Journal articles: 'Reactive molecules'

1

Krasowski, Matthew D., Mohamed G. Siam, Manisha Iyer, Anthony F. Pizon, Spiros Giannoutsos, and Sean Ekins. "Chemoinformatic Methods for Predicting Interference in Drug of Abuse/Toxicology Immunoassays." Clinical Chemistry 55, no. 6 (June 1, 2009): 1203–13. http://dx.doi.org/10.1373/clinchem.2008.118638.

Full text

Abstract:

Abstract Background: Immunoassays used for routine drug of abuse (DOA) and toxicology screening may be limited by cross-reacting compounds able to bind to the antibodies in a manner similar to the target molecule(s). To date, there has been little systematic investigation using computational tools to predict cross-reactive compounds. Methods: Commonly used molecular similarity methods enabled calculation of structural similarity for a wide range of compounds (prescription and over-the-counter medications, illicit drugs, and clinically significant metabolites) to the target molecules of DOA/toxicology screening assays. We used various molecular descriptors (MDL public keys, functional class fingerprints, and pharmacophore fingerprints) and the Tanimoto similarity coefficient. These data were then compared with cross-reactivity data in the package inserts of immunoassays marketed for in vitro diagnostic use. Previously untested compounds that were predicted to have a high probability of cross-reactivity were tested. Results: Molecular similarity calculated using MDL public keys and the Tanimoto similarity coefficient showed a strong and statistically significant separation between cross-reactive and non–cross-reactive compounds. This result was validated experimentally by discovery of additional cross-reactive compounds based on computational predictions. Conclusions: The computational methods employed are amenable toward rapid screening of databases of drugs, metabolites, and endogenous molecules and may be useful for identifying cross-reactive molecules that would be otherwise unsuspected. These methods may also have value in focusing cross-reactivity testing on compounds with high similarity to the target molecule(s) and limiting testing of compounds with low similarity and very low probability of cross-reacting with the assay.

APA, Harvard, Vancouver, ISO, and other styles

2

FAHRENDORF, SARAH, FRANK MATTHES, DANIEL E. BÜRGLER, CLAUS M. SCHNEIDER, NICOLAE ATODIRESEI, VASILE CACIUC, STEFAN BLÜGEL, CLAIRE BESSON, and PAUL KÖGERLER. "STRUCTURAL INTEGRITY OF SINGLE BIS(PHTHALOCYANINATO)-NEODYMIUM(III) MOLECULES ON METAL SURFACES WITH DIFFERENT REACTIVITY." SPIN 04, no. 02 (June 2014): 1440007. http://dx.doi.org/10.1142/s2010324714400074.

Full text

Abstract:

Magnetic molecules are auspicious candidates to act as functional units in molecular spintronics. Integrating molecules into a device environment providing mechanical support and electrical contacts requires their deposition as intact entities onto substrates. Thermal sublimation is a very clean deposition process that, however, thermally decomposes molecules of insufficient stability leading to the deposition of molecular fragments. Here, we show that the molecule-surface interaction of chemisorbed molecules affects the intramolecular bonding and can lead depending on the surface reactivity to either molecular decomposition or enhanced stability. We study the integrity of single bis(phthalocyaninato)-neodymium(III) molecules ( NdPc 2) deposited by sublimation on differently reactive surfaces, namely Au (111), Cu (100), and two atomic layers of Fe on W (110), on the single molecular level by scanning tunneling microscopy (STM) and spectroscopy. We find a strongly substrate-dependent tendency of the NdPc 2 molecules to decompose into two Pc molecules. Surprisingly, the most reactive Fe / W (110) surface shows the lowest molecular decomposition probability, whereas there are no intact NdPc 2 molecules at all on the least reactive Au (111) surface. We attribute these findings to substrate-dependent partial charge transfer from the substrate to the Pc ligands of the molecule, which strengthens the intramolecular bonding mediated predominantly by electrostatic interaction.

APA, Harvard, Vancouver, ISO, and other styles

3

Mestdagh, J. M., C. Alcaraz, J. Berlande, J. Cuvellier, T. Gustavsson, P. Meynadier, P. De Pujo, O. Sublemontier, and J. P. Visticot. "Reaction Dynamics of Electronically Excited Barium Atoms With Free Molecules and Molecular Clusters." Laser Chemistry 10, no. 5-6 (January 1, 1990): 389–403. http://dx.doi.org/10.1155/1990/36585.

Full text

Abstract:

In this review article we describe some recent results obtained in our laboratory. The successful combination of crossed molecular beam techniques and various laser excitation schemes has been used to study chemiluminescent reactions of ground and excited electronic states of barium with free molecules and molecular clusters. Studies include the identification of reaction products in cases where many chemiluminescent reaction channels are opened. The case of Ba(6sp1P1,6s5d1D2,6s5d3Dj) reacting with H20, methanol, ethanol, propanol-1, propanol-2, methyl-2, propanol-2, butanol-l, allyl alcohol, dimethyl ether, diethyl ether and diallyl ether is examined. A reaction mechanism is proposed which accounts for all these reactions. Studies reported in this review also include the unravelling of reaction dynamics where various forms of energy are mixed (electronic and kinetic energy). This is shown in studies of Ba(1D2and1P1)+O2 reactions. Finally the role of molecular clusters as reactant is examined. Evidence is provided that clusters of N20, H20 and CO2, in collision with Ba(1S0and1P1)+O2, do not lead efficiently to both reactive and non reactive luminescent exit channels.

APA, Harvard, Vancouver, ISO, and other styles

4

Meuwly, Markus. "Reactive molecular dynamics: From small molecules to proteins." Wiley Interdisciplinary Reviews: Computational Molecular Science 9, no. 1 (August 24, 2018): e1386. http://dx.doi.org/10.1002/wcms.1386.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Matsuda, Kyle, Luigi De Marco, Jun-Ru Li, William G. Tobias, Giacomo Valtolina, Goulven Quéméner, and Jun Ye. "Resonant collisional shielding of reactive molecules using electric fields." Science 370, no. 6522 (December 10, 2020): 1324–27. http://dx.doi.org/10.1126/science.abe7370.

