The Thermal Pressure and Energy–Volume Coefficients of Dimethyl Sulfoxide – Water Mixtures

1971 ◽  
Vol 49 (4) ◽  
pp. 611-617 ◽  
Author(s):  
Digby D. Macdonald ◽  
J. B. Hyne

Thermal pressure and energy–volume coefficients are reported for several DMSO–water mixtures over the temperature range 13–55 °C. The energy–volume coefficient at 25 °C is found to pass through a maximum at 0.3–0.4 mole fraction DMSO and this observation is rationalized in terms of maximization of intercomponent interactions. The relationship between the energy–volume coefficient and the cohesive energy density of the binary liquid system is examined. The temperature dependence of the thermal pressure coefficient is discussed in terms of the effect of temperature on the susceptibility of the entropy of DMSO–water mixtures to isothermal expansion.

1971 ◽  
Vol 49 (16) ◽  
pp. 2636-2642 ◽  
Author(s):  
Digby D. Macdonald ◽  
J. B. Hyne

Thermal pressure and energy–volume coefficients have been determined for various methyl alcohol – water and t-butyl alcohol – water mixtures at several temperatures in the range 19–55 °C. The energy–volume coefficient is found to pass through a maximum at 0.3–0.4 mole fraction methyl alcohol and 0.1 mole fraction t-butyl alcohol. This behavior is consistent with the average intermolecular distance passing through a minimum in both systems at the corresponding solvent compositions. The relationship between the energy–volume coefficient, the cohesive energy density, and the structure of aqueous binary systems is examined. The temperature dependence of the thermal pressure coefficient is discussed in terms of the effect of temperature on the susceptibility of the entropy of the two systems to isothermal expansion.


1973 ◽  
Vol 51 (12) ◽  
pp. 1885-1888 ◽  
Author(s):  
Ikchoon Lee ◽  
J. B. Hyne

The temperature dependence of the energy–volume coefficient of pure water and of aqueous potassium chloride solutions as a function of concentration over the temperature range 10–50 °C has been determined by direct measurement of constant volume thermal–pressure coefficient. The results show that a thermal anomaly exists in the energy–volume coefficient of aqueous solution in the temperature range 30–40 °C and becomes more pronounced as the concentration of solute is increased.


1973 ◽  
Vol 46 (2) ◽  
pp. 331-337 ◽  
Author(s):  
Hsiang Shih ◽  
P. J. Flory

Abstract The thermal expansivity α=V−1(∂V/∂T)p and thermal pressure coefficient γ=(∂p/∂T)v for poly(dimethylsiloxane) (PDMS), mol wt ≈ 105, have been determined accurately over the temperature ranges 20–207 and 24–161°, respectively. Characteristic parameters ν*, T*, and p* calculated from these results are compared with those for other polymers and for low molecular weight liquids. For PDMS, α is much larger and γ much smaller than for any other polymer. The characteristic pressure p* appears to be a more reliable index of the intermolecular energy than the cohesive energy density for this purpose. It is approximately the same for a polymer as for corresponding low molecular weight liquids. For PDMS and HMDS (hexamethyldisiloxane) p* assumes exceptionally low values of 341 and 358 J cm−3, respectively, which are duplicated only by the fluorocarbons (p* ≈ 360 J cm−3).


Author(s):  
Robert M. Glaeser

It is well known that a large flux of electrons must pass through a specimen in order to obtain a high resolution image while a smaller particle flux is satisfactory for a low resolution image. The minimum particle flux that is required depends upon the contrast in the image and the signal-to-noise (S/N) ratio at which the data are considered acceptable. For a given S/N associated with statistical fluxtuations, the relationship between contrast and “counting statistics” is s131_eqn1, where C = contrast; r2 is the area of a picture element corresponding to the resolution, r; N is the number of electrons incident per unit area of the specimen; f is the fraction of electrons that contribute to formation of the image, relative to the total number of electrons incident upon the object.


