Disintegration Factor Research Articles

The properties of tablets containing microcrystalline cellulose.

Tablets have been prepared from mixtures of microcrystalline cellulose (Avicel) and spray dried lactose. Tests on these showed that a maximum value of dissolution rate occurred as the percentage of the cellulose increased. This maximum was at 4% w/w for mixtures containing Avicel PH 101 and coincided with the point of maximum liquid penetration rate. With grade PH 105 this maximum was at 2% w/w and corresponded to the optimum balance between the opposing factors of disintegration and liquid penetration rate. Addition of up to 2% w/w magnesium stearate to the formulation containing 4% w/w PH 101 grade had little effect on pore structure, but decreased the dissolution rate by retarding water penetration. Similar concentrations of Carbowax 4000 caused no such decrease.

Modeling and analysis of the edge disintegration in the EDM drilling cobalt-bonded tungsten carbide

The characteristic feature of edge disintegration easily appears in the electric discharge machining (EDM) drilling processing of cobalt-bonded tungsten carbide (WC-Co). Such tendency reduces the strength against fatigue and results in a poor assembly tolerance. The objective of this paper was to present the mathematical models for modeling and analysis of the effects of process parameters, including the discharge current, pulse time on, duty factor, and capacitance value, on the disintegration factor at the entrance edge of drilled hole in the EDM drilling process of cobalt-bonded tungsten carbide. An experimental plan of a central composite design based on the response surface methodology (RSM) was employed to carry out the experimental study. The quadratic model of RSM associated with the sequential approximation optimization method was used to find the optimum settings of processing parameters. With the experimental values up to a 95% confidence interval, it is fairly well for the experimental results to present the mathematical model of disintegration factor. The results show that the interaction effect of discharge current with capacitance value has the greatest influence on the disintegration factor, followed by the capacitance value and the quadratic term of duty factor. The optimal settings of processing parameters obtained in this study represent the reduction of the 5.53% disintegration factor, which were compared with the results of initial processing parameters for drilling the cobalt-bonded tungsten carbide in the EDM process.

Prediction of thermal hydrolysis pretreatment on anaerobic digestion of waste activated sludge

Thermal hydrolysis is known for an efficient sludge disintegration capability to enhance biogas potential--but to which extent? Obviously, residual VSS concentration in digested sludge gives not sufficient information to predict additional biogas potential. In this paper, different types of waste activated sludge (WAS) were pre-hydrolysed by a full-scale Thermo-Pressure-Hydrolysis Process (Thermo-Druck-Hydrolyse, TDH) and break-down mechanisms on specific organic compounds were investigated. The IWA Anaerobic Digestion Model No.1 (ADM1) has been used for a systematic analysis of monitoring data gained from experimental work. The TDH process combined with anaerobic digestion can be well described by a modified ADM1 model that includes an X(P)-fraction (inactivated aerobic biomass and their decay products). More rapid and more complete degradation of TDH-treated sludge is represented by calibrated disintegration rate and disintegration factors, while biokinetic parameters of acetogenesis and methanogenesis show no sensitivity. TDH process impacts mainly biomass and decay products while inerts Xi already contained in the raw wastewater are hardly converted. Final concentration of soluble inerts in digestion effluent has been increased from 2% to 9% of influent COD due to thermal hydrolysis. An increase in biogas generation (ca. +80%) and in ammonia release (ca. +75%) can be explained by complete degradation of cell mass.

Continuous thermal hydrolysis and energy integration in sludge anaerobic digestion plants

A thermal hydrolysis pilot plant with direct steam injection heating was designed and constructed. In a first period the equipment was operated in batch to verify the effect of sludge type, pressure and temperature, residence time and solids concentration. Optimal operation conditions were reached for secondary sludge at 170 degrees C, 7 bar and 30 minutes residence time, obtaining a disintegration factor higher than 10, methane production increase by 50% and easy centrifugation In a second period the pilot plant was operated working with continuous feed, testing the efficiency by using two continuous anaerobic digester operating in the mesophilic and thermophilic range. Working at 12 days residence time, biogas production increases by 40-50%. Integrating the energy transfer it is possible to design a self-sufficient system that takes advantage of this methane increase to produce 40% more electric energy.

Determination of immediate roof at mines of the Kutahya-Omerler coal basin, Turkey

The estimation of the relations between excavation height, longwall advance rate, convergence around a longwall in the roof-soil direction, and load distribution on support is reported, that are of specific importance for selecting support type. The principal attention is focused on determination of the immediate roof height that depends on the mobility characteristics of overlying rocks and governs mainly the stoping convergence and load intensity on the support. Numerical modeling, laboratory and field experiments are undertaken in this study, which included evaluation of composition and physicomechanical properties of rocks, assessment of stress-strain state of rock mass and of the immediate roof height, measurements of disintegration and bulking factor of overlying rocks, convergence of stoping floor and roof, and loads on hydraulic legs of supports. The study parameters obtained by different methods for the Omerler Mine are presented.