Full text

Abstract:

Full control of molecular interactions, including reactive losses, would open new frontiers in quantum science. We demonstrate extreme tunability of ultracold chemical reaction rates by inducing resonant dipolar interactions by means of an external electric field. We prepared fermionic potassium-rubidium molecules in their first excited rotational state and observed a modulation of the chemical reaction rate by three orders of magnitude as we tuned the electric field strength by a few percent across resonance. In a quasi–two-dimensional geometry, we accurately determined the contributions from the three dominant angular momentum projections of the collisions. Using the resonant features, we shielded the molecules from loss and suppressed the reaction rate by an order of magnitude below the background value, thereby realizing a long-lived sample of polar molecules in large electric fields.

APA, Harvard, Vancouver, ISO, and other styles

6

He, Mingyuan, Chenwei Lv, Hai-Qing Lin, and Qi Zhou. "Universal relations for ultracold reactive molecules." Science Advances 6, no. 51 (December 2020): eabd4699. http://dx.doi.org/10.1126/sciadv.abd4699.

Full text

Abstract:

The realization of ultracold polar molecules in laboratories has pushed physics and chemistry to new realms. In particular, these polar molecules offer scientists unprecedented opportunities to explore chemical reactions in the ultracold regime where quantum effects become profound. However, a key question about how two-body losses depend on quantum correlations in interacting many-body systems remains open so far. Here, we present a number of universal relations that directly connect two-body losses to other physical observables, including the momentum distribution and density correlation functions. These relations, which are valid for arbitrary microscopic parameters, such as the particle number, the temperature, and the interaction strength, unfold the critical role of contacts, a fundamental quantity of dilute quantum systems, in determining the reaction rate of quantum reactive molecules in a many-body environment. Our work opens the door to an unexplored area intertwining quantum chemistry; atomic, molecular, and optical physics; and condensed matter physics.

APA, Harvard, Vancouver, ISO, and other styles

7

Lei, Ning Ning, Na Zhong, Yi Dong Shi, and Xiao Rui Ling. "Researches on the Fixation Performance of Chitosan and its Derivative." Advanced Materials Research 535-537 (June 2012): 1547–51. http://dx.doi.org/10.4028/www.scientific.net/amr.535-537.1547.

Full text

Abstract:

The fixing performance of chitosan hydrochloride (CSH) with different molecular weight and chitosan biguanide hydrochloride (CSGH) as a fixing agent for cotton fabric dyed with reactive dyes was discussed. The results showed that the fixing effects of CSH on reactive dyes were related to its molecular weight, and the CSH with high molecular weight (HMW) exhibited better fixing effects than that with low molecular weight (LMW). The fixing effects of CSGH on reactive dyes were superior to that of the CSH with HMW, because of the CSGH molecule with positive charges and the imino groups, which could further strengthened the interaction among the CSGH, dyes and cellulose molecules. After treated by the CSGH, the soaping, perspiration and dry rubbing fastness of the dyed fabrics could be increased 0.5 to 1 grade, while the wet rubbing fastness of ones was also improved obviously. The infrared spectrum (FTIR) of the dyed fabric treated by CSGH showed that a cross-linking was formed among CSGH, dyes and cellulose molecules.

APA, Harvard, Vancouver, ISO, and other styles

8

Hopf, Henning. "Incarcerated Atoms and Reactive Molecules." Angewandte Chemie International Edition in English 30, no. 9 (September 1991): 1117–18. http://dx.doi.org/10.1002/anie.199111171.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

MLINARIC-MAJERSKI, K., and S. HIRSL-STARCEVIC. "ChemInform Abstract: Reactive Molecules - Carbenes." ChemInform 22, no. 16 (August 23, 2010): no. http://dx.doi.org/10.1002/chin.199116316.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Si, Yu Kun, Jian Feng Zhou, Li Yuan Qu, Ling Zhong, Feng Xiu Zhang, and Guang Xian Zhang. "The Interaction between Reactive Dye and Octyl Trimethyl Ammonium Chloride." Advanced Materials Research 781-784 (September 2013): 2712–15. http://dx.doi.org/10.4028/www.scientific.net/amr.781-784.2712.

Full text

Abstract:

Octyl trimethyl ammonium chloride (OTMAC) is a very efficient accelerant for reactive dyes on dyeing silk. In order to understand the accelerating mechanism, the interaction between dye molecules and OTMAC molecule was studied in this paper. The results showed that the DTMAC made the dye molecules assembled and the particle size of dye assemblages could reach to more than 500nm. The assembling of dye molecules leads to increase of the maximum absorption wavelength of dye. The higher the temperature is, the weaker the interaction between dye molecule and accelerant.

APA, Harvard, Vancouver, ISO, and other styles

11

Tao, Feng. "Nanoscale surface chemistry in self- and directed-assembly of organic molecules on solid surfaces and synthesis of nanostructured organic architectures." Pure and Applied Chemistry 80, no. 1 (January 1, 2008): 45–57. http://dx.doi.org/10.1351/pac200880010045.

Full text

Abstract:

This article briefly reviews the interplay of weak noncovalent interactions involved in the formation of self-assembled monolayers of organic molecules and the strong chemical binding in directed-assembly of organic molecules on solid surfaces. For a self-assembled monolayer, each molecule involves at least three categories of weak interactions, including molecule-substrate interactions, molecule-molecule interactions in a lamella, and molecule-molecule interactions between two adjacent lamellae. Basically, molecule-substrate interactions play a major role in determining molecular configuration. Molecule-molecule interactions, particularly the interactions of molecular ending functional groups between two adjacent lamellae, such as hydrogen bonds, play a dominant role in determining the molecular packing pattern in a monolayer. These weak interactions may induce or influence molecular chirality. This understanding at the atomic scale allows us to design 2D nanostructured organic materials via precisely manipulating these weak noncovalent interactions. Compared to the self-assembled monolayer formed via weak noncovalent interactions, the structure of directed-assembled monolayer/multilayers formed through strong chemical bonds is significantly dependent on the geometric arrangement and reactivity of active sites on the solid surface. In contrast to the significant role of weak intermolecular interactions in determining molecular packing in a self-assembled monolayer, strong chemical binding between molecules and reactive sites of a substrate plays a major role in determining the molecular packing pattern in a directed-assembly monolayer. Controllable chemical attachment between organic functional groups and reactive sites of the solid surface is crucial for the formation of a highly oriented organic monolayer and the following multilayer.

