Lead based ferroelectric ceramics including lead titanate (PT) and lead zirconate titanate (PZT) are well known for their ferroelectric as well as piezoelectric properties and are being used extensively for sensor and actuator applications [1]. However, considering the toxicity of lead and its compounds, there is a general awareness for the development of environmental friendly lead-free materials. So many alternate lead-free compositions based on barium titanate, alkaline niobates, bismuth perovskites, and bismuth layered structured ferroelectrics (BLSFs) are being investigated [2-6].Recently there is a lot interest in the Aurivillius-type lead-free bismuth layer-structured ferroelectric (BLSFs) materials due to their low dielectric constant, high transition temperatures, fatigue-free properties, anisotropy in the electromechanical coupling factors, and their excellent temperature stability for fine tolerance resonator applications [7,8]. Since the bismuth layer structured ferroelectric play an important role for electric applications, its structural and material properties are wide...
Thermal methods of analysis have been in use for quite a long time. Their application in the analysis of pharmaceutical materials has made it possible for pharmacists and researchers to understand their contents and characteristics. However, thermal methods have several disadvantages that have led researchers to opt for nano-thermal methods of analysis. Nano-thermal analysis methods use special resolution imaging potential that is enhanced by the availability of atomic force microscopy and thermal analysis methods.
Some ceramics are used in orthopaedic applications such as bone repair, bone augmentation and joint replacement but their use in this field is not as extensive or widespread as metals and polymers because ceramics have poor fracture toughness. This severely limits the use of ceramics in load bearing applications (Davis, 2003).
Leads chemical properties are that it dissolves slowly in water, it doesn’t react with oxygen in the air, it doesn’t burn and it reacts quickly with hot acids but it reacts slowly to cold ones. It is resistant to corrosion but it tarnishes when it is exposed to air and it is toxic
The materials with perovskite structure have numerous studies in last decade. Their structure, electrical and magnetic properties has been established up to a great extent. However, a detail study relating to double perovskite type of materials is still lacking in the literatures. In this report an effort is made to study in detail the behaviour of few double perovskite materials and then compared with their perovskite counterpart specifically their structure, morphology and electrical behaviour. These short of studies will provide a base line to select these materials for technological applications.
Lead has many different physical and chemical properties. Being a solid at room temperature, lead is the heaviest member of the carbon family (1). Lead can by physically described as a soft metallic gray color, and tends to be formed naturally with jagged edges. It is also a very ductile and malleable element. When exposed, rust tends to form on the surfaces of lead. Being a softer element, Lead can be easily bended, cut, pulled and changed (2). Compared to other elements, when used to conduct electricity lead does very poorly. Lead also has many Chemical properties. Lead has very few chemical properties. Lead does not burn, dissolves very slowly in cold water/ cold acid, and slightly faster in warm acid (1).
The cotunnite-type phase was claimed by L. Dubrovinsky and co-authors to be the hardest known oxide with the Vickers hardness of 38 GPa and thebulk modulus of 431 GPa (i.e. close to diamond's value of 446 GPa) at atmospheric pressure.However, later studies came to different conclusions with much lower values for both the hardness (7–20 GPa, which makes it softer than common oxides like corundum Al2O3 and rutile TiO2) and bulk modulus (~300 GPa).
such as Sr, Ba, and Pb or a mixture of these [12]. Barium hexaferrites (BaFe12O19) with a magnetoplumbite structure are well known as hard magnetic materials which are based on iron oxides. Hexagonal ferrites are referred to as hard because the direction of magnetization cannot be changed easily to another axis [].Barium ferrite possesses relatively high Curie temperature,
Neidig, H. A., and J. N. Spencer. "Precipitating Lead Chromate on a Small Scale." General Chemistry For Engineering And Science. Mason: Cengage Learning, 2012. 83-90. Print. Signature Lab Ser.
quartz. When temperature is set to more than 980K, α-FePO4 is shown as α-β transition, while the successive
Graphene has received great mass media coverage since Geim and Novoselov published their foundlings about monocrystalline graphitic films in 2004, which won them the Nobel Prize in Physics in 2010. (Novoselov et al, 2004) It has been described as the wonder substance or super material by the mass media, not only because it is the thinnest material ever known and the strongest ever measured, but also due to its excellent electrical, thermal, mechanical, electronic, and optical properties. It has high specific surface area, high chemical stability, high optical transmittance, high elasticity, high porosity, tunable band gap, and ease of chemical functionalization which helps in tuning its properties (Geim et al, 2007) Moreover, graphene has a multitude of amazing properties such as half-integer room-temperature quantum Hall effect (Novoselov et al, 2007), long-range ballistic transport with almost ten times greater electron mobility than that of silicon, and availability of charge carriers that behave as massless relativistic quasi particle, known as Dirac fermions. (Geim et al, 2007) The outstanding electrical conductivity and the transparency and flexibility of graphene-based material have led to research and development of some future technologies, such as flexible and wearable electronics. In addition, graphene can also be used for efficient energy storage materials, polymer composites, and transparent electrodes. (Geim et al, 2007) This paper presents a
The unique set of elements known as the alkaline earth metals are key components to humanity and life as we know it. Without them, many things that we both love and need would be gone. These remarkably diverse yet very similar elements that make up the alkaline earth metals family are: Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), and Radium (Ra). Although this family is often overshadowed by the infamous alkali metals, you will soon learn how spectacular and brilliant these metals really are and their value to human life.
The elongations-to-break of aged PHB and PHBV at 15°C decreased by 64% and 72%, respectively, after 168 days (Srubar et al., 2012). Ultimate strengths decreased by 28% and 8.9% for PHB and PHBV, respectively. During the aging process, the amorphous regions of PHB and PHBV underwent glassy aging in the rigid amorphous fraction, resulting a significant embrittlement. Over the testing period, PHB and PHBV samples had a maximum increase in modulus of 166% and 178%, and crystallinity of approximately 41% and 58%, respectively (Srubar et al.,
The main purpose of green nanotechnology has been to develop clean technologies that would minimize potential human and environmental health risk. Also, to encourage replacement of existing products with the clean technologies that is more environmentally friendly. There are many benefits of using green nanotechnologies as the new solution for energy in both their current availability and their current development. Over the new few decades, the highest growth opportunities will come from application of nanomaterials for making better use of existing resources. Nanotechnologies will help reduce weight of carbon emission in transportation utilizing nanocomposite materials that quickly diffuses across the automotive and aerospace industries. Applications of nanotechnologies will result in a global annual savings of 8000 tons of carbon dioxide, which will rise even further to over millions tons by 2020. But, let’s focus on the positive effects of Green Nanotechnology in Solar.
Lead is a commonly used chemical element, it is a heavy metal but yet denser than most materials we use. On the periotic table lead is assigned under the symbol Pb (Plumbum, meaning liquid silver) and the atomic number of lead is 82. Lead was never formally discovered; it has been around since the ancient times. The color of led color at first comes off as a blue/whitish color when freshly cut and once it is exposed
Most dielectric materials are solid. Examples include porcelain (ceramic), mica, glass, plastics, and the oxides of various metals. Some liquids and gases can serve as good dielectric materials. Dry air is an excellent dielectric, and is used in variable capacitors and some types of transmission lines. Distilled water is a fair dielectric. A vacuum is an exceptionally efficient dielectric.