CASE program

Drilling Vessels 1357. Marine Riser Systems. 1359. Casing Programs 1361. Well Control 1363. 

Coppes, J., Casing Programming, The Norwegian Institute of Technology, Trondheim, 19XX. 

Comment-. All models yield the same l-value, but differ in the number of degrees of freedom to be used. The difference between the means is barely significant in two cases. Suggestion acquire more data to settle the case. Program TTEST automatically picks the appropriate equation(s) and displays the result(s). Equation (1.21) is used to scan the parameter space (Xmean Sx, n) in the vicinity of the true values to determine whether a small change in experimental protocol (n) or measurement noise could have changed the interpretation from Hq to H or vice versa. 

The final log P model was obtained by correlahng a total of 94 parameters with the logP values through MLR analysis. Correchon fragments idenhfied by the CASE program can be classified into four categories (i) tautomerization effects,... 

The ADEQUATE data were combined with GCOSY, HSQC, - C, and 1H-15N GHMBC data as input for the COCON CASE program. Four different data sets were prepared as input for the program. Data set A was comprised of the correlations from the GCOSY and 1H-13C GHMBC spectra. Data set B contained the same data as A supplemented by the... 

As a part of a further investigation of the impact of 1,1-ADEQUATE data on CASE programs, Cheatham and co-workers46 employed retrorsine (22) and delcosine (23) as model compounds. HMBC and 1,1-ADEQUATE data were acquired for 22 and a suite of HMBC, H2BC, and 1,1-ADEQUATE spectra were acquired for 23. Usefully, the authors also reported details of their efforts to optimize the acquisition of the 1,1-ADEQUATE data used as input for the CASE investigation. Strychnine (1) was used by the authors to explore the optimization of experimental conditions. Using a 600-MHz instrument equipped with a 5-mm cryoprobe, the authors compared s/n for various 1,1-ADEQUATE correlations of strychnine using 10 mg samples in 5 mm tubes, and both 5 and 2.5 mg samples in 3 mm tubes. Acquisition times of 15 h were used for these measurements. 

The authors work demonstrated that even samples as small as 2.5 mg could be studied yielding data with s/n > 5 1. They further demonstrated for samples with aromatic rings that 60 Hz optimization of the experiment was beneficial and that correlations to aliphatic carbons with smaller LJcc couplings did not experience a serious adverse impact due to the larger optimization but the reverse was not true. Correlations to aromatic carbons were not amenable to optimization biased toward aliphatic carbons (e.g. 40 Hz). Correlations observed in the 1,1-ADEQUATE spectrum of retrorsine (22) are shown on the structure. Complete 1,1-ADEQUATE correlations were not shown for delcosine (23) but the authors noted that the key correlations shown on the structure that were observed in the 1,1-ADEQUATE data were not observed in the H2BC spectrum acquired. The impact of the availability of the 1,1-ADEQUATE data on the Structure Elucidator CASE program is discussed in Section 7. 

To date, there have been four reports published that have examined the impact of 1,1-ADEQUATE correlation data on structure generation times and the number of structures generated for various CASE programs.46 47 53 55 The first of the studies discussed above used limited 1,1-ADEQUATE data in a COCON computation rim for the relatively simple molecule 4,5-dibromopyrrol-2-carboxylic acid (4).53 In the same report, the authors considered the effect of 1,1-ADEQUATE correlations that would theoretically be expected for manzacidin A (5), however no 1,1-ADEQUATE data were actually acquired. The results for 4 and 5 are summarized in Table 2. 

The most recent report of Myer and Kock47 afforded a more robust assessment of the value of 1,1-ADEQUATE data as a part of the input data set for the COCON CASE program. The output of the structure generation for the brominated phakellins (18a, b) and brominated isophakellin (19a, b) alkaloids is summarized in Table 3. Structures generated without specified hybridization are noted on the first line for each compound that can be compared with the number of structures generated when pre-defined hybridization was employed on the second line for each... 

Of course, it is lrequently desirable to utilize a controlled directional drilling technique. There are several reasons, as indicated by Fig. 15. The three most commonly patterned directional holes are shown in Fig. 16. The planned course of direction depends upon several factors, including rig capacity, hole size, mud program, types of formation, and the casing program. Meticulous surveying is required to achieve the desired results. Several types of drilling tools may be required. 

Klopman, G., D.M. Balthasar, and H.S. Rosenkranz. 1993. Application of the computer automated structure evaluation (CASE) program to the study of structure biodegradation relationships of miscellaneous chemicals. Environ. Toxicol. Chem. 12 231-240. 

Nuzillard and coworkers [44] also reported the application of the LSD CASE program to the elucidation of the structure of acosmine acetate (4) in 1999. The... 

Tab. 14.2 Impact of information content on the application of the COCON CASE program for the elucidation of the structure of oroidin (3).

Martin, G. E. and Williams, A. J. (March 7-8, 2002) Probes, Pulse Sequences, and CASE Programs Advances in the Characterization of Novel Structures Using NMR-Based Methods. ACD/Labs North American User s Meeting, Princeton, NJ. 

The limiting values of indices may be freely modified by the user as described in TREOR s manual, while the sequence of peaks in the basis set may only be changed to a certain extent as described in the footnotes to Table 5.20. In the majority of cases, program defaults work quite well and any changes in them should be attempted only when no acceptable solution has been found. 

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