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排序方式： 共有513条查询结果，搜索用时 15 毫秒
61.
62.
Archiv der Mathematik - Let X be a smooth projective surface and $$L\in \mathrm {Pic}(X)$$ . We prove that if L is $$(2k-1)$$ -spanned, then the set $${\tilde{V}}_k(L)$$ of all nodal and... 相似文献
63.
64.
Air quality in Province of Trieste was studied in terms of PM10 trends. Observed correlations between PM10 and atmospheric pollutants produced by combustion are in evidence. Nitrogen oxides and PM10 are critical parameters for air quality in Province of Trieste. Wind speed has a diluting action higher than rain for all pollutants. 相似文献
65.
Eunyoung Hong;Davide Nodari;Francesco Furlan;Edoardo Angela;Julianna Panidi;Martyn A. McLachlan;Nicola Gasparini; 《Advanced Optical Materials》2024,12(13):2302712
Formamidinium lead iodide (FAPbI3) has gained considerable interest as a promising photoactive layer for optoelectronic devices due to its broad spectrum of light absorption and increased thermal stability when compared to its conventional methylammonium counterpart (MAPbI3). Recent developments in substituting formamidinium (FA) with smaller Cs cations have further accelerated its growth in the photovoltaic (PV) community by enhancing phase stability and power conversion efficiency (PCE). However, only a few studies are reported on perovskite photodetectors (PPDs). Here, the influence of Cs incorporation is investigated on PD performance in the CsXFA1-XPbI3 system (X = 0–0.25). Finding that the partial substitution of FA with Cs cations alleviates lattice strain by increasing crystallinity and inducing a well-ordered surface morphology with vertical crystallographic orientation, which suppresses non-radiative recombination mechanisms. Such improved physicochemical properties of the mixed-cation perovskite light absorbers can improve the PD performance by reducing the dark and noise current to values as low as 3.3 × 10−9 A cm−2 and 6.1 × 1011 A Hz−1/2, thereby enabling PPDs with a faster photoresponse and greater sensitivity, which holds great promise for future optoelectronics applications. 相似文献
66.
Edoardo Artioli Paolo Bisegna 《International Journal of Solids and Structures》2013,50(7-8):1154-1163
This paper presents a homogenization method for unidirectional periodic composite materials reinforced by circular fibres with functionally graded coating layers. The asymptotic homogenization method is adopted, and the relevant cell problem is addressed. Periodicity is enforced by resorting to the theory of Weierstrass elliptic functions. The equilibrium equation in the coating domain is solved in closed form by applying the theory of hypergeometric functions, for different choices of grading profiles. The effectiveness of the present analytical procedure is proved by convergence analysis and comparison with finite element solutions. The influence of microgeometry and grading parameters on the shear stress concentration at the coating/matrix interface is addressed, aimed at the composite optimization in regards to fatigue and debonding phenomena. 相似文献
67.
Michele Braccini Andrea Roli Edoardo Barbieri Stuart A. Kauffman 《Entropy (Basel, Switzerland)》2022,24(10)
Systems poised at a dynamical critical regime, between order and disorder, have been shown capable of exhibiting complex dynamics that balance robustness to external perturbations and rich repertoires of responses to inputs. This property has been exploited in artificial network classifiers, and preliminary results have also been attained in the context of robots controlled by Boolean networks. In this work, we investigate the role of dynamical criticality in robots undergoing online adaptation, i.e., robots that adapt some of their internal parameters to improve a performance metric over time during their activity. We study the behavior of robots controlled by random Boolean networks, which are either adapted in their coupling with robot sensors and actuators or in their structure or both. We observe that robots controlled by critical random Boolean networks have higher average and maximum performance than that of robots controlled by ordered and disordered nets. Notably, in general, adaptation by change of couplings produces robots with slightly higher performance than those adapted by changing their structure. Moreover, we observe that when adapted in their structure, ordered networks tend to move to the critical dynamical regime. These results provide further support to the conjecture that critical regimes favor adaptation and indicate the advantage of calibrating robot control systems at dynamical critical states. 相似文献
68.
