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181.
A temperature-dependent integrated kinetics for the overall process of photosynthesis in green plants is discussed. The C4 plants are chosen and in these plants, the rate of photosynthesis does not depend on the partial pressure of O2. Using some basic concepts like chemical equilibrium or steady state approximation, a simplified scheme is developed for
both light and dark reactions. The light reaction rate per reaction center (R′
1) in thylakoid membrane is related to the rate of exciton transfer between chlorophyll neighbours and an expression is formulated
for the light reaction rate R′
1. A relation between R′
1 and the NADPH formation rate is established. The relation takes care of the survival probability of the membrane. The CO2 saturation probability in bundle sheath is also taken into consideration. The photochemical efficiency (ϕ) is expressed in terms of these probabilities. The rate of glucose production is given by R
glucose = (8/3)(R′
1
v
L
)ϕ(T)
g
(T) ([G3P]/[P
i]2
leaf)SS
Q
G3P→glucose where g is the activity quotient of the involved enzymes, and G3P represent glycealdehyde-3-phosphate in steady state. A Gaussian
distribution for temperature-dependence and a sigmoid function for de-activation are incorporated through the quotient g. In general, the probabilities are given by sigmoid curves. The corresponding parameters can be easily determined. The theoretically
determined temperature-dependence of photochemical efficiency and glucose production rate agree well with the experimental
ones, thereby validating the formalism. 相似文献
182.
183.
E. Milford Rice B. K. Datta Roy G. R. Clark W. H. King C. F. Jablonski und S. G. Abramowitsch 《Fresenius' Journal of Analytical Chemistry》1943,126(5):201-203
Ohne Zusammenfassung 相似文献
184.
Roxana Rahmati Virinder Sidhu Rosita Nunez Rupali Datta Dibyendu Sarkar 《Molecules (Basel, Switzerland)》2022,27(21)
Over the past several decades, the value of drinking water treatment residuals (WTRs), a byproduct of the coagulation process during water purification, has been recognized in various environmental applications, including sustainable remediation of phosphorus (P)-enriched soils. Aluminum-based WTRs (Al-WTRs) are suitable adsorbent materials for P, which can be obtained and processed inexpensively. However, given their heterogeneous nature, it is essential to identify an easily analyzable chemical property that can predict the capability of Al-WTRs to bind P before soil amendment. To address this issue, thirteen Al-WTRs were collected from various geographical locations around the United States. The non-hazardous nature of the Al-WTRs was ascertained first. Then, their P adsorption capacities were determined, and the chemical properties likely to influence their adsorption capacities were examined. Statistical models were built to identify a single property to best predict the P adsorption capacity of the Al-WTRs. Results show that all investigated Al-WTRs are safe for environmental applications, and oxalate-extractable aluminum is a significant indicator of the P adsorption capacity of Al-WTRs (p-value = 0.0002, R2 = 0.7). This study is the first to report a simple chemical test that can be easily applied to predict the efficacy of Al-WTRs in binding P before their broadscale land application. 相似文献
185.
Phosphorus and heavy metals are washed off and transported with stormwater runoff to nearby surface water bodies resulting in environmental and human health risks. Catch basins remain one of the primary gateways through which stormwater runoff and pollutants from urban areas are transported. Retrofitting catch basins to enhance their phosphorus and heavy metal removal can be an effective approach. In this study, aluminum-based water treatment residual (WTR, a non-hazardous byproduct of the water treatment process) was granulated via a green method to serve as a sustainable filter material, called WTR granules, for enhancing the capabilities of catch basins to remove phosphorus and heavy metals. The WTR granules were field tested in a parking lot in Hoboken, New Jersey. Twelve storm events were monitored. The results showed that the WTR granules significantly (p < 0.05) reduced dissolved P, Cu, and Zn, as well as total P, Cu, Pb, and Zn concentrations in stormwater runoff without signs of disintegration. No flooding or water ponding was observed during the implementation. Results suggest the WTR granules are an inexpensive, green filter material that can be used for retrofitting catch basins to remove phosphorus and heavy metals effectively. 相似文献
186.
187.
The measurements of the ΔI = 1 part of the parity violating nuclear force when combined with information on neutral current couplings from neutrino
scattering and pion production experiments allow an estimate of the isoscalar admixture in the neutral current if it has a
vector axial-vector structure has been shown. 相似文献
188.
Anasuya Datta C. M. Srivastava N. Venkataramani 《Physica C: Superconductivity and its Applications》1993,210(3-4):408-412
We have examined the DC electrical resistivity of RE-123 superconductors (where RE is a rare earth element) on the basis of a model of correlated electron transfer arising from the electron-phonon interaction. The small polaron stabilization energy (εp) has been obtained from the fitting of the normal state resistivity data. A correlation between the lattice parameters of the unit cell and εp has been observed which is explained on the basis of fermiology. 相似文献
189.
190.
Sambhu N. Datta 《Journal of Chemical Sciences》2007,119(5):351-356
The retarded interaction between an electron and a spin-0 nucleus, that has been derived from electro-dynamical perturbation
theory is discussed here. A brief account of the derivation is given. The retarded form is correct through order v
2/c
2. Use of the relative coordinates leads to an effective one-electron operator that can be used through all orders of perturbation
theory. A few unitary transformations give rise to the interaction that is valid in the non-relativistic limit. 相似文献