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下水启闭器的制作与应用
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作者 代金凤 《数码设计》 2020年第23期134-134,共1页
现在住宅小区、企业办公楼和厂房车间一楼所使用的通用下水道装置有直通式、水封装置和弹簧式地漏,其反水、反味的功能不健全,达不到人们对高品质生活质量和办公环境的要求,所以利用专业优势,结合一体化教学特点,萌发了利用流体力学的原... 现在住宅小区、企业办公楼和厂房车间一楼所使用的通用下水道装置有直通式、水封装置和弹簧式地漏,其反水、反味的功能不健全,达不到人们对高品质生活质量和办公环境的要求,所以利用专业优势,结合一体化教学特点,萌发了利用流体力学的原理,在与下水道连接部位安装自动启闭器装置,来解决下水堵塞等诸多困扰。 展开更多
关键词 堵塞 反味 制作 应用
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The Content of Selenium and Other Ten Chemical Elements in Boletus Edulis from Bulgaria and Inhibition of Lipid Peroxidation
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作者 G. Bekyarov M. Kakalova +6 位作者 A. Iliev Tsv. Bekyarova G.V. Donchenko O.M. Palyvoda O.V. Vydiuk A.S.Dubovetskyi O.I. Kuzmenko 《Journal of Environmental Science and Engineering》 2011年第6期708-715,共8页
The goal of this study was to determine the content of such biological active metals as Se, Hg, AI, Cu, Zn, As, Cd, Pb, Mg, Ca and Fe in Boletus Edulis mushrooms and to study the effect of mushrooms as inhibitors of b... The goal of this study was to determine the content of such biological active metals as Se, Hg, AI, Cu, Zn, As, Cd, Pb, Mg, Ca and Fe in Boletus Edulis mushrooms and to study the effect of mushrooms as inhibitors of blood serum copper-initiated lipid peroxidation. The metals content was determined by ICP-OES technique and blood lipids peroxidation in vitro was assessed by thiobarbituric acid-reactive substances measurement. The dependency between quality and content of the determined biological active metals has been traced. Samples were analyzed of wild growing mushrooms Boletus Edulis from two mountain regions in Bulgaria. On the average the content of Se in Boletus Edulis was found to be 25 mg/kg dried mushroom, this content being higher in tubules than in fleshy part. We found that Boletus Edulis mushrooms inhibited lipid peroxidation in the concentration dependent manner. The effective concentration of Boletus Edulis is in 5 times lower compared to the concentration of Cantharellus Cibarius resulting in similar lipid peroxidation inhibition. This effect can be explained by 56 times higher content of Se and by 1.5 and 3 times lower content of such initiators of lipid peroxidation as Cu and Fe in Boletus Edulis compared to Cantharellus Cibarius. A system with a source of infrared radiation heating, developed by authors, was used for the mushroom mineralization. We conclude that Boletus Edulis is an effective inhibitor of blood lipid peroxidation and in 5 times stronger rather than Cantharellus Cibarius. 展开更多
关键词 Boletus edulis ICP-OES heavy metals SELENIUM lipid peroxidation ANTIOXIDANTS
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Quark-Antiquark and Diquark Condensates in Vacuum in a 3D Two-Flavor Gross-Neveu Model
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作者 ZHOU Bang-Rong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第4期695-698,共4页
The effective potential analysis indicates that, in a 3D two-flavor Gross-Neveu model in vacuum, depending on whether Gs/Hp is less or bigger than the critical value 2/3, where G s and H p are respectively the couplin... The effective potential analysis indicates that, in a 3D two-flavor Gross-Neveu model in vacuum, depending on whether Gs/Hp is less or bigger than the critical value 2/3, where G s and H p are respectively the coupling constants of scalar quark-antiquark channel and pseudoscalar diquark channel, the system will have the ground state with pure diquark condensates or with pure quark-antiquark condensates, but never with coexistence of the two forms of condensates. The similarities and differences in the interplay between the quark-antiquark and the diquark condensates in vacuum in the 2D, 3D and 4D two-flavor four-fermion interaction models are summarized. 展开更多
关键词 3D Gross-Neveu model quark-antiquark and diquark condensates effective potential
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Quark-Antiquark and Diquark Condensates in Vacuum in a 2D Two-Flavor Gross-Neveu Model
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作者 ZHOU Bang-Rong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期520-524,共5页
