The reproductive strategies of an endemic Tibetan fish, Gymnocypris selincuoensis

The reproductive traits of Gymnocypris selincuoensis from Selincuo Lake and its tributaries were investigated in 1997 and 1998. The youngest mature male was age 7 with a standard length (SL) of 172.0 mm, and the youngest mature female was age 8 with a SL of 194.0 mm. The L(50)s Of SL and age at first maturity were respectively 250.32 mm and age 9 for males and 224.71 mm and age 8 for females. The gonadosomatic index (GSI) significantly changed with seasons for mature individuals but not for immature individuals. GSIs of mature females at stages IV and V of ovary development increased with SL and reached a maximum value at the SL range from 370 mm to 390 mm; the GSIs of mature males were negatively correlated with SL. The breeding season lasted from early April to early August. Egg size did not significantly change with SL but increased with the delay of spawning. The individual absolute fecundity varied from 1,341 to 28,002 eggs (mean 12,607+/-7,349), and the individual relative fecundity varied from 6.4 to 42.0 eggs.g(-1) (mean 25.5+/-9.7). The individual fecundity increased with total body weight; it also increased with SL for those of SL less than 370 mm. There was a rest of spawning for mature individuals.

Utilization of several plant proteins by gibel carp (Carassius auratus gibelio)

Six isonitrogenous (gross protein content 35%) and isoenergetic (gross energy content 17 kJ g(-1)) diets were formulated to investigate the effects of inclusion of plant proteins on the gibel carp (Carassius auratus gibelio L.). The plant proteins tested were: soybean cake (SBC), potato protein concentrate (PPC), peanut cake (PNC), cottonseed cake (CSC) and rapeseed cake (RSC). Fish meal (FM) was used as control. In each diet, 27% of the protein was supplied by fish meal, and the rest supplied by the plant protein tested. Each diet was fed to three groups of gibel carp for 8 weeks in a recirculation system. Specific growth rate (SGR) in fish fed the control diet was significantly higher than those in the other groups, and SGR in fish fed the PPC was significantly lower than in fish fed other plant proteins. There was no significant difference in SGR among the other groups. Feeding rates were ranked in the order: RSC > CSC > FM > PNC > SBC > PPC. Conversion efficiency was highest in groups fed FM, SBC and PNC, followed by groups fed CSC and RSC, and was lowest in the group fed PPC. The fish fed PPC showed lower protein retention than those fed FM and SBC. FM showed highest energy retention while PPC showed lowest, There was no significant relationship between SGR and intake of digestible protein (g g(-1) day(-1)), digestible lysine (g g(-1) day(-1)), digestible methionine (g g(-1) day(-1)) or digestible total essential amino acids (g g(-1) day(-1)), suggesting that the differences in SGR could not alone account for any of these variables.

Budgets and dynamics of nitrogen and phosphorus in a shallow, hypereutrophic lake in China

Budgets and dynamics of nitrogen and phosphorus in Lake Donghu were investigated from Oct. 1997 to Sept. 1999. The water residence time was estimated to be 89 days in 1997-1998 and 124 days in 1998-1999. The total external loadings were 53 g N m(-2) yr(-1) and 3.2 g P m(-2) yr(-1) in 1997-1998, and 42 g N m(-2) yr(-1) and 3.1 g P m(-2) yr(-1) in 1998-1999. On average, about 80% of nitrogen and phosphorus input was from sewage outlets, while the rest was from land runoff and precipitation. Ammonium ion was the most abundant form of inorganic nitrogen in the sewage. The nutrient output was mainly through water outflow and fish catch. The percentages of nutrients in fish were estimated to be 7.8%-11.2% for nitrogen and 47.6%- 49.6% for phosphorus. Lake Donghu has a very high nutrient retention (63% for nitrogen and 79% for phosphorus) mainly due to its closure and long water residence time. Sedimentation is an important nutrient retention mechanism in this lake. Using mass balance method, we estimated that denitrification of Lake Donghu involves about 50% of the retained nitrogen. Lake Donghu is rich in inorganic nitrogen and phosphorus and showed great seasonal variation.

