Problems and Possible Solutions

The tritiation procedures given in Table 18.1 all have serious limitations or disadvantages. Thus, for all three hydrogen isotope exchange reactions, HTO is used as the donor. For health and safety reasons 50 Ci mL (1 Ci = 37 GBq), corresponding to dose on 2% isotopic abundance, is the highest specific activity that we have used and this inevitably limits the maximum specific activity of the products that can be obtained via these routes. 

Although many pharmaceutical compounds are unable to withstand harsh acidic conditions a surprisingly large number of compounds have been labeled via this route. Werstiuk [11] for example has reduced the acid concentration but increased the temperature, one effect more than compensating for the other - however, the time required is frequently very long, extending into days. Ion exchange resins, both acid and base forms, can be used to overcome separation problems [12, 13]. 

recoil labeling (which does, in fact, predate the Wilzbach method)  

A detailed account of the theory behind the interaction of microwaves with matter is beyond the scope of this Chapter but there are several excellent and recent reviews available [34-38 and other chapters in this book]. 

Investigations of the mechanisms and kinetics of microwave-enhanced reactions is at an early stage but the development [39] of a microwave reactor/ultraviolet/ visible hybrid spectrometer will be a valuable tool. It has already been used to study the formation of benzimidazole from the reaction of 1,2-diaminobenzene and formic acid. 

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Write move 3 of your proposal Be sure to (1) remind reader of preliminary results, (2) describe procedures and instrumentation in a logical manner (e.g., sequentially, by underlying themes, by desired outcomes, or some combination), and (3) anticipate obstacles and suggest alternatives with a contingency plan (that identifies both problems and possible solutions). Use appropriate headings and subheadings in your writing. 

DB Rodriguez-Amaya. Provitamin A determination problems and possible solutions. Food Nutr Bull 12 246-250, 1990. 

Bakhtiar, R., and Majumdar, T. K. (2007). Tracking problems and possible solutions in the quantitative determination of small molecule chugs and metabolites in biological fluids using liquid chromatography-mass spectrometry. J. Pharmacol. Toxicol. Methods 55 227-243. 

Guo, Z. (1993). On validation of source and sink models problems and possible solutions, in Modelling of Indoor Air Quality and Exposure, N.L. Nagda (Ed.), ASTM STP 1205, American Society for Testing and Materials, Philadelphia, PA, USA, pp. 131-144. 

The parallelism of sudighi-driven photosynthesis/respiralion and the chemoUthoiophic oxidatiC ) of. sulfide and suKur by bacteria (page 890), as well as the possibility of metal (oxiuly near hydrothermal vents (page %Z>, has been noted. Surest other problems and possible solutions to be expected from hydrothenna vent or inisms. ... 

Guo Z. (1993) On Validation of Source and Sink models Problems and Possible Solutions. In Nagda,... 

Red and yellow tropical soils (latosols) are generally recognized as among the most difficult of all widely-occurring natural soils to convert into agricultural soils that can be cropped satisfactorily year after year. Most of them are really problem soils that cannot be handled by the methods used in farming soils of cooler climates. Some of the problems and possible solutions are outlined below. 

Chemical Communication and Aquaculture of Decapod Crustaceans Needs, Problems, and Possible Solutions... 

Payne, J.A., Jaynes, R.A., and Kays, S.J., Chinese chestnuts production in the United States Practice, problems and possible solutions, Econ. Botany, 37,187-200,1983. 

Andrews J. T., Domack E. W., Cunningham W. L., Leventer A., Light K. J., Jull A. J. T., Demaster D. J. and Jennings A. E. (1999) Problems and possible solutions concerning radiocarbon dating of surface marine sediments,... 

The synthesis, analysis, and evaluation of reaction paths is of fundamental importance in the chemical process industries. Research and development chemists and chemical engineers are often confronted with problems diich are best solved by utilizing chemical reactions. Figure I shows a matrix of the common problems and possible solutions encountered in the chemical process industries. Problems associated with products may be classified into those which deal with compounds or mixtures of compounds which are a new market for the company and those which are existing products. Separation problems which might be solved by chemical reactions (e.g. use chemical reactions to convert one or more of the species in a mixture... 

Pennell, J.F., "Alite Birefringence Measurement- Some Problems and Possible Solutions," Proceedings of the 9th International Conference on Cement Microscopy, International Cement Microscopy Association, Reno, Nevada, 1987, pp. 1-15. 

Skirving A.P. 1999. Total shoulder arthroplasty—current problems and possible solutions. 

THE FUTURE PROBLEMS AND POSSIBLE SOLUTIONS IN INSECT MIMICRY... 

Kaufmann A. Validation of multiresidue methods for veterinary drug residues related problems and possible solutions. Anal Chim Acta 2009 637(1—2) 144—55. 

Anune units must be designed to overcome these special problems. This chapter reviews both the causes of corrosion problems and possible solutions. It describes the locations within amine units where the various agents cause corrosion, discusses the corrosion mechanisms in these places, and reviews the design practices and preventive measures required to mitigate corrosion. These measures include control of velocities and inqiingement, process con-... 

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