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Urease activity and nitrogen dynamics in highly weathered soils with designer biochars under corn cultivation

Biochar 2020年第3期2卷 343-356页

作者： Gilbert C.Sigua Jeff M.Novak don w.watts william T.Myers Thomas F.Ducey Kenneth C.Stone United States Department of Agriculture Agricultural Research ServiceCoastal Plains SoilWaterand Plant Research Center2611 West Lucas StreetFlorenceSC 29501USA

The application of designer biochar has the potential to impact soil enzyme activity and soil nitrogen ***,very little is known about the mechanisms responsible for biochar-enzyme-nitrogen interaction in highly weathered *** objective of our 3-year(2016-2018)field experiment was to evaluate the effectiveness of designer biochars(DB)in enhancing urease activity(UA),total nitrogen(TN),total inorganic nitrogen(TIN),and nitrogen uptake(NU)at different growth stages(GS)of corn in a highly weathered soil of southeastern Coastal Plain region,*** treatments have consisted of the control,100%pine chips(100PC),100%poultry litter(100PL),2:1 blend of PC and PL(PCPL),100%raw switchgrass(Panicum vaginatum,L;100RSG),and 2:1 blend of PC and RSG(PCRSG).All the designer biochar treatments were applied at the rate of 30,000 kg ha^(−1)to a Goldsboro loamy sand in *** activity,TN,TIN,and NU varied remarkably with DB(p≤0.0001)at different GS(p≤0.0001)of *** treated with 100PL had the greatest UA(28.18μg N g^(−1)h^(−1)),TN(0.087%),and TIN(14.53 mg kg^(−1))while the least UA,TN,and TIN of 20.55μg N g^(−1)h^(−1),0.063%,and 5.42 mg kg^(−1),respectively,were observed from the *** three-year TN average increase over the control was in the order:100PL(36.8%)>100RSG(25.8%)>PCRSG(25.3%)>PCPL(23.9%)>100PC(7.1%).The greatest NU of corn of 140.4 kg N ha^(−1)was from soils treated with 100PL while the least amount of NU was from ***,our results showed promising significance for the treatment of highly weathered soils since the application of DB did enhance UA and improve TN and TIN in the soils.

关键词： Goldsboro sandy loam Coastal plain Corn Urease activity Highly weathered soil Nitrogen Designer biochars Total inorganic nitrogen

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Seismic Reflection Characteristics of Naturally-Induced Subsidence Affecting Transportation

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Journal of China University of Geosciences 2009年第3期20卷 496-512页

作者： Richard D Miller Jianghai Xia don w Steeples Kansas Geological Survey The University of Kansas Lawrence KS 66047 USA Department of Geology The University of Kansas Lawrence KS 66047 USA

High-resolution seismic reflections have been used effectively to investigate sinkholes formed from the dissolution of a bedded salt unit found throughout most of Central Kansas. Surface subsidence can have devastating effects on transportation structures. Roads, rails, bridges, and pipelines can even be dramatically affected by minor ground instability. Areas susceptible to surface subsidence can put public safety at risk. Subsurface expressions significantly larger than surface depressions are consistently observed on seismic images recorded over sinkholes in Kansas. Until subsidence reaches the ground surface, failure appears to be controlled by compressional forces evidenced by faults with reverse orientation. Once a surface depression forms or dissolution of the salt slows or stops, subsidence structures are consistent with a tensional stress environment with prevalent normal faults. Detecting areas of rapid subsidence potential, prior to surface failure, is the ultimate goal of any geotechnical survey where the ground surface is susceptible to settling. Seismic reflection images have helped correlate active subsidence to dormant paleofeatures, project horizontal growth of active sinkholes based on subsurface structures, and appraise the risk of catastrophic failure.

关键词： shallow seismic reflection imaging subsidence sinkhole.

