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On Real Reward Testing

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Journal of Shanghai Jiaotong university(Science) 2011年第4期16卷 479-484页

作者：杨伟忠邓玉欣 MOE-ms Key Laboratory for Intelligent Computing and Intelligent Systems Shanghai Jiaotong University

We extend the traditional nonnegative reward testing with negative *** this new testing framework,may preorder and must preorder are the inverse of each *** surprisingly,it turns out that the real reward must testing is no more powerful than the nonnegative reward testing,at least for finite processes. In order to prove that result,we exploit an important property of failure simulation about the inclusion of the testing outcomes between two related processes.

关键词： probabilistic processes real reward testing nonnegative reward testing failure simulation

THE EARLY INFLUENCE OF PETER LAX ON COMPUTATIONAL HYDRODYNAMICS AND AN APPLICATION OF LAX-FRIEDRICHS AND LAX-WENDROFF ON TRIANGULAR GRIDS IN LAGRANGIAN COORDINATES

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Acta Mathematica Scientia 2011年第6期31卷 2195-2202页

作者： Richard Liska Mikhail Shashkov Burton Wendroff Faculty of Nuclear Sciences and Physical Engineering Czech Technical University in Prague Group XCP-4 MS-F644Los Alamos National Laboratry Group T-5 MS-B284Los Alamos National Laboratry

We give a brief discussion of some of the contributions of Peter Lax to Com- putational Fluid Dynamics. These include the Lax-Friedrichs and Lax-Wendroff numerical schemes. We also mention his collaboration in the 1983 HLL Riemann solver. We de- velop two-dimensional Lax-Friedrichs and Lax-Wendroff schemes for the Lagrangian form of the Euler equations on triangular grids. We apply a composite scheme that uses a Lax- Friedrichs time step as a dissipative filter after several Lax-Wendroff time steps. Numerical results for Noh＇s infinite strength shock problem, the Sedov blast wave problem, and the Saltzman piston problem are presented.

关键词： Lax-Friedrichs Lax-Wendroff conservation laws Lagrangian coordinates,triangular grid

Stereoselective synthesis of vic-halohydrins and an unusual Knoevenagel product from an organocatalyzed aldol reaction:A non-enamine mode

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催化学报 2015年第7期36卷 1093-1100页

作者： P.B.Thorat S.V.Goswami V.P.Sondankar S.R.Bhusare DepartmentofChemistry DnyanopasakCollegeParbhani-431401MSIndia

Stereoselective synthesis by an aldol reaction between chloroacetone and aldehyde was studied using a synthesized chiral organocatalyst and triethylamine. The reaction gave α-chloro-β-hydroxy ketones in excellent yield with high anti selectivity and enantioselectivity. The chiral organocatalyst was also used in the Knoevenagel reaction, which gave α-cyano-β-hydroxy ketones at a low temperature and the usual Knoevenagel product at a high temperature. Both products were obtained in good to moderate yield with good anti selectivity in the case of α-cyano-β-hydroxy ketone derivatives.

关键词：立体选择性合成羟醛缩合反应 Knoevenagel反应产品卤代醇有机催化剂烯胺维纳

Mitigation of atrazine,S-metolachlor,and diazinon using common emergent aquatic vegetation

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Journal of Environmental Sciences 2017年第6期29卷 114-121页

作者： Matthew T.Moore Martin A.Locke Robert Krǒger Water Quality and Ecology Research Unit USDA Agricultural Research ServiceNational Sedimentation LaboratoryOxfordMS 38655USA

