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The purpose of this paper is to answer why the predominant competitive reaction (CR) is non-reactive one in the previous literature by showing that some fluctuations of CR may average out to zero.

This research proposes a model for measuring CR volatility to examine whether a firm’s CR differs over time. A rolling-windows time series approach is applied to three different data sets.

The results show that firms indeed react to each other, but the types of reactions vary over time, thereby creating a misunderstood “no-reaction” in the literature.

This study may help understand the gap between academic findings (i.e. no-reaction) and managerial reality (i.e. marketing wars).

Although a firm’s CR should be understood as a series of managerial actions that may change over time, the extant literature has not considered this temporal variation of CR. This paper provides a systematic review of the empirically based literature and provides insights into the importance of strategic variation in competitive dynamics.

The purpose of this paper is to apply the numerical methods to study the heap leaching process in a bed of porous and spherical ore particles. This study is performed in two stages: first, modeling the leaching process of a soluble mineral from a spherical and porous ore particle to obtain the distribution of mineral concentrations, leaching solvent concentration and dissolved mineral in the particles (the particle model), and second, modeling the heap leaching of the mineral from a porous bed consisting of spherical and porous ore particles to obtain the distribution of mineral concentrations, leaching solvent concentration and dissolved mineral in the bed (the bed model).

The governing equations are derived for the particle model, and then converted into non‐dimensional form using reference quantities. The non‐dimensional equations are discretised on a uniform spherical grid fitted to the particle using finite difference method. The resulting algebraic equations are solved using Tri‐Diagonal Matrix Algorithm, and the governing equations are derived for the bed model, and then converted into non‐dimensional form using reference quantities. The non‐dimensional equations are discretised explicitly on a one‐dimensional and uniform grid fitted to the bed. The unknown quantities are evaluated using the corresponding values at the previous time interval.

The results obtained from numerical modeling show that, when the particle has a low diffusion resistance or a high chemical resistance, the reaction takes place slowly and homogeneously throughout the ore particle. On the other hand, when the bed has a low convection resistance, the reaction takes place homogeneously throughout the bed. As the convection resistance increases, the non‐homogeneous (local) behavior predominates. It is also noticed that, when the chemical reaction resistance is high, the reaction takes place homogeneously throughout the bed.

The dynamic diffusion and movement of solution in the ore particles and ore bed are not modeled and volumetric ratio of solution in the particles and the bed and also vertical velocity of solution in the bed are assumed to be fixed constants.

This study shows that the reaction takes place homogeneously throughout the bed when the convection resistance is low, the diffusion resistance is high, the concentration resistance is low, and the chemical reaction resistance is high.

Homogeneous reaction conditions being suitable for heap leaching operations are identified. Thus, it is recommended to approach the above conditions when preparing ore heaps and designing the relevant operation.

The paper's aim is to suggest a new micro‐thermonuclear reactor for aerospace.

Methods of the thermonuclear physics are used for the research.

The result is new micro‐thermonuclear reactor with very small fuel pellet that uses plasma confinement generated by multi‐reflection of laser beam or its own magnetic field. The Lawson criterion increases by hundreds of times. The author also suggests a new method of heating the power‐making fuel pellet by outer electric current as well as new direct method of transformation of ion kinetic energy into harvestable electricity. These offered innovations dramatically decrease the size, weight and cost of thermonuclear reactor, installation, propulsion system and electric generator.

The author is researching the efficiency of these innovations for two types of the micro‐thermonuclear reactors: multi‐reflection reactor (inertial confinement fusion) and self‐magnetic reactor (magnetic confinement fusion).

The author offers several innovations. Results may be used for the design of thermonuclear aerospace engines, propulsion and electric generators.

The purpose of the present study is first to develop a hydroxyl-functionalized ketonic resin for coating applications and to establish a standard characterization protocol; second, to quantify the effects of various operating parameters on resin properties and to develop mathematical models to predict the product properties; and third, to carry out the compatibility study between the in-house developed resins and commercially available resins.

Self-polymerization reactions were conducted in a batch reactor. Effects of reaction time, temperature, catalyst concentration and reactor pressure on product properties have been studied. Hydroxyl value, iodine value, solubility, rheology, gel permeation chromatography (GPC), thermogravimetric analysis (TGA), scanning electron microscope (SEM) and the X-ray diffraction (XRD) analysis were carried out to characterize the product properties. Mark–Houwink correlation was used to predict molecular weight of the resins.

The study shows that hydroxyl value and softening temperature (ST) of the product increased with the increase of reaction temperature, duration of reaction and alkali concentration. However, the solubility value of the resins decreased with the increase of temperature, time and alkali concentration. Regression models were developed to predict the optimum conditions for obtaining a desired quality of resin. The number-average molecular weight of the developed resins was in the range of 450-1150. The products are thermally stable up to around 200°C, and adequately soluble in many commercial solvents.

The ketonic resin can be used as a substitute of phenolic resins which are prepared from more hazardous materials monomers such as phenolic and aldehyde compounds.

