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121.
味精浓废水生物处理优化工艺 总被引:4,自引:0,他引:4
本文阐述两相厌氧消化法与缺氧—厌氧消化法处理味精浓废水的比较试验.进水为6×10~4mg/L~8×10~4mg/L时,两相厌氧消化法COD去除率为78%,产气率为0.15m~3/kgCOD,CH_4含量为50%.缺氧—厌氧消化法COD去除率为82.2%,产气率为0.23m~3/kgCOD,CH.含量达65%.两种方法均可使出水pH值由3.2上升至7.0以上.氯离子和氨氮的去除不明显.综合上述结果与运行管理的稳定程度均是缺氧——厌氧消化法优于两相厌氧消化法. 相似文献
122.
Gonadal structure and population characteristics of the protogynous goby Coryphopterus glaucofraenum
Protogynous hermaphroditism has been reported in two gobiid species within the genus Coryphopterus, including C. nicholsi from the temperate northeastern Pacific and C. personatus from the Caribbean. In a third species from the Caribbean, C. glaucofraenum, experimental groups were established and gonad structure of experimental individuals (collected off the southwest coast of Puerto Rico between February 1985 and June 1987) was subsequently examined histologically to determine the sexual pattern. Protogyny was confirmed in C. glaucofraenum. Sex change was either initiated or completed, typically by the largest female, in all-female groups held for 10 to 40 d. Ovarian, transitional, and testis structure were similar to that of C. nicholsi and C. personatus. No preformed testicular tissue was evident in the ovary proper and ovarian features were not retained in the sex-changed testis beyond the newly transformed stage. Secretory accessory gonadal structures associated with the testis and which develop at the time of sex change arose from precursive tissue masses associated with the ventral portion of the ovarian wall in the region of the common genital sinus. The rapid development and onset of function in these structures, generally preceding that of the associated developing testis, suggest that they may play an important role in sex change events and in advertising new male status. Based on observed similarities of ovarian, transitional and secondary testis structure in three protogynous Coryphopterus species, including one species isolated since the last closing of the American landbridge, it is probable that protogyny is an ancestral condition in this genus. 相似文献
123.
We examined the impact of seven species of mobile mushroom corals (Fungiidae) on the community structure of sheltered reef slopes in terms of their patterns of migration, habitat use and competition with other benthic organisms. On fringing reefs at Eilat, Red Sea, polyps detached at 1 to 6 cm length, and grew to 11–55 cm length. Attached mushroom corals were oriented vertically in reef cavities. Detached corals migrated downward on the reef slope and onto rubble or soft substratum at the reef base, at 29 to 71 cmyr–1. Mobility decreased with corallum size and extent of undersurface ornamentation. In aquaria, small corals righted themselves and migrated up to 6 cm d–1 by nocturnally inflating and pushing their tissues against the substratum. Autonomous coral behavior and storm-generated water motion appeared to account for most fungiid mobility at Eilat. Mushroom corals did not damage each other upon contact, even in multi-species aggregations, but unilaterally damaged non-fungiid scleractinian corals. Their dominance during contact interactions retards overgrowth by larger attached scleractinians, and mobility allows them to colonize soft substrata not accessible to most other reef corals. 相似文献
124.
The sponge Latrunculia magnifica was found to be toxic for fish. A toxin has been isolated from this sponge by organic extraction-column chromatography and thin-layer chromatography. Several chemical properties of the toxin were determined by spectroscopic analysis. Toxicity tests were performed on the fish Gambusia affinis. In vitro experiments showed the toxin to be a cholinesterase inhibitor. 相似文献
125.
Investigation into the pressure resistance of 8 intertidal species belonging to the genera, Uca, Sesurma, Talorchestia and Littorina from the Northern Gulf of Mexico and Panama sheds light on the relationships between temperature and hydrostatic-pressure resistance. Generally, increasing temperature increases the pressure required to elicit reversible reactions such as increased activity and tetany, or paralysis, wheroas increasing temperature generally evokes the irreversible response of death (LD50) at a decreasing pressure. Tropical stenotherms tend to be more sensitive to hydrostatic pressure than eurythermal-temperate species at the same or similar temperatures. 相似文献
126.
