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Hydroxypropyl methylcellulose (HPMC) is one of the most important hydrophilic ingredients used in hydrogel matrices preparation (tablets or granules). In this work, HPMC was used to produce granules loaded with hydrophilic and hydrophobic active molecules to investigate their possible use as release dosage forms for pharmaceutical and nutraceutical applications. Unloaded and vitamins loaded HPMC granules were produced by wet granulation to investigate the effect of molecule solubility and granulation liquid type, on physical, mechanical and release properties. Water-soluble vitamin B12 and water-insoluble vitamin D2 were used as model molecules. Due to their different solubility, two granulation liquid phases were also used: distilled water for granules with B12, and ethanol-water for granules with D2. Results showed that use of ethanol in the liquid phase reduces the granulation yield and produces granules having a less defined shape, a smaller mean size, a less hard structure and a worse flowability. Moreover, ethanol slightly enhances the polymer erosion rate. Results also emphasized that the vitamins solubility does not affect either the physical and the mechanical properties of the produced granules. However, it plays a significant relevant role on the molecule release mechanism, being B12 and D2 were released by diffusion and erosion mechanism, respectively.

It is well known that wastewaters from the food industry are a potential source of valuable compounds, such that these wastewaters may be considered by-products awaiting the development of appropriate treatment methodologies. Whey is one of the most important polluting effluents from the milk industry because of its very high biological oxygen demand (BOD). Nevertheless, whey is rich in by-products such as whey proteins and lactose, both of which are widely used industrially. Integrated processes could permit the selective recovery of these by-products in conjunction with the generation of clean, reusable water, thus reducing the environmental impact of this wastewater. Ultrafiltration is a crucial step in the separation and recovery of whey protein and lactose, but this technology suffers from fouling problems that can reduce its performance. New technologies assisted by smart modeling and control systems could improve this ultrafiltration step. In this work, a novel system that allows the recovery of the whey protein in milk industry effluent and the disposal of wastewater was developed and tested. This system utilizes an ultrafiltration process, as this permits the purification of the effluent at room temperature, ensuring the preservation of the recovered proteins. A specially designed autoadaptive fuzzy logic controller evaluates the level of filter membrane fouling and controls a mechanical device that induces filter regeneration. Experimental testing showed that this approach permits process intensification.

Due to its versatile properties, hydroxypropyl methylcellulose (HPMC) is largely used in many applications and deeply studied in the various fields such as pharmaceuticals, biomaterials, agriculture, food, water purification. In this work, vitamin B12 loaded HPMC granules were produced to investigate their potential application as nutraceutical products. To this aim the impact of vitamin load on physico-chemical, mechanical and release properties of granules, achieved by wet granulation process, was investigated. In particular, three different loads of B12 (1%, 2.3% and 5% w/w) were assayed. Unloaded granules (used as control) and loaded granules were dried, sieved, and then the suitable fraction for practical uses, 0.45–2 mm in size, was fully characterized. Results showed that the vitamin incorporation of 5% reduced the granulation performance in the range size of 0.45–2 mm and led granules with higher porosity, more rigid and less elastic structures compared to unloaded granules and those loaded at 1% and 2.3% of B12. Vitamin release kinetics of fresh and aged granules were roughly found the same trends for all the prepared lots; however, the vitamin B12 was released more slowly when added with a load at 1% w/w, suggesting a better incorporation.

The main goal of the pharmacokinetic modeling is the prediction of the drug concentration in the blood, tissues, and organs. The approaches to the modeling of physiological phenomena can be different on the basis of the details used to describe the Adsorption, Distribution, Metabolism, and Excretion (ADME) phenomena. This review is focused on the state of the art in the pharmacokinetic modeling, on the different approaches used to describe the drug fate once it is administered. In particular, the early and the recent developments in the pharmacokinetic and in the gastrointestinal behavior modeling are discussed, together with some case histories of their applications.

There are a few optimal eighth order methods in literature for computing multiple zeros of a nonlinear function. Therefore, in this work our main focus is on developing a new family of optimal eighth order iterative methods for multiple zeros. The applicability of proposed methods is demonstrated on some real life and academic problems that illustrate the efficient convergence behavior. It is shown that the newly developed schemes are able to compete with other methods in terms of numerical error, convergence and computational time. Stability is also demonstrated by means of a pictorial tool, namely, basins of attraction that have the fractal-like shapes along the borders through which basins are symmetric.

