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The forced sweat cooling of porous media is an effective way to solve the problem of thermal protection of the leading edge of hypersonic vehicles. The pore structure and performance of porous media have a significant impact on its cooling effect and reliability. Therefore，it is very important to prepare porous materials that meet the requirements of forced sweat cooling. Herein，Ti6Al4V pre-alloyed powders were used as raw materials，and porous Ti6Al4V samples with different open porosity were prepared by compression molding combined with high-temperature sintering. The effect of the sintering temperature and holding time on the microstructures，phase compositions and mechanical properties of the samples were investigated. The results show that increasing the sintering temperature and prolonging the holding time will reduce the open porosity of the material. When the open porosity is high，the pores in the material are connected and the seepage rate is high，while the sample strength is low. When the open porosity is low，large pores in the sample are reduced and the seepage rate decreases，but the strength becomes higher. The porous Ti6Al4V sample with an open porosity of 21.8% shows the best comprehensive performance. When the porous Ti6Al4V sample is used as active thermal protection material，it can withstand flame ablation with an average heat flux of 2.5 MW/m2.

Hollow structured carbon nanofibers (HCNFs) are one of porous carbon nanofiber materials. They exhibit high specific surface areas, developed pore structure, and more active sites. They are widely used in energy storage devices, filtration and adsorption materials, catalyst carriers, and other emerging fields. In this paper, the development of HCNFs were reviewed. The preparation methods of HCNFs were briefly introduced, including uniaxial electrospinning and coaxial electrospinning. The recombination and doping of HCNFs were mainly introduced. Changing or improving the performances of HCNFs can expand the application fields of HCNFs. In addition, the application prospects of HCNFs in the fields of the lithium-ion battery, catalysis, supercapacitor, and adsorption were emphatically introduced. The development direction of HCNFs in the future is prospected to provide a reference for the research and development of HCNFs. [ABSTRACT FROM AUTHOR]

The lime-neutralized phosphogypsum was surface-modified with potassium methylsilicate, and mixed with cement, machine-made sand and chemical admixtures to make wet-mixed mortar. The hydration and hardening of the modified phosphogypsum cement-based mortar was analyzed by XRD and SEM. The mineral composition and microscopic morphology of the mortar were investigated,and the effect of potassium methylsilicate modified phosphogypsum on the mechanical properties of mortar was investigated. Results show that potassium methylsilicate adhered to phosphogypsum crystal surface and partially blocked the dissolution of phosphogypsum particles by water molecules. Compared with that without the addition of potassium methylsilicate, the saturated concentration of SO42- ions in the modified phosphogypsum with the content of 0.4% and 0.6% potassium methylsilicate decreased by 40% and 42%, respectively. The retarding effect of modified phosphogypsum on hydration reaction of C3A in cement is weakened, the setting time of mortars is shortened,and the consistency of mortars is increased gradually. When modified phosphogypsum with 0.4% and 0.6% potassium methylsilicate, the compressive strength of mortar is 11.4MPa and 11.9MPa after 28 days, which can meet the WP M10 strength requirements of the industrial standard JC/T230--2007 "Pre-mixed mortar". [ABSTRACT FROM AUTHOR]

Ramping-up is the magnet current injection procedure which is under the control of resistance, voltage, current lead temperature, magnet pressure, temperature and so on. In this procedure, the factors related to the stability of the magnet such as, magnet temperature, pressure and currents are constantly changing. This procedure is the main step which the magnet-quench occurs in. This study uses the data collected during 7 years and SIMENS MRI ramping-up theory, in order to help engineers understand the key factors to reduce the magnet quench during the ramping up procedure.

The modifications of slices, flip angle, SAR mode and TR time are required when the SAR exceeds the limits. The scan time and image quality are affected by those. This study analyzes the SAR from the basic side. With the principle diagram of SIEMENS 1.5 T AVANTO and 3.0 T VERIO MRIS, the trouble shooting procedure of SAR problem is reached both in application and problem sides.

Objective To investigate the effect of interleukin 27 (IL-27) on hepatitis B virus (HBV) replication and antigen secretion in HepG2.2.15 cells and related mechanisms. Methods HepG2.2.15 cells were treated with IL-27 at various doses. The levels of HBsAg and HBeAg in the supernatant of the cell cultures were measured by ELISA, and the levels of HBV DNA was detected by real-time quantitative PCR. The expression and localization of HBV core antigen (HBcAg) in HepG2.2.15 cells were observed by immunocytochemical staining. Moreover, the expression of STAT1, phosphorylated STAT1 (p-STAT1) and myxovirus-resistance protein A (MxA) were analyzed by Western blotting. Results After the treatment with different doses of IL-27, the levels of HBV-DNA, HBsAg, HBeAg and intracellular HBcAg in HepG2.2.15 cells gradually decreased. With the increase of IL-27 dose, the expression level of p-STAT1 significantly increased. There was no significant change in STAT1 expression. Further studies also showed that IL-27 induced MxA expression in a dose- and time-dependent manner in HepG2.2.15 cells. Conclusion IL-27 could induces MxA expression by activating STAT signaling pathway to exert anti-HBV activity.

