Areas of progress

The thirtieth volume in the series marks the completion of over three decades of endeavour by more than 170 contributors from laboratories in 19 different countries to bring over 120 selected areas of progress in physical organic chemical research to the attention of readers worldwide. Its publication provides an occasion to thank them and also to reflect on the changing times and priorities of research in this field, and to contemplate the future. 

An important area of progress in zirconacyclopentadiene chemistry has been the heteroatom transfer developed by Fagan and Nugent, leading to five-membered heterocydes (Eq. 2.19) [26],... 

Another important area of progress is the enlargement of the scope of the structure of aqueous aggregates. The bilayer membrane formed from dialkyl amphiphiles belongs to a new class of the aqueous aggregate, totally different from the conventional surfactant micelle. A trialkylammonium compound gives yet another type of aggregation. 

The second area of progressive development will be in the area of very specialized data collection mediums. We foresee a major extension in the area of direct data input using interactive video terminals built within the sensory evaluation booths. Although this will take a fairly extensive development in the area of software, the gains to be reaped by the development will far exceed the development costs itself. A large area of research has yet to be conducted concerning the application of microcomputers in sensory analysis as a data collection tool. Studies of inherent bias, effects on response freedom etc. will have to be undertaken in order to properly evaluate the computer as a data acquisition tool. Biases based on the way the software... 

This overview of the ZP3-dependent acrosome reaction mechanisms underscores areas of progress and major gaps in our understanding. The principle obstacles to understanding this process have historically followed from the fact that sperm are small, polarized cells. As aresult, identification and purification of signaling molecules has been difficult. However, the application of sensitive biophysical and biochemical methods has permitted rapid progress in recent years. 

Apart from the reduction in the scale of the quantities separated, two other areas of progression should be noted ... 

Thin-layer chromatography today is a dynamically developing modem analytic method. Areas of progress include increase of the spectrum of selectivity, improvement of efficiency, and in certain cases simplification of handling. The discussion of bulk sorbents and precoated layers above is not a complete enumeration of all possibilities e.g., the different carriers for the layers (glass plates, aluminum, or plastic sheets) are not shown explicitly. In addition, special plates with very restricted applicability are not discussed. 

Several areas of halide chemistry have recently been active or significantly altered by recent results. The area of preparative methods has been surprisingly active and has expanded to include crystal growth procedures. Substantial progress has been made in the definition and refinement of structural properties and in the expansion of thermodynamic data. Other important areas of progress include the identification and characterization of both novel reduced halides and interesting gas phase species. 

This review gives a brief account of recent progress in molecular sieve synthesis, characterization, and catalysis. The term molecular sieve, instead of zeolite, is used here with the intention to reflect the expansion of the materials base from metal aluminosilicate zeolites to microporous crystals of new compositions. Completeness is not the objective of this review. The intention is, rather, to point to principal areas of progress, using representative examples from the literature. 

The principal areas of progress in molecular sieve characterization are NMR spectroscopy, electron microscopy. X-ray crystallography, and far-infrared spectroscopy. 

---