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Ecological risk assessment of heavy metals in sediments of Xiawan Port based on modified potential ecological risk index 被引量:40
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作者 祝慧娜 袁兴中 +7 位作者 曾光明 蒋敏 梁婕 张长 尹娟 黄华军 刘智峰 江洪炜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第6期1470-1477,共8页
Modified potential ecological risk index (MRI) was proposed based on the potential ecological risk index (RI) and risk assessment code (RAC) by modifying an index. The modified index was relevant to the chemical... Modified potential ecological risk index (MRI) was proposed based on the potential ecological risk index (RI) and risk assessment code (RAC) by modifying an index. The modified index was relevant to the chemical speciation of heavy metals. Xiawan Port, a typical region contaminated by industrial production, was selected as a case study area. The total concentrations and chemical speciation of heavy metals in sediments of Xiawan Port were analyzed. The experimental data indicate that Xiawan Port is seriously polluted by heavy metals, especially by Cd. The risks of heavy metals are evaluated by RI, RAC and MRI, respectively. The resluts of MRI show that the risks of heavy metals are in the decreasing order of Cd〉Pb〉Cu〉Zn. Comparison of results by different methods reveals that MRI integrates the characters of RI and RAC. MRI is recognized to be useful for risk managemnt of heavy metals in sediments. 展开更多
关键词 heavy metals chemical speciation modified potential ecological risk index SEDIMENTS Xiawan Port
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Models for amplitude fluctuation of underwater acoustic narrow band signal based on modified modal scintillation index 被引量:2
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作者 安良 方世良 陈励军 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期235-241,共7页
A self-normalized statistic the modified modal scintillation index MMSI is proposed and defined as the variance of the modulus of modal excitation normalized by the square of its expected value over some observation i... A self-normalized statistic the modified modal scintillation index MMSI is proposed and defined as the variance of the modulus of modal excitation normalized by the square of its expected value over some observation intervals.It is proved in an analytical form that the MMSI is a depth dependent signature and independent of the source level and the source range under the condition of the ideal waveguide while the classical modal scintillation index MSI depends on both the source level and the source range.The MSI and the MMSI in the Pekeris waveguide at 70 Hz are simulated with different source levels and source ranges by the Kraken normal mode model.The simulation results are consistent with the theoretical deduction.The MMSI probability density functions PDFs of different normal modes for surface and submerged sources are calculated using the mode filtering methods with the same variations of vertical motions.It is indicated that the PDFs can be used to separate the submerged and the surface sources except for the fourth mode. 展开更多
关键词 modified modal scintillation index amplitudefluctuation mode filtering Pekeris waveguide
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Modified shock index and mortality rate of emergency patients 被引量:12
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作者 Ye-cheng Liu Ji-hai Liu +6 位作者 Zhe Amy Fang Guang-liang Shan Jun Xu Zhi-wei Qi Hua-dong Zhu Zhong Wang Xue-zhong Yu 《World Journal of Emergency Medicine》 CAS 2012年第2期114-117,共4页
BACKGROUND:This study aimed to determine whether modified shock index(MSI)is associated with mortality that is superior to heart rate,blood pressure,or the shock index(SI).in emergency patients.METHODS:A retrospective... BACKGROUND:This study aimed to determine whether modified shock index(MSI)is associated with mortality that is superior to heart rate,blood pressure,or the shock index(SI).in emergency patients.METHODS:A retrospective database review was performed on 22 161 patients who presented to Peking Union Medical College Hospital Emergency Department and received intravenous fluids from January 1 to December 31,2009.We gathered data of the patients on age,gender,vital signs,levels of consciousness,presenting complaints,and SI and MSI were calculated for all patients.RESULTS:Multivariate regression analysis was performed to determine the correlation between risk factors and outcome.There is a significant correlation between emergency patient mortality rate and patient's vital signs obtained at the triage desk(HR>120 beats/min,systolic BP<90 mmHg,diastolic BP<60 mmHg).MSI is a stronger predictor of emergency patient mortality compared to heart rate and blood pressure alone,whereas SI does not have a significant correlation with emergency patient mortality rate.CONCLUSION:MSI is a clinically significant predictor of mortality in emergency patients.It may be better than using heart rate and blood pressure alone.SI is not significantly correlated with the mortality rate of the emergency patient. 展开更多
