Picosecond Dynamics of Laser Annealing

1981 ◽  
Vol 4 ◽  
Author(s):  
Dae M. Kim ◽  
Rajiv R. Shah ◽  
D. Von Der Linde ◽  
D.L. Crosthwait
Keyword(s):  
Electron Microscopy ◽  
Laser Annealing ◽  
Point Of View ◽  
Plasma Model ◽  
Reflection And Transmission ◽  
Time Resolved ◽  
Low Intensity ◽  
Simultaneous Measurements ◽  
Thermal Melting ◽  
Scanning Electron

ABSTRACTWe report simultaneous measurements of time resolved reflection and transmission of low intensity 1.06 μm, 35 ps pulses subsequent to excitation of 50 KeV, 1016 cm−2 boron implanted silicon by 0.53 μm 35 ps pulses of varying energy densities. The samples are examined by optical and scanning electron microscopy in conjunction with defect etching. These data are discussed from the point of view of both the thermal melting model and plasma model.

Synchrotron X-Ray Study of the Structure of Silicon During Pulsed Laser Processing

1981 ◽  
Vol 4 ◽  
Author(s):  
B. C. Larson ◽  
C. W. White ◽  
T. S. Noggle ◽  
J. F. Barhorst ◽  
D. Mills
Keyword(s):  
Laser Annealing ◽  
Pulsed Laser ◽  
Temperature Profiles ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
Near Surface ◽  
X Ray ◽  
Pulsed Laser Annealing ◽  
Pulsed Laser Processing ◽  
Thermal Melting

ABSTRACTSynchrotron x-ray pulses have been used to make nanosecond resolution time-resolved x-ray diffraction measurements on silicon during pulsed laser annealing. Thermal expansion analysis of near-surface strains during annealing has provided depth dependent temperature profiles indicating >1100°C temperatures and diffraction from boron implanted silicon has shown evidence for near-surface melting. These results are in qualitative agreement with the thermal melting model of laser annealing.

Chloroplast division in spinach leaves examined by scanning electron microscopy and freeze-etching

1980 ◽  
Vol 46 (1) ◽  
pp. 87-96
Author(s):  
N. Chaly ◽  
J.V. Possingham ◽  
W.W. Thomson
Keyword(s):  
Electron Microscopy ◽  
Green Light ◽  
Cell Area ◽  
Low Intensity ◽  
Spinach Leaf ◽  
Freeze Etching ◽  
Leaf Disks ◽  
Scanning Electron ◽  
Spinach Leaves

Spinach leaf disks were cultured for 5 days in low-intensity green light and then were transferred to high-intensity white light. Harvests over the next 16 h established that cell area increased by about 80% and chloroplast number per cell increased by about 65%, while the percentage of dumbbell-shaped chloroplasts per cell decreased by 65%. Freeze-etch replicas of fixed and unfixed leaf disks, as well as scanning electron-microscope preparations of fixed material, contained dumbbell-shaped chloroplasts constricted to various degrees. Freeze-etch replicas of unfixed cells from young leaf bases, in which the number of chloroplasts per cell is known to be rapidly increasing, also contained many constricted chloroplasts. It is concluded that dumbbell-shaped chloroplasts occur in vivo and represent a stage in the division of chloroplasts.

scholarly journals Identification by RAMAN Microscopy of magnesian vivianite formed from Fe2+, Mg, Mn2+and P043-’ in a Roman camp near fort Vechten, Utrecht, The Netherlands

2003 ◽  
Vol 82 (2) ◽  
pp. 209-214 ◽  
Author(s):  
J.T. Kloprogge ◽  
D. Visser ◽  
W.N. Martens ◽  
L.V. Duong ◽  
R.L. frost
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
The Netherlands ◽  
Soil Sample ◽  
Raman Microscopy ◽  
Low Intensity ◽  
Bending Modes ◽  
Scanning Electron

AbstractThe presence of a magnesian vivianite (Fe2+)2.5(Mg,Mn,Ca)0.5(PO4)2·8H2O, has been identified in a soil sample from a Roman camp near Fort Vechten, The Netherlands, using a combination of Raman microscopy and scanning electron microscopy. An unsubstituted vivianite and baricite were characterised for comparative reasons. The split phosphate-stretching mode is recognised around 1115, 1062 and 1015 cm−1, while the corresponding bending modes are found around 591, 519, 471 and 422 cm−1. The substitution of Mg and Mn for Fe2+in the crystal structure causes a shift towards higher wavenumbers compared to pure vivianite. As shown by the baričite sample substitution causes a broadening of the bands. The observed broadening however is larger than can be explained by substitution alone. The low intensity of the water bands, especially in the OH-stretching region between 2700 and 3700 cm−1indicates that the magnesian vivianite is partially dehydrated, which explains the much larger broadening than the observed broadening caused by substitution of Mg and Mn in vivianite and baričite.