In recent years, driving simulators have been widely used by automotive manufacturers and researchers in human-in-the-loop experiments, because they can reduce time and prototyping costs, and provide unlimited parametrization, more safety, and higher repeatability. Simulators play an important role in studies about driver behavior in operating conditions or with unstable vehicles. The aim of the research is to study the effects that the force feedback (f.f.b.), provided to steering wheel by a lane-keeping-assist (LKA) system, has on a driver&rsquo, s response in simulators. The steering&rsquo, s force feedback system is tested by reproducing the conditions of criticality of the LKA system in order to minimize the distance required to recover the driving stability as a function of set f.f.b. intensity and speed. The results, obtained in three specific criticality conditions, show that the behaviour of the LKA system, reproduced in the simulator, is not immediately understood by the driver and, sometimes, it is in opposition with the interventions performed by the driver to ensure driving safety. The results also compare the performance of the subjects, either overall and classified into subgroups, with reference to the perception of the LKA system, evaluated by means of a questionnaire. The proposed experimental methodology is to be regarded as a contribution for the integration of acceptance tests in the evaluation of automation systems.

This study is focused on the characterization of the thermal behavior and physical properties of the most consumed legumes in the daily diet such as beans, lentils and chickpeas. Because of a lack of information in the literature about the effect of microwave treatments on legumes, characterization protocols have been applied before and after subjecting them to microwave irradiation suitable for pest disinfestation. The effects of two different radiative treatments, one suitable for inactivating the infesting fauna and the other simulating uncontrolled treatments, characterized by very high temperatures, were tested. The impacts of microwave treatments on legumes, in terms of thermal behavior, germination capability, tannin and total polyphenol composition and other physical properties (water uptake capability, texture change, mineral losses), after typical soaking cooking processes, are also studied. The thermal properties of the examined legumes were found to be comparable for all samples. Similarly, no significant differences in antinutritional factors, polyphenol and tannin content among all samples were detected. From the structural point of view, samples exposed to high temperatures showed texture degradation and in turn, loss of mineral nutrients during soaking processes. Moreover, their germination capability was drastically reduced. These latter results highlighted why it is important to correctly perform the radiative microwave process in order to both ensure effective and safe disinfestation and avoid nutritional value loss and the worsening of physical properties.

Wet granulation is a size-enlargement process applied in many industrial fields, such as pharmaceutical, nutraceutical, zootecnichal, to improve flowability and compressibility properties of powders. In this work analysis of the particle size distribution (PSD) of granules was performed to understand the phenomena involved during the granulation process and to optimize the operating conditions. Hydroxypropyl methylcellulose (HPMC) granules were produced spraying distilled water as liquid binder on powders in a low-shear granulator. The experimental campaign was planned using the full factorial design statistical technique varying two factors (impeller rotation speed and binder flow rate), each at three intensities. PSDs of HPMC granules at different granulation times were obtained by an ad hoc dynamic image analysis device based on the free falling particle scheme. PSD measurements showed that wet granules size depends on the simultaneous presence of nucleation, agglomeration and breakage phenomena. The process parameters optimization was carried out using response surface methodology (RSM) and using the granulation yield (% w/w of wet granules within the size range 2000–10,000 μm) as the main variable of interest.

Encapsulation may protect unstable, fat soluble vitamins such as vitamin D2 (ergocalciferol). However, encapsulation by the solvent extraction and/or evaporation techniques can require toxic organic solvents, which greatly increase processing costs. The objective of this study was to evaluate the effect on ergocalciferol encapsulation by a combination of the ionic gelation method with the ultrasonic atomization and microwave drying. Optimization of manufacturing parameters included the addition of pluronic-F127 to the core solution at 1.5% w/w to increase the encapsulation efficiency to nearly 92%, greatly improving performance compared to Tween 80 at 0.5% w/w. Microwave treatment at 230 W promoted the recovery of 100% of the ergocalciferol and reduced drying times to about 30 min, while 690 W degraded 40% of the D2. In contrast, the conventional heating degraded 17% of the ergocalciferol during 12 h of processing. By all the applied methods, microparticles were produced with similar gastoresistance properties of less than 10% release at pH of 1.0, to nearly 100% release at pH of 6.8 and 240 min of dissolution. Analysis showed limited ergocalciferol degradation after 5 months of storage.