Response of Air-Entrained Concrete to Severe Chemical Aggression

The primary objective of this study is to investigate the response of air-entrained concrete to aggressive chemicals. To better correlate to field practices, 60 concrete mixtures were prepared with three cement contents, five air content ranges, and water content adjusted to yield moderate to high slump ranges. Samples were subjected to abrasion testing and were exposed to sulfuric acid, calcium chloride, and ammonium sulfate solutions. The results reveal that air-entrained mixtures yielded reduced permeability but relatively less abrasion resistance. Yet they demonstrated enhanced resistance to chemicals as expressed by more exposure cycles and/or less mass loss. The combined effect of both exposure duration and mass loss is expressed by a factor (chemical disintegration factor), which is thought to be useful in similar studies. The results suggest that producing high workability, air-entrained concrete with adequate strength and abrasion resistance, low permeability, and superior chemical resistance is possible. This can be useful in sewer structures and concrete applications where surfaces are subjected to mild abrasion and aggressive chemicals.

Politico-geographic aspects of regionalization of Serbia

The concept of the regional politico-territorial organization of Serbia is one of the most adequate ways to eliminate internal destructive processes in country. The idea and suggested division in the essay 'The regional country' by M. Jovic need some changes from the aspect of political geography. Suggested corrected regional model should fulfill basic task - to eliminate factors of disintegration. According to this, it contains: more regions, partially changed their names, new borders that annul fragmental and barrier effects of provincial borders, regional functional-gravitational integration, but not introvercy, integration openness of provincial regions towards neighbors (especially other Serbian countries), but not possibility for secession. The principle of physico-geographic complementarity is fulfilled, except its disintegrational politico-territorial influence.

Regional Maritime Regime Building: Prospects in Northeast and Southeast Asia

Maritime issues are rising to the forefront of Asian security concerns. But maritime management regimes can constrain conflict and create confidence in co-operation. Such regimes can define the range of permissible state behavior and resolve dilemmas stemming from the sharing of common resources. Regimes originate through imposition, spontaneous processes, or negotiation and are supplied when there is sufficient demand for the functions they perform. Integrative forces that support regime formation are the existence of other international arrangements in the region; ethnic, cultural, or historical interstate relationships; and clear indications of benefits to be gained. Often a shock or crisis enhances regime formation or its robustness. Disintegrative forces include political or territorial differences, competition for leadership, and opposition to regionalism. In regional co-operation on maritime issues, Southeast Asia is clearly more advanced than Northeast Asia. However, the absence of robust multilateral maritime regimes in Asia reflects state perceptions that the costs outweigh the benefits. The primacy of dis-integrative factors argues strongly for an ad hoc, issue-specific, evolutionary process for multilateral maritime regime building in Asia.

The New Constitutionalism and the Impact of Spill-wer

This article provides a preliminary examination of the political consequences of constitutional reform for the territorial management of the British State. Drawing on European integration theory, it argues that the constitutional reform process can best be examined through the lens of a modified neo ficnctionalist approach which allows the political scientist to: (1) study constitutional reform as a process; (2) describe what appears to be going on in the process; (3) identify factors of integration and disintegration; and, (4), predict future outcomes. It concludes that although the New Constitutionalism is likely to be plagued by factors of disintegration that will undermine territorial management and administration, these will be counterbalanced by factors of integration which will increase the radicalism of reform and the scope and intensity of change.

Sources of settling material: aggregation and zooplankton mediated fluxes in the Gulf of Riga

The composition of sedimenting matter from the upper mixed layer was studied in relation to aggregation dynamics and food web structure in the stratified southern Gulf of Riga, Baltic Sea. Four stations were visited during three fortnight periods in spring (1995), midsummer (1994) and late summer (1993). In spring, diatoms constituted the major part of the sedimenting matter, and their abundance in the water column declined due to the sedimentation loss. A technique which preserves the structure of the sedimenting matter was applied; it revealed that neither diatoms nor other algae were sinking as aggregates. Occasionally both motile phytoplankton and heterotrophic organisms concentrated in the sediment traps, possibly due to vertical migration. In midsummer, and especially late summer, heterotrophic biomass was large relative to autotrophic biomass; however, total heterotrophic biomass had a maximum during midsummer. During the summer periods the sedimenting matter consisted of products from the metazoa (faecal pellets, eggs, cuticles) as well as of amorphous detritus, which mainly sedimented in the form of aggregates. Physical coagulation may have produced these aggregates, but turbulent shear, which was the major force making suspended particles collide, did not correlate with aggregate sedimentation. A disintegration factor related to high turbulence may also be of importance. The sedimentation of faecal particles and other detritus was low compared to the zooplankton biomass (0.6–8% day −1). Despite the eutrophic conditions of the Gulf of Riga there is a high recycling relative to the sedimentation. This may be related to the importance of auto- and heterotrophic picoplankton in the carbon flow, to the generally high heterotrophic biomass and to an efficient detritus decomposition.

