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391.
产品绿色设计评估建模   总被引:7,自引:0,他引:7  
绿色设计评估是实施产品绿色设计的关键技术。建立了产品的全生命周期信息模型 ;并在此基础上 ,提出了退役产品的拆卸回收评估方法和产品全生命周期环境影响评估方法 ;探讨了产品绿色设计决策支持系统的框架组成。绿色设计评估系统将产品的拆卸回收分析和产品全生命周期分析结合在一起 ,可为产品的绿色设计提供方案评估和决策支持  相似文献   
392.
Among the various xenoliths entrained by the Cenozoic Hannuoba basalts, peridotite is the most abundant one. The trace elements of the diopsides from the peridotite xenoliths were analysed by LA-ICP-MS. The overall depletion and some heterogeneity of the continental mantle beneath northern North China Craton were indicated by the characteristics of the trace elements. The ∑REE amount in diopside correlates with the Cr/(Cr+Al) ratio of diopside which is indicative of xenolith's partial melting degree. As the peridotite hosts and pyroxenite veins show similar REE distribution patterns, the composite xenoliths are probably formed by mantle deformation, rather than by the late metasomatism of mantle fluids/melts.  相似文献   
393.
浅谈药学专业学生在开放式实验教学中的实践与效果   总被引:2,自引:0,他引:2  
本文旨在开放实验教学中,通过学生自己查找资料、采购原料、自主设计实验等方式,探讨开放实验教学对激发学生探索知识的积极性、培养学生的实验动手和与社会接触能力、提高学生的创造思维和科研能力、促进学生综合素质发展等重要作用。  相似文献   
394.
阐述了信息环境的发展、信息用户行为与需求变化、经济发展与图书馆自身业务发展需求等共同构成了高校图书馆服务创新的驱动力,分析了服务理念滞后及信息资源、技术、人才缺乏等因素对高校图书馆服务创新的制约,指出高校图书馆应从服务理念、服务形态、服务技术、服务内容、人才资源等方面进行创新。  相似文献   
395.
香港政府在打击贿赂犯罪方面有着自己独特的手段与方法,为经济的发展提供了强有力的保障。通过介绍两地的立法情况,比较分析贿赂犯罪的构成,并提出完善内地贿赂犯罪的刑事立法建议,以使反腐工作更深入地开展。  相似文献   
396.
2017年8月8日中国四川省九寨沟县Ms 7.0级地震前, 在震源200 km范围内的九寨沟、松潘、平武、青川、茂县和汶川布设AETA系统的6个监测台。采用窗口为30日的滑动主成分分析(principal component analysis, PCA)方法, 对6个台站的电磁扰动进行特征分析, 探讨九寨沟Ms 7.0级地震前后AETA系统观测的电磁场变化特征, 并由此提出一种新的临震特征, 即AETA电磁数据经滑动PCA方法处理后得到的“条带异常”。结果显示: 1) 除九寨沟Ms 7.0级地震发震当日, 九寨沟监测台于震前5日至震后15日, 每天在同一时段(5:00 am—6:00 am)出现异常点, 形成“异常条带”, 异常程度在震前大体上呈递增变化, 震后大体上呈递减变化; 2) 震源附近其他监测台也存在异常点, 但发布零散且异常程度较小; 3) 九寨沟Ms 7.0级地震“异常条带”消失后的两个月内, 未出现新的“异常条带”, 且无强震发生。  相似文献   
397.
借助星的一般点可区别全染色, 讨论2K2∨K1冠图的一般点可区别全染色. 在星的一般点可区别全染色下, 采用将星悬挂边的颜色由小到大依次排列, 最终扩展为2K2∨K1冠图的一般点可区别全染色的方法, 确定冠图依赖于悬挂边数目的一般点可区别全色数.  相似文献   
398.
The photodegradation of bisphenol A (BPA) in aqueous solution containing metal ions and ascorbic acid (AsA) was investigated. After strong irradiation, the aqueous solution containing AsA and Cu2+ could produce hydroxyl radicals that induced the photodegradation of BPA. The photodegradation efficiency of BPA in the solution containing 70 μmol·L−1 Cu2+ and 15 mg·L−1 AsA reached 59% at pH 6.0 after 4 hours irradiation with high pressure mercury lamp. The photodegradation efficiency of BPA reached 10% after 4 hours irradiation with daylight lamp in the presence of 70 μmol·L−1 Cu2+ and 15 mg·L−1 ascorbic acid. BPA was not degraded in the aqueous solution only containing AsA or Cu2+. The BPA photodegradation in aqueous solution containing AsA and Fe3+ was weaker than in aqueous solution that containing AsA and Cu2+ at the same concentration. This work showed a new route of the BPA photodegradation in aqueous environment. Biography: PENG Zhang’e (1970–), female, Ph. D. candidate, research direction: aquatic environmental chemistry.  相似文献   
399.
Traditional procedures for clustering time series are based mostly on crisp hierarchical or partitioning methods. Given that the dynamics of a time series may change over time, a time series might display patterns that may enable it to belong to one cluster over one period while over another period, its pattern may be more consistent with those in another cluster. The traditional clustering procedures are unable to identify the changing patterns over time. However, clustering based on fuzzy logic will be able to detect the switching patterns from one time period to another thus enabling some time series to simultaneously belong to more than one cluster. In particular, this paper proposes a fuzzy approach to the clustering of time series based on their variances through wavelet decomposition. We will show that this approach will distinguish between time series with different patterns in variability as well identifying time series with switching patterns in variability.  相似文献   
400.
An internal structural study was conducted to investigate U-Pb age, trace elements and Hf isotopes of basaltic zircons from the Batamayineishan Formation. The basalt was obtained from drill well San-Can 1 on the eastern Luliang uplift within the Junggar Basin. Trace element data of zircons show that all samples are magmatic, with similar REE patterns, including positive Ce (δCe=5.06–134), but negative Eu (δEu=0.06⦒0.55) anomalies and enrichment in heavy rare earth elements. Among 25 grains, the concordant ages were subdivided into three groups; ages of 300.4±1.3 Ma (n=11), 339.2±2.7 Ma (n=3) and 392.0±1.7 Ma (n=8). Three remaining grains were nearly concordant, with 206Pb/238U ages of 510±7, 488±6 and 453±6 Ma, respectively. The youngest concordant age (i.e., 300.4±1.3 Ma) could be interpreted as the formation age of the studied basaltic rock; this is consistent with the sampling position at the upper part of the Batamayineishan Formation. On the other hand, ages such as Ordovician and early Devonian are consistent with the ages of island-arc volcanic rocks (enrichment in Pb) or ophiolites around the basin. Moreover, the positive ɛ Hf(t) values of the early and middle Paleozoic zircons (+3.6–+10.5) may suggest that the basement traversed by the studied volcanic rocks may be Paleozoic in age, formed from the residual oceanic crust and island-arc complex. The ɛ Hf(t) values (+4.2–+17.1) of the late Paleozoic (∼300.4 Ma) zircons suggest that the basaltic magmas were derived from partial melting of the asthenospheric mantle or depleted lithospheric mantle. These magmas were slightly contaminated by the existence of early-middle Paleozoic materials. The late Carboniferous basalts represent direct eruption of mantle-derived magmas at the upper crustal level during a post-collisional tectonic setting. We therefore consider that extensive vertical growth of the continental crust to have occurred before the late Carboniferous.  相似文献   
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