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Synthesis and characterization of smart hydrogels for controlled drug release considering RAFT polymerization and SEC tetra-detection

Machado, Carla Alexandra Lopes
Fonte: Instituto Politécnico de Bragança Publicador: Instituto Politécnico de Bragança
Tipo: Dissertação de Mestrado
ENG
Relevância na Pesquisa
36.6%
Os hidrogéis inteligentes têm importantes aplicações nas áreas da biotecnologia, biomedicina, farmácia e ambiente. A libertação de fármacos ou de genes, bio separações, bio sensores e engenharia dos tecidos são alguns exemplos de processos onde esta classe de materiais avançados mostram um aumento da sua importância ao longo do tempo. Este trabalho é dedicado à síntese, caracterização e avaliação do desempenho de hidrogéis inteligentes para aplicações de adsorção e libertação (dessorção) de fármacos. Esta pesquisa pretende contribuir para o desenvolvimento de ferramentas de projeto relacionando as condições de síntese com a estrutura e a performance final neste tipo de materiais. A Polimerização Radicalar Clássica (FRP) e a Polimerização via Transferência de Cadeia Reversível por Adição-Fragmentação (RAFT) são ambas consideradas no programa experimental efetuado. O efeito da técnica de polimerização (FRP/RAFT) na estrutura e propriedades dos hidrogéis inteligentes é assim avaliada. Neste trabalho foi construído um micro reator de fluxo contínuo que permitiu a produção de partículas destes hidrogéis. A comparação da estrutura e propriedades destes materiais sintetizados em reator fechado e num micro reator de fluxo contínuo foi também feita. A impressão molecular foi considerada como o terceiro vetor de pesquisa para obter hidrogéis avançados com propriedades adaptadas. Polímeros Molecularmente Impressos (MIP) foram produzidos em reator fechado e em micro reator de fluxo continuo considerando...

Análise estática e dinâmica de estruturas delgadas de materiais compostos laminados incluindo materiais piezelétricos; Static and dynamic analysis of thin laminated composite structures with piezoelectric materials

Isoldi, Liércio André
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Tese de Doutorado Formato: application/pdf
POR
Relevância na Pesquisa
56.44%
Sabe-se que materiais compostos laminados são, hoje em dia, geralmente usados nas indústrias aeronáutica, aeroespacial, naval e outras, principalmente por causa de suas atrativas propriedades se comparadas aos materiais isotrópicos, como alta rigidez/peso, alta resistência, alto amortecimento e boas propriedades relacionadas ao isolamento térmico e acústico, entre outras. Porém, o comportamento de estruturas feitas de materiais compostos pode ser aperfeiçoado através da utilização de materiais inteligentes. Dentre os diferentes tipos comercialmente disponíveis de materiais inteligentes, os materiais piezelétricos são amplamente usados como sensores e atuadores para o monitoramento e controle de estruturas. O efeito piezelétrico direto define que uma deformação mecânica aplicada ao material é convertida em uma carga elétrica. Por outro lado, o efeito piezelétrico inverso define que um potencial elétrico aplicado ao material é convertido em deformação mecânica. Estes efeitos governam a interação eletromecânica nos materiais piezelétricos. O Método dos Elementos Finitos, uma ferramenta amplamente reconhecida e poderosa para a análise de estruturas complexas, é capaz de realizar a integração dos componentes inteligentes e das partes estruturais clássicas. Sendo assim...

An investigations on local and global behavior of a (SMA) oscillator of 3 - DOF driven by a limited power supply

Piccirillo, Vinícius; Goes, Luiz Carlos Sandoval; Balthazar, José Manoel
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 1403-1410
ENG
Relevância na Pesquisa
46.39%
SMART material systems offer great possibilities in terms of providing novel and economical solutions to engineering problems. The technological advantages of these materials over traditional ones are due to their unique microstructure and molecular properties. Smart materials such as shape memory alloys (SMA), has been used in such diverse areas of engineering science, nowadays. In this paper, we present a numerical investigation of the dynamics interaction of a nonideal structure (NIS). We analyze the phenomenon of the passage through resonance region in the steady state processes. We remarked that this kind of problem can lead to the so-called Sommerfeld effect: steady state frequencies of the DC motor will usually increase as more power (voltage) is given to it in a step-by-step fashion. When a resonance condition with the structure it is reached, the better part of this energy it is consumed to generate large amplitude vibrations of the foundation without sensible change of the motor frequency as before. The results obtained by using numerical simulations are discussed in details. Copyright © 2009 by ASME.

