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91.
This study has been undertaken to provide an insight into the effects of mineral matter distributions in coal on the nature of boiler slags formed during the combustion of a high ash Spanish anthracite. Three density fractions were prepared, and the light and heavy fractions were combined to give a sample containing mainly excluded mineral matter. The mineral matter in the medium density fraction was predominantly included. Slag deposits were prepared in the laboratory from the whole coal, the light+heavy and medium density fractions. The coal with excluded mineral matter was found to produce a slag similar in nature and chemistry to the whole coal ash deposit. The coal with included mineral matter produced a vitreous, iron-rich deposit. The deposits were compared with slags, obtained from a Spanish power station boiler, burning a blend containing the same anthracite.  相似文献   
92.
Wang H  Ou LM  Suo Y  Yu HZ 《Analytical chemistry》2011,83(5):1557-1563
A method for the convenient detection of lead at the parts-per-billion (ppb)-level has been developed; it uses a conventional compact disc (CD) as the platform for preparing DNAzyme assays and an unmodified optical drive of ordinary desktop/laptop computers as the readout device. In particular, by immobilization of Pb(2+)-specific DNAzyme sensing constructs on the "transparent side" of a conventional CD-R via mild surface reactions, the Pb(2+) concentration can be determined by a free diagnostic program that checks the error distribution on the CD (i.e., it extracts the number of errors in a prerecorded audio file). The reading errors increase monotonically over a wide range of Pb(2+) concentrations (from 10 nM to 1 mM), and the selectivity is confirmed by testing several other divalent cations (Zn(2+), Ba(2+), Mg(2+), Ca(2+), Cu(2+), and Hg(2+)).  相似文献   
93.
Phosphorescent organic light emitting diodes (PHOLEDs) have undergone tremendous growth over the past two decades. Indeed, they are already prevalent in the form of mobile displays, and are expected to be used in large‐area flat panels recently. To become a viable technology for next generation solid‐state light source however, PHOLEDs face the challenge of achieving concurrently a high color rendering index (CRI) and a high efficiency at high luminance. To improve the CRI of a standard three color white PHOLED, one can use a greenish‐yellow emitter to replace the green emitter such that the gap in emission wavelength between standard green and red emitters is eliminated. However, there are relatively few studies on greenish‐yellow emitters for PHOLEDs, and as a result, the performance of greenish‐yellow PHOLEDs is significantly inferior to those emitting in the three primary colors, which are driven strongly by the display industry. Herein, a newly synthesized greenish‐yellow emitter is synthesized and a novel device concept is introduced featuring interzone exciton transfer to considerably enhance the device efficiency. In particular, high external quantum efficiencies (current efficiencies) of 21.5% (77.4 cd/A) and 20.2% (72.8 cd/A) at a luminance of 1000 cd/m2 and 5000 cd/m2, respectively, have been achieved. These efficiencies are the highest reported to date for greenish‐yellow emitting PHOLEDs. A model for this unique design is also proposed. This design could potentially be applied to enhance the efficiency of even longer wavelength yellow and red emitters, thereby paving the way for a new avenue of tandem white PHOLEDs for solid‐state lighting.  相似文献   
94.
In this study, in vivo animal experiments with 12 nude mice bearing breast-cancer-patient-tissue-derived xenograft (PDX) tumors were performed aiming to verify the imaging capability of a novel miniaturized fluorescence molecular tomography (FMT) endoscope, in combination with targeted nanoparticle–near-infrared (NIR) dye conjugates. Tumor-bearing mice were divided into two groups by systematic injection with urokinase plasminogen activator receptor-targeted (n = 7) and nontargeted (n = 5) imaging nanoprobes as a contrast agent, respectively. Each mouse was imaged at 6, 24, and 48 h following the injection of nanoprobes using the FMT endoscope. The results show that systemic delivery of targeted nanoprobes produced a 4-fold enhancement in fluorescence signals from tumors, compared with tumors that received nontargeted nanoprobes. This study indicates that our miniaturized FMT endoscope, coupled with the targeted nanoparticle–NIR dye conjugates as a contrast agent, has high sensitivity and specificity, and thus great potential to be used for image-guided detection and removal of a primary tumor and local metastatic tumors during surgery.  相似文献   
95.
96.
This article explores enabling conditions of creativity and transformative agency in the field of community development. Based on a comparative case study of the Los Angeles Green Retrofit and Workforce Program and Evergreen Cooperative Initiative in Cleveland, it finds a combination of problematic situations at the field and organizational level, individual biographical factors and available resources, and the presence of trusted intermediaries enabled alternative community development practices. In seeking to contribute to institutional planning theory on the paradox of embedded agency, it builds on the pragmatist planning approach to consider such multi-level enabling conditions and interim activities of individuals and organizations working towards institutional change. At the same time, it addresses shortcomings of pragmatist planning by attending to the role of particular historical actors, institutions, and policies in “problem solving” within the specific case studies along with the implications of structural disadvantage and inequality and sociocultural diversity for governance processes.  相似文献   
97.
98.
Approaches to safely and effectively augment cellular functions without compromising the inherent biological properties of the cells, especially through the integration of biologically labile domains, remain of great interest. Here, a versatile strategy to assemble biologically active nanocomplexes, including proteins, DNA, mRNA, and even viral carriers, on cellular surfaces to generate a cell-based hybrid system referred to as “Cellnex” is established. This strategy can be used to engineer a wide range of cell types used in adoptive cell transfers, including erythrocytes, macrophages, NK cells, T cells, etc. Erythrocytenex can enhance the delivery of cargo proteins to the lungs in vivo by 11-fold as compared to the free cargo counterpart. Biomimetic microfluidic experiments and modeling provided detailed insights into the targeting mechanism. In addition, Macrophagenex is capable of enhancing the therapeutic efficiency of anti-PD-L1 checkpoint inhibitors in vivo. This simple and adaptable approach may offer a platform for the rapid generation of complex cellular systems.  相似文献   
99.
<正> China's exports and trade in July all hit arecord high since July 2008.Exports thisJuly surged by 38.1% year-on-year toUS$145.52 billion and imports increased22.7% year-on-year to US$116.79 billion,the General Administration of Customs ofChina released on August 10th.The monthly trade surplus in Julyreached US$28.73 billion compared withUS$20.03 billion in June, close to the largestChina has ever seen.On a monthly basis, China's exports inJuly were up 5.9% from June, but importsshrank 0.4% from the previous month, in-  相似文献   
100.
为研究高电压体系锂离子电池浮充性能的影响因素,对浮充失效电池的产气成分、正负极材料的结构变化、金属溶出情况、隔膜形貌及Gurley值变化等进行了深入分析研究,结果表明:电池在长时间高温浮充过程中,正极材料发生相变,金属元素溶出,同时释放O2造成电解液的氧化分解;高温高电压状态下负极SEI膜也会破坏,并发生不断的重整及修复反应,这些反应产物沉积到负极表面及隔膜孔隙内,导致靠近负极侧的隔膜孔隙堵塞甚至贯穿,即引起正负极微短路,释放出大量气体。通过提高正极材料的结构稳定性、优化电解液形成稳定的CEI和SEI,改善增加隔膜的穿刺强度都能明显改善电池的高温浮充性能。  相似文献   
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