关键词 Emergency department modified shock index Mortality rate PREDICTOR Multivariate regression analysis
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A Modified Temperature-Vegetation Dryness Index(MTVDI)for Assessment of Surface Soil Moisture Based on MODIS Data 被引量:1
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作者 WANG Hao LI Zongshan +2 位作者 ZHANG Weijuan YE Xin LIU Xianfeng 《Chinese Geographical Science》 SCIE CSCD 2022年第4期592-605,共14页
Spatio-temporal dynamic monitoring of soil moisture is highly important to management of agricultural and vegetation eco-systems.The temperature-vegetation dryness index based on the triangle or trapezoid method has b... Spatio-temporal dynamic monitoring of soil moisture is highly important to management of agricultural and vegetation eco-systems.The temperature-vegetation dryness index based on the triangle or trapezoid method has been used widely in previous studies.However,most existing studies simply used linear regression to construct empirical models to fit the edges of the feature space.This requires extensive data from a vast study area,and may lead to subjective results.In this study,a Modified Temperature-Vegetation Dryness Index(MTVDI)was used to monitor surface soil moisture status using MODIS(Moderate-resolution Imaging Spectroradiometer)remote sensing data,in which the dry edge conditions were determined at the pixel scale based on surface energy balance.The MTVDI was validated by field measurements at 30 sites for 10 d and compared with the Temperature-Vegetation Dryness Index(TVDI).The results showed that the R^(2) for MTVDI and soil moisture obviously improved(0.45 for TVDI,0.69 for MTVDI).As for spatial changes,MTVDI can also better reflect the actual soil moisture condition than TVDI.As a result,MTVDI can be considered an effective method to monitor the spatio-temporal changes in surface soil moisture on a regional scale. 展开更多
关键词 surface soil moisture Temperature-Vegetation Dryness index(TVDI) vegetation index MODIS modified Temperature-Vegetation Dryness index(MTVDI)
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A modified TOPMODEL introducing the bedrock surface topographic index in Huangbengliu watershed,China 被引量:1
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作者 QIU An-ni ZHANG Yan-jun +4 位作者 WANG Gen-xu CUI Jun-fang SONG Yuan-xin SUN Xiang-yang CHEN Li 《Journal of Mountain Science》 SCIE CSCD 2022年第12期3517-3532,共16页
Subsurface stormflow is a dominant runoff mechanism in steep humid mountainous areas.An insite measurement of subsurface stormflow suggests that the bedrock surface plays an important role in the runoff generation and... Subsurface stormflow is a dominant runoff mechanism in steep humid mountainous areas.An insite measurement of subsurface stormflow suggests that the bedrock surface plays an important role in the runoff generation and routing process,which was rarely adopted in hydrological modelling studies.To improve the runoff simulation performance,the bedrock surface topographic index is introduced,and a modified TOPMODEL based on the bedrock surface topographic index is developed to simulate the runoff.The modified TOPMODEL is applied to the Huangbengliu(HBL),a steep watershed in Gongga Mountain,and proved to be more appropriate for the HBL watershed,especially for peak simulation.The Nash-Sutcliffe model efficiency(NSE)is improved from 0.24 to 0.58 in the calibration period and from 0.40 to 0.62 in the verification period.The result of this study can advance the understanding of the mechanism of flash floods and contribute flood control and disaster prevention in the HBL watershed and similar areas. 展开更多
关键词 Subsurface stormflow Flash flood modified TOPMODEL Bedrock surface topographic index Gongga Mountain
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Differentiation of Algal Blooms and Aquatic Vegetation in Chinese Lakes Using Modified Vegetation Presence Frequency Index Method
