In situ Ge–Ge bond formation under ambient conditions: synthesis, characterization and reactivity of organo-functionalized telluridogermanate complexes

2011 ◽  
Vol 47 (6) ◽  
pp. 1881-1883 ◽  
Author(s):  
Samuel Heimann ◽  
Małgorzata Hołyńska ◽  
Stefanie Dehnen
Keyword(s):  
Bond Formation ◽  
Ambient Conditions

Hypervalent iodine(iii) catalyzed oxidative C–N bond formation in water: synthesis of benzimidazole-fused heterocycles

RSC Advances ◽  
2014 ◽  
Vol 4 (49) ◽  
pp. 25600-25604 ◽  
Author(s):  
D. Nageswar Rao ◽  
Sk. Rasheed ◽  
Ram A. Vishwakarma ◽  
Parthasarathi Das
Keyword(s):  
Bond Formation ◽  
Hypervalent Iodine ◽  
Ambient Conditions ◽  
Fused Heterocycles

A diverse array of benzimidazole-fused heterocycles was synthesized by in situ generated hypervalent iodine(iii) catalyzed intramolecular oxidative C–N bond formation in water and under ambient conditions.

scholarly journals Diffusion-induced in situ growth of covalent organic frameworks for composite membranes

2019 ◽  
Vol 7 (45) ◽  
pp. 25802-25807 ◽  
Author(s):  
Priyanka Manchanda ◽  
Stefan Chisca ◽  
Lakshmeesha Upadhyaya ◽  
Valentina-Elena Musteata ◽  
Mark Carrington ◽  
...  
Keyword(s):  
Reaction Times ◽  
Composite Membranes ◽  
Thin Layers ◽  
In Situ Growth ◽  
Covalent Organic Frameworks ◽  
Polymeric Support ◽  
Ambient Conditions ◽  
Induction Method ◽  
Covalent Organic Framework

Thin layers of a covalent organic framework (COF) have been synthesized on a flexible polymeric support using a new diffusion-induction method under ambient conditions in reaction times as short as 3 hours.

ChemInform Abstract: C-C Bond Formation via C-H Bond Activation Using an in situ Generated Ruthenium Catalyst.

ChemInform ◽  
2009 ◽  
Vol 40 (44) ◽  
Author(s):  
Remi Martinez ◽  
Marc-Olivier Simon ◽  
Reynald Chevalier ◽  
Cyrielle Pautigny ◽  
Jean-Pierre Genet ◽  
...  
Keyword(s):  
Bond Activation ◽  
Bond Formation ◽  
Ruthenium Catalyst

In Situ Formation of Cationic π-Allylpalladium Precatalysts in Alcoholic Solvents: Application to C–N Bond Formation

ACS Catalysis ◽  
2021 ◽  
pp. 560-567
Author(s):  
Philippe Steinsoultz ◽  
Aurélien Bailly ◽  
Patrick Wagner ◽  
Estefania Oliva ◽  
Martine Schmitt ◽  
...  
Keyword(s):  
Bond Formation ◽  
In Situ Formation

Measurement of Cement in Situ Stresses and Mechanical Properties Without Cooling or Depressurization

2021 ◽  
Author(s):  
Meng Meng ◽  
Luke Frash ◽  
James Carey ◽  
Wenfeng Li ◽  
Nathan Welch ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Elastic Modulus ◽  
Poisson’S Ratio ◽  
Axial Stress ◽  
Triaxial Compression ◽  
In Situ Measurement ◽  
Poisson's Ratio ◽  
Ambient Conditions

Abstract Accurate characterization of oilwell cement mechanical properties is a prerequisite for maintaining long-term wellbore integrity. The drawback of the most widely used technique is unable to measure the mechanical property under in situ curing environment. We developed a high pressure and high temperature vessel that can hydrate cement under downhole conditions and directly measure its elastic modulus and Poisson's ratio at any interested time point without cooling or depressurization. The equipment has been validated by using water and a reasonable bulk modulus of 2.37 GPa was captured. Neat Class G cement was hydrated in this equipment for seven days under axial stress of 40 MPa, and an in situ measurement in the elastic range shows elastic modulus of 37.3 GPa and Poisson's ratio of 0.15. After that, the specimen was taken out from the vessel, and setted up in the triaxial compression platform. Under a similar confining pressure condition, elastic modulus was 23.6 GPa and Possion's ratio was 0.26. We also measured the properties of cement with the same batch of the slurry but cured under ambient conditions. The elastic modulus was 1.63 GPa, and Poisson's ratio was 0.085. Therefore, we found that the curing condition is significant to cement mechanical property, and the traditional cooling or depressurization method could provide mechanical properties that were quite different (50% difference) from the in situ measurement.

