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The objective is to identify optimum configuration in terms of loading, structural dimensions, material properties and composite layup associated with micrometeorites impacts on spacecraft that will not penetrate into its structure.
The impact velocity of a projectile will affect the performance of compliant and resilient laminates.
Through such analysis and numerical simulation, effort is devoted to arrive at the optimum configuration in terms of loading, structural dimensions, material properties and composite lay-up, among others.
The problem can be idealized as the loading and response characteristics of a set of bonded rectangular isotropic and homogeneous plates with different material properties, subjected under the impact of a solid and rigid spherical impactor, as depicted in Fig. 1.
(b) To appreciate the use of bi-metallic composite, Fig. 7 exhibits the response of an Aluminum/ Titanium composite with properties tabulated in Table 2 as an isotropic material.

Polymers, in addition to their economical superiority, possess a large variety of favorable physical, chemical and mechanical properties.
Cross-linking occurs in Teflon after irradiating it with gamma rays which improves its mechanical properties [58].
Chen et al. [61] modified the mechanical properties of polyimide by bombarding it with 2 MeV Si ions.
Zihlif, Examination of optical properties and estimation of mechanical energies of irradiated polypropylene and Teflon, Rad.
Wang, The modification of mechanical properties by 2 MeV Si ions irradiating polyimide, Nucl.

Introduction Single crystal nickel-base superalloys are widely used as turbine blades components in aero and industrial gas turbines since they combine good mechanical properties with microstructural stability at relatively high temperature [3].
Spallation depends on many factors such as surface roughness, surface preparation, material composition, but also cycle duration.
Cycle frequency can affect Al loss in the coating due to oxidation if it affects spallation.

According to the design mixing ratio in Table 1, test cubes of 150 × 150 × 150 are fabricated (standard recommended sizes of φ100 × 100 and φ200 × 100 are not used mainly because that if the standard recommended sizes are used, due to the constraint of the cylindrical sidewall, the side face of the shaped specimen often has significant defects, which will affect the test results).
Due to higher activity of the slag powder, the active ingredients (activated aluminum and silicon in glass state) in the slag powder react with the hydration product of the cement (referred to as secondary reaction), generating hydrated silicic acid with cementitious properties and hydrated calcium aluminate cementitious substance on the surface, which fill the cement pores and improve the concrete density, simultaneously reduce the amount of Ca (OH)2 in the cement paste, form C-S-H gels, weaken the preferred orientation of Ca (OH)2, increase the density of the interface transition zone, and improve the structure and micro-mechanical properties of the interface transition zone; in addition, the slag powder is of small particles, with larger specific surface area and stronger adsorbing and curing abilities for chloride ions, the slag powder also contains a large amount of calcium and aluminum phases, the hydrated calcium aluminate produced in the hydration can combine with the chlorine ions
Study on Dense Packing Properties of Cementitious Materials [J].
Study on Influential Factors and Assessment Indexes of Duration Property of Concrete [J].

Hence, it could be manifested from these findings that the magnitude of CP was not affected by radial tears up to 75% width [13,43].
However, it fails to take into account the variation of the material properties within the soft tissues [28].
Future Recommendations Most of the experimental studies on knee joints were done on cadaveric specimens, which lack the dynamic properties of an in-vivo model.
Hence, future studies should be directed towards approaches to preserve the dynamic properties of the soft tissues.
Vail, “Biomechanical Factors in Tissue Engineered Meniscal Repair,” Clin.

In this research, due to its commercially available, easy-to-process, high mechanical, thermal, and chemical resistance properties, polysulfone has been selected as the coating material [18].
Researchers have made great efforts to improve the properties of nanofibers.
The antibacterial properties of the PSU-Nf-AgNPs were explored against Gram-negative, Gram-positive bacteria, and model biofilm bacterium (Fig. 4).
This result clearly claimed antibacterial properties in PSU-Nf-AgNPs due to the surface-functionalized AgNPs on the nanofiber membranes.
Thus, acid corrosion was not a contributing factor in this work.

Many research groups have studied the SF/PVA blends to improve the mechanical properties of SF [15–19].
Xu, Metal ion permeation properties of silk fibroin/chitosan blend membranes, Polym.
Kuga, Structure and properties of silk fibroin–poly (vinyl alcohol) gel, Int.
Yao, Deposition behavior and properties of silk fibroin scaffolds soaked in simulated body fluid, Mater.
Gunasekaran, Selected properties of pH-sensitive, biodegradable chitosan–poly (vinyl alcohol) hydrogel, Polym.

A detailed summary of the experiments carried out so far with the fastenings embedded in UHPFRC is given in the Table 1 together with the material properties.
Vf is considered in Eq. 2 by the factor k.
However, despite the introduction of this factor, tests with vf = 2,0 % are only available.
Table 5 Failure modes of UHPFRC specimens, comparison of series (vf) and depth (hef), one sample for each type 1,5 % 2,0 % 2,5 % 25 F 25 H Not part of 1.5% series 35 F 35 H Not part of 1.5% series 45 F Influence of Parameters on Anchoring Properties Effect of fiber volume vf.
There is a significant difference between the properties of the UHPFRC from the smoothed surface (H) and from the surface from the mould (F).

Differ from the traditional concrete, HPC(High Performance Concrete) is regarded as the concrete which has the most comprehensive properties by the world because of its numerous superior properties such as high-durability, high-performance, high-strength and high-stability of volume.
C-S-H gel phase is the largest component of set cement system, although the difference on morphology is larger and the structure is not fixed, its structure is the main factor that decides the strength of set cement.
With the higher of the activity of silica powder, the strength of cement-based materials were enhanced at most, and then the secondary hydration reaction could be carried out between ultrafine powders and hydration products of cements Ca(OH)2, where after large amount of C-S-H gels would be generated, which could densify both of the slurry structure and interface transition zone, and better improve the micro-structure of cement-based materials and finally enhance the mechanical property of materials.
Through the observation of the micro-structure of cementing materials, it can be found that the joint use of slag and siliceous dust can reduce the amount of Ca(OH)2 crystal and affect its appearance; meanwhile the structure of concrete and the development of its performance can be influenced significantly.
C-S-H gel phase is the largest component of set cement system, although the difference on morphology is large and the structure is not very fixed, its structure is the main factor that decides the strength of set cement.

This is one of the factors limiting the ability of this technique to match the performance of HMA due to the non-optimal binding process of bitumen to asbuton which is associated with the incomplete extraction in asbuton.
The process of removing bitumen requires materials of the same nature and this is important to achieve a higher solubility as observed in the use of solvent molecules (solvent) and solute with similarities in structure and electrical properties based on the concept of "like dissolves like."
The existence of similarity in electrical properties usually produces a strong tensile force between the solvent and solute [25].
This method provides an initial estimate of the asphalt content selection for the mixture in laboratory or field experiments, and if necessary adjusted, to obtain the desired characteristics or special properties of the resulting asphalt mixture. 4.
H., Djamaluddin, R., “Mechanical Characteristics of Hotmix Cold Laid Containing Buton Granular Asphat (BGA) and Flux Oil as Wearing Course,” ARPN J.