Multimode applicators

These applicators are widely used in the domestic sector and have also found many applications in industry. Multimode applicators are very versatile in that they can accept a wide range of material loads of different effective loss factors and sizes. 

To improve the uniformity of heating two basic methods are used. A turntable which rotates at a constant speed can be used to move the load successively through the nodes and antinodes. Alternatively, a mode stirrer can be used. This is a structure such as a metallic multiblade fan which perturbs the electromagnetic field continuously by its rotation inside the multimode oven. It is quite common to find both of these techniques in operation. 

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The direct melt process economically produces thick optical fibers (250-400 pm in diam.), which is advantageous, but their relatively high attenuation (3-20 dB/km) due to impurities is not. As a result, they are limited to short distance multimode applications. 

Consequently, we consider that the industrial scale technological management of microwave assisted chemical reaction is no compatible with batch reactors coupled with multimode applicators. Some typical processes with a systematic decrease of the dielectric losses of the concerned reactant, such as filtration and drying of mineral or pharmaceutical powders are compatible with multimode applicators. To our knowledge, the only industrial batch microwave device is the microwave variant of the Turbosphere ( all in one solution mixer/granulator/dryer designed by Moritz... 

Multimode applicator An applicator dimension is large in relation to the wave legth of incident microwaves. 

CAs are often encapsulated in order to protea the payload from the body and vice versa. An outer shell provides a barrier between the host and the agent, as well as a physical barrier to prevent erosion or diffusion of the material while in circulation. Additionally, encapsulation may change the pharmacokinetics of the agent, while also providing a platform for mulrifimcrional agents for targeting, dmg delivery, and multimodal applications. ... 

The high sensitivity found in PET agents is frequently combined with the high spatial and temporal resolution of MRI in the synthesis of multimodal probes. With respect to multimodal applications using PET, significant effort... 

Abstract. This work introduces the design of a multimodal application allowing the user to sculpt 3D medical data. We are considering interaction modalities such as blowing and gesture to segment the 3D data visualized. Besides we present a multimodal platform for the rapid development of multimodal interactive systems as a central tool for an iterative user-centered design process. 

Bera D, Qian L, Tseng TK, Holloway PH (2010) Quantum dots and their multimodal applications a review. Materials 3 2260-2345... 

Figure 27 Typical modes in a multimode applicator. (After ref 14).

This spread in velocity is called modal dispersion and is the principle limit to the use of multimode fibres for long-distance transmissive applications. 

Although 0-switching produces shortened pulses, typically 10-200 ns long, if we require pulses in the picosecond (10 s) or femtosecond (10 s) range the technique of mode locking may be used. This technique is applicable only to multimode operation of a laser and involves exciting many axial cavity modes but with the correct amplitude and phase relationship. The amplitudes and phases of the various modes are normally quite random. 

CVD yields fibers with low loss (< 0.5 dB/km) which are suitable for both mono- and multimode long-distance applications. It has emerged as the strongest technology for high-volume, low- cost production. ]... 

Advanced computerisation and sensorisation and developments in the field of multielement optical detectors (CCD and PDA) and fibre optic remote spectroscopy have added modularity and flexibility. Silica-silica fibres used for spectroscopy applications are multimode with core diameters from 50 to 1000 p,m. The application of new technologies to optical instrumentation (e.g. improved gratings in spectrographs, the use of... 

Since the early applications of microwave-assisted synthesis were based on the use of domestic multimode microwave ovens, the primary focus in the development of dedicated microwave instruments was inevitably the improvement of multimode... 

Microwave-assisted reactions allow rapid product generation in high yield under uniform conditions. Therefore, they should be ideally suited for parallel synthesis applications. The first example of parallel reactions carried out under microwave irradiation conditions involved the nucleophilic substitution of an alkyl iodide with 60 diverse piperidine or piperazine derivatives (Scheme 4.22) [76]. Reactions were carried out in a multimode microwave reactor in individual sealed polypropylene vials using acetonitrile as solvent. Screening of the resulting 2-aminothiazole library in a herpes simplex virus-1 (HSV-1) assay led to three confirmed hits, demonstrating the potential of this method for rapid lead optimization. 

For general solid-phase reactions in a dedicated multimode instrument, an adaptable filtration unit is available from Anton Paar (see Fig. 3.18). This tool is connected to the appropriate reaction vessel by a simple screw cap and after turning over the vessel, the resin is filtered by applying a slight pressure of up to 5 bar. The resin can then be used for further reaction sequences or cleavage steps in the same reaction vessel without any material loss. However, at the time of writing, no applications of this system for solid-phase synthesis had been reported. 

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