Cold-stage imaging

In contrast transmission electron microscopy (TEM) can in skilled hands yield detailed quantitative data on pore structure, and can even provide valuable information on the wet state of resins by plunge freezing such samples and microtom-ing on a cold stage [105]. To obtain quantitative information it is necessary to use advanced image analysis methodology which is extremely powerful [106]. Unfortunately the approach is time consuming and costly and can rarely be applied routinely in morphology studies. 

Microscopic analysis is the only method available for estimating ice crystal size in ice cream. Light microscopy, equipped with cold stage and image analysis, may be used for this purpose54. Low temperature scanning electron microscopy may also be used55. 

In these studies a unique ultrasonic cold stage was used to examine the effect of ultrasoimd on ice crystallization. The experimental system was composed of three principal components (1) an ultrasonic cold stage, (2) a temperature control system, and (3) a microscope and imaging setup. The ultrasonic cold stage allowed a thin sample of liquid to be subjected to an alternating acoustic pressure. 

Fig. 4.16 TEM micrographs of latex particles are shown of images taken in a microscope with a cold stage (A) and following both staining with PTA and using the cold stage (B).

Fig. 5.76 TEM images of poly(ethyl acrylate) latex particles taken using a cold stage (A) has indistinct particle edges, whereas the same latex negatively stained with 2% aqueous PTA has clearly imaged edges (B). (From O. L. Shaffer, impublished [364].)...

For information on properties of cantilevers, the second edition of Sarid s book is an excellent choice [102]. Garcia and Perez [103] have reviewed the theory behind dynamic imaging modes of intermittent contact AFM (IC-AFM) [104] and noncontact AFM (NC-AFM) [105]. The influence of the tip shape in imaging has been reviewed by Villarrubia [106]. The application of SPM to polymer ultrastructure and crystallinity has been reviewed by many including the work of Reneker et al. [107], Lotz et al. [108,109], Hobbs et al. [110], and Magonov and Yerina [111]. Some of the ultrastructural studies have been conducted using hot/cold stages to study in situ crystallization [112-114]. 

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