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Classifying forest inventory data into species-based forest community types at broad extents： exploring tradeoffs among supervised and unsupervised approaches

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Forest Ecosystems 2018年第1期5卷 91-107页

作者： jennifer k.costanza don faber-langendoen john w.coulston david n.wear Department of Forestry and Environmental Resources North C arolina State University3041 Cornwalis RdResearch Triangle ParkRaleighNC 27709USA NatureServe 4600 N.Fairfax Dr7th FloorArlingtonVA 22203USA Southern Research Station USDA Forest ServiceBlacksburgVAUSA Southern Research Station USDA Forest ServiceRaleighNCUSA

Background： Knowledge of the different kinds of tree communities that currently exist can provide a baseline for assessing the ecological attributes of forests and monitoring future changes. Forest inventory data can facilitate the development of this baseline knowledge across broad extents, but they first must be classified into forest community types. Here, we compared three alternative classifications across the United States using data from over 117,000 U.S. Department of Agriculture Forest Service Forest Inventory and Analysis （FIA） plots. Methods： Each plot had three forest community type labels：（1）＂FIA＂ types were assigned by the FIA program using a supervised method; （2）＂USNVC＂ types were assigned via a key based on the U.S. National Vegetation Classification; （3）＂empirical＂ types resulted from unsupervised clustering of tree species information. we assessed the degree to which analog classes occurred among classifications, compared indicator species values, and used random forest models to determine how well the classifications could be predicted using environmental variables. Results： The classifications generated groups of classes that had broadly similar distributions, but often there was no one-to-one analog across the classifications. The Iongleaf pine forest community type stood out as the exception： it was the only class with strong analogs across all classifications. Analogs were most lacking for forest community types with species that occurred across a range of geographic and environmental conditions, such as Ioblolly pine types, indicator species metrics were generally high for the USNVC, suggesting that LJSNVC classes are floristically well-defined. The empirical classification was best predicted by environmental variables. The most important predictors differed slightly but were broadly similar across all classifications, and included slope, amount of forest in the surrounding landscape, average minimum temperature, and other climate variab

关键词： Big data Correspondence analysis Dominant species Forest communities Global change,Hierarchical classification Indicator species Random forests Species assemblages

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The significance of midsummer movements of Autographa gamma： Implications for a mechanistic understanding of orientation behavior in a migrant moth

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Current Zoology 2013年第3期59卷 360-370页

作者： Jason w. CHAPMAN Ka S. LIM don R. REYNOldS Department ofAgroEcology Rothamsted Research Harpenden Hertfordshire AL5 2JQ UK Environment and Sustainability Institute University of Exeter Penryn Cornwall TR10 9EZ UK Natural Resources Institute University of Greenwich Chatham Kent ME4 4TB UK

The silver Y moth Autographa gamma undertakes windbome spring and fall migrations between winter breeding re- gions around the Mediterranean and summer breeding regions in northern Europe. Flight behaviors facilitating these migrations include：（i） selection of seasonally-favorable tailwinds; （ii） flying at the altitude of the fastest winds; （iii） adopting flight headings that partially counteract crosswind drift; and （iv） seasonal reversal of preferred directions between spring and fall. In the UK, ra- dar measurements indicate that migratory activity is pronounced during the spring and fall, but is usually very low during mid- summer （July）. However, an atypically intense period of high-altitude flight was recorded during July 2006, and in this study we compare the flight behavior of A. gamma during these midsummer movements with the more typical spring and fall migrations. During July 2006, activity was most intense at significantly lower altitudes than occurred in spring or fall, and was not associated with the height of the fastest winds; consequently displacement speeds were significantly slower. The most striking difference was an absence of tailwind selectivity in July with windborne movements occurring on almost every night of the month and on tailwinds from all directions. Finally, orientation behavior was quantitatively different during July, with significantly greater dis- persion of flight headings and displacements than observed in spring and fall. we discuss mechanisms which could have caused these differences, and conclude that a lack of appropriate photopcriod cues during development of the summer generation resulted in randomly-oriented ＇dispersive＇ movements that were strikingly different from typical seasonal migrations .

