Interface pressure- programmed

For all MicroSYNTH systems, reactions are monitored through an external control terminal utilizing the Easy WAVE software packages. The runs can be controlled by adjusting either the temperature, the pressure, or the microwave power output in a defined program of up to ten steps. The software enables on-line modification of any method parameter and the reaction process is monitored through an appropriate graphical interface. An included solvent library and electronic lab journal feature simplifies the experimental documentation. 

Recently all of the temperature, pressure, and time controls have been replaced with a single microprocessor-based controller. A number of these are available and they allow for complex pressure and temperature curves to be programmed with multiple soaking levels and variables that can be chosen. Built-in memories recall previous programs and cassettes can store them on the shelf. Interfaces can connect with a central host computer for data collection or actual machine setup and supervision. The result is more flexible, more exacting, and easier to control modern molding equipment (Chapter 3). 

In order to facilitate rapid melt viscosity measurement and data analysis a modified Gflttfert capillary rheometer has been interfaced to a Hewlett-Packard data acquisition system. All test parameters (temperature, barrel pressure, etc) are monitored automatically and the data is stored on magnetic tape. After testing is complete, raw data is entered into an analysis program used to compute tables and draw plots of shear stress, shear rate, and apparent viscosity. Examples of the application of this system to commercial polymers are discussed. 

Layered nanostructures can be deposited from the electrochemical environment by applying a time dependent voltage program to the working electrode (5) or by using a sequential deposition scheme such as electrochemical atomic layer epitaxy (EC-ALE) (6-10). In EC-ALE, a surface-limited electrochemical reaction, such as underpotential deposition (upd), is used to synthesize a binary compound by successive deposition of each element from its respective solution precursor. EC-ALE is an attractive electrosynthetic alternative to conventional deposition methods that is inexpensive, operates at ambient temperature and pressure and provides precise film thickness control. This technique promises to overcome many problems associated with other electrosynthetic approaches, such as the formation of highly polycrystalline deposits and interfacial interdiffusion. For example, we have recently used EC-ALE to fabricate stable semiconductor heterojunctions with extremely abrupt interfaces (11). 

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