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The Pedagogic Capacity of Architecture the Macro Project University Citadel—University of Atlántico Barranquilla—Colombia
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作者 Carlos Bell Lemus Mayra Alejandra Rivero Bueno 《Open Journal of Civil Engineering》 2018年第2期129-141,共13页
Urban agenda nowadays puts pedestrians as the axis of urban design, and pedestrians are the most important thing in the city. The architect takes that idea and applies it in the project, and he focuses on prioritizing... Urban agenda nowadays puts pedestrians as the axis of urban design, and pedestrians are the most important thing in the city. The architect takes that idea and applies it in the project, and he focuses on prioritizing the pedestrian over the cars. Public spaces filled with green zones are a main element, water treatment is a design determinant, buildings use natural illumination as much as possible and culture and arts are reinforced through new scenarios. 展开更多
关键词 UNIVERSITY PROJECT Urban Design PEDESTRIAN Public ARCHITECTURE
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Effects of loadinge-unloading and wettinge-drying cycles on geomechanical behaviors of mudrocks in the Colombian Andes 被引量:10
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作者 Mario Camilo Torres-Suarez Adolfo Alarcon-Guzman Rafael Berdugo-De Moya 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2014年第3期257-268,共12页
The mudrocks in the Colombian Andes, particularly those exhibiting low cementation (bonding), are susceptible to degradation when the environmental conditions change, which are challenging issues for engineering wor... The mudrocks in the Colombian Andes, particularly those exhibiting low cementation (bonding), are susceptible to degradation when the environmental conditions change, which are challenging issues for engineering works. In this paper, the changes in physico-mechanical properties of mudrocks were moni- tored in laboratory, and some influential factors on the mechanical competence of geomaterials were studied. The geotechnical characteristics and experimental designs were developed from physical, chem- ical, mechanical and compositional points of view. In the tests, the techniques such as vapor equilibrium technique (VET) were employed to apply wetting-drying cycles and to control relative humidity (suction- controlled) and loading-unloading cycles through ultrasonic wave velocities technique. The results show that the main failure mechanisms for the laminated mudrocks start on the microscopic scale by fissures coalescence, exhibiting physico-chemical degradation as well; the global geomechanical behavior presents a state between a ductile, like rock, and a fragile, like soil. The obtained results can provide engineering values according to monitoring laboratory set, when compared with in situ conditions. 展开更多
关键词 MudrocksDegradation processesSuction changesStress-strain behaviorVapor equilibrium technique (VET)
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Association of swine influenza H1N1 pandemic virus(SIV-H1N1p) with porcine respiratory disease complex in sows from commercial pig farms in Colombia 被引量:1
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作者 Luisa Fernanda Mancipe Jiménez Gloria Ramírez Nieto +1 位作者 Victor Vera Alfonso Jairo Jaime Correa 《Virologica Sinica》 SCIE CAS CSCD 2014年第4期242-249,共8页
Porcine respiratory disease complex(PRDC) is a serious health problem that mainly affects growing and finishing pigs. PRDC is caused by a combination of viral and bacterial agents, such as porcine reproductive and res... Porcine respiratory disease complex(PRDC) is a serious health problem that mainly affects growing and finishing pigs. PRDC is caused by a combination of viral and bacterial agents, such as porcine reproductive and respiratory syndrome virus(PRRSV), swine influenza virus(SIV), Mycoplasma hyopneumoniae(Myh), Actinobacillus pleuropneumoniae(APP), Pasteurella multocida and Porcine circovirus 2(PCV2). To characterize the specific role of swine influenza virus in PRDC presentation in Colombia, 11 farms from three major production regions in Colombia were examined in this study. Nasal swabs, bronchial lavage and lung tissue samples were obtained from animals displaying symptoms compatible with SIV. Isolation of SIV was performed in 9-day embryonated chicken eggs or Madin-Darby Canine Kidney(MDCK) cells. Positive isolates, identified via the hemagglutination inhibition test, were further analyzed using PCR. Overall, 7 of the 11 farms were positive for SIV. Notably, sequencing of the gene encoding the hemagglutinin(HA) protein led to grouping of strains into circulating viruses identified during the human outbreak of 2009, classified as pandemic H1N1-2009. Serum samples from 198 gilts and multiparous sows between 2008 and 2009 were obtained to determine antibody presence of APP, Myh, PCV2 and PRRSV in both SIV-H1N1p-negative and-positive farms, but higher levels were recorded for SIV-H1N1p-positive farms. Odds ratio(OR) and P values revealed statistically significant differences(p<0.05) in PRDC presentation in gilts and multiparous sows of farms positive for SIV-H1N1 p. Our findings indicate that positive farms have increased risk of PRDC presentation, in particular, PCV2, APP and Myh. 展开更多
关键词 猪呼吸道疾病综合征 猪流感病毒 经产母猪 哥伦比亚 商品猪场 猪繁殖与呼吸综合征病毒 胸膜肺炎放线杆菌 支气管肺泡灌洗液
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Geochemistry of heavy metals in soils of the Bogota River Basin, Colombia
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作者 Gloria Prieto Luz M. Gonzalez 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期63-63,共1页
关键词 环境地球化学 环境污染 元素 重金属 土壤
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Headwaters Deforestation for Cattle Pastures in the Andes of Colombia and Its Implications for Soils Properties and Hydrological Dynamic
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作者 Guillermo Vásquez-Velásquez 《Open Journal of Forestry》 2016年第5期337-347,共11页
Deforestation of headwater in the Andes of Colombia is a historical process that has its origins in pre-Hispanic communities and in nineteenth and twentieth centuries, intensified by settlers and farmers. These lands ... Deforestation of headwater in the Andes of Colombia is a historical process that has its origins in pre-Hispanic communities and in nineteenth and twentieth centuries, intensified by settlers and farmers. These lands have been intended mainly to pasture cattle. Soil compaction, caused by the trampling of cattle, was evaluated in soils derived from volcanic ash (Andisols), with reference to values found for variables in undisturbed natural forests in the