APA, Harvard, Vancouver, ISO, and other styles

12

Ruan Wen, Luo Wen-Lang, Zhang Li, Zhu Zheng-He, and Fu Yi-Bei. "Asymmetry of molecular reactive collision of the DTO molecules." Acta Physica Sinica 58, no. 3 (2009): 1537. http://dx.doi.org/10.7498/aps.58.1537.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Landerville, A. C., I. I. Oleynik, and C. T. White. "Reactive Molecular Dynamics of Hypervelocity Collisions of PETN Molecules." Journal of Physical Chemistry A 113, no. 44 (November 5, 2009): 12094–104. http://dx.doi.org/10.1021/jp905969y.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Assowe, O., Olivier Politano, Vincent Vignal, Patrick Arnoux, and B. Diawara. "A Reactive Force Field Molecular Dynamics Simulation Study of Corrosion of Nickel." Defect and Diffusion Forum 323-325 (April 2012): 139–45. http://dx.doi.org/10.4028/www.scientific.net/ddf.323-325.139.

Full text

Abstract:

The interaction of water molecules on a nickel surface was studied using ReaxFF (reactive force field) molecular dynamics.This approach was originally developed by van Duinet al.to study the hydrocarbon chemistry and the catalytic properties of organic compounds. To our knowledge, this method has not been used to study the corrosion processes of nickel exposed to water, which is what we set out to achieve in the present investigation. To do so, calculations were first performed using ReaxFF in order to reproduce certain well-known properties of pure nickel and nickel-water systems. This allowed us to study the adsorption of a single water molecule interacting with an optimized nickel surface. We also investigated the interaction of 405 molecules of water (ρ=0.99 g.cm-3) on the (100), (110) and (111) surfaces of a single crystal of nickel at 300 K. The results show that a water bilayer is adsorbed on nickel surfaces: the first water layer is directly bonded to the surface, whereas the molecules in the first and second layers are held together by hydrogen bonds.

APA, Harvard, Vancouver, ISO, and other styles

15

Huang, Zhen, and Roman Boulatov. "Chemomechanics with molecular force probes." Pure and Applied Chemistry 82, no. 4 (March 31, 2010): 931–51. http://dx.doi.org/10.1351/pac-con-09-11-36.

Full text

Abstract:

Chemomechanics is an emerging area at the interface of chemistry, materials science, physics, and biology that aims at quantitative understanding of reaction dynamics in multiscale phenomena. These are characterized by correlated directional motion at multiple length scales—from molecular to macroscopic. Examples include reactions in stressed materials, in shear flows, and at propagating interfaces, the operation of motor proteins, ion pumps, and actuating polymers, and mechanosensing. To explain the up to 1015-fold variations in reaction rates in multiscale phenomena—which are incompatible within the standard models of chemical kinetics—chemomechanics relies on the concept of molecular restoring force. Molecular force probes are inert molecules that allow incremental variations in restoring forces of diverse reactive moieties over hundreds of piconewtons (pN). Extending beyond the classical studies of reactions of strained molecules, molecular force probes enable experimental explorations of how reaction rates and restoring forces are related. In this review, we will describe the utility of one such probe—stiff stilbene. Various reactive moieties were incorporated in inert linkers that constrained stiff stilbene to highly strained macrocycles. Such series provided the first direct experimental validation of the most popular chemomechanical model, demonstrated its predictive capabilities, and illustrated the diversity of relationships between reaction rates and forces.

APA, Harvard, Vancouver, ISO, and other styles

16

Asnicar, Daniele, Emanuele Penocchio, and Diego Frezzato. "Sample size dependence of tagged molecule dynamics in steady-state networks with bimolecular reactions: Cycle times of a light-driven pump." Journal of Chemical Physics 156, no. 18 (May 14, 2022): 184116. http://dx.doi.org/10.1063/5.0089695.

Full text

Abstract:

Here, steady-state reaction networks are inspected from the viewpoint of individual tagged molecules jumping among their chemical states upon the occurrence of reactive events. Such an agent-based viewpoint is useful for selectively characterizing the behavior of functional molecules, especially in the presence of bimolecular processes. We present the tools for simulating the jump dynamics both in the macroscopic limit and in the small-volume sample where the numbers of reactive molecules are of the order of few units with an inherently stochastic kinetics. The focus is on how an ideal spatial “compartmentalization” may affect the dynamical features of the tagged molecule. Our general approach is applied to a synthetic light-driven supramolecular pump composed of ring-like and axle-like molecules that dynamically assemble and disassemble, originating an average ring-through-axle directed motion under constant irradiation. In such an example, the dynamical feature of interest is the completion time of direct/inverse cycles of tagged rings and axles. We find a surprisingly strong robustness of the average cycle times with respect to the system’s size. This is explained in the presence of rate-determining unimolecular processes, which may, therefore, play a crucial role in stabilizing the behavior of small chemical systems against strong fluctuations in the number of molecules.

APA, Harvard, Vancouver, ISO, and other styles

17

Fang, Jiarui, Ziheng Li, Xiruo Bai, Yichu Zhang, Jiahui Liu, Dan Wang, and Ye Yao. "Co2+ Doping and Molecular Adsorption Behavior of Anatase TiO2 (001) Crystal Plane." Catalysis Research 2, no. 3 (May 10, 2022): 1. http://dx.doi.org/10.21926/cr.2203018.

Full text

Abstract:

TiO2 (001) crystal plane exhibits molecular adsorption and photocatalytic activity. The loading capacity of reactive oxygen species present on crystal planes helps in the significant improvement of catalytic activity. The methods of synthesis and conditions of existence significantly affect the molecular adsorption properties of crystal planes, which in turn affects the ability of the system to load reactive oxygen species. Herein, we report the simulation of the molecular adsorption behavior on the TiO2 (001) using the density functional theory technique. The results show that the crystal plane doped with Co2+ produces an oxygen defect and chemisorbs O2 molecules present in the vicinity. Under conditions of adequate O2 concentration, the second O2 molecule is chemisorbed. This significantly improves the ability of the crystal plane to store oxygen. However, the undoped planes adsorb H2O molecules and undergo hydroxylation under the synthesis and processing conditions. The ability to adsorb O2 molecules is poor. The doping of Co2+ increases the electrical conductivity of the crystal plane and the electrical sensitivity of adsorbed O2 molecules, which is beneficial to the further improvement of the catalytic activity of the system. Fourier transform infrared spectroscopy (FTIR), and electrochemical impedance spectroscopy (EIS) techniques were used to confirm these results. The results indicate that the adsorption capacity of O2 present on the TiO2 (001) crystal plane can be changed by Co2+ doping to improve the catalytic activity of the crystal plane.