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作者 PU Jing SONG Kaishan +4 位作者 LIU Ge WEN Zhidan FANG Chong HOU Junbing LV Yunfeng 《Chinese Geographical Science》 SCIE CSCD 2022年第5期792-807,共16页
Algal blooms in lakes have become a common global environmental problem. Nowadays, remote sensing is widely used to monitor algal blooms in lakes due to the macroscopic, fast, real-time characteristics. However, it is... Algal blooms in lakes have become a common global environmental problem. Nowadays, remote sensing is widely used to monitor algal blooms in lakes due to the macroscopic, fast, real-time characteristics. However, it is often difficult to distinguish between algal blooms and aquatic vegetation due to their similar spectral characteristics. In this paper, we used modified vegetation presence frequency index(VPF) based on Moderate-resolution Imaging Spectroradiometer(MODIS) imagery to distinguish algal blooms from aquatic vegetation, and analyzed the spatial and temporal variations of algal blooms and aquatic vegetation from a phenological perspective for five large natural lakes with frequent algal bloom outbreaks in China from 2019 to 2020. We simplified the VPF method to make it with a higher spatial transferability so that it could be applied to other lakes in different climatic zones. Through accuracy validation, we found that the modified VPF method can effectively distinguish between algal blooms and aquatic vegetation, and the results vary from lake to lake. The highest accuracy of 97% was achieved in Hulun Lake, where the frequency of algal outbreaks is low and the extent of aquatic vegetation is stable, while the lowest accuracy of 76% was achieved in Dianchi Lake, which is rainy in summer and the lake is small. Analyses suggests that the time period when algal blooms occur most frequently might not coincide with that when they have the largest area. However, in most cases these two are close in terms of time period. The modified VPF method has a broad scope of application, is easy to implement, and has a high practical value. Furthermore, the method could be established using only a small amount of measured data, which is useful for water quality monitoring on large spatial scales. 展开更多
关键词 algal blooms aquatic vegetation modified vegetation presence frequency index(VPF) PHENOLOGY LAKE
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Joint inversion of gravity and vertical gradient data based on modified structural similarity index for the structural and petrophysical consistency constraint
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作者 Sheng Liu Xiangyun Wan +6 位作者 Shuanggen Jin Bin Jia Quan Lou Songbai Xuan Binbin Qin Yiju Tang Dali Sun 《Geodesy and Geodynamics》 EI CSCD 2023年第5期485-499,共15页
Joint inversion is one of the most effective methods for reducing non-uniqueness for geophysical inversion.The current joint inversion methods can be divided into the structural consistency constraint and petrophysica... Joint inversion is one of the most effective methods for reducing non-uniqueness for geophysical inversion.The current joint inversion methods can be divided into the structural consistency constraint and petrophysical consistency constraint methods,which are mutually independent.Currently,there is a need for joint inversion methods that can comprehensively consider the structural consistency constraints and petrophysical consistency constraints.This paper develops the structural similarity index(SSIM)as a new structural and petrophysical consistency constraint for the joint inversion of gravity and vertical gradient data.The SSIM constraint is in the form of a fraction,which may have analytical singularities.Therefore,converting the fractional form to the subtractive form can solve the problem of analytic singularity and finally form a modified structural consistency index of the joint inversion,which enhances the stability of the SSIM constraint applied to the joint inversion.Compared to the reconstructed results from the cross-gradient inversion,the proposed method presents good performance and stability.The SSIM algorithm is a new joint inversion method for petrophysical and structural constraints.It can promote the consistency of the recovered models from the distribution and the structure of the physical property values.Then,applications to synthetic data illustrate that the algorithm proposed in this paper can well process the synthetic data and acquire good reconstructed results. 展开更多
关键词 Joint inversion Gravity and vertical gradient data modified structural similarity index
