Piercing

Bard A J, Fan F F, Pierce D T, Unwin P R, Wipf D O and Zhou F 1991 Chemicai imaging of surfaces with the scanning eiectrochemicai microscope Science 254 68... 

Pierce D W, Hom-Booher N and Vale R D 1997 Imaging individual green fluorescent proteins Nature 388 338... 

Vale R D, Funatsu T, Pierce D W, Romberg L, Harada Y and Yanagida T 1996 Direct observation of single kinesin molecules moving along microtubules/Vafuro 380 451-3... 

This type of filtration is almost invariably performed with the aid of a Buchner flask and funnel, by means of which a rapid and almost complete separation can be obtained. The Buchner flask A (Fig. 4) consists of a simple thick-walled conical flask with a short side-arm for connection to a water-pump. Into the neck of the flask is fitted the Buchner funnel B which consists usually of a cylindrical porcelain funnel, the bed of which is pierced by a... 

A metal cylinder A contains two small holes. Into one of these the thermometer is placed and into the other (arranged centrally) is placed the melting-point tube. The cylinder is pierced by a hori-2ontaI tunnel so the melting-point tube can be observed during heating. A lens is... 

Fig. 2.26 Comparison of a number of standard isotherms of nitrogen at 77 K, plotted as n/n against pip . O, Shnll x, Pierce , de Boer el , Cranston and Inkley. ...

A procedure involving only the wall area and based on the cylindrical pore model was put forward by Pierce in 1953. Though simple in principle, it entails numerous arithmetical steps the nature of which will be gathered from Table 3.3 this table is an extract from a fuller work sheet based on the Pierce method as slightly recast by Orr and DallaValle, and applied to the desorption branch of the isotherm of a particular porous silica. 

Calculation of pore size distribution (Method of Pierce, also of Orr and DallaValle )... 

Further evidence pointing in the same direction was provided by Pierce, Wiley and Smith, who found that on steam activation of a particular char at 900°C the saturation uptake increased three-fold, yet the isotherm was still of Type I. They argued that even if the width of the pores was only two molecular diameters before activation, it would increase, by removal of oxides, during the activation so that the second Type I isotherm would correspond to pores more than two molecular diameters wide. (The alternative explanation, that activation produced new pores of the same width as the old, seems unlikely.)... 

These various considerations led Pierce, Wiley and Smith in 1949, and independently, Dubinin, to postulate that in very fine pores the mechanism of adsorption is pore filling rather than surface coverage. Thus the plateau of the Type 1 isotherm represents the filling up of the pores with adsorbate by a process similar to but not identical with capillary condensation, rather than a layer-by-layer building up of a film on the pore walls. 

For GC, the injector is most frequently a small heated space attached to the start of the column. A sample of the mixture to be analyzed is injected into this space by use of a syringe, which pierces a rubber septum. The injector needs to be hot enough to immediately vaporize the sample, which is then swept onto the head of the column by the mobile gas phase. Generally, the injector is kept at a temperature 50 C higher than is the column oven. Variants on this principle are in use, in particular the split/splitless injector. This injector can be used in a splitless mode, in which the entire injected sample goes onto the column, or in a split mode, in which only part of the sample goes onto the column, the remainder vented to atmosphere. For other less usual forms of injector, a specialist book on GC should be consulted. 

Pie filling Pierce-Smith converter Pierre Cardin Piezoelectric Piezoelectric atomizer... 

R. J. Pierce andj. W. Bozzelli, Paper presented at the 45th Annual Technical Conference of the Society of Plastics Engineers, May 1987, p. 19. 

J. Green, in M. Lewin, S. M. Adas, and E. M. Pierce, eds., Flame-Retardant Polymeric Materials, Vol. 3, Plenum Press, New York, 1982, Chapt. 1. 

---