APA, Harvard, Vancouver, ISO, and other styles

18

Ellenberger, Mark R., Steven C. Richtsmeier, and David A. Dixon. "Reactive scattering of van der Waals molecules." Molecular Physics 56, no. 2 (October 10, 1985): 271–95. http://dx.doi.org/10.1080/00268978500102311.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Kleyn, A. W. "NON-REACTIVE ORIENTATIONS OF MOLECULES AT SURFACES." Progress in Surface Science 54, no. 3-4 (March 1997): 407–20. http://dx.doi.org/10.1016/s0079-6816(97)00016-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Wolniewicz, L., Juergen Hinze, and Alexander Alijah. "Reactive collisions of atoms with diatomic molecules." Journal of Chemical Physics 99, no. 4 (August 15, 1993): 2695–707. http://dx.doi.org/10.1063/1.465231.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Vetrivel, R., C. Richard A. Catlow, and Elisabeth A. Colbourn. "Simulation studies of reactive molecules in zeolites." Journal of the Chemical Society, Faraday Transactions 2 85, no. 5 (1989): 497. http://dx.doi.org/10.1039/f29898500497.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Jamali, Vahid, Nariman Farsad, Robert Schober, and Andrea Goldsmith. "Diffusive Molecular Communications With Reactive Molecules: Channel Modeling and Signal Design." IEEE Transactions on Molecular, Biological and Multi-Scale Communications 4, no. 3 (September 2018): 171–88. http://dx.doi.org/10.1109/tmbmc.2019.2931338.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Kaufman, J., S. Ferrone, M. Flajnik, M. Kilb, H. Völk, and R. Parisot. "MHC-like molecules in some nonmammalian vertebrates can be detected by some cross-reactive monoclonal antibodies." Journal of Immunology 144, no. 6 (March 15, 1990): 2273–80. http://dx.doi.org/10.4049/jimmunol.144.6.2273.

Full text

Abstract:

Abstract mAb to human and mouse MHC molecules were tested for binding to blood or spleen cells of various nonmammalian vertebrates by immunofluorescence and flow cytometry. Those that bound were used to immunoprecipitate cross-reactive molecules from biosynthetically or cell surface-labeled spleen or blood cells. In addition, mAb to human MHC molecules were screened by Western blots. As expected from the results with xenoantisera, there were few mAb that cross-reacted, and many of these cross-reactions were not specific for MHC-like molecules. Less than 10% of the mAb tested bound to the cells of any particular species, with very few positive for more than one species. Of those mAb that bound cells, many failed to precipitate any radioactive bands, and most bands precipitated were not recognizable as MHC-like molecules. Five mAb reacted with Xenopus class II, one of which also immunoprecipitated axolotl class II. Another of these reacted with a candidate for class II in the lamprey, but this molecule had features unlike those expected for mammalian class II molecules. Four other mAb reacted with candidate molecules. in the trout and shark. None of the mouse alloantibodies immunoprecipitated nonmammalian vertebrate MHC-like molecules. In contrast to the results with most xenoantisera, the mAb cross-reacting with amphibian class II molecules recognized a number of different linear epitopes on the surface of the polymorphic non-Ig beta 1 domain of class II molecules. Few mAb recognized bands in Western blots of nonmammalian vertebrate cells and the candidate molecules from fish had features different from known mammalian MHC molecules.

APA, Harvard, Vancouver, ISO, and other styles

24

Gregory, Philip D., Jacob A. Blackmore, Frye Matthew D, Luke M. Fernley, Sarah L. Bromley, Jeremy M. Hutson, and Simon L. Cornish. "Molecule–molecule and atom–molecule collisions with ultracold RbCs molecules." New Journal of Physics 23, no. 12 (December 1, 2021): 125004. http://dx.doi.org/10.1088/1367-2630/ac3c63.

Full text

Abstract:

Abstract Understanding ultracold collisions involving molecules is of fundamental importance for current experiments, where inelastic collisions typically limit the lifetime of molecular ensembles in optical traps. Here we present a broad study of optically trapped ultracold RbCs molecules in collisions with one another, in reactive collisions with Rb atoms, and in nonreactive collisions with Cs atoms. For experiments with RbCs alone, we show that by modulating the intensity of the optical trap, such that the molecules spend 75% of each modulation cycle in the dark, we partially suppress collisional loss of the molecules. This is evidence for optical excitation of molecule pairs mediated via sticky collisions. We find that the suppression is less effective for molecules not prepared in the spin-stretched hyperfine ground state. This may be due either to longer lifetimes for complexes in the dark or to laser-free decay pathways. For atom–molecule mixtures, RbCs + Rb and RbCs + Cs, we demonstrate that the rate of collisional loss of molecules scales linearly with the density of atoms. This indicates that, in both cases, the loss of molecules is rate-limited by two-body atom–molecule processes. For both mixtures, we measure loss rates that are below the thermally averaged universal limit.

APA, Harvard, Vancouver, ISO, and other styles

25

He, Bing, Bingke Li, and Hongwei Zhou. "Theoretical Study on Pyramidal C7N6–H3R3 Molecules." Australian Journal of Chemistry 72, no. 7 (2019): 501. http://dx.doi.org/10.1071/ch19015.

Full text

Abstract:

The pyramidal molecule C7N6H6 and its nine symmetric tri-substituted derivatives C7N6–H3R3 (R=OH, F, CN, N3, NH2, NO2, N=NH, N2H3, and C≡CH) were investigated computationally using the GAUSSIAN 09 program package. Natural bond orbital and atoms in molecules analyses, as well as valence bond theory were applied to investigate the bonding properties. In comparison to their well known analogues C6N7–R3, i.e. generic heptazines, it is found that these 10 molecules are all reactive. Further studies on the topological structures and ionization energy values indicate that the reactive site of the molecules is located at the carbon atom of the core frame. Even though C7N6–H3R3 are neutral molecules, the structures and properties of some are consistent with those of a carbanion, and indeed, they act like carbanions, or so-called carbanionoids. These carbanionoids may have an extensive impact in organic chemistry and organometallic chemistry.

