Decomposition of pyrite and trapping of sulphur in a coal matrix during pyrolysis of coal

The thermal decomposition of pyrite crystals in coal from the Prince Colliery, Cape Breton, Nova Scotia, has been studied to determine both the temperature of decomposition and the distribution of the sulphur liberated into the coal matrix. Under the experimental conditions used, pyrite decomposes to pyrrhotite between 500 and 550 °C. For small (20 μm) crystals embedded in the coal matrix, essentially all of the sulphur liberated by the decomposition of FeS₂ becomes trapped in the matrix within a distance of 15 μm.     

Sizing up models of heart failure: Proteomics from flies to humans

Cardiovascular disease is the leading cause of death in the western world. Heart failure is a heterogeneous and complex syndrome, arising from various etiologies, which result in cellular phenotypes that vary from patient to patient. The ability to utilize genetic manipulation and biochemical experimentation in animal models has made them indispensable in the study of this chronic condition. Similarly, proteomics has been helpful for elucidating complicated cellular and molecular phenotypes and has the potential to identify circulating biomarkers and drug targets for therapeutic intervention. In this review, the use of human samples and animal model systems (pig, dog, rat, mouse, zebrafish, and fruit fly) in cardiac research is discussed. Additionally, the protein sequence homology between these species and the extent of conservation at the level of the phospho-proteome in major kinase signaling cascades involved in heart failure are investigated.     

An intelligent ultrasonic inspection system for flooded member detection in offshore structures

An ultrasonic system for automatic underwater inspection of steel jacket offshore installation is described. It is based on the unambiguous detection of water ingress in normally sealed tubular members, thereby providing an indication of through-wall structural failure. A novel transducer design, based on a dual frequency array of 1-3 connectivity thickness drive transducers, is used to provide the required sensitivity and act also as an environmental monitor for input to an expert system, which performs automatic data analysis. Although intended primarily for operation on a remotely operated vehicle, the system may be employed satisfactorily by a driver. A series of test trials is described, and the prototype is shown to perform very well for all intended modes of operation.     

Extended active observer for force estimation and disturbance rejection of robotic manipulators

The current control methods applied to robotic manipulators either require full state and force measurements, or use the state and force estimation in the absence of any kind of disturbance. As an alternative approach, a new adaptive motion control approach for robotic manipulators extending the existing active observer for simultaneous inertial parameters and force estimation is proposed. The scheme provides accurate force and full state estimation in the presence of robot inertial parameter variations and measurement noise, both subsequently used in the design of a controller. Since the proposed method relies mainly on the position of the plant, it significantly reduces the difficulty and cost of implementation. The velocity, parameter and force signals are estimated from the position. The approach is applied to a typical two-degree-of-freedom (2DOF) robotic manipulator through computer simulation. The results are encouraging and demonstrate the noise rejection ability of the scheme.     

二氧化钛的全球供需情况

TZMI最近对二氧化钛的供应和需求的预测都作了重大的修正。以北半球涂料市场的周期变化来看，消费量的季度增长比早先预测的要弱，二氧化钛需求正在减速。大部分主要的国际生产商已公布的2005年上半年销售量与2004年上半年相比均有下降，尽管有些生产商销售了其2004年的多余库存。西欧需求的增长较平缓，而且2005年的需求不大可能萎缩。     

Multicriteria diversity analysis: A novel heuristic framework for appraising energy portfolios

This paper outlines a novel general framework for analysing energy diversity. A critical review of different reasons for policy interest reveals that diversity is more than a supply security strategy. There are particular synergies with strategies for transitions to sustainability. Yet – despite much important work – policy analysis tends to address only a subset of the properties of diversity and remains subject to ambiguity, neglect and special pleading. Developing earlier work, the paper proposes a more comprehensive heuristic framework, accommodating a wide range of different disciplinary and socio-political perspectives. It is argued that the associated multicriteria diversity analysis method provides a more systematic, complete and transparent way to articulate disparate perspectives and approaches and so help to inform more robust and accountable policymaking.     

The influence of additives on the burning of clouds of coal particles in shocked gases

The influence of additions of 1% by volume of methyl chloride, methyl iodide, methanol, acetone, and tetra-methyl and tetra-ethyl lead, on the burning of cloudds of coal particles in shocked oxygen and air has been studied. These additives were chosen on the basis of their marked effect on the burning of homogeneous systems. Their lack of effect in the early stages of burning in the present experiments suggests that the initial phase may be a heterogeneous reaction. Detonations were observed to occur with volumetric concentrations of less than 1% of tetra-ethyl and tetra-methyl lead in the presence and absence of particles of coal. Such concentrations are below the normal lower limit of flammability. This anomaly is explained in terms of a pyrolytic reaction liberating methyl or ethyl radicals prior to ignition and the production of an accelerating flame front.     

Effect of processing technique on the transport and mechanical properties of graphite nanoplatelet/rubbery epoxy composites for thermal interface applications

Graphite nanoplatelet (GNP)/rubbery epoxy composites were fabricated by mechanical mixer (MM) and dual asymmetric centrifuge speed mixer (SM). The properties of the GNP/rubbery epoxy were compared with GNP/glassy epoxy composites. The thermal conductivity of GNP/rubbery epoxy composite (25 wt.% GNP, particle size 15 μm) reached 2.35 W m⁻¹ K⁻¹ compared to 0.1795 W m⁻¹ K⁻¹ for rubbery epoxy. Compared with GNP/rubbery epoxy composite, at 20 wt.%, GNP/glassy epoxy composite has a slightly lower thermal conductivity but an electrical conductivity that is 3 orders of magnitude higher. The viscosity of rubbery epoxy is 4 times lower than that of glassy epoxy and thus allows higher loading. The thermal and electrical conductivities of composites produced by MM are slightly higher than those produced by SM due to greater shearing of GNPs in MM, which results in better dispersed GNPs. Compression and hardness testing showed that GNPs increase the compressive strength of rubbery epoxy ∼2 times without significantly affecting the compressive strain and hardness. The GNP/glassy epoxy composites are 40 times stiffer than the GNP/rubbery epoxy composites. GNP/rubbery epoxy composites with their high thermal conductivity, low electrical conductivity, low viscosity before curing and high conformability are promising thermal interface materials.     

Satisficing Equilibria: A Non-Classical Theory of Games and Decisions

Satisficing, or being good enough, is the fundamental obligation of rational decision makers. We cannot rationally choose an option, even when we do not know of anything better, unless we know it is good enough. Unfortunately, we are not often in the position of knowing that there could be no better option, and hence that the option must be good enough. A complete search through all logical possibilities is often impractical, particularly in multi-agent contexts, due to excessive computational difficulty, modeling complexity, and uncertainty. It can be equally impractical, if it is even possible, to determine the cost of the additional required search to find an option that is good enough. In a departure from the traditional notion of satisficing as a species of bounded rationality, satisficing is here redefined in terms of a notion of intrinsic rationality. Epistemic utility theory serves as the philosophical foundation of a new praxeological decision-making paradigm of satisficing equilibria that is applicable to both single- and multiple-agent scenarios. All interagent relationships are modeled by an interdependence function that explicitly accommodates both self and group interest, from which multilateral and unilateral selectability and rejectability mass functions can be derived and compared via the praxeic likelihood ratio test.     

Satisficing Revisited

Minds and Machines - In the debate between simple inference heuristics and complex decision mechanisms, we take a position squarely in the middle. A decision making process that extends to both...