Using earth-tide induced water pressure changes to measure in situ permeability: A comparison with long-term pumping tests

The effective stress principle for soil is inspected by examining the original concept and derivation of the principle from the perspective of the ultra-soft soil engineering applications; and the existing problems of the principle were discussed in accordance with the general methodology of mechanics, and relative engineering phenomena observed. The changes of pore water pressure and soil pressure with time were obtained based on series of long term in-situ test in a large ultra-soft ground treatment works directed by the first author; and then an important conclusion has acquired from the test, i.e. the effective stress principle is not a self-contained principle and it’s related to the medium constitutive characteristics and loading action mode.

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Diagnosis of in Situ Air Sparging Performance Using Groundwater Pressure Changes During Startup and Shutdown

10.21236/ada406092 ◽

2001 ◽

Author(s):

Richard L. Johnson ◽

Paul C. Johnson ◽

Tim L. Johnson ◽

Neil Thomas ◽

Andrea Leason

Keyword(s):

Air Sparging ◽

Pressure Changes

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Global soil moisture data derived through machine learning trained with in-situ measurements

Scientific Data ◽

10.1038/s41597-021-00964-1 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Sungmin O. ◽

Rene Orth

Keyword(s):

Machine Learning ◽

Soil Moisture ◽

Large Scale ◽

Short Term Memory ◽

Temporal Dynamics ◽

Soil Moisture Data ◽

Wide Range ◽

Global Soil

AbstractWhile soil moisture information is essential for a wide range of hydrologic and climate applications, spatially-continuous soil moisture data is only available from satellite observations or model simulations. Here we present a global, long-term dataset of soil moisture derived through machine learning trained with in-situ measurements, SoMo.ml. We train a Long Short-Term Memory (LSTM) model to extrapolate daily soil moisture dynamics in space and in time, based on in-situ data collected from more than 1,000 stations across the globe. SoMo.ml provides multi-layer soil moisture data (0–10 cm, 10–30 cm, and 30–50 cm) at 0.25° spatial and daily temporal resolution over the period 2000–2019. The performance of the resulting dataset is evaluated through cross validation and inter-comparison with existing soil moisture datasets. SoMo.ml performs especially well in terms of temporal dynamics, making it particularly useful for applications requiring time-varying soil moisture, such as anomaly detection and memory analyses. SoMo.ml complements the existing suite of modelled and satellite-based datasets given its distinct derivation, to support large-scale hydrological, meteorological, and ecological analyses.

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Cutting Resistance Laboratory Testing Methodology for Underwater Coal Mining

Minerals ◽

10.3390/min11060564 ◽

2021 ◽

Vol 11 (6) ◽

pp. 564

Author(s):

Vladimir Čebašek ◽

Veljko Rupar ◽

Stevan Đenadić ◽

Filip Miletić

Keyword(s):

Coal Mining ◽

Laboratory Testing ◽

Water Pressure ◽

Laboratory Data ◽

Working Environment ◽

Laboratory Research ◽

Surrounding Water ◽

Cutting Resistance ◽

Testing Methodology

The bucket-wheel dredge “Kovin I” for underwater coal mining with bucket-wheel type UCW-450 has been in operation for over 20 years. Based on analyzing the bucket-wheel dredger performance, productivity, maintenance costs, and reliability, a rational decision was made: to rehabilitate the most essential parts of the dredge, including the bucket wheel and the gearbox. However, the selection and construction of the excavator parts were performed on the ground of available laboratory data for digging resistance. The data itself was determined by the testing methodology that did not include the influence of surrounding water pressure at a certain depth of mining. According to the previous findings, it was necessary to develop a specific research and testing program that would involve appropriate laboratory testing of the geomechanical parameters. These were to represent the influence of hydrostatic water pressure on the working environment—coal. Nevertheless, geomechanical laboratory research tests were initially modified to provide reliable data of cutting resistance, especially in the water under different hydrostatic pressures, fully simulating the “in situ” working conditions of mining, i.e., cutting.

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A Study of UVER in Santiago, Chile Based on Long-Term In Situ Measurements (Five Years) and Empirical Modelling

Energies ◽

10.3390/en14020368 ◽

2021 ◽

Vol 14 (2) ◽

pp. 368

Author(s):

Lisdelys González-Rodríguez ◽

Amauri Pereira de Oliveira ◽

Lien Rodríguez-López ◽

Jorge Rosas ◽

David Contreras ◽

...

