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Nowadays, there is a very high importance of composite research and variety of their applications in the modern world. In that sense, we researched hollow glass capillaries filled with dissolved Grubbs catalyst (GC) and dicyclopentadiene (DCPD) were incorporated into a fiber-reinforced epoxy with the aim of improving the flow of healing agents to the crack site. The morphological investigation of the crack site was performed using field emission scanning electron microscopy (FESEM), showing the difference between the samples depending on the used solvent. The software analysis of sample photographs has been performed by calculating the fractured/healed surface area of the samples, revealing that approximately 20% of the volume was affected by the impact. Fourier transform infrared spectroscopy (FTIR) revealed that poly (dicyclopentadiene) (PDCPD) formed at the healed interface. However, the FTIR investigation of catalyst stability in different solvents showed structural changes in GC and partial deactivation. The mechanical tests of the samples showed that a recovery of 60% after 24 h at room temperature could be achieved through the use of a solvent and very low concentration of GC. The performed research results are a good base to develop the model for predicting the processes and morphology, with the goal to design the final mechanical and in the future, thermal, properties in advance. This opens a new direction for future research in the field of composite healing. © 2020 Elsevier B.V.

Nowadays, there is a very high importance of composite research and variety of their applications in the modern world. In that sense, we researched hollow glass capillaries filled with dissolved Grubbs catalyst (GC) and dicyclopentadiene (DCPD) were incorporated into a fiber-reinforced epoxy with the aim of improving the flow of healing agents to the crack site. The morphological investigation of the crack site was performed using field emission scanning electron microscopy (FESEM), showing the difference between the samples depending on the used solvent. The software analysis of sample photographs has been performed by calculating the fractured/healed surface area of the samples, revealing that approximately 20% of the volume was affected by the impact. Fourier transform infrared spectroscopy (FTIR) revealed that poly (dicyclopentadiene) (PDCPD) formed at the healed interface. However, the FTIR investigation of catalyst stability in different solvents showed structural changes in GC and partial deactivation. The mechanical tests of the samples showed that a recovery of 60% after 24 h at room temperature could be achieved through the use of a solvent and very low concentration of GC. The performed research results are a good base to develop the model for predicting the processes and morphology, with the goal to design the final mechanical and in the future, thermal, properties in advance. This opens a new direction for future research in the field of composite healing.

Nowadays, there is a very high importance of composite research and variety of their applications in the modern world. In that sense, we researched hollow glass capillaries filled with dissolved Grubbs catalyst (GC) and dicyclopentadiene (DCPD) were incorporated into a fiber-reinforced epoxy with the aim of improving the flow of healing agents to the crack site. The morphological investigation of the crack site was performed using field emission scanning electron microscopy (FESEM), showing the difference between the samples depending on the used solvent. The software analysis of sample photographs has been performed by calculating the fractured/ healed surface area of the samples, revealing that approximately 20% of the volume was affected by the impact. Fourier transform infrared spectroscopy (FTIR) revealed that poly (dicyclopentadiene) (PDCPD) formed at the healed interface. However, the FTIR investigation of catalyst stability in different solvents showed structural changes in GC and partial deactivation. The mechanical tests of the samples showed that a recovery of 60% after 24 h at room temperature could be achieved through the use of a solvent and very low concentration of GC. The performed research results are a good base to develop the model for predicting the processes and morphology, with the goal to design the final mechanical and in the future, thermal, properties in advance. This opens a new direction for future research in the field of composite healing.