关键词： Long-range migration Dispersal High-altitude flight Photoperiod Entomological radar Noctuid moths

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Innovative confocal laser method for exact dioptric power measurement of intraocular lens implants Invited Paper

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Chinese Optics Letters 2008年第12期6卷 876-878页

作者： Ilko K.Ilev Robert w.Faaland Do-Hyun Kim Robert H.James don Calogero Office of Science and Engineering Laboratories Center for Devices and Radiological Health U.S.Food and Drug Administration10903 New Hampshire AvenueSilver Spring Office of Device Evaluation Center for Devices and Radiological Health U.S.Food and Drug Administration9200 Corporate BoulevardRockville

we present a novel confocal laser method （CLM） for precise testing of the dioptric power of both positive and negative intraocular lens （IOL） implants. The CLM principle is based on a simple fiber-optic confocal laser design including a single-mode fiber coupler that serves simultaneously as a point light source used for formation of a collimated Gaussian laser beam, and as a highly sensitive confocal point receiver. The CLM approach provides an accurate, repeatable, objective, and fast method for IOL dioptric power measurement over the range from 0 D to greater than ±30 D under both dry and in-situ simulated conditions.

关键词： Crystalline lens Fiber optic couplers Gaussian beams Intraocular lenses Laser beams Single mode fibers

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Editorial for the Special Issue on Switched-Capacitor Circuits and Partial Processing Techniques

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Chinese Journal of Electrical Engineering 2020年第4期6卷 1-2页

作者： don Tan Yan-Fei Liu Xinbo Ruan IEEE

Switched-capacitor circuits are gaining renewed interests for its capability of processing unregulated power with 99% duty ratio,ultra-high efficiency and ultra-high power *** various techniques,half-resonance circuit... 详细信息

关键词： power Switched circuits

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A NOVEL EOR POLYMER (Ⅱ)——INVESTIGATION ON IN-SITU GELATION OF SMRF SYSTEM IN BEREA CORE

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Chinese Journal of Polymer Science 1995年第1期13卷 66-73页

作者：庄银凤 Stanley McCool G.Paul willhite don w.Green Department of Material Engineering Zhengzhou UniversityZhengzhou 450052 China The Tertiary Oil Recovery Project The University of Kansas Lawrence KS 66045U. S. A.

In-situ gelation of aqueous sulfomethylated resorcinol formaldehyde (SMRF) system inBerea core has been investigated. Two sets of displacement experiments were conducted with thissystem (containing 5% NaCl, 0. 036% CaCl_2. 2H_2O). The brine permeabilities of the coreswere reduced significantly from about 600 to 0.1 md. The in-situ gelation in Berea core occurreda little bit earlier than gelation anticipated from bulk test in the experiments. The gel time waseasier to control at initial pH between 6 and 8. During injection of SMRF system, the apparentviscosity was less than 1 mPa·s at 41℃.

关键词： In-situ gelation EOR polymer Oil recovery Sulfomethylated resorcinol formaldehyde

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A NOVEL EOR POLYMER (Ⅰ)—STUDY ON GELATION OF RESORCINOL-FORMAldEHYDE SYSTEMS

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Chinese Journal of Polymer Science 1995年第1期13卷 59-65页

作者：庄银凤 Stanley McCool G.Paul willhite don w.Green Department of Material Engineering Zhengzhou UniversityZhengzhou 450052China The Tertiary Oil Recovery Project The University of Kansas Lawrence KS 66045U. S. A.

Factors affecting the gelation of resorcinol-formaldehyde systems have been examined overvariable ranges applicable to oilfield use. Gelation of resorcinol-formaldehyde (RF) system wassensitive to pH,salinity and hardness. Generally,this gel system could be used in fresh water orlow salinity brine at pH higher than about 9. The application would require careful monitoring ofinjection fluids to avoid premature gelation or prolonged shut-in times,especially under conditionsof low salinity and high pH. Salinity and hardness compatibilities of the system were improved bysulfomethylation of resorcinol. Aqueous sulfomethylated resorcinol formaldehyde (SMRF)system could be used in brine with higher salinity and hardness and at a wider pH range of 5--10.

