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Variations of CO2 Mixing Ratios in the Air near the Ground in the European Territory of Russia

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Journal of Environmental Science and Engineering(A) 2013年第9期2卷 531-536页

作者： Felix Kashin State Budgetary Institution research and production association "typhoon " Obninsk 249038 Russia

The instrumentation, method and measurement results used for measurements of CO2 concentrations in surface air of Obninsk （55.1° N, 36.9° E, 183 m above the sea level） located at a distance of 105 km to the south-west of Moscow are presented. Proposed is a method of experimental data filtering allowing one to separate natural and anthropogenic variations of CO2 concentrations. It is shown that minimal concentrations of CO2 registered in Obninsk and at the continental stations of GAW WMO characterize not only the ＂regional background＂ but also coincide with the data from GAW WMO background stations located in the oceanic regions. In this connection, one can assume that the excess in measured CO2 concentration over its minimal values, making about 5-6 ppm, is connected with an anthropogenic emission, and the continent should be considered as an anthropogenic source of C02.

关键词： Carbon dioxide mixing ratio natural and anthropogenic variations.

A Comparison of Two Bulk Microphysics Parameterizations for the Study of Aerosol Impacts on an Idealized Supercell

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Advances in Atmospheric Sciences 2022年第1期39卷 97-116页

作者： Wanchen WU Wei HUANG Baode CHEN Shanghai typhoon Institute and Key Laboratory of Numerical Modeling for Tropical Cyclone of China Meteorological AdministrationShanghai 200030China

Idealized supercell storms are simulated with two aerosol-aware bulk microphysics schemes(BMSs),the Thompson and the Chen-Liu-Reisner(CLR),using the Weather research and Forecast(WRF)*** objective of this study is to investigate the parameterizations of aerosol effects on cloud and precipitation characteristics and assess the necessity of introducing aerosols into a weather prediction model at fine grid *** results show that aerosols play a decisive role in the composition of clouds in terms of the mixing ratios and number concentrations of liquid and ice hydrometeors in an intense supercell *** storm consists of a large amount of cloud water and snow in the polluted environment,but a large amount of rainwater and graupel instead in the clean *** total precipitation and rain intensity are suppressed in the CLR scheme more than in the Thompson scheme in the first three hours of storm *** critical processes explaining the differences are the auto-conversion rate in the warm-rain process at the beginning of storm intensification and the low-level cooling induced by large ice *** cloud condensation nuclei(CCN)activation and auto-conversion processes of the two schemes exhibit considerable differences,indicating the inherent uncertainty of the parameterized aerosol effects among different *** the aerosol effects,the fall speed characteristics of graupel in the two schemes play an important role in the storm dynamics and precipitation via low-level *** rapid intensification of storms simulated with the Thompson scheme is attributed to the production of hail-like graupel.

关键词： numerical weather prediction aerosol particle size distribution aerosol-aware microphysics scheme supercell precipitation intensity precipitation physics

Effects of supplementation of Brachiaria brizantha cv. Piatá and Napier grass with Desmodium distortum on feed intake,digesta kinetics and milk production in crossbred dairy cows

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Animal Nutrition 2018年第2期4卷 222-227页

作者： Mupenzi Mutimura Cyprian Ebong Idupulapati M.Rao Ignatius V.Nsahlai Rwanda Agriculture Board Department of Animal Production association for Strengthening Agricultural research in Eastern and Central Africa International Centre for Tropical Agriculture United States Department of Agriculture Agricultural Research ServicePlant Polymer Research UnitNational Center for Agricultural Utilization Research University of Kwa Zulu-Natal School of AgriculturalEarth and Environmental SciencesDepartment of Animal Science and Poultry SciencePietermaritzburg Campus

This study was planned to analyse the basis that make Brachiaria species with greater feeding value than Napier grass(Pennisetum purpureum) for lactating dairy *** lactating crossbred cows were stallfed on Brachiaria brizantha *** or Napier grass *** Cameroon supplemented(mixed on fresh matter basis) or unsupplemented with Desmodium distortum, a forage *** cows were fed on fresh matter basis under small-holder farming *** showed that *** *** had higher contents of dry matter(DM), crude protein(CP) and organic matter(OM), but lower contents of neutral detergent fibre(NDF) and acid detergent fibre(ADF) than Napier grass(P < 0.001).The legume supplementation increased intakes of CP and metabolizable energy(ME; P < 0.001), with higher effect on cows fed *** *** than on cows fed Napier *** daily milk yield was lower on diets based on Napier grass than those based on *** ***(P < 0.001).The retention time of the particle phase of digesta in the digestive tract was longer on Napier grass(83.1 h) than on *** ***(62.8 h)(P < 0.05).It was concluded that in dairy cows, legume supplementation of *** *** increases nutrient intake, hence resulting in higher milk yields than supplementation of Napier grass.

