46 resultados para Industrial wastes recycling
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本论文以红薯淀粉的双酶法水解液为碳源,从19 株红色酵母中筛选出一株油脂含量较高的菌株掷孢酵母(Sporobolomyces reseus)As.2.618。为了提高掷孢酵母(S.reseus)As.2.618 的油脂产量,考察了培养基组成对该菌生长情况及油脂积累的影响。用均匀设计法对培养基组成进行了优化,由DPS软件得出的优化结果为:还原糖103g/L、酵母粉11.5g/L、磷酸二氢钾0.3g/L、硫酸镁0.15g/L。生物量可达19.23 g/L,油脂含量为3.875 g/L。研究了添加二价离子对该菌的生长及油脂积累的影响,结果表明Zn2+对该菌生长和油脂积累都有显著促进作用。研究了发酵条件以及添加氧载体正十二烷对该菌发酵的影响,表明添加正十二烷有利用于该菌生长与油脂积累。得出最佳发酵条件是:在还原糖103g/L、酵母粉11.5g/L、磷酸二氢钾0.3g/L、硫酸镁0.15g/L。添加30mg/L 硫酸锌,接种量为5%,在24h 后添加2g/L 的碳酸钙和2%(v/v)正十二烷,pH6.0 培养温度为27℃,转速为200r/min,培养时间为7 天的条件下,该菌生物量干重可达35.05g/L,油脂含量也达11.98g/L。Lipid is one of the basic material for life-sustaining activities andimportant industrial materials. As lipid resources mainly come from the animal andthe plant, the problem of lipid lack is encountered at times. The lipid frommicroorganisms is the substitute and superior to the above lipid with a short period ofproduction and much cheaper fermentation materials such as agricultural and sidelineproducts or wastes of crop.Thus large scale production and broad application ofmicrobial lipid will be efficient not only in substitute of the animal and the plant lipidfor food and industrial field , but also inducing a new way leading to solve the energyproblem.For the purpose of exploring the characteristics of lipid production of redyeasts from sweet potato starch hydrolysates. 19 red yeasts are screened for thecapability of lipid producing and one strain Sporobolomyces reseus As.2.618 withsuperior performance is sellected.To improve the Sporobolomyces reseus As.2.618’s capability of lipidaccumulation , the components of the medium, which may influence the growth of thestrain and the lipid yield have been studied. To get the optimum mediumcomponents ,the “uniform design” was used .The DPS software gave the optimummedium component is: reducing sugar 103 g/L、yeast extract 11.5 g/L、KH2PO4 0.3g/L、MgSO4 0.15 g/L. The biomass could reach up to 19.23 g/L and lipid yield 3.87g/L with the above composition of fermentation medium.Furthermore the fermentation conditions , addition of the divalent metal ionsand the oxygen vector to increase the strain’s lipid producing capability are tested.The optimum condition is : reducing sugar 103 g/L、yeast extract 11.5 g/L、KH2PO40.3 g/L、MgSO4 0.15 g/L,Adding 30mg/L ZnSO4,and adding 2g/L CaCO3 2%(v/v)n-dodecane after 24h’s fermentation. the optimal fermentation condition were asfollow :30ml medium in the 500ml flask with initial pH 6.0,the flasks with 5%inoculation volume were at 200r/min shaking speed for 7d’s fermentation at27 .Under this kind of condition the high biom ¡æ ass which reach to 35.05 g/L could begot ,the yield of lipid also could reach to 11.98g/L.
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IEECAS SKLLQG
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Variation in dinoflagellate cyst assemblages through the last approximately 300 years was studied in two sediment cores, one from the heavily polluted Frierfjord, and one from the adjoining, relatively unpolluted Brevikfjord, in order to docu1ent possible dinoflagellate responses to pollution. Changes in the cyst-flora were compared with historical information on the development of industry and also with geochemistry of the sediments, reflecting aspects of pollution. In the Frierfjord core, increasing pollution was accompanied by a decrease in cyst concentration, possibly reflecting reduced production, at least of dinoflagellates, and a shift toward more heterotrophic species, possibly reflecting reduced light penetration in the euphotic zone, or increased production of prey for the heterotrophs. These trends seem to have reversed as pollution decreased after about 1975, suggesting that cyst assemblages contain signals that may prove useful for tracing the development of pollution. Cyst assemblages in the Brevikfjord core only showed minor changes.
