Aerosol transport in a bifurcating tube at cyclic flow

Branching tube flow is a common feature of many fields of science and technology, and occurs both in animate and inanimate systems [1]. The transport of aerosol particles is of particular importance in industrial flow networks but also for the respiratory tree [2]. In this analysis a 3-D numerical study is performed to investigate transport and deposition of aerosol particles in branching tubes. Bifurcation tubes designed according to Hess-Murray law [3] but with different branching angles are analyzed. This study covers cyclic flow conditions at frequencies of 0.25 Hz, 0.50 Hz and 0.75 Hz, Stokes numbers ranging between 0.03 and 0.25, and Reynolds numbers up to 3000.

Scaling laws and thermodynamic analysis for vascular branching of microvessels

When blood flows through small vessels, the two-phase nature of blood as a suspension of red cells (erythrocytes) in plasma cannot be neglected, and with decreasing vessel size, a homogeneous continuum model become less adequate in describing blood flow. Following the Haynes’ marginal zone theory, and viewing the flow as the result of concentric laminae of fluid moving axially, the present work provides models for fluid flow in dichotomous branching composed by larger and smaller vessels, respectively. Expressions for the branching sizes of parent and daughter vessels, that provides easier flow access, are obtained by means of a constrained optimization approach using the Lagrange multipliers. This study shows that when blood behaves as a Newtonian fluid, Hess – Murray law that states that the daughters-to-parent diameter ratio must equal to 2^(-1/3) is valid. However, when the nature of blood as a suspension becomes important, the expression for optimum branching diameters of vessels is dependent on the separation phase lengths. It is also shown that the same effect occurs for the relative lengths of daughters and parent vessels. For smaller vessels (e. g., arterioles and capillaries), it is found that the daughters-to-parent diameter ratio may varies from 0,741 to 0,849, and the daughters-to-parent length ratio varies from 0,260 to 2,42. For larger vessels (e. g., arteries), the daughters-to-parent diameter ratio and the daughters-to-parent length ratio range from 0,458 to 0,819, and from 0,100 to 6,27, respectively. In this paper, it is also demonstrated that the entropy generated when blood behaves as a single phase fluid (i. e., continuum viscous fluid) is greater than the entropy generated when the nature of blood as a suspension becomes important. Another important finding is that the manifestation of the particulate nature of blood in small vessels reduces entropy generation due to fluid friction, thereby maintaining the flow through dichotomous branching vessels at a relatively lower cost.

Study of the miscibility and thermodynamics of cellulose diacetate-poly(vinyl pyrrolidone) blends

The miscibility of blends of cellulose diacetate (CDA) and poly(vinyl pyrrolidone) (PVP) was extensively studied by means of differential thermal analysis and dynamic mechanical thermal analysis, tensile test, measuring viscosity of diluted and concentrated solutions of blends in acetone-ethanol mixture and morphological observations. A single glass transition temperature is observed, which is intermediate between the glass transition temperatures associated with each component and depends on composition. A synergism in mechanical properties of blends was found. The absolute viscosity and the intrinsic viscosity of solutions of blends are much higher than the weight average values of solutions of CDA and PVP. Optically clear and thermodynamically stable films were formed in the composition range of CDA/PVP = 100/0 to 50/50w/w. Fourier transform infrared was used to investigate the nature of CDA-PVP interaction. Hydrogen bonds were formed between hydroxyl groups of CDA and carbonyl groups of PVP. Heats of solutions of CDA/PVP blends and their mechanical mixtures were measured by using a calorimeter. Mixing enthalpy obtained with Hess's law approach was used to quantify interaction parameters of this blending system. It was found that mixing enthalpies and interaction parameters were negative and composition dependent. (C) 1997 Elsevier Science Ltd.

Relative basicities of free base porphyrins; understanding the role of macrocyclic distortion

Porphyrins have been the center of numerous investigations in different areas of chemistry, geochemistry, and the life sciences. In nature the conformation of the porphyrin macrocycle varies, depending on the function of its apoenzyme. It is believed that the conformation of the porphyrin ring is necessary for the enzyme to achieve its function and modify its reactivity. It is important to understand how the conformation of the porphyrin ring will influence its properties. ^ In synthetic porphyrins particular conformations and ring deformations can be achieved by peripheral substitution, metallation, core substitution, and core protonation among other alterations of the macrocycle. The macrocyclic distortions will affect the ring current, the ability of pyrroles to intramolecularly hydrogen bond and the relative basicity of each of the porphyrins. To understand these effects different theoretical models are used. The ground state structure of each of 19 free base porphyrins is determined using molecular mechanics (MM+) and semiempirical methods (PM3). The energetics of deformation of the macrocyclic core is calculated by carrying out single point energy calculations for the conformation achieved by each synthetic compound. Enthalpies of solution and enthalpies of protonation of 10 porphyrins with varying degrees of macrocyclic deformation and varying electron withdrawing groups in the periphery are determined using solution calorimetry. Using Hess's Law, the relative basicity of each of the different free base porphyrins is calculated. NMR results are described, including the determination of free energies of activation of ring tautomerization and hydrogen bonding for several compounds. It was found that in the absence of electronic effects, the greater macrocyclic deformation, the greater the basicity of the porphyrins. This basicity is attenuated by the presence of electron withdrawing groups and ability to of the macrocycle to intramolecularly hydrogen bond. ^

Relative basicities of free base porphyrins : understanding the role of macrocyclic distortion