By the year 2050, the population of the United States is expected to reach over 418 million, while the global population will reach 9.6 billion. To provide safe food and fiber, agriculture must balance pesticide usage against impacts on natural resources. Challenges arise when storms cause runoff to be transported to aquatic receiving systems. Vegetated systems such as drainage ditches and constructed wetlands have been proposed as management practices to alleviate pesticide runoff. Twelve experimental mesocosms （1.3 ±0.71 ± 0.61 m） were filled with sediment and planted with a monoculture of one of three wetland plant species （Typha latifolia, Leersia oryzoides, and Sparganium arnericanurn）. Three mesocosms remained unvegetated to serve as controls. All mesocosms were amended with 9.2 ± 0.8 μg/L, 12 ± 0.4 μg/L, and 3.1 ± 0.2 μg/L of atrazine, metolachlor, and diazinon, respectively, over a 4 hr hydraulic retention time to simulate storm runoff. Following the 4 hr amendment, non-amended water was flushed through mesocosms for an additional 4 hr. Outflow water samples were taken hourly from pre-amendment through 8 hr, and again at 12, 24, 48, 72, and 168 hr post-amendment. L. oryzoides and T. latifolia had mean atrazine, metolachlor, and diazinon retentions from B1%-55% for the first 4 hr of the experiment. Aside from S. arnericanum and atrazine （25% retention）, unvegetated controls had the lowest pesticide retention （17%-28%） of all compared mesocosms. While native aquatic vegetation shows promise for mitigation of pesticide runoff, further studies increasing the hydraulic retention time for improved efficiency should be examined.

关键词： Phytoremediation Pesticide Mesocosm Wetland

Synthesis, Thermal, Electrical and Catalytic Studies of Some Transition Metal Polychelates of Bis-bidentate Schiff Base

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Chinese Journal of Chemistry 2007年第2期25卷 154-158页

作者： BANSOD, Ashish ASWAR, Anand Department of Chemistry S.G.B. Amravati University Amravati -444602 (MS.) India

Polychelates of Mn（Ⅱ）, Fe（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Zn（Ⅱ） and Cd（Ⅱ） with the bis salen-type ligand derived from 4,4＇-bis[（salicylaldehyde-5）azo]biphenyl and 1,4-diaminobutane have been synthesized. All the polychelalls have been characllrized by elemental analysis, magnetic susceptibility measurements, IR, electronic spectra and thennogravirncuic studies. All the complexes isolated in solid stall are dark coloured and insoluble in water and common organic solvents. The ligand behaves as a bis-bidentall molecule coordinating through the phenolic oxygen and azomethine nitrogen atoms. The thermal decomposition of these metal complexes was investigated by thermogravimetric analysis and data have been analyzed for kinetic parameters using Broido equation. The solid-state electrical conductivity of the ligand and its polychelalls in the form of compressed pellet was studied in the temperaturc range from 313 to 413 K All the polychelalls were found to show semiconducting nature. The Mn（Ⅱ）, Fe（Ⅱ）, Co（Ⅱ） and Ni（Ⅱ） polychelalls have been assessed for the catalytic epoxidation of styrene.

关键词： Schiff base polychelate TGA solid-state conductivity catalytic activity

Continental crust formation at arcs, the arclogite ‘‘delamination''cycle, and one origin for fertile melting anomalies in the mantle

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Science Bulletin 2015年第13期60卷 1141-1156页

作者： Cin-Ty A.Lee Don L.Anderson Department of Earth Science MS-126 Rice University Department of Geological and Planetary Sciences California Institute of Technology

The total magmatic output in modern arcs,where continental crust is now being formed, is believed to derive from melting of the mantle wedge and is largely basaltic. Globally averaged continental crust, however, has an andesitic bulk composition and is hence too silicic to have been derived directly from the mantle. It is well known that one way this imbalance can be reconciled is if the parental basalt differentiates into a mafic garnet pyroxenitic residue/cumulate(‘‘arclogite'') and a complementary silicic melt, the former foundering or delaminating into the mantle due to its high densities and the latter remaining as the *** the Sierra Nevada batholith in California as a case study, the composition of mature continental arc crust is shown in part to be the product of a cyclic process beginning with the growth of an arclogite layer followed by delamination of this layer and post-delamination basaltic underplating/recharge into what remains of the continental crust.A model is presented, wherein continuous arc magmatism and production of arclogites in continental arcs are periodically punctuated by a delamination event and an associated magmatic pulse every *10–30 My. The recycling flux of arclogites is estimated to be *5 %–20 % that of oceanic crust recycling by subduction. Delaminated arclogites have the necessary trace-element compositions to yield time-integrated isotopic compositions similar to those inferred toexist as reservoirs in the mantle. Because of their low melting temperatures, such pyroxenites may be preferentially melted, possibly forming a component of some hotspot magmas.