The full success of pharmacological therapies is strongly depending on the use of suitable, efficient and smart drug delivery systems (DDSs). Thus DDSs development is one of the main challenges in pharmaceutical industry both to achieve tailored carrier systems based on drug features and to promote manufacturing innovations to reduce energetic resources, emissions, wastes and risks. Main functions of an ideal DDS are: to protect loaded active molecules from degradation in physiological environments; to deliver them in a controlled manner and towards specific organs or tissues, to allow the maintenance of drug concentration within therapeutic window. Smart features, such as those able to induce active molecule release upon the occurrence of specific physiological stimuli, are also desirable. Under the manufacturing point of view, the current industrial scenery is obliged to respond to the increasing market requirements and to the mandatory rules in sustainable productions such as raw material and energy savings. In this work a general framework on drug delivery systems preparation techniques is presented. In particular two sections on innovation in preparative approaches carried out are detailed. These latter involve the use of microwave and ultrasonic energy applied in the production of polymeric and lipidic delivery systems on micro- and nanometric scale. The novelties of these preparative approaches are emphasized and examples of developed drug delivery carriers, loaded with vitamins and drug mimicking siRNA, are shown.

Particulate solids have received great interest in many industrial fields for both marketing reasons and technological aspects. In this study granular systems were achieved by using a wet granulation process using hydroxypropyl methylcellulose (HPMC) and distilled water as the binder phase. Particulates with a defined size (450–2000 μm) and good flowability together with a high granulation process yield, to reduce manufacturing scrap, were produced. To this aim a bench scale low-shear rate granulator apparatus was used; three process parameters were varied (impeller rotation speed, binder volume at constant mass, and binder flow rate) and, for each parameter, three intensities have been used. HPMC granule production was planned using the Central Composite Design (CCD) statistical protocol, which allowed us to minimize the number of runs to be performed for obtaining information about the relationship between granule properties and process parameters. The produced granules were stabilized by using a dedicated dynamic drying apparatus, then separated by sieving and then characterized in terms of size and flowability properties. The results of the experimental campaign have been used to develop semi-empirical correlations between granulated product properties and process parameters. A second-order polynomial law has shown the best comparison between experimental data and model predicted values. These correlations can constitute a reliable tool to help us to know more on the effect of operative parameter changes in HMPC or similar particulate solid production.

Barba A.A., d’Amore M., Rispol M., Marra F., Lamberti G. (2014): Microwave assisted drying of banana: effects on reducing sugars and polyphenols contents. Czech J. Food Sci., 32: 369–375. The effects of microwave assisted drying on banana fruit was evaluated. Water, reducing sugars, and polyphenol contents, as well as poly-phenol-oxidase activity were evaluated along the radial and axial positions in thick slices of banana, according to a properly defined cutting and assaying protocol. The effects of the microwave-assisted drying process were compared to the convective air-assisted drying resulting faster than the conventional process. In particular, the resulting samples were homogeneous in the water content; the contents of reducing sugars were strongly decreased on drying with microwaves; the poly-phenol-oxidase was inactivated by the high temperature produced by the process and thus the polyphenols content remained practically the same as in the fresh product.

In this study, a method based on a multiple emulsions system was developed for the production of polymeric nano and micro-vectors. The possibility to apply an unified preparation technique to different polymers, such as polyesters [polycaprolactone, poly-dl-lactide, poly(dl-lactide-co-caprolactone) = 70/30] and polyacrylates [poly(methylmethacrylate–acrylic acid) = 73/27], loaded with different model molecules (budesonide, tamoxifen, and α-tocopherol) was explored. After selecting the best operating conditions, especially for emulsification and separation, the technique proved to be readily adaptable for production of both nano and micro-particles with different morphologies, depending on type of polymer, and consequently on solvent used for solubilization: nano-particles, with a round shape and a smooth surface, for polyesters, otherwise micro-particles for the polyacrylate polymer, owing to the presence of hydrophilic co-solvents, that caused both an easy coalescence between the oil and water phases, thus enlarged particles size, and a high porosity. Even the yield of encapsulation was influenced by the presence of hydrophilic co-solvents, causing a higher yield for nano-vectors. Polyesters-based nano-vectors showed release times of molecules, linked to their degradation time, higher than 8 months that make them useful to formulate injectable or implantable drug delivery systems. Polyacrylate-based micro-vectors showed an enteric behavior, interesting for designing solid pharmaceutical formulations for oral delivery. Therefore, the technique demonstrated to assure a broad application in drug delivery research.

