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An efficient method for the N-arylation of phenylurea via copper catalyzed amidation

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Chinese Chemical Letters 2011年第6期22卷 675-678页

作者： Sandip N.Gavade Ravi S.Balaskar Madhav S.Mane Pramod N.Pabrekar Murlidhar S.Shingare Dhananjay V.Mane Organic Research Laboratory S.C.S.College Omerga-413 606MSIndia V.G.Vaze College Mulund(E) Mumbai-400081MSIndia Department of Chemistry Dr.Babasaheb Ambedkar Marathwada University

The coupling reaction of phenylurea with different functionalized aryl halides in the presence of air stable CuI,N,N-dimethylethylenediamine as a ligand,and K_3PO_4 as a base gives symmetrical and unsymmetrical diarylureas in relatively high *** method is milder than the palladium catalyzed arylation and avoids the use of toxic phosphine ligands.

关键词： Copper catalyst Urea Aryl halides Amidation

DEPTH-AVERAGED 2-D CALCULATION OF FLOW AND SEDIMENT TRANSPORT IN CURVED CHANNELS

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International Journal of Sediment Research 2004年第4期19卷 241-257页

作者： Sam S. Y. WANG Director Distinguished Professor ms 38677 National Center for Computational Hydroscience and Engineering The University of Mississippi USA

The helical flow significantly affects the flow, sediment transport and morphological evolution in curved channels. A semi-empirical formula is proposed to determine the cross-stream distribution of the helical flow intensity in the developed regions of a channel bend. It is then used to evaluate the dispersion terms in the depth-averaged 2-D momentum equations and suspended-load transport equation as well as the bed-load transport angle, thus enhancing the depth-averaged 2-D model to account for the effect of helical flow. The tests in several experimental and field cases show that the enhanced depth-averaged 2-D model can much more reasonably predict the shifting of main flow from inner bank to outer bank, the erosion along outer bank and deposition along inner bank than the depth-averaged 2-D model without considering this effect.

关键词： Secondary flow Channel bends Dispersion Unsteady flow Sediment transport Two- dimensional model Finite volume method

Effect of gland extracts on digging and residing preferences of red imported fire ant workers （Hymenoptera＂ Formicidae）

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Insect Science 2013年第4期20卷 456-466页

作者： Jian Chen Guangmei Zhang USDA-ARS National Biological Control Laboratory Biological Control of Pests Research Unit Stoneville MS 38776 USA

There is evidence that ant-derived chemical stimuli are involved in regulat- ing the digging behavior in Solenopsis invicta Buren. However, the source gland（s） and chemistry of such stimuli have never been revealed. In this study, extracts of mandibular, Dufour＇s, postpharyngeal, and poison glands were evaluated for their effect on ant digging and residing preferences of S. invicta workers from three colonies. In the intracolonial bioassays, workers showed significant digging preferences to mandibular gland extracts in 2 of 3 colonies and significant residing preferences in 1 of 3 colonies; significant digging preferences to Dufour＇s gland extracts in 1 of 3 colonies and significant residing preferences in 2 of 3 colonies. No digging and residing preferences were found for postpharyngeal and poison gland extracts. In intercolonial bioassays, significant digging and residing prefer- ences were found for mandibular gland extracts in 3 of 6 colony combinations. Significant digging preferences to Dufour＇s gland extracts were found in 4 of 6 colony combinations and significant residing preferences in all 6 colony combinations. For postpharyngeal gland extracts, significant digging preferences were found only in 1 of 6 colonial combinations and no significant residing preferences were found. For poison gland extracts, no signif- icant digging preferences were found; significant residing preferences were found in 1 of 6 colony combinations. However, a significant residing deterrence （negative residing preference index） was found for 2 of 6 colony combinations. Statistical analyses using data pooled from all colonies showed that mandibular and Dufour＇s gland extracts caused sig- nificant digging and residing preferences in both intracolonial and intercolonial bioassays but not postpharyngeal and poison gland extracts. By analyzing the data pooled from the same three colonies used for gland extract bioassays, it was found that, in no cases, workers showed significant digging

关键词： digging preference Dufour's gland mandibular gland poison gland,postpharyngeal gland residing preference

Labial tip sensilla of Blissus leucopterus leucopterus （Hemiptera： Blissidae）： Ultrastructure and behavior

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Insect Science 2008年第3期15卷 271-275页

