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Propulsion and Power Research 2014年第1期3卷 9-14页

作者： Navid Mehrjoo Rocco Portaro Hoi dick Ng Department of Mechanical and Industrial Engineering Concordia UniversityMontréalQCH3G 1M8Canada

A simple method of detonation transmission from a small tube to a large area is *** technique involves placing obstacles which create slight blockages at the exit of the confined tube before the planar detonation emerges into the larger space,thereby generating flow instability to promote the detonation *** this experimental study two mixtures of undiluted stoichiometric acetylene-oxygen and acetylene-nitrous oxide are *** mixtures can be characterized by a cellular detonation front that is irregular and representative of those potentially used in practical aerospace *** blockage ratio imposed by the obstacles is varied systematically to identify the optimal condition under which a significant reduction in critical pressure for transmission can be obtained.A new perturbation configuration for practical use in propulsion and power systems is also introduced and results are in good agreement with those obtained using thin needles as the blockage ratio is kept constant.

关键词： Combustion Detonation Pulse detonation engines Diffraction Perturbation Reactive flow

Mineralogical characteristics and photocatalytic properties of natural sphalerite from China

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Journal of Environmental Sciences 2020年第3期32卷 156-166页

作者： Can Shen Xiangping Gu Bin Yang Dexian Zhang Zhilin Wang Zhengxiang Shu Jeffrey dick Anhuai Lu Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of Education Central South UniversityChangsha 410083China School of Geoscience and Info-physics Central South UniversityChangsha 410083China

Different natural sphalerites have a range of photocatalytic properties that can potentially be exploited for environmental remediation *** develop value in the exploitation of sphalerite,samples were collected from 19 ore deposits in China and characterized for their mineralogical and photocatalytic properties.X-ray diffraction(XRD) and electron probe micro analysis(EPMA) measurements indicated that all the natural sphalerites from various localities crystallized in cubic phases with various chemical *** substitution of Fe for Zn ranged from 0.235% to 14.826% by weight,Mn from 0.004% to4.868%,Cu from 0.009% to 5.529% and Cd from 0.133% to 1.576%.As Fe became more abundant,the color of natural sphalerite darkened,becoming almost black;and higher Fe content was associated with stronger visible light *** spectra showed emission mainly related to S-vacancies and progressively decreasing fluorescence intensity with increasing Fe *** of the photocatalytic degradation of methyl orange indicated that the sample with the highest Cd content but moderate Fe content had the highest photocatalytic ***,the degradation of Methyl Orange(30 mg/L)attained 82.11% efficiency under visible light irradiation for 4 hr of natural sphalerite with4.262% Fe and 1.576% ***,the Fe content in sphalerite was found to contribute to the visible light absorption ability and the recombination rate of photo-generated electrons and holes,while substitution by Cd was observed to have a greater effect on the photocatalytic *** findings provide a scientific basis for the profitable utilization of base metal resources like sphalerite.

关键词： Natural sphalerite Mineralogical properties Band gap Photodegradation of Methyl Orange

Molecular mechanisms of heavy metal tolerance and evolution in invertebrates

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Insect Science 2009年第1期16卷 3-18页

作者： Thierry K. S. Janssens dick Roelofs Nico M. van Straalen Department of Animal Ecology Institute of Ecological Science VU University Amsterdam The Netherlands

