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SEDImENT DAmAGES AND RECENT TRENDSIN THE UNITED STATES

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International Journal of Sediment Research 2000年第2期15卷 135-148页

作者： jerry m. Bernard (National Geologist) Thomas A. Iivari(Senior Hydrologist, United States Department of Agriculture-Natura ResourcesConservation Service, Washington, DC) United States Dept. of Agriculture Nat. Resources Conservation Service Washington DC United States

In the United States, cropland erosion has decreased by an estimated one billion tons or 42 Percent for the period 1982 to 1997 (USDA NRCS, 1998) through erosion reduction provisions of the Food Security Actof 1985 and the ongoing soil conservation programs administered by the United States Department ofAgriculture’s Soil Conservation Service (USDA-SCS), which became the Natural Resources ConservationService (USDA-NRCS) in *** U.S. Geological Survey has measured suspended sediment loads at strearn gages from 198O through1989 and showed primarily decreases of from 1 to 12 percent for most regions and increases for only threeregions, ranging from 2 to l2 percent.A Reservoir Sediment Information System (RESIS) was created so that decades of dare on reservoir sediment deposits could be evaluated (Atwood, 1994, Steffen, 1994; Atwood and Steffen, 1994). Theresults of analyses show a major increase in unit-area sediment deposition rates during the period 1970through 1985, which may be attributable to increased cropland acreage, a switch from diversified farming tointensive monocultUred crops, with widespread adoption of soybeans. The most recent measured ratesshow that 25 percent of the United States reservoirs would be at least half-filled with sediment by 2O18,although there is a significant data gap since 1985. Relatively few reservoirs were surveyed since 1985 dueto lack of funding priority and increased survey labor costs.

关键词： Cropland erosion Soil conservation program Suspended sediment Reservoir sediment information system

methanol oxidation over shell-core mOx/Fe2O3（m = mo, V, Nb） catalysts

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Chinese Journal of Catalysis 2019年第11期40卷 1686-1692页

作者： Pip Hellier Peter P. wells michael Bowker UK Catalysis Hub Research Complex at Harwell Rutherford Appleton Laboratory Harwell UK School of Chemistry Cardiff University Cardiff UK School of Chemistry University of Southampton Southampton UK Diamond Light Source Ltd Harwell Science and Innovation Campus Didcot UK

We present a comparison of mo, V and Nb oxides as shell materials atop haematite cores used for selective methanol oxidation. While mo and V both yield high selectivity to formaldehyde, Nb does not. Very different reactivity patterns are seen for Nb, which mainly shows dehydrogenation (to CO) and dehydration (to DmE), indicating the lack of a complete shell, while Raman spectroscopy shows that the mo and V formation process is not followed by NbOx. We suggest this is due to the large differences in mobility within the solid materials during formation, NbOx requiring significantly higher (and deleterious) calcination temperatures to allow sufficient mobility for shell completion.

关键词： methanol Oxidation Formaldehyde Iron molybdate Shell-core catalyst

DPm dispersion inside a single straight entry using dynamic mesh model

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International Journal of Coal Science & Technology 2017年第3期4卷 234-244页

作者： Yi Zheng Ying Li magesh Thiruvengadam Hai Lan jerry C. Tien missouri University of Science and Technology Rolla MOUSA Clean Air Power Inc. Poway CA 92064 USA monash University Clayton Campus Wellington RoadClayton VIC 3800 Australia

Three-dimensional simulations of diesel particulate matter （DPm） distribution inside a single straight entry for the Load-Haul-Dump loader （LHD）-truck loading and truck hauling operations were conducted by using ANSYS FLUENT computational fluid dynamics software. The loading operation was performed for a fixed period of 3 min. The dynamic mesh technique in FLUENT was used to study the impact of truck motion on DPm distribution. The resultant DPm distributions are presented for the cases when the truck were driving upstream and downstream of the loading face. Interesting phenomena were revealed in the study including the piston effect, layering of DPm in the roof region, and backflow of diesel exhaust against ventilation. The results from the simulation can be used to determine if the areas inside the face area and straight entry exceed the current U.S. regulatory requirement for DPm concentration （〉160 pg/m3）. This research can guide the selection of DPm reduction strategies and improve the working practices for the underground miners.

