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Synthesis and Structural Characterization of N,N-disubstituted Acylguanidines

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Chinese Journal of Structural Chemistry 2018年第5期37卷 710-718页

作者：王凡凡侯宪辉朱成奔李海普杨鹰 School of Chemistry and Chemical Engineering Centre for Environment and Water Resource Central South University

A series of five N,N-disubstituted acylguanidines R1C（O）N=C[N（H）R2]NR23（R1=Mes or Ph; R2=Ar′′or Ar′; R3=Cy, Bn, iPr, or Et）（Mes=2,4,6-Me3C6H2, Ar′′=2,6-iPr2C6H3, Ar′=2,6-Me2C6H3） was synthesized from the reactions of parent acylthioureas with respective secondary amines. According to structutral characterization by single-crystal X-ray diffraction, the rough reduction of the steric hindrance of R substitutents of R1 C（O）N=C[N（H）R2]NR23（also abbreviated as R1-R2-R3 for comparison purposes） led to the slight enlongation of N（1）–C（1） bond lengthes and small decrease of N（1）–C（1）–N（3） bond angles from Mes–Ar′′–Cy（1） to Ph–Ar′′–Bn（2）, Ph–Ar′′–iPr（3） and Ph–Ar′–Cy（4）. At the same time, the N（1）–H（1）···O（1） intramolecular hydrogen bonds were observed in these cases. When R3=Et, an interesting compound Ph-Ar′-Et（5） was obtained with the formation of intermolecular hydrogen bonds instead. 1 belongs to the monoclinic system, space group P2（1/n） with a=9.6488（3）, b=28.5318（8）, c=11.9155（3） A, b=91.439（2）°, V=3279.27（16） A3, and Z=4. 2 belongs to the triclinic system, space group P1 with a=9.6759（7）, b=10.8613（8）, c=15.7642（12） A, a=70.429（3）, b=79.257（4）, g=69.052（4）°, V=1453.63（19） A3 and Z=2. 3 belongs to the monoclinic system, space group P2（1/c） with a=11.1393（4）, b=13.0643（4）, c=17.6600（6） A, b=101.866（2）o, V=2515.09（15） A3 and Z=4. 4 belongs to the monoclinic system, space group C2/c with a=17.8466（3）, b=13.6126（2）, c=21.6710（4） A, b=90.7310（10）°, V=4992.72（14） A3 and Z=8. 5 is of orthorhombic system, space group P212121 with a=10.5555（2）, b=11.8913（2）, c=14.9558（4） A, V=1877.23（5） A3 and Z=4.

关键词： acylguanidine acylthiourea intramolecular hydrogen bond

Synthesis and Characterization of Copper(Ⅰ) Halide Complexes with Thiourea and Heterocyclic Thione

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Chinese Journal of Structural Chemistry 2015年第10期34卷 1571-1578页

作者：韩立潘霞李海普杨鹰 School of Chemistry and Chemical Engineering Centre for Environment and Water Resource Central South University

Reactions of N,NA-diisopropyl-thiourea（abbreviated as L1） with CuC l2 and Cu Br2 afforded the trimeric（L1Cu Cl）3（1） and（L1Cu Br）3（2）, respectively, featuring the sulfur bridged Cu3S3 six-membered ring each as the core structure. During the reaction, Cu（Ⅱ） was reduced to Cu（I）. Similarly, the reactions of L1 with Cu Cl and Cu Br gave the same products as those by L1 with respective Cu Cl2 and Cu Br2. In contrast, treatment of 1,3-diisopropyl-4,5-dimethylimidazole-2（3H）-thione（L2） with Cu I led to the formation of sulfur and iodide mixed-bridged complex [（L2）4（Cu I）5]（3）, in which two co-vertice Cu3S2 I six-membered rings were fused by an iodide atom. Compounds obtained were characterized by 1H NMR and 13 C spectroscopy, elemental analysis, and single-crystal X-ray diffraction. 2 belongs to the monoclinic system, space group P21/c with a = 19.6009（10）, b = 11.5069（6）, c = 17.1744（9） A, β = 109.062（3）o, V = 3661.2（3） A3, C21H48Br3Cu3N6S3, Mr = 911.18, Z = 4, Dc = 1.653 Mg/m^3, μ（Mo Kα） = 5.192 mm–1, F（000） = 1824, S = 1.030, the final R = 0.0374 and w R = 0.0808 for 4988 observed reflections（I 2σ（I）） and R = 0.0726 and wR = 0.0916 for all data. 3·2THF belongs to the monoclinic system, space group I2/a with a = 19.7335（6）, b = 13.3544（4）, c = 29.6355（11） A, β = 105.415（2）o, V = 7528.9（4） A3, C52H96Cu5I5N8O2S4, Mr = 1945.81, Z = 4, Dc = 1.717 Mg/m^3, μ（Mo Kα） = 3.589 mm–1, F（000） = 3816, S = 1.034, the final R = 0.0325 and w R = 0.0810 for 5704 observed reflections（I 2σ（I）） and R = 0.0447 and wR = 0.0910 for all data.

