鱼类洄游通道恢复——国外的经验及中国的对策

简要介绍了鱼类洄游和鱼类洄游通道恢复的概念及类型。从法律与政策、资金筹措、恢复方法、恢复效果监测评估、信息交流与公众参与等5个方面介绍了欧盟、美、日、澳大利亚等国在鱼类洄游通道恢复方面积累的先进经验和成功实践,并在此基础上提出了我国鱼类洄游通道恢复应采取的对策:开展鱼类洄游通道恢复的立法和政策制定工作,加强鱼类洄游通道恢复工作的法律保障力度;开展流域阻碍鱼类洄游的障碍物调查和影响评价,制定流域鱼类洄游通道恢复规划;探索建立和完善多元化投入机制;加强鱼类洄游通道恢复研究能力建设,建立科学的技术支撑体系;开展

Classical plume theory: 1937-2010 and beyond

Developing a theoretical description of turbulent plumes, the likes of which may be seen rising above industrial chimneys, is a daunting thought. Plumes are ubiquitous on a wide range of scales in both the natural and the man-made environments. Examples that immediately come to mind are the vapour plumes above industrial smoke stacks or the ash plumes forming particle-laden clouds above an erupting volcano. However, plumes also occur where they are less visually apparent, such as the rising stream of warmair above a domestic radiator, of oil from a subsea blowout or, at a larger scale, of air above the so-called urban heat island. In many instances, not only the plume itself is of interest but also its influence on the environment as a whole through the process of entrainment. Zeldovich (1937, The asymptotic laws of freely-ascending convective flows. Zh. Eksp. Teor. Fiz., 7, 1463-1465 (in Russian)), Batchelor (1954, Heat convection and buoyancy effects in fluids. Q. J. R. Meteor. Soc., 80, 339-358) and Morton et al. (1956, Turbulent gravitational convection from maintained and instantaneous sources. Proc. R. Soc. Lond. A, 234, 1-23) laid the foundations for classical plume theory, a theoretical description that is elegant in its simplicity and yet encapsulates the complex turbulent engulfment of ambient fluid into the plume. Testament to the insight and approach developed in these early models of plumes is that the essential theory remains unchanged and is widely applied today. We describe the foundations of plume theory and link the theoretical developments with the measurements made in experiments necessary to close these models before discussing some recent developments in plume theory, including an approach which generalizes results obtained separately for the Boussinesq and the non-Boussinesq plume cases. The theory presented - despite its simplicity - has been very successful at describing and explaining the behaviour of plumes across the wide range of scales they are observed. We present solutions to the coupled set of ordinary differential equations (the plume conservation equations) that Morton et al. (1956) derived from the Navier-Stokes equations which govern fluid motion. In order to describe and contrast the bulk behaviour of rising plumes from general area sources, we present closed-form solutions to the plume conservation equations that were achieved by solving for the variation with height of Morton's non-dimensional flux parameter Γ - this single flux parameter gives a unique representation of the behaviour of steady plumes and enables a characterization of the different types of plume. We discuss advantages of solutions in this form before describing extensions to plume theory and suggesting directions for new research. © 2010 The Author. Published by Oxford University Press on behalf of the Institute of Mathematics and its Applications. All rights reserved.

五氯苯酚在武汉东湖底质颗粒物上的吸附研究

通过静态吸附实验,研究了五氯苯酚在武汉东湖底质颗粒物上的吸附行为,并考察了pH值、颗粒物浓度、盐度和腐殖酸对吸附行为的影响.结果表明,25℃时五氯苯酚在该颗粒物上的吸附行为可用Freundlich吸附等温式描述,在pH值3.0~10.0范围内,五氯苯酚在颗粒物上的平衡吸附量先减小后又缓慢增加;颗粒物浓度在0.1~2.0g.L-1之间变化时,东湖底质颗粒物对五氯苯酚的吸附具有浓度效应;腐殖酸和盐度在一定范围内对五氯苯酚在颗粒物上吸附行为的影响为先促进其平衡吸附量增加,然后这种促进作用趋于缓和.

