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The marine environment is a harsh corrosive one for many materials. Marine corrosion will seriously reduce the service life of the material, damage the function of the material, and cause a serious waste of resource. In marine engineering, steel and concrete materials are the most widely used. Among them, wharf steel pipe piles are very important marine engineering facilities, and their corrosion conditions have a great impact on the safe use for marine facilities. In this paper, the corrosion status , anti-corrosive technologies and their application effect of some wharf steel pipe piles at home and abroad were investigated. Besides, the effective protection measures were put forward.

Porphyrins have been widely used in designing photocatalyst systems. However, finding an effective strategy to improve the intrinsic photocatalytic activity of porphyrin molecules remains a challenge. Here, two new porphyrins, meso-tetra(5-carboxyfuryl)porphyrin (H2TCFP) and meso-tetra(5-carboxythienyl)porphyrin (H2TCTP), were successfully synthesized and compared with meso-tetra(m-carboxyphenyl)porphyrin (H2TmCPP), to clarify the influence of the organic unit bridging the carboxyl acid group with the porphine ring on the photocatalytic activity of porphyrin for H2 evolution from water splitting. The H2 evolution rates of 10.8 mmol g−1 h−1 observed for H2TCFP and 9.7 mmol g−1 h−1 for H2TCTP are both larger than 8.0 mmol g−1 h−1 observed for H2TmCTP under optimal conditions. The best photocatalytic activity observed for H2TCFP was investigated through experiments and density functional theory (DFT) calculations and was interpreted in terms of the combined effect of several key factors of the entire photocatalytic process, including the high absorptivity of UV light, high separation efficiency of photogenerated carriers, and low Gibbs energy required for associated water splitting. Meanwhile, the concentration-dependent performance of photocatalytic activity was analyzed and attributed to the aggregation and light-bleaching effect exerted on porphyrins. [ABSTRACT FROM AUTHOR]

Purifying olefin from ternary paraffin/olefin/alkyne mixtures through a one‐step adsorption process is extremely desirable. Herein, a stable zirconium(IV) metal‐organic framework with a customized pore surface composed of nonpolar phenyl and slightly polar thiophene rings is reported to access the adsorption preference of paraffin and alkyne over olefin. Noteworthily, this material displays a superior ability to discriminate C3 hydrocarbon molecules, which is principally more challenging compared with C2 ones and rarely documented. Computational studies disclose that its featured pore shape fits well with C3 gas molecules, enabling them to get close contact with the immobilized affinity sites. Leveraging surface chemistry and pore shape engineering synergistically gives rise to excellent C3 adsorption capacities (>5 mmol g−1) and concurrently high C3H8/C3H6 (1.4) and C3H4/C3H6 (1.9) selectivities (at 298 K and 1 atm). Dynamic column breakthrough experiments demonstrate that one‐step purification of C2H4 and C3H6 can be simultaneously realized on this material. [ABSTRACT FROM AUTHOR]

Objective To study the effect of vaccination on the short-term risk of immunoglobulin A vasculitis (IgAV) in children. Methods A retrospective analysis was conducted on the general data and the vaccination history within one year prior to onset in children with IgAV hospitalized in the Children's Hospital Affiliated to Zhengzhou University from November 2021 to January 2023. Vaccine exposure rates in the risk period (3 months prior to IgAV onset) and the control period were compared by autocontrol-case crossover analysis, and the odds ratio and 95% confidence interval (95%CI) were calculated. A sensitivity analysis for the one-month and two-month risk periods was conducted. Results A total of 193 children with IgAV were included, with a median age of 7.0 years. Among the 193 children, 36 (18.7%) received at least one dose of the vaccine within 1 year prior to IgAV onset, and 14 (7.3%) received at least one dose of the vaccine during the 3-month risk period. Compared to the unvaccinated IgAV group, the vaccinated IgAV group had a significantly younger age of onset (P<0.05). There were no significant differences in the proportions of children with gastrointestinal involvement, renal involvement, and joint involvement between the two groups (P>0.05). The odds ratio for developing IgAV after receiving any type of vaccine within 3 months prior to IgAV onset was 2.08 (95%CI: 0.82-5.27, P>0.05). Further sensitivity analysis for the 1-month and 2-month risk periods demonstrated that the odds ratios for developing IgAV after receiving any type of vaccine were 2.74 (95%CI: 0.72-10.48, P>0.05) and 2.72 (95%CI: 0.95-7.77, P>0.05), respectively. Conclusions Vaccination dose not increase the risk of IgAV, nor does it exacerbate clinical symptoms in children with IgAV. [ABSTRACT FROM AUTHOR]

