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Turning a hot spot into a cold spot:polarization-controlled Fano-shaped local-field responses probed by a quantum dot

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Light(Science & Applications) 2020年第1期9卷 417-428页

作者： Juan Xia Jianwei Tang Fanglin Bao Yongcheng Sun Maodong Fang Guanjun Cao Julian evans Sailing He Centre for Optical and Electromagnetic Research State Key Laboratory of Modern Optical InstrumentationNational Engineering Research Center for Optical InstrumentationJORCEPCollege of Optical Science and EngineeringZhejiang University310058 HangzhouChina School of Physics Huazhong University of Science and Technology430074 WuhanChina Centre for Optical and Electromagnetic Research ZJU-SCNU Joint Center of PhotonicsSouth China Academy of Advanced OptoelectronicsSouth China Normal University510006 GuangzhouChina Department of Electromagnetic Engineering School of Electrical EngineeringRoyal Institute of TechnologyS-10044 StockholmSweden

Optical nanoantennas can convert propagating light to local *** local-field responses can be engineered to exhibit nontrivial features in spatial,spectral and temporal domains,where local-field interferences play a key ***,we design nearly fully controllable local-field interferences in the nanogap of a nanoantenna,and experimentally demonstrate that in the nanogap,the spectral dispersion of the local-field response can exhibit tuneable Fano lineshapes with nearly vanishing Fano dips.A single quantum dot is precisely positioned in the nanogap to probe the spectral dispersions of the local-field *** controlling the excitation polarization,the asymmetry parameter q of the probed Fano lineshapes can be tuned from negative to positive values,and correspondingly,the Fano dips can be tuned across a broad spectral ***,at the Fano dips,the local-field intensity is strongly suppressed by up to ~50-fold,implying that the hot spot in the nanogap can be turned into a cold *** results may inspire diverse designs of local-field responses with novel spatial distributions,spectral dispersions and temporal dynamics,and expand the available toolbox for nanoscopy,spectroscopy,nano-optical quantum control and nanolithography.

关键词： quantum local dispersion

Advancing beyond May 1971: How Do We Deal with the Possibility of Complicated Dyke Geometries, Long-Lived Lips, and Contrasting Basement Geological Provinces?

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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 31-33页

作者： David A.D.evans Dep't.of Geology & Geophysics Yale University

The iconic image of a giant radiating dyke swarm subsequently fragmented into three pieces via supercontinental breakup was produced by Paul May in1971(see next page).That figure presented a large part of

关键词： and Contrasting Basement Geological Provinces Long-Lived Lips Advancing beyond May 1971 How Do We Deal with the Possibility of Complicated Dyke Geometries

Animal models of amyotrophic lateral sclerosis： a comparison of model validity

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Neural Regeneration Research 2018年第12期13卷 2050-2054页

作者： Jessica R.Morrice Cheryl Y.Gregory-evans Christopher A.Shaw Experimental Medicine Program University of British Columbia Vancouver Canada Department of Ophthalmology and Visual Sciences University of British Columbia Vancouver Canada Neuroscience Program University of British Columbia Vancouver Canada Department of Pathology. University of British Columbia Vancouver Canada

Animal models are necessary to investigate the pathogenic features underlying motor neuron degeneration and for therapeutic development in amyotrophic lateral sclerosis（ALS）. Measures of model validity allow for a critical interpretation of results from each model and caution from over-interpretation of experimental models. Face and construct validity refer to the similarity in phenotype and the proposed causal factor to the human disease, respectively. More recently developed models are restricted by limited phenotype characterization, yet new models hold promise for novel disease insights, thus highlighting their importance. In this article, we evaluate the features of face and construct validity of our new zebrafish model of environmentally-induced motor neuron degeneration and discuss this in the context of current environmental and genetic ALS models, including C9 orf72, mutant Cu/Zn superoxide dismutase 1 and TAR DNA-binding protein 43 mouse and zebrafish models. In this mini-review, we discuss the pros and cons to validity criteria in each model. Our zebrafish model of environmentally-induced motor neuron degeneration displays convincing features of face validity with many hallmarks of ALS-like features, and weakness in construct validity. However, the value of this model may lie in its potential to be more representative of the pathogenic features underlying sporadic ALS cases, where environmental factors may be more likely to be involved in disease etiology than single dominant gene mutations. It may be necessary to compare findings between different strains and species modeling specific genes or environmental factors to confirm findings from ALS animal models and tease out arbitrary strain-and overexpression-specific effects.

