长江流域梯级枢纽泥沙调控关键技术

通过将水沙动力学与水库调度优化理论相结合,围绕长江流域梯级枢纽泥沙调控关键技术开展研究。在改进恢复饱和系数、非均匀沙挟沙力等关键计算模式的基础上,完善并集成长江上游梯级水库群水沙数学模型、长江中下游复杂江湖河网水沙数学模型和典型河段平面二维水沙数学模型,构建了江河湖库水沙输移模拟模块。基于泥沙对防洪、发电、航运和长期使用4个主要目标的影响,构建了长江泥沙优化调控目标函数,进而集成水沙输移模拟模块构建了长江泥沙优化调度模型,并提出了基于预构泥沙信息库、结合BP神经网络的模型求解方法和非劣解集的改进灰靶评价方法。在此基础上,以三峡水库为例,提出了汛期“蓄清排浑”动态运用方案以及长期分阶段泥沙调控策略。     

2002-2018年长江口基本河槽冲刷及形态调整演化趋势

三峡蓄水后清水下泄对长江口河床演变产生何种效应是泥沙研究者普遍关注的问题。在阐述长江口近期来水来沙和边界条件变化的基础上,分析了长江口基本河槽河床冲淤特点、形态演变及其趋势。分析表明,长江口基本河槽发生了全面的强冲刷,河床形态朝宽深比减小的方向发展。各分段基本河槽上、中、下3层河床的冲刷分布,体现了长江口愈向上游段受径流作用相对较大,而愈向下游口门受潮汐动力作用相对较大对河床冲刷影响的特性。在保滩护岸和近期圈围工程与岸线整治工程作用下长江口总体河势仍将继续保持相对稳定;在三峡蓄水后来沙大幅减小的大环境下,基本河槽将连续受到冲刷,河床形态仍将朝窄深方向发展。     

高层结构清水混凝土施工技术要点剖析

结合青岛盛和大厦主体工程梁、板、墙、柱全部为清水混凝土施工的情况,介绍清水混凝土的质量标准、常见的质量缺陷及其监控对策,并重点阐述从模板体系的设计、制作,安装到混凝土匣材料选用、配合比设计,混凝土的浇筑、养护和表面缺陷修补全过程所采取的措施.     

混凝土框架梁控制截面设计弯矩的研究

混凝土框架梁端的实际控制截面位于梁、柱界面处,而不是与梁端相连的柱的轴线处,所以结构模型中所有框架梁的刚接端均应设刚域,使框架梁的计算跨度更合理,使梁端的控制截面与计算截面相一致,使设计能根据梁柱界面处的组合弯矩确定梁端截面配筋.本文对此进行了分析研究,结果可供结构设计参考.     

清澈液体的色度测定

本文采用紫外可见分光光度计测定清澈液体的色度,该方法速度快,准确度高,分辨率好,而且样品用量少,并具有广泛的适用性。     

Fabian Ostner

Fabian Ostner represents a new transnational practice triggered by the experimental and international environment at Auroville which attracts architects from all over the world. Trained in Germany, and having worked in Berlin and Mumbai, Ostner now runs his practice from the former French colony of Pondicherry, a city in south India close to both Auroville and Chennai. He cites the reason for his architectural domicile in India as the charter of Auroville, in its striving to represent a bridge between past and present and, ultimately, human unity. Ostner focuses on bridging traditional building culture with a modern approach to architecture that is often conveyed by his compelling projective images. Copyright © 2007 John Wiley & Sons, Ltd.     

三峡工程防洪调度对水库泥沙淤积影响初探

１９９８年洪水后，人们关心三峡工程的防洪作用以及防洪调度对库区泥沙淤积的影响。以１９５４年洪水为例研究３种不同的防洪调度（即按荆江地区防洪需要调度；按城陵矶附近地区防洪需要调度与非常情况下防洪调度）的水库淤积状况，分析不同防洪调度对水库淤积的影响。分析结果说明三峡水库在长时间的“蓄清排浑”运用中，对少数大水年份采用不同的防洪调度运用方式，对库尾段的淤积仅在短时间内有影响，经长期河床与水流的自动调整，终将维持相对平衡状态。     

AD-4微生物防蜡剂培育与应用

介绍了微生物防蜡剂的培育、室内性能检测及现场防蜡试验过程。用现场油水样中菌种驯化的菌种和实验室菌种配伍、优化、筛选,培育成AD-4微生物防蜡剂。通过室内试验验证,AD-4微生物防蜡剂对现场蜡块的乳化降解作用使蜡块凝固点降低4~8.5℃,原油培养液表面张力降低率30.3%~49.3%,黏度降低35%~50%,原油流动性得到了很大的提高。经现场12口油井试验证明,应用AD-4微生物防蜡剂后,油井电流、负荷下降,示功图显示结蜡现象明显减轻,检泵周期延长,部分井检泵周期可延长到原来的2倍,投入产出比可达1:2.8。     

小浪底水力发电厂清水控制系统

小浪底水力发电厂清水供水系统分为清水池阀门控制系统和回水泵控制系统。该系统采用美国MODICON公司的TSX COMPACT 984-265型PLC。PLC根据所采集的流量，水位，温度等条件自动控制开，停泵的台数，以确保清水供水系统的正常运行。     

Reduction of Patulin Content in Apple Juice Using Activated Carbone

The mycotoxin, patulin （4-hydroxy-4H-furo [3, 2c] pyran-2 [6H]-one）, is produced by a number of fungi common to fruit and vegetable-based products, most notably apples. Patulin contamination within apple products poses a serious health risk to consumers. Studies done on laboratory animals have demonstrated that patulin has a broad spectrum of toxicity, including mutagen city and carcinogenicity. The aim of the experiment was studying influence of selectively acting activated carbon powder--Ercarbon SH （Erbsloh, Germany） which is special produced for lowering HMF （hydroxy methyl furfural）, on reduction of patulin content in clear apple juice. Industrial apple row material with some damaged parts was pressed, juice was pasteurized at 95 ℃ during 2 min. After cooling on 55 ℃, enzymatic treated and clarified juice were filtered by 0.45 [am pore sizes membrane filter, Apple clear juice sample was divided for five parts. The samples of apple juice were diluted to 11.5° Brix and contacted with concentrations of 2, 2.5, 3 and 3.5 g/L activated carbon powder for 30 min. After filtration in the experimental samples, putulin was quantitatively determined by HPLC （high performance liquid chromatography with UV） detector at 276 nm. The research revealed that the best results were achieved by treatment with activated carbon in its powder form at concentration of 2.5 g/L with 30 min contact time.