Advances in in situ molecular systems for phytoplankton research and monitoring

Positron annihilation lifetime measurements have been performed on three molecular systems: propylene carbonate, salol and m-toluidine at the temperature range from 20 K up to 300 K. The time dependences of the orthopositronium lifetime and intensity have been observed at the temperature range between a solid state and the liquid state. These changes can be explained as transitions from the amorphous phase to one or two crystalline phases. The crystallization process from cooled liquid was observed in all three cases at different temperatures on the time scale up to 60 hours.

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ON THE PERTURBATION METHODS FOR SOME NONLINEAR QUANTUM CHEMISTRY MODELS

Mathematical Models and Methods in Applied Sciences ◽

10.1142/s0218202598000044 ◽

1998 ◽

Vol 08 (01) ◽

pp. 55-94 ◽

Cited By ~ 6

Author(s):

ERIC CANCÈS ◽

CLAUDE LE BRIS

Keyword(s):

Electric Field ◽

Quantum Chemistry ◽

Perturbation Methods ◽

Existence Of Solutions ◽

Mathematical Foundation ◽

Molecular Systems ◽

Hartree Fock ◽

Nonlinear Quantum ◽

Solvated Molecules

The purpose of this article is to (a) give a sound mathematical foundation to perturbation methods for some nonlinear quantum chemistry models. This contributes to the understanding of computations on molecular systems in situ, such as solvated molecules or molecules subjected to a uniform external electric field and (b) prove in the latter setting a result of non-existence of solutions to the Thomas–Fermi–Von Weizsäcker and to the Hartree–Fock equations, which is the nonlinear counterpart of a result by Avron and Herbst.2

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Spectroelectrochemical Properties and Catalytic Activity in Cyclohexane Oxidation of the Hybrid Zr/Hf-Phthalocyaninate-Capped Nickel(II) and Iron(II) tris-Pyridineoximates and Their Precursors

Molecules ◽

10.3390/molecules26020336 ◽

2021 ◽

Vol 26 (2) ◽

pp. 336

Author(s):

Yan Z. Voloshin ◽

Semyon V. Dudkin ◽

Svetlana A. Belova ◽

Daniel Gherca ◽

Dumitru Samohvalov ◽

...

Keyword(s):

Density Functional ◽

Redox Activity ◽

Oxidation Reactions ◽

Paramagnetic Resonance ◽

Molecular Systems ◽

Near Ir ◽

Voltammetric Studies ◽

Cyclic Voltammetric Studies ◽

Electron Paramagnetic

The in situ spectroelectrochemical cyclic voltammetric studies of the antimony-monocapped nickel(II) and iron(II) tris-pyridineoximates with a labile triethylantimony cross-linking group and Zr(IV)/Hf(IV) phthalocyaninate complexes were performed in order to understand the nature of the redox events in the molecules of heterodinuclear zirconium(IV) and hafnium(IV) phthalocyaninate-capped derivatives. Electronic structures of their 1e-oxidized and 1e-electron-reduced forms were experimentally studied by electron paramagnetic resonance (EPR) spectroscopy and UV−vis−near-IR spectroelectrochemical experiments and supported by density functional theory (DFT) calculations. The investigated hybrid molecular systems that combine a transition metal (pseudo)clathrochelate and a Zr/Hf-phthalocyaninate moiety exhibit quite rich redox activity both in the cathodic and in the anodic region. These binuclear compounds and their precursors were tested as potential catalysts in oxidation reactions of cyclohexane and the results are discussed.

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Nitrosonium nitrate (NO+NO3 −) structure solution using in situ single-crystal X-ray diffraction in a diamond anvil cell

IUCrJ ◽

10.1107/s2052252521000075 ◽

2021 ◽

Vol 8 (2) ◽

pp. 208-214

Author(s):

Dominique Laniel ◽

Bjoern Winkler ◽

Egor Koemets ◽

Timofey Fedotenko ◽

Stella Chariton ◽

...