养殖乌鳢类立克次体分离纯化的初步研究

国家自然科学基金 (No.3 0 3 710 91)资助

宁夏沙坡头地区藻类及其分布

通过野外采样，室内培养、观察、鉴定。研究了沙坡头地区藻类多样性和分布特点，并为当地藻类资源利用提出建议．研究发现沙坡头地区藻类植物共计40种（包括1变型），其中蓝藻17种，绿藻10种，硅藻9种，裸藻4种，全为普生种，陆地生境中种类最丰富．亚气及陆地生境中蓝藻在种类数（除灌溉林地结皮）、生物量方面占主导地位；贫瘠水体生境中硅藻占主要地位，营养较丰富水体中绿藻处于优势地位．另外，陆生生境中多以具鞘微鞘藻Microcoleusvaginatus为优势种，小席藻Phormidiumtenue为主要种．

黑鲷饲料中最适蛋白质含量及动、植物蛋白比的研究

于1988年7月—8月和1989年7月—8月，以酪蛋白为蛋白源，采用蛋白含量梯度法进行黑鲷饲料中最适蛋白质含量研究。结果表明，黑鲷幼鱼饲料中，蛋白质的最适含量约为50．19％。1988年8月—9月和1989年8月—9月，以玉筋鱼为动物蛋白源，以花生饼粉为植物蛋白源，饲料中总蛋白质含量相等，进行黑鲷饲料中最适动、植物蛋白比研究。结果表明，黑鲷幼鱼饲料中，动、植物蛋白的最适比例为1.00：0.89－0.96。

满江红鱼腥藻的异养生理

设计了一个经机械处理而获得蓝藻无菌培养物的方法,利用这一方法获得满江红鱼腥藻(Anabaena azollae)的无菌培养物。满江红鱼腥藻的无菌培养物能以果糖、葡萄糖或者蔗糖为底物,在黑暗中进行化能异养生长。将适应了光能自养生长的培养物转移至黑暗中异养生长时,以NaNO_3为氮源时的生长速率比以空气中的氮气为氮源时高;然而适应了化能异养生长的培养物以空气中的氮气为氮源时生长更佳。搅拌促进生长。满江红鱼腥藻在黑暗中生长半年后,叶绿素a的含量降至光照下生长时的1/3-1/4。满江红鱼腥藻在5500勒克斯光照下

Lean product development in practice: Insights from 4 companies

This paper aims to elucidate practitioners' understanding and implementation of Lean in Product Development (LPD). We report on a workshop held in the UK during 2012. Managers and engineers from four organizations discussed their understanding of LPD and their ideas and practice regarding management and assessment of value and waste. The study resulted in a set of insights into current practice and lean thinking from the industry perspective. Building on this, the paper introduces a balanced value and waste model that can be used by practitioners as a checklist to identify issues that need to be considered when applying LPD. The main results indicate that organizations tend to focus on waste elimination rather than value enhancement in LPD. Moreover, the lean metrics that were discussed by the workshop participants do not link the strategic level with the operational one, and poorly reflect the value and waste generated in the process. Future directions for research are explored, and include the importance of a balanced approach considering both value and waste when applying LPD, and the need to link lean metrics with value and waste levels.

Numerical analysis of gain saturation, noise figure, and carrier distribution for quantum-dot semiconductor-optical amplifiers

The gain saturation behaviors and noise figure are numerically analyzed for quantum-dot semiconductor optical amplifiers (QD-SOAs). The carrier and photon distributions in the longitudinal direction as well as the photon energy dependent facet reflectivity are accounted in the rate equations, which are solved with output amplified spontaneous emission spectrum as iterative variables. The longitudinal distributions of the occupation probabilities and spectral-hole burning are presented for electrons in the excited and ground states of quantum dots. The saturation output power 19.7 dBm and device gain 20.6 dB are obtained for a QD-SOA with the cavity length of 6 rum at the bias current of 500 mA. The influences of them electron intradot relaxation time and the QD capture time on the gain spectrum are simulated with the relaxation time of 1, 30, and 60 ps and capture time of 1, 5, and 10 ps. The noise figure as low as 3.5 dB is expected due to the strong polarization sensitive spontaneous emission. The characteristics of gain saturation and noise figure versus input signal power for QD-SOAs are similar to that of semiconductor. linear optical amplifiers with gain clamping by vertical laser fields.