Keyword(s):

Urban Areas ◽

Solar Spectrum ◽

Sun Exposure ◽

Great Accuracy ◽

In Situ Measurements ◽

Uv Index ◽

Empirical Modelling ◽

The People

Ultraviolet radiation is a highly energetic component of the solar spectrum that needs to be monitored because is harmful to life on Earth, especially in areas where the ozone layer has been depleted, like Chile. This work is the first to address the long-term (five-year) behaviour of ultraviolet erythemal radiation (UVER) in Santiago, Chile (33.5° S, 70.7° W, 500 m) using in situ measurements and empirical modelling. Observations indicate that to alert the people on the risks of UVER overexposure, it is necessary to use, in addition to the currently available UV index (UVI), three more erythema indices: standard erythemal doses (SEDs), minimum erythemal doses (MEDs), and sun exposure time (tery). The combination of UVI, SEDs, MEDs, and tery shows that in Santiago, individuals with skin types III and IV are exposed to harmfully high UVER doses for 46% of the time that UVI indicates is safe. Empirical models predicted hourly and daily values UVER in Santiago with great accuracy and can be applied to other Chilean urban areas with similar climate. This research inspires future advances in reconstructing large datasets to analyse the UVER in Central Chile, its trends, and its changes.

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In-Situ Annealed Ti3C2Tx MXene Based All-Solid-State Flexible Zn-Ion Hybrid Micro Supercapacitor Array with Enhanced Stability

Nano-Micro Letters ◽

10.1007/s40820-021-00634-2 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

La Li ◽

Weijia Liu ◽

Kai Jiang ◽

Di Chen ◽

Fengyu Qu ◽

...

Keyword(s):

High Energy ◽

High Rate ◽

High Energy Density ◽

Electrochemical Performances ◽

Integrated Electronics ◽

Long Term Stability ◽

Hybrid Supercapacitors ◽

Portable Electronics

AbstractZn-ion hybrid supercapacitors (SCs) are considered as promising energy storage owing to their high energy density compared to traditional SCs. How to realize the miniaturization, patterning, and flexibility of the Zn-ion SCs without affecting the electrochemical performances has special meanings for expanding their applications in wearable integrated electronics. Ti3C2Tx cathode with outstanding conductivity, unique lamellar structure and good mechanical flexibility has been demonstrated tremendous potential in the design of Zn-ion SCs, but achieving long cycling stability and high rate stability is still big challenges. Here, we proposed a facile laser writing approach to fabricate patterned Ti3C2Tx-based Zn-ion micro-supercapacitors (MSCs), followed by the in-situ anneal treatment of the assembled MSCs to improve the long-term stability, which exhibits 80% of the capacitance retention even after 50,000 charge/discharge cycles and superior rate stability. The influence of the cathode thickness on the electrochemical performance of the MSCs is also studied. When the thickness reaches 0.851 µm the maximum areal capacitance of 72.02 mF cm−2 at scan rate of 10 mV s−1, which is 1.77 times higher than that with a thickness of 0.329 µm (35.6 mF cm−2). Moreover, the fabricated Ti3C2Tx based Zn-ion MSCs have excellent flexibility, a digital timer can be driven by the single device even under bending state, a flexible LED displayer of “TiC” logo also can be easily lighted by the MSC arrays under twisting, crimping, and winding conditions, demonstrating the scalable fabrication and application of the fabricated MSCs in portable electronics.

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A long-term, gridded, subsurface physical oceanography dataset and average annual cycles derived from in situ measurements off the Western Australia coast during 2009–2020

Data in Brief ◽

10.1016/j.dib.2021.106812 ◽

2021 ◽

Vol 35 ◽

pp. 106812

Author(s):

Miaoju Chen ◽

Ming Feng

Keyword(s):

Western Australia ◽

In Situ Measurements ◽

Physical Oceanography ◽

Annual Cycles

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Poly(ethylene glycol)-b-poly(1,3-trimethylene carbonate) Copolymers for the Formulation of In Situ Forming Depot Long-Acting Injectables

Pharmaceutics ◽

10.3390/pharmaceutics13050605 ◽

2021 ◽

Vol 13 (5) ◽

pp. 605

Author(s):

Marie-Emérentienne Cagnon ◽

Silvio Curia ◽

Juliette Serindoux ◽

Jean-Manuel Cros ◽

Feifei Ng ◽

...

Keyword(s):

Ethylene Glycol ◽

Surface Erosion ◽

Sustained Delivery ◽

Trimethylene Carbonate ◽

Poly Ethylene Glycol ◽

In Situ Forming ◽

Poly Ethylene ◽

Long Acting

This article describes the utilization of (methoxy)poly(ethylene glycol)-b-poly(1,3-trimethylene carbonate) ((m)PEG–PTMC) diblock and triblock copolymers for the formulation of in situ forming depot long-acting injectables by solvent exchange. The results shown in this manuscript demonstrate that it is possible to achieve long-term drug deliveries from suspension formulations prepared with these copolymers, with release durations up to several months in vitro. The utilization of copolymers with different PEG and PTMC molecular weights affords to modulate the release profile and duration. A pharmacokinetic study in rats with meloxicam confirmed the feasibility of achieving at least 28 days of sustained delivery by using this technology while showing good local tolerability in the subcutaneous environment. The characterization of the depots at the end of the in vivo study suggests that the rapid phase exchange upon administration and the surface erosion of the resulting depots are driving the delivery kinetics from suspension formulations. Due to the widely accepted utilization of meloxicam as an analgesic drug for animal care, the results shown in this article are of special interest for the development of veterinary products aiming at a very long-term sustained delivery of this therapeutic molecule.

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