Technical limits

Due to the technical limitations of the present equipment, some blurring of the images was caused by the stability of the turntable rotation axis and its horizontal leveling. 

Solar cells have been used extensively and successfully to power sateUites in space since the late 1950s, where their high power-to-weight ratio and demonstrated rehabiUty are especially desirable characteristics. On earth, where electrical systems typically provide large amounts of power at reasonable costs, three principal technical limitations have thus far impeded the widespread use of photovoltaic products solar cells are expensive, sunlight has a relatively low power density, and commercially available solar cells convert sunlight to electricity with limited efficiency. Clearly, terrestrial solar cells must be reasonably efficient, affordable, and durable. International efforts are dedicated to obtaining such devices, and a number of these activities have been reviewed (1). 

Technical limitations. Given the complexity of present manufacturing processes, waste streams exist that cannot be reduced with current technology. The need for continued research and development is evident. 

There are, however, technical limitations to substitution. Some materials are used in ways not easily filled by others. Platinum as a catalyst, liquid helium as a refrigerant, and silver on electrical contact areas cannot be replaced they perform a unique function - they are, so to speak, the vitamins of engineering materials. Others - a replacement for tungsten for lamp filaments, for example - would require the development of a whole new technology, and this can take many years. Finally,... 

The first successful chiral resolutions through enantioselective membranes have been published recently, but few cases are applicable to the preparative scale, mainly due to mechanical and technical limitations. Low flow rates, saturation of the chiral selectors and loss of enantioselectivity with time are some of the common problems encountered and that should be solved in the near future. 

Standard version Search of plastics by name, with technical limitations, price level, producer, processing method etc., and search of/comparison of equivalent materials ... 

Search by name, technical limitations, or equivalent material. 

In certain direct steam-contact process applications (such as in food and beverage processing or pharmaceutical preparations) the use of amine-based products in steam and condensate systems is subject to legal restrictions. Also, the use of ammonia or amines may be dependent on the materials of construction employed or technical limitations (such as the risk of copper alloy corrosion). 

Eor (1), MSWIs, the maximum bonus is limited by the calorific value of the plastics waste (about 40 MJ/kg). Eurthermore, the energy recovery is relatively low due to technical limitations in comparison to normal power plants. Normally, at best some 20% electrical energy is recovered (or some 50%-70% calculated as primary energy). 

Plants grown for longer periods in solid supports such as sand or soil repre-.sent the next level of complexity and, although other techniques are available, carbon flow is most frequently estimated using C labeling experiments. In the laboratory, COt can be supplied to shoots either as a short pulse or continuously, and the carbon flow can be monitored. In the field, due to technical limitations, only COi pulse labeling procedures are possible. A final approach, termed crop studies, involves the measurement of components of crop growth from which... 

To identify further which substance, cafestol or kahweol, or both, was inducing changes in serum cholesterol, the investigators attempted, but failed due to technical limitations, to separate the two chemical compounds. Alternatively, they compared coffee oil from Arabica vs. Robusta coffee beans. Arabica beans contain both cafestol and kahweol, while Robusta beans contain cafestol, but almost no kahweol. The investigators found that Arabica and Robusta oils both increased serum cholesterol and triglyceride levels comparably. They thus concluded that cafestol is, and kahweol might be, a serum cholesterol raising factor. 

Research studies investigating exposure to JP-8 via oral administration offers an alternative examination of the systemic effects of JP-8 on immune function. Admittedly, this does not ideally mimic occupational exposures, but it does eliminate technical limitations associated with inhalation and dermal penetration of JP-8. It has been suggested that the only route available that can assess the whole mixture (JP-8 in its entirety), without fractionation due to volatilization of components, is the oral route [1] as select components of JP-8 may have increased permeability during dermal exposure, other specific components may be enriched following inhalation exposures[71]. 

Many commercial split flow capillary LC systems incorporate a nano flow sensor mounted online to the capillary channel. The split flow system can be easily modified from a conventional system and performs satisfactorily for capillary LC applications. However, the split flow system may require thermal control and the LC solvent requires continuous degassing. In addition, the system may not work reliably at a high flow split ratios and at pressures above 6000 psi due to technical limitations of the fused silica thermal conductivity flow sensor. The split flow system based on conventional check valve design may not be compatible with splitless nano LC applications. The conventional ball-and-seat check valve is not capable of delivering nano flow rates and is not reliable for 7/24 operation at low flow. 

Depolymerization processes have been proposed for poly(butylene terephtha-late) by the glycolysis of PBT with 1,4-butanediol and a titanium catalyst [65]. Methanolysis of poly(ethylene naphthalate) to dimethyl naphthalate and ethylene glycol has also been proposed [66, 67], but not implemented. The lack of commercial depolymerization of PEN is probably due not to technical limitations, but to insufficient supplies of PEN polymer feedstock to meet the minimum quantities needed for economical operations. 

The only disadvantage inherent in the technique is that it takes no account of possible synergistic interaction between the osmogenes that constitute an odorous emission. Technical limitations which may be improved upon are thought to be -... 

TECHNICAL LIMITATIONS IN THE STUDY OF MARINE ORGANIC MATTER AND VARIOUS WORK-AROUNDS... 

The SQUID obviously has several potential advantages for on-line applications. It can operate at very low inhomogeneous magnetic fields, avoiding the need for large expensive shimmed magnets. It also does not require tuning and has very low power requirements. However there are also severe technical limitations to be overcome before it can be used in on-line commercial operations. The whole SQUID needs to be immersed in liquid helium and a conventional RF coil is still needed to excite the NMR resonance. It remains to be seen whether such devices will find future on-line application in horticulture. 

The structure of the condensed chromatin fiber is still under discussion [1,23,54], with two competing models the original solenoid model of Finch and Klug [16], and the straight-linker model [12,14,55]. Assessing the structure in vivo or in situ has proven impossible thus far, due to technical limitations. Chromatin fibers released from nuclei into solution by nuclease treatment have been widely used as models for fiber structure such fibers are extended at low ionic strength and condensed at ionic strengths believed to be close to those found in vivo ( 150 mM Na" " or 0.35 mM Mg " "). The salt-induced fiber compaction has been extensively studied in the past but is still poorly understood in terms not only of the details of the structure but also in terms of the molecular mechanisms of the compaction process. 

The public discourse about hydropower in Switzerland went through a number of quite clearly demarcated phases. In the first phase, which started between 1880 and 1914, the electrical utopia based on white coal sparked a national consensus to develop alpine hydropower plants [10]. However, due to technical limitations, the majority of currently running large-scale hydropower plants in the Swiss Alps was constructed in the 1950s and 1960s. As a result of this rapid expansion, almost all major streams in the Alpine region are now impacted by hydropower plants and their operation [6]. 

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