scholarly journals Technical note: Assessing gas equilibration systems for continuous <i>p</i>CO<sub>2</sub> measurements in inland waters

2016 ◽  
Vol 13 (13) ◽  
pp. 3915-3930 ◽  
Author(s):  
Tae Kyung Yoon ◽  
Hyojin Jin ◽  
Neung-Hwan Oh ◽  
Ji-Hyung Park
Keyword(s):  
River System ◽  
Fast Response ◽  
Technical Note ◽  
Spatial Variations ◽  
Detection Range ◽  
Measurement Systems ◽  
Co2 Sensor ◽  
Continuous Measurements ◽  
Membrane Biofouling

Abstract. High-frequency continuous measurements of the partial pressure of CO2 (pCO2) are crucial for constraining the spatiotemporal dynamics of CO2 emissions from inland water systems. However, direct measurements of pCO2 are scarce, and no systematic comparisons have been conducted on the suitability of the widely used measurement systems for continuous underway or long-term deployment in various field conditions. We compared spray- and marble-type equilibrators and a membrane-enclosed CO2 sensor to assess their suitability for continuous long-term or underway pCO2 measurements in an urbanized river system in Korea. Both equilibrators had a shorter response time compared with the membrane-enclosed sensor, and could capture large spatial variations of pCO2 during a transect study along a highly urbanized river reach. The membrane-enclosed sensor based on passive equilibration provided comparable underway measurements along the river sections where pCO2 varied within the sensor detection range. When deployed in a eutrophic river site, the membrane-enclosed sensor was able to detect large diel variations in pCO2. However, biofouling on the membrane could reduce the accuracy of the measurement during long deployments exceeding several days. The overall results suggest that the fast response of the equilibrator systems facilitates capturing large spatial variations in pCO2 during short underway measurements. However, the attendant technical challenges of these systems, such as clogging and desiccant maintenance, have to be addressed carefully to enable their long-term deployment. The membrane-enclosed sensor would be suitable as an alternative tool for long-term continuous measurements if membrane biofouling could be overcome by appropriate antifouling measures such as copper mesh coverings.

scholarly journals Technical note: Applying equilibration systems to continuous measurements of <i>p</i>CO<sub>2</sub> in inland waters

2016 ◽  
Author(s):  
T. K. Yoon ◽  
H. Jin ◽  
N.-H. Oh ◽  
J.-H. Park
Keyword(s):  
Field Tests ◽  
River System ◽  
Temporal Variations ◽  
Technical Note ◽  
Detection Range ◽  
Measurement Systems ◽  
Continuous Measurements ◽  
Application Potential ◽  
River Reach

Abstract. High-frequency measurements of the partial pressure of CO2 (pCO2) are crucial in elucidating spatiotemporal dynamics of CO2 evasion from inland water systems and their role in the global carbon cycle. However, direct measurements of pCO2 are scarce, and the currently used measurement systems have not been compared for long-term deployment under various field conditions. A literature review was combined with laboratory and field tests to evaluate the application potential of three widely used automated equilibration systems, including spray- and marble-type equilibrators and a membrane-enclosed CO2 sensor, to continuous long-term or underway pCO2 measurements in an urbanized river system in Korea. Both equilibrators had a shorter response time than the membrane-enclosed sensor, well capturing large spatial variations of pCO2 during a transect study along a highly urbanized river reach. The membrane-enclosed sensor based on passive equilibration provided comparable underway measurements for the same river reach until pCO2 approached the upper detection limit of the sensor. The membrane-enclosed sensor deployed in a eutrophic river site could detect large temporal variations of pCO2 over several weeks. To tackle biofouling on the membrane that can reduce sensor accuracy over time, we suggest that antifouling measures, such as copper-mesh screening, be used for long-term deployments with maintenance intervals ranging from several days to weeks. The overall results suggest that the equilibrators are better suited for relatively short underway measurements than long-term deployment, whereas the membrane-enclosed sensor can be used for both the underway and long-term continuous measurements if the sensor has a proper detection range and can be protected by a biofouling-resistant covering.