A non-linear perturbation model considering catchment wetness and its application in river flow forecasting

A non-linear perturbation model for river flow forecasting is developed, based on consideration of catchment wetness using an antecedent precipitation index (API). Catchment seasonality, of the form accounted for in the linear perturbation model (the LPM), and non-linear behaviour both in the runoff generation mechanism and in the flow routing processes are represented by a constrained nan-linear model, the NLPM-API. A total of ten catchments, across a range of climatic conditions and catchment area magnitudes, located in China and in other countries, were selected for testing daily rainfall-runoff forecasting with this model. It was found that the NLPM-API model was significantly more efficient than the original linear perturbation model (the LPM). However, restric tion of explicit nan-linearity to the runoff generation process, in the simpler LPM-API form of the model, did not produce a significantly lower value of the efficiency in flood forecasting, in terms of the model efficiency index R-2. (C) 1997 Elsevier Science B.V.

Scanning electron microscopy observation of in-device InAs/AlAs quantum dots by selective etching of capping layers

Self-assembled InAs/AlAs quantum dots embedded in a resonant tunneling diode device structure are grown by molecular beam epitaxy. Through the selective etching in a C6H8O7 center dot H2O-K3C6H5O7 center dot H2O-H2O2 buffer solution, 310 nm GaAs capping layers are removed and the InAs/AlAs quantum dots are observed by field-emission scanning electron microscopy. It is shown that as-fabricated quantum dots have a diameter of several tens of nanometers and a density of 10(10) cm(-2) order. The images taken by this means are comparable or slightly better than those of transmission electron microscopy. The undercut of the InAs/AlAs layer near the edges of mesas is detected and that verifies the reliability of the quantum dot images. The inhomogeneous oxidation of the upper AlAs barrier in H2O2 is also observed. By comparing the morphologies of the mesa edge adjacent regions and the rest areas of the sample, it is concluded that the physicochemical reaction introduced in this letter is diffusion limited.

Cognitive models in biomimetic pattern cognition

We describe a new model which is based on the concept of cognizing theory. The method identifies subsets of the data which are embedded in arbitrary oriented lower dimensional space. We definite k-mean covering, and study its property. Covering subsets of points are repeatedly sampled to construct trial geometry space of various dimensions. The sampling corresponding to the feature space having the best cognition ability between a mode near zero and the rest is selected and the data points are partitioned on the basis of the best cognition ability. The repeated sampling then continues recursively on each block of the data. We propose this algorithm based on cognition models. The experimental results for face recognition demonstrate that the correct rejection rate of the test samples excluded in the classes of training samples is very high and effective.

高性能的XML解析器OnceXMLParser

XML(extensible markup language)解析器是分析、处理XML文档的基础软件.研究高性能验证型XML解析器的实现.开发了支持3种解析模型的XML解析器OnceXMLParser,该解析器通过了严格的XML兼容性测试和API兼容性测试.OnceXMLParser具有轻量级体系结构并进行了多方面的性能优化,包括高效的词法分析、基于统计分析的自动机实现、合理的资源分配策略以及语言层次上的优化.性能测试结果表明,OnceXMLParser具有出色的解析性能.

Linux内核的实时支持的研究与实现

目前嵌入式计算的发展对实时多任务操作系统（RTOS）的需求日益迫切，而Linux内核的实时支持研究为迎合这种需求提供了新的可能性，通过从中断控制、实时调度策略、内核抢占机制及细粒度定时器几方面深入研究与实现了Linux内核的实时支持，以使之成为一个较为完善的RTOS。通过把实时部分设计为可配置的单元，以保留Linux原有系统支持及API。另外，为扩展系统适用范围，提出了可支持多实时调度策略的二阶段调度方案，同时指出了当前方案的不足和今后的研究方向。

高效DOM实现的技术研究

DOM是目前为止唯一成为W3C正式标准的XML解析模型。本文充分考虑了DOM模型的特点,设计并实现了一个高性能的支持DOM的XML解析器OnceDOMParser。为了提高DOM实现的性能,我们采用用户堆提高对象管理的效率,减少对象在JVM中创建的数量,并采取了数据的延迟装载策略。OnceDOMParser经过了严格的XML兼容性测试和DOM API兼容性测试,多方面的性能测试表明OnceDOMParser性能优越,其平均吞吐量比目前最流行的XML解析器Xerces高43.7%左右。

