Search results for "SAHA"

Acid-catalyzed mechanocatalytic pretreatment to improve sugar release from birch sawdust : Structural and chemical aspects

2022

This study examined acid-catalyzed mechanocatalytic pretreatment of birch sawdust without a separate impregnation step. Catalyst amount and pretreatment time were the key variables. Pretreated material was mixed with water for hydrolysis (100 °C, 60 min). The efficient release of total reducing sugars from birch sawdust is significant to the path towards biofuels and biochemicals. Based on the results, the structure and surface of birch sawdust changed as a function of mechanocatalytic pretreatment. Milling time caused significant transformations in birch structure and also increased the yields of reducing sugars. The highest yield of total reducing sugar from pretreated sawdust was 23.0% a…

Zymomonas mobilis ekstracelulārās levānsaharāzes aktivitātes dinamiska saharozes fermentācijā un to ietekmējošie apstākļi

2015

Darba mērķis bija izpētīt Z.mobilis ekstracelulārās levānsaharāzes levāna biosintēzes aktivitātes izmaiņas saharozes fermentācijas laikā un izvērtēt fermentācijas apstākļus, pie kuriem iespējams iegūt augstāku šī fermenta aktivitāti fermentācijas vidē. Tika pētīta substrāta koncentrācijas ietekme uz levānsaharāzes aktivitātes līmeņa izmaiņām. Tika novērtēts ekstracelulārās levānsaharāzes sadalījums starp fermentācijas vidi un šūnu virsmu un tā izmaiņas dažādās fermentācijas fāzēs. Darba izpildes laikā tika apgūtas Z.mobilis šūnu kultivēšanas metodes un darbam nepieciešamās analītiskās procedūras. Veikta darba tēmai atbilstošās zinātniskās literatūras meklēšana, studijas un analīze. Darbs ve…

Are non-invasive fibrosis markers for chronic hepatitis B reliable in sub-Saharan Africa?

2017

Background In the absence of liver biopsy, the World Health Organization recommends non-invasive tests, such as aspartate aminotransferase to platelet ratio index and FIB-4, to assess liver fibrosis in patients with chronic hepatitis B. However, these tests are not well validated in sub-Saharan Africa. Recently, a new marker, gamma-glutamyl transpeptidase to platelet ratio, was found to be more accurate in an African setting, but this needs confirmation in other cohorts. Methods A treatment program for chronic hepatitis B was initiated in Addis Ababa, Ethiopia, in 2015. Non-invasive tests were compared with transient elastography (Fibroscan 402, Echosense, France) using the following thresh…

Kun toimeen tartutaan : tukin tie lautatavaraksi - metsästä maailmalle : Oy Mikko Kaloisen puutavaraliikkeen historia

2015

Kosket kylän keskellä : tutkimus muistamisesta, kyläyhteisöstä ja vesivoimasta Kuhmoisten Pihlajakoskella

2010

Selective hemicellulose hydrolysis of Scots pine sawdust

2019

The depletion of fossil resources is driving forward the search for new and alternative renewable feedstocks in the production of renewable chemicals, which could replace the petroleum-based ones. One such feedstock is pine (Pinus sylvestris) sawdust, which is generated enormous amounts in Finnish sawmills yearly. However, prior to the utilization in high-value applications, it needs to be fractionated into its constituents. In this work, the objective was to produce monomeric hemicellulose sugars from pine sawdust without degrading cellulose or lignin simultaneously. The influence of the reaction temperature and time, as well as acid type and concentration, was studied. Based on the result…

Tikkakosken saha

1891

Complessità antropologica della nozione di confine

2004

The work pays specific attention to themes such as the desert, the limes, fortifications, populations, nomadism, peaceful or conflictual interaction between man and landscape along the borders, cultural identities, and the Roman Empire's exchanges with peoples located beyond the Sahara limes

Solar radiative effects of a Saharan dust plume observed during SAMUM assuming spheroidal model particles

2011

The solar optical properties of Saharan mineral dust observed during the Saharan Mineral Dust Experiment (SAMUM) were explored based on measured size-number distributions and chemical composition. The size-resolved complex refractive index of the dust was derived with real parts of 1.51–1.55 and imaginary parts of 0.0008–0.006 at 550 nm wavelength. At this spectral range a single scattering albedo ω o and an asymmetry parameter g of about 0.8 were derived. These values were largely determined by the presence of coarse particles. Backscatter coefficients and lidar ratios calculated with Mie theory (spherical particles) were not found to be in agreement with independently measured lidar data.…

Perheyrittäjyyden arjen kulttuuri : kolmen sukupolven sahatoimintaa

2005

This study focuses on the entrepreneurial longevity of a family business by observing an old sawmill. The activities within the firm are influenced by the change in the Finnish Society during the 20th century and the decline of the village community. The challenge for surviving at the periphery and maintaining operations in a single family over generations is cultural knowledge. Ethnographic approach through thick descriptions provides a chance to follow the change in everyday customs and interpret its meanings, and these are evaluated using critical methodology. The interdisciplinary theoretical foundation and approach combines the disciplines of economy and anthropology. The family busine…