Objective: To establish a method for determination of geniposide in Beagle dogs plasma by high performance liquid chromatography (HPLC), and study the pharmacokinetics and bioavailability of geniposide in Beagle dogs after oral administration Xingnaojing., Method: To determine the geniposide in Beagle dogs plasma by HPLC after oral administration or intravenous injection Xingnaojing, and the pharmacokinetic parameters were calculated by the software of Kinetica., Result: The good linearity range of geniposide was 1.24 - 158.88 mg x L(-1). The main pharmacokinetic parameters after oral administration was as follows: Cmax (11.8 +/- 0.6) mg x L(-1), Tmax (52.0 +/- 4.5) min, AUC(1280.8 +/- 172.0) mg x min x L(-1), MRT(118.7 +/- 25.4) min, and these parameters after intravenous injection was follows: Cmax 107.4 +/- 6.3) mg x L(-1), AUC(7930.1 +/- 670.0) mg x min x L(-1), MRT(92.4 +/- 5.1) min. The bioavailability of geniposide in Beagle dogs after oral administration Xingnaojing was (6.46 +/- 0.87)%., Conclusion: The HPLC method had good applicability. The extract recovery, method recovery, intra-day precision and inter-day precision of the method were all met the requirements. The stability in conditions of room temperature and freeze-thaw cycle was good. The results indicated that the oral administration bioavailability of geniposide was in low degree.

Objective: To analysis the volatile components of Trogopterus faeces., Method: The volatile components of Trogopterus faeces was extracted by steam distillation and analyzed by GC-MS., Result: Eighty-five volatile components were identified and the main components are cedrol (12.31%) and caryophyllene (7.5%)., Conclusion: The volatile components of the samples are originated from the ingredients or other chemical compositions with similar basic structure of the fodders.

Objective: To study the processing technics of prepared slice of Rhizoma Dioscoreae for its industrial production., Method: The effect factors, such as stiring temperature (60, 80, 100 degrees C), stiring time (10, 20, 30 min) and the proportion of pieces and wheat bran (100: 5, 100: 10, 100: 15) were evaluated by orthogonal method. The content of allantoin in Rhizoma Dioscoreae was determine by HPLC method., Result: The amount of wheat bran could affect the content of allation significantly, and stiring temperature and stiring time almost had no effect on content of allantoin. The processing technics was tested by industrial produce, according to 11 batches from 4 growing regions. The result showed that the quality of industrial product was stable., Conclusion: That the amount of wheat bran can affect the quality of Rhizoma Dioscoreae greatly. The determined technics is simple and suitable for prepared slice of Rhizoma Dioscoreae industrival manufacture.

In this paper, the references between Genetic Soil Classification of China (GSCC) and the Chinese Soil Taxonomy (CST) for GSCC-Semi-Luvisols were conducted, and their quantitative and spatial distribution characteristics within CST were studied, based on the 1 : 1 M Soil Database of China, which consists of 1 : 1 M digital soil map, soils profiles attribution database and soil reference system of China. Being a reference system for converting soil names in GSCC into those in CST, ST and WRB, respectively, Chinese Soil Reference System was a computerized retrieving system jointly developed by the experienced scientists of pedology and computer science. The comparison fields and laboratory investigation data of their soil profiles with diagnostic horizons and characteristics related in the target soil classification systems, and 2,540 typical soil species names corresponding in CST, ST and WRB systems were determined, respectively, which were selected from Soil Attributes Database because of their complete sets of attribute data. Finally, the system and reference database were established. "GIS linkage based soil type" method linked the records in the Soil Reference Database to the Soil Spatial Database. In this method, all records of soil profiles in Soil Reference Database as well as their soil reference name in other classification systems were allocated one by one onto corresponding soil type polygons in Soil Spatial Database on the GIS platform, according to the principles of soil type identity and similarity, parent material identity and likeness, and the location of soil profiles relative to linked target polygons. Area statistcs of all soils were conducted based on the polygons. The results showed that GSCC-Semi-Luvisols was a type of GSCC soil with a total area of 427,843.1 km2,which could be sorted to 4 CST Orders, i. e., Luvisols (51.3%), Cambosols (35.2%), Isohumosols (10.7%) and Anthrosols (2.8%), and further into CST 22 Groups and 38 Subgroups. All dark grey forest soil, superficial gleyed black soil, and leached dry red soil of GSCC subgroups could be sorted to Calcaric Hapli-Gelic Cambosols, Pachic Argi-Udic Cambosols and Typic Ferri-Ustic Luvisols of CST subgroups, respectively, and all grey cinnamon-like soil, calcareous grey cinnamonic soil and dry cinnamon soil could be sorted to Typic Ustic Cambosols. Making the reference was so complicated that there was no one to one reference relationship among other soils. The analysis of the area ratios and standard deviations of a certain GSCC soil classified by CST showed that the lower the unit for reference, the easier the reference would be. The results of this study were of high reference value to proper reference GSCC and CST, and to the application and development of CST.

Based on 1:1,000,000 soil database, and employing the methods of spatial expression, this paper estimated the soil organic carbon storage (SOCS) and density (SOCD) of China. The database consists of 1:1,000,000 digital soil map, soil profile attribution database, and soil reference system. The digital soil map contained 926 soil mapping units, 690 soil families, and 94 000 or more polygons, while the soil profile attribution database collected 7292 soil profiles, including 81 attribution fields. The SOCDs of soil profiles were calculated and linked to the soil polygons in the digital soil map by the method of "GIS linkage based on soil type", resulting in a vector map of 1:1,000,000 China SOCD. The SOCS of the country or of a soil could be estimated by summing up the SOCS of all polygons or the polygons of a soil, and their SOCD were the SOCS of them derived by their areas. The estimated SOCS and SOCD of the country was 89. 14 Pg (1 Pg = 10(15) g) and 9.60 kg m(-2), respectively, covered all the soils with a total area of 928.10 x 10(4) km2, which might be considered closest to the real value.