An Autonomous Platform for Near Real-Time Surveillance of Harmful Algae and Their Toxins in Dynamic Coastal Shelf Environments

Efforts to identify in situ the mechanisms underpinning the response of harmful algae to climate change demand frequent observations in dynamic and often difficult to access marine and freshwater environments. Increasingly, resource managers and researchers are looking to fill this data gap using unmanned systems. In this study we integrated the Environmental Sample Processor (ESP) into an autonomous platform to provide near real-time surveillance of harmful algae and the toxin domoic acid on the Washington State continental shelf over a three-year period (2016–2018). The ESP mooring design accommodated the necessary subsystems to sustain ESP operations, supporting deployment durations of up to 7.5 weeks. The combination of ESP observations and a suite of contextual measurements from the ESP mooring and a nearby surface buoy permitted an investigation into toxic Pseudo-nitzschia spp. bloom dynamics. Preliminary findings suggest a connection between bloom formation and nutrient availability that is modulated by wind-forced coastal-trapped waves. In addition, high concentrations of Pseudo-nitzschia spp. and elevated levels of domoic acid observed at the ESP mooring location were not necessarily associated with the advection of water from known bloom initiation sites. Such insights, made possible by this autonomous technology, enable the formulation of testable hypotheses on climate-driven changes in HAB dynamics that can be investigated during future deployments.

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New Technologies for Decontamination of Radioactive Substances Scattered by Nuclear Accident / Nowe Technologie Dekontaminacji Radioaktywnych Substancji Rozproszonych Przez Awarie Nuklearna

Archives of Metallurgy and Materials ◽

10.2478/v10172-012-0186-1 ◽

2013 ◽

Vol 58 (1) ◽

pp. 283-290 ◽

Cited By ~ 4

Author(s):

Y. Nishizaki ◽

H. Miyamae ◽

S. Ichikawa ◽

K. Izumiya ◽

T. Takano ◽

...

Keyword(s):

Radioactive Waste ◽

New Technologies ◽

Ferric Hydroxide ◽

Nuclear Accident ◽

Radioactive Cesium ◽

Cesium Ions ◽

Naoh Solution ◽

High Concentrations ◽

Water Rinsing

Our effort for decontamination of radioactive cesium scattered widely by nuclear accident in March 2011 in Fukushima, Japan has been described. Radioactive cesium scattered widely in Japan has been accumulating in arc or plasma molten-solidified ash in waste incinerating facilities up to 90,000 Bq/kg of the radioactive waste. Water rinsing of the ash resulted in dissolution of cesium ions together with high concentrations of potassium and sodium ions. Although potassium inhibits the adsorption of cesium on zeolite, we succeeded to precipitate cesium by in-situ formation of ferric ferrocyanide and iron rust in the radioactive filtrate after rinsing of the radioactive ash with water. Because the regulation of no preservation of any kind of cyanide substances, cesium was separated from the precipitate consisting of cesium-captured ferric ferrocyanide and ferric hydroxide in diluted NaOH solution and subsequent filtration gave rise to the potassium-free radioactive filtrate. Cesium was captured by zeolite from the potassium-free radioactive filtrate. The amount of this final radioactive waste of zeolite was significantly lower than that of the arc-molten-solidified ash.

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Probing the Dynamic Self-Assembly Behaviour of Photoswitchable Wormlike Micelles in Real Time

10.26434/chemrxiv.7098695 ◽

2018 ◽

Author(s):

Elaine A. Kelly ◽

Judith E. Houston ◽

Rachel Evans

Keyword(s):

Real Time ◽

Absorption Spectroscopy ◽

Self Assembly ◽

Uv Light ◽

Wormlike Micelles ◽

Tetraethylene Glycol ◽

Light Illumination ◽

First Time ◽

Dependent Processes

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such asdrug delivery and micellar catalysis. Currently, their behaviour in the equilibrium cis-and trans-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, <a>tetraethylene glycol mono(4′,4-octyloxy,octyl-azobenzene) </a>(C8AzoOC8E4) using small-angle neutron scattering (SANS). We show that the incorporation of in-situUV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C8AzoOC8E4could switch between wormlike micelles (transnative state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked in-situthrough combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly.

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Flat Flexible Thin Milli-electrode Array for Real-time in situ Water Quality Monitoring in Distribution Systems

Proceedings of the Water Environment Federation ◽

10.2175/193864717822157432 ◽

2017 ◽

Vol 2017 (4) ◽

pp. 5598-5617

Author(s):

Zhiheng Xu ◽

Wangchi Zhou ◽

Qiuchen Dong ◽

Yan Li ◽

Dingyi Cai ◽

...

