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Extreme ultraviolet radiation for coherent diffractive imaging with high spatial resolution

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Science china(Physics,Mechanics & Astronomy) 2010年第6期53卷 1065-1067页

作者： L.V. DAO S. TEIcHMANN b. cHEN R.A. DILANIAN K.b. DINH P. HANNAFORD centre for Atom Optics and Ultrafast Spectroscopy Swinburne University of Technology Australian Research council centre of Excellence for coherent X-Ray Science School of Physics University of Melbourne

Using different noble gases,argon,neon and helium,we are able to generate by high-harmonic generation(HHG) just a few harmonic orders in the spectral range 10-35 nm with a photon flux of～2.10 12 photons/(harmonic cm2 s) for argon and～10 10 photons/(harmonic cm2 s) for helium. The few-harmonic-order radiation is used for coherent diffractive imaging directly without any spectral filter. A spatial resolution of～100 nm is achieved using a～30 nm HHG source.

关键词： laser applications high harmonic generation coherent diffractive imaging

Systematical approach in evaluation of Lc method for determination of raloxifene hydrochloride and its impurities employing experimental design

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Journal of Pharmaceutical Analysis 2013年第1期3卷 45-52页

作者： b.Jani Stojanovi T.Raki b.Slavkovi N.Kosti A.Vemi A.Malenovi University of belgrade Faculty of PharmacyDepartment of Drug Analysis

Method validation presents a detailed investigation of analytical method and provision of the evidence that the method, when correctly applied, produces results that fit to the purpose. In order to achieve the method validation scope efficiently, experimental design presents a very useful tool. The greatest benefits of such approach could be seen in robustness testing through the provision of very useful data about the control of the chromatograp6hic system during the routine application. In this paper, robustness testing of the Lc method proposed for the determination of raloxifene hydrochloride and its four impurities was done employing Plackett-burman design. Applying this design, the effect of five real factors （acetonitrile content, sodium dodecyl sulfate content, column temperature, pH of the mobile phase and flow rate） on the corresponding resolution factors was investigated through twelve experiments. Furthermore, the insignificance intervals for significant factors were calculated and the parameters for system suitability tests were defined. Eventually, the other validation parameters were tested and the effectiveness of the proposed analytical method with a high degree of accuracy was confirmed.

关键词： Experimental design Method validation Raloxifenehydrochloride Impurities Liquid chromatography

A Deep Learning Modeling Framework to capture Mixing Patterns in Reactive-Transport Systems

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communications in computational Physics 2022年第1期31卷 188-223页

作者： N.V.Jagtap M.K.Mudunuru K.b.Nakshatrala Department of Mechanical Engineering University of HoustonTexas 77204USA Atmospheric Sciences&Global change Division Pacific Northwest National LaboratoryRichlandWashington 99352USA Department of civil&Environmental Engineering University of HoustonHoustonTexas 77204USA

Prediction and control of chemical mixing are vital for many scientific areas such as subsurface reactive transport, climate modeling, combustion, epidemiology, and pharmacology. Due to the complex nature of mixing in heterogeneous andanisotropic media, the mathematical models related to this phenomenon are not analytically tractable. Numerical simulations often provide a viable route to predict chemical mixing accurately. However, contemporary modeling approaches for mixing cannot utilize available spatial-temporal data to improve the accuracy of the future prediction and can be compute-intensive, especially when the spatial domain is large andfor long-term temporal predictions. To address this knowledge gap, we will present inthis paper a deep learning (DL) modeling framework applied to predict the progress ofchemical mixing under fast bimolecular reactions. This framework uses convolutionalneural networks (cNN) for capturing spatial patterns and long short-term memory(LSTM) networks for forecasting temporal variations in mixing. by careful design ofthe framework—placement of non-negative constraint on the weights of the cNN andthe selection of activation function, the framework ensures non-negativity of the chemical species at all spatial points and for all times. Our DL-based framework is fast,accurate, and requires minimal data for training. The time needed to obtain a forecastusing the model is a fraction (≈ O(10−6)) of the time needed to obtain the result using a high-fidelity simulation. To achieve an error of 10% (measured using the infinitynorm) for capturing local-scale mixing features such as interfacial mixing, only 24%to 32% of the sequence data for model training is required. To achieve the same levelof accuracy for capturing global-scale mixing features, the sequence data required formodel training is 64% to 70% of the total spatial-temporal data. Hence, the proposedapproach—a fast and accurate way to forecast long-time spatial-temporal mixin

关键词： Deep learning reactive-transport non-negative solutions spatial-temporal forecasting pattern recognition convolutional neural networks(cNN) long short-term memory(LSTM) networks

Modelling Impact of Dredging and Dumping in Ebb-Flood channel Systems

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Transactions of Tianjin University 2008年第4期14卷 271-281页

作者： HIbMA A WANG Z b STIVE M J F Vriend H J de Delft University of Technology P O Box 5048 2600 GA Delft the Netherlands

For a channel-shoal system in a funnel-shaped basin the impact of dredging and dumping is investigated using a complex process-based model. First, the residual flow and sediment transport circulations are analysed for the channel-shoal pattern, which has emerged after a longterm model simulation. Results are compared to the Western Scheldt estuary, which forms the inspiration for this study. Subsequently, different dredge and dump scenarios are modelled, according to a conceptual model, in which ebb- and flood-channels and enclosed shoals form morphodynamic units (cells) with their own sediment circulation. Model results show that dumping sediment in a channel further reduces the channel depth and induces erosion in the opposite channel, which enhances tilting of the cross-section of the cell and eventually can lead to the degeneration of a multiple channel system into a single channel. The impact of different dredging and dumping cases agrees with results from a stability analysis. This means that this type of model applied to a realistic geometry can potentially be used for better prediction of the impact of human interventions.

