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Effects of temperature and irradiance on early development of Chondrus ocellatus Holm (Gigartinaceae,Rhodophyta) 被引量:4
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作者 李晓 赵鹏 +3 位作者 王高歌 李大鹏 王继成 段德麟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第3期508-513,共6页
Chondrus is a type of commercially produced red seaweed that widely used for food and carrageen extraction. Although the natural life history of the alga had been well understood, the factors influencing development o... Chondrus is a type of commercially produced red seaweed that widely used for food and carrageen extraction. Although the natural life history of the alga had been well understood, the factors influencing development of the tetraspore and carpospore remain poorly understood. In the perspective of seedling resources, the regulation of early development is crucial for the seedlillg nursing; therefore, it is necessary to understand the physiological influences during its early development. In this study, we studied the effects of temperature and irradiance on the early development of Chondrus ocellatus Holm under laboratory conditions. The released tetraspores and carpospores were cultivated at different temperatures (10-28℃) and irradiances (10, 60 μmol photons m^-2s^-1) with a photoperiod of 12L: 12D. The results indicate that both tetraspores and carpospores are tolerant to temperatures of 10-25℃, and have the highest relative growth rate at 20℃. Irradiance variances influenced the growth of the discoid crusts, and the influence was more significant with increasing temperature; 60 μmol photons m^-2s^-1 was more suitable than 10 μmol photons m^-2s^-1. The optimum temperature and irradiance for the development of seedlings was 20℃ and 60 μmol photons m^-2s^-1, respectively. 展开更多
关键词 Chondrus ocellatus TEMPERATURE IRRADIANCE early development
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Effect of temperature and photoperiod on maturation of Cephalothrix hongkongiensis(Nemertea: Palaeonemertea)
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作者 李应东 宋肖跃 +2 位作者 张珊珊 朱林 孙世春 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期764-772,共9页
The limited knowledge about the relationships between environmental factors and the maturation and reproductive seasonality of nemerteans is mostly obtained from field studies, and in many cases is conjectural. Few sp... The limited knowledge about the relationships between environmental factors and the maturation and reproductive seasonality of nemerteans is mostly obtained from field studies, and in many cases is conjectural. Few species have been studied under well-controlled laboratory conditions. In this work, the effects of temperature and photoperiod on gonad development and spawning of Cephalothrix hongkongiensis were observed by rearing worms under different temperatures and photoperiods. Worms reared at 4~C and 6~C showed no growth or gonadal development, and all died within 109 days. At 8~C and 12~C, gonads could be seen from 90 days to the termination of the 360-day experiment, but no spawning was observed. Worms maintained at 16, 24, and 28~C showed both gonadal development and spawning, and matured faster at higher temperatures. Under a fixed temperature (16℃), photoperiod did not have any significant impact on maturation and spawning. It is likely that temperature plays a major role in regulating the maturation and reproductive cycle of C. hongkongiensis. 展开更多
关键词 TEMPERATURE PHOTOPERIOD gonad development REPRODUCTION Cephalothrix hongkongiensis NEMERTEA
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Traffic Noise Pollution: Spectra Characteristics and Windows Sound Insulation in Laboratory and Field Measurements 被引量:2
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作者 C. Buratti E. Moretti 《Journal of Environmental Science and Engineering》 2010年第12期28-36,共9页