Keyword(s):

Water Quality ◽

Real Time ◽

Distribution Systems ◽

Electrode Array ◽

Water Quality Monitoring ◽

Quality Monitoring

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Real-time monitoring of high-gravity corn mash fermentation using in situ raman spectroscopy

Biotechnology and Bioengineering ◽

10.1002/bit.24849 ◽

2013 ◽

Vol 110 (6) ◽

pp. 1654-1662 ◽

Cited By ~ 18

Author(s):

Steven R. Gray ◽

Steven W. Peretti ◽

H. Henry Lamb

Keyword(s):

Raman Spectroscopy ◽

Real Time ◽

High Gravity ◽

Real Time Monitoring ◽

In Situ Raman Spectroscopy ◽

In Situ Raman ◽

Corn Mash

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Real-time in situ visualization of internal relative humidity in fluorescence embedded cement-based materials

Journal of Central South University ◽

10.1007/s11771-021-4666-1 ◽

2021 ◽

Author(s):

Hai-tao Gu ◽

Zheng-hong Yang ◽

Zhen Fan ◽

Wei Jiang

Keyword(s):

Relative Humidity ◽

Real Time ◽

Cement Based Materials ◽

In Situ Visualization ◽

Internal Relative Humidity

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Underground Microseismic Event Monitoring and Localization within Sensor Networks

Sensors ◽

10.3390/s21082830 ◽

2021 ◽

Vol 21 (8) ◽

pp. 2830

Author(s):

Sili Wang ◽

Mark P. Panning ◽

Steven D. Vance ◽

Wenzhan Song

Keyword(s):

Sensor Networks ◽

Real Time ◽

Information Needs ◽

Localization Algorithm ◽

Distributed Sensors ◽

Distributed Sensor ◽

Microseismic Events ◽

The Stability ◽

Stability And Accuracy

Locating underground microseismic events is important for monitoring subsurface activity and understanding the planetary subsurface evolution. Due to bandwidth limitations, especially in applications involving planetarily-distributed sensor networks, networks should be designed to perform the localization algorithm in-situ, so that only the source location information needs to be sent out, not the raw data. In this paper, we propose a decentralized Gaussian beam time-reverse imaging (GB-TRI) algorithm that can be incorporated to the distributed sensors to detect and locate underground microseismic events with reduced usage of computational resources and communication bandwidth of the network. After the in-situ distributed computation, the final real-time location result is generated and delivered. We used a real-time simulation platform to test the performance of the system. We also evaluated the stability and accuracy of our proposed GB-TRI localization algorithm using extensive experiments and tests.

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In situ, real-time measurements of contact pressure internal to jointed interfaces during dynamic excitation of an assembled structure

Mechanical Systems and Signal Processing ◽

10.1016/j.ymssp.2021.107859 ◽

2021 ◽

Vol 160 ◽

pp. 107859

Author(s):

T. Dreher ◽

M.R.W. Brake ◽

B. Seeger ◽

M. Krack

Keyword(s):

Real Time ◽

Contact Pressure ◽

Dynamic Excitation

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Fe3O4@C Nanoparticles Synthesized by In Situ Solid-Phase Method for Removal of Methylene Blue

Nanomaterials ◽

10.3390/nano11020330 ◽

2021 ◽

Vol 11 (2) ◽

pp. 330

Author(s):

Hengli Xiang ◽

Genkuan Ren ◽

Yanjun Zhong ◽

Dehua Xu ◽

Zhiye Zhang ◽

...

Keyword(s):

Methylene Blue ◽

Solid Phase ◽

Raw Materials ◽

Phase Method ◽

Maximum Adsorption Capacity ◽

High Catalytic Activity ◽

Solid Phase Reaction ◽

Phase Reaction ◽

High Concentrations

Fe3O4@C nanoparticles were prepared by an in situ, solid-phase reaction, without any precursor, using FeSO4, FeS2, and PVP K30 as raw materials. The nanoparticles were utilized to decolorize high concentrations methylene blue (MB). The results indicated that the maximum adsorption capacity of the Fe3O4@C nanoparticles was 18.52 mg/g, and that the adsorption process was exothermic. Additionally, by employing H2O2 as the initiator of a Fenton-like reaction, the removal efficiency of 100 mg/L MB reached ~99% with Fe3O4@C nanoparticles, while that of MB was only ~34% using pure Fe3O4 nanoparticles. The mechanism of H2O2 activated on the Fe3O4@C nanoparticles and the possible degradation pathways of MB are discussed. The Fe3O4@C nanoparticles retained high catalytic activity after five usage cycles. This work describes a facile method for producing Fe3O4@C nanoparticles with excellent catalytic reactivity, and therefore, represents a promising approach for the industrial production of Fe3O4@C nanoparticles for the treatment of high concentrations of dyes in wastewater.

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