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Modules, laboratory

A three-module laboratory In the Birck Nanotechnology Center. The multiple-module design fosters multiple users on similar projects, thus enhancing the potential of collaborative research. [Pg.299]

The axial filter (Oak Ridge National Laboratory) (30) is remarkably similar to the dynamic filter in that both the rotating filter element and the outer shell are also cylindrical. An ultrafiltration module based on the same principle has also been described (31). Unlike the disk-type European dynamic filters described above, the cylindrical element models are not so suitable for scale-up because they utilize the space inside the pressure vessel poorly. [Pg.410]

A market for electrooptic modulators does not exist as of this writing much of the motivation for developing prototype devices derives from anticipated needs of the information superhighway and the cable television industry. Various corporate research laboratories have produced prototype modulators that can operate to 60 GH2 (7,19—28). Nontechnical issues such as the early implementation of direct (satellite transmission) television may also affect the market success of these electrooptic modulators. [Pg.137]

Amorphous Silicon. Amorphous alloys made of thin films of hydrogenated siUcon (a-Si H) are an alternative to crystalline siUcon devices. Amorphous siUcon ahoy devices have demonstrated smah-area laboratory device efficiencies above 13%, but a-Si H materials exhibit an inherent dynamic effect cahed the Staebler-Wronski effect in which electron—hole recombination, via photogeneration or junction currents, creates electricahy active defects that reduce the light-to-electricity efficiency of a-Si H devices. Quasi-steady-state efficiencies are typicahy reached outdoors after a few weeks of exposure as photoinduced defect generation is balanced by thermally activated defect annihilation. Commercial single-junction devices have initial efficiencies of ca 7.5%, photoinduced losses of ca 20 rel %, and stabilized efficiencies of ca 6%. These stabilized efficiencies are approximately half those of commercial crystalline shicon PV modules. In the future, initial module efficiencies up to 12.5% and photoinduced losses of ca 10 rel % are projected, suggesting stabilized module aperture-area efficiencies above 11%. [Pg.472]

Copper Indium Diselenide. CuInSe2 (CIS) has proven to be one of the most promising thin-film photovoltaic materials. CIS ahoy materials have yielded smah-area (ca 1 cm ) laboratory devices with efficiencies in excess of 17% and large-area (ca 0.5 m ) monolithic integrated modules with efficiencies in excess of 11%, and have shown excehent radiation hardness. [Pg.472]

The intrinsic rejection and maximum obtainable water flux of different membranes can be easily evaluated in a stirred batch system. A typical batch unit (42) is shown in Figure 5. A continuous system is needed for full-scale system design and to determine the effects of hydrodynamic variables and fouling in different module configurations. A typical laboratory/pilot-scale continuous unit using computer control and on-line data acquisition is shown in Figure 6. [Pg.149]

Interface states played a key role in the development of transistors. The initial experiments at Bell Laboratories were on metal/insulator/semiconductor (MIS) stmctures in which the intent was to modulate the conductance of a germanium layer by applying a voltage to the metal plate. However, only - 10% of the induced charges were effective in charging the conductance (3). It was proposed (2) that the ineffective induced charges were trapped in surface states. Subsequent experiments on surface states led to the discovery of the point-contact transistor in 1948 (4). [Pg.348]

Some very high resolution or ultrasensitive spectroscopies emerging as of ca 1996 were beam spectroscopy, multiphoton absorption and ionisation, and frequency-modulation spectroscopy (8). Most of these were used primarily for laboratory research as of the mid-1990s, but eventual appHcation to analytical or sensor appHcations is expected. [Pg.321]

For applied work, an optical characterization technique should be as simple, rapid, and informative as possible. Other valuable aspects are the ability to perform measurements in a contactless manner at (or even above) room temperature. Modulation Spectroscopy is one of the most usehil techniques for studying the optical proponents of the bulk (semiconductors or metals) and surface (semiconductors) of technologically important materials. It is relatively simple, inexpensive, compact, and easy to use. Although photoluminescence is the most widely used technique for characterizing bulk and thin-film semiconductors. Modulation Spectroscopy is gainii in popularity as new applications are found and the database is increased. There are about 100 laboratories (university, industry, and government) around the world that use Modulation Spectroscopy for semiconductor characterization. [Pg.387]

Boris, J. P. 1976. Flux-Corrected Transport modules for solving generalized continuity equations. NRL Memorandum report 3237. Naval Research Laboratory, Washington, D.C. [Pg.137]

SEC measurements were made using a Waters Alliance 2690 separation module with a 410 differential refractometer. Typical chromatographic conditions were 30°C, a 0.5-ml/min flow rate, and a detector sensitivity at 4 with a sample injection volume of 80 fil, respectively, for a sample concentration of 0.075%. All or a combination of PEO standards at 0.05% concentration each were used to generate a linear first-order polynomial fit for each run throughout this work. Polymer Laboratories Caliber GPC/SEC software version 6.0 was used for all SEC collection, analysis, and molecular weight distribution overlays. [Pg.502]