Following the genomics revolution, our knowledge of the molecular mechanisms underlying defenses against stress has been greatly expanded. Under strong selective pressure many animals may evolve an enhanced stress tolerance. This can be achieved by altering the structure of proteins （through mutations in the coding regions of genes） or by altering the amount of protein （through changes in transcriptional regulation）. The latter type of evolution can be achieved by substitutions in the promoter of the gene of interest （cisregulatory change） or by altering the structure or amount of transcriptional regulator proteins （trans-regulatory change）. The metallothionein system is one of the best studied stress response systems in the context of heavy metals. Metallothionein expression is assumed to be regulated by metal transcription factor 1 （MTF-1）; however, up to now the involvement of MTF- 1 has only been proven for some vertebrates and Drosophila. Data on invertebrates such as nematodes and earthworms suggest that other mechanisms of metallothionein induction may be present. A detailed study of Cd tolerance was done for a species of soilliving springtail, Orchesella cincta. The metallothionein gene of this species is overexpressed in metal-exposed field populations. Analysis of the metallothionein promoter has demon- strated extensive polymorphisms that have a fimctional significance, as shown in bioreporter assays. In a study comparing 20 different populations, the frequency of a high-expresser promoter allele was positively correlated with the concentration of metals in soil, especially Cd. The springtail study shows that cis-regulatory change of genes involved in the cellular stress response may contribute to evolution of metal tolerance.

关键词： Collembola evolution heavy metals metallothionein metal transcription factor 1 Orchesella cincta tolerance

A Novel Evolutionary Genetic Optimization-Based Adaptive Neuro-Fuzzy Inference System and Geographical Information Systems Predict and Map Soil Organic Carbon Stocks Across an Afromontane Landscape

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Pedosphere 2017年第5期27卷 877-889页

作者： kennedy o.were dieu tien bui Φystein bjarne dick bal ram singh Department of Mathematical Sciences and Technology Norwegian University of Life SciencesP.O.Box 5003 NO.1432 AsNorway Kenya Agricultural and Livestock Research Organisation Kenya Soil SurveyP.O.Box 14733—00806 NairobiKenya Department of Business Administration and Computer Science Faculty of Arts and SciencesUniversity College of Southeast NorwayNO一3800 BΦi TelemarkNoway Department of Environmental Sciences Norwegian University of Life SciencesP.O.Box 5003NO一1432 AsNorway

Soil organic carbon （SOC） pool has the potential to mitigate or enhance climate change by either acting as a sink, or a source of atmospheric carbon dioxide （CO2） and also plays a fundamental role in the health and proper functioning of soils to sustain life on Earth. As such, the objective of this study was to investigate the applicability of a novel evolutionary genetic optimization-based adaptive neuro-fuzzy inference system （ANFIS-EG） in predicting and mapping the spatial patterns of SOC stocks in the Eastern Mau Forest Reserve, Kenya. Field measurements and auxiliary data reflecting the soil-forming factors were used to design an ANFIS-EG model, which was then implemented to predict and map the areal differentiation of SOC stocks in the Eastern Mau Forest Reserve. This was achieved with a reasonable level of uncertainty （i.e., root mean square error of 15.07 Mg C ha-l）, hence demonstrating the applicability of the ANFIS-EG in SOC mapping studies. There is potential for improving the model performance, as indicated by the current ratio of performance to deviation （1.6）. The mapping also revealed marginally higher SOC stocks in the forested ecosystems （i.e., an average of 109.78 M C ha-1） than in the aro-ecosvstems （i.e., an average of 95.9 Mg C ha-l）.

关键词： artificial neural networks carbon sequestration climate change mitigation digital elevation model digital soil mapping,Eastern Mau Forest Reserve fuzzy logic

MEASUREMENT OF THE EFFICIENCY OF EVACUATED TUBE SOLAR COLLECTORS UNDER VARIOUS OPERATING CONDITIONS

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Journal of Green Building 2012年第3期7卷 114-130页

作者： S.E.Zubriski K.J.dick Department of Biosystems Engineering University of ManitobaWinnipegCanada

The operating efficiency of evacuated tubes themselves under varying environmental conditions and installation scenarios,independent of water and space heating auxiliary equipment,are not readily available ***,Manitoba specific data has not been *** purpose of this research program was to measure the efficiency of evacuated tube solar collectors under various operating conditions including:the angle of inclination towards the incident solar radiation,heat transfer fluid flow rate,glazing installation,and number of evacuated *** operating conditions and configurations were chosen to represent realistic or probable installation scenarios and environmental ***,the research aimed to identify the suitability of evacuated tube solar collectors to each of the *** design values are of use for appropriate sizing of water or space heating systems,system configuration and optimization,and calculation of return on *** scope of the research project was limited to the efficiency of various configurations of a 32-tube panel,not the entire solar domestic hot water or space heating ***,factors such as heat loss in the tubing,solar storage tank,and heat exchanger efficiency were not *** findings indicated that efficiency varied by approximately 5%between the different collector configurations,as observed from the overlay graph of *** the efficiency of a collector is considered within a system it is proposed that effectiveness may be a better measure of overall performance.