基于移动代理的网格计算系统体系结构研究

本文针对物理链路可靠性低、容错性要求高、实体异构程度高的基础设施网格化需求，在系统分析当前主流的网格体系结构的基础上，研究了移动代理（PVM）系统的特性，根据移动代理的特点，提出了基于移动代理的四层网格计算模型MAGC(Mobile Agent Based Grid Computing)，描述了MAGC模型的层次结构，给出了MAGC模型的一个设计方案，分析了MAGC模型的特点，最后介绍了在Aglet平台下实现的原型系统。本文取得的成果主要包括： 第二章提出了基于移动代理的四层网格计算模型(MAGC)，说明了模型中每个层次的功能和层次之间的依赖关系。MAGC模型基于代码迁移，可以解决网络环境恶劣的条件下，网格系统的运行与部署问题。设计了MAGC模型的两个重要基础结构：作业机制和消息机制。设计了移动代理平台抽象层，使网格系统独立于具体的移动代理平台，从而具有一定的可移植性。 第三章在MAGC模型的基础上，进一步给出了MAGC模型的一个实现方案，阐述了MAGC模型中四个子层的功能和组件划分，对每层所包含的组件和组件实现的功能进行了描述，说明了系统的启动方式。 第四章基于MAGC模型构建了一个原型系统，原型系统以IBM开发的Aglets移动代理软件包为基础，实现了作业机制、消息机制和MAGC模型中的移动代理平台抽象层、系统服务层、API层、应用作业层四个子层。

DISTRIBUTION FUNCTION OF A DRIFTING ELECTRON-GAS FOR GENERAL ENERGY-BAND STRUCTURES

The usual application of the Lei-Ting balance equation method for treating electron transport problems makes use of a Fermi distribution function for the electron motion relative to the center of mass. It is pointed out that this presumes the existence of a moving frame of reference that is dynamically equivalent to the rest frame of reference, and this is only true for electrons with a constant effective mass. The method is thus inapplicable to problems where electrons governed by a general energy-band dispersion E(k) are important (such as in miniband conduction). It is demonstrated that this difficulty can be overcome by introducing a distribution function for a drifting electron gas by maximizing the entropy subject to a prescribed average drift velocity. The distribution function reduces directly to the usual Fermi distribution for electron motion relative to the center of mass in the special case of E(k)=($) over bar h(2)\k\(2)/2m*. This maximum entropy treatment of a drifting electron gas provides a physically more direct as well as a more general basis for the application of the balance equation method.

Diamond growth by carbon ion implantation of diamond

Medium energy (5-25 keV) C-13(+) ion implantation into diamond (100) to a fluence ranging from 10(16) cm(-2) to 10(18) cm(-2) was performed for the study of diamond growth via the approach of ion beam implantation. The samples were characterized with Rutherford backscattering/channelling spectroscopy, Raman spectroscopy, X-ray photoemission spectroscopy and Auger electron spectroscopy. Extended defects are formed in the cascade collision volume during bombardment at high temperatures. Carbon incorporation indeed induces a volume growth but the diamond (100) samples receiving a fluence of 4 x 10(17) to 2 x 10(18) at. cm(-2) (with a dose rate of 5 x 10(15) at. cm(-2) s(-1) at 5 to 25 keV and 800 degrees C) showed no He-ion channelling. Common to these samples is that the top surface layer of a few nanometers has a substantial amount of graphite which can be removed by chemical etching. The rest of the grown layer is polycrystalline diamond with a very high density of extended defects.

