patterns in two-phase flows. A frequently employed model for the surface adsorption process is used to derive similarity conditions for such flows. The limitations of this model are discussed in relation to the formation of surface films on open channel flow of water containing dilute surfactant.

Room-temperature synthesis of crystalline solids in the system ZnOP2O5RH2O, with R being an alkylamine or an alkylammonium ion

Zeolites ◽  
1994 ◽  
Vol 14 (6) ◽  
pp. 402-410 ◽  
Author(s):  
M. Wallau ◽  
J. Patarin ◽  
I. Widmer ◽  
P. Caullet ◽  
J.L. Guth ◽  
...  
Keyword(s):  
Room Temperature ◽  
Crystalline Solids ◽  
Temperature Synthesis ◽  
Room Temperature Synthesis

scholarly journals Batch studies of phosphonate adsorption on granular ferric hydroxides

2020 ◽  
Vol 81 (1) ◽  
pp. 10-20 ◽  
Author(s):  
T. Reinhardt ◽  
M. Gómez Elordi ◽  
R. Minke ◽  
H. Schönberger ◽  
E. Rott
Keyword(s):  
Contact Time ◽  
Room Temperature ◽  
Adsorption Process ◽  
Ferric Hydroxide ◽  
Batch Experiments ◽  
Batch Studies ◽  
Influence Of Temperature ◽  
Ph Values ◽  
Adsorption Desorption ◽  
Granular Ferric Hydroxide

Abstract Phosphonates are widely used in various industries. It is desirable to remove them before discharging phosphonate-containing wastewater. This study describes a large number of batch experiments with adsorbents that are likely suitable for the removal of phosphonates. For this, adsorption isotherms for four different granular ferric hydroxide (GFH) adsorbents were determined at different pH values in order to identify the best performing material. Additionally, the influence of temperature was studied for this GFH. A maximum loading for nitrilotrimethylphosphonic acid (NTMP) was found to be ∼12 mg P/g with an initial concentration of 1 mg/L NTMP-P and a contact time of 7 days at room temperature. Then, the adsorption of six different phosphonates was investigated as a function of pH. It was shown that GFH could be used to remove all investigated phosphonates from water and, with an increasing pH, the adsorption capacity decreased for all six phosphonates. Finally, five adsorption–desorption cycles were carried out to check the suitability of the material for multiple re-use. Even after five cycles, the adsorption process still performed well.

scholarly journals Characterization and Evaluation of Zeolite A/Fe3O4 Nanocomposite as a Potential Adsorbent for Removal of Organic Molecules from Wastewater

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Emmanuel Nyankson ◽  
Jonas Adjasoo ◽  
Johnson Kwame Efavi ◽  
Reuben Amedalor ◽  
Abu Yaya ◽  
...  
Keyword(s):  
Adsorption Process ◽  
Isotherm Models ◽  
Adsorption Efficiency ◽  
Ferrous Chloride ◽  
X Ray ◽  
Intraparticle Diffusion Model ◽  
Adsorption Processes ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Chloride Salts

In this work, zeolite (Z) and Z-Fe3O4 nanocomposite (Z-Fe3O4 NC) have been synthesized. The Fe3O4 nanoparticles were synthesized using the extract from maize leaves and ferric and ferrous chloride salts and encapsulated into the zeolite framework. The nanocomposite (Z-Fe3O4 NC) was characterized using X-ray diffractometer (XRD), Fourier-transform infrared (FT-IR) spectroscopy, energy-dispersive X-ray (EDX) spectroscopy, and scanning electron microscopy (SEM). The potential of Z-Fe3O4 NC as an adsorbent for removing methylene blue molecules (MB) from solution was examined using UV-Vis and kinetic and equilibrium isotherm models. The adsorption data fitted best with the pseudo-second-order model and Weber and Morris model, indicating that the adsorption process was chemisorption, while the Weber and Morris described the rate-controlling steps. The intraparticle diffusion model suggests that the adsorption processes were pore and surface diffusion controlled. The Langmuir isotherm model best describes the adsorption process indicating homogeneous monolayer coverage of MB molecules onto the surface of the Z-Fe3O4 NC. The maximum Langmuir adsorption capacity was 2.57 mg/g at 25°C. The maximum adsorption efficiency was 97.5%. After regeneration, the maximum adsorption efficiency achieved at a pH of 7 was 82.6%.

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