Influence of post-weld heat treatment (PWHT) on the structure and properties of welded joints of chromium–nickel stainless steel with soft martensite

This paper reviews the results of investigations on how post-weld heat treatment (PWHT) influences the hardness and microstructures of welded joints in stainless steel X3Cr-NiMo 13-4. It is known that welding leads to high segregation of components in the solidification process, which has an influence on phase transitions in PWHT. The investigated steel has a very narrow PWHT range, about 600–620°C, which provides optimum levels of hardness and toughness. Excessive annealing temperature leads to decreased toughness, which in turn causes exceeding of the A_c1 temperature in the segregation range, which then leads to increased ‘fresh’ martensite content.     

Gas-phase electrophoretic molecular mobility analysis of size and stoichiometry of complexes of a common cold virus with antibody and soluble receptor molecules

Attachment of a nonaggregating monoclonal antibody and of a soluble recombinant receptor molecule to the icosahedral nonenveloped human rhinovirus serotype 2 was studied with a nanoelectrospray ionization gas-phase electrophoretic molecular mobility analyzer (nESI-GEMMA). The virus mass, as determined via nESI-GEMMA, was within instrument accuracy (+/-6%) close to the theoretical value (8 x 10(6) Da) calculated from the sum of all constituents of one virus particle (60 copies of each of the four viral capsid proteins, the RNA genome, and one copy of the RNA-linked protein VpG). The formation of virus-antibody complexes of different stoichiometries (up to a mass 12.5 x 10(6) Da corresponding to 30 attached antibodies) and virus-receptor complexes (up to a mass 8.8 x 10(6) Da corresponding to 12 attached receptor molecules) was monitored. Via the volume derived from the electrophoretic mobility diameter (EMD), the stoichiometry of the HRV complexes was calculated. The accuracy of the EMD was within +/-0.5 nm, which corresponds to an accuracy of +/-4 antibodies and +/-5 receptor molecules in the respective complexes. For the first time, we here demonstrate the use of nESI-GEMMA for the analysis of the size and stoichiometry of biomolecules in high-order complexes in real time under normal pressure conditions.     

Standard atomic weights of the elements (1988)

Standard atomic weights of the elements (1988)     

Effects of examples and embedded questions on the accuracy of comprehension self-assessments.

This study extends research by Glenberg, Sanocki, Epstein, and Morris (1987) by suggesting that the accuracy of students' comprehension-monitoring self-assessments can be improved if they read expository text that contains illustrative examples and embedded questions. Students were asked to read text under different study conditions. It is argued that examples and embedded questions provide students with an opportunity to test their own level of understanding of passage content and, therefore, result in more accurate self-assessments of comprehension than does plain text. Students who read text with both examples and questions assessed their own comprehension more accurately than did students reading plain text. These students also made more accurate posttest predictions of test performance. It appears that active self-testing improves one's calibration of comprehension. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A high-performance 0.5-μm BiCMOS technology for fast 4-Mb SRAMs

A high-performance 0.5-μm BiCMOS technology has been developed. Three layers of polysilicon are used to achieve a compact four-transistor SRAM bit cell size of less than 20 μm² by creating self-aligned bit-sense and V_ss contacts. A WSi_x polycide emitter n-p-n transistor with an emitter area of 0.8×2.4 μm² provides a peak cutoff frequency (f_T) of 14 GHz with a collector-emitter breakdown voltage (BV_CFO) of 6.5 V. A selectively ion-implanted collector (SIC) is used to compensate the base channeling tail in order to increase f_T and knee current without significantly affecting collector-substrate capacitance. ECL gate delays as fast as 105 ps can be obtained with this process     

Experimental Evaluation of the Optical Properties of Porous Silica/Carbon Composite Particles

Light scattering by porous spheroidal silica and several silica/carbon composite particles having different carbon contents was systematically investigated using a laser particle counter coupled with a pulse height analyzer (LPC-PHA). A new and simple method for the measurements of the effective complex refractive index of silica/carbon composite particles using a conventional LPC-PHA system and a differential mobility analyzer was introduced and tested. Challenge particles, from pure silica to silica/carbon compounds having a gradually increasing porous structure, were prepared by spray-drying methods for use in testing of the inversion method. By representing the deviation of the real part of the refractive index of a porous silica particle versus the size on a topographical map, the inversion method for the determination of the real part of the refractive indices was found to have a satisfactory precision. Furthermore, the method can be applied to the measurement of the complex refractive index of silica/carbon composite particles by extending the best fitting method to complex refractive indices. The effective complex refractive index of silica/carbon composite particles as a function of their carbon content is reported. Both the real and imaginary parts of the complex refractive index were increased with increasing carbon content of the composite particles.     

Integration of a double-polysilicon emitter-base self-alignedbipolar transistor into a 0.5-μm BiCMOS technology for fast 4-MbSRAM's

The single-polysilicon non-self-aligned bipolar transistor in a 0.5-μm BiCMOS technology has been converted into a double-polysilicon emitter-base self-aligned bipolar transistor with little increase in process complexity. Improved bipolar performance in the form of smaller base resistance and base-collector capacitance, larger knee current, higher peak cutoff frequency, and shorter ECL gate delay has been demonstrated. This technology will prove useful in meeting the requirements for higher performance in fast, high-density, SRAM circuits     

Einfluß der Wärmebehandlung auf die Schneidhaltigkeit von Werkzeugen beim Stanzen von Dynamoblechen unterschiedlicher Schneidbarkeit

An elf verschiedenen Güten von drei Dynamoblechen mit 2,0, 2,3 und 3,6 W/kg Ummagnetisierungsverlust Untersuchung ihrer Schneidbarkeit sowie der Schneidhaltigkeit von zehn verschieden wärmebehandelten Stanzwerkzeugen aus den Stählen 100 Cr 6 mit 0,95% C und 1,46% Cr, X 210 Cr 12 mit 1,96% C und 11,75% Cr und S12–1–4–5 mit 1,45% C, 4,27% Cr, 5,35% Co, 0,84% Mo, 3,83% V und 12,51% W sowie aus Hartmetall mit 6,53% C, 2,05% Cr, 0,1 bis 0,2% Co, 1,98% Mo und 24,91% Ti. Unterschiedliche Vorabnutzung der einzelnen Werkzeuge zur Ermittlung ihres Verschleiβes bei verschiedenen Abnutzungsstufen. Anschlieβende Radioaktivierung und Messung des bei weiteren Stanzungen anfallenden Abriebes über seine emittierten γ-Strahlen. Einordnung der untersuchten Bleche in Gütegruppen sowie Vergleich der Schneidhaltigkeit der einzelnen Werkzeuge.