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In this paper, Bi-doped hydroquinone (HDQ) molecularly imprinted TiO2(Bi-HDQ-TiO2) with the synthesis of Bi2Ti2O7–TiO2as the main ingredient was developed. Using HDQ as an imprinted molecule, Bi(NO3)3-5H2O was introduced into the synthesis of Bi-HDQ-TiO2, which revealed that bismuth oxide was protected by HDQ in the temperature range of 0–450 °C, and during the gradual increase of the temperature up to 550 °C, the HDQ eluted completely, then the surrounding TiO2was nucleated by bismuth oxide and bonded with the bismuth oxide, causing all of them to be transformed into Bi2Ti2O7. The excited electrons of the catalyst could be transported efficiently in various surface interfaces, meanwhile inhibiting the complexation of photogenerated carriers, thereby improving the efficiency of photocatalysis. A degradation efficiency of 96.35% of HDQ was achieved under 30 min UV irradiation, indicating that the candidate material has a promising future application in environmental purification or human health.

This letter presents a novel multifunctional active polarizer that can efficiently transform incident horizontal linear polarization (HP) waves into four different reconfigurable polarization modes, including HP, vertical linear polarization, left-hand circular polarization, and right-hand circular polarization modes, over a wideband range. The proposed unit has low-profile structure, and utilizes two PIN diodes to achieve phase shifts of 180° and 90° in u and v directions, allowing for quad-polarization conversion with a shared band of 8.7–11.17 GHz. Finally, a sample prototype was fabricated, and the simulated and measured results are in good agreement, proving that this design has practical applications for wireless communication systems.

It has been partially shown that salicylic acid (SA) as an imprinting molecule can produce better photocatalytic effect, while the contribution of SA as a molecular imprinting and degradation substrate is not clear. Herein, SA-TiO2was prepared by a one-step molecular imprinting method using SA as the imprinting molecule and tetra-n-butyl titanate as the precursor, which was analyzed by XRD, UV–Vis, SEM, TEM-EDS, XPS, PL, FT-IR, EIS, and photocurrent response. The results shown that 1.5SA-TiO2had the best electrochemical properties and therefore the best photoelectric effect. Moreover, the decolorization rates of SA within 30 min were 49.25% and 62.69% for TiO2and SA-TiO2, respectively, indicating that the synthesized SA-TiO2had better photocatalytic performance and could be applied in future scenarios for the efficient degradation of SA wastewater.

Carbon fiber reinforced polymer (CFRP) materials are important reinforcing substances which are widely used in the shear strengthening of seismic-damage steel reinforced concrete (SRC) frame structures. To investigate the shear strength of SRC frame columns strengthened with CFRP sheets, experimental observations on eight seismic-damaged SRC frame columns strengthened with CFRP sheets were conducted at Yangtze University and existing experimental data of 49 SRC columns are presented. Based on the existing experiments, the theories of damage degree, zoning analysis of concrete, and strengthening material of the column are adopted. To present the expression formula of the shear strength of SRC frame columns strengthened with CFRP sheets, the contributions of strengthening material and transverse reinforcement to shear strength in the truss model are considered, based on the truss-arch model. The contribution of arch action is also considered through the analysis of the whole concrete and that of the three zones of the concrete are also considered. The formula is verified, and the calculated results are found to match well with the experimental results. Results indicate that the proposed whole analysis model can improve the accuracy of shear strength predictions of shear seismic-damaged SRC frame columns reinforced with CFRP sheets.

We study the effect of calcination temperatures on photocatalytic dye degradation performance of bismuth nitrate materials using paper microzone method. The calcination forms different photoactive bismuth compounds such as α-Bi2O3, Bi5O7NO3, and (BiO)4CO3(OH)2, which are responsible for photocatalytic activity. We show that using basic magenta as a model pollutant is beneficial to more accurately determine the effects brought by different quenching agents on photocatalytic activity, compared with salicylic acid, which is a colorless and refractory pollutant. Our results may provide important insights into developing a model system to study the photocatalytic activity of various catalytic systems and to develop effective water treatment methods.

There is an enlightening phenomenon in nature where mussels can purify water following swallowing microorganisms, debris, gravel, etc. Inspired by this phenomenon, we simulated the shell-pearl structure of a clam, and developed a unique method to synthesize Bi2O3intercalated bismuth titanate and molecularly imprinted TiO2microbead composites. Salicylic acid (SA) as an organic molecule (also target pollutant) plays a key role in the protection and formation of Bi2O3, which is key to obtaining the structure of mussel shell. The open shell-pearl bionic structure enables efficient transport of excited electrons across a variety of surface interfaces, while suppressing the complexity of photogenerated carrier that drives photocatalytic efficiency. Results show that the synthesized shell-pearl type catalyst achieved 92.54% degradation efficiency of salicylic acid under 30 min UV irradiation, which is 1.97 times higher than that of TiO2. The high degradation efficiency indicate that pearl type catalyst has promising applications in future environmental purification as well as human health.

To study the anchoring performance of chemical anchor bolts in building curtain wall, anchoring performance affected by chemical anchoring in concrete grade and anchor bolt diameter were considered. Based on the existing code, 48 standard specimens were made. After analysing the drawing force and the load-displacement curve, the results revealed that when the concrete strength grades are the same, the drawing force of specimen increases while the increasing of chemical anchor bolt diameter; when the chemical anchor bolts have the same diameter, the drawing force of each specimen increases while the increasing of the concrete strength grades; when the concrete strength grade is C40 and the chemical anchor bolt diameter is M14, the concrete splitting damage degree of specimen is the weakest.

To study the anchoring behavior of chemical anchors under repeated loading, 33 test pieces were designed and fabricated based on the specifications. Each 3 test pieces were 1 set, that is, 1 set of comparative test pieces and 10 sets of test pieces, respectively, for static force. Bonding and anchoring performance tests for loading and reloading. Through the analysis of the test phenomena and results, the following conclusions are drawn: when the loading load exceeded 0.9 times the ultimate bearing capacity of the anchor; when the loading load was equal to 0.6 or 0.75 times, the test piece would undergo splitting damage after the set number of loading times, and its bearing capacity would increase. As the number of loading increased, the energy consumption would gradually decrease, and the decreasing amplitude would gradually increase. Compared with constant amplitude loading and variable amplitude loading, it is found that the slip value of variable amplitude loading increased by 42.1% and the bearing capacity decreased by 12%, which indicated that variable amplitude loading has a great influence on the bonding and anchoring performance of specimens.