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31.
Zusammenfassung In Fortsetzung unserer Untersuchungen über den Mechanismus der Bleikammerreaktion wird die Aufteilung der Umsetzung von schwefliger mit salpetriger Säure zwischen die Richtungen nach NO und N2O insbesondere in ihrer Abhängigkeit von der Schwefelsäure-(H.-)Konzentration experimentell verfolgt. Die Ergebnisse werden im Sinne des in unserer ersten Mitteilung enthaltenen Versuches einer Deutung des hier obwaltenden Mechanismus diskutiert.Auch bei vorliegender Untersuchung hatten wir uns der materiellen Unterstützung seitens derÖsterreichischen Dynamit Nobel Akt.-Ges., Wien, zu erfreuen, wofür wir dem Unternehmen und seinen leitenden Herren GeneraldirektorErwin Philipp und Direktor Ing. BelaFreund auch an dieser Stelle bestens danken. 相似文献
32.
E. Abel 《Monatshefte für Chemie / Chemical Monthly》1949,80(3):379-388
Zusammenfassung Es wird die Annahme zur Diskussion gestellt, daß salpetrige Säure auch im Sinne von {ie388-1} zu reagieren vermag. Ein allgemeines Reaktionsschema für die Wirkungsweise von salpetriger Säure als Oxydans wird entwickelt. Einige Oxydationsreaktionen der salpetrigen Säure werden in diesem Sinne diskutiert. Im besonderen wird versucht, diesem Reaktionsschema den Mechanismus der dem Bleikammerverfahren zugrunde liegenden Oxydation von schwefliger Säure durch salpetrige Säure an Hand seinerzeitiger experimenteller Befunde einzuordnen. Der viel diskutierte Oxydationsvorgang bei Bildung von Schwefelsäure im Bleikammerverfahren innerhalb der flüssigen Phase scheint in seinen wesentlichen Hauptzügen aufgeklärt zu sein. 相似文献
33.
Tepavcevic S Zachary AM Wroble AT Choi Y Hanley L 《The journal of physical chemistry. A》2006,110(4):1618-1624
Conducting polymer films are grown by either mass-selected or non-mass-selected, hyperthermal thiophene ions coincident on a surface with a thermal beam of organic monomers of either alpha-terthiophene (3T) or p-terphenyl (3P) neutrals. Previous experiments verified polymerization of both 3T and 3P by 200 eV C(4)H(4)S(+) during surface polymerization by ion-assisted deposition (SPIAD). A wide variety of structures are observed by scanning electron microscopy to form in the SPIAD polythiophene and polyphenyl films. These structures include microscale islands, lamellar structures, fractal-like growth patterns, and nanoscale crystallites. Some of the deposited films diffract X-rays while others show electron micrographs of crystallites. The variation of these patterns with deposition conditions clearly indicate that ion-induced polymerization mediates film morphology through control of ion energy and ion/neutral ratio. Furthermore, these ion-assisted events mediate important thermal processes such as sublimation. 相似文献
34.
Synthesis of Inorganic Structural Isomers By Diffusion‐Constrained Self‐Assembly of Designed Precursors: A Novel Type of Isomerism 下载免费PDF全文
Marco Esters Matti B. Alemayehu Zachary Jones Dr. N. T. Nguyen Dr. Michael D. Anderson Corinna Grosse Prof. Saskia F. Fischer Prof. David C. Johnson 《Angewandte Chemie (International ed. in English)》2015,54(4):1130-1134
The structure of precursors is used to control the formation of six possible structural isomers that contain four structural units of PbSe and four structural units of NbSe2: [(PbSe)1.14]4[NbSe2]4, [(PbSe)1.14]3[NbSe2]3[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]3[NbSe2]2[(PbSe)1.14]1[NbSe2]2, [(PbSe)1.14]2[NbSe2]3[(PbSe)1.14]2[NbSe2]1, [(PbSe)1.14]2[NbSe2]2[(PbSe)1.14]1[NbSe2]1[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]2[NbSe2]1[(PbSe)1.14]1[NbSe2]2[(PbSe)1.14]1[NbSe2]1. The electrical properties of these compounds vary with the nanoarchitecture. For each pair of constituents, over 20 000 new compounds, each with a specific nanoarchitecture, are possible with the number of structural units equal to 10 or less. This provides opportunities to systematically correlate structure with properties and hence optimize performance. 相似文献
35.