Michele Lo Giudice Giuseppe Varone Cosimo Ieracitano Nadia Mammone Giovanbattista Gaspare Tripodi Edoardo Ferlazzo Sara Gasparini Umberto Aguglia Francesco Carlo Morabito 《Entropy (Basel, Switzerland)》2022,24(1)
The differential diagnosis of epileptic seizures (ES) and psychogenic non-epileptic seizures (PNES) may be difficult, due to the lack of distinctive clinical features. The interictal electroencephalographic (EEG) signal may also be normal in patients with ES. Innovative diagnostic tools that exploit non-linear EEG analysis and deep learning (DL) could provide important support to physicians for clinical diagnosis. In this work, 18 patients with new-onset ES (12 males, 6 females) and 18 patients with video-recorded PNES (2 males, 16 females) with normal interictal EEG at visual inspection were enrolled. None of them was taking psychotropic drugs. A convolutional neural network (CNN) scheme using DL classification was designed to classify the two categories of subjects (ES vs. PNES). The proposed architecture performs an EEG time-frequency transformation and a classification step with a CNN. The CNN was able to classify the EEG recordings of subjects with ES vs. subjects with PNES with 94.4% accuracy. CNN provided high performance in the assigned binary classification when compared to standard learning algorithms (multi-layer perceptron, support vector machine, linear discriminant analysis and quadratic discriminant analysis). In order to interpret how the CNN achieved this performance, information theoretical analysis was carried out. Specifically, the permutation entropy (PE) of the feature maps was evaluated and compared in the two classes. The achieved results, although preliminary, encourage the use of these innovative techniques to support neurologists in early diagnoses. 相似文献
69.
Eric Mayer-Santos Tatjana Maravic Allegra Comba Patricia Moreira Freitas Giovanna Bueno Marinho Claudia Mazzitelli Edoardo Mancuso Nicola Scotti Federica Florenzano Lorenzo Breschi Annalisa Mazzoni 《Molecules (Basel, Switzerland)》2022,27(5)
This study aimed to investigate matrix metalloproteinase (MMP) activity in human dentin using in-situ and gelatin zymography, after at-home and in-office bleaching, related to their clinical exposure times. Dentin specimens (n = 5) were treated with 35% hydrogen peroxide (50 min per session/4 sessions), 10% carbamide peroxide (180 min/21 sessions), or no treatment. All were subjected to in-situ zymography. Dentin slices were, subsequently, obtained, covered with fluorescein-conjugated gelatin, and examined with confocal laser-scanning microscopy. The fluorescence intensity was quantified and statistically analyzed using one-way ANOVA and Bonferroni tests (α = 0.05). Furthermore, gelatin zymography was performed on protein extracts obtained from dentin powder (N = 8 teeth), treated with hydrogen peroxide or carbamide peroxide, with different exposure times (10/50 min for hydrogen peroxide; 252/1260 min for carbamide peroxide). The results of the in-situ zymography showed no statistical differences between the bleached specimens and the control group, with a medium level of gelatinolytic activity expressed in the dentin tubules. The results of gelatin zymography showed an increased expression of pro-MMP-9 in carbamide peroxide groups. The expression of pro-MMP-2 decreased in all the experimental groups. The bleaching treatments performed on the enamel of sound teeth do not influence dentinal enzymatic activity. However, when unprotected dentin tissue is bleached, matrix metalloproteinases are more expressed, particularly when carbamide peroxide is used, proportional to the exposure time. 相似文献
70.
Dr. Anil Reddy Marri Edoardo Marchini Dr. Valentin Diez Cabanes Dr. Roberto Argazzi Dr. Mariachiara Pastore Prof. Stefano Caramori Prof. Carlo Alberto Bignozzi Dr. Philippe C. Gros 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(65):16260-16269
A series of six new Fe(II)NHC-carboxylic sensitizers with their ancillary ligand decorated with functions of varied electronic properties have been designed with the aim to increase the metal-to- surface charge separation and light harvesting in iron-based dye-sensitized solar cells (DSSCs). ARM130 scored the highest efficiency ever reported for an iron-sensitized solar cell (1.83 %) using Mg2+ and NBu4I-based electrolyte and a thick 20 μm TiO2 anode. Computational modelling, transient absorption spectroscopy and electrochemical impedance spectroscopy (EIS) revealed that the electronic properties induced by the dimethoxyphenyl-substituted NHC ligand of ARM130 led to the best combination of electron injection yield and spectral sensitivity breadth. 相似文献