Structural and dynamic descriptions of the development of Utricularia foliosa and U. australis

1990 ◽  
Vol 68 (9) ◽  
pp. 1989-2003 ◽  
Author(s):  
Rolf Sattler ◽  
Rolf Rutishauser
Keyword(s):  
Electron Microscopy ◽  
Leaf Development ◽  
Point Of View ◽  
Developmental Morphology ◽  
Dynamic Approach ◽  
Plant Form ◽  
Dynamic Description ◽  
Structural Descriptions ◽  
Process Combination ◽  
Scanning Electron

In this developmental investigation of Utricularia foliosa and U. australis by means of scanning electron microscopy we demonstrate the relativity of morphological facts and descriptions. We provide several descriptions in terms of the structural categories "stem" and '"leaf." These contrasting, if not contradictory, descriptions are complementary to each other, i.e., they present different aspects of the unusual complexity of these species. In addition to these structural descriptions, we provide a dynamic description in terms of process morphology. According to this dynamic approach, each form is seen as a process combination. Structural change during ontogeny and phylogeny is a change in process combinations. From this point of view, the unusual process combinations of the two Utricularia species do not pose a morphological problem, although they cannot be clearly assigned to mutually exclusive categories such as stem and leaf. In addition to the clarification of the developmental morphology of the two Utricularia species, this investigation illustrates process morphology as a general approach to the description and comparison of plant form. The relevance of this approach to other biological disciplines such as cladistics is briefly indicated. Key words: Utricularia, Lentibulariaceae, shoot development, leaf development, morphogenesis, process morphology.

scholarly journals Acoustic Properties of a New Composite Material Obtained from Feather Flour and Recycled Polypropylene

2022 ◽  
Vol 58 (4) ◽  
pp. 84-93
Author(s):  
Mirela Alina Constantin ◽  
Lucian Alexandru Constantin ◽  
Sebastian Aradoaei ◽  
Mihaela Aradoaei ◽  
Mihai Bratu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Natural Fibers ◽  
Adsorption Properties ◽  
Point Of View ◽  
Acoustic Properties ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Recycled Polypropylene ◽  
Sustainable Materials ◽  
Scanning Electron

Sustainable materials made from recycled materials are an alternative to traditional materials (synthetic ones) and present a lower environmental impact. Due to the fact that natural fibers were successfully used to produce environmentally friendly sound adsorbing materials, biocomposites made from recycled polypropylene (PPR), feathers flour (FF) with / without compatibilizers (C) were obtained and characterized from the point of view of their acoustical behavior. Obtained materials were characterized also from the morphological and compositional point of view by scanning electron microscopy and thermal gravimetric analysis. All tested samples presented sound adsorption properties but the best results were obtained for the biocomposites with FF content of 10%-20%.

Properties Affecting the Reactivity of Lime

2021 ◽  
Vol 325 ◽  
pp. 92-97
Author(s):  
Dorothea Sklenářová ◽  
Karel Dvořák ◽  
Dušan Dolák
Keyword(s):  
Electron Microscopy ◽  
Total Porosity ◽  
Point Of View ◽  
Insoluble Residue ◽  
Sem Images ◽  
Geological Age ◽  
Different Temperatures ◽  
Identification Parameter ◽  
Lime Reactivity ◽  
Scanning Electron

Lime reactivity is the most used identification parameter for lime quality. The reaction may vary in its rate and maximum reached temperature. In this study, the influence of the properties of limestone on the course of the reaction is studied. The samples are thoroughly examined from a geological point of view (geological age and origin, genesis and diagenesis) and their physicochemical properties are described (total porosity, limestone category, chemical analysis, insoluble residue). Different temperatures and isothermal loads were selected to study the effect of the burning process on the lime microstructure. The newly formed CaO is observed by scanning electron microscopy (SEM images). Lime reactivity analysis is performed, and different reaction courses are compared.

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