Infrared Study of Benzaldehyde and 4-Substituted Benzaldehydes in Carbon Tetrachloride and/or Chloroform Solutions: Aldehydic CH Group

1992 ◽  
Vol 46 (2) ◽  
pp. 293-305 ◽  
Author(s):  
Richard A. Nyquist ◽  
Sam E. Settineri ◽  
Davin A. Luoma

The vCH and 2 δCH Fermi resonance doublet and unperturbed vCH and unperturbed 2 δCH for 4- x-benzaldehydes increase in frequency as the mole % CHCl3/CCl4 increases. One portion of the vCH and 2 δCH Fermi doublet occurs in the region 2726–2746 cm−1 and the other portion of the Fermi doublet occurs in the region 2805–2845 cm−1. The unperturbed vCH for 4- x-benzaldehydes is assigned in the region 2760–2810 cm−1. Submaxima are also noted for 4- x-benzaldehydes in the region 2726–2810 cm−1 and these bands are assigned to combination tones. The vasym. NO2 mode occurs in the region 1533.60–1538.73 cm−1 and the vsym. NO2 mode occurs in the region 1344.07–1345.63 cm−1 for 4-nitrobenzalde-hyde in CHCl3/CCl4 solutions. The vsym. NO2 mode shifts to lower frequency by ∼4.8 cm−1, while the vsym. NO2 mode shifts to higher frequency by ∼1.6 cm−1 in going from CCl4 solution to CHCl3 solution. The vCN mode for 4-cyanobenzaldehyde increases in frequency in a nonlinear manner as the mole % CHCl3/CCl4 increases. The vOH mode for 4-hydroxybenzaldehyde decreases in frequency in essentially a linear manner as the mole % CHCl3/CCl4 increases. The δCH mode for 4- x-benzaldehydes increases in frequency as the mole % CHCl3/CCl4 increases; however, neither unperturbed vCH nor δCH correlates with Hammett σp values.

1991 ◽  
Vol 45 (10) ◽  
pp. 1641-1648 ◽  
Author(s):  
Richard A. Nyquist ◽  
Sam E. Settineri ◽  
Davin A. Luoma

The carbonyl stretching mode of 4- x-benzaldehydes increases in frequency as the mole % CHCl3/CCl4 decreases and as the value of σP− or σRO for the 4- x atom or group increases. Other functional groups such as OH, NO2 and CN are also affected by interaction with the CHCl3 and/or CCl4 solvent system. Other solvents may interact differently with each functional group so that, say, vC=O vs. σP−, σRO, or solvent acceptor numbers (AN) may not correlate in a uniform manner in all solute/solvent systems.


1993 ◽  
Vol 47 (6) ◽  
pp. 677-686 ◽  
Author(s):  
R. A. Nyquist ◽  
C. W. Puehl

The νasym.NCS frequencies for alkyl isothiocyanates occur at higher frequency in CHCl3 or CDCl3 solution than in CCl4 solution. The νasym.NCS mode increases in frequency as the mole % CHCl3/CCl4 increases. The νasym.NCS mode for butyl isothiocyanate occurs at an exceptionally high frequency, and this result is explained in terms of the formation of a pseudo-six-membered intramolecularly hydrogen-bonded ring. The νasym.NCS modes for the alkyl isothiocyanates are corrected for Fermi resonance (FR), with the exception of the propyl analog. The propyl analog appears to have three other modes in FR with νasym.NCS, and an equation has not yet been developed to correct for FR in this case. The unperturbed νasym.NCS frequencies for alkyl isothiocyanates decrease in the alkyl order: methyl, butyl, ethyl, and tert-butyl. The decrease in frequency of νasym.NCS in the order methyl, ethyl, and tert-butyl isothiocyanate is attributed to weakening of the N=C=S bonds due to σ electron donation of each alkyl group. In the case of the butyl analog, the σ electron donation is partially compensated for by the postulated existence of a pseudo-six-membered hydrogen-bonded ring.


1992 ◽  
Vol 46 (2) ◽  
pp. 306-316 ◽  
Author(s):  
Richard A. Nyquist

The carbonyl stretching mode in some of the 4- x-benzaldehydes is in Fermi resonance with an overtone of a fundamental which occurs at lower frequency. In general, the unperturbed vC=O frequencies for 4- x-benzaldehydes do appear to correlate with the σp values of the 4- x atom or group. The AN values of the solvents show a pseudo-correlation with the carbonyl and vasym. NO2 stretch vibrations of 4- x-benzaldehyde. However, neither σp nor AN values appear to take into account solute/solvent interactions such as intermolecular hydrogen bonding with the C=O group and with other sites in the molecule such as the phenyl group π system and with the electronic system of other functional groups, since the points in each plot do not correlate in the exact manner in each case.


1949 ◽  
Vol 27b (2) ◽  
pp. 87-100 ◽  
Author(s):  
S. Barnartt ◽  
J. B. Ferguson

The isopiestic method has been applied to the sorption of carbon tetrachloride and water vapors by activated coconut shell charcoals. The isopiestic charges were found to be linearly related over wide pressure ranges. Isotherms formed by plotting the isopiestic charges of two charcoals one against the other consisted of three linear sections for both carbon tetrachloride and water. If the pressure isotherm of one charcoal be known, those of other charcoals may be computed from it by weighing relatively few isopiestic charges. Errors inherent in the measurement of equilibrium pressures, as well as those caused by the drift of the pressure isotherms towards higher sorption capacities at a given pressure, are eliminated in the isopiestic method of comparing charcoals. The linear relation between the isopiestic charges affords a simple criterion of rejection for equations proposed to fit the pressure isotherms. It also throws into relief the structural regularities in activated charcoals. The existence of discontinuities m the sorption process, reported by previous experimenters, is supported by the isopiestic data.


