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In view of the imperfection of the pipe-jacking pipeline corrosion parameter detection device and testing system，a set of flexible surrounding pipeline detection device was designed.With the support of ground test pile，this device could measure relevant potential and current easily，meeting the data requirements of corrosion risk assessment.Finally，the resistivity calculation of the anti-corrosion layer based on the current potential method，the judgment of the damage point of the anti-corrosion layer based on the close interval potential (CIPS)，the diagnosis of the sacrificial anode performance based on the current trend，and the prediction of the corrosion rate based on the current density of the test piece were established.Furthermore，the single risk assessment methods regarding the electrical resistivity of the anti-corrosion layer，the damage point，the sacrificial anode performance，the cathodic protection effect and the corrosion rate were formulated.The comprehensive evaluation system of corrosion risk of the local monitoring points and the whole pipe section was established，which would have great guiding significance for the preventive management of the pipeline.

To clarify the interference situation, interference law and corrosion law of different pressure level system of mega-city gas pipeline network under the influence of different railroad lines, 37 test piles of nearly 10 pipelines crossing or parallel with electrified railroad were selected for a 24-hour data monitoring and analysis, and the interference law and risk situation of Beijing area under dynamic AC stray currents were identified. Results showed that sub-high voltage and above gas pipeline networks were significantly more affected by the interference of electrified railroad than medium and low voltage pipeline network in Beijing area;the sacrificial anode cathodic protection system of city gas pipeline network had a certain degree of drainage mitigation and anti-interference function for stray current interference;the AC interference on pipelines parallel with electrified railroad was greater than that on crossing pipelines, and the peak was related to locomotive location. For the corrosion risk under dynamic AC interference, it was recommended to evaluate it by combining the proportion of AC current density range with outage potential.

In China, the sacrificial anode cathodic protection systems of many pipelines in service with asphalt coating have failed or are about to fail. If the sacrificial anode systems are replaced according to the original design, some pipelines could not be effectively protected. In this work, based on the surface resistivity change rule of the anticorrosive layer of on - site pipeline with time, the change of resistivity of the as - mentioned anticorrosive layer in the next 20 years was predicted. The change of protection distance of pipeline after 15 years of operation with time was estimated using simulation calculation, which provided a basis for the redesign of cathodic protection system. Results showed that the surface resistivity of anticorrosive layer of asphalt coating decreased with the prolonging of burried time, and the decreasing rate decreased gradually; the damage rate of anticorrosion coating increased with the prolonging of buried time, and the increase rate rised gradually. After 15 years of operation single group sacrificial anode protection system, the single - side protection distance of the pipeline was 50 m. And then with the continuous service of the pipeline, the single - side protection distance decreased significantly. After 20, 25, 30 and 35 years of operation, the single - side protection distance declined to 28.0, 19.0, 14.0 and 11.5 m, respectively. When the distance between the anode and the pipeline was in the range of 1～4 m, with the increase of such distance, the potential distribution on the pipeline became more and more uniform, and the protection distance increased. Furthermore, in the next 20～35 years, the replacement time of sacrificial anode system would have little impact on the anode life, which was estimated to be about 23 years.

Henosepilachna vigintioctomaculata is distributed in several Asian countries. The larvae and adults often cause substantial economic losses to Solanaceae crops such as potato, tomato, eggplant, and Chinese boxthorn. Even though a chromosome-level genome has been documented, the expression profiles of genes involved in development are not determined. In this study, we constructed embryonic, larval, pupal, and adult transcriptomes, generated a comprehensive RNA-sequencing dataset including ~52 Gb of clean data, and identified 602,773,686 cleaned reads and 33,269 unigenes. A total of 18,192 unigenes were successfully annotated against NCBI nonredundant protein sequences, Swissprot, Eukaryotic Orthologous Groups, Gene Ontology (GO), or Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. There were 3580, 2040, 5160, 2496, 3008, and 3895 differentially expressed genes (DEGs) between adult/egg, egg/larval, larval/pupal, adult/pupal, egg/pupal, and adult/larval samples, respectively. GO and KEGG analyses of the DEGs highlighted several critical pathways associated with specific developing stages. This is the first comprehensive transcriptomic dataset encompassing all developmental stages in H. vigintioctomaculata. Our data may facilitate the exploitation of gene targets for pest control and can serve as a valuable gene resource for future molecular investigations. [ABSTRACT FROM AUTHOR]

