不同肥料对毛竹冬笋品质特征的影响

连续使用3种不同肥料3年后对冬笋品质特征影响的研究结果表明：蛋白质平均含量的百分比比对照减少0.2～0.35,还原米糖含量的百分比比对照减少0.05～0.12,脂肪平均含量中只有处理C的百分比比对照减少0.1,可溶性固形物的含量没有明显变化均为7.5%,粗纤维含量的百分比比对照增加0.07～0.1,砷（As）含量为绿色食品控制标准的12%～20%,铅（Pb）含量为绿色食品控制标准的51%～97%,镉（Cd）含量为绿色食品控制标准的58%～74%。     

Evaluating biodegradability of soil organic matter by its thermal stability and chemical composition

The stability of soil organic matter (SOM) as it relates to resistance to microbial degradation has important implications for nutrient cycling, emission of greenhouse gases, and C sequestration. Hence, there is interest in developing new ways to quantify and characterise the labile and stable forms of SOM. Our objective in this study was to evaluate SOM under widely contrasting management regimes to determine whether the variation in chemical composition and resistance to pyrolysis observed for various constituent C fractions could be related to their resistance to decomposition. Samples from the same soil under permanent pasture, an arable cropping rotation, and chemical fallow were physically fractionated (sand: 2000-50 μm; silt: 50-5 μm, and clay: <5 μm). Biodegradability of the SOM in size fractions and whole soils was assessed in a laboratory mineralization study. Thermal stability was determined by analytical pyrolysis using a Rock-Eval pyrolyser, and chemical composition was characterized by X-ray absorption near-edge structure (XANES) spectroscopy at the C and N K-edges. Relative to the pasture soil, SOM in the arable and fallow soils declined by 30% and 40%, respectively. The mineralization bioassay showed that SOM in whole soil and soil fractions under fallow was less susceptible to biodegradation than that in other management practices. The SOM in the sand fraction was significantly more biodegradable than that in the silt or clay fractions. Analysis by XANES showed a proportional increase in carboxylates and a reduction in amides (protein) and aromatics in the fallow whole soil compared to the pasture and arable soils. Moreover, protein depletion was greatest in the sand fraction of the fallow soil. Sand fractions in fallow and arable soils were, however, relatively enriched in plant-derived phenols, aromatics, and carboxylates compared to the sand fraction of pasture soils. Analytical pyrolysis showed distinct differences in the thermal stability of SOM among the whole soil and their size fractions; it also showed that the loss of SOM generally involved preferential degradation of H-rich compounds. The temperature at which half of the C was pyrolyzed was strongly correlated with mineralizable C, providing good evidence for a link between the biological and thermal stability of SOM.     

类人机器人全能运动的稳定性研究

类人机器人全能运动包括不同粗糙平面上的快速行走、越障、踢球、格斗等,稳定性是上述运动的关键环节。本文从分析机器人关节角与零力矩点（ZMP）的关系入手,研究提高机器人运动稳定性的新方法。具体步骤是先粗调校正机器人姿态,然后确定各关节角度,得到保证稳定运动的关节角范围。最后依托韩国GP型机器人进行测试,结果表明了所提出方法的有效性。     

高等农业院校素质教育评价体系的构建

构建素质教育评价体系对高校改革发展具有重要作用。调查显示,农业院校学生迫切需要强化素质教育。农业院校素质教育评价体系的构建与实施应从自身实际出发,针对学生实际,构建科学合理的知识结构,突出学生的综合发展测评。同时,注意助推学校的改革发展,准确合理定位学校的层次、类型、功能和特色,使学校育人目标和社会人才需求目标一致,学校发展目标和师生发展目标相和谐。     

高校图书馆馆藏文献资源建设质量控制研究

提出了新时期高校图书馆强化馆藏文献资源建设质量控制的必要性，并从采访工作、编目工作两大方面详细论述了怎样才能做好馆藏文献资源建设的质量控制工作。     

从农产品消费选择趋向浅谈农产品质量提升之路径选择

党的十九大做出了实施乡村振兴战略的重要部署，这就需要推进农业高质量发展，首要任务是农产品质量的提升，当前农产品消费选择的趋向是追求更安全、高品质、有特色、更健康，文章分析了农产品供给与需求之间的错位问题以及成因，并据此提出通过加强科学研究、推行全程质量控制技术、强化信息服务、加强监督管理等方式来促进农产品质量提升和满足消费需求。     

