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The combination of large eddy simulation (LES) and newly proposed Taylor-series expansion method of moments (TEMOM) is performed for simulating particulate matters emitted from vehicle engine tailpipe. The momentum, heat and mass transfer, binary homogeneous nucleation, Brownian coagulation, Brownian and turbulent diffusion, condensation and thermophoresis are simultaneously taken into account. Good agreements between the experimental and simulated results with respect to the pollutant dispersion are obtained. Compared to other published methods, the present TEMOM requires the least computational time with much accuracy for predicting nanoparticle dynamics. The instantaneous results show that large eddies dominate the evolution of particulate dynamics as exhaust develops, while binary homogeneous sulfuric-water nucleation mainly appears at the interface between the exhaust and ambient cool gases. The increasing of fuel sulfur content and relative humidity or the decreasing of environment temperature leads to an increase in particulate product rate, while volume-averaged particle diameter increases with increasing fuel sulfur content and environment temperature. The variation of geometric standard deviation suggests the nucleated particles eventually approach the asymptotic distribution in the dilution atmosphere, and this distribution is independent of the fuel sulfur content. The variance of upstream turbulence intensity significantly affects the evolution of particulate matters inside the plume.

We consider the connection between two mean-field models describing the binary coagulation of discrete clusters moving by spatial diffusion. Both models are generalizations of Smoluchowski's infinite system of coagulation equations. In the first (local) model, the coagulation rates are proportional to the concentrations of the interacting clusters as a consequence of the assumption that two clusters coalesce only if they meet at the same point. In the second (nonlocal) one, the coagulation rates contain integral terms which reflect the nonlocal character of interactions between clusters, the intensity of clusters' encounters depending on the distance between them and being measured by means of some positive parameter ε. It is proved that weak solutions to the nonlocal discrete diffusive coagulation equations converge to that of the local one as ε → 0.

Coal-measure kaolinite is a main gangue mineral in coal deposits. Because of the colloidal particle size, the kaolinite is very stable in coal tailing slurries, leading to a high turbidity of recycled water in coal washing plants. The coagulation of colloidal kaolinite in aqueous suspensions is an essential problem in many coal washing plants. This review highlights the characterizations and stability of colloidal coal-measure kaolinite in aqueous suspensions. The characterizations include mineralogy, electrokinetics and hydration layers on kaolinite surfaces. The coagulation of colloidal kaolinite in aqueous suspensions is reviewed and discussed on the basis of the DLVO theory and the characterization. In addition,the main parameters of affecting the coagulation, such as suspension pH, electrolytic ions and temperature, are summarized.

The process of human blood clotting involves a complex interaction of continuous-time/continuous-state processes and discrete-event/discrete-state phenomena, where the former comprise the various chemical rate equations and the latter comprise both threshold-limited behaviors and binary states (presence/absence of a chemical). Whereas previous blood-clotting models used only continuous dynamics and perforce addressed only portions of the coagulation cascade, we capture both continuous and discrete aspects by modeling it as a hybrid dynamical system. The model was implemented as a hybrid Petri net, a graphical modeling language that extends ordinary Petri nets to cover continuous quantities and continuous-time flows. The primary focus is simulation: (1) fidelity to the clinical data in terms of clotting-factor concentrations and elapsed time; (2) reproduction of known clotting pathologies; and (3) fine-grained predictions which may be used to refine clinical understanding of blood clotting. Next we examine sensitivity to rate-constant perturbation. Finally, we propose a method for titrating between reliance on the model and on prior clinical knowledge. For simplicity, we confine these last two analyses to a critical purely-continuous subsystem of the model.

This paper deals with the convergence of finite volume scheme (FVS) for solving coagulation and multiple fragmentation equations having locally bounded coagulation kernel but singularity near the origin due to fragmentation rates. Thanks to the Dunford–Pettis and De La Vall$é$e-Poussin theorems, we establish that numerical solution is converging to the weak solution of the continuous model using a weak $L^1$ compactness argument. A suitable stable condition on time step is taken to achieve the result. Furthermore, when kernels are in $W_{\mathrm{\text{loc}}}^{1,\infty }$ space, first-order error approximation is demonstrated for a uniform mesh. It is numerically validated by taking four test problems of coupled coagulation–fragmentation models.

