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| | If an existing Word - Press code is found vulnerable, Word - Press will immediately issue an update for that. It is thus, on these grounds that compel various web service provider companies to integrate the same in their packages too. * A community forum for debate of the product together with some other customers in the comments spot. In the recent years, there has been a notable rise in the number of companies hiring Indian Word - Press developers. If you liked this article and you also would like to get more info concerning [http://mysocial.ws/index.php?do=/blog/135546/an-update-on-no-hassle-worpress-methods/ wordpress backup] i implore you to visit our page. You can easily customize the titles of the posts in Word - Press blog in a way that only title comes in the new post link and not the date or category of posts. <br><br> |
| | footer = Analytical Gas Chromatography A (top) compared with Inverse Gas Chromatography B (bottom). While in gas chromatography a sample containing multiple species is separated into its components on a stationary phase, Inverse gas chromatography uses injection of a single species to probe the characteristics of a stationary phase sample.
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| | alt2 = Inverse and analytical gas chromatography
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| '''Inverse gas chromatography''' is a physical characterization technique that is used in the analysis of the surfaces of solids. Traditional GC is an [[analytical technique]].
| | These websites can be easily customized and can appear in the top rankings of the major search engines. While direct advertising is limited to few spots in your site and tied to fixed monthly payment by the advertisers, affiliate marketing can give you unlimited income as long as you can convert your traffic to sales. This plugin is a must have for anyone who is serious about using Word - Press. You can up your site's rank with the search engines by simply taking a bit of time with your site. That's a total of 180$ for each Wordpress theme if you sell 3 links and keep the designer link for your own website, or 240$ if you sell all links. <br><br>It is very easy to install Word - Press blog or website. The only problem with most is that they only offer a monthly plan, you never own the software and you can’t even install the software on your site, you must go to another website to manage your list and edit your autoresponder. Those who cannot conceive with donor eggs due to some problems can also opt for surrogacy option using the services of surrogate mother. To turn the Word - Press Plugin on, click Activate on the far right side of the list. For any web design and development assignment, this is definitely one of the key concerns, specifically for online retail outlets as well as e-commerce websites. <br><br>Google Maps Excellent navigation feature with Google Maps and latitude, for letting people who have access to your account Latitude know exactly where you are. As an example, if you are promoting a product that cures hair-loss, you most likely would not wish to target your adverts to teens. Exacting subjects in reality must be accumulated in head ahead of planning on your high quality theme. Giant business organizations can bank on enterprise solutions to incorporate latest web technologies such as content management system etc, yet some are looking for economical solutions. Wordpress template is loaded with lots of prototype that unite graphic features and content area. <br><br>Internet is not only the source for information, it is also one of the source for passive income. I'm a large fan of using Word - Press to create pretty much any sort of web page. Just download it from the website and start using the same. Extra investment in Drupal must be bypassed as value for money is what Drupal provides. Likewise, professional publishers with a multi author and editor setup often find that Word - Press lack basic user and role management capabilities. |
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| Inverse gas chromatography or IGC is a highly sensitive and versatile gas phase technique developed over 40 years ago to study the surface and bulk properties of particulate and fibrous materials. In IGC the roles of the stationary (solid) and mobile (gas or vapor) phases are inverted from traditional analytical [[gas chromatography]] (GC). In GC, a standard column is used to separate and characterize several gases and/or vapors. In IGC, a single gas or vapor (probe molecule) is injected into a column packed with the solid sample under investigation. Instead of an analytical technique, IGC is considered a materials characterization technique.
