Carnallite Decomposition into Magnesia,Hydrochloric Acid and Potassium Chloride: II. The Phase Diagram KCl–MgO

Differential thermal analysis and X-ray diffraction of 12 different compositions in the phase diagram KCl–MgO disclose that there exists an area of solid solution, extending from ca. 30–80 equiv. % of MgO/2 (10–55 wf. % MgO), and, depending on the composition, from ca. 759°–775°. Besides the solid solution solid MgO occurs in this area. No chemical reaction between the components takes place.     

Chemically-defined medium for growth and differentiation of mixed epithelial and connective tissues in organ culture

The effect on tissue differentiation and growth in vitro of certain of the factors implicated in collagen synthesis (ascorbic acid, alpha-ketoglutarate and oxygen) and the influence of hydrocortisone was studied using organ cultures of fetal mouse mandible as a mixed epithelial and connective tissue system. Using serum-free Waymouth's MB 752/1 chemically-defined medium, addition of high levels of ascorbic acid (300mug per ml), hydrocortisone (1mug per ml) and oxygen (95%) enhanced differentiation in a number of tissues, in particular skin and appendages, tooth germs and bone, while osteoid and dentine production were noticeable promoted. It is suggested that an essential aspect of media design for organ culture involves the incorporaation of collagen-promoting factors to the in vitro enviornment particularly with regard to the controlling role implicated for collagen in a variety of biological processess.     

AC Corona Charging of Particles

Measurements of the mobility statistics of dioctyl-phthalate (DOP) particles leaving an ac corona charger with various electrode configurations are reported. Mobilities are determined using a laser-Doppler velocimeter (LDV) to measure particle migration velocities in response to a transverse electric field imposed downstream of the charger. Charging models, which do not include effects of finite ion transit times, nonuniform fields, or differences between the distributions of positive and negative wire coronas, predict some of the mobility statistics, especially below 100 Hz, but cannot explain the high-frequency charging. In the turbulent flow with significant corona wind effects the disparate corona current distributions are shown to have a significant effect on the ac corona charging processes.     

Segregation and mixing of fine particles in an ordered mixture

The vertical segregation pattern of an ordered mixture was investigated under various conditions: mixture concentrations, energy input and bed heights. A critical assessment of the application of ‘classical’ segregation mechanisms and an elaboration of the concepts of ‘ordered unit segregation’ and ‘constituent segregation’ are made. A mechanism is proposed for the observed segregation based on the microfluidisation of the frictionally dislodged microfine particles from its carrier and its agglomerates. Mixing mechanism and the effect of fines on the mixing of an ordered mixture were also investigated and mechanisms were proposed.     

On propelling a rod to a maximum vertical or horizontal distance

In order to clarify the problems associated with the application of optimal control theory to the control of animal and human movement, the much simpler but related problems of causing a rod to execute a maximal vertical or horizontal jump are solved via elementary methods. The solutions, which are given in feedback form, are nearly identical even though the performance criteria are quite different. For certain initial conditions an optimal trajectory exists along which the gradient of the optimal performance with respect to the state is discontinuous. A technique to find these trajectories is given. The extension of these results to more realistic models of humans, animals, or walking machines is described.     

Verschleißverhalten von vergütbaren Gesenkstählen

Bedeutung der ?Wirktemperatur? für das Verschleißverhalten von Gesenkstählen. Untersuchungsergebnisse über den Einfluß von Gesenktemperatur, Zugfestigkeit und Legierungsgehalt der Gesenkstähle. Beschreibung eines neu entwickelten Verfahrens (?Stiftverfahren?) zur gleichzeitigen Prüfung mehrerer Gesenkwerkstoffe. Berechnung von Legierungskennzahlen zur Bestimmung des Verschleißverhaltens von chrom-wolfram-molybdän-vanadin-legierten Gesenkstählen.     

Gwinnett County: Changing its service delivery in response to population growth.

