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CD data and

The 2,4-rr r-4-arylflavans, myristinins A (20) and D (23), were also obtained from Knema elegans Hecht and his coworkers demonstrated that these compounds were the most potent DNA polymerase f3 inhibitors to date. The same authors also settled the 2S,4R) absolute configuration for both (20) and (23) using CD data, and confirmed such an assignment via total synthesis of (+)-myristinin A (20) (Scheme 3). ... [Pg.611]

Three neolignans (15, 16 and 17) were isolated from the wood of A. sachalinensis, and their structure was elucidated by spectroscopic analyses, they were identified with 2,3-dihydro-2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-5-(2-formylvinyl)-7-hydroxybenzofuran (15), 2,3-dihydro-2-(4-hydroxy-3-methoxyphenyl)-3-(p-coumaroyloxymethyl)-5-co-hydroxypropyl-7-hydroxybenzofuran (16) and 1-(4-hydroxy-3-methoxyphenyl)-2-[4-(2-formylvinyl)-2-methoxy-phenoxy]-propane-1,3-diol (17). The absolute configurations of the former two neolignans (15) and (16) have been demonstrated, using CD data and shifts (ref. 20). [Pg.620]

Commercial instruments have been modified to make possible the simultaneous recording of linear absorption and CD data and to facilitate work on turbid preparations (Kfivacic et ai, 1971). Also, a prototype spectrophotometer for simultaneous measurement of ORD, CD, and linear absorbance has been described (Amato and Ewing, 1974). A Roussel-Jouan Dichrograph was modified to permit the direct reading of A and A /2 (Snatzke and Lohr, 1968). The sensitivity of a commercial CD instrument was improved by a factor of 10-12 by the use of a time-averaging system (Myer and MacDonald, 1967 Horwitz et al, 1968). Fourier transform spectrometry was applied to CD (Stewart, 1971). The fundamental aspects of its application were described, but no information was given about the performance. [Pg.170]

So far we have introduced several methods to interpret CD data and have explained applications of CD spectroscopy to various supermolecules such as polymers, liquid crystals, micelles, metal complexes, and nanoparticles. In this section the applications of CD to a broader range of supermolecules are briefly summarized. [Pg.466]

Configurations of the four triterpene epo lactones, 3-oxo-, 29-nor-3-OXO-, 3p-aceto Q - and 3p-hydro g -7p,8p-epo g -5a-lanost-24-en-30,9a-olides isolated from a Penares sp. sponge collected from Vietnamese waters have been established by Kolesnikova et by the use of vicinal proton-proton couplings, NOESY and CD data, and confirmed by X-ray ciystallographic analysis of 29-nor-3-oxo-7p,8p-epo g -5a-lanost-24-en-30,9a-olide. [Pg.223]

These tests generate several Gigabytes of data that are fed into a historical database. Although most of the analysis is performed automatically, human interaction is still needed to compare current and past data. Data are stored on optical CD S s from which the historical data bank are retrieved during field inspections from a mobile unit. Each of these is equipped with a CD-jukebox linked to an analysis station. The jukebox can handle 100 CD s, enough to store all previously recorded data. A dedicated software pre-fetches the historical data and compares it on-line with the newly acquired NDT-data. It is based on fuzzy algorithms applied to signal features. [Pg.1022]

The experimental data and arguments by Trassatti [25] show that at the PZC, the water dipole contribution to the potential drop across the interface is relatively small, varying from about 0 V for An to about 0.2 V for In and Cd. For transition metals, values as high as 0.4 V are suggested. The basic idea of water clusters on the electrode surface dissociating as the electric field is increased has also been supported by in situ Fourier transfomr infrared (FTIR) studies [26], and this model also underlies more recent statistical mechanical studies [27]. [Pg.594]

The CD-I (compact disk-interactive) is a low cost alternative to the CD-ROM for the entertainment industry. CD-I is a subset of the CD-ROM standard data format. It allows the digital storage of data, audio, and video information in a form that permits rapid interaction with a computer. CD-I is compatible to CD-ROM and to CD-AD 0 = 120 mm. The definition of the CD-I format is put down in the Green Book (Philips/Sony). [Pg.139]

The principal use of CD-ROM and WORM disks is essentially substitution of data storage on paper or microfiche. Conservative estimates number the worldwide use for data storage by paper at 91%, microfiche at 4%, and in electronic media at 5%, of which 4% are magnetic and 1% optical media (18). CD-ROM is being used as an electronic counterpart to print media the WORM disk presents itself more and more as a substitute for paper to store archivable, forgery-proof documents. [Pg.142]

There is no competitive situation for data storage disks with embossed iaformation (CD-ROM) and recordable/nonerasable disks (WORM) no counterpart to CD-ROM and WORM exists among magnetic memories. EOD drives are best compared to floppies and removable hard disk media given their possibiUty of easy and problem-free disk exchange and a capacity on the order of that of removable magnetic media (Tape, Bernoulli, SyQuest). [Pg.164]

The acceptance of optical data storage iato the mass storage market, which is as yet exclusively dominated by magnetic systems, will be fundamentally boosted if optical drives and media are subject to uniform standards and become fully compatible, and multiuser drives are offered which enable the user to employ alternatively CD-ROM and EOD disks, and maybe WORM disks as well (and CD-R disks, respectively). A prerequisite, however, will be whether rewritable optical memories will use the MOR or the PCR process. This accord especially will be hard to reach. [Pg.164]