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Spatiotemporal variations in ecological quality of Otindag Sandy Land based on a new modified remote sensing ecological index
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作者 ZHAO Xiaohan HAN Dianchen +2 位作者 LU Qi LI Yunpeng ZHANG Fangmin 《Journal of Arid Land》 SCIE CSCD 2023年第8期920-939,共20页
Otindag Sandy Land in China is an important ecological barrier to Beijing;the changes in its ecological quality are major concerns for sustainable development and planning of this area.Based on principal component ana... Otindag Sandy Land in China is an important ecological barrier to Beijing;the changes in its ecological quality are major concerns for sustainable development and planning of this area.Based on principal component analysis and path analysis,we first generated a modified remote sensing ecological index(MRSEI)coupled with satellite and ground observational data during 2001–2020 that integrated four local indicators(greenness,wetness,and heatness that reflect vegetation status,water,and heat conditions,respectively,as well as soil erosion).Then,we assessed the ecological quality in Otindag Sandy Land during 2001–2020 based on the MRSEI at different time scales(i.e.,the whole year,growing season,and non-growing season).MRSEI generally increased with an upward rate of 0.006/a during 2001–2020,with clear seasonal and spatial variations.Ecological quality was significantly improved in most regions of Otindag Sandy Land but degraded in the southern part.Regions with ecological degradation expanded to 18.64%of the total area in the non-growing season.The area with the worst grade of MRSEI shrunk by 15.83%of the total area from 2001 to 2020,while the area with the best grade of MRSEI increased by 9.77%of the total area.The temporal heterogeneity of ecological conditions indicated that the improvement process of ecological quality in the growing season may be interrupted or deteriorated in the following non-growing season.The implementation of ecological restoration measures in Otindag Sandy Land should not ignore the seasonal characteristics and spatial heterogeneity of local ecological quality.The results can explore the effectiveness of ecological restoration and provide scientific guides on sustainable development measures for drylands. 展开更多
关键词 ecological quality modified remote sensing ecological index principal component analysis path analysis Otindag Sandy Land dryland ecosystem
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Analyzing the influences of two types of El Nino on Tropical Cyclone Genesis with a modified genesis potential index
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作者 王法明 杨宇星 杨磊 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第2期452-465,共14页
To understand the impacts of large-scale circulation during the evolution of E1 Nifio cycle on tropical cyclones (TC) is important and useful for TC forecast. Based on best-track data from the Joint Typhoon Warning ... To understand the impacts of large-scale circulation during the evolution of E1 Nifio cycle on tropical cyclones (TC) is important and useful for TC forecast. Based on best-track data from the Joint Typhoon Warning Center and reanalysis data from National Centers for Environmental Prediction for the period 1975- 2014, we investigated the influences of two types of E1 Nifio, the eastern Pacific E1 Nifio (EP-E1 Nifio) and central Pacific E1 Nifio (CP-E1 Nifio), on global TC genesis. We also examined how various environmental factors contribute to these influences using a modified genesis potential index (MGPI). The composites reproduced for two types of E1 Nifio, from their developing to decaying phases, were able to qualitatively replicate observed cyclogenesis in several basins except for the Arabian Sea. Certain factors of MGPI with more influence than others in various regions are identified. Over the western North Pacific, five variables were all important in the two E1Nifio types during developing summer (July-August-September) and fall (October- November-December), and decaying spring (April-May-June) and summer. In the eastern Pacific, vertical shear and relative vorticity are the crucial factors for the two types of El Nifio during developing and decaying summers. In the Atlantic, vertical shear, potential intensity and relative humidity are important for the opposite variation of EP- and CP-EI Nifios during decaying summers. In the Southern Hemisphere, the five variables have varying contributions to TC genesis variation during peak season (January-February-March) for the two types of E1 Nifio. In the Bay of Bengal, relative vorticity, humidity and omega may be responsible for clearly reduced TC genesis during developing fall for the two types and slightly suppressed TC cyclogenesis during EP-E1 Nifio decaying spring. In the Arabian Sea, the EP-E1 Nifio generates a slightly positive anomaly of TC genesis during developing falls and decaying springs, but the MGPI failed to capture this variation. 展开更多
