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Gıda endüstrisinde, geleneksel yöntemlere alternatif olabilecek yeni muhafaza ve işleme teknolojilerinin kullanımı giderek önem kazanmaktadır. Bu yeni ve özellikle ısıl olmayan tekniklerin gıdaların güvenliğini arttırma, kalite kayıplarını azaltma, üretimde verim artışını sağlama gibi çok önemli avantajları bulunmaktadır. Bu yeni teknolojilerden biri olan Vurgulu Elektrik Alan (Pulsed Electric Field-PEF) tekniği, son yıllarda üzerinde önemle durulan bir yöntem olarak göze çarpmaktadır. Bu yöntem hem sıvı hem de katı gıdalarda değişik amaçlarla kullanılmakta olup optimizasyona yönelik çeşitli çalışmalar yapılmaktadır. Diğer yandan, PEF tekniğinin et ve su ürünlerinde de gerek muhafaza amacıyla, gerekse diğer meydana getirdiği olumlu özellikler (ürünün fonksiyonel özelliklerini geliştirmesi, kurutma, kürleme ve dondurma gibi işlemleri hızlandırması) nedeniyle kullanımına dair yakın zamanda çeşitli çalışmalar mevcuttur. Bu bakımdan bu derleme çalışmasında, PEF tekniğinin et ve su ürünlerinde hangi amaçlar için kullanılabileceği üzerine detaylı bilgiler verilmeye çalışılmıştır.

In this study, traditional pickled pepper was produced in 3 different formulations by using whey cheese and cheese crumbs, which are obtained as a by-product in the cheese-making process. In the scope of the study, the microbiological, chemical and sensory properties were examined during the 5 months of storage period. The initial E. coli contents of the samples were determined as 3.71, 2.73, 4.72 log cfu/g respectively and it was not detected in any of the group at the end of the 21st day. The 2nd group was the most acceptable in terms of taste (5.9-6.6), smell (6.2-6.6) and visual appearance (6.3-6.7) for 4 months. It was observed that there was no change in the chemical parameters of all groups that could negatively affect consumption during the storage period. As a result of the study, it was shown that a high value-added product can be produced by using dairy by-products. Bu çalışmada, süt endüstrisinde yan ürün olarak elde edilen düşük katma değerli kırık peynirler ve lor peyniri kullanılarak 3 farklı formülasyonda geleneksel peynirli (sütlü) biber üretimi gerçekleştirilmiştir. Çalışma kapsamında, ürünlerin mikrobiyolojik, kimyasal ve duyusal özellikleri 5 aylık depolama süresi boyunca incelenmiştir. Mikrobiyolojik analizlere göre, örneklerin başlangıçtaki E. coli içeriği sırasıyla 3.71, 2.73, 4.72 log kob/g olarak belirlenmiş ve 21. günün sonunda hiçbir grupta tespit edilmemiştir. Duyusal analiz sonuçlarına göre, 2. grup 4 ay boyunca tat (5.9-6.6), koku (6.2-6.6) ve görsel açıdan (6.3-6.7) en çok beğenilen grup olmuştur. Kimyasal analiz sonuçları göz önüne alındığında ise, depolama süresince tüm grupların parametrelerinde tüketimi olumsuz yönde etkileyebilecek bir değişikliğin olmadığı gözlenmiştir. Çalışma sonucunda, süt endüstrisi yan ürünleri kullanılarak katma değeri yüksek bir ürünün üretilebileceği ortaya konmuştur.

