猪繁殖与呼吸综合征病毒S1株单克隆抗体的制备及生物学特性研究

通过差速离心和蔗糖密度梯度了心法对猪繁殖与呼吸综合征病毒沪1（PRRSV－S1）株进行抗原纯化。免疫BAIB／c小鼠，取脾细胞与SP2／O融合，用间接ELISA和有限稀释法,获得2株稳定分泌抗PRRSV单抗的杂交瘤细胞株，分别命名为AG、BD3。ELISA交叉试验和阻断试验表明，2株单抗具有高度特异性。AG1可与PRRSV－S1，欧洲株LV，美洲株VR－2332反应，而BD3与美洲株VR－2332反尖较弱，2株单抗对猪细小病毒（PPV）、猪伪狂犬病病毒（PRV）、猪乙型脑炎病毒（JEV）均不反应。阳性杂交瘤细胞的上清液效价是：1：256－1：5123，腹水效价分别在1：10^3－1：10^5之间。AG1和BD3各有100条染色体，琼脂双扩散试验结果表明AG1属于IgG2b，BD2属于IgM。Western blot试验表明AG1和BD3是针对N蛋白抗原表位的特异性单抗。     

犬用复合麻醉剂QFM合剂对犬循、环呼吸系统功能影响的研究

QFM合剂是一种新型的犬用复合麻醉制剂。为了验证其对犬生理功能的影响，本试验通过用QFM合剂以0.15-0.2mL/kg体重剂量对7条犬进行麻醉，用Detax循环监护仪、De-tax呼吸监护仪和SJ-42型生理多道记录仪对麻醉前后犬的循环、呼吸系统功能进行监测。结果证明：QFM麻醉合剂对机体的循环、呼吸系统功能影响轻微。     

Numerical Simulation of Elastoplastic Multi-scales Model for Magnesium Alloy Under Tensile Load

In order to investigate the macroscopical mechanical performance of magnesium alloy material containing pore and the mechanism during distorting destructing, an accurate finite element model of magnesium alloy using the multiscales method was developed, and the macroscopic properties of material under the macroscopic tensile load using the developed constitutive model of multi-scales and finite element method was obtained. By analyzing the distortion results of meso-model through the multi-scales method, with macroscopical load increasing, the difference demonstrated on the macroscopic is very small, however, with the increase of the load step, the phenomenon that the ability of plasticity deformation of the meso-models which includes the cuboid pore decreased gradually remarkable and the phenomenon of stress centralized is more severity than the meso-models including cylindrical pore could be obviously observed during the process of deformation on the meso-models.     

Influence of Macromolecule-type Retarders on the Hydration and Microstructure of Hardened Paste

Influence of one macromolecule-type retarder bone glue on the setting time, strength, ion concentration in liquid phase and supersaturation degree, crystal morphology of dehydrate and microstructure of hardened paste of building gypsum is investigated. Furthermore, internal cause of strength loss of building gypsum with addition of retarder is analyzed, The results indicate that bone glue could retard the hydration of building gypsum markedly, but its negative influence on the strength of building gypsum is far lower than that of low molecule-type retarders. Bone glue has a minor effect on crystal morphology of dehydrate and porosity of hardened paste, but it causes the large crystal size and coarsening of pore size distribution of hardened gypsum paste, which is the very intrinsic reason of strength loss of building gypsum.     

The Ultrafine Physical Structure Characteristics of Coal

The amorphous structure characteristics of coal and their variation regularity are discussed.The pore structure features and models of coal have been reviewed in detail.     

Prognosis of Methane Formation by River Sediments (9 pp)