关键词： thiourea thione S donor copper

A classification of water erosion models according to their geospatial characteristics

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International Journal of Digital Earth 2014年第3期7卷 229-250页

作者： Christos G.Karydas Panos Panagos Ioannis Z.Gitas School of Forestry and Natural environment Aristotle University of ThessalonikiThessalonikiGreece Joint Research centre of the European Commission Institute for Environment and SustainabilityIspraItaly

In this article,an extensive inventory in the literature of water erosion modelling from a geospatial point of view is *** of scale,spatiality and complexity are explored and clarified in a theoretical *** of Geographic Information Systems(GIS)is pointed out as facilitating data mixing and model rescaling and thus increasing complexity in data-method *** scale,temporal scale and spatial methodologies are addressed as the most determining geospatial properties underlying water erosion *** these properties as classification criteria,82 water erosion models are identified and classified into eight *** a result,a complete overview of water erosion models becomes available in a single *** biggest share of the models is found in the category of the mechanistic pathway-type event-based models for watershed to landscape *** parallel,geospatial innovations that could be considered as milestones in water erosion modelling are highlighted and *** alphabetical list of all models is also listed in the *** manipulating scale efficiently,two promising spatial theories are suggested for further exploitation in the future such as hierarchy theory and fractals *** erosion applications,uncertainty analysis within GIS is considered to be necessary for further improving performance of erosion models.

关键词： erosion geospatial model classification digital earth

Revisiting study on Boussinesq modeling of wave transformation over various reef profiles

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Water Science and Engineering 2014年第3期7卷 306-318页

作者： Ke-zhao FANG Ji-wei YIN Zhong-bo LIU Jia-wen SUN Zhi-li ZOU State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology National Marine environment Monitoring Center State Oceanic Administration Heilongjiang Province Navigation investigation and Design Institute

To better understand the complex process of wave transformation and associated hydrodynamics over various fringing reef profiles, numerical experiments were conducted with a one-dimensional （1D） Boussinesq wave model. The model is based on higher-order Boussinesq equations and a higher-accuracy finite difference method. The dominant energy dissipation in the surf zone, wave breaking, and bottom friction were considered by use of the eddy viscosity concept and quadratic bottom friction law, respectively. Numerical simulation was conducted for a wide range of wave conditions and reef profiles. Good overall agreement between the computed results and the measurements shows that this model is capable of describing wave processes in the fringing reef environment. Numerical experiments were also conducted to track the source of underestimation of setup for highly nonlinear waves. Linear properties （including dispersion and shoaling） are found to contribute little to the underestimation; the low accuracy in nonlinearity and the ad hoc method for treating wave breaking may be the reason for the problem.

关键词： wave-induced setup, wave-induced setdown Boussinesq model wave breaking, reef

Do concentrations in eggs and liver tissue tell the same story of temporal trends of mercury in high Arctic seabirds?

