scholarly journals Degradability of polylactide films by commercial microbiological preparations for household composters

2017 ◽  
Vol 19 (3) ◽  
pp. 44-48 ◽  
Author(s):  
Magda Morawska ◽  
Katarzyna Krasowska
Keyword(s):  
Renewable Resources ◽  
Soil Microorganisms ◽  
Silicon Oxide ◽  
Environmentally Friendly ◽  
Commercial Preparation ◽  
Chemical Hydrolysis ◽  
Before And After ◽  
Surface Changes

AbstractEnvironmentally friendly polymers such as polylactide are increasingly becoming available for use in packaging applications. The main advantages of polylactide packaging are evident. Polylactide is based on renewable resources and can be degraded in compost or soil. The studies on degradability of polylactide (PLA) films by commercial preparation of mixture of multi-active saprophytic soil microorganisms, bacteria, actinomycetes and fungi have been done. Unmodified PLA film, metalized co-extruded PLA film and modified by silicon oxide PLA film were incubated in the liquid nutritious medium (TSB) prepared to support the growth of microorganisms. The degradability of polylactide films was examined by macro and microscopic observations of surface, changes of mass and crystallinity of polymer samples before and after incubation. The obtained results indicate that the degradation of polylactide was accelerated by the presence of a biological vaccine. It was found that PLA degradation in the inoculated TSB broth was a result of both: enzymatic and chemical hydrolysis.

Sorption Resistance Studying of Environmentally Friendly Polymeric Materials in Different Liquid Mediums

2021 ◽  
Vol 1038 ◽  
pp. 168-174
Author(s):  
Vladimir Lebedev ◽  
Tetiana Tykhomyrova ◽  
Olesia Filenko ◽  
Anna Cherkashina ◽  
Oleksandr Lytvynenko
Keyword(s):  
Diffusion Coefficient ◽  
Microscopic Analysis ◽  
Environmentally Friendly ◽  
Polymeric Materials ◽  
Coffee Grounds ◽  
Size Stability ◽  
Before And After ◽  
And Diffusion ◽  
Surface Changes

Sorption resistances of environmentally friendly polymeric materials in different liquid mediums are studying in this work. As part of environmentally friendly polymeric materials based on polylactide, OK compost HOME plastic and coffee grounds sorption studying in different liquid mediums, the most stable compositions were identified in terms of size stability and diffusion coefficient. microscopic analysis of new environmentally friendly polymeric materials before and after exposure in operating liquid mediums was made and compositions with the least surface changes were determined.

scholarly journals ENVIRONMENTALLY SAFE SYNTHESIS OF HYDROGENATION NICKEL CATALYSTS

2019 ◽  
Vol 62 (9) ◽  
pp. 46-52 ◽  
Author(s):  
Adele R. Latypova ◽  
Dmitry V. Filippov ◽  
Olga V. Lefedova ◽  
Alexey V. Bykov ◽  
Valentin Yu. Doluda
Keyword(s):  
Photoelectron Spectroscopy ◽  
Hydrogen Pressure ◽  
Silicon Oxide ◽  
Environmentally Friendly ◽  
Nickel Catalysts ◽  
Catalyst Activation ◽  
Gas Atmosphere ◽  
Before And After ◽  
Environmentally Safe ◽  
Lower Temperature

New types of nickel catalysts are proposed. They are formed during the surface deposition of nickel polynuclear hydroxo complexes on powdered carriers with subsequent reduction to the metal. This method of synthesis is environmentally friendly, safe and waste-free technology. Industrial wastewater will contain only an aqueous solution of sodium chloride and sodium carbonate. The catalytic activity was determined by the p-nitroaniline hydrogenation at 240 °C and 40 bar of hydrogen pressure. The properties and characteristics of the catalysts were studied using thermo-programmable desorption of ammonia, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. It was found that Ni/γ-Al2O3 catalyst may accelerate the process with NiO, NiO, γ-NiOOH and Ni(OH)2 compounds, while for Ni/SiO2 these are NiO, NiO, Ni2O3, γ-NiOOH and Ni(OH)2. However, pre-activation of the sample is necessary. The solution of this problem can be the catalyst activation in a gas atmosphere under hydrogen pressure, but at a lower temperature of about 250 °C. Changes in the metal content in the catalysts before and after use may be associated with the mutual transformations of modifications, which may or may not depend on the catalysis of the hydrogenation process. We established that the catalyst supported on gamma alumina was 10 times more active than the catalyst on silicon oxide. The discovery of the mechanism of transformations between modifications of oxides and metal hydroxides is of considerable interest in the development of new selective and environmentally friendly catalysts.