Keyword(s):

Single Crystal ◽

Density Functional ◽

High Pressures ◽

Density Functional Theory Calculations ◽

X Ray Diffraction ◽

X Ray ◽

Molecular Systems ◽

Structure Solution ◽

Diamond Anvil

At high pressures, autoionization – along with polymerization and metallization – is one of the responses of simple molecular systems to a rise in electron density. Nitrosonium nitrate (NO+NO3 −), known for this property, has attracted a large interest in recent decades and was reported to be synthesized at high pressure and high temperature from a variety of nitrogen–oxygen precursors, such as N2O4, N2O and N2–O2 mixtures. However, its structure has not been determined unambiguously. Here, we present the first structure solution and refinement for nitrosonium nitrate on the basis of single-crystal X-ray diffraction at 7.0 and 37.0 GPa. The structure model (P21/m space group) contains the triple-bonded NO+ cation and the NO3 − sp 2-trigonal planar anion. Remarkably, crystal-chemical considerations and accompanying density-functional-theory calculations show that the oxygen atom of the NO+ unit is positively charged – a rare occurrence when in the presence of a less-electronegative element.

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Tipping solutions: emerging 3D nano-fabrication/ -imaging technologies

Nanophotonics ◽

10.1515/nanoph-2017-0008 ◽

2017 ◽

Vol 6 (5) ◽

pp. 923-941 ◽

Cited By ~ 20

Author(s):

Gediminas Seniutinas ◽

Armandas Balčytis ◽

Ignas Reklaitis ◽

Feng Chen ◽

Jeffrey Davis ◽

...

Keyword(s):

Focused Ion Beam ◽

Imaging Technique ◽

Ion Beam ◽

Three Dimensional ◽

Molecular Systems ◽

Force Microscopy ◽

Nano Fabrication ◽

Atomic Force ◽

Scanning Electron

AbstractThe evolution of optical microscopy from an imaging technique into a tool for materials modification and fabrication is now being repeated with other characterization techniques, including scanning electron microscopy (SEM), focused ion beam (FIB) milling/imaging, and atomic force microscopy (AFM). Fabrication and in situ imaging of materials undergoing a three-dimensional (3D) nano-structuring within a 1−100 nm resolution window is required for future manufacturing of devices. This level of precision is critically in enabling the cross-over between different device platforms (e.g. from electronics to micro-/nano-fluidics and/or photonics) within future devices that will be interfacing with biological and molecular systems in a 3D fashion. Prospective trends in electron, ion, and nano-tip based fabrication techniques are presented.

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Abstract LB-A03: Molecular systems-guided imaging of multicellular in situ adaptation to targeted therapy in BRAF-mutant cancer

10.1158/1535-7163.targ-19-lb-a03 ◽

2019 ◽

Author(s):

Stephanie Wang ◽

Ralph Weissleder ◽

Douglas Lauffenburger ◽

Miles Miller

Keyword(s):

Targeted Therapy ◽

Molecular Systems ◽

Braf Mutant

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Rendez vous with Saturn's rings

International Astronomical Union Colloquium ◽

10.1017/s0252921100101885 ◽

1984 ◽

Vol 75 ◽

pp. 743-759 ◽

Cited By ~ 2

Author(s):

Kerry T. Nock

Keyword(s):

Solar Energy ◽

Electric Propulsion ◽

Power Source ◽

Propulsion System ◽

Low Thrust ◽

Ring Plane ◽

The Earth ◽

Total Impulse ◽

Saturn's Rings

ABSTRACTA mission to rendezvous with the rings of Saturn is studied with regard to science rationale and instrumentation and engineering feasibility and design. Future detailedin situexploration of the rings of Saturn will require spacecraft systems with enormous propulsive capability. NASA is currently studying the critical technologies for just such a system, called Nuclear Electric Propulsion (NEP). Electric propulsion is the only technology which can effectively provide the required total impulse for this demanding mission. Furthermore, the power source must be nuclear because the solar energy reaching Saturn is only 1% of that at the Earth. An important aspect of this mission is the ability of the low thrust propulsion system to continuously boost the spacecraft above the ring plane as it spirals in toward Saturn, thus enabling scientific measurements of ring particles from only a few kilometers.

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