湖库型饮用水安全与生物处理策略

饮用水污染问题日趋严重,本文根据莆田市环保局的统计数据,分析了饮用水污染的原因,提出了利用生物技术对饮用水源进行保护和水质净化,以保障饮用水安全.     

论水环境与水利工程的关系

分析了pH值、侵蚀性二氧化碳、氯化物、硫酸根离子、总硬度等因素对水利工程建筑物的影响,认为水污染不仅影响人类赖以生存的水环境,而且对水利工程建筑物也会产生危害.同时,分析了水利工程建筑物施工过程和建筑物本身对水环境的影响,认为过度建设水利工程也会对水环境产生严重影响.     

Dynamic simulation and optimal control strategy for a parallel hybrid hydraulic excavator

The primary focus of this study is to investigate the control strategies of a hybrid system used in hydraulic excavators. First, the structure and evaluation target of hybrid hydraulic excavators are analyzed. Then the dynamic system model including batteries, motor and engine is built as the simulation environment to obtain control results. A so-called multi-work-point dynamic control strategy, which has both closed-loop speed PI （proportion integral） control and direct torque control, is proposed and studied in the simulation model. Simulation results indicate that the hybrid system with this strategy can meet the power demand and achieve better system stability and higher fuel efficiency.     

Numerical investigation of cavitating flow behind the cone of a poppet valve in water hydraulic system

Computational Fluid Dynamics (CFD) simulations of cavitating flow through water hydraulic poppet valves were performed using advanced RNGk-epsilon turbulence model. The flow was turbulent, incompressible and unsteady, for Reynolds numbers greater than 43000. The working fluid was water, and the structure of the valve was simplified as a two dimensional axisymmetric geometrical model. Flow field visualization was numerically achieved. The effects of inlet velocity, outlet pressure, opening size as well as poppet angle on cavitation intensity in the poppet valve were numerically investigated. Experimental flow visualization was conducted to capture cavitation images near the orifice in the poppet valve with 30° poppet angle using high speed video camera. The binary cavitating flow field distribution obtained from digital processing of the original cavitation image showed a good agreement with the numerical result. Project supported by the National Natural Science Foundation of China (No. 59835160) and Scientific Research Foundation for Returned Overseas Chinese Scholars, State Education Ministry of China (No. 50175097)     

Active disturbance rejection control for hydraulic width control system for rough mill

The highly nonlinear behavior of the system limits the performance of classical linear proportional and integral (PI) controllers used for hot rolling. An active disturbance rejection controller is proposed in this paper to deal with the nonlinear problem of hydraulic servo system in order to preserve fast response and small overshoot of control system. The active disturbance rejection (ADR) controller is composed of nonlinear tracking differentiator (TD),extended state observer (ESO) and nonlinear feedback (NF) law. An example of the hydraulic edger system case study is investigated to show the effectiveness and robustness of the proposed nonlinear controller,especially,in the circumstance of foreign disturbance and working condition variation,compared with classic PI controller.     

水安全视阈下的中原经济区城市水管理体系研究

随着极端气候频繁出现造成的一系列城市水管理问题,以及由此引起的安全隐患,已经摆在中原经济区的经济建设和社会发展日益突出的位置．通过转变水管理观念,在认真分析城市水管理存在问题、明确水管理系统性特征的基础上,必须构建水务一体化的水管理体系,才能确保中原经济区的水安全和经济社会的可持续发展．     

谈谈中国山水画教学中写生的重要性

写生,是山水画教学的基础课程,是一种训练学生独立观察、构图、分析和创作能力、解决形象思维和收集素材的手段,也是造型艺术的一种形式。要搞好山水画教学,必须在继承传统,学习传统技法的基础上,加强写生课的教学。     

水压轴向柱塞马达配流盘的研究

This paper has introduced the developments of water hydraulic axial piston equipments.According to the effects of physicochemical properties of water on water hydraulic components,a novel valve plate for water hydraulic axial motor has been put forward,whose moment exerted by the fluid field between valve plate and bearing plate is balanced entirely.The material screening experiment of valve plate is done on the test rig.Through numerical simulation the effects of some geometry parameters on the performance of water hydraulic motor have been studied.The silencing grooves on the valve plate in water hydraulic motor can reduce the pressure shock and the occurrence of cavitation effectively.It is evident that the appropriate structure should change the wear status between matching paris and reduces the wear and specific pressure of the matching pairs.The specimen with the new type valve plate is used in a tool system.     

