《牛津小学英语》中的双性词

water(n.水)water(v.浇水),lif(tv.举起)lif(tn.电梯),last(adj.过去的)last(v.持续),study(n.书房)study(v.学习),watch(n.手表)watch(v.观看),milk(n.牛奶)milk(v.挤奶),fly(v.飞行)fly(n.苍蝇),stop(v.停止)stop(n.停车站),colour(n.颜色)colour(v.上颜色),clean(adj.清洁)c     

初二英语单元重点难点扫描(Units7～9)

1.H e uses a lift to go up and down.(P32)他使用电梯上下(楼)。此句相当于:H e goes up and dow n by lift.这里的lift是名词,意为“电梯”。例如:W e often take the lift to the twelfth floor.我们常常乘电梯到第十二层楼去。注意:give sb a lift意为“让某人搭车”、“帮某人的忙”。lift也可以作动词用,意为“提起”、“举起”、“升起”。例如:The boy can lift a pailof water from the ground.这个男孩能把一桶水从地上提起来。This box is too heavy for m e to lift.这箱子太重,我搬不动。2.H e leaves his hom e and w alk…     

图族Q（Cs,v1,Cl,v1,Ch;n）的σ-指标最小值的研究

在本文中,我们通过对图族Q（Cs,v1,Cl,v1,Ch;n）的σ-指标的研究,刻画出了图族Q（Cs,v1,Cl,v1,Ch;n）的σ-指标的最小值.     

Comparison of the performance of chiral stationary phase for separation of fluoxetine enantiomers

Separation of fluoxetine enantiomers on five chiral stationary phases （chiralcel OD-H, chiralcel OJ-H, chiralpak AD-H, cyclobond 1 2000 DM and kromasil CHI-TBB） was investigated. The optimal mobile phase compositions of fluoxetine separation on each column were hexane/isopropanol/diethyl amine （98/2/0.2, v/v/v）, hexane/isopropanol/diethyl amine （99/1/0. l, v/v/v）, hexane/isopropanol/diethyl amine （98/2/0.2, v/v/v）, methanol/0.2% triethylamine acetic acid （TEAA） （25/75, v/v; pH 3.8） and hexane/isopropanol/diethyl amine （98/2/0.2, v/v/v）, respectively. Experimental results demonstrated that baseline separation （Rs〉1.5） of fluoxetine enantiomers was obtained on chiralcel OD-H, chiralpak AD-H, and cyclobond I 2000 DM while the best separation was obtained on the last one. The eluate orders of fluoxetine enantiomers on the columns were determined. The first eluate by chiralcel OJ-H and kromasil CHI-TBB is the S-enantiomer, while by chiralpak AD-H and cyclobond 12000 DM is the R-enantiomer.     

“三”、“二”、“一”解化学平衡相关计算

化学平衡中的相关计算涉及化学反应速率的计算、物质转化率的计算、物质的实际含量及百分含量的相关计算、平衡常数的相关计算等。应对相关计算的前提是各种规律的识记及综合运用。如在化学反应速率的相关计算中,以aA（g）＋bB（g）→←cC（g）＋dD（g）为例,有以下规律：v（A）：v（B）：v（C）：v（D）=△c（A）：△c（B）：△c（C）：△c（D）=△n（A）：△n（B）：△n（C）：△n（D）=a：b：c：d。     

图族Q（Cs,v1,Cl,v1,Ch;n）的σ-指标的最大值

在本文中，我们通过对图族Q（Cs,v1,Cl,v1,Ch;n）的σ-指标的研究，刻画出了图族Q（Cs,v1,Cl,v1,Ch;n）的σ-指标的最大值．     

A Passage for Comprebension

A man named Smith was sitting on his roof during a flood, and the water was up to his feet. Before long a fellow in a canoe passed and shouted, "Can I give you a lift to higher ground? "No,thanks, " said Smith. "I have faith in God and he will save me." Soon the water rose to Smith's waist. At this point a motor boat pulled up and someone called out, "Can I give you a lift to higher ground? "     

基于一个新核函数的半定规划的内点算法的复杂性分析

Interior-point methods （IPMs） for linear optimization （LO） and semidefinite optimization （SDO） have become a hot area in mathematical programming in the last decades. In this paper, a new kernel function with simple algebraic expression is proposed. Based on this kernel function, a primal-dual interior-point methods （IPMs） for semidefinite optimization （SDO） is designed. And the iteration complexity of the algorithm as O（n^3/4 log n/ε） with large-updates is established. The resulting bound is better than the classical kernel function, with its iteration complexity O（n log n/ε） in large-updates case.     

从一道题谈光电效应的有关问题

题目两束强度相同,频率分别为v1和v2（v1〈v2）的光,垂直射到相同的金属板上,都能产生光电效应,在产生光电效应时,单位时间内选出的光电子数分别为n1和n2．那么,n1和n2的关系是：     

Unsteady flow structure of an airfoil in ground effect

Particle image velocimetry （PIV） experimental results of wake flow structure of a NACA0012 airfoil with small attack angle mounted above water surface are introduced.The experiment was carried out in a small-scale wind-wave tunnel.The diameter of wind-wave tunnel test section is 1.7 m （long） × 0.4 m （width） × 0.4 m （height）.The flow fields around the airfoil were measured under four diffierent conditions by varying the distance between the airfoil and the water surface.The attack angle of the airfoil was kept 10- during the experiment.For each experimental condition,the time series of particle images was captured to calculate continuous evolution of the velocity fields.The velocity fields were ensemble averaged to get the statistic parameters such as mean velocity and vorticity.Typical instantaneous velocity fields for each case are introduced to show the basic flow structure of wind surface flow separation.The aerodynamic loads acting on the airfoil are analyzed qualitatively according to the mean vorticity distribution in the flow field based on the theory of vorticity aerodynamics.The results indicate that the flow structures and drag/lift force of the airfoil alter remarkably with the changing distance between the airfoil and water surface.     