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| During an IGC experiment a pulse or constant concentration of a known gas or vapor (probe molecule) is injected down the column at a fixed carrier gas flow rate. The retention time of the probe molecule is then measured by traditional GC detectors (i.e. [[flame ionization detector]] or [[thermal conductivity detector]]). Measuring how the retention time changes as a function of probe molecule chemistry, probe molecule size, probe molecule concentration, column temperature, or carrier gas flow rate can elucidate a wide range of physic-chemical properties of the solid under investigation. Several in depth reviews of IGC have been published previously.<ref>J. Condor and C. Young, Physicochemical measurement by gas chromatography, John Wiley and Sons, Chichester, UK (1979)</ref><ref>F. Thielmann, Journal of Chromatography A. 1037 (2004) 115.</ref>
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| IGC experiments are typically carried out at infinite dilution where only small amounts of probe molecule are injected. This region is also called [[Henry's law]] region or linear region of the sorption isotherm. At infinite dilution probe-probe interactions are assumed negligible and any retention is only due to probe-solid interactions. The resulting retention volume, ''V''<sub>''R''</sub><sup>o</sup>, is given by the following equation:
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| : <math> V_R^\circ = \frac{j}{m} F(t_R - t_o) \frac{T}{273.15} </math>
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| where ''j'' is the James–Martin pressure drop correction, ''m'' is the sample mass, ''F'' is the carrier gas flow rate at standard temperature and pressure, ''t''<sub>''R''</sub> is the gross retention time for the injected probe, ''t''<sub>o</sub> is the retention time for a non-interaction probe (i.e. dead-time), and ''T'' is the absolute temperature.
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| ==Surface energy determination==
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| The main application of IGC is to measure the [[surface energy]] of solids (fibers, particulates, and films). [[Surface energy]] is defined as the amount of energy required to create a unit area of a solid surface; analogous to surface tension of a liquid. Also, the [[surface energy]] can be defined as the excess energy at the surface of a material compared to the bulk. The surface energy (γ) is directly related to the thermodynamic work of adhesion (''W''<sub>adh</sub>) between two materials as given by the following equation: | |
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| : <math> W_\mathrm{adh} = 2(\gamma_1 \gamma_2)^{1/2} </math>
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| where 1 and 2 represent the two components in the composite or blend. When determining if two materials will adhere it is common to compare the work of adhesion with the work of cohesion, ''W''<sub>coh</sub> = 2''γ''. If the work of adhesion is greater than the work of cohesion, then the two materials are thermodynamically favored to adhere.
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| Surface energies are commonly measured by [[contact angle]] methods. However, these methods are ideally designed for flat, uniform surfaces. For [[contact angle]] measurements on powders, they are typically compressed or adhered to a substrate which can effectively change the surface characteristics of the powder. Alternatively, the Washburn method can be used, but this has been shown to be affected by column packing, particle size, and pore geometry.<ref>J. Dove, G. Buckton, and C. Doherty, International Journal of Pharmaceutics. 138 (1996) 199–206.</ref> IGC is a gas phase technique, thus is not subject to the above limitations of the liquid phase techniques.
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| To measure the solid surface energy by IGC a series of injections using different probe molecules is performed at defined column conditions. It is possible to ascertain both the dispersive component of the [[surface energy]] and [[acid-base]] properties via IGC. For the dispersive surface energy, the retention volumes for a series of n-alkane vapors (i.e. decane, nonane, octane, heptanes, etc.) are measured. The Dorris and Gray.<ref>G.M. Doris and D.G. Gray, Journal of Colloids and Interfacial Science. 56 (1964) 353.</ref> or Schultz <ref>J. Schultz, L. Lavielle, and C. Martin, Journal of Adhesion. 77 (1980) 353–362.</ref> methods can then be used to calculate the dispersive [[surface energy]]. Retention volumes for polar probes (i.e. toluene, [[ethyl acetate]], [[acetone]], [[ethanol]], [[acetonitrile]], [[chloroform]], [[dichloromethane]], etc.) can then be used to determine the acid-base characteristics of the solid using either the Gutmann,<ref>V. Gutmann, Coordination Chemistry Reviews. 2 (1966) 239–256.</ref> or Good-van Oss theory.<ref>C.J. van Oss, R.J. Good, and M.K. Chaudhury, Langmuir. 4 (1988) 884–891.</ref> | |
