萘乙酸处理葡萄苗木根系的效应

1994～2000年对萘乙酸(NAA)处理葡萄(玫瑰香)苗木根系的促根作用、生理反应、高质量浓度下促进皮层组织异常生长的机制进行了探讨。结果表明，100mg／L NAA可有效增加葡萄根量和促进新根生长；促进根皮内蛋白质水解，新根内蛋白质含量增加；高质量浓度的NAA(800mg／L)诱使葡萄根系皮层异常生长，表现为皮层组织松软肿胀，含水量显著增加，离子外渗显著增多，组织液质量浓度明显降低；通过切片观察，高质量浓度的NAA处理的葡萄根皮组织异常分裂而膨胀，最终解体。     

好玩的乐乐圈

将两根直径约2cm、长约50cm的塑料管，分别用一小段木头从两头对接起来，木头上抹上白胶，形成两个圈，并用彩色即时贴进行装饰。圈与圈之问用长约50cm的扁松紧带连接，乐乐圈就做好了。     

自动变圆

小朋友,用一根粗棉线围成一个圈,放在水中,你有办法使这个圈变圆吗？我们可以这样做：取1根火柴,一端粘上一些肥皂,插进棉线圈中,棉线圈立刻自动地胀成圆形,好像是用圆规画出来的一样。这是为什么呢？因为肥皂能够破坏水的表面张力。     

绿色的课堂

“同学们，我们手拉手，围成一个圈。”郝冰拿出一根长长的绳子。     

考考你们的智力

巧修马圈图中是一个用13根木料修筑的马圈,里面可以分圈6匹马,每一格圈着一匹马。因风雨侵蚀,马圈中有一根木料腐朽,不能使用了。     

"一木"激起"千层浪"--"梯形的面积计算"教学一例

在小学数学教材第九册“梯形的面积计算”一节中，有这样一道习 题：“我们经常见到圆木、钢管等堆成像图1的形状，通常用下面的算法求总根数：(顶层的 根数＋底层的根数)×层数÷2，想一想这是什么道理，并算出图中圆木的总根数。”有位教师在指导学生练习时，首先问学生：“这些圆木堆成的横截面，近似于什么形状” ?(生：梯形)“结合梯形面积公式，想一想，你能用较快的方法算出圆木的总根数吗?”[生 ：(顶层的根数＋底层的根数)×层数÷2]。这样图1的总根数很快就可以算出来了。教师很高兴地表扬学生：“真不错，我们以后就要这样，运用…     

一发大师

一发大师,就是只有一根头发的武功大师。瞧他,光秃秃的脑袋像剥了壳的鸡蛋一样圆溜溜,而在脑袋的正中央,长着一根头发,别看只有一根,可这一根头发很长很长,足以围着他的脑袋绕九千九百九十九圈。因此,尽管他只有一根头发,但当他将这根头发一圈～圈盘绕在头顶上时,就像扎了一个发髻,甚至像戴了一顶帽子,让人根本就看不出他是秃顶脑袋上只长着一根头发。     

"狐狸是想骗他自己"

[案例描述]这是全市新课程开放日的研讨活动,我上的是《酸的和甜的》一课。课文第一自然段是这样的:葡萄架下,有一只狐狸。他一会儿转来转去,一会儿跳起来摘葡萄,可是一颗也没摘到。于是,他指着架上的葡萄,说:“这葡萄是酸的,不能吃!”“狐狸明明非常想吃葡萄,可他为什么要说这葡萄是酸的呢?”我的这一问题,犹如丢在河里的一颗石子,荡起一阵思考的涟漪,引起了孩子们的热烈讨论。“狐狸自己吃不到葡萄,也不想让人家吃到葡萄,所以他就故意说葡萄是酸的。”快嘴的嘉嘉,说起话来就像放机关枪。“是呀,狐狸很坏的。他怎么也摘不到葡萄,觉得自己吃…     

小狗的葡萄舞会

春天刚到,小狗找来一株葡萄苗,葡萄苗只有两个毛茸茸的小芽苞,连个根也没有。小鸡问:“小狗,你栽的是什么呀,连个根也没有,能活吗?”小狗说:“是葡萄枝,春天栽下去,只要好好照看,会活的,还能结葡萄呢,到时我请你来吃。”小猫看见了问:“小狗,你种的光秃秃的枝条能结出葡萄吗?”小狗说:“会结葡萄的,到时我一定请你吃葡萄。”     

趣味实验6则(下)

只进不出的软管材料:软管、漏斗、易拉罐、带橡皮塞的250至500毫升大烧瓶，玻璃管1根，洗脸盆1个，胶管1段，红色水1烧杯。工具:锥子 取一根较长的软管，将它绕在一个圆柱体上在管子的上端插进漏斗，并向里面灌水。这时你会发现漏斗里的水只落下一部分，以后就停止了，管子下端没有一滴水流出来。水往低处流。漏斗里的水位比管子下端高，为什么水流不出来呢?原来，当水流满第1圈时，就有一部分水流向第2圈。当第2圈流满，第1圈的上段同时就出现了一段空的气腔，随着水流向后面的各圈，每圈内都会出现相同的气腔，最后，漏斗处的水压不…     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

Western and Eastern culture differences in commercial field

The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

风的曲线

Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.     

团图为数的图中的闭团贯数

Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.