Análise modal de uma estrutura do tipo viga utilizando materiais piezelétricos (PVDF) como sensores

Prazzo, Carlos Eduardo
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 139 f. : il.
POR
Relevância na Pesquisa
46.27%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Pós-graduação em Engenharia Mecânica - FEIS; Esse trabalho discute o uso dos materiais piezelétricos, mais especificamente, o Polyvinylidene Fluoride (PVDF) e o Lead Zirconate Titatane (PZT) na análise modal experimental (AME) de estruturas mecânicas. Materiais piezelétricos, também chamados de materiais inteligentes, têm se consolidado como uma nova tecnologia que mostra um grande potencial de aplicação em diferentes áreas da engenharia. Esse tipo de material exibe um acoplamento entre multi-domínios físicos, como por exemplo o acoplamento eletro-mecânico, o térmo-magnético, etc. O acoplamento eletro-mecânico produz um deslocamento elétrico quando o material é sujeito a uma tensão mecânica (efeito direto) e um deformação mecânica quando esse material é submetido a um campo elétrico (efeito inverso). Assim, principalmente por conta desses efeitos, seu uso no campo da análise modal experimental torna-se uma interessante questão a ser investigada. A incorporação de novas tecnologias nos testes estruturais pode agregar novos conhecimentos e avanços tanto na análise modal baseada na relação entrada-saída da estrutura, quanto na mais recente técnica...

Monitoramento da integridade em estruturas aeronáuticas

Franco, Vitor Ramos
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 202 f. : il., fots. color.
POR
Relevância na Pesquisa
46.16%
Pós-graduação em Engenharia Mecânica - FEIS; Este trabalho apresenta o estudo e desenvolvimento de uma técnica de monitoramento da integridade estrutural, para identificação e caracterização de falhas estruturais através da metodologia das ondas de Lamb utilizando materiais piezelétricos como sensores e atuadores. Ondas de Lamb são uma forma de perturbação elástica que se propaga guiada entre duas superfícies paralelas livres. Ondas de Lamb são formadas quando o atuador excita a superfície da estrutura com um pulso depois de receber um sinal. Quando uma onda propaga na superfície de uma placa, ela chega em um PZT sensor por diferentes caminhos. Um caminho é quando a onda atinge o sensor diretamente, ou seja, sem obstáculos no caminho em que ela se propaga. Outro caminho possível é quando a onda chega ao sensor após se propagar sobre descontinuidades existentes na superfície da estrutura. Com as várias características dos sinais recebidos, e com o uso de certas técnicas de processamento de sinais, essas falhas podem ser identificadas, realizando-se a ação correta tentando evitar a total falha da estrutura. Nesse contexto, diferentes testes experimentais foram realizados em diferentes tipos de estruturas. Redes de sensores e atuadores piezelétricos foram acopladas na superfície dessas estruturas...

Applications of polymeric smart materials to environmental problems.

Gray, H N; Bergbreiter, D E
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/1997 EN
Relevância na Pesquisa
46.4%
New methods for the reduction and remediation of hazardous wastes like carcinogenic organic solvents, toxic materials, and nuclear contamination are vital to environmental health. Procedures for effective waste reduction, detection, and removal are important components of any such methods. Toward this end, polymeric smart materials are finding useful applications. Polymer-bound smart catalysts are useful in waste minimization, catalyst recovery, and catalyst reuse. Polymeric smart coatings have been developed that are capable of both detecting and removing hazardous nuclear contaminants. Such applications of smart materials involving catalysis chemistry, sensor chemistry, and chemistry relevant to decontamination methodology are especially applicable to environmental problems.

