Effect of Unsaturation, Cyclization and Isotopic Substitution on Critical Demixing Temperatures

The demixing curves in binary systems of nitromethane with 11 1-alkenes, 6 cycloalkanes and 2 cycloalkenes, and of CD8COCD3 with 5 n.alkanes were measured. Critical demixing temperatures: a) are additively affected by unsaturation and cyclization in the first group of systems; b) are increased by a constant amount in the second group, in comparison to the corresponding systems containing CH3COCH3

Thermophysics of metal alkanoates IV. Heat capacities and thermodynamic properties of potassium 2-methylpropanoate

The molar heat capacity of potassium 2-methylpropanoate, (CH3)2CHCO2K, has been measured between 8 and 350 K by adiabatic calorimetry, and found to be normal. The corresponding thermodynamic functions have been calculated. The values found at 298.15 K for Cp, m(T)/R, {Smo(T) - Smo(0)}/R, {Hmo(T) - Hmo(0)}/R, and {Gmo(T) - Hmo(0)}/RT are 20.08, 23.14, 3457.3 K, and -11.546, respectively.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24966/1/0000393.pd

Thermophysics of metal alkanoates VII. Heat capacities and thermodynamic properties of potassium n-butanoate

The subambient heat-capacity curve of potassium n-butanoate as determined by adiabatic equilibrium calorimetry is characterized by a "bifurcated" transition whose "peaks" occur at 123.85 and 142.3 K. The corresponding (Cp, m/R)max, [Delta]trsHmo/R, and [Delta]trsSmo/R, values are 24.1, 23.85; 49.3 K, 32.5 K; and 0.400, 0.226, respectively. Smoothed thermodynamic functions are provided in tabular form from 10 to 350 K.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26886/1/0000452.pd

Thermophysics of metal alkanoates II. Heat capacities and thermodynamic properties of sodium propanoate

The heat capacity of sodium propanoate has been measured from 9 to 580 K by adiabatic calorimetry and considerable metastability noted between 60 and 215 K. Values at 298.15 K of Cp,m/R, Smo/R, "Hmo-Hmo(0)'/R, and "Gmo-Hmo(0)'/RT are 16.16, 18.29, 2809.1 K, and -8.872. Comparisons with d.s.c. results and other reported phase behavior are provided.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25432/1/0000882.pd

Thermophysics of metal alkanoates I. Heat capacities and thermodynamic properties of sodium methanoate and ethanoate

The heat capacities of two sodium alkanoates have been studied by adiabatic calorimetry. Earlier measurements from this laboratory on sodium methanoate between 5 and 350 K are supplemented from 300 K to melting. Sodium ethanoate ismeasured from 7 through 350 K; the results differ markedly from those reported by Strelkov in that we find the 21 K transition peak is much larger and the higher temperature values are 15 to 20 per cent higher and in good accord with reported d.s.c. studies at still higher temperatures. We estimate [Delta]traSmo/R of the 21 K peak to be about 1.5 although no isostructural lattice contribution is available. Even with adjuvant X-ray diffraction results by Hsu and Nordman the mechanism of the transition has not been identified. The 298.15 K values of Cp,m/R, Smo/R, {Hmo-Hmo(0)}/R and {Gmo-Hmo(0)}/RT are 12.127, 16.610, 2308.1 K, and -8.868 for form II CH3COONa.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25417/1/0000866.pd

Sink or swim? Modernization of mussel farming methods may negatively impact established seabird communities

Marine aquaculture is the fastest growing sector of global food production and is projected to increase to meet future demand. Expansion and modernization of cultivation methods are needed to reach this target but a cost-benefit evaluation for biodiversity conservation is required to achieve sustainable aquaculture practices. We assess drivers of avian richness and abundance in a long-established seabird community present in a series of longline mussel farms in Italy and in response to a recent modernization process in the farming methodology. Over 2 years (24 surveys) we detected a remarkable diversity (15 species in 5 families) and abundance (n = 5858) of birds, of which 40% (n = 6) are regarded as species of international conservation importance. Our models highlighted that the strongest driver explaining variation in abundance and richness across sites was the type of buoy and the associated cultivation method applied. The older and fast-declining double headrope design, offered greater stability for birds to rest. Conversely, the newer and mechanizable single headrope design dominant method in our study site and projected to replace the older system, was unsuitable for birds. Our findings confirm the function of mussel farms as a sort of marine protected area where low anthropogenic disturbance, higher prey availability and suitable artificial structures promote the establishment of seabird communities with minimal impacts on harvest. However, we suggest that potential modernization of farming methods, important to meet future human demand, needs to be carefully assessed and compensated for, particularly where long-established seabird communities have formed in response to such practices

Thermophysics of metal alkanoates VI. Heat capacities and thermodynamic properties of lithium n-pentanoate and n-heptanoate

The adiabatic calorimetric study (at 5 to 350 K) of lithium n-pentanoate and n-heptanoate proved that solid-state transitions occur at Ttrs/K = 209.31 and 319.06 in the former salt, and at Ttrs/K = 317.08 in the latter one. Concerning n-pentanoate, the discontinuous (predominantly first-order) crystal-to-crystal transition at 209.31 K is followed almost immediately by a broad and diffused "hump" (with a maximum at 319.06 K), which stretches over a temperature range of about 110 K, and is apparently related to the occurrence of a gradual higher-order, possibly second-order) transformation. Concerning n-heptanoate, the nature and order of its single transition should be the same as suggested for the lower-temperature transformation of the shorter homolog. At the transition temperatures, the values of Cp,m/R, [Delta]trsSm/R, and [Delta]trsHm/R are 27.4, 0.39, and 80 K; and 32.9, 1.94, and 330.1 K, for the 209.31 K and 319.06 K transitions of lithium n-pentanoate, respectively; and 7800, 2.228, and 702.44 K for lithium n-heptanoate. Thermodynamic functions are tabulated at selected temperatures for both samples.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25966/1/0000032.pd