沈阳市苔藓植物及其对大气质量的指示作用

沈阳是东北地区重要的老工业基地，也是该地区的交通枢纽。本文在对沈阳市进行广泛调查并采集苔藓植物标本的基础上，系统地研究了沈阳市苔藓植物的种类构成、区系、分布格局及其与环境因子的关系，同时利用苔藓植物对沈阳市的大气质量进行了指示。得出的主要结论有： （1）对882份苔藓植物标本进行鉴定，共记录苔藓植物30科67属143种及变种，其中包括苔类（含角苔）9科11属14种，藓类21科56属128种1变种。在记录中发现辽宁省新记录属1个，新纪录种36种，东北新纪录种18种，主要以丛藓科（Pottiaceae）和真藓科（Bryaceae）等地面生藓类为主。 （2）将研究区苔藓植物划分为10个区系成分，其中以北温带分布占据绝对优势，其次为东亚分布和中国特有分布，具强烈的温带性质。通过相似性系数的计算，表明沈阳市苔藓植物区系与鞍山市和抚顺市的亲缘性较大；与上海市和杭州市亲缘性较远。 （3）应用TWINSPAN和DCA，以样点为对象，苔藓植物的重要值为指标，对研究区苔藓植物分布格局进行了分析。结果将样点划分为三个组，从组一到组三，物种丰富度和苔藓盖度逐渐增加。分类与排序的结果与样点的实际物种分布特点基本一致。 （4）采用CCA对沈阳市35种主要地面苔藓植物与环境因子间的关系进行了分析。根据环境因子的影响，将沈阳市主要地面苔藓植物分为两类。同时发现土壤含水量、乔木层郁闭度和人为干扰是影响沈阳市苔藓植物分布的主要因素。 （5）采用大气净度指数法（IAP）和重金属元素（Mn, Fe, Cu, Cr和Pb）化学分析法对沈阳市的大气质量进行了监测。结果表明市区污染远重于郊区，市区西部污染重于东部，南部重于北部；各区以Pb污染最为严重，值得重视。同空气污染指数（API）进行比较，发现IAP与Cu、Pb和API之间具显著负相关性，说明随着重金属含量和API值的升高，IAP值降低，即苔藓植物的种类和盖度下降。以IAP值为自变量，API值为因变量，建立了回归方程y=-0.914x+101.849，进一步说明了IAP值与API值之间的关系。