关键词 two types of E1 Nifio tropical cyclone (TC) modified genesis potential index
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A novel multimode process monitoring method integrating LCGMM with modified LFDA 被引量:4
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作者 任世锦 宋执环 +1 位作者 杨茂云 任建国 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1970-1980,共11页
Complex processes often work with multiple operation regions, it is critical to develop effective monitoring approaches to ensure the safety of chemical processes. In this work, a discriminant local consistency Gaussi... Complex processes often work with multiple operation regions, it is critical to develop effective monitoring approaches to ensure the safety of chemical processes. In this work, a discriminant local consistency Gaussian mixture model(DLCGMM) for multimode process monitoring is proposed for multimode process monitoring by integrating LCGMM with modified local Fisher discriminant analysis(MLFDA). Different from Fisher discriminant analysis(FDA) that aims to discover the global optimal discriminant directions, MLFDA is capable of uncovering multimodality and local structure of the data by exploiting the posterior probabilities of observations within clusters calculated from the results of LCGMM. This may enable MLFDA to capture more meaningful discriminant information hidden in the high-dimensional multimode observations comparing to FDA. Contrary to most existing multimode process monitoring approaches, DLCGMM performs LCGMM and MFLDA iteratively, and the optimal subspaces with multi-Gaussianity and the optimal discriminant projection vectors are simultaneously achieved in the framework of supervised and unsupervised learning. Furthermore, monitoring statistics are established on each cluster that represents a specific operation condition and two global Bayesian inference-based fault monitoring indexes are established by combining with all the monitoring results of all clusters. The efficiency and effectiveness of the proposed method are evaluated through UCI datasets, a simulated multimode model and the Tennessee Eastman benchmark process. 展开更多
关键词 Multimode process monitoring Discriminant local consistency Gaussian mixture model modified local Fisher discriminant analysis Global fault detection index Tennessee Eastman process
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The Schultz Index and Schultz Polynomial of the Jahangir Graphs <i>J </i><sub>5, <i>m </i></sub> 被引量:2
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作者 Mohammad Reza Farahani Wei Gao 《Applied Mathematics》 2015年第14期2319-2325,共7页
Let G be simple connected graph with the vertex and edge sets V (G) and E (G), respectively. The Schultz and Modified Schultz indices of a connected graph G are defined as and , where d (u, v) is the distance between ... Let G be simple connected graph with the vertex and edge sets V (G) and E (G), respectively. The Schultz and Modified Schultz indices of a connected graph G are defined as and , where d (u, v) is the distance between vertices u and v?;dv is the degree of vertex v of G. In this paper, computation of the Schultz and Modified Schultz indices of the Jahangir graphs J5,m is proposed. 展开更多
关键词 WIENER index Schultz index modified Schultz index Distance Jahangir GRAPHS
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How Polymers Behave as Viscosity Index Improvers in Lubricating Oils 被引量:4
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作者 Michael J. Covitch Kieran J. Trickett 《Advances in Chemical Engineering and Science》 2015年第2期134-151,共18页
