模拟盐碱胁迫对小麦种子萌发的影响

农田土壤盐碱化已经成为影响小麦种子萌发的一个重要因素。利用NaCl和Na2CO3模拟盐碱胁迫对小麦种子的萌发影响实验表明：四种小麦的萌发率均表现出显著差异,并随着浓度的增加而表现出降低的趋势,并与无盐碱胁迫的萌发率表现相一致,其萌发率及萌发耐盐碱性次序高低顺序为：济南17〉淄麦12〉邯6172〉泰山9818。在单一盐或碱胁迫条件下,小麦的萌发率总是随着NaCl或Na2CO3浓度的增加而表现出不同程度的降低。无论以NaCl浓度增加为主还是以Na2CO3浓度增加为主的情况下,小麦种子的萌发均随着浓度的增加受到明显的抑制作用。盐碱复合胁迫对小麦种子萌发的影响机理还缺乏生物学及生理学上的解释,仍需要进行深入研究。     

石羊河流域生态环境的变迁与水资源利用对策

本文对石羊河流域水资源开发利用中存在的问题提出新观点,认为:①人们以往只注意强化地表水控制,削弱了天然地下水库的调节作用;②只注意农田用水,忽视了绿洲生态用水;⑧目前采用的落后灌溉方式造成水资源的严重浪费。针对这些问题,本文提出石羊河流域水资源管理综合决策方案,建立多目标管理决策模型,把该流域划分为16个管理亚区,以绿洲农田生态系统和植被生态系统的需水量为决策变量,对经济发展、开发水资源投资、生态环填改善等方面的9个目标作综合考虑。通过模型的模拟运转,展示了该流域生态环境日趋恶化的状况可以得到有效的控制。     

Pb超富集植物金丝草（Pogonatherum crinitum）、柳叶箬（Lsache globosa）

重金属超富集植物是植物修复技术的核心和前提,但目前国内发现的Pb超富集植物较少,本研究通过野外调查和室内胁迫模拟实验相结合的方法,在国内首次发现并证实金丝草和柳叶箬为Pb的超富集植物。野外调查结果表明;金丝草地上部分Pb含量1 231.80 mg/kg,转运系数达到1.32,柳叶箬地上部分Pb含量1 818.40 mg/kg,转运系数6.5。室内模拟胁迫实验表明：在Pb胁迫浓度为5 000 mg/kg时金丝草和柳叶箬对Pb的转运系数均大于1,而且其地上部分Pb含量也超过1 000 mg/kg的水平。在Pb胁迫浓度为18 000 mg/kg时2种植物体内Pb含量达到最大值,金丝草地上部分和地下部分Pb含量分别达3 789.84 mg/kg和4 964.76 mg/kg,柳叶箬地上部分和地下部分Pb含量分别达3 411.56 mg/kg和1 523.02 mg/kg。     

高铁酸钠电化学合成条件的研究

利用含铁材料为阳极,铜为阴极,NaOH溶液为电解液,于隔膜电解槽中电解制备高铁酸钠.探索了该工艺所必需的各种参数和反应条件,确定了隔膜材料,并对Na2FeO4浓度和电流效率的非一致性变化作出了解释.研究结果表明:在阳极距离为1.3 cm(极距2.3 cm)、阳极电解液浓度为14 mol/L,阴极电解液浓度为4 mol/L、温度为35℃、电压为8～9 V时,电解2 h后得到的Na2FeO4浓度为18.7g/L,电流效率为20%.     

不同温度下约束钢梁的落锤冲击响应分析

研究不同温度和冲击荷载作用下约束钢梁的动力响应问题。利用通用非线性有限元分析程序ANSYS/LS-DYNA,分别模拟了两端固支、一端固支一端轴向弹簧约束的钢梁在不同温度下受到落锤冲击时的动力响应。在温度荷载和冲击荷载联合作用下,分析了位移响应、撞击力时程曲线及冲量等的温度效应。通过撞击力时程曲线分析得出最大撞击力随温度的变化趋势与欧洲规范EC3给出的不同温度下的钢材的屈服强度折减系数的变化趋势相似,钢梁跨中的横向位移随着温度的升高而增加。还分析了高温和冲击荷载联合作用下落锤的撞击速度、不同的质量—速度组合、横向加劲肋对钢梁的变形的影响。     