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Association for Computing Machinery, ACM; IEEE; IEEE Computer Society; SIGSOFT
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The interactions among industrial development, land use/cover change (LUCC), and environmental effects in Changshu in the eastern coastal China were analyzed using high-resolution Landsat TM data in 1990, 1995, 2000, and 2006, socio-economic data and water environmental quality monitoring data from research institutes and governmental departments. Three phases of industrial development in Changshu were examined (i.e., the three periods of 1990 to 1995, 1995 to 2000, and 2000 to 2006). Besides industrial development and rapid urbanization, land use/cover in Changshu had changed drastically from 1990 to 2006. This change was characterized by major replacements of farmland by urban and rural settlements, artificial ponds, forested and constructed land. Industrialization, urbanization, agricultural structure adjustment, and rural housing construction were the major socio-economic driving forces of LUCC in Changshu. In addition, the annual value of ecosystem services in Changshu decreased slightly during 1990-2000, but increased significantly during 2000-2006. Nevertheless, the local environmental quality in Changshu, especially in rural areas, has not yet been improved significantly. Thus, this paper suggests an increased attention to fully realize the role of land supply in adjustment of environment-friendly industrial structure and urban-rural spatial restructuring, and translating the land management and environmental protection policies into an optimized industrial distribution and land-use pattern.
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随着全球生态环境的恶化,各国日益重视对水体中各种污染物的治理。利用藻类的吸收、富集和降解作用,可以去除污水中的营养物质、重金属离子和有机污染物,与其他物理、化学及工程的方法相比,该技术具有以下优点:成本低、能耗小、治理效果较好,对环境污染小,有利于资源化,有利于整体生态环境的改善,是治理水质污染的新途径。 本文利用几种大型海藻对富营养化海水进行处理,结果发现孔石莼、刚毛藻均有很强的吸收N、P的能力,吸收能力依次为褶曲刚毛藻>束生刚毛藻>孔石莼。水体中褶曲刚毛藻3 g/L含量,在3~5小时之内,可把中等以上富营养化海水中的N、P降低至一类海水水平。利用刚毛藻处理富营养化地下海水和养殖废水,进行海参和大菱鲆养殖试验,探索藻类净化水质和废水循环利用的新模式,使水体保持较低的营养盐状态,减轻养殖废水对环境的影响,实现了海水养殖业与环境的可持续发展。 刚毛藻在我国近海滩涂分布广泛,利用它来处理富营养化水体,并和水产养殖业相结合,既净化水体,使养殖废水能循环利用,满足水产养殖的需求,又改善水产业生态环境。同时,将回收藻体生产优质饲料、食品和药物等,实现藻类资源的高值利用。刚毛藻营养丰富,用其替代鼠尾藻作海参饲料,资源丰富,成本低,效果好,是一种值得加以开发利用的宝贵资源,具有广泛的应用前景。 生物吸附法是一种经济有效的移除废水中有害重金属离子的方法。由于藻类细胞壁中的多聚糖可提供吸附重金属的位点,廉价而蕴藏丰富的海藻对多种重金属表现出很强的吸附能力。所以本文通过分批实验,研究了非活体刚毛藻对水体中重金属Cu2+、Pb2+和Cd2+的吸附影响因子、吸附热力学、吸附动力学及吸附机理,得到了平衡等温线及动力学数据。吸附过程的最佳pH值为5.0,吸附量随温度的升高而增加,水体中常见的Na+、K+、Ca2+、Mg2+阳离子及Cl-、NO3-、SO42-、C2O42-等阴离子的存在对吸附的影响并不显著。EDTA存在时,吸附百分率大大降低。吸附等温线符合Langmuir和Freundlich方程。刚毛藻对重金属Cu2+、Pb2+和Cd2+的吸附容量很高,25℃时,对Cu2+、Pb2+和Cd2+的最大吸附容量分别为1.61 mmol/g、0.96 mmol/g和0.98 mmol/g,且吸附过程为吸热反应。刚毛藻对重金属Cu2+、Pb2+和Cd2+的吸附过程为化学吸附,在吸附过程中藻体表面的官能团可能与金属离子发生了螯合作用。吸附动力学过程符合pseudo-二级动力学模型,在初始的30min内,吸附速率很快,随后速率逐渐降低。解吸试验表明,用EDTA可以对重金属进行回收,刚毛藻可以循环利用。实验结果表明刚毛藻是一种高效、经济实用的生物吸附材料,可用来吸附回收水体中的重金属Cu2+、Pb2+和Cd2+等。 通过非活体刚毛藻对重金属Cr6+的吸附影响因子、吸附动力学、吸附机理的研究发现,刚毛藻对Cr6+具有很强的还原能力,对电镀废水中的Cr6+的还原去除提供了非常好的方法。吸附过程的最佳pH值为2~3,实际电镀废水通常在此pH范围,因此处理实际废水时,首先在原酸性条件下,对Cr6+进行还原去除,然后调废水pH至5.0,继续进行吸附,去除其他二价离子及被还原的三价Cr离子,实现了利用同一材料还原Cr6+为Cr3+,并将Cr3+和其他重金属离子同时去除。通过对机理的讨论,认为刚毛藻对Cr6+的生物吸附过程不是一个简单的“离子交换过程”,而是一个“吸附还原过程”。在海藻量足够的前提下,只要时间足够长,Cr6+可被彻底还原去除。 利用工业废弃物褐藻渣,对水体中重金属离子Cu2+、Pb2+、Cd2+及Cr6+的生物吸附特性分别进行了讨论,结果表明褐藻渣对重金属离子的吸附特性与刚毛藻一致,吸附等温线符合Langmuir和Freundlich方程,在25℃时,pH为5.0时,由Langmuir方程求出褐藻渣对Cu2+、Pb2+和Cd2+的最大吸附容量分别为4.20 mmol/g、3.13 mmol/g和2.97 mmol/g。褐藻渣对低、高浓度的重金属Cr6+都具有很强的吸附能力,且移除效果比较彻底。实际应用结果表明,褐藻渣是一种高效、经济实用的生物吸附材料,可用来吸附回收水体中的重金属离子,具有广泛的应用前景。
