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91.
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93.
Jaquay Cook Ashleigh Hicks Tyan Frazier David M. Kimari Theodore A. Budzichowski Jeanette A. Krause Bauer Santosh K. Mandal 《Journal of chemical crystallography》2003,33(5-6):481-489
The monodentate dithioformato complexes, fac-(CO)3(dppe)MnSC(S)H (1), fac- (CO)3(dppe)ReSC(S)H (2), fac-(CO)3(dppp)ReSC(S)H (3), and fac-(CO)3 (dppb)ReSC(S)H (4), where dppe is 1,2-bis(diphenylphosphino)ethane, dppp is 1,3-bis(diphenylphosphino)propane, and dppb is 1,4-bis(diphenylphosphino)butane, were synthesized from the treatment of the corresponding hydrides, fac-(CO)3 (P-P)MSC(S)H with CS2. Compounds 1–4 crystallize in the monoclinic crystal system: for 1, space group = P21/c, a = 15.3139(3) Å, b = 9.7297(4) Å, c = 19.0991(6) Å, = 105.928(1), V = 2736.5 Å3, Z = 4; for 2, space group = P21/c, a = 15.6395(8) Å, b = 9.8182(5) Å, c = 19.4153(11) Å, = 106.741(1), V = 2854.9(3) Å3, Z = 4; for 3, space group = P21/n, a = 11.3570(10) Å, b = 19.465(2) Å, c = 15.5702(14) Å, = 104.776(2), V = 3328.3(5) Å3, Z = 4; and for 4, space group = C2/c, a = 32.078(2) Å, b = 10.4741(6) Å, c = 19.0608(9) Å, = 94.315(2), V = 6386.1(6) Å3, Z = 8. 相似文献
94.
Parametric decay of the upper hybrid mode is observed between the electron cyclotron frequency and its first two harmonics. The decay products are identified as electron Bernstein and ion acoustic mode. The diagnostic results confirm the relevant dispersion relations. 相似文献
95.
Prof. Dr. Jean Christophe Tremblay Ambre Blanc Dr. Pascal Krause Sucharita Giri Prof. Gopal Dixit 《Chemphyschem》2023,24(2):e202200463
The present work focuses on probing ultrafast charge migration after symmetry-breaking excitation using ultrashort laser pulses. LiCN is chosen as prototypical system because it can be oriented in the laboratory frame and it possesses optically-accessible charge transfer states at low energies. The charge migration is simulated within the hybrid time-dependent density functional theory/configuration interaction framework. Time-resolved electronic current densities and simulated time-resolved x-ray diffraction signals are used to unravel the mechanism of charge migration. Our simulations demonstrate that specific choices of laser polarization lead to a control over the symmetry of the induced charge migration. Moreover, time-resolved x-ray diffraction signals are shown to encode transient symmetry reduction at intermediate times. 相似文献
96.
Christian Huber Christian Krause Tobias Werner Otto S. Wolfbeis 《Mikrochimica acta》2003,142(4):245-253
This article describes the preparation and performance of an optical sensor for continuous measurement of chloride at extracellular (serum) levels (20–200mM). The sensor is based on dynamic quenching of the fluorescence of lucigenin which was photo-immobilized on a hydrogel. Quenching occurs via a collisional mechanism, and the decrease in fluorescence intensity on exposure to 100mM chloride typically is –60%. It allows the determination of chloride in the 1 to 200mM concentration range, with a precision of ±3mM at 120mM. Bromide, iodide and salicylate act as interferents, while the effect of pH and oxygen is negligibly small. The sensor displays strong fluorescence intensity, excellent reproducibility, long-term stability, response times in the order of 2–5min, and is used in a commercial serum and blood chloride analyzer.Received January 21, 2003; accepted April 6, 2003
Published online July 28, 2003 相似文献
97.
Michael J. Goldcamp Jeanette A. Krause Bauer Michael J. Baldwin 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):e602-e603
Tris[2‐(benzoylamino)ethyl]amine [alternatively, N,N′,N′′‐(nitrilotriethyl)tribenzamide], C27H30N4O3, adopts a folded structure, forming a symmetrical cavity with an average depth of 7.3 Å and width ranging from 4.1–4.4 Å. The folded structure is a result of one intramolecular N—H?O hydrogen bond. A linear chain motif along the c axis best describes the extended intermolecular N—H?O hydrogen bonding. 相似文献
98.
Anthony L. Spek Johannes Canisius Hans Preut Norbert Krause 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1065-1066
The title compound, di‐μ‐chloro‐bis{[(2,3,4‐η)‐ethyl 6,6‐dimethyl‐5‐oxohept‐2‐enoato]palladium(II)}, [Pd2Cl2(C11H17O3)2], is a binuclear chloro‐bridged palladium allyl complex that was obtained serendipitously From the reaction of 6,6‐dimethyl‐2‐hepten‐4‐ynoate with Na2PdCl4 in water‐containing alcohol. The allyl group is substituted with an ester and a tert‐butylcarboxy group. The dimeric molecules link via C—H?O contacts into a two‐dimensional network parallel to the bc plane. 相似文献
99.
Beatriz F. dos Santos Caroline F. Pereira Mikaela P. Pinz Aline R. de Oliveira George Brand Ramesh Katla Ethel A. Wilhelm Cristiane Luchese Nelson L.C. Domingues 《应用有机金属化学》2020,34(7):e5650
Functionalization of 2,1,3-benzothiadiazole (BTD) with thiols at C-5 position remains low explored. Moreover, the arylthiol-substitutions at this position are also unexplored and can not be found by a SN2 or SN1 reaction. In this sense, herein we present a new palladium-catalyzed methodology for a wide variety of unpublished 5-arylsulfanyl-benzo-2,1,3-thiadiazole derivatives synthesis with moderate to high yields using a low catalytic loading of Pd(L-Pro)2 as low-coast, and efficient catalyst in low reaction time. Besides, we concluded that the pKa of thiol species has an important role in this catalysis, mainly in the CMD like catalytic cyclo process, which strongly interferes in the reaction yields. Furthermore, arylsulfanyl-benzo-2,1,3-thiadiazoles derivatives have been assessed (in vitro) as potential acetylcholinesterase inhibitors. 相似文献
100.
Cristiane P. de Macedo Charles A. B. Negrão Luiz G. M. de Macedo José R. Zamian Geraldo N. da Rocha Filho Carlos E. F. da Costa 《Journal of Thermal Analysis and Calorimetry》2014,115(1):31-36
The Al-MCM-41 molecular sieve with Si/Al = 20 molar ratio was synthesized at room temperature and characterized by X-ray diffractometry, surface area, thermogravimetry, and infrared spectroscopy. The kinetic study was conducted by Vyazovkin and Ozawa method, in order to verify the activation energy during the Hofmann degradation between 130 and 370 °C, in which most of surfactant removal occurs. The results suggest that the activation energy for template removal is close to 80 kJ mol?1 lower in Al-MCM-41 synthesized at room temperature, when compared to results obtained for mesopores Al-MCM-41 and MCM-41 synthesized by hydrothermal method. This lower activation energy may be understood as consequence of textural properties, such as higher pore size. 相似文献