scholarly journals Room Temperature Enhancement of Electronic Materials by Superacid Analogues

ACS Nano ◽  
2022 ◽  
Author(s):  
Sophie L. Pain ◽  
Nicholas E. Grant ◽  
John D. Murphy
Keyword(s):  
Room Temperature ◽  
Electronic Materials ◽  
Temperature Enhancement

Ambient Temperature Synthesis of Bulk Intermetallics

1994 ◽  
Vol 350 ◽  
Author(s):  
M. Ratzker ◽  
D. S. Lashmore ◽  
M. P. Dariel
Keyword(s):  
Ambient Temperature ◽  
Room Temperature ◽  
Binary Systems ◽  
Electronic Materials ◽  
Close Contact ◽  
Interface Area ◽  
Compound Formation ◽  
Intermetallic Compound Formation ◽  
Powder Particles ◽  
Size Powder

AbstractRoom-temperature intermetallic compound formation occurs when one of the component metals has a very low melting point or when two metals in close contact interdiffuse very rapidly. Compound formation at room temperature at the interface of superposed thin films has been observed in several instances, often in systems relating to electronic materials. The overall amount of compound produced in such configurations, however, is limited, due to the intrinsic limitations involved in the thin layer geometry. Bulk quantities of intermetallic can be produced at ambient temperature in solids by increasing the interface area between the components that interdiffuse rapidly. This condition can be achieved by having small size powder particles of one component coated with a layer of the second component. The very large interface area leads to rapid formation of bulk quantities of compounds even at ambient temperature. By appropriate control of the initial constituents and the coating parameters, it is possible to custom-prepare various intennetallic compounds present in binary systems such as silver-tin, gold-tin and silver-indium in which fast interdiffusion takes place.

scholarly journals Room-temperature Pd/Ag direct arylation enabled by a radical pathway

2020 ◽  
Vol 16 ◽  
pp. 384-390
Author(s):  
Amy L Mayhugh ◽  
Christine K Luscombe
Keyword(s):  
Room Temperature ◽  
Electronic Materials ◽  
Cross Coupling ◽  
Underlying Mechanism ◽  
Conjugated Materials ◽  
Direct Arylation ◽  
Materials Development ◽  
Organic Electronic Materials ◽  
Direct Arylation Polymerization ◽  
The Cost

Direct arylation is an appealing method for preparing π-conjugated materials, avoiding the prefunctionalization required for traditional cross-coupling methods. A major effort in organic electronic materials development is improving the environmental and economic impact of production; direct arylation polymerization (DArP) is an effective method to achieve these goals. Room-temperature polymerization would further improve the cost and energy efficiencies required to prepare these materials. Reported herein is new mechanistic work studying the underlying mechanism of room temperature direct arylation between iodobenzene and indole. Results indicate that room-temperature, Pd/Ag-catalyzed direct arylation systems are radical-mediated. This is in contrast to the commonly proposed two-electron mechanisms for direct arylation and appears to extend to other substrates such as benzo[b]thiophene and pentafluorobenzene.

scholarly journals Nanowires by Step Decoration

MRS Bulletin ◽  
1999 ◽  
Vol 24 (8) ◽  
pp. 20-24 ◽  
Author(s):  
F.J. Himpsel ◽  
T. Jung ◽  
A. Kirakosian ◽  
J.-L. Lin ◽  
D.Y. Petrovykh ◽  
...  
Keyword(s):  
Quantum Wells ◽  
Electronic Properties ◽  
Self Assembly ◽  
Room Temperature ◽  
Electronic Materials ◽  
Layer By Layer ◽  
Optimum Thickness ◽  
Single Digit ◽  
Cooperative Phenomenon ◽  
Nanometer Regime

Recent advances in the control of thin films and surfaces have brought an intriguing question within reach: Is it possible to tailor the electronic properties of solids by controlling them layer by layer or row by row? Customized molecules are commonplace in biochemistry. Can the same idea be brought to bear on solids and electronic materials? Electronic properties of semiconductor devices have been controlled by hetero-structures, quantum wells, and super-lattices. Magnetism as a cooperative phenomenon lends itself to manipulation in small structures, where neighbor atoms can be replaced systematically by species with stronger or weaker magnetism. In fact, a class of magnetic/nonmagnetic multilayers termed spin valves has recently been introduced into commercial read heads for magnetically stored data. The optimum thickness of their active region lies in the single-digit-nanometer regime.The smallest nanostructures may be viewed as objects consisting only of interfaces with no bulk behind them. More typically, single-digit-nanometer dimensions are sufficient for realizing the benefits of structuring (e.g., operating a quantum-well device at room temperature). This regime is difficult to reach with lithography methods, particularly when macroscopic amounts are to be fabricated. Self-assembly becomes the method of choice.