Zeytin ağacının meyvesinden hiçbir saflaştırma (rafinasyon) işlemine tabi olmadan sadece mekanik veya diğer fiziksel yöntemlerle elde edilen natürel (doğal) zeytinyağının (Virgin olive oil, VOO) üretim süreci son yıllarda stabil kalmıştır. Günümüzde ise, kaliteli natürel zeytinyağlarının endüstriyel anlamda üretilebilmesi için geleneksel kesikli üretimin, sürekli üretim sistemine dönüştürülmesi ve üretim kapasitelerinin iyileştirilmesi için gelişmiş makinelerin tasarlanması ve oluşturulması amaçlanmaktadır. Bu bakımdan, gıda ürünlerinin işlenmesinde keşfedilen yeni teknolojilerden biri olan vurgulu elektrik alan (Pulsed electric field, PEF) uygulaması, birçok gıdanın işlenmesinde başarılı bir şekilde uygulanabildiği gibi natürel zeytinyağının üretiminde de verimi arttırmak ve aynı zamanda yüksek kalitede son ürün elde etmek için önerilmektedir. Bu derlemede, PEF işleminin temel prensipleri ile bu tekniğin zeytinyağının üretim verimine etkisi ve son ürünün kalitesi üzerindeki rolünün ortaya konması amaçlanmıştır.

Şekerleme endüstrisi, listenin neredeyse sınırsız olduğu, her yaş grubu tarafından talep gören, açlık ve susuzluğu gidermenin ötesinde özellikle haz almak amacıyla tüketilen çeşitli ürünleri içermektedir. Söz konusu ürünlerin yüksek kalorili olması, aşırı tüketimlerinin özellikle fazla şeker alımı ile ilişkilendirilebilen çeşitli hastalıklara neden olması ve tüketicilerin daha sağlıklı ürün gruplarına yönelmesi gibi nedenler, diğer gıda sektörlerinde olduğu gibi bu sektörde de üretilen ürünlere yönelik birtakım değişikliklerin yapılmasını zorunlu kılmıştır. Bu bakımdan günümüzde araştırmacılar, sektörde var olan şekerleme ürünlerinin üretiminde ve ürün içeriğinde değişiklikler yapıp, farklı ve yenilikçi yaklaşımlar kullanarak henüz yeni olan fonksiyonel şekerleme ürünlerinin üretimi üzerinde çalışmaktadırlar. Bu çalışma kapsamında, şekerleme endüstrisinde yoğun bir şekilde üretilen ve oldukça rağbet gören, sert şeker, yumuşak şeker, çikolata ve sakız ürünlerine fonksiyonellik kazandırılması amacıyla yapılan bilimsel çalışmalar derlenmiştir.

In this study, dried grape (Cabernet sauvignon) pomace (DGP) as a by-product of wine production was used in the chocolate spread (CS) instead of various amounts of sugar and milk originated powders (MOP; skimmed milk and demineralized whey powder 1:1, w/w). The formulations of CS samples were determined using mixture design method. The sugar, MOP and DGP concentrations changed between 35 and 50, 0.066-8.000 and 0.23-15 g/100 g, respectively. According to the results, the consistency coefficient (K) and flow behavior index values of CS samples changed between 8.10 and 28.50 Pas.s(n) and 0.52-0.71, respectively. In addition, firmness and spreadability parameters were determined between 0.80-1.42 N and 2.15-4.24 N mm, respectively. Total phenolic content in CS samples ranged from 3415 to 13,754 mg GAE/kg and their digestibility ranged between 25% and 84%. Also, the digestibility of resveratrol was determined between 47.6% and 95.7% at different DGP concentrations. All of the established models successfully described the relation with R-2 values higher than 0.800. Textural and rheological parameters as well as sensory characteristics of the samples indicated that DGP may be used as a healthy and low-cost ingredient in CS formulation to partially substitute sugar and MOP. Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [TOVAG-2170054] This work was funded by the Scientific and Technological Research Council of Turkey (TUBITAK), Project No: TOVAG-2170054.

