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1.
This study predicts that quasi-periodic oscillations could exist in a detailed model of glycolysis that is analyzed in an autonomous system. In addition to period-doubling, quasi-periodic and period-adding bifurcation, a new stationary branch, which lies in between the thermodynamic and flow branches, is also uncovered in the glycolytic reaction system. Results presented in this study illustrate that the Michaelis constant (K4GAP) of glyceraldehyde 3-phosphate dehydrogenase for glyceraldehyde 3-phosphate has great influences on glycolytic oscillations, in which increasing K4GAP widens the range of flow rate over which quasi-periodic oscillations exist.  相似文献   

2.
The authors discuss the concept of meta-information which is the desription of information system or its subsystems,and proposes algorithms for meta-information generation.Meta-information can be generated in parallel mode and network computation can be used to accelerate meta-information generation.Most existing rough set methods assume information system to be centralized and cannot be applied directly in distributed information system.Data integration ,which is costly,is necessary for such existing methods.However,meta-information integration will eliminate the need of data integration in many cases,since many rough set operations can be done straightforward based on meta-information,and many existing methods can be modified based on meta-information.  相似文献   

3.
Multiple products of B-splines used in CAD system   总被引:1,自引:1,他引:1  
The function upgrade of computer aided design (CAD) system requested that the multiple product of B-spline functions should be represented as a linear combination of some suitable (usually higher-degree) B-splines. In this paper, we apply the theory of spline space and discrete B-splines to deduce the representation of the coefficients of all terms of the linear combination, which can be directly applied to software coding in system development.  相似文献   

4.
Metapopulations are ecological models describing the interactions and the behavior of populations living in fragmented habitats. In this paper, metapopulations are modelled by means of dynamical probabilistic P systems, where additional structural features have been defined (e.g., a weighted graph associated with the membrane structure and the reduction of maximal parallelism). In particular, we investigate the influence of stochastic and periodic resource feeding processes, owing to seasonal variance, on emergent metapopulation dynamics.  相似文献   

5.
Sources of matrix-bound phosphine in advanced wastewater treatment system   总被引:2,自引:0,他引:2  
Phosphine (PH3), a highly toxic and reductive gas, has been explored in biogases and it proves also to be ubiquitous even in remote atmospheric air at a concentration in the order of (pg-ng) /m^3 [3]. For more than one hundred years, sources and mechanisms of biological phosphine formation in natural and engineered environments have been investigated and discussed. Anaerobic environments were reported to be the main source of phosphine emission.  相似文献   

6.
Shared-nothing spatial database cluster system provides high availability since a replicated node can continue service even if any node in cluster system was crashed. However if the failed node wouldn‘t be recovered quickly, whole system performance will decrease since the other nodes must process the queries which the failed node may be processed. Therefore the recovery of cluster system is very important to provide the stable service. In most previous proposed techniques, external logs should be recorded in all nodes even if the failed node does not exist. So update transactions are processed slowly. Also recovery time of the failed node increases since a single storage for all database is used to record external logs in each node. Therefore we propose a parallel recovery method for recovering the failed node quickly.  相似文献   

7.
Mechanism and estimation of negative entropy flow in terrestrial system   总被引:2,自引:0,他引:2  
The origin, existence and evolution of life on the earth depend on the negative entropy flow in the terrestrial system (TS). In this paper, we investigate the mechanisms of different negative entropy flows caused by the vertical heat transfer of water phase transition and the gravitational field effect, and the vertical atmospheric heat transfer and the gravitational field effect, under the influences of the sun's radiation, the photosynthesis of the plants, and the earth's rotation. The magnitude orders and the mechanisms of the abovementioned negative entropy flow are also discussed.  相似文献   

8.
Insertional mutagenesis based on maize Activator/Dissociator (Ac/Ds) transposons is becoming a ma- jor approach used to produce a saturated mutant collection in rice. In this research, Ds-T-DNA trans- formed homozygotes were crossed with Ac-T-DNA transformed homozygotes in order to establish an Ac/Ds transposon system in rice. The successive investigation of Ds transposition from F1 to F5 gen- erations indicated that the frequencies of germinal transposition increased over successive genera- tions and reached 54.2% in F3 generation. The Ds transposition pattern revealed that a Ds transposition induced an approximately 170-bp deletion of T-DNA sequence and another Ds transposition carried a 272-bp T-DNA sequence. Using thermal asymmetric interlaced PCR (TAIL-PCR), some flanking se- quences of the Ds element were amplified. Analyses of 17 Ds-flanking sequences showed that five Ds were inserted into gene regions. The Ds could transpose not only to the linked sites but also to the unlinked sites. The frequency of inter-chromosomal transposition of Ds was 33.3%.  相似文献   

