不同灌水条件下冬小麦的产量、水分利用与氮素利用特点

了解不同灌水量(次数)处理条件下华北平原地区冬小麦的产量形成、氮素利用与水分利用的特点.在大田相同的施肥量与施肥方式、播前浇底墒水750m3.hm-2条件下,设置春季不灌水、春季灌2水(拔节+开花)和春季灌4水(起身+孕穗+开花+灌浆)3个水分处理(每次灌水定额750 m3.hm-2),分析了不同灌水量(次数)对植株氮素吸收利用、产量、土壤水分动态及利用效率的影响.冬小麦生育期内总耗水量和开花后耗水量均表现为随灌水次数(量)增加而增大的趋势,但耗土壤水量却随灌水增加而显著减少.春季灌水处理的经济产量均显著高于春季不灌水处理,但春灌2水和春灌4水之间无显著差异.水分利用效率(WUE)在春不灌水和春灌2水间无显著差异.但它们均显著高于春季灌4水处理.植株总吸氮量均随着灌水次数(灌水量)的增加而呈现出上升的趋势,春灌2水和灌4水处理的总吸氮量无显著差异,但它们均显著大于不灌水处理.氮素生理效率和氮素收获指数随灌水量(次数)增加略有下降,不同灌水处理之间并无显著差异.春灌2水处理相对春季不灌水处理显著提高了经济产量和植株总吸氮量,水分利用效率并没有明显下降;与春灌4水处理相比,经济产量和植株总吸氮量没有明显降低.但水分利用效率和水分边际效益显著提高.冬小麦节水栽培(春灌2水)有利于节水、氮素高效利用和高产的实现.     

氨法脱硫反应特性的化学动力学分析

对采用氨法脱除烟气中SO2过程的反应特性进行了热力学和动力学分析．结果显示,氨法脱硫反应活化能较低,只要温度控制适当,氨法脱硫具有很高的平衡常数(或转化率)和良好的动力学特性．同时,根据实验结果拟合整理出了实验温度范围内氨法脱硫反应的Arrhenius方程,分析了温度对氨法脱硫反应速率的具体影响．     

厌氧颗粒污泥膨胀床原理特征分析

从污泥床层流态、生化反应动力学、体系物相平衡角度分析了以循环为特征的厌氧颗粒污泥膨胀床反应器的结构特点,基质代谢和酸碱平衡特征,进而得出:高面积(H /A)和回流比(R)是实现反应器较高上升流速的结构和运行指标;回流引起反应器基质代谢特征的变化,同时使反应器处理增强;厌氧颗粒污泥膨胀床的运行方式对调解、平衡系统的碱度、pH值起着积极的作用。     

移动床生物膜反应器内气液传质性能研究

采用移动床生物膜反应器,利用清水进行了在不同悬浮填料体积含率和曝气强度时反应器内气液传质性能研究。结果表明,随着曝气强度增加,传质系数增大,但曝气强度过大,并不利于移动床操作;当填料体积含率大于40%时,氧传质系数出现最大值后逐渐减小。在填料体积含率为30%~50%、曝气强度为4.5~7 m3/(h.m)时,传质效果良好,氧转移效率较高。     

酯类化合物对四膜虫毒性的拓扑研究

提出了拓扑方法,即考虑分子图顶点的性质,直接用酯类化合物的分子碎片的特征值为主元来构建邻接矩阵。定义并计算了酯类化合物的修正的氢连接性指数^mHA及其倒指数^mHB,分析了30个酯化合物对四膜虫的毒性与分子结构之间的关系,结果表明由酯化合物对四膜虫毒性与^mH的回归方程得出的估算值与实验测定值之间能较好地吻合,平均误差为0．22。     

荷电水雾除尘器捕尘效率的实验研究

实验分析了影响荷电水雾除尘器除尘效率的主要因素,在此基础上提出了一种新的除尘效率数学模型,该模型明确地表达了过滤风速、喷雾量以及雾滴荷质比对除尘效率的贡献情况。对实验结果及数学模型的分析表明,对于带有振弦栅的荷电水雾除尘系统,喷雾量对除尘效率的影响比过滤风速及荷质比更为显著,新除尘效率模型的提出对指导生产具有重要意义。实验中同时确定了荷电水雾除尘器最佳操作参数,在粉尘入口浓度为412 mg/m3的情况下,当过滤风速为16 m/s,喷雾量为12×10-3 m3/min,雾滴荷质为3.5×10-4 c/kg时,除尘效率可达99.5%。     

