Search results for "crossover"
showing 10 items of 658 documents
Anomalous pressure dependence of the Lamb-Mössbauerf-factor in the spin crossover system [Fe(2-pic-ND2)3]Cl2·EtOD
1987
The pressure dependence of the Lamb-Mossbauer factor of the spin crossover compound [Fe(2-pic-ND2)3]Cl2·EtOD(2-pic-ND2=2-picolylamine, deuterated at the−NH2 group) has been measured at pressures up to 1500 bar and at three temperatures (115.7, 146.7, 185.6 K) around the transition temperatureT t=135 K. The temperature dependence of the unit cell volume has been determined by X-ray diffraction. In the transition region (T=146.7 K), the pressure dependence of thef-factor shows an anomalous increase as compared to the dependence below and above the transition. The behaviour off(p, T), its anomaly and absolute value, can be consistently explained within a theoretical model which treats the comp…
X-ray study of the light-induced metastable state of a spin-crossover compound
2000
Iron(II) complexes exhibiting thermal spin crossover may be converted from the1A1low-spin (LS) state to the5T2high-spin (HS) state by irradiation with green light (light-induced excited spin-state trapping, LIESST). The lifetime of the metastable LIESST state may be sufficiently long for X-ray diffraction study. The lattice parameters of a single crystal of [Fe(ptz)6](BF4)2(ptz = propyltetrazole) were measured between 300 and 10 K, while the crystal changed from the HS to the LS state near 135 K. Using the green light (514 nm) of an argon-ion laser, the crystal was quantitatively converted to the metastable LIESST state at 10 K; its lattice parameters were measured up to 50 K, at which poin…
The LIESST state of [Fe(pic)3]Cl2.EtOH – the superstructure under continuous irradiation
2005
The superstructure recently discovered in [Fe(pic)3]Cl2.EtOH at temperatures inside the step region of the high-spin–low-spin transition curve sheds new light on the anomalous transition behaviour in spin crossover compounds. The structure of the metastable LIESST state of [Fe(pic)3]Cl2.EtOH at 10 K has been measured. The decay has been followed by X-ray diffraction using a CCD camera in order to detect reflections of the superstructure building up during the decay. No signal above the noise of the CCD camera was observed, so that even diffuse scattering could not be detected. This finding is in agreement with correlation lengths of pair correlations of molecules in the HS and LS states bei…
A genetic system based on simulated crossover of sequences of two-bit genes
2006
AbstractWe introduce a genetic model based on simulated crossover of fixed sequences of two-bit genes. Results are(1)a lower bound on population size is exhibited such that a transition takes the stochastic finite population genetic system near the next state of the deterministic infinite population genetic system (provided both begin in the same state);(2)states and dynamics of the deterministic infinite population genetic system are derived for arbitrary (finite) fitness functions (expressed in terms of multivariate polynomials);(3)in the case of quadratic fitness defined by weight matrices with m nonnull entries it is shown that each state transition can be implemented in time O(m+l), wh…
Ecological momentary assessment for chronic pain in fibromyalgia using a smartphone: A randomized crossover study
2013
Background Daily diaries are a useful way of measuring fluctuations in pain-related symptoms. However, traditional diaries do not assure the gathering of data in real time, not solving the problem of retrospective assessment. Ecological momentary assessment (EMA) by means of electronic diaries helps to improve repeated assessment. However, it is important to test its feasibility in specific populations in order to reach a wider number of people who could benefit from these procedures. Methods The present study compares the compliance and acceptability of an electronic diary running on a smartphone using a crossover design for a sample with a specific pain condition, fibromyalgia and low fam…
Revisiting the Profitability of Market Timing with Moving Averages
2017
In a recent empirical study by Glabadanidis (“Market Timing with Moving Averages” (2015), International Review of Finance 15(13):387–425), the author reports striking evidence of extraordinarily good performance of the moving average trading strategy. In this paper, we demonstrate that this “too good to be true” reported performance of the moving average strategy is due to simulating trading with look-ahead bias. We perform simulations without look-ahead bias and report the true performance of the moving average strategy. We find that, at best, the performance of the moving average strategy is only marginally better than that of the corresponding buy-and-hold strategy. In statistical terms,…
The Limits of Ego Depletion
2019
Abstract. Evidence on the existence of the ego depletion phenomena as well as the size of the effects and potential moderators and mediators are ambiguous. Building on a crossover design that enables superior statistical power within a single study, we investigated the robustness of the ego depletion effect between and within subjects and moderating and mediating influences of the ego depletion manipulation checks. Our results, based on a sample of 187 participants, demonstrated that (a) the between- and within-subject ego depletion effects only had negligible effect sizes and that there was (b) large interindividual variability that (c) could not be explained by differences in ego depleti…
First Example of Coexistence of Thermal Spin Transition and Liquid-Crystal Properties.
2001
The rodlike FeIII complex of an N-alkyloxysalicylidenyl-N'-ethyl-N-ethylenediamine ligand, shown as a computer model in the picture, is the first compound in which spin-crossover (SC) and liquid-crystalline (LC) properties coexist. This synergy should allow the magnetic and optical properties of SC compounds to be combined with the sensitivity of the LC state to electromagnetic fields.
Revisiting the Profitability of Market Timing with Moving Averages
2016
In a recent empirical study by Glabadanidis ("Market Timing With Moving Averages" (2015), International Review of Finance, Volume 15, Number 13, Pages 387-425; the paper is also available on the SSRN and has been downloaded more than 7,500 times) the author reports striking evidence of extraordinary good performance of the moving average trading strategy. In this paper we demonstrate that "too good to be true" reported performance of the moving average strategy is due to simulating the trading with look-ahead bias. We perform the simulations without look-ahead bias and report the true performance of the moving average strategy. We find that at best the performance of the moving average stra…
Spin Crossover Systems
2015
Abstract This account constitutes a basic introduction to spin crossover phenomena that is mostly encountered for iron(II) coordination complexes. After briefly describing the occurrence of spin transition in liquid and solid states, the effects of pressure and light irradiation are discussed. Applications and recent trends of this expanding field are also presented.