Chemical composition is leading among the numerous factors that determine the spin transition properties of coordination compounds. Classic dicyanometallic bridges {M(CN)
2
}
−
are commonly used to ...build Hofmann-like spin-crossover frameworks, but some extended bridges are also synthetically available. In this paper, we describe a successful synthesis of two very similar spin-crossover frameworks that differ in the cyanometallic bridges involved, namely Fe(etpz)
2
{Ag(CN)
2
}
2
(
1
) and {Fe(etpz)
2
Ag
2
(CN)
3
Ag(CN)
2
} (
2
) (where etpz = 2-ethylpyrazine). Magnetic and Mössbauer studies demonstrated the occurrence of abrupt one-step high-spin (HS) ↔ low-spin (LS) transitions for both complexes. The spin transition temperatures are
T
1/2
↓ = 233 K and
T
1/2
↑ = 243 K for
1
and
T
1/2
↓ = 188 K and
T
1/2
↑ = 191 K for
2
with thermal hysteresis loops of 10 K for
1
and 3 K for
2
. The bridging mononuclear Ag(CN)
2
−
units and Fe
II
cations assemble to form infinite 2D layers in the structure of
1
. Interestingly, compound
2
forms 2D layers of Fe
II
cations bridged by both binuclear Ag
2
(CN)
3
−
and mononuclear Ag(CN)
2
−
units. The structures of
1
and
2
comprise different types of intermolecular interactions including Ag Ag and Ag N
etpz
, which induce the creation of supramolecular 3D frameworks. The synergy between metallophilic interactions and the spin transition is also confirmed by the variation of Ag Ag distances during spin crossover. The characterization of such analogues allowed us to analyze in detail the effect of the cyanometallic bridge on the structure of new frameworks and on the bistability in Hofmann-like complexes.
Chemical composition is leading among the numerous factors that determine the spin transition properties of coordination compounds.
Eye-tracking research in infants and older children has gained a lot of momentum over the last decades. Although eye-tracking research in these participant groups has become easier with the advance ...of the remote eye-tracker, this often comes at the cost of poorer data quality than in research with well-trained adults (Hessels, Andersson, Hooge, Nyström, & Kemner
Infancy
,
20
, 601–633,
2015
; Wass, Forssman, & Leppänen
Infancy
,
19
, 427–460,
2014
). Current fixation detection algorithms are not built for data from infants and young children. As a result, some researchers have even turned to hand correction of fixation detections (Saez de Urabain, Johnson, & Smith
Behavior Research Methods
,
47
, 53–72,
2015
). Here we introduce a fixation detection algorithm—identification by two-means clustering (I2MC)—built specifically for data across a wide range of noise levels and when periods of data loss may occur. We evaluated the I2MC algorithm against seven state-of-the-art event detection algorithms, and report that the I2MC algorithm’s output is the most robust to high noise and data loss levels. The algorithm is automatic, works offline, and is suitable for eye-tracking data recorded with remote or tower-mounted eye-trackers using static stimuli. In addition to application of the I2MC algorithm in eye-tracking research with infants, school children, and certain patient groups, the I2MC algorithm also may be useful when the noise and data loss levels are markedly different between trials, participants, or time points (e.g., longitudinal research).
This paper explores a Bayesian update strategy applying the experts' subjective viewpoints concerning the wind turbines' preventive maintenance. The approach is general enough to be employed in other ...than wind turbine maintenance applications. Although extant literature has examined the implementation of optimal adaptive Bayesian update strategies relating to the preventive maintenance time, they have not expanded the findings to the subjective views of wind farm managers or technicians. Against this backdrop, subjective opinions have been successfully deployed herein for Bayesian updates in the meantime the experts explore key distribution parameters without any prior expertise of statistics by merely putting forth opinions as disbelief, belief, or ambiguity. The choices, along with their concomitant effect on statistical parameters, including the minimized time of maintenance and new approach of costs, are presented before the wind farm manager and technician directly in the form of quantitative data, whereas their inputs are considered as opinion. Notably, such an approach adjuncts the quantitative data from turbine supervisory control and data acquisition (SCADA). As an integral component of turbine failures, the preventive maintenance pitch control device has been explored in this paper, which demonstrates the viability of this approach. A reliability networks Bayesian update strategy that develops the subjective opinions of variable and random costs are formulated and systematically investigated for preventive maintenance while several expert opinion has been implemented by the author in an earlier preliminary study. The reliability network is implemented for components where the SCADA does not provide clear data where the technician (expert) has opinion.
