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Monitoring real time polymorphic transformation of sulfanilamide by diffuse reflectance visible spectroscopy

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journal of Pharmaceutical Analysis 2016年第3期6卷 179-183页

作者： Tracy O.Ehiwe Bruce D.Alexander john C.Mitchell Martin j.Snowden Laura j.Waters Medway Centre for Formulation Science Faculty of Engineering and Science University of Greenwich at Medway School of Applied Sciences University of Huddersfield

This study investigated the development of a novel approach to surface characterization of drug poly- morphism and the extension of the capabilities of this method to perform ＇real time＇ in situ measure- ments. This was achieved using diffuse reflectance visible （DRV） spectroscopy and dye deposition, using the pH sensitive dye, thymol blue （TB）. Two polymorphs, SFN-β and SFN-γ, of the drug substance sulfanilamide （SFN） were examined. The interaction of adsorbed dye with polymorphs showed different behavior, and thus reported different DRV spectra. Consideration of the acid/base properties of the morphological forms of the drug molecule provided a rationalization of the mechanism of differential coloration by indicator dyes. The kinetics of the polymorphic transformation of SFN polymorphs was monitored using treatment with TB dye and DRV spectroscopy. The thermally-induced transformation fitted a first-order solid-state kinetic model （R2=0.992）, giving a rate constant of 2.43 × 10^- 2 s 1.

关键词： Polymorphic transformation Sulfanilamide Diffuse reflectance visible spectroscopy Powder X-ray diffraction Differential scanning calorimetry

Deep convolutional Ritz method: parametric PDE surrogates without labeled data

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Applied Mathematics and Mechanics(English Edition) 2023年第7期44卷 1151-1174页

作者： j.N.FUHG A.KARMARKAR T.KADEETHUM H.YOON N.BOUKLAS Sibley School of Mechanical and Aerospace Engineering Cornell UniversityNew York 14853U.S.A Geomechanics Department Sandia National LaboratoriesAlbuquerque 87123U.S.A.

The parametric surrogate models for partial differential equations(PDEs)are a necessary component for many applications in computational sciences,and the convolutional neural networks(CNNs)have proven to be an excellent tool to generate these surrogates when parametric fields are *** are commonly trained on labeled data based on one-to-one sets of parameter-input and PDE-output ***,residual-based deep convolutional physics-informed neural network(DCPINN)solvers for parametric PDEs have been proposed to build surrogates without the need for labeled *** allow for the generation of surrogates without an expensive *** this work,we present an alternative formulation termed deep convolutional Ritz method(DCRM)as a parametric PDE *** approach is based on the minimization of energy functionals,which lowers the order of the differential operators compared to residualbased *** on studies involving the Poisson equation with a spatially parameterized source term and boundary conditions,we find that CNNs trained on labeled data outperform DCPINNs in convergence speed and generalization *** surrogates generated from the DCRM,however,converge significantly faster than their DCPINN counterparts,and prove to generalize faster and better than the surrogates obtained from both CNNs trained on labeled data and *** hints that the DCRM could make PDE solution surrogates trained without labeled data possibly.

关键词： physics-informed constraint physics-informed neural network(PINN) deep energy network convolutional neural network(CNN)

Strategic comparison of membrane-assisted and membrane-less water electrolyzers and their potential application in direct seawater splitting(DSS)

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Green Energy & Environment 2023年第4期8卷 989-1005页

作者： Abdul Malek Xu Lu Paul R.Shearing Dan j.L.Brett Guanjie He Clean Combustion Research Center(CCRC) Physical Science and Engineering Division(PSE)King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Kingdom of Saudi Arabia KAUST Solar Center(KSC) Physical Science and Engineering Division(PSE)King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Kingdom of Saudi Arabia School of Engineering and Materials Science Queen Mary University of LondonMile End RoadLondon E14NSUK Department of Chemical Engineering University College London(UCL)Gower StLondon WC1E 6BTUnited Kingdom

Electrocatalytic splitting of water by means of renewable energy as the electricity supply is one of the most promising methods for storing green renewable energy as hydrogen. Although two-thirds of the earth’s surface is covered with water, there is inadequacy of freshwater in most parts of the world. Hence, splitting seawater instead of freshwater could be a truly sustainable alternative. However, direct seawater splitting faces challenges because of the complex composition of seawater. The composition, and hence, the local chemistry of seawater may vary depending on its origin, and in most cases, tracking of the side reactions and standardizing and customizing the catalytic process will be an extra challenge. The corrosion of catalysts and competitive side reactions due to the presence of various inorganic and organic pollutants create challenges for developing stable electro-catalysts. Hence, seawater splitting generally involves a two-step process, i.e., purification of seawater using reverse osmosis and then subsequent fresh water splitting. However, this demands two separate chambers and larger space, and increases complexity of the reactor design. Recently, there have been efforts to directly split seawater without the reverse osmosis step. Herein, we represent the most recent innovative approaches to avoid the two-step process, and compare the potential application of membrane-assisted and membrane-less electrolyzers in direct seawater splitting(DSS). We particularly discuss the device engineering, and propose a novel electrolyzer design strategies for concentration gradient based membrane-less microfluidic electrolyzer.