The substance chaetochromin A, structure A, has been shown by X-ray dif action to have the absolute configuration indicated in the structure. The CD spectra of A and the related compounds cephalochromin (B) and ustilaginoidin (C) are shown in the figure. Deduce the absolute stereochemistry of cephalochromin and ustilaginoidin trom these data, and draw perspective structures indicating the absolute configuration. [Pg.117]

The NMR study of steroidal epoxides (discussed in section II-F) parallels that of the analogous thiiranes. It is possible to relate the location and configuration of the thiirane group with the angular methyl and thiirane proton resonances. The proton NMR relationships for the intermediate thiocyanatohydrins have been included inageneral NMR study of steroids. Electronic spectra may be used in the analysis of steroidal thiiranes. Spectroscopic measurements have shown the existence of a low intensity absorption in the 240-260 m region. The regular patterns of rotatory contributions of thiiranes which are comparable with those of ketones prompted an accumulation of ORD and CD data for steroidal thiiranes. [Pg.42]

Contains information drawn from data compiled by the National Toxicology Program (NTP), which coordinates and provides information about potentially toxic chemicals with potential for human exposure to regulatoiy and research agencies. Contains information on 2,280 chemicals drawn from literature. The records closely resemble an MSDSformat. Print, CD-ROM and online interactive versions available from the Coast Guard and commercial sources. [Pg.305]

TFe data of Popov et alm for Ag contradict the above sequence. They found that pentanol adsorbed more strongly on Ag(100) than on Ag(l 11). Similarly, Cd(0001) adsorbs less strongly than pc-Cd.661 The data for Sb and Bi are to some extent contradictory since the trend is broadly correct but with scatter, which is attributed to the crystal face specificity of space-charge effects.153 For instance, adsorption of cyclohexanol on Bi conforms to the sequence (011) > (101) > (211) > (001) >(111), while the capacitance at a - Ovaries in the sequence (001) > (011) > (211) > (101) > (111). Thus only the faces (001), (211), and (111) are in the expected order. Surprisingly, the Cd data of Lust etal. show similarities with those of Naneva etal.,212 although capacitances disagree. Thus the order of cyclohexanol adsorbability is (1010) > (0001) while the capacitance varies in the order (1010) > (1120) > (0001), i.e., the other way round. In these cases one might wonder whether the G(M-B) term is really independent of face. [Pg.188]

Chitosan (> 75% deacelylation, 800-2000 cps) was mixed wilh stock so-lulions of Cu(II), Fe(ll), Cd(ll) and Zn(II), prepared in 0.1 M HNO3, and of Ca(ll) and Mn(II), in 0.1 MHCl. It was found that, in the chelation of most metal ions by chitosan, 1 1 binding of chitosan is more dominant than 2 1 cooperative binding, but vice versa for Zn(II) and Cd(II). The chelation of Cu(II) by chitosan showed much higher reactivity when compared to other divalent metal ions. Cu(II), Fe(II), Cd(II) andZn(II) showed strong reactivity and stability of their chelates. In contrast, the interactions between Ca(II) or Mn(II) and chitosan were almost negligible. These data confirm brilliantly previous data by Muzzarelli et al. [116]. [Pg.163]

Optically active molecules show circular dichroism. Their extinction coefficients f l and are different and change as a function of wavelength. Using a suitable spectroelectrochemical cell, Af = fl -which is usually small compared to conventional extinction coefficients, can be measured. Combined with the special properties of a thin layer cell kinetic data can be extracted from CD-data [01 Liu]. (Data obtained with this method are labelled CD.)... [Pg.274]

Fig. 3.1 Model of CdS deposition and recrystaUization. The changes in film structure are related to the features of the cyclic voltammogram and the capacitance plot broken line). The interpretation of the capacitance data in this way leads to a mean value of ffcds = 17 for the relative permittivity of the film. (Reprinted from [34], Copyright 2009, with permission from Elsevier)... Fig. 3.1 Model of CdS deposition and recrystaUization. The changes in film structure are related to the features of the cyclic voltammogram and the capacitance plot broken line). The interpretation of the capacitance data in this way leads to a mean value of ffcds = 17 for the relative permittivity of the film. (Reprinted from [34], Copyright 2009, with permission from Elsevier)...
Some data submitters were concerned about whether the supplemental files would be archived along with the data, and whether the supplemental files would be subject to Freedom of Information Act (FOIA) requests. OPP expects to maintain the CD provided as the electronic data submission, and archive the supplemental files on CD along with the rest of the electronic data submission. However, the official archive format at the present time is paper, and the supplemental files duplicate material in the paper submission. Supplemental files may be released upon FOIA requests after the first registration for the pesticide active ingredient, subject to the requirements of FIFRA 10(g), which include an affirmation statement from the requestor and a notice to the data owner, and exclude any FIFRA CBI. [Pg.1070]


See other pages where CD data and is mentioned: [Pg.112]    [Pg.748]    [Pg.145]    [Pg.103]    [Pg.103]    [Pg.116]    [Pg.54]    [Pg.112]    [Pg.748]    [Pg.145]    [Pg.103]    [Pg.103]    [Pg.116]    [Pg.54]    [Pg.96]    [Pg.228]    [Pg.154]    [Pg.459]    [Pg.3]    [Pg.88]    [Pg.705]    [Pg.594]    [Pg.403]    [Pg.171]    [Pg.62]    [Pg.218]    [Pg.56]    [Pg.57]    [Pg.61]    [Pg.610]    [Pg.165]    [Pg.1063]    [Pg.661]    [Pg.333]    [Pg.1152]    [Pg.1262]    [Pg.1269]    [Pg.1277]   
See also in sourсe #XX -- [ Pg.9 ]




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