The Effect of Temperature Preconditioning on the Temperature Sensitivity of Net CO2 Flux in Geographically Diverse Populations of the Moss Polytrichum Commune

Ecology ◽  
1983 ◽  
Vol 64 (5) ◽  
pp. 1100-1108 ◽  
Author(s):  
Bjartmar Sveinbjornsson ◽  
Walter C. Oechel
Keyword(s):  
Temperature Sensitivity ◽  
Co2 Flux ◽  
Effect Of Temperature ◽  
Diverse Populations ◽  
Polytrichum Commune

Temperature Sensitivity Analysis of Extended Source Double Gate Tunnel Field Effect Transistor

2021 ◽  
Author(s):  
Dharmender Nishad ◽  
Kaushal Nigam ◽  
Satyendra Kumar
Keyword(s):  
Temperature Sensitivity ◽  
Computer Aided Design ◽  
Field Effect ◽  
Field Effect Transistor ◽  
Effect Of Temperature ◽  
Double Gate ◽  
Extended Source ◽  
Temperature Variations ◽  
Effect Transistor ◽  
Tunnel Field Effect Transistor

Abstract Temperature-induced performance variation is one of the main concerns of the conventional stack gate oxide double gate tunnel field-effect transistor (SGO-DG-TFET). In this regard, we investigate the temperature sensitivity of extended source double gate tunnel field-effect transistor (ESDG-TFET). For this, we have analyzed the effect of temperature variations on the transfer characteristics, analog/RF, linearity and distortion figure of merits (FOMs) using technology computer aided design (TCAD) simulations. Further, the temperature sensitivity performance is compared with conventional SGO-DG-TFET. The comparative analysis shows that ESDG-TFET is less sensitive to temperature variations compared to the conventional SGO-DG-TFET. Therefore, this indicates that ESDG-TFET is more reliable for low-power, high-frequency applications at a higher temperature compared to conventional SGO-DG-TFET.

scholarly journals Temperature-mediated changes in microbial carbon use efficiency and <sup>13</sup>C discrimination

2016 ◽  
Vol 13 (11) ◽  
pp. 3319-3329 ◽  
Author(s):  
Christoph A. Lehmeier ◽  
Ford Ballantyne IV ◽  
Kyungjin Min ◽  
Sharon A. Billings
Keyword(s):  
Respiration Rate ◽  
Multiple Scales ◽  
Microbial Transformation ◽  
Co2 Flux ◽  
Effect Of Temperature ◽  
Organic Substrates ◽  
Ecosystem Level ◽  
Microbial Carbon ◽  
Use Efficiency ◽  
Carbon Dioxide Co2

Abstract. Understanding how carbon dioxide (CO2) flux from ecosystems feeds back to climate warming depends in part on our ability to quantify the efficiency with which microorganisms convert organic carbon (C) into either biomass or CO2. Quantifying ecosystem-level respiratory CO2 losses often also requires assumptions about stable C isotope fractionations associated with the microbial transformation of organic substrates. However, the diversity of organic substrates' δ13C and the challenges of measuring microbial C use efficiency (CUE) in their natural environment fundamentally limit our ability to project ecosystem C budgets in a warming climate. Here, we quantify the effect of temperature on C fluxes during metabolic transformations of cellobiose, a common microbial substrate, by a cosmopolitan microorganism growing at a constant rate. Biomass C specific respiration rate increased by 250 % between 13 and 26.5 °C, decreasing CUE from 77 to 56 %. Biomass C specific respiration rate was positively correlated with an increase in respiratory 13C discrimination from 4.4 to 6.7 ‰ across the same temperature range. This first demonstration of a direct link between temperature, microbial CUE, and associated isotope fluxes provides a critical step towards understanding δ13C of respired CO2 at multiple scales, and towards a framework for predicting future ecosystem C fluxes.

Design of temperature-immunization system packaging for the resonant pressure sensor

2017 ◽  
Vol 31 (08) ◽  
pp. 1750085 ◽  
Author(s):  
Anlin Li ◽  
Chenying Zhang ◽  
Huan Wang ◽  
Yong He ◽  
Daoheng Sun ◽  
...  
Keyword(s):  
Resonant Frequency ◽  
Temperature Sensitivity ◽  
Pressure Sensor ◽  
Coefficient Of Thermal Expansion ◽  
Effect Of Temperature ◽  
Element Simulation ◽  
Different Temperatures ◽  
Time Changes ◽  
Packaging Structure ◽  
System Packaging

