For a tobacco heating product (THP), which heats rather than burns tobacco, the emissions of toxicants in the aerosol were compared with those in cigarette smoke under a machine-puffing regimen of puff volume 55 ml, puff duration 2 s and puff interval 30 s. The list of toxicants included those proposed by Health Canada, the World Health Organization Study Group on Tobacco Product Regulation (TobReg), the US Food and Drug Administration and possible thermal breakdown products. In comparison to the University of Kentucky 3R4F reference cigarette the toxicant levels in the THP1.0 emissions were significantly reduced across all chemical classes. For the nine toxicants proposed by TobReg for mandated reduction in cigarette emissions, the mean reductions in THP1.0 aerosol were 90.6-99.9% per consumable with an overall average reduction of 97.1%. For the abbreviated list of harmful and potentially harmful constituents of smoke specified by the US Food and Drug Administration Tobacco Products Scientific Advisory Committee for reporting in cigarette smoke (excluding nicotine), reductions in the aerosol of THP1.0 were 84.6-99.9% per consumable with an overall average reduction of 97.5%.
Continued innovations in the polymer industry have made polymer surface modification methods a subject of intense research. The importance and necessity of surface modification of plastics are explained, and the advantages of physical surface treatments over the less-sophisticated chemical methods are outlined. Currently available physical surface modification methods for food packaging polymers are reviewed from the food packaging perspective. These physical surface modification methods include flame, corona discharge, UV, gamma-ray, electron beam, ion beam, plasma, and laser treatments. The principle of operation of each method is briefly described, and the advantages and disadvantages of each technique are cited. The extent to which each of these methods can produce the specific modifications desired is discussed. Furthermore, the effects of each treatment on barrier, mechanical, and adhesion properties of food packaging polymers are also examined. Finally, an overview of economic aspects of sophisticated surface modification techniques, including ion beam, plasma, and laser treatments, is presented.
From the early century Nobel Prize winning (1923) experiments with charged oil droplets, resulting in the discovery of the elementary electronic charge by Robert Millikan, to the early 215t century Nobel Prize (2002) awarded to John Feim for his invention of electrospray ionization mass spectroscopy and its applications to proteomics, electrostatic processes have been successfully applied to many areas of industry and medicine. Generation, transport, deposition, separation, analysis, and control of charged particles involved in the four states of matter: solid, liquid, gas, and plasma are of interest in many industrial and biomedical processes. In this paper, we briefly discuss some of the applications and research needs involving charged particles in industrial and medical applications including: (1) Generation and deposition of unipolarly charged dry powder without the presence of ions or excessive ozone, (2) Control of tribocharging process for consistent and reliable charging, (3) Thin film (< 25 i.m) powder coating and Powder coating on insulative surfaces, (4) Fluidization and dispersion of fine powders, (5) Mitigation of Mars dust, (6) Effect of particle charge on the lung deposition of inhaled medical aerosols, (7) Nanoparticle deposition, and (8) Plasma/Corona discharge https://ntrs.nasa.gov/search.jsp?R=20120003223 2018-05-10T11:56:16+00:00Z
Recent advances in nanotechnology offer nano sized or nanostructured pharmaceutical particles, being as small as the size of cells such as receptors or nucleic acids, which can be engineered to provide enhanced efficacy, solubility, or biocompatibility, and to administer at much lower dosages. However, industrial production of these particles is still challenging. Among different techniques, aerosol based ones might be favorable since they are considered as contamination free processes and do not interfere with complex molecules of drugs. We, in this review, consider liquid atomization, where droplet formation is followed by conversion into solid particles. The best candidate is a method, which not only produces mono sized droplets with a diameter smaller than the inside nozzle diameter but also generates small enough start up sizes. Such a method is found in: Electro-Hydrodynamic Atomization (EHDA) or Electrospraying. Electrospraying is now a well practiced technique for producing very fine monodisperse droplets from a liquid under the influence of electrical forces. By controlling the liquid flow rate and the electrostatic potential between the liquid and the counter electrode, droplets within a narrow size range can be generated, while the mean diameter ranges from nanometers up to several micrometers. Besides generating monodisperse droplets, electrosprays are also distinguished by their self dispersing nature due to Coulomb repulsion, the possibility of trajectory control of the produced charged droplets, and the reduced risk of nozzle clogging due to the large size of the orifice compared to the size of the droplets. We will discuss different spraying modes depending on the strength of the electric stresses relative to the surface tension stress on the liquid surface and on the inertia of the liquid leaving the nozzle. However, for the production of monodisperse nanoparticles the so called cone-jet mode will be explained in depth. Scaling laws can be used to estimate the operational conditions for producing nanodroplets of a certain size. Hartman and coworkers refined the scaling laws for EHDA in the Cone-Jet mode using theoretically derived models for the cone, jet, and droplet size. By means of several examples, a generic way to produce nanoparticles, via scaling laws, from a multitude of different precursors will be discussed. Several examples of medicine particles with different properties made by EHDA will be given. Processes based on bipolar coagulation, where oppositely charged carrier particles and nano sized active agents are brought together to form composite drugs, will be discussed. Finally some attention will be given to challenges on out-scaling of EHDA methods for industrial production.
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