The analysis based on the renormalized effective potential indicates that, similar to in the 4D two-flavor Nambu-Jona-Lasinio (NJL) model, in a 2D two-flavor Gross-Neveu model, the interplay between the quark-antiqu... The analysis based on the renormalized effective potential indicates that, similar to in the 4D two-flavor Nambu-Jona-Lasinio (NJL) model, in a 2D two-flavor Gross-Neveu model, the interplay between the quark-antiquark and the diquark ,condensates in vacuum also depends on Gs/Hs, the ratio of the coupling constants in scalar quarkantiquark and scalar diquark channel. Only the pure quark-antiquark condensates exist if Gs/Hs 〉 2/3, which is just the ratio of the color numbers of the quarks participating in the diquark and quark-antiquark condensates. The two condensates will coexist if 0 〈 Gs/Hs 〈 2/3. However, different from the 4D NJL model, the pure diquark condensates arise only at Gs/Hs = 0 and are not in a possibly finite region of Gs/Hs below 2/3. 展开更多
关键词 2D Gross-Neveu model quark-antiquark and diquark condensates effective potential RENORMALIZATION mean-field approximation
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Why not to avoid the smell of danger? Unexpected behavior of the Cypriot mouse surviving on the island invaded by black rats 被引量:2
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作者 Daniel FRYNT Margareta BALADOVA +2 位作者 Barbora ELIASOVA Silvie LISKOVA Eva LANDOVA 《Current Zoology》 SCIE CAS CSCD 2015年第4期781-791,共11页
Mus cypriaeus is a recently discovered endemic species that evolved about half a million years ago on the Cyprus Is- land in an absence of most mammalian predators and competitors. As on other Mediterranean islands, t... Mus cypriaeus is a recently discovered endemic species that evolved about half a million years ago on the Cyprus Is- land in an absence of most mammalian predators and competitors. As on other Mediterranean islands, the faunal composition was dramatically changed by the invasion of commensal and domestic species following Holocene colonization by humans. We exa- mined the behavioral responses of the Cypriot mouse to the odors of these new competitors (black and Norway rat, house mouse and spiny-mouse) and predator (domestic cat) as well as controls (Herb-field mouse, guinea pig). We compared them with those of mainland population of house mouse from Syria with different coexistence history. Surprisingly, the Cypriot mouse failed to avoid the odor of its current main competitor, the black rat. Moreover, the response patterns of both the Cypriot and Syrian house mice to the examined odor sources appeared fairly comparable. There was a clear tendency to prefer odors of other murids over unscented sawdust as well as to avoid the odor of a domestic cat. In conclusion, neither the long-term isolation from predators nor the recent strong competition with black rats affected mice eompetitory and antipredatory responses fundamentally [Current Zoology 61 (4): 781-791, 2015]. 展开更多
关键词 COMPETITION Cyprus Mus cypriacus Odor preference Rattus rattus
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Estimating mean trabecular bone spacing based on the combination of Hilbert transform and fundamental frequency estimation
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作者 李颖 徐峰 +3 位作者 刘成成 许凯亮 他得安 王威琪 《Science Foundation in China》 CAS 2017年第3期57-71,共15页
Ultrasonic backscatter signals from cancellous bone are sensitive to the microstructure of trabecular bone,and thus enable the feasibility to extract microstructural information of trabecular bone.The mean trabecular ... Ultrasonic backscatter signals from cancellous bone are sensitive to the microstructure of trabecular bone,and thus enable the feasibility to extract microstructural information of trabecular bone.The mean trabecular bone spacing(MTBS)is an important parameter for characterizing bone microstructure.This paper proposes an MTBS estimation method based on the combination of Hilbert transform and fundamental frequency estimation(CHF). The CHF was verified with ultrasonic backscatter signals from simulations and in vitro measurements at a central frequency of 5MHz.The CHF method was compared with the simplified inverse filter tracking(SIFT)method,Simons' Quadratic Transformation(QT)method,Singular Spectrum Analysis(SSA)method,and Spectral Autocorrelation(SAC)method.Monte-Carlo simulations were performed by varying the MTBS,signal-to-noise ratio(SNR),standard deviation of regular spacing(SDRS),amplitude ratio of diffuse scattering to regular scattering(Ad)and frequency dependent attenuation(nBUA).The simulation results showed that the CHF method had a better performance in MTBS estimation under almost all the examination conditions except for SNR.The estimation percentage correct(EPC)was greater than 90% when the MTBS was in the range of 0.4to 1.4mm.In the in vitro measurements,the estimated EPC by the CHF method was91.25±7.81%(mean±standard deviation).A significant correlation was observed for the CHF-estimated MTBS and micro-computed tomography(μ-CT)-measured values(R^2=0.75,p<0.01).These results demonstrate that the CHF method is anti-interference for MTBS estimation and can be used to estimate trabecular bone spacing. 展开更多
