33 resultados para REGULARITY

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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针对高体积份数、随机分布、等轴状颗粒增强复合材料 ,研究了材料的应变分布规律 ,给出了基体和增强体应变平均值与材料微观结构参数之间的定量关系。结果表明 ,除应变平均值外 ,应变涨落是影响刚度张量的另一个重要因素 ,研究了应变涨落与材料微观结构参数之间的关系 ,并推导出了复合材料的刚度张量。与实验结果和以往的理论比较 ,预测结果与实验结果吻合良好

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Based on studies on the strain distribution in short-fiber/whisker reinforced metal matrix composites, a deformation characteristic parameter, lambda is defined as a ratio of root-mean-square strain of the reinforcers identically oriented to the macro-linear strain along the same direction. Quantitative relation between lambda and microstructure parameters of composites is obtained. By using lambda, the stiffness moduli of composites with arbitrary reinforcer orientation density function and under arbitrary loading condition are derived. The upper-bound and lower-bound of the present prediction are the same as those from the equal-strain theory and equal-stress theory, respectively. The present theory provides a physical explanation and theoretical base for the present commonly-used empirical formulae. Compared with the microscopic mechanical theories, the present theory is competent for stiffness modulus prediction of practical engineering composites in accuracy and simplicity.

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The voltage-current properties during plasma electrolytic discharge were determined by measuring the current density and cell voltage as functions of processing time and then by mathematical transformation. Correlation between discharge I-V property and the coatings microstructure on aluminum alloy during plasma electrolfic oxidation was determined by comparing the voltage-current properties at different process stages with SEM results of the corresponding coatings. The results show that the uniform passive film corresponds to a I-V property with one critical voltage, and a compound of porous layer and shred ceramic particles corresponds to a I-Vproperty with two critical voltages. The growth regularity of PEO cermet coatings was also studied.

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In this paper, we study some degenerate parabolic equation with Cauchy-Dirichlet boundary conditions. This problem is considered in little Holder spaces. The optimal regularity of the solution v is obtained and is specified in terms of those of the second member when some conditions upon the Holder exponent with respect to the degeneracy are satisfied. The proofs mainly use the sum theory of linear operators with or without density of domains and the results of smoothness obtained in the study of some abstract linear differential equations of elliptic type.

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The stress release model, a stochastic version of the elastic rebound theory, is applied to the large events from four synthetic earthquake catalogs generated by models with various levels of disorder in distribution of fault zone strength (Ben-Zion, 1996) They include models with uniform properties (U), a Parkfield-type asperity (A), fractal brittle properties (F), and multi-size-scale heterogeneities (M). The results show that the degree of regularity or predictability in the assumed fault properties, based on both the Akaike information criterion and simulations, follows the order U, F, A, and M, which is in good agreement with that obtained by pattern recognition techniques applied to the full set of synthetic data. Data simulated from the best fitting stress release models reproduce, both visually and in distributional terms, the main features of the original catalogs. The differences in character and the quality of prediction between the four cases are shown to be dependent on two main aspects: the parameter controlling the sensitivity to departures from the mean stress level and the frequency-magnitude distribution, which differs substantially between the four cases. In particular, it is shown that the predictability of the data is strongly affected by the form of frequency-magnitude distribution, being greatly reduced if a pure Gutenburg-Richter form is assumed to hold out to high magnitudes.

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The stress release model, a stochastic version of the elastic-rebound theory, is applied to the historical earthquake data from three strong earthquake-prone regions of China, including North China, Southwest China, and the Taiwan seismic regions. The results show that the seismicity along a plate boundary (Taiwan) is more active than in intraplate regions (North and Southwest China). The degree of predictability or regularity of seismic events in these seismic regions, based on both the Akaike information criterion (AIC) and fitted sensitivity parameters, follows the order Taiwan, Southwest China, and North China, which is further identified by numerical simulations. (c) 2004 Elsevier Ltd. All rights reserved.

