Building on our report that collision-induced dissociation (CID) can be used to create the highly reactive U-alkylidyne species O=U≡CH
, our goal was to determine whether the species could be as an ...intermediate for synthesis of OUS
by reaction with carbon disulfide (CS
).
Cationic uranyl-propiolate precursor ions were generated by electrospray ionization, and multiple-stage CID in a linear trap instrument was used to prepare O=U≡CH
. Neutral CS
was admitted into the trap through a modified He inlet and precision leak valves.
The O=U≡CH
ion reacts with CS
to generate OUS
. CID of OUS
causes elimination of the axial sulfide ligand to generate OU
. Using isotopically labeled reagent, we found that OUS
reacts with O
to create UO
.
O=U≡CH
proves to be a useful reagent ion for synthesis of OUS
, a species that to date has only been created by gas-phase reactions of U
and U
. Dissociation of OUS
to create OU
, but not US
, and the efficient conversion of the species into UO
, is consistent with the relative differences in U-O and U-S bond energies.
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2.
The g factor of highly charged ions Harman, Z; Sikora, B; Yerokhin, V A ...
Journal of physics. Conference series,
11/2018, Volume:
1138, Issue:
1
Journal Article
Peer reviewed
Open access
Recent years have witnessed a remarkable improvement in the theoretical description of bound-electron g factors, paralleled with a quantum jump in the experimental accuracy in the investigation of ...these quantities. In the present article we give a brief summary of the latest developments, with emphasis on the influence of quantum electrodynamic and nuclear effects on the g factor of few-electron highly charged ions, and on the possible determination of fundamental constants.
The importance of the heavy ions and dust grains for the chemistry and aerosol formation in Titan's ionosphere has been well established in the recent years of the Cassini mission. In this study we ...combine independent in situ plasma (Radio Plasma and Wave Science Langmuir Probe (RPWS/LP)) and particle (Cassini Plasma Science Electron Spectrometer, Cassini Plasma Science Ion Beam Spectrometer, and Ion and Neutral Mass Spectrometer) measurements of Titan's ionosphere for selected flybys (T16, T29, T40, and T56) to produce altitude profiles of mean ion masses including heavy ions and develop a Titan‐specific method for detailed analysis of the RPWS/LP measurements (applicable to all flybys) to further constrain ion charge densities and produce the first empirical estimate of the average charge of negative ions and/or dust grains. Our results reveal the presence of an ion‐ion (dusty) plasma below ~1100 km altitude, with charge densities exceeding the primary ionization peak densities by a factor ≥2 in the terminator and nightside ionosphere (ne/ni ≤ 0.1). We suggest that ion‐ion (dusty) plasma may also be present in the dayside ionosphere below 900 km (ne/ni < 0.5 at 1000 km altitude). The average charge of the dust grains (≥1000 amu) is estimated to be between −2.5 and −1.5 elementary charges, increasing toward lower altitudes.
Key Points
Detection of electron‐depleted dusty ion‐ion plasma in lower ionosphere with enhanced densities
First empirical estimate of the negative ion and dust grain charge
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Data-independent acquisition modes isolate and concurrently fragment populations of different precursors by cycling through segments of a predefined precursor m/z range. Although these selection ...windows collectively cover the entire m/z range, overall, only a few per cent of all incoming ions are isolated for mass analysis. Here, we make use of the correlation of molecular weight and ion mobility in a trapped ion mobility device (timsTOF Pro) to devise a scan mode that samples up to 100% of the peptide precursor ion current in m/z and mobility windows. We extend an established targeted data extraction workflow by inclusion of the ion mobility dimension for both signal extraction and scoring and thereby increase the specificity for precursor identification. Data acquired from whole proteome digests and mixed organism samples demonstrate deep proteome coverage and a high degree of reproducibility as well as quantitative accuracy, even from 10 ng sample amounts.
