Some observations on the temporal variations of size of copepods and some answers to questions on their biology. [Translation from: Internationale Revue der Gesamten Hydrobiologie und Hydrographie 17 99-114, 1927.]

Until now observations on the temporal variation of size of freshwater copepods have not provided much information. Other observers only mention in passing this or that phenomenon from which it is possible to deduct termporal variations. In this study Cyclops strenuus s.l., a freshwater species of fairly wide distribution, is studied in two water bodies. The author studies the systematic, placing of inhabitants described as C. strenuus Fischer in both locations, their annual life cycle, and their annual size variations.

A marked effect of water snails on small crustaceans. [Translation from: Anz.Ost.Akad.Wiss 10, 95-99, 1952. ]

Cases of mutual exclusion of two species of organisms in nature are known in large numbers. In the majority, they make different demands on the environ- ment which makes co-occurrence impossible. Less frequent are those cases in which a definite activity of one species prevents the occurrence of the other in the same region. An experiment was carried out n order to establish if Chydorus sphaericus can co-occur with water-snails. It emerged that a substance soluble in water which is given off by snails is responsible for the negative effect on small crustacea.

Determination of dissolved oxygen in water with leukoberbelin-blue I. A quick Winkler method. [Translation from: Z.analyt.Chem. 262 97-99, 1972.]

The reaction of Mn(II) with water-dissolved oxygen, to a higher manganese hydroxide in an alkaline medium, as with the longstanding classic Winkler method, is the first step in the method described here. The assumption for faultless results by the conventional and modified Winkler method is clean water, which contains no organic substances by Mn(III) or Mn(IV). In many cases, however, eg. in river and lake-water tests, it can be seen with the naked eye that after some time the originally brown-coloured precipitate of manganese hydroxide becomes more and more colourless. Oxygen content was analysed in the water samples and evaluated by raising the amount of the leuko-base and giving the corresponding dilution of the colouring matter solution formed still higher oxygen contents can be measured.

Biology of the amphipod Gammarus pulex L. in water-bodies of the Leningrad district, and its piscicultural importance [Translation from: Trudy Vsesoyuznogo Gidrobiologicheskogo Obshchestva 7 99-122, 1956]

Observations and laboratory experiments are summarised that examine the widely discussed issue of what Gammarus pulex feeds on. On the basis of the observations of the authors and data from the literature it can be noted that G. pulex belongs to the omnivorous organisms, but, depending on the conditions of subsistence, in its rations either plant or animal food can predominate.

Crystal growth and optical properties of Gd1.99-xYxCe.0.01SiO5 single crystals

Gd1.99-xYxCe0.01SiO5 (Ce:GYSO) crystals (x = 0, 0.0995, 0.199) have been grown by the Czochralski (Cz) method. Crystal structure and the distribution coefficients of Ce have been determined for all three crystals. Spectroscopic measurements indicate that optical transmittance and luminescence intensity of Gd1.99-xYxCe0.01SiO5 (x = 0.0995, 0.199) crystals are Substantially higher than those of Ce:Gd2SiO5 (Ce:GSO), especially at x = 0.0995, which makes them good candidate materials for scintillation applications. The particularly important result is that the alloyed Ce:GYSO crystals can be grown easily by the Cz method and, unlike Ce:GSO, they do not undergo cleavage during the growth process or subsequent mechanical treatment. (c) 2005 Elsevier B.V. All rights reserved.

Enhancement of ferromagnetic properties in In1.99Co0.01O3 by additional Cu doping

This paper reports room-temperature ferromagnetism in Co- and Cu-doped In2O3 samples synthesized by a solid-state reaction method. Structure and composition analyses revealed that Co and Cu were incorporated into the In2O3 lattices. Photoluminescence measurement revealed an additional emission at 520 urn from these doped samples. The magnetic measurement showed that additional Cu doping greatly enhanced the ferromagnetism of In1.99Co0.01O3 bulk samples. The implication of the effects of additional Cu doping is also discussed. (c) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

National Agricultural Research Organisation. Fisheries Resources Research Institute Annual Report 1998/99

The annual report presents research programs carried out by the institute during the reporting period. FIRRI has the mandate is to promote, undertake and coordinate all aspects of research in fisheries, fish production systems and the water environment, aquaculture and socio-economics while conserving the natural resource.

鱼苗养成夏花的成活率高达98.99％—水生生物研究所初步试验成功新的饲养方法

<正> 鱼苗养成夏花的成活率,过去一般只有50%左右,有些低的还不到10%。这是发展淡水养鱼生产的巨大障碍之一。湖北省每年从江中捕获鱼苗很多,留养的数量也很大,但每年大湖放养的鱼种,还要向外省购进。这便说明提高鱼苗养成夏花、养咸鱼种的成活率的重要意义了。我所鱼病学组的工作者,在党的支持下,进行了提高鱼苗养成夏花成活率的饲养方法的试验,已获得良好

Microcalorimetric investigation of the effect of manganese(II) on the growth of Tetrahymena shanghaiensis S(1)99

The heat output of and the effect of manganese (II) on Tetrahymena shanghaiensis S(1)99 growth metabolism has been determined by means of a LKB-2277 BioActivity monitor. Different concentrations of manganese(II) ions have different effects on the growth of T. shanghaiensis. At low concentrations (0-40 mug/mL) culture growth is promoted, whereas high concentrations (60-800 mug/mL) slow growth. Furthermore, concentrations of 1200 mug/mL or greater stop the growth of this protozooa completely.

浅析旱作农业技术在黄土高原退耕还林(草)之后的作用——为朱总理’99,8,7讲话而作

针对朱基总理 1 999年 8月 7日讲话精神和旱农技术在特殊的自然条件和社会条件下为了良化农田生态环境和持续增产所采取的一整套用地与养地相结合的技术体系。文章着重的分析了培肥地力、轮作倒茬、化学技术、选育品种、节水、立体种植、地膜覆盖、水土保持耕作法八种技术 ,充分利用光、热、水、气、土、肥资源而取得明显的社会效益、经济效益和生态效益 ,剖析了旱作技术在农业持续、稳定、健康发展中的作用和改善农业生态环境的显著地位 ,供同类地区的决策者和研究者借鉴

~(99)Tc~m-明胶的制备和生物分布

为考察明胶静脉注射后在机体内的吸收及分布情况,用~(99)Tc~m对明胶进行整体标记,然后将标记物~(99)Tc~m-明胶静脉注射于小鼠和家兔体内,检测不同时间后标记物的生物分布.结果表明,明胶可以被~(99)Tc~m所标记,且标记产物~(99)Tc~m-明胶放化纯大于95%;小鼠体内分布显示其具有较高肾摄取率,5 min时小鼠肾的摄取率达到29.36%/g,20 min时可以达到66.88%/g;家兔双肾显像清晰.说明~(99)Tc~m-明胶具有特异性肾分布的特点.