Nowadays, the use of plant-based by-products obtained after food processing has gained importance, as these products are nutritious and cheap. The aim of this study was to determine the effects of grape skin and seed powders with different particle sizes (100, 200, 288 and 415 μm) on the texture, sensory, color, and rheological properties of soft candies. According to the results, the particle size of the grape-derived components was a significant factor for the texture parameters, especially hardness, adhesiveness, chewiness, and resilience. In sensory analyses, samples containing grape seed and skin powder with a particle size of 100 and 200 μm received the highest score and particles were not felt by the panelists. Also, the use of grape seed and skin powder decreased the L* value of the soft candies compared to the control group, which was parallel to the decrease in the particle size. It was found that r values of model fitting of rheological data can be correlated with sensory results. In conclusion, it was shown that grape-derived components can be successfully used in the formulation of soft candy if particle size was adjusted below 200 μm.

This study investigates damage mechanisms and deformation of honeycomb sandwich structures reinforced by functionally graded face plates under ballistic impact. The honeycomb sandwich structure consists of two identical functionally graded face sheets, having different material compositions through the thickness, and an aluminum honeycomb core. The functionally graded face sheets consist of ceramic (SiC) and aluminum (Al 6061) phases. The through-thickness mechanical properties of face sheets are assumed to vary according to a power-law. The locally effective material properties are evaluated using the Mori–Tanaka scheme. The effect of material composition of functionally graded face sheets on the ballistic performance of honeycomb sandwich structures was investigated using the finite element method and the penetration and perforation threshold energy values on ballistic performance and ballistic limit of the sandwich structures are determined. The contribution of the honeycomb core on the ballistic performance of the sandwich structure was evaluated by comparing with spaced plates (without honeycomb core) in terms of the residual velocity, kinetic energy, and damage area.

This paper presents the results of an experimental and numerical study on aluminium honeycomb sandwich structures under low-velocity impact loadings. In order to investigate the impact behavior of honeycomb sandwich structures, which is consisted of two identical aluminium facesheets and an aluminium honeycomb core, an experimental study was carried out by using a drop-weight impact test system. Using this system, the contact forces and absorbed energies were measured to determine the influence of impact energy for one configuration of the sandwich structure. According to these results, a numerical model by finite element method of sandwich structures was developed, which is in good agreement with experimental results in terms of contact forces and deformations. Later, the effect of the cell size and the height variation of aluminum honeycomb core on the impact response of sandwich structures were investigated using the improved numerical model. The obtained numerical and experimental results were interpreted in detail.

The study presents a comparative numerical investigation on ballistic performance of ceramic/metal armor structures. 2D axisymmetric numerical model was developed for ballistic impact simulations using LS-DYNA ® finite element software. The armor structures included combinations of boron carbide (B 4 C), Al6061-T6 and 4340 steel constituents. The interfaces in the armor structure were modelled with an epoxy resin adhesive. In order to define proper material behavior, Johnson-Holmquist-Ceramics material model for B 4 C and Plastic-Kinematic material model for Al6061-T6, 4340 steel and epoxy resin was used . The armor structures were subjected to 7.62 mm ogive-nosed steel projectile impact. In the first section, the influence of back plate material on the ballistic performance of the armor structure for bi-layers ceramic/metal configuration (ceramic front face and metal back plate) was investigated for Al6061-T6 and 4340 steel materials under same thickness and areal density. In the second section, the effect of removing half thickness of the metal constituent from the back plate and placing on the front face was investigated for both Al6061-T6 and 4340 steel materials. Finally, the influence of adhesive thickness on the ballistic performance of the armor structure was investigated. Perforation response of the armor structures were examined in terms of residual velocity of the projectile and damage mechanisms of the armor structure.

