我省人工繁殖绒鳌蟹的经验及技术要点

１９８５年进行河蟹人工繁殖试验研究，取得了初步成功。配制人工海水的适宜盐度为１０‰～１７‰，ＰＨ值为７～８，主要离子每升含量为Ｋ＋１００～２００ｍｇ；Ｎａ＋５１６０～３２０２ｍｇ；Ｃａ（＋＋）４１２～１４４ｍｇ；Ｍｇ（＋＋）７５０～５４４ｍｇ；１１３８～８６０ｍｇ；Ｃ１－９７８２～５６９７ｍｇ；Ｆｅ含量为０．０２～０．０５ｍｇ／Ｌ。长途运输抱卵蟹，气温不宜高于２０℃；培育期水温保持在１６℃左右。蚤状幼体培育时期，温度应保持在２１～２５℃；ＰＨ值在８．５０以下，ＮＨ３－Ｎ在１．５ｍｇ／Ｌ以下；ＮＯ２－Ｎ为０．２ｍｇ／Ｌ以下。采用１／１０００～１／１００００浓度的新洁尔灭，防治蟹病，在１～４小时内产生良好效果。     

工业冷却水中除锰、除铁的试验研究

研究了无烟煤－石英砂滤料接触氧化法除工业冷却水中锰、铁的工艺条件。滤料粒径０５ｍｍ～１０ｍｍ，滤床高８００ｍｍ（无烟煤、石英砂滤料各４００ｍｍ），滤速１０ｍ／ｈ～１２ｍ／ｈ，工作周期９６ｈ，反冲洗强度１０Ｌ／（ｍ２·ｓ），反冲洗时间５ｍｉｎ～７ｍｉｎ，出水Ｍｎ２＋浓度为００４ｍｇ／Ｌ以下，去除率可达９０％以上，总铁浓度为痕量。     

风力离心泵提水机组的试验研究

我国研制的风力离心泵提水机组由一台垂直轴三叶片可变几何型风车（ Ｃｐ ＝ ０－３５ ，λ＝ ２－４）和一台低速立式离心泵（ 额定转速５００ｒ／ｍｉｎ ，额定流量４０ ｍ３／ｈ，额定扬程６ ｍ） 以三角皮带联接组成．现场试验和生产考核证明机组有良好的匹配特性和运行状况．此种机组流量大，扬程适中，在灌溉等方面有广阔的应用前景     

混凝土短期荷载下变形的一个本构模型

（接上期）５　应力—应变增量关系加载曲面一般地表示为：　　ｒ２＝３ｒ２ｔ３－４（１－ｎ２）ｓｉｎ２θ（３４）式中的ｒｔ＝±ａｔ＋ｂｔσｍ＋ｃｔσ２ｍ－ｄｔ，等号右边的正、负号的选取应使得在σｍ的定义域内，ｒｔ≥０。分析二次曲线的系数ａｔ，ｂｔ，ｃｔ，ｄｔ可知，只需将上式写成：　　ｒｔ＝ｄｔ｜ｄｔ｜ａｔ＋ｂｔσｍ＋ｃｔσ２ｍ－ｄｔ（３５）加载曲面函数可写成：Ｆ（σｉｊ，ｆｃ）＝ｒ２１－４３〔１－ｎ２（σｍ）〕ｓｉｎ２θ－ｄｔ（ｆｃ）｜ｄｔ（ｆｃ）｜ａｔ（ｆｃ）＋ｂｔ（ｆｃ…     

黄河下游排沙能力的统计模型

本文题目为排沙能力的统计模型是基于输沙平衡方程式。文章叙述影响河段排沙能力α，即下站与上站输沙率之比，其主要因素为：①上河段排沙比（α０）；②来沙粒径（ｄｉ）；③本河段水流高蓄流量（ΔＱ）；④本河段前期淤积量（ｎ－１／Σ０△Ｗｓ）；⑤来沙粒径不均匀系数（σｄ）。本河段排沙能力的统计模型表示为α＝σ＾ｒｄｅ＾Ａα０＋Ｂ√ｄｉｎ－１／Σ０△Ｗｓ－Ｃ√ｄｉ－Ｄ△Ｑ＋Ｅ式中Ａ，Ｂ，Ｃ，Ｄ，Ｅ，γ－待定系数     

推求水泵型号的简易方法

水泵，作为一种通用水力机械，已应用到了国民经济的各行各业，特别是用途广泛的离心泵。但在许多单位，由于对水泵维护不够或长时间使用，水泵没有了铭牌，不知其型号，对其性能的了解、使用变得尤为困难。下面，就无铭牌的水泵的型号，介绍一种简易的推求方法，供同行参考。首先，利用下面估算公式，求流责转速和扬程等有关参数：１．流量式中：Ｆ－一泵进口面积（米勺Ｄ——泵进口直径（米）Ｖ——泵进口流速（米／秒）。一般为２．５－３．０米／秒，取Ｖ＝２．８米／秒，则：Ｑ＝２．２Ｄ２（立方米／秒）２．转速可查下表求得：３．扬…     