Multifunctional three-dimensional macroporous nanoelectronic networks for smart materials

Liu, Jia; Xie, Chong; Dai, Xiaochuan; Jin, Lihua; Zhou, Wei; Lieber, Charles M.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.27%
Seamless and minimally invasive integration of 3D electronic circuitry within host materials could enable the development of materials systems that are self-monitoring and allow for communication with external environments. Here, we report a general strategy for preparing ordered 3D interconnected and addressable macroporous nanoelectronic networks from ordered 2D nanowire nanoelectronic precursors, which are fabricated by conventional lithography. The 3D networks have porosities larger than 99%, contain approximately hundreds of addressable nanowire devices, and have feature sizes from the 10-μm scale (for electrical and structural interconnections) to the 10-nm scale (for device elements). The macroporous nanoelectronic networks were merged with organic gels and polymers to form hybrid materials in which the basic physical and chemical properties of the host were not substantially altered, and electrical measurements further showed a >90% yield of active devices in the hybrid materials. The positions of the nanowire devices were located within 3D hybrid materials with ∼14-nm resolution through simultaneous nanowire device photocurrent/confocal microscopy imaging measurements. In addition, we explored functional properties of these hybrid materials...

Biosmart Materials: Breaking New Ground in Dentistry

Badami, Vijetha; Ahuja, Bharat
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Publicado em 02/02/2014 EN
Relevância na Pesquisa
36.48%
By definition and general agreement, smart materials are materials that have properties which may be altered in a controlled fashion by stimuli, such as stress, temperature, moisture, pH, and electric or magnetic fields. There are numerous types of smart materials, some of which are already common. Examples include piezoelectric materials, which produce a voltage when stress is applied or vice versa, shape memory alloys or shape memory polymers which are thermoresponsive, and pH sensitive polymers which swell or shrink as a response to change in pH. Thus, smart materials respond to stimuli by altering one or more of their properties. Smart behaviour occurs when a material can sense some stimulus from its environment and react to it in a useful, reliable, reproducible, and usually reversible manner. These properties have a beneficial application in various fields including dentistry. Shape memory alloys, zirconia, and smartseal are examples of materials exhibiting a smart behavior in dentistry. There is a strong trend in material science to develop and apply these intelligent materials. These materials would potentially allow new and groundbreaking dental therapies with a significantly enhanced clinical outcome of treatments.

Smart Materials Based on DNA Aptamers: Taking Aptasensing to the Next Level

Mastronardi, Emily; Foster, Amanda; Zhang, Xueru; DeRosa, Maria C.
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 18/02/2014 EN
Relevância na Pesquisa
46.46%
“Smart” materials are an emerging category of multifunctional materials with physical or chemical properties that can be controllably altered in response to an external stimulus. By combining the standard properties of the advanced material with the unique ability to recognize and adapt in response to a change in their environment, these materials are finding applications in areas such as sensing and drug delivery. While the majority of these materials are responsive to physical or chemical changes, a particularly exciting area of research seeks to develop smart materials that are sensitive to specific molecular or biomolecular stimuli. These systems require the integration of a molecular recognition probe specific to the target molecule of interest. The ease of synthesis and labeling, low cost, and stability of DNA aptamers make them uniquely suited to effectively serve as molecular recognition probes in novel smart material systems. This review will highlight current work in the area of aptamer-based smart materials and prospects for their future applications.

Calcium powered phloem protein of SEO gene family “Forisome” functions in wound sealing and act as biomimetic smart materials

