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1.
The title mol­ecule, C13H9ClFN, is substantially planar. The phenyl and 3‐chloro‐4‐fluoro­phenyl rings are on opposite sides of the C=N bond. There is an intermolecular C—H?F short contact with a C?F distance of 3.348 (2) Å and a C—H?F angle of 137.4 (1)°. The mol­ecules are held in layers parallel to the bc plane.  相似文献   
2.
Heterometallic Cluster Complexes of the Types Re2(μ-PR2)(CO)8(HgY) and ReMo(μ-PR2)(η5-C5H5)(CO)6(HgY) (R = Ph, Cy; Y = Cl, W(η5-C5H5)(CO)3) Dinuclear complexes Re2(μ-H)(μ-PR2)(CO)8 and ReMo(μ-H)(μ-PR2)(η5-C5H5)(CO)6 (R = phenyl, cyclohexyl) were deprotonated and reacted as anions with HgCl2 to compounds of the both types Re2(μ-PR2)(CO)8HgCl) and ReMo(μ-PR2)(η5-C5H5)(CO)6(HgCl). The heterometallic three-membered cluster complexes correspond to an isolobal exchange of a proton against a cationic HgCl+ group. For one of the products ReMo(μ-PCy2)(η5-C5H5)(CO)6(HgCl) has been shown its conversion with NaW(η5-C5H5)(CO)3 to ReMo(μ-PCy2)(η5-C5H5)(HgW(η5-C5H5)(CO)3) under substitution of the chloro ligand, par example. The newly prepared compounds were characterized by means of IR, UV/VIS and 31P NMR data. A complete determination of the molecular structure by single crystal analyses was done in the case of Re2(μ-PCy2)(CO)8(HgCl) and of ReMo(μ-PCy2)(η5-C5H5)(CO)6(HgCl) which both are dimer because of the presence of an asymmetric dichloro bridge, and of ReMo(μ-PCy2)(η5-C5H5)(CO)6(HgW(η5-C5H5)(CO)3). The structural study illustrates through comparison the influence of various metal types on an interaction between centric and edge-bridged frontier orbitals in three-membered metal rings.  相似文献   
3.
Titanium dioxide thin films have been synthesized by sol–gel spin coating technique on glass and silicon substrates with and without surfactant polyethylene glycol (PEG). XRD and SEM results confirm the presence of nano-crystalline (anatase) phase at an annealing temperature of 300 °C. The influence of surfactant and annealing temperature on optical properties of TiO2 thin films has been studied. Optical constants and film thickness were estimated by Swanepoel's (envelope) method and by ellipsometric measurements in the visible spectral range. The optical transmittance and reflectance were found to decrease with an increase in PEG percentage. Refractive index of the films decreased and film thickness increased with the increase in percentage of surfactant. The refractive index of the un-doped TiO2 films was estimated at different annealing temperatures and it has increased with the increasing annealing temperature. The optical band gap of pure TiO2 films was estimated by Tauc's method at different annealing temperature.  相似文献   
4.
The initial-boundary-value problem on the semi-infinite interval and on a finite interval for the Burgers equation ut = uxx + 2uxu is solved using a stream function ? and a linearizing transformation w = e?. The transformation reduces the equation to a heat equation with appropriate initial and homogeneous time-dependent linear boundary conditions. One advantage of this method is that we never need to find an explicit expression for ? in our computations.  相似文献   
5.
Control of heat dissipation and transmission to the peri-implant area during intra-oral welding is very important to limit potential damage to the surrounding tissue. The aim of this in vitro study was to assess, by means of thermal infrared imaging, the tissue temperature peaks associated with the thermal propagation pathway through the implants, the abutments and the walls of the slot of the scaffold, generated during the welding process, in three different implant systems. An in vitro polyurethane mandible model was prepared with a 7.0 mm v-shape slot. Effects on the maximum temperature by a single welding procedure were studied using different power supplies and abutments. A total of 36 welding procedures were tested on three different implant systems. The lowest peak temperature along the walls of the 7.0 mm v-shaped groove (31.6 ± 2 °C) was assessed in the specimens irrigated with sterile saline solution. The highest peak temperature (42.8 ± 2 °C) was assessed in the samples with a contemporaneous power overflow and premature pincers removal. The results of our study suggest that the procedures used until now appear to be effective to avoid thermal bone injuries. The peak tissue temperature of the in vitro model did not surpass the threshold limits above which tissue injury could occur.  相似文献   
6.
In this paper, the solitary wave solution of the Boussinesq equation, with power law nonlinearity, is obtained by virtue of solitary wave ansatze method. The numerical simulations are obtained to support the theory.  相似文献   
7.
Alzheimer’s disease (AD) is characterized by working memory (WM) failures that can be assessed at early stages through administering clinical tests. Ecological neuroimaging, such as Electroencephalography (EEG) and functional Near Infrared Spectroscopy (fNIRS), may be employed during these tests to support AD early diagnosis within clinical settings. Multimodal EEG-fNIRS could measure brain activity along with neurovascular coupling (NC) and detect their modifications associated with AD. Data analysis procedures based on signal complexity are suitable to estimate electrical and hemodynamic brain activity or their mutual information (NC) during non-structured experimental paradigms. In this study, sample entropy of whole-head EEG and frontal/prefrontal cortex fNIRS was evaluated to assess brain activity in early AD and healthy controls (HC) during WM tasks (i.e., Rey–Osterrieth complex figure and Raven’s progressive matrices). Moreover, conditional entropy between EEG and fNIRS was evaluated as indicative of NC. The findings demonstrated the capability of complexity analysis of multimodal EEG-fNIRS to detect WM decline in AD. Furthermore, a multivariate data-driven analysis, performed on these entropy metrics and based on the General Linear Model, allowed classifying AD and HC with an AUC up to 0.88. EEG-fNIRS may represent a powerful tool for the clinical evaluation of WM decline in early AD.  相似文献   
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9.
Titanium dioxide (TiO(2)) and silicon dioxide (SiO(2)) thin films and their mixed films were synthesized by the sol-gel spin coating method using titanium tetra isopropoxide (TTIP) and tetra ethyl ortho silicate (TEOS) as the precursor materials for TiO(2) and SiO(2) respectively. The pure and composite films of TiO(2) and SiO(2) were deposited on glass and silicon substrates. The optical properties were studied for different compositions of TiO(2) and SiO(2) sols and the refractive index and optical band gap energies were estimated. MOS capacitors were fabricated using TiO(2) films on p-silicon (100) substrates. The current-voltage (I-V) and capacitance-voltage (C-V) characteristics were studied and the electrical resistivity and dielectric constant were estimated for the films annealed at 200°C for their possible use in optoelectronic applications.  相似文献   
10.
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