作者： Gerald T. Baker Xiong Chen Peter W.K. Ma Department of Entomology and Plant Pathology Box 9775 Mississippi State University Mississippi State MS 39762 USA

The cuticular sensory receptors that are found on the apex of the labium of hemipterans play an important role in their feeding behavior. In this study we describe the ultrastructure, number, and distribution of sensilla on the labium apex of the chinch bug, Blissus leucopterus leucopterus. Each apical field of sensilla on the labium contains 11 uniporous peg sensilla and one sensillum chaeticum. The uniporous peg sensilla are innervated by 4-5 bipolar neurons that send dendrites in the lumen of each peg. Three neurons are associated with each sensillum chaeticum, two neurons have dendrites in the lumen of the sensillum, and the third dendrite ends in a tubular body at the base of the sensillum. Behavioral tests that involve chemical blockage of the sensory receptors show the importance of the labial sensilla in feeding behavior. Both morphological and behavioral evidence indicate that the labial sensilla have a chemosensitive function.

关键词： behavioral tests chinch bug electron microscopy labial sensilla Nmethylmaleimide

Enhanced UV-B radiation during pupal stage reduce body mass and fat content, while increasing deformities, mortality and cell death in female adults of solitary bee Osmia bicornis

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Insect Science 2015年第4期22卷 512-520页

作者： Oskar Wasielewski Tatiana Wojciechowicz Karol Giejdasz Natraj Krishnan Institute of Zoology Mississippi State University Mississippi State MS 39762 USA Department of Animal Physiology and Biochemistry Poznan University of Life Sciences Poznan Poland Department of Biochemistry Molecular Biology Entomology and Plant Pathology Mississippi State University Mississippi State MS 39762 USA

The effects of enhanced UV-B radiation on the oogenesis and morpho- anatomical characteristics of the European solitary red mason bee Osmia bicornis L. （Hy- menoptera： Megachilidae） were tested under laboratory conditions. Cocooned females in the pupal stage were exposed directly to different doses （0, 9.24, 12.32, and 24.64 kJ/m2/d） of artificial UV-B. Our experiments revealed that enhanced UV-B radiation can reduce body mass and fat body content, cause deformities and increase mortality. Following UV exposure at all 3 different doses, the body mass of bees was all significantly reduced compared to the control, with the highest UV dose causing the largest reduction. Similarly, following UV-B radiation, in treated groups the fat body index decreased and the fat body index was the lowest in the group receiving the highest dose of UV radiation. Mortality and morphological deformities, between untreated and exposed females varied considerably and increased with the dose of UV-B radiation. Morphological deformities were mainly manifested in the wings and mouthparts, and occurred more frequently with an increased dose of UV. Cell death was quantified by the Terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL） assay （DNA fragmentation） during early stages of oogenesis of O. bicornis females. The bees, after UV-B exposure exhibited more germarium ceils with fragmented DNA. The TUNEL test indicated that in germarium, low doses of UV-B poorly induced the cell death during early development. However, exposure to moderate UV-B dose increased programmed cell death. In females treated with the highest dose of UV-B the vast majority of germarium cells were TUNEL-positive.

关键词： Osmia bicornis ovary development radiation TUNEL UV-B

Assessing model parameters sensitivity and uncertainty of streamflow,sediment,and nutrient transport using SWAT

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Information Processing in Agriculture 2019年第1期6卷 61-72页

作者： Abdullah O.Dakhlalla Prem B.Parajuli Department of Agricultural and Biological Engineering Mississippi State UniversityMississippi StateMS 39762United States