The aim of this study is to determine the ballistic impact response of a novel sandwich structure consisting of aluminum honeycomb and Al/SiC functionally graded face sheets and develop a compatible numerical model with experiments. The experiments were carried out by a single-stage gas gun system and numerical simulations were performed using the explicit finite element code, LS-DYNA (R). The mechanical properties of the functionally graded face sheets through the thickness were considered in accordance with a power-law distribution. The Mori-Tanaka scheme was used in order to determine the effective material properties of the functionally graded face sheets at a local point. In order to simulate the elastoplastic behavior of the functionally graded face sheets, Tamura-Tomota-Ozawa model was implemented in the numerical model. The ballistic performance of the sandwich structure was investigated for metal-rich (n=0.1), linear (n=1.0), and ceramic-rich (n=10.0) compositions of the functionally graded face sheets. The results indicated that the ceramic fraction of the functionally graded face sheets was quite influential on energy absorption capability, damage mechanism, and impact resistance of the sandwich structure. The sandwich structure with linear functionally graded face sheets showed the highest ballistic performance in terms of damage and deformation shapes of the entire sandwich structure among investigated material compositions., The aim of this study is to determine the ballistic impact response of a novel sandwich structure consisting of aluminum honeycomb and Al/SiC functionally graded face sheets and develop a compatible numerical model with experiments. The experiments were carried out by a single-stage gas gun system and numerical simulations were performed using the explicit finite element code, LS-DYNA®. The mechanical properties of the functionally graded face sheets through the thickness were considered in accordance with a power-law distribution. The Mori–Tanaka scheme was used in order to determine the effective material properties of the functionally graded face sheets at a local point. In order to simulate the elastoplastic behavior of the functionally graded face sheets, Tamura–Tomota–Ozawa model was implemented in the numerical model. The ballistic performance of the sandwich structure was investigated for metal-rich (n = 0.1), linear (n = 1.0), and ceramic-rich (n = 10.0) compositions of the functionally graded face sheets. The results indicated that the ceramic fraction of the functionally graded face sheets was quite influential on energy absorption capability, damage mechanism, and impact resistance of the sandwich structure. The sandwich structure with linear functionally graded face sheets showed the highest ballistic performance in terms of damage and deformation shapes of the entire sandwich structure among investigated material compositions.

A comparative numerical investigation on low-velocity impact response of a metal/ ceramic functionally graded sandwich beam (FGSB) is performed by the commercial finite element (FE) software, LS-DYNA[Formula: see text]. The mechanical properties of the FG core are represented by a power-law depending on the volume fractions of the constituents. The effective elastic properties and elastoplastic behavior of the FG core are defined by Mori–Tanaka method and TTO (Tamura–Tomota–Ozawa) model, respectively. The effects of number of layers, compositional gradient, impact energy, and impact side are investigated. The simulation results indicated that both number of layers and compositional gradient have almost no effect on the kinetic energy history. In other respects, the compositional gradient exhibits a considerable effect, and the number of layers has a minor effect on the contact force history. Increasing impact energy does not have a considerable effect in terms of number of layers whereas it exhibits a significant effect in terms of compositional gradient on the percentage difference between the peak contact forces. Finally, the impact side does not influence the contact force history for all number of layers and compositional gradients.

The three-dimensional impact behaviours of functionally graded (FG) circular plates were studied under a drop-weight. The functionally graded circular plate was composed of ceramic (SiC) and metal (Al) phases and the through-thickness mechanical properties through the region between the metal and ceramic layers vary continuously according to a power-law distribution of the volume fraction of the ceramic. The through-thickness material properties of the FG circular plate were determined using the Mori-3Tanaka scheme. The effects of layer number and compositional gradient exponent as well as impactor velocity and plate radius on the elastic impact response of the FG circular plates were investigated. The compositional gradient exponent, impactor velocity and plate radius played an important role on the impact response of the FG circular plates, whereas the layer number through the plate thickness had a minor effect. In addition, the failure strains in all layers were determined using Tamura-Tomota-Ozowa (TTO) model in order to predict the damage regions in each layer through the thickness of FG circular plates. (C) 2010 Elsevier Ltd. All rights reserved.