关键词： Electrocatalytic seawater splitting Direct seawater splitting Osmosis Concentration cells Membrane-less electrolyzer Microfluidic electrolyzer

Do specific ultrasonography features identified at the time of early pregnancy loss predict fetal chromosomal abnormality? e A systematic review and meta-analysis

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Genes & Diseases 2019年第2期6卷 129-137页

作者： j.Huang W.Zhu j.Tang S.H.Saravelos L.C.Y.Poon T.C.Li Department of Obstetrics and Gynaecology The First Affiliated Hospital of Chongqing Medical UniversityChongqing400016China Department of Obstetrics and Gynaecology The Chinese University of Hong KongHong Kong SARChina IVF Unit Hammersmith HospitalImperial College Healthcare NHS TrustLondonUK

To investigate the association of specific ultrasonography features identified during the diagnosis of early pregnancy loss(EPL)and abnormal *** was a systematic review and meta-analysis conducted in accordance with PRISMA *** searched PubMed,Cochrane and Ovid MEDLINE from 1977 to jan 2017 to identify the articles that described EPL with karyotype and ultrasonography *** differences were pooled to estimate the chromosomal abnormality rates in ultrasonography features,including pre-embryonic,enlarged yolk sac(YS),short crown rump length(CRL),small gestational sac(GS),symmetrical arrested growth embryo,or gestational sac with only a *** assessment of included studies was performed using Strengthening the Reporting of Observational Studies in Epidemiology(STROBE)checklists for Observational Studies(2007 version).Thirteen studies were included in the *** abnormality was more likely to occur in embryonic EPL and enlarged *** the other hand,short CRL,small GS,symmetrical arrested growth embryo,or gestational sac with only a YS,were not associated with an increased risk of fetal chromosomal *** features at the time of diagnosis of EPL have limited predictive value of fetal chromosomal abnormality.

关键词： Ultrasonography Early pregnancy loss Chromosomal abnormality Predictive value

Predict sandstone distribution by integrated study of deformed shale using borehole image and seismic data,a case study from northern Gulf of Mexico

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Petroleum Research 2020年第2期5卷 103-111页

作者： W.W.Xu B.Winkelman T.Wilkinson A.Kumar L.Chen R.Hayden j.Gendur R.Hearn D.Shan j.Meyer j.A.Canas O.Mullins Schlumberger(retired) HoustonUSA Talos Energy LLC(retired) HoustonUSA Schlumberger HoustonUSA Kosmos Energy HoustonUSA

Many Upper Tertiary reservoirs from the Gulf of Mexico(GoM)are sandstones deposited either in channel-levee systems or lobe systems in the intra-slope deepwater *** of the major uncertainties about those reservoirs is their distribution,which is likely controlled by salt *** current salt structure,however,does not represent the salt structure when the sands were *** is difficult,if not impossible,to restore the salt history based on current salt *** movement resulted in a great amount of deformed shale in *** images on the other hand can be used to characterize the internal structure or texture of deformed shale;and the dips of deformed shale from borehole images may be used to define the paleo slope direction,which controls the movement of deformed *** internal structure or texture of deformed shale,therefore,may provide some information about the history of salt movement,which may also control the sand *** this integrated study,all the available data,including borehole images,seismic volumes,and other petrophysical logs,were used to characterize the reservoir sands and *** reservoir sands are mainly composed of amalgamated sand,layered sand,and laminated *** on dips from borehole images,paleo flow directions of reservoir sands were *** shales are categorized as hemipelagic shale and deformed *** hemipelagic shale has relatively lower and consistent dips;whereas deformed shale has relatively higher variable in both dip magnitude and dip *** integrated study suggests the main reservoir of the field is submarine lobe sands deposited above an allochthonous salt in the *** evacuation of the salt body below the basin created small geographic lower area for sand lobes to *** dips from the deformed shale provided information about the center of the small(or mini)basin,thus established a relationship between the dip pattern and sandstone distribut

关键词： Mass transport deposit Gulf of Mexico Sedimentology Borehole image Integration