Integral collision kernel is elucidated using experimental results for titania, silica and alumina nanoparticles synthesized by FCVD process, and titania submicron particles synthesized in a tube furnace reactor. The integral collision kernel was obtained from a particle number balance equation by the integration of collision rates from the kinetic theory of dilute gases for the free-molecule regime, from the Smoluchowski theory for the continuum regime, and by a semi-empirical interpolation for the transition regime between the two limiting regimes. Comparisons have been made on particle size and the integral collision kernel, showing that the predicted integral collision kernel agreed well with the experimental results in Knudsen number range from about 1.5 to 20.

Reference interval (RIs) were critical to the identification of illness. However, RIs set in one laboratory may not be appropriate for another because of biological, geographical and instrumental factors. Interpretation of clinical data using inappropriate RIs may cause misclassification of results and misdiagnosis that lead to improper treatment. RIs in Taiwan have been mostly referencing from foreign resources, it is desirable to establish one that is closer to the overall conditions in Taiwan (such as breed, climate, diseases, etc.) and to investigate its differences to foreign RIs. The present study used the American Society for Veterinary Clinical Pathology (ASVCP) guidelines to establish in-house RIs for hematological, biochemical and coagulation parameters using dogs in middle Taiwan. The results were also compared to two foreign and one local RIs. The results suggested that the hematological RIs are more comparable to foreign RIs than the biochemical and hemostatic parameters. Differences were found for biochemical parameters including gamma-glutamyl transferase (GGT), lactate dehydrogenase (LDH), lipase, uric acid, bile acid, bilirubin and magnesium; and coagulation parameters including prothrombin time (PT) and activated partial thromboplastin. In all, 18% (7/40) of the all tested parameters were different from the local RI while 38% (18/48) and 41% (19/46) of the parameters were different from the two foreign RIs. The differences in more than 30% RIs and better similarities to local RIs underscore the importance of having own RIs if possible.

Site-specific single polyaniline nanowires were fabricated through electrophoresis growth with acetone wetting. After growing the nanowires, the post-process of acetone wetting of the nanowires improved morphology, topology, and electrical conductivity with coagulation and substitution in polyaniline. They showed resistance changes of 39.57 ± 11.57% and presented 2.38 × 10^-4 ± 3 × 10^-5 Ω · cm, 133.77 ± 13.82 nm thickness, and 133.17 ± 13.01 nm width in 1 μm to 5.5 μm length. The new combined growth process of electrophoresis and acetone wetting significantly improved reproducibility, reliability, and controllability in the fabrication of single polymer nanowires.

Soot formation and oxidation will be analysed with respect to the most important processes, namely particle inception, coagulation and surface growth. Time-scales of surface growth are estimated for premixed and diffusion flames and compared with time-scales for coagulation. It turns out that characteristic time-scales for soot formation and coagulation are similar and about one order of magnitude larger than the characteristic time-scales for combustion reactions and much smaller than the time-scales of molecular transport.

Coagulation processes will be discussed in detail and a detailed chemistry approach for surface growth will be presented. The detailed information will be put into a soot model that reproduces a number of phenomena in sooting premixed hydrocarbon flames, for example:

(i) the dependence of surface growth and oxidation rates on the chemical ‘environment’ of soot particles; and

(ii) the fraction of soot formed by particle inception and surface growth reactions and addition of polyacrylic aromatic hydrocarbon (PAH).

The ‘fine structure’ of soot is not resolved by this approach, and, furthermore, the predictions depend sensitively on information about the kinetics of growth of PAH-like structures, the detailed processes occurring on the surface of soot particles, and, most importantly, the pressure dependence of all these processes.