Geometrically nonlinear analysis of functionally graded circular plates subjected to mechanical and thermal loads is carried out in this paper. The Green–Lagrange strain tensor in its entirety is used in the analysis. The locally effective material properties are evaluated using homogenization method which is based on the Mori–Tanaka scheme. In the case of thermally loaded plates, the temperature variation through the thickness is determined by solving a steady-state heat transfer (i.e. energy) equation. As an example, a functionally gradient material circular plate composed of zirconium and aluminum is used and results are presented in graphical form.

Konjuge linoleik asit (KLA), yağ asidi zincirinde iki adet doymamıfl çift bağ içeren linoleik asidin (LA)çeflitli pozisyonel ve geometrik izomerlerini ifade etmektedir. İzomerler, LA'nın gevifl getiren hayvanlarınrumeninde stearik aside bakteriyel biyohidrojenasyonu esnasında ara ürün olarak veya memeli salgıbezi ve adipoz dokularında ?9-desaturaz enzimi aracılığıyla trans vaksenik asidin desatürasyonu ilesentezlenmektedir. KLA izomerleri birçok gıdada bulunmakla birlikte ağırlıklı olarak gevifl getirenhayvanlardan elde edilen et ve süt ürünlerinde bulunmaktadır. KLA izomerlerinin sağlık üzerine çeflitliolumlu etkilerinin olduğu, bununla beraber oluflturabilecekleri potansiyel endifleler de bazı arafltırmalardabelirtilmifltir. KLA üretimi sadece rumen bakterilerine özgü olmayıp; bazı laktik asit ve propiyonik asitbakterilerinin yanı sıra süt ürünlerinden, insan ve hayvan bağırsağından izole edilen mikroorganizmalarında üretimde yer aldığı belirlenmifltir. Bu türlerin baflta süt endüstrisi olmak üzere gıda sanayinde KLAile zenginlefltirilmifl geleneksel veya yeni fermente ürünlerin üretiminde kullanılması büyük önem arzetmektedir Conjugated linoleic acid (CLA) is a common term of various positional and geometric isomers of linoleicacid (LA) which contains two unsaturated double bonds in the fatty acid chains. Isomers are synthesizedas an intermediate product during the bacterial biohydrogenation of LA to stearic acid in the rumen ofruminants or from the conversion of trans vaccenic acid by the ?9-desaturase enzyme in the mammaryglands and adipose tissues. CLA isomers are found in many foods, but mainly present in meat and dairyproducts obtained from ruminant animals. Although there are diverse positive effects of CLA isomerson health, some potential concerns that can be caused by these compounds have been stated in somestudies. CLA production is not specific to rumen bacteria; it was determined that some lactic acid andpropionic acid bacteria as well as microorganisms isolated from the milk products, human and animalintestines involved in the production. Therefore, use of these microorganisms in food industry, especiallywithin the dairy branch, for the production of traditional or new fermented products enriched with CLAis a great importance

In this study, three-dimensional free vibration and stress analyses of an adhesively bonded functionally graded single lap joint were carried. The effects of the adhesive material properties, such as modulus of elasticity, Poisson's ratio and density were found to be negligible on the first ten natural frequencies and mode shapes of the adhesive joint. Both the finite element method and the back-propagation artificial neural network (ANN) method were used to investigate the effects of the geometrical parameters, such as overlap length, plate thickness and adhesive thickness; and the material composition variation through the plate thickness on the natural frequencies, mode shapes and modal strain energy of the adhesive joint. The suitable ANN models were trained successfully using a series of free vibration and stress analyses for various random geometrical parameters and compositional gradient exponents. The ANN models showed that the support length, the plate thickness and the compositional gradient exponent played important role on the natural frequencies, mode shapes and modal strain energies of the adhesive joint whereas the adhesive thickness had a minor effect. In addition, the optimal joint dimensions and compositional gradient exponent were determined using genetic algorithm and ANN models so that the maximum natural frequency and the minimum modal strain energy conditions are satisfied for each natural frequency of the adhesively bonded functionally graded single lap joint. (c) 2006 Elsevier Ltd. All rights reserved.