关键词： estuaries morphology numerical model channel shoal dredging dumping

Sensitivity of the Indian Monsoon to Human Activities

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Advances in Atmospheric Sciences 2008年第6期25卷 932-945页

作者： b. KNOPF K. ZIcKFELD M. FLEcHSIG V. PETOUKHOV Potsdam Institute for climate Impact Research (PIK) School of Earth and Ocean Sciences University of Victoria

In this paper the authors perform an extensive sensitivity analysis of the Indian summer monsoon rainfall to changes in parameters and boundary conditions which are influenced by human activities. For this study the authors use a box model of the Indian monsoon which reproduces key features of the observed monsoon dynamics such as the annual course of precipitation and the transitions between winter and summer regimes. because of its transparency and computational efficiency, this model is highly suitable for exploring the effects of anthropogenic perturbations such as emissions of greenhouse gases and sulfur dioxide, and land cover changes, on the Indian monsoon. Results of a systematic sensitivity analysis indicate that changes in those parameters which are related to emissions of greenhouse gases lead to an increase in Indian summer rainfall. In contrast, all parameters related to higher atmospheric aerosol concentrations lead to a decrease in Indian rainfall. Similarly, changes in parameters which can be related to forest conversion or desertifieation, act to decrease the summer precipitation. The results indicate that the sign of precipitation changes over India will be dependent on the direction and relative magnitude of different human perturbations.

关键词： Indian monsoon sensitivity analysis global change anthropogenic climate change

Soil water storage,yield,water productivity and transpiration efficiency of soybeans(Glyxine max ***)as affected by soil surface management in lle-Ife,Nigeria

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International Soil and Water conservation Research 2017年第2期5卷 141-150页

作者： Omotayo b.Adeboye bart Schultz Kenneth O.Adekalu Krishna Prasad Department of Agricultural and Environmental Engineering Obafemi Awolowo UniversityIle-IfeNigeria Land and Water Development IHE Delft Institute For Water Education in Partnership with UNESCODelftthe Netherlands Freelance Irrigation and Water Resources Management consultant LalitpurNepal

Rainfed agriculture has a high yield potential if rainfall and land resources are effectively *** this study,conventional(Nc)and six in-situ water conservation practices were used to cultivate Soybean in 2011 and 2012 in Ile-lfe,*** conservation practices are:Tied ridge(TR),Soil bund(bD),Mulch(ML),Mulch plus Soil bund(MLbD),Tied ridge plus Mulch(TRML),Tied ridge plus Soil bund(TRbD).The practices were arranged in Randomised complete block Design with four *** rainfall was 539 and 761 mm in 2011 and 2012,*** soil water storage(SWS)ranged from 485 mm for Nc to 517 mm for TRML in the two *** increased the SWS in the upper 30 cm of the soil by 17% while TR increased the soil water content in the lower 30-60 cm by 22% compared with *** reduced soil temperature in the upper 30 cm between 2.2 and 2.9℃ compared with Nc,TR and *** crop evapotranspiration ranged between 432 mm for Nc and 481 mm for bD in the *** yield increased by 41.7% and 44.3% for bD and MLbD,respectively compared with *** conservation practices increased water productivity for grain yield by 14.0-41.8% compared with ***,it increased average seasonal transpiration efficiency by 15.3-32.5% compared with *** findings demonstrate that when there are fluctuations in rainfall,in-situ water conservation practices improve SWS,land,and water productivity and transpiration efficiency of Soybeans.

关键词： Water conservation Soybean Yield Transpiration Efficiency Evapotranspiration Water productivity

Selection in monoculture vs. mixture alters plant metabolic fingerprints

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Journal of Plant Ecology 2015年第5期8卷 549-557页

作者： Debra Zuppinger-Dingley Dan F.b.Flynn Helmut brandl bernhard Schmid Institute of Evolutionary biology and Environmental Studies University of ZurichWinterthurerstrasse 190CH-8057 ZurichSwitzerland The Arnold Arboretum of Harvard University 1300 Centre StreetBostonMA 02131USA