The use of hydrogels in the preparation of controlled release pharmaceutical forms is extensively diffused. The main feature of these polymers is their ability to swell forming a gel layer when they enter in contact with fluids. Once the gel layer is formed, the drug contained in the matrix can easily diffuse ensuring a controlled release from the tablet. Measurement of water content within a hydrating matrix based on hydrogels is a key topic in the study of pharmaceutical solid dosage forms. The aim of this work is to evaluate the water content of swollen matrices composed by HPMC and theophylline both in axial and in radial direction, as a function of time, using a texture analysis. A relationship between water content and slope of the force–penetration curves has been obtained using a simplified system in which the water uptake is allowed only in radial direction, obtaining thus partially hydrated matrices with the water content varying only along the radial direction. Once the relationship has been validated, it has been applied in a more complex system in which the polymer swelling takes place in both axial and radial direction. Thus, using the texture analysis it has been possible to determine the water in each position within the hydrated matrices.

This work presents both the design of a novel process to produce microparticles with a shell–core structure and a bench scale apparatus purposely realized. The developed process was designed to respond to mandatory needs of process intensification. It involved the coupling of two emergent technologies: atomization assisted by ultrasonic energy and microwave heating. The former was used to atomize polymeric solutions; the latter was applied to stabilize the produced droplets by drying. Both operations were performed in the same vessel with the aim to have a single-pot process chamber and were carried out by a semicontinuous procedure. Basic design criteria and advantages of the ultrasonic–microwave coupled operations in the realized apparatus are presented and discussed. Results of testing and of operating runs to produce shell–core microparticles are also reported, emphasizing the main features of the produced particles.

Drying constitutes a critical unit operation in the manufacturing of pharmaceutical powders and their associated products. In this work, the drying processes of cellulose derivative (hydroxypropyl methyl cellulose, HPMC) granules were investigated. Granules of HPMC powders were produced by a wet granulation process using a hydro-alcoholic solution as binder phase, then they were dried with different drying methods based on traditional (by convective heating) and innovative (by microwave heating) techniques. To compare drying kinetics, experimental data were fitted by Lewis equation obtaining drying coefficients, and time/temperature process parameters were investigated. Microwave assisted drying showed reduced process times and, under some conditions, it allowed no drastic process temperatures. Since granular solids have a great relevance in pharmaceutical solid dosage form preparations, novel methods of drying with better performances appeared an issue of great interest for industry.

The psycho-physical state of a driver has been widely recognized as the crucial point in any issue concerning the development of models headed to improve the vehicle safety, either inherent and active, so much so that almost all the new in-vehicle technology, currently developing at a rapid rate, introduces devices to continuously monitor the driver. This paper describes the architecture of a real time, performance-based, driver monitoring system able to detect the decrease in driver performances due to driver distraction, fatigue, sleepiness and alcohol or drugs ingestion. The system processes the instantaneous lateral position of the vehicle on the road. This allows to work out an index of the lane keeping precision by means of the lateral position standard deviation (SDLP). This latter and the road environment complexity has been processed by a fuzzy inference system that has, as an output, a score reflecting the driver's ability to maintain adequate lane-tracking movements for a given road scenario. Fuzzy membership functions and inference rules has been based and optimized on data obtained on 12 subjects performing driving simulation under both baseline condition and two different cognitive overload situations induced by different secondary tasks, one with visual distraction, the other characterized by a pure cognitive load, respectively. Aim of the work is to attain to a black-box type devices that could both provide warnings or reminding in case of risky driving and encourage the driver to improve his behavior. Advantages would also come for parents of novice drivers promptly alerted for improper driving and even for the car insurance companies that could reward safe drivers.