关键词： Gelation Resorcinol formaldehyde Oil recovery EOR polymer

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Fifth-Order A-wENO Schemes Based on the Adaptive Diffusion Central-Upwind Rankine-Hugoniot Fluxes

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Communications on Applied Mathematics and Computation 2023年第1期5卷 295-314页

作者： Bao-Shan wang wai Sun don Alexander Kurganov Yongle Liu School of Mathematical Sciences Ocean University of ChinaQingdao 266100ShandongChina Department of Mathematics SUSTech International Center for Mathematics and Guangdong Provincial Key Laboratory of Computational Science and Material DesignSouthern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Mathematics Harbin Institute of TechnologyHarbin 150001HeilongjiangChina Department of Mathematics Southern University of Science and TechnologyShenzhen 518055GuangdongChina

we construct new fifth-order alternative wENO(A-wENO)schemes for the Euler equations of gas *** new scheme is based on a new adaptive diffusion centralupwind Rankine-Hugoniot(CURH)numerical *** CURH numerical fluxes have been recently proposed in[Garg et al.J Comput Phys 428,2021]in the context of secondorder semi-discrete finite-volume *** proposed adaptive diffusion CURH flux contains a smaller amount of numerical dissipation compared with the adaptive diffusion central numerical flux,which was also developed with the help of the discrete RankineHugoniot conditions and used in the fifth-order A-wENO scheme recently introduced in[wang et *** J Sci Comput 42,2020].As in that work,we here use the fifth-order characteristic-wise wENO-Z interpolations to evaluate the fifth-order point values required by the numerical *** resulting one-and two-dimensional schemes are tested on a number of numerical examples,which clearly demonstrate that the new schemes outperform the existing fifth-order A-wENO schemes without compromising the robustness.

关键词： A-wENO schemes Central-upwind schemes Discrete Rankine-Hugoniot conditions Numerical dissipation switch Local speeds of propagation Euler equations of gas dynamics

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Source model of the 11th July 2004 Zhongba earthquake revealed from the joint inversion of InSAR and seismological data

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Earthquake Science 2011年第2期24卷 207-220页

作者： Shengji wei Sidao Ni Xianjie Zha don Helmberger Seismological Laboratory of California Institute of Technology Pasadena CA 91125 USA Key Laboratory of Dynamical Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Mengcheng National Geophysical Observatory Department of Earth and Space Science University of Science and Technology of China Hefei 230026 China

we use interferometric synthetic aperture radar （InSAR） and broadband seismic waveform data to estimate a source model of the 11th July, 2004 M w 6.2 Zhongba earthquake, Tibet of China. This event occurred within the seismically active zone of southwestern Tibetan Plateau where the east-west extension of the upper crust is observed. Because of limitations in one pair of InSAR data available, there are trade-offs among centroid depth, rupture area and amount of slip. Available seismic data tightly constrain the focal mechanism and centroid depth of the earthquake but not the horizontal location. Together, two complementary data sets can be used to identify the actual fault plane, better constrain the slip model and event location. we first use regional seismic waveform to estimate point source mechanism, then InSAR data is used to obtain better location. Finally, a joint inversion of teleseismic P-waves and InSAR data is performed to obtain a distributed model. Our preferred point source mechanism indicates a seismic moment of ～2.2×10 18 N·m （～M w 6.2）, a fault plane solution of 171° （342 ° ）/42 ° （48 ° ）/-83 ° （-97 ° ）, corresponding to strike/dip/rake, and a depth of 11 km. The fault plane with strike of 171 ？ and dip of 42° is identified as the ruptured fault with the aid of InSAR data. The preferred source model features compact area of slips between depth of 5–11 km and 10 km along strike with maximum slip amplitude of about 1.5 m.

关键词： finite fault InSAR joint inversion Zhongba earthquake

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