Nowadays, there is a very high importance of composite research and variety of their applications in the modern world. In that sense, we researched hollow glass capillaries filled with dissolved Grubbs catalyst (GC) and dicyclopentadiene (DCPD) were incorporated into a fiber-reinforced epoxy with the aim of improving the flow of healing agents to the crack site. The morphological investigation of the crack site was performed using field emission scanning electron microscopy (FESEM), showing the difference between the samples depending on the used solvent. The software analysis of sample photographs has been performed by calculating the fractured/ healed surface area of the samples, revealing that approximately 20% of the volume was affected by the impact. Fourier transform infrared spectroscopy (FTIR) revealed that poly (dicyclopentadiene) (PDCPD) formed at the healed interface. However, the FTIR investigation of catalyst stability in different solvents showed structural changes in GC and partial deactivation. The mechanical tests of the samples showed that a recovery of 60% after 24 h at room temperature could be achieved through the use of a solvent and very low concentration of GC. The performed research results are a good base to develop the model for predicting the processes and morphology, with the goal to design the final mechanical and in the future, thermal, properties in advance. This opens a new direction for future research in the field of composite healing.

Nowadays, there is a very high importance of composite research and variety of their applications in the modern world. In that sense, we researched hollow glass capillaries filled with dissolved Grubbs catalyst (GC) and dicyclopentadiene (DCPD) were incorporated into a fiber-reinforced epoxy with the aim of improving the flow of healing agents to the crack site. The morphological investigation of the crack site was performed using field emission scanning electron microscopy (FESEM), showing the difference between the samples depending on the used solvent. The software analysis of sample photographs has been performed by calculating the fractured/ healed surface area of the samples, revealing that approximately 20% of the volume was affected by the impact. Fourier transform infrared spectroscopy (FTIR) revealed that poly (dicyclopentadiene) (PDCPD) formed at the healed interface. However, the FTIR investigation of catalyst stability in different solvents showed structural changes in GC and partial deactivation. The mechanical tests of the samples showed that a recovery of 60% after 24 h at room temperature could be achieved through the use of a solvent and very low concentration of GC. The performed research results are a good base to develop the model for predicting the processes and morphology, with the goal to design the final mechanical and in the future, thermal, properties in advance. This opens a new direction for future research in the field of composite healing.

Nowadays, there is a very high importance of composite research and variety of their applications in the modern world. In that sense, we researched hollow glass capillaries filled with dissolved Grubbs catalyst (GC) and dicyclopentadiene (DCPD) were incorporated into a fiber-reinforced epoxy with the aim of improving the flow of healing agents to the crack site. The morphological investigation of the crack site was performed using field emission scanning electron microscopy (FESEM), showing the difference between the samples depending on the used solvent. The software analysis of sample photographs has been performed by calculating the fractured/healed surface area of the samples, revealing that approximately 20% of the volume was affected by the impact. Fourier transform infrared spectroscopy (FTIR) revealed that poly (dicyclopentadiene) (PDCPD) formed at the healed interface. However, the FTIR investigation of catalyst stability in different solvents showed structural changes in GC and partial deactivation. The mechanical tests of the samples showed that a recovery of 60% after 24 h at room temperature could be achieved through the use of a solvent and very low concentration of GC. The performed research results are a good base to develop the model for predicting the processes and morphology, with the goal to design the final mechanical and in the future, thermal, properties in advance. This opens a new direction for future research in the field of composite healing. © 2020 Elsevier B.V.

Nowadays, there is a very high importance of composite research and variety of their applications in the modern world. In that sense, we researched hollow glass capillaries filled with dissolved Grubbs catalyst (GC) and dicyclopentadiene (DCPD) were incorporated into a fiber-reinforced epoxy with the aim of improving the flow of healing agents to the crack site. The morphological investigation of the crack site was performed using field emission scanning electron microscopy (FESEM), showing the difference between the samples depending on the used solvent. The software analysis of sample photographs has been performed by calculating the fractured/healed surface area of the samples, revealing that approximately 20% of the volume was affected by the impact. Fourier transform infrared spectroscopy (FTIR) revealed that poly (dicyclopentadiene) (PDCPD) formed at the healed interface. However, the FTIR investigation of catalyst stability in different solvents showed structural changes in GC and partial deactivation. The mechanical tests of the samples showed that a recovery of 60% after 24 h at room temperature could be achieved through the use of a solvent and very low concentration of GC. The performed research results are a good base to develop the model for predicting the processes and morphology, with the goal to design the final mechanical and in the future, thermal, properties in advance. This opens a new direction for future research in the field of composite healing.

