Structure of oak wood from the Swedish warship Vasa revealed by X-ray scattering and microtomography

Holzforschung ◽  
2012 ◽  
Vol 66 (3) ◽  
Author(s):  
Kirsi Svedström ◽  
Ingela Bjurhager ◽  
Aki Kallonen ◽  
Marko Peura ◽  
Ritva Serimaa
Keyword(s):  
Cellular Structure ◽  
Short Range ◽  
Average Length ◽  
Cellulose Microfibrils ◽  
Crystalline Cellulose ◽  
Oak Wood ◽  
X Ray ◽  
X Ray Scattering ◽  
The Mean ◽  
Ray Scattering

Abstract The degradation of oak wood of the historical warship Vasa was studied, focusing on cellular structure by X-ray microtomography (μCT) and on the nanostructure of the cell wall by wide- and small-angle X-ray scattering (WAXS, SAXS). Solid samples [polyethylene glycol (PEG)-, impregnated and PEG-extracted] were submitted to X-ray analysis and the results compared to those of recent oak. The cellular structure of the Vasa oak was surprisingly well preserved at the micrometer level, according to the μCT images. As revealed by WAXS, the fraction of crystalline cellulose was lower in the Vasa samples compared with recent oak, but the average length and width of cellulose crystallites (25±2 nm and 3.0±0.1 nm, respectively), and the mean microfibril angles (4–9°), showed no significant differences. Accordingly, the crystalline parts of cellulose microfibrils are well preserved in the Vasa oak. The SAXS results indicated a declined short-range order between the cellulose microfibrils and a higher porosity of the Vasa oak compared with recent oak, which may be explained by modification of the hemicellulose-lignin matrix.

A Small-Angle X-Ray Scattering Study on Pre-Irradiated Malate Synthase. The Influence of Formate, Superoxide Dismutase, and Catalase on the X-Ray Induced Aggregation of the Enzyme

1985 ◽  
Vol 40 (5-6) ◽  
pp. 364-372 ◽  
Author(s):  
P. Zipper ◽  
R. Wilfing ◽  
M. Kriechbaum ◽  
H. Durchschlag
Keyword(s):  
Aqueous Solution ◽  
Superoxide Dismutase ◽  
Small Angle ◽  
Malate Synthase ◽  
X Ray ◽  
X Ray Scattering ◽  
X Irradiation ◽  
The Mean ◽  
Induced Aggregation ◽  
Ray Scattering

Abstract The sulfhydryl enzyme malate synthase from baker’s yeast was X-irradiated with 6 kGy in air-saturated aqueous solution (enzyme concentration: ≃ 10 mg/ml; volume: 120 μl), in the absence or presence of the specific scavengers formate, superoxide dismutase, and catalase. After X-irradiation, a small aliquot of the irradiated solutions was tested for enzymic activity while the main portion was investigated by means of small-angle X-ray scattering. Additionally, an unir­radiated sample without additives was investigated as a reference. Experiments yielded the fol­lowing results: 1. X-irradiation in the absence of the mentioned scavengers caused considerable aggregation, fragmentation, and inactivation of the enzyme. The dose Dt37 for total (= repairable + non­-repayable) inactivation resulted as 4.4 kGy. The mean radius of gyration was found to be about 13 nm. The mean degree of aggregation was obtained as 5.7, without correction for fragmenta­tion. An estimation based on the thickness factor revealed that about 19% of material might be strongly fragmented. When this amount of fragments was accordingly taken into account, a value of 7.1 was obtained as an upper limit for the mean degree of aggregation. The observed retention of the thickness factor and the finding of two different cross-section factors are in full accord with the two-dimensional aggregation model established previously (Zipper and Durchschlag, Radiat. Environ. Biophys. 18, 99 - 121 (1980)). 2. The presence of catalytic amounts of superoxide dismutase and/or catalase, in the absence of formate, during X-irradiation reduced both aggregation and inactivation significantly. 3. The presence of formate (10 or 100 mᴍ) during X-irradiation led to a strong decrease of aggregation and inactivation. This effect was more pronounced with the higher formate concen­tration or when superoxide dismutase and/or catalase were simultaneously present during X-irradiation. The presence of formate also reduced the amount of fragments significantly. 4. The results clearly show that the aggregation and inactivation of malate synthase upon X-irradiation in aqueous solution are mainly caused by OH·; to a minor extent O·̄2 and H2O2 are additionally involved in the damaging processes.