scholarly journals Characterization of interferences to in situ observations of <i>δ</i><sup>13</sup>CH<sub>4</sub> and C<sub>2</sub>H<sub>6</sub> when using a cavity ring-down spectrometer at industrial sites

2017 ◽  
Vol 10 (6) ◽  
pp. 2077-2091 ◽  
Author(s):  
Sabina Assan ◽  
Alexia Baudic ◽  
Ali Guemri ◽  
Philippe Ciais ◽  
Valerie Gros ◽  
...  
Keyword(s):  
Near Infrared ◽  
Field Tests ◽  
Isotopic Signature ◽  
Ambient Conditions ◽  
Industrial Sites ◽  
Source Determination ◽  
Infrared Spectral ◽  
The Subject

Abstract. Due to increased demand for an understanding of CH4 emissions from industrial sites, the subject of cross sensitivities caused by absorption from multiple gases on δ13CH4 and C2H6 measured in the near-infrared spectral domain using CRDS has become increasingly important. Extensive laboratory tests are presented here, which characterize these cross sensitivities and propose corrections for the biases they induce. We found methane isotopic measurements to be subject to interference from elevated C2H6 concentrations resulting in heavier δ13CH4 by +23.5 ‰ per ppm C2H6 ∕ ppm CH4. Measured C2H6 is subject to absorption interference from a number of other trace gases, predominantly H2O (with an average linear sensitivity of 0.9 ppm C2H6 per  % H2O in ambient conditions). Yet, this sensitivity was found to be discontinuous with a strong hysteresis effect and we suggest removing H2O from gas samples prior to analysis. The C2H6 calibration factor was calculated using a GC and measured as 0.5 (confirmed up to 5 ppm C2H6). Field tests at a natural gas compressor station demonstrated that the presence of C2H6 in gas emissions at an average level of 0.3 ppm shifted the isotopic signature by 2.5 ‰, whilst after calibration we find that the average C2H6 : CH4 ratio shifts by +0.06. These results indicate that, when using such a CRDS instrument in conditions of elevated C2H6 for CH4 source determination, it is imperative to account for the biases discussed within this study.

Chromic Polydiacetylene Single Crystals: Atomic Force Microscopy Studies

1995 ◽  
Vol 413 ◽  
Author(s):  
V. Shivshankar ◽  
C. Sung ◽  
J. Kumar ◽  
S. K. Tripathy ◽  
D. J. Sandman
Keyword(s):  
Atomic Force Microscopy ◽  
Surface Morphology ◽  
Single Crystals ◽  
Ambient Conditions ◽  
Free Standing ◽  
Force Microscopy ◽  
Sensor Performance ◽  
Atomic Force ◽  
Variable Surface

ABSTRACTWe have studied the surface morphology of free standing single crystals of thermochromic polydiacetylenes (PDAs), namely, ETCD and IPUDO (respectively, the ethyl and isopropyl urethanes of 5,7-dodecadiyn-1,12-diol), by Atomic Force Microscopy (AFM) under ambient conditions. Micron scale as well as molecularly resolved images were obtained. The micron scale images indicate a variable surface, and the molecularly resolved images show a well defined 2-D lattice that is interpreted in terms of molecular models and known crystallographic data. Thereby information about surface morphology, which is crucial to potential optical device or chromic sensor performance is available. We also report the observation of a “macroscopic shattering” of the IPUDO monomer crystal during in-situ UV polymerization studies.

A kinetic study of mechanochemical halogen bond formation by in situ31P solid-state NMR spectroscopy

2017 ◽  
Vol 53 (71) ◽  
pp. 9930-9933 ◽  
Author(s):  
Yijue Xu ◽  
Lysiane Champion ◽  
Bulat Gabidullin ◽  
David L. Bryce
Keyword(s):  
Activation Energy ◽  
Solid State ◽  
Nmr Spectroscopy ◽  
Kinetic Study ◽  
Solid State Nmr ◽  
Halogen Bond ◽  
Bond Formation ◽  
Nmr Studies ◽  
Solid State Nmr Spectroscopy

In situ 31P solid-state NMR studies of mechanochemical halogen bond formation provide insights into the cocrystallisation process and an estimate of the activation energy.

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