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Graphical abstract Highlights • Two previously undescribed limonoids and two previously undescribed phenolic acids were isolated from Trichilia sinensis. • One previously undescribed natural phenolic acid dimer was isolated from Trichilia sinensis. • The structures were determined by extensive spectroscopic analysis and chemical techniques. • All the compounds were evaluated for their anti-inflammatory activities and antibacterial activities. Abstract Phytochemical investigation on the twigs and leaves of Trichilia sinensis led to the isolation of two previously undescribed limonoids (i.e. , trichiliasinenoids D and E, 1 and 2), two previously undescribed phenolic acids (3 and 4), and one previously undescribed natural phenolic acid dimer (5), together with 11 known compounds (6 - 16). Their structures were elucidated by extensive spectroscopic analysis (IR, UV, HRESIMS, 1D and 2D NMR) and chemical techniques. The potential anti-inflammatory activities of all the compounds were evaluated in lipopolysaccharide-stimulated RAW 264.7 cells. Among these isolates, compounds 1 , 2 , 6 , and 11 - 13 expressed weak NO inhibition. The antibacterial activities of all the compounds against bacteria were also tested in vitro. Compound 16 exhibited moderate antibacterial activities against Escherichia Coli. [ABSTRACT FROM AUTHOR]

Abstract: The effect of a preformed angle in the lap zone of steel adherends on the stress distribution in adhesively bonded single lap joints was investigated using an elasto-plastic finite element analysis (FEA). The ultimate loads of the joints were determined by shear tests and the failure surfaces of the lap zone were analyzed using scanning electron microscopy (SEM). The results from the numerical simulation showed that all the peak stresses in the mid-bondline of the adhesively bonded single lap joint were reduced as the preformed deflection angle was increased from 0° to 15°. The highest value of the average ultimate load of the experimental joints occurred when the preformed angle was equal to 7° (about 64% higher than the standard one). The SEM images also indicated that the failure mode in the overlap zone of the joint changed from that of a mainly adhesion one to a mixed one as the preformed angle increased. [Copyright &y& Elsevier]

Abstract: The influence of the height and angle of the inner chamfer near the unload ends of the adherends and the elastic modulus of several adhesives on the stress distribution in the single lap joint has been investigated using both the elasto-plastic finite element analysis (FEA) and experimental methods. The results from FEA show that the peak stress in the mid-bondline decreases enormously as the adherends are chamfered with an angle of 30° and a chamfer height through full thickness on the inner side of the adherend. When the chamfer angle and the chamfer height are taken to be constant (h=H and θ=30°), the peak stresses in the fillet near the ends of the adherends decrease gradually as the elastic modulus of adhesives increases while all the peak stresses in the middle part of the overlap increase enormously except in the case of the peel stress. It is certain that the load-bearing capacities of the joints are better with a chamfer height of H and a chamfer angle of 30°. The results obtained from the numerical modeling were in compliance with the experimental tests. [Copyright &y& Elsevier]

Abstract: The elastic finite element analysis (FEA) and the experimental method were used to investigate the effect of the gap, as well as its length, on the stress distribution in both the mid-bondline and the adherend near the interface along the lap zone of adhesively bonded aluminum double-lap joint. The values of the peak stresses distributed in the mid-bondline were increased a little when an 8mm length gap was arranged symmetrically around the center of the lap zone. Both peak stresses and stress at the point close to the edge of the gap in the mid-bondline were increased when the gap length was increased, but the increment of the peak stresses was small when the lap length was not greater than 16mm. The results from the FEA simulation showed that the effect of the gap length on the ultimate load of the joint was small as the gap length was increased. It is supported with the results from the experiments that the ultimate load of the aluminum double-lap joint decreased a little when the gap length was less than 12mm. [Copyright &y& Elsevier]

Abstract: The stress distribution of adhesively bonded metal/metal single lap joints under cleavage loading is analyzed using three-dimensional (3D) elastic–plastic finite element method (FEM). Results show that there exist complicated 3D stress states in cleavage joints, mainly including three-direction normal stress components, and three-direction shear stress components, the values of the latter are far less than that of the former. Moreover, a higher tensile stress exists at the left edge (i.e. near the loaded region of the joints) of adhesive layer along bondline, however, a compressive stress at the right edge (i.e. far from the loaded region of joints) along bondline. Furthermore, effects of thickness, elastic modulus and Poisson''s ratios of adhesives on 3D stress state of adhesive layer of cleavage joints also have been investigated. However, observations have been made in particular on normal stress components at the interfaces, which provides useful insight into the 3D nature of the problem. [Copyright &y& Elsevier]

