Phosphorus in plant physiology P content of plants Approximately 0.2% of plant dry weight is P Plants require a relatively large amount of P. The phosphate concentration in the cytosol is maintained at fairly constant concentrations in the 5 to 8 mol/m3 regardless of the external phosphate concentration except under severe P deficiency. By contrast is the vacuolar phosphate concentration

The BIOTOL team This series of books has been developed through a collaboration between the Open universiteit of the OPEN UNIVERSITEIT, THE NETHERLANDS Netherlands and University of Green wich (formerly Thames Polytechnic)to provide a whole Prof M C E. van Dam-Mieras library of advanced level fle rof w. H. de jeu exible learning Prof ]. de vries

一、增量调制系统的抗噪声性能 在△M系统中同样存在两类噪声,即量化噪声和信道加性噪声。由于这两类 噪声是互不相关的,可以分别讨论。 a)量化信噪功率比 由于在实际应用中都是防止工作到过载区域,因此这里仅考虑一般量化噪 声

3.1矩阵的秩 1.子式:在An中,选取k行与k列,位于交叉处的k2个数按照原来的 相对位置构成k阶行列式,称为A的一个k阶子式,记作D 对于给定的k,不同的k阶子式总共有C个 2.矩阵的秩:在A中,若 (1)有某个r阶子式D,≠0; (2)所有的r+1阶子式D+1=0(如果有r+1阶子式的话) 称A的秩为r,记作 rankA=r,或者r(A)r.规定:rank0=0 性质:(1) rankA min{m,n}

Lecture 2 Differential geometry of curves 2.1 Definition of curves 2.1.1 Plane curves Implicit curves f(, y)=0 Example:x2+y2=a2 It is difficult to trace implicit curves It is easy to check if a point lies on the curve Multi-valued and closed curves can be represented

3.1.2 A general uniqueness theorem The key issue for uniqueness of solutions turns out to be the maximal slope of a=a(a) to guarantee uniqueness on time interval T=[to, t,, it is sufficient to require existence of a constant M such that

第一章概述 1.1概述 一、国、内外水泥路面发展的基本概况 1.水泥路面发展简史 最早: a公元前1世纪,罗马人采用火山灰作胶凝剂,砾石为集料修筑建筑、水利、港口等工 程。 b秦汉,中国人开始用熟糯米浆和石灰作胶凝材料修筑地坪、城墙、墓穴(长城和宋代 古墓的考古发现 c.1824年10月17日,英国工匠 leads和 Aspdin取得波特兰水泥(portland cement)发明 专利。 d.1865年,英国修筑第一条水泥路面。 e.1914年,德国人 Friedrich修建了水泥路面的汽车专用城市道路。 f.1924年,法国人 Daniel Boatest在法国43号公路上铺筑18cm厚,10—20m接缝的碾压混 凝土路面

Ⅱ. Listening skills Identifying prices M: I want two correction pens and a notebook. How much are they? W: $1.95 for each correction pen. $5.00 for the notebook Q: How much does the man have to pay? 2. W: Ooh, it's only $9.8. I bet Jane would love this blue vase. Flowers are really her thing

Uint8 Ⅱ. Listening skills Listening for Rents or Charges 1. M: Look at this ad! \ One bedroom apartment, with kitchen and bathroom. \ It's close to our school, and the price is only $250 a month W: But I want an apartment at least $50 cheaper Q: What is the highest rent the woman is willing to pay? B)$200

Uinta I. Basic listening practice 1. Script M: Did you pick up the paper for me today? i really want to check the job vacancies W: I know, it's over there. There's not much happen though. I had a look already Maybe you should look on the Net instead