关键词： Brachiaria grass Tropical grasses Napier grass Nutrient intake Legume supplementation Retention time

Rumen liquor from slaughtered cattle as inoculum for feed evaluation

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Animal Nutrition 2017年第3期3卷 300-308页

作者： Pius Lutakome Fred Kabi Francis Tibayungwa Germana H.Laswai Abiliza Kimambo Cyprian Ebong World Agroforestry Centre(ICRAF) Uganda Country Office Department of Agricultural production School of Agricultural SciencesCollege of Agricultural and Environmental Sciences Makerere University Department of Animal Aquaculture and Range SciencesSokoine University of Agriculture association for Strengthening Agricultural research in East and Central Africa(ASARECA) Secretariat

Use of nonlinear mathematical models has been majorly based on in vitro gas production(GP) data generated when substrates are incubated with rumen liquor from fistulated steers. However,existing evidence suggests that rumen liquor from slaughtered cattle of unknown dietary history also generates quantifiable in vitro GP data. Fitting and description of GP data obtained from 4 diets incubated with rumen liquor from slaughtered cattle was evaluated using single-pool exponential model with discrete lag time(EXPL), logistic(LOG), Groot's(GRTS) and Gompertz(GOMP) models. Diets were formulated by varying proportions of Rhodes grass(Chloris gayana) hay and a concentrate mixed on dry matter basis to be: 1,000 g/kg Rhodes grass hay(RGH) and 0 of the concentrate(D1), 900 g/kg RGH and 100 g/kg concentrate(D2), 800 g/kg RGH and 200 g/kg concentrate(D3), 700 g/kg RGH and 300 g/kg concentrate(D4). Dietary kinetics for the models were determined by measuring GP at 2,4.8,10.18,24.36,48.72,96 and 120 h. Model comparison was based on derived GP kinetics, graphical analysis of observed versus predicted GP profiles plus residual distribution and goodness-of-fit from analysis of root mean square error(RMSE), adjusted coefficient of determination(Adj-R^2) and Akaike's information criterion(AIC). Asymptotic GP, half-life and fractional rate of GP differed(P < 0.001) among the 4 models. The RMSE, Adj-R^2 and AIC ranged from 1.555 to 4.429,0.906 to0.984 and 2.452 to 15.874, respectively, forall diets compared across the 4 models. Based on the goodness-of-fit statistical criterion, GP profiles of D1 were more appropriately fitted and described by GRTS and GOMP than the EXPLand LOG models. The GRTS model had the lowest AIC value for D2(2.452). Although GRTS model had the most homogenous residual dispersion for the 4 diets, all the 4 models exhibited a sigmoidal ***, rumen liquor from slaughtered cattle of unknown dietary history can be used to derive nutritionally important fee

关键词： In vitro gas production technique Model comparison Model selection Nonlinear mathematical models Rhodes grass hay Rumen liquor

Selective removal of heavy metals by Zr-based MOFs in wastewater: New acid and amino functionalization strategy

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Journal of Environmental Sciences 2023年第2期124卷 268-280页

作者： Ping Chen Yalan Wang Xiaoqin Zhuang Haijin Liu Guoguang Liu Wenying Lv College of Environmental Science and Engineering and Institute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou association of Circular Economy and Cleaner production Guangzhou 510006China College of Environment Henan Normal UniversityXinxiang 453007China