Nowadays, there is a very high importance of composite research and variety of their applications in the modern world. In that sense, we researched hollow glass capillaries filled with dissolved Grubbs catalyst (GC) and dicyclopentadiene (DCPD) were incorporated into a fiber-reinforced epoxy with the aim of improving the flow of healing agents to the crack site. The morphological investigation of the crack site was performed using field emission scanning electron microscopy (FESEM), showing the difference between the samples depending on the used solvent. The software analysis of sample photographs has been performed by calculating the fractured/ healed surface area of the samples, revealing that approximately 20% of the volume was affected by the impact. Fourier transform infrared spectroscopy (FTIR) revealed that poly (dicyclopentadiene) (PDCPD) formed at the healed interface. However, the FTIR investigation of catalyst stability in different solvents showed structural changes in GC and partial deactivation. The mechanical tests of the samples showed that a recovery of 60% after 24 h at room temperature could be achieved through the use of a solvent and very low concentration of GC. The performed research results are a good base to develop the model for predicting the processes and morphology, with the goal to design the final mechanical and in the future, thermal, properties in advance. This opens a new direction for future research in the field of composite healing.

Nowadays, there is a very high importance of composite research and variety of their applications in the modern world. In that sense, we researched hollow glass capillaries filled with dissolved Grubbs catalyst (GC) and dicyclopentadiene (DCPD) were incorporated into a fiber-reinforced epoxy with the aim of improving the flow of healing agents to the crack site. The morphological investigation of the crack site was performed using field emission scanning electron microscopy (FESEM), showing the difference between the samples depending on the used solvent. The software analysis of sample photographs has been performed by calculating the fractured/healed surface area of the samples, revealing that approximately 20% of the volume was affected by the impact. Fourier transform infrared spectroscopy (FTIR) revealed that poly (dicyclopentadiene) (PDCPD) formed at the healed interface. However, the FTIR investigation of catalyst stability in different solvents showed structural changes in GC and partial deactivation. The mechanical tests of the samples showed that a recovery of 60% after 24 h at room temperature could be achieved through the use of a solvent and very low concentration of GC. The performed research results are a good base to develop the model for predicting the processes and morphology, with the goal to design the final mechanical and in the future, thermal, properties in advance. This opens a new direction for future research in the field of composite healing.

NASICON-type conductors based on LiGe2(PO4)3 are very promising lithium-conducting electrolytes for all-solid-state lithium-ion and lithium batteries. Al-doped LiGe2(PO4)3 solid electrolytes possessed higher conductivity (∼10-4 S/cm at room temperature) and stability versus metallic Li. In this paper, we present the structure study of Li1.5Al0.5Ge1.5(PO4)3 compound. Fast lithium-ion conductor Li1.5Al0.5Ge1.5(PO4)3 solid electrolyte have been obtained through glass crystallization at 820 °C during 8 h. Structural positions occupied by atoms have been examined by solid state nuclear magnetic resonance experiments. 6Li, 7Li, 27Al 31P NMR measurements have been performed at room temperature. © Published under licence by IOP Publishing Ltd.

