Field-responsive materials

More recently, increasing interest has been devoted to exploration of multirespon-sive magnetic polymers, which exhibit sensitivity to several external stimuli. Micro- and nanospheres that combine both magnetic, temperature, and pH sensitivity were also elaborated and studied. These new results provide novel possibilities for preparation of more complex magnetic field-responsive materials like membranes with on/off switching control. 

Suslick, K. S. Chen, C.-T. Polym. Mater. Sci. Eng. 1990, 63, 111. Chen, C.-T. Porphyrins and Metalloporphyrins as Field Responsive Materials, University of Illinois at Urbana-Champaign Urbana, IL, 1992. 

Many experimental results have suggested that the conformational modification of the polythiophene backbone can be induced through order-disorder transitions of the side-chains [59]. It was then postulated that various external stimuli could pertuib the side-chain organization and consequently induce some chromic effects. These side-chain transitions can be induced by heating (thermochromism), varying the solvent quality (solvatochromism), ion complexation (ionochromism), photo-induced isomerization (photochromism) and affinity binding (affinity or biochromism) giving rise to a novel class of field responsive materials. 

PhotMefractive (PR) polymers are multifunctional field-responsive materials that combine photoconducting and electro-optic propoties. hi this charter, we will review the basics of photorefiactivity in polymers and liquid crystals and describe recent advances that have led to highly efficient materials. These advances in material development enable a variety of photonic aiqilications including optical correlators for security verification. 

Phule, P.P. and Ginder, J.M. 1998. The materials science of field-responsive materials. MRS Bull. 23 ... 

Raw materials (cGMP controls) Inspection of the establishment for the drug substance and review of data on raw materials to determine compliance with cGMP requirements is a Field responsibility. 

Raw materials (tests, methods and specifications) Audit of the data submitted for CDER review in the application is a Field responsibility. CDER chemists are responsible for the scientific review of the associated data, evaluations of the adequacy of the submitted data, and ultimate approval of the tests, methods, and specifications established for the raw materials in the application. 

We are optimistic that the field of semiconductor photochemistry will lead to new materials, devices, and techniques to solve many important problems facing our society, including development of renewable energy sources, methods for environmental remediation, and advanced sensor and monitoring technologies. The chapters herein are up-to-date, comprehensive, and authoritative. The book is a valuable resource for both students and scientists working in the broad area of optically responsive materials based on nanostructured semiconductors. 

In such measurements, it is very important to specify the excitation level and the frequency at which the measurement was made. As can be seen in Figure 2.2, even when the sample hysteresis is low, the piezoelectric coefficients of materials are field-dependent quantities. Thus, there is some curvature of the strain-field response. Typically the low-field response is defined as the piezoelectric coefficient measured near the origin (often at field levels < 1 / 10th... 

The detector of GB-A-2260218 comprises a photo-responsive material and an array of planar antennae formed thereon which concentrate radiation in fringe fields at antenna edges and extremities interacting with the photo-responsive material. This structure allows the photo-responsive material to be formed thinly, which reduces volume-dependent generation-recombination noise with consequent increase in responsivity and detectivity. Furthermore, reduced element thickness allows higher element resistance. 

In practice we usually think about the response of a material to oscillatory fields— absorption, reflection, transmission, refraction, etc. We learn to connect the frequencies at which electromagnetic waves are absorbed with the natural motions of the material. If necessary, we can use oscillatory-field responses to know what the material would do in nonoscillatory fields. 

In the limit of very high applied frequencies, the constituent material charges can no longer keep up with the applied field. The material response will be the same as that of a vacuum ... 

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