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A phytochemical investigation on the whole plant of Paraboea rufescens led to the isolation of a new compound Paraboside C (1) and eight known compounds, which including two phenylpropanoid glycosides (2 and 3), two glycosides (4 and 5), three triterpenoids (6–8), and one ethyl cyclohexanol derivative (9). Their structures were elucidated based on extensive spectroscopic methods (NMR, MS, UV, IR and ECD experiments) and comparison with literature data. Compounds 2 and 5 exhibited significant neuroprotective activities against corticosterone induced PC12 cells, which presenting a dose-dependent effect. The chemotaxonomic significance of the isolated compounds were also been discussed. [Display omitted] • 9 compounds were isolated from the whole plant of Paraboea rufescens. • Compound 1 was a new phenylpropanoid glycoside. • Compounds 3 – 9 were isolated from P. rufescens for the first time. • Compounds 2 and 5 exhibited significant neuroprotective activities. • The chemotaxonomic significance of the isolated compounds were discussed. [ABSTRACT FROM AUTHOR]

• The rupture process of the 2014 M w 6.2 Ludian earthquake was constrained by teleseismic data and more strong-motion data. • The Ludian earthquake ruptured two conjugate faults with strike angles of 77° and 160°, respectively. • The rupture simultaneously took place on two conjugate faults and lasted approximately 10 s. • The shallow dominating slip patch is the main reason for the enormous disaster from the earthquake source perspective. The M w 6.2 Ludian earthquake, struck Yunnan, China on August 3rd, 2014, leading to a complex aftershock distribution and enormous disaster. The Ludian earthquake is well recorded by the China Earthquake Network. The rupture process of the Ludian earthquake is constrained by the more local strong motion data including the LLT station with epicentral distance of ∼2 km and teleseismic body waves and surface waves in this study. The local strong motion data constrained the epicenter's location and rupture process better. Waveform fit of key local strong-motion stations supported that the Ludian earthquake ruptured two conjugate faults with strike angles of 77° and 160°, respectively. The rupture simultaneously took place on two conjugate faults and lasted approximately 10 s. The peak slip, rise time, and average slip rate are 0.63 m, 0.69 s, and 2.12 m/s, respectively. The result shows that the main rupture zone was on the fault with a strike of 160°. The depth of the major slip patch was 0–4 km with a centroid depth of 2 km. It indicates that the shallow slip is the main reason for the enormous disaster from the earthquake source perspective. [ABSTRACT FROM AUTHOR]

Chemical investigation on the fruits of Zanthoxylum motuoense have led to the isolation of a new flavonolignan (1), together with three known flavonoids (2 - 4), as well as five alkylamides (5 – 9). Their structures were determined by NMR, IR, UV, CD spectra and HRESIMS data. The chemotaxonomic significance of these compounds was discussed. The neuroprotective activity of the isolated compounds were evaluated. Compound 6 showed a significant protective effect against corticosterone-induced neuronal damage at 20 μmol/L. [Display omitted] • Nine compounds were isolated from the fruits of Zanthoxylum Motuoense. • Compounds 1 was identified as a new flavonolignan. • All the compounds were isolated from Z. motuoense for the first time. • Alkylamides could be recognized as a typical biomarker for Zanthoxylum genus and Rutaceae family. [ABSTRACT FROM AUTHOR]

The phytochemical study on the whole plant of Lobelia davidii Franch. (Campanulaceae) resulted in the isolation of one new polyacetylene, davidiotylin A (1), one new natural compound, (5 R) N -methyl-5-acetophenone-pyrrolidine-2-one (6), along with six known compounds including lobetyolin (2), choushenpilosulyne A (3), lobetyol (4), fissistigmol A (5), pistaciamide (7), N , N′ -dicoumaroylputrescine (8). Their structures were characterized by the comprehensive analysis of their NMR, IR, UV, ECD spectra and HRESIMS data. All the isolated compounds were reported from L. davidii for the first time. The chemotaxonomic significance of these compounds was discussed. [Display omitted] • Eight compounds were isolated from the whole plant of Lobelia davidii Franch. • Compounds 1 was identified as a new polyacetylene. • Compound 6 was a new natural compound, and its absolute configuration was determined by ECD spectrum. • All compounds were isolated from L. davidii for the first time. • The chemotaxonomic significance of the isolated compounds was discussed. [ABSTRACT FROM AUTHOR]