In this study three-dimensional elastic stress state of an adhesively bonded single lap joint with functionally graded adherends in tension was investigated. The adherends compose of a functionally gradient layer between a pure ceramic (Al2O3) layer and a pure metal (Ni) layer. Stress concentrations are observed along the free edges of the adhesive layer and through the corresponding zones in the upper and lower adherends. The adhesive layer experiences stress concentrations along the left and right free edges in the horizontal plane, and the normal stresses and the shear stress are critical. Whereas the middle overlap region has a uniform low stress distribution the zones in the upper adherend corresponding to the left free edge of the adhesive layer and the zones in the lower adherend corresponding to the right free edge of the adhesive layer are subjected to higher stresses. The normal stress sigma(xx) among the normal stresses and the shear stress sigma(xy) among the shear stresses are dominant in both upper and lower adherends. The normal stress sigma(xx) changes uniformly from compression in the ceramic layer to tension in the metal layer through the upper plate-thickness and from tension in the ceramic layer to compression in the metal layer through the lower plate-thickness. In the adhesive layer, the normal stress sigma(yy) becomes peak at the left free edge of the upper adherend-adhesive interface and at the right free edge of the lower adherend-adhesive interface and then decreases uniformly across the adhesive layer towards the other adherend-adhesive interface. The functionally gradient region across the adherend thickness was modelled using the layers with the mechanical properties calculated based on the power law. However, a layer number larger than 20 has a minor effect on the through-thickness profiles and magnitudes of von Mises and normal stresses in both the adherends and the adhesive. In addition, increasing the ceramic phase in the material composition (compositional gradient exponent n) of the functionally gradient region does not affect the through-thickness profiles of von Mises and normal stresses in the adherends and adhesive whereas their magnitudes in the ceramic rich layer of both adherends and along the adherend-adhesive interfaces increase considerably. On the contrary, the layer number and compositional gradient exponent have an evident effect on the through-thickness profiles and magnitudes of the critical stress components in the adherends and adhesive layer of the functionally graded adhesively bonded joints. (C) 2004 Elsevier Ltd. All rights reserved.

Adhesive bonding technique is used successfully for joining the carbon fibre reinforced plastics to metals or composite structures. A good design of adhesive joint with either simple or more complex geometry requires its stress and deformation states to be known for different boundary conditions. In case the adhesive joint is subjected to thermal loads, the thermal and mechanical mismatches of the adhesive and adherends cause thermal stresses. The plate-end conditions may also result in the adhesive joint to undergo large displacements and rotations whereas the adhesive and adherends deform elastically (small strain). In this study, the thermal and geometrically non-linear stress analyses of an adhesively bonded composite tee joint with single support plus an angled reinforcement made of unidirectional CFRPs were carried out using the non-linear finite element method. In the stress analysis, the effects of the large displacements were considered using the small displacement–large displacement theory. The stress states in the plates and the adhesive layer of the tee joint configurations bonded to a rigid base and a composite plate were investigated. An initial uniform temperature distribution was attributed to the adhesive joint for a stress free state, and then variable thermal boundary conditions, i.e. air flows with different velocity and temperature were specified along the outer surfaces of the tee joints. The thermal analysis showed that a non-uniform temperature distribution occurred in the tee joints, and high heat fluxes took place along the free surfaces of the adhesive fillets at the adhesive free ends. Later, the geometrical non-linear thermal-stress analysis of the tee joint was carried out for the final temperature distribution and two edge conditions applied to the edges of the vertical and horizontal plates (HP). High stress concentrations occurred around the rounded adherend corners inside the adhesive fillets at the adhesive free ends, and along the adhesive–composite adherend interfaces due to their thermal–mechanical mismatches. The most critical joint regions were adhesive fillets subjected to high thermal gradients, the middle region of HP, the region of the vertical plate corresponding to the free end of the vertical adhesive layer–left support interface. In addition, the support length had a small effect of reducing the peak stresses at the critical adherend and adhesive locations.

