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Powder X-ray diffraction of capecitabine, C[subscript 15]Hsubscript 22]FNsubscript 3]Osubscript 6] CORRIGENDUM
Abstract not provided
Powder X-ray diffraction of flucytosine, C[subscript 4]H[subscript 4]FN[subscript 3]O
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Powder X-ray diffraction of trimethoprim Form I, C[subscript 14]H[subscript 18]N[subscript 4]O[subscript 3]
Abstract not provided
Powder X-ray diffraction of oseltamivir phosphate (Tamiflu®), C[subscript 16]H[subscript 31]N[subscript 2]O[subscript 8]P
Abstract not provided
Powder X-ray diffraction of azelastine hydrochloride, C[subscript 22]H[subscript 25]ClN[subscript 3]
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Powder X-ray diffraction of pazopanib hydrochloride Form 1, C[subscript 21]H[subscript 24]N[subscrip
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Powder X-ray diffraction of varenicline hydrogen tartrate Form B (Chantix?), (C[subscript 13]H[subsc
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Powder X-ray diffraction of daclatasvir dihydrochloride Form N-2 (Daklinza?), C[subscript 40]H[subsc
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Understanding Powder X-ray Diffraction Profiles from Layered Minerals: The Case of Kaolinite Nanocrystals
Abstract not provided
Unlocking the secrets of porous silicon formation: insights into magnesiothermic reduction mechanism using in situ powder X-ray diffraction studies
The magnesiothermic reduction is an important reaction as it is a bulk method that produces porous Si for a wide range of applications directly from SiO 2 .
Nonicosahedral boron allotrope synthesized at high pressure and high temperature
Theoretical predictions of pressure-induced phase transformations often become long-standing enigmas because of limitations of contemporary available experimental possibilities. Hitherto the existence of a nonicosahedral boron allotrope has been one of them. Here we report on a nonicosahedral boron allotrope, which we denoted as ζ -B, with the orthorhombic α-Ga-type structure (space group Cmce) synthesized in a diamond-anvil cell at extreme high-pressure high-temperature conditions (115 GPa and 2100 K). The structure of ζ -B was solved using single-crystal synchrotron x-ray diffraction and its compressional behavior was studied in the range of very high pressures (115–135 GPa). Here,experimental validation of theoretical predictions reveals the degree of our up-to-date comprehension of condensed matter and promotes further development of solid-state physics and chemistry.
Octupolar versus Néel Order in Cubic 5d 2 Double Perovskites
We report time-of-flight neutron spectroscopy and neutron and x-ray diffraction studies of the 5 d 2 double perovskite magnets, Ba 2 M OsO 6 ( M = Zn , Mg , Ca ). We find that these materials host antiferromagnetically coupled 5 d 2 Os 6 + ions decorating a face-centered cubic (fcc) lattice and are found to remain cubic down to the lowest temperatures. They all exhibit thermodynamic anomalies consistent with a single phase transition at a temperature T * , and a gapped magnetic excitation spectrum with spectral weight concentrated at wave vectors typical of type-I antiferromagnetic orders. However, while muon spin resonance experiments show clear evidence for time-reversal symmetry breaking below T * , we observe no corresponding magnetic Bragg scattering signal. These results are shown to be consistent with ferro-octupolar symmetry breaking below T * , and are discussed in the context of other 5 d double perovskite magnets and theories of exotic orders driven by multipolar interactions.
Nucleation of Dislocations in 3.9 nm Nanocrystals at High Pressure
As circuitry approaches single nanometer length scales, it has become important to predict the stability of single nanometer-sized metals. The behavior of metals at larger scales can be predicted based on the behavior of dislocations, but it is unclear if dislocations can form and be sustained at single nanometer dimensions. Here, we report the formation of dislocations within individual 3.9 nm Au nanocrystals under nonhydrostatic pressure in a diamond anvil cell. We used a combination of x-ray diffraction, optical absorbance spectroscopy, and molecular dynamics simulation to characterize the defects that are formed, which were found to be surface-nucleated partial dislocations. These results indicate that dislocations are still active at single nanometer length scales and can lead to permanent plasticity.
Crystal plasticity finite element simulation of lattice rotation and x-ray diffraction during laser shock compression of tantalum
Here we present a crystal plasticity model tailored for high-pressure, high-strain-rate conditions that uses a multiscale treatment of dislocation-based slip kinetics. We use this model to analyze the pronounced plasticity-induced lattice rotations observed in shock-compressed polycrystalline tantalum via in situ x-ray diffraction. By making direct comparisons between experimentally measured and simulated texture evolution, we can explain how the details of the underlying slip kinetics control the degree of lattice rotation that ensues. Specifically, we show that only the highly nonlinear kinetics caused by dislocation nucleation can explain the magnitude of the rotation observed under shock compression. We demonstrate a good fit between our crystal plasticity model and x-ray diffraction data and exploit the data to quantify the dislocation nucleation rates that are otherwise poorly constrained by experiment in the dynamic compression regime.