APA, Harvard, Vancouver, ISO, and other styles

26

Matsui, K., H. Watanabe, and T. K. Shimizu. "Stability and formation process of hydrogen-bonded organic porous thin films: A molecular dynamics study." AIP Advances 12, no. 10 (October 1, 2022): 105109. http://dx.doi.org/10.1063/5.0106036.

Full text

Abstract:

Molecular dynamics simulation using the reactive force field was performed to investigate the stability and formation mechanisms of organic porous thin films made of 1,3,5-tris(4-carboxyphenyl) benzene (BTB) molecules fabricated at the air/water interface. A single-layer honeycomb structure is found to be unstable, whereas thicker films are stable, which is consistent with experimental findings. The slight corrugation of the existing film produces local charge variation that attracts isolated molecules via the Coulomb interaction. When the isolated molecule approaches the film, a hydrogen bond is formed, and then the molecule adjusts the adsorption configuration by itself to maximize both horizontal and vertical intermolecular interactions. The key to the initial hydrogen bond formation is suggested to be the density of the molecules provided in the system as well as the spontaneous alignment of the BTB molecules to the solution/water interface. Our study showed that the BTB film is stable, and the molecules are self-assembled without external forces in the quasi-two-dimensional system. These results suggest that the dominant factor for the film formation at the air/water interface is interactions among BTB molecules and confinement to the two-dimensional space.

APA, Harvard, Vancouver, ISO, and other styles

27

Konieczny, Krzysztof, Arkadiusz Ciesielski, Julia Bąkowicz, Tomasz Galica, and Ilona Turowska-Tyrk. "Structural Transformations in Crystals Induced by Radiation and Pressure. Part 7. Molecular and Crystal Geometries as Factors Deciding about Photochemical Reactivity under Ambient and High Pressures." Crystals 8, no. 7 (July 20, 2018): 299. http://dx.doi.org/10.3390/cryst8070299.

Full text

Abstract:

We studied the photochemical reactivity of salts of 4-(2,4,6-triisopropylbenzoyl)benzoic acid with propane-1,2-diamine (1), methanamine (2), cyclohexanamine (3), and morpholine (4), for compounds (1), (3), and (4) at 0.1 MPa and for compounds (1) and (2) at 1.3 GPa and 1.0 GPa, respectively. The changes in the values of the unit cell parameters after UV irradiation and the values of the intramolecular geometrical parameters indicated the possibility of the occurrence of the Norrish–Yang reaction in the case of all the compounds. The analysis of the intramolecular geometry and free spaces revealed which o-isopropyl group takes part in the reaction. For (1), the same o-isopropyl group should be reactive at ambient and high pressures. In the case of (2), high pressure caused the phase transition from the space group I2/a with one molecule in the asymmetric unit cell to the space group P1¯ with two asymmetric molecules. The analysis of voids indicated that the Norrish–Yang reaction is less probable for one of the two molecules. For the other molecule, the intramolecular geometrical parameters showed that except for the Norrish–Yang reaction, the concurrent reaction leading to the formation of a five-membered ring can also proceed. In (3), both o-isopropyl groups are able to react; however, the bigger volume of a void near 2-isopropyl may be the factor determining the reactivity. For (4), only one o-isopropyl should be reactive.

APA, Harvard, Vancouver, ISO, and other styles

28

Shirazi, Mahdi, and Simon D. Elliott. "Cooperation between adsorbates accounts for the activation of atomic layer deposition reactions." Nanoscale 7, no. 14 (2015): 6311–18. http://dx.doi.org/10.1039/c5nr00900f.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Kolluru, Gopi K., Xinggui Shen, and Christopher G. Kevil. "Reactive Sulfur Species." Arteriosclerosis, Thrombosis, and Vascular Biology 40, no. 4 (April 2020): 874–84. http://dx.doi.org/10.1161/atvbaha.120.314084.

Full text

Abstract:

Hydrogen sulfide has emerged as an important gaseous signaling molecule and a regulator of critical biological processes. However, the physiological significance of hydrogen sulfide metabolites such as persulfides, polysulfides, and other reactive sulfur species (RSS) has only recently been appreciated. Emerging evidence suggests that these RSS molecules may have similar or divergent regulatory roles compared with hydrogen sulfide in various biological activities. However, the chemical nature of persulfides and polysulfides is complex and remains poorly understood within cardiovascular and other pathophysiological conditions. Recent reports suggest that RSS can be produced endogenously, with different forms having unique chemical properties and biological implications involving diverse cellular responses such as protein biosynthesis, cell-cell barrier functions, and mitochondrial bioenergetics. Enzymes of the transsulfuration pathway, CBS (cystathionine beta-synthase) and CSE (cystathionine gamma-lyase), may also produce RSS metabolites besides hydrogen sulfide. Moreover, CARSs (cysteinyl-tRNA synthetase) are also able to generate protein persulfides via cysteine persulfide (CysSSH) incorporation into nascently formed polypeptides suggesting a new biologically relevant amino acid. This brief review discusses the biochemical nature and potential roles of RSS, associated oxidative stress redox signaling, and future research opportunities in cardiovascular disease.

APA, Harvard, Vancouver, ISO, and other styles

30

Galaction, Anca-Irina, Maria Camarut, and Dan Cascaval. "Separation of p-aminobenzoic acid by reactive extraction: 1: Mechanism and influencing factors." Chemical Industry and Chemical Engineering Quarterly 14, no. 3 (2008): 159–65. http://dx.doi.org/10.2298/ciceq0803159g.

Full text

Abstract:

The comparative study on the reactive extraction of p-aminobenzoic acid with Amberlite LA-2 and D2EHPA in two solvents with different polarity (n-heptane and dichloromethane) indicated that the extractant type and solvent polarity control the extraction mechanism. Thus, the reactive extraction with Amberlite LA-2 occurs by means of the interfacial formation of an aminic adduct with three extractant molecules in low-polar solvent, or of an salt with one extractant molecule in higher polar solvent. Similarly, the extraction with D2EHPA is based on the formation of an acidic adduct with two extractant molecules in n-heptane, or of a salt with one extractant molecule in dichloromethane. The most efficient extraction has been reached for the combination Amberlite LA-2-dichloromethane.