The traffic spectra influence on indoor noise through windows is evaluated with laboratory and field measurements. Different traffic noise spectra were registered and reproduced, simulating the outdoor traffic conditi... The traffic spectra influence on indoor noise through windows is evaluated with laboratory and field measurements. Different traffic noise spectra were registered and reproduced, simulating the outdoor traffic conditions through different windows. Spectrum adaptation terms for the recorded spectra were different from the ones obtained from the Standards, showing that Normative gives a safe evaluation of the Weighted Sound Insulation Index. In field measurements, the level abatements calculated from the Facade Acoustic Insulation Index corrected with the adaptation terms shows that the ones from the Standard do not give a good approximation, while if the level abatements is calculated using the adaptation terms from the registered spectra, a more reliable approximation is achieved. Furthermore, comparing the level abatements for two windows having both Rw equal to 41 dB, very different values were obtained at different frequencies; therefore to characterize acoustic performances of windows, sound insulation curves are also needed. The correlation between the mean difference between adaptation terms calculated from the standard and the one between abatements obtained with pink noise and the ones obtained with the registered spectra is good, but different for road traffic and trains. In both, the difference diminishes when the difference between the abatements increases. 展开更多
关键词 Traffic noise pollution traffic noise spectra spectrum adaptation terms level abatements
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Industrial Production of Catalyst for Removing Trace Olefins from Aromatics
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作者 Pu Xin Shi Li 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2012年第2期44-49,共6页
A novel additive incorporated into the catalyst for removing trace olefins from aromatics was proposed, and under the laboratory conditions the lifetime of the catalyst was increased from 5 h to 8 h upon specifying th... A novel additive incorporated into the catalyst for removing trace olefins from aromatics was proposed, and under the laboratory conditions the lifetime of the catalyst was increased from 5 h to 8 h upon specifying the conversion of the olefins equating to more than 55% as a criterion. Catalyst production, which was named ROC, has been successfully scaled up from laboratory formulations to commercial scale manufacture and over 100 tons of catalyst had been produced. The superiority in catalytic activity was identified by the evaluation tests of the ROC catalyst based on whatever kind of feedstocks (with their bromine index ranging from 400 mgBr/100g to 1 200 mgBr/100g) being used as the feedstock. The X-ray diffraction patterns had verified that the additive was highly dispersed on the surface of catalyst; the GC-FID analysis results showed that the ROC catalyst could increase the xylene content; the pyridine-FTIR spectroscopic analyses suggested that the additive could increase the amount of the weak L acids, which was the main cause leading to enhancement of the catalyst activity. 展开更多
关键词 OLEFINS AROMATICS industrial production CATALYST
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Verification of Insulation Oil Reclamation by Turbidity and Spetrophotometry Measurements
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作者 Janvier Sylvestre N'cho Issouf Fofana +2 位作者 Abderrahmane Beroual Thomas Aka-Ngnui John Sabau 《Journal of Energy and Power Engineering》 2012年第5期703-712,共10页
Oil reclamation with Fuller's earth is known to have an improved effect on conditioning aged oil. In this paper it is shown that aged oil reclamation effectiveness can be monitored with turbidity and spectrophotometr... Oil reclamation with Fuller's earth is known to have an improved effect on conditioning aged oil. In this paper it is shown that aged oil reclamation effectiveness can be monitored with turbidity and spectrophotometry measurements. These low cost testing techniques offer a useful tool to quantify the effect of Fuller's earth. Experimental investigations performed in laboratory conditions have shown that the quality of properly reclaimed aged oil can compete with that of new oils. Thus, in addition to extending the life cycle of this non-renewable resource, on-line reclamation of liquid might also prevent the premature ageing of paper insulation. Studying the stability of reclaimed service aged oil samples emphasized the important role played by Fuller's earth absorption capability. 展开更多
关键词 Insulating oil RECLAMATION Fuller's earth TURBIDITY SPECTROPHOTOMETER decay product gassing tendency.
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什么情况下需要散瞳验光
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作者 陶海 《大众医学》 2007年第8期72-72,共1页
我女儿10岁,戴300度的近视眼镜,现在想看看她的视力有没有变化,去验光还需要散瞳吗?