With the rapid development of smart health, the privacy problem of medical data has become more prominent. Aiming at the problem of mining the potential value of medical data and realizing secure sharing, a fine‐grained medical data sharing scheme based on federated learning is proposed. The scheme uses collaboration‐oriented attribute‐based encryption technologies to formulate fine‐grained access strategies, allowing medical institutions or doctors to decrypt individually or collaboratively with certain conditions to achieve the purpose of accurately screening the required medical data. In the proposed scheme, the model parameters are shared such that the screened medical data is modeled and analyzed based on federated learning, which allows more people to enjoy top medical resources. In addition, a blockchain‐based incentive mechanism is used to reward medical institutions which are either honest with high‐quality or helpful in decryption. Hence, the enthusiasm of various medical institutions to screen data and participate in federal learning is improved. Finally, security analysis shows that the scheme is secure, and theoretical analysis and simulation test show the practicability of the scheme. [ABSTRACT FROM AUTHOR]

Highly selective photocatalytic conversion of CO2 into valuable hydrocarbon fuel such as CH4 is a promising solution to tackle greenhouse effect and energy shortage. To achieve this goal, more efforts should be made to design well-performed catalysts. In this work, a series of composite photocatalysts were fabricated for CO2 reduction, through hydrothermal mixing of hydroxylated TiO2 (P25m) with sulfonated covalent porphyrin polymers (s-COP-P). Notably, the optimal sample 2%-s-COP-P/P25m (2% denotes the weight percent of s-COP-P) exhibits the highest production rate (15.5 μmol g−1 h−1) and selectivity (> 90%) of all composites for the formation of CH4 within 1 h, which are nearly 33 and 2 times as large as that of P25m. This good performance was attributed to improved photogenerated carrier separation efficiency verified by enhanced photocurrent and reduced fluorescence intensity that associating closely with the interaction between two moieties of the composites. Based on energy band structure analyses and hydroxyl radical probing, the reduction of CO2 into CH4 was proposed occurring mainly on P25m moiety companied with the oxidation of H2O into hydroxyl radical. In addition, high cyclic stability was confirmed for the composite catalyst by constant photocatalytic performance lasting over four times of cyclic test. This work provides a facile and effective way to design stable photocatalyst for the conversion of CO2 into CH4 in high production rate and selectivity. A sulfonated porphyrin polymer/P25m composite of high cyclic stability was fabricated by simple thermal mixing, and exhibits high photocatalytic activity for the conversion of CO2 into CH4 with a rate of 15.6 μmol g−1 h−1 and a selectivity of > 90%. [ABSTRACT FROM AUTHOR]

Three kinds of free base meso‐carboxyphenylporphyrins were compared about their photocatalytic activity to elucidate the role of −COOH group playing in H2 evolution from water splitting. Meso‐tetra(3,5‐dicarboxyphenyl)porphyrin (H2TDCPP) gives a much larger H2 evolution rate than other two porphyrins, attributable to more −COOH groups involved that may interact with H2O. This interaction, as revealed by DFT calculation, initiates H2 evolution from the splitting of associated H2O under ultraviolet light irradiation resulted by effective transfer of photogenerated electron from central porphine ring to meso‐substituents and then further to the interacted water. Improving the accessibility of −COOH groups to water molecule by optimizing H2TDCPP dosage induces an H2 evolution rate around 31.21 mmol ⋅ h−1 ⋅ g−1 (pH=7, full‐spectrum light), which is unprecedented for free based porphyrin photocatalysts without metal‐cocatalysts. This work clarifies the active site role of −COOH groups and paves a new way to design high‐performed organic photocatalysis by introducing polar groups‐based active sites. [ABSTRACT FROM AUTHOR]

Fatty acid synthase (FAS) attracts more and more attention recently as a potential target for metabolic syndrome, such as cancer, obesity, diabetes and cerebrovascular disease. FAS inhibitors are widely existed in plants, consisting of diversiform compounds. These inhibitors exist not only in herbs also in many plant foods, such as teas, allium vegetables and some fruits. These effective components include gallated catechins, theaflavins, flavonoids, condensed and hydrolysable tannins, thioethers, pentacyclic triterpenes, stilbene derivatives, etc, and they target at the different domains of FAS, showing different inhibitory mechanisms. Interestingly, these FAS inhibitor-contained herbs and plant foods and their effective components are commonly related to the prevention of metabolic syndromes including fat-reducing and depression of cancer. From biochemical angle, FAS can control the balance between energy provision and fat production. Some studies have shown that the effects of those effective components in plants on metabolic syndromes are mediated by inhibiting FAS. This suggests that FAS plays a critical role in the regulation of energy metabolism, and the FAS inhibitors from plants have signifi cant potential application value in the treatment and prevention of metabolic syndromes.