A phytochemical investigation on the whole plant of Paraboea rufescens led to the isolation of 17 compounds including nine phenylethanoid glycosides (1 – 9), two steroids (10 – 11), two triterpenoids (12 – 13), two dihydroflavones (14 – 15), and two organic acids (16 – 17). Their structures were elucidated by their spectroscopic data analysis. This is the first report of compounds from P. rufescens. The chemotaxonomic significance of P. rufescens and the other species among Gesneriaceae was also discussed. Phenylethanoid glycosides can be recognized as typical biomarkers for the genus Paraboea. • 17 compounds were first isolated from the whole plant of Paraboea rufescens. • Compounds 1 , 3 , 9 , 10 , 12 , and 14–16 were first isolated from the genus Paraboea. • Phenylethanoid glycosides can be recognized as typical biomarkers for the genus Paraboea. • Compounds 13 can serve as biomarkers for the family Gesneriaceae. [ABSTRACT FROM AUTHOR]

Analytical solutions for predicting spring-in angles of U-shaped composite parts generating in rubbery and glassy states are proposed. In the newly developed analytical solutions, the process-induced distortions of web and flange are mathematically converted to spring-in angles within the scope of small deformation theory, and then corresponding analytical expressions of web, corner, flange and total spring-in are separately derived. These new solutions can quantitatively give the correlation of web, corner, flange and total spring-in with material properties-related and geometrical configuration-dependent parameters, and evaluate the spring-in angles of multi-angle ply composite parts just using lamina properties. The reliability of newly proposed analytical solutions is checked by the comparison between the analytically calculated and experimentally measured spring-in angles for unidirectional and quasi-isotropic U-shaped composite parts. Meanwhile, numerical simulations on the U-shaped composite parts with various geometries and layups also provide a favourable agreement with analytical results. • Analytical solutions for spring-in of U-shaped composite parts are proposed. • New solutions can quantify effect of properties and geometry on spring-in angle. • New solutions can evaluate the spring-in angles just via lamina properties. • The reliability of solutions is experimentally and numerically validated. [ABSTRACT FROM AUTHOR]

The synergistic flame retardant system consisted of intumescent flame retardant (IFR) and organic modified attapulgite (OATP) synergist was used to improve the mechanical properties and flame retardancy of continuous glass fibre reinforced polyethylene composites (GFPE). The IFR was composed of ammonium polyphosphate (APP) as acid source and poly(1,3-diaminopropane-1,3,5-triazine-o-bicyclic pentaerythritol phosphate) (PDTBP) as carbon source. The mechanical properties (tensile strength) of GFPE/IFR/OATP were improved by 35%–43% after adding OATP synergist with rod-like fiber structure due to its strengthening and toughening effect on the resin matrix, and the flame retardancy increased first and then decreased with the increase of OATP synergist loading. When 4 wt% OATP synergist was added into GFPE/IFR, the LOI value increased from 29.5% to 31.3% and the flame spread rate significantly reduced. The synergistic flame retardant system of IFR/OATP could form a stable and dense char layer on the surface of glass fibre and weaken the wicking actions of glass fibre. The synergistic flame retardant system of 26 wt% IFR/4 wt% OATP could endow GFPE with best comprehensive performance. [ABSTRACT FROM AUTHOR]

Unidirectional laminated composite plate composed of AS4/8552 prepregs was manufactured with autoclave processing, and the bare and encapsulated FBG sensors were longitudinally embedded into the composite plate along the through-thickness direction to monitor the development of temperature and strain gradient. Before the measurement, the coefficient of temperature sensitivity and axial strain sensitivity of FBG sensors were calibrated, and the results reveal that the coefficient of axial strain sensitivity is a constant but coefficient of temperature sensitivity depends on the magnitude of temperature. Subsequent data analyses on the monitored results by encapsulated FBG sensors show that temperature distribution is relatively uniform inside composite plate but temperature gradient still exists in the through-thickness direction during curing. Meanwhile the monitored results by bare FBG sensors indicate that strain gradient also occurs during curing, and further investigation demonstrates that tool-part interaction is the major cause for the formation of strain gradient within the unidirectional composite plate. [ABSTRACT FROM AUTHOR]