Mechanoactivation Of Rice Husk Ash In Laboratory Conditions

2019 ◽  
pp. 20-26
Keyword(s):  
Mechanical Activation ◽  
Rice Husk ◽  
Amorphous Silica ◽  
Silicon Oxide ◽  
Rice Husk Ash ◽  
Pozzolanic Activity ◽  
Maximum Solubility ◽  
Laboratory Conditions ◽  
Before And After ◽  
Mineral Additive

In many rice producing countries of the world, including in Vietnam, various research aimed at using rice husk ash (RHA) as a finely dispersed active mineral additive in cements, concrete and mortars are being conducted. The effect of the duration of the mechanoactivation of the RHA, produced under laboratory conditions in Vietnam, on its pozzolanic activity were investigated in this study. The composition of ash was investigated by laser granulometry and the values of indicators characterizing the dispersion of its particles before and after mechanical activation were established. The content of soluble amorphous silicon oxide in rice husk ash samples was determined by photocolorimetric analysis. The pizzolanic activity of the RHA, fly ash and the silica fume was also compared according to the method of absorption of the solution of the active mineral additive. It is established that the duration of the mechanical activation of rice husk ash by grinding in a vibratory mill is optimal for increasing its pozzolanic activity, since it simultaneously results in the production of the most dispersed ash particles with the highest specific surface area and maximum solubility of the amorphous silica contained in it. Longer grinding does not lead to further reduction in the size of ash particles, which can be explained by their aggregation, and also reduces the solubility of amorphous silica in an aqueous alkaline medium.

An Environmentally Friendly Technology for Biomass Production Hydorchar from Renewable Resources

2013 ◽  
Vol 726-731 ◽  
pp. 634-637 ◽  
Author(s):  
Yan Qiu Lei ◽  
Hai Quan Su
Keyword(s):  
Activated Carbon ◽  
Reaction Time ◽  
Adsorption Capacity ◽  
Functional Groups ◽  
Biomass Production ◽  
Renewable Resources ◽  
Environmentally Friendly ◽  
Hydrothermal Carbonization ◽  
Removal Rates

A green and sustainable route for preparation of hydrochars from cornstalk by hydrothermal carbonization (200°C) was described. The morphology of the hydrochars changed with reaction time increased, the surface of the materials contained a large number of functional groups, showed higher adsorption capacity for Cr (VI) than activated carbon and the removal rates of Cr (VI) were 67% and 29% respectively (pH=1, 20°C).

Preparation and characterization of a [14C]cellulose suitable for human metabolic studies

1989 ◽  
Vol 62 (1) ◽  
pp. 121-129 ◽  
Author(s):  
M. P. Walters ◽  
J. Kelleher ◽  
J. M. Findlay ◽  
S. T. Srinivasan
Keyword(s):  
Normal Subjects ◽  
Microscopical Examination ◽  
Cellulosic Material ◽  
Commercial Preparation ◽  
Before And After ◽  
Cumulative Excretion ◽  
Normal Controls ◽  
Subsequent Administration ◽  
Expired Air

In six normal subjects administered 5 μCi of an oral dose of a commercially available 14C-labelled cellulose, significant amounts of 14CO2 were detected in expired air within 30 min, suggesting that other 14C-labelled non-cellulosic material was present. Chemical and microscopical examination confirmed that starch was the principal contaminant. The commercial preparation was purified using amyloglucosidase (EC 3.2.1.3) digestion following gelatinization of the starch by autoclaving. Subsequent administration of the purified cellulose to a further six normal subjects decreased the expired air 14CO2 during the subsequent 10 h from 13.0 (sd 4.0) to 4.1 (sd 1.9)%. Administration of the purified product to a further group of four normal subjects, before and after a regimen of increased dietary fibre, showed a cumulative increase in expired 14CO2 over 24 h from 7.9 (sd 1.1) to 12.1 (sd 2.6) % on fibre. In six ileostomy subjects the cumulative excretion of 14CO2 was greatly decreased compared with normal controls (3.0 (sd 1.14) and 10.5 (sd 3.9) % respectively). In constipated subjects expired 14CO2 continued beyond 48 h, in contrast to normal subjects where expired 14CO2 at this time was negligible.

Physical and electrical characterization of TiO2 particles after high temperature processing and before and after ultraviolet irradiation

2014 ◽  
Vol 92 (7/8) ◽  
pp. 832-837
Author(s):  
J. Molina ◽  
C. Zúñiga ◽  
M. Moreno ◽  
W. Calleja ◽  
P. Rosales ◽  
...  
Keyword(s):  
High Temperature ◽  
Thermal Treatment ◽  
Uv Irradiation ◽  
Silicon Oxide ◽  
Crystalline Silicon ◽  
Electrical Characterization ◽  
Metal Electrode ◽  
Rutile Phase ◽  
Before And After ◽  
Diffraction Patterns