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提出了一种用于工业机器人时间最优轨迹规划及轨迹控制的新方法,它可以确保在关节位移、速度、加速度以及二阶加速度边界值的约束下,机器人手部沿笛卡尔空间中规定路径运动的时间阳短。在这种方法中,所规划的关节轨迹都采用二次多项式加余弦函数的形式,不仅可以保证各关节运动的位移、速度 、加速度连续而且还可以保证各关节运动的二阶加速度连续。采用这种方法,既可以提高机器人的工作效率又可以延长机器人的工作寿命以PUMA560机器人为对象进行了计算机仿真和机器人实验,结果表明这种方法是正确的有效的。它为工业机器人在非线性运动学约束条件下的时间最优轨迹规划及控制问题提供了一种较好的解决方案。
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Geopolymer gelatinous material was prepared by ferroalloy slag (signed with NKT in laboratory) and circulating fluidization bed slag (CFB slag, signed with NM in laboratory) produced from Heshan city, Guangxi zhuang autonomous region, China. The mechanical properties of the geopolymer made of high content ferroalloy slag can reach the standard of 42.5# portland blastfurnace-slag cement, and it’s processing technology is more simple and not need of mill and burn and will not produce harmful gas. By means of chemical and XRD analyses, it is concluded that NKT is a kind of acidity water-granulated slag with better activation and fit to be activated by alkali activators. Low-cost industrial gypsum (signed with NG in laboratory), analytic reagent oxide(signed with NH in laboratory) and sulfate(signed with NS in laboratory) were selected as alkali activation in the experiment. The results showed NH is a good alkali activator for NKT. Both NH and NG can activate ferroally slag’s activities, but NS can’t alone. The activation effect of superimposing activation of NH and NG excel by separateness. Based on those experiments, optimization compounds were carried out: (1) NKT: NH: NG = 80: 10: 10 and (2) NM: NKT: NS: NG: NH = 10: 70: 2: 8: 10。. The soundness of the test blocks is good by boiling examination. Through XRD, SEM, IR, NMR analyses of geopolymer, the reaction mechanism of geopolymer prepared by alkalescent activating in solid wastes was discussed in the thesis first. It is point out, there is difference in reaction mechanism between traditional geopolymer preparation and the preparation of alkalescent activating solid wastes because NG is a industry product. There is the similar process of depolymerization and reunion of Si-O bond. The latter preparation process generate new subtance but the former doesn’t. In the experiment, we found a performance of NKT that the water requirement of normal consistency of geopolymer reduces with increasing content of NKT. The result shows NKT has some ability to reduce water requirement. The performance is worthy of further research and utilization. Making use of solid wastes to prepare geopolymer, not only can settle environment problem caused by a great deal of dump of NKT, but also settle the shortage of natural resources. Moreover it could take economic, environmental and social benefits and settle thoroughly contradiction in the environment protection and regional economy development and promote circulation economy development.
