Filtrate reducer is facing higher requirements and challenges in temperature and salt resistance. A novel polymer filtrate reducer was synthesized by free radical polymerization in aqueous solution. By filtration experiments, the results show that the polymer has good filtration loss performance under high temperature and saturated salt. Through the optimization with filtrate reducer and inhibitor, the optimum components of drilling fluids are water, 4.0wt% bentonite, 0.3wt% Na 2 CO 3 , 2.0wt% DAADS, 3.0wt% SMP-II, 3.0wt% SPNH, 3.0wt% SMC, 1.0wt% SDJA and 2.0wt% RH-3. The drilling fluid system has temperature resistance up to 220°C, salt resistance to saturation and calcium resistance up to 1.0%. The API fluid loss of the drilling fluids with the addition of saturated NaCl and 1wt% CaCl 2 respectively after aging at 220°C was 6.0 mL and 4.4 mL.

Sichuan Basin is one of the centers of pummelo cultivation, domestication and diversity. Also, as one of the main production areas, Sichuan Basin possessed abundant pummelo germplasm resources. In this study, genetic diversity analysis among 73 accessions of pummelo ( Citrus grandis Osbeck) and rootstocks from Sichuan Basin was assessed by using RAPD markers. A total of 156 bands were amplified by 15 RAPD primers, 93.59% (146) of which 146 were polymorphic with an average of 10.4 polymorphic bands per primer. The genetic similarity coefficients of 73 germplasms varied from 0.4511 to 0.9808 at the accession level. At the group level, the maximum GS coefficient index was observed between Wendan and Guanxi Miyou & bud mutants (0.8838), and the minimum GS coefficient was shown in Shatianyou and Putaoyou (0.6852). 73 accessions of pummelo and rootstocks were clustered into five groups with UPGMA method at distance coefficient of 0.6102, consisting of Shatian pummelo varieties group, Wendan pummelo varieties group, Guanxi Miyou & bud mutants group, Putao pummelo varieties group, and rootstocks of C. junos (Pujiang Xiangcheng and Ziyang Xiangcheng) and Poncirus trifoliata . In addition, Guanxi Miyou and bud mutants were clearly separated in our RAPD analysis. This study demonstrated abundant genetic variation among Guanxi Miyou and bud mutants, which could be used core germplasms in the future pummelo breeding program.

Plastic film mulching (PFM) around fruit trees could effectively improve fruit quality by promoting fruit coloration and sugar accumulation. 'Hongroumiyou' and 'Sanhongmiyou' are mutated from Citrus grandis cv. 'Guanximiyou' possessing attractive appearance, rich nutritional ingredients. When they are introduced into Sichuan Province, the fruits revealed lower sugar accumulation and higher acid content than that in Fujian Province. We compared the fruit quality by mulching at 55, 85, 115, 145, 175 days after flowering. The results showed that mulch treatment had no significant effect on the external quality of 'Hongroumiyou' and 'Sanhongmiyou'. While it could effectively improve the internal fruit quality, including promotion of total soluble solid and vitamin C, and decrease of total acid. The best effect on the improvement of fruit quality was mulched at 115 days after flowering for 'Hongroumiyou' and 145 days after flowering for 'Sanhongmiyou'. In addition, mulching cultivation also avoided tree death resulted from the rootrot atrophy because of a long-term flooding. It is important to promote film mulching cultivation in the pummelo production in Sichuan Province.

Power dispatching network is a core of cardinal significance, which always suffers from the network attacks from both inside and outside of the local-area network. The network attack detection process must perform tremendously good, or will disturb the normal business traffic. This paper proposed an automatous method to inspect the net traffic and identify the abnormal traffic only by analyzing several signals rather than probing the network traffic packet.

Once an explosion occurs, it would threaten the safety of personnel and facilities around the launch site. In order to study the propagation law of shock wave near-ground and the multiplicative effect on peak overpressure of the ground, the finite model of near-surface explosion has been established based on explicit nonlinear dynamic ANSYS/LS-DYNA program. Results show that the existence of the ground will change the propagation law and conform to the reflection law of the shock wave. For gauges at different heights, ground may have different effects on the peak overpressure. When x is not greater than 20m, the peak overpressures of h greater than 2m are the same, but less than the peak overpressures of h equal to 2m. When x is greater than 20m, the peak overpressure decreases with the increase of h, and eventually the peak overpressure of different h gradually tends to be the same.

Taking the main bridge of the shuidong bridge in Youxi country of Fujian province as background, this paper develops the static characteristic analysis and static load test study on long-span prestressed continuous rigid frame bridge with V-shaped pier. By the analysis and comparison between the measured data and FEA results, it evaluates the working condition of the bridge. The results show: Firstly,each evaluation indicator tested meets the requirements of "Test methods for large-span concrete bridges" Secondly, the strain efficacy coefficient of measured points in top plate of each control section is within 0.65∼0.74, and that of the measured points in bottom plate is within 0.64∼0.73, the residual strain of the measured points is less, therefore, the safety stock of the bridge is sufficient, and it is on the flexible working condition basically; Finally, the measured value and the theoretical value of deflection curves along the longitudinal bridge is compatible, the efficacy coefficient of vertical deformation is within 0.55∼0.85, and the severity of the practical structure is more.