土壤缓冲性的概念及其产生原因?

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问题:

土壤缓冲性的概念及其产生原因?

考点:土壤肥料学复合肥料复合肥料题库
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口对口人工呼吸时,吹气送气的时间为(),使胸廓起伏。

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如图为路口交通指示灯的示意图.指示灯可以通过不同颜色灯光的变化指挥车辆和行人的交通行为.据你对交通指示灯的了解可以推断(  )

A.红灯、黄灯、绿灯是串联的

B.红灯、黄灯、绿灯是并联的

C.红灯与黄灯并联后再与绿灯串联

D.绿灯与黄灯并联后再与红灯串联

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如图所示,长为L的轻绳一端系于固定点O,另一端系一质量为m的小球,将小球从O点正下方

L
4
处,以水平初速度向右抛出,经一定时间绳被拉直,以后小球将以O为支点在竖直平面内摆动.已知绳刚被拉直时,绳与竖直方向成60°角.求:

(1)小球水平抛出的初速度v0

(2)在绳被拉紧的瞬间,支点O受到的冲量.(忽略绳被拉紧的瞬间小球的重力冲量)

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     When Mary Moore began her high school in 1951,her mother told her,"Be sure and take a t

yping course so when this show business thing doesn't work out,you'll have something to rely on."

Mary responded in typical teenage fashion.From that moment on,"the very last thing I ever

thought about doing was taking a typing course," she recalls.

     The show business thing worked out,of course.In her career,Mary won many awards.Only

recently,when she began to write Growing Up Again,did she regret ignoring her mom," I don't

know how to use a computer," she admits.

     Unlike her 1995 autobiography,After All, her second book is less about life as an award

winning actress and more about living with diabetes (糖尿病).All the money from the book is

intended for the Juvenile Diabetes Research Foundation (JDRF),an organization she serves as

international chairman."I felt there was a need for a book like this," she says." I didn't want to

lecture,but I wanted other diabetics to know that things get better when we're self?controlled

and do our part in managing the disease."

     But she hasn't always practiced what she teaches.In her book,she describes that awful day,

almost 40 years ago,when she received two pieces of life changing news.First,she had lost the

baby she was carrying,and second,tests showed that she had diabetes.In a childlike act,she left

the hospital and treated herself to a box of doughnuts (甜甜圈).Years would pass before she

realized she had to grow up again-and take control of her diabetes,not let it control her.Only

then did she kick her three pack a day cigarette habit,overcome her addiction to alcohol,and

begin to follow a balanced diet.

     Although her disease has affected her eyesight and forced her to the sidelines of the dance

floor,she refuses to fall into self pity."Everybody on earth can ask,'why me' about something

or other," she insists."It doesn't do any good.No one is immune (免疫的) to heartache,pain,

and disappointments.Sometimes we can make things better by helping others.I've come to

realize the importance of that as I've grown up this second time.I want to speak out and be as

helpful as I can be."

1.Why did Mary feel regretful? _____

A.She didn't achieve her ambition.

B.She didn't take care of her mother.

C.She didn't complete her high school.

D.She didn't follow her mother's advice.

2.We can know that before 1995 Mary. _____

A.had two books published

B.received many career awards

C.knew how to use a computer

D.supported the JDRF by writing

3.Mary's second book Growing Up Again is mainly about her. _____

A.living with diabetes

B.successful show business

C.service for an organization

D.remembrance of her mother

4.When Mary received the life?changing news,she. _____

A.lost control of herself

B.began a balanced diet

C.tried to get a treatment

D.behaved in an adult way

5.What can we know from the last paragraph? _____

A.Mary feels pity for herself.

B.Mary has recovered from her disease.

C.Mary wants to help others as much as possible.

D.Mary determines to go back to the dance floor.

题型:问答题 简答题

ZXMP M800可接入如下业务()

A、SDH业务,包括STM-1/4/16/64

B、SONET业务,包括OC-3/12/48/192

C、ATM业务或POS业务,包括VC4、VC4-4c、VC4-16c

D、以太网业务,包括100Mbit/s、GbE

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