In this work, rutile-phase TiO2 particles (r-TiO2, about 360 nm in size) are embedded within a silicon oxide matrix using different concentration ratios of r-TiO2 with respect to SiO2:H2O, so that suspensions of mixed TiO2:SiO2 oxides were obtained and analyzed. These TiO2:SiO2 suspensions were deposited on previously-cleaned crystalline silicon and quartz substrates so that thin films of TiO2:SiO2 were obtained. All films were then exposed to relatively high-temperature thermal treatments in nitrogen and different characterization techniques were used to determine their physical and electrical properties before and after ultraviolet (UV) irradiation. Before high thermal treatment, X-ray diffraction patterns show that the main diffraction peaks for the obtained TiO2:SiO2 films correspond to the crystalline phase of rutile-TiO2. Infrared analyses before and after thermal treatment show significant changes in the chemical bonding of the final films relative to the temperatures used during annealing. Also, UV–visible spectra provide a constant optical band gap for the films, independent of different TiO2 concentrations as expected. On the other hand, atomic-force microscopy measurements before and after UV irradiation show an appreciable difference in the grain size and surface morphology of the resulting TiO2:SiO2 oxides annealed at 1000 °C. Finally, photoelectrical I–V properties were obtained for all TiO2:SiO2 films by depositing ultrathin titanium stripes on top of the photoactive material and then, measuring the total current flowing through the metal electrode before and after UV irradiation. From these last measurements, a detectable increase in the I–V slope (lower resistance of the titanium stripe) is found for all samples during UV exposure, thus making this device to act as a simple photoresistor based on r-TiO2 particles.

scholarly journals Calculated Optimized Structure and Geometric Analysis of Oxygenated Fuel Additives: Alcohols and Ethers

2020 ◽  
Vol 10 (3) ◽  
pp. 5632-5636
Author(s):  
S. Gurkan Aydin ◽  
O. Polat ◽  
A. Ozgen ◽  
E. Turali
Keyword(s):  
Physical Properties ◽  
Renewable Resources ◽  
Octane Number ◽  
Geometric Analysis ◽  
Environmentally Friendly ◽  
Fuel Additives ◽  
Future Studies ◽  
Oxygenated Fuel ◽  
Oxygen Fuel

Oxygenated fuel additives are added to gasoline in order to reduce the gases released from vehicle engines, to increase the octane number, and to expand the use of renewable resources. In this study, molecular and geometric analysis of oxygenated fuel additives was conducted theoretically and the energy values of optimized structures were calculated. The effect of molecular energy and the bond structure between C, H and O on the chemical and physical properties of some oxygen fuel additives were investigated. The obtained results will form the basis for future studies in obtaining more environmentally friendly fuels.

Characteristics of UV Irradiated Waste Biopolymer from Renewable Resources (Part 2)

2014 ◽  
Vol 974 ◽  
pp. 257-261 ◽  
Author(s):  
Shaiqah Mohd Rus ◽  
Mohd Imran bin Ghazali ◽  
Anika Zafiah M. Rus
Keyword(s):  
Uv Irradiation ◽  
Renewable Resources ◽  
Damping Ratio ◽  
Developed Countries ◽  
Waste Cooking Oil ◽  
Major Influence ◽  
Good Service ◽  
Cooking Oil ◽  
Before And After ◽  
The Developed Countries

In the developed countries, waste cooking oil has proven to be a problematic material since people usually pour waste cooking oil into the kitchen drainage because they unaware that this waste can be recycled. In this study, the waste cooking oil was converted into polymer, fabricated by using hot compression machine and named as waste biopolymer (WB). WB characteristics before and after UV-irradiated such as vibration damping, density and surface morphology were analysed in this study. Total damping ratio of WB changes more than 5% after 1000 hour UV-irradiation. UV-irradiation does not give major influence to the WB morphology since there is no big change for overall structure of UV-irradiated WB after 1000 hours of UV. Even though the density of UV-irradiated WB is decreasing with increasing exposure time to UV, but it gives good influence to the damping ratio. WB is expected to have a good service life even in a harsh UV environment thus it can be applied in many applications especially in automotive field and manufacturing packaging.

The Effects of Friction and Wear on PECVD Diamond Films.

1994 ◽  
Vol 339 ◽  
Author(s):  
M. L. Languell ◽  
J. L. Davidson ◽  
J. J. Wert ◽  
M. A. George ◽  
W. E. Collins ◽  
...  
Keyword(s):  
Vapor Deposition ◽  
Friction And Wear ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Nasa Lewis Research ◽  
Force Microscopy ◽  
Atomic Force ◽  
Mean Diameter ◽  
Before And After ◽  
Surface Changes

ABSTRACTThe effects of friction and wear were examined on plasma enhanced chemical vapor deposition (PECVD) diamond films deposited on tungsten substrates. The tribology of diamond on diamond was studied and the changes in surface roughness and the bearing ratio were determined before and after wear. The (111) textured heteroepitaxial films were studied morphologically by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The changes in morphology involved a transition from the large as grown diamond crystallites with a mean diameter of 10 μm to a surface with grains as small as 100 nm. The nature of the wear-modified films will be discussed regarding the possible mechanisms for the surface changes.Work partially supported by NASA Lewis Research Center grant NAG3–1430.

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