A novel intumescent flame retardant (IFR) system composed of ammonium polyphosphate and poly (1,3-diaminopropane-1,3,5-triazine-o-bicyclic pentaerythritol phosphate) (APP/PDTBP) was mixed with polyethylene to prepare the continuous glass fibre reinforced polyethylene (CGF/PE) unidirectional prepregs by melt impregnation process, and then the CGF/PE/IFR composite laminate were consolidated by hot compression moulding method. The flame retardancy, thermal stability and mechanical properties of CGF/PE/IFR composite laminates were investigated by limiting oxygen index, vertical burning test, cone calorimetric test, thermogravimetric analysis, tensile and flexural strength tests, mode I interlaminar fracture toughness test, and scanning electron microscopy (SEM). The flame retardancy of CGF/PE composite laminates increased with the increase of IFR system loading, which attributes to the formation of intumescent char layer from flame retardants and the weakening of wicking actions of glass fibres. The mechanical properties increased and then decreased with addition of flame retardants, except for the flexural strength with continuous increase. The SEM images showed that IFR system had toughening effect and could improved the strength of fibre-matrix interface. Based on the mechanical properties and the flame retardancy, when the matrix contains 30 wt% IFR system, the CGF/PE/IFR composite laminate had the best comprehensive performance. Image 1 [ABSTRACT FROM AUTHOR]

Transition metal phosphides (TMPs) are regarded as highly efficient electrocatalysts due to highly active surface sites, electrical conductivity, and chemical stability, which result from the high electrocatalytic activity of the M-centers and P-sites. Thus, the aim of our work is to obtain highly efficient TMPs electrocatalysts by a facile and controllable strategy. We used N, S-rich Co/Fe bimetallic metal-organic framework as template to prepare ceramic Co/Fe binary phosphides embedded in N, S, O ternary-doped carbon matrix (CoFeP@NSOC). By means of a facile one-step low-temperature pyrolysis-phosphating approach, the optimized ceramic material CoFeP@NSOC-400 showed remarkable bifunctional electrocatalytic performances in an alkaline electrolyte, which only requires 176 and 240 mV overpotentials to achieve 10 mA cm−2 current density for HER and OER, respectively. Furthermore, when CoFeP@NSOC-400 is loaded on the highly conductive nickel foam (NF) for water splitting, it reaches a current density of 10 mA cm−2 at a low cell voltage of 1.62 V, superior to pure NF and other reported metal-phosphide electrocatalysts, at the same time, CoFeP@NSOC-400 shows negligible performance degradation and a relative current loss of only 4.3% for 40000 s continuous operations. These results indicate CoFeP@NSOC derived by MOFs through pyrolysis-phosphating is an ideal electrocatalysts for energy conversion applications. Nanostructured Co/Fe binary phosphides embedded in N, S, O ternary-doped carbon matrix by facile one-step low-temperature pyrolysis-phosphating approach from a N, S-rich bimetallic MOF to drive water splitting. By adjusting the phosphating temperature, the optimum CoFeP@NSOC-400 exhibits excellent bifunctional electrochemical performances for HER and OER in an alkaline electrolyte. When CoFeP–NSOC-400 is loaded on the foamed nickel for water splitting, a lower voltage 1.62 V is obtained to reach a current density of 10 mA cm−2. This paper proposes a one-step and low-cost phosphating method to obtain nanostructured bimetallic phosphides containing heteroatom doping carbon matrix, showing prominent electrocatalytic performance for water splitting. [Display omitted] • MOFs-derived Co/Fe TMPs embedded in N, S, O ternary-doped carbon matrix. • Co/Fe TMPs were fabricated by one-step low-temperature pyrolysis-phosphating approach. • The optimized TMP is a remarkable bifunctional electrocatalyst for efficient water splitting. [ABSTRACT FROM AUTHOR]

The phytochemical investigation on the leaves and twigs of Zanthoxylum dimorphophyllum Hemsl led to the isolation of a new compound 7-(4′ R -hydroxy-3′,7′-dimethyl-2′ E ,6′-octadienyloxy) coumarin (1) and fourteen known compounds, including nine coumarins (2 – 10), one alkaloid (11), three lignans (12 – 14) and one flavone (15). Their structures were elucidated based on extensive spectroscopic methods (NMR, MS, UV, IR and ECD experiments) and comparison with literature data. The chemotaxonomic significance of the isolated compounds has also been discussed. [Display omitted] • 15 compounds were isolated from the leaves and twigs of Zanthoxylum dimorphophyllum. • Compound 1 was a new coumarin. • Compounds 2 , 3 , 5 , 7–10 and 12 were isolated from Z. dimorphophyllum for the first time. • Chemotaxonomic relationships among Z. dimorphophyllum , the genus Zanthoxylum and the family Rutaceae were discussed. [ABSTRACT FROM AUTHOR]

