Controlled relative humidity in crawl spaces: a new treatment methodology

The harm of salt expansion of saline soil in arid areas has always been a major problem to be solved urgently. According to the conversion rule between sodium sulfate and sodium sulfate decahydrate, sodium sulfate decahydrate crystals can be precipitated from sodium sulfate solution by cooling. Besides, when the relative humidity (RH) exceeds the critical relative humidity (CRH), sodium sulfate decahydrate can be formed by the combination of sodium sulfate and vaporous water, resulting in the salt volume expansion. However, at present, in the salt expansion mechanism of sulfate saline soil, only the influence of liquid water is considered while vaporous water is not involved. To study the effects of temperature, salinity, and ARH on salt expansion, the salt expansion test of dry sulfate saline soil under the action of vaporous water was conducted, and its composition was analyzed by X-ray diffraction (XRD) technology. Experimental results showed that sodium sulfate decahydrate crystals were produced in the sulfate saline soil if the relative humidity (RH) of pore gas exceeded the critical one so that salt expansion occurred. Salt expansion and salt expansion rate of sulfate saline soil increased with the increase of RH and salinity but decreased with the increase of temperature. Therefore, the new salt expansion mechanism of sulfate saline soil under vaporous water is verified. The experimental results further perfected the original salt expansion mechanism of sulfate saline soil under the action of liquid water and guided the study of new treatment methods of sulfate saline soil.

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Management of thoracic aortic lesions - the future is endovascular

VASA ◽

10.1024/0301-1526/a000183 ◽

2012 ◽

Vol 41 (3) ◽

pp. 163-176 ◽

Cited By ~ 6

Author(s):

Weidenhagen ◽

Bombien ◽

Meimarakis ◽

Geisler ◽

A. Koeppel

Keyword(s):

Thoracic Aorta ◽

Clinical Decision Making ◽

Treatment Options ◽

Clinical Decision ◽

Clinical Results ◽

Treatment Modalities ◽

Traumatic Rupture ◽

Descending Thoracic Aorta ◽

New Treatment ◽

Aneurysm Dissection

Open surgical repair of lesions of the descending thoracic aorta, such as aneurysm, dissection and traumatic rupture, has been the state-of-the-art treatment for many decades. However, in specialized cardiovascular centers, thoracic endovascular aortic repair and hybrid aortic procedures have been implemented as novel treatment options. The current clinical results show that these procedures can be performed with low morbidity and mortality rates. However, due to a lack of randomized trials, the level of reliability of these new treatment modalities remains a matter of discussion. Clinical decision-making is generally based on the experience of the vascular center as well as on individual factors, such as life expectancy, comorbidity, aneurysm aetiology, aortic diameter and morphology. This article will review and discuss recent publications of open surgical, hybrid thoracic aortic (in case of aortic arch involvement) and endovascular repair in complex pathologies of the descending thoracic aorta.

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