Microbially induced calcite precipitation performance of multiple landfill indigenous bacteria compared to a commercially available bacteria in porous media

Microbially Induced Carbonate Precipitation (MICP) is currently viewed as one of the potential prominent processes for field applications towards the prevention of soil erosion, healing cracks in bricks, and groundwater contamination. Typically, the bacteria involved in MICP manipulate their environment leading to calcite precipitation with an enzyme such as urease, causing calcite crystals to form on the surface of grains forming cementation bonds between particles that help in reducing soil permeability and increase overall compressive strength. In this paper, the main focus is to study the MICP performance of three indigenous landfill bacteria against a well-known commercially bought MICP bacteria (Bacillus megaterium) using sand columns. In order to check the viability of the method for potential field conditions, the tests were carried out at slightly less favourable environmental conditions, i.e., at temperatures between 15-17°C and without the addition of urease enzymes. Furthermore, the sand was loose without any compaction to imitate real ground conditions. The results showed that the indigenous bacteria yielded similar permeability reduction (4.79 E-05 to 5.65 E-05) and calcium carbonate formation (14.4–14.7%) to the control bacteria (Bacillus megaterium), which had permeability reduction of 4.56 E-5 and CaCO3 of 13.6%. Also, reasonably good unconfined compressive strengths (160–258 kPa) were noted for the indigenous bacteria samples (160 kPa). SEM and XRD showed the variation of biocrystals formation mainly detected as Calcite and Vaterite. Overall, all of the indigenous bacteria performed slightly better than the control bacteria in strength, permeability, and CaCO3 precipitation. In retrospect, this study provides clear evidence that the indigenous bacteria in such environments can provide similar calcite precipitation potential as well-documented bacteria from cell culture banks. Hence, the idea of MICP field application through biostimulation of indigenous bacteria rather than bioaugmentation can become a reality in the near future.

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Theoretical challenges for flavor physics

The European Physical Journal Plus ◽

10.1140/epjp/s13360-021-01845-7 ◽

2021 ◽

Vol 136 (9) ◽

Author(s):

Yuval Grossman ◽

Zoltan Ligeti

Keyword(s):

Standard Model ◽

Flavor Physics ◽

Beyond The Standard Model ◽

Physics Program ◽

The Standard Model ◽

Nonperturbative Qcd ◽

Near Future ◽

Better Than

AbstractWe discuss some highlights of the FCC-$$ee$$ ee flavor physics program. It will help to explore various aspects of flavor physics: to test precision calculations, to probe nonperturbative QCD methods, and to increase the sensitivity to physics beyond the standard model. In some areas, FCC-$$ee$$ ee will do much better than current and near-future experiments. We briefly discuss several probes that can be relevant for maximizing the gain from the FCC-$$ee$$ ee flavor program.

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Permeability Improvement Technology of Directional Hydraulic Fracturing in Low Permeability

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.599-601.385 ◽

2014 ◽

Vol 599-601 ◽

pp. 385-390 ◽

Cited By ~ 1

Author(s):

Xue Xi Chen ◽

Rui Qing Bi ◽

Wen Guang Jin ◽

Yong Xu

Keyword(s):

Stress Concentration ◽

Hydraulic Fracturing ◽

Maximum Concentration ◽

Local Stress ◽

Field Application ◽

Low Permeability ◽

Pressure Relief ◽

Local Stress Concentration ◽

Directional Hydraulic Fracturing ◽

Better Than

According to the conventional fracturing could easily lead to the local stress concentration of coal, the effect of pressure relief and permeability improvement is not ideal. The mechanism of directional hydraulic fracturing is analyzed and the parameters such as the layout of directional hole, the fracturing hole sealing, the minimum cracking pressure are discussed, then the field application tests are carried out. The results show that the directional hydraulic fracturing effect is better than that of ordinary fracturing hole and the maximum concentration and the average drainage scalar is respectively 3.75 times and 4 times of the ordinary hole pumping gas fracturing effects. The effect of permeability improvement is remarkable.

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Production of phosphorus biofertilizer based on the renewable materials in large laboratory scale

Open Chemistry ◽

10.1515/chem-2019-0057 ◽

2019 ◽

Vol 17 (1) ◽

pp. 893-901 ◽

Cited By ~ 2

Author(s):

Małgorzata Wyciszkiewicz ◽

Marcin Sojka ◽

Agnieszka Saeid

Keyword(s):

