Transpirational Surges in Tamarix and Eucalyptus as Measured with an Infrared Gas Analyzer

A method for collecting an isotopically representative sample of CO2 from an air stream using a zeolite molecular sieve is described. A robust sampling system was designed and developed for use in the field that includes reusable molecular sieve cartridges, a lightweight pump, and a portable infrared gas analyzer (IRGA). The system was tested using international isotopic standards (13C and 14C). Results showed that CO2 could be trapped and recovered for both δ13C and 14C analysis by isotope ratio mass spectrometry (IRMS) and accelerator mass spectrometry (AMS), respectively, without any contamination, fractionation, or memory effect. The system was primarily designed for use in carbon isotope studies of ecosystem respiration, with potential for use in other applications that require CO2 collection from air.

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Application to Woody Plants of a Rapid Method for Determining Leaf CO2 Compensation Concentrations

Canadian Journal of Forest Research ◽

10.1139/x73-032 ◽

1973 ◽

Vol 3 (2) ◽

pp. 237-242 ◽

Cited By ~ 7

Author(s):

D. I. Dickmann ◽

D. H. Gjerstad

Keyword(s):

Rapid Method ◽

Woody Plants ◽

Woody Species ◽

Moisture Stress ◽

Gas Analysis ◽

Deionized Water ◽

Controlled Environment ◽

Gas Analyzer ◽

Leaf Ontogeny ◽

Infrared Gas Analyzer

A rapid method of determining CO2 compensation concentrations was developed and applied to woody plants. Whole leaves, needle fascicles, and twigs were excised, the cut ends inserted in a vial of deionized water, and the assembly placed in a Mylar bag. The bag was filled with air containing ca. 400 p.p.m. CO2. After 1 h in a growth chamber (24 °C, 3800 ft-c (40 660 lux)), the air was expelled from the bag through an infrared gas analyzer. Compensation concentrations determined by this method agreed with values obtained by using conventional closed-circuit gas analysis. The method was successfully applied to 14 gymnosperm and 55 angiosperm woody species and clones, including field-grown plants and rooted cuttings grown under controlled environment. Variation among species was small, compensation concentrations usually falling between 55 and 65 p.p.m. CO2, the range associated with C3 plants. The influence of temperature, moisture stress, and leaf ontogeny on leaf CO2 compensation also was studied.

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Nondispersive Infrared Gas Analyzer for Vapor Density Measurements of a Carbonyl-Containing Organometallic Cobalt Precursor

Applied Spectroscopy ◽

10.1177/0003702817716939 ◽

2017 ◽

Vol 71 (12) ◽

pp. 2632-2642 ◽

Cited By ~ 4

Author(s):

James E. Maslar ◽

William A. Kimes ◽

Brent A. Sperling ◽

Ravindra K. Kanjolia

Keyword(s):

Bandpass Filter ◽

Sampling Rate ◽

Signal Averaging ◽

Gas Analyzer ◽

Vapor Density ◽

Flow Conditions ◽

Ft Ir ◽

Infrared Gas Analyzer ◽

Ft Ir Spectroscopy

A nondispersive infrared (NDIR) gas analyzer was demonstrated for measuring the vapor-phase density of the carbonyl-containing organometallic cobalt precurso μ2-η2-(tBu-acetylene) dicobalthexacarbonyl (CCTBA). This sensor was based on direct absorption by CCTBA vapor in the C≡O stretching spectral region and utilized a stable, broadband IR filament source, an optical chopper to modulate the source, a bandpass filter for wavelength isolation, and an InSb detector. The optical system was calibrated by selecting a calibration factor to convert CCTBA absorbance to a partial pressure that, when used to calculate CCTBA flow rate and CCTBA mass removed from the ampoule, resulted in an optically determined mass that was nominally equal to a gravimetrically-determined mass. In situ Fourier transform infrared (FT-IR) spectroscopy was performed simultaneously with the NDIR gas analyzer measurements under selected conditions in order to characterize potential spectroscopic interferences. Interference due to CO evolution from CCTBA was found to be small under the flow conditions employed here. A CCTBA minimum detectable molecular density as low as ≈3 × 1013 cm−3 was calculated (with no signal averaging and for a sampling rate of 200 Hz). While this NDIR gas analyzer was specifically tested for CCTBA, it is suitable for characterizing the vapor delivery of a range of carbonyl-containing precursors.

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TROCAS GASOSAS EM PLANTAS DE CANA-DE-AÇÚCAR INOCULADAS COM GLUCONACETOBACTER DIAZOTROPHICUS E SUBMETIDAS AOS ESTRESSES SALINO E HÍDRICO

Multi-Science Research ◽

10.47621/m-sr.2020.v.3.n.1.63-034 ◽

2020 ◽

Vol 03 (01) ◽

pp. 57-63

Author(s):

Janice Dias ◽

Keyword(s):

