Recently, organic-inorganic hybrid nanocomposite materials have been of great interest for their extraordinary performances due to the combination of the advantageous properties of polymers and the size dependent properties of nanocrystals (NCs). Interaction between the polymer matrix and nanocrystalline fillers produces wonderful features, viz. thermal, magnetic, mechanical, electrical and optical properties to these materials. Modern applications require a new design of responsive functional coatings which is capable of changing their properties in a controlled way. However, the synthesis of Ⅱ-Ⅵ nanoparticles into the polymer matrix of its nanocomposites with adjustable sizes and protected from photo-oxidation is a big challenge to the scientific community. It is difficult to synthesize the highly enhanced luminescence in polymers and its semiconductor nanocomposite systems. Luminescence from the polymer embedded Ⅱ-Ⅵ nanoparticles is greatly enhanced and better stability can be achieved from the composite compared to bulk materials. The formation of nanocomposites can be confirmed by photoluminescence (PL) spectroscopy. It is an important technique for determining the optical gap, purity, crystalline quality defects and analysis of the quantum confinement in these nanocomposite materials. In this paper, we have reviewed the present status of Ⅱ-Ⅵ polymer nanocomposites from the photoluminescence studies point of view. We have also shown the results of the PL of these nanocomposite materials and the results will be compared with the reported literature by other groups.

关键词：纳米复合材料；半导体；聚合物；光致发光

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Nanofluids are not only valuable for their enhanced thermal properties - a large international research effort has been directed towards developing nanoparticles and nanofluids with tunable optical properties. Optical sensors, optical filters, solar absorbers, lasers, cancer therapies, and a whole suite of other applications can benefit from nanofluids with controlled optical properties. While there are many solid optical components commercially available, flowing fluid-based (both liquids and gases) systems are superior for transient applications. Optical engineering of nanofluids has been made possible by recent advances in fabrication techniques - enabling tight tolerance, highly reliable production of almost any material in a wide variety of shapes and sizes. In the right dose, the addition of well-designed nanoparticles can alter the optical properties of pure fluids (water, oils, and alcohols) from being transparent to bespoke fluids which are highly absorbing, scattering, or a mixture for any portion of the optical spectrum. Metallic nanoparticles, in particular, display the highly selective phenomenon of plasmon resonance which allows them to be utilized to create fluids which can interact strongly with a small band of light. Thus, the development of a new class of nanofluid-based optofluidic devices represents an emerging trans-disciplinary synthesis between nanotechnology, thermofluids, and optics. As a primer to this field and to encourage research activity in this area, this chapter will describe the state-of-the-art and the requisite theory behind this type of technology.

关键词：纳米流体；光学工程；增强热性能

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Magnetic nanofluids are suspensions of nanometer sized magnetic particles stabilized aginst agglomeration and sedimentation. The uniqueness of magnetic nanofluid is that its properties and the location can be easily controlled by an external magnetic field, which is being exploited for many scientific, industrial, and commercial applications. During the search for superior coolants with better heat transfer efficiencies, it was found that magnetic nanofluids can produce a dramatic thermal conductivity enhancement (＞ 300%) due to the efficient transport of heat through the percolating nanoparticle paths. It has also been demonstrated that the field-induced thermal conductivity enhancement can be precisely and reversibly tuned from a low to very high value by varying the magnetic field strength and its orientation. Since the application of magnetic field enhances not only the thermal conductivity but also the rheological properties of the magnetic nanofluid, they find applications in smart cooling cum damping devices. This chapter summarizes the recent research on thermal conductivity of magnetic nanofluids. The effects of volume fraction, magnetic field strength, nanoparticle size, temperature, base fluid material, aggregation and additives on thermal conductivity of magnetic nanofluids are discussed in detail.

关键词：磁性纳米流体；悬浮液；热导率

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In composites, two or more materials are combined in order to employ their individual virtues while minimizing their deficiencies. In general, these hybrid systems exhibit new chemico-physical characteristics that originate from the cooperative effect of the distinctive properties of the materials used. In its own particular way, the engineering of composite carbon-based materials through decoration with metal NanoParticles (NPs) has proved to be key for the improvement of the intrinsic properties of graphene and Carbon NanoTubes (CNTs). A plethora of methods have been employed for the controlled deposition and immobilization of metal NPs onto the CNT surface. To this end, both physical and chemical approaches have been recently developed; each offering its own strengths and weaknesses, which can then be tailored for specific applications. Here we start with an overview of the main methods used for the synthesis of these hybrid systems, with emphasis on the most meaningful examples described in the literature. Metal NP-CNT composites are highly suitable for a number of practical applications ranging from catalysis to optoelectronics to chemical and bio-sensing. The Chapter reports the main efforts carried out to date to integrate metal NP-CNT composites in high-performance nano-devices. The use of modified CNTs often proved more effective than that of pristine ones; however in some cases decoration with metal NPs leads to no improvement. This Chapter sets out to describe the mechanisms, which improve decorated CNTs or pristine CNTs according to the case involved. We conclude by considering metal filled-CNTs, a special class of metal modified-CNTs. The different approaches to filling CNTs with metal NPs are discussed; we then focus on their use as magnetic probes and microwave absorbing materials.