Porphyrins have been the center of numerous investigations in different areas of chemistry, geochemistry, and the life sciences. In nature the conformation of the porphyrin macrocycle varies, depending on the function of its apoenzyme. It is believed that the conformation of the porphyrin ring is necessary for the enzyme to achieve its function and modify its reactivity. It is important to understand how the conformation of the porphyrin ring will influence its properties. In synthetic porphyrins particular conformations and ring deformations can be achieved by peripheral substitution, metallation, core substitution, and core protonation among other alterations of the macrocycle. The macrocyclic distortions will affect the ring current, the ability of pyrroles to intramolecularly hydrogen bond and the relative basicity of each of the porphyrins. To understand these effects different theoretical models are used. The ground state structure of each of 19 free base porphyrins is determined using molecular mechanics (MM+) and semiempirical methods (PM3). The energetics of deformation of the macrocyclic core is calculated by carrying out single point energy calculations for the conformation achieved by each synthetic compound. Enthalpies of solution and enthalpies of protonation of 10 porphyrins with varying degrees of macrocyclic deformation and varying electron withdrawing groups in the periphery are determined using solution calorimetry. Using Hess's Law, the relative basicity of each of the different free base porphyrins is calculated. NMR results are described, including the determination of free energies of activation of ring tautomerization and hydrogen bonding for several compounds. It was found that in the absence of electronic effects, the greater macrocyclic deformation, the greater the basicity of the porphyrins. This basicity is attenuated by the presence of electron withdrawing groups and ability to of the macrocycle to intramolecularly hydrogen bond.

Murray-Darling basin governance : the focus of the law

The legal arrangements for the management of the Murray-Darling Basin in Australia have changed significantly over the years. The Constitution of the Commonwealth has led to the legal arrangements for the management of the Murray-Darling Basin. The Water Act 2000 of Queensland aimed at advancing sustainable management and efficient use of water and other resources by establishing a system for the planning, allocation and use of water. The Water Management Act 2000 of New South Wales ensures the sustainable and integrated management of the water resources of the state benefiting the present and future generations. The Natural Resources Management Act 2004 of South Australia applies to water resources and to other natural resources. The Act aimed at assisting the achievement of ecologically sustainable development in the state.

Deviation from Murray's law is associated with a higher degree of calcification in coronary bifurcations

Murray's law describes the optimal branching anatomy of vascular bifurcations. If Murray's law is obeyed, shear stress is constant over the bifurcation. Associations between Murray's law and intravascular ultrasound (IVUS) assessed plaque composition near coronary bifurcations have not been investigated previously.

A sustainable Murray-Darling Basin : the legal challenges

The range of legal instruments informing how the Murray-Darling Basin (MDB)is managed is extensive. Some provide guidance; a number indicate strategies and policies; some assume the form of protectable rights and enforceable duties.What has emerged is a complicated and sophisticated web of interacting normative arrangements. These include: several international agreements including those concerning wetlands,biodiversity and climate change; the Constitution of the Commonwealth; the Water Act 2007 of the Commonwealth; the Murray-Darling Basin Agreement scheduled to the Act; State water entitlements stated in the Agreement; Commonwealth environmental water holdings under the Act; the Murray-Darling Basin Plan; water-resource plans under the Act or State or Territorial water legislation; State and Territorial water legislation; and water entitlements and water rights under State or Territorial water legislation.

Remixing Canadian copyright law: A review essay on'An Emerging Intellectual Property Paradigm','Canadian Copyright: A Citizen's Guide'; and'RiP!: A Remix Manifesto', Prometheus, Vol. 27 (3), p. 297-305

In her album, Hymns of the 49th Parallel, the chanteuse K.D. Lang pays tribute to a series of great Canadian songwriters—such as Neil Young, Leonard Cohen, Joni Mitchell and Jane Siberry. In a similar spirit of celebration, this review essay pays homage to a number of recent texts and films dealing with Canadian intellectual property. First, it considers Ysolde Gendreau’s collection, An Emerging Intellectual Property Paradigm: Perspectives from Canada. Second, this essay looks at Laura Murray and Samuel Trosow’s manual, Canadian Copyright: A Citizen’s Guide. Finally, this review evaluates Brett Gaylor’s documentary, RiP! A Remix Manifesto. The three works share certain affinities—a spirit of scepticism about the legitimacy and the efficacy of existing networks of law, policy and bureaucracy; a populist interest in the impact of intellectual property on the everyday lives of citizens, creators and consumers; a passion for human rights; and a melioristic desire for sensible law reform of copyright law and related regimes of intellectual property.

By-Law no. 12

A by-law begins: "It was then moved by R.S. Kinner and Seconded by George Barnes that by Law No. 12 be read. Whereas by Identure bearing date thirteenth day of August A.D. 1873 made between one George Barnes of the first part thereof and Andrew S. Kinner and Charles Robert Murray of the second part thereof which said Identure was duly registered in the Registry Office for Lands for the said County of Lincoln on the 14th day of August A.D. 1880 in Book 4 for the Township of Louth as No. 1534 the said George Barnes granted and conveyed the Lands and premises therein described to the said Andrew S. Kinner and Charles Robert Murray and their heirs and assigns as joint tenants and not as tenants as common upon the trusts and for the purposes therein expressed. And Whereas the said Andrew S. Kinner died on about the 13th day of June 1877 A.D. without having made any appointment under the provisions of the said in part recited Identure.."