光谱探针法确定Eu^(3+):ThO_2的格位对称性及选择激发下样品的光致发光研究

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物理学报 2000年第9期49卷 1859-1866页

作者：尹民 j.C. KRUPA 中国科学技术大学结构研究开放实验室合肥230026 法国国家科学研究中心Orsay核物理研究所

测量和分析了不同温度下Eu3 + :ThO2 的激发光谱、发射光谱和荧光衰减曲线 .Eu3 + :ThO2 晶体是用熔融法生长的 .通过 12K下格位选择激发下的发射光谱测量 ,利用晶场理论 ,确定了Eu3 + 在ThO2 占据Oh 和C3v两种格位 .列表给出了两种格位... 详细信息

测量和分析了不同温度下Eu3 + :ThO2 的激发光谱、发射光谱和荧光衰减曲线 .Eu3 + :ThO2 晶体是用熔融法生长的 .通过 12K下格位选择激发下的发射光谱测量 ,利用晶场理论 ,确定了Eu3 + 在ThO2 占据Oh 和C3v两种格位 .列表给出了两种格位Eu3 + 离子的晶场能级和室温及 12K下的荧光寿命 .讨论了温度对能量传递过程的影响以及低温下激发峰红移的机理 .

关键词：光谱探针选择激光光谱氧化钍格位对称性发光

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Guest Editorial

Digital Communications and Networks 2022年第6期8卷 865-867页

作者： Honghao Gao Ramon j.Duran Barroso Zhiyuan Tan School of Computer Engineering and Science Shanghai UniversityChina Universidad de Valladolid Spain School of Computing Edinburgh Napier UniversityUK

Special issue on Collaborative computing to information fusion for5GIoTsocialdata With the development of 5G IoT technology,a large amount of social data is generated every *** to handle these social data has become a critical *** Fusion with Collaborative Computing aims to help academia and industry understand data,information and ***,in this special issue,we selected the following highquality papers from open submissions.A summary is outlined below.

关键词： handle problem IoT

Calculation and interpretation of classical turning surfaces in solids

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npj Computational Materials 2021年第1期7卷 229-238页

作者： Aaron D.Kaplan Stewart j.Clark Kieron Burke john P.Perdew Department of Physics Temple UniversityPhiladelphiaPA 19122USA Centre for Materials Physics Durham UniversityDurham DH13LEUK Departments of Chemistry and Physics University of CaliforniaIrvineCA 92697USA Departments of Physics and Chemistry Temple UniversityPhiladelphiaPA 19122USA

Classical turning surfaces of Kohn–Sham potentials separate classically allowed regions(CARs)from classically forbidden regions(CFRs).They are useful for understanding many chemical properties of molecules but need not exist in solids,where the density never decays to *** equilibrium geometries,we find that CFRs are absent in perfect metals,rare in covalent semiconductors at equilibrium,but common in ionic and molecular *** all materials,CFRs appear or grow as the internuclear distances are uniformly *** can also appear at a monovacancy in a *** with several approximate density functionals and codes confirm these behaviors.A classical picture of conduction suggests that CARs should be connected in metals,and disconnected in wide-gap insulators,and is confirmed in the limits of extreme compression and ***,many semiconductors have no CFR at equilibrium,a key finding for density functional ***,a strong correlation with insulating behavior can still be ***,equilibrium bond lengths for all cases can be estimated from the bond type and the sum of the classical turning radii of the free atoms or ions.

关键词： turning solids expanded

Can active late-type stars contribute to the Galactic lithium abundance?

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Research in Astronomy and Astrophysics 2020年第7期20卷 127-133页

作者： Darnell E.Kelly Damian j.Christian Mihalis Mathioudakis Darko jevremovi′c Department of Physics and Astronomy California State UniversityNorthridgeCA 91330-8268USA Astrophysics Research Centre School of Mathematics and PhysicsQueen’s University BelfastBelfast BT71NNUK Astronomical Observatory Volgina 711060 BelgradeSerbia

Lithium abundances in our Galaxy and especially 6 Li abundances provide important constraints on our understanding of Big Bang Nucleosynthesis(BBNS),stellar evolution and the creation of light elements by cosmic rays in the ISM.~6 Li has been detected in energetic solar events,one chromospherically active binary and several dwarf halo *** our work on active late-type stars with high lithium abundances,we expand our study to consider if the flare origin of lithium created by spallation can contribute significantly to the Galactic abundance of *** previously derived ~6 Li/~7 Li=0.030 ± 0.010 for active K dwarf Gj 117 using VLT UVES *** find^6 Li/~7 Li ratios of 0.02 and 0.10 for two other stars in our sample,Gj 182 and EUVE j1145-55.3 A,*** that these later type,active stars have significant flare rates and stellar winds,we have estimated the contribution of these stars to the Galactic lithium *** that K and M stars comprise over 84% of our Galaxy and that many of these can have significant stellar winds,we conclude that spallation in stellar flares can contribute 1% and up to 5% of the Galactic lithium abundance.

关键词： stars:abundances stars:activity Galaxy:abundances