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1.
胡奇  郑莉 《山西科技》2008,(2):104-106
文章应用LCA(生命周期评价)方法尝试对水泥混凝土和粉煤灰混凝土两种路用材料进行评价,评价结果表明在水泥混凝土中掺入粉煤灰可以提高混凝土的环境协调性.同时也指出了路用材料LCA局限性及其改进的方向.  相似文献   

2.
能源系统生命周期清单分析数据库是产品或系统生命周期评价的基础,由于我国能源生产过程的基础数据种类繁多且更新较快,能源上游清单数据库需要考虑时间有效性的影响.结合单因素敏感性分析和参数自身时效性分析的方法筛选出10个对主要能源系统生命周期碳排放影响较大的时间敏感参数,并进行更新时间间隔划分.此方法可以减少生命周期评价数据库维护工作量,也为提高产品或系统生命周期评价的可靠性打下基础.  相似文献   

3.
基于生命周期评价的桥梁环境影响对比分析   总被引:1,自引:0,他引:1  
提出了桥梁生命周期环境影响评价和对比分析方法,对于不同桥梁的环境影响评价结果采用单位桥长法和单位原材料法进行修正,并应用于武汉市墨水湖大桥和南太子湖大桥.结果表明,在建筑材料生产过程和桥梁施工过程中固体废弃物环境影响最大,在桥梁运营维护过程中全球变暖环境影响显著,南太子湖大桥施工方法较墨水湖大桥更为环保.  相似文献   

4.
无线传感器网络资源有限,传感器节点之间节点的能量消耗不均衡,使得整体网络生命周期缩短.针对无线传感器网络数据收集过程中能量消耗不均衡的问题,给出一种基于能耗均衡高效的数据收集算法.该算法将网络部署区域划分为大小不等的栅格,并根据节点剩余能量以及采用簇首轮换的方式,然后采用数据融合技术,可以有效提高节点能量消耗均衡度且可以大大延长网络寿命.仿真与性能分析结果表明:与典型数据收集算法相比,该算法在能耗均衡度和网络生命周期方面具有更好的性能.  相似文献   

5.
再制造发动机被公认为节能、节材、经济和环保,是实现循环经济和可持续发展的一种重要手段.生命周期评价(LCA)是一种评估产品从原材料开采、运输、制造、用户使用到最终处置的潜在环境影响的方法.系统研究了排放标准对再制造发动机环境效益的影响,并分析了跨标准阶段使用情景下的环境损伤.针对跨标准阶段再制造原型机的环境损伤问题,提出了两种解决方案,并分析了两种升级再制造方式对环境的影响.结果表明:跨标准阶段使用的再制造原型机会增加环境影响.两种升级再制造方法可以弥补排放标准的限制:油改气方法的能源消耗高,环境性能好;安装后处理设备会增加资源消耗,臭氧层破坏潜值显著增加,但其他环境指标将减少.  相似文献   

6.
生命周期评价软件系统平台的模块设计与实现   总被引:5,自引:0,他引:5  
本文在汲取国外优秀生命周期软件的设计思想,运用面向对象软件开发的基本原理,根据GB24040生命周期评价系列标准,提出了一种生命周期评价软件系统的设计方法并介绍了生命周期评价软件系统的设计与实现.该系统实现了生命周期清单数据的读入写出、清单数据和评价数据的数据库管理,有功能丰富的生命周期清单分析和影响评价算法和操作以及方便的人机交互界面.  相似文献   

7.
机械CAD系统选型时面临信息不对称、缺乏客观依据等问题.分析了面向产品生命周期(PLC)的CAD系统好产品设计过程;建立面向产品生命周期的机械CAD系统评价,包括对产品生命周期过程实现的广度、深度,对全生命周期数据流的支持两个维度;提出采用模糊评价方法进行评价.实例证明,评价体系和方法可以实现机械CAD系统的合理选择.  相似文献   

8.
王仁红 《科技资讯》2014,(14):119-119
随着我国经济的快速发展,工业化发展给人们的生活带来了很大的变化,但同时,在工业化发展的过程中,环境污染问题日益严重,人们越来越重视绿色环保问题。绿色环保理念应用于工业设计中,可以提高工业产品的环保性能,因此本文详细介绍了绿色环保理念下工业设计的基本含义,分析了环保理念在工业机械设计中的重要性,从而转变工业机械的设计思路,提高工业机械产品质量。  相似文献   

9.
对市场上常见的较厚塑料购物袋与其替代品——环保纺织品购物袋(无纺布袋、棉布袋)及牛皮纸袋的机械性能进行数据测试,并进行试验结果讨论、分析。针对目前我国国情对塑料袋替代品发展提出一些建议。  相似文献   

10.
汽车燃料的生命周期评价模型   总被引:10,自引:0,他引:10  
以国际标准化组织的生命周期评价标准为依据 ,确定了汽车燃料生命周期清单分析参数和评价边界 ,提出了燃料上游阶段清单的计算逻辑 ,给出了模型的主要计算公式 .对氢燃料生命周期和汽油燃料生命周期进行了清单计算和结果比较 ,发现制氢方案是影响燃料电池车的燃料生命周期环境性能的关键 ,天然气制氢和石脑油制氢的氢能供应方案能使燃料电池车的燃料生命周期环境排放比汽油车低  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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