Basic principles for assessing the safety of fish products from the ponds exposed to the influence of nuclear fuel cycle enterprises

2019 ◽  
pp. 106-114
Author(s):  
A. V. Trapeznikov ◽  
V. N. Trapeznikova ◽  
A. V. Korzhavin ◽  
V. N. Nikolkin ◽  
A. P. Plataev
Keyword(s):  
Fuel Cycle ◽  
Specific Activity ◽  
River System ◽  
Food Product ◽  
Human Consumption ◽  
Basic Principles ◽  
Fish Products ◽  
Permissible Levels ◽  
Irtysh River

Relevance. In connection with the development of nuclear energy, many aquatic ecosystems have been exposed to radioactive substances. Fish, as an element of biota, is capable to accumulate radionuclides. However, fish is a traditional food. The control of the technogenic radionuclides accumulation level in the ichthyofauna is an important link in ensuring human security.Intention. To analyze the long-term data on the content of long-lived technogenic radionuclides 90Sr and 137Cs in the ichthyofauna of the Ob-Irtysh river system for the period from 2004 to 2016 and Beloyarsky pond for the period from 1977 to 2018.Methodology. Fish as a food product was assessed according to two criteria: a) permissible levels of specific activity of radionuclides (SanPiN 2.3.2.1078-01); b) using the indicator of conformity B and the uncertainty of its definition В (GOST 32161-2013 and GOST 32163-2013).Results and Discussion. Fish of all species that live in the river Tetcha, is not suitable for food use according to the criteria of SanPiN 2.3.2.1078-01, GOST 32161-2013 and GOST 32163-2013. The fish of the Ob-Irtysh river system, the habitat of which is located outside the Tetcha, meets the requirements for fish products. In the period from 1977 to 1989 in the Beloyarsk pond the accumulations of technogenic radionuclides in fish in quantities exceeding sanitary and hygienic standards were possible. Currently, the fish of the Beloyarsky pond fully complies with the sanitary and hygienic requirements for the radiation factor and is safe for human consumption.Conclusion. In the ponds exposed to the atomic energy enterprises, it is necessary to continuously monitor the content of long-lived technogenic radionuclides in fish and assess their amount in accordance with the requirements of SanPiN 2.3.2.1078-01 and using the conformity indicator В and the uncertainty of its determination В. 

River Quality Models for Consent Setting in England and Wales

1989 ◽  
Vol 21 (8-9) ◽  
pp. 1015-1024 ◽  
Author(s):  
C. P. Crockett ◽  
R. W. Crabtree ◽  
I. D. Cluckie
Keyword(s):  
River System ◽  
Quality Model ◽  
Catchment Scale ◽  
Quality Models ◽  
England And Wales ◽  
Future Developments ◽  
Statistical Framework ◽  
River Quality ◽  
National Approach

In England and Wales the placing of effluent discharge consents within a statistical framework has led to the development of a new hybrid type of river quality model. Such catchment scale consent models have a stochastic component for the generation of model inputs and a deterministic component to route them through the river system. This paper reviews and compares the existing approaches for consent modelling used by various Water Authorities. A number of possible future developments are suggested including the potential need for a national approach to the review and setting of long term consents.

High-performance humidity sensors from Ni(SO4)0.3(OH)1.4 nanobelts

Nanoscale ◽  
2014 ◽  
Vol 6 (12) ◽  
pp. 6521-6525 ◽  
Author(s):  
Ming Zhuo ◽  
Yuejiao Chen ◽  
Tao Fu ◽  
Haonan Zhang ◽  
Zhi Xu ◽  
...  
Keyword(s):  
High Performance ◽  
Humidity Sensor ◽  
High Sensitivity ◽  
Fast Response ◽  
Humidity Sensors ◽  
Term Stability ◽  
Long Term Stability

Ni(SO4)0.3(OH)1.4 nanobelts are utilized in a humidity sensor by a facile method. The nanobelt based sensor shows a high sensitivity, fast response and long-term stability in the sensing process.

scholarly journals Long-term spatial variations in the Baltic Sea wave fields

Ocean Science ◽  
2011 ◽  
Vol 7 (1) ◽  
pp. 141-150 ◽  
Author(s):  
T. Soomere ◽  
A. Räämet
Keyword(s):  
Baltic Sea ◽  
Spatial Variations ◽  
Extreme Wave ◽  
The Baltic Sea ◽  
Wave Fields ◽  
Wave Heights ◽  
The Baltic ◽  
Wave Properties ◽  
Sea Wave

Abstract. This study focuses on spatial patterns in linear trends of numerically reconstructed basic wave properties (average and extreme wave heights, wave periods) in the Baltic Sea under the assumption of no ice cover. Numerical simulations of wave conditions for 1970–2007, using the WAM wave model and adjusted geostrophic winds, revealed extensive spatial variations in long-term changes in both average and extreme wave heights in the Baltic Sea but almost no changes in the basinwide wave activity and wave periods. There has been a statistically significant decrease in the annual mean significant wave height by more than 10% between the islands of Öland and Gotland and in the southward sea area, and a substantial increase to the south-west of Bornholm, near the coast of Latvia, between the Åland Archipelago and the Swedish mainland, and between the Bothnian Sea and the Bothnian Bay. Variations in extreme wave heights (defined as the threshold for 1% of the highest waves each year) show similar patterns of changes. In several areas the trends in average and extreme wave heights are different. Such a complicated pattern of changes indicates that (i) different regions of the Baltic Sea basin have experienced widespread but essentially different changes in wind properties and (ii) many seemingly controversial trends and variations established in wave properties at different sites in the recent past may reflect the natural spatial variability in the Baltic Sea wave fields.