关键词 散瞳验光 近视眼镜 假性近视者 儿童 验光条件
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Anti-aging properties of Ribes fasciculatum in Caenorhabditis elegans 被引量:6
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作者 Hoon Jeon Dong Seok Cha 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2016年第5期335-342,共8页
The present study investigated the effects and underlying mechanism of ethylacetate fraction of Ribes fasciculatum (ERF) on the lifespan and stress tolerance using a Caenorhabditis elegans model. The longevity activ... The present study investigated the effects and underlying mechanism of ethylacetate fraction of Ribes fasciculatum (ERF) on the lifespan and stress tolerance using a Caenorhabditis elegans model. The longevity activity of ERF was determined by lifespan assay under normal culture condition. The survival rate of nematodes under various stress conditions was assessed to validate the effects of ERF on the stress tolerance. To determine the antioxidant potential of ERF, the superoxide dismutase (SOD) activities and intracellular reactive oxygen species (ROS) levels were investigated. The ERF-mediated change in SOD-3 expression was examined using GFP-expressing transgenic strain. The effects of ERF on the aging-related factors were investigated by reproduction assay and pharyngeal pumping assay. The intestinal lipofuscin levels of aged nematodes were also measured. The mechanistic studies were performed using selected mutant strains. Our results indicated that ERF showed potent lifespan extension effects on the wild-type nematode under both normal and various stress conditions. The ERF treatment also enhanced the activity and expression of superoxide dismutase (SOD) and attenuated the intracellular ROS levels. Moreover, ERF-fed nematodes showed decreased lipofuscin accumulation, indicating ERF might affect age-associated changes in C. elegans. The results of mechanistic studies indicated that there was no significant lifespan extension in ERF-treated daf-2, age-l, sir-2.1, and daf-16 null mutants, suggesting that they were involved in ERF-mediated lifespan regulation. In conclusion, R. fasciculatum confers increased longevity and stress resistance in C. elegans via SIR-2.1-mediated DAF-16 activation, dependent on the insulin/1GF signaling pathway. 展开更多
关键词 Ribesfasciculatum LIFESPAN AGING Stress tolerance Caenorhabditis elegans
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Experimental Study on Dual-Wavelength Distributed Feedback Fiber Laser
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作者 Haifeng QI Zhiqiang SONG Jian GUO Chang WANG Jun CHANG Gangding PENG 《Photonic Sensors》 SCIE EI CAS 2014年第3期225-229,共5页
Four distributed feedback fiber lasers with dual-wavelength operations were studied experimentally in detail. The laser characteristics of these distributed feedback fiber lasers (DFB-FLs) were investigated. The ope... Four distributed feedback fiber lasers with dual-wavelength operations were studied experimentally in detail. The laser characteristics of these distributed feedback fiber lasers (DFB-FLs) were investigated. The operation conditions for the dual-wavelength output are analyzed and presented. Through this study, the guidance of the design and fabrication of some dual-wavelength distributed feedback fiber lasers are provided. 展开更多
关键词 Distributed feedback fiber laser dual wavelength phase shift optical fiber sensing
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Study of TiO_2 thin films on Si substrate by the photoacoustic elastic bending method
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作者 TODOROVI Dragan M RABASOVI Mihailo D +2 位作者 MARKUSHEV Dragan D FRANKO Mladen TANGAR Urka Lavreni 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第7期1285-1293,共9页
The quantitative photoacoustic investigation of different TiO2 thin films on Si substrates is presented using the elastic bending method. Photoacoustic signal amplitude and phase spectra versus modulation frequency we... The quantitative photoacoustic investigation of different TiO2 thin films on Si substrates is presented using the elastic bending method. Photoacoustic signal amplitude and phase spectra versus modulation frequency were measured and analyzed using different sample thicknesses. Within the proposed method particular attention is given to the analysis of optical, thermal, elastic and structural sample parameters. Considerable focus is devoted to the fitting procedure of experimental results using the two-layer sample theoretical model. Characteristics of previously developed photoacoustic apparatus are discussed, attempting to search the ideal experimental conditions which can provide a good signal-to-noise ratio and sensitivity. 展开更多
关键词 PHOTOACOUSTIC TIO2 thin films
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