APA, Harvard, Vancouver, ISO, and other styles

31

Napolitano, Gaetana, Gianluca Fasciolo, and Paola Venditti. "Mitochondrial Management of Reactive Oxygen Species." Antioxidants 10, no. 11 (November 17, 2021): 1824. http://dx.doi.org/10.3390/antiox10111824.

Full text

Abstract:

Mitochondria in aerobic eukaryotic cells are both the site of energy production and the formation of harmful species, such as radicals and other reactive oxygen species, known as ROS. They contain an efficient antioxidant system, including low-molecular-mass molecules and enzymes that specialize in removing various types of ROS or repairing the oxidative damage of biological molecules. Under normal conditions, ROS production is low, and mitochondria, which are their primary target, are slightly damaged in a similar way to other cellular compartments, since the ROS released by the mitochondria into the cytosol are negligible. As the mitochondrial generation of ROS increases, they can deactivate components of the respiratory chain and enzymes of the Krebs cycle, and mitochondria release a high amount of ROS that damage cellular structures. More recently, the feature of the mitochondrial antioxidant system, which does not specifically deal with intramitochondrial ROS, was discovered. Indeed, the mitochondrial antioxidant system detoxifies exogenous ROS species at the expense of reducing the equivalents generated in mitochondria. Thus, mitochondria are also a sink of ROS. These observations highlight the importance of the mitochondrial antioxidant system, which should be considered in our understanding of ROS-regulated processes. These processes include cell signaling and the progression of metabolic and neurodegenerative disease.

APA, Harvard, Vancouver, ISO, and other styles

32

Davis, Daly, and Y. Sajeev. "Low-energy-electron induced permanently reactive CO2 molecules." Phys. Chem. Chem. Phys. 16, no. 33 (2014): 17408–11. http://dx.doi.org/10.1039/c4cp02701a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Cong, Yang, Yu Zhai, Xin Chen, and Hui Li. "The Accuracy of Semi-Empirical Quantum Chemistry Methods on Soot Formation Simulation." International Journal of Molecular Sciences 23, no. 21 (November 2, 2022): 13371. http://dx.doi.org/10.3390/ijms232113371.

Full text

Abstract:

Soot molecules are hazardous compounds threatening human health. Computational chemistry provides efficient tools for studying them. However, accurate quantum chemistry calculation is costly for the simulation of large-size soot molecules and high-throughput calculations. Semi-empirical (SE) quantum chemistry methods are optional choices for balancing computational costs. In this work, we validated the performances of several widely used SE methods in the description of soot formation. Our benchmark study focuses on, but is not limited to, the validation of the performances of SE methods on reactive and non-reactive MD trajectory calculations. We also examined the accuracy of SE methods of predicting soot precursor structures and energy profiles along intrinsic reaction coordinate(s) (IRC). Finally, we discussed the spin density predicted by SE methods. The SE methods validated include AM1, PM6, PM7, GFN2-xTB, DFTB2, with or without spin-polarization, and DFTB3. We found that the shape of MD trajectory profiles, the relative energy, and molecular structures predicted by SE methods are qualitatively correct. We suggest that SE methods can be used in massive reaction soot formation event sampling and primary reaction mechanism generation. Yet, they cannot be used to provide quantitatively accurate data, such as thermodynamic and reaction kinetics ones.

APA, Harvard, Vancouver, ISO, and other styles

34

McDuffie, M., N. Roehm, J. W. Kappler, and P. Marrack. "Involvement of major histocompatibility complex products in tolerance induction in the thymus." Journal of Immunology 141, no. 6 (September 15, 1988): 1840–47. http://dx.doi.org/10.4049/jimmunol.141.6.1840.

Full text

Abstract:

Abstract KJ23a+ T cell clones, which bear the determinant encoded by the V beta 17a T cell receptor gene segment, frequently recognize IE molecules of various murine H-2 haplotypes. In the presence of IE molecules, thymic maturation of KJ23a+ clones is infrequent. We investigated the basis of this phenomenon by blocking expression of IE molecules with monoclonal anti-IE antibodies in organ cultures of fetal thymus and in neonates from the C57BR/cdJ strain (H-2k, V beta 17a homozygous). Our data support the contention that this process results from deletion of clones with anti-IE reactivity, as functional blocking of the IE molecule results in maturation of IE-reactive clones and increased numbers of KJ23a+ mature cells. In addition, we noted that blocking of functional IE expression in this haplotype permitted development of both CD4+/KJ23a+ and CD8+/KJ23a+ T cells. The CD4+ clones isolated from anti-IE-treated animals were frequently reactive against IEk; we could demonstrate no alloreactivity against B cell or B lymphoma stimulators in the CD4- clones. We conclude that clonal deletion events during thymic development may be initiated by T cell precursor interactions with MHC molecules against which the mature clones display no measurable reactivity. Specifically, clones destined to be MHC Class I-reactive may be deleted during development by interactions with MHC Class II molecules.

APA, Harvard, Vancouver, ISO, and other styles

35

del Castillo, Roxana, Roberto Salcedo, Ana Martínez, Estrella Ramos, and Luis Sansores. "Electronic Peculiarities of a Self-Assembled M12L24 Nanoball (M = Pd+2, Cr, or Mo)." Molecules 24, no. 4 (February 21, 2019): 771. http://dx.doi.org/10.3390/molecules24040771.

Full text

Abstract:

We use molecular mechanics and DFT calculations to analyze the particular electronic behavior of a giant nanoball. This nanoball is a self-assembled M12L24 nanoball; with M equal to Pd+2; Cr; and Mo. These systems present an extraordinarily large cavity; similar to biological giant hollow structures. Consequently, it is possible to use these nanoballs to trap smaller species that may also become activated. Molecular orbitals, molecular hardness, and Molecular Electrostatic Potential enable us to define their potential chemical properties. Their hardness conveys that the Mo system is less reactive than the Cr system. Eigenvalues indicate that electron transfer from the system with Cr to other molecules is more favorable than from the system with Mo. Molecular Electrostatic Potential can be either positive or negative. This means that good electron donor molecules have a high possibility of reacting with positive regions of the nanoball. Each of these nanoballs can trap 12 molecules, such as CO. The nanoball that we are studying has large pores and presents electronic properties that make it an apposite target of study.

APA, Harvard, Vancouver, ISO, and other styles

36

Kurtz, M. E., D. Martin-Morgan, and R. J. Graff. "Recognition of the beta-2 microglobulin-B molecule by a CTL clone." Journal of Immunology 138, no. 1 (January 1, 1987): 87–90. http://dx.doi.org/10.4049/jimmunol.138.1.87.