ABSTRACT
Radiocarbon (
14
C) dating has, since its inception, become an integral part of disciplines such as geology and archaeology, underpinning many key findings made by researchers in the past ...seven decades. As
14
C dating develops, the need arises to revisit older findings and legacy data which may well contain laboratory errors or post-analysis misinterpretations. In this paper we examine one such finding from Sweden, namely the 1958
14
C dating of the great Jordfallet (“the Earthfall”) landslide, which was published in the very first volume of
Radiocarbon
in 1959. We further trace how the results of this
14
C dating were misunderstood in a time prior to modern radiocarbon calibration, and the impact which this mistake has had throughout academic publications, state reports and local heritage literature through the course of over sixty years. Because of this flawed interpretation the credible date of 1249 AD given to the landslide by historical sources has been overlooked. Instead, a series of dates from the mid-12th and early 13th centuries have been attributed to the landslide event based on erroneous radiocarbon analysis, a mistake which has substantial implications for the understanding of both regional and international history in medieval Scandinavia.
Bacteria and other potential pathogens are cleared rapidly from the body fluids of invertebrates by the immediate response of the innate immune system. Proteolytic cascades, following their ...initiation by pattern recognition proteins, control several such reactions, notably coagulation, melanisation, activation of the Toll receptor and complement-like reactions. However, there is considerable variation among invertebrates and these cascades, although widespread, are not present in all phyla. In recent years, significant progress has been made in identifying and characterizing these cascades in insects. Notably, recent work has identified several connections and shared principles among the different pathways, suggesting that cross-talk between them may be common.
•Inexpensive and simple synthesis route for flexible PAN-NH2 nanofibers.•Obtained high loading capacity of Cr(VI) in comparison to other adsorbents.•High desorption efficiency allowing the reuse of ...PAN-NH2 nanofibers.•The flexibility of PAN-NH2 nanofibers allows use in a continuous operation mode.
Polyacrylonitrile (PAN) nanofibers functionalized with amine groups (PAN-NH2) were prepared using a simple one-step reaction route. The PAN-NH2 nanofibers were investigated for the removal of chromium(VI) from aqueous solutions. The adsorption and the kinetic characteristics were evaluated in batch process. The adsorption process showed pH dependence and the maximum Cr(VI) adsorption occurred at pH=2. The Langmuir adsorption model described well the experimental adsorption data and estimated a maximum loading capacity of 156mg/g, which is a markedly high value compared to other adsorbents reported. The kinetics studies indicated that the equilibrium was attained after 90min and the experimental data followed a pseudo-second order model suggesting a chemisorption process as the rate limiting step. X-ray Photoelectron Spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR) revealed that the adsorption of Cr(VI) species on PAN-NH2 was facilitated through both electrostatic attraction and surface complexation. High desorption efficiency (>90%) of Cr(VI) was achieved using diluted base solutions that may allow the reuse of PAN-NH2 nanofibers.
We report the synthesis of injectable in situ forming hybrid hydrogel material and investigate its ability to support the mineralization process under mild conditions. To achieve this, we have ...prepared a hyaluronic acid (HA) derivative that is dually functionalized with cross-linkable hydrazide groups and bisphosphonate ligands (HA-hy-BP). The hybrid hydrogel can be formed by simple mixing of two solutions: the solution of HA-hy-BP and the Ca2+ ions containing solution of aldehyde-derivatized HA (HA-al). We found that the conjugation of BP, a P–C–P analogue of pyrophosphate, to the hydrogel matrix promotes an efficient and fast mineralization of the matrix. The mineralization is facilitated by the strong interaction between BP residues and Ca2+ ions that serve as nanometer-sized nucleation points for further calcium phosphate deposition within the HA hydrogel. Compared with previously reported hydrogel template-driven mineralization techniques, the present approach is maximally adapted for clinical settings since the formation of the hybrid takes place during quick mixing of the sterilized solutions. Moreover, the hybrid hydrogel is formed from in vivo degradable components of the extracellular matrix and therefore can be remodeled in vivo through concerted HA degradation and calcium phosphate mineralization.
The variability of wind power will be an increasing challenge for the power system as wind penetration grows and thus needs to be studied. In this paper a model for generation of hourly aggregated ...wind power time series is described and evaluated. The model is based on MERRA reanalysis data and information on wind energy converters in Sweden. Installed capacity during the studied period (2007–2012) increased from around 600 to over 3500 MW. When comparing with data from the Swedish TSO, the mean absolute error in hourly energy was 2.9% and RMS error was 3.8%. The model was able to adequately capture step changes and also yielded a nicely corresponding distribution of hourly energy. Two key factors explaining the good results were the use of a globally optimised power curve smoothing parameter and the correction of seasonal and diurnal bias.
Because of bottlenecks in the Swedish transmission system it is relevant to model certain areas separately. For the two southern areas the MAE were 3.7 and 4.2%. The northern area was harder to model and had a MAE of 6.5%. This might be explained by a low installed capacity, more complex terrain and icing losses not captured in the model.
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