从一道题谈光电效应的有关问题

有这样一道关于光电效应的题目：两束强度相同,频率分别为v1和v2（v1〈v2）的光,垂直射到相同的金属板上,都能产生光电效应,在产生光电效应时,单位时间内逸出的光电子数分别为,n1和n2．那么,n1和n2的关系是     

新目标英语七年级(下)Unit 1知识要点归纳

一、重点词汇guitar n.吉他dance v.跳舞swim v.游泳sing v.唱歌chess n.国际象棋speak v.说(某种语言);说话piano n.钢琴drum n.鼓violin n.小提琴musician n.音乐家talk v.谈话show n.演出;表演draw v.画people n.人;人们home n.家;活动本部adv.到家;在家     

简单答案与提示 高中数学基础知识点训练题

一、代羹与三角91.D,92.C;93.0’94.（略）,99。h。、。5_;.Q。）_。。。。。/9\_。。__1.A..C、D、E;2.2”一103·1十分X一2;96.一84O97.I牛I】98·n—i{（一1.0）.（1.0）}04.41,5.D,6.c;,。n=。,n=f,8·,=。。。x-…二、立体几何（X>1）,9.（0,1）U（1,2）U（3’ OO）。10·一选择题.＊,11.A;12.R;13.（一山,％）,14.P.D另2.B;3.D,4.B;5.A;6.^。。。。。、,。、。CI7.BI.CIg.D！口.C;11.Bf--（二t＊5.2羹＊6.〔211-·1,＊互豆〕,-〔三Z;1了.u。。·l,。u·v,。v,。v.v,--。——。^,。12.A;13。DQ14.AI15.D】IG。A;A.18…     

民族的力量

Not gold, but only man can make A people great and strong; Men who, for truth and honor's sake Stand last and suffer long. Brave men who work while others sleep, Who dare while others fly They build a nation's pillars deep And lift them to the sky.     

七年级（下）Units 3-4词语秀

一、单词秀 1．sleep（1）v．睡;睡觉eg： Be quiet! The baby is sleeping now.安静!那个婴儿现在正在睡觉。 （2）n．睡觉;睡眠eg：     

新目标英语七年级(下)Unit 3知识要点归纳

一、重点词汇train n.火车bus n.公共汽车subway n.地铁ride v.骑n.旅程bike n.自行车minute n.分钟kilometer n.公里;千米new adj.新的drive v.开车car n.小汽车;轿车live v.生活;居住stop n.车站;停止cross v.横过;越过river n.河;江many adj.&pron.许多village n.村庄;村镇bridge n.桥boat n.小船year n.年;岁afraid adj.害怕;畏惧villager n.村民leave v.离开     

笛卡尔积图Tn×Cm的交叉数

两个图G1和G2的笛卡尔积图G1×G2定义为如下的图：V（G1×G2）=V（G1）×V（G2）,E（G1×G2）={（u1,u2）（v1,v2）｜u1=v1且u2v2∈E（G2）,或者u2=v2且u1v1∈E（G1）}．图的交叉数是图论中的一个重要拓扑参数,而确定图的交叉数是一个完全胛一问题．本文确定了若干树Tn（n≤4）与圈Cm的笛卡尔积图的交叉数．     

Twin domination in generalized Kautz digraphs

Let G = （V,A） be a digraph.A set T of vertices of G is a twin dominating set of G if for every vertex v ∈ V ／ T.There exist u,w ∈ T （possibly u = w） such that （u,v）,（v,w） ∈ A.The twin domination number γ＊（G） of G is the cardinality of a minimum twin dominating set of G.In this paper we consider the twin domination number in generalized Kautz digraphs GK（n,d）.In these digraphs,we establish bounds on the twin domination number and give a sufficient condition for the twin domination number attaining the lower bound.We give the exact values of the twin domination numbers by constructing minimum twin dominating sets for some special generalized Kautz digraphs.     

一个关于整数部分的求和公式

设d是非平方正整数,u、v是适合u^2-dv^2=1的正整数,a=u＋v√d,证明了n∑k=0[a^k]=（a^n＋1）（a^n-1）/（a-1）a^n-（n-1）,其中[a^k]是a^k的整数部分。     

Factors influencing the formation of chlorination brominated trihalomethanes in drinking water

The formation of brominated trihalomethanes （THMs-Br） which is proved more carcinogenic than their chlorinated analogues reported was very different at various water qualities. This study was performed to assess the effects of water quality parameters （bromide concentration, pH value and ammonia concentration）, chlorination conditions （chlorine dose, reaction time） and ratios of Br^-/DOC and Br^-/Cl2 consumption on the formation and distribution of THMs-Br in chlorination. The results showed good correlation between the bromine incorporation factor （BIF） n（Br） and Br^-/Cl2 consumption ratio. The formation of total THM （TTHM） was found to＇ decrease with increasing ammonia concentration but to increase with bromide concentration and pH value. The n（Br） trends were significantly affected by the presence of bromide concentration. The effects on the molar yields of THMs were more strongly influenced by bromide concentration and dissolved organic carbon （DOC） concentration than pH value and natural organic matter （NOM） source. High Br^-/DOC and Br^-/Cl2 favor the formation of THMs-Br over chlorinated THMs （THMs-Cl）. The experimental data including the main parameters such as bromide, DOC, ammonia, pH and reaction time were used for developing the predictive model for THMs-Br.