Author(s):  
D. T. Gauld ◽  
J. E. G. Raymont

The respiratory rates of three species of planktonic copepods, Acartia clausi, Centropages hamatus and Temora longicornis, were measured at four different temperatures.The relationship between respiratory rate and temperature was found to be similar to that previously found for Calanus, although the slope of the curves differed in the different species.The observations on Centropages at 13 and 170 C. can be divided into two groups and it is suggested that the differences are due to the use of copepods from two different generations.The relationship between the respiratory rates and lengths of Acartia and Centropages agreed very well with that previously found for other species. That for Temora was rather different: the difference is probably due to the distinct difference in the shape of the body of Temora from those of the other species.The application of these measurements to estimates of the food requirements of the copepods is discussed.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Rui Zhang ◽  
Yujie Meng ◽  
Hejia Song ◽  
Ran Niu ◽  
Yu Wang ◽  
...  

Abstract Background Although exposure to air pollution has been linked to many health issues, few studies have quantified the modification effect of temperature on the relationship between air pollutants and daily incidence of influenza in Ningbo, China. Methods The data of daily incidence of influenza and the relevant meteorological data and air pollution data in Ningbo from 2014 to 2017 were retrieved. Low, medium and high temperature layers were stratified by the daily mean temperature with 25th and 75th percentiles. The potential modification effect of temperature on the relationship between air pollutants and daily incidence of influenza in Ningbo was investigated through analyzing the effects of air pollutants stratified by temperature stratum using distributed lag non-linear model (DLNM). Stratified analysis by sex and age were also conducted. Results Overall, a 10 μg/m3 increment of O3, PM2.5, PM10 and NO2 could increase the incidence risk of influenza with the cumulative relative risk of 1.028 (95% CI 1.007, 1.050), 1.061 (95% CI 1.004, 1.122), 1.043 (95% CI 1.003, 1.085), and 1.118 (95% CI 1.028, 1.216), respectively. Male and aged 7–17 years were more sensitive to air pollutants. Through the temperature stratification analysis, we found that temperature could modify the impacts of air pollution on daily incidence of influenza with high temperature exacerbating the impact of air pollutants. At high temperature layer, male and the groups aged 0–6 years and 18–64 years were more sensitive to air pollution. Conclusion Temperature modified the relationship between air pollution and daily incidence of influenza and high temperature would exacerbate the effects of air pollutants in Ningbo.


Author(s):  
Jelle Wieme ◽  
Veronique Van Speybroeck

Thermal stress is present in metal–organic frameworks undergoing temperature changes during adsorption and desorption. We computed the thermal pressure coefficient as a proxy for this phenomenon and discuss the impact of thermal expansion mismatch.


2012 ◽  
Vol 7 (6) ◽  
pp. 562-571 ◽  
Author(s):  
Roger Giner-Sorolla

The current crisis in psychological research involves issues of fraud, replication, publication bias, and false positive results. I argue that this crisis follows the failure of widely adopted solutions to psychology’s similar crisis of the 1970s. The untouched root cause is an information-economic one: Too many studies divided by too few publication outlets equals a bottleneck. Articles cannot pass through just by showing theoretical meaning and methodological rigor; their results must appear to support the hypothesis perfectly. Consequently, psychologists must master the art of presenting perfect-looking results just to survive in the profession. This favors aesthetic criteria of presentation in a way that harms science’s search for truth. Shallow standards of statistical perfection distort analyses and undermine the accuracy of cumulative data; narrative expectations encourage dishonesty about the relationship between results and hypotheses; criteria of novelty suppress replication attempts. Concerns about truth in research are emerging in other sciences and may eventually descend on our heads in the form of difficult and insensitive regulations. I suggest a more palatable solution: to open the bottleneck, putting structures in place to reward broader forms of information sharing beyond the exquisite art of present-day journal publication.


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