scholarly journals Atmospheric CO2, CH4, and CO with CRDS technique at the Izaña Global GAW station: instrumental tests, developments and first measurement results

2017 ◽  
Author(s):  
Angel J. Gomez-Pelaez ◽  
Ramon Ramos ◽  
Emilio Cuevas ◽  
Vanessa Gomez-Trueba ◽  
Enrique Reyes
Keyword(s):  
Drift Rate ◽  
Inlet Pressure ◽  
Response Functions ◽  
Measurement Results ◽  
Ambient Measurements ◽  
Acceptance Tests ◽  
Term Maintenance

Abstract. At the end of 2015, a CO2/CH4/CO Cavity Ring-Down Spectrometer (CRDS) was installed at the Izaña Global Atmosphere Watch station (Tenerife, Spain) to improve the Izaña Greenhouse gases GAW measurement programme, and to guarantee the renewal of the instrumentation and the long-term maintenance of this programme. We present the results of the CRDS acceptance tests, the processing of raw data applied through novel numerical codes, and the response functions used. Also, the calibration results, the implemented water vapour correction, the target gas injection statistics, the ambient measurements performed from December 2015 to July 2017, and their comparison with other continuous in situ measurements are described. The agreement with other in situ continuous measurements is good most of the time for CO2 and CH4, but for CO is just outside the GAW 2-ppb objective. It seems the disagreement is not produced by significant drifts in the CRDS CO WMO tertiary standards. The main novelties are: 1) determination of a slight CO2 correction that takes into account changes in the inlet pressure/flow rate; 2) detailed justification of the use of virtual tanks to monitor the response function changes in time; 3) drift rate determination for the pressure and temperature sensors located inside the CRDS cavity; 4) novelties in the determination of the H2O correction for CO; and 5) determination and discussion of the origin of the CRDS-flow inlet pressure and H2O dependences.

scholarly journals Atmospheric CO<sub>2</sub>, CH<sub>4</sub>, and CO with the CRDS technique at the Izaña Global GAW station: instrumental tests, developments, and first measurement results

2019 ◽  
Vol 12 (4) ◽  
pp. 2043-2066 ◽  
Author(s):  
Angel J. Gomez-Pelaez ◽  
Ramon Ramos ◽  
Emilio Cuevas ◽  
Vanessa Gomez-Trueba ◽  
Enrique Reyes
Keyword(s):  
Flow Rate ◽  
Random Noise ◽  
Least Square ◽  
Spatial Inhomogeneity ◽  
Inlet Pressure ◽  
Processing Scheme ◽  
Linear Relationships ◽  
Least Square Fit

Abstract. At the end of 2015, a CO2/CH4/CO cavity ring-down spectrometer (CRDS) was installed at the Izaña Global Atmosphere Watch (GAW) station (Tenerife, Spain) to improve the Izaña Greenhouse Gases GAW Measurement Programme, and to guarantee the renewal of the instrumentation and the long-term maintenance of this program. We present the results of the CRDS acceptance tests, the raw data processing scheme applied, and the response functions used. Also, the calibration results, the implemented water vapor correction, the target gas injection statistics, the ambient measurements performed from December 2015 to July 2017, and their comparison with other continuous in situ measurements are described. The agreement with other in situ continuous measurements is good most of the time for CO2 and CH4, but for CO it is just outside the GAW 2 ppb objective. It seems the disagreement is not produced by significant drifts in the CRDS CO World Meteorological Organization (WMO) tertiary standards. The more relevant contributions of the present article are (1) determination of linear relationships between flow rate, CRDS inlet pressure, and CRDS outlet valve aperture; (2) determination of a slight CO2 correction that takes into account changes in the inlet pressure/flow rate (as well as its stability over the years), and attributing it to the existence of a small spatial inhomogeneity in the pressure field inside the CRDS cavity due to the gas dynamics; (3) drift rate determination for the pressure and temperature sensors located inside the CRDS cavity from the CO2 and CH4 response function drift trends; (4) the determination of the H2O correction for CO has been performed using raw spectral peak data instead of the raw CO provided by the CRDS and using a running mean to smooth random noise in a long water-droplet test (12 h) before performing the least square fit; and (5) the existence of a small H2O dependence in the CRDS flow and of a small spatial inhomogeneity in the temperature field inside the CRDS cavity are pointed out and their origin discussed.

scholarly journals On-farm orchards of fruit trees

2010 ◽  
Vol 46 (Special Issue) ◽  
pp. S65-S69
Author(s):  
F. Paprštein ◽  
J. Sedlák ◽  
V. Holubec
Keyword(s):  
National Park ◽  
Fruit Trees ◽  
On Farm Conservation ◽  
Nursery Stock ◽  
Planting Materials ◽  
On Farm ◽  
The Given

Four on-farm plantations (KRNAP Vrchlabí, the Orchard of Reconciliation in Neratov, Podyjí National Park, and Šumava National Park) were successfully established in a traditional form, with large orchard trees on seedling rootstocks. Certain accessions (cultivars) for on-farm conservation in the given locality were selected, according to the incidence and presentation of genotypes in these particular areas. This information was obtained by localization of fruit trees <I>in situ </I>and the determination of certain cultivars. Nursery stock production for onfarm plantations is described. Because of the longevity of the plantation, seedling rootstocks were used for the production of planting materials for the on-farm plantations. Techniques of on-farm plantation establishment and orchard management are stated within the paper. Four established on-farm plantations have ensured the long-term preservation of landraces in their original areas.