斜井开挖出渣效率与进尺

１斗车容量提升计算（１）一次提升斗车数：n１＝CVn２Vg（１）式中n１—一次提升斗车数；V—１h出渣量，m３；C—出渣不均匀系数，取１．２５；—斗车充盈系数，取０．９；n２—１h内提升次数，n２＝３６００／h；Vg—斗车容量，m３；T—一次提升循环时间，s。（２）单钩提升：T＝２LVa＋t１＋t２（２）式中T—斗车一次提升循环时间，s；L—斜井提升长度，m；Va—卷扬机平均提升速度，m／s，规范规定不大于２m／s，这里取２m／s；t１—斗车装载时间，s，取决于装岩机的生产率；t２—井口调斗车时间，s，一般取２５s。２轨道式铲…     

大桥桩基坐标计算问题

~~＝６３６１３２．７１６２＋０．３０×０．７１９１４＝６３６１３２．９３１９F（Y）＝E１（Y）＋０．３０×sin４４°１'０．７〃＝４８４０３２．５０８５C１（X）＝F（X）＋３．１２５×cos１３４°１８'２６〃＝６３６１３０．７４８９C１（Y）＝F（Y）＋３．１２５×sin１３４°１８'２６〃＝４８４０３４．７４４８C２（X）＝F（X）＋（６．５＋３．１２５）×cos１３４°１８'２６〃＝６３６１２６．２０８８C２（Y）＝F（Y）＋（６．５＋３．１２５）×sin１３４°１８'２６〃＝４８４０３９．３９２６同理可以求得D１…     

内循环生物流化床处理生活污水的试验研究

采用内循环三相好氧生物流化床反应器进行了生活污水的处理试验。在稳态运行状况下，当进水平均ＣＯＤ为２２５ｍｇ／Ｌ，ＨＲＴ为０５ｈ和１０ｈ时，出水ＣＯＤ平均分别为３３ｍｇ／Ｌ和２１ｍｇ／Ｌ，ＳＳ平均分别为２４ｍｇ／Ｌ和１９ｍｇ／Ｌ；生物浓度平均为６０２ｇＶＳＳ／Ｌ，有机物去除容积负荷可高达９３ｋｇＣＯＤ／（ｍ３·ｄ），氧气的传质系数ＫＬａ高达８７６ｈ－１。尽管停止曝气达１０ｄ之久，内循环生物流化床可在一周内恢复正常运行。在本试验中，载体流失量极少，可忽略不计。试验结果表明，内循环生物流化床是一种适合中国国情的高效能、低能耗的废水处理工艺。     

谈谈地埋管道灌溉工程设计施工的有关问题

谈谈地埋管道灌溉工程设计施工的有关问题１单井控制面积的确定１．１设计灌水定额的确定灌水定额应根据当地灌溉试验资料确定，无资料地区可按下式计算：ｍ＝１０００ｙ．ｈ（β１－β２）式中、ｍ）──灌水定额，（ｍ３／ｈｍ２）；ｙｓ──计划湿润层土壤于容重。（ｋ...     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

Serial discontinuities in a Rocky mountain river. I. Distribution and abundance of plecoptera

Samples were taken year-round at eleven sites along the altitudinal profile (2900-1400 m a.s.l.) of the Gunnison River, a 329 km tributary of the Colorado River, to document the distribution of the Plecoptera and to evaluate responses to hypolimnial-release dams in the headwaters and middle reaches. Twenty-two species were present, with the greatest species richness occurring in an unregulated segment upstream of the middle reach dams; average nymphal biomass over the study period (175 organisms, 395 mg dry mass m^?2) was also greatest in this segment. Only four species (58 organisms, 48 mg m^?2) were present in the tailwaters of the headwater dam and values were greatly reduced (nine species; 35 organisms, 180 mg m^?2) below the middle reach dams. The stonefly community recovered ca. 80 km downstream from the last dam (15 species; 244 organisms, 250 mg m^?2), apparently in response to natural resetting of environmental conditions corresponding to those above the middle reach dams. At the most downstream site (11) only four species (four organisms, 16 mg m^?2) were present. The observed distributional pattern is a classic serial discontinuity in response to hypolimnial stream regulation in a temperate latitude river.     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.     

浙江省水域调查录入系统的设计和应用

浙江省水域调查录入系统将调查数据与电子地图相整合,对分类水域数据进行统计计算,并对输入数据进行合理性和完整性检查,得到调查范围内现有水域的详细数据,实现了水域调查数据输入、计算、统计和查询的数字化管理,提高了工作效率和工作质量,为各地下阶段水域保护规划编制和水域管理工作提供了数据支持。对该系统的设计原则、功能和技术设计等作了介绍。     

基于CT-连续加荷水泥乳化沥青混凝土细观损伤规律研究

利用CT技术对水泥乳化沥青混凝土的细观损伤过程进行实时扫描观测,获得了混凝土试件在连续加荷下的CT图像。通过采用直观分析法、CT数分析法、CT数与损伤变量关系3种方法分析表明,水泥乳化沥青混凝土的破坏过程可分为压密、扩容、裂纹扩展、破坏4个阶段,同时混凝土在受压过程中具有韧性,在极限荷载之前各断面处于压密和微扩容的强化阶段,极限荷载之后混凝土从损伤到破坏发展比较平稳。     

Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered. __________ Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008).     

The flood pulse advantage and the restoration of river-floodplain systems

The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed.