A recording porometer with detachable cups operating on four separate leaves

1962 ◽  
Vol 156 (962) ◽  
pp. 1-13 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Carbon Dioxide Concentration ◽  
Ambient Air ◽  
Short Supply ◽  
Enhanced Sensitivity ◽  
Stomatal Behaviour ◽  
New Instrument ◽  
Leaf Surfaces ◽  
Increased Sensitivity ◽  
Experimental Treatments

A new form of recording resistance porometer is described which enables records of stomatal behaviour to be obtained concurrently from four different leaves; the porometer cups are automatically detached between readings, exposing the leaf surfaces to the ambient air in order to avoid artifacts due to changes in carbon dioxide concentration. The readings are recorded for the four leaves seriatim , the cup for each remaining attached for 3 min out of every ½ h. The results of several of the preliminary experiments carried out to test the new instrument are presented: 1. Continuous records for periods up to 6 days appear to have no serious effect on the functioning of the stomata under normal conditions. With Taraxacum officinale slightly greater stomatal opening was recorded on the fifth day than on the first; for wheat a slight falling off occurred on the third and fourth days, possibly due to ageing of the leaves. 2. The stomata of similar leaves on different plants which have been subjected throughout to the same sequence of conditions show remarkable uniformity of behaviour at any one time; a great increase in the precision of comparisons of experimental treatments should thus be achieved by applying them to such leaves and recording the results concurrently. 3. Experiments with plants of T . officinale , wheat and Xanthium pennsylvanicum subjected to increasing water strain have shown a marked closing response to the process of taking a reading (which involves forcing air through the leaf). This closing response is first seen some time before visible wilting occurs and for X. pennsylvanicum has been shown to be mainly if not entirely due to a greatly increased sensitivity to carbon dioxide. The biological implica­tions of this are discussed. The stomata (e. g. of T. officinale ) may not re-open fully for 2 or 3 days after re-watering, when the plant is recovering from water strain, but the enhanced sensitivity to readings is only shown while water is actually in short supply, and not during the period of recovery.

scholarly journals Design, Implementation and Data Analysis of an Embedded System for Measuring Environmental Quantities

Sensors ◽  
2020 ◽  
Vol 20 (8) ◽  
pp. 2304
Author(s):  
Martin Pieš ◽  
Radovan Hájovský ◽  
Jan Velička
Keyword(s):  
Carbon Dioxide ◽  
Data Analysis ◽  
Relative Humidity ◽  
Embedded System ◽  
Computer Science ◽  
Atmospheric Pressure ◽  
Electrical Engineering ◽  
Carbon Dioxide Concentration ◽  
Ambient Air ◽  
Analysis Data

The article describes the development and implementation of a complex monitoring system for measuring the concentration of carbon dioxide, ambient temperature, relative humidity and atmospheric pressure. The presented system was installed at two locations. The first was in the rooms at the Department of Cybernetics and Biomedical Engineering, Faculty of Electrical Engineering and Computer Science, VŠB-Technical University of Ostrava. The second was in the classrooms of the Grammar School and Secondary School of Electrical Engineering and Computer Science in Frenštát pod Radhoštěm. The article contains a detailed description of the entire measurement network, whose basic component was a device for measuring carbon dioxide concentration, temperature and relative humidity in ambient air and atmospheric pressure via wireless data transmission using IQRF® technology. Measurements were conducted continuously for several months. The data were archived in a database. The article also describes the methods for processing the data with statistical analysis. Carbon dioxide concentration was selected for data analysis. Data were selected from at least two different rooms at each location. The processed results represent the time periods for the given carbon dioxide concentrations. The graphs display in percent how much of the time students or employees spent exposed to safe or dangerous concentrations of carbon dioxide. The collected data were used for the future improvement of air quality in the rooms.

A Resource-Limited Approach to Estimating Algal Biomass Production With Geographical Fidelity

2010 ◽  
Author(s):  
David M. Wogan ◽  
Michael Webber ◽  
Alexandre K. da Silva
Keyword(s):  
Carbon Dioxide ◽  
Water Resources ◽  
Biomass Production ◽  
Flue Gas ◽  
Algal Biomass ◽  
Lipid Production ◽  
Carbon Dioxide Concentration ◽  
Ambient Air ◽  
The State ◽  
Resource Limited