Distraction has the potential to degrade driving performance and may have serious consequences for road safety. There is a number of research in this area and most studies concentrate on perception errors as a result of visual distraction, so much so that NHTSA has issued driver distraction guidelines to address visual and manual sources of distraction. Cognitive distraction occurs when attention is withdrawn from the processing of information necessary for the safe operation of a vehicle and seems to be qualitatively different from those associated with visual distraction. Among those sources of distraction, the cognitive one is the most difficult the to assess because of the problems associated with the observation of what a driver's brain, as opposed to hands or eyes is doing. Despite many published standards, that specify a number of methods for evaluating the visual and manual demand of secondary task interactions, there are currently no published standards that explicitly and exclusively apply to cognitive distraction. In this paper is presented an experimental framework, developed within DRIVE IN2 project (DRIVEr Monitoring: Technologies, Methodologies and IN-vehicle INnovative systems for a safe and eco-compatible driving), based on a driving simulator and car-following paradigm, with the lead vehicle that brakes suddenly when a driver in a loop system, that analyzes in real time EEG signals, detects boot very high and very low level of engagement or arousal. As driving simulator, also the Sim-Panda has been used, developed in the project, the first prototype for testing driver monitoring systems in safety conditions and in a real car. Neuro-feedback for controlling the lead vehicle is obtained by the SDK (Suite Development Kit) of Neuro-Headset Emotiv EPOC, that uses proprietary metrics, that looks for distinct brainwave characteristics that are universal in nature and do not require signature-building or individual baselining. The first is “Engagement”, characterized by increases in beta and attenuated alpha waves, and the other is “Excitement”, associated with arousal and overall physiological response. To study cognitive driver distraction, reaction time is evaluated, measuring time elapsed between sudden braking lead vehicle and response from drivers. Results are interpreted comparing brake reaction time recorded when the two metrics are booth above or below specific thresholds, obtaining indications of a driver's ability to quickly and safely respond to the sudden appearance of a threat. Reaction time measures show a great deal of consistency, and our preliminary results report that drivers responses to a lead braking vehicle are the slower, the higher is the attention they are paying to the roadway, as the drivers that are engaged in secondary-vehicle activities.

This paper presents a tandem technique, based on the combination of prilling and microwave (MW) assisted treatments, to produce biodegradable alginate carriers of piroxicam with different drug controlled release behaviours. Results showed that alginate/piroxicam beads demonstrated high encapsulation efficiency and very narrow dimensional distribution. Beads dried by MW retained shape and size distribution of the hydrated particles while drying rate was strongly increased compared to convective drying processes. Moreover, different MW irradiation regimes promoted interactions between the drug and alginate matrix, affected drug polymorphism as well as inner and surface matrix structure leading to different piroxicam release profiles. High level MW irradiation led to beads with highly porous and swellable matrix able to release piroxicam in few minutes in the intestine while convective drying produced gastro-resistant beads that exhibit sustained piroxicam release (total release in 5.5 h) in intestinal environment. On these results the tandem technique prilling/MW irradiation appears to be promising to obtain alginate carrier with tailored NSAIDs release depending on drug characteristics and MW irradiation.

In this study the feasibility of joining prilling and microwave (MW) assisted treatments as combined technique to produce controlled release alginate beads was tested. Beads were produced by prilling (laminar jet break-up) using different polymer concentrations and loaded with ketoprofen, a slightly soluble non-steroidal anti-inflammatory BCS class II drug characterized by low melting point. MW assisted treatments applied using different irradiating conditions were performed as drying/curing step. The effect of formulation conditions and process variables on drying kinetics, particle micromeritics, shape, surface and inner characteristics of the matrix as well as drug loading and drug release behaviour was studied (USP pH change method). The properties of MW dried particles were compared to those dehydrated by convective methods (room conditions and tray oven 105 °C). Results showed that MW dried ketoprofen loaded beads were obtained in a very narrow dimensional range retaining shape and size distribution of the hydrates particles. Compared to the traditional drying methods, MW treatments were able to strongly increase drying rate of the hydrated beads achieving faster and controllable dehydration kinetics. Moreover, different regimes of irradiation affected structural properties of the particles such as matrix porosity as well as the solid state of the loaded drug. DSC, X-ray and FTIR analyses indicated complex chemical interactions between the drug and polymer matrix induced by MW, related with the regime of irradiation, that contributes to the differences in release profiles. In fact, MW treatments under different time and irradiating regimes are able to modulate drug release from alginate beads; high levels of irradiation led to beads suitable for immediate release oral dosage forms whereas the lowest regime of irradiation led to beads that achieved a prolonged/sustained release of the drug till 8 h in simulated intestinal medium. This study showed that prilling in combination with microwave treatments is a useful and simple tandem technique to prepare dextran-based dried beads.

