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Purpose The purpose of this study is to evaluate the effect of graphene, basalt flakes and their synergy on the corrosion resistance of zinc-rich coatings. As the important heavy-duty anticorrosion coatings, zinc-rich coatings provided cathodic protection for the substrate. However, to ensure cathodic protection, a large number of zinc powder made the penetration resistance known as the weakness of zinc-rich coatings. Therefore, graphene and basalt flakes were introduced into zinc-rich coatings to coordinate its cathodic protection and shielding performance. Design/methodology/approach Three kinds of coatings were prepared; they were graphene modified zinc-rich coatings, basalt flakes modified zinc-rich coatings and graphene-basalt flakes modified zinc-rich coatings. The anticorrosion behavior of painted steel was studied by using the electrochemical impedance spectroscopy (EIS) technique in chloride solutions. The equivalent circuit methods were used for EIS analysis to obtain the electrode process structure of the coated steel system. Simultaneously, the corrosion resistance of the three coatings was evaluated by water resistance test, salt water resistance test and salt spray test. Findings The study found that the addition of a small amount of graphene and basalt flakes significantly improved the anticorrosion performance of coatings by enhancing their shielding ability against corrosive media and increasing the resistance of the electrochemical reaction. The modified coatings exhibited higher water resistance, salt water resistance and salt spray resistance. The graphene-basalt flakes modified zinc-rich coatings demonstrated the best anticorrosion effect. The presence of basalt scales and graphene oxide in the coatings significantly reduced the water content and slowed down the water penetration rate in the coatings, thus prolonging the coating life and improving anticorrosion effects. The modification of zinc-rich coatings with graphene and basalt flakes improved the utilization rate of zinc powder and the shielding property of coatings against corrosive media, thus strengthening the protective effect on steel structures and prolonging the service life of anticorrosion coatings. Originality/value The significance of developing graphene-basalt flakes modified zinc-rich coatings lies in their potential to offer superior performance in corrosive environments, leading to prolonged service life of metallic structures, reduced maintenance costs and a safer working environment. Furthermore, such coatings can be used in various industrial applications, including bridges, pipelines and offshore structures, among others.

Background: Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by abdominal pain, diarrhea or constipation, and changes in defecation patterns. No organic disease has been found to explain these symptoms by routine clinical examination. This study aims to investigate the efficacy and safety of acupuncture therapy for IBS patients based on conventional treatments. We also want to explore the optimal acupoint combination recommended for IBS and clarify the clinical advantage of "multi-acupoint co-effect and synergistic effect".Methods and analysis: A total of 204 eligible patients who meet the Rome IV criteria for IBS will be randomly allocated to receive different acupuncture. Each patient will receive 12 acupuncture treatments over four weeks and will be followed up for four weeks. The primary outcome is the IBS-symptom severity score (IBS-SSS). The secondary outcomes include the Bristol stool form scale(BSFS), the work and social adjustment score (WSAS), the IBS-quality of life (IBS-QOL), self-rating anxiety scale (SAS), and the self-rating depression scale (SDS). Both the primary outcome and the secondary outcomes measures are collected at baseline, 2 weeks, and 4 weeks of the intervention, 6 weeks, and 8 weeks after the intervention.Ethics and dissemination: The entire project has been approved by the ethics committee of Beijing University of Chinese Medicine ( 2020BZYLL0903 ) .Discussion: This is a multicenter randomized controlled trial for IBS in China. This may shed light on the efficacy of acupuncture as an alternative to IBS. The results of the trial will be disseminated in peer-reviewed publications. Trial registration: Chinese Clinical Trials Register, ID: ChiCTR2000041215.First registered on 12 December 2020. http://www.chictr.org.cn/.

