Analog scope

On a digital scope such as the TDS420/460 series, you may want to set it to display the waveform on average setting (maybe 10-20 waveforms superimposed), instead of the high-res or sample capture modes. It will create a fuzz similar to an analog scope. 

This is probably the best feature of digital scopes when it comes to troubleshooting switching power supplies. This is where they win hands down against analog scopes. This mode can be used to capture non-repetitive events such as... 

Although there is very little scope for reactions of the above types with 1,2-benzisoxazole derivatives, the quaternary salts such as 2-methyl-3-phenyl-l,2-benzisoxazolium salt underwent base-catalyzed isomerization to the 1,3-benzoxazine shown in Scheme 83. This reaction is analogous to the formation of (202) above (67AHC(8)277). 

Subsequently, Beals and Brown expanded the scope of the earlier work from their laboratory to include the tetraoxaquaterene derived from furan and 3-pentanone. Using 3,3-difurylpentane and diethyl ketone in the presence of dry hydrogen chloride gas, the all-ethyl analog of 6 (mp 249°) was obtained in 20% yield. ... 

Iodine azide, on the other hand, forms pure adducts with A -, A - and A -steroids by a mechanism analogous to that proposed for iodine isocyanate additions. Reduction of such adducts can lead to aziridines. However, most reducing agents effect elimination of the elements of iodine azide from the /mwj -diaxial adducts of the A - and A -olefins rather than reduction of the azide function to the iodo amine. Thus, this sequence appears to be of little value for the synthesis of A-, B- or C-ring aziridines. It is worthy to note that based on experience with nonsteroidal systems the application of electrophilic reducing agents such as diborane or lithium aluminum hydride-aluminum chloride may yet prove effective for the desired reduction. Lithium aluminum hydride accomplishes aziridine formation from the A -adducts, Le., 16 -azido-17a-iodoandrostanes (97) in a one-step reaction. The scope of this addition has been considerably enhanced by the recent... 

Though beyond the scope of this book, the carbocyclic analog of the Ciamician—Dennstedt reaction has been investigated. ... 

In 1999, Bob Atkinson wrote [1] that aziridination reactions were epoxida-tion s poor relation , and this was undoubtedly true at that time the scope of the synthetic methods available for preparation of aziridines was rather narrow when compared to the diversity of the procedures used for the preparation of the analogous oxygenated heterocycles. The preparation of aziridines has formed the basis of several reviews [2] and the reader is directed towards those works for a comprehensive analysis of the area this chapter presents a concise overview of classical methods and focuses on modern advances in the area of aziridine synthesis, with particular attention to stereoselective reactions between nitrenes and al-kenes on the one hand, and carbenes and imines on the other. 

Although amine oxides are also beyond the scope of this volume, they are included here because of their analogy to amphoterics. Amine oxides derived from alkylbenzenes were prepared as follows [21] ... 

The reaction is similar to the Diels-Alder (in action, not in scope), and if dienes are involved, the latter reaction may compete, though most alkenes react with a diene either entirely by 1,2 or entirely by 1,4 addition. Three mechanisms can be proposed analogous to those proposed for the Diels-Alder reaction. Mechanism... 

Carroll SS, Olsen DB (2006) Nucleoside analog inhibitors of hepatitis C vims rephcation. Infect Disord Dmg Targets (Formerly Current Drag Targets - Infectious) 6 17-29 CasteU JV, lover R, Martinez-Jimenez CP, Gomez-Lechon MJ (2006) Hepatocyte cell lines their use, scope and limitations in dmg metabolism studies. Expert Opin Drag Metab Toxicol 2 183-212... 

The Auger effect is analogous to the internal conversion in that an atomic electron is emitted instead of the expected X-ray. Very little is well known about Auger yields in these transitions out beyond the K shell, and a more detailed discussion is outside the scope of this review. 

In contrast to the related organoboranes, which are mostly used in the addition to non-polar carbon-carbon multiple bonds, aluminum hydrides have found their widest use in organic synthesis in the addition reaction to polar carbon-carbon and carbon-heteroatom multiple bonds including carbonyl, nitrile and imino groups as well as their a,(J-unsaturated analogs. Although these reduction reactions are also sometimes referred as hydroalumination reactions in the Hterature, they are outside the scope of this review. 

The sensitivity achieved (LOD) is not normally presented. It is recognized that different laboratories determine dissimilar values for this parameter and even within a laboratory the repeatability of the LOD is low. Most often, the lowest validated concentration gives an impression about the lowest levels that can be analyzed generally with acceptable results. A measure of selectivity is the intensity of blank results. This intensity is discussed by the participants of inter-laboratory validation studies. However, results are not reported and limits are not defined by CEN TC 275. The results of method validations of the several multi-residue/multi-matrix methods are not reported in the same way, but newer methods with limited scope generate analogous tables with validation results (as an example, see Table 7). 

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