To develop a method for the determination of photosynthetic pigment species in individual phytoplankton cells, especially natural picophytoplankton cells, the fluorescence spectra of intact cells were studied with cultured phytoplankton. The study was made mainly with phycoerythrin-containing picophytoplankton collected off Japan in 1982 with reference to diatomal species and phycoerythrin-free cyanophycean species. The spectra were measured for cell suspensions with an ordinary spectrofluorometer, and for individual cells with a microscope spectrofluorometer, paying special attention to the effect of cell-fixation. Results indicated that: (1) the cell-fixation with the glutaraldehyde and paraformaldehyde mixture modified phycoerythrin emission from picophytoplankton markedly in its wavelength location and intensity, but (2) the emission from phycocyanin was affected far less, and (3) the emission from chlorophyll a was not altered. However, the phycoerythrin emission modified by the fixation was found to be easily distinguished from other emissions, and kept its intensity high enough for detection with a fluorescence microscope. The fluorescence properties after the fixation were kept unaltered for a long period of time. Based on the results, we propose a simple method for the determination of photosynthetic pigments in individual phytoplankton cells in seas and lakes using fluorescence microscopy. Results of our tests with natural samples of phytoplankton are presented, and problems for further improvement are also discussed. 相似文献
127.
分别研究了纳米TiO2 在主波长为 364nm的汞灯光照下催化氧化i C3H7OH和CH3COCH3水溶液的反应速率 .通过XRD ,TEM ,BET和FT IR PAS对催化剂进行表征 ,粉末的晶型主要为锐钛矿型 .平均粒径在 1 5nm左右 ,比表面积为 1 0 1 0± 0 2m2 ·g- 1 ,FT IR PAS的检测结果表明 ,CH3COCH3是i C3H7OH光催化氧化的中间产物 ,其光催化氧化反应为 :i C3H7OH [O]CH3COCH3[O]CH3COOH[O]…[O]CO2 H2 O 相似文献
128.
直接进样-离子色谱法测定饮用水中痕量溴酸盐 总被引:13,自引:0,他引:13
对直接测定饮用水中痕量溴酸盐的离子色谱方法进行了优化 .选用高容量的碳酸盐选择性离子色谱柱 ,以 7 2mmol·l- 1 Na2 CO3 2mmol·l- 1 NaOH为流动相 ,可消除样品中碳酸盐、次氯酸根和高浓度氯离子的干扰 ,直接进样测定饮用水中 2 μg·l- 1 溴酸盐 ,其检出限为 0 6μg·l- 1 .样品经微波浓缩后 ,对溴酸盐的检出限可降为 0 0 6μg·l- 1 .方法用于北京市饮用水中溴酸盐浓度的测定 ,结果满意 相似文献
129.
S. Kojima S. Ohta T. Yamamoto T. Yamaguchi T. Miura Y. Fujiwara K. Fujikura J. Hashimoto 《Marine Biology》2003,142(4):625-635
The phylogenetic status of Alaysia-like vestimentiferans, which were collected at eight sites in the western Pacific, was analyzed on the basis of the nucleotide sequence of part of a mitochondrial gene for cytochrome oxidase I. The 123 individuals analyzed were tentatively classified into four species, which inhabit, respectively, seep areas off the central part of the Japanese mainland, hydrothermal vent fields in the Mid-Okinawa Trough, hydrothermal vent fields in the southern Okinawa Trough, and both seep and vent sites in the Bismarck Sea. From six additional lamellibrachiid specimens from two sites in the Bismarck Sea, two new tentative species were recognized, namely, one from a seep area off Papua New Guinea and another from the hydrothermal vent field at the DESMOS site in the Manus Basin. Phylogenetic analysis using all available sequences of six vestimentiferan families and Alaysia-like vestimentiferans revealed that vestimentiferans could be divided into three groups, namely, lamellibrachiids, escarpiids, and others, even though the monophyly of the third group was supported by only low bootstrap probabilities. Within the first group, the earliest divergence of a tentative lamellibrachiid species from the DESMOS site was apparent. All Alaysia-like vestimentiferans formed a monophyletic group with Arcovestia ivanovi from the Manus Basin, and it is suggested that this group might be derived from vestimentiferans that are endemic to the hydrothermal sites in the Eastern Pacific Rise. 相似文献
130.
Y. Henmi 《Marine Biology》1989,101(1):53-60
Two behaviorally distinct forms — courtship signal — (Form L and V) of Macrophthalmus japonicus (De Haan) are known. Monthly samples of each form were collected from two areas in Japan: Form L from Amakusa, western Kyushu, between April 1985 and February 1986; Form V from Fukuoka, northern Kyushu, between November 1982 and December 1983. Life-history traits were compared between two populations and discussed. Individuals from the Amakusa population grew more slowly and matured at a smaller size than those from the Fukuoka population. Maturation period and longevity did not differ significantly. In the first year of reproduction, females in the Fukuoka population produced more, and larger broods than those in the Amakusa population and crab mortality was higher in every age group. Egg size did not differ significantly. The major environmental factors — air-temperature, nitrogen content of the surface mud and period of aerial exposure were similar in both areas, and it is suggested that the differences in life-history exhibited by these crabs are genotypic, and perhaps related to their different form. 相似文献