scholarly journals Long-term maintenance of human nai ve T cells through in situ homeostasis in lymphoid tissue sites

2016 ◽  
Vol 1 (6) ◽  
pp. eaah6506-eaah6506 ◽  
Author(s):  
J. J. C. Thome ◽  
B. Grinshpun ◽  
B. V. Kumar ◽  
M. Kubota ◽  
Y. Ohmura ◽  
...  
Keyword(s):  
T Cells ◽  
Lymphoid Tissue ◽  
Term Maintenance

Heterogeneity Influence of Organic Matter on the Ozonation Chemiluminescence for Soils and Sediments

2012 ◽  
Vol 468-471 ◽  
pp. 1850-1855 ◽  
Author(s):  
Meng De Liu ◽  
Ping Ping Fan ◽  
Liu Yan ◽  
Li Bin Du ◽  
Guang Li Hou ◽  
...  
Keyword(s):  
Organic Matter ◽  
Rapid Determination ◽  
Marine Ecosystems ◽  
Soils And Sediments ◽  
Luminescence Time ◽  
Luminescence Characteristics ◽  
Soluble Fractions

Organic matter in soils and sediments is the key object of biogeochemistry in both terrestrial and marine ecosystems. Whether organic matter is the source or sink of carbon and nutrients can be predicted by its compositions and need continuous, long-term observations of organic matter compositions; therefore, in situ technologies are being investigated to meet the continuous, long-term observations. This study tried to explore a rapid determination of organic matter compositions by ozone chemiluminescence. After the soils or sediments were oxidized by ozone, their chemiluminescence characteristics such as luminescence maximum and time differed significantly. We hypothesized that the luminescence characteristics is controlled by the organic matter compositions. The soils and sediments were separated into extractives, acid soluble fractions (AS), and acid insoluble fractions (AIF), and then the original samples and their compositions were oxidized by ozone. Different organic matter compositions play a different role in the luminescence characteristics: extractives inhibited the luminescence maximum and luminescence time, AS increased the luminescence time and AIF increased the luminescence maximum. Results also showed that AIF can explain most variation of luminescence characteristics, suggesting that the luminescence characteristics are mainly controlled by the concentrations of AIF. Our study suggested that ozonaiton chemiluminescence have a strong potential to rapidly determine the chemistry of soils and sediments.

scholarly journals Efficient Oxidase Biosensors Based on Bioelectrocatalytic Surfaces of Electrodeposited Ferrocenyl Polycyclosiloxanes—Pt Nanoparticles

Chemosensors ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 81
Author(s):  
Alvaro Boluda ◽  
Carmen Casado ◽  
Beatriz Alonso ◽  
M. García Armada
Keyword(s):  
Xanthine Oxidase ◽  
Metallic Nanoparticles ◽  
Pt Nanoparticles ◽  
Covalent Immobilization ◽  
New Device ◽  
Long Term Stability ◽  
Fish Meat

The in-situ synthesis of catalytic surfaces with metallic nanoparticles must overcome the issues related to particle aggregation and polydispersity in the particle size. This work achieves it by using two electrodeposited ferrocenyl polycyclosiloxane polymers (MFPP and FPP) as templates for electro-synthesize Pt nanoparticles (PtNPS). In addition, this new electrode surface combines two efficient electrocatalysts: Ferrocene and Pt nanoparticles, with synergistic biocatalytic properties that constitute an electrocatalytic framework for the covalent immobilization of xanthine oxidase. In this work, we present the results of the kinetic, electrochemical and analytical studies of the prepared electrodes. These results showed that the PtNPs/FPP system is the best bioelectrocatalytic surface and improves other more complex xanthine oxidase devices based on the hydrogen peroxide oxidation, allowing the use of lower measuring potential with good sensitivity, wider linear ranges and low detection limits. In addition, this electrode provides the novelty of allowing the measurement of xanthine through the enzymatic consumption of oxygen at potential −0.1 V with a sensitivity of 1.10 A M−1 cm−2, linear ranges of 0.01–0.1 and 0.1–1.4 mM, low detection limit (48 nM) and long-term stability. The new device has been successfully applied to the determination of xanthine in fish meat.

scholarly journals In-situ Measurements in Overconsolidated Clay

2015 ◽  
Vol 3 (1-2) ◽  
pp. 68-76
Author(s):  
Eszter Horvath-Kalman
Keyword(s):  
Earth Pressure ◽  
Young Modulus ◽  
In Situ Measurements ◽  
The Other ◽  
Physical Parameters ◽  
Measurement Results ◽  
Processing Of Measurement Results ◽  
Overconsolidated Soils

Abstract The study is about the general genesis process of overconsolidated soils, as well as the effects of the overconsolidated ratio to structures. It will demonstrate the possible methods for the determination of the values of overconsolidated ratio and of earth pressure at rest and of the other soil-physical parameters; further, the processing of measurement results, through which the values of OCR (Overconsolidated ratio) and of λ0 (Earth pressure at rest) and of c, E soil-physical parameters (friction angles, cohesion and Young modulus) in the Kiscelli Clay Marl have been determined by Selfboring Pressuremeter.

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