2021 ◽  
Vol 178 (1-2) ◽  
pp. 59-76
Author(s):  
Emmanuel Filiot ◽  
Pierre-Alain Reynier

Copyless streaming string transducers (copyless SST) have been introduced by R. Alur and P. Černý in 2010 as a one-way deterministic automata model to define transductions of finite strings. Copyless SST extend deterministic finite state automata with a set of variables in which to store intermediate output strings, and those variables can be combined and updated all along the run, in a linear manner, i.e., no variable content can be copied on transitions. It is known that copyless SST capture exactly the class of MSO-definable string-to-string transductions, and are as expressive as deterministic two-way transducers. They enjoy good algorithmic properties. Most notably, they have decidable equivalence problem (in PSpace). On the other hand, HDT0L systems have been introduced for a while, the most prominent result being the decidability of the equivalence problem. In this paper, we propose a semantics of HDT0L systems in terms of transductions, and use it to study the class of deterministic copyful SST. Our contributions are as follows: (i)HDT0L systems and total deterministic copyful SST have the same expressive power, (ii)the equivalence problem for deterministic copyful SST and the equivalence problem for HDT0L systems are inter-reducible, in quadratic time. As a consequence, equivalence of deterministic SST is decidable, (iii)the functionality of non-deterministic copyful SST is decidable, (iv)determining whether a non-deterministic copyful SST can be transformed into an equivalent non-deterministic copyless SST is decidable in polynomial time.


1971 ◽  
Vol 61 (2) ◽  
pp. 309-313 ◽  
Author(s):  
Ian McLure

Fifth-instar nymphs of Rhodnius prolixus Stålwere exposed to the vapours of 11 volatile drugs: acetone, bromobenzene, bromoform, carbon tetrachloride, chloral hydrate, chloroform, dioxane, ethanol, ethyl ether, isopropanol and paraldehyde. Bromobenzene, bromoform, carbon tetrachloride, chloroform and ether induced reversible anaesthesia. For each of these five, the insects exhibited a different andspecific pattern of motor responses before becoming totally immobile; these responses are described. The responses to carbon tetrachloride are similar to the normal feeding responses of this insect. The other six drugs did not induce anaesthesia, but instead, a commonand stereotyped pattern of cleaning responses, suggesting irritation of the sensory organs. It is proposed that the agent-specific responses to the anaesthesiainducing drugs are due to their differential action upon specific portions of the insect central nervous system.


2012 ◽  
Vol 33 (8) ◽  
pp. 812-816
Author(s):  
孙尚 SUN Shang ◽  
吴咏玲 WU Yong-ling ◽  
李硕 LI Shuo ◽  
蒋秀兰 JIANG Xiu-lan ◽  
孙成林 SUN Cheng-lin ◽  
...  

1968 ◽  
Vol 51 (6) ◽  
pp. 1175-1177 ◽  
Author(s):  
Robert M Hill ◽  
B D Hites

Abstract Very small particles of bone can be separated from ground meats and meat products by the following procedure: The bulk of the meat is solubilized by digestion with papain and the bone is separated from the other nondigestible material according to its ability to settle in a carbon tetrachloride: acetone mixture. Turkey samples with widely varying bone content were analyzed, with good agreement between duplicate samples.


2019 ◽  
Vol 38 (11) ◽  
pp. 1275-1282
Author(s):  
A Pergel ◽  
L Tümkaya ◽  
MK Çolakoğlu ◽  
G Demiral ◽  
S Kalcan ◽  
...  

Carbon tetrachloride (CCL4) is often employed in the production of chlorofluorocarbons, petroleum refining, oil and rubber processing, and laboratory applications. Oral, subcutaneous, and inhalation exposure to CCL4 in animal studies have been shown to be capable of leading to various types of cancer (benign and malignant, liver, breast, and adrenal gland tumors). The present study also evaluated the protective role of infliximab (INF) against the deleterious effects of CCL4 on the intestinal system. Twenty-four male Sprague-Dawley rats were randomly assigned into three groups, control ( n = 8), CCL4 ( n = 8), and CCL4 + INF ( n = 8). The control group received 1 mL isotonic saline solution only via intraperitoneal (i.p.) injection. The CCL4 group received a single i.p. dose of 2 mL/kg CCL4. The CCL4 + INF group received a single i.p. dose of 7 mg/kg INF followed 24 h later by a single dose of 2 mL/kg CCL4. All rats were euthanized 2 days following drug administration. CCL4 group samples also exhibited diffuse loss of enterocytes, vascular congestion, neutrophil infiltration, an extension of the subepithelial space and significant epithelial lifting along the length of the villi with a few denuded villous tips. In addition, CCL4 treatment increased intestinal malondialdehyde (MDA) level and caspase-3 positivity. On the other hand, INF decreased MDA levels, caspase-3 positivity, and loss of villous. Our findings suggest that CCL4 appears to exert a highly deleterious effect on the intestinal mucosa. On the other hand, INF is effective in preventing this CCL4-induced intestinal injury by reducing oxidative stress and apoptosis.


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