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The development of the atmospheric boundary layer is closely connected with the exchange of momentum, heat, and mass near the Earth’s surface, especially for a convective boundary layer (CBL). Besides being modulated by the buoyancy flux near the Earth’s surface, some studies point out that a neutrally stratified residual layer is also crucial for the appearance of a deep CBL. To verify the importance of the residual layer, the CBLs over two deserts in northwest China (Badan Jaran and Taklimakan) were investigated. The summer CBL mean depth over the Taklimakan Desert is shallower than that over the Badan Jaran Desert, even when the sensible heat flux of the former is stronger. Meanwhile, the climatological mean residual layer in the Badan Jaran Desert is much deeper and neutrally stratified in summer. Moreover, we found a significant and negative correlation between the lapse rate of the residual layer and the CBL depth over the Badan Jaran Desert. The different lapse rates of the residual layer in the two regions are partly connected with the advection heating from large-scale atmospheric circulation. The advection heating tends to reduce the temperature difference in the 700 to 500-hPa layer over the Badan Jaran Desert, and it increases the stability in the same atmospheric layer over the Taklimakan Desert. The advection due to climatological mean atmospheric circulation is more effective at modulating the lapse rate of the residual layer than from varied circulation. Also, the interannual variation of planetary boundary layer (PBL) height over two deserts was found to covary with the wave train.

A noncoupled numerical procedure was developed using a scheme of pore water generation that causes shear modulus degradation and shear strength degradation resulting from earthquake cyclic motion. The designed Fast Lagrangian Analysis of Continua (FLAC) model procedure was tested using the liquefaction-induced lateral spread and ground response for Wildlife and Kobe sites. Sixteen well-documented case histories of lateral spread were reviewed and modeled using the modeling procedure. The dynamic residual strength ratios were back-calculated by matching the predicted displacement with the measured lateral spread, or with the displacement predicted by the Yound et al. model. Statistical analysis on the modeling results and soil properties show that most significant parameters governing the residual strength of the liquefied soil are the SPT blow count, fine content and soil particle size of the lateral spread layer. A regression equation was developed to express the residual strength values with these soil properties. Overall, this research demonstrated that a calibrated numerical model can predict the first order effectiveness of liquefaction-induced lateral spread using relatively simple parameters obtained from routine geotechnical investigation. In addition, the model can be used to plan a soil improvement program for cases where liquefaction remediation is needed. This allows the model to be used for design purposes at bridge approaches structured on liquefiable materials.

In this study, genetic parameters were obtained for growth and cold tolerance of 99 Fenneropenaeus chinensis juvenile families by means of indoor artificial cooling (starting from 14°C, 2°C/d). A linear mixed model was fitted to estimate variance components using the ASReml software package. Heritabilities estimated for body weight (BW) and body length (BL) of F. chinensis juveniles were 0.078 ± 0.124 and 0.131 ± 0.133, respectively. The estimates of heritability were low in magnitude for both traits. The differences between the heritabilities estimated for the two growth traits were not significant with each other, and the heritabilities were not significantly different from zero (P > 0.05). The phenotypic and genetic correlation coefficients between BW and BL were as high as 0.9408 ± 0.0040 and 0.9562 ± 0.0551, respectively, and both were significantly different from zero (P < 0.01). The heritabilities of temperature at death (TAD) and cooling degree hours (CDH) were 0.265 ± 0.091 and 0.077 ± 0.058, respectively. The heritability estimates for TAD was moderate and significantly different from zero (P < 0.01). The correlation analysis indicated that the phenotypic correlation coefficient between TAD and CDH was -0.5470 ± 0.0174, and the genetic correlation coefficient was -0.6707 ± 0.3635. In the analysis of growth traits and cold tolerance traits, the values of phenotypic correlation coefficient were floating between -0.1055 and 0.1098, both were significantly different from zero (P < 0.05), while the genetic correlation had a larger range (0.0526 ~ 0.9914), and all were not significantly different from zero (P > 0.05). In this study, there was a low correlation between growth and cold tolerance traits, indicating that growth traits and cold tolerance traits should be considered collectively in the breeding program of shrimp.

Shuohuang Railway (SHR) is one of the major coal carriers in China, with a total network length of 590 km running from Shenchi to Huanghua. Significant increases in annual operating tonnage have generated accelerated rail wear and rolling contact fatigue (RCF) growth problems for many sharper/lower radius curves. In order to address these rail problems, SHR is interested in the state-of-the-art total friction management (TFM) technology currently deployed by some North American heavy haul freight railroads and is evaluating the impact of TFM via a field trial at SHR’s Yuanping subdivision. This paper presents an evaluation of the effect of TFM, which includes both wayside gauge face lubrication and wayside application of a thin film top of rail friction modifier on control of lateral forces, rail wear and RCF.

On the basis of solid mechanics,the "Peeling off " problem of TPS tiles on space craft surface is investigated.After considering the existence of peeling stress along the interface between the TPS tiles and the frame of space shuttle,a new model of mechanics is established to satisfy the boundary conditions of shear stress,which cannot be satisfied by the traditional shear-lag model.According to these new solutions,the reasonable explanation can be made about the failure of glued joint for TPS tiles.The stress distributions are studied when TPS tiles working in high temperature condition have different length,thickness,and material,and some advices can be provided to the design of TPS tiles.

White spot syndrome virus(WSSV)is one kind of destructive virus affecting shrimp industry in the world.Output of Fenneropenaeus chinensis which once was a staple species has been greatly affected by outbreak of WSSV since 1993 in China.To produce WSSV-resistance shrimp strains is an important approach to revive the shrimp industry.To select survived F.chinensis as broodstock via WSSV challenge test can increase the efficiency of breeding.However,mortality of shrimps could reach nearly 100% once they were infected with WSSV,which increases the difficulty for shrimp breeding.In this study for the purpose to reveal effect of different WSSV amount on F.chinensis,juvenile F.chinensis were infected with a certain amount of WSSV individually and the survival time and survival rate were observed.The results showed that survival time of shrimps infected with 5.2×108 copies,1.0×109 copies and 2.1×109 copies of WSSV respectively was 389.3,323.3 and 187.3 h and significant different(P0.01).The cumulative mortalities of all the shrimps finally reached 100%.The survival time increased while shrimps were fed with less WSSV bait.For the purpose to reveal the effect of diets on the ability for disease resistance,shrimps infected with WSSV were fed with different diets of live brine shrimps,commercial bait and fresh clam.It was showed that the survival time of infected shrimps fed with live brine shrimps,fresh clam and commercial bait respectively was 281.7,173.9 and 164.9 h.The survival time of infected shrimp fed with live brine shrimps was significantly higher than that fed by commercial bait and fresh clam respectively(P0.01).There was no significant difference of survival time between infected shrimps fed with commercial bait and fresh clam(P0.05).Cumulative mortalities of all the groups of infected shrimps that fed with different diets were 100%.Live brine shrimp is better than commercial bait and fresh clam for the purpose of enhancing shrimp WSSV resistance ability.