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Journal of environmental Sciences 2018年第6期30卷 65-72页

作者： Mark L.Mallory Birgit M.Braune Biology Department Acadia University environment and Climate Change Canada National Wildlife Research Centre Carleton University

Mercury（Hg） remains a key contaminant of concern in Arctic biota, and monitoring of Hg concentrations in seabird tissues will be an effective approach to track the effects of implementing the Minamata Convention. We examined trends in total Hg（THg） in liver and egg tissues of two Arctic seabirds, thick-billed murres（Uria lomvia） and northern fulmars（Fulmarus glacialis）, between 1976 and 2013 to assess whether both tissues showed similar patterns of Hg change. Hepatic THg was consistently higher than egg THg, and both species had similar egg THg concentrations, but fulmars had higher hepatic THg than *** THg concentrations showed more relative variation through time than *** suggest that egg THg better reflects exposure of birds to THg in local, Arctic prey,whereas liver THg may incorporate longer term, year-round THg exposure. Additional analysis of THg distribution in Arctic seabirds post-laying would help inform interpretation of long-term trends.

关键词： Canada Fulmarus glacialis Northern fulmar Thick-billed murre Uria lomvia

Application of nanoparticle tracking analysis for characterising the fate of engineered nanoparticles in sediment-water systems

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Journal of environmental Sciences 2018年第2期30卷 62-71页

作者： Ping Luo Alejandro Roca Karen Tiede Katie Privett Jiachao Jiang John Pinkstone Guibin Ma Jonathan Veinot Alisatair Boxall School of environment Science and Spatial informatics Chinese University of Mining and Technology Department of Physics University of York centre for Chemical Safety and Stewardship (CCSS) Food and Environment Research Agency (FERA) environment Department University of York Department of Chemistry University of Alberta

Novel applications of nanotechnology may lead to the release of engineered nanoparticles（ENPs）, which result in concerns over their potential environmental hazardous impact. It is essential for the research workers to be able to quantitatively characterise ENPs in the environment and subsequently to assist the risk assessment of the ENPs. This study hence explored the application of nanoparticle tracking system（NTA） to quantitatively describe the behaviour of the ENPs in natural sediment-water systems. The NTA allows the measurement of both particle number concentration（PNC） and particle size distribution（PSD） of the ENPs. The developed NTA method was applied to a range of gold and magnetite ENPs with a selection of surface properties. The results showed that the positively-charged ENPs interacted more strongly with the sediment than neutral and negatively-charged ENPs. It was also found that the citrate coated Au ENPs had a higher distribution percentage（53%） than 11-mercaptoundecanoic acid coated Au ENPs（20%） and citrate coated magnetite ENPs（21%）. The principles of the electrostatic interactions between hard（and soft） acids and bases（HSAB） are used to explain such behaviours; the hard base coating（i.e. citrate ions） will interact more strongly with hard acid（i.e. magnetite） than soft acid（i.e. gold）.The results indicate that NTA is a complementary method to existing approaches to characterise the fate and behaviour of ENPs in natural sediment.

关键词： Quantitative characterisation Hard and soft acids and bases Fate of engineered nanoparticles Nanoparticle tracking system Particle number concentration Particle size distribution

Hazards from lakes and reservoirs: new interpretation of the Vaiont disaster

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Journal of Mountain Science 2022年第6期19卷 1717-1737页

作者： Alan P.DYKES Edward N.BROMHEAD centre for Engineering Environment and Society ResearchSchool of Engineering and the EnvironmentKingston UniversityPenrhyn RoadKingston upon ThamesKTi 2EEUK