Background   Under anoxic conditions typically prevailing in disposal sites for dredged sediment, methanogenesis is the terminal step during microbial degradation of sediment organic matter. Sediment gas production may pose several problems to site management and post-closure utilisation. Depending on the magnitude of gas/methane formation and the intended utilisation of the site, countermeasures will have to be effected during and after deposition of the dredged material. For this purpose it may be of interest to pre-estimate the extent of gas formation from simple sediment variables. Therefore, the aim of the investigations presented here was to analyse the interrelations between gas formation and sediment physical, chemical and biological qualities. Methods   Freshly sampled riverbed sediment from nine German federal waterways was analysed for standard solid physical and chemical parameters, pore water composition, cell counts of methanogenic and sulfate-reducing bacteria, and gas formation over a period of 500 days. Particle size and density fractionation were carried out in order to characterise organic matter quality. Correlations between methane formation and sediment chemical, physical and microbiological characteristics were tested using linear and multiple correlation analysis. Results and Discussion   The selected sediments, including two with marine influence, differed strongly regarding texture, chemical parameters, pore water composition, and methanogen cell counts. The course of methane formation was found to follow distinct phases. The commencement of methane formation was preceded by a lag phase of variable duration. The lag phase was followed by a strong increase of the methane formation rate up to a sediment-characteristic maximum of 5–30 nmol CH4 h–1 g dw–1. Eventually, the rate of methane formation decreased and reached a more stable, long-term level. The extent and amplitude of each phase varied strongly between sediments and could be correlated well with only a few standard analytical parameters, despite the strong heterogeneity of sediment with respect to chemical, physical, and biological characteristics. Lag phase duration depended strongly on the content of inorganic electron acceptors and also on the number of methanogens present at the beginning of the experiment. Maximum and steady state methanogenesis were mainly determined by sediment total nitrogen. As analysis of sediment density fractions revealed that total nitrogen reflected the share of readily degradable macroorganic matter. Conclusion and Outlook   The results imply that the observed methane formation is a function of the temporally changing balance of the availability of electron acceptors and H2, and the share of easily degradable organic matter. For fresh riverbed sediments, the latter may be deduced from total nitrogen content. Overall, the results showed that methane formation by freshly dredged material may well be pre-estimated from standard analytical data within the first few years of deposition. However, the differently degradable organic matter pools will change over time with respect to size, chemical nature and association with the sediment mineral phase. It can thus be expected that the correlations found in this study will not be readily transferable to older materials. Further studies on the gas formation and organic matter quality by older sediments, e.g. from older dredged material disposal sites of known age, should be conducted and results should be combined with existing organic matter degradation models in order to improve the prediction of sediment gas formation over time.     

粘土土壤孔隙大小分布及其与土壤有机质的相关性

Soil pore size distribution(PSD) directly influences soil physical,chemical,and biological properties,and further knowledge of soil PSD is very helpful for understanding soil functions and processes.In this study,PSD of three clayey soils collected from the topsoil(0-20 cm) of Vertisols in Northern China was analyzed using the N_2 adsorption(NA) and mercury intrusion porosimetry(MIP) methods.The effect of soil organic matter(SOM) on the PSD of clayey soils was also evaluated.The differential curves of pore volume of clayey soils by the NA method exhibited that the pores with diameter 0.01 μm accounted for more than 50%in the pore size range of 0.001 to 0.1 μm.The differential pore curves of clayey soils by the MIP method exhibited three distinct peaks in pore size range of 60 to 100,0.3 to 0.4 and 0.009 to 0.012 μm,respectively.In the three clayey soils,the ultramicropores(5-0.1μm) were determined to be the main pore class(on average 35.5%),followed by macropores( 75 μm,31.4%),cryptopores(0.1-0.007μm,16.0%),micropores(30-5 μm,9.7%) and mesopores(75-30 μm,7.3%).The SOM greatly affected the pore structure and PSD of aggregates in clayey soils.In particular,SOM removal reduced the volume and porosity of 5-100 μm pores while increased those of 5 μm pores in the 5-2 and 2-0.25 mm aggregates of clayey soils.The increase in the volume and porosity of 5 μm pores may be attributed to the disaggregation and partial emptying of small pores caused by the destruction of SOM.     

Two new benzofuran derivatives with anti-inflammatory activity from Liriope spicata var. prolifera

Two new benzofuran derivatives, 2-(4′-hydroxybenzyl)-5,6-methylenedioxy-benzofuran () and 2-(4′-hydroxybenzoyl)-5,6-methylenedioxy-benzofuran (), along with 8 known compounds were isolated from 60% EtOH extract of the fibrous roots of Liriope spicata var. prolifera. Their structures were elucidated on the basis of extensive spectroscopic analysis. In an in vitro bioactive assay, the two new benzofuran derivatives showed anti-inflammatory activity. Compounds 1 and 2 exhibited significant inhibitory activity against neutrophil respiratory burst stimulated by phorbol 12-myristate 13-acetate (PMA) with IC₅₀ value of 4.15 ± 0.07 and 5.96 ± 0.37 μM, respectively.     