Based on the study of the material matching and structure cooperating, this paper mainly explores a new packaging structure with low thermal mismatches which can enhance the accuracy and stability of the resonant pressure sensor. According to the finite element simulation, the rule of the coefficient of thermal expansion (CTE) and the depth of the groove on the substrate, which has an influence on the temperature sensitivity, could be obtained. By analyzing the effect of temperature on the resonant frequency, it shows the temperature sensitivity of the new packaging structure is −0.97 Hz/[Formula: see text]C in 20 kPa, under the temperature range of 30[Formula: see text]C to 80[Formula: see text]C. After analyzing resonant frequency stability at different temperatures, it is found that the time for achieving stability at different temperatures of the new packaging structure is at least 10 min less than that of TO packaging structure. The average frequency’s relative variation ratio of the new packaging structure at different temperatures remains roughly the same, and the variation range is within ±[Formula: see text]0.005% as time changes. These results indicate that the new packaging structure has the characteristic of great temperature-immunization.

scholarly journals Environmental correlates of peatland carbon fluxes in a thawing landscape: do transitional thaw stages matter?

2015 ◽  
Vol 12 (1) ◽  
pp. 445-480 ◽  
Author(s):  
A. Malhotra ◽  
N. T. Roulet
Keyword(s):  
Temperature Sensitivity ◽  
Structural Changes ◽  
Co2 Flux ◽  
Apparent Temperature ◽  
Ecosystem Structure ◽  
Environmental Correlates ◽  
C Storage ◽  
Discontinuous Permafrost ◽  
Significant Area ◽  
And Function

Abstract. Peatlands in discontinuous permafrost regions occur as a mosaic of wetland types, each with variable sensitivity to climate change. Permafrost thaw further increases the spatial heterogeneity in ecosystem structure and function in peatlands. Carbon (C) fluxes are well characterized in end-member thaw stages such as fully intact or fully thawed permafrost but remain unconstrained for transitional stages that cover a significant area of thawing peatlands. Furthermore, changes in the environmental correlates of C fluxes, due to thaw are not well described: a requirement for modeling future changes to C storage of permafrost peatlands. We investigated C fluxes and their correlates in end-member and a number of transitional thaw stages in a sub-arctic peatland. Across peatland lumped CH4 and CO2 flux data had significant correlations with expected correlates such as water table depth, thaw depth, temperature, photosynthetically active radiation and vascular green area. Within individual thaw states, bivariate correlations as well as multiple regressions between C flux and environmental factors changed variably with increasing thaw. The variability in directions and magnitudes of correlates reflects the range of structural conditions that could be present along a thaw gradient. These structural changes correspond to changes in C flux controls, such as temperature and moisture, and their interactions. Temperature sensitivity of CH4 increased with increasing thaw in bivariate analyses, but lack of this trend in multiple regression analyses suggested cofounding effects of substrate or water limitation on the apparent temperature sensitivity. Our results emphasize the importance of incorporating transitional stages of thaw in landscape level C budgets and highlight that end-member or adjacent thaw stages do not adequately describe the variability in structure-function relationships present along a thaw gradient.

The effect of temperature on the outward currents in the soma of molluscan neurones in voltage-clamp conditions

1975 ◽  
Vol 62 (2) ◽  
pp. 265-275
Author(s):  
I. S. Masgura ◽  
A. E. Valeyev ◽  
I. Z. Zamekhovsky
Keyword(s):  
Surface Potential ◽  
Temperature Sensitivity ◽  
Potassium Conductance ◽  
Outward Current ◽  
Effect Of Temperature ◽  
Transient Outward Current ◽  
Transient Component ◽  
Outward Currents ◽  
Snail Neurones ◽  
Negative Surface

The delayed outward current in snail neurones was separated into two components with different temperature sensitivity: (i) a persistent component and (ii) a transient (inactivating) component. The effect of cooling on the value of the transient current is strongly dependent upon the value of the conditioning potential. It was supposed that cooling causes a decrease in the negative surface potential in the vicinity of the potassium pathways and removes their inactivation. Simultaneously cooling depresses the potassium conductance. The effect on surface potential is more distinct with conditioning potentials at which a significant fraction of the transient outward current is inactivated. The effect of cooling on the transient component of the fast outward current was similar to that on the transient component of the delayed outward current.

scholarly journals Environmental correlates of peatland carbon fluxes in a thawing landscape: do transitional thaw stages matter?

2015 ◽  
Vol 12 (10) ◽  
pp. 3119-3130 ◽  
Author(s):  
A. Malhotra ◽  
N. T. Roulet
Keyword(s):  
Temperature Sensitivity ◽  
Structural Changes ◽  
Co2 Flux ◽  
Apparent Temperature ◽  
Ecosystem Structure ◽  
Environmental Correlates ◽  
C Storage ◽  
Discontinuous Permafrost ◽  
Significant Area ◽  
And Function