关键词： amyotrophic lateral sclerosis motor neuron degeneration face validity construct validity zebrafish models mouse models genetic models environmental models

Synthesis of a-SnWO_4 thin-film electrodes by hydrothermal conversion from crystalline WO_3

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Chinese Chemical Letters 2015年第4期26卷 474-478页

作者： Kayla J.Pyper Taylor C.evans Bart M.Bartlett Department of Chemistry University of Michigan

Thin film electrodes of the orthorhombic form of tin tungstate （α-SnWO4） were prepared using a hydrothermal method to convert thin films of WO3 in aqueous SnCI2. The pH dependence of the growth mechanism was identified by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The XRD patterns show complete conversion of WO3（s） to SnWO4（s） at pH 1, 4, and 7. SEM images reveal a morphology change from sponge-like platelets to sharp nanowires as the pH increases from 1 to 7. The α-SnWO4 thin films were reddish brown in color, and display an indirect band gap of 1.9 eV by diffuse reflectance UV-vis spectroscopy. α-SnWO4 is therefore solar-responsive, and a chopped light linear sweep voltammogram recorded under 100 mW/cm2 AM1.5 simulated solar illumination in a pH 5 0.1 mol/L KPi buffer show a visible light response for photoelectrochemical water oxidation, producing 32 μA/cm2 at 1.23 V vs. RHE.

关键词： Alpha tin tungstateHydrothermal conversionMicrostructureHydrothermal method

The evolution of lower extremity reconstruction

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Plastic and Aesthetic Research 2022年第1期9卷 182-195页

作者： Brogan G.A.evans David L.Colen Division of Plastic and Reconstructive Surgery Department of SurgeryYale School of MedicineNew HavenCT 06510USA

Reconstruction of the lower extremity is a complex task that has evolved greatly in both technique and indication over the past *** advances in treating traumatic lower extremity injuries focused on primary amputation to avoid the high mortality of *** introduction of antibiotics improved surgical debridement and local reconstructive options,enhancing the viability of lower extremities with simple and proximal *** the advent of microvascular surgery,free tissue transfer techniques provided a means to reconstruct more distal and complex *** these surgical techniques have continued to evolve,so too have indications for reconstruction,patient management and post-operative care-now with a greater emphasis on patient quality of life and limb *** purpose of this article is to outline the evolution of lower extremity reconstruction,and how the standard of practice has changed over time.

关键词： Lower extremity lower extremity reconstruction limb salvage free flap perforator flap vascularized bone flap orthoplastic surgery

Taxonomic revision of lizards from the Paleocene deposits of the Qianshan Basin, Anhui, China

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古脊椎动物学报 2016年第3期54卷 243-268页

作者： DONG Li-Ping Susan E. evans WANG Yuan Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology Chinese Aeademy ofScienees Beijing 100044 China Department of Cell and Developmental Biology University College Lonclon London WC1E6BT.UK)