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热浸镀铝钢经等离子体电解氧化(Plasma Electrolytic Oxidation,PEO)处理后,表面铝镀层转化为陶瓷层.实验对阳极电压变化、陶瓷层生长规律、涂层截面形貌和成分等进行了研究.结果表明:在PEO初期,热浸铝试件的阳极电压变化趋势与纯铝试件相同,在PEO后期电压有下降趋势.铝镀层消耗和陶瓷层厚度增长近似为线性变化.当铝镀层完全陶瓷化后,FeAl层参与PEO反应,但陶瓷层生长速率变慢,在界面处出现大量裂纹;陶瓷层主要成分为Al、Si、O元素,相结构主要为γ-Al_2O_3与莫来石相,在PEO后期出现α-Al_2O_3相.复合陶瓷层硬度呈区域性分布,陶瓷层最高硬度可达HV1800.

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Several discharge areas by laser-guided discharge (LGD) were compared with those by common arc discharge. The randomicity of discharge areas by common arc discharge was controlled by laser guiding on two scales: large scale (the spacing of the discharge areas) and small scale (the inside of the discharge area). The position of the discharge area overlapped completely with a laser focus; therefore, the distribution and surface shape of the discharge areas were controlled. The stochastic movement of anode spot in the discharge area was controlled by laser guiding. As such, the repetitive melting and solidifying of microstructures in the discharge area was constrained. The tempered microstruc- tures in the discharge area were voided, the utilization efficiency of input energy was improved, and the strengthened depth of the discharge areas was increased. The regularity of cross-sectional shape of the discharge area was also improved. The hardness of microstructures in both discharge areas is greater than that of the base material. The highest level of hardness of microstructures in both discharge areas measures above 1000 HV. In summary, the hardness ofmicrostructures in the discharge area by LGD is larger and more discrete than that by common arc discharge.

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对双源线性共蒸法制备的非均匀薄膜折射率分布与光学特性的关系作了探讨,并与均匀介质膜的光学特性作了对比;从折射率正变和负变两个方面.讨论了混合介质膜折射率不同变化规律对光学性能带来的影响;讨论了厚度误差和折射率极值误差对非均匀膜光学性能的影响。结果发现:折射率变化规律误差主要对非均匀膜的应用波段范围产生影响,而膜层厚度误差和折射率极值误差超过一定值时,将对薄膜光学特性产生重要影响。

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Drug addiction is increasingly viewed as the expression of abnormal associative learning following repeated exposures to the drugs of abuse Previous I studies have demonstrated that the patterns of repetition such as frequency and spacing are important to many kinds of learning and memory retention We hypothesized that drug repetition pattern might affect the reward-related learning although the total doses of the drug were the same. In the present study, we tested morphine-induced place preference following either regular or irregular pattern of morphine pairing in rats Regular morphine group received morphine administration daily at a regular time with the same dose Irregular morphine groups received morphine administration either at the same time but irregular doses, irregular time but same dose, or irregular time and irregular doses. We found that rats, who received irregular morphine pairing, exhibited similar acquisition of peace preference but different preference retentions compared with regular morphine-treated rats after the same total dose of morphine Rats, who received morphine administration at the same time but irregular doses and at irregular time and irregular doses, showed rapid disruption of place preference than the regular morphine group. Rats, who received morphine at irregular time but the same dose, showed similar retention of place preference to regular morphine group Our results suggest that the pattern of drug pairing plays an important role in the retention of reward-related memory This study may provide new evidence to broaden our understanding of the development and maintenance of drug craving (C) 2009 Elsevier B V. All rights reserved

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A convenient fabrication technology for large-area, highly-ordered nanoelectrode arrays on silicon substrate has been described here, using porous anodic alumina (PAA) as a template. The ultrathin PAA membranes were anodic oxidized utilizing a two-step anodization method, from Al film evaporated on substrate. The purposes for the use of two-step anodization were, first, improving the regularity of the porous structures, and second reducing the thickness of the membranes to 100 similar to 200 nm we desired. Then the nanoelectrode arrays were obtained by electroless depositing Ni-W alloy into the through pores of PAA membranes, making the alloy isolated by the insulating pore walls and contacting with the silicon substrates at the bottoms of pores. The Ni-W alloy was also electroless deposited at the back surface of silicon to form back electrode. Then ohmic contact properties between silicon and Ni-W alloy were investigated after rapid thermal annealing. Scanning electron microscopy (SEM) observations showed the structure characteristics, and the influence factors of fabrication effect were discussed. The current voltage (I-V) curves revealed the contact properties. After annealing in N-2 at 700 degrees C, good linear property was shown with contact resistance of 33 Omega, which confirmed ohmic contacts between silicon and electrodes. These results presented significant application potential of this technology in nanosize current-injection devices in optoelectronics, microelectronics and bio-medical fields.