不同小麦品种（系）中主要矿质元素的含量比较及与品质的关系

采用微波消解、电感耦合高频等离子体原子发射光谱（ICP-AES）的方法,对62份不同小麦品种（系）中锌、铁、铜、钙、钠和钾的含量进行了测定。同时利用红外线品质测定仪对主要品质指标粗蛋白、湿面筋、沉降值进行了测定。结果表明，不同小麦品种（系）中各种矿质元素的含量存在差异，2006年小麦品种中铁含量变幅为18.55-58.19 ug/g，平均为30.83ug/g ，最高与最低的相差39.64ug/g；锌含量变幅为5.70-25.80 ug/g，平均为15.13ug/g ，最高与最低相差20.10ug/g。2008年小麦品种（系）中铁含量变幅为16.68-52.25 ug/g，平均为30.10ug/g，最高与最低相差35.58ug/g；锌含量变幅为12.29-33.47 ug/g，平均为21.11ug/g，最高与最低相差21.18ug/g；钙含量变幅为167.53-348.80ug/g，平均为248.59ug/g，最高与最低相差192.59ug/g；铜含量变幅为2.32-5.83 ug/g，平均为2.98ug/g，最高与最低的相差3.61ug/g；钾含量变幅为1822.71-4414.91 ug/g，平均为2617.87ug/g，最高与最低的相差2634.72ug/g；钠含量变幅为10.25-39.82 ug/g，平均为23.05ug/g，最高与最低的相差29.57ug/g。 两年不同小麦品种（系）中矿质元素的含量分析结果表明：铁、铜、钙、钠和钾含量年际变化不明显,说明小麦对铁、铜、钙、钠和钾的吸收较稳定；锌含量变化较大，可能受环境的影响比较大。分析各矿质元素含量与粗蛋白、湿面筋、沉降值及元素之间的相关关系，结果表明，锌含量与粗蛋白含量呈极显著正相关关系，相关系数为0.317，与湿面筋含量之间呈显著正相关，相关系数达到0.246；铁含量与粗蛋白含量呈显著的正相关关系，相关系数是0.262；铜、钙、钠和钾含量与粗蛋白含量、湿面筋和沉降值之间存在正相关，但不显著，其中钠与沉降值之间为负相关。表明施锌或铁对提高小麦粗蛋白和湿面筋有显著效应，其余矿质元素有促进作用但不明显。 利用RAPD分子标记技术对川育23、41058、川育20及其父母本进行分析，力图从分子水平找到小麦矿质元素含量之间的差异性，琼脂糖电泳结果表明不同的小麦品种（系）间扩增出了差异条带。 以上研究结果，将对筛选“微量营养强化型”小麦新材料，选育“微量营养强化型”小麦新品种奠定基础。 62 different wheat cultivars was digested with HNO3 in a tightly closed vessel heated under micro-wave,then contents of zinc，iron,copper，calcium，sodium and potassium were determined by inductively coupled plasma-atomic emission spectroscopy(ICP-AES)．The main indexes of wheat quality such as total protein、wet glu and sedimentation volume were detected by Infratec 1255 Food & Feed Analyzer at the same time.The obtained results showed that variation for all of the mineral elements concentrations among different cultivars were observed .In 2006, the amplitude variation of the iron content was 18.55-58.19 ug/g,the average value was 30.83ug/g,and 39.64ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 5.70-25.8 ug/g,the average value was 15.13ug/g,and 20.10ug/g between the highest-content cultivar and the lowest one.In 2008, the amplitude variation of the iron content was 16.68-52.25 ug/g,the average value was 30.10ug/g,and 35.58ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 12.29-33.47 ug/g,the average value was 21.11ug/g,and 21.18ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the calcium content was 167.53-348.80ug/g,the average value was 248.59ug/g,and 192.59ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the copper content was 2.32-5.83 ug/g,the average value was 2.98ug/g,and 3.61ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the potassium content was 1822.71-4414.91 ug/g,the average value was 2617.87ug/g,and 2634.72ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the sodium content was 10.25-39.82 ug/g,the average value was 23.05ug/g,and 29.57ug/g between the highest-content cultivar and the lowest one. Analysis was made on the annual variation of mineral elements content in different Wheat cultivars ,the result shows:there is no obvious difference of iron ,copper ,sodium、calcium and potassium concentrations in wheat cultivars, suggesting the absorption of the iron, copper, sodium、calcium and potassium by wheat are relatively steady ,but zinc concentrations change obviously ,maybe influenced heavily by environment . The correlation between mineral elements 、mineral elements and total protein、mineral elements and sedimentation volume as well as mineral elements and wet glut were analysed in this paper, the result showed that there was significant positive correlation between zinc content and total protein (the correlation coefficient is 0.317), positive correlation between zinc content and wet glu (the correlation coefficient is 0.246), positive correlation between iron content and total protein (the correlation coefficient is 0.262). there was positive but not obvious correlation between the contents of copper, calcium, sodium or potassium and total protein, wet glut or sedimentation volume,among which was negative correlation between sodium and sedimentation volume.It was indicated zinc or iron fertilization has prominent effects in improving the total protein in wheat, the rest mineral elements have Non- obvious facilitation. The study then forecasted the genetic difference of different wheat by the molecular marker of RAPD in order to find differences in molecular level. Chuanyu23、41058、chuanyu20 as well as their male and female parents were analysed by RAPD markers,Agarose gel electrophoresis of DNA revealed the appearance of differential bands . The above-mentioned results of this study establish the foundation to screening the new materials of wheat of " strengthening type of micro- nutrition ", and to breeding the new wheat cultivars of" strengthening type of micro- nutrition ".

粒子加速器冷却储存环三维测量控制网中高程基准面的选择

介绍了冷却储存环(CSRm:Cooling Storage Main Ring)工程控制网的建立和测量概况,通过Leica高精度电子水准仪建立高程控制网,并引入到激光跟踪仪的控制网测量中,通过SA(Spatial Analyzer)软件的数据处理和分析,解决了API Tracker3激光跟踪仪"精确找平"和水准测量精度低的难题。