Abstract. Peatlands in discontinuous permafrost regions occur as a mosaic of wetland types, each with variable sensitivity to climate change. Permafrost thaw further increases the spatial heterogeneity in ecosystem structure and function in peatlands. Carbon (C) fluxes are well characterized in end-member thaw stages such as fully intact or fully thawed permafrost but remain unconstrained for transitional stages that cover a significant area of thawing peatlands. Furthermore, changes in the environmental correlates of C fluxes, due to thaw, are not well described – a requirement for modeling future changes to C storage of permafrost peatlands. We investigated C fluxes and their correlates in end-member and a number of transitional thaw stages in a sub-arctic peatland. Across peatland-lumped CH4 and CO2 flux data had significant correlations with expected correlates such as water table depth, thaw depth, temperature, photosynthetically active radiation and vascular green area. Within individual thaw states, bivariate correlations as well as multiple regressions between C flux and environmental factors changed variably with increasing thaw. The variability in directions and magnitudes of correlates reflects the range of structural conditions that could be present along a thaw gradient. These structural changes correspond to changes in C flux controls, such as temperature and moisture, and their interactions. Temperature sensitivity of CH4 increased with increasing thaw in bivariate analyses, but lack of this trend in multiple regression analyses suggested cofounding effects of substrate or water limitation on the apparent temperature sensitivity. Our results emphasize the importance of incorporating transitional stages of thaw in landscape level C budgets and highlight that end-member or adjacent thaw stages do not adequately describe the variability in structure-function relationships present along a thaw gradient.

scholarly journals Soil moisture influenced the interannual variation in temperature sensitivity of soil organic carbon mineralization in the Loess Plateau

2015 ◽  
Vol 12 (2) ◽  
pp. 1453-1474 ◽  
Author(s):  
Y. Zhang ◽  
S. Guo ◽  
M. Zhao ◽  
L. Du ◽  
R. Li ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Carbon Cycle ◽  
Loess Plateau ◽  
Temperature Sensitivity ◽  
Interannual Variation ◽  
Carbon Mineralization ◽  
Co2 Flux ◽  
The Loess Plateau ◽  
Local Soil ◽  
Soc Mineralization

Abstract. Temperature sensitivity of SOC mineralization (Q10) determines how strong the feedback from global warming may be on the atmospheric CO2 concentration, thus understanding the factors influencing the interannual variation in Q10 is important to accurately estimate the local soil carbon cycle. In situ SOC mineralization was measured using an automated CO2 flux system (Li-8100) in long-term bare fallow soil in the Loess Plateau (35° 12' N, 107° 40' E) in Changwu, Shaanxi, China form 2008 to 2013. The results showed that the annual cumulative SOC mineralization ranged from 226 to 298 g C m−2 y−1 (mean =253 g C m−2 y−1; CV =13%), annual Q10 ranged from 1.48 to 1.94 (mean =1.70; CV =10%), and annual soil moisture content ranged from 38.6 to 50.7% WFPS (mean =43.8% WFPS; CV =11%), which were mainly affected by the frequency and distribution of precipitation. Annual Q10 showed a negative quadratic correlation with soil moisture. In conclusion, understanding of the relationships between interannual variation in Q10 of SOC mineralization, soil moisture and precipitation is important to accurately estimate the local carbon cycle, especially under the changing climate.

scholarly journals Temperature Sensitivity of CO2 and CH4 Fluxes from Coarse Woody Debris in Northern Boreal Forests

Forests ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 624
Author(s):  
Liudmila Mukhortova ◽  
Natalia Pashenova ◽  
Maria Meteleva ◽  
Leonid Krivobokov ◽  
Georg Guggenberger
Keyword(s):  
Temperature Sensitivity ◽  
Coarse Woody Debris ◽  
Boreal Forests ◽  
Woody Debris ◽  
Co2 Flux ◽  
Methane Flux ◽  
Main Process ◽  
Strong Positive Correlation ◽  
Biological Source ◽  
Higher Temperature

Carbon dioxide (CO2) and methane (CH4) are recognized as the main greenhouse gases causing climate warming. In forest ecosystems, the death of trees leads to the formation of coarse woody debris (CWD) that is one of the sources of greenhouse gas emissions due to wood decomposition. We quantified the CO2 and CH4 fluxes from CWD of larch (Larix gmelinii (Rupr.)) and birch (Betula tortuosa Ledeb.) collected in the northern boreal forests of Central Siberia. The CWD samples were incubated at +5, +15 and +25 °C. The CO2 and CH4 fluxes showed strong correlations with temperature, moisture, decomposition stage and the type of wood’s rot. The temperature coefficient Q10 indicated higher temperature sensitivity of CO2 flux within the temperature interval from +5 to +15 °C than from +15 to +25 °C. Methane flux had higher temperature sensitivity within the interval from +15 to +25 °C. It was found that, in boreal forests, CWD of early decay stage can serve as a source of methane to the atmosphere when air temperatures increased above +15 °C. Strong positive correlation between CH4 production and CO2 emission indicated a biological source and supported findings on aerobic origin of the main process contributing to the CH4 flux from decomposing CWD.

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