In order to solve the problem of imbalance development in the maintenance of new types of rural roads,based on the technical condition of rural road pavements,the rate of good pavements based on the pavement technical condition index is selected as the evaluation index of the level of technical condition of pavements,and 1,607 counties(cities,districts and banners)in non-policy-supported areas of 2,717 county-level administrative units with rural road management and maintenance tasks nationwide are taken as samples to analyze the technical condition of the pavements in the rural road pavements in the regions which are not supported by the policy.The technical condition of rural road pavements in regions that have not received policy support is analyzed.The results of the study show that the overall technical condition of pavements in non-policy-supporting regions is higher than the average level of the whole country and policy-supporting regions.The 30 non-policy-supported counties(cities and districts)in the Eastern region,109 non-policy-supported counties(cities and districts)in the Central region,and 108 non-policy-supported counties(cities,districts and banners)in the Western region are lower than the average level in the Western region.The problem of backwardness of pavement technical condition occurs in non-policy support areas.It is recommended that the non-policy-supported counties(cities,districts and banners)with low rates of good roads and backward pavement technology should conduct field research on the technical condition of their rural road pavements,and adjust the strength of their policy support.
This paper points out that the traction power supply system of high-speed railway is a special power system composed of traction substations, traction network and electric locomotives. In order to study the traction power supply system of high-speed railway, this paper selects the appropriate modules in the alternative transients program –electromagnetic transient program（ATP-EMTP） to build the simulation models of each component of the traction power supply system, and verifies the accuracy of the model through the simulation experiment, providing a certain reference basis for the design, repair and maintenance of high-speed railway.
In this study,the third generation sequencing is used to sequencing of the full length transcriptome library and obtain the FGF gene sequence.PCR primer is design according the sequence.The PCR product is directly sequenced to verify the gene sequence,and the full length of the FGF gene is 787 bp.The ORF length of the FGF gene is 699 bp,encoding a total of 232 amino acids.The results of nucleic acid sequence homology analysis shows that it shares 99.50%homology with Cyplinus carpio FGF13 gene,and has high homology and close genetic relationships with the corresponding FGF genes of Sinocyclochei-lus grahami,Cyprinus carpio,Cara-ssius auratus,and Danio rerio;further comparison revealed 99.01%homology with the amino acid sequence of the FGF13a-2 gene,indicating that the gene is the FGF13a-2 gene of Schizothorax grahami.The structural domain prediction includes receptor binding sites and heparin binding sites,and the FGF gene encodes proteins in the secondary structure,the proportion of α-spiral is 22.41%,the proportion of β-corners is 8.19%,the proportion of extended chains is 21.55%,and the proportion of random curls is 47.84%,having the characteristics of FGF protein transcription factor superfamily.
The"dual mentor system"project in Shaanxi Province is a new mechanism established by the Shaanxi Provincial Department of Science and Technology in basic research technology projects.This paper reviews the domestic and foreign literature on the performance evaluation of the"dual mentor system"project in Shaanxi Province,especially basic research projects,with a focus on elaborating on the research process and evaluation methods.The analysis found that the specific research on the performance evaluation methods of the"dual mentor system"project in the field of basic research is still relatively weak,and the evaluation methods are not diversified enough;in terms of the design and application of performance evaluation indicators,there is a majority of theoretical exploration,and there is less practice in combining basic research with sci-tech project cases.This will be a direction for future research.
In view of the difficulties in construction,high requirements for stability and durability of super-large bridges and cross-embankment bridges,and based on the hydrogeological characteristics of the Yellow River super-large cross-embankment bridge on Puyang-Yangxin Expressway,two schemes of prestressed concrete continuous beams and prestressed concrete composite beams with corrugated steel webs are designed.The comparative analysis on the maintenance amount in the later period shows that the combination of concrete and steel materials in the prestressed concrete beam bridge with corrugated steel webs can significantly reduce the risk of web cracking and midspan deflection of long-span concrete beam bridges,reduce the dead weight of the bridge by 15%,reduce the seismic force,reduce the cost and shorten the construction period.However,the construction technology is complex,the requirements for construction control and quality are very high,the later maintenance is difficult,the maintenance cost is high,and the construction technology is not mature.The gap between the two design schemes mainly lies in the structural rationality,construction period and project cost,construction difficulty,and later maintenance.After comprehensive consideration of relevant factors,the prestressed concrete continuous beam design scheme should be selected for the Yellow River super-large cross-embankment bridge on Puyang-Yangxin Expressway.However,it is necessary to deal with the midspan downwarping and structural anti-seismic problems.At the beam end and tower end,traction tensioning equipment to eliminate cracks,twist or limit twist should be used to improve the construction quality and safety of stay cables.