介质阻挡放电常压降解哈隆的研究

本文以介质阻挡放电的方式产生低温等离子体,利用低温等离子体技术成功地降解了常压状况下的气态ＣＦ２ＣｌＢｒ,ＣＦ２ＣｌＢｒ含量为０．６％的空气在放电１０ｓ的条件下,可使ＣＦ２ＣｌＢｒ达到９５％的降解率。本文研究了常压状况下的ＣＦ２ＣｌＢｒ低温等离子体空间反应机理,以及ＣＦ２ＣｌＢｒ初妈压力,电场强度和外加气体分别对低温等离子体降解ＣＦ２ＣｌＢｒ的影响。     

模糊数学在丹河水环境综合评价中的应用

根据模糊数学的方法,将隶属甬数和隶属度等概念引入丹河水环境评价中,用矩阵分析的方法建立模糊综合评价模式.建立评价因子的因子集、评价集、隶属函数和权重集等模糊集合,对丹河进行了分类和质量标准的划分,根据各污染因子对水质的影响差异确定其权重,对丹河流域水环境模糊综合评价,采用了最大隶属度原则和加权平均原则相结合.结果表明评价结果与实际情况有较好的吻合.     

应用概率物种敏感度分布法研究太湖铜水生生物水质基准

运用概率物种敏感度分布法获得太湖水体中铜的急性水质基准值为14.57μg·L-1,慢性水质基准值为3.26μg·L-1;不同类别物种敏感性存在差异,无脊椎动物较脊椎动物更敏感,甲壳类敏感性大于鱼类。概率物种敏感度分布法与传统的物种敏感度分布法相比,更全面合理地考虑多种毒性效应,曲线拟合效果好,受数据量大小影响较小,结果更加稳定。研究结论可为铜水质标准的修订和太湖流域水环境管理提供技术支持。     

Recovery and reuse of floc sludge for high-performance capacitors

• The feasibility of facile fabrication of capacitor from floc sludge is discussed. • The porous carbon composites are obtained by acidification and KOH activation. • The as-prepared 3D structure has large surface area and optimal pore size. • Admirable specific capacitance and outstanding cycling stability are obtained. In this paper, floc sludge was transformed into porous carbon matrix composites by acidification and KOH activation at high temperature and used as an electrode material for application in capacitors. The effects of different treatment processes on the electrochemical properties of sludge materials were compared. The results of electrochemical tests showed that the sludge electrode exhibited excellent energy storage performance after HNO₃ acidification and KOH activation with a mass ratio of 3:1 (KOH/C). The specific capacitance of the sludge electrode reached 287 F/g at a current density of 1 A/g. In addition, the sludge electrode material showed excellent cycle stability (specific capacity retained at 93.4% after 5000 cycles at 5 A/g). Based on XRD, FTIR, SEM, TEM, and BET surface analysis, the morphology of sludge electrode materials can be effectively regulated by chemical pretreatment. The best-performing material showed a 3D porous morphology with a large specific surface area (2588 m²/g) and optimal pore size distribution, improving ion channels and charge conductivity. According to the life cycle assessment of floc sludge utilization, it reduced the resource consumption and toxicity risk by more than 90% compared with ordinary sludge disposal processes. This work provided a cost-effective and eco-friendly sludge reuse method and demonstrated the application potential of sludge-based materials in high-performance supercapacitors.     

Partial anammox achieved in full scale biofilm process for typical domestic wastewater treatment

• A full scale biofilm process was developed for typical domestic wastewater treatment. • The HRT was 8 h and secondary sedimentation tank was omitted. • Candidatus Brocadia were enriched in the HBR with an abundance of 2.89%. • Anammox enabled a stable ammonium removal of ~15% in the anoxic zone. The slow initiation of anammox for treating typical domestic wastewater and the relatively high footprint of wastewater treatment infrastructures are major concerns for practical wastewater treatment systems. Herein, a 300 m³/d hybrid biofilm reactor (HBR) process was developed and operated with a short hydraulic retention time (HRT) of 8 h. The analysis of the bacterial community demonstrated that anammox were enriched in the anoxic zone of the HBR process. The percentage abundance of Candidatus Brocadia in the total bacterial community of the anoxic zone increased from 0 at Day 1 to 0.33% at Day 130 and then to 2.89% at Day 213. Based upon the activity of anammox bacteria, the removal of ammonia nitrogen (NH₄⁺-N) in the anoxic zone was approximately 15%. This showed that the nitrogen transformation pathway was enhanced in the HBR system through partial anammox process in the anoxic zone. The final effluent contained 12 mg/L chemical oxygen demand (COD), 0.662 mg/L NH₄⁺-N, 7.2 mg/L total nitrogen (TN), and 6 mg/L SS, indicating the effectiveness of the HBR process for treating real domestic wastewater.