Aims In grassland biodiversity experiments,positive biodiversity effects on primary productivity increase over *** research has shown that differential selection in monoculture and mixed-species communities leads to the rapid emergence of monoculture and mix-ture types,adapted to their own biotic *** used eight plant species selected for 8 years in such a biodiversity experiment to test if monoculture and mixture types differed in metabolic pro-files using infrared *** Fourier transform infrared spectroscopy(FTIr)was used to assess metabolic fingerprints of leaf samples of 10 individuals of each species from either monocultures or *** FTIr spectra were analyzed using multivariate procedures to assess(i)whether indi-viduals within species could be correctly assigned to monoculture or mixture history based on the spectra alone and(ii)which parts of the spectra drive the group assignment,*** metabolic groups were subject to differential selection in monocultures *** Findings Plant individuals within each of the eight species could be classified as either from monoculture or mixture selection history based on their FTIr *** metabolic groups were differentially selected in the different species;some of them may be related to defense of patho-gens accumulating more strongly in monocultures than in *** rapid selection of the monoculture and mixture types within the eight study species could have been due to a sorting-out process based on large initial genetic or epigenetic variation within the species.

关键词： biodiversity plant evolution selection FTIr spectroscopy metabolic fingerprint

Effect of grain size on dielectric and ferroelectric properties of nanostructured ba_0.8)Sr_(0.2)TiO_(3) ceramics

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Journal of Advanced ceramics 2015年第1期4卷 46-53页

作者： Venkata Ramana MUDINEPALLI Leng FENG Wen-chin LIN b.S.MURTY Department of Physics “National Taiwan Normal University”Taipei 11677TaiwanChina Department of chemistry Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China Nanotechnology Laboratory Department of Metallurgical and Materials EngineeringIndian Institute of Technology-MadrasChennai 600036India

barium strontium titanate( ba_0.8)Sr_(0.2)TiO_(3),bST)nanocrystalline ceramics have been synthesized by high energy ball *** the sintering temperature increases from 1200℃to 1350℃,the average grain size of bST ceramics increases from 86 nm to 123 *** X-ray diffraction(XRD)studies show that these ceramics are *** phase and grain size of the sintered pellets have been estimated from the XRD patterns,scanning electron microscopy(SEM)and transmission electron microscopy(TEM)*** effect of grain size on dielectric and ferroelectric properties is *** dielectric and piezoelectric parameters are greatly improved at room temperature with increase in grain *** curie transition temperature is found to shift slightly towards higher temperatures as the grain increases from 86 nm to 123 *** coercive field decreases and the remnant polarization and spontaneous polarization increase as the grain size of bST nano ceramics *** ceramics are promising materials for tunable capacitor device applications.

关键词： nanocrystalline ceramics lead free ceramics crystallization electron microscopy dielectric properties hysteresis

Marker-Assisted Pyramiding of Genes conferring ResistanceAgainst bacterial blight and blast Diseases into Indian RiceVariety MTU1010

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Rice science 2016年第6期23卷 306-316页

作者： k.arunakumari c.v.durgarani v.satturu k.r.sarikonda p.d.r.chittoor b.vutukuri g.s.laha a.p.k.nelli s.gattu m.jamal a.prasadbabu s.hajira r.m.sundaram Institute of biotechnology Professor Jayashankar Telangana State Agricultural UniversityRajendranagarHyderabad 500030India Andhra Pradesh Rice Research Institute Acharya N.G.Ranga Agricultural UniversityMaruteruWest Godavari District 534122India Agriculture Research Station Acharya N.G.Ranga Agricultural UniversityNellore 524004India crop Improvement Section ICAR-Indian Institute of Rice ResearchRajendranagarHyderabad 500030India Urmatt Ltd.Wang chai Chaingrai 57210Thailand

Two major bacterial blight （bb） resistance genes （Xa21 and xa13） and a major gene for blastresistance （Pi54） were introgressed into an Indian rice variety MTU1010 through marker-assistedbackcross breeding. Improved Samba Mahsuri （possessing Xa21 and xa13） and NLR145 （possessingPi54） were used as donor parents. Marker-assisted backcrossing was continued till bc2 generationwherein PcR based functional markers specific for the resistance genes were used for foregroundselection and a set of parental polymorphic microsatellite markers were used for background selectionat each stage of backcrossing. Selected bc2F1 plants from both crosses, having the highest recoveriesof MTU1010 genome （90% and 92%, respectively）, were intercrossed to obtain intercross F1 （IcF1） plants,which were then selfed to generate 880 IcF2 plants possessing different combinations of the bb andblast resistance genes. Among the IcF2 plants, seven triple homozygous plants （xa13xa13Xa21Xa21Pi54Pi54）with recurrent parent genome recovery ranging from 82% to 92% were identified. All the seven IcF2plants showed high resistance against the bacterial blight disease with a lesion lengths of only 0.53–2.28 cm, 1%–5% disease leaf areas and disease scoring values of ‘1’ or ‘3’. The seven IcF2 plants wereselfed to generate IcF3, which were then screened for blast resistance, and all were observed to behighly resistant to the diseases. Several IcF3 lines possessing high level of resistance against bb andblast, coupled with yield, grain quality and plant type on par with MTU1010 were identified and advanced forfurther selection and evaluation.

关键词： gene pyramiding bacterial blight resistance blast resistance rice marker-assistedbackcross breeding