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Bio-oils are an important part of the future energy composition. This review primarily focuses on model compounds, catalysts, and equipment involved in the hydrodeoxygenation (HDO) of bio-oils. Initially, this article reviews the basic physicochemical properties of bio-oils and introduces different upgrading methods. Among them, HDO can effectively facilitate calorific value and improve the acidity and viscosity of bio-oils. Secondly, the basic HDO reaction pathways and proposed catalytic mechanism of various model compounds are summarized to understand the catalytic behavior and structure–performance relationship of the HDO reaction. Subsequently, we review different catalysts used in actual HDO of bio-oils, some of which lead to excellent stability and improved HDO reactivity. Finally, progress in the development of HDO equipment, including fixed bed and ebullated bed reactors in the pilot stage, is reviewed. This review aims to summarize progress in the utilization of the HDO process and provides useful insights for the efficient practical application of bio-oils.

The objective of this research was to investigate the axial compression performance of stone-lightweight aggregate concrete-filled steel tubular (hereafter referred to as SLCFST for simplicity) stub columns. Ten specimens, five circular SLCFST (C-SLCFST) stub columns and five square SLCFST (S-SLCFST) stub columns, were tested using replacement ratios of normal gravel aggregate of between 0% and 100%, in increments of 25%. The influence of replacement ratio on axial compression performance and failure mode, ultimate bearing capacities and peak displacements was analysed. The results were compared, and show that under axial compression loading, strength damage occurs in SLCFST stub columns. The working process of SLCFST stub columns can be divided into four parts: an elastic stage, an elastic-plastic stage, a gentle descent stage and a plastic stage. The ultimate bearing capacities of the specimens were calculated and analysed based on existing design codes. By introducing the influence parameter of normal gravel replacement ratio, mathematical models for predicting the complete stress-strain compression curves of C-SLCFST and S-SLCFST stub columns were developed and verified.

Based on the experiment of 8 steel reinforced concrete T-shaped columns specimens under monotonic static shear load, test value of shear crack load were obtained. Influence on shear crack load because of the shear span ratio, axial compression ratio and stirrup ratio was analyzed, the added coefficient θ of flange and α of steel were introduced. The calculation formula for shear cracking load was given. It is shown that shear cracking load reduces as the shear span ratio and increases with the axial compression ratio increases within a certain range, shear cracking load increases with stirrup ratio increasing, the calculated value of shear cracking load is in good agreement with the experimental data.

On basis of the introduction for the composition of carried-load assistance system and the control mechanism of hydraulic pressure valve for lower extremity exoskeleton, the position control loop is built. The control system is designed by frequency domain method using the PID parameters combined with lead correction network. Simulation results show that the control method can servo the angle of knee joint as human’s natural walk as well as the harmonious of man-machine moment. According to performance test of hydraulic pressure control system, the flow and pressure in piston is analyzed considering different load, the pressure of oil box and movable mode. Test results show that hydraulic pressure valve control system can realize efficiently slow walk carried 30 kilogram load, up and down stairs.

In order to research the mechanical property of angle steel reinforced concrete beams, 7 specimens were designed for pure torsion experiment. And three running parameters which are sectional steel disposition, thickness of concrete cover and concrete strength are taken into consideration. Base on the test, the torque-torsion angle curve, torque-strain curve, cracking torque, ultimate torque and other important data are obtain. The influences of those parameters are analyzed.

In order to reveal the performance of steel recycled concrete composite columns, 6 specimens were designed for axial compression loading experiment. And two factors which are recycled coarse aggregate replacement percentage and slenderness ratio of column are taken into consideration. The bearing capacity and load-displacement curves of composite columns are obtained. Based on the test, the failure patterns and the influence of recycled coarse aggregate replacement percentage and slenderness ratio to axial compression load-bearing capacity are analyzed. In the end, the calculation formula for axial compression load of steel recycled concrete composite columns is presented.

To study the chemical constituents of Wedelia prostrata.Chromatography and spectroscopic analysis were employed to isolate and elucidate the chemical constituents in the plant.Seven compounds were obtained and identified as ent-kaur-16-en-19-oic acid (I), ent-kaur-16alpha, 17-dihydroxy-19-oic acid (II), ent-kaur-15alpha-senecioyloxy-16-en-19-oic acid (III), beta-sitosterol (IV), stigmasterol (V), stigmasterol-3-O-beta-D-glucopyranoside (VI) and n-hexacosanol (VII).Compounds I-III are isolated from this plant for the first time.

In order to study the flexural strength of concrete with different replacement percentage of recycled coarse aggregate, the test were designed and carried out on 33 concrete specimens whose replacement percentage of recycled coarse aggregate are 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, respectively. According to the experiment, the flexural strength of recycled aggregate concrete (RAC) is obtained, and the influence of replacement percentage of recycled coarse aggregate on the flexural strength is analyzed. After the flexural test, the same specimens were used for compression test, and the cubic compressive strength is also acquired. The results show that the flexural strength and cubic compressive strength of the recycled aggregate concrete approximate to those of normal concrete. The ratio of flexural strength to cubic compressive strength is 0.12 for recycled aggregate concrete.