Er5Si4 is a member of the R5(Si4−xGex) family of alloys, where R=rare earth metal. Many of these compounds display a strong coupling between the magnetic and crystal lattices. In the naturally layered R5(Si4−xGex) mat...
详细信息
Er5Si4 is a member of the R5(Si4−xGex) family of alloys, where R=rare earth metal. Many of these compounds display a strong coupling between the magnetic and crystal lattices. In the naturally layered R5(Si4−xGex) materials, inter- and intralayer interactions can be controlled by chemical and physical means; thus their physical properties can be tailored within wide limits. The Er5Si4 is unique in that the temperature dependent structural sequence is opposite that of other representatives of this family. The magnetism of Er5Si4 is reflective of its exceptional place within the series.
We examined liquid crystalline phases of the cytoskeletal polyelectrolyte filamentous (F-)actin in the presence of multivalent counterions. As a function of increasing ion concentration, the F-actin rods in either an ...
详细信息
We examined liquid crystalline phases of the cytoskeletal polyelectrolyte filamentous (F-)actin in the presence of multivalent counterions. As a function of increasing ion concentration, the F-actin rods in either an isotropic or a nematic phase will transform into a new and unexpected lamellar phase of cross-linked rafts (LXR phase), before condensing into a bundled phase of parallel, close-packed rods. This behavior is generic for alkali earth divalent ions Mg2+, Ca2+, Sr2+, and Ba2+, and the structural transitions are achieved without any architecture-specific actin-binding linker proteins.
Recent developments in nanosciences and nanotechnology have created tremendous enthusiasm among researchers and scientists across the globe. The rapidly increasing interest among various engineering disciplines toward...
详细信息
Recent developments in nanosciences and nanotechnology have created tremendous enthusiasm among researchers and scientists across the globe. The rapidly increasing interest among various engineering disciplines toward research and development needs of nano-domain have spurred the growth in areas such as nanoelectronics, biotechnology & health delivery system and commerce in general. In this paper, a state-of-the-art encompassing the recent developments and the key problems in nanomanufacturing that relate to the domain are presented. Furthermore, contribution in this field from the researchers in different parts of the world are included and compared to monitor the present progress. With the down sizing of present silicon, IC technology, validity of Moore's law has become seemingly limited. However, it is strongly believed that the novel materials will provide the answer for further scaling of device density and performance. For example, most recent attention has been paid on carbon nanotubes, which can be used in nanosize electronic devices. It is still a question whether nanotube based technology will actually contribute to the existing CMOS technology or it is a totally new device architecture from CMOS technology. Besides, it is unclear whether this material will meet scalability, durability and existing performance. Modelling and simulation is a vital element for gaining insight to the behaviour of these materials and also to the characterization process. A part of this paper will be devoted to fully analyze the current trends in nanoelectronics based on nanostructured materials other than silicon.
The effects of various sputtering gases (Ar, Kr and Xe) on the roughness, coverage, stress, density, and nanomechanical properties of CNx thin films were studied. The CNx was deposited on Si(100) substrates using dc m...
详细信息
The effects of various sputtering gases (Ar, Kr and Xe) on the roughness, coverage, stress, density, and nanomechanical properties of CNx thin films were studied. The CNx was deposited on Si(100) substrates using dc magnetron sputtering and by using atomic force microscopy a three-parameter roughness analysis was done. It was found that a 3-nm-thick dc-sputtered CNx overcoat displaying good coverage was obtained using Kr and Xe.
An on-chip spectrophotometer system, consisting of a CMOS focal-plane-array and polydimethylsiloxane (PDMS) microfluidic flow channels, is described. One of the potential applications of this prototype system is to pe...
详细信息
An on-chip spectrophotometer system, consisting of a CMOS focal-plane-array and polydimethylsiloxane (PDMS) microfluidic flow channels, is described. One of the potential applications of this prototype system is to perform the enzymatic analysis of glucose, cholesterol or uric acid contained in blood.
In this paper, we study the pH response of a buried channel SOI MOSFET integrated with a nanofluidic cell. The surface of the device is exposed to solutions of different pH to validate the sensitivity of the device to...
详细信息
In this paper, we study the pH response of a buried channel SOI MOSFET integrated with a nanofluidic cell. The surface of the device is exposed to solutions of different pH to validate the sensitivity of the device to different chemical and biological environments.
Single-phase Pr5Ni1.9Si3 and PrNi were prepared and characterized by using differential thermal analysis, single crystal, and powder x-ray diffraction. Their thermal and magnetic properties were studied by measuring h...
Single-phase Pr5Ni1.9Si3 and PrNi were prepared and characterized by using differential thermal analysis, single crystal, and powder x-ray diffraction. Their thermal and magnetic properties were studied by measuring heat capacity as a function of temperature in magnetic fields up to 100 kOe and magnetization as a function of magnetic field up to 50 kOe over the temperature range from 5 to 400 K. Pr5Ni1.9Si3 orders magnetically at 50 K, and it undergoes a second transition at 25 K. As inferred from the behavior of the magnetization and magnetocaloric effect (MCE), both ferromagnetic and antiferromagnetic components are present in the magnetic ground state of the material. The heat capacity and magnetocaloric effect of PrNi confirm that it orders ferromagnetically at 19 K. Both Pr5Ni1.9Si3 and PrNi exhibit moderate magnetocaloric effects. The maximum MCE for Pr5Ni1.9Si3 is 3.4 K and it is observed at 50 K for a magnetic field change from 0 to 75 kOe. The maximum MCE for PrNi is 4.2 K, which occurs at 19 K for a magnetic field change from 0 to 100 kOe.
DNA condensation in vivo relies on electrostatic complexation with small cations or large histones. We report a synchrotron x-ray study of the phase behavior of DNA complexed with synthetic cationic dendrimers of inte...
详细信息
DNA condensation in vivo relies on electrostatic complexation with small cations or large histones. We report a synchrotron x-ray study of the phase behavior of DNA complexed with synthetic cationic dendrimers of intermediate size and charge. We encounter unexpected structural transitions between columnar mesophases with in-plane square and hexagonal symmetries, as well as liquidlike disorder. The isoelectric point is a locus of structural instability. A simple model is proposed based on competing long-range electrostatic interactions and short-range entropic adhesion by counterion release.
Computational models of austenite decomposition should provide predictions of external shape and internal microstructure as functions of time and temperature. This information may be used directly, or it can be sent t...
详细信息
ISBN:
(纸本)087339559X
Computational models of austenite decomposition should provide predictions of external shape and internal microstructure as functions of time and temperature. This information may be used directly, or it can be sent to other simulators in order to make predictions about material working properties. It is often the case that such decomposition models are constructed using kinematic information-i.e. data that relate external shape change to the internal microstructural state. These models are based on the supposition that a differential shape change can be related to a differential microstructural change given that the base state is known. This is a purely kinematic link that does not depend on the rate of decomposition. A starting point is often to estimate shape change using a weighted average of the lattice parameters of each phase present, and this is adopted in the present work. Based on a review of the literature values for lattice parameters associated with low carbon steels, an optimal set of lattice values is obtained. These thermophysical functions are then used in a new forward fitting algorithm to obtain kinetic parameters for an internal state variable model of austenite decomposition. The key idea here is that the kinetic parameters are optimized so as to match dilatometry data without the need to back out any phase fraction data prior to fitting. The model is applied to a class of industrial steels to demonstrate the accuracy of the lattice parameters and the viability of the new forward fitting methodology.
暂无评论