关键词： Pyroxenite Eclogite Delamination Cumulate Continental crust

Improving cover and management factor (C-factor) estimation using remote sensing approaches for tropical regions

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International Soil and Water Conservation Research 2019年第4期7卷 325-334页

作者： André Almagro Thais Caregnatto Thomé Carina Barbosa Colman Rodrigo Bahia Pereira José Marcato Junior Dulce Buchala Bicca Rodrigues Paulo Tarso Sanches Oliveira Federal University of Mato Grosso do Sul CxP 549 Campo Grande MS 79070-900 Brazil

The Revised Universal Soil Loss Equation (RUSLE)'s cover and management factor (C-factor) is one of the most difficult factors to obtain,mainly because long-term monitoring soil erosion plots under natural rainfall are ***,remote sensing approaches have been used as an alternative for obtaining this ***,there is a lack of studies comparing values of this factor computed from remote sensing approaches with measured *** this study,we compare two widely used remote sensing approaches (CrA and CVK) to estimate the C-factor based on the Normalized Difference Vegetation Index (NDVI) with the literature (CLIT) and field experimental data..We also investigated the influence of C-factor methods on the prediction of soil loss and sediment yield (SY) using measured data in the Guariroba basin,Central-West *** obtained mean C-factor values of 0.032,0.023 and 0.137 for CLIT,CrA and CVK,*** found an average annual soil loss of 2.20 tha-1 yr-1,2.02 t ha-1 yr-1 and 10.07 tha-1 yr-1 and SY values of 6875 tyr-1,6468 tyr-1 and 33,435 t yr1,for CLIT,CrA and CVK *** results indicated a significant improvement in soil loss and SY estimations by using the CrA approach developed for tropical regions,with a bias of 13% to the measured SY (5709tyr-1).We conclude that the CrA method present the most suitable alternative to compute soil loss and SY in tropical ***,this approach allows large-scale evaluation and temporal monitoring,therefore enhancing multi spatial and temporal assessment of soil erosion processes.

关键词： Soil erosion RUSLE NDVI Landsat 8 Land use/land cover

ZrOCl_2·8H_2O catalyzed solvent-free synthesis of isobenzofuran-1(3H)-ones

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Chinese Chemical Letters 2011年第2期22卷 163-166页

作者： Jaiprakash N.Sangshetti Siddique Akber M.K.Ansari Devanand B.Shinde Department of Chemical Technology Dr.Babasaheb Ambedkar Marathwada UniversityAurangabad 431004(MS)India

ZrOCl2·8H2O catalyzed environmentally benign synthesis of isobenzofuran-1（3H）-ones are ***2·8H2O appeared to be an excellent catalyst for the condensation and *** of phthalaldehydic acid（2-carboxybenzaldehyde） with methylaryl and cyclic ketones was initiated by condensation and occurred in one step providing excellent yields（90-98%）.

关键词： 2-Carboxybenzaldehyde Methylaryl and cyclic ketones ZrOCl_2·8H_2O catalyst

Subgroup comparison of COVID-19 case and mortality with associated factors in Mississippi: findings from analysis of the first four months of public data

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The Journal of Biomedical Research 2020年第6期34卷 446-457页

作者： Lei Zhang Stephanie T.McLeod Rodolfo Vargas Xiaojian Liu Dorthy K.Young Thomas E.Dobbs Office of Health Data and Research Mississippi State Department of HealthJacksonMS 39215USA School of Social Work College of Education and Human Sciencesthe University of Southern MississippiHattiesburgMS 39406USA Office of Health Data Operationsand ResearchMississippi State Department of HealthJacksonMS 39215USA Office of State Health Officer Mississippi State Department of HealthJacksonMS 39215USA.

We compared subgroup differences in COVID-19 case and mortality and investigated factors associated with case and mortality rate(MR)measured at the county level in *** were based on data published by the Mississippi State Department of Health between March 11 and July 16,*** COVID-19 case rate and case fatality rate(CFR)differed by gender and race,while MR only differed by *** aged 80 years or older and those who live in a non-metro area had a higher case rate,CFR,and *** controlling for selected factors,researchers found that the percent of residents who are obese,low income,or with certain chronic conditions were associated with the county COVID-19 case rate,CFR,and/or MR,though some were negatively *** findings may help the state to identify counties with higher COVID-19 case rate,CFR,and MR based on county demographics and the degree of its chronic conditions.

关键词： COVID-19 case rate case fatality rate mortality rate