Alternating irradiation method

Harada H (2001) Isolation of hydrogen from water and/or artificial seawater by sonophoto-catalysis using alternating irradiation method. Int J Hydrogen Energy 26(4) 303-307... 

H. Harada (2001)Isolation of hydrogen from water and for artificial seawater by sono-photocatalysis using alternating irradiation method Int J. Hydrogen Energy, 26 3003-2007... 

Fig. 12.12 Isolation of H2 and 02 by sonophotocatalytic reaction using alternating irradiation method.

Lack of cooling during preparation of the Simmons-Smith organozinc reagent caused the reaction to erupt. The possibly pyrophoric nature of organozinc compounds and the presence of ether presents a severe fire hazard [1]. An alternative, safer method of activating the zinc for the reaction involves use of ultrasonic irradiation rather than the copper-zinc couple [2]. 

Illuminated alternately with UV and visible light, the porphyrinic dithienylethene underwent a reversible photoisomerization reaction (Scheme 1). Meanwhile, the fluorescence intensity of the porphyrin macrocycles could be regulated by alternate irradiation with UV (313nm) and visible light (longer than 480 nm). Moreover, the selective excitation band of the fluorophore was beyond the spectral band which could induce the photoisomerization reaction. Therefore, the authors asserted that this compound could act as a system for reversible data processing using fluorescence as the non-destructive detection method. 

An absolute method for molecular weight determination is matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF) (Kona et al., 2005 Creel, 1993 Nielsen, 1999 Cho et al., 2001). The sample is dispersed in a UV-absorbing matrix (e.g., trans -cinnamic acid or 2,5-dihydroxybennzoic acid). Irradiation with a UV laser induces evaporation of ionized polymer chains, which are then detected using TOF. The technique requires relatively narrow MWD samples. Alternative ionization methods have been employed, such as electrospray ionization mass spectrometry (ESI-MS), which may have advantages for certain polymer end groups (Vana et al., 2002). IFFF and MALDI-TOF can be coupled to analyze polydisperse samples and polymer mixtures (Kassalainen and Williams, 2003). 

Electron beam irradiation is an alternate method to prepare poly(aniline) (PANI) nanocomposite stable at ambient conditions. Ramaprasad et al. [89] synthesized the chitin-polyaniline nanocomposite by electron beam irradiation method (Fig. 3.15). The blends of chitin and PANI with PANI 30, 50, and 70 % (30P, 50P, and 70P) were prepared by mixing 0.5 % (wt%) chitin solution and 0.5 % (wt%) EB solution in DMA with 5 % LiCl in required proportions and irradiated with... 

Two impoilant variants of the method have appeared during the last 2 decades. Both variants are based on confining the volume in which the primary X-ray beam interacts with the analyzed material. In total reflection XRF (TXRF), by irradiating a flat sample with a neargrazing X-ray beam below the angle of total reflection, the in-depth penetration of the primary X-rays can be confined to a few tens of a nanometer below the surface allowing very sensitive surface analysis. Alternatively, the method can be exploited for bulk elemental trace analysis of liquids when these are brought on a clean inert surface (Wobrauschek 2007). 

Alternative physical methods for decontamination including electrostatic precipitation, ultraviolet irradiation, heat, etc., are reviewed below. 

A major handicap of chemical crosslinking agents is the potential toxic effect of residual molecules and/or compounds formed during in-vivo degradation. Therefore, alternative physical methods are pursued, including dry heat, exposure to ultraviolet or y-irradiation [55],... 

Figure 9.1 Characteristics of PIPAAm and conventional TRCS, which is PIPAAm-grafted TCPS prepared hy the electron beam irradiation (EB) irradiation method. TRCS shows cell adhesion and detachment (deadhesion) becanse of the reversible temperature-indnced hydrophilic and hydrophobic alternation. Detached cells contain an ECM component at the basal site of the cell. Cell adhesion and detachment process involves in metabohc adenosine triphosphate (ATP) consumption in the cell.

Alternative modification methods for sol-gel coatings of silica, titania and silica titania using ultraviolet irradiation and water vapor. Thin Solid Films, 351 (12), 91-94. 

Since alternative methods to animal testing should be used for cosmetics, according to the guidelines and/or rules set out in the legislation of most countries (see Section 1.1), to develop in vitro methods for efficacy studies constitutes an authentic challenge. Moreover, invasive in vivo techniques using human volunteers (such as the sun protection factor estimation by UV irradiation methods that was commented in Section 3.1) should also be changed for non-invasive ex vivo techniques or for in vitro methods. 

Alternative approaches to nitric oxide formation include irradiation of air in a nuclear reactor (72) and the oxidation of ammonia to nitric oxide in a fuel cell generating energy (73). Both methods indicate some potential for commercial appHcation but require further study and development. 

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