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土壤CO2释放通量总量与潜力作为陆地土壤碳循环过程研究的重要组分,一直是国际统碳循环研究的前沿领域。鉴于温带森林对全球气候变化的敏感性,以阔叶红松林为代表的土壤CO2 放通量过程与机制的研究,能够为正确评估我国温带森林土壤碳库动态和潜力提供科学依据。本文利用静态箱/气相色谱技术,连续测定了长白山阔叶红松林及其附近的次生林土壤CO2释放通量并进行比较研究,结果表明:(1)长白山阔叶红松林土壤CO2释放通量具有明显的季节动态,与温度的变化趋势大致相同,在生长季节中表现出8月份>7月份>9月份>5月份>4月份。(2)土壤温度是控制CO2释放的关键驱动因子;土壤含水量变化对CO2 释放亦有一定的影响。(3)不同土壤类型的土壤COZ释放通量强度不同,其中阔叶红松林年C排放量为7253.72 kg/hm2,白桦林排放量为6581.28 kg/hm2,山杨白桦混交林和山杨林排放量分别是6301.64 kg/hm2和4941.77 kg/hm2。(4)凋落物对林地CO2释放有显著的影响,贡献率约占-12%-38%;根系的贡献约为7.26%-57.6%。

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横断山地区是一个十分自然的植物区系地区,在中国植物区系分区中是作为泛北极植物区中国-喜马拉雅亚区中的一个地区,其种子植物区系具有丰富的科、属、种,地理成分复杂,特有现象和替代现象明显。该地区作为植物区系和生物多样性的研究热点地区,长期以来极受中外植物学家关注。横断山脉东缘是中国-喜马拉雅和中国-日本植物区系的交汇过渡区域,北部的岷江流域以及南部的金沙江流域,孕育了该区丰富的物种资源和植被资源。而岷江干热河谷和金沙江干热河谷的相似性和相关性,更为该区的植物区系和生物多样性南北的对比研究提供了有利的条件。 本研究选择的九顶山西坡和龙肘山分别位于横断山区北部和南部,九顶山属岷江流域而龙肘山属金沙江流域。本研究结合植物区系研究和生物多样性研究,对该区的植物资源进行调查。通过样带调查和样线踏查结合,大量详实的野外样方调查和标本采集,进行传统的区系研究和生物多样性研究。研究该区物种多样性的海拔梯度格局及其潜在的影响影子,并利用新的区系评估质量方法对九顶山西坡的植物区系质量进行定量的研究,以期能更为深刻的理解该区的植物资源,为该区的资源保护和利用提供合理可行的建议。主要研究结论如下: 1)九顶山西坡植物区系的性质和特点 经鉴定和统计,九顶山西坡共有1707 种维管植物,分属617 属和140 科,其中种子植物1616 种,分属572 属117 科。就科的分布区成分构成而言,该区系的热带成分与温带成分相当,热带成分略占优势,表明九顶山西坡的植物区系与热带植物区系有较强的联系。但是,在九顶山西坡属的分布区类型所占的比例上,温带成分远远超过了热带成分,本区的种子植物分布表现出明显的温带性质。且温带分布类型的许多物种组成了九顶山西坡植被的建群种和优势种,是本区系最重要的成分,充分体现了本区系的温带性质。 2)九顶山西坡不同植被带的生物多样性海拔梯度格局 基于对土门-断头崖、茶山-九顶山、雁门沟-光光山三条垂直植被样带的调查,我们发现九顶山西坡的生物多样性沿海拔梯度的变化呈现出一定的规律性,不同样带之间有一定差异。就三条样带的物种组成相似性来看,虽然土门-断头崖样带属于涪江水系,而茶山-九顶山样带和雁门沟-光光山样带属于岷江水系,但不同水系对该区物种组成的影响并不明显。三条样带中,草本层物种丰富度均远远大于灌木层和乔木层,而以乔木层物种丰富度最低;α-多样性指数随着海拔梯度的变化在土门-断头崖样带中呈现单一下降趋势,在茶山-九顶山样带表现为双峰模型,而在雁门沟-光光山样带则表现为不显著波动变化;均匀度指数在土门-断头崖样带呈现出单一下降的趋势,在雁门沟-光光山样带表现为凹形曲线,而在茶山-九顶山样带却无明显的变化规律。β-多样性指数在土门-断头崖样带和茶山-九顶山样带呈现出明显的波动状态,植被类型替代现象明显;而在雁门沟-光光山样带却并未有十分显著的转折点,因其水平植被带受到干扰,同海拔替代现象不显著。 3)九顶山西坡维管植物丰富度的海拔梯度格局 我们考察了九顶山西坡和两条垂直样带(土门-断头崖和雁门沟-光光山样带)的不同分类等级(包括科、属、种)和不同生活型物种(乔木、灌木、禾草、蕨类和其它草本)的丰富度沿着海拔梯度的分布。结果发现,物种的丰富度海拔梯度格局具有不同的模式,单一下降和中间膨胀格局依然是其主流。不同生活型的物种具有不同的丰富度格局,但是对于环境需求相似的类型具有较相似的丰富度格局。不同的丰富度格局可能由多因素导致,包括:气候,海拔跨度,面积,人为干扰等等。 4)九顶山西坡区系质量评估 我们尝试使用传统的区系质量评估方法对九顶山西坡的区系质量进行评估,并尝试使用一种新的区系质量评估体系对该区的区系进行评价。在九顶山西坡随着海拔梯度的上升,平均保守性系数在各条植被带中均呈现出逐渐上升的趋势。区系质量指数随着海拔的升高都表现为双峰模型,在植被交错区区系质量指数相对较高,而在海拔的两极,区系质量指数都很低。大部分地区使用新方法计算所得的加权平均保守性系数和区系质量指数都比传统方法计算的平均保收性系数和区系质量指数要高,说明在九顶山西坡的三条样带中,大部分地区都是那些保守性系数较高的物种占据优势,同时也表明九顶山西坡具有很高质量的区系和自然植被。 5)龙肘山种子植物区系的性质和特点 龙肘山种子植物区系的物种较为丰富,共有154 科,544 属,1156 种。科的优势十分明显,单种属和寡种属数量众多,说明本区系植物成分较为复杂、起源古老、物种多样性指数较高。地理成分复杂,分布类型多样,其中热带成分在总数量上高于温带成分,但是许多温带成分的属是该区植被的重要建群类群和优势类群,表现出明显的亚热带性质。 6)龙肘山生物多样性的现状和特点 在海拔梯度上,龙肘山地区无论是科、属、种的数量,还是不同等级分类单元之间的数量比,均呈现先升后降的趋势,并在中海拔地区达到峰值。物种多样性指数从总体上来说变化幅度不大,略有先升后降的趋势,在中海拔梯度物种多样性最高。乔、灌、草三层的多样性指数表现出乔木层<灌木层<草本层的特征;乔木层均匀度的变化很大,而灌木层和草本层均匀度的变化较小;灌木层均匀度的波动又强于草本层。β-多样性指数呈现单峰模式,中海拔地区最高。就龙肘山东、西坡物种多样性相比较而言,两者虽然在数值上交替上升,但是却体现出了较为一致的趋势,但西坡因受到干热河谷气候的影响,其平均气温要高于东坡,导致了东坡植物群落和物种的分布比西坡要低。在区系成分构成上,低山区的相同海拔段,西坡的热带亚热带成分所占的比例要比东坡高,这是因为西坡的平均气温比东坡稍高,导致了热带、亚热带物种分布更多。而随着海拔的上升,东、西两坡的气候、土壤等条件趋于一致,其植物区系成分的构成格局也趋于一致。 