It is well known that solutions of the coagulation equation do not conserve mass if the coagulation kernel grows too rapidly. The phenomenon whereby conservation of mass breaks down in finite time is known as gelation and is physically interpreted as being caused by the appearance of an infinite "gel" or "superparticle." In this paper we discuss the post-gelation behaviour of the coagulation equation with product kernel. Several exact formulas for post gelation mass are given.

In view of the problem that waste acidizing fluid composition is complicated and its dealing is difficult, “Neutralization-Oxidation-Coagulation-Filtration” processing technique has been proposed by regulating the pH value during the process and the removal of total iron, suspended matter and other contaminants on the basis of analyzing the main pollution components of waste acidizing fluid. The objective of this work is to investigate the effects of process conditions on the removal of pollutants, such as chemicals type, chemicals dosage and the processing time, and the process parameters were optimized as follows: the mass ratio of NaOH and CaO was 3:1, c(H₂O₂)=4000mg/L, oxidation time was 20min, c(PAC)=800mg/L, c(PAM)=10mg/L. The results showed that the waste acidizing fluid in oilfield under such treatment could meet the standards of reinjection (SS<10mg/L, oil content<30mg/L, pH=6∼9, corrosion rate<0.076 mm·a⁻¹). Furthermore, this paper provided basis of theoretical and guidance for the reinjection requirements, experiment basis for design and implementation of disposing of wasted acidizing fluid treatment devices.

In this paper, pre-coagulation + low pressure membrane was applied to treat high fluoride water in the laboratory. The removal effect was compared between coagulation, microfiltration and ultrafiltration under certain conditions. Ultra-filtration membranes with pretreatment of coagulation process can achieve a satisfactory effect of fluoride removal. The result of selection and comparison of pretreatment show that PAC is superior to iron salts, and 2 minutes is the optimum time for coagulation. The pH value was adjusted to improve removal effect for membrane separation process.

A combined process of thermolysis and coagulation-flocculation was carried out to treat textile industry wastewater. For the coagulation-flocculation process, the use of magnesium chloride (MgCl₂) and magnesium chloride-polyethylene oxide (MgCl₂-PEO) hybrid polymer as coagulants were compared. The effects of pH and coagulant dosage were varied to obtain optimum colour removal and COD reduction. By using thermolysis alone, 63.1% colour removal and 52.15% COD reduction was achieved. After thermolysis, the wastewater was subjected to coagulation-flocculation using two different coagulants. For both MgCl₂ and MgCl₂-PEO hybrid polymer, the optimum pH for the process was pH 7. When the MgCl₂ coagulant was used, the optimum colour removal and COD reduction obtained were 98.59% and 90.32%, respectively. At pH 7, 99.15% colour removal and 91.94% COD reduction were achieved with the use of the hybrid polymer. The use of the MgCl₂-PEO hybrid polymer does not only show better efficiency in colour removal and COD reduction but also requires a lower coagulant dosage. The optimum efficiency of MgCl₂-PEO hybrid polymer was obtained at 1000 mg/L while for MgCl₂; the optimum coagulant dosage was 1500 mg/L.

The UASB-CASS-coagulation process was used to treat cassava starch wastewater. The application results show that when the COD, BOD₅ and SS of influent were 13078 mg/L, 7297 mg/L and 3386mg/L respectively, the effluent were 96 mg/L, 18mg/L and 42mg/L. The removal rate of three indicators were above 99%. The effluent COD, BOD₅ and SS concentration were stable and met the national standard GB8978-1996 for discharge. At the same time, the gas which made during the wastewater treatment was used to the combustion, getting good environmental and economic benefits.

The starch wastewater has the characteristics of high concentration of COD and BOD, and good biodegradability, the UASB-CASS-Coagulation is used to the treatment of starch wastewater. The effluent treated from the system met the national standard GB8978-1996 for discharge. The application results show that the UASB-CASS-Coagulation combined process has advantages of high stability and efficiency, low running expense, utilizing the available resources, etc.