A Study of Root Biomass in an Engeimann Spruce-Subalpine Fir Stand in Northern Utah

Biomass of roots in the top 6 inches of soil profile was measured . This weight was then used in a stepwise multiple regression to test correlations between root biomass and above ground merisurational parameters. Total biomass of all roots was 9822 ± 2810 pounds per acre oven dry. Spruce roots weighed 4417 ± 997 pounds per acre; of this spruce roots less than 0.125 inch diameter weighed 2023 ± 347 pounds per acre and biomass of spruce roots greater than 0.125 inch diameter was 2394 ± 8S3 pounds per acre. Total fir roots weighed Sl56 ± 2687 pounds per acre; of this roots less than 0.125 inch totaled 869 ± 181 pounds per acre and biomass of fir roots greater than 0.125 inch diameter was 4287 ± 2653 pounds per acre. Low r2 (0.11 to 0 .17) values were found and the parameters which showed the greatest predictive value were (dbh)2, dbh, basal area, (basal area)2, and height. The sampling design involved the pairing of trees over 4 inches diameter. Point density expressed as basal area was not useful in relating to root biomass with this sampling design

Expanding the scope of the crystallization-driven self-assembly of polylactide-containing polymers

We report the crystallization-driven self-assembly of diblock copolymers bearing a poly(L-lactide) block into cylindrical micelles. Three different hydrophilic corona-forming blocks have been employed: poly(4-acryloyl morpholine) (P4AM), poly(ethylene oxide) (PEO) and poly(N,N-dimethylacrylamide) (PDMA). Optimization of the experimental conditions to improve the dispersities of the resultant cylinders through variation of the solvent ratio, the polymer concentration, and the addition speed of the selective solvent is reported. The last parameter has been shown to play a crucial role in the homogeneity of the initial solution, which leads to a pure cylindrical phase with a narrow distribution of length. The hydrophilic characters of the polymers have been shown to direct the length of the resultant cylinders, with the most hydrophilic corona block leading to the shortest cylinders

Thermo-responsive Diblock Copolymer Worm Gels in Non-polar Solvents

Benzyl methacrylate (BzMA) is polymerized using a poly(lauryl methacrylate) macromolecular chain transfer agent (PLMA macro-CTA) using reversible addition–fragmentation chain transfer (RAFT) polymerization at 70 °C in n-dodecane. This choice of solvent leads to an efficient dispersion polymerization, with polymerization-induced self-assembly (PISA) occurring via the growing PBzMA block to produce a range of PLMA–PBzMA diblock copolymer nano-objects, including spheres, worms, and vesicles. In the present study, particular attention is paid to the worm phase, which forms soft free-standing gels at 20 °C due to multiple inter-worm contacts. Such worm gels exhibit thermo-responsive behavior: heating above 50 °C causes degelation due to the onset of a worm-to-sphere transition. Degelation occurs because isotropic spheres interact with each other much less efficiently than the highly anisotropic worms. This worm-to-sphere thermal transition is essentially irreversible on heating a dilute solution (0.10% w/w) but is more or less reversible on heating a more concentrated dispersion (20% w/w). The relatively low volatility of n-dodecane facilitates variable-temperature rheological studies, which are consistent with eventual reconstitution of the worm phase on cooling to 20 °C. Variable-temperature 1H NMR studies conducted in d26-dodecane confirm partial solvation of the PBzMA block at elevated temperature: surface plasticization of the worm cores is invoked to account for the observed change in morphology, because this is sufficient to increase the copolymer curvature and hence induce a worm-to-sphere transition. Small-angle X-ray scattering and TEM are used to investigate the structural changes that occur during the worm-to-sphere-to-worm thermal cycle; experiments conducted at 1.0 and 5.0% w/w demonstrate the concentration-dependent (ir)reversibility of these morphological transitions

Aqueous worm gels can be reconstituted from freeze-dried diblock copolymer powder.

Worm-like diblock copolymer nanoparticles comprising poly(glycerol monomethacrylate) (PGMA) as a stabilizer block and poly(2-hydroxypropyl methacrylate) (PHPMA) as a core-forming block were readily synthesized at 10% w/w solids via aqueous dispersion polymerization at 70 °C using Reversible Addition-Fragmentation chain Transfer (RAFT) chemistry. On cooling to 20 °C, soft transparent free-standing gels are formed due to multiple inter-worm interactions. These aqueous PGMA-PHPMA diblock copolymer worms were freeze-dried, then redispersed in water with cooling to 3-5 °C before warming up to 20 °C; this protocol ensures molecular dissolution of the copolymer chains, which aids formation of a transparent aqueous gel. Rheology, SAXS and TEM studies confirm that such reconstituted gels comprise formed PGMA-PHPMA copolymer worms and they possess essentially the same physical properties determined for the original worm gels prior to freeze-drying. Such worm gel reconstitution is expected to be highly beneficial in the context of various biomedical applications, since it enables worm gels to be readily prepared using a wide range of cell growth media as the continuous aqueous phase