Understanding prehistoric images in the post-historic age: A cognitive project

The reappropriation of the past in the post-historic age results in vernacular interpretations . Histor y an d prehistor y ar e continuousl y 'democ ratized', opportunistically reconstituted according to a teleology more of commerce, whic h implie s vulgarization , tha n o f relevan t knowledge . Petroglyphs an d roc k painting s (after , o r alon g with , dinosaurs ) coul d not escape this destiny. Declared early on as works of art, the best known became objects of speculative writing and procession sites. One could not exactly collect them, but i f this had been possible, we would have major collectors inviting us to their caves, and many art dealers authenticating a ne w 'unique' wor k with whic h the owne r has t o par t becaus e of the recession (or whatever other lucrative reason). When some of the procession site s ha d t o b e close d du e t o damag e inflicte d b y indiscriminat e visiting practices, simil i — Lascaux II i s the best known — were built in the environs , and th e lesse r know n site s took thei r place . I t woul d be arrogant an d self-defeating to see in the ever increasing popular interes t in thes e 'messages ' fro m ou r ancestor s onl y th e consume r aspec t (a s strong as this actually is). It might be that Only the wrong people travel', at leas t i f we consider the increasing number of sites vandalized an d th e tour packages offered by the tourist industry. Layers over layers of graffit i complete and cover early images, detracting from the primary significance of such places/But once on record, these added signs become part of the context, testimon y t o somethin g else , bu t nevertheles s testimon y o f a sort. To this 'voluntary contribution' of the new geniuses of graffiti, on e ought t o ad d th e involuntar y contribution o f pollution , a s wel l a s th e action of natural elements (wind, rain, seasonal variations, etc.). In short, what happene d wit h th e origina l expressio n ove r man y thousand s o f years continues to happen , bu t s o much faster, as we make progress in understanding this almost irresistible urge humans have to leave a mark. At times, it seems that a contest is taking place: factors of disintegration vs. the urge to know and preserve. Acknowledging various ways in which petroglyphs are appropriated — by populations stil l connected to them,

Suicide, alcohol, and divorce; aspects of gender and family integration.

Both over time and between countries within our cultural domain there seems to be a persistent male predominance in the suicide rate. Based on Durkheim's theory of social integration as a key issue in egoistic suicide, the present study aimed at analyzing two empirically operational aspects of social disintegrative factors on the male and female suicide rates in Norway; namely alcohol consumption and divorce. Times series analyses on differenced data from 1911 to 1990 showed that both alcohol consumption and divorce were independently and statistically significantly associated with the male suicide rate, but not with the female suicide rate. The results are discussed on basis of gender roles and social integration.

Confessional mentality as a (dis)integration factor

Confessional mentality as a (dis)integration factor

Inflation, Revaluation, and the Crisis of Middle-Class Politics: A Study in the Dissolution of the German Party System, 1923–28

Thedissolution of the German party system during the Weimar Republic was well advanced long before either the world economic crisis descended upon Germany with all of its intensity in the early 1930s or the National Socialists scored their first decisive breakthrough into the ranks of Germany's middle-class parties. While both the onset of the depression and the rise of National Socialism greatly accelerated the dissolution of Germany's bourgeois parties, their principal effect was not so much to catalyze this process as to intensify disintegrative factors that had been present ever since the founding of the Weimar Republic. The ultimate cause of the dissolution of the bourgeois party system during the Weimar Republic lay precisely in the inability of established bourgeois parties such as the German Democratic Party (Deutsche Demokratische Parteior DDP), the German People's Party (Deutsche Volksparteior DVP), the German National People's Party (Deutsdmationale Volksparteior DNVP), and to a somewhat lesser extent the German Center Party (Deutsche Zentrumspartei) to integrate the diverse and increasingly antagonistic social and economic interests which constituted their material base into a viable and effective social force. The emergence of special-interest parties in the second half of the 1920s bore dramatic testimony to the failure of Germany's nonsocialist parties to provide the more traditional elements of the German middle class with the effective political representation they needed in order to maintain their social and economic position in the face of mounting economic adversity. Not only did the formation of such parries reflect the process of social and political decay that was at work within the German party system, but the increasing fragmentation of Germany's established bourgeois parties greatly facilitated the penetration of National Socialism into the ranks of the German middle strata.

Characteristics of the physical state of blasted rock and their relations to the disintegration factor

Characteristics of the physical state of blasted rock and their relations to the disintegration factor