Recent Patents on Nanotechnology - Volume 3, Issue 1, 2009

Dr. Sergei S. Berdonosov was born in 1939 in Moscow, Russia. As a result of his studies, he got a gold medal at school in 1956 and an excellence diploma at the Moscow State University in 1961. His Ph.D. thesis, defended in 1964, was dedicated to zirconium, hafnium, niobium, tantalum, and protactinium bromides, and a Dr. Sci. thesis (2002) was devoted to the radiochemical studies of desublimation and new approaches to determination of physico-chemical properties of substances and materials. Dr. Berdonosov has been working all his post-student life in the Department of Radiochemistry (Faculty of Chemistry, Moscow State University, Russia). He is a professional radiochemist; additionally, his research interests include inorganic chemistry in whole, physical chemistry, nanotechnology, and chemical education. It is possible to affirm that the last activities are the most favorite type of dedication. Dr. Berdonosov works on the Chemistry Department more than 35 years and more than 25 years teaches chemistry at 171st School in special groups of school students who wish to enter further in Department of Chemistry. During these years, under his management in this school, Prof. Berdonosov has learned taught bases of chemistry more than 1500 school students. At present, he has a certificate of a “chemist teacher of the highest category”. More than 500 students of the Department of Radiochemistry were his students, including ourselves. He was a director of 6 Ph.D. and 20 M.Sc. thesis; one of them was awarded in 2001 with very prestigious gold medal of Russian Academy of Sciences. He made a great contribution to the development of education of radiochemistry and radioecology in high-education institutes. Dr. Berdonosov has written more than well-known 20 textbooks for universities and schools and belongs to the Editorial Board of the Journal “Chemistry at School”. In 1995-1998 he took more than 100 lectures for teachers in distinct regions of Russia and earlier abroad (La Habana (1969), Belgrad (1979), Sofia (1985)). He was and continues being editor and author of a series of articles for main Soviet and Russian encyclopedias. In 2001-2005 he was awarded by a series of grants of Moscow Government. Leading research activities of Prof. Berdonosov resulted well-known achievements, which formed the base of new technologies, awarded by various prizes at national level (1976, 1981, 1986), in particular the most famous in the former USSR State Prize (1989) and Lomonosov Prize (2003). Really, he started to work in nanotechnology area in the time, when this term did not formally exist: it was a part of physical chemistry, physics and chemistry of materials. One of his favorite research fields is obtaining hollow micro- and nanoparticles of a series of inorganic compounds and further use of them for creation of materials possessing special properties. His leading studies of kinetics of physico-chemical processes resulted obtaining new materials with special properties. Recently, Dr. Berdonosov and his colleagues discovered a series of new phenomena, at present they continue working in these areas. Prof. Berdonosov has published more than 150 original research works in Russian national and international journals and 4 patents. We congratulate Prof. Berdonosov on the occasion of his 70th anniversary and wish him long and fruitful life and further scientific and educational achievements.

Silicon nanowires (SiNWs) have been demonstrated as one of the promising building blocks for future nanodevcies such as field effect transistors, solar cells, sensors and lithium battery; much progress has been made in this field during last decades. In this review paper, the synthesis and physical properties of SiNWs are introduced briefly. Significant advances of SiNWs-related nanodevices reported in recent literature and registered patents are reviewed. The latest development and prospects of SiNWs-related nanodevices are also discussed.

Surface-enhanced Raman scattering (SERS) is recognized as one of the most sensitive spectroscopic tools offering highly sensitive chemical and biological detection. The fact that particle plasmon allows direct coupling of light to resonant electron plasmon oscillation has spurred tremendous efforts in the design and fabrication of highly SERSactive substrates in nanostructured films and metallic nanoparticles. Theoretical studies have shown that symmetry breaking allows for more complex plasmon propagation, potentially leading to more intense electromagnetic field generation along the structure and in gaps formed between these materials. Anisotropic metallic nanostructures have all of the characteristics that make them excellent candidates as SERS substrates. Thus, SERS is expected from anisotropic materials. This review focuses on the progress and advances in the design and fabrication of anisotropic nanostructures for SERS, with an emphasis on future challenges.

