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1.
The application of UV irradiation processes are successfully proposed for the first time in the fabrication of both of the two plastic electrodes in flexible dye solar cells (DSCs) and modules. For the realization of the photo‐electrode, a customized TiO2 paste formulation and UV processing method was developed which yields 134% (48%) performance enhancement with respect to the same (binder‐free) paste treated at 120 °C. UV treatment induces both complete removal of organic media and more efficient charge collection. Significantly, highly catalytic platinized flexible counter‐electrodes are also obtained via UV photo‐induced reduction of screen‐printed platinum precursor pastes based on hexachloroplatinic acid. Using both UV‐processed electrodes, a fully plastic DSC is fabricated with a conversion efficiency of 4.3% under 1 Sun (semitransparent) and 5.3% under 0.2 Sun (opaque). Performance is within 10% of the efficiency of a glass‐based DSC prepared with the same materials but with conventional high temperature processes. The material formulations and processes are simple, and easily up‐scaled over large areas, even directly and simultaneously applicable to the preparation of both the photo‐and counter‐electrode on the same substrate which enabled us to demonstrate the first module on plastic realized with a W series interconnection.  相似文献   
2.
Jiráková K  Kulda J  Nohýnková E 《Protist》2012,163(3):465-479
Differentiation into infectious cysts (encystation) and multiplication of pathogenic trophozoites after hatching from the cyst (excystation) are fundamental processes in the life cycle of the human intestinal parasite Giardia intestinalis. During encystation, a bi-nucleated trophozoite transforms to a dormant tetra-nucleated cyst enveloped by a protective cyst wall. Nuclear division during encystation is not followed by cytokinesis. In contrast to the well-studied mechanism of cyst wall formation, information on nuclei behavior is incomplete and basic cytological data are lacking. Here we present evidence that (1) the nuclei divide by semi-open mitosis during early encystment; (2) the daughter nuclei coming from different parent nuclei are always arranged in pairs; (3) in both pairs, the nuclei are interconnected via bridges formed by fusion of their nuclear envelopes; (4) each interconnected nuclear pair is associated with one basal body tetrad of the undivided diplomonad mastigont; and (5) the interconnection between nuclei persists through the cyst stage being a characteristic feature of encysted Giardia. Based on the presented results, a model of nuclei behavior during Giardia differentiation is proposed.  相似文献   
3.
森林-草原交错带土壤节肢动物群落多样性   总被引:5,自引:1,他引:4  
在河北北部的塞罕坝森林草原交错区进行了土壤节肢动物群落组成与多样性调查,共获得土壤节肢动物25类,10420头,分属于6纲24目.交错区地带土壤节肢动物群落优势类群为弹尾目和蜱螨目,常见类群有8类,稀有类群15类.群落的多样性分析表明,森林带的多样性指数(H′)、密度-类群指数(DG)和均匀度指数较大,而草甸草原带各种指数较小.pH值与土壤节肢动物的类群数关联度较大,而温度和含水量与土壤节肢动物的个体数关联度较大.  相似文献   
4.
We analyze the parallel time and speedup for processing a divisible load on (1) a linear array with a corner initial processor; (2) a linear array with an interior initial processor; (3) a mesh with a corner initial processor; (4) a mesh with an interior initial processor; (5) a b-ary complete tree with the root as the initial processor; (6) a pyramid with the apex as the initial processor. Due to communication overhead and limited network connectivity, the speedup of parallel processing for a divisible load on static interconnection networks with constant node degrees is bounded from above by a quantity independent of network size. It is shown that for the above six cases, as the network size becomes large, the asymptotic speedup is approximately , 2 , 3/4, 43/4, (b–1), and 3, respectively, where is the ratio of the time for computing a unit load to the time for communicating a unit load. We also investigate divisible load distribution on hypercubes. Our strategy takes advantage of the recursive structure of a hypercube. It is proven that linear speedup can be achieved as the communication cost becomes smaller and smaller.  相似文献   
5.
Interconnection of epithelial tubules is a crucial process during organogenesis. Organisms have evolved sets of molecular and cellular strategies to generate an interconnected tubular network during animal development. Spatiotemporal control of common cellular strategies includes dissolution of the basement membrane, apoptosis, rearrangements of cell adhesion junctions, and mesenchymal-like invasive cellular behaviors prior to tubular interconnection. Different model systems exhibit varying degrees of active invasive-like behaviors that precede tubular interconnection, which may reflect changes in cell polarity or differential adhesive cell states. Studies in this newly-emerging field of tubular interconnections will provide a greater understanding of pediatric diseases and cancer metastasis, as well as generate fundamentally new insights into lumen formation pathology, or lumopathies.  相似文献   
6.
InfiniBand is a new industry-wide general-purpose interconnect standard designed to provide significantly higher levels of reliability, availability, performance, and scalability than alternative server I/O technologies. After more than two years since its official release, many are still trying to understand what are the profitable uses for this new and promising interconnect technology, and how this technology might evolve. In this article, we provide a summary of several industry and academic perspectives on this issue expressed during a panel discussion at the Workshop for Communication Architecture for Clusters (CAC), held in conjunction with the International Parallel and Distributed Processing Symposium (IPDPS) in April 2001, in hopes of narrowing down the design space for InfiniBand-based systems.  相似文献   
7.
三种类型草地植物种间关联的测定与比较   总被引:6,自引:0,他引:6  
植物种间关联的研究,对于进一步确定植物种间关系、揭示群落演替过程中植物种间替代关系的机制、草场退化和人工草地产量下降的原因都有重要意义。本文之所以选取三种类型的草地进行研究主要是考虑到由于一个群落从初期阶段到顶极阶段的演替需要十几年甚至几十年的时间,这样对于演替不同阶段植物种间关联的观测是困难的。故在本文中我们采用  相似文献   
8.
9.
南方红豆杉群落主要树木种群间联结关系初步研究   总被引:27,自引:4,他引:23  
南方红豆杉(Taxuschinensisvar.mairei)是红豆杉科红豆杉属植物、林业部确定的国家一级保护树种,木材材质优良,更因其含高效抗癌药物紫杉醇(taxol)而备受关注。南方红豆杉自然分布于华东、中南、西南以及陕西、甘肃的南部、台湾等地。...  相似文献   
10.
Efficient vacuum‐deposited tandem organic photovoltaic cells (TOPVs) composed of pristine fullerenes as the acceptors and two complementary absorbing donors, 2‐((2‐(5‐(4‐(diphenylamino)phenyl)thieno[3,2‐b]thiophen‐2‐yl)thiazol‐5‐yl)methylene)malononitrile for the visible absorption and 2‐((7‐(5‐(dip‐tolylamino)thiophen‐2‐yl)benzo[c]‐[1,2,5]thiadiazol‐4‐yl)methylene)malononitrile for the near‐infrared absorption, are reported. Two subcells are connected by the interconnection unit (ICU) composed of electron‐transporting layer/metal/p‐doped hole‐transporting layer. The p‐doped layer in the ICU enables increasing the short‐circuit current density (J SC) of TOPVs by tuning the relative position of subcells in the tandem devices to have the maximum optical field distribution response, which is well matched with theoretical calculation. Moreover, the introduction of the doped layer benefits to the higher fill factor (FF) of the consisting subcells without losing open‐circuit voltage (V OC) even with the thick active layers. As a result, power conversion efficiency of 9.2% is achieved with higher FF of 0.62 than that of single‐junction subcells (0.54, 0.57), J SC of 8.7 mA cm?2, and V OC of 1.71 V using 80 nm thick active layers in both subcells.  相似文献   
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