关键词： solar collector evacuated tube solar hot water

Circulating inflammatory factors associated with worse long-term prognosis in colorectal cancer

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World Journal of Gastroenterology 2017年第34期23卷 6212-6219页

作者： Renate S Olsen Johnny Nijm Roland E Andersson Jan Dimberg dick Wagsater Division of Medical Diagnostics Department of Laboratory MedicineRegion Jonkoping County Division of Drug Research Department of Medicine and Health SciencesFaculty of Medicine and Health SciencesLinkoping University Division of Medical Diagnostics Department of Clinical PhysiologyRegion Jonkoping County Department of Surgery Region Jonkoping County Department of Clinical and Experimental Medicine Faculty of Medicine and Health SciencesLinkoping University Department of Natural Science and Biomedicine School of Health and WelfareJonkoping University

AIM To investigate association of circulating inflammatory factors at the time of colorectal cancer(CRC) surgery with *** Plasma levels from 174 CRC patients(69 females and 105 men), with median age 70 years(range 29-90), localized in the colon(n = 105) or rectum(n = 69), with stage Ⅰ(n = 24), stage Ⅱ(n = 54), stage Ⅲ(n = 67) and stage Ⅳ(n = 29) were measured using commercially available Bio-Plex Pro? Human Chemokine Panel 40-Plex, including 40 different chemokines, cytokines and interleukins. The prognostic association of each inflammatory factor was analysed as CRC-specific and total *** Out of 174 patients, 66 died during the follow-up, 40 because of CRC specific mortality. High tertile levels of 8 factors were significantly associated with increased CRC-specific mortality, of which CCL1, CCL20, CCL24, CX3CL1, IL-4 and TNF-α remained significant in a multivariate Cox regression analysis. High tertile levels of 14 factors were associated with increased total mortality, of which CCL1, CCL15, CCL20, CX3CL1, CXCL13, IFN-γ, IL-2, IL-4 and IL-10 remained significant after adjustment for clinical covariates. For most of the inflammatory factors the association between higher tertile levels and an increased mortality in general appeared two years after surgery. High tertile levels of TNF-α and CCL24 were exclusively associated with CRC-specific mortality. The distribution of these factors were not associated with TNM stage with exception for *** High plasma levels of inflammatory factors are associated with increased risk of mortality among CRC patients and could be potential biomarkers for revealing prognosis.

关键词： Colorectal cancer Inflammation Cytokines Plasma Prognosis Mortality

High resolution scanning gate microscopy measurements on InAs/GaSb nanowire Esaki diode devices

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Nano Research 2014年第6期7卷 877-887页

作者： James L. Webb Olof Perssor Kimberly A. dick Claes Thelander Rainer Timm Anders Mikkelsen Division of Synchrotron Radiation Research Lund University Sweden Center forAnalysis and Synthesis Lund University Sweden Division of Solid State Physics Lund University Sweden

Gated transport measurements are the backbone of electrical characterization of nanoscale electronic devices. Scanning gate microscopy （SGM） is one such gating technique that adds crucial spatial information, accessing the localized properties of semiconductor devices. Nanowires represent a central device concept due to the potential to combine very different materials. However, SGM on semiconductor nanowires has been limited to a resolution in the 50-100 nm range. Here, we present a study by SGM of newly developed III-V semiconductor nanowire InAs/GaSb heterojunction Esaki tunnel diode devices under ultra-high vacuum. Sub-5 nm resolution is demonstrated at room temperature via use of quartz resonator atomic force microscopy sensors, with the capability to resolve InAs nanowire facets, the InAs/GaSb tunnel diode transition and nanoscale defects on the device. We demonstrate that such measurements can rapidly give important insight into the device properties via use of a simplified physical model, without the requirement for extensive calculation of the electrostatics of the system. Interestingly, by precise spatial correlation of the device electrical transport properties and surface structure we show the position and existence of a very abrupt （〈10 nm） electrical transition across the InAs/GaSb junction despite the change in material composition occurring only over 30-50 nm. The direct and simultaneous link between nanostructure composition and electrical properties helps set important limits for the precision in structural control needed to achieve desired device performance.