Zr-based metal-organic frameworks(MOFs)have been developed in recent years to treat heavy metals,*** chromium Cr^(6+)pollution,which damages the surrounding ecosystem and threaten human *** kind of MOF is stable and convenient to prepare,but has the disadvantage of low adsorption capacity,limiting its wide *** this end,a novel formic acid and amino modified MOFs were prepared,referred to as Form-UiO-66-NH_(2).Due to the modification of formic acid,its specific surface area,pore size,and crystal size were effectively expanded,and the adsorption capacity of Cr6+was significantly *** optimal conditions,Form-UiO-66-NH_(2) exhibited an excellent adsorption capacity(338.98 mg/g),∼10 times higher than that reported for unmodified Zr-based MOFs and most other *** in-depth study on the photoelectronic properties and pH confirmed that the adsorption mechanism of Form-UiO-66-NH2 to Cr^(6+)was electrostatic *** modification,the improvement of Cr^(6+)adsorption capacity by Form-UiO-66-NH_(2) was attributed to the expansion of its specific surface area and the increase in its surface *** present study revealed an important finding that Form-UiO-66-NH_(2) elucidated selective adsorption to Cr^(6+)in mixed wastewater containing toxic heavymetal ions and common nonmetallic water quality *** research provided a new acid and amino functionalization perspective for improving the adsorption capacity of Zr-based MOF adsorbents while simultaneously demonstrating their pertinence to target contaminant adsorption.

关键词： Acid-modified UiO-66-NH_(2) Excellent adsorption capacity Hexavalent chromium Selective adsorption

Synthesis and Aqueous Solution Viscosity of Hydrophobically Modified Xanthan Gum

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Journal of Beijing Institute of Technology 2007年第3期16卷 346-351页

作者：钱晓琳吴文辉于培志王建全 School of Materials Science and Engineering Beijing Institute of Technology Exploration & production research Institute China Petroleum & Chemical Corporation

Two xanthan gum derivatives hydrophobically modified by 4 or 8 tetradecyl chains per 100 xanthan gum structure units were synthesized. The derivatives were studied by scanning electron microscope and pyrene fluorescence spectrometry. And the aqueous solution apparent viscosity of the derivatives was investi- gated. The results indicate that the network of the derivatives with more hydrophobic groups is closer and tighter. With increasing of alkyl chain substitution degree, the hydrophobically associating interactions enhance in aqueous solution. Aqueous solution apparent viscosity of the derivatives increases with increasing of polymer concentration and alkyl substitution degree, and decreases with the increase of temperature. In the brine solution, the strong viscosity enhancement phenomenon appears. The interaction between the derivatives and surfactant sodium dodecylbenzene sulfonate is strong.

关键词： xanthan gum hydrophobically modified association viscosity

Paleotopographic controls on facies development in various types of braid-delta depositional systems in lacustrine basins in China

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Geoscience Frontiers 2015年第4期6卷 579-591页

作者： Dong Feng Hongwen Deng Zhan Zhou Xiaopeng Gao Longtao Cui School of Energy Resources China University of Geosciences (Beijing) Zhanjiang Branch of China National Offshore Oil Corporation Ltd SINOPEC Exploration and production research Institute

Braid-delta depositional systems are widely developed in most continental basins in China. research indicates that, for different types of braid delta, the facies sequence and association, which are critical to the prediction of the distribution of reservoirs, differ greatly. This study illustrates the differences in braid-delta depositional systems in terms of sedimentary characteristics, associated systems and reser- voir distributions using three typical paleodeltas in western China： the Zhenbei delta of the upper Triassic Yanchang Formation in the Ordos Basin, the Yuanba delta of the upper Triassic Xujiahe Formation in the Sichuan Basin and the Jimsar delta of the upper Permian Wutonggou Formation in the Junggar Basin. A stratigraphic framework was established using seismic data, logs and cores by choosing stable mud sections as regional correlation markers and, topographies of these deltas were reconstructed based on the decompaction and paleobathymetric corrections. Based on both the paleotopography of these deltas and the differences of their sedimentary facies, these braided deltas can be classified into two systems： steep-gradient braid-delta-turbidite system and low-gradient braid-delta-lacustrine system. Moreover, the low-gradient braid-delta-lacustrine system can be further divided into interfingered and sharp contact sub-types according to the contact relation between the delta sands and lacustrine muds. This study shows that the paleotopography of basin margins strongly controls the accommodation as braid deltas prograde into lacustrine basins and, influences the location of the shoreline in response to changes in the lake level. Furthermore, paleotopography plays a significant role in facies and reservoir distribution which is important for petroleum exploration and development.

