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•An Al-based MIC (EF@EMOF) was prepared via electrospinning combining with in situ growth technique.•Obtained MIC has significantly increased heat release and burning rate.•The ...etching reaction avoids the sintering and improves combustion efficiency.
Combustion is a kind of reacting process involves fluid mechanics and chemical reactions at the same time. In the past decades, little attention has been paid to the improvement on the heat and mass transfer rate of EMs, especially for metastable intermixed composites (MICs). In this paper, an Al-based MIC (EF@EMOF) with modified chemical kinetics as well as improved heat and mass transfer rate was prepared by precisely designing the reaction process and introducing energetic metal organic frameworks (EMOF) with high specific surface area as the reactants. The overall reaction process includes the activation of n-Al by eliminating Al2O3, decomposition of EMOF producing metal oxide, followed by exothermic reactions between the activated n-Al with metal oxide and PVDF. Results show that obtained MIC has significantly increased heat release (3464 J g−1), burning rate (more than 5 times faster than that of mechanically mixed one), and improved combustion efficiency. Furthermore, it is found that the decomposition of EMOF as well as the etching reaction generates massive gas products on the interface layer which avoid the sintering and form lots of holes. Those holes, in return, provide new channels for the further reaction, thus significantly improving the energy output and chemical reaction kinetics.
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•Formulation of PVDF/CuO/Al is optimized on the basis of maximum heat of reaction.•Electrospinning is employed to fabricate high solid-loading MICs based on PVDF.•Electrospinning and ...doping of GO can improve the density, heat of reaction, etc.
In this paper, the electrospinning technique has been employed to fabricate PVDF/CuO/Al nanocomposites, where the formulation was optimized on the basis of maximizing the reaction heat with increased efficiency. The graphene oxide (GO) has also been used as both lubricant and catalyst, which is well dispersed inside the PVDF matrix by the electrospinning process as well. It has been found that the smooth PVDF nano-fibers could be fabricated with GO content of 0.5 wt%, where the Al and CuO nanoparticles are also uniformly loaded. In comparison with the n-CuO/n-Al and PVDF/CuO/Al prepared by conventional mechanical mixing method, the GO-doped PVDF/CuO/Al nanocomposites via electrospinning improved heat of reaction, density as well as anti-oxidation capability. In addition, the electrospinning technique and doping of 0.5 wt% of GO can improve the reaction efficiency of PVDF/CuO/Al nanocomposites since they contribute to dispersion of components and homogeneous structure fabrication.
Searching for the coexistence of a wide energy gap (E g > 3.5 eV) and a large second-harmonic generation efficiency (d ij > 0.6 × AgGaS2) for noncentrosymmetric (NCS) materials in the IR nonlinear ...optical (NLO) field is highly desirable but still remains a huge challenge because of the incompatibility between them. To address this issue, a new salt-inclusion chalcogenide, namely, Ba4Cl2ZnGa4S10, has been designed and successfully synthesized by a chemical multisubstitution approach with chalcopyrite-type AgGaS2 (AGS) as the template. Ba4Cl2ZnGa4S10 adopts the NCS space group I4̅ with lattice dimensions a = b = 8.2882(4) Å, c = 15.1693(9) Å, V = 1042.04(9) Å3, and Z = 2. The structure is constructed with corner-sharing supertetrahedral Ga4S108– clusters (T2) and ZnS46– tetrahedra (T1) to form a three-dimensional open ZnGa4S106– diamond-like framework, which is further interpenetrated with charge-balanced Ba2+ and Cl–. Remarkably, the title compound not only retains the large d ij (1.1 × AGS) but also possesses a wide E g (ca. 3.85 eV) corresponding to an ultrahigh laser-induced damage threshold (LIDT = 51 × AGS), demonstrating that it achieves the key indexes as a promising IR-NLO candidate. Furthermore, density functional theory (DFT) analysis has assisted the comprehension of the structure–property relationships. Both the experimental and DFT calculation results indicate the practicability of such a chemical multisubstitution approach to design excellent IR-NLO materials, that is, breaking the incompatibility between a wide E g and a large d ij.
