关于Diophantine方程y2=px(x2+2)的一点注记

设p是奇素数,运用初等数论方法证明了:如果P=16k4+1,这里k为正奇数,则方程y2=px(x2+2)无正整数解(x,y).     

中草药添加剂对断奶仔猪抗氧化功能指标的影响

[目的]探讨中草药饲料添加荆对断奶仔猪抗氧化功能的影响,为中草药添加剂的利用及推广提供参考依据.[方法]选用48头体重相近的断奶仔猪,随机分为试验Ⅰ组(对照组)、试验Ⅱ组、试验Ⅲ组和试验Ⅳ组4个组.在饲喂中草药添加剂后第7、第14和第21天分别采取血液进行抗氧化功能指标的测定.[结果]试验IV组的血清超氧化物歧化酶(SOD)活性和谷胱甘肽酶(GSH-Px)活性在整个试验期间高于其他试验组,尤其在第7天时的差异显著或极显著(P<0.05或P<0.01).且GSH-Px活性随日龄的增加呈先降后升的变化;丙二醛(MDA)含量,在第7和第14天时,试验Ⅳ组低于其他组,差异极显著(P<0.01),在第21天时各组间无显著差异;试验Ⅳ组的一氧化氮(NO)含量显著低于其他组(P<0.05),并随着日龄增加,各组的NO含量均呈下降趋势.[结论]中草药添加剂能提高断奶仔猪抗氧化功能.     

一类平面方程的几何意义

根据点P(x0,y0,z0)与椭球面x2/a2+y2/b2+z2/c2=1的三种位置关系,给出平面方程x0x/a+y0y/b2+z0z/c2=1的三种几何意义.     

对普通线性模型进行显著性检验的公式

线性模型可分为两类: (Ⅰ)y=β_1x_1+β_2x_2+…+β_nx_n+ε (Ⅱ)y=β_0+β_1x_1+β_2x_2+…+β_nx-nβ+ε其中ε是随机误差,e-N(0,α~2)。 对模型I进行显著性检验的公式早巳导出了;而对模型I进行显著性检验,现有文献给出的公式只适用于E(y)=0的特殊情况。我们导出了对模型I进行显著性检验的一般公式,它既适用于E(y)=0,又适用于E(y)≠0。     

稀疏矩阵求逆算法及其在微机上的实现

一、前言投入产出模型能够提供的最本质、同时也是最精华的内容之一,就是通过完全消耗系数来精确地测定各产品之间隐存着的数量依存关系。由流量方程的矩阵形式Ax+y=x得出(I-A)x=y,在此依存系数矩阵(I—A)把总产出向量x和商品量y用线性     

关于Diophantine方程y2=px(x2+2)

对于Diophantine方程y2=px(x2+2),这里p为奇素数,证明了:当p=2593时,它有唯一的正整数解(x,y)=(72,31116).     

P204萃取硫酸体系中V(Ⅳ)、Fe(Ⅲ)的分离性能研究

针对传统提钒技术存在的能耗高、污染重、钒回收率低等缺点,提出钛白废酸无焙烧加压酸浸提钒新技术,以该工艺浸出液为研究对象,通过组分优势区域图、正交试验以及单因素试验,探究P204萃取硫酸体系中V(Ⅳ)、Fe(Ⅲ)的分离性能。试验结果表明:当pH小于2时,V(Ⅳ)在水溶液中主要以VO~(2+)形式存在,Fe(Ⅲ)在水溶液中主要以Fe~(3+)形式存在;相比(O/A)是影响V(Ⅳ)、Fe(Ⅲ)萃取率的重要因素;在较优萃取条件下:有机相组成30%P204+10%TBP+60%磺化煤油,温度T=30℃,震荡时间8 min,水相初始pH值为1.6,相比(O/A)为3,V(Ⅳ)的萃取率为61.16%,Fe(Ⅲ)的萃取率为18.87%,钒铁分离系数为6.67。     

双低菜籽粕饲喂生长肥育猪的效果研究

[目的] 研究应用双低菜籽粕代替豆粕饲喂生长育肥猪的效果.[方法] 试验选择长白(♂)与八眉猪(♀)杂交一代母猪,再与长白公猪(♂)杂交所产三元仔猪共60头,随机分4组,即试验I、II、III和IV组,日粮中分别用0、6%、10%和14%的双低菜籽粕取代日粮中的豆粕.[结果] 试验IV组的日增重极显著低于其他3组日增重(P<0.01),而试验I、II和III组之间差异不显著;通过对血液中谷丙转氨酶(ATL)、谷草转氨酶(AST);甲状腺激素(TSH)、甲状腺素(T4)和三碘甲腺原氨酸(T3)指标测定,各试验组间差异不显著.[结论] 选用10%双低菜籽粕取代豆粕蛋白饲粮饲喂生长育肥猪效果最好.     

预测冬季不同结构大棚内气象要素值的不同数学模型比较研究

[目的]为有效调节大棚内的光照、气温和湿度提供理论依据.[方法]对3种常见结构塑料大棚内外150 cm的冬季光照、气温和湿度等气象要素进行对比观测、分析,建立预测不同结构大棚气象要素值的多种数学模型.[结果]单栋塑料大棚的光照预测模型以多项式y=-0.000 6x3+0.002 9x2+0.740 4x+0.079 9最为确切,气温预测模型以乘幕y =0.759 3x1.1554最为确切,相对湿度预测模型以多项式y =0.000 00 03x5-0.000 1x4+0.013 1 x3-0.873 2x2+29.823-347.99最为确切;3连栋塑料大棚的光照预测模型以多项式y=-0.000 5x2+0.470 61x-0.015最为确切,气温预测模型以指数函数y=4.662 9e0.089x最为确切,相对湿度预测模型以多项式y=-0.0004x3+0.0136x2+0.205 1x +35.056最为确切;6连栋塑料大棚的光照预测模型以直线y =0.399 6x+0.0536,最为确切,气温预测模型以指数函数y=4.622 7e0.897x最为确切,相对湿度预测模型以多项式y =-0.000 08x3+0.089x2+0.645 9x+21.191最为确切.[结论]建立了冬季以棚外气象要紊值预测不同结构大棚内气象要素值的数学模型.     

双低菜籽粕在断奶仔猪日粮中的适宜添加量研究

[目的] 探讨断奶仔猪日粮中双低菜籽粕的适宜添加量.[方法]选取长白(♂)与八眉猪(♀)杂交一代母猪与长白(♂)杂交所产三元杂交仔猪48头,随机分为4组,12头/组,预饲期5 d,然后进行28 d饲喂试验.第1、第2和第3组饲粮中双低菜籽粕的添加量分别为5%,7%和9%,第4组为对照组,不添加双低菜籽粕,平衡日粮中的消化能.[结果] Ⅱ 组断奶仔猪平均日增重最高;第7天与Ⅲ组,第14天和第21天与Ⅲ、Ⅳ组,第28天与其他3组均差异显著(P<0.05).[结论]双低菜籽粕含量为7%时增重效果最好.     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of rates of infection of two methods of emergency ventricular drainage

The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.     

浅析《野草》的版画特征

鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".     

四辊破碎机车刀架的改造

针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。     

Quality of life of relatives of mental patients

Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined.     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.