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| Other parameters accessible by IGC include: heats of sorption [1], adsorption isotherms,<ref>E. Cremer and H. Huber, in Gas Chromatography., ed. N. Brenner, et al., Academic Press, New York (1962) p 169.</ref> energetic heterogeneity profiles,<ref>P.P. Yla-Maihaniemi, J.Y.Y. Heng, F. Thielmann, and D.R. Williams, Langmuir. 24 (2008) 9551–9557.</ref><ref>F. Thielmann, D.J. Burnett, and J.Y.Y. Heng, Drug Development and Industrial Pharmacy. 33 (2007) 1240–1253.</ref> diffusion coefficients,<ref>J. van Deemter, F.J. Zuiderweg, and A. Klinkenberg, Chemical Engineering Science. 5 (1965) 271.</ref> [[glass transition]] temperatures [1],<ref>G. Buckton, A. Ambarkhane, and K. Pincott, Pharmaceutical Research. 21 (2004) 1554–1557.</ref> Hildebrand <ref>14 D. Benczedi, D, I. Tomka, and F. Escher, Macromolecules. 31 (1998) 3055.</ref><ref>G. DiPaola and J.E. Guillet, Macromolecules. 11 (1978) 228.</ref> and Hansen <ref>K. Adamska and A. Voelkel, International Journal of Pharmaceutics. 304 (2005) 11–17.</ref> solubility parameters, and crosslink densities.<ref>G.J. Price, K.S. Siow, and J.E. Guillet, Macromolecules. 22 (1989) 3116–3119.</ref>
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| ===Applications===
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| IGC experiments have applications over a wide range of industries. Both surface and bulk properties obtained from IGC can yield vital information for materials ranging from pharmaceuticals to [[carbon nanotubes]]. Although surface energy experiments are most common, there are a wide range of experimental parameters that can be controlled in IGC, thus allowing the determination of a variety of sample parameters. The below sections highlight how IGC experiments are utilized in several industries.
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| ===Polymers and coatings===
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| IGC has been used extensively for the characterization of polymer films, beads, and powders. For instance, IGC was used to study surface properties and interactions amongst components in paint formulations.<ref>A. Ziani, R. Xu, H.P. Schreiber, and T. Kobayashi, Journal of Coatings Technology. 71 (1999) 53–60.</ref> Also, IGC has been used to investigate the degree of crosslinking for [[ethylene-propylene rubbers]] using the [[Flory–Rehner equation]] [17]. Additionally, IGC is a sensitive technique for the detection and determination of first and second order phase transitions like melting and [[glass transition]] temperatures of [[polymers]].<ref>A. Lavole and J.E. Guillet, Macromolecules. 2 (1969) 443.</ref> Although other techniques like [[dynamic scanning calorimetry]] are capable of measuring these transition temperatures, IGC has the capability of [[glass transition]] temperatures as a function of [[relative humidity]].<ref>F. Thielmann and D.R. Williams, Deutsche Lebensmittel-Rundschau. 96 (2000) 255–257.</ref>
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| ===Pharmaceuticals===
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| The increasing sophistication of pharmaceutical materials has necessitated the use for more sensitive, [[thermodynamic]] based techniques for materials characterization. For these reasons, IGC, has seen increased use throughout the pharmaceutical industry. Applications include polymorph characterization,<ref>H.H.Y. Tong, B.Y. Shekunov, P. York, and A.H.L Chow, Pharmaceutical Research. 19 (2002) 640–648.</ref> affect of processing steps like milling,<ref>J.Y.Y. Heng, F. Thielmann, and D.R. Williams, Pharmaceutical Research, 23 (2006) 1918–1927.</ref> and drug-carrier interactions for dry powder formulations.<ref>J. Feeley, P. York, B. Sumby, and H. Dicks, International Journal of Pharmaceutics. 172 (1998) 89–96.</ref> In other studies, IGC was used to relate [[surface energy]] and acid-base values with [[triboelectric charging]] <ref>N. Ahfat, G. Buckton, R. Burrows, and M. Ticehurst, European Journal of Pharmaceutical Science. 9 (2000) 271–276.</ref> and differentiate the [[crystalline]] and [[amorphous]] phases [23].