One of the requirements of engine lubricating oil is that it must have a low enough viscosity at low temperatures to assist in cold starting and a high enough viscosity at high temperatures to maintain its load-bearin... One of the requirements of engine lubricating oil is that it must have a low enough viscosity at low temperatures to assist in cold starting and a high enough viscosity at high temperatures to maintain its load-bearing characteristics. Viscosity Index (VI) is one approach used widely in the lubricating field to assess the variation of viscosity with temperature. The VI of both mineral and synthetic base oils can be improved by the addition of polymeric viscosity modifiers (VMs). VI improvement by VMs is widely attributed to the polymer coil size expanding with increasing temperature. However, there is very little physical data supporting this generally accepted mechanism. To address this issue, intrinsic viscosity measurements and Small-Angle Neutron Scattering (SANS) have been used to study the variation of polymer coil size with changing temperature and concentration in a selection of solvents. The results will show that coil size expansion with temperature is not necessary to achieve significant elevation of viscosity index. 展开更多
关键词 VISCOSITY index IMPROVER VISCOSITY modifiER Polymer SMALL-ANGLE NEUTRON Scattering RHEOLOGY
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Projections of the impacts of climate change on the water deficit and on the precipitation erosive indexes in Mantaro River Basin, Peru 被引量:1
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作者 Sly C.WONGCHUIG Carlos R.MELLO Sin C.CHOU 《Journal of Mountain Science》 SCIE CSCD 2018年第2期264-279,共16页
Projections of climate change are essential to guide sustainable development plans in the tropical Andean countries such as Peru. This study assessed the projections of precipitation and potential evaporation, rain er... Projections of climate change are essential to guide sustainable development plans in the tropical Andean countries such as Peru. This study assessed the projections of precipitation and potential evaporation, rain erosive potential, and precipitation concentration in the Mantaro River Basin, in the Peruvian Andes, which is important for agriculture and energy production in Peru. We assumed the Intergovernmental Panel on Climate Change (IPCC) AIB greenhouse gas emission scenario and simulated the global climate change by the HadCM3 global climate model. Due to the steepness of the mountain slopes and the narrowness of the river valley, this study uses the downscaling of the global model simulations by the regional Eta model down to 2o-km resolution. The downscaling projections show decrease in the monthly precipitation with respect to the baseline period, especially during the rainy season, between February and April, until the end of the 21st century. Meanwhile, a progressive increase in the monthly evaporation from the baseline period is projected. The Modified Fournier Index (MFI) shows a statistically significant downward trend in the Mantaro River Basin, whieh suggests a possible reduction in the rain erosive potential. The Precipitation Concentration Index (PCI) shows a statistically significant increasing trend, which indicates increasingly more irregular temporal distribution of precipitation towards the end of the century. The results of this study allow us to conclude that there should be a gradual increase in water deficit and precipitation concentration. Both changes can be negative for agriculture, power generation, and water supply in the Mantaro River Basin in Peru. 展开更多
关键词 PRECIPITATION EVAPORATION PrecipitationConcentration index (PCI) modified Fournier index(MFI) Climate change Tropical Andes
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Determination of Work Index of Gyel-Bukuru Columbite Ore in Plateau State, Nigeria 被引量:1
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作者 Oladunni Oyelola Alabi Shehu Aliyu Yaro +2 位作者 George Thomas Dungka Ferdinand Asuke Emmanuel Toi Dauda 《Journal of Minerals and Materials Characterization and Engineering》 2015年第3期194-203,共10页
Determination of the work index of Gyel-Buruku columbite ore sample in Plateau state, Nigeria, was investigated. The sample of the columbite ore was sourced from Gyel village in Jos East Local Government Area of Plate... Determination of the work index of Gyel-Buruku columbite ore sample in Plateau state, Nigeria, was investigated. The sample of the columbite ore was sourced from Gyel village in Jos East Local Government Area of Plateau state, Nigeria. The “reference ores (granites)” samples were sourced from Jiche and Gurum villages of Plateau state respectively. The reference ores and columbite ore of known weights were ground and pulverized. 80% passing size for the columbite ore, Jiche and Gurum granites samples was obtained at 100 μm sieve size for the feeds and products respectively. The work indexes of reference ores i.e. Jiche and Gurum granites were used to calculate the work index of the Gyel columbite ore sample. The values of 3.42 kWh/ton and 2.72 kWh/ton were obtained respectively for the two different reference granites ores samples used and 3.07 kWh/ton was calculated as their average and determined as the value of the work index of the Gyel-Bukuru columbite ore sample. This work index value obtained for the Gyel-Buruku columbite ore sample lies favourably within the work indexes of 3.94 - 10.81 kWh/ton for columbite minerals sighted in the literatures. 展开更多