关键词： CFD · DPm · Dynamic meshing ·Piston effect · Backflow · Buoyancy effect · Layering of DPm

Hydrocarbon indication in Rio Bonito Formation sandstone:Implication for CO_(2)storage in São Paulo,Brazil

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Energy Geoscience 2024年第1期5卷 331-341页

作者： Richardson m.Abraham-A Haline V.Rocha Saulo B.de Oliveira Colombo C.G.Tassinarri Orlando C.da Silva Institute of Energy and Environment University of São PauloSão PauloBrazil Research Centre for Greenhouse Gas Innovation University of São PauloSão PauloBrazil

São Paulo State has witnessed CO_(2)storage-based investigations considering the availability of suitable geologic structures and proximity to primary CO_(2)source sinks related to bioenergy and carbon capture and storage(BECCS)*** current study presents the hydrocarbon viability evaluations and CO_(2)storage prospects,focusing on the sandstone units of the Rio Bonito *** objective is to apply petrophysical evaluations with geochemical inputs in predicting future hydrocarbon(gas)production to boost CO_(2)storage within the study *** study used data from eleven wells with associated wireline logs(gamma ray,resistivity,density,neutron,and sonic)to predict potential hydrocarbon accumulation and fluid mobility in the investigated *** samples(shale and carbonate)obtained from depths>200 m within the study location have shown bitumen *** geochemistry data of the Rio Bonito Formation shale beds suggest they are potential hydrocarbon source rocks and could have contributed to the gas accumulations within the sandstone *** drilled well data,e.g.,CB-1-SP and TI-1-SP,show hydrocarbon(gas)presence based on the typical resistivity and the combined neutron-density responses at depths up to 3400 m,indicating the possibility of other hydrocarbon members apart from the heavy oil(bitumen)observed from the near-surface rocks *** the three-dimensional(3-D)model,the free fluid indicator(FFI)is more significant towards the southwest and southeast of the area with deeper depths of occurrence,indicating portions with reasonable hydrocarbon recovery rates and good prospects for CO_(2)injection,circulation and permanent ***,future studies based on contemporary datasets are required to establish the hydrocarbon viability further,foster gas production events,and enhance CO_(2)storage possibilities within the region.

关键词： ParanáBasin Hydrocarbon indication Sandstone reservoirs Rio Bonito Formation CO_(2)storage Hydrocarbon recovery factor Fluid injection rate

Elevated Carbon Dioxide and Soil moisture on Early Growth Response of Soybean

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Agricultural Sciences 2015年第2期6卷 263-278页

作者： m. madhu jerry L. Hatfield Indian Institute of Soil and Water Conservation (IISWC) Research Centre Koraput India National Laboratory for Agriculture and the Environment (NLAE) Ames USA

Interactions between elevated [CO2] and soil water availability have the potential impact on crops and future food security of the world. The study was conducted to investigate vegetative growth response of soybeans under two [CO2] (380 and 800 μmol mol-1) with three soil moisture levels in controlled environment. Slow growth rate and altered crop phenology of soybeans were observed under elevated [CO2] at early stage (V-3/V-4), but showed positive physiologically response at later stage (R3) indicating adoptive mechanism of plants to high [CO2]. Elevated [CO2] decreases the number of leaves by 23% and 14% and reduces in leaf areas by 11.7% and 9.7% compared with ambient [CO2] at 29 and 44 days after planting (DAP), respectively. Adaptive mechanism of plants to high [CO2] produced 39% and 83.7% greater leaf number and leaf areas, respectively at later stage (R3) of the crop growth (59 DAP). There was a reduction in a specific leaf area (SLA) at 29 DAP (22.2%) but an increase at 44 DAP (1.4%) and 58 DAP (8.5%) under elevated [CO2]. Dry matter production of plants was increased significantly for elevated [CO2]. Increase in leaf C (mal soil moisture condition produced a maximum number of pods (54.8% - 122.4%) and an increase in dry weight of pods (29.8% - 56.6%). Plants under elevated [CO2] produced significantly greater numbers of root nodules per plant by 114% compared with plants under ambient [CO2] at 44 DAP. These results show a direct and interactive effect of elevated [CO2] and soil moisture on plant growth that will affect not only the global food security but also nutritional security.

关键词： Elevated Carbon Dioxide Dry matter Interaction Effect Growth Response Phenology Root Nodules Soil moisture

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土壤阻力连续测试设备研制

农业工程学报 2009年第2期25卷 67-71页

作者：赵新罗锡文 L.G.wells 华南农业大学南方农业机械与装备关键技术省部共建教育部重点实验室广州510642 美国肯塔基大学生物与农业工程系列克星敦40546

为解决目前点采样方法获取的土壤压实信息少和信息获取速度慢的不足,该文研制了可快速连续测量土壤阻力(水平方向)以反映土壤压实程度的测试系统。系统包括机械部分、传感器和信息采集3部分。测试系统由拖拉机牵引,工作时连续测试速度1 ... 详细信息

