scholarly journals The Sewage Sludge Biochar and Its Composts Influence the Phosphate Sorption in an Alkaline–Calcareous Soil

2021 ◽  
Vol 13 (4) ◽  
pp. 1779
Author(s):  
Rabia Abdur Rehman ◽  
Muhammad Farooq Qayyum ◽  
Ghulam Haider ◽  
Kate Schofield ◽  
Muhammad Abid ◽  
...  

This study evaluates the potential of sewage sludge, farm manure, rock phosphate, and their composts or biochar as useful materials for phosphorous (P) recovery. An alkaline–calcareous soil was incubated with different compost-based amendments to discern their impact on the P sorption characteristics. The treatments examined consisted of sewage sludge (SS), SS biochar (SS-BC), or composts of SS with rock phosphate (RP) and farm manure (FM) in different ratios, i.e., (i) control, (ii) SS, (iii) SS-BC, (iv) SS50:FM50, (v) SS75:FM25, (vi) SS25:FM25:RP50, (vii) SS50:FM25:RP25, (viii) SS75:FM0:RP25, and (ix) SS50:FM0:RP50. Prior to incubation for 45 days, the composts and biochar treatments combinations were characterized for elemental composition using Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) spectroscopy. The treated soils were analyzed for soil pH, electrical conductivity (EC), Olsen’s P, and P adsorption isotherms, at day 5 and 45 of the incubation. Langmuir and Freundlich’s equations were used to calculate P adsorption. Results showed that there was no significant influence on soil pH for any treatment throughout the experiment. However, soil EC decreased significantly for all treatments after 5 days of incubation; however, this effect was diminished after 45 days of incubation. All the treatments significantly decreased P sorption capacity both at the start (day 5) and end of the incubation (day 45) period compared to control. The treatment combination SS25:FM25:RP50 recovered the highest Olsen-P (79.41 mg kg−1). The other treatment combinations including SS and FM also recovered a greater Olsen’s P compared to the control. However, the sole application of only SS showed lower P recovery than the control soil, which further decreased with increase in incubation time. These findings improve our understanding that the stable pool of bioavailable P within an alkaline calcareous soil can be mobilized by using different organic treatment combinations instead of only SS. However, further in situ investigations may help to valorize the potential of sewage sludge, farm manure, rock phosphate, and their composts or biochar to improve P recovery in alkaline–calcareous.

Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


Author(s):  
J. T. Sizemore ◽  
D. G. Schlom ◽  
Z. J. Chen ◽  
J. N. Eckstein ◽  
I. Bozovic ◽  
...  

Investigators observe large critical currents for superconducting thin films deposited epitaxially on single crystal substrates. The orientation of these films is often characterized by specifying the unit cell axis that is perpendicular to the substrate. This omits specifying the orientation of the other unit cell axes and grain boundary angles between grains of the thin film. Misorientation between grains of YBa2Cu3O7−δ decreases the critical current, even in those films that are c axis oriented. We presume that these results are similar for bismuth based superconductors and report the epitaxial orientations and textures observed in such films.Thin films of nominally Bi2Sr2CaCu2Ox were deposited on MgO using molecular beam epitaxy (MBE). These films were in situ grown (during growth oxygen was incorporated and the films were not oxygen post-annealed) and shuttering was used to encourage c axis growth. Other papers report the details of the synthesis procedure. The films were characterized using x-ray diffraction (XRD) and transmission electron microscopy (TEM).


Author(s):  
G. A. Bertero ◽  
W.H. Hofmeister ◽  
N.D. Evans ◽  
J.E. Wittig ◽  
R.J. Bayuzick

Rapid solidification of Ni-Nb alloys promotes the formation of amorphous structure. Preliminary results indicate promising elastic properties and high fracture strength for the metallic glass. Knowledge of the thermal stability of the amorphus alloy and the changes in properties with temperature is therefore of prime importance. In this work rapidly solidified Ni-Nb alloys were analyzed with transmission electron microscopy (TEM) during in-situ heating experiments and after isothermal annealing of bulk samples. Differential thermal analysis (DTA), scanning electron microscopy (SEM) and x-ray diffraction (XRD) techniques were also used to characterize both the solidification and devitrification sequences.Samples of Ni-44 at.% Nb were electromagnetically levitated, melted, and rapidly solidified by splatquenching between two copper chill plates. The resulting samples were 100 to 200 μm thick discs of 2 to 3 cm diameter. TEM specimens were either ion-milled or alternatively electropolished in a methanol-10% sulphuric acid solution at 20 V and −40°C.


2017 ◽  
Vol 72 (6) ◽  
pp. 355-364
Author(s):  
A. Kopp ◽  
T. Bernthaler ◽  
D. Schmid ◽  
G. Ketzer-Raichle ◽  
G. Schneider

Author(s):  
A. Safonov ◽  
N. Andriushchenko ◽  
N. Popova ◽  
K. Boldyrev

Проведен анализ сорбционных характеристик природных материалов (вермикулит, керамзит, перлит, цеолит Трейд ) при очистке кадмий- и хромсодержащих сточных вод с высокой нагрузкой по ХПК. Установлено, что цеолит обладает максимальными сорбционными характеристиками для Cd и Cr и наименьшим биологическим обрастанием. При использовании вермикулита и керамзита или смесей на их основе можно ожидать увеличения сорбционной емкости для Cd и Сr при микробном обрастании, неизбежно происходящем в условиях контакта с водами, загрязненными органическими соединениями и биогенами. При этом биообрастание может повысить иммобилизационную способность материалов для редоксзависимых металлов за счет ферментативных ресурсов бактериальных клеток, использующих их в качестве акцепторов электронов. Эффект микробного обрастания разнонаправленно изменял параметры материалов: для Cr в большинстве случаев уменьшение и для Cd значительное увеличение. При этом дополнительным эффектом иммобилизации Cr является его биологическое восстановление биопленками. Варьируя состав сорбционного материала, можно подбирать смеси, оптимально подходящие для очистки вод инфильтратов с полигонов твердых бытовых отходов с высокой нагрузкой по ХПК и биогенным элементам как при использовании in situ, так и в системах на поверхности.The analysis of the sorption characteristics of natural materials (vermiculite, expanded clay, perlite, Trade zeolite) during the purification of cadmium and chromium-containing leachate with a high COD load was carried out. It was determined that zeolite had the maximum sorption capacity for Cd and Cr and the lowest biological fouling. When using vermiculite and expanded clay or mixtures on their basis, one can expect an increase in the sorption capacity for Cd and Cr during microbial fouling that inevitably occurs during contacting with water polluted with organic compounds and nutrients. In this case biofouling can increase the immobilization properties of materials for redox-dependent metals due to the enzymatic resources of bacterial cells that use them as electron acceptors. The effect of microbial fouling changed the parameters of materials in different directions: for Cr, in most cases, downward, and for Cd, significantly upward. Moreover, chromium biological recovery by biofilms is an additional effect of immobilization. Varying the composition of the sorption material provides for selecting mixtures that are optimally suitable for the purification of leachates from solid waste landfills with high COD and nutrients load, both when used in situ and in surface systems.


2012 ◽  
Vol 20 (3) ◽  
pp. 303-309
Author(s):  
Ya-Juan LI ◽  
Cui-Hong YANG ◽  
Bo CHEN ◽  
Hui-Zhen QIU

2020 ◽  
Author(s):  
Chi-Toan Nguyen ◽  
Alistair Garner ◽  
Javier Romero ◽  
Antoine Ambard ◽  
Michael Preuss ◽  
...  

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