重组猪抑制素蛋白质中毒素残留检测及其理化稳定性

为探索纯化的重组猪抑制素蛋白质毒素残留情况以及重组猪抑制素蛋白质稳定性,本研究利用鲎试剂、气相色谱和SDS-PAGE方法对重组猪抑制素蛋白质中的细菌内毒素、β-巯基乙醇的残留量及其蛋白质在不同温度、极端p H值和反复冻融条件下的稳定性进行检测。结果显示,经过3次等电点沉淀洗涤后,重组猪抑制素蛋白质中细菌内毒素和β-巯基乙醇的残留量大幅减少。通过在不同温度下的处理发现,重组猪抑制素蛋白质在4℃环境下较稳定,可以长期保存;但在37℃时,稳定性快速下降,随着温度上升而降解加速。通过极端p H值和反复冻融试验发现,重组猪抑制素蛋白质对极端p H值和反复冻融具有较好的耐受性。     

烤烟套种甘薯对烟叶质量、烟薯产量及土壤温湿度的影响

为筛选出适宜与烤烟套种的甘薯品种,解决部分烟区烤烟种植调茬难度大与综合效益低等问题,通过田间大区试验,研究烤烟套种不同甘薯品种对烟叶质量、烟薯产量及土壤温湿度的影响。结果表明,烟薯套种能够明显提升土壤相对含水率和烟叶产量,其相对含水率提高幅度介于12.03%~91.88%,烤烟产量增幅为12.29%~31.26%。烤烟套种甘薯以紫薯产量最高,块根产量达29400 kg/hm ²,且单薯质量大于100 g占总薯重的比例在紫薯中最高。烤烟套种甘薯提升了烤烟中上部烟叶的总糖和还原糖含量,降低了烟碱和总氮含量,有利于改善烟叶内在品质。烤烟套种甘薯降低了上部烟叶含梗率,但增大了上部烟叶叶面密度,以烤烟套种紫薯表现突出。烤烟与紫薯套种,可作为一种烟田增产、烟叶增值和烟农增收的种植模式。     

不同增稠剂对农药可分散油悬浮剂稳定性的影响

为明确不同增稠剂对以矿物油为分散介质的油悬浮体系稳定性的影响,以12.5%丙炔·吡嘧(丙炔噁草酮·吡嘧磺隆)可分散油悬浮剂为对象,通过流变学和多重光散射方法,研究了有机膨润土、有机高分子和气相二氧化硅3类增稠剂单独使用及有机膨润土和其他两类增稠剂分别搭配使用对可分散油悬浮剂物理稳定性的影响。结果表明:所有样品的流动特性指数(n)均小于1,为假塑性流体,具有触变性。除有机膨润土和高分子增稠剂Atlox Rheostrux100组合使用时体系更符合Casson方程外,其余样品均更符合Herschel-Bulkley方程。单独使用时,有机膨润土对保证体系稳定的效果相对较好;Atlox Rheostrux 100和Atlox Rheostrux200两种高分子增稠剂的效果差别较大,其中Atlox Rheostrux 100效果更好,这可能是由分子结构差异造成;两种气相二氧化硅类增稠剂由于不能有效形成氢键,效果较差。将有机膨润土和有机高分子增稠剂组合使用时,体系的稳定性有所提升,其中有机膨润土869和Atlox Rheostrux 100组合使用效果更好,体系具有较高的黏度,且具有良好的触变性,物理稳定性优异;有机膨润土869和疏水气相二氧化硅R974组合使用时则效果没有明显的提升。研究表明,流变学和多重光散射两种方法均能较好地表征可分散油悬浮剂的物理稳定性;新型高分子增稠剂和有机膨润土具有协同作用,将二者合理组合添加能大幅提升可分散油悬浮剂的稳定性。     

Strong functional stability of soil microbial communities under semiarid Mediterranean conditions and subjected to long-term shifts in baseline precipitation

We investigated the effect of soil microclimate on the structure and functioning of soil microbial communities in a Mediterranean Holm-oak forest subjected to 10 years of partial rain exclusion manipulations, simulating average drought conditions expected in Mediterranean areas for the following decades. We applied a high throughput DNA pyrosequencing technique coupled to parallel measurements of microbial respiration (R_H) and temperature sensitivity of microbial respiration (Q₁₀). Some consistent changes in the structure of bacterial communities suggest a slow process of community shifts parallel to the trend towards oligotrophy in response to long-term droughts. However, the structure of bacterial communities was mainly determined by short-term environmental fluctuations associated with sampling date (winter, spring and summer) rather than long-term (10 years) shifts in baseline precipitation. Moreover, long-term drought did not exert any chronic effect on the functioning of soil microbial communities (R_H and Q₁₀), emphasizing the functional stability of these communities to this long-term but mild shifts in water availability. We hypothesize that the particular conditions of the Mediterranean climate with strong seasonal shifts in both temperature and soil water availability but also characterized by very extreme environmental conditions during summer, was acting as a strong force in community assembling, selecting phenotypes adapted to the semiarid conditions characterizing Mediterranean ecosystems. Relations of climate with the phylogenetic structure and overall diversity of the communities as well as the distribution of the individual responses of different lineages (genera) to climate confirmed our hypotheses, evidencing communities dominated by thermotolerant and drought-tolerant phenotypes.