Differential Pressure, P_D, Capital Parameter in the Determination of Cardiac Health and Prominent Kinetic Indicator of Drugs in the Blood

Background: this work is a suite of previous articles where it has been demonstrated that if the differential pressure remains constant, it allows when it is multiplied by cardiac frequency to determine the volumic cardiac power (KUNYIMA equation). Also it has afforded to calculate differential enthalpy ( that is exothermic energy in ejection fraction. In KUNYIMA Formula the differential pressure has allowed to assess in satisfactory way one part of total energy from cellular metabolism (Keith-Flack node) which enable the heart blood to circulate in the organism. In KUNYIMA relations, made possible the calculation of cardiac exergetic yield nowadays unrecognized by researchers, different from volumic yield defined by ejection fraction. This cardiac exergetic yield has been assimilated to the heart longevity. Aim and objective: this work gives in detail mathematical useful expressions, rational approaches to be followed when differential pressure substantially changes, for example when the blood contains an injected drug at initial concentration and when the kinetic of this drug should be followed. Methodology: Calculations have been our methodology using compartmental analysis. Results: It is shown hereby the use of differential equations in the determination of kinetic parameters Conclusion: Physical Cardiochemistry is improved with new theory.

Energy Conservation Potential of Economizer Controls Using Optimal Outdoor Air Fraction Based on Field Study

In commercial buildings, HVAC systems are becoming a primary driver of energy consumption, which already account for 45% of the total building energy consumption. In the previous literature, researchers have studied several energy conservation measures to reduce HVAC system energy consumption. One of the effective ways is an economizer in air-handling units. Therefore, this study quantified the impact of the outdoor air fraction by economizer control type in cooling system loads based on actual air-handling unit operation data in a hospital. The optimal outdoor air fraction and energy performance for economizer control types were calculated and analyzed. The result showed that economizer controls using optimal outdoor air fraction were up to 45% more efficient in cooling loads than existing HVAC operations in the hospital. The energy savings potential was 6–14% of the differential dry-bulb temperature control, 17–27% of the differential enthalpy control, 8–17% of the differential dry-bulb temperature and high-limit differential enthalpy control, and 16–27% of the differential enthalpy and high-limit differential dry-bulb temperature control compared to the no economizer control. The result of this study will contribute to providing a better understanding of economizer controls in the hospital when the building operates in hot-humid climate regions.

A Novel Approach for the Determination of Sorption Equilibria and Sorption Enthalpy Used for MOF Aluminium Fumarate with Water

Adsorption chillers offer an environmentally friendly solution for the valorisation of waste or solar heat for cooling demands. A recent application is high efficiency data centre cooling, where heat from CPUs is used to drive the process, providing cooling for auxiliary loads. The metal organic framework aluminium fumarate with water is potentially a suitable material pair for this low temperature driven application. A targeted heat exchanger design is a prerequisite for competitiveness, requiring, amongst other things, a sound understanding of adsorption equilibria and adsorption enthalpy. A novel method is employed for their determination based on small isothermal and isochoric state changes, applied with an apparatus developed initially for volume swing frequency response measurement, to samples with a binder-based adsorbent coating. The adsorption enthalpy is calculated through the Clausius–Clapeyron equation from the obtained slopes of the isotherm and isobar, while the absolute uptake is determined volumetrically. The isotherm confirms the step-like form known for aluminium fumarate, with a temperature dependent inflection point at p rel ≈ 0.25, 0.28 and 0.33 for 30 °C, 40 °C and 60 °C. The calculated differential enthalpy of adsorption is 2.90 ± 0.05 MJ/kg (52.2 ± 1.0 kJ/mol) on average, which is about 10–15% higher than expected by a simple Dubinin approximation.