Srivastava, Vineet Kumar; Tuteja, Narendra
Fonte: Landes Bioscience Publicador: Landes Bioscience
Tipo: Artigo de Revista Científica
Publicado em 06/06/2014 EN
Relevância na Pesquisa
46.3%
Forisomes protein belongs to SEO gene family and is unique to Fabaceae family. These proteins are located in sieve tubes of phloem and function to prevent loss of nutrient-rich photoassimilates, upon mechanical injury/wounding. Forisome protein is also known as ATP independent, mechanically active proteins. Despite the wealth of information role of forisome in plants are not yet fully understood. Recent reports suggest that forisomes protein can act as ideal model to study self assembly mechanism for development of nanotechnological devices like microfluidic system application in space exploration mission. Improvement in micro instrument is highly demanding and has been a key technology by NASA in future space exploration missions. Based on its physical parameters, forisome are found to be ideal biomimetic materials for micro fluidic system because the conformational shifts can be replicated in vitro and are fully reversible over large number of cycles. By the use of protein engineering forisome recombinant protein can be tailored. Due to its unique ability to convert chemical energy into mechanical energy forisome has received much attention. For nanotechnological application and handling biomolecules such as DNA, RNA, protein and cell as a whole microfluidic system will be the most powerful technology. The discovery of new biomimetic smart materials has been a key factor in development of space science and its requirements in such a challenging environment. The field of microfludic...

Dynamic Hybrid Materials: Hydrogel Actuators and Catalytic Microsystems

Zarzar, Lauren Dell
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation
EN_US
Relevância na Pesquisa
46.24%
Dynamic materials which can sense changes in their surroundings and subsequently respond or adapt by autonomously altering their functionality, surface chemistry, transparency, color, wetting behavior, adhesiveness, shape, etc. are primed to be integral components of future "smart" technologies. However, such systems can be quite complex and often require intricate coordination between both chemical and mechanical inputs/outputs as well as the combination of multiple materials working cooperatively to achieve the proper functionality. It is critical to not only understand the fundamental behaviors of existing dynamic chemo-mechanical systems, but also to apply that knowledge and explore new avenues for design of novel materials platforms which could provide a basis for future adaptive technologies. Part 1 explores the use of environmentally-sensitive hydrogels, either alone or within arrays of high-aspect-ratio nano/microstructures, as chemo-mechanical actuators. Chapters 1 through 7 describe a bio-inspired approach to the design of hybrid actuating surfaces in which the volume-changing hydrogel acts as the “muscle” that reversibly actuates the microstructured "bone". In particular, the different actuation mechanisms arising from variations in how the hydrogel is integrated into the structure array...

Multifunctional three-dimensional macroporous nanoelectronic networks for smart materials

Liu, Jessica C; Xie, Chong; Dai, Xiaochuan; Jin, Lihua; Zhou, Wei; Lieber, Charles M.
Fonte: Proceedings of the National Academy of Sciences Publicador: Proceedings of the National Academy of Sciences
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
46.27%
Seamless and minimally-invasive integration of three-dimensional (3D) electronic circuitry within host materials could enable the development of materials systems that are self- monitoring and allow for communication with external environments. Here, we report a general strategy for preparing ordered 3D interconnected and addressable macroporous nanoelectronic networks from ordered two-dimensional (2D) nanowire nanoelectronic “precursors”, which are fabricated by conventional lithography. The 3D networks have porosities larger than 99%, contain ca. 100’s of addressable nanowire devices, and have feature sizes from the 10 micron scale (for electrical and structural interconnections) to the 10 nanometer scale (for device elements). The macroporous nanoelectronic networks were merged with organic gels and polymers to form hybrid materials in which the basic physical and chemical properties of the host were not substantially altered, and electrical measurements further show a > 90% yield of active devices in the hybrid materials. The positions of the nanowire devices were located within 3D hybrid materials with ca. 14 nm resolution through simultaneous nanowire device photocurrent/confocal microscopy imaging measurements. In addition...

Biomimetics through nanoelectronics: development of three-dimensional macroporous nanoelectronics for building smart materials, cyborg tissues and injectable biomedical electronics.

Liu, Jia
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation
EN_US
Relevância na Pesquisa
56.2%
Nanoscale materials enable unique opportunities at the interface between physical and life sciences. The interface between nanoelectronic devices and biological systems makes possible communication between these two diverse systems at the length scale relevant to biological functions. The development of a bottom-up paradigm allows the nanoelectronic units to be synthesized and patterned on unconventional substrates. In this thesis, I will focus on the development of three-dimensional (3D) nanoelectronics, which mimics the structure of porous biomaterials to explore new methods for seamless integration of electronics with other materials, with a special focus on biological tissue.; Chemistry and Chemical Biology

