Das Schichtpolysilicat Kanemit wird für die Synthese des Siliciumoxids KSW-2 (siehe Bild) genutzt, das Kanäle mit quadratischem Querschnitt enthält. Dabei werden während des Auswaschens von Hexadecyltrimethylammonium-Ionen aus einem Komplex mit Kanemit die Silicatschichten von Kanemit allmählich gebogen.
To fulfill the requirements for radial or circumferential magnetizing applications, MnAlC permanent magnets with a new type of anisotropy have been developed. They were produced by a combined processing of plastic working, i.e., upsetting previously extruded billets of MnAlC permanent magnet alloys in the extrusion axis at 660°C. The direction of easy magnetization was converted into directions perpendicular to the extrusion axis by a small plastic strain induced by the upsetting. Magnetic properties in both radial and tangential directions were equivalent from a macroscopic standpoint, and were much superior to those in the axial direction. Magnetic torque measurements revealed that the direction of easy magnetization of this type of MnAlC permanent magnet lay uniformly in every direction parallel to the plane including both radial and tangential directions. The optimum magnetic properties in "the plane of easy magnetization" were as follows: Br = 4.6 kG, Hc = 2.9 kOe, iHc = 4.1 kOe and BH max = 4.1 MG.Oe. They were obtained by a nickel doped MnAlC alloy with additional tempering.
A hypothesis about (transient) colloidal stability as a controlling mechanism for particle formation in SBA-15 is presented. The hypothesis is based on results from both in situ and ex situ investigations, including cryogenic transmission electron microscopy (cryo-TEM), UV-vis spectroscopy, and dynamic light scattering (DLS). Cryo-TEM images show that particles grow via the formation of silica-Pluronic-water "flocs", which coalesce in a seemingly arbitrary manner. Despite this, the final material consists of well-defined particles with a small size distribution. We argue that the interface between the flocs and surrounding media is covered by Pluronic molecules, which provide steric stabilization. As the flocs grow, the coverage of polymers at the interface is increased until a stable size is reached, and that regulates the particle size. By targeting the characteristics of the Pluronic molecules, during the on-going synthesis, the hypothesis is tested. The results are consistent with the concept of (transient) colloidal stability.
A 4-Gb AG-AND flash memory was fabricated by using a 90-nm CMOS technology. To reduce cell size, an inversion-layer-bit-line technology was developed, enabling the elimination of both shallow trench isolations and diffusion layers from the memory cells. The inversion-layer-bit-line technology combined with a multilevel cell technique achieved a bit area 2F 2 of 0.0162μm 2 , resulting in a chip size of 126mm 2 . Both an address and temperature compensation techniques control the resistance of the inversion-layer local bit line. Source-side hot-electron injection programming with self-boosted charge, accumulated in inversion-layer bit lines under assist gates, reduces the dispersal of programming characteristics and also reduces the time overhead of pre-charging the bit lines. This self-boosted charge-injection scheme achieves a programming throughput of 10MB/s.
Conventional phase-locked loops (PLL's) lack speed, because ordinary phase comparators cannot achieve time-continuous phase detection, introducing equivalent time delays into the loops. This paper presents a PLL reconstructed to derive time-optimal responses. First, VCO's and filters are replaced by time-discrete ones, eliminating the stability problem caused by the time delay. Second, period rather than frequency is employed as the controlled variable for utilizing digital phase comparators as linear time comparators. A prototype consisting of about 20 IC's is tested.
Abstract The R175H mutation of p53 which account for approximately 6% of the missense mutations of identified in human cancer is one of the most common mutations, and cancer cells with this mutation stably express the R175H protein in the nucleus. Targeting R175H overexpressing cells by synthetic lethality is one of the extremely effective strategies for cancer therapy. To identify the synthetic lethal gene interacting with R175H, we conducted high throughput screening using a tetracycline-inducible R175H expression system in SF126 cells and comprehensive shRNA library carried by lentivirus. We identified 906 candidate gene suppressions that may lead to accelerated cell growth inhibition in the presence of R175H (p<0.05, n=3). Among these, we selected 50 genes (21 genes from the group with the smallest p-values, 20 genes from the group with the largest fold change, and 9 genes reproduced by different siRNA sequences) for further validation testing. By transfection of siRNA of these candidate genes into five R175H expressing cell lines and four TP53-null cell lines, we selected five candidate genes that significantly lead R175H expressing cells to strong cell growth inhibition. Inhibitor of differentiation 1 (ID1) was one of the five candidate genes, and its suppression by siRNA resulted in the acceleration of growth inhibition in cell lines expressing endogenous R175H; however, this was not observed in TP53-null cell lines. The transient expression of R175H in TP53-null cell lines (PC3) and suppression of ID1 and/or TP53 R175H in cell lines with endogenous R175H revealed that cell growth inhibition by ID1 suppression depended on the expression of R175H, and not that of other common p53 mutants (e.g., R273H). Flow cytometric analysis exhibited that ID1 suppression resulted in G1 arrest, and the arrest was accelerated by the expression of R175H. In conclusion, ID1 is a synthetic lethal gene that interacts with R175H and is considered to be a novel molecular target for cancer therapy in R175H expressing cells. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2956. doi:1538-7445.AM2012-2956
The preparation of bioceramics with ordered mesoporous structures is of importance for biomedical technology, for the design of bone and dental grafts with regeneration purposes. Here we demonstrate that hexagonal mesoporous SiO2−CaO−P2O5 bioglasses (MBG) with high calcium content are the first known bioceramics that exhibit amorphous calcium phosphate (ACP)−octacalcium phosphate (OCP)−calcium deficient carbonatehydroxyapatite (CDHA) maturation as biomineralization governing mechanism in simulated body fluid (SBF), similarly to the in vivo biomineralization process. The unique characteristics of hexagonal MBGs lead to a local acid pH at the bioceramic surface that allows the formation of metastable OCP. Besides, 3D cubic MBG has been also synthesized, exhibiting higher surface area and porosity. The 3D reconstruction carried out by electron microscopy evidence a 3D bicontinuous network comprising a pair of rods mutually intertwined, creating the pore system available in three dimensions. This 3D pore system provides not only high surface area and porosity but also easier interchange of ions, increasing mass transport and diffusion processes. The final result is that 3D cubic MBGs exhibit an accelerated bioactivity behavior, forming a bonelike apatite phase on the surface, 1 h after coming into contact with SBF.