The resin can be used as a substitute of more hazardous materials such as phenolic and aldehyde compounds.

This paper details the synthesis of ketonic resin from cyclohexanone and its compatibility. It also investigates the optimization of operating parameters to obtain a desire product.

The purpose of this paper is to present the temporal reflection of electromagnetic waves (EMWs) in simple polar-molecule reactions whose polarization changes with the proceeding of the reactions.

At a temporal boundary, based on the continuity of the electric displacement and magnetic induction, the reflected condition of EMWs is obtained, and the expression of the transmission and reflection coefficients in the reactions is derived. Subsequently, a one-dimensional model is used to validate the reflected condition and expression.

If the time scale of the component concentration variation is greater than the wave period, the polarization of the reactions at a temporal boundary is continuous. The reflection does not happen. On the other hand, when the time scale of the component concentration variation is smaller than the wave period, the polarization is not continuous at a temporal boundary. The impedance of the reactions at the temporal boundary changes and the reflection occurs.

The results may be helpful in disclosing the non-uniform distribution of EMWs in chemical reactions.

The purpose of this paper is to synthesise a novel wet-rubbing fastness improver with diphenylmethane diisocyanate (MDI), polyethylene glycol (PEG), dimethylol propionic acid (DMPA), diethylenetriamine and epichlorohydrin.

The synthetic reaction was carried out through three steps: pre-polymerising, chain-extending and chemically modifying. The influence of monomers dosage and ratio, temperature and time on reaction system and wet-rubbing fastness of reactive dye is studied. The target product was characterised by transform infrared spectroscopy analysis.

The optimum synthetic process condition of the improver is as follows: reaction temperature 100°C; pre-polymering time 2.5 hours with R value [n(NCO): n(OH)] 1.35 and DMPA 7 per cent (on percentage of total moles of MDI and PEG); chain-extending time 30 minutes with diethylenetriamine 1.5 per cent (on percentage of total moles of MDI and PEG); modifying time 2 hours with diethylenetriamine : epichlorohydrin = 1:2 (mole ratio).

The synthetic product is a three-functions-in-one (filming, salt-forming and cross-linking) wet-rubbing fastness improver which can obviously improve the wet-rubbing fastness of reactive dyes from Grade 2-3 to Grade 4.

The wet-rubbing fastness improver is novel and could find numerous applications in dyeing and finishing.

The purpose of this paper is to prepare a higher chloromethylation degree (CD) modified macroporous adsorption resin (MAR, LX1180-Cl) and further study their adsorption performance.

CD and crosslinking degree were evaluated using stationary potential step and rotating-disk method, the adsorption performance of LX1180-Cl and LX1180 for flavonoids were studied using the UV-VIS spectrophotometry.

This research realized high CD (9.6 mass %) on high crosslinking MAR, LX1180. In tandem, the adsorption performance of them to flavonoids finds that the matching degree of polarity (presented with CD) and size were the critical factor to adsorption. It was also found that the reaction time had reduced to 24 h with the addition of iron particles into the zinc chloride (ZnCl₂) catalyst.

The study on reaction mechanism and the function principle of hybrid catalyst were speculated, but not the rigid experimental result.

This contribution can provide a rule for the separation and purification of natural products with the aim to improve food additive removal or isolation and purification of flavonoids used for healthcare applications.

This contribution provided a novel way to obtain high degree of CD with high crosslinking MAR, CD of commercially available MAR was improved by 2.5 times to 9.6 percent under crosslinking degree at 58.2 percent, compared with reported CD value (ca. 4.2 percent under crosslinking degree at 20.0 percent), which will be useful in the following further systematically research about the adsorption and separation selectivity of MAR. Besides, the primitive chosen principle of MAR according to the substrate was also presented. Moreover, the chloromethylation mechanism, although speculative, was briefly presented, which will stimulate the related study.

Non‐linear reaction‐diffusion processes with cross‐diffusion in two‐dimensional, anisotropic media are analyzed by means of an implicit, iterative, time‐linearized approximate factorization technique as functions of the anisotropy of the heat and species diffusivity tensors, the Soret and Dufour cross‐diffusion effects, and five types of boundary conditions. It is shown that anisotropy and cross‐diffusion deform the reaction front and affect the front velocity, and the magnitude of these effects increases as the magnitude of the off‐diagonal components of the heat and species diffusivity tensors is increased. It is also shown that the five types of boundary conditions employed in this study produce similar results except when there is either strong anisotropy in the species or heat diffusivity tensors and there are no Soret and Dufour effects, or the species and heat diffusivity tensors are isotropic, but the anisotropy of the Soret and Dufour effects is important. If the species and heat diffusivity tensors are isotropic, the effects of either the Soret or the Dufour cross‐diffusion effects are small for the cases considered in this study. The time required to achieve steady state depends on the anisotropy of the heat and diffusivity tensors, the cross‐diffusion effects, and the boundary conditions.