The objectives of this study were to(1)simulate streamflow,total sediment(TS),total phosphorus(TP),and total nitrogen(TN)loads;and(2)use the sequential uncertainty fitting(SUFI-2)algorithm to quantify the model parameter sensitivity and uncertainty in simulating streamflow,TS,TP,and TN loads using Soil and Water Assessment(SWAT)model in Big Sunflower River watershed(BSRW).The model was calibrated from 1996 to 2003 and validated from 2004 to 2010 for daily streamflow,TS load,TP load,and TN *** model performed well simulating daily streamflow(R^2=0.58-0.75,NSE=0.47-0.75),TS load(R^2=0.50-0.72,NSE=0.47-0.66),and TP load(R^2=0.79-0.82,NSE=0.73-0.77),and the model performance was slightly low for TN load(R^2=0.13-0.31,NSE=0.09 to 0.07).This study determined that parameter uncertainty was greatest for simulating TN load(p-factor=0.48,r-factor=1.25)and that parameter uncertainty was lowest for simulating streamflow(p-factor=0.70-0.78,r-factor=1.18-1.19).Output uncertainty was much greater during peak streamflow and peak pollutant loads compared to periods of low streamflow and low pollutant *** sensitivity analyses found that streamflow was most sensitive to Manning’s roughness coefficient for the main channel(CH_N2),TS load was most sensitive the peak rate adjustment factor for sediment routing in the tributary channels(ADJ_PKR),TP load was most sensitive to the Phosphorus enrichment ratio for loading with sediments(ERORGP),and TN load was most sensitive to the denitrification exponential rate coefficient(CDN).Uncertainty was found to be much greater during peak streamflow and peak pollutant loads compared to periods of low streamflow and low pollutant loads.

关键词： Model parameters Sensitivity Uncertainty SWAT Pollutant loads

Sediment transport capacity of tidal currents and waves

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Chinese Science Bulletin 1995年第13期40卷 1096-1101页

作者：窦国仁董风舞窦希滨 Nanjing Hydraulic Research Institute Nanjing 210029 China The University of Mississippi MS38677 USA

A lot of estuaries and coastal regions in China are covered with silts and muds, whichare easily suspended and transported under the joint action of tidal currents and windwaves. Therefore, the study on the sediment transport capacity of both tidal currents andwind waves is of theoretical and practical significance. However, because of the extremecomplexity of the problem, the studies in the past were limited to the empirical analyses,and the theoretical exposition was not given yet. In establishing most empirical formulas,the orbital velocity of waves was added to the velocity of the tidal currents in order to ex-

关键词： tidal current wave sediment transport capacity.

Return of investment and profitability analysis of bio-fuels production using a modeling approach

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Information Processing in Agriculture 2016年第2期3卷 92-98页

作者： Yangyang Deng Prem B.Parajuli Department of Agricultural and Biological Engineering Mississippi State UniversityMississippi StateMS 39762United States

The objectives of this study were to evaluate the return of investment and profitability of a bio-gasification facility using a modeling *** on preliminary market analysis,the results determined that the power facilities driven by biomass gasifiers could be profitable if they consider the most sensitive cost factors such as labor,project investment,and feedstock *** result showed that economic feasibility of bio-gasification facility can significantly affect by its production capacity and operating modes(one shift,two shifts,or three shifts).The cost analysis modeling approach developed in this study could be a good approach for economic analysis of bio-syngas and bio-fuel *** addition,this study demonstrated a unique modeling approach to analyze return of investment and profitability of biofuels production.

关键词： Bio-gasification Modeling Sensitivity analysis Profitability analysis

Cost analysis model for catalytic conversion of syngas in to light hydrocarbon gases

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Information Processing in Agriculture 2015年第1期2卷 37-50页

作者： Yangyang Deng Prem B.Parajuli Hakkwan Kim Department of Agricultural and Biological Engineering Mississippi State UniversityMississippi StateMS 39762United States

Bio-gasification is a new technology and considered as a more efficient way to utilize *** economic feasibility becomes one of the greatest issues when we apply this new *** of economic feasibility of a bio-gasification facility needs better understanding of its production unit cost under different capacities and different working shift *** objective of this study was to evaluate the unit cost of biofuel products(Liquid HCs,Light HCs and Oxygenates CxHyOz)under different capacities using a modeling *** cost analysis model was developed using Visual Basic Microsoft 2008,computer programming language and mathematical *** modeling results showed that the unit costs of biofuel product from bio-gasification facility were significantly affected by production capacities of *** the facility capacity increased from 65 to 10,000 N m^3 h^-1,the biofuel production unit cost of gas(Light HCs),oil(Liquid HCs),and aqueous(Oxygenates CxHyOz)decreased from$38.92 per MMBTU,$30.89 per gallon and$25.74 per gallon to$2.01 per MMBTU,$1.59 per gallon,and$1.33 per gallon,*** results of the sensitivity analysis showed that feedstock cost was the most sensitive cost factor on unit costs for all biofuel products at high *** cost analysis model developed in this study could be used to optimize production unit costs of bio-fuel products from bio-gasification facility.

关键词： Biofuel Bio-gasification Cost analysis model Production capacity Unit cost