关键词 Work index Gyel COLUMBITE ORE modified Reference MINERALS
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Quantitative Analysis on Distribution of Modifier in Microstructure of SBS Modifi ed Asphalt 被引量:1
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作者 殷巍 杨群 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第4期740-744,共5页
A method was developed to make a quantitative analysis of the microstructure of asphalt modified with styrene-butadiene-styrene block(SBS) copolymer. Moreover, both mixed and branched SBS were employed in the prepar... A method was developed to make a quantitative analysis of the microstructure of asphalt modified with styrene-butadiene-styrene block(SBS) copolymer. Moreover, both mixed and branched SBS were employed in the preparation of modified asphalt. By sampling specimens from the top, middle, and bottom, a number of microscope slides were made and 400 times micro images were gained. Binarized with the software of MATLAB, the images then went to the process of distribution test, when four typical distributions were employed to investigate the distribution of modifi er spread in asphalt. The distribution characteristic and its parameter were both found. The results show that asphalt phase clearly obeys Poisson distribution, and its parameter, λ, is bond up with the condition SBS performs in. Based on this parameter, indexes can be set up to evaluate the structure of the mixture and its performance as well. Compared with that modifi ed with mixed SBS, the asphalt modifi ed with branched SBS has better performance but worse stability, for it is easier to segregate. 展开更多
关键词 SBS modifi ed asphalt microstructure quantitative index distribution characteristic
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Do parental coronary heart disease risk factors(non-modifiable) effect their young ones? 被引量:1
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作者 Arun Kumar 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第2期113-123,共11页
Objective:To study the differences between the lipid profiles of the subjects whose parents are having known non-modifiable risk factors such as obesity,hypertension(HTN),myocardial infarction and diabetes,and compare... Objective:To study the differences between the lipid profiles of the subjects whose parents are having known non-modifiable risk factors such as obesity,hypertension(HTN),myocardial infarction and diabetes,and compare them with the lipid profiles of the subjects whose parents are not having those risk factors.Methods:A total of 402 subjects were recruited to this study.A detailed questionnaire which included information on the past medical history,height,weight,blood pressure,physical activity,smoke,alcohol,family history of coronary heart disease,HTN.diabetics and obesity.Basic demographic data and dietary habits were completed by all participants.Blood samples were obtained from all subjects after 14 h.Lipid profiles were analyzed using automated analyzer.The results were analyzed using SPSS software packages.Results:The mean body mass index of the population was well below the cut-off value of obesity(>24.5 kg/m") and high risk of future cardiovascular disorder(CVD) events in this age group.The mean levels of total cholesterol(TC),triglycerides(TG) and TC/high density lipoprotein(HDL) were less than the risk levels indicative of future CVD events according to the ATP Ⅲ cut-off values.However the mean HDL level in our population was slightly greater than the cut-off value while the mean low density lipoprotein level was almost similar to the risk level.Differences were observed when the subjects without history of maternal obesity were compared with subjects with history of maternal obesity.The greater percentage of subjects who are having risk levels of body mass index.TC.low density lipoprotein.TG.and TC/HDI.indicated that maternal obesity contributed to the greater susceptibility of developing CVD risk in their offspring.Conclusions:Advancing age may result in changes that could be atherogenic in the future.Such atherogenic changes have already initialed when the subjects are about 21 years old.The incidence of atherogenic changes is far greater when mothers who are having any of the risk factors such as obesity,diabetes,HTN and myocardial infarction than that fathers who are havine similar risk factors. 展开更多