Although the Late Cretaceous lizard fauna of China and Mongolia is relatively well-known, information on Paleocene lizards from the same region is currently limited. Several species of lizards have been reported from the Paleocene Wanghudun and Doumu formations of Qianshan Basin on the basis of fragmentary specimens, namely Agama sinensis Hou, 1974, Anhuisaurus huainanensis Hou, 1974, Anqingosanrus brevicephalus Hou, 1976, Changjiangosaurus huananensis Hou, 1976, Qianshanosaurus huangpuensis Hou, 1974, and Tinosaurus doumuensis Hou, 1974. In this paper, we review all the reported material of these taxa with the aid of new technology, including CT scanning, and according to current views of squamate relationships and classification. Revised descriptions and classifications are given for each taxon, leading to changes in our understanding of faunal composition. This, in turn, reveals greater morphological and ecological diversity among the Paleocene lizards of the Qianshan Basin, including the occurrence of a varaniform (IVPP V 22767), and the reinterpretation of Anqingosaurus as a possible burrower. Further work on the Paleocene Qianshan lizards is ongoing and the discovery of new specimens may help to solve the puzzles these strange lizards have posed.

关键词： Qianshan Basin Anhui Paleocene lizards phylogeny taxonomic revision CT-scan

Effect of baffles on performance of fluid catalytic cracking riser

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Particuology 2018年第3期16卷 18-30页

作者： Milinkumar T. Shah Vishnu K. Pareek Geoffrey M. evans Ranjeet P. Utikar Department of Chemical Engineering Curtin University Western Australia Australia Department of Chemical Engineering University of Newcastle New South Wales Australia

Increasing demand of automobile fuel and a need to process heavier crude oil makes it imperative to find improvements to the design of existing fluid catalytic cracking （FCC） units. Several modifications to the design of the riser section of FCC units have been suggested in previous studies including： improved feed nozzle designs, multiple nozzle configurations, internal baffles, and novel two-stage-riser systems. In this study, we investigate the effects of baffles on the performance of FCC risers using computational fluid dynamics simulations. In this study, predictions from a basis model （without baffles） are compared with those from four different configurations including：（i） 5-cm baffles at 5-m spacing, （ii） 7.5-cm baffles at 5- m spacing, （iii） 10-cm baffles with 5-m spacing, （iv） lO-cm baffles at 2.5-m spacing, and （v） lO-cm baffles at 1-m spacing. The baffles force the catalyst away from wails toward the center of the riser, enhancing the radial dispersion of the catalyst and the heat transfer inside the riser. The use of longer baffles and smaller spacings further increases the dispersion, yielding more homogeneous radial profiles. The changes in the radial dispersion result in variations in the conversion, yields, and pressure drops. The baffles increase conversion of vacuum gas oil （VGO） and the yield of gasoline. However, the simulations showed that longer baffles and a larger number of baffles did not always give a higher yield or higher conversion. Among the simulated configurations, the 5-cm baffles at 5-m spacing gave the highest conversion of VGO, whereas the 10-cm baffles at 1 -m spacing resulted in the highest yield of the gasoline. Thus, rational optimization of baffle configurations is required to achieve optimal performance.

关键词： Fluid catalytic cracking Riser Baffles Computational fluid dynamics

Theoretical Analysis of the Fluctuation Theorem Applied to Electric Circuits

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Communications in Theoretical Physics 2014年第10期61卷 476-484页

作者： Charlotte F.Petersen Elmars Krausz Denis J.evans Stephen R.Williams Research School of Chemistry Australian National UniversityCanberraACT 0200Australia

We carry out a theoretical analysis of the fluctuations in the Johnson–Nyquist noise in an RC electric circuit being driven by a non-ideal constant current source. Using the appropriate Langevin equation, we derive the fluctuation theorem for the system. This analysis exhibits some interesting features. Firstly, the average of the dissipation function is not necessarily just an instantaneous entropy production, i.e. the work being done on the circuit by the external power source divided by the ambient temperature. Secondly, by appropriate selection of the values for the circuit components,the transient response of the system can be made identical to the nonequilibrium steady state response. In the limit of an ideal current source, the average of the dissipation function reduces to the entropy production. Our analysis accurately reproduces published experimental results.

关键词： circuit analysis fluctuation theorems statistical machanics Johnson noise