The Hengduan Mountain region is a very natural floristic region; it belongs toChina-Himalaya sub-region of Holarctic region in floristic subarea of China. The flora in this areais rich in family, genus and species; has a very complex composition of geographical elements;especially with high richness of endemic species and obvious substitution phenomenon. Thisregion as a hot-spot area of floristic and biodiversity, has fascinated biologists in the world for along time. The eastern range of Hengduan Mountain is the transition zone of China – Himalayaforest sub-region and China-Japan forest sub-region in floristic. The water systems are quitedifferent, Minjiang River in the north and Jishajiang River in the south grow quit different but alsoabundant plant species and vegetation resources. The similarity and correlativity of Minjiang River dry valleys and Jinshajiang River dry valleys have provided advantageous condition tocontrast flora and biodiversity between north and south. In the present study, the Jiuding Mountainlies in the north of Hengduan Mountain and belongs to Minjiang River, and the LongzhouMountain lies in the south of Hengduan Mountain and belongs to Jinshajiang River. In our study, we combined the methods of floristic research and biodiversity investigation toexplore the resources of plant species and vegetations; sampled with transects along the altitudinalgradients and also with transverse straps with similar elevation; collected the vascular plant specimen with sampling plots of ecology. We explored the plant species richness patterns alongaltitudinal gradients and discussed the underlying factors aroused these patterns; and used a novelmethod to assess the quality of Jiuding Mountain’s flora. All for a deeper comprehension of the plant recourses of this region; and provided feasible and reasonable suggestion for the protectionof resources. The results were as follows: 1 The characteristic of the flora of the west slope of Jiuding Mountain We had collected 1707 species of vascular plants belonging to 617 genera in 140 families inthe west slope of Jiuding Mountain,in which included 1616 seed plant species belonging to 572genera and 117 families. As for the composition of the areal types of the Families of seed plants,tropic components and temperate components are well-balanced, and percentage of tropicscomponents is higher than that of temperate ones for a litter bit. This shows the flora in the westslope of Jiuding Mountain has strong relationship with the tropic flora. But for the composition ofthe areal types of genera, temperate components have far exceeded the tropics ones, indicated thewhole flora with a conspicuous temperate character. Temperate components possess maximumproportion in the west slope of Jiuding Mountain, and many of them belong to constructivespecies and dominant species in the vegetation, are most important components in JiudingMountain’s Flora, also have embodied the temperate character of this area sufficiently. 