韶关市区饮用地表水源地水质分析

采用GB38388-2002作为评价标准和实测资料,对韶关市区主要地表达饮用水源地水质的年平均值随年份变化趋势进行分析,较为全面地阐述了水质现状,变化趋势及成因,得出水源地未达到2类保护目标和砷已对水源地构成安全隐患的结论.提出保护好水源地的一些建议,为当地政府决策部门的决策提供依据,同时也让更多的市民从中了解当地水源地的情况,提高市民对保护用水源地重要性的认识,达成人人参与共同保护的共识.     

超长引水隧洞水电站大波动过渡过

通过数值计算的方法，以锦屏二级水电站为例分析了超长引水隧洞水电站在大波动过渡过程方面的特点。计算结果表明:超长引水隧洞水电站由于调压室波动周期长、衰减慢、振幅大，因此一般情况下其上游管线最大、最小压力分布均受到上游调压室最高、最低涌浪的控制；同时对于该类水电站来说需要考虑波动叠加所带来的不利影响。     

Natural infection with two genotypes of Cryptosporidium in red squirrels (Sciurus vulgaris) in Italy

We investigated the genotypes of Cryptosporidium infecting red squirrels (Sciurus vulgaris L.) in two areas of the Western Alps in Italy. Examination of 141 faecal samples from 70 red squirrels revealed oocysts of Cryptosporidium in 17 animals (24.3%). Based on 18S rRNA gene sequencing, two genotypes of Cryptosporidium species were found: 15 squirrels were positive for the Cryptosporidium ferret genotype and 2 for the Cryptosporidium chipmunk genotype I. The occurrence and intensity of Cryptosporidium infection did not differ between the study areas or sex. More than 85% of the positive animals were adults; however no difference was found between Cryptosporidium infection in the juvenile and adult age groups. Oocysts of the Cryptosporidium ferret genotype measured 5.5 +/- 0.3 x 5.2 +/- 0.2 microm (shape index 1.06) and the Cryptosporidium chipmunk genotype I 5.8 +/- 0.3 x 5.4 +/- 0.3 microm (shape index 1.07). Neonatal and adult CD1 and BABL/c mice inoculated with 1 x 10(3) fresh oocysts of both genotypes did not produce detectable infection.     

小清河干流济南城区段主河槽河岸

以具体工程小清河济南城区段为例,研究水库型河道在确定主河槽河岸设计高程应考虑的影响因素。提出对于既有景观功能又有防洪要求的河道,主河槽河岸设计高程应分汛期与非汛期进行考虑,综合防洪要求及景观效果确定所需高程。     

The effect of Rhizobium spp. inoculation on seed quality of bean in Turkey

Rhizobium spp. (local isolate) was used to inoculate three bean (Phaseolus vulgaris L.) varieties; Akman 98, G?ynük 98 and Sehirali 90, in a factorial field experiment. The objective of the experiment was to study effect of inoculation on seed yield, protein range, seed weight, non-soaker capacity and hydration index. Rhizobium spp. inoculation and nitrogen fertilizer significantly increased characters tested. This study revealed that inoculation with Rhizobium spp. improved seed quality.     

从十六世纪到十九世纪的油画中研究栽培植物的历史

十六世纪到十九世纪产生于佛兰德和荷兰的油画是研究栽培植物发展的有用资料,他们显示了那一时期的文献所未描绘或者只是粗略地提及的许多蔬菜、水果和观赏植物。研究作物历史有多方面的资料,如从驯育到今天仍然生活和被保存的植物材料;在植物学和农业文献中的描述;插图等等。那些高度驯化的植物原始的和半驯化阶段的活材料极为稀少,人们可能偶尔在一些未充分发展农业的地区发现。随着世界范围内的许多     

滴头堵塞诱发过程及其可控方法的

滴头作为滴灌系统的关键部件，其性能的优劣直接反映了整个滴灌系统寿命、节水性及灌水的均匀性。流道的堵塞问题一直是抑止滴灌技术发展的主要瓶颈，而随着再生水滴灌、微咸水滴灌、雨水滴灌等技术的迅速发展，对滴灌系统抗堵塞能力也提出了更高的要求，堵塞问题成为了滴灌技术研究的热点。分析了滴头堵塞诱发的研究现状，就流道内的堵塞诱发因素、诱发过程、生物膜的存在对于堵塞的影响、流道内生物膜生物、物理特征以及控制方法等几个问题进行了探讨，并结合现代分子生物学技术及测量技术提出了有关流道内生物膜微生态多样性、生长特征等问题研究的发展方向。     

非洲电力发展障碍和小水电发展前

非洲不但有十分丰富的天然气、煤等矿物能源，太阳能和风能等,而且有十分丰富的水电资源，但这些丰富的可再生能源并未得到有效利用。本文通过非洲的电力发展状况和农村电气化发展现状分析，探讨了非洲地区电力发展的障碍，以及非洲农村地区小型水电发展的前景。     

Prevalence and pathogenicity of Cryptosporidium suis in pre- and post-weaned pigs

A total of 4338 faecal samples, 135 of sows, 3368 of pre-weaned and 835 of post-weaned piglets from eight farms in South Bohemia, Czech Republic were collected and examined for Cryptosporidium infection. No sow, but 5.7% pre-weaned and 24.1% post-weaned piglets were positive for Cryptosporidium infection. No relationship was found between diarrhoea and Cryptosporidium infection in any of the different age groups (pre- and post-weaned piglets). Four piglets, which were sporadically shedding cryptosporidia in faeces, were necropsied. Neither clinical signs of diarrhoea nor macroscopical changes were found. Histologically, a moderate infection of cryptosporidia was detected in the glandular epithelium along the large intestine, with predisposition to the ansa centralis of the colon. No inflammatory response in the lamina propria was observed. Cryptosporidia were also commonly found in the glandular epithelium of submucosal lymphoglandular complexes in the colon. Cryptosporidium isolates from all farms were identified as Cryptosporidium suis using molecular markers (SSU rRNA). All of the C. suis strains obtained were larger [6.2 (6.0-6.8) x 5.5 (5.3-5.7) microm] than any isolate described so far [4.6 (4.4-4.9) x 4.2 (4.0-4.3) microm] and did not appear to be infective for neonatal BALB/c mice.