A lot of efforts have been devoted to enhance the outputs of triboelectric nanogenerators (TENGs) via optimizing the friction materials in recent years. Here, the modified organic polystyrene (PS) ...microspheres embedded Poly(vinylidene fluoride)-co-trifluoroethylene P(VDF-TrFE) composites are developed to construct lotus-leaf surface microstructure and enhance the permittivity of P(VDF-TrFE). Besides, owing to the rich positively charged -NH3 groups of the hexadecyl-trimethyl-ammonium-bromide (CTAB) in the solvent, the surface potential of composites is significantly improved by CTAB modified PS microspheres. Coupling of designed surface microstructure, high permittivity, and enhanced surface potential, the TENG assembled by P(VDF-TrFE) (+) and Polytetrafluoroethylene (PTFE, -) exhibits considerable outputs (the short-circuit current density and peak power density are 47.45 mA/m2 and 7.88 W/m2, respectively), much higher than those of pristine P(VDF-TrFE) and unretouched PS/P(VDF-TrFE). In the applications, 413 LEDs in series can be lighted up directly by the TENG without energy storage. A smart mouse pad is also proposed to work as the self-powered sensor to detect typical mouse motions. This research provides a comprehensive solution to optimize the positive friction material in simple and feasible methods of surface/interface design and surface potential regulation.
This research provides a simple and feasible method of embedding CTAB modified PS microspheres into the P(VDF-TrFE) matrix to optimize the positive friction material of TENGs from surface microstructure, dielectric constant, and surface potential viewpoints simultaneously. Display omitted
•A facile strategy of constructing a lotus-leaf microstructure is proposed.•The incorporation of PS microspheres into the polymer modulates the permittivity by MWS polarization.•A cationic modifier CTAB is used to promote the surface potential of the tribo-positive layer.
In comparison with the numerous studies that have centered on developing molecular frameworks for the functionalization of fluorescent materials, less research has addressed the influence of the side ...chains, despite such appendages contributing significantly to the properties and applications of fluorescent materials. In this work, a new series of cationic fluorescent probes with AIE characteristics have been developed, which exhibit unique sensitivity for charge-diffusion anions, namely HSO3−, via the interactions of ions and the cooperation of the controllable hydrophobicity. The impact of the alkyl chain length attached at the cationic probes suggested that the fluorescent intensity and sensitivity of the probes could be partially enhanced by adjusting their aggregation tendency through the action of the hydrophobic effect under aqueous conditions. DLS and SEM images indicated that different particle sizes and new morphologies of the probes were formed in the anion-recognition-triggered self-assembly process, which could be attributed to the composite effect of electrostatic actions, Van der Waals forces and π-π stacking.
Background
Nodal-skip metastasis (NSM) is found in esophageal squamous cell carcinoma (ESCC), but its prognostic role is controversial. This study aimed to investigate the prognostic value of NSM for ...thoracic ESCC patients.
Methods
Categorization of NSM was according to the N groupings of Japan Esophagus Society (JES) staging system, which is dependent on tumor location. Using the Kaplan–Meier method and Cox-regression analysis, this study retrospectively analyzed the overall survival (OS) for 2325 ESCC patients after radical esophagectomy at three high-volume esophageal cancer centers. Predictive models also were constructed.
Results
The overall NSM rate was 20% (229/1141): 37.4% in the in upper, 12.9% in the middle, and 22.2% in the lower thoracic ESCC. The patients with NSM always had a better prognosis than those without NSM. Furthermore, NSM was an independent prognostic factor for thoracic ESCC patients (hazard ratio HR, 0.633; 95% confidence interval CI, 0.499–0.803;
P
< 0.001). By integrating the prognostic values of NSM and N stage, the authors proposed the new N staging system. The categories defined by the new N staging system were more homogeneous in terms of OS than those defined by the current N system. Moreover, the new N system was shown to be an independent prognostic factor also for thoracic ESCC patients (HR, 1.607; 95% CI, 1.520–1.700;
P
< 0.001). Overall, the new N system had slightly better homogeneity, discriminatory ability, and monotonicity of gradient than the current N system.
Conclusions
This study emphasized the prognostic power of NSM and developed a modified node-staging system to improve the efficiency of the current International Union for Cancer Control (UICC)/American Joint Committee on Cancer (AJCC) N staging system.
Removal of adipose tissues located behind the left innominate vein and at the aortocaval groove is technically complex for minimally invasive extended thymectomy. The study describes the technical ...tips of the subxiphoid robotic procedure to remove these adipose tissues. Extended thymectomy by the presented procedure was performed in 39 patients, and 6 patients were diagnosed with ectopic thymic tissues behind the left innominate vein. Satisfactory short-term surgical outcomes demonstrated that dissection of adipose tissues located between mediastinal major vessels is technically feasible and safe by this novel procedure.