The effect of WO3 on the properties and structure of PbO-B2O3-P2O5-WO3 quaternary system was studied. Glasses containing up to 60 mol% WO3 were prepared and the variation of several physical properties was determined with respect to chemical composition in a broad compositional range. Chemical durability of WO3-containing glasses is very high and their thermal stability as well. Glass transition temperature increases with increasing WO3 content up to 566°C. Glass structure was studied by Raman spectroscopy and 31P and 11B MAS NMR spectroscopy. NMR spectroscopy reveals the formation of B-O-W linkages and also the existence of tetrahedral BO4 units and trigonal units BO3 in the glass structure. With increasing WO3 content in the glasses, the number of starting tetrahedral B(OP)3O units decreases and B-O-P bridges are replaced gradually by B-O-W and B-O-B bridges, while the number of BO3 units increases. Raman spectra of the studied glasses possess a doublet of strong vibrational bands in the range at 800-1000 cm-1, assigned to vibrations of W-O- a W=O bonds in tungstate structural units. In glasses with a higher WO3 content WO6 octahedra form tungstate clusters interconnected by W-O-W bridges as reflected in the Raman spectra.. The formation of strong P-O-W and B-O-W linkages in the studied glasses explains high chemical durability of the glasses and the observed increase in the glass transition temperature., Byl studován vliv WO3 na vlastnosti a strukturu skel systému PbO-B2O3-P2O5-WO3. Byla připravena skla s obsahem až 60 mol.% WO3 a byly stanoveny změny řady fyzikálních vlastností na složení skel v širokém rozsahu složení. Teplota skelné transformace roste s obsahem WO3 až na 566°C. Struktura skel byla studována Ramanovouz spektroskopií and MAS NMR spektroskopií jader 31P a 11B. NMR spectroskopie ukázala na tvorbu vazeb B-O-W a též existenci of tetraedrický celků BO4 trigonálních celků BO3 ve strukturní síti skel. in the glass structure. S růstem obsahu WO3 počet celků B(OP)3O klesá a můstky B-O-P jsou nahrazovány celky B-O-W a B-O-B, přičemž počet celků BO3 roste. Tvorba silných vazeb P-O-W a B-O-W je příčinou vysoké chemické odolnosti skel a růstu teploty skelné treansformace.

Co-crystal screening was applied under the assumption that two molecules having relatively similar chemical structures are likely to form co-crystals with identical coformers, in an attempt to improve co-crystal screening efficiency. Piracetam and Levetiracetam were used as model compounds. Both molecules are racetam compounds and have a relatively similar molecular structure. Eleven co-crystals of Piracetam have been described in the literature using ten different acids. These ten acids were selected as potential coformer candidates for the preparation of Levetiracetam co-crystals. Four co-crystals of Levetiracetam were successfully identified by solvent drop and neat grinding: Levetiracetam-d-tartaric acid 1:1 (LDTA), Levetiracetam-R/S-mandelic acid 1:1 (L(RS)MA), Levetiracetam-S-mandelic acid 1:1 (LSMA), and Levetiracetam-2,4- dihyroxybenzoic acid 1:1 (L2,4DHBA). The overall success rate of 40% shows the usefulness of the presented approach. Structural investigation shows the increased success rate to most likely be due to the proficiency of two similar molecules to share the same driving force for assembling multicomponent systems with similar coformers. © 2011 American Chemical Society.

A new microfluidic sample-preparation system is presented for the structural investigation of proteins using small-angle X-ray scattering (SAXS) at synchrotrons. The system includes hardware and software features for precise fluidic control, sample mixing by diffusion, automated X-ray exposure control, UV absorbance measurements and automated data analysis. As little as 15 l of sample is required to perform a complete analysis cycle, including sample mixing, SAXS measurement, continuous UV absorbance measurements, and cleaning of the channels and X-ray cell with buffer. The complete analysis cycle can be performed in less than 3 min. Bovine serum albumin was used as a model protein to characterize the mixing efficiency and sample consumption of the system. The N2 fragment of an adaptor protein (p120-RasGAP) was used to demonstrate how the device can be used to survey the structural space of a protein by screening a wide set of conditions using high-throughput techniques. © 2011 International Union of Crystallography.

A new microfluidic sample-preparation system is presented for the structural investigation of proteins using small-angle X-ray scattering (SAXS) at synchrotrons. The system includes hardware and software features for precise fluidic control, sample mixing by diffusion, automated X-ray exposure control, UV absorbance measurements and automated data analysis. As little as 15 l of sample is required to perform a complete analysis cycle, including sample mixing, SAXS measurement, continuous UV absorbance measurements, and cleaning of the channels and X-ray cell with buffer. The complete analysis cycle can be performed in less than 3 min. Bovine serum albumin was used as a model protein to characterize the mixing efficiency and sample consumption of the system. The N2 fragment of an adaptor protein (p120-RasGAP) was used to demonstrate how the device can be used to survey the structural space of a protein by screening a wide set of conditions using high-throughput techniques. © 2011 International Union of Crystallography.

