Development of a mechanistic model for biological nutrient removal activated sludge systems and application to a full‐scale WWTP

In wastewater treatment plants (WWTPs) the production of nitrite as an intermediate in the biological nutrient removal (BNR) process has been widely observed, but not been taken into account by most of the conventional activated sludge models yet. This work aims to develop a mechanistic mathematical model to evaluate the BNR process after resolving such a problem. A mathematical model is developed based on the Activated Sludge Model No.3 (ASM3) and the EAWAG Bio‐P model with an incorporation of the two‐step nitrification–denitrification, the anoxic P uptake, and the associated two‐step denitrification by phosphorus accumulating organisms. The database used for simulations originates from a full‐scale BNR municipal wastewater treatment plant. The influent wastewater composition is characterized using batch tests. Model predictions are compared with the measured concentrations of chemical oxygen demand (COD), NH‐N, NO‐N, NO‐N, PO‐P, and mixed liquid volatile suspended solids. Simulation results indicate that the calibrated model is capable of predicting the microbial growth, COD removal, nitrification and denitrification, as well as aerobic and anoxic P removal. Thus, this model can be used to evaluate and simulate full‐scale BNR activated sludge WWTPs. © 2009 American Institute of Chemical Engineers AIChE J, 2009     

δ-Catenin Participates in EGF/AKT/p21Waf Signaling and Induces Prostate Cancer Cell Proliferation and Invasion

Prostate cancer (PCa) is the second most leading cause of death in males. Our previous studies have demonstrated that δ-catenin plays an important role in prostate cancer progression. However, the molecular mechanism underlying the regulation of δ-catenin has not been fully explored yet. In the present study, we found that δ-catenin could induce phosphorylation of p21^Waf and stabilize p21 in the cytoplasm, thus blocking its nuclear accumulation for the first time. We also found that δ-catenin could regulate the interaction between AKT and p21, leading to phosphorylation of p21 at Thr-145 residue. Finally, EGF was found to be a key factor upstream of AKT/δ-catenin/p21 for promoting proliferation and metastasis in prostate cancer. Our findings provide new insights into molecular controls of EGF and the development of potential therapeutics targeting δ-catenin to control prostate cancer progression.     

磁力泵隔离套充液拉深成形模拟分析

运用板料成形有限元软件,对磁力泵隔离套零件的充液拉深成形过程进行模拟,获得成形后的零件成形极限图(FLD)和侧壁厚度分布图,研究了在确定的压边力、凹凸模圆角半径和摩擦系数下,液室压力、压边间隙对零件成形质量的影响规律。研究表明,当液室压力为40 MPa时,侧壁厚度分布范围在0.932~1.027 mm之间;压边间隙为1.08 mm时,零件的侧壁厚度最大减薄率为8.8%;通过控制液室压力为40 MPa、压边间隙为1.08 mm时,试验件壁厚均匀、减薄率低,获得较佳的成形效果,试验结果也进一步验证了结论的有效性。     

Knockouts of Se-glutathione peroxidase-1 and Cu,Zn superoxide dismutase exert different impacts on femoral mechanical performance of growing mice

The objective of this study was to determine the impact of knockout of Cu,Zn-superoxide dismutase (SOD1) and Se-glutathione peroxidase-1 (GPX1) on murine bone biomechanical properties. Femora samples were collected from wild-type (WT), SOD1-knockout [SOD1(-/-)] and GPX1-knockout [GPX1(-/-)] female mice (9-wk old, n = 7-8 per genotype) to assay for bone enzyme activities and mechanical properties in three point bending. Prior to testing, all mice were fed a torula yeast diet supplemented with 0.4 mg Se/kg as sodium selenite. Compared with the WT mice, SOD1(-/-) mice displayed a series of reductions (p < 0.05): 24% in body mass, 8% in femoral length, 43% in femoral structural strength, and 32% in bending stiffness. When differences in body size were accounted for, femoral failure moment in SOD1(-/-) mice remained lower (p < 0.05) than that of WT. Femoral tartrate resistant acid phosphatase activity in SOD1(-/-) was 47% greater (p < 0.05) than the WT. In contrast, GPX1(-/-) mice showed no significant differences in femoral mechanical properties from those of WT mice. In conclusion, knockout of SOD1 exerted a greater impact on femoral mechanical characteristics than that of GPX1 in growing mice.     