高职园林技术专业课程考试改革的探索与实践

高等职业教育高技能人才培养目标是否达到,考试是重要的检验手段,然而,传统的卷面考试基本上只能检验学生知识掌握的程度,而不能体现学生实践技能水平的高低。为此,在园林专业的教学实践中,对考试方法进行了一些改革的探索和实践。     

福州市闽江水源热泵技术应用基础数据库建设

对福州市境内闽江水的水温、水质和水位等重要参数开展测试工作,建立了福州市闽江水源热泵技术应用基础数据库。测试数据显示闽江水温在纵向断面上基本保持一致,相对气温变化稳定,适合作为冷热源。多项水质测试结果显示,主要水质指标均满足水源热泵机组的要求,闽江水存在浊度大和铁离子含量偏高的问题。闽江水位每日变化幅度受潮汐的影响较大,潮差自闽江口向闽江上游逐渐减少,其中马尾段每日最大水位差在2.58~5.34 m之间波动,水位年变化幅度为5.51 m。本研究旨在为福州市闽江水源热泵技术推广应用提供数据支撑。     

浅谈建筑给排水的环保节能

水资源是目前全球各个国家最关注的问题,且随着人类素质和意识的提高,这将成为一个被永远关注的问题。因为它对人类的生存、社会的发展起着决定性的作用,同我们生活息息相关。本文从建筑给排水的角度出发,对其环保、节能的必要性进行了分析,并就如何在建筑物中环保节能的提高水资源利用率,对建筑给排水系统设计和施工过程当中应该采取的部分相应技术手段做了试探性的探讨。     

穆棱河水系鸡西段水体污染分析及其治理措施

依据实际监测结果,对穆棱河水系鸡西段水体污染进行了理论分析,提出水体污染的规划控制途径,为城市建设和环境保护提供依据.     

新型给水管材水力工况对比分析

通过对各种新型给水管材之间水力工况的比较和分析，推得各种管径的新型给水管材与相应公称直径的镀锌钢管单位长度水头损失的比值K，由于管材间水力工况的不同，在工程设计、旅工中更换管材时，不能简单地用相同或相近管径的管材互相替代，而应重新对系统进行水力计算。     

锅炉化学水处理系统的自动控制技术

在介绍了水处理工艺的基础上，结合某厂实际，设计了一套基于组态王6．0组态软件和PLC的SCADA补给水控制系统，使系统的运行和离子交换器的再生达到优化，性能达到生产要求，出水水质稳定，降低了生产成本。     

研究生课程水污染控制工程的课堂教学研究与实践

水污染控制工程是为环境工程专业的硕士研究生开设的专业学位课,本文介绍了该课程的课堂教学研究与实践。     

HCON（CH3）2微量水工艺中的建模和应用

为了提高产品质量,保证对重要生产过程的控制,现代化生产工艺对过程监控系统的要求越来越高．一些与产品质量紧密相关的过程参数需要严格加以控制。以人工神经网络为代表的软测量技术可以容易测得一些相关辅助变量,通过建立一定的数学模型和相应的算法解算,以达到快速、准确地预测所要监测重要参数的目的。     

煤气洗涤水的治理研究

采用氧化 絮凝方法对煤气洗涤水进行了研究 .通过实验选择二氧化氯为氧化剂 ,聚丙烯酰胺和石灰为混凝剂 ,并综合考虑处理效果和药剂费用等各方面因素 ,通过正交实验确定了主要技术参数 .     

中央空调冷却水系统常见的几个问题

本文着重介绍了中央空调冷却水系统中经常出现的一些问题:①由水量损失造成的冷却水中盐分过高影响换热效果、系统出现气蚀现象、甚至系统出现水锤现象;②由设计失误造成水锤和气蚀;③由系统中的含氧量及含盐量过多造成的系统结垢甚至腐蚀等等.针对上述问题从设计、施工和运行等方面提出了应注意的事项和解决办法.     

光合菌处理豆制品废水影响因素的研究

研究了在厌氧及微好氧条件下光合菌对豆制品废水的处理效果，探讨了接种量，废水浓度，废水pH值，处理温度对CODCr却除率的影响，结果表明，在pH值为7．5，30℃，微好氧条件下，光合菌对废水的CODCr去除率最高，且接种量与CODCr去除率成正比。     

冷轧酸碱废水处理工艺及其重要参数的设定和分析

介绍了本钢浦项冷轧薄板有限责任公司酸碱废水处理工艺并详细分析了各工艺点控制参数的设定。该工艺按照这些控制参数进行设定后运行,出水水质指标可以达到或优于国家规定排放标准。