The phytochemical investigation on the whole plant of Lysionotus pauciflorus led to the isolation of a new flavonoid (1), along with eight known flavonoids (2 – 9), as well as five alkaloids (10 – 14). Their structures were elucidated based on extensive spectroscopic methods (1D and 2D NMR, HRESIMS, IR, and UV experiments), coupled with comparison with literature data. Among these known compounds, compounds 2 , 4 – 6 , 10 – 14 were isolated from L. pauciflorus for the first time. What is particularly exciting is that alkaloid compounds, which possessed indole skeleton, were found in Gesneriaceae plants for the first time. The chemotaxonomic significance of these isolated compounds has also been discussed. The highly oxygenated flavones identified in the plant may be used as chemotaxonomic marker of Lysionotus. [Display omitted] • 14 compounds were isolated from the whole plant of Lysionotus pauciflorus. • Compound 1 was a new flavonoid. • Compounds 2 , 4 – 6 , 10 – 14 were isolated from L. pauciflorus for the first time. • The alkaloids were found in Gesneriaceae plants for the first time. • Highly oxygenated flavones can be recognized as typical biomarkers for the genus Lysionotus. [ABSTRACT FROM AUTHOR]

β-MnO 2 microncube is a novel morphology of microncube with rectangular pyramid. It has been synthesized for the first time via a simple aqueous chemical route under hydrothermal conditions without any templates. When the reaction time is increased from 1 h to 10 h, the crystal type changed from γ-MnO 2 to β-MnO 2 and the morphology changed from an urchin-like shape to a microncube with rectangular pyramid. We propose a possible growth mechanism for intrinsic structural growth mechanism, the evolution process of the β-MnO 2 structure is proposed to involve two main stages. Besides, the electromagnetic properties of the synthesized β-MnO 2 were investigated. It shows that β-MnO 2 has certain dielectric loss properties and an effective absorption bandwidth (reflection loss lower than − 10 dB) of 3.5 GHz was achieved from the β-MnO 2 /paraffin wax composite. [ABSTRACT FROM AUTHOR]

Hypericum monogynum L. (Hypericaceae) has been used as a folk Chinese medicine for the treatment of inflammatory related diseases. Cyclooxygenase-2 (COX-2) is a crucial target for the development of agents to treat inflammation. To search for anti-inflammatory compounds from traditional Chinese medicines, a chemical constituent study along with COX-2 inhibitory activity analysis was performed for this plant. In this study, sixteen chemical monomers, including three undescribed oxidative degradation polycyclic polyprenylated acylphloroglucinols (PPAPs, hypemoins C–E), two undescribed PPAPs (hypemoins A and B), and 11 known compounds, were identified from the flowers of H. monogynum. Their structures were characterized by HRESIMS, NMR techniques, ECD, and single crystal X-ray diffraction. Four flavonoid derivatives showed remarkable COX-2 inhibitory activities, with IC 50 values ranging from 0.220 ± 0.006 to 1.655 ± 0.098 μM. Among these compounds, the possible recognition mechanism between quercetin 3-(6″-O-caffeoyl)-β-3-D-galactoside and COX-2 was predicted by molecular docking analysis. Moreover, the multidrug resistance reversal activities for the selected compounds were evaluated. Sixteen chemical monomers, including three undescribed oxidative degradation polycyclic polyprenylated acylphloroglucinols (PPAPs, hypemoins C–E), two undescribed PPAPs (hypemoins A and B), and 11 phenol derivatives were discovered from the flowers of Hypericum monogynum. Four flavonoids showed remarkably COX-2 inhibitory activities with IC 50 values ranging from 0.220 ± 0.006 to 1.655 ± 0.098 μM. [Display omitted] • Five undescribed compounds were isolated from Hypericum monogynum. • Four flavonoids showed remarkably COX-2 inhibitory activities. • The possible recognition mechanism was predicted by molecular docking. • The multidrug resistance reversal activity was also evaluated. [ABSTRACT FROM AUTHOR]