2 Biodiversity patterns along altitudinal gradients in different vegetation transects in the westslope of Jiuding Mountain Based on the investigation of three vegetation transects (including Tumen-Duantouya transect,Chashan-Jiudingshan transect and Yanmengou-Guangguangshan Transect) in the west slope ofJiuding Mountain, we found the change of biodiversity along the altitude gradients displayedcertain regularity, but have differences among different transects. The three transects belong todifferent water systems; the Tumen-Duantouya transect belongs to Fujiang River, and the othertwo belong to Minjiang River. From the similarity of species compositions of different transects,we found different water system didn’t show obvious impact on the species composition. In all thethree transects, the species richness of herb layer was remarkably higher than shrub and tree layer,and the species richness of tree layer was the lowest one. With the increasing of the altitude, theline of α-diversity was monotonically decreasing curve in Tumen-Duantouya transect, andbimodal curve in Chashan-Jiudingshan transect, but in Yanmengou-Guangguangshan transectshowed a wave-like curve although not very obvious. Species evenness showed monotonicallydecreasing trends in Tumen-Duantouya transect, and very low at mid-altitude in Yanmengou-Guangguangshan transect, but in Chashan-Jiudingshan transect changed irregularly. Changes inβ-diversity corresponded with the transition of vegetation in the Tumen-Duantouya transect andChashan-Jiudingshan transect, and the curve of β-diversity along altitude had obvious turningpoint; but in Yanmengou-Guangguangshan transect had no obvious turning point, and thesubstitution phenomenon was not obvious, transverse vegetation straps distributed interlaced. 3 Richness patterns of vascular plant species along altitude in the west slope of Jiuding Mountain Direct gradient analysis and regression methods were used to describe the species richnesspatterns along the altitudinal for Mt. Jiuding, as well as separately for Tumen-Duantouya Transectand Yanmengou-Guangguangshan Transect. Altitudinal gradient of diversity of units at differenttaxonomic level (including Family, Genus and Species) and at different life form (including tree,shrub, pteridophyte, grass and other herb) were tested to find differences among the richnesspattern. We found altitudinal richness also shows different patterns, and both monotonicallydecreasing pattern and hump-shaped pattern can be founded in vascular species richness. Speciesin different life forms show different altitudinal patterns, but those species with similarrequirements to environmental conditions show similar richness patterns along altitudinalgradients. Different richness patterns can be aroused by different climate, different altitudinal span,area factor, anthropogenic factor and so on. 4 Floristic quality assessments in the west slope of Jiuding Mountain We used both the conventional method broadly adopted in the USA and the new one toassess the floristic quality in the west slope of Jiuding Mountain. The Mean Coefficient ofConservatism (MC) had the trend of increment along the