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1.
基于一类不可逆三热源热泵的循环模型,以每单位时间成本的泵热率作为热经济学目标函数,研究投资成本、供热成本、其它费用成本和几种主要不可逆性对热泵优化性能的影响,计算了热经济学目标函数的最大值及对应的各种性能参数,确定了三热源热泵的最佳工作区域和重要参数的性能界限。  相似文献   

2.
基于内可逆三热源热泵的有限时间热力学理论和太阳能集热器的线性热损模型,研究太阳能热泵系统的优化性能,导出太阳能集热器的最佳工作温度、系统的最大总性能系数和最大泵热率,并指出现有文献中有关这类研究的错误,所得结果可为实际太阳能热泵系统的优化设计提供一些新的理论依据。  相似文献   

3.
线性唯象律下三热源热泵的Yong经济优化性能   总被引:6,自引:0,他引:6  
研究线性唯象律下三热源热泵的Yong经济优化性能,并揭示了它与生态学优化性能间的内在联系,同时还对热泵的合理工作区作了有意义的讨论。  相似文献   

4.
线性唯象律下三热源热泵的火用经济优化性能   总被引:2,自引:0,他引:2  
研究线性唯象律下三热源热泵的火用经济优化性能,并揭示了它与生态学优化性能间的内在联系,同时还对热泵的合理工作区作了有意义的讨论  相似文献   

5.
本文在内可逆循环模型基础上,进一步考虑除热阻以外的其它不可逆效应,建立不可逆三热源热泵泵热循环模型,导出其最佳供热系数和供热率间的关系,从而阐明这种方法不仅对不可逆二热源热泵适用,对三热源热泵也同样适用。  相似文献   

6.
一类三热源制冷机的生态学优化准则   总被引:7,自引:0,他引:7  
以生态学准则函数为目标,研究一类三热源制冷机的优化性能.导出制冷机的一些新性能参数,为制冷机的最佳工况选择提供了一个新方案,对制冷机的优化设计有指导意义.  相似文献   

7.
薛浩 《江南学院学报》2000,15(4):63-66,94
在内可逆循环模型基础上,进一步考虑除热阻以外的其它不可逆效应,建立不可逆三热源热泵循环模型,导出其最佳供热系数和供热率间的关系,从而阐明这种方法不仅对不可逆三热源热泵适用,对三热源热泵也同样适同。  相似文献   

8.
在内可逆循环模型基础上 ,进一步考虑除热阻以外的其它不可逆效应 ,建立不可逆三热源热泵循环模型 ,导出其最佳供热系数和供热率间的关系 ,从而阐明这种方法不仅对不可逆三热源热泵适用 ,对三热源热泵也同样适同。  相似文献   

9.
Q∝Δ(T^n)时广义不可逆卡诺热机的生态学性能优化   总被引:1,自引:0,他引:1  
以反映热机功率与熵产率之问最佳折衷的“生态学”准则为目标,根据生态学优化方法研究传热规律服从Q∝Δ(T^n)时不可逆卡诺热机生态学最优性能.在内可逆模型基础上,用常数项q表示热漏流率,用常数项Φ表示除热阻和热漏以外的其余不可逆性,导出了传热规律服从Q∝Δ(T^n)时广义不可逆卡诺热机生态学优化性能.通过数值计算对不同损失、不同传热规律情况下的热机生态学性能变化规律进行了比较分析,本文结果对实际热机的设计工作具有一定的理论指导意义.  相似文献   

10.
关于热力循环生态学优化准则   总被引:7,自引:1,他引:7  
强调了热力循环生态学优化准则的基本思想是使热力循环的功能率与功能率耗散达到最佳的折衷,并讨论了导热规律为q∝△(1/T)时卡诺热机的生态学优化准则.此外还纠正了有关研究中的错误.  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.
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   

15.
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   

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.
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   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  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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