为解决目前点采样方法获取的土壤压实信息少和信息获取速度慢的不足,该文研制了可快速连续测量土壤阻力(水平方向)以反映土壤压实程度的测试系统。系统包括机械部分、传感器和信息采集3部分。测试系统由拖拉机牵引,工作时连续测试速度1 m/s,土壤阻力信息采样频率为300 Hz,采样数据处理后与GPS定位数据对应存储。实验室试验表明,系统平均测试精度达93.4%。田间试验显示,测试系统性能可靠稳定,具有连续快速获取土壤压实程度信息并反映土壤压实程度空间分布的能力。定义的土壤阻力指数TRI可以反映土壤的压实程度。

关键词：八角环传感器变深耕作土壤阻力土壤压实

The genetic basis of grape and wine aroma

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Horticulture Research 2019年第1期6卷 716-739页

作者： jerry Lin mélanie massonnet Dario Cantu Department of Viticulture and Enology University of California DavisOne Shields AveDavisCA 95616USA

The grape is one of the oldest and most important horticultural *** and wine aroma has long been of cultural and scientific *** diverse compound classes comprising aroma result from multiple biosynthetic *** fairly recently have researchers begun to elucidate the genetic mechanisms behind the biosynthesis and metabolism of grape volatile *** review summarizes current findings regarding the genetic bases of grape and wine aroma with an aim towards highlighting areas in need of further *** the literature,we compiled a list of functionally characterized genes involved in berry aroma biosynthesis and present them with their corresponding annotation in the grape reference genome.

关键词： Grape aroma metabolism

Impact of grazing on germination trait selection in an alpine grassland on the Tibet Plateau

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Journal of Plant Ecology 2022年第4期15卷 818-828页

作者： Yang Liu Kun Liu Zhilong Zhang Shiting Zhang Carol C.Baskin jerry m.Baskin Ting Liang Haiyan Bu Shuxia Li Tingting Zhang Xianliang Cui Sa Xiao State Key Laboratory of Grassland and Agro-ecosystems School of Life SciencesLanzhou UniversityLanzhou 730020China Department of Chemistry and Life Science Gansu Normal College for NationalitiesHezuo 74700China Department of Biology University of KentuckyLexingtonKY 40506USA Department of Plant and Soil Sciences University of KentuckyLexingtonKY 40506USA

Previous studies indicated that grazing can cause significant changes in abiotic and biotic environment in ***,how these changes impact germination trait selection in grassland has not been well ***,we aimed to explore whether grazing can significantly change germination trait diversity and composition of grasslands *** measured the germination traits of species in the laboratory,and compared their performance in grazed and nongrazed ***,we compared the community-weighted means of germination traits and functional diversity of grazed and nongrazed grasslands based on these germination traits to know whether grazed and nongrazed grasslands differed in their germination trait *** the species level,we found that the changes of abundance in grazed and nongrazed grasslands were not related to species’germination ***,at the community level,compared with nongrazed grasslands,species in the grazed grasslands generally exhibited a higher seed germination ***,seed germination response in grazed grasslands was more positively related to alternating temperature than in nongrazed grasslands,and breadth of the germination temperature niche was narrower in grazed than in nongrazed *** with nongrazed grasslands,seed germination trait diversity was increased and germination trait evenness decreased in grazed *** can change microhabitat conditions,thereby changing germination trait selection by environmental filtering,resulting in a significant difference in germinate trait composition at the community level.

关键词： alpine grassland biodiversity germination trait selection grazing Tibet Plateau

DPm dissipation experiment at mST＇s experimental mine and comparison with CFD simulation

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Journal of Coal Science & Engineering(China) 2011年第3期17卷 285-289页

作者： ZHENG Yi LAN Hai THIRUVENGADAm magesh TIEN jerry C Department of mining ＆ Nuclear Engineering Missouri University of Science and Technology （MST） Rolla MO 65401 USA

Diesel Particulate matter （DPm） is regulated in the U.S. for both underground coal and metal/nonmetal mines. Today, many underground mines still face difficulty in compliance with DPm regulations. The DPm research carried out in missouri University of Science and Technology （mST） is to use computational fluid dynamics （CFD） to study the DPm distribution in commonly used face areas. The result is expected to be used for selection of DPm reduction strategies and better working practices, which can help the underground mines to meet regulation limits and improve the working environment for the miners. An experiment was conducted at mST＇s Experimental mine to validate CFD simulation. DPm was collected at four locations downstream of a stationary diesel engine. The experiment data were then compared with the CFD simulation results. The comparison shows that CFD simulation can forecast the location of DPm concentration with practical accuracy （less than 0.15 m）. CFD can be used to further study DPm distribution in commonly used working faces and give guidance to DPm reduction.

关键词： DPm DPm dissipation CFD validation study