Background Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by abdominal pain, diarrhea or constipation, and changes in defecation patterns. No organic disease is found to explain these symptoms by routine clinical examination. This study aims to investigate the efficacy and safety of acupuncture therapy for IBS patients compared with those of conventional treatments. We also aim to identify the optimal acupoint combination recommended for IBS and to clarify the clinical advantage of the “multiacupoint co-effect and synergistic effect.” Methods and analysis A total of 204 eligible patients who meet the Rome IV criteria for IBS will be randomly stratified into acupuncture group A, acupuncture group B, or the control group in a 1:1:1 ratio with a central web-based randomization system. The prespecified acupoints used in the control group will include bilateral Tianshu (ST25), Shangjuxu (ST37), Neiguan (PC6), and Zusanli (ST36). The prespecified acupoints used in experimental group A will include bilateral Tianshu (ST25), Shangjuxu (ST37), and Neiguan (PC6). The prespecified acupoints used in experimental group B will include bilateral Tianshu (ST25), Shangjuxu (ST37), and Zusanli (ST36). Each patient will receive 12 acupuncture treatments over 4 weeks and will be followed up for 4 weeks. The primary outcome is the IBS-Symptom Severity Scale (IBS-SSS) score. The secondary outcomes include the Bristol Stool Form Scale (BSFS), Work and Social Adjustment Score (WSAS), IBS-Quality of Life (IBS-QOL), Self-Rating Anxiety Scale (SAS), and Self-Rating Depression Scale (SDS) scores. Both the primary outcome and the secondary outcome measures will be collected at baseline, at 2 and 4 weeks during the intervention, and at 6 weeks and 8 weeks after the intervention. Ethics and dissemination The entire project has been approved by the ethics committee of the Beijing University of Chinese Medicine (2020BZYLL0903). Discussion This is a multicenter randomized controlled trial for IBS in China. The findings may shed light on the efficacy of acupuncture as an alternative to conventional IBS treatment. The results of the trial will be disseminated in peer-reviewed publications. Trial registration Chinese Clinical Trials Register ChiCTR2000041215. First registered on 12 December 2020. http://www.chictr.org.cn/.

In this work, by combining the superiority of polyoxometalates (POMs) and catalytic single-metal site Co of metalloporphyrin, a series of mixed-valence POM-based metal-organic frameworks (MOFs) composites is synthesized by a post-modification method. The electron-transfer property of POM@PCN-222(Co) composite is significantly enhanced owing to the directional electron-transfer from POM to single-metal site Co in PCN-222(Co). In particular, H-POM@PCN-222(Co) gives a high Faradaic efficiency of 96.2% for electroreduction of CO2 into CO and good stability over 10 h. DFT calculations confirm that the directional electron transfer, which accelerates the multi-electron transfer from the electrode to active single-metal site Co, enriches the electron density of the Co center, and ultimately reduces the energy of the rate-determining step, thus increasing the catalytic activity of CO2 reduction reaction (CO2 RR). This work therefore suggests some new insight for the design of efficient electrocatalysts for CO2 RR.

The solid–liquid equilibria in quaternary system Na2B4O7–Na2SO4–NaBr–H2O and its ternary subsystem Na2B4O7–NaBr–H2O at 323 K were studied with the method of isothermal solution saturation. The solubilities of salts and equilibrium solid phases in the two systems were determined. The solubility diagram of the ternary system has one invariant point, two univariant curves and two fields of crystallization [Na2B4O7·10H2O and NaBr·2H2O]. The solubility diagram of the quaternary system has one invariant point, three univariant curves, and three crystallization fields, where the equilibrium solids are Na2B4O7·10H2O, Na2SO4 and NaBr·2H2O, respectively. According to our experimental data, the solubility of NaBr·2H2O is highest among the three salts, and that of Na2B4O7·10H2O is lowest. Therefore, the field of crystallization of Na2B4O7·10H2O(s) in ternary or quaternary system is larger than others. The addition of sodium bromide leads to rapid decrease of the solubility of Na2B4O7·10H2O(s).

The velocity and amplitude of elastic wave in the rock mass are dependent on the physical and mechanical properties, as well as the structural and stress state of rock mass. The elastic wave testing technique has become one of the most important approaches in geological engineering and rock mechanics. In order to enhance the analysis and application of elastic wave testing technique, the present paper investigates the elastic wave propagation pattern both in laboratory and in field. The lab tests focus on wave velocity in rock mass and the field work focus on the measurement of longitudinal wave velocity by using double-service elastic wave test. The field tests also include the testing of the roadway surrounding rock loose circle on the edge of underground chamber construction site. The study profiles the rock mass’s elastic wave dynamic characteristics, clarifies the rock mass structures, assess the property of the rock mass surrounding the subway. All these are of great significance to the underground chamber and tunneling engineering design and construction.