Abiotic Stress ◽

Stomatal Conductance ◽

Gas Exchange ◽

Endophytic Bacteria ◽

Gluconacetobacter Diazotrophicus ◽

Gas Analyzer ◽

Sugarcane Crop ◽

Lower Productivity ◽

High Doses ◽

Infrared Gas Analyzer

The sugarcane crop isconsidered moderately sensitive to environmental stresses, which results in reduced growth and lower productivity. In addition, there is a need for the application of high doses of nitrogen fertilizer. A potential and agroecologically correct alternative is the use of nitrogen-fixing endophytic bacteria, such as Gluconacetobacter diazotrophicus. However, under conditions of abiotic stress the benefits from this plant-endophyte association can be altered due to the physiology of stress response. The objective of this work was to study the effect of inoculation of G. diazotrophicus by means of the evaluation of the parameters of gas exchange, in sugarcane plants submitted to salt and water stresses. The rates of stomatal conductance, transpiration and liquid photosynthesis were evaluated by means of a portable infrared gas analyzer (IRGA). The results showed that the presence of the bacteria may alter the rates of stomatal conductance and transpiration, interfering in the physiology of response to salinity and drought. Keywords: Endophytic bactéria. Stomatal conductance. Transpiration. Salinity. Drought.

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Infrared Gas Analyzer for Low Concentrations of Carbon Dioxide

Analytical Chemistry ◽

10.1021/ac60063a052 ◽

1952 ◽

Vol 24 (3) ◽

pp. 591-591 ◽

Cited By ~ 6

Author(s):

J. M. Watkins ◽

C. L. Gemmill

Keyword(s):

Carbon Dioxide ◽

Gas Analyzer ◽

Low Concentrations ◽

Infrared Gas Analyzer

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Barnyardgrass control using tank-mixed herbicides with saflufenacil and its influence in photosynthesis and chlorophyll fluorescence

Ciência Rural ◽

10.1590/0103-8478cr20190919 ◽

2020 ◽

Vol 50 (7) ◽

Author(s):

Cassiano Salin Pigatto ◽

Camila Peligrinotti Tarouco ◽

Fernando Teixeira Nicoloso ◽

Álvaro Luis Pasquetti Berghetti ◽

Glauco Pacheco Leães ◽

...

Keyword(s):

Chlorophyll Fluorescence ◽

Dry Matter ◽

Photosynthetic Parameters ◽

Gas Analyzer ◽

Herbicide Application ◽

Chlorophyll Fluorescence Parameters ◽

Fluorescence Parameters ◽

Negative Effect ◽

And Control ◽

Infrared Gas Analyzer

ABSTRACT: The objectives of this research were to evaluate the interaction between herbicides mixed with saflufenacil for the control of barnyardgrass and to determine the effect on photosynthetic and chlorophyll fluorescence parameters. The experiment was conducted in a greenhouse in a 2x8 factorial scheme, whose factor A tested resistant and susceptible biotypes; and factor B the herbicides: saflufenacil (70 g a.i. ha-1), clomazone (180 g a.i. ha-1), imazapyr + imazapic (73.5 + 24.5 g a.i. ha-1), and cyhalofop (360 g a.i. ha-1), the mixtures of these herbicides with saflufenacil, and control without treatment. Weed control was assessed 7, 14, 21 and 28 days after herbicide application (DAA), as well as shoot dry matter at 28 DAA, photosynthetic parameters using infrared gas analyzer (IRGA), and emission of chlorophyll a fluorescence after 24 and 28 hours of application of treatments, respectively, and interaction of herbicides. Combination of saflufenacil with the herbicides tested in general did not change the response of both barnyardgrass biotypes to the herbicides used. The resistant biotype showed a lower negative effect on chlorophyll fluorescence and photosynthesis parameters in the combination of herbicides with saflufenacil. The herbicide cyhalofop was effective for the control of ALS-susceptible and resistant barnyardgrass.

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An Automated Chamber System for Measurements of Whole-vine Gas Exchange

HortScience ◽

10.21273/hortsci.32.1.64 ◽

1997 ◽

Vol 32 (1) ◽

pp. 64-67 ◽

Cited By ~ 26

Author(s):

S. Poni ◽

E. Magnanini ◽

B. Rebucci

Keyword(s):

Gas Exchange ◽

Low Cost ◽

Absolute Humidity ◽

Gas Analyzer ◽

Custom Made ◽

Automated Measurements ◽

System Interfaces ◽

And Control ◽

Measurement And Control ◽

Infrared Gas Analyzer

The reported system interfaces a commercially available portable infrared gas analyzer with a measurement and control module for continuous and automated measurements of whole-canopy gas exchange. Readings were taken for several days, under mostly sunny or partly cloudy conditions, on two potted vines (total leaf area per vine of ≈1.3 m2) enclosed in inflated polyethylene chambers. The air flow rate through the chambers was provided by a centrifugal blower and set at 5 L·s-1 by a butterfly valve. It prevented ΔCO2 from dropping below –40 mL·L-1. Switching of the two CO2 analysis channels to the infrared gas analyzer (operated in a differential mode) was achieved by solenoid valves, whereas wet and dry-bulb temperatures at chambers' inlet and outlet were measured by low-cost, custom-made thermocouple psychrometers. Whole-vine assimilation rate (WVA) and whole-vine transpiration rate were calculated from the inlet—outlet differences in CO2 and absolute humidity. When compared to assimilation measured on single leaves (SLA) under saturating light at equivalent times, the WVA reduction (area basis) was ≈50%, suggesting that whole-canopy photosynthetic efficiency based on SLA readings can be greatly overestimated.

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