Electrospinning has been recognized as a feasible process for fabrication of continuous fibers with diameters ranging from several micrometers down to a few nanometers. This article presents an overview of recent progress in functional polymeric nanofibers prepared by electrospinnning. Except of functional nanofibers fabricated from electrospinning of functional polymers, nanofibers from a combined technology such as coaxial electrospinning, electrospinning with living radical polymerization, and electrospinning with surface modification, would also be introduced in this review. Furthermore, the functionality and application of nanofibers would also be highlighted.

Intensive research focuses on the development of nanoparticles, not only for their fundamental scientific interest, but also for a variety of technological applications. Monodisperse nanoparticles with a size variation of less than 5% exceptionally have been received much attention, due to their novel and high performance induced by the strong dependence of properties upon the dimension of the nanoparticles. Their unique properties result in a great of potential applications in the area of ultra-high density magnetic storage media, electronics, biomedical usage, medical diagnosis, catalyst, etc. This is stimulating a high level of interest in the development of large scale synthesis techniques of monodisperse nanoparticles. In this article, the recent advance about the relevant aspects of large scale synthesis approaches for various monodisperse nanoparticles was summarized.

Ferroelectric oxide materials with a perovskite structure have promising applications in electronic devices such as random access memories, sensors, actuators, infrared detectors, and so on. Recent advances in science and technology of ferroelectrics have resulted in the feature sizes of ferroelectric-based electronic devices entering into nanoscale dimensions. At nanoscale perovskite ferroelectric materials exhibit a pronounced size effect manifesting itself in a significant deviation of the properties of low-dimensional structures from the bulk and film counterparts. One-dimensional perovskite ferroelectric nanotube/nanowire systems, offer fundamental scientific opportunities for investigating the intrinsic size effects in ferroelectrics. In the past several years, much progress has been made both in fabrication and physical property testing of perovskite ferroelectric nanostructures. In the first part of this paper, the recent patents and literatures for fabricating ferroelectric nanowires, nanorods, nanotubes, and nanorings with promising features, are reviewed. The second part deals with the recent advances on the physical property testing of perovskite ferroelectric nanostructures. The third part summarizes the recently patents and literatures about the microstructural characterizations of perovskite ferroelectric nanostructures, to improve their crystalline quality, morphology and uniformity. Finally, we conclude this review with personal perspectives towards the potential future developments of perovskite ferroelectric nanostructures.

A review is given about the current state-of-the-art surrounding micro/nano scale welding/joining used in miniaturization or microsystems. Except for reviewing the applications of micro/nano welding/joining in various fields, such as microelectromechanical system (MEMS), micro total-analysis systems (μTAS), carbon nanotubes (CNTs) etc., the optimal equipments for micro/nano welding/joining, its corresponding future applications and research directions are discussed. Moreover, an extensive part of the paper is devoted to the introduction of new techniques, micro/nano laser and electron beam welding/joining. In turn, it is anticipated these techniques will be used in future micro/nano welding/joining applications. Meanwhile, because even smallest particles of dust can influence the results, more considerations are given to machine improvements that are required for its corresponding nano welding/joining. It will be one challenge for R&D efforts to combine the progress in micro/nano scales with that in miniaturization. This review provides a timely explanation of the literature surrounding the factors required for successful micro and nano welding/joining.

The paper discuses the design of 1-bit full adder circuit using Shannon theorem. This proposed full adder circuit is used as one of the circuit component for implementation of Non- Restoring and Restoring divider circuits. The proposed adder and divider schematics are designed by using DSCH2 CAD tool and their layouts are generated by Microwind 3 VLSI CAD tool. The divider circuits are designed by using standard CMOS 0.35μm feature size and corresponding power supply 3.5 V. The parameters analyses are carried out by BSIM 4 analysis. We have compared the simulated results of the Shannon based divider circuit with CPL and CMOS adder cell based divider circuits. We have further compared the results with published results and observed that the proposed adder cell based divider circuit dissipates lower power, gives faster response, lower latency, low EPI and high throughput.

Fatigue-free Bi3.2Sm0.8Ti3O12 ferroelectric thin films were prepared on p-Si(100) substrate using a sol-gel deposition process. The formation and orientation of thin films were studied upon annealing conditions with XRD and SEM. Experiment results indicate that after preannealing at 400°C for 10 min, annealing at 700°C resulted in formation of strong a-axis oriented films. The orientation degree, I(200)/I(117), remarkably increases from 1.033 to 1.76 and 6.49 with increasing annealing time from 3 to 10 and 15 min respectively. However, only (117)-oriented films were produced by annealing films at 900°C for 3 min without the preannealing.

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