辽宁省中小河流治理综合整治新理念

在中国江河防洪体系中,与大江大河相比,中小河流有着数量多、分布广的特点,目前普遍存在的问题就是因没有经过系统有效的治理,河道萎缩严重、河道内垃圾淤积、河道功能衰退等,常遇洪水下就有可能发生洪涝灾害,所以对中小河流治理是十分必要和紧迫的。文章以辽宁省的中小河流治理工程为对象,探讨建立中小河流长效保护机制以及对中小河流进行治理的措施,为辽宁省中小河流以后的治理工作提供一些参考。     

昆明湖水质变化分析及污染控制对策

颐和园昆明湖是北京重要的水利设施、生物多样性保护基地和旅游娱乐基地,具有重要而又独特的环境及美学功能。但近几年来,昆明湖水质开始恶化,主要体现在其富营养化程度的逐步加大。对昆明湖的水质变化及其原因进行了分析,并提出了其水质改善和保护对策:改善补水水源水质和进行湖泊生态恢复工程。     

海陵水利治理体系和治理能力现代化建设与实践

总结海陵水利十三五期间建设发展,紧扣服务和监管两大发力点,重塑谋、建、管、用四大业务体系扣人、财两大保障体系.剖析海陵水利仍然存在的问题,包括薄弱片区水系治理率低,河道长效管护还不够彻底,区域协同治理不足等.提出了海陵水利十四五期间治理思路,坚持街河并行作为实现幸福河湖的海陵特色路径,统筹河道系统生态治理和管理保护,持续加强智慧水利的投入,推进海陵水利治理体系和治理能力现代化.     

复杂地基处理中化学灌浆及质量控制的研究

在修建高坝水库时,坝基断层处理常用到化学灌浆,化学灌浆是一项复杂的技术措施,为获取化学灌浆的技术参数,进行了分析研究;在前人的研究基础上,结合锦屏一级水电站中所做的化学灌浆试验,从地质条件、浆材性能、灌浆压力等影响灌浆质量的因素入手,对各自的作用机理及相互之间的关系进行了探讨;得到了使灌浆质量达到最高水平的一系列控制和调控灌浆的参数;分析结果表明,化学灌浆加固坝基基础,需采用最优参数组合及其严格的灌浆过程控制,该法是一项实用的坝基加固处理措施,可为复杂地基处理中化学灌浆的设计与施工提供参考依据。     

非政府组织参与减灾的理性考量

 在全球治理的背景下,非政府组织发挥自身的独特优势在构建非工程防灾减灾体系中大有可为。同时,减灾的本意昭示非政府组织可以在减少灾害,减轻灾害损失,摒除不利于减灾的思想和行为等方面发挥作用。在这一前提下,考察我国非政府组织参与减灾的阈失面,启示我们要加强防灾减灾的社会科学研究,强化非政府组织自身建设并建立公共服务社会化机制,为非政府组织参与减灾创设条件。从而,非政府组织参与减灾是防灾减灾非工程措施中的重要部分,对其所做的思考是探索非政府组织能否成为未来中国社会防灾减灾主导力量的重要依据。     

分子蒸馏对高酸值花椒籽油脱酸的初步探讨

利用分子蒸馏装置对高酸值花椒籽油进行脱酸来表明脱酸效果显著,重馏份（油脂）的得率高,对酸值在10mgKOH/g-40mgKOH/g花椒籽油进行脱酸,得到的油脂酸值均小于4mgKOH/g,同时所得到轻馏份（脂肪酸）酸值均在192mgKOH/g-198.5mgKOH/g之间。