高温气冷堆He载气中H_2和CO转化实验研究

研究了H＿2和CO在CuO－ZnO＿Al＿2O＿3催化床中转化成H＿2O和CO＿2的实验装置和实验结果，论证了不同床层工作温度、系统压力、杂质浓度、流量及露点温度等因素对氧化铜床工作性能的影响；测得了H＿2和CO在CuO－ZnO－Al＿2O＿3床上的转化特性曲线等变化规律，获得了转化容量、工作周期和转化效率等实验数据，确定了最佳运行参数。结果表明，使用CuO＿ZnO－Al＿2O＿3床可使净化后的H＿2和CO的体积分数都小于2×l0￣（－6），满足高温气冷堆的净化要求。为高温气冷堆中氧化铜床装置提供了可靠的设计数据。

水土保持耕作及施肥对盛花期大豆光合生理的影响

依据陕西安塞田间试验,采用LI-6400便携式光合仪,在自然条件下对黄土丘陵区旱作农田传统翻耕化肥(CF)、翻耕有机肥(CM)、翻耕无肥(CN)、免耕化肥(NF)、免耕有机肥(NM)、免耕无肥(NN)等处理下盛花期大豆叶片的净光合速率、气孔导度、水分利用效率及影响因子日变化进行了研究。结果表明:6种不同处理的大豆叶片净光合速率日变化均为双峰曲线,峰值分别在11:30、16:00出现。NM、NF处理对提高大豆净光合速率有明显的促进作用,其中以有机肥(NM)最为显著。气孔导度与蒸腾速率之间达极显著正相关(P<0.01,r=0.9994)。气孔导度日变化也为双峰,峰值分别出现在11:30、16:00。不同处理下,大豆的水分利用效率呈单峰曲线,峰值出现在10:00,低谷出现在13:00以后。其中,NF、NM处理能显著提高大豆盛花期的水分利用效率。相关分析表明:气孔导度、蒸腾速率、叶温、光合有效辐射及基于叶温的蒸汽压亏缺是大豆光合作用的促进因子,而胞间CO_2浓度、空气CO_2浓度、空气相对湿度则为主要的限制因子。CF、NF处理在8:30~10:20和13:00,CM、NN处理在8:30、11:30~13:00、17:...

黄土高原丘陵沟壑区不同土地利用模式对土壤氮素淋溶的影响

通过对黄土高原丘陵沟壑区不同土地利用模式土壤剖面NO-3-N、NH+4-N、有机质和全氮分布的测定,论述黄土高原丘陵沟壑区不同土地利用模式对土壤氮素淋溶的影响,对当地农业发展提出建议。结果表明:在200 cm内土壤NO-3-N最大值都出现在200 cm处,其中日光温室最大为20.36 mg/kg。土壤NH+4-N在200 cm内是较均匀的分布在10~25 mg/kg。不同土地利用模式对土壤剖面土壤NH+4-N、有机质和全氮分布没有影响。随着深度的变化对土壤NH+4-N分布也没有影响。土壤有机质和全氮在土壤剖面的分布是,随着深度的增加而减少,60 cm以下有机质保持在1.07~5.95 g/kg,全氮保持在0.12~0.35 g/kg。根据试验结果得出,土壤氮素淋溶的主要成分是NO-3-N,土壤NO-3-N淋溶程度与降雨、灌溉、施肥量呈正比,在坡地的淋溶较少。

咪唑衍生物为配体的铜(I)配合物合成及光物理性质

本论文以咪唑衍生物为配体,合成了新型Cu(I)中性配合物和对应的离子型配合物，考察了它们的光物理和电化学性质。具体工作如下： 设计与合成了分别以2-(2'-吡啶基)苯并咪唑(Hpbm)和2-(2'-喹啉基)苯并咪唑(Hqbm)为配体的Cu(I)中性配合物和四氟硼酸根为抗衡离子的离子型配合物。配合物的晶体结构表明中心铜离子均为扭曲的四面体配位构型，中性配合物的咪唑环中的键长趋于平均化。所有配合物在20wt%浓度的PMMA薄膜中的最大发射处于518.5-597.5nm之间，发光效率为0.097-0.249, 磷光寿命为11.7-25.9µs。中性配合物与对应的离子型配合物相比，其紫外可见吸收光谱发生红移，光致发光光谱发生蓝移。 以2, 2'-联苯并咪唑为配体(H2dbm)，设计和合成了双核和单核Cu(I)配合物，其中双核配合物Cu2(dbm)(PPh3)4在二氯甲烷溶液和PMMA (20 wt%)薄膜中均表现为蓝光发射，在20wt%浓度的PMMA薄膜中的最大发射为448.5和475.5nm。单核离子型配合物[Cu(Hdbm)(PPh3)]2[BF4]在20wt%浓度的PMMA薄膜中的最大发射分别为511，发光效率分别为0.150, 磷光寿命分别为12.0。