Search results for "Solutions"
showing 10 items of 757 documents
Synthesis, crystal structure and molecular conformation of the tBuCO-D,L-Ala-Δz-Phe-NhiPr α,β-unsaturated dipeptide
2009
The crystal structure of the tBuCO-D,L-Ala-delta Z-Phe-NHiPr dipeptide has been solved by X-ray diffraction. The peptide crystallizes in monoclinic space group P2(1)/c with a = 13.445 (3) A, b = 35.088 (4) A, c = 14.755 (3) A, beta = 116.73 (1) degree, Z = 12 and dc = 1.151 g.cm-3. The three independent molecules per asymmetric unit accommodate a beta II-folded conformation, but only one of them contains the typical i + 3----i interaction characterizing a beta-turn. In the other two molecules, the N...O distance exceeds 3.2 A, a value generally considered the upper limit for hydrogen bonds in peptides. In solution, the beta II-turn conformation is largely predominant.
Studies of network organization and dynamics of e-beam crosslinked PVPs: From macro to nano
2012
Abstract In this work the influence of poly(N-vinyl pyrrolidone) (PVP) concentration in water on the organization and dynamics of the corresponding macro-/nanogel networks has been systematically investigated. Irradiation has been performed at the same irradiation dose (within the sterilization dose range) and dose rate. In the selected irradiation conditions, the transition between macroscopic gelation and micro-/nanogels formation is observed just below the critical overlap concentration (∼1 wt%), whereas the net prevalence of intra-molecular over inter-molecular crosslinking occurs at a lower polymer concentration (below 0.25 wt%). Dynamic–mechanical spectroscopy has been applied as a cl…
Heat capacities of butanol and pentanol in aqueous dodecyltrimethylammonium bromide solutions
1987
Heat capacities of the ternary systems water-dodecyltrimethylammonium bromide (DTAB)-butanol and water-DTAB-pentanol were measured at 25°C. The standard partial molar heat capacities of pentanol in micellar solutions show a maximum at about 0.35 mol-kg−1 DTAB that has been attributed to a micellar structural transition. This maximum tends to vanish by increasing the alcohol concentration and by decreasing the alcohol alkyl chain length; in the case of butanol it was not detected. The behavior of the standard partial molar heat capacities of alcohols in micellar solutions in the region above the cmc and below the structural transition was explained using a previously reported mass-action mod…
Effect of nanoaquacitrates on physiological parameters of Fodder Galega infected with phytoplasma
2018
The laboratory experiments have been found that so aking seeds Galega orientalis L. (Fodder galega) in nanoaquacitrates solutions of Mn (10 and 20 mg/dm 3), Mo (4 mg/dm3) and Mg (2 and 4 mg/dm3), has been lead to germination energy rise, while Mn( 10 and 20 mg/dm3) and Mo (4 mg/dm3) concentrations has been influenced germinating ability. At the same time, the soaking seeds in solution of nanoaquacitrates Mn (20 mg/dm3) had the biggest stimulatory effect on the accumulation 7 daily sprouts mass (on 18%). It has been shown that s oaking seeds in nanoparticles Mn and Mo solutions leads to the increase of catalase activities (especially under the influence of manganese) and peroxidase activitie…
Copper Octacarboxyphthalocyanine Aggregation in Buffered Solutions
2008
Results of spectral UV-Vis absorption investigations on association of copper octa-carboxyphthalocyanine, CuPcOC, are reported. Influence of pH on association is discussed. In pH < 5.5 only ag gre gates are present. Monomer appears above pH = 5.5 and at pH Greater-than or equal to 6.2 only monomeric Pc forms exist. CuPcOC exhibits higher tendency to wards association in phosphate buffer solutions than in redistilled water. In pH 5.9–6.0 monomers, dimers and trimers coexist in equilibrium in 1.0×10–6 – 1.2×10–5 mol/dm3 concentration range at 25°C. The average assembling number n = 3 was determined for pH 5.6, 5.9 and 6.0 solutions. The spectrum of aggregate was calculated with two maxima at …
Value Co-Creation Opportunities: Managerial Transformation of Digitisation Risks into Success Factors
2018
This chapter examines the challenges and risks managers in the healthcare sector perceive in relation to the development and implementation of digitised services in a healthcare case organisation. Using data collected from managers, focus group interviews and observation method within the case organisation, the authors present an analysis that demonstrates that the risks and success factors that influence the development and implementation of digital healthcare services are related to (1) setting a clear digital strategy and implementation plan, (2) integration of digital services with the overall process and ICT, (3) committed resources and engagement of personnel, and (4) the organisation…
Studies of network structure and dynamics of e-beam crosslinked PVPs: From macro to nano
2011
Much interest has been paid to develop a variety of radiation-crosslinked hydrated polymeric materials, which swell in water but do not dissolve, as biocompatible materials used for wound healing, drug delivery system, surface-coating material for medically used devices, etc. With the aim of establishing design rules to produce hydrogels of controlled size at the nanoscale and desired internal network structure using conventional electron accelerators and set-ups, here we attempt a description in terms of structural and dynamic properties of polymer networks generated through e-beam irradiation of aqueous solutions of the same model polymer, a commercial grade poly(N-vinyl-pyrrolidone), sub…
Préface Special Issue 'The Future of Agricultural Landscapes' part 1
2020
Préface de Advances in Ecological Research, Volume 63, the latest release in this ongoing series includes specific chapters on Tropical Ecosystems in the 21st Century. Chapters in this volume cover topics such as Landscape-scale expansion of agroecology to enhance natural pest control: a systematic review and Ecosystem services and the resilience of agricultural landscapes
A Side-by-Side Single Sex Age-Structured Human Population Dynamic Model: Exact Solution and Model Validation
2008
A side-by-side single sex age-structured population dynamic model is presented in this paper. The model consists of two coupled von Foerster-McKendrick-type quasi-linear partial differential equations, two initial conditions, and two boundary conditions. The state variables of the model are male and female population densities. The solutions of these partial differential equations provide explicit time and age dependence of the variables. The initial conditions define the male and female population densities at the initial time, while the boundary conditions compute the male and female births at zero-age by using fertility rates. The assumptions of the nontime-dependence of the death and fe…
Generalized curved beam on elastic foundation solved by Transfer Matrix Method
2011
A solution of space curved bars with generalized Winkler soil found by means of Transfer Matrix Method is presented. Distributed, concentrated loads and imposed strains are applied to the beam as well as rigid or elastic boundaries are considered at the ends. The proposed approach gives the analytical and numerical exact solution for circular beams and rings, loaded in the plane or perpendicular to it. A well-approximated solution can be found for general space curved bars with complex geometry. Elastic foundation is characterized by six parameters of stiffness in different directions: three for rectilinear springs and three for rotational springs. The beam has axial, shear, bending and tor…