- Conference Article
- 10.7185/gold2023.16672
Anaerobic biodegradation of citric acid in the presence of cement pellets: Impact on cement integrity
- Jan 01, 2023
- Ananya Singh + 9 more +9
Publications from 2021 to 2026
Showing 10 of 31 papers
Anaerobic biodegradation of citric acid in the presence of cement pellets: Impact on cement integrity
Evaluation of Physical Properties of Leather on the Bating Process by Combination of Papain Enzyme with Surfactant
Bating is one of the important stages in the tanning process that has a role as a determinant of leather properties. It is commonly carried out with the assistance of protease enzymes such as papain. By using surfactants, sorbitol and Sodium Dodecyl Sulfate (SDS), it can help the penetration of enzymes into the skin or hides. Thereby, the study aimed to evaluate the use of papain on the bating process of kacang goat skin by assisted surfactants. Accordingly, three different concentrations (1, 1.5, & 2%) of enzymes were added with two different types of surfactants (SDS and Sorbitol) for the bating process. For the result, the leather was evaluated based on physical properties and histology studies. The presence of surfactant in the bating process improves the absorption of papain towards the hydrolysis of non-collagenous proteins. Based on the physical properties and histology studies, they perform better than leather without surfactant agents. Cleary, the surfactant agents can be used as bating auxiliary.
Read moreHigh-rate asymmetrical supercapacitors based on cobalt-doped birnessite nanotubes and Mn-FeOOH nanotubes.
Co-Doped MnO2 nanotubes (Co-MnO2-5) were prepared as the positive electrode of supercapacitors via a simple one-step hydrothermal method. Co doping and one-dimensional tunneling of nanotubes result in low internal resistance and good ionic contact, enhancing the conductivity and electrochemical performance of the electrodes.
Read moreBirnessite based nanostructures for supercapacitors: challenges, strategies and prospects
In the past few years, intensive attention has been focused on birnessite based electrodes for supercapacitors. Much progress has been achieved in developing birnessite based nanostructures with high electrochemical performance. However, challenges still remain in taking full advantage of birnessite and building smart structures to overcome the gap between the obtained capacitance and its theoretical capacitance. In this review, the basic information on birnessite and its preparation strategies are summarized and the current challenges are put forward. Finally, some new strategies for preparing high electrochemical performance birnessite based nanostructures are highlighted.
Read moreA Phenomenological Model for the Transport and Plugging of Aerosol through Stress Corrosion Cracks
Recent experimental evidence from Sandia (2018) demonstrated partial microchannel plugging due to particulate deposition. A direct consequence is that the accuracy of consequence assessments can be improved by accounting for the leak path deposition of aerosol in the source term. The filtration effect of microchannels, such as cracks, is relevant to the source term assessments. An important side effect of aerosol deposition in leak paths could be the plugging of the leak path. This report summarizes current progress (as of end of FY19) on the development of a phenomenological model of aerosol transport, deposition, and plugging through microchannels. The purpose is to introduce a generic, reliable numerical model for prediction of aerosol transport, deposition, and plugging in leak paths that are similar to stress corrosion cracks while accounting for potential plugging formation. This effort includes (i) development of a numerical model to analyze the various deposition processes in leak paths and provide quantitative estimates of penetration factors, as well as an understanding of the variables that affect them, (ii) confirmation of model validity with theoretical and experimental data, and (iii) parametric analysis for different scenarios including various particle sizes, pressures, and crack dimensions. Such a model could be used to improve the accuracy of consequence assessments and reduce the uncertainty of radiological consequence predictive analyses by taking the filtering effect of leak path aerosol deposition and plugging into account in the source term. This report includes: (i) an overview of main stress corrosion cracking characteristics, (ii) an overview of the developed numerical model to analyze the various deposition processes in leak paths, to provide quantitative estimates of penetration factors, and to gain an understanding of the variables that affect them, (iii) a summary of validation results and verification of the model’s validity with recent experimental results from Sandia and others, and (iv) a model application example.