altitudinal gradients. The FloristicQuality Index (FQI) was a bimodal curve with increasing of elevation; FQI got maximum valuesin the transition zones of different vegetations in the middle altitude, and had very low values atthe two end of elevation. In most areas of the west slope of the Jiuding Mountain, the resultscalculated using the new methods were higher than those using the conventional method. Thisindicated the dominant species of the communities had very high coefficients of conservatism inmost areas of Jiuding Mountain, and the communities are relatively kept pristine and the habitats very integrative. 5 The characteristic of the flora of Longzhou Mountain The flora of Longzhou Mountain has very abundant in species composition; there are about1156 species of seed plants belonging to 544 genera in 154 families. In which, twelve families with more than 20 species include totally 232 genera and 532 species, and form the majority of itsflora. The origin of its flora is old, monospecific genera and oligotypic genera amounts to 510 innumber, which constitute 93.75% of total number of genera. The geographical components arevarious in Longzhou Mountain, the majority of flora are temperate and pantropic ones. The tropiccomponents overtopped temperate components on genera quantity, but many temperatecomponents belong to constructive species and dominant species in the vegetation, and the wholeflora shows an obvious subtropical character. 6 Current situation and characteristic of biodiversity in Longzhou Mountain With the increasing of altitude, the number of species, genus, family and the ratios ofdifferent taxonomic levels all displayed a trend of descending after rising first, and peaked atmiddle height area. The change of α-diversity was not very acutely, with the trend of descendingafter rising first in some degree, the middle height area had highest α-diversity. As studying thetree layer, shrub layer and herb layer respectively, the Shannon-Wiener index was in followingorder: tree layer < shrub layer < herb layer; the change of evenness was more complicatedly thanthat of diversity, the tree layer changed acutely, but the shrub layer and herb layer fluctuatedsmoothly. Changes in β-diversity also showed the trend of descending after rising first. TheJaccard index and Cody index all peaked at the middle height forest area. As for the comparison ofplant diversity and evenness between the west and east slope, the numerical values ascendedalternatively, but the trend of changing was similar. The distribution of similar plant communitiesand species in east slope were lower than the west slope for the influence of Jinsha River DryValley. As for the composition of different floristic components, in lower altitude area of westslope, the tropic and sub-tropic plants had higher ratio than east slope’s and even could be equal tothe temperate plants. With the increasing of elevation, the floristic composition become morelikely between the east and west slope and temperate plants dominated the flora.

