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• The purpose of the study was the multifaceted and complex analysis of the impact behaviour of hybrid titanium glass fibres laminates (HTGL) based on the experiment method. Moreover the appropriate model to prediction of impact damage resistance was proposed. Different quantitative and qualitative criteria were used to measure and compare the impact behaviour of HTGL. • Based on impact parameters and damage analysis of HTGL after impact, FEM model was proposed to predict the impact resistance of HTGL. • Based on the obtained results of experimental studies it was proven that fibre metal laminates based on titanium and glass-epoxy composite are characterised by high resistance to low-velocity impact. • Greater resistance of these laminates to damage propagation and perforation was noted for the impact with a spherical indenter in comparison to the previously used GLARE laminates. • Three aspects of mechanical response of FMLs, such as metal properties, composite properties and metal-composite interphase were used in the FEM simulation. Results of numerical analyses indicate the correctness of the adopted calculation assumptions and the study procedure itself. Fibre metal laminates (FML) constitute a group of hybrid materials made of alternating layers of metal and fibre polymer composite. One of the more prospective materials of the next FML generation is a laminate based on titanium and glass or carbon fibres. The use of titanium increases laminate stiffness in comparison to laminates based on aluminium alloys and significantly increases the corrosion resistance and impact properties. The purpose of the study was a multifaceted and complex analysis of the impact behaviour of hybrid titanium glass fibres laminates (HTGL) based on the experiment and modelling methods. Based on the obtained results of experimental studies it was proven that fibre metal laminates based on titanium and glass-epoxy composite are characterised by high resistance to low-velocity impact within the range of energy of 2.5–30 J at least, expressed by the criteria of maximum force, deformations, work performed by the indenter, impact energy absorption capacity, and the parameters describing the extent of damage after impact. The obtained results of numerical analyses indicate the correctness of the adopted calculation assumptions and the study procedure itself. [ABSTRACT FROM AUTHOR]

Abstract The paper presents the failure analysis of compressed channel section profile made of GFRP material. Three symmetrical arrangements of layers were considered: [90/0/90/0]s, [90/-45/45/0]s, [45/-45/90/0]s. In order to characterize the failure process, visual inspection, ultrasonic phased array, non-destructive testing and computer microtomography were used. Damage analysis based on studies of external and internal damage of investigated structure allowed for identification of characteristic failure modes and mechanisms. It was shown that the dominant form of destruction in the quasi-orthotropic system are matrix cracks coupled with the presence of extensive delamination while in quasi-isotropic systems more concentrated damage was noticed, in which the cracking/rapture of fibers localized in the column’s corners determined the initiation of the failure mechanism and the carrying capacity loss. In addition, it was noted that the fiber directions of the outer layers determined the directions of matrix cracks and delamination propagation. [ABSTRACT FROM AUTHOR]

Selected genes were analyzed in silico in three species: red fox ( Vulpes vulpes ), raccoon dog ( Nyctereutes procyonoides ), and dog ( Canis lupus familiaris ). This type of analysis exemplifies current and potential research on gene expression. Four nucleotide sequences, of the genes IGF1 , MYO15A , PAX3 and MC1R , were obtained from the NCBI online database. The analyses focused on the presence of CpG islands and two analytical techniques, BSP and MSP. The results from three computer programs, CpG Island Searcher ® , BiSearch ® and MethPrimer ® , were discussed in detail. The applications were compared in terms of their functionality and usefulness. [ABSTRACT FROM AUTHOR]

• The objective were Hybrid Titanium Carbon Laminates as a second generation of FML. • The fibre orientation in HTCL has a significant influence on damage propagation. • Dominant failure occurs at the metal/composite and composite/composite interfaces. • HTCL can be an appropriate solution for materials under dynamic loads. Impact resistance is one of the more critical and important features of composite materials used in the aerospace industry. The objective of work was to evaluate the hybrid titanium carbon laminate resistance to dynamic loads. The paper utilizes numerous criteria for evaluation of impact behaviour of materials, including force change, energy absorption characteristics and failure identification. To thoroughly analyze the damage mechanism, a detailed fractography of laminate destruction was performed. Moreover, an empirical model for determining the universal impact behaviour coefficient of fibre metal laminate (FML) was proposed. The first significant force fluctuations prove to reach the laminate's impact resistance limit as caused by the initiation of cracking of respective layers and the consequent reduction of laminate rigidity. A growing proportion of absorbed energy in the case of growing impact energies, from some 50% in case of 2.5 J of energy, up to circa 80% in case of 30 J of energy was recorded. Reduction of interlayers with crossing fibers fosters the creation of cracks in the lower layer of titanium due to the limited capability of partial absorption of energy through delamination. [ABSTRACT FROM AUTHOR]