Textile/Metal–Organic‐Framework Composites as Self‐Detoxifying Filters for Chemical‐Warfare Agents 下载免费PDF全文
Elena López‐Maya Dr. Carmen Montoro Dr. L. Marleny Rodríguez‐Albelo Dr. Salvador D. Aznar Cervantes Dr. A. Abel Lozano‐Pérez Prof. José Luis Cenís Dr. Elisa Barea Prof. Jorge A. R. Navarro 《Angewandte Chemie (International ed. in English)》2015,54(23):6790-6794
The current technology of air‐filtration materials for protection against highly toxic chemicals, that is, chemical‐warfare agents, is mainly based on the broad and effective adsorptive properties of hydrophobic activated carbons. However, adsorption does not prevent these materials from behaving as secondary emitters once they are contaminated. Thus, the development of efficient self‐cleaning filters is of high interest. Herein, we report how we can take advantage of the improved phosphotriesterase catalytic activity of lithium alkoxide doped zirconium(IV) metal–organic framework (MOF) materials to develop advanced self‐detoxifying adsorbents of chemical‐warfare agents containing hydrolysable P? F, P? O, and C? Cl bonds. Moreover, we also show that it is possible to integrate these materials onto textiles, thereby combining air‐permeation properties of the textiles with the self‐detoxifying properties of the MOF material. 相似文献
36.
Zachary D. Miller Ruth Dorel Prof. John Montgomery 《Angewandte Chemie (International ed. in English)》2015,54(31):9088-9091
Methods for the highly stereoselective and regiodivergent hydrosilylation of 1,3‐disubstituted allenes have been developed. The synthesis of E allylsilanes is accomplished with palladium NHC catalysts, and trisubstituted Z alkenylsilanes are accessed with nickel NHC catalysts. Unsymmetrically substituted allenes are well tolerated with nickel catalysis and afford Z alkenylsilanes. Evidence for a plausible mechanism was obtained through an isotopic double‐labeling crossover study. 相似文献
37.
38.
Averin A. D. Uglov A. N. Zubrienko G. A. Abel A. S. Buryak A. K. Beletskaya I. P. 《Russian Chemical Bulletin》2021,70(11):2164-2179
Russian Chemical Bulletin - The Pd-catalyzed tetraarylation of diamines and oxadiamines with 2,7-dibromonaphthalenes and 4,4′-dibromobiphenyl was studied. These reactions gave the... 相似文献
39.
Energized molecules are the essential actors in chemical transformations in solution. As the rearrangement of bonds requires a movement of nuclei, vibrational energy is often the driving force for a reaction. Vibrational energy can be redistributed within the "hot" molecule, or relaxation can occur when molecules interact. Both processes govern the rates, pathways, and quantum yields of chemical transformations in solution. Unfortunately, energy transfer and the breaking, formation, and rearrangement of bonds take place on ultrafast timescales. This Review highlights experimental approaches for the direct, ultrafast measurement of photoinduced femtochemistry and energy flow in solution. In the first part of this Review, we summarize recent experiments on intra- and intermolecular energy transfer. The second part discusses photoinduced decomposition of large organic peroxides, which are used as initiators in free radical polymerization. The mechanisms and timescales of their decarboxylation determine the initial steps of polymerization and the microstructure of the polymer product. 相似文献
40.
Katherine A. Gibney Iva Sovadinova Analette I. Lopez Michael Urban Zachary Ridgway Gregory A. Caputo Kenichi Kuroda 《Macromolecular bioscience》2012,12(9):1279-1289
We report the structure–activity relationship in the antimicrobial activity of linear and branched poly(ethylene imine)s (L‐ and B‐PEIs) with a range of molecular weights (MWs) (500–12 000). Both L‐ and B‐PEIs displayed enhanced activity against Staphylococcus aureus over Escherichia coli. Both B‐ and L‐PEIs did not cause any significant permeabilization of E. coli cytoplasmic membrane. L‐PEIs induced depolarization of S. aureus membrane although B‐PEIs did not. The low MW B‐PEIs caused little or no hemolysis while L‐PEIs are hemolytic. The low MW B‐PEIs are less cytotoxic to human HEp‐2 cells than other PEIs. However, they induced significant cell viability reduction after 24 h incubation. The results presented here highlight the interplay between polymer size and structure on activity.