9.
The phase relationships of the complex multi-component systems in the liquid-phase oxidization and separation process related with the chromate cleaner production are investigated theoretically and experimentally.The phase diagram of main system Fe- Cr_2O_4-KOH-O_2 of oxidization process and the relationship of its standard Gibbs free energy change with temperature are calculated.A se- ries of phase diagrams of the separation process at different temperatures,such as K(Na)OH-K(Na)_2CrO_4-H_2O,KOH-KAlO_2-H_2O, K(Na)OH-K(Na)_2CO_3-H_2O,K(Na)OH-K(Na)HCO_3-H_2O and K(Na)HCO_3-K(Na)_2CrO_4-H_2O have also been calculated.Some ex- periments are carried out to verify the calculated results.Our results showed that the sub-molten salt media are suitable for the oxidization and separation processes;FeCr_2O_4 can be oxidized across a wide range of temperature;K(Na)_2CrO_4 can be separated from K(Na)AlO_2 system at appropriate temperature and proper concentration;the crystallization of carbonate is easier than that of K(Na)_2CrO_4.  相似文献   

10.
AnimprovementinselfconsistentclustermethodfordeterminingthecriticalpointinIsingspinsystem¥ZhengRuilun;PingRonggang(Department...  相似文献   

11.
The transport of non-aqueous phase liquids (NAPLs) in unsaturated soils and groundwater is an important research topic in geo-environmental engineering. In this paper, the mechanism of light NAPLs (LNAPLs) transport in subsurface system is briefly introduced, and the mass transport equations, fluid flow equations, and the constitutive model of relative permeability - saturation - capillary pressure are discussed. Then the numerical method is introduced to simulate the multiphase flow problems in porous media, and the tempo-spatial distribution of LNAPLs is obtained. Moreover, different boundary conditions are employed in numerical simulation to investigate its effect on transport behavior. To verify the numerical data, centrifugal tests are conducted to model the LNAPLs migration in unsaturated soils and groundwater. The calculation results are agreeable with the experimental findings of centrifugal modeling, which indicates that LNAPLs from leaking point move downwards due to gravity force, and form a high concentration zone above the capillary fringe, and then spread out laterally along the groundwater table. Some LNAPL enters groundwater system to further migrate. The combination of numerical simulation and centrifuge modeling can be a useful means to study the transport behavior of LNAPLs in subsurface system.  相似文献   

12.
F-MSAP: A practical system to detect methylation in chicken genome   总被引:5,自引:0,他引:5  
By replacing radiation with fluorescent system in the technique of methylation sensitive amplified polymorphism (MSAP) and optimizing reaction conditions, a modified technique to detect DNA methylation called F-MSAP (fluorescent labeled methylation sensitive amplified polymorphism) was developed. In the present study, cytosine methylation patterns of genomic DNA were investigated in two inbred chickens and their F1 hybrids. Three types of methylation patterns were observed in each individual, namely fully methylated, hemi-methylated or not methylated types. The average incidence of methylation was approximately 40%. The percentage that the F1 hybrid individual inherits the methylation for any given sites from either/both parent amounted to 95%, while the percentage of altered methylation patterns in F1 individual was only 5%, including 14 increased and 12 decreased methylation types, demonstrating that F-MSAP was highly efficient for large-scale detection of cytosine methylation in chicken genome. Our technique can be further extended to other animals or plants with complex genome and rich in methylation polymorphism.  相似文献   

13.
In decision support system for spatial site selection, the fuzzy synthetic evaluation is a useful way. However, the method can’t pay attention to the randomness in factors. To remedy the problem, this paper proposes a clouded-base fuzzy approach which combines advantages of cloud transform and fuzzy synthetic evaluation. The cloud transform considers the randomness in the factors and product the higher concept layer for data mining. At the same time, the check mechanism controls the quality of partitions in factors. Then the fuzzy approach was used to get final evaluation value with randomness and fuzziness. It make the final result is optimization. Finally, performance evaluations show that this approach spent less runtime and got more accuracy than the fuzzy synthetic. The experiments prove that the proposed method is faster and more accuracy than the original method.  相似文献   

