Evaluation of Analysis Methods for Formaldehyde, Acetaldehyde, and Furfural from Fast Pyrolysis Bio-oil

Fast pyrolysis bio-oil (FPBO), a second-generation liquid bioenergy carrier, is currently entering the market. FPBO is produced from biomass through the fast pyrolysis process and contains a large number of constituents, of which a significant part is still unknown. Various analytical methods have been systematically developed and validated for FPBO in the past; however, reliable methods for characterization of acetaldehyde, formaldehyde, and furfural are still lacking. In this work, different analysis methods with (HS-GC/ECD, HPLC, UV/Vis) and without derivatization (GC/MSD, HPLC) for the characterization of these components were evaluated. Five FPBO samples were used, covering a range of biomass materials (pine wood, miscanthus, and bark), storage conditions (freezer and room temperature), and after treatments (none, filtration, and vacuum evaporation). There was no difference among the methods for the acetaldehyde analysis. A significant difference among the methods for the determination of formaldehyde and furfural was observed. Thus, more data on the accuracy of the methods are required. The precision of all methods was below 10% with the exception of the HPLC analysis of acetaldehyde with an RSD of 14%. The concentration of acetaldehyde in the FPBO produced from the three different biomasses and stored in a freezer after production ranged from 0.24 to 0.60 wt %. Storage at room temperature and vacuum evaporation both decreased significantly the acetaldehyde concentration. Furfural concentrations ranged from 0.11 to 0.36 wt % for the five samples. Storage and after treatment affected the furfural concentration but to a lesser extent than for acetaldehyde. Storage at room temperature decreased formaldehyde similarly to acetaldehyde; however, after vacuum-evaporation the concentration of formaldehyde did not change. Thus, the analysis results indicated that in FPBO the equilibrium of formaldehyde and methylene glycol is almost completely on the methylene glycol side, as in aqueous solutions. All three methods employed here actually measure the sum of free formaldehyde and methylene glycol (FAMG)

Hydrotreatment of the carbohydrate-rich fraction of pyrolysis liquids using bimetallic Ni based catalyst:Catalyst activity and product property relations

The use of novel nickel based catalysts for the catalytic hydrotreatment of pyrolytic sugars, the carbohydrate rich fraction of pine derived pyrolysis liquids, is reported. The catalysts are characterized by a high nickel loading (38 to 57 wt%), promoted by Cu, Pd, and/or Mo and a SiO2 based inorganic matrix. Experiments were carried out at 180 degrees C and 120 bar initial hydrogen pressure (room temperature) in a batch reactor set-up to gain insight in catalyst activity and product properties as a function of the catalyst composition. The most promising catalyst in terms of activity, as measured by the hydrogen uptake during reaction, was the Ni-Mo/SiO2-Al2O3 catalyst whereas the performance of the monometallic Ni/SiO2-Al2O3 catalyst was the lowest. As a result, the product oil obtained by the bimetallic Ni-Mo catalyst showed the highest H/C ratio and the lowest molecular weight of all catalysts tested. A detailed catalyst characterization study revealed that addition of Mo to the Ni catalyst suppresses the agglomeration of nickel nanoparticles during the catalytic hydrotreatment reaction

Optimization Studies on the Hydro-acylation of 1-Alkenes to α-Methylketones using a Homogeneous Palladium/Josiphos Catalyst

The effect of process conditions (temperature, partial pressures of CO and H2) on the product selectivity and ee of the palladium-catalysed asymmetric hydro-acylation of 1-pentene in dichloromethane with the chiral Josiphos ligand (SL-J008-1, L1) was investigated. The highest ee value (73%) for the desired product 4-methyl-5-decanone (1) was obtained at the lowest temperature in the range (30 °C). The selectivity for 1 was between 12 and 20 mol % at 30 °C, though considerably higher at 90 °C (59 mol %). Statistical modeling was applied to quantify the influence of the process conditions on the product selectivity and ee.

FÖRSTELÄRARES MENINGSSKAPANDE I SITT UPPDRAG En fallstudie om att leda kollegialt lärande

Syfte: Syftet med studien är att utveckla kunskap om förstelärares förståelse av sitt uppdrag som ledare för kollegialt lärande genom att belysa hur förstelärare tolkar begreppet kollegialt lärande, hur förstelärare skapar mening i sitt uppdrag samt hur förstelärare bidrar till meningsskapande i kollegiala lärprocesser. Teori: Ett hermeneutiskt vetenskapsfilosofiskt perspektiv utgör teoretisk ansats för studien. Forskningsansatsen har varit abduktiv. Som teoretiskt ramverk för analys av data används Weicks teorier om meningsskapande inklusive begreppet förändringspoet (change poet). Simon och Ruijters kategorisering av individuellt och kollektivt lärande används också som analysverktyg. Metod: Studien har en kvalitativ forskningsdesign. Fallstudie används som forskningsstrategi. Semistrukturerade intervjuer används för insamling av empiri. Resultat: Studien visar hur olika tolkningar av begreppet kollegialt lärande påverkar förstelärares meningsskapande om hur kollegialt lärande kan ledas. Det visar också att kollegialt lärande främst tolkas som en process medan ett gemensamt kunskapande inte i så stor utsträckning fokuseras. Studiens resultat berikar även tidigare forskning genom att synliggöra hur förstelärare skapar mening i sitt uppdrag men även hur reduceringar kring roll och uppdrag begränsar bilden av vad en förstelärare skulle kunna vara för något. I studien syns också hur förstelärare i sitt uppdrag tar rollen som förändringspoeter och därmed blir betydelsefulla som meningsskapare i kollegiala lärprocesser tillsammans med kollegor

Standardized porcine unilateral femoral nailing is associated with changes in PMN activation status, rather than aberrant systemic PMN prevalence