We show that an ion‐ion cross‐field streaming instability between cold newborn cometary ions and heated heavy ions that were picked up upstream is likely a contributing source of observed lower ...hybrid (LH) waves in the inner coma of comet 67P/Churyumov‐Gerasimenko. Electric field oscillations in the LH frequency range are common here, and have previously been attributed mainly to the lower‐hybrid drift instability, driven by gradients associated with observed local density fluctuations. However, the observed wave activity is not confined to such gradients, nor is it always strongest there. Thus, other instabilities are likely needed as well to explain the observed wave activity. Several previous works have shown the existence of multiple populations of cometary ions in the inner coma of 67P, distinguished by differences in mass, energy and/or flow direction. We here examine two selected time intervals in October and November 2015, with substantial wave activity in the LH frequency range, where we identify two distinct cometary ion populations: a bulk population of locally produced, predominantly radially outflowing ions, and a more tenuous population picked up further upstream and accelerated back toward the comet by the solar wind electric field. These two populations exhibit strong relative drifts (∼20 km/s, or about five times the pickup ion thermal velocity), and we perform an electrostatic dispersion analysis showing that conditions should be favorable for LH wave generation through the ion‐ion cross‐field instability.
Key Points
Pick‐up ions and locally produced cometary ions co‐occur in the inner coma, with strong relative streaming motion
An ion‐ion cross‐field instability can develop as a result of the relative streaming motion
This instability can be responsible for generating at least some of the lower hybrid waves observed at the comet
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A facile and convenient approach for the synthesis of multi-functionalized calix4arenes through multi-component reactions is described. A series of five new calix4arene-hexaamide derivatives were ...synthesized, and their structures were elucidated by means of spectroscopic data. The value of this method lies in its operational simplicity, mild reaction conditions, structural diversity of products, and good yields. Furthermore, fluorescence studies demonstrated considerable binding affinity of these new calix4arenes toward beta-lactoglobulin protein.
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Recently, rechargeable zinc‐ion batteries in mild acidic electrolytes have attracted considerable research interest as a result of their high sustainability, safety, and low cost. However, the use of ...conventional Zn‐ion storage materials is hindered by insufficient specific capacity, sluggish reaction kinetics, or poor cycle life. Here, these limitations are addressed by pre‐intercalating alkali ions and water crystals into layered δ‐MnO2 (birnessite) to prepare K0.27MnO2·0.54H2O (KMO) and Na0.55Mn2O4·1.5H2O with ultrathin nanosheet morphology via a rapid molten salt method. In these materials, alkali ions and water crystals act as pillars to stabilize the layered structures, which can enable rapid diffusion of cations in the KMO structure, resulting in high power capability (90 mAh g−1 at 10 C) and good cycling stability. Furthermore, electrochemical quartz crystal microbalance measurements shed light on the charge storage mechanism of KMO in an aqueous Zn‐ion battery which, combined together with in‐operando X‐ray diffraction techniques, suggests that the charge storage process is dominated by the (de)intercalation of H3O+ with further dissolution–precipitation of Zn4(OH)6(SO4)·5H2O solid product on the KMO surface during cycling.
A molten salt‐prepared K0.27MnO2·0.54H2O cathode achieves a high capacity of 288 mAh g−1 at C/3 and high‐power capability (88 mAh g−1 at 10 C) in an aqueous Zn‐ion battery configuration. The combination of in situ XRD and electrochemical quartz crystal microbalance reveal a charge storage process dominated by (de)intercalation of (hydrated) protons with further dissolution–precipitation of Zn4(OH)6(SO4)·5H2O.
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EtNH3+(NG3−) is generally considered as the first reported room temperature ionic liquid which was synthesized and characterized by Paul Walden in 1914. But the present investigation finds that ...EtNH3+(NG3−), a similar kind of ionic salt which is liquid at room temperature, was synthesized by Sir P C Rây three years earlier (in 1911) to Walden. Unfortunately, the latter work had not been paid any attention for more than a century because of unknown reasons. As per literature review, henceforth, Sir P C Rây and his coauthor (J N Rakshit) of that very particular synthesis of the ionic compound which was liquid at room temperature should be regarded as the discoverer of room temperature ionic liquid.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
J. Sep. Sci. 2017, 40, 834-841 DOI: 10.1002/jssc.201601122 The cover picture shows the discovery of the saponin difference between Xueshuantong Injection (XShTI) and Xuesaitong Injection (XSaTI) and ...the possible factor related to the chemical difference by ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry based metabolomics. Wuzhou XShTI displays remarkable differentiation from the other products, with richer protopanaxatriol-type noto-R1, Rg1, Re and protopanaxadiol-type Rb1, but less Rd and other low-polarity protopanaxadiol-type ginsenosides. Diverse preparation techniques, rather than the use of different parts of Panax notoginseng, may be the major factor leading to the observed chemical difference. The results are beneficial to the quality control of these Notoginseng total saponins products.
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