关键词 Ultrasonic backscatter Mean trabecular bone spacing estimation Hilbert transform and fundamental frequency estimation Cancellous bone microstructure
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Effects of historically familiar and novel predator odors on the physiology of an introduced prey
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作者 Valentina S. A. MELLA Christine E. COOPER Stephen J. J. F. DAVIES 《Current Zoology》 SCIE CAS CSCD 2016年第1期53-59,共7页
Predator odors can elicit fear responses in prey and predator odor recognition is generally associated with physiological responses. Prey species are often more likely to respond to the odor of familiar ra- ther than ... Predator odors can elicit fear responses in prey and predator odor recognition is generally associated with physiological responses. Prey species are often more likely to respond to the odor of familiar ra- ther than alien predators. However, predator na'ivety in an introduced prey species has rarely been investigated. We examined the physiological response, as shown by changes in ventilatory vari- ables, of an introduced terrestrial herbivore, the European rabbit Oryctolagus cuniculus, in Australia, to the odor of potential predators and to control odors (distilled water and horse), to explore if res- ponses were limited to historical (cat and fox) predators, or extended to historically novel predators (snake and quoll). All odors except distilled water elicited a response, with rabbits showing long- term higher respiratory frequencies and lower tidal volumes after introduction of the odors, indi- cating an increase in alertness. However, the intensity of the rabbits' reaction could not be directly linked to any pattern of response with respect to the history of predator-prey relationships. Rabbits exhibited significantly stronger reactions in response to both cat and quoll odors than they did to dis- tilled water, but responses to horse, fox, and snake odor were similar to that of water. Our results show that the introduced rabbit can respond to both historical and novel predators in Australia, and suggest that shared evolutionary history is not necessarily a prerequisite to predator odor recognition. 展开更多
关键词 PHYSIOLOGY ventilation predator odor RABBIT introduced prey predator naivety.
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Do females influence paternal responsiveness in male prairie voles Microtus ochrogaster by increasing the salience of infant odors?
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作者 Damaris-Lois LANG YAMOAH Wilhemina LARYEA +1 位作者 Fiker FASSIL Maryam BAMSHAD 《Current Zoology》 SCIE CAS CSCD 2013年第3期317-325,共9页
Male prairie voles become more responsive to infants following cohabitation with a female. Exposure to female sen- sory cues prior to offspring birth may influence male paternal tendencies by modifying his response to... Male prairie voles become more responsive to infants following cohabitation with a female. Exposure to female sen- sory cues prior to offspring birth may influence male paternal tendencies by modifying his response to infant odors in particular or to odors in general. To test these hypotheses, males were housed with an unfamiliar female or a same-sex sibling for 13 days then examined for their response towards either live infants or infant-like inanimate objects covered with one of three odors: wa- ter, infant, sub-adult. We recorded the number of males that retrieved and manipulated the infants or odor-covered objects and measured the frequency and duration of time males spent attending to them or engaged in other non-social activities. Fe- male-Cohabited males approached the container holding infant-odor covered objects faster than Male-Cohabited males, but showed no differences in time spent manipulating those objects. Males in both groups spent more time manipulating live infants than odor-covered objects. However, Female-Cohabited subjects were more likely to manipulate odor-covered objects as well as live infants than Male-Cohabited subjects. Additionally, the frequency of self-grooming in Female-Cohabited males was higher for water-covered objects compared to Male-Cohabited males. In presence of water and live infants, Female-Cohabited males groomed themselves with greater frequency than in presence of infant odor or sub-adult odor. The data suggest that female cues increase the male's sensitivity to infant odors and enhance the salience of non-social odors. 展开更多
关键词 Biparental Social cognition Social attention Social odors Odor perception Sensory perception
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