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随着化工行业的发展,大量有毒有害难降解有机物随工业废水的排放进入环境,这些物质能够在环境中长期存在、积累和扩散,通过食物链对动植物的生存及人类的健康造成不良影响。本文以苯酚、对氯硝基苯、氯苯和十六烷为模拟污染物,以前期研制的功能菌剂为对象,经过紫外线线诱变筛选出优于出发菌株的功能菌,对诱变后功能菌的理化性能进行了研究,对菌种进行了鉴定,在此基础上,就其相互之间的微生态关系进行研究,为混合发酵提供理论基础,并就其最佳发酵条件及发酵参数进行了研究,最后对发酵产品的性能进行了检测。目前,国内外有关功能菌剂的研究还存在多方面的不足,主要包括:①由于多菌种混合发酵过程较为复杂,各菌之间存在复杂的相互作用,影响因素较多,关于菌种之间的相互关系研究得很少,环境功能菌剂的发酵方法大多采用单独发酵后混合的方式。单独发酵对原材料、设备和能源的利用率较低,对于多菌种制剂发酵,在设备、能源和原材料的方面造成的浪费更大,将会大幅增加菌剂的生产成本,影响多菌种功能菌剂的发展;②功能菌剂生产过程的质量控制方面研究得较少;③功能菌剂产品的稳定性、抗冲击性能研究得较少,对环境微生物制剂的研究主要集中在菌种选育和培养条件优化方面。 通过本论文研究,得到以下主要结论。 (1)在紫外线诱变处理中,用紫外线对发生一定程度退化的出发菌株进行诱变处理后,六株具有高效降解性能的菌株被筛选出来,诱变筛选出的菌株形态和ERIC-PCR指纹图谱与出发菌株相比发生了明显改变;而且诱变后的菌株对目标难降解底物的降解能力均得到改善,其中,FPN、FCB、F14、FEm对目标底物的降解率提高了20%以上;诱变后菌株经过7次连续传代接种后,对目标难降解底物的降解率无显著变化,具有一定的遗传稳定性。并对诱变后的功能菌进行了初步的鉴定,这6株菌都分别是芽孢杆菌。 (2)对诱变后的功能菌相互之间的微生态关系进行了研究,通过抑菌实验、生长量以及基质消耗量的比较,确定它们之间的生长关系是无害共栖关系,可以进行混合发酵。 (3)对该功能菌剂进行发酵培养条件研究,结果表明发酵培养基的最佳成分(g/L):葡萄糖 31.0g/L、玉米粉10.0g/L、磷酸氢二钾1.0g/L、硫酸铵1.1g/L、硫酸镁0.55g/L。通过研究不同的培养条件对菌体生长和降解性能的影响,确定了最佳培养条件:培养基初始pH7.5;最适温度32℃;培养基装液量125mL(250 mL三角瓶),以及培养时间对降解性能的影响,培养20 h的产物对降解最为有利。通过研究添加不同目标污染物对菌体生长和降解性能的影响,确定了添加目标污染物的最佳量以及最佳时间:苯酚投加量:1.125 g/L,对氯硝基苯投加量:0.1 g/L;最佳投加时间为发酵培养开始后4 h。 (4)以摇瓶分批发酵最优条件为基础,对FPN、F10、FCB、FNa、F14 和 FEm进行了摇瓶分批发酵试验。以摇瓶分批发酵试验数据为依据,对功能菌剂分批发酵动力学进行了研究,建立了菌体生长和基质消耗的动力学模型,拟合模型能较好的反映功能菌剂分批发酵过程。 (5)功能菌剂和活性污泥协同作用,可以提高系统的生物降解能力,功能菌剂投加量为2%,新鲜活性污泥3500 mg/L,降解24 h条件下,功能菌剂和活性污泥的协同作用对COD的去除率和对照组相比,最多的提高了36.8%。功能菌剂和活性污泥协同作用以及活性污泥的单独作用,其生物降解过程均符合一级反应动力学过程,功能菌剂和活性污泥协同作用的生物降解动力学方程为:,相关系数97%。采用SBR运行方式,引入功能菌剂的SBR系统明显能够改善和提高生物降解的效率。与仅有活性污泥的系统相比,系统对COD的平均去除率可以提高27.1%,同时,系统的耐负荷冲击以及耐毒害冲击的性能比仅有活性污泥的SBR系统强,特别是负荷冲击对引入功能菌剂的SBR系统影响很小。仅有活性污泥的SBR系统经过负荷冲击和毒害冲击之后,不能恢复到冲击之前的水平,而且系统有效作用时间的周期比引入功能菌剂的SBR系统相比大大缩短,而引入功能菌剂的SBR系统处理效果较为稳定,恢复能力很强。 Along with the development of industries, many recalcitrant organic chemicals have been discharged into natural environments together with wastewaters and can exist in waters, soil and sediments for a long time without degradation. These haz-ardous substances, their byporducts and metabolizabilities can be highly toxic, mu-tagenic and carcinogenic, thereby threatening animals, plants and human health through food chain. Consequently the removal of these compounds is of significant interest in the area of wastewater treatment. In this dissertation, the phenol, hydro-quinone, chlorobenzene and hexadecane treated as the model pollutants, the func-tional microorganism agent was used as the starting strains, they treated with ultra-violet light, and then the mutant strains with high degradation ability were screened out and identified primarily, the relationship between these stains were studied, the medium composition and fermentation conditions were optimized, the degradation ability of the fermented production was tested. The literature survey indicates that the study of the microorganism agent is far from complete and more information is re-quired on following problems. 1, Because of the complexity of relationship in mixed fermentation and the complicated factors, the study is hardly to process.2, There is a lack of information on the quality control of the producing process .3, And there is a lack of information on the stability about the microorganism agent. In this dissertation, the main results of the present study could be summarized as follows: (1)The degenerate starting strains were treated with the ultraviolet light, and six mutant strains with high biodegradation ability were screened out by using the me-dium with selective pressure of model pollutants. The mutant strains had great changes in