scholarly journals Technical note: GUARD – An automated fluid sampler preventing sample alteration by contamination, evaporation and gas exchange, suitable for remote areas and harsh conditions

2018 ◽  
Author(s):  
Arno Hartmann ◽  
Marc Luetscher ◽  
Ralf Wachter ◽  
Philipp Holz ◽  
Elisabeth Eiche ◽  
...  
Keyword(s):  
Gas Exchange ◽  
Field Experiments ◽  
Hydrological Cycle ◽  
Technical Note ◽  
Production Costs ◽  
Environmental Research ◽  
Remote Areas ◽  
Wide Range ◽  
Public And Private Sector

Abstract. Automated water sampling devices adapted to field operation have proven highly useful for environmental research as well as in the public and private sector, where natural or artificial waters need to be tested regularly for compliance with environmental and health regulations. Such autosamplers are already available on the market in slightly differing versions, but none of these devices are capable of sealing the collected samples to prevent sample alteration by contamination, evaporation or gas exchange. In many sampling cases, however, this feature is essential, for instance for studying the hydrological cycle based on isotopes in rainwater, or for monitoring waters contaminated with toxic gases or other volatile compounds detrimental to biota and human health. Therefore, we have developed a new mobile autosampler, which injects water samples directly into airtight vials, thus preventing any sample alteration. Further advantages include low production costs, compact dimensions and low weight allowing for easy transport, a wide range of selectable sampling intervals as well as a low power consumption, which make it suitable for long-term applications even in remote areas and harsh (outdoor) conditions due to its heavy-duty water-proof casing. In this paper, we demonstrate (1) the sampler's mechanical functioning, (2) the long-term stability of the collected samples with regard to evaporation and gas exchange and (3) the potential of our device in a wide variety of applications drawing on laboratory and field experiments in different karst caves, which represent one of the most challenging sampling environments.

scholarly journals PETA RENCANA (ROADMAP) RISET ENTERPRISE RESOURCE PLANNING (ERP) DENGAN FOKUS RISET PADA USAHA KECIL DAN MENENGAH (UKM) DI INDONESIA

2012 ◽  
Vol 6 (2) ◽  
pp. 140
Author(s):  
Putu Wuri Handayani ◽  
J.W. Saputro ◽  
Achmad Nizar Hidayanto ◽  
Indra Budi
Keyword(s):  
Enterprise Resource Planning ◽  
Business Processes ◽  
Small And Medium Enterprises ◽  
Resource Planning ◽  
Fast Response ◽  
National Data ◽  
Critical Issues ◽  
The Republic ◽  
Medium Enterprises

Usaha Kecil dan Menengah (UKM) di Indonesia telah dapat berkontribusi terhadap PDB (Produk Domestik Bruto) nasional sebesar 55.56% berdasarkan data Biro Perencanaan Kementerian Negara Koperasi dan UKM Republik Indonesia, pada tahun 2008. Untuk memperluas pangsa pasar dan meningkatkan daya saing UKM, UKM membutuhkan suatu aplikasi yang dapat mengintegrasikan dan mengotomatisasi proses bisnis UKM. Aplikasi ERP dapat menjadi salah satu solusi untuk UKM dikarenakan keuntungan yang dapat diberikan seperti memberikan informasi dengan waktu respon yang cepat, meningkatkan interaksi antar bagian dalam suatu organisasi, meningkatkan pengelolaan siklus pemesanan barang, dsb. Beberapa isu kritis yang dihadapi oleh UKM adalah terbatasnya dana dan kapabilitas teknologi informasi yang dimiliki. Dalam memahami kebutuhan layanan yang diperlukan oleh UKM untuk aplikasi ERP dan untuk menyediakan arahan bagi UKM serta menanggapi kurangnya riset ERP di Indonesia maka riset ini bertujuan untuk menggambarkan peta rencana jangka panjang dari agenda riset ERP yang akan dilakukan untuk UKM di Indonesia. Small and Medium Enterprises (SMEs) in Indonesia has been able to contribute to the GDP (Gross Domestic Product) of 55.56% based on national data Planning Bureau of the Ministry of Cooperatives and SMEs of the Republic of Indonesia, in 2008. To expand market share and improve the competitiveness of SMEs, SMEs need an application that can integrate and automate business processes of SMEs. ERP applications can be one solution for SMEs because of the advantages that can be provided such as providing information with fast response time, increase the interaction between the departments of an organization, improving the management of ordering goods cycle, etc. Some of the critical issues faced by SMEs are the limited funds and information technology capabilities they have. In understanding the needs of the services required by SMEs for ERP applications and to provide guidance for SMEs and response to the lack of research about ERP in Indonesia, this research aims to describe the long-term plan maps of the ERP's research agenda that will be made for SMEs in Indonesia.