This paper discusses the potential for algal biofuel production under resource-limited conditions in Texas. Algal biomass and lipid production quantities are estimated using a fully integrated biological and engineering model that incorporates primary resources required for growth, such as carbon dioxide, sunlight and water. The biomass and lipid production are estimated at the county resolution in Texas, which accounts for geographic variation in primary resources from the Eastern half of the state, which has moderate solar resources and abundant water resources, to the Western half of the state, which has abundant solar resources and moderate water resources. Two resource-limited scenarios are analyzed in this paper: the variation in algal biomass production as a function of carbon dioxide concentration and as a function of water availability. The initial carbon dioxide concentration, ranging from low concentrations in ambient air to higher concentrations found in power plant flue gas streams, affects the growth rate and production of algal biomass. The model compares biomass production using carbon dioxide available from flue gas or refinery activities, which are present only in a limited number of counties, with ambient concentrations found in the atmosphere. Biomass production is also estimated first for counties containing terrestrial sources of water such as wastewater and/or saline aquifers, and compared with those with additional water available from the Gulf of Mexico. The results of these analyses are presented on a series of maps depicting algal biomass and lipid production in gallons per year under each of the resource-limited scenarios. Based on the analysis, between 13.9 and 154.1 thousand tons of algal biomass and 1.0 and 11.1 million gallons of lipids can be produced annually.

Communication: Photoinduced Carbon Dioxide Binding with Surface-Functionalized Silicon Quantum Dots

2018 ◽  
Author(s):  
Oscar A. Douglas-Gallardo ◽  
Cristián Gabriel Sánchez ◽  
Esteban Vöhringer-Martinez
Keyword(s):  
Carbon Dioxide ◽  
Quantum Dots ◽  
Atmospheric Carbon Dioxide ◽  
Density Functional ◽  
Tight Binding ◽  
Carbon Dioxide Concentration ◽  
Research Area ◽  
Silicon Quantum Dots ◽  
Dependent Model ◽  
Photoinduced Charge

<div> <div> <div> <p>Nowadays, the search of efficient methods able to reduce the high atmospheric carbon dioxide concentration has turned into a very dynamic research area. Several environmental problems have been closely associated with the high atmospheric level of this greenhouse gas. Here, a novel system based on the use of surface-functionalized silicon quantum dots (sf -SiQDs) is theoretically proposed as a versatile device to bind carbon dioxide. Within this approach, carbon dioxide trapping is modulated by a photoinduced charge redistribution between the capping molecule and the silicon quantum dots (SiQDs). Chemical and electronic properties of the proposed SiQDs have been studied with Density Functional Theory (DFT) and Density Functional Tight-Binding (DFTB) approach along with a Time-Dependent model based on the DFTB (TD-DFTB) framework. To the best of our knowledge, this is the first report that proposes and explores the potential application of a versatile and friendly device based on the use of sf -SiQDs for photochemically activated carbon dioxide fixation. </p> </div> </div> </div>

Hyperspectral characteristics and leaf area index monitoring of rice (Oryza sativa L.) under carbon dioxide concentration enrichment

2021 ◽  
Vol 54 (3) ◽  
pp. 231-243
Author(s):  
Chao Liu ◽  
Zhenghua Hu ◽  
Rui Kong ◽  
Lingfei Yu ◽  
Yuanyuan Wang ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Oryza Sativa ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Oryza Sativa L ◽  
Carbon Dioxide Concentration ◽  
Area Index

scholarly journals Analysis of the possibility and molecular mechanism of carbon dioxide consumption in the Diels-Alder processes

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Karolina Kula ◽  
Agnieszka Kącka-Zych ◽  
Agnieszka Łapczuk-Krygier ◽  
Radomir Jasiński
Keyword(s):  
Carbon Dioxide ◽  
Molecular Mechanism ◽  
Lewis Acids ◽  
Chemical Reactivity ◽  
Carbon Dioxide Concentration ◽  
Diels Alder ◽  
Wide Range ◽  
Bet Analysis ◽  
Earth’S Climate ◽  
Step Mechanism

Abstract The large and significant increase in carbon dioxide concentration in the Earth’s atmosphere is a serious problem for humanity. The amount of CO2 is increasing steadily which causes a harmful greenhouse effect that damages the Earth’s climate. Therefore, one of the current trends in modern chemistry and chemical technology are issues related to its utilization. This work includes the analysis of the possibility of chemical consumption of CO2 in Diels-Alder processes under non-catalytic and catalytic conditions after prior activation of the C=O bond. In addition to the obvious benefits associated with CO2 utilization, such processes open up the possibility of universal synthesis of a wide range of internal carboxylates. These studies have been performed in the framework of Molecular Electron Density Theory as a modern view of the chemical reactivity. It has been found, that explored DA reactions catalyzed by Lewis acids with the boron core, proceeds via unique stepwise mechanism with the zwitterionic intermediate. Bonding Evolution Theory (BET) analysis of the molecular mechanism associated with the DA reaction between cyclopentadiene and carbon dioxide indicates that it takes place thorough a two-stage one-step mechanism, which is initialized by formation of C–C single bond. In turn, the DA reaction between cyclopentadiene and carbon dioxide catalysed by BH3 extends in the environment of DCM, indicates that it takes place through a two-step mechanism. First path of catalysed DA reaction is characterized by 10 different phases, while the second by eight topologically different phases.

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