关键词： nanowire,scanning gate microscopy Esaki tunnel diode,InAs,GaSb,III-V,heterostructure

Estimating traffic volume on Wyoming low volume roads using linear and logistic regression methods

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Journal of Traffic and Transportation Engineering(English Edition) 2016年第6期3卷 493-506页

作者： dick Apronti Khaled Ksaibati Kenneth Oerow Jaime Jo Hepner Department of Civil and Architectural Engineering University of WyomingLaramieWY 82071USA Department of Statistics University of WyomingLaramieWY 82071USA

Traffic volume is an important parameter in most transportation planning applications. Low volume roads make up about 69% of road miles in the United States. Estimating traffic on the low volume roads is a cost-effective alternative to taking traffic counts. This is because traditional traffic counts are expensive and impractical for low priority roads. The purpose of this paper is to present the development of two alternative means of cost- effectively estimating traffic volumes for low volume roads in Wyoming and to make recommendations for their implementation. The study methodology involves reviewing existing studies, identifying data sources, and carrying out the model development. The utility of the models developed were then verified by comparing actual traffic volumes to those predicted by the model. The study resulted in two regression models that are inexpensive and easy to implement. The first regression model was a linear regression model that utilized pavement type, access to highways, predominant land use types, and population to estimate traffic volume. In verifying the model, an R^2 value of 0.64 and a root mean square error of 73.4% were obtained. The second model was a logistic regression model that identified the level of traffic on roads using five thresholds or levels. The logistic regression model was verified by estimating traffic volume thresholds and determining the percentage of roads that were accurately classified as belonging to the given thresholds. For the five thresholds, the percentage of roads classified correctly ranged from 79% to 88%. In conclusion, the verification of the models indicated both model types to be useful for accurate and cost-effective estimation of traffic volumes for low volume Wyoming roads. The models developed were recommended for use in traffic volume estimations for low volume roads in pavement management and environmental impact assessment studies.

关键词： Traffic volume estimation Low volume road Wyoming county roads Transportation planning Regression analysis

Progress in Human Brain Banking in China

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Neuroscience Bulletin 2019年第2期35卷 179-182页

作者： Chao Ma Ai-Min Bao Xiao-Xin Yan dick F. Swaab Institute of Basic Medical Sciences Chinese Academy of Medical Sciences Department of Human Anatomy Histol-ogy and Embryology Neuroscience Center Joint Laboratory of Anesthesia and Pain School of Basic Medicine Peking Union Medical College Department of Neurobiology and Department of Neurology of the Second Affiliated Hospital Institute of Neuroscience NHC and CAMS Key Laboratory of Medical NeurobiologyZhejiang University School of Medicine Department of Anatomy and Neurobiology Central South University School of Basic Medical Science Department Neuropsychiatric Disorders Netherlands Insti-tute for Neuroscience an Institute of the Royal Netherlands Academy of Arts and Sciences

Human brain banks collect,preserve,and distribute postmortem and biopsied brain samples for histological,pathological,and molecular *** from the western countries,human brain banking in China has remained preliminary over ***,joint efforts during the past few years have substantially promoted this key frontier of neuroscience in *** special topic brings together review and perspective articles on the ethical,administrative,and practical issues of brain *** original studies report molecular and pathological characterizations based on banked human brain samples.

关键词： collect Progress Banking

Advanced Java networking /++dick Steflik, Prashant Sridharan. 2nd ed.

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