colonialmorphology and ERIC-PCR fingerprinting. And the mutant strains got obvious advantages over the starting strains in degradation ability and over 20% improvement of removal rates was achieved for FPN、FCB、F14 and FEm. The de-gradation ability of the mutant strains was stable after seven generations. After that, the mutant strains were primarily identified as bacillus respectively. (2) The relationship between these mutant strains was studied. By the compari-son of antibiosis effect, biomass and consumption of substrate, the relationships were neutralism and they could be mixed fermented. (3) The optimized cultivation conditions were as follows: glucose 31.0 g/L, corn power 10 g/L, K2HPO4 1.0 g/L, (NH4)2SO4 1.1 g/L, MgSO4 0.55 g/L, initial pH7.5, temperature 32℃, working volume 125 mL/250 mL, and cultivation time 20h (con-sidering the time effect on degradation ability), adding pollutants phenol (1.125 g/L) and hydroquinone (0.1 g/L) into the broth at 4 h after cultivation. (4) Based on the above optimum condition, the batch fermentation was per-formed with strains FPN, F10, FCB, FNa, F14 and FEm in shake flask. The batch fermentation kinetics was studied based on the experimental data. Two kinetic models were constructed which could reflect the regularity of growth and substrate consump-tion in the process of batch fermentation. (5) The co-operation of functional microorganism agent and activated sludge could raise biodegradation of system by adding some microorganism agent and 3500 mg/L fresh activated sludge. Bioaugumentation by the addition of high effective deg-radation culture enhanced the treatment effect of SBR system and the COD removal rate was increased by 20%-36.8%. Its biodegradation matched first-order dynamical reaction equation, and the reaction equation was ln0.2327.391ct=−+. The micro-organism agent had the effect of optimization to activated sludge micro-ecosystem. The SBR system adding 2% microorganism agent, the average COD removal rate of that was increased by 27.1% and stronger anti-shock ability to load and toxicant were achieved (compared with SBR system just adding activated sludge). Especially the load-shock has barely effect to the SBR system adding microorganism agent. After the load and toxicant shock, the SBR system just adding activated sludge couldn’t come back to original level and the activated sludge micro-ecosystem was frustrated. The applying of microorganism agent increased biological activity and system’s re-sistance ability to load shock and toxicant shock.

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In this paper, the regularity and changes of the forest landscape along the major rivers, namely, Nuomin River,Bila River and Zhawen River in Daxing'an Mountains, Bilahe Forestry Bureau based on the interpretation of TM data were studied. The results showed that the regularity has changed a lot due to the gradually stronger human intervention on forest landscape. The most obvious change was the cultivated lands had been expanding alongside the major rivers. With the increasing of population, the only way to satisfy the increasing needs of the local people for subsistence is by expanding cultivated lands because of the backwardness of agriculture productivity. The regularity of conifer distribution along rivers of 1997 has changed in the diverse direction of that of 1988. The proportion of conifer gradually increases with 1 000 m further away from the major rivers. That is due to the favorable availability of conifer alongside river bank, the most populated area in the forest region.