Modelagem e avaliação numérica de absorvedores dinâmicos de vibrações sintonizáveis baseados em ligas com memória de forma; Numerical modelling and assessment of tunable dynamic vibration absorbers based on shape memory alloys

Paulo Júnior, Wellington Luziano
Fonte: Universidade Federal de Uberlândia Publicador: Universidade Federal de Uberlândia
Tipo: Dissertação
POR
Relevância na Pesquisa
46.16%
No contexto dos chamados materiais inteligentes, as ligas com memória de forma (Shape Memory Alloys – SMA) vêm sendo intensivamente investigadas com vistas a aplicações em diversos tipos de sistemas de engenharia e em problemas interdisciplinares. Especificamente, as SMA têm sido utilizadas para a mitigação de vibrações mecânicas, graças ao chamado efeito pseudoelástico, responsável pela ocorrência de histerese. Outra característica relevante desses materiais é a coexistência de duas fases cristalográficas (martensita e austenita), com propriedades mecânicas distintas, cujas frações relativas dependem da temperatura e da tensão. No presente trabalho, esta última característica é explorada em associação com uma estratégia de controle passivo de vibrações, baseada nos chamados absorvedores dinâmicos de vibrações sintonizáveis (ADV), que são dispositivos conectados à estrutura vibratória, cuja rigidez e/ou inércia podem ser ajustados em conformidade com a frequência de excitação, de modo que a vibração da estrutura seja altenuada. Especificamente, explora-se a possibilidade de confecção de ADVs sintonizáveis cuja rigidez pode ser ajustada por meio de variações controladas da fração relativa martensita/austenita induzidas por alterações da temperatura. Por meio de simulações numéricas...

Smart material using fiber Bragg grating transducers and shape memory alloy actuators

Rodríguez Cobo, Luis; Quintela Incera, Antonio; Cobo García, Adolfo; López Higuera, José Miguel
Fonte: SPIE Society of Photo-Optical Instrumentation Engineers Publicador: SPIE Society of Photo-Optical Instrumentation Engineers
Tipo: info:eu-repo/semantics/conferenceObject; publishedVersion
ENG
Relevância na Pesquisa
46.19%
A structure based on a smart material and a PID control loop is presented in this paper. A glass fiber reinforced plastic material is instrumented with Fiber Bragg Gratings (FBG) and Shape Memory Alloy (SMA) actuators. The smart material and the smart structure are both successfully checked by being subjected to different operational conditions at the laboratory. Very good responses are obtained under both slow and quicker varying conditions.

Vibration Reduction for Flexible Spacecraft Attitude Control Using PWPF Modulator and Smart Structures

Song, G.; Agrawal, B.N.
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Relevância na Pesquisa
36.46%
The article of record as published may be found at http://dx.doi.org/10.1109/AERO.1999.793157; This paper presents a new approach to vibration reduction of flexible spacecraft during attitude control by using Pulse Width Pulse Frequency (PWPF) Modulator for thruster firing and smart materials for active vibration suppression. The experiment was conducted on the Naval Postgraduate School (NPS)'s Flexible Spacecraft Simulator (FSS), which consists of a central rigid body and an L-shape flexible appendage. A pair of on-off thrusters are used to reorient the FSS. To actively suppress vibrations introduced to the flexible appendage, embedded piezoelectric ceramic patches are used as both sensors and actuators to detect and counter react to the induced vibration. For active vibration suppression using the piezoelectric ceramic patches, Positive Position Feedback (PPF) control targeting at the first two flexible modes of the FSS system is used. Experimental results demonstrate the effectiveness of the control strategy of PWPF modulation for attitude control and PPF for active vibration suppression. This paper presents a new approach to vibration reduction of flexible spacecraft during attitude control by using Pulse Width Pulse Frequency (PWPF) Modulator for thruster firing and smart materials for active vibration suppression. The experiment was conducted on the Naval Postgraduate School (NPS)'s Flexible Spacecraft Simulator (FSS)...