A novel approach for the determination of sorption equilibria and sorption enthalpy used for MOF aluminium fumarate with water

Adsorption chillers offer an environmentally friendly solution for the valorisation of waste or solar heat for cooling demands. A recent application is high efficiency data centre cooling, where heat from CPUs is used to drive the process, providing cooling for auxiliary loads. The metal organic framework aluminium fumarate with water is potentially a suitable material pair for this low temperature driven application. A targeted heat exchanger design is a prerequisite for competitiveness, requiring, amongst other things, a sound understanding of adsorption equilibria and adsorption enthalpy. A novel method is employed for their determination based on small isothermal and isochoric state changes, applied with an apparatus developed initially for volume swing frequency response measurement, to samples with a binder-based adsorbent coating. The adsorption enthalpy is calculated through the Clausius–Clapeyron equation from the obtained slopes of the isotherm and isobar, while the absolute uptake is determined volumetrically. The isotherm confirms the step-like form known for aluminium fumarate, with a temperature dependent inflection point at prel ≈ 0.25, 0.28 and 0.33 for 30 °C, 40 °C and 60 °C. The calculated differential enthalpy of adsorption is 2.90 ± 0.05 MJ/kg (52.2 ± 1.0 kJ/mol) on average, which is about 10–15% higher than expected by a simple Dubinin approximation.

Isotherms and thermodynamic properties of water adsorption in ‘Cumari-do-Pará’ pepper seeds

ABSTRACT Studies related to water sorption in seeds are essential for the design and optimization of storage systems. The objective of this research was to determine and model the adsorption isotherms and calculate the latent heat of water vaporization, differential enthalpy and entropy, the isokinetic theory and Gibbs free energy for ‘Cumari-do-Pará’ pepper seeds. The equilibrium moisture contents were obtained by the static gravimetric method at temperatures of 30, 35 and 40 °C and water activities between 0.290 and 0.900 (decimal). The Chen-Clayton model is the one that best represents the water adsorption isotherms in ‘Cumari-do-Pará’ pepper seeds under the studied conditions, with 9.94% mean relative error, 0.40 mean estimated error and random distribution of residuals. The latent heat of vaporization ranged from 2,555.669 to 3,162.180 kJ kg-1. The enthalpy, entropy and Gibbs free energy increase with the reduction in the equilibrium moisture content of the seeds. The isokinetic theory is valid for the adsorption process.

Hygroscopic Behavior and Thermodynamic Properties of Ziziphus joazeiro Mart. Kernel Flour

The hygroscopic and thermal behavior of kernel flour from Ziziphus joazeiro fruits were investigated. Adsorption isotherms were obtained at temperatures of 293, 303 and 313 K and adjusted to GAB, Oswin and Peleg models. The best fit of the experimental data was obtained with the GAB model with R² values> 0.994 and mean percentage deviation P <10%. The isotherms obtained were sigmoidal type II. Isosteric heat and other thermodynamic properties were calculated as a function of moisture content. Adsorption isosteric heat decreased exponentially with increasing moisture content and differential entropy increased with moisture content, while differential enthalpy decreased. The theory of compensation confirmed that these properties are dependent on moisture content. The isotherms presented a spontaneous and enthalpy process.

Low Temperature Calorimetry Coupled with Molecular Simulations for an In-Depth Characterization of the Guest-Dependent Compliant Behaviour of MOFs

In this study adsorption microcalorimetry is employed to monitor the adsorption of four probes (argon, oxygen, nitrogen and carbon monoxide) on a highly flexible mesoporous metal-organic framework (DUT-49, DUT = Dresden University of Technology), precisely measuring the differential enthalpy of adsorption alongside high-resolution isotherms. This experimental approach combined with force field Monte Carlo simulations reveals distinct pore filling adsorption behaviours for the selected probes, with argon and oxygen showing abrupt adsorption in the open pore form of DUT-49, in contrast with the gradual filling for nitrogen and carbon monoxide. A complex structural transition behaviour of DUT-49 observed upon nitrogen adsorption is elucidated through an isotherm deconvolution in order to quantify the fraction of the open pore, contracted pore and intermediate pore forms that coexists at a given gas pressure. Finally, the heat flow measured during the guest-induced structural contraction of DUT-49 allowed an exploration of complex open-contracted pore transition energetics, leading to a first assessment of the energy required to induce this spectacular structural change.

