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1.
纳米结构材料的制备及应用进展   总被引:1,自引:0,他引:1  
纳米结构材料表现出不同于传统块状材料的光、磁、声、电、催化等特性.如何实现纳米结构材料的可控制备及规模化应用,是当前纳米科技的挑战性问题之一.综述纳米结构材料的可控制备策略及应用探索,围绕晶面调控法、模板辅助法和物理场诱导法3种制备策略,以及在环境催化、能源和光学领域的应用研究,重点介绍课题组在纳米结构材料方面最新进展...  相似文献   

2.
电力现货市场中需协调调度输电网中可控资源实现对传输阻塞的缓解。考虑配电网中含有大量分布式电源以及可响应负荷,提出了以配电网公司作为主体参与电力现货市场阻塞管理的双层优化调度模型。输电网层以阻塞调度成本最小为目标,对各配电网公司的可控负荷和常规机组协同调度。配电网层以配电网电压波动和用户响应满意度为目标,在满足配电网安全约束的前提下,对配电网中资源进行协同调度。采用ATC算法对上下层模型进行求解,获取最优调度策略。最后对IEEE9节点的输电网和改进的两个配电网组成的输配全局电网进行仿真,验证所提方法的有效性。  相似文献   

3.
文中提出一种智能电网环境下可控负荷优化调度的双层优化模型.上层是可控负荷聚合器的优化问题,其目标是通过优化调度3类可控负荷的方式最小化购电成本;下层是电网优化问题,该问题提供电网实时电价给上层优化问题.文中将电网优化问题的KKT条件作为可控负荷优化问题的均衡约束,双层优化问题转换为具有均衡约束的数学规划(Mathematical Program with Equilibrium Constraints,MPEC)问题来求解.算例仿真反映了提出的调度策略的基本特征.  相似文献   

4.
融合型变电站作为集成建设多种功能站的新型运营模式,为边缘数据中心与电动汽车充电站的规划运行提出了新的方向;而作为典型的综合能源系统,其运行优化方法也有待深入研究.针对融合型变电站内各功能站协同优化问题,设计了涵盖数据中心、储能电站、电动汽车充电站的融合型变电站运行架构,建立了以年净支出最小为目标函数的多站协同运行优化模型,提出了融合型变电站优化运行策略.通过模型的优化求解,确定多站协同运行最优方案.算例结果表明:电动汽车充电站负荷曲线具有明显的峰谷特性,且与电网用电高峰时段相符,电动汽车充电站接入融合型变电站会进一步加剧供电压力;通过信息负荷与储能电站的灵活调度,可以实现电力负荷在时间与空间上的转移,达到转移高峰负载、促进电动汽车平滑入网、显著降低运行成本的效果;融合型变电站的日净收益随低时延数据负荷的比例增大而增大,二者近似呈线性关系.  相似文献   

5.
综合考虑调控操作前后电网运行风险的差异,将电网调控操作风险指标定义为操作前后系统运行风险指标的变化量并引入风险理论,提出一个考虑指数型操作人员实时综合因子的风险差分运算电网调控操作的量化风险指标体系. 基于局部潮流量化分析的调控操作关键影响设备搜索技术,用于快速定位受影响较大的敏感节点及支路,缩小风险分析范围. 采用基于局部拓扑相关性分析的调控操作事故集筛选技术,以关键设备为搜索中心筛选出与调控操作相关度较高的事故集,实现事故集范围的可控化,有效提升计算效率. 该指标体系体现了电网调控操作的实质是系统运行状态的变化,而非某一特定系统运行状态,能够从本质上反映调控操作对电网产生的影响,最后结合多个算例验证所提方法的有效性.  相似文献   

6.
针对配电网发生故障时的失电负荷恢复供电问题,总结归纳了含分布式电源、电动汽车和储能等可控负荷参与、抢修任务分配以及多代理设计等故障修复策略的研究进展,并从故障抢修、故障恢复以及故障抢修与恢复协同优化策略等3个方面的研究成果进行了论述,指出了目前在该领域的研究进展及尚且存在的问题与不足,并对今后的研究方向提出了建议。  相似文献   

7.
本文分析了当前科技发展及电力系统实验研究对于可以精确模拟各种负荷特性及综合负荷特性的装置的需求及该装置的重要性,并在分析传统可控负荷特性模拟实验装置缺陷的基础上,提出了利用电力电子器件实现可控负荷特性模拟功能的装置的主电路拓扑结构。该电路由整流变压器、PWM高频整流H桥模块、放电支路、高频H桥模块、低频级联H桥模块、高频连接电抗和低频连接电抗组成,能有效模拟谐波电流发生、电流波动和负荷电流不平衡,并能模拟各种复合扰动。  相似文献   

8.
混合储能具有良好的功率可控特性,在孤岛微网中常被用作功率缓冲器,补偿分布式电源和负荷多变的功率潮流.围绕储能的功率响应问题,本文设计了混合储能的功率控制方案,并提出了一种基于多目标协调的子单元功率自适应分配方法.首先基于对母线功率供求平衡关系的分析,设计了主从并联型储能功率控制方案.其次利用积分器的“时空调零”特性,实现了子单元的功率自主分配;基于此,考虑了不同荷电状态(SOC)下储能最大充放电功率的差异,设计了子单元的SOC分层管理和多目标功率协调策略.仿真结果表明,所提策略实现的功率分配效果满足子单元的功率响应特性;随着超级电容SOCscn偏移加深,所提策略对SOCscn的优化能力越强,初始SOCscn为97%时能提高10.10%的优化性能,这保障了超级电容作为电压源的功率输出能力;所提策略降低了超级电容常态下的蓄电池的输出深度,蓄电池的最大功率深度降低了46.70%,这提高了蓄电池的使用寿命.  相似文献   

9.
随着后摩尔时代的推进,以硅为基础的半导体器件正接近其性能极限.除了不断引入新的器件结构外,设计具有半导体特性的金属量子结构为微电子器件的性能提升提供了全新的解决方案;而打开金属带隙,使其具有栅极可调半导体输运,是实现其应用的关键.以此为目的,自20世纪末以来,多种金属量子结构便逐步被设计与开发,其输运特性的有效调控也被学术界广泛研究.本文回顾了零维量子点、一维纳米线/纳米管、二维材料/人工二维晶格/超导薄膜等不同维度金属量子结构的研究进展;针对这些结构体系,介绍了其各自的能隙调控思想,总结分析了可控输运特性的实现方法与内在机制,对比展示了材料结构的电学性能及应用前景.基于目前报道的研究结果,提出了未来预期的研究方向:开发金属量子结构中输运与自旋关联特性,设计同时传输电荷与自旋信息,且具有栅极可调输运带隙的全金属沟道材料、结构与器件.  相似文献   

10.
受较大计算负荷的影响,传统的电网分析软件已经不能够满足现代电网系统的需求,对电网安全稳定特性分析有所欠缺,因此必须对其进行有效改进。此次研究将实现多层级电网年度运行方式的协同分析作为目标,探究了多层级电网基础数据管理平台,并在此基础上构建了多层级电网协同分析集成系统,促进电网年度运行方式编制工作的协同运作和高效运转。  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.
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   

16.
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   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
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   

20.
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   

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