In the event of fires, natural disasters, and other events associated with high temperature, bones and teeth are the only source of genetic material for identifying human or animal carcasses. To obtain reliable final results of identification tests, the use of appropriate nucleic acid extraction methods is crucial. Therefore, the main objective of this research was to evaluate the effectiveness of selected methods of DNA isolation from animal burnt bones and teeth. In addition, the effect of the duration of high temperature on the stability of nuclear and mitochondrial DNA in these tissues was determined, as well as the possibility of using the genetic material obtained for species identification of remains of unknown origin. Bones and teeth collected during necropsy of dogs were burnt in a laboratory oven at 400 °C (752 °F; 673.15 K) for 5, 10, 15, 30, 45 and 60 min. DNA was isolated according to four different protocols, using three commercial kits, i.e. the PrepFiler® Forensic DNA Extraction Kit from Applied Biosystems, the QIAamp® DNA Investigator Kit from QIAGEN, and the DNA Mini Kit from Syngen, as well as a classic organic method. The effectiveness of these methods was compared by assessing the amount of isolated DNA using Real-Time PCR and its purity using a NanoDrop™ spectrophotometer. Each isolate was also subjected to PCR with primers designed to amplify fragments of dog mitochondrial DNA. The effectiveness of species identification was assessed for the method showing the best DNA recovery and for the organic method, considered the gold standard for analysis of difficult material. The QIAamp® DNA Investigator Kit showed the highest efficiency of DNA isolation from bones and teeth burnt for 15 min (the longest burning time for which DNA could still be recovered from bones and teeth). The results of the experiment clearly indicate that DNA stability in hard tissues depends on how long they burn. In the case of exposure to 400 °C, reliable genetic testing, including species identification, is possible when the burning time does not exceed 15 min. Among the hard tissues examined, bones proved more suitable than teeth for identification purposes. It was also concluded that identification of bone remains with extreme heat damage should be based on mitochondrial DNA analysis. [ABSTRACT FROM AUTHOR]

• Use of thin-ply FMLs is a prospective material solution for innovative applications. • Thin-ply FMLs do not show a significant change in impact damage mechanisms. • Use of thin-ply carbon fibres in FMLs with not lead to higher impact resistance. • Thin-ply FMLs showed the brittle failure and in situ effect. This study present investigation on the low-velocity impact resistance of fibre metal laminates consisting of aluminium layers and a thin-ply carbon fibre reinforced polymer. A thin-ply effect is compared with fibre metal laminates consisting of conventional thickness plies. Low-velocity impact tests are conducted with impact energies ranging from 2.5 J to 30 J. The low-velocity impact behaviour of conventional and thin-ply laminates is estimated and compared by analysis of key characteristics describing impact during the impactor-laminate contact. In addition, impact damage of the laminates is analysed, focusing on the identification of dominant damage modes and locations. Results demonstrate that the use of a thin-ply carbon fibre reinforced polymer neither increases the low-velocity impact resistance of the laminates nor significantly changes their low-impact impact response as compared to the laminates with conventional ply thickness. Results demonstrate that the damage mechanism of the composite thin plies does not significantly differ from that of the conventional carbon plies. Results also confirm that the use of thin-ply fibre metal laminates is an interesting and promising materials solution. [ABSTRACT FROM AUTHOR]

Abstract The effect of impact load with low velocity in thin-walled plates and profiles has been investigated. The paper deals with the relation between damage propagation, size and shape as a function of boundary conditions, layer arrangements and impact energy. The structures under consideration were made of eight-layer Glass Fiber Reinforced Polymer (GFRP) laminate with a quasi-isotropic, quasi-orthotropic and angle ply arrangement of layers. The standardised plates predefined to CAI tests and channel section profiles have been subjected to impact load. Based on the performed tests, the impact characteristics have been obtained and compared with the theoretical model (one degree of freedom mass-spring system). Further, despite it not being mentioned in the ASTM 7136 standard, characteristic curves were identified. It was noted that the impacts introducing matrix damages and the partial fracture of the fibres significantly change the course of the Force-Time histories, particularly after the maximum impact force is reached. [ABSTRACT FROM AUTHOR]