Low Temperature Calorimetry Coupled with Molecular Simulations for an In-Depth Characterization of the Guest-Dependent Compliant Behaviour of MOFs

In this study adsorption microcalorimetry is employed to monitor the adsorption of four probes (argon, oxygen, nitrogen and carbon monoxide) on a highly flexible mesoporous metal-organic framework (DUT-49, DUT = Dresden University of Technology), precisely measuring the differential enthalpy of adsorption alongside high-resolution isotherms. This experimental approach combined with force field Monte Carlo simulations reveals distinct pore filling adsorption behaviours for the selected probes, with argon and oxygen showing abrupt adsorption in the open pore form of DUT-49, in contrast with the gradual filling for nitrogen and carbon monoxide. A complex structural transition behaviour of DUT-49 observed upon nitrogen adsorption is elucidated through an isotherm deconvolution in order to quantify the fraction of the open pore, contracted pore and intermediate pore forms that coexists at a given gas pressure. Finally, the heat flow measured during the guest-induced structural contraction of DUT-49 allowed an exploration of complex open-contracted pore transition energetics, leading to a first assessment of the energy required to induce this spectacular structural change.

Thermodynamic properties of Anacardium humile St. Hil. (cajuzinho-do-cerrado) achenes

The cajuzinho-do-cerrado is a native species of the cerrado of great potential of use and is threatened of extinction. The aim of this study was to determine and evaluate the thermodynamic properties of Anacardium humile St. Hil. achenes from the different hygroscopic equilibrium points according to the moisture content. To obtain the isotherms, the indirect static method was used at temperatures of 10, 20, 30 and 40 °C and for moisture contents of 13.4, 11.1, 8.7 and 5.3% dry basis (db). The Copace model was used to describe the hygroscopic equilibrium of the achenes. The thermodynamic properties are influenced by the moisture content because the latent heat of vaporization of the water of the achenes increases with the decrease in the equilibrium moisture content, varying between 3,035.63 and 2,510.80 kJ kg-1 for moisture contents of 4.51 to 13.4% db, respectively. The differential enthalpy and entropy are closely related to the moisture content of the achenes. The isokinetic temperature of 304.67 K denotes the linear chemical compensation between the differential enthalpy and entropy of the Anacardium humile St. Hil. achenes, and the desorption process is controlled by enthalpy.

Brassinosteroid phytochormones as regulators of plant growth and modulators of pesticide and fertilizer activity

The mode of action of agrochemicals on plants implies the totality of their effect on plant metabolism, growth and development. The effects of different doses of 24-epibrassinolide (24-EBL) as a class of brassinosteroid phytohormones on growth and other physiological processes in maize plants during different development stages are reviewed in order to assess the influence of these agrochemicals on various factors determining the yield of maize as an important agricultural crop. In addition, several examples are given of the effects of these phytohormones on other crops, fruits and vegetables, in terms of their effect on yield, yield quality, and increase in crop resistance to some types of stress. Own results are discussed in the context of other literature data. Abbreviations: 24-EBL: 24-epibrassinolide; BRs: brassinosteroids; PCZ: propiconazole; Chl a: chlorophyl a; RFW (g g-1): relative fresh weight of different organs (R: radicle; P: plumule; RoS: rest of seed); TDW, TFW (g): total dry and fresh weight of plants; V root (ml): root volume; LMR, RMR, SMR (g g-1): relative dry weight of plant parts (leaves, roots, stem); dH (J mol-1 K-1): differential enthalpy of different parts (R: radicle; P: plumule; RoS: rest of seed) of 25 maize seedlings exposed to T(reatments) of different molar concentrations of 24-EBL; ?G105 (J mol-1 K-1) differential Gibbs free energy of total maize plant and their parts (R: roots; L: leaves; S: stem) assesed at 105 0C; ZP434, ZP704, ZP505: maize hybrids; Fv/Fm, , Fv/F0, ??S2, qP, NPQ, RFD730 (all in relative units), ETR (?mol electrons m-2 s-1): different Chl a fluorescence parameters; Pphy, Pi: phosphorus bond to phytic acid and free phosphorus available to many cellular biochemical reactions; GSH: reduced form of gluthathyone; K, Ca, Fe, Mg, Zn, Si: different chemical elements.