关键词 Non-modifiable cardiovascular risk factors Lipid profile Obesity NEPALESE BASAL metabolic index Athcrogcnesis
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上面层改性沥青混合料低温性能综合对比评价 被引量:1
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作者 查旭东 谭仕杰 +1 位作者 邹博 王旭东 《长沙理工大学学报(自然科学版)》 CAS 2024年第1期30-38,共9页
【目的】分析足尺路面试验环道所用7种上面层细粒式改性沥青混合料的低温性能。【方法】通过小梁低温弯曲、中梁线收缩系数和法国M2F梯形梁动态模量3种室内试验开展研究及相关性分析,并应用多指标试验结果的无量纲归一化赋权求和法进行... 【目的】分析足尺路面试验环道所用7种上面层细粒式改性沥青混合料的低温性能。【方法】通过小梁低温弯曲、中梁线收缩系数和法国M2F梯形梁动态模量3种室内试验开展研究及相关性分析,并应用多指标试验结果的无量纲归一化赋权求和法进行综合对比评价。【结果】最大弯拉应变、应变能密度、线收缩系数、复模量和相位角均可作为改性沥青混合料低温性能的合理评价指标;对比改性沥青类型,采用低温延性强的SBS改性沥青制备的混合料低温性能最优,橡胶沥青混合料的次之,掺抗车辙剂能增强SBS改性AC类混合料的低温性能;对比矿料合成级配,SMA类的低温性能最优,SBS改性AC类中粗集料含量越低,其低温性能越好;多孔排水式高黏SBS改性PAC类具有优良的黏弹性和低温收缩性能。【结论】评价结果可为环道沥青路面低温性能长期监测对比提供参考。 展开更多
关键词 道路工程 上面层 改性沥青混合料 低温性能 评价指标
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改良俯卧位通气对急性呼吸窘迫综合征患者呼吸功能及预后的影响 被引量:2
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作者 白奎 郭凤杰 秦国泉 《河南医学研究》 CAS 2024年第3期451-455,共5页
目的 探究改良俯卧位通气对急性呼吸窘迫综合征(ARDS)患者血流动力学、呼吸动力学及预后的影响。方法 前瞻性选取河南大学第一附属医院2020年3月至2022年6月收治的98例ARDS患者作为研究对象,通过随机数字表法分为A、B组。通过随机及前... 目的 探究改良俯卧位通气对急性呼吸窘迫综合征(ARDS)患者血流动力学、呼吸动力学及预后的影响。方法 前瞻性选取河南大学第一附属医院2020年3月至2022年6月收治的98例ARDS患者作为研究对象,通过随机数字表法分为A、B组。通过随机及前瞻性平行对照临床研究,评价不同通气方式在ARDS患者中的作用,其中A组52例接受改良式俯卧位通气,B组46例接受传统俯卧位通气。对比两组患者干预前、干预后(俯卧位通气4 h后)血流动力学[心率(HR)、平均动脉压、中心静脉压]、呼吸动力学指标[气道阻力、静态肺顺应性(Cst)]、氧合指数及腹腔压力的变化。比较两组患者不良事件发生情况,对所有患者进行3个月随访,比较两组患者病死率情况。结果 (1)A组机械通气时间低于B组,撤机成功率高于B组(P<0.05);(2)干预后,两组患者HR均较干预前上升,干预前后差值具有统计学意义(P<0.05);(3)干预后,两组Cst水平均较干预前上升且A组高于B组,干预前后差值具有统计学意义(P<0.05);(4)干预后,两组腹腔压力均较治疗前上升且A组低于B组,干预前后差值具有统计学意义(P<0.05);(5)A组不良事件总发生率[7.69%(4/52)]低于B组[23.91%(11/46)](P<0.05);(6)随访3个月结果显示,A组病死率[23.08%(12/52)]低于B组[43.48%(20/46)](P<0.05)。结论 改良俯卧位通气对ARDS血流动力学、呼吸动力学及相关指标均有显著的改善效果,不良事件的发生率较低且预后状况良好,值得临床参考借鉴。 展开更多
关键词 改良俯卧位通气 急性呼吸窘迫综合征 静态肺顺应性 氧合指数 腹腔压力 预后
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加味调肝汤联合西药治疗肝郁肾虚型月经过少疗效及对患者子宫内膜厚度的影响 被引量:2
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作者 刘淑君 赵欣 +2 位作者 贾艳清 李晓瑜 潘龙 《陕西中医》 CAS 2024年第1期41-45,共5页
目的:研究加味调肝汤联合西药治疗肝郁肾虚型月经过少临床疗效及对患者子宫内膜厚度的影响。方法:选取肝郁肾虚型月经过少患者共124例,采用随机数字表法分为观察组和对照组,其中对照组62例采用戊酸雌二醇(E2)、地屈孕酮治疗,观察组62例... 目的:研究加味调肝汤联合西药治疗肝郁肾虚型月经过少临床疗效及对患者子宫内膜厚度的影响。方法:选取肝郁肾虚型月经过少患者共124例,采用随机数字表法分为观察组和对照组,其中对照组62例采用戊酸雌二醇(E2)、地屈孕酮治疗,观察组62例采用加味调肝汤联合戊酸雌二醇、地屈孕酮治疗。比较两组治疗效果、不良反应发生率,两组治疗前后中医证候积分、子宫内膜厚度、子宫血流阻力指数(RI)和卵泡期性激素水平。结果:观察组治疗总有效率为90.32%,较对照组总有效率75.81%高(P<0.05)。治疗前两组中医证候积分对比差异无统计学意义(P>0.05),治疗3个月后观察组上述积分较对照组更低(P<0.05)。治疗前两组卵泡期子宫内膜厚度、RI值比较,差异无统计学意义(P>0.05),治疗3个月后观察组卵泡期子宫内膜厚度较对照组更厚;RI较之于对照组更低(P<0.05)。治疗前两组卵泡期E2、FSH、LH水平比较无统计学差异(P>0.05);治疗3个月后观察组卵泡期性激素水平比对照组高(P<0.05)。观察组不良反应发生率为11.29%,与对照组的24.19%比较差异无统计学意义(P>0.05)。结论:加味调肝汤联合西药治疗肝郁肾虚型月经过少临床疗效比单用西药治疗效果更佳,能促进子宫内膜生长,降低RI值,调节卵泡期性激素水平。 展开更多
关键词 月经过少 子宫内膜厚度 肝郁肾虚型 加味调肝汤 性激素 子宫血流阻力指数
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玉屏风加减煎剂对德化黑鸡柔嫩艾美耳球虫的抗感染效果
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作者 林雪玲 林祚贵 +3 位作者 赖宝色 徐磊 刘志军 马玉芳 《福建农业学报》 CAS CSCD 北大核心 2024年第6期633-642,共10页
【目的】探明玉屏风加减煎剂对柔嫩艾美耳球虫(Eimeria tenella)感染德化黑鸡抗氧化、抗炎、免疫功能的影响及抗球虫效果。【方法】将120只45日龄德化黑鸡随机分为6组,分别是空白对照组(K组)、感染对照组(G组)、常山青蒿低剂量组(CQL组... 【目的】探明玉屏风加减煎剂对柔嫩艾美耳球虫(Eimeria tenella)感染德化黑鸡抗氧化、抗炎、免疫功能的影响及抗球虫效果。【方法】将120只45日龄德化黑鸡随机分为6组,分别是空白对照组(K组)、感染对照组(G组)、常山青蒿低剂量组(CQL组)、玉屏风加减低剂量组(YL组)、常山青蒿高剂量组(CQH组)、玉屏风加减高剂量组(YH组),除空白对照组外,其余各组均感染柔嫩艾美耳球虫,24 h后开始连续7 d饮水给药,第8 d测定比较各组抗球虫指数、免疫功能、抗氧化能力等指标的差异。【结果】与感染对照组(G组)相比,中药处理组CQH、YH、CQL、YL的血便、盲肠病变症状依次减轻。除CQH组外,其他组盲肠病变计分、盲肠黏膜下淋巴细胞密度显著或极显著下降(P<0.05或P<0.01);除CQH组OPG显著下降(P<0.05)外,其他3个中药组OPG下降极显著(P<0.01);YL组和YH组盲肠上皮细胞脱落计分极显著降低(P<0.01)。与CQL、CQH组相比,YL、YH组MDA、盲肠病变计分、盲肠上皮细胞脱落计分和OPG下降极显著(P<0.01)。与G组相比,4个中药组IL-6、 IFN-γ、TNF-α、丙二醛(MDA)含量极显著降低(P<0.01),而IL-2含量、 SIgA水平、谷胱甘肽过氧化物酶(GSH-Px)活性、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、总抗氧化能力(T-AOC)极显著升高(P<0.01);YL组IL-2含量、 SIgA水平、GSH-Px活性、SOD活性、CAT活性极显著增高(P<0.01),YH组GSH-Px、 SOD活性极显著升高(P<0.01)。与K组相比,G组、CQL组、YL组、CQH组、YH组的相对增重率分别是79.88%、 103.49%、 107.27%、 95.05%、 96.06%,抗球虫指数(anti-coccidialindex,ACI)分别是96、165.5、177、133.5、162.5。【结论】玉屏风加减煎剂对人工感染柔嫩艾美耳球虫德化黑鸡具有更好抗炎、抗氧化、提高免疫功能的免疫调节作用,并相应具有更好的抗球虫效果,且以玉屏风加减低剂量组(YL)抗球虫效果最好。 展开更多
关键词 玉屏风加减煎剂 德化黑鸡 柔嫩艾美耳球虫 免疫调节 抗球虫指数
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