An example of a modem instrument of this type is the Coming Model 410 flame photometer. This model can incorporate a lineariser module which provides a direct concentration read-out for a range of clinical specimens. Flame photometers are still widely used especially for the determination of alkali metals in body fluids, but are now being replaced in clinical laboratories by ion-selective electrode procedures (see Section 15.7). [Pg.798]

After this step, the understanding of microwave electrochemical mechanisms deepened rapidly. G. Schlichthorl went to the laboratory of L. Peter to combine potential-modulated microwave measurements with impedance measurements, while our efforts focused on laser pulse-induced microwave transients under electrochemical conditions. It is hoped that the still relatively modest knowledge provided will stimulate other groups to participate in the development of microwave photoelectrochemistry. [Pg.441]

System control and data acquisition are done with a personal computer using Paragon software. About 150 input and output modules were used for the two laboratory cells. This is expensive and may seem excessive, but a lot of the inputs and outputs are used for safety purposes so that the cell can operate unattended 24 hr a day, 7 days a week to get good long-term data. [Pg.538]

The modules are computer-based laboratory simulations with engaging activities that emphasize experimental design and visualization of structures and processes at the molecular level. The modules are designed to help students connect chemical principles from lecture with their practical applications in the lab. Every module has a built-in accountability feature that records section completion for use in setting grades and a workbook for students to record and interpret their work. [Pg.22]

Used either as prelaboratory preparation for related laboratory activities or to expose students to additional laboratory activities not available in their program, these modules motivate students to learn by proposing real-life problems in a virtual environment. Students make decisions on experimental design, observe reactions, record data, interpret these data, perform calculations, and draw conclusions from their results. Following a summary of the module, students test their understanding by applying what they have learned to new situations or by analyzing the effect of experimental errors. [Pg.22]

The following points are worthy of note in terms of the placement of data. In the case of studies with multiple objectives, reports should be placed in the section corresponding to their primary purpose. Reports of laboratory studies conducted with human materials to investigate pharmacokinetic effects should be placed in Section 5.3.2 of the clinical module, as opposed to the non-clinical module. A US submission requires that the individual case report forms of all trial subjects that died or were dropped from a study due to adverse events are included in Section 5.3.7. [Pg.105]

Theoretical level populations. Sinee there are population variations on time seale shorter than some level lifetimes, a complete description of the excitation has been modeled solving optical Bloch equations Beacon model, Bellenger, 2002) at CEA. The model has been compared with a laboratory experiment set up at CEA/Saclay (Eig. 21). The reasonable discrepancy when both beams at 589 and 569 nm are phase modulated is very likely to spectral jitter, which is not modeled velocity classes of Na atoms excited at the intermediate level cannot be excited to the uppermost level because the spectral profile of the 569 nm beam does not match the peaks of that of the 589 nm beam. [Pg.266]

The photovoltaics industry could expand rapidly if the efficiency of polycrystalline modules could be increased to 15 percent, if these modules could be built with assurance of reliability over a 10- to 20-year period, and if they could be manufactured for 100 or less per square meter. Solar energy research has been largely directed toward only one of these issues efficiency. All research aimed at reducing manufacturing costs has been done in industry and has been largely empirical. Almost no fundamental engineering research has been done on either the laboratory scale or the pilot plant scale for cost-effective processes for the production of photoconverters. [Pg.62]

Adapting the system to a mobile unit involved redesigning the instrumentation for portability and mounting it into a 3 A x 5-ft steel cart. A major requirement for this unit was containment of the Line-Lite laser, optical elements, and detection module in a clean laboratory environment. Other requirements included high ground clearance, accessibility to electricity within 100 ft, and durable construction. The entire mobile unit can be powered by a 5-kW gasoline generator. [Pg.234]

A less expensive variation of modular furniture is in use in some European laboratories. The bench frames are built of permanently installed steel channels complete with tops. Modules containing combinations of drawers and cupboards can be hooked into the system and changed as needed, but utility outlets are fixed. [Pg.85]

Figure 3 Plan for main laboratory room showing furniture modules with catalog numbers. Figure 3 Plan for main laboratory room showing furniture modules with catalog numbers.

See other pages where Modules, laboratory is mentioned: [Pg.298]    [Pg.298]    [Pg.1486]    [Pg.197]    [Pg.112]    [Pg.436]    [Pg.72]    [Pg.450]    [Pg.472]    [Pg.394]    [Pg.155]    [Pg.315]    [Pg.509]    [Pg.222]    [Pg.88]    [Pg.105]    [Pg.363]    [Pg.96]    [Pg.268]    [Pg.438]    [Pg.462]    [Pg.234]    [Pg.103]    [Pg.46]    [Pg.439]    [Pg.85]    [Pg.86]    [Pg.85]    [Pg.214]   
See also in sourсe #XX -- [ Pg.462 ]




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