Electronic transport and microstructure in MoSi2 thin films

1986 ◽  
Vol 1 (3) ◽  
pp. 493-502 ◽  
Author(s):  
T.L. Martin ◽  
J.E. Mahan
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Electronic Materials ◽  
Ion Beam ◽  
Molybdenum Disilicide ◽  
Residual Resistivity ◽  
Silicon Substrates ◽  
Tetragonal Crystal ◽  
Average Grain Size ◽  
Polysilicon Layer

Molybdenum disilicide thin films having the tetragonal crystal structure were prepared by furnace reaction of ion-beam-sputtered molybdenum layers with silicon substrates. The room temperature intrinsic resistivity is ∼20 μΩ cm. The Hall effect indicates predominantly hole conduction. Geometrical magnetoresistance measurements provide a carrier mobility estimate of 90 cm2 /V.s at room temperature. The Hall mobility is much less than this; the large difference between the two mobility values suggests multiband conduction. An isotropic, degenerate, twoband model may be fitted to the data with a comparatively low majority carrier concentration (holes) of ∼ 1.5 × 1021 cm−3 Regarding the effects of microstructure on transport, the residual resistivity for films formed on 1-0-0 silicon wafers is much greater than for those formed on an (LPCVD) polysilicon layer: 92 vs 29 μΩ cm, respectively. A correlation with average grain size for the two sample types suggests that grain boundary scattering is the principal cause of the residual resistivity. electronic materials; electrical properties; thin film

Room temperature enhancement and inhibition of spontaneous emission in semiconductor microcavities

2000 ◽  
Vol 77 (9) ◽  
pp. 1345-1347 ◽  
Author(s):  
G. Bourdon ◽  
I. Robert ◽  
R. Adams ◽  
K. Nelep ◽  
I. Sagnes ◽  
...  
Keyword(s):  
Spontaneous Emission ◽  
Room Temperature ◽  
Semiconductor Microcavities ◽  
Temperature Enhancement

Thermal Conductivity Measurement of Graphene Exfoliated on Silicon Dioxide

2010 ◽  
Vol 133 (2) ◽  
Author(s):  
Jae Hun Seol ◽  
Arden L. Moore ◽  
Li Shi ◽  
Insun Jo ◽  
Zhen Yao
Keyword(s):  
Thermal Conductivity ◽  
Silicon Dioxide ◽  
Ultrathin Films ◽  
Room Temperature ◽  
Electronic Materials ◽  
Conductivity Measurement ◽  
Thermal Conductivity Measurement ◽  
Resistance Thermometer ◽  
Numerical Heat Transfer ◽  
Measurement Results

We have developed a nanofabricated resistance thermometer device to measure the thermal conductivity of graphene monolayers exfoliated onto silicon dioxide. The measurement results show that the thermal conductivity of the supported graphene is approximately 600 W/m K at room temperature. While this value is lower than the reported basal plane values for graphite and suspended graphene because of phonon leakage across the graphene-support interface, it is still considerably higher than the values for common thin film electronic materials. Here, we present a detailed discussion of the design and fabrication of the measurement device. Analytical and numerical heat transfer solutions are developed to evaluate the accuracy and uncertainty of this method for thermal conductivity measurement of high-thermal conductivity ultrathin films.

Dependence of Intergranular Fracture on Boundary Topography and Cohesion

1973 ◽  
Vol 31 ◽  
pp. 150-151
Author(s):  
J. E. Doherty ◽  
A. F. Giamei ◽  
B. H. Kear ◽  
C. W. Steinke
Keyword(s):  
Grain Boundary ◽  
Room Temperature ◽  
Nickel Base Superalloy ◽  
Boundary Shear ◽  
Room Temperature Ductility ◽  
Solid Solution Matrix ◽  
Nickel Base ◽  
Solution Matrix ◽  
Different Levels ◽  
Base Superalloy

Recently we have been investigating a class of nickel-base superalloys which possess substantial room temperature ductility. This improvement in ductility is directly related to improvements in grain boundary strength due to increased boundary cohesion through control of detrimental impurities and improved boundary shear strength by controlled grain boundary micros true tures.For these investigations an experimental nickel-base superalloy was doped with different levels of sulphur impurity. The micros tructure after a heat treatment of 1360°C for 2 hr, 1200°C for 16 hr consists of coherent precipitates of γ’ Ni3(Al,X) in a nickel solid solution matrix.

Hepatocyte Alterations in Guinea Pigs FED Polychlorinated Biphenyls (PCBs), Dibenzodioxins (PCDD), AND DIBENZOFURANS (PCDF)

1982 ◽  
Vol 40 ◽  
pp. 56-57
Author(s):  
J. N. Turner ◽  
D. N. Collins
Keyword(s):  
Guinea Pigs ◽  
Room Temperature ◽  
Dose Group ◽  
Methyl Cellulose ◽  
Uranyl Acetate ◽  
Target Organ ◽  
Office Building ◽  
Lead Citrate ◽  
Control Groups ◽  
Cooling Fluid

A fire involving an electric service transformer and its cooling fluid, a mixture of PCBs and chlorinated benzenes, contaminated an office building with a fine soot. Chemical analysis showed PCDDs and PCDFs including the highly toxic tetra isomers. Guinea pigs were chosen as an experimental animal to test the soot's toxicity because of their sensitivity to these compounds, and the liver was examined because it is a target organ. The soot was suspended in 0.75% methyl cellulose and administered in a single dose by gavage at levels of 1,10,100, and 500mgm soot/kgm body weight. Each dose group was composed of 6 males and 6 females. Control groups included 12 (6 male, 6 female) animals fed activated carbon in methyl cellulose, 6 males fed methyl cellulose, and 16 males and 10 females untreated. The guinea pigs were sacrificed at 42 days by suffocation in CO2. Liver samples were immediately immersed and minced in 2% gluteraldehyde in cacadylate buffer at pH 7.4 and 4°C. After overnight fixation, samples were postfixed in 1% OsO4 in cacodylate for 1 hr at room temperature, embedded in epon, sectioned and stained with uranyl acetate and lead citrate.

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