关键词： Paleotopography Braid deltas Facies Basin margin Lacustrine basins

Perturbations of the ileal mycobiota by necrotic enteritis in broiler chickens

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Journal of Animal Science and Biotechnology 2022年第2期13卷 520-535页

作者： Qing Yang Jing Liu Kelsy J.Robinson Melanie A.Whitmore Sydney N.Stewart Guolong Zhang Department of Animal and Food Sciences Oklahoma State UniversityStillwaterOKUSA Poultry production and Product Safety research Unit USDA-Agricultural Research ServiceFayettevilleARUSA Safety and Security Division Institute for Public ResearchCNAArlingtonVAUSA

Background:Intestinal microbiota is critical for maintaining animal health and ***,involvement of the fungal community,also known as the mycobiota,in animal health and disease is poorly *** study was aimed to examine the association between the intestinal mycobiota and the severity of necrotic enteritis(NE),an economically significant poultry ***:A total of 90 day-of-hatch Cobb broilers were infected with Eimeria maxima on d 10,followed by an oral challenge with *** on d 14 to induce NE,while another 10 broilers were served as mock-infected *** d 17,the lesions in the jejunum were scored,and the ileal digesta were subjected to DNA isolation and real-time PCR quantification of total bacterial and fungi *** transcribed spacer 2(ITS2)amplicon sequencing was also performed to profile the ileal mycobiota *** in the ileal mycobiota in response to NE were *** correlation analysis was further conducted to identify the correlations between relative abundances of individual ileal fungi and the severity of ***:While the total bacterial population in the ileum was increased by 2-to 3-fold in NE chickens,the total fungal population was progressively declined in more exacerbated NE,with the most severely infected chickens showing a nearly 50-fold reduction relative to mock-infected *** of the ileal mycobiota also tended to reduce in chickens with NE(P=0.06).Compositionally,among 30 most abundant fungal amplicon sequence variants(ASVs),11 were diminished and 7 were enriched(P0.05).Multiple Wallemia and Aspergillus species were markedly diminished in NE(P<0.05)and also showed a significant negative correlation with NE severity(P<0.05).Conclusions:Dysbiosis of the ileal mycobiota is induced evidently by NE and the extent of the dysbiosis is positively correlated with disease ***

关键词： Antimicrobial resistance C.perfringens Dysbiosis ITS sequencing Microbiome Mycobiota Necrotic enteritis Poultry

Comparative assessment for removal of anionic dye from water by different waste-derived biochar vis a vis reusability of generated sludge

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Biochar 2022年第1期4卷 986-1002页

作者： Mayank Singh MohdAhsan Versha Pandey Anupama Singh Disha Mishra Neerja Tiwari Pooja Singh Tanmoy Karak Puja Khare Crop production and Protection DivisionCSIR-Central Institute of Medicinal and Aromatic PlantsLucknow 226015India Phytochemistry Division CSIR-Central Institute of Medicinal and Aromatic PlantsLucknow 226015India Upper Assam Advisory Centre Tea Research AssociationDikomDibrugarh 786101AssamIndia Academy of Scientific and Innovative research(AcSIR) GaziabadIndia Biotechnology Division Central Institute of Medicinal and Aromatic PlantsLucknow 226015India

In this study,four biochars prepared from different crop residue waste *** bagasse(SBB),coconut shell(CNB),paddy straw(PDB),and distilled waste of lemongrass(LGB)were evaluated for removal of Remazol Brilliant Blue R from the aqueous *** RBBR adsorption capacities of biochar were 97-79%for SBB,99.9-99.47%for CNB,66.1-48%for PDB,and 78-68%for LGB,dominantly controlled by their aromaticity and mineral *** Langmuir and Freundlich isotherms and pseudo-second-order kinetic models have described the chemisorption of RBBR on biochar *** thermodynamic data suggested that adsorption was spontaneous and *** biochars demonstrated excellent reusability(till four cycles with 50-61%regeneration).The purified water and biochar dye sludge demonstrated no *** findings obtained in this study may provide supports for the potential of biochars for anionic dye removal from water and utilization of generated sludge for zero waste-producing technologies in the future.

关键词： Biochar Remazol Brilliant Blue R Dye Adsorption Biochar dye sludge