14.
Quasirational dynamic system   总被引:1,自引:0,他引:1  
Using the iterations of quasirational mappings, the theorems on dynamic system are generalized to the quasirational dynamic system. Some different results are also obtained.  相似文献   

15.
16.
In China, the marine Jurassic is mainly distributed in the Qinghai-Tibetan Plateau, southwestern China and environs including southwestern Xinjiang and western Yunnan. Along the western palaeo-Pacific coast, marine Jurassic deposits, which usually intercalate with nonmarine strata, exist sporadically in eastern Heilongjiang, western Fujian, Hongkong, central Guangdong, western Jiangxi, eastern and southwestern Hunan Province, and probably also in western Taiwan. Nonmarine Jurassic strata are widely distributed in the whole of China except for southern Tibet area. They are commonly intercalated with volcanic rocks and contain volcanic materials in eastern China, and in southern Tibet. Marine strata yield various abundant fossils including ammonites, which were widespread in the Tethyan Realm even all over the world. Consequently, China is a critical region to attempt marine and non-marine Jurassic correlation. Through various investigations, both marine and non-marine Jurassic biozonations or assemblages have been established and by this the marine and non-marine Jurassic stratigraphic system and their correlation in China have been clarified.  相似文献   

17.
During the process of lysozyme protein crystallization with batch method,the macroscopic flow field of solid/liquid system was observed by particle image velocimetry(PIV). Furthermore,a normal growth rate of(110) face and local flow field around a single protein crystal were obtained by a long work dis-tance microscope. The experimental results showed that the average velocity,the maximal velocity of macroscopic solid/liquid system and the velocity of local flow field around single protein crystal were fluctuant. The effective boundary layer thickness δeff,the concentration at the interface Ci and the characteristic velocity V were calculated using a convection-diffusion model. The results showed that the growth of lysozyme crystal in this experiment was dominated by interfacial kinetics rather than bulk transport,and the function of buoyancy-driven flow in bulk transport was small,however,the effect of bulk transport in crystal growth had a tendency to increase with the increase of lysozyme concentra-tion. The calculated results also showed that the order of magnitude of shear force was about 10-21 N,which was much less than the bond force between the lysozyme molecules. Therefore the shear force induced by buoyancy-driven flows cannot remove the protein molecules from the interface of crystal.  相似文献   

18.
《科学通报(英文版)》1998,43(16):1353-1353
Through inserting a solid oxygen-specific electrolyte (YSZ) inside and exerting an electrical power of direct current outside between the sample and oxygen reservoir (an solid oxygen buffer), oxygen was driven by the power from the cathodic electrode area into the positive electrode area at high temperature and high pressure. In this way, the oxygen fugacity in the sample was in situ controlled independently of temperature and pressure. By using Cu-O system as an example, this technique was proved to be successful.  相似文献   

19.
In China, the marine Jurassic is mainly distributed in the Qinghai-Tibetan Plateau, southwestern China and environs including southwestern Xinjiang and western Yunnan. Along the western palaeo-Pacific coast, marine Jurassic deposits, which usually intercalate with nonmarine strata, exist sporadically in eastern Heilongjiang, western Fujian, Hongkong, central Guangdong, western Jiangxi, eastern and southwestern Hunan Province, and probably also in western Taiwan. Nonmarine Jurassic strata are widely distributed in the whole of China except for southern Tibet area. They are commonly intercalated with volcanic rocks and contain volcanic materials in eastern China, and in southern Tibet. Marine strata yield various abundant fossils including ammonites, which were widespread in the Tethyan Realm even all over the world. Consequently, China is a critical region to attempt marine and non-marine Jurassic correlation. Through various investigations, both marine and non-marine Jurassic biozonations or assemblages have been established and by this the marine and non-marine Jurassic stratigraphic system and their correlation in China have been clarified.  相似文献   

20.
Photoconducting organic materials including conju-gated polymers[1―3], organic molecules[4,5], stacked disco- stic liquid crystals[6,7] and self-assembling organic semi-conductors[8,9] have attracted intense interests due to their extraordinary performances. Their charge carrier photo-generation mechanism has been one of the most important subjects of large amounts of publications in view of possi-ble applications in electronic devices such as photovoltaic cells[10―19]. The charge carrier ph…  相似文献   

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