In this study, the. geometrically non-linear thermal stress analysis of an adhesively bonded tubular single lap joint subjected to airflows having different temperature and velocity outside and inside its inner and outer tubes was carried out using the incremental finite element method. Since the thermal expansion coefficients of tubes and adhesive were different the thermal strains arising along the adhesive-tube interfaces resulted in high thermal stresses in the adhesive layer and tubes for different end conditions applied to the ends of its outer and inner tubes. The joint region was considerably deformed, and serious stress concentrations occurred around the adhesive free ends. This effect became more evident in cases the tube edges were fully restrained. The peak thermal adhesive and tube stresses occurred at the free ends, of the adhesive-tube interfaces. In addition, increasing the overlap length had an effect of reducing the peak adhesive and tube stresses, and an optimum overlap length/joint length ratio of 0.2 was determined. (C) 2002 Elsevier Science B.V. All rights reserved.

This study investigates damage mechanism and deformation of honeycomb sandwich structures reinforced by functionally graded plates under ballistic impact effect by means of explicit dynamic analysis using ANSYS LS-DYNA. The honeycomb sandwich structures consisted of two identical functionally graded (FG) facesheets having different material compositions through the plate thickness and an aluminum honeycomb core. The functionally graded facesheets were composed of ceramic (SiC) and metal (Al6061) phases. The through-thickness mechanical properties of facesheets were determined based on a power-law distribution of the volume fraction of the constituents. The locally effective material properties were evaluated using homogenization method which based on the Mori-Tanaka scheme. In the analyses, theoretical models which based on micro structural model of functionally graded materials were used. The effect of material composition of functionally graded facesheets on the ballistic performance of honeycomb sandwich structures was investigated and the penetration and perforation threshold energy values which are the most considerable parameters on ballistic performance and ballistic limit of the sandwich structures were determined.

Functionally graded materials have been increasingly used in the design of impact resistant structures. A functionally graded plate with a tailored ceramic to metal through-thickness gradient combines the superior features of ceramics and metals in the same material system. The ceramic-rich side provides good protection against projectiles, while the metal-rich side oers toughness and strength to maintain the integrity of the structure as much as possible. Thus, the ceramic plates are used for single impact applications, whereas the FGM can be used multiple impact applications with high ballistic performance. In this study, the damage and deformation mechanisms of aluminum plates and functionally graded sandwich plates have been investigated and their performances were compared to each other under ballistics impact loadings. The functionally graded sandwich plate is composed of a mixture of ceramic (SiC) and metal (Al) phases, at a ratio of which is determined by a power-law distribution of the volume fraction. In the ballistics tests with 9 mm Parabellum projectiles, having a brass jacket and a lead core were used. Both aluminum and functionally graded sandwich plates were manufactured by means of the powder stacking-hot pressing method, their ballistic tests were performed and it was determined that functionally graded sandwich plates have a better ballistics performance than an aluminum plate by examining almost a full penetration of projectile to the aluminum plate while a signicant penetration to the functionally graded sandwich plate was not observed.