Hazards in reservoirs and lakes arising from subaerial landslides causing impact waves(or ‘lake tsunamis’) are now well known, with several recent examples having been investigated in detail. The potential scale of such hazards was not widely known at the time of the Vaiont dam project in the 1950s and early 1960s, although a small wave triggered by a landslide at another new reservoir nearby in the Dolomites(northern Italy) drew the possible hazard to the attention of the Vaiont project’s managers. The Vaiont disaster in 1963 arose from a combination of disparate and seemingly unrelated factors and circumstances that led to an occurrence that could not have been imagined at that time. The ultimate cause was a very large landslide moving very rapidly into a reservoir and displacing the water. The resulting wave overtopped the dam to a height of around 175 m and around 2000 people were killed. This paper identifies and examines all of the issues surrounding the Vaiont dam and landslide in order to identify causal factors, contributory factors(including aggravating factors) and underlying factors. In doing so, it demonstrates that the disaster arose from the Vaiont dam project and cannot be attributed simply to the landslide. Underlying geological factors gave rise to the high speed of the landslide, which would have occurred anyway at some time. However, without the contributory factors that account for the presence of the reservoir, i.e. the choice of location for the project and management of the project with respect to a possible landslide hazard, there would have been no disaster. Indeed, the disaster could have been avoided if the reservoir could have been emptied pending further ground investigations. Understanding of this case provides many lessons for future dam projects in mountainous locations but also highlights an ongoing and perhaps under-appreciated risk from similar events involving other water bodies including geologically recent lakes formed behind n

关键词： Vaiont landslide Impulse wave Lake tsunami Dam project Causal factors for disaster

Downscaling Landsat-8 land surface temperature maps in diverse urban landscapes using multivariate adaptive regression splines and very high resolution auxiliary data

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International Journal of Digital Earth 2020年第8期13卷 899-914页

作者： Joanna Zawadzka Ron Corstanje Jim Harris Ian Truckell centre for environmental and Agricultural Informatics School of WaterEnergy and EnvironmentCranfield UniversityBedfordshireUK

We propose a method for spatial downscaling of Landsat 8-derived LST maps from 100(30 m)resolution down to 2–4 m with the use of the Multiple Adaptive Regression Splines(MARS)models coupled with very high resolution auxiliary data derived from hyperspectral aerial imagery and large-scale topographic *** applied the method to four Landsat 8 scenes,two collected in summer and two in winter,for three British towns collectively representing a variety of urban *** used several spectral indices as well as fractional coverage of water and paved surfaces as LST predictors,and applied a novel method for the correction of temporal mismatch between spectral indices derived from aerial and satellite imagery captured at different dates,allowing for the application of the downscaling method for multiple dates without the need for repeating the aerial *** results suggest that the method performed well for the summer dates,achieving RMSE of 1.40–1.83 K prior to and 0.76–1.21 K after correction for *** conclude that the MARS models,by addressing the non-linear relationship of LST at coarse and fine spatial resolutions,can be successfully applied to produce high resolution LST maps suitable for studies of urban thermal environment at local scales.

关键词： Land surface temperature downscaling urban multivariate adaptive regression splines remote sensing

Comparison between wave generation methods for numerical simulation of bimodal seas

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Water Science and Engineering 2016年第1期9卷 3-13页

作者： Daniel A.Thompson Harshinie Karunarathna Dominic Reeve Energy & environment Research Group Zienkiewicz Centre for Computational Engineering Swansea UniversityBay Campus

This paper describes an investigation of the generation of desired sea states in a numerical wave model. Bimodal sea states containing energetic swell components can be coastal hazards along coastlines exposed to large oceanic fetches. Investigating the effects of long-period bimodal seas requires large computational domains and increased running time to ensure the development of the desired sea state. Long computational runs can cause mass stability issues due to the Stokes drift and wave reflection, which in turn affect results through the variation of the water level. A numerical wave flume, NEWRANS, was used to investigate two wave generation methods： the wave paddle method, allowing for a smaller domain; and the internal mass source function method, providing an open boundary allowing reflected waves to leave the domain. The two wave generation methods were validated against experimental data by comparing the wave generation accuracy and the variance of mass in the model during simulations. Results show that the wave paddle method not only accurately generates the desired sea state but also provides a more stable simulation, in which mass fluctuation has less of an effect on the water depth during the long-duration simulations. As a result, it is suggested that the wave paddle method with active wave absorption is preferable to the internal wave maker option when investigating intermediate-depth long-period bimodal seas for long-duration simulations.

关键词： Wave modeling Wave generation RANS Swell wave Bimodal sea Long-period waves