Read moreIron coated peat as a sorbent for the simultaneous removal of arsenic and metals from contaminated water
This study aimed at combining peat, an industrial residue, with Fe(II)-Fe(III) compound to produce a sorbent suitable for a simultaneous removal of arsenic (As) and metals (cadmium, copper, nickel, lead, zinc) from a contaminated water. Using a newly produced sorbent – iron-peat – the removal of As from contaminated water was almost 17 times higher than using an uncoated peat. On the other hand, the removal of metals by the iron-peat was slightly less efficient in comparison to the uncoated peat. Simultaneous removal of As and metals could be seen as an advantage over multiple-step treatment of contaminated groundwater.
Read moreHow Will Autonomous Vehicles Change Local Government Budgeting and Finance? Case Studies of On-Street Parking, Curb Management, and Solid Waste Collection
This report is an examination of parking, curb zones, and government service changes in the context of AVs. Given that there are very few actual AVs on the road, the analysis in this report is an attempt to project what we might see, using the current phenomenon as starting points. The report uses a mix of econometric modeling, cost accounting, and case studies to illustrate these projections. The first section of this report looks at the effects of transportation network companies (TNCs)—Uber and Lyft in particular—on parking revenue in the city of Seattle. The results of the study indicate that TNCs are having a negative impact on parking. In the second section of the report, we look at curb space use and on-street parking occupancy levels. We again find that parking occupancy levels are being impacted by TNCs. And in the last section, I use cost accounting as a foundation for examining how the cost of government services may change over time when AVs replace drivers of government-owned vehicles. The particular case in this section looks at how AVs may change the cost curve for municipal trash collection.
Read morePreliminary study of tin slag concrete mixture
The study focuses on practices to facilitate tin smelting industry to reduce radioactive waste product (Tin Slag) by diluting its radioactivity to a safe level and turning it to a safer infrastructural building product. In the process the concrete mix which include Portland cement, sand, tin slag, water and plasticizer are used to produce interlocking brick pavements, piles and other infrastructural products. The mixing method follows DOE (UK) standard method of mixing targeted at in selected compressive strength suitable for its function and durability. A batching machine is used in the mixing and six test cubes are produced for the test. The testing equipment used are a compressional machine, ultrasonic measurement and a Geiger Muller counter to evaluate of the concrete mix to find the lowest emission of radiation surface dose without compromising the strength of concrete mix. The result obtained indicated the radioactivity of tin slag in the mixing process has reduced to background level that is 0.5μSv/h while the strength and workability of the concrete has not been severely affected. In conclusion, the concrete mix with tin slag has shown the potential it can be turned into a safe beneficial infrastructural product with good strength.
Read moreBentonite-supported nanoscale zero-valent iron granulated electrodes for industrial wastewater remediation
Bentonite-supported nanoscale zero-valent iron (B-nZVI) granulated electrodes were synthesized for remediation of pulp and paper wastewater as part of a three-dimensional (3D) electrode system.
Read moreNew Developments of an On-Vehicle Brake Pad Waste Collection System
<div class="section abstract"><div class="htmlview paragraph">The design of a braking system involves a delicate balance between the friction pair, the disc and pad, where the pad is a complex blend of constituents to provide predictable characteristics, typically, a known and consistent friction level. In its base form the brake has to absorb the vehicle kinetic energy by converting it into heat. This heat absorption by the friction pair can result in chemical and physical interactions with the release of debris about which we know little. Other than environmental concerns, brake dust causes unnecessary problems with wear, thermal gradients (hot banding) and NVH. This paper is concerned with the removal and collection of brake debris from the friction interface - the debris being regarded as solids and airborne particles, the latter less than 10μm in size. The test procedure consisted of a Burnish program followed by 8 different drive cycles. The overall effects of debris removal is then reported for each test. It will be shown that, by careful design of air circulation within a collection system, over 92% of dust generated may be removed and collected. It will also be shown that debris collection results in reduced rotor and pad wear and that the brake temperatures during the braking event are not significantly affected. The impact on brake cooling and brake operating temperatures during a customer usage-based braking schedule are under study. The implementation of providing a solution “at source” may provide the automotive industry with a system to meet current U.S. legislative requirements. It will also help to satisfy future costly global legislation. In addition the module will serve as a “real life” mobile laboratory where the OEMs may gather data from the filters to gain a greater understanding of the characteristics of the debris generated during braking - saving time and money on research. This is the first paper in a series which introduces the benefits of using the on-vehicle CBPModular brake wear debris collection system.</div></div>
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