Poly-2, 5-dimethoxyaniline (PDMA) coating was successfully prepared by electrochemical method on the surface of active carbon (AC) electrodes in oxalic acid aqueous solution. The resulted coating was hydrolyzed to produce poly-2,5-dihydroxyaniline (PDHA) to enhance the capacitance of the composite electrode. Scanning electron microscope (SEM), cyclic voltammetry (CV), galvanostatic charge/discharge test, and electrochemical impedance spectroscopy (EIS) were used to investigate the properties of these electrodes. A comparative analysis on the electrochemical properties of bare-carbon electrode was also conducted under similar conditions. The specific capacitance of the PDHA/AC composite electrode was 947.04 F•g-1 between 0.0 and 1.0 V at a current density of 3.0 mA•cm-2 in 0.5 M H2SO4 electrolyte. The capacitance retention of composite electrode was about 89.2% during 700 charge-discharge cycles.

Polyaniline (PANI) was deposited on the glassy carbon electrode in organic electrolyte. The deposition mechanism and properties of resulted PANI were characterized with Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Electrochemical Impedance Spectroscopy (EIS). The results show that: the polymerization of PANI can carry in a relatively high potential (2.4V), and the electrochemical deposition mechanism of PANI at high potential in organic electrolyte is different from that in inorganic system due to the low conductivity and diffusion coefficient of organic electrolyte. The electro-conductivity of PANI is good in the range of 0.2~0.8V which is wider than that reported in inorganic electrolyte.

The solubilities and densities of the solution in the quaternary system Na2B4O7−Na2SO4−K2B4O7−K2SO4−H2O at 288 K were investigated using the method of isothermal dissolution equilibrium. The solid−liquid stable equilibria in the quaternary system Na2B4O7−Na2SO4−K2B4O7−K2SO4−H2O at 288 K were studied experimentally. On the basis of experimental data, the stable phase diagram of the quaternary system was plotted. In the solubility diagram of the quaternary system Na2B4O7−Na2SO4−K2B4O7−K2SO4−H2O at 288 K, there are three invariant points, seven solubility isotherm curves, and five crystallization regions, which correspond to borax (Na2B4O7·10H2O), potassium tetraborate (K2B4O7·4H2O), mirabilite (Na2SO4·10H2O), arcanite (K2SO4), and glaserite (Na2SO4·3K2SO4). It can be found from the experimental results that sulfates have bigger solubilities than borates in the quaternary system Na2B4O7−Na2SO4−K2B4O7−K2SO4−H2O at 288 K.

In this study, polyaniline (PANI) was prepared by electrochemical method on the surface of active carbon (AC) electrodes. The physical and electrochemistry properties of AC/PANI composite compared with pure AC electrode were investigated by scanning electronic microscope (SEM), galvanostatic charge/discharge test and electrochemical impedance spectroscopy (EIS). The AC/PANI composite electrodes showed much higher specific capacitance (624 F•g-1), better power characteristics and were more promising for application in capacitor than pure AC electrodes.

Heparin affects both dermal fibroblast proliferation and collagen and may mediate these effects by altering the levels of transforming growth factor-beta1 (TGF-beta1) production and TGF-beta1 mRNA expression as a wound healing modulator. The purpose of this study is to probe the effect of heparin on TGF-beta1 and TGF-beta1 mRNA production by human normal skin and hyperplastic scar fibroblasts. This research investigates the effect of heparin on TGF-beta1 and TGF-beta1 mRNA production by human normal skin and hyperplastic scar fibroblasts with exposure to 0 microg/mL, 100 microg/mL, 300 microg/mL, or 600 microg/mL heparin for 24, 48, 72, or 96 hours in a serum-free in vitro model. Levels of TGF-beta1 in the supernatants and TGF-beta1 mRNA expression of fibroblasts were determined by enzyme-linked immunosorbent assay (ELISA) and real time RT-PCR, respectively. Heparin (300 microg/mL and 600 microg/mL) stimulated TGF-beta1 production by normal skin (26% to 83%) and hyperplastic scar fibroblasts (63% to 85%), with statistical significance (P < 0.05) at various time points. Heparin (300 microg/mL and 600 microg/mL) also stimulated TGF-beta1 mRNA expression by normal skin (12% to 53%) and hyperplastic scar fibroblasts (33% to 52%), with statistical significance (P < 0.05) at various time points. These effects of heparin on normal skin and hyperplastic scar fibroblasts may have implications for hyperplastic scar formation and wound healing in vivo.