Bacillus Megaterium ◽

Large Scale ◽

Biomass Concentration ◽

Scaling Up ◽

Phosphorus Concentration ◽

Available Phosphorus ◽

Direct Influence ◽

Renewable Materials ◽

P Fertilizers ◽

Better Than

AbstractThis paper discusses the effect of the utilization of Bacillus megaterium in the microbial solubilization process where poultry bones or ash were used as a source of renewable phosphorus. The process was performed in a large scale laboratory. The pH of the solution decreased during one-week solubilization, which had a direct influence on the increased concentration of phosphorus determined in the solution. It was proved that the phosphorus concentration in the solution was significantly correlated with the biomass concentration and pH. The trial allowed verification of the suitability of the method to prepare two P fertilizers: one based on poultry bones and one on ashes. The elemental analysis of their composition suggests that the bones are a P-bearing resource with properties better than ash. That enables for more efficient scaling-up the solubilization although the concentration of total phosphorus was comparable in both cases. The total amount (100%) of phosphorus was present in a form available to plants in the formulation based on the poultry bones, while 64% of plant available phosphorus was present in the formulation based on the ash. The concentration of Cd was significantly lower in the case of fertilizer based on bones with respect to ash.

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Assessment and Development of Bone Preparation for Radiocarbon Dating at HEKAL

Radiocarbon ◽

10.1017/rdc.2019.60 ◽

2019 ◽

Vol 61 (5) ◽

pp. 1551-1561 ◽

Cited By ~ 1

Author(s):

István Major ◽

István Futó ◽

János Dani ◽

Orsolya Cserpák-Laczi ◽

Mihály Gasparik ◽

...

Keyword(s):

Uncertainty Range ◽

Bone Measurement ◽

Test Study ◽

C Value ◽

The Mean ◽

Materials Used ◽

Near Future ◽

Preparation Techniques ◽

Small Bone ◽

Better Than

ABSTRACTBone is one of the most complex sample materials used for radiocarbon (14C) dating. The installation of the EnvironMICADAS AMS at HEKAL (department of ICER) in 2011 required the adoption of new sample preparation techniques for small bone samples. Since then, hundreds of procedural background and known-age bones have been processed using our modified Longin method (MLM) and dated along with unknown samples. Their results are used in this study to assess the reproducibility of our current bone preparation method and the real uncertainty of the final age result. In addition, using the background samples, which are included in each bone measurement batch, blank correction of the unknown samples could also be performed. The mean F14C value of our bone blanks is generally better than 0.005 (∼42,500 BP) alongside 0.0013 SD. Good reproducibility was confirmed by the results of the laboratory known-age bone as well, where the standard deviation of the mean is better than 0.0025. In addition, the results of the three bone samples used in an ultrafiltration (UF) test study did not show notable differences from the ones obtained by our current protocol in 1σ uncertainty range but more experiments will be performed in the near future.

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Chinese Outward Foreign Direct Investment

International Journal of Asian Business and Information Management ◽

10.4018/jabim.2010100104 ◽

2010 ◽

Vol 1 (4) ◽

pp. 43-56 ◽

Cited By ~ 1

Author(s):

Fernanda Ilhéu

Keyword(s):

Foreign Aid ◽

Social Security Systems ◽

Security Systems ◽

Gdp Growth Rate ◽

Short And Long Term ◽

Economic Imbalances ◽

Sustainable Economic Growth ◽

Near Future ◽

Better Than

In past years, China recorded a fast sustainable economic growth with an estimated average GDP growth rate of 9.7% in the period of 1980-2008, turning China into the world’s second largest economy. With an export oriented economic model, China is the most attractive developing country for FDI flows, both short and long term. In this regard, China has been able to achieve a foreign exchange reserve of US$ 2.2 trillion, the world´s largest reserve currency. Around 50% of this huge reserve is being applied in American bonds, while the remaining supports Chinese health and social security systems, bank solvability, internationalization of their economy, investment in geostrategic positioning, and making foreign aid available to other developing countries. During the 2008 global crisis, China was able to resist better than other major world economies, benefitting from this downturn to implement policies to reduce its economic imbalances. One of these imbalances is the gap between Chinese FDI and OFDI, which is now progressively narrowing. In the near future, OFDI is expected to be larger than FDI, and in this paper, the authors research whether Chinese OFDI can be explained by existing theories or if a new theory is required.

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Godin Lake Trial: X120 Field Welding

Volume 3: Materials and Joining; Pipeline Automation and Measurement; Risk and Reliability, Parts A and B ◽

10.1115/ipc2006-10397 ◽

2006 ◽

Author(s):

Nicholas E. Biery ◽

Mario L. Macia ◽

Robert J. T. Appleby ◽

Doug P. Fairchild ◽

Doug S. Hoyt ◽

...