Dynamic response of structures constructed from smart materials

Caughey, T. K.
Fonte: Instituto de Tecnologia da Califórnia Publicador: Instituto de Tecnologia da Califórnia
Tipo: Article; PeerReviewed Formato: application/pdf
Publicado em /03/1995
Relevância na Pesquisa
46.16%
The dynamic analysis of structures constructed of homogeneous smart materials is greatly simplified by the observation that the eigenfunctions of such structures are identical to those of the same structures constructed entirely of purely elastic materials. The dynamic analysis of such structures is thus reduced to the analysis of the temporal behaviour of the eigenmodes of the structure. The theory is illustrated for both continuous and discrete structures using the generalization of 'positive position feedback' to distributed control.

"Smart" Behavior of Non-Canonical Elastin-Like Polypeptides

Garcia Quiroz, Felipe
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Tese de Doutorado
Publicado em //2011
Relevância na Pesquisa
46.34%

Despite decades of research since the discovery of the environmental sensitivity of tropoelastin, only a handful of elastin-inspired polypeptides departing from the canonical VPGXG motif, where X is any amino acid except proline, have been uncovered. Hence, the field of "smart" protein-polymers has evolved mainly through the introduction of innovative molecular architectures. Instead, we decided to explore sequence diversity as a necessary tool to broaden the biomedical and biotechnological utility of these "smart" protein-polymers. Using a new, highly parallel method for the synthesis of repetitive genes, we conducted a systematic study of the sequence constraints of the canonical VPGXG motif by substituting or inserting Alanine residues along this pentapeptide motif, which yielded new pentapeptide and hexapeptide, non-canonical ELP motifs. These studies led to the discovery of new families of hexapeptide motifs with fully reversible phase transition behavior and suggested an unexpected degree of sequence and conformational promiscuity in the canonical motif that hints at the existence a large space of amino acid sequences with intrinsic "smart" behavior. Moreover, this work shed light into the conformational requirements of the phase transition behavior and suggested the possibility to control the assembly of "smart" protein-polymers in a sequence-controlled manner.

; Thesis

Material selection for the actuator design for a biomimetic rolling robot conducive to miniaturization

Dotson, Zachary S.
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
46.1%
The purpose of this thesis was to research, select, and test an actuator mechanism for ultimate use on a centimeter scale biomimetic rolling robot. The design of the actuator will allow a rolling motion that closely mimics cellular locomotion in addition to providing a novel motion for other applications. The basis of the design has been completed through previous mechanical design research. The existing robotic mechanism consists of a larger scale spherical body with legs which controllably extend and contract, yielding a trajectory which results in a rolling motion of the body. The previous research also derived a mathematical model of the kinematics of the motion. The current work seeks to improve on the previous work by selecting an actuation mechanism that preserves the biomimetic motion and that allows this device to eventually be utilized at the microscale. Material selection is of critical importance in developing actuation mechanisms at the microscale. Smart materials were extensively researched because of their actuation properties. Based on the strain percentage, power requirement, and force output, it was determined that the preferable actuation material was an electroactive polymer (EAP). Samples of Ionic Polymer-Metal Composite (IPMC)...

A concise review of the applications of NiTi shape-memory alloys in composite materials

Sanusi,Kazeem O.; Ayodele,Olukayode L.; Khan,Mohamed T.E.
Fonte: South African Journal of Science Publicador: South African Journal of Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2014 EN
Relevância na Pesquisa
46.24%
Composite materials have increasingly been used in construction and in the aerospace and automotive industries because they are lightweight, strong and corrosion resistant, and because their anisotropic properties can be controlled; maintenance costs are also low. However, there is a growing demand for improved composite materials which have 'smart' capabilities, that is, they are able to sense, actuate and respond to the surrounding environment. Shape-memory alloys (SMAs) possess sensing and actuating functions. Embedding SMAs into composite materials can create smart or intelligent composites. Amongst the commercially available SMAs, NiTi alloys - in the form of wires, ribbons or particles - are the most widely used because of their excellent mechanical properties and shape-memory performance. These materials have found application in broad fields of engineering and science as a result of their superior thermomechanical properties. Here we review the use of NiTi SMAs in applications such as vibration control, shape control, position control and adaptive stiffening.