Functional extracts from Fadogia ancylantha, Melissa officinalis and Tussilago farfara posses excellent antioxidant and good antimicrobial properties. The unprocessed extracts occur as sticky and low-water-soluble materials with penetrating smell. The loading onto maltodextrins matrix, widely used by food and cosmetic industries, is often unsatisfying. The industrial products are not always enough stable to preserve the functional properties of natural compounds, also giving practical difficulties for the manufacturing. This paper reports on the plant extracts encapsulation by spray-drying in a maltodextrin/applepectin based matrix. Physicochemical and technological characteristics, organoleptic and antioxidant properties of the resulting powders, were examined and compared to both unprocessed extracts and industrial products. The selected carrier and process conditions led to stable and handling microencapsulated powder forms with improved water dissolution rate. The made up powder also masked the extracts unpleasant smell making them suitable for successive manufacturing to produce functional components for foods or nutraceuticals purposes.

Design of systems for oral controlled release of drug could take advantages from the knowledge of which phenomena take place. In this work matrices obtained by powders compression (50:50, hydroxypropyl methylcellulose, a swelling hydrogel, and theophylline, a model drug) were immersed in water at 37°C, allowing the water uptake and the drug release by lateral surface, confining the cylindrical matrices between glass slides. The tablets, after given immersion times, were withdrawn, cut in several annuli, and subsequently analyzed for the drug and the water concentration radial profiles. The data confirmed the pseudo-diffusive nature of the process, allowing to give a deep insight into the drug release process from swellable hydrogel matrices. In particular, it was confirmed the presence of nonhomogeneous gel layer, rich in water and poor in drug, with a profile of drug concentration which agrees well with a pseudo-diffusion phenomenon. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:4100–4110, 2009

The water solutions of the block copolymers PEOn-PPOm-PEOn, known as pluronics, show a complex thermal behavior, since they are liquid at low temperature (5°C), and they can give soft gel when heated at body temperature (37°C). These properties are of great interest in biomedical applications. To properly design these applications, a prerequisite is the knowledge of the thermodynamics—how much—and of the kinetics—how fast—with which these transformations take place. In this work, solutions of F127 (the copolymer for which n = 100 and m = 65) were studied by varying the concentration and the temperature and analyzing their behavior when heated under several heating rates. The studies were performed by differential scanning calorimetry (DCS) and dielectric spectroscopy. The investigations carried out under equilibrium conditions allowed us to determine the thermodynamics of the phase transitions, whereas the investigations carried out under varying conditions allowed us to quantify the kinetics of the phase transitions. Empirical models were also proposed to describe both the thermodynamics and the kinetics observed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

This paper deals with the work done by prof. Titomanlio and his group in the fields of pharmaceutical and biomedical applications of polymers. In particular, the main topics covered are: i) controlled drug release from pharmaceuticals based on hydrogel for oral delivery of drugs; ii) production and characterization of micro and nanoparticles based on stimuli-responsive polymers; iii) use of polymers for coronary stent gel-paving; iv) design and realization of novel methods (in-vitro and in-silico) to test polymer-based pharmaceuticals.

In this work the microwave absorbing properties of carbon black/silicone rubber blends were investigated in the frequency range 0.2÷6.0 GHz, varying the carbon black contents. In particular, the permittivity of the samples was measured by a network analyzer and then the experimental data were fitted as function of microwave frequency and carbon black content, e*=e*(f,C).