PURPOSE Intramedullary nailing (IMN) of fractures is associated with increased rates of inflammatory complications. The pathological mechanism underlying this phenomenon is unclear. However, polymorphonuclear granulocytes (PMNs) seem to play an important role. We hypothesized that a femur fracture and standardized IMN in pigs is associated with altered appearance of PMNs in circulation and enhanced activation status of these cells. METHODS A porcine model including a femur fracture and IMN was utilized. Animals were randomized for control [anesthesia + mechanical ventilation only (A/MV)] and intervention [A/MV and unilateral femur fracture (FF) + IMN] conditions. PMN numbers and responsiveness, integrin (CD11b), L-selectin (CD62L) and Fcγ-receptor (CD16 and CD32)-expression levels were measured by flowcytometry of blood samples. Animals were observed for 72 h. RESULTS Circulatory PMN numbers did not differ between groups. Early PMN-responsiveness was retained after insult. PMN-CD11b expression increased significantly upon insult and peaked after 24 h, whereas CD11b in control animals remained unaltered (P = 0.016). PMN-CD16 expression levels in the FF + IMN-group rose gradually over time and were significantly higher compared with control animals, after 48 h (P = 0.016) and 72 h (P = 0.032). PMN-CD62L and CD32 expression did not differ significantly between conditions. CONCLUSION This study reveals that a femur fracture and subsequent IMN in a controlled setting in pigs is associated with enhanced activation status of circulatory PMNs, preserved PMN-responsiveness and unaltered circulatory PMN-presence. Indicating that monotrauma plus IMN is a specific and substantial stimulus for the cellular immune system. Early alterations of circulatory PMN receptor expression dynamics may be predictive for the intensity of the post traumatic response

Instant intra-operative neutropenia despite the emergence of banded (CD16 dim/CD62L bright) neutrophils in peripheral blood - An observational study during extensive trauma-surgery in pigs

Introduction: Deregulation of polymorphonuclear neutrophils (PMNs) is an essential step in the development of inflammatory complications upon trauma. Different neutrophil subtypes have been identified recently, however, the role of neutrophil subtypes in immunoregulation upon trauma is unclear. We hypothesize that extensive trauma surgery causes instant progressive heterogeneity of the blood neutrophil pool, and increased appearance of young (CD16dim/CD62Lbright) neutrophils in peripheral blood. Material and methods: A standardized extensive thoraco-abdominal porcine trauma surgery model was utilized, and 12 animals were included. Blood was collected at defined timepoints and neutrophil numbers and subtypes were studied by flowcytometry. Neutrophil subtypes were identified by differences in cell surface expression levels of CD16 (FcγRIII) and CD62L (L-selectin). Porcine neutrophil subtypes were further characterized after flow sorting. Results: Eleven animals survived the 3-hour surgical protocol. Neutrophil numbers dropped significantly from a mean of 8,6 ± 3,5 × 106 to 2,4 ± 1,8 × 106 cells/ml during 180 min, (p<0.001). Simultaneously, the blood PMN population became increasingly heterogeneous due to the appearance of new neutrophil subtypes. Cell sorting experiments and cytological analysis revealed that these porcine subtypes had specific morphological characteristics, mimicking their human counterparts. At baseline, 88% ± 1 percent of circulatory PMNs comprised of mature (CD16bright/CD62Lbright) PMNs, while at 3 h the blood PMN pool consisted of 59% ± 2 percent of mature subtypes (p<0.001). Despite a marked drop in neutrophil levels during surgery, absolute and relative numbers of banded (CD16dim/CD62Lbright) neutrophils continued to rise throughout surgery. Conclusion: Standardized extensive trauma surgery was associated with instant progressive neutropenia and increased heterogeneity of the blood neutrophil pool. Furthermore, three different neutrophil subsets in peripheral porcine blood were identified over the course of surgery. Further studies should clarify their precise role in the development of early organ failure upon extensive trauma surgery. This for the first time exemplifies experimentally the time constraints and impact of damage control surgery after severe trauma

Shift of Neutrophils From Blood to Bone Marrow Upon Extensive Experimental Trauma Surgery

Introduction Extensive trauma surgery evokes an immediate cellular immune response including altered circulatory neutrophil numbers. The concurrent bone marrow (BM) response however is currently unclear. We hypothesize that these BM changes include (1) a relative reduction of the bone marrow neutrophil fraction and (2) increasing heterogeneity of the bone marrow neutrophil pool due to (3) the appearance of aged/returning neutrophils from circulation into the BM-compartment. Materials and Methods Eight pigs were included in a standardized extensive trauma surgery model. Blood and bone marrow samples were collected at baseline and after 3 hours of ongoing trauma surgery. Leukocyte and subtype counts and cell surface receptor expression levels were studied by flow cytometry. Results All animals survived the interventions. A significant drop in circulating neutrophil counts from 9.3 to 3.2x10$^{6}$ cells/ml (P=0.001) occurred after intervention, whereas circulatory neutrophil cell surface expression of CD11b increased. The concurrent bone marrow response included an increase of the BM neutrophil fraction from 63 ± 3 to 71 ± 3 percent (P<0.05). Simultaneously, the BM neutrophil pool became increasingly mature with a relative increase of a CXCR4$^{high}$-neutrophil subtype that was virtually absent at baseline. Conclusion The current study shows a shift in composition of the BM neutrophil pool during extensive trauma surgery that was associated with a relatively circulatory neutropenia. More specifically, under these conditions BM neutrophils were more mature than under homeostatic conditions and a CXCR4$^{high}$-neutrophil subset became overrepresented possibly reflecting remigration of aged neutrophils to the BM. These findings may contribute to the development of novel interventions aimed to modify the trauma-induced immune response in the BM