Derivatization with 1,2-dimethylimidazole-4-sulfonyl chloride (DMISC) has been successfully used as a tool to differentiate between aromatic and aliphatic O-glucuronides of hydroxypropranolol. The analyses were performed with liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) with both a triple quadrupole and an ion trap instrument. Hydroxylated forms of propranolol can be glucuronidated in aliphatic as well as aromatic positions. These isoforms are not distinguishable by tandem MS alone, as they both initially lose 176 Da, i.e. monodehydrated glucuronic acid, giving back the aglycone. Two in vitro systems were set up for the production of propranolol metabolites. The obtained isomers of 4'-hydroxypropranolol glucuronide were determined to correspond to one aliphatic and one aromatic form, using chemical derivatization with DMISC and LC-MSn. DMISC was shown to react with the secondary amine in the case where the naphtol was occupied by the glucuronyl moiety, resulting in a different fragmentation pattern compared with that of the aliphatic glucuronide, where the naphtol group was accessible to derivatization.

This thesis presents novel approaches for structural investigation of glucuronides using chemical derivatization in combination with liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MSn). Today, LC-ESI-MSn is the dominant technique for quantitative as well as qualitative analyses of metabolites, due to its high sensitivity and selectivity. However, for compounds without an easily ionizable group, e.g., steroids, the sensitivity is limited. In the work presented in this thesis, a derivatization procedure forming a basic oxime significantly increased the detection sensitivity for the altrenogest glucuronide. Furthermore, in structural evaluations of glucuronides, the limitation of LC-MSn becomes evident due to the initial neutral loss of 176 u, i.e. monodehydrated glucuronic acid, which often makes it impossible to elucidate the structures of the conjugates. To solve this problem, the main part of the work described in this thesis was devoted to chemical derivatization as a means of facilitating the determination of the site of conjugation. For the first time, the isomeric estriol glucuronides were evaluated using a combination of three reagents 2-chloro-1-methylpyridinium iodide (CMPI), 1-ethyl-3-(3-dimethyl- aminopropyl)-carbodiimide (EDC), and 2-picolylamine (PA). Interestingly, the derivatization gave a selective fragmentation pattern leading to differentiation of the isomers. Another derivatization reagent, 1,2-dimethylimidazole-4-sulfonyl chloride (DMISC), was also tested for the first time in structural investigations. The isomeric glucuronides of morphine, formoterol, and hydroxypropranolol were evaluated. They can all be conjugated in aliphatic as well as aromatic positions. DMISC was proven to be useful in two ways. Firstly, the morphine and formoterol glucuronides that contained a free phenol could be differentiated from those that were conjugated in the aromatic position based on different reactivity. Secondly, for the aromati

This thesis presents novel approaches for structural investigation of glucuronides using chemical derivatization in combination with liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MSn). Today, LC-ESI-MSn is the dominant technique for quantitative as well as qualitative analyses of metabolites, due to its high sensitivity and selectivity. However, for compounds without an easily ionizable group, e.g., steroids, the sensitivity is limited. In the work presented in this thesis, a derivatization procedure forming a basic oxime significantly increased the detection sensitivity for the altrenogest glucuronide. Furthermore, in structural evaluations of glucuronides, the limitation of LC-MSn becomes evident due to the initial neutral loss of 176 u, i.e. monodehydrated glucuronic acid, which often makes it impossible to elucidate the structures of the conjugates. To solve this problem, the main part of the work described in this thesis was devoted to chemical derivatization as a means of facilitating the determination of the site of conjugation. For the first time, the isomeric estriol glucuronides were evaluated using a combination of three reagents 2-chloro-1-methylpyridinium iodide (CMPI), 1-ethyl-3-(3-dimethyl- aminopropyl)-carbodiimide (EDC), and 2-picolylamine (PA). Interestingly, the derivatization gave a selective fragmentation pattern leading to differentiation of the isomers. Another derivatization reagent, 1,2-dimethylimidazole-4-sulfonyl chloride (DMISC), was also tested for the first time in structural investigations. The isomeric glucuronides of morphine, formoterol, and hydroxypropranolol were evaluated. They can all be conjugated in aliphatic as well as aromatic positions. DMISC was proven to be useful in two ways. Firstly, the morphine and formoterol glucuronides that contained a free phenol could be differentiated from those that were conjugated in the aromatic position based on different reactivity. Secondly, for the aromati