Describes the development of a comprehensive management system in the Gwinnett County (Georgia) psychological services unit. The unit altered its service delivery model from one with a primary emphasis on psychoeducational assessment to one focusing on consultation and preventative services. Adherence to the American Psychological Association's specialty guidelines for provision of psychological services in schools is described. This management system enabled the unit to provide quality services to a maximal number of students, parents, and educators, despite the inevitable constraints placed on delivery of services by their growing population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Measurement of trabecular bone thickness in the limited resolution regime of in vivo MRI by fuzzy distance transform

Trabecular or cancellous bone, the type of bone found in the vertebrae and near the joints of long bones, consists of a network of plates and struts. Accurate measurement of trabecular thickness is of significant interest, for example, to assess the effectiveness of anabolic (bone forming) agents of patients with osteoporosis. Here, we introduce a new fuzzy distance transform (FDT)-based thickness computation method that obviates binary segmentation and that can effectively deal with images acquired at a voxel size comparable to the typical trabecular bone thickness. The method's robustness is shown on the basis of micro-CT images of human trabecular bone, resampled at progressively coarser resolution and after application of rotation and addition of noise as a means to simulate the in vivo situation. Reproducibility of the method is demonstrated with micro-CT images by comparing histograms of thickness within and between data sets and with micro-MRI volume data sets of human volunteers imaged repeatedly. Finally, with in vivo micro-MR images from a prior study in rabbits subjected to corticosteroid exposure, it is demonstrated that short-term treatment resulting in trabecular thinning can be quantified with the new method.     

Evaluation of a decision support system for the useful application of hazardous wastes with means of immobilisation-techniques

In the Netherlands, dumping of hazardous wastes on a landfill is discouraged. On the other hand, the Building Material Decree set standards to building materials in order to protect surface-, groundwater and soil from the leaching of hazardous components. Moreover, the government intends to minimise the use of primary materials. Therefore, new applications of hazardous wastes are needed. The most promising is Stabilisation/Solidification, sometimes called immobilisation.Immobilisation-techniques are defined as changing the physical and chemical state of hazardous wastes in order to reduce the leaching of hazardous components. Despite financial incentives, few applications of immobilised wastes are known. Therefore, a Decision Support System (DSS) is necessary to calculate the impact of the immobilised waste on the environment. A DSS is developed and evaluated for a case with contaminated soil and residues from inorganic industry.The first criterion of the DSS is calledlong term behaviour and aims at minimising the release of hazardous compounds in relation to external influences and material properties. The second criterion,environmental load focuses at consumption of (non)renewable natural resources. The third criterion isfinancial consequences, which calculates the overall costs and incomes during the life cycle with respect to all stakeholders.     

Two-stage approach for machine-part grouping and cell layout problems

Cellular manufacturing system (CMS) which is based on the concept of group technology (GT) has been recognized as an efficient and effective way to improve the productivity in a factory. In recent years, there have been continuous research efforts to study different facet of CMS. Most of them concentrated on distinguishing the part families and machine cells either simultaneously or individually with the objective of minimizing intercellular and intracellular part movements. This is known as machine-part grouping problem (MPGP) which is a crucial process while designing CMS. Nevertheless, in reality some components may not be finished within only one cell, they have to travel to another cell(s) for further operation(s). Under this circumstance, intercellular part movement will occur. Different order/sequence of machine cells allocation may result in different total intercellular movement distance unit. It should be noted that if the production volume of each part is very large, then the total number of intercellular movement will be further larger. Therefore, the sequence of machine cells is particularly important in this aspect. With this consideration, the main aim of this work is to propose two-stage approach for solving cell formation problem as well as cell layout problem. The first stage is to identify machine cells and part families, which is the essential part of MPGP. The work in second stage is to carry out a macro-approach to study the cell formation problem with consideration of machining sequence. The impact of the sequencing for allocating the machine cells on minimizing intercellular movement distance unit will be investigated in this stage. The problem scope, which is a MPGP together with the background of cell layout problem (CLP), has been identified. Two mathematical models are formulated for MPGP and CLP respectively. The primary assumption of CLP is that it is a linear layout. The CLP is considered as a quadratic assignment problem (QAP). As MPGP and QAP are NP-hard, genetic algorithm (GA) is employed as solving algorithm. GA is a popular heuristic search technique and has proved superior performance on complex optimization problem. In addition, an industrial case study of a steel member production company has been employed to evaluate the proposed MPGP and CLP models, and the computational results are presented.