温度胁迫对辣椒部分生理特性的影响

对15个辣椒品种进行高、低温胁迫,结果表明:高、低温胁迫其叶片的电导率无明显变化;可溶性糖、脯氨酸和丙二醛含量以及根系活力品种之间均存在极显著差异.其中经高、低温胁迫辣椒叶片中可溶性糖、脯氨酸含量大幅度提高,丙二醛含量明显下降,根系活力增强的品种,其耐热或抗寒能力强.综合评判表明耐寒性较强的品种有:苏椒五号,南早x6,A×1,A×W,y×1;耐热性较强的品种有:皖椒四号,A×2,A×1,x×11,x×2;既耐热又耐寒的品种有:x×2,A×1.     

质数的另一个特征

例题52=24×1 172=24×2 1112=24×5 1132=24×7 1……从以上例题可以看出,某些数的平方数都是24的整倍数多1,且这些数都是质数。是不是所有质数都具有这个特征呢?下面我们来证明一下。我们用A表示质数,n表示整数。则有A2=24n 1证明:根据A2=24n 1推导,A2-1=24n(A-1)×(A 1)=24n     

质数的另一个特征

例题52=24×1 172=24×2 1112=24×5 1132=24×7 1……从以上例题可以看出,某些数的平方数都是24的整倍数多1,且这些数都是质数。是不是所有质数都具有这个特征呢?下面,我们来证明一下。我们用A表示质数,n表示整数,则有A2=24n 1。证明:根据A2=24n 1推导A2-1=24n(A-1)×(A 1)=24n从以上例题可以看出,某些数的平方数都是24的整倍数多1,且这些数都是质数。是不是所有质数都具有这个特征呢?下面,我们来证明一下。我们用A表示质数,n表示整数,则有A2=24n 1。证明:根据A2=24n 1推导A2-1=24n(A-1)×(A 1)=24n因为(A-1)、A、(A 1)是三个连续自…     

迎新年 解趣题

1. 计算1/1×3 1/3×5 1/5×7 …… 1/2001×2003 1/2003×2005. 2.己知A=2004/2005-2003/2004,B=2003/2004-2002/2003,C=1/2004-1/2005,试比较A、B、C的大小.     

行列式的降阶定理妙用两则

《线性代数》中的行列式的降阶定理是:定理设A、D分别为n×n、m×m矩阵,B、C分别为n×m、m×n矩阵,若A、D可逆,则|A B C D|=|A||D-CA~(-1)B|     

新编数学试题赏析

今年1月25日,盐城市组织了全市省级实验 小学部分年级、部分学科的教学质量调研, 下面从四年级数学苏教版、人教版、景山版不同版本 的试卷中,选取几道新编试题并作简要分析,以求教 于同行。 试题一:如果A=21×89,B=22×88,要比较A和B 的大小,除了可以先算出它们的结果再比较外,还可 以用学过的运算定律帮助思考(在□中填数,在○中 填符号)。 因为:A=21×89 =21×(88 1) =21×88 □×1 B=22×88 =(21 1)×88 =21×88 1×□ 所以:A○B 简析:本题知识上主要考查学生运算定律的学习     

乘积格蕴涵代数的理想

在乘积格蕴涵代数中研究乘积格蕴涵代数的理想,乘积格蕴涵代数的各种理想之间的关系,证明了A×B是L1×L2的理想(素理想)当且仅当A,B分别是L1和L2的理想(素理想),两条Lukasiewicz链Lm和Ln的直积Lm×Ln只有{a1}×Ln和Lm×{b1}两个素理想.     

枯草芽孢杆菌抑制水体微生物及对克氏原螯虾生存状态的影响

通过设计不同浓度枯草芽孢杆菌的投放梯度,检测水体中大肠菌群、金黄色葡萄球菌数量的变化以及对克氏原螯虾的体重增长率、存活率、抗逆性的影响。设计一个对照组（ A0）,五个实验组（ A1、A2、A3、A4、A5）,投放浓度分别为1×102、1×103、1×104、1×105、1×106 cfu／mL。结果表明,投放了枯草芽孢杆菌的实验组与空白组相比,能明显提高克氏原螯虾的体重增长率（比对照组提高38．1％）、存活率（比对照组提高25．5％）,以及具备一定的抗逆性（比对照组提高36．6％）;并且证明枯草芽孢杆菌能抑制水体中的大肠菌群和金黄色葡萄球菌等有害致病菌,一定程度上提高了克氏原螯虾食用的安全性。实验结果分析表明枯草芽孢杆菌的最佳投放浓度为1×104 cfu／mL。     

乘积格蕴涵代数的理想

在乘积格蕴涵代数中研究乘积格蕴涵代数的理想,乘积格蕴涵代数的各种理想之间的关系,证明了A×B是L1×L2的理想（素理想）当且仅当A,B分别是L1和L2的理想（素理想）,两条Lukasiew icz链Lm和Ln的直积Lm×Ln只有{a1}×Ln和Lm×{b1}两个素理想.     

一个新的三角不等式

在△ABC中,成立以下不等式: cos A(cos B cos C)≤(2×6~(1/2))/9,(1) sin A(sin B sin C)≤(8×3~(1/2))/9,(2) sin A(cos B cos C)≤(8×3~(1/2))/9.(3)     

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,     

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?     

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.     

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.