Method for Monitoring Nitrogen Gas Exchange from Plant Foliage

Crop Science ◽  
1985 ◽  
Vol 25 (2) ◽  
pp. 359 ◽  
Author(s):  
R. T. Weiland ◽  
T. E. Omholt
2021 ◽  
Vol 13 (2) ◽  
pp. 791-797
Author(s):  
Mansha Gul ◽  
F. A. Khan ◽  
Shafiq A Wani ◽  
S. A. Bhat ◽  
S. A. Mir ◽  
...  

Considering the rich nutritional status and possibility of broccoli in improving the profitable yield, and wide role of Mel in regulating the plant physiological process, an investigation was carried out at the division of Basic Sciences and Humanities during 2017 to investigate the effect of foliar application of Mel on leaf photosynthetic and biochemical attributes broccoli. Thirty days old and uniform seedlings of broccoli cv. Palam Samridhi were transplanted in the field at a spacing of 45 × 45cm. Different concentrations of Mel, viz. 0, 20, 40, 60 and 80 ppm were sprayed on the plant foliage at 15 days after transplanting (DAT) replicating each treatment four times. Leaf gas exchange and biochemical attributes were tested following the standard procedures. The Results showed the lowest stipulated rate of photosynthesis (10.87 µmole.m-2.sec-1), stomatal conductance (301.44 mole H2O.m-2ses-1) and leaf transpiration (1. 14 mole H2O.m-2ses-1) in untreated plants.  Different doses of Mel significantly increased the values of these attributes and the highest values of photosynthesis (18.63 µmole.m-2.sec-1), stomatal conductance (324.37 mmole.m-2.ses-1) and leaf transpiration (3.23 mmole.m-2.ses-1) with Mel 60 ppm were recorded. The alterations in different biochemical attributes were also evident due to foliar application of Mel and maximum leaf sugar (77.0 and 85.9µg/g), protein (56.9 and 77.3 µg/g), total phenols (260.1 and 339.9 mg/100g), antioxidants (142.8 and 159.9 mg GAE /100g DW) and MSI (94.89 and 97.43 percent) values with Mel 60ppm at 30 and 60DAT, respectively. Therefore, the present study signifies the useful effects of Mel in regulating the physio-biochemical properties of broccoli.


1986 ◽  
Vol 95 (4) ◽  
pp. 369-372 ◽  
Author(s):  
Archie L. Yee ◽  
Erdem I. Cantekin

The effect of alterations in the systemic oxygen tension on middle ear (ME) gas exchange was studied in three juvenile rhesus monkeys ( Macaca mulatta) using five different inspired oxygen concentrations ranging from 15% to 100%. The anesthetized animals were ventilated for 4 hours, breathing the set of predetermined, constant oxygen-nitrogen gas mixtures. During this period, arterial and venous oxygen and carbon dioxide partial pressures were measured at 30-minute intervals; total ME gas pressure was determined indirectly using tympanometry at 10-minute intervals. Systemic oxygen blood gas tension showed predictable changes which were dependent on the fraction of inspired oxygen. However, fluctuations in the total ME gas pressure were insignificant. Findings suggested that increased systemic oxygen partial pressure does not influence ME gas exchange.


1992 ◽  
Vol 5 (2) ◽  
pp. 109-113 ◽  
Author(s):  
Matsuo Yasuda ◽  
Hajime Nishino ◽  
Mikio Tanaka ◽  
Tokiko Chiba ◽  
Hisako Nakano ◽  
...  

2008 ◽  
Vol 72 (2) ◽  
pp. 393-401 ◽  
Author(s):  
Jaydene T. Welzmiller ◽  
Allan D. Matthias ◽  
Scott White ◽  
Thomas L. Thompson

Author(s):  
C. E. Cluthe ◽  
G. G. Cocks

Aqueous solutions of a 1 weight-per cent poly (ethylene oxide) (PEO) were degassed under vacuum, transferred to a parallel plate viscometer under a nitrogen gas blanket, and exposed to Co60 gamma radiation. The Co60 source was rated at 4000 curies, and the dose ratewas 3.8x105 rads/hr. The poly (ethylene oxide) employed in the irradiations had an initial viscosity average molecular weight of 2.1 x 106.The solutions were gelled by a free radical reaction with dosages ranging from 5x104 rads to 4.8x106 rads.


Author(s):  
John G. Sheehan

The goal is to examine with high resolution cryo-SEM aqueous particulate suspensions used in coatings for printable paper. A metal-coating chamber for cryo-preparation of such suspensions was described previously. Here, a new conduction-cooling system for the stage and cold-trap in an SEM specimen chamber is described. Its advantages and disadvantages are compared to a convection-cooling system made by Hexland (model CT1000A) and its mechanical stability is demonstrated by examining a sample of styrene-butadiene latex.In recent high resolution cryo-SEM, some stages are cooled by conduction, others by convection. In the latter, heat is convected from the specimen stage by cold nitrogen gas from a liquid-nitrogen cooled evaporative heat exchanger. The advantage is the fast cooling: the Hexland CT1000A cools the stage from ambient temperature to 88 K in about 20 min. However it consumes huge amounts of liquid-nitrogen and nitrogen gas: about 1 ℓ/h of liquid-nitrogen and 400 gm/h of nitrogen gas. Its liquid-nitrogen vessel must be re-filled at least every 40 min.


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