Local Atomic Structures in Amorphous and Quasicrystalline Zr70Ni10Pt20and Zr80Pt20Alloys by the Anomalous X-ray Scattering Method

2000 ◽  
Vol 644 ◽  
Author(s):  
Eiichiro Matsubara ◽  
Takahiro Nakamura ◽  
Masaki Sakurai ◽  
Muneyuki Imafuku ◽  
Shigeo Sato ◽  
...  
Keyword(s):  
Short Range ◽  
Short Range Order ◽  
Nearest Neighbor ◽  
Scattering Method ◽  
X Ray ◽  
Coordination Numbers ◽  
Atomic Structures ◽  
X Ray Scattering ◽  
Icosahedral Clusters ◽  
Ray Scattering

AbstractLocal atomic structures around Zr and Pt in a quasicrystalline Zr80Pt20alloy, and amorphous and quasicrystalline Zr70Ni10Pt20alloys have been determined by the anomalous x-ray scattering (AXS) method. A distinct prepeak observed in an intensity profile of the amorphous Zr70Ni10Pt20alloy indicates existence of strong chemical short-range order (CSRO) clusters in the amorphous phase. Total coordination numbers around Zr and Pt in a nearest neighbor region in both alloys have been evaluated. The values around Pt are almost equal to 12 in the amorphous and quasicrystalline states suggest formation of icosahedral clusters around Pt. Some of crystalline structures formed from the quasicrystalline phases by annealing consist of icosahedral clusters of Zr and Ni atoms, or polyhedral clusters of Zr and Pt atoms similar with icosahedral clusters. The present result appears to support that the phase transformation from the amorphous to the crystal through the quasicrystal is explained by the icosahedral CSRO clusters in the amorphous and quasicrystalline states.

scholarly journals Disorder in pentachloronitrobenzene, C6Cl5NO2: a diffuse scattering study

2007 ◽  
Vol 63 (4) ◽  
pp. 663-673 ◽  
Author(s):  
Lynne H. Thomas ◽  
T. Richard Welberry ◽  
Darren J. Goossens ◽  
Aidan P. Heerdegen ◽  
Matthias J. Gutmann ◽  
...  
Keyword(s):  
Diffuse Scattering ◽  
Short Range ◽  
Scattering Data ◽  
X Ray ◽  
Monte Carlo Computer Simulation ◽  
X Ray Scattering ◽  
Scattering Study ◽  
The Mean ◽  
Diffraction Patterns ◽  
Local Relaxation

Monte Carlo computer simulation has been used to interpret and model observed single-crystal diffuse X-ray scattering data for pentachloronitrobenzene, C6Cl5NO2. Each site in the crystal contains a molecule in one of six different basic orientations with equal probability. However, no short-range order amongst these different orientations has been detected. The strong, detailed and very distinctive diffraction patterns can be accounted for almost entirely on the assumption of random occupancy of each molecular site, but with very large local relaxation displacements that tend to increase the neighbouring distances for contacts involving NO2...NO2 and NO2...Cl with a corresponding reduction for those involving Cl...Cl. The results show that the mean NO2...NO2 distance is increased by ∼ 0.6 Å, compared with that given by the average structure determination.

Short range order in liquid acetic acid as studied by X-ray scattering and DFT calculations

2012 ◽  
Vol 173 ◽  
pp. 164-171 ◽  
Author(s):  
Nourhane Ben Zineb ◽  
Abir Chebaane ◽  
Ferid Hammami ◽  
Mohamed Bahri ◽  
Salah Nasr
Keyword(s):  
Acetic Acid ◽  
Dft Calculations ◽  
Short Range ◽  
Short Range Order ◽  
Range Order ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

Anomalous-X-ray scattering associated with short-range order in an Al70Ni15Co15 decagonal quasicrystal

2000 ◽  
Vol 294-296 ◽  
pp. 299-302 ◽  
Author(s):  
Hiroshi Abe ◽  
Nobumichi Tamura ◽  
D Le Bolloc’h ◽  
Simon C Moss ◽  
Yoshie Matsuo ◽  
...  
Keyword(s):  
Short Range ◽  
Short Range Order ◽  
Range Order ◽  
Decagonal Quasicrystal ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

Hydration effects on spacing of primary-wall cellulose microfibrils: a small angle X-ray scattering study

Cellulose ◽  
2007 ◽  
Vol 14 (5) ◽  
pp. 401-408 ◽  
Author(s):  
Craig J. Kennedy ◽  
Adriana Šturcová ◽  
Michael C. Jarvis ◽  
Timothy J. Wess
Keyword(s):  
Small Angle ◽  
Cellulose Microfibrils ◽  
Primary Wall ◽  
X Ray ◽  
X Ray Scattering ◽  
Scattering Study ◽  
Ray Scattering

Detection of short range order in SiO2 thin-films by grazing-incidence wide and small-angle X-ray scattering

2016 ◽  
Vol 119 (15) ◽  
pp. 154103
Author(s):  
Kohki Nagata ◽  
Atsushi Ogura ◽  
Ichiro Hirosawa ◽  
Tomoyuki Suwa ◽  
Akinobu Teramoto ◽  
...  
Keyword(s):  
Thin Films ◽  
Small Angle ◽  
Short Range ◽  
Short Range Order ◽  
Grazing Incidence ◽  
Range Order ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

Short range structure of mechanically alloyed amorphous Ni2Zr investigated by anomalous X-ray scattering

1992 ◽  
Vol 150 (1-3) ◽  
pp. 386-390 ◽  
Author(s):  
F. Buffa ◽  
A. Corrias ◽  
G. Licheri ◽  
G. Navarra ◽  
D. Raoux
Keyword(s):  
Short Range ◽  
Mechanically Alloyed ◽  
X Ray ◽  
X Ray Scattering ◽  
Short Range Structure ◽  
Ray Scattering
Sign in / Sign up

Export Citation Format

Share Document