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History of Radiology
Published in Paolo Russo, Handbook of X-ray Imaging, 2017
It was thanks to the work of Portuguese radiologists that the goal of practical angiography in the living was fully realized (Veiga-Pries and Grainger 1982). The leader of this Portuguese team was Egas Moniz, who was the Professor of Neurology in Lisbon. Moniz was physically severely handicapped by topaceous gout and was therefore unable to make any vascular injections himself; however, he meticulously planned his research project on the localization of cerebral tumors. He was dissatisfied with the recently developed technique of ventriculography, which he found could make a correct diagnosis in less than a third of patients. Moniz had been aware of the pioneer work of the Frenchmen Jean Sicard and Jacques Forestier in early angiography. After his initially efforts to opacify the brain failed, he started performing intra-arterial injections. He had surmised that if he could concentrate radiopaque material in the brain then the brain itself would be visible on radiographs, and knowing that bromides were used as sedatives, since they accumulated in the brain they might show up on radiographs. Moniz gave large amounts of bromides orally but showed nothing. He then tried injecting bromide into a carotid artery but apart from giving the patient a headache he again showed nothing. Next he thought of opacifying the brain by intravenous or parenteral administration of a variety of agents, giving large doses of lithium bromide and strontium bromide. After these techniques failed he tried using intra-arterial injections using an iodide salt. Iodine was chosen because its atomic weight is higher than bromine's. After many difficulties, he was successful using a 25% solution of sodium iodide with bilateral carotid artery cut downs. His successful patient, on June 28, 1927, was the ninth in his series, a young man with a pituitary tumor. Moniz (1931) shows the head positioned for angiography (Figure 18.28), and angiogram (Figure 18.29).
An experimental investigation on the performance of designed closed reactor system on the thermochemical heat storage of magnesium chloride hexahydrate
Published in Experimental Heat Transfer, 2023
A.A. Hawwash, Shinsuke Mori, Hamdy Hassan
A closed THS system with a honeycomb heat exchanger was fabricated by Lele et al. [56] to prevent gel-layer formation and agglomeration at the beginning of the bed during the hydration process. They used strontium bromide as an absorbent. While the vapor pressure during the hydration process was 42 mbar, the dehydration temperature was 105°C. Their conclusion explained that the SrBr2.6 H2O cycling stability can be achieved.
Thermal stability evaluation of selected zeolites for sustainable thermochemical energy storage
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021
Ankammarao Padamurthy, Jalaiah Nandanavanam, Parameshwaran Rajagopalan
Calcium hydroxide (Ca(OH)2) was evaluated for 20 cycles on a TCES prototype system and found material’s agglomeration, sintering, drop-in thermal conductivity, and uneven heat release rates (Cao et al. 2018). To address the agglomeration-related issues of SrBr2.6H2O, a honeycomb structure-based TCES prototype was developed and run for 13 cycles to find a satisfactory performance (Fopah-Lele et al. 2016). In an attempt to address the pure materials’ limitations such as agglomeration, swelling, sintering, low energy storage density, low thermal conductivity, low stability (Courbon et al. 2017), high dehydration temperature (Henao-Sierra et al. 2018), low sorption capacity (Pino et al. 1996), composite materials were prepared and tested. Cyclability studies on composite materials like magnesium hydroxide-lithium chloride (Mg(OH)2-LiCl) (Ishitobi et al. 2012), calcium carbonate-silicon dioxide (CaCO3-SiO2) (Chen et al. 2018), strontium bromide-silica gel (SrBr2-Silica gel) (Courbon et al. 2017), multivalent metal oxides (Mn2O3-Mn3O4) (Carrillo et al. 2014) were reported. Most of the aforementioned composite materials displayed: (i) an excellent cyclability, (ii) a mild drop in energy storage density due to their reduced reactivity, and (iii) lower dehydration temperatures that permit to use low-temperature heat sources (e.g. solar energy, industrial waste heat). To improve the stability and energy storage capacity of CaCO3, graphite nanosheets were impregnated (Han et al. 2018). Ca(OH)2-SiO2-based composite was tested on a TCES prototype and found good cyclability (Roßkopf et al. 2014). Single-cycle investigations were conducted on silica X zeolites, SAPO-34, aluminophosphates, and composites (CaCl2/attapulgite) for TCES applications and found the best results from the silica X zeolites (Jänchen et al. 2005). Zeolite-NaY, zeolite-HY, zeolite-NaX, and zeolite-MORDENITE were evaluated for a single cycle and found that the first two materials yield high dehydration/hydration enthalpies (Whiting et al. 2014). Most of the cited works here, notably used characterization tools like dynamic vapor sorption (DVS) analyzer, differential thermogravimetric (DTG) analyzer, differential scanning calorimeter (DSC), etc. for cyclability studies.