不同收集温度的竹醋液组分及形成过程分析

用4年生毛竹为原材料,经过炭化炉热解后制得竹醋液。测定了不同温度收集的竹醋液的密度、pH值、有机酸含量等基本理化性能,用气相色谱/质谱联用仪进行组分分析,用等离子体原子发射光谱仪测定微量元素含量。结果表明,竹醋液是一种由有机酸、酚类、醛类、酮类、醇类和酯类等组成成分相当复杂的有机混合物。不同收集温度的竹醋液理化性能、化学组分及微量元素含量有差异。因此,在实际生产应用中要根据不同用途进行合理选择。

马占相思花粉离体萌发研究

马占相思(Acacia mangium)是含羞草科(Mimosaceae)金合欢属(Acacia Mill.)树种,在我国的广东、广西、福建以及海南等省(区)大面积种植推广。马占相思用途广泛,其杂交育种工作近年来逐渐受到重视,马占相思花粉研究对其杂交育种成败具有重要影响。该研究以新鲜的马占相思花粉为供试材料,开展不同蔗糖浓度(50、100、150、200、250和300 g·L^(-1))、不同硼酸浓度(100、200和300 mg·L^(-1))以及不同培养温度(26、28和30℃)对马占相思花粉离体萌发影响的研究,同时使用筛选出的马占相思花粉离体萌发的最佳处理,开展对另外3株与初试的马占相思生长发育状况接近的马占相思的花粉活力检测研究,并观察记录马占相思花粉离体萌发特征。结果表明:将刚开放的马占相思花序采回室内阴干,于次日10:00后,用毛笔刷法成功收集大量马占相思花粉,经显微镜观察检测,花粉纯度较高,可以保证后续研究备用;马占相思花粉离体萌发的最佳处理为200 g·L^(-1)蔗糖、100 mg·L^(-1)硼酸、28℃培养温度;马占相思花粉在培养24 h之后,花粉萌发率最高(为94.28%),花粉管最长(为6.0 D);检测3株马占相思的花粉萌发率分别为90.11%、82.31%、85.67%,具有显著差异。该研究结果为今后进一步开展人工控制授粉、选育优良的相思杂交新品种提供了基础。

干燥器法测定人造板中甲醛释放量浅析

甲醛是一种透明有刺激性气味有毒的有机化合物，在常温下是无色气体，有特殊气味，能刺激人的眼睛和呼吸道，剧烈中毒会使人失去知觉，长时间暴露于甲醛浓度较高的空气中还可诱发严重的疾病。为了控制好甲醛的检验过程。

Influence of Temperature, Water Quality and Collector Type on Flotation Performance of a Peruvian Phosphate Ore

The sedimentary phosphate deposit of Bayovar is located in a very dry area of Peru （desert of Sechura） which is close to the Pacific coast. It consists of seven superposed layers （beds） which call for different strategy of concentration. The ore is composed predominantly by apatite （84% in weight basis） plus silicates （16%）. To concentrate phosphate from beds 6-7, it is necessary to carry out further cationic reverse flotation of silicates, at neutral pH, to yield a concentrate which meets market specification. The new process was developed in laboratory scale by a collaborative program conducted between Vale S. A. and the University of Sao Paulo--Brazil. As water resources are very limited at Bayovar region, all the steps of concentration, including flotation, must be performed with seawater which must be continuously recycled. This work addresses some relevant topics related to the use of seawater in the reverse cationic flotation of silicates： influence of temperature, water quality （ageing and chemical composition） and collector type. The results indicate that amido amine works better than ether amine. If flotation is conducted with the former collector, the separation process is able to tolerate changes in temperature （25 ℃-40 ℃） and water quality caused by either evaporation or ageing.

Study of the Firing Temperature of Marajoara Archaeological Ceramics by EPR Associated to INAA Data

The Marajó Island is the largest island of the Marajō archipelago, located in the north of Brazil. In this region, at the end of 19th century, it was identified an archaeological society named Marajora, which occupied the island from 400 to 1,350 AD. It was characterized by a ceramic style recognized by its beauty and exuberance. Until this moment, the physical and chemical analysis studies in this ceramics are scarce and this kind of studies may help archaeological studies performed in the island. With this purpose, this work presents a preliminary study of the firing temperature in the ceramics. For that, the elementary concentrations of 109 samples from Museu de Archaeology and Ethnology Museum of the University of Sáo Paulo and samples collected in the Marajá Island were studied. The samples were analyzed using instrumental neutron activation analysis in which the elemental concentration of Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Rb, Sc, Sm, Ta, Tb, Th, U, Yb and Zn were determined. The interpretation of the results was made using multivariate statistical approaches and showed the existence of three chemical groups. Some samples of each cluster were chosen for the determination of their firing temperatures by electron paramagnetic resonance, in order to verify if different firing temperatures was associated with different elemental groups of ceramic samples. The results showed that there are no statistical differences in the firing temperature between the samples from Archaeology and Ethnology Museum and the contemporary samples of the Marajá Island.

丁香挥发油理化性质、提取工艺参数与其芳香水稳定性的相关性研究

目的采用改进的挥发油提取器提取丁香乳化芳香水,研究不同冷凝温度与不同收集温度下所得乳化芳香水的稳定性及不同温度下丁香挥发油的理化参数与乳化芳香水稳定性的相关性,为丁香挥发油的提取工艺参数的优化提供指导。方法应用表面张力测定仪、乌氏黏度计等测定不同温度下的丁香挥发油的密度、黏度、表面张力、界面张力,并应用稳定性分析仪测定不同提取温度、收集温度下提取所得的乳化芳香水1 h内的稳定性及其粒径,应用多元数据分析分别研究挥发油提取工艺参数、理化性质与乳化芳香水稳定性之间的关系。结果随温度的升高丁香挥发油的相对密度、黏度、表面张力逐渐降低,界面张力呈现先升高后下降的趋势。丁香芳香水的稳定性动力学指数(TSI)与界面张力及冷凝温度呈负相关,与收集温度、密度、黏度、表面张力呈正相关。结论提取过程中收集温度、界面张力及冷凝温度对丁香挥发油与芳香水的稳定性有一定的相关性,可通过控制收集温度、冷凝温度、界面张力来改变挥发油乳化芳香水的油水分离速度,对其提取工艺提供指导。

Experimental study on the effect of porosity on the uniaxial compressive strength of sea ice in Bohai Sea

For the abnormal ice condition in 2009-2010 winter, sea ice samples were collected in a tide ditch outside a port in the east coast of Liaodong Bay, and ice specimens were prepared. Experimental study was carried out with a temperature-control precision of 0.1℃, and 117 columnar-grained ice specimens were loaded along the direction parallel to ice surface under different test temperatures （-4, -7, -10, -13, -16℃） and strain rates ranging from 10^-6 to 10^-2 s^-1 within which the ductile region, duetile-brittle transition and brittle region are contained. The uniaxial compressive strengths, density and salinity of the ice specmens were measured. The results support the curved-surface relationship between the uniaxial compressive strength and porosity within a wide range of strain rate. The curved-surface relationship gives a quantitative description about the variations of the mechanical behavior transition point with ice porosity, and supplies a uniform mathematical representation of uniaxial compressive strength under different failure modes. Besides, it is deduced that abnormal ice condition in 2009-2010 winter will not result in a change of the uniaxial compressive strength of sea ice in Bohai Sea.