To better understand the mechanical property issues of in-service concrete-filled steel tube (CFST) bridges susceptible to natural environmental temperatures, 13 CFST stub columns were assessed under axial compression with different ambient temperatures and steel ratios, with the strength of the core concrete as the main parameters. The influence of ambient temperature on the peak strain and joint elastic modulus of the CFST stubs was investigated. The influence mechanism of steel content and core concrete strength on the residual toughness of the CFST at different ambient temperatures was revealed. In this study, we proposed a modified constitutive equation for CFST, taking into account the ambient temperature. We demonstrated that the peak strain, residual toughness ratio, and elastic modulus of the CFST stubs significantly decreased when the temperature decreased. The calculated values of the modified constitutive equation for CFST, taking into account the ambient temperature, were in good agreement with the test results and could be used to predict the trends in stress properties of the CFST stubs at different temperatures. The results could serve as a critical reference for the design and calculation of CFST structures in very cold regions. [ABSTRACT FROM AUTHOR]

Here we report a light‐induced FeCl3‐catalyzed approach for benzyl C−H chlorination with remarkable regioselectivity, which enables alkylbenzenes to be converted into versatile benzyl chlorides under mild conditions using trifluoromethanesulfonyl chloride (TfCl) as the chlorine source. DFT calculations show that the dynamics preference of benzylic α−C−H chlorination is more pronounced by employing TfCl. [ABSTRACT FROM AUTHOR]

The species of Ramaria are coralloid-fungi with intricately branched and vividly coloured basidiomata. There are many studies on the genus Ramaria in China, but molecular phylogenetic analysis is rarely employed. In this study, we performed a multigene phylogenetic analysis to identify Ramaria species in Shanxi Province of northern China. Phylogenetic analyses based on four loci, the internal transcribed spacer region of nuclear ribosomal DNA (ITS), the nuclear large subunit ribosomal DNA (nrLSU), ATPase subunit 6 (atp6), and mitochondrial small subunit ribosomal DNA (mtSSU), revealed 13 Ramaria species from our collections. Combined with morphological examinations, 12 of them were identified as new species, plus a new report to China. The thirteen species were described and illustrated in this paper. [ABSTRACT FROM AUTHOR]

NADPH -cytochrome P450 reductase (CPR) is the most important redox partner of various cytochrome P450 monooxygenases (P450s) and plays a central role in multiple metabolic reactions. In this paper, a full-length cDNA encoding CPR (designated as CmCPR) was characterized in the rice leaffolder, Cnaphalocrocis medinalis (Guenée), a serious lepidopteran rice pest. The complete open reading frame of CmCPR was 2046 bp, encoding a protein consists of 681 amino acid residues. The secondary structure of CmCPR protein showed marked features of classical CPRs such as N-terminal anchor, conserved functional domains, and catalytic residues. Phylogenic analysis showed that CmCPR was clustered together with CPRs from other lepidopteran species. Recombinant CmCPR protein was expressed in E. coli, and the activity and kinetic parameters of the enzyme were determined. Quantitative reverse transcription-PCR showed that the highest expression levels of CmCPR were detected in fourth- and fifth-instar larvae, and the transcriptional level in larval midgut tended to be higher than those in other tissues. Exposure to sublethal concentrations of three insecticides, abamectin, chlorpyrifos, and chlorantraniliprole, led to upregulated expression of CmCPR and several P450 genes. This work is the first report of molecular characterization of CPR gene in Cn. medinalis. [ABSTRACT FROM AUTHOR]