This paper addresses low-velocity impact behaviour of functionally graded clamped circular plates. An experimental work was carried out to investigate the impact behaviour of FG circular plates which is composed of ceramic (SiC) and metal (Al) phases varying through the plate thickness by using a drop-weight impact test system. The influence of the compositional gradient exponent and impactor velocity on the contact forces and absorbed energies was concentrated on the tests. The explicit finite element method, in which a volume fraction based elastic plastic model (the TTO model) was implemented for the functionally graded materials, was used to simulate their drop-weight impact tests. Effective material properties at any point inside FGM plates were determined using Mori-Tanaka scheme. The experimental and numerical results indicated that the compositional gradient exponent and impactor velocity more effective on the elasto-plastic response of the FG circular plates to a low-velocity impact loading. The comparison at the theoretical and experimental results showed that the use of the TTO model in modelling the elasto-plastic behaviour of FG circular plates results in increasing deviations between the numerical and experimental contact forces for ceramic-rich compositions whereas it becomes more successful for metal-rich compositions. (C) 2013 Elsevier Ltd. All rights reserved., This paper addresses low-velocity impact behaviour of functionally graded clamped circular plates. An experimental work was carried out to investigate the impact behaviour of FG circular plates which is composed of ceramic (SiC) and metal (Al) phases varying through the plate thickness by using a drop-weight impact test system. The influence of the compositional gradient exponent and impactor velocity on the contact forces and absorbed energies was concentrated on the tests. The explicit finite element method, in which a volume fraction based elastic–plastic model (the TTO model) was implemented for the functionally graded materials, was used to simulate their drop-weight impact tests. Effective material properties at any point inside FGM plates were determined using Mori–Tanaka scheme. The experimental and numerical results indicated that the compositional gradient exponent and impactor velocity more effective on the elasto-plastic response of the FG circular plates to a low-velocity impact loading. The comparison at the theoretical and experimental results showed that the use of the TTO model in modelling the elasto-plastic behaviour of FG circular plates results in increasing deviations between the numerical and experimental contact forces for ceramic-rich compositions whereas it becomes more successful for metal-rich compositions.

In this study, the interaction between the Nitinol stent and the artery with plaque was investigated using finite element method. The occurring pressure values during the cardiac contraction (systolic) and loosening (diastolic) were applied as loading to the modeled system with Nitinol stent. In the light of the stress values, the suitability of the Nitinol stent in an artery with plaque was investigated. In the analysis, Nitinol stent was assumed to be shape memory alloy, and artery and plaque were assumed to behave linearly elastic. As a result, the stress and deformations in the plaque and artery due to the interference of Nitinol stent were discussed and concluded that the structure of artery with plaque can be expanded in accordance with Nitinol stent.

This experimental study addresses the effect of ceramic reinforcement on the impact performance of functionally graded (FG) circular plates. The FG circular plates were produced from two different ceramic (SiC or Al 2 O 3 ) and metal (Al) combinations using powder stacking-hot pressing technique. The Al/SiC FG circular plates exhibited better impact resistance than Al/Al 2 O 3 FG circular plates. The effect of ceramic particle size was also investigated on the impact performance of specimens with different composition variations. A ceramic particle size of 50 μm improved the impact performance. In addition, the material composition and impactor velocity also affected the impact performance. Thus, the contact force increases as the composition changes from metal-rich to ceramic-rich. The peak contact force increases with increasing the velocity of impactor.

In this study three-dimensional elasto-plastic analysis of functionally graded (FG) circular plates under low-velocity impact loads is presented The FG circular plate is composed of ceramic (SIC) and metal (AI) phases varying in a predetermined fashion through the plate thickness The elasto-plastic behaviour of the FG circular plate is described by the TTO model In the analyses the ceramic phase is taken to be an isotropic elastic material whereas the metal phase is taken to be elasto-plastic material in accordance with the TTO model The locally effective material properties were evaluated using homogenization method which is based on the Mori-Tanaka scheme The effects of compositional gradient exponent and Impactor velocity on the elasto-plastic Impact response of the FG circular plates are investigated and results are presented graphical form The compositional gradient exponent and Impactor velocity have significant effects on the elasto-plastic impact response of the FG circular plates The elasto-plastic impact response of FG circular plates is similar to those of homogeneous plates Therefore the TTO model can be used to describe the mechanical behaviour of FG plates beyond the elastic range assuming that the material response is essentially governed by the spreading of plasticity in the metal phase (C) 2010 Elsevier Ltd All rights reserved

29th Turkish Cardiology Congress of the Turkish-Society-of-Cardiology (TSC) with International Participation -- OCT 26-29, 2013 -- Antalya, TURKEY, WOS: 000329858400301, …, Turkish Soc Cardiol