关键词：金属纳米粒子；碳纳米管复合材料；控制器

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Optical metamaterials are man-made composite materials constructed with nanometer-sized periodic structures containing both dielectric and metal materials. These structures can produce materials with negative index of refraction-a unique material property that does not occur naturally. The theoretical breakthroughs made in this new class of electromagnetic materials are closely linked with progress in developing physics-driven design, novel fabrication, and characterization methods. For the optical waveguiding, a perfect control of the interaction between light and matter has been brought closer by the advances in fabrication of optical metamaterials. The unusual electromagnetic properties of metamaterials are expected to enable a new generation of miniaturized passive and active optical devices based on novel optical waveguides. In developing design strategies and new concepts for such devices, it is paramount that anisotropic properties of metamaterials are considered along with their other material features. Moreover, even the ways in which common devices operate require revisions when ordinary materials in their design are replaced by anisotropic metamaterials. Therefore, these metamaterials provide a route to creating potential devices through artificially engineered structures with negative average relative permittivity and permeability. The electromagnetic response of a metamaterial can be designed to produce desired waveguide properties. One particularly interesting metamaterial device is planar metamaterial waveguide structure that has potentially exciting applications. Properties of metamaterial waveguides when the limitations arise from fabrication techniques and physical principles have been taken into account. A considerable amount of theoretical effort has also been devoted to the analysis of optical propagation through different types of metamaterial structures, including uniaxial dielectrics and indefinite media, metal-dielectric heterostructures and superlattices, as well as strongly anisotropic waveguides. This chapter will give a brief review about perspective and prospective of the metamaterial optical waveguides.

关键词：超材料光波导；光学超材料；纳米尺寸

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Constitutive equations of irreversible deformation, e.g. elastoplastic, viscoelastic and viscoplastic deformations are described in rate forms in which the stress rate and the strain rate are related to each other through the tangent modulus. Therefore, numerical calculations are executed in their incremental forms by the input of load (stress) increment or displacement (deformation) increment, while the time increment is also input in rate-(or time-)dependent constitutive equations, e.g. viscoelastic and viscoplastic ones. The algorithm to pull-back the stress to the yield surface is required for the numerical calculation by the elastoplastic constitutive equations other than the subloading surface model possessing the automatic-controlling function to attract the stress to the yield surface. Numerical calculation by the explicit (or forward Euler) method results in the deviation from the exact solution or fails without convergence in the case that the tangent modulus is not constant, if an incremental step is taken large.

关键词：本构方程弹塑性；切线模量；粘弹性

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Spintronics is the advanced branch of nanoelectronics making use of specially engineered materials that can impart spin functionality in the electrons, in addition to its well-known property of charge. Spin field effect transistor (spin-FET) is a spin-device consisting of ferromagnetic source and drain electrodes to impart spin-functionality into the device with the spin field effect transistor action realized with an electric field applied through the gate voltage. The whole concept relies on controlling the spin precession from source to the drain through a spin-conducting channel by applying a voltage on the gate region. An interesting class of materials is the half-metallic ferromagnetic compounds having majority spin density of states at the Fermi level (E_F) showing metallic behaviour, while minority spin density of states at a certain gap below the E_F. CrO_2 is such a half-metallic oxide with theoretical predicted 100% degree of spin-polarization and high Curie temperature (T_C) of ～395 K making it appropriate for spin-device applications. Hence, nanotechnology is the technology of the future, giving rise to the design of new kinds of materials (electronic & magnetic) and devices based on them, all set to revolutionize the world.

关键词：自旋电子学；纳米技术；自旋电子学；自旋金属氧化物

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Biometrics authentication is a process by which an individual’s identity is authenticated by evaluating one or more unique biological traits, such as voice recognition, palm geometry, DNA identification, gait recognition, fingerprint matching, facial recognition, iris recognition, signature verification, and vein recognition. It was introduced based on the behavioral and physiological characteristics of an individual, which is difficult to be duplicated. Considered to be more reliable compared to physical devices and numeric codes, biometrics involves verification and identification processes to authenticate an individual. Verification is a one-to-one matching process that is used to verify the biometrics traits of an individual against a particular template in a database.

关键词：生物特征认证；身份认证过程；行为；生理特点；物理设备；数据库；生物测量特征

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UCB is the blood that remains in the placenta and the attached umbilical cord after childbirth. Cord blood contains stem cells that are unique, smart, and capable of treating several lifethreatening diseases. They are used in the treatment of hematopoietic and genetic disorders. The placental blood can produce ten times more stem cells compared to the umbilical cord, which can in turn be used for the treatment of an adult patient. The cord blood, which is collected during childbirth, is stored and cryopreserved. The cord blood can be stored at private cord blood banks or public cord blood banks. This preserved blood can be used for transplantation and the treatment of diseases at the later stages of life.

关键词：干细胞脐血；胎盘；附脐带血液；造血细胞；遗传性疾病；移植；治疗疾病

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Bio-implants are medical devices made up of biomaterials used for the repair, replacement, and augmentation of damaged tissues, particularly for the treatment of orthopedic and cardiovascular conditions. Orthopedic bio-implants are used in replacement procedures for the hip, spine, knee, and other extremities such as the shoulder, wrist, elbow, and ankle. Cardiovascular bio-implants include CRM devices, stents, and prosthetic heart valves.

关键词：生物植入物；修复；生物材料；医疗装置；整形外科；心血管疾病；矫形生物植入物

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