光及补料条件对室内管道光反应器中三角褐指藻生长和岩藻黄素积累的影响

【目的】制备富含岩藻黄素的三角褐指藻(Phaeodactylum tricornutum)生物质。【方法】采用470 L室内管道光生物反应器系统,研究自养培养下光源、调光策略、补料培养操作条件对于细胞生长、生物量浓度和岩藻黄素积累的影响。【结果】在采用LED灯、梯度提升照度及重复补料半连续培养模式下,三角褐指藻细胞密度、生物量和岩藻黄素产率最高分别可达3.16×10⁷mL^-1、1.64 g/L和1.90 mg/(L·d),分别是日光灯为光源条件下的2.77倍、3.09倍和2.38倍(P<0.01)。【结论】在管道光生物反应器中获得的自养培养条件,可强化三角褐指藻生物量和岩藻黄素积累,为三角褐指藻积累岩藻黄素的室内可控规模化技术开发提供指导。     

Advanced studies on adaptation of desert shrubs to environmental stress

The combined stress of drought, high temperature and excessive light characterizes the desert area. In order to survive the desert habitat, desert shrubs have evolved a number of special eco-physiological mechanisms to resist environmental stress during long-term evolution. In this paper, adaptation mechanisms of desert shrubs to environmental stress are reviewed in terms of morphological structure, water potential, photosynthesis and water use efficiency, transpiration and stomatal conductance, osmotic adjustment and anti-oxidation protection. In addition, some suggestions for future research are proposed.     

Preliminary study on the origin identification of natural gas by the parameters of light hydrocarbon

The light hydrocarbon composition of 209 natural gas samples and individual light hydrocarbon carbon isotopes of 53 natural gas samples from typical humic-sourced gas and sapropelic-sourced gas in the four basins of China have been determined and analyzed.Some identification parameters for humic-sourced gas and sapropelic-sourced gas are proposed or corrected.The differences of compound-specificδ13C value of individual light hydrocarbon between humic-sourced gas and sapropelic-sourced gas have been founded.The humic-sourced gas has the distribution ofδ13C benzene > -24‰,δ13C toluene >-23‰,δ13C cyclohexane >-24‰andδ13C methyl cyclohexane >-24‰,while the sapropelicsourced gas has the distribution ofδ13C benzene <-24‰,δ13C toluene <-24‰,δ13C cyclohexane <-24‰and δ13C methyl cyclohexane <-24‰.Among the components of C7 light hydrocarbon compound,such as normal heptane(nC7),methyl cyclohexane(MCH)and dimethyl cyclopentane(ΣDMCP),etc,relative contents of nC7 and MCH are influenced mainly by the source organic matter type of natural gas.Therefore,it is suggested that the gas with relative content of nC7 of more than 30%and relative content of MCH of less than 70%is sapropelic-sourced gas,while gas with relative content of nC7 of less than 35%and relative content of MCH of more than 50%is humic-sourced gas.Among components of C5-7 aliphatics, the gas with relative content of C5-7 normal alkane of more than 30%is sapropelic-sourced gas,while the gas with relative content of C5-7 normal alkane of less than 30%is humic-sourced gas.These paremeters have been suggested to identify humic-sourced gas and sapropelic-sourced gas.     

Optimization of a Photo‐assisted Fenton Oxidation Process: A Statistical Model for MDF Effluent Treatment

In the present study, the effects of initial COD (chemical oxygen demand), initial pH, Fe²⁺/H₂O₂ molar ratio and UV contact time on COD removal from medium density fiberboard (MDF) wastewater using photo‐assisted Fenton oxidation treatment were investigated. In order to optimize the removal efficiency, batch operations were carried out. The influence of the aforementioned parameters on COD removal efficiency was studied using response surface methodology (RSM). The optimal conditions for maximum COD removal efficiency from MDF wastewater under experimental conditions were obtained at initial COD of 4000 mg/L, Fe²⁺/H₂O₂ molar ratio of 0.11, initial solution pH of 6.5 and UV contact time of 70 min. The obtained results for maximum COD removal efficiency of 96% revealed that photo‐assisted Fenton oxidation is very effective for treating MDF wastewater.     

轻型动力触探法与静力触探法检测粗砂相对密实度的相关性研究

大量的模型试验和现场试验结果表明,轻型动力触探和静力触探都可用于公路桥涵台背回填中粗砂的密实度检测,而且锤击数N10和锥尖阻力Qc存在着良好的线性关系。为了从理论上揭示两者的相关性的根源,采用拉德模型模拟了两种方法的试验过程,三维有限元数值分析得知,两种触探方法在砂土中的应力、应变和位移场有较大的相似性,验证了轻型动力触探和静力触探在中粗砂中试验结果相关性的必然性。     

海拉尔盆地贝尔凹陷轻质油层录井综合识别与评价

海拉尔盆地贝尔凹陷的油层主要为轻质原油(轻油)层。含轻油砂岩岩心颜色浅,具较浓油气味,普照浅黄色,二次观察含油颜色不明显,油气味变淡或消失,二次荧光普照无荧光颜色。轻油密度范围为0.79～0.82 g/cm³,粘度为1.60～5.40 mPa·s。轻油全烃最大值一般大于0.50%,比值大于3.0。热解分析总烃含量值大于2.00 mg/g,原油轻重指数为2～6。轻油气相色谱分析反映碳数分布范围为nC₈-nC₂₅、主峰碳数为nC₁₈-nC₂₀,进行二次气相色谱分析,色谱呈直线形态。利用单位重量储层的含油量与有效孔隙度交汇图版可识别出油层、油水同层、水层;将原油轻重组分指数与原油的密度、粘度进行回归分析,建立原油类型判别标准及图版,实现轻油层及稠油层的判别。根据静态产能指数和动态产能指数识别高产、工业、低产和偏干4类油层,预测符合率大于90%。     

超轻油页岩渣陶粒的研制与生产工艺方案设计

吉林省桦甸市、农安县油页岩资源丰富。以桦甸市示范电厂油页岩渣为主要原料,用新的烧胀试验方法开展了超轻陶粒的研制,采用自制的新试验装置,烧制出的陶粒接近实际陶粒回转窑水平,并可专门烧制小颗粒陶砂,可比现有烧胀试验方法工作效率提高约50倍;并以国产陶粒设备,提出拟建年产20 万m³陶粒工厂工艺方案设计,对窑炉两端的余热利用提出了可行方案。油页岩渣SiO₂,Al₂O₃,R₂O含量适中,特别是含碳非常少,可以人为地调整发泡剂的用量而控制陶粒的密度,使在1 030～1 100℃范围内烧制出300～500 kg/m³级陶粒或陶砂。     

聚苯乙烯轻质混合土的压缩变形特性试验研究

聚苯乙烯轻质混合土是一种新型的填土材料,国内对其压缩变形特性的试验研究较少。在无侧限抗压强度试验基础上,分析了聚苯乙烯轻质混合土的破坏应变、变形系数与抗压强度的关系;依据单向固结压缩试验,分析了不同配比条件混合土的压缩变形特性,得到压缩屈服应力和压缩模量,可为工程应用提供参考依据     

一种有效的防雷保护系统——综合防雷工程网络

分析了雷电危害地震台站的几种形式和昌平地震台原有避雷设施的状况,介绍了综合防雷工程风络的防雷原理及电容性地线的优点,在实际防雷工作中,综合防雷工程网络取得了较小满意的效果。