Post-fire soil respiration in relation to burnt wood management in a Mediterranean mountain ecosystem

After a wildfire, the management of burnt wood may determine microclimatic conditions and microbiological activity with the potential to affect soil respiration. To experimentally analyze the effect on soil respiration, we manipulated a recently burned pine forest in a Mediterranean mountain (Sierra Nevada National and Natural Park, SE Spain). Three representative treatments of post-fire burnt wood management were established at two elevations: (1) “salvage logging” (SL), where all trees were cut, trunks removed, and branches chipped; (2) “non-intervention” (NI), leaving all burnt trees standing; and (3) “cut plus lopping” (CL), a treatment where burnt trees were felled, with the main branches lopped off, but left in situ partially covering the ground surface. Seasonal measurements were carried out over the course of two years. In addition, we performed continuous diurnal campaigns and an irrigation experiment to ascertain the roles of soil temperature and moisture in determining CO₂ fluxes across treatments. Soil CO₂ fluxes were highest in CL (average of 3.34 ± 0.19 μmol m⁻² s⁻¹) and the lowest in SL (2.21 ± 0.11 μmol m⁻² s⁻¹). Across seasons, basal values were registered during summer (average of 1.46 ± 0.04 μmol m⁻² s⁻¹), but increased during the humid seasons (up to 10.07 ± 1.08 μmol m⁻² s⁻¹ in spring in CL). Seasonal and treatment patterns were consistent at the two elevations (1477 and 2317 m a.s.l.), although respiration was half as high at the higher altitude.Respiration was mainly controlled by soil moisture. Watering during the summer drought boosted CO₂ effluxes (up to 37 ± 6 μmol m⁻² s⁻¹ just after water addition), which then decreased to basal values as the soil dried. About 64% of CO₂ emissions during the first 24 h could be attributed to the degasification of soil pores, with the rest likely related to biological processes. The patterns of CO₂ effluxes under experimental watering were similar to the seasonal tendencies, with the highest pulse in CL. Temperature, however, had a weak effect on soil respiration, with Q₁₀ values of ca. 1 across seasons and soil moisture conditions. These results represent a first step towards illustrating the effects of post-fire burnt wood management on soil respiration, and eventually carbon sequestration.     

苹果切片干燥收缩变形的孔道网络模拟及试验

为揭示果蔬干燥收缩变形的传热传质与应力应变的机理，确定果蔬微孔结构特性及内部毛细力等因素对其干燥过程的影响，该研究运用孔道网络方法、热质传递原理和细观力学理论等交叉学科知识，构建了孔隙尺度下果蔬切片干燥收缩变形的孔道网络模型，采用VC++开发孔道网络求解程序，模拟分析了果蔬切片的湿分场、温度场以及应力应变场等情况，并以苹果切片作为果蔬典型代表进行了热风干燥试验及模型验证。结果表明：湿含量、温度和收缩变形率的模拟值与试验值的相对误差小于10%，模型可有效模拟果蔬干燥热质传递与应力应变的收缩变形真实过程，再现了干燥过程中的"非规则收缩变形"现象；孔道网络模拟的湿分场、温度场及应力应变场均呈现为不规则非对称变化规律，产生了明显的干斑、湿斑、非规则干燥前沿等；毛细应力和湿应力对果蔬干燥收缩变形影响较大，其中毛细应力是引起非规则收缩变形的主导因素；孔隙结构参数对果蔬干燥过程影响显著；孔隙率越大，干燥时间越长，毛细应力越小；配位数越大，毛细应力越大，干燥时间越长；孔隙直径分布呈现均一直径分布规律的物料产生的毛细应力大，其次为孔隙直径分布呈现正态分布规律的物料和试验物料分布。研究结果为果蔬干燥品质及工艺优化分析提供了一定的理论基础。