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| ===Fibers===
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| [[Surface energy]] values obtained by IGC have been used extensively on fibrous materials including textiles,<ref>E. Cantergiani and D. Benczedi, Journal of Chromatography A. 969 (2002) 103–110.</ref> natural fibers,<ref>J.Y.Y. Heng, D.F. Pears, F. Thielmann, T. Lampke, and A. Bismark, Composite Interfaces. 14 (2007) 581–604.</ref> glass fibers,<ref>K. Tsutsumi and T. Ohsuga, Colloid and Polymer Science. 268 (1990) 38–44.</ref> and [[carbon fibers]].<ref>L. Lavielle and J. Schultz, Langmuir. 7 (1991) 978–981.</ref> Most of these and other related studies investigating the surface energy of fibers are focusing on the use of these fibers in composites. Ultimately, the changes in surface energy can be related to composite performance via the works of adhesion and cohesion discussed previously.
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| ===Nanomaterials===
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| Similar to fibers, [[nanomaterials]] like [[carbon nanotubes]], nanoclays, and nanosilicas are being used as composite reinforcement agents. Therefore, the surface energy and surface treatment of these materials has been actively studied by IGC. For instance, IGC has been used to study the surface activity of nanosilica, nanohematite, and nanogeoethite.<ref>K. Batko and A. Voelkel, Journal of Colloid and Interface Science. 315 (2007) 768–771.</ref> Further, IGC was used to characterize the surface of as received and modified carbon nanotubes.<ref>R. Menzel, A. Lee, A. Bismarck, and M.S.P. Shaffer, Langmuir. (2009) in press.</ref>
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| ===Other===
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| Other applications for IGC include paper-toner adhesion,<ref>J. Borch, Journal of Adhesion Science and Technology. 5 (1991) 523–541.</ref> wood composites,<ref>R.H. Mills, D.J. Gardner, and R. Wimmer. Journal of Applied Polymer Science. 110 (2008) 3880–3888.
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| </ref> porous materials [3], and food materials.<ref>Q. Zhou and K.R. Cadwallader. Journal of Agricultural and Food Chemistry. 54 (2006) 1838–1843.</ref>
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| ==See also==
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| *[[Surface energy]]
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| *[[Adhesion]]
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| *[[Wetting]]
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| *[[Wetting transition]]
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| *[[Material characterization]]
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| *[[Sessile drop technique]]
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| ==References==
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| {{reflist}}
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| {{DEFAULTSORT:Inverse Gas Chromatography}}
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| [[Category:Gas chromatography]]
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If an existing Word - Press code is found vulnerable, Word - Press will immediately issue an update for that. It is thus, on these grounds that compel various web service provider companies to integrate the same in their packages too. * A community forum for debate of the product together with some other customers in the comments spot. In the recent years, there has been a notable rise in the number of companies hiring Indian Word - Press developers. If you liked this article and you also would like to get more info concerning wordpress backup i implore you to visit our page. You can easily customize the titles of the posts in Word - Press blog in a way that only title comes in the new post link and not the date or category of posts.
These websites can be easily customized and can appear in the top rankings of the major search engines. While direct advertising is limited to few spots in your site and tied to fixed monthly payment by the advertisers, affiliate marketing can give you unlimited income as long as you can convert your traffic to sales. This plugin is a must have for anyone who is serious about using Word - Press. You can up your site's rank with the search engines by simply taking a bit of time with your site. That's a total of 180$ for each Wordpress theme if you sell 3 links and keep the designer link for your own website, or 240$ if you sell all links.
It is very easy to install Word - Press blog or website. The only problem with most is that they only offer a monthly plan, you never own the software and you can’t even install the software on your site, you must go to another website to manage your list and edit your autoresponder. Those who cannot conceive with donor eggs due to some problems can also opt for surrogacy option using the services of surrogate mother. To turn the Word - Press Plugin on, click Activate on the far right side of the list. For any web design and development assignment, this is definitely one of the key concerns, specifically for online retail outlets as well as e-commerce websites.
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Internet is not only the source for information, it is also one of the source for passive income. I'm a large fan of using Word - Press to create pretty much any sort of web page. Just download it from the website and start using the same. Extra investment in Drupal must be bypassed as value for money is what Drupal provides. Likewise, professional publishers with a multi author and editor setup often find that Word - Press lack basic user and role management capabilities.