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Based on a viewpoint of an intricate system demanding high, this thesis advances a new concept that urban sustainable development stratagem is a high harmony and amalgamation among urban economy, geo-environment and tech-capital, and the optimum field of which lies in their mutual matching part, which quantitatively demarcates the optimum value field of urban sustainable development and establishes the academic foundation to describe and analyze sustainable development stratagem. And establishes a series of cause-effect model, a analysissitus model, flux model as well as its recognizing mode for urban system are established by the approach of System Dynamics, which can distinguish urban states by its polarity of entropy flows. At the same time, the matter flow, energy flow and information flow which exist in the course of urban development are analyzed based on the input/output (I/O) relationships of urban economy. And a new type of I/O relationships, namely new resources-environment account, are established, in which both resource and environment factors are considered. All above that settles a theoretic foundation for resource economy and environment economy as well as quantitative relationships of inter-function between urban development and geoenvironment, and gives a new approach to analyze natinal economy and urban sustainable development. Based on an analysis of the connection between resource-environmental construct of geoenvironment and urban economy development, the Geoenvironmental Carrying Capability (GeCC) is analyzed. Further more, a series of definitions and formula about the Gross Carrying Capability (GCC), Structure Carrying Capability (SCC) and Impulse Carrying Capability (ICC) is achieved, which can be applied to evaluate both the quality and capacity of geoenvironment and thereunder to determine the scale and velocity for urban development. A demonstrative study of the above is applied to Beihai city (Guangxi province, PRC), and the numerical value laws between the urban development and its geoenvironment is studied by the I/O relationship in the urban economy as following: · the relationships between the urban economic development and land use as well as consumption of underground water, metal mineral, mineral energy source, metalloid mineral and other geologic resources. · the relationships between urban economy and waste output such as industrial "3 waste", dust, rubbish and living polluted water as well as the restricting impact of both resource-environmental factors and tech-capital on the urban grow. · Optimization and control analysis on the reciprocity between urban economy and its geoenvironment are discussed, and sensitive factors and its order of the urban geoenvironmental resources, wastes and economic sections are fixed, which can be applied to determine the urban industrial structure, scale, grow rate matching with its geoenvironment and tech-capital. · a sustainable development stratagem for the city is suggested.
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Distributions of elements especially hazard trace elements in coals and their wastes from a coal fired power plant have been studied in detail using knowledge of Geology, Mineralogy, Geochemistry and Environmental chemistry. The key work is on the small particle sizes of fly ashes which escaped from electric precipitator and discharged into atmosphere. By means of X-ray powder diffraction (XRD) and scanning electron microscopy with energy-dispersive spectrometer (SEM-EDS), the characteristics of minerals and morphologies were studied. Different types of fly ash were formed in different stages and processes. More than 50% of small fly ashes belonged to inhalable particles (PM10). The very fine fly ashes preferred to attach on surface of bigger fly ash or conglutinate with each other and this decreased the environmental impact of tiny fly ashes. The trace elements in coal, fly ashes, slags and small particle sizes of fly ashes had been analysed by means of Neutron Activation Analysis (INAA), inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma atomic emission spectrometry (ICP-AES). As particle sizes decreasing, distributions of most elements increased, but in contrary to most studies, this increasing trend was not very obviously because of the tendency of attachment of tiny fly ashes. The occurrence of 30 elements including hazard trace elements of Cd, Cr, Ni, Co, Pb, Zn, As, Se, Cu, V was studied by means of sequential chemical extract. The annual discharge of hazard trace elements of slag, fly ash, small fly ash (PM10), tiny fly ash (PM2.5) and air was calculated by mass balance. S, V, Cu, Pb, Se, Mo, Cd from power plant had potential impacts on environment. Hazard trace elements from the power plant had little effect on soil and aerosol comparing to those from other industrial sources and the effects were mostly on downwind direction. Both the high performance electric precipitator and high chimney made the hazard trace elements from power plant being transported far away but little environmental impacts.
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An industrial scale dehydration process based on hollow fiber membranes for lowering the dew point of natural gas is described in this paper. A pilot test with the feed flux scale of 12x10(4) Nm(3)/d was carried out. Dew points of -8 degreesC-13 degreesC at a gas transport pressure in the pipeline of 4.6M Pa and methane recovery of more than 98% were attained. The water vapor content of the product gas could be maintained around 0.01 vol% during a continuous run of about 700 hours. The effects of feed flux and operation pressure on methane recovery and water vapor content were also investigated. Additionally, some auxiliary technologies, such as a full-time engine using natural gas as fuel and the utilization of vent gas in the process, are also discussed. A small amount of the vent gas from the system was used as a fuel for an engine to drive vacuum pumps, and the heat expelled from the engine was used to warm up the natural gas feed. The whole system can be operated in a self-sustainable manner from an energy point of view, and has a relatively high efficiency in the utilization of natural gas.