This work presents the design of a microwave opened applicator useful to perform the Microwave Induced Steam Distillation (MISD) process for soil remediation treatments. The prototype has been also realized and used to irradiate a 40 x 30 cm area with a given electromagnetic field distribution. Experiments carried out by in situ operations on a soil contaminated with VOC's are reported. Finally, the experimental data collected are described by a mathematical model previously proposed. © 2004 American Institute of Chemical Engineers AIChE J, 50:722–732, 2004

A new process to remediate soils contaminated with heavy metals is proposed, which is potentially useful for both in situ recovery as well as for treatments of excavated soils and sediments. This process is essentially a solvent extraction with chelating agents, but it differs from other methods proposed previously since it uses benign, environment-friendly and water-soluble solvents. In fact, their previous works have shown that the main difficulty in using conventional solvent extraction for soil remediation is the insufficient contacting between soil and solvents, due to the preferential absorption of water on the soil, and the fact that the solvents that were used were mostly water insoluble. This difficulty was overcome here by making suitable (i.e. water insoluble) solvents and complexing agents water soluble, via mixing them with water-soluble solvents. Using this method, contaminants can be extracted rapidly and efficiently. Then, contaminants as well as solvents can be separated from the water by adding a water-insoluble solvent to the system. As a result, the authors do not observe the formation of stable emulsions, which would otherwise occur when treating excavated soils and sediments. All the solvents can be chosen to be environmentally acceptable, and can subsequently be removed from themore » soil by a water wash. The new extraction process was first demonstrated by removing iron from Vesuvian soils, finding that removal was fast and thorough, even at high concentration levels. Then, the new process was applied to extract chromium (VI) from an Appalachian soil, containing 15% of organic materials, which had been previously spiked with about 25 ppm of metal ions.« less

Microencapsulation techniques are widely applied in the field of pharmaceutical production to control drugs release in time and in physiological environments. Ultrasonic-assisted atomization is a new technique to produce microencapsulated systems by a mechanical approach. Interest in this technique is due to the advantages evidenceable (low level of mechanical stress in materials, reduced energy request, reduced apparatuses size) when comparing it to more conventional techniques. In this paper, the groundwork of atomization is introduced, the role of relevant parameters in ultrasonic atomization mechanism is discussed, and correlations to predict droplets size starting from process parameters and material properties are presented and tested.

Objective: The objective of this work is to prepare oral dosage systems based on enteric materials in order to verify their possible use as Colon-Specific Drug Delivery Systems (CSDDSs).Methodology: In particular, three different copolymers of methyl-methacrylate (MMA) - acrylic acid (AA) are synthesized with increasing percentage of MMA (from 70% to 73%) and they are used to produce microparticles by the double-emulsion solvent evaporation method. The microparticles, loaded using theophylline as model drug, are then tested for drug release under varying pH to reproduce what happens in the human GI tract.Results: All the investigated systems have shown an effective pH sensitiveness: they show a good gastro-resistance, releasing the model drug only at higher pH, small intestine or colon, depending on the kind of used copolymer.Conclusion: The results confirm the usefulness of both the materials and the methods proposed in this study for colon-specific delivery applications.

The oxidation of diesel soot and amorphous carbon black, in the presence, of a copper-vanadium-potassium catalyst supported on α-alumina, was studied to investigate the influence of the carbon/catalyst initial mass ratio, R m , on the carbon reactivity. A differential flow reactor was employed to perform kinetic tests. The progress of the catalytic combustion process was followed measuring the concentrations of carbon oxides in the product stream at the reactor outlet with on-line NDIR analyzers. Experimental results conform to those obtained while operating at relatively low values, of R m for what concerns the influence of oxygen partial pressure and temperature. Furthermore, burn-off temperatures in the presence of the catalyst were lowered by ca. 300 K, and correspondingly, the apparent activation energy for the catalytic oxidation was found to be less than half with respect to the uncatalyzed combustion. A strong influence of R m on the evolution with time of the combustion process was experienced. Specifically, time profiles of reactivity obtained when R m was higher than 0.1 show a maximum whose amplitude increases as R m increases. This behavior was related to the segregation of a more-or-less large fraction of the total carbon. Following such findings, a kinetic model for carbon catalytic oxidation was proposed. It is based on the assumption that different carbon portions enter the reaction zone at different times. Model parameters were estimated by a numerical code properly adapted. A good agreement between model predictions and experimental results was found for all R m values.

Microwaves are electromagnetic radiation with wavelength ranging from 1 mm to 1 m in free space with a frequency from 300 GHz to 300 MHz, respectively. International agreements regulate the use of the different parts of the spectrum; the frequencies 915 MHz and 2.45 GHz are the most common among those dedicated to power applications for industrial, scientific and medical purposes (Metaxas & Meredith, 1983).