This thesis presents novel approaches for structural investigation of glucuronides using chemical derivatization in combination with liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MSn). Today, LC-ESI-MSn is the dominant technique for quantitative as well as qualitative analyses of metabolites, due to its high sensitivity and selectivity. However, for compounds without an easily ionizable group, e.g., steroids, the sensitivity is limited. In the work presented in this thesis, a derivatization procedure forming a basic oxime significantly increased the detection sensitivity for the altrenogest glucuronide. Furthermore, in structural evaluations of glucuronides, the limitation of LC-MSn becomes evident due to the initial neutral loss of 176 u, i.e. monodehydrated glucuronic acid, which often makes it impossible to elucidate the structures of the conjugates. To solve this problem, the main part of the work described in this thesis was devoted to chemical derivatization as a means of facilitating the determination of the site of conjugation. For the first time, the isomeric estriol glucuronides were evaluated using a combination of three reagents 2-chloro-1-methylpyridinium iodide (CMPI), 1-ethyl-3-(3-dimethyl- aminopropyl)-carbodiimide (EDC), and 2-picolylamine (PA). Interestingly, the derivatization gave a selective fragmentation pattern leading to differentiation of the isomers. Another derivatization reagent, 1,2-dimethylimidazole-4-sulfonyl chloride (DMISC), was also tested for the first time in structural investigations. The isomeric glucuronides of morphine, formoterol, and hydroxypropranolol were evaluated. They can all be conjugated in aliphatic as well as aromatic positions. DMISC was proven to be useful in two ways. Firstly, the morphine and formoterol glucuronides that contained a free phenol could be differentiated from those that were conjugated in the aromatic position based on different reactivity. Secondly, for the aromati

This thesis presents novel approaches for structural investigation of glucuronides using chemical derivatization in combination with liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MSn). Today, LC-ESI-MSn is the dominant technique for quantitative as well as qualitative analyses of metabolites, due to its high sensitivity and selectivity. However, for compounds without an easily ionizable group, e.g., steroids, the sensitivity is limited. In the work presented in this thesis, a derivatization procedure forming a basic oxime significantly increased the detection sensitivity for the altrenogest glucuronide. Furthermore, in structural evaluations of glucuronides, the limitation of LC-MSn becomes evident due to the initial neutral loss of 176 u, i.e. monodehydrated glucuronic acid, which often makes it impossible to elucidate the structures of the conjugates. To solve this problem, the main part of the work described in this thesis was devoted to chemical derivatization as a means of facilitating the determination of the site of conjugation. For the first time, the isomeric estriol glucuronides were evaluated using a combination of three reagents 2-chloro-1-methylpyridinium iodide (CMPI), 1-ethyl-3-(3-dimethyl- aminopropyl)-carbodiimide (EDC), and 2-picolylamine (PA). Interestingly, the derivatization gave a selective fragmentation pattern leading to differentiation of the isomers. Another derivatization reagent, 1,2-dimethylimidazole-4-sulfonyl chloride (DMISC), was also tested for the first time in structural investigations. The isomeric glucuronides of morphine, formoterol, and hydroxypropranolol were evaluated. They can all be conjugated in aliphatic as well as aromatic positions. DMISC was proven to be useful in two ways. Firstly, the morphine and formoterol glucuronides that contained a free phenol could be differentiated from those that were conjugated in the aromatic position based on different reactivity. Secondly, for the aromati