The phenomenon of work hardening in the bonded region of steel adherends has been studied, and the effect of adherends recycling on the shear strength of a single lap joint is analyzed in this paper. The values of hardness on the surfaces of failed joints were measured after being simply treated (removing the adhesive layer by solvent) before the specimen preparation next time. Mild steel or pure copper sheet and an epoxy adhesive were used to prepare the single lap joints and the same couple of adherend pieces underwent three or four times of strength and hardness tests. The results obtained show that the evident hardness change occurred after the adherends passed their first or second strength testing and most of the points tended to increase their values of hardness as the tests were performed. It may be due to the contribution of the stress concentration during loading, and the residual stress occurred after the adherends unloading. The results obtained also show that the increase of hardness occurring in the bonded zone is greater than that on the face opposite to the bonded region. The distribution of micro-hardness was verified by the strain gauges testing method. [Copyright &y& Elsevier]

The effect of fillet containing metallic components on the strength of adhesively bonded single lap joints has been undertaken by alternating the shape and size of metallic components as a part of fillet or whole fillet at the end of the joints. Mild carbon steel and epoxy structural adhesive were used to prepare single lap-shear joints. Three types of steel components or fillets were embedded in the joints. Two of them were in shapes of wire and the remaining was a column in section of an isosceles right-angled triangle. After their failure, all specimens were analyzed by the electron probe microanalysis (EPMA) meter to explain the failing procedure of single lap joints. The results obtained from experiments show that the shear strength increased about 45% by embedding steel wire in the fillets. Its EPMA image also gives more fine toughness pits on the fracture surface and other tracks of adhesion failure while in the cases of fillets without metallic component or with a thorough metal column as fillets show the micro-appearance of being torn off. It is evident that the existence of the metallic component in the shape of round bars may improve the action of the fillets in the process of shear strength testing and failure. [Copyright &y& Elsevier]

Abstract: The effect of the length and depth of a parallel slot as well as the elastic modulus of the adhesive on the stress distribution at the mid-bondline and in the adherend was investigated using the elastic finite element method. The results showed that the peak stress in mid-bondline decreased markedly when there were two of parallel slots located in the outside of the adherend, corresponding to the middle part of the lap zone and the original low stress in this zone of the joint increases. The peak stress decreased at first, and then increased again as the length of the parallel slot was increased. The stress distribution in the mid-bondline at the position corresponding to the parallel slot decreased significantly as the depth of the parallel slot was increased. The high peak stresses caused by the tensile load occurred close to the edge of the parallel slot in the adherend. Almost all the peak values of stresses at the mid-bondline increased when the elastic modulus of the adhesive was increased. The effect of the parallel slot on the peak stress at the mid-bondline with a low elastic modulus adhesive was negligible, but the peak stress decreased markedly for adhesives with a high elastic modulus. [Copyright &y& Elsevier]

Eleven previously uncharacterized steroids, along with three analogs were isolated from Aglaia lawii leaves. Their structures were definitely characterized by the methods of NMR, MS, IR, ECD and X-ray crystallography study. Among these unreported compounds, 3-epi-dyscusin C, 3-epi-lansisterone E and (Z)-2 α -hydroxyaglawone were C-21 pregnane steroids incorporating a highly oxygenated ring A, while others were Δ5-3 β -hydroxy-7-ketosteroids bearing different ring D and C-17 aliphatic chains. All isolates were evaluated for nitric oxide (NO) inhibitory activities. 3-Epi-dyscusin C, 3-epi-lansisterone E, (Z)-2 α -hydroxyaglawone and 17(20) E -dyscusin B showed significant anti-inflammatory activities with IC 50 values of NO inhibition less than 10 μ M (in the range from 4.47 ± 0.36 to 7.67 ± 0.46 μ M). Image 1 • Eleven previously undescribed steroids were isolated from Aglaia lawii leaves. • The structure of 3-epi-dyscusin C was confirmed by X-ray crystallography study. • All isolated compounds were evaluated for nitric oxide inhibitory activities. • Some of steroids exhibited significant NO inhibitory activities. [ABSTRACT FROM AUTHOR]

• Fiscal funding has no significant link with teacher salary and child-teacher ratio. • Fiscal funding has significantly positive association with instructional management. • Instructional management mediates the link of fiscal funding with classroom quality. • It is important to utilize resources to support teacher and instructional management. The present study examined the interactive effects of organizational resources on classroom quality of 90 Chinese kindergartens using principal and teacher questionnaires and observational ratings of classroom practices. The results revealed that the average monthly teacher salary, child-teacher ratio and instructional management had significant direct associations with classroom quality, and the three-year average fiscal funding had a significantly positive association with instructional management and significant indirect association with classroom quality via the mediation of instructional management. The findings suggested that the allocation and organization of resources for teachers and instructional management in support of teachers and teaching are important for improving classroom quality, and that kindergarten leaders play a critical role in effectively transforming available resources into quality classroom practices. [ABSTRACT FROM AUTHOR]