Full text

Abstract:

Abstract In this report we offer evidence that the beta-2 microglobulin-B (beta 2M-B) molecule is recognized by a cytotoxic T lymphocyte (CTL). Production of GA5, a CTL clone reactive against a membrane antigen with the same strain distribution pattern as beta 2M-B, is described. This clone lysed syngeneic target cells in which native beta 2M-A molecules had been exchanged with beta 2M-B molecules by incubating the cells in serum from beta 2M-B-positive mouse strains. Conversely, the CTL clone GA5 failed to lyse its specific target when beta 2M-B molecules had been exchanged with beta 2M-A molecules by incubating the cells in serum from beta 2M-A-positive, beta 2M-B-negative mouse strains. Strain combinations were chosen so as to limit reactivity to beta 2M and to preclude reactivity to H-3 antigens, thus indicating CTL clone GA5 to be reacting specifically with beta 2M-B.

APA, Harvard, Vancouver, ISO, and other styles

37

Lei, Ning Ning, De Li Gong, Xiao Rui Ling, and Yi Dong Shi. "Researches on Microwave Dyeing Cotton Fabrics." Advanced Materials Research 627 (December 2012): 343–47. http://dx.doi.org/10.4028/www.scientific.net/amr.627.343.

Full text

Abstract:

This experiment compared four different dyeing cotton fabrics processes with the reactive dye. It was found that under microwave irradiation dyeing, the dye-uptake and fixed percentage of the reactive dye were improved significantly and the salt and the alkali dosage in the dyeing bath were greatly reduced. Analysis found by XRD that microwave irradiation did not significantly change the internal structure of the cotton fibers and only slightly increased the orientation degree of them, so the tensile strength of the fabric was not significantly altered. Therefore, the main function of microwave in dyeing process was that its alternating electric field made the dye and the fiber molecule polarization, to increase the thermal motion of the molecules and the interaction between the polar molecules, thereby improving the dyeing rate and the fixing rate of the reactive dye.

APA, Harvard, Vancouver, ISO, and other styles

38

Firth, N. C., N. W. Keane, D. J. Smith, and R. Grice. "Reactive Scattering of Oxygen Atoms With Bromine Molecules." Laser Chemistry 9, no. 4-6 (January 1, 1988): 265–76. http://dx.doi.org/10.1155/lc.9.265.

Full text

Abstract:

Reactive scattering of O atoms with Br2 molecules has been studied at an initial translational energy E~35 kJ mol−1 using cross-correlation time-of-flight analysis with resolution improved over previous measurements. The centre-of-mass differential cross section peaks in the forward and backward directions with a higher product translational energy for backward Scattering. The angular distribution traced at the peak of the product velocity distribution peaks more sharply in the forward than the backward direction but the angular distribution of product flux shows a distribution which is more nearly symmetrical about θ = 90°. The observed scattering is attributed to a triplet OBrBr complex intermediate with a lifetime which is shorter than the period of overall rotation of the axis of the heavy BrBr diatomic but which is long compared with the period of vibrational and rotational motion of the light O atom.

APA, Harvard, Vancouver, ISO, and other styles

39

Firth, N. C., N. W. Keane, D. J. Smith, and R. Grice. "Reactive Scattering of Oxygen Atoms With Iodine Molecules." Laser Chemistry 9, no. 4-6 (January 1, 1988): 277–88. http://dx.doi.org/10.1155/lc.9.277.

Full text

Abstract:

Reactive scattering of O atoms with I2 molecules has been studied at an initial translational energy E~43 kJ mol−1 using cross-correlation time-of-flight analysis with resolution improved overprevious measurements. The broad centre-of-mass differential cross section favours the backward hemisphere with a product translational energy distribution lying above the distribution observed at lower initial translational energy but below the microcannonical RRHO distribution. However, a minor component with very low product translational energy favours the forward hemisphere. The observed scattering is attributed to a strongly bent OII triplet complex intermediate with a lifetime shorter than the period of overall rotation of the axis of the heavy II diatomic but long compared with the period of vibrational and rotational motion of the light O atom.

APA, Harvard, Vancouver, ISO, and other styles

40

Wurzer, A. J., S. Lochbrunner, and E. Riedle. "Highly localized vibronic wavepackets in large reactive molecules." Applied Physics B 71, no. 3 (September 2000): 405–9. http://dx.doi.org/10.1007/s003400000401.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Wang, Yuzhong, and Gregory H. Robinson. "Carbene Stabilization of Highly Reactive Main-Group Molecules." Inorganic Chemistry 50, no. 24 (December 19, 2011): 12326–37. http://dx.doi.org/10.1021/ic200675u.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Andreoli, Sharon P. "Reactive oxygen molecules, oxidant injury and renal disease." Pediatric Nephrology 5, no. 6 (1991): 733–42. http://dx.doi.org/10.1007/bf00857888.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Navada, M., I. Gupta, and V. Dhawan. "Reactive molecules and microorganisms and copper intrauterine devices." International Journal of Gynecology & Obstetrics 89, no. 3 (May 24, 2005): 282–83. http://dx.doi.org/10.1016/j.ijgo.2003.02.001.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Richmond, Thomas G. "Organometallic Transformations Demonstrate That Fluorocarbons Are Reactive Molecules." Angewandte Chemie 39, no. 18 (September 15, 2000): 3241–44. http://dx.doi.org/10.1002/1521-3773(20000915)39:18<3241::aid-anie3241>3.0.co;2-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Preston III, James F., and Ronald S. Hencin. "Carbodiimide-mediated conjugation of hippuric acid to concanavalin A: retention of ligand binding and hemagglutinating activities." Biochemistry and Cell Biology 64, no. 12 (December 1, 1986): 1366–71. http://dx.doi.org/10.1139/o86-179.

Full text

Abstract:

Conditions for conjugating small molecules with reactive carboxyl groups to concanavalin A (ConA), with retention of biological activity of the lectin, are described. Hippuric acid was conjugated to reactive amino groups on ConA with N-ethyl-N′-(dimethylaminopropyl)carbodiimide under conditions in which neither inter- nor intra-molecular cross-linking was detectable. These same conditions provided for the loading of variable amounts of hippurate as a function of reaction time; conjugates were synthesized with 9.6 mol hippurate∙mol ConA−1. Conjugation in the presence of 0.1 M phosphate provided a condition for limiting the extent of coupling; only amide linkages were formed. These conjugates retained both the ability to bind ligands and the hemagglutination titer of the native lectin.

