推广的KdV方程的孤立波解

本文首次正确地给出了推广的KdV方程的孤立波的三阶近似解析解。     

粉锈宁和灭草喹药液的pH值对其在叶面吸收影响的初步研究

本试验研究了药液酸碱度对粉锈宁和灭草喹在蚕豆叶面吸收率的影响。结果表明:①药液酸碱度对粉锈宁的吸收影响不大。②药液 pH 值可以显著地影响蚕豆叶片对灭草喹的吸收:pH 越小,吸收率越高。因而对于弱酸性农药,在作物能够忍受并且药剂本身也稳定的 pH 范围内,使用偏酸的药液可望达到提高其吸收率的目的。     

广东啮虫一新种及圆(虫齿)属的研究((虫齿)目:圆(虫齿)科、外(虫齿)科)

记述了外(虫齿)科 Ectopsocidae 一新种,即广东邻外(虫齿)Ectopsocopsis guangdongensissp.n.;记述了圆(虫齿)属 Psoquilla Hagen,并建立一新组合种 Psoquilla dispar(Verrill)。     

THE DURATION OF THE OESTROUS CYCLE OF EWES AFFECTED WITH CLOVER DISEASE

Oestrous cycles in ewes affected with clover disease were compared with those for control animals at two locations. Significantly fewer diseased ewes were observed in oestrus. There was a significant increase in variability of oestrous cycle duration in the diseased ewes at one location. Some of the cycle irregularities could be related to gross lesions in the internal genitalia. Despite these findings, there was no association between oestrous cycle abnormalities and previous fertility records, suggesting that they are of little consequence to the infertility of clover disease under field conditions.     

石墨炉原子吸收法测定微量锗的方法(简报)

有机锗的抗癌作用已引起人们的关注,用石墨炉原子吸收法测定锗的报道很少,测定锗的困难在于试样中的锗在原子化之前以易挥发的 GeO 形式损失掉了,影响分析准确度。本试验采用在热解石墨管内涂难熔金属层,使石墨管表面性质得到改善并采用镁和钯为改进剂,对降低基体干扰获得了明显效应     

碳酸钙在土壤中对Cu,Pb,Cd形态转化的影响(简报)

采用连续分组的方法,研究碳酸钙含量和 pH 值对 Cu,Pb,Cd 在土壤中的形态转化的影响。供试土壤为暗栗钙土表层(0～20cm):pH(CaCl_2)7.08,有机质2.52%,CaCO_3未检出。分别向土壤中加入 CaCO_3,使其含量为0%,1%,3%,5%,7%,并加入50mg/kgCu,Pb,Cd 的硝酸盐溶液。在25±2℃和相对湿度80%条件下培养。并分别在1d,15d,30d,60d 时采样。     

The bacteriology and serology of ewes inoculated with viable Brucella ovis organisms

A series of 10 farm trials was conducted in which the lambing performance of ewes immunised against polyandroalbumin was compared with that of untreated ewes in the same flock. The trials show that polyandroalbumin treatment is a reliable method of increasing lambing and tailing percentages in New Zealand flocks. An average of 39 extra lambs born per 100 ewes tupped was achieved on farms where ewes were given two treatments about four weeks apart and rams were introduced 18–26 days after the second dose. On farms where rams were introduced less than 12 days after this booster injection an average of 19 extra lambs born per 100 ewes tupped resulted.

On farms where rams were introduced at 18–26 days post booster injection an average of 35 extra lambs were tailed for every 100 ewes tupped.

The response for immunization increased in direct relation to the liveweight of the ewes at tupping.     

A study of the pattern of staphylococcal contamination of the udders of cows in a dairy herd

Abstract

Extract

The results of the 1965–6 New Zealand national mastitis survey (Anon., 1967 Anon Ann. Rep. Res. Div. N.Z. Dept. Agric. 1966–67 1967 77 78  [Google Scholar]) indicated that β-haemolytic staphylococci were the most common bacteria isolated from the milk of dairy cows. Effective control of β-haemolytic stapyhlococci on a national scaledepends ultimately upon an understanding of population changes of this organism within the cow and within the herd.     

Effect of staphylococcal contamination of the bovine udder on milk yield

Zinc sulphate was added to the drinking water of Angus cows and calves grazing an area considered marginal for copper nutrition of cattle. Mean daily intakes of approximately 12–15 mg Zn/kg live-weight further depressed already low plasma copper concentrations to levels considered to indicate copper deficiency. The plasma copper concentrations in untreated animals increased during the trial indicating adequate copper intakes during this period, but the high zinc intakes of treated animals prevented this seasonal rise. Injection of copper glycinate (0.24 g/animal) alleviated the depression of plasma copper associated with the high zinc intakes. The zinc supplements had little effect on plasma zinc concentrations.     

The effect of staphylococcal antigen on the output of cells from the popliteal lymph node of immunized sheep

Serum samples collected from dogs routinely presented at a clinic between June 1974 and October 1980 were tested for the presence of haemagglutination inhibition (HI) titres to canine parvovirus. The first positive titre (> 1:320) was demonstrated in serum collected in October 1979. The first confirmed clinical case of canine parvovirus enteritis was diagnosed by the authors in July 1979.

In addition, between 1st December 1980 and 1st March 1981, serum samples were collected from 106 healthy dogs which were presented for canine parvovirus vaccination for the first time. Twenty-four dogs (approx. 23%) showed HI titres > 1:320 indicating probable previous canine parvovirus infection. Therefore approx. 80% of dogs in the clinic area were at risk at that time and vaccination should have protected them from infection.