The impact of non-ideality on reconstructing spatial and temporal variations of aerosol acidity with multiphase buffer theory

2021 ◽  
Author(s):  
Yafang Cheng ◽  
Guangjie Zheng ◽  
Hang Su ◽  
Siwen Wang ◽  
Andrea Pozzer
Keyword(s):  
Molar Fraction ◽  
Temporal Variations ◽  
Spatial Variations ◽  
Acid Dissociation ◽  
Acid Dissociation Constant ◽  
Aerosol Acidity ◽  
Long Term Trends ◽  
Factor C ◽  
The Impact

&lt;p&gt;Aerosol acidity is a key parameter in atmospheric aqueous chemistry and strongly influence the interactions of air pollutants and ecosystem. The recently proposed multiphase buffer theory provides a framework to reconstruct long-term trends and spatial variations of aerosol pH based on the effective acid dissociation constant of ammonia (K&lt;sub&gt;a,NH3&lt;/sub&gt;&lt;sup&gt;*&lt;/sup&gt;). However, non-ideality in aerosol droplets is a major challenge limiting its broad applications. Here, we introduced a non-ideality correction factor (c&lt;sub&gt;ni&lt;/sub&gt;) and investigated its governing factors. We found that besides relative humidity (RH) and temperature, c&lt;sub&gt;ni&lt;/sub&gt; is mainly determined by the molar fraction of NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt; in aqueous-phase anions, due to different NH&lt;sub&gt;4&lt;/sub&gt;&lt;sup&gt;+&lt;/sup&gt; activity coefficients between (NH&lt;sub&gt;4&lt;/sub&gt;)&lt;sub&gt;2&lt;/sub&gt;SO&lt;sub&gt;4&lt;/sub&gt;- and NH&lt;sub&gt;4&lt;/sub&gt;NO&lt;sub&gt;3&lt;/sub&gt;-dominated aerosols. A parameterization method is thus proposed to estimate c&lt;sub&gt;ni&lt;/sub&gt; at given RH, temperature and NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt; fraction, and is validated against long-term observations and global simulations. In the ammonia-buffered regime, with c&lt;sub&gt;ni&lt;/sub&gt; correction the buffer theory can well reproduce the K&lt;sub&gt;a,NH3&lt;/sub&gt;&lt;sup&gt;*&lt;/sup&gt; predicted by comprehensive thermodynamic models, with root-mean-square deviation ~0.1 and correlation coefficient ~1. Note that, while c&lt;sub&gt;ni&lt;/sub&gt; is needed to predict K&lt;sub&gt;a,NH3&lt;/sub&gt;&lt;sup&gt;*&lt;/sup&gt; levels, it is usually not the dominant contributor to its variations, as ~90% of the temporal or spatial variations in K&lt;sub&gt;a,NH3&lt;/sub&gt;&lt;sup&gt;*&lt;/sup&gt; is due to variations in aerosol water and temperature.&lt;/p&gt;

Water in the Time of Drought II: Lessons from Droughts around the World

2021 ◽  
Author(s):  
Raphaëlle Ortiz ◽  
Anamaría Núñez ◽  
Corinne Cathala ◽  
Ana R. Rios ◽  
Mauro Nalesso
Keyword(s):  
Best Practices ◽  
Technical Note ◽  
Lessons Learned ◽  
Institutional Frameworks ◽  
The World ◽  
Relevant Case ◽  
Management Policies ◽  
Successes And Challenges

This technical note is an update to the previous "Water in the Time of Drought: Lessons from Five Droughts Around the World", published in 2018. It explores drought situations and policies in Spain (including the Canary Islands), Chile, Mexico, the dry corridor between Honduras, Guatemala, and El Salvador, Brazil, and South Africa. Each of these countries has recently dealt with droughts and/or developed long-term solutions to manage them. HydroBID, a tool developed by the IDB, will be presented through relevant case studies. After defining drought experiences and institutional frameworks in each country, the brief will explore the successes and challenges of national drought and water management policies. Best practices and lessons learned will be extracted from each case study to help policymakers better prepare for droughts.

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