APA, Harvard, Vancouver, ISO, and other styles

46

Abbaz, Tahar, Amel Bendjeddou, and Didier Villemin. "Structural and quantum chemical studies on aryl sulfonyl piperazine derivatives." Journal of Drug Delivery and Therapeutics 9, no. 1-s (February 15, 2019): 88–97. http://dx.doi.org/10.22270/jddt.v9i1-s.2264.

Full text

Abstract:

The optimized molecular structure and electronic features of aryl sulfonyl piperazine derivatives 1-4 have been investigated theoretically using Gaussian 09 software package and DFT/B3LYP method with 6-31G (d,p) basis set. The reactivity of the title molecules was investigated and both the positive and negative centers of the molecules were identiﬁed using molecular electrostatic potential (MEP) analysis which the results illustrate that the regions reveal the negative electrostatic potential are localized in sulfamide function while the regions presenting the positive potential are localized in the hydrogen atoms. The energies of the frontier molecular orbitals and LUMO-HOMO energy gap are measured to explain the electronic transitions. Global reactivity parameters of the aryl sulfonyl piperazine derivatives molecules were predicted to find that the more reactive and softest compound is the compound 3. Mulliken’s net charges have been calculated and results show that 3N is the more negative and 33S is the more positive charge, which Indicates extensive charge delocalization in the entire molecule. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization (π→π transitions) has been analyzed using NBO analysis. Fist hyperpolarizability is calculated in order to ﬁnd its importance in non-linear optics and the results show that the studied molecules have not the NLO applications. Keywords: sulfamide; density functional theory; computational chemistry; electronic structure; quantum chemical calculations.

APA, Harvard, Vancouver, ISO, and other styles

47

Guélin, Michel. "Radio and Millimetre Observations of Less Complex Molecules." Symposium - International Astronomical Union 120 (1987): 171–81. http://dx.doi.org/10.1017/s0074180900153987.

Full text

Abstract:

Progress in laboratory and astronomical instrumentation has renewed the already large interest for simple astrophysical molecules. On the laboratory side, one of the most notable advances has been the spectroscopic observation of an increasing number of small reactive molecular species. On the astronomical side, the access to submillimetre wavelengths and the completion of millimetric interferometers and large single-dish telescopes, have allowed the detection of many new molecular species and open the way for detailed studies of the distribution of molecules in interstellar and circumstellar clouds.

APA, Harvard, Vancouver, ISO, and other styles

48

Naik, Edwina, and Vishva M. Dixit. "Mitochondrial reactive oxygen species drive proinflammatory cytokine production." Journal of Experimental Medicine 208, no. 3 (February 28, 2011): 417–20. http://dx.doi.org/10.1084/jem.20110367.

Full text

Abstract:

High levels of reactive oxygen species (ROS) are observed in chronic human diseases such as neurodegeneration, Crohn’s disease, and cancer. In addition to the presence of oxidative stress, these diseases are also characterized by deregulated inflammatory responses, including but not limited to proinflammatory cytokine production. New work exploring the mechanisms linking ROS and inflammation find that ROS derived from mitochondria act as signal-transducing molecules that provoke the up-regulation of inflammatory cytokine subsets via distinct molecular pathways.

APA, Harvard, Vancouver, ISO, and other styles

49

Nemova, E. A., G. G. Dultseva, N. A. Nikolaev, and O. P. Cherkasova. "Effect of terahertz radiation on intermolecular interactions of albumin under aerobic and anaerobic conditions." Journal of Physics: Conference Series 2067, no. 1 (November 1, 2021): 012015. http://dx.doi.org/10.1088/1742-6596/2067/1/012015.

Full text

Abstract:

Abstract The effect of THz radiation on coupling between albumin molecules under aerobic and anaerobic conditions is assessed through an EPR-quantified procedure. Rearrangements induced by terahertz radiation are found to affect the hydrogen bonding network causing an increase in the rate of bimolecular interactions. Molecular mechanism of the observed effect is considered involving the interactions between the functional groups of albumin molecules. Irradiation causes conformational changes in albumin molecules, which involves changes in the steric states of molecules. These rearrangements hinder or simplify the adsorption of specific agents on the reactive sites of albumin molecules.

APA, Harvard, Vancouver, ISO, and other styles

50

Veeresham, A., M. Sandeep, T. Jagadeshwar Reddy, A. Suresh Pal, K. Srinivas, and S. Prabhakar. "Gas chromatography/mass spectrometry analysis of reaction products of sulfur mustards with phenol." European Journal of Mass Spectrometry 26, no. 3 (November 7, 2019): 213–24. http://dx.doi.org/10.1177/1469066719886424.

Full text

Abstract:

Screening of chemicals related to chemical weapons convention including their all possible degradation and reaction products in environmental samples is important in the organization for prohibition of chemical weapons verification process. Sulfur mustards, commonly known as blistering agents, are included in schedule 1 chemicals of chemical weapons convention. Because of the presence of chlorine atoms in sulfur mustards, they are highly reactive and prone to react with other organic molecules such as phenols to produce corresponding reaction products. Thus, it is important to screen for not only the sulfur mustards but also their reaction products for verification process. The sulfur mustards and their degradation products have been routinely analyzed by gas chromatography/mass spectrometry method, however, the methods are yet to establish for the reaction products. In this study, the reaction products of the sulfur mustards with phenol (compounds 1–7) were studied by gas chromatography/mass spectrometry under electron ionization and chemical ionization conditions. The EI spectra of 1–7 displayed molecular ion and characteristic fragments that provided structure information. Mostly the fragment ions were due to homolytic cleavages involving C–O, C–S, and C–C cleavages. The methane or isobutane CI spectra showed M+., [M + H]+, and [M − H]+ ions including reagent specific adduct ions. The CI spectra also showed other adduct ions formed by association of analyte molecule with its most abundant fragment ion. The gas chromatography/retention index values were also calculated, which support unambiguous identification of targeted molecules in suspected environmental samples. The method was demonstrated for detection of the targeted molecules spiked in soil samples.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Reactive molecules'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles