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More Rural Research is Needed 1.Agricultural research funding is vital if the world is to feed itself better than it does now.Dr.Tony Fischer, crop scientist, said demand was growing at 2.5% per year, but with modern technologies and the development of new ones, the world should be able to stay ahead. 2.'The global decline in investment in international agricultural research must be reversed if significant.progress is to be made towards reducing malnutrition(营养不良)and poverty,' he said. 3.Research is needed to solve food production, land degradation(贫瘠化)and environmental problem.Secure local food supplies led to economic growth which, in turn, slowed population growth.Dr.Fischer painted a picture of the world's ability to feed itself in the first 25 years of the new century, when the world's population is expected to rise from 5.8 to 8 billion.He said that things will probably hold or improve but there'll still be a lot of hungry people.The biggest concentration of poor and hungry people would be :in subSaharan Africa and southern Asia in 2020, similar to the current pattern.If there is any change, a slight improvement will be seen in southern Asia, but not in subSaharan Africa.The major improvement will be in East Asia, South America and Southeastern Asia. 4.The developing world was investing about 0.5%, or $8 billion a year, of its agricultural gross domestic product (GDP) on research, and the developed world was spending 2.5 % of its GDP.Dr.Fisher said more was needed from all countries. 5.He said crop research could produce technologies, that spread across many countries, such as wheat, production research having spin-offs for Mexico, China or India. 6.'Technologies still need to be refined for the local conditions but a lot of the strategic research can have global application, so that money can be used very efficiently,' Dr.Fischer said. 7.Yields of rice, wheat and maize(玉米)have grown impressively in the past 30 years,especially in developing .countries.For example, maize production rose from 2 to 8 tonnes per hectare(公顷)between 1950 and 1995.But technologies driving this growth, such as high-yield varieties, fertilizers and irrigation, were becoming exhausted.'If you want to save the land for non-agricultural activities, for forests and wildlife, you're going to have to increase yield,' Dr.Fischer said.
A.
The Same or Improved Food Supply Situation in 2020
B.
Research Focus on Increased Yield C More Research Funding Needed D.Local Situations Analyzed E.Increase in Investment on Agricultural Research F.Sustained Development of Modern Technologies 第 23 题 Paragraph 1____.
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举一反三
【单选题】关于 黑茶渥堆的实质,主要有三种学说:一是酶的作用学说;二是( );三是湿热作用学说。
A.
糖类分解学说
B.
氨基酸分解学说
C.
叶绿素分解学说
D.
微生物作用学说
【简答题】晶闸管-电动机调速系统(简称V-M系统),图中VT是________,通过调节触发装置 GT 的________来移动________即可改变整流电压Udo ,从而实现平滑调速。
【简答题】晶闸管可控整流电路输出电压的改变是通过调节 来实现的。
【单选题】UDP的检验和检验UDP数据报的( )。
A.
数据部分
B.
首部
C.
首部和数据部分
D.
伪首部
【单选题】溃疡患者服用制酸剂宜在
A.
饭后1~2小时
B.
饭前1~2小时
C.
每日清晨一次
D.
两餐之间
E.
进餐时与食物同服
【单选题】晶闸管整流电路输出电压值的改变是通过()来实现的。
A.
调节触发电压相位
B.
调节触发电压大小
C.
调节阳极电压大小
【单选题】晶闸管整流是通过改变()来实现调压的。
A.
交流电压的大小
B.
触发角
C.
导通角
D.
通电时间
【单选题】晶闸管整流电路输出电压的改变是通过 ( ) 来实现的。
A.
调节触发电压相位
B.
调节触发电压大小
C.
调节阳极电压大小
D.
调节负载的大小
【单选题】下列不属于微机只要性能指标的是()
A.
字长
B.
内存容量
C.
软件数量
D.
主频
【多选题】黑素的生物学作用主要有( )
A.
防止紫外线对皮肤损伤
B.
防止弹性纤维变性老化
C.
黑素可促进皮肤中维生素D的合成
D.
降低皮肤癌的发生率
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