Keyword(s):

Field Application ◽

Destructive Testing ◽

Weld Repair ◽

Well Productivity ◽

Better Than ◽

Made In

In February 2004, ExxonMobil and TransCanada PipeLines, Limited (TCPL) cooperated to construct a 1.6 km long segment of X120 pipeline near Wabasca, Alberta. The line included numerous mainline and tie-in welds, and an extra section of pipe was constructed in the field for later destructive testing to assess the characteristics of field welds. This line represented the first field application of welding procedures and consumables developed specifically for X120. The technologies used performed well; productivity and weld repair rates were better than expected, and the properties of these welds made in challenging conditions compare well with development welds made under controlled “shop” conditions.

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Kinetics of urease mediated calcite precipitation and permeability reduction of porous media evidenced by magnetic resonance imaging

International Journal of Environmental Science and Technology ◽

10.1007/s13762-013-0241-0 ◽

2013 ◽

Vol 10 (5) ◽

pp. 881-890 ◽

Cited By ~ 16

Author(s):

S. Handley-Sidhu ◽

E. Sham ◽

M. O. Cuthbert ◽

S. Nougarol ◽

M. Mantle ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Porous Media ◽

Magnetic Resonance ◽

Permeability Reduction ◽

Resonance Imaging ◽

Calcite Precipitation ◽

Kinetics Of

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The IFAE/UAB Raman LIDAR for the CTA-North

EPJ Web of Conferences ◽

10.1051/epjconf/201919702005 ◽

2019 ◽

Vol 197 ◽

pp. 02005

Author(s):

Markus Gaug ◽

Oscar Blanch ◽

Merve Sıdıka Çolak ◽

Michele Doro ◽

Lluis Font ◽

...

Keyword(s):

Focal Plane ◽

Light Guide ◽

Aerosol Extinction ◽

Raman Lidar ◽

Readout System ◽

The Status ◽

One Year ◽

Near Future ◽

532 Nm ◽

Better Than

The IFAE/UAB Raman LIDAR project aims to develop a Raman LIDAR suitable for the online atmospheric calibration of the CTA. Requirements for such a solution include the ability to characterize aerosol extinction to distances of more than 20 km with an accuracy better than 5%, within time scales of less than one minute. The Raman LIDAR consists therefore of a large 1.8 m mirror and a powerful pulsed Nd-YAG laser. A liquid light-guide collects the light at the focal plane and transports it to the readout system. An in-house built polychromator has been characterized thoroughly with respect to its capability to separate effciently the different wavelengths (355 nm, 387 nm, 532 nm and 607 nm). It was found to operate according to specifications, particularly that light leakage from the elastic channels (532 nm and 355 nm) into the much dimmer Raman channels (387 nm and 607 nm) could be excluded to less than 2 × 10-7. We present here the status of the integration and commissioning of this solution and plans for the near future. After a one-year test period at the Observatorio del Roque de los Muchachos, an in-depth evaluation of this and the solutions adopted by a similar project developed by the LUPM, Montpellier, will lead to a final Raman LIDAR proposed to be built for both CTA sites.

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Can redshift errors bias measurements of the Hubble Constant?

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2652 ◽

2019 ◽

Vol 490 (2) ◽

pp. 2948-2957 ◽

Cited By ~ 12

Author(s):

Tamara M Davis ◽

Samuel R Hinton ◽

Cullan Howlett ◽

Josh Calcino

Keyword(s):

Cosmological Parameters ◽

Hubble Constant ◽

Vertical Axis ◽

Limiting Factor ◽

Cosmological Redshift ◽

Physical Effects ◽

Observational Errors ◽

Near Future ◽

Exhaustive List ◽

Better Than

ABSTRACT Redshifts have been so easy to measure for so long that we tend to neglect the fact that they too have uncertainties and are susceptible to systematic error. As we strive to measure cosmological parameters to better than 1 per cent it is worth reviewing the accuracy of our redshift measurements. Surprisingly small systematic redshift errors, as low as 10−4, can have a significant impact on the cosmological parameters we infer, such as H0. Here, we investigate an extensive (but not exhaustive) list of ways in which redshift estimation can go systematically astray. We review common theoretical errors, such as adding redshifts instead of multiplying by (1 + z); using v = cz; and using only cosmological redshift in the estimates of luminosity and angular diameter distances. We consider potential observational errors, such as rest wavelength precision, air to vacuum conversion, and spectrograph wavelength calibration. Finally, we explore physical effects, such as peculiar velocity corrections, galaxy internal velocities, gravitational redshifts, and overcorrecting within a bulk flow. We conclude that it would be quite easy for small systematic redshift errors to have infiltrated our data and be impacting our cosmological results. While it is unlikely that these errors are large enough to resolve the current H0 tension, it remains possible, and redshift accuracy may become a limiting factor in near future experiments. With the enormous efforts going into calibrating the vertical axis of our plots (standard candles, rulers, clocks, and sirens) we argue that it is now worth paying a little more attention to the horizontal axis (redshifts).

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