废印刷电路板的静电分选实验研究

金属与非金属材料的分离是回收利用废印刷电路板的关键环节。对废印刷电路板物料的静电分选进行了实验研究。实验以电压、辊筒转速、电晕电极与辊筒之间的距离、静电极位置、电晕电极位置、电晕电极数量等为考察因素,研究各因素对电选效果的影响规律。结果表明,影响金属与非金属材料分离的主要因素是电压、辊筒转速和电晕电极与辊筒之间的距离,对于-0.9 0.45mm的破碎物料,当电压为24kV,辊筒转速为15Hz(54.6r/min),电晕电极与辊筒之间的距离为5.2cm时,得到最大静电分选综合效率67.37%。     

Optimization of thermo-chemical pretreatment and enzymatic hydrolysis of kitchen wastes

The use of abundant waste materials with high carbohydrate content may contribute substantially to reduction of biofuels production cost. The present study aimed at optimizing the combined effect of thermo-chemical pretreatment and enzymatic hydrolysis of kitchen wastes (KW) for maximizing the production of fermentable soluble sugars. To this end, acid pretreatment of KW samples was performed with hydrochloric acid (0–3% HCl) at 30–100 °C for 0–120 min treatment time. Alternatively, alkaline pretreatment of KW samples was performed with potassium hydroxide solution (0–11%) at constant temperature and time (0 °C and 20 min, respectively). KOH pretreatment at such conditions targets to degrade the resistant starch of KW samples. Both acid and alkaline pretreatments were followed by addition of variable levels of enzyme dosage (0–3.6% v/v α-amylase and 0–3.2% v/v amyloglucosidase-AMG) at constant pH, temperature and time (pH = 5, T = 50 °C and t = 30 min, respectively). Based on our results, glucose concentration increased by ～300% after pretreatment with either acid or KOH in combination with enzymatic hydrolysis (2% HCl, 85 °C, 80 min, 0.1% α-amylase, AMG, and 1% KOH, 0 °C, 20 min, 1.1% α-amylase, 0.4% AMG) compared to raw (untreated) KW. Estimating the different Y_G yields at KW loading of 5%, an increase of 192% and 121% for total soluble monosugars and total soluble sugars, respectively, was succeeded compared to untreated KW. The effect of solids loading on the obtained sugar yields using the optimum conditions for thermo-chemical pretreatment followed by enzymatic hydrolysis was also tested resulting to 27.5% increase of the soluble glucose yield when half of the solids loading (2.5%) was used. A decrease of total soluble sugars yield by 32.2% was observed when solely acid hydrolysis at optimum conditions from our previous study was applied at 30% solids loading.     

基于Kaya方法的四个直辖市碳效率评价与比较

应用Kaya恒等式的计算方法对我国4个直辖市2005-2009年的碳效率进行了评价和比较分析,结果显示:4个直辖市碳效率的排序在2005-2009年间没有发生变化,4个城市的碳效率都处于上升态势。     

Connecting with Country in Mungo National Park,Australia: a case study to measure the emotional dimension of experience and place attachment

Connecting people with nature improves well-being, but how people connect with natural places is not well documented. We asked 43 people (19 Aboriginal Australians, 24 non-Aboriginal people) about the messages they received from Country during an interactive experience in the remote Mungo National Park, Australia, and analysed the physical senses, emotions and cognitive processes they mentioned. The physical senses mentioned by most respondents were sight, hearing and motion (particularly walking). These senses helped people receive messages from Country and connect with place. We used the primary-process emotional systems of Panksepp [2010. Dialogues in Clinical Neuroscience, 12 (4), 533–545] as a framework to capture the emotional dimension of experience. Most people reported positive emotions; they spoke about being nurtured by the group and the land (CARE), and the intense joy (PLAY) of being part of the community, being on Country and being accompanied by Aboriginal people. However, our results indicate the framework does not capture the breadth of positive emotions, particularly those associated with connection to place and spiritual experiences. Both groups mentioned cognitive processes reflecting their beliefs, existing knowledge, or sharing and acquiring new knowledge. Our results indicate that the emotional dimension of experience has the potential to measure connection to place, and provide a subjective measure of well-being. More research is needed to document this dimension of experience, and how it changes with context. Our case study provides further insight for those who manage protected areas and seek to enrich the experience of visitors.