Bi-fractional transforms in phase space

The displacement operator is related to the displaced parity operator through a two dimensional Fourier transform. Both operators are important operators in phase space and the trace of both with respect to the density operator gives the Wigner functions (displaced parity operator) and Weyl functions (displacement operator). The generalisation of the parity-displacement operator relationship considered here is called the bi-fractional displacement operator, O(α, β; θα, θβ). Additionally, the bi-fractional displacement operators lead to the novel concept of bi-fractional coherent states. The generalisation from Fourier transform to fractional Fourier transform can be applied to other phase space functions. The case of the Wigner-Weyl function is considered and a generalisation is given, which is called the bi-fractional Wigner functions, H(α, β; θα, θβ). Furthermore, the Q−function and P−function are also generalised to give the bi-fractional Q−functions and bi-fractional P−functions respectively. The generalisation is likewise applied to the Moyal star product and Berezin formalism for products of non-commutating operators. These are called the bi-fractional Moyal star product and bi-fractional Berezin formalism. Finally, analysis, applications and implications of these bi-fractional transforms to the Heisenberg uncertainty principle, photon statistics and future applications are discussed

Hydrogeology and Hydrochemistry of the East-Central Portion of The Salt Lake Valley, Utah, as Applied to Wellhead Protection in a Confined To Semiconfined Aquifer

The Safe Drinking Water Act includes provisions for state wellhead protection programs which address wellhead protection areas. In Utah, these areas are called drinking water source protection (DWSP) zones. Zones Two and Three are delineated according to analytical or numerical techniques, which are based on hydrogeological and time-of-travel data, as well as recharge information, accumulated through the use of hydrogeologic and hydrochemical techniques. The primary conclusions of this research are: 1) A fence diagram and site hydrostratigraphic diagram show that the hydrogeology is more complex than previously has been thought . The principal aquifer at the target well site comprises a sequence of mostly coarse-grained units interspersed with thinner fine-grained units. The supposedly unconfined shallow aquifer is confined in most parts of the valley, including the target well site. 2) The recovery rate of water levels in the monitor wells in response to pumping of the target well indicates that horizontal groundwater flow velocities are low at the target well site. X 3) Interpretation of major ions relative to the depth of uppermost open interval of the various sample wells indicates that the deeper of the three major water-bearing zones (below 300 to 350 feet [91 to 107 meters]) is not well connected to the upper two zones. 4) The chemical evolution of the water along the westernmost of three discrete flowpaths indicates a change from young calcium bicarbonate water to moderately mature sodium-sulfate water. 5) Sample waters recharged from the northern Wasatch Mountains have higher total-dissolved-solids (TDS) contents then sample waters recharged from the southern Wasatch Mountains . 6) The discrepancy between many of the δ18O, δD, and tritium data as to the probable recharge area(s) indicate that the sample wells must be evaluated on an individual basis regarding the source of recharge water. 7) The tritium data demonstrate that those wells located farthest out into the valley or having the deepest uppermost open interval furnish the lowest tritium values. 8) Based on the 14C dating technique , the groundwater at the target well site appears to be between 1300 and 5300 years old. 9) There is little risk of contamination at the target well site, in terns of the 15-year time-of-travel DWSP zone (Zone 3)

A Study of Root Biomass in an Engelmann Spruce-Subalpine Fir Stand in Northern Utah

Biomass of roots in the top 6 inches of soil profile was measured. This weight was then used in a stepwise multiple regression to test correlations between root biomass and above ground mensurational parameters. Total biomass of all roots was 9822 ± 2810 pounds per acre oven dry. Spruce roots weighed 4417 ± 997 pounds per acre; of this spruce roots less than 0.125 inch diameter weighed 2023 ± 347 pounds per acre and biomass of spruce roots greater than 0.125 inch diameter was 2394 ± 853 pounds per acre. Total fir roots weighed 5156 ± 2687 pounds per acre; of this roots less than 0.125 inch totaled 869 ± 181 pounds per acre and biomass of fir roots greater than 0.125 inch diameter was 4287 ± 2653 pounds per acre. Low r2 (0.11 to 0.17) values were found and the parameters which show­ed the greatest predictive value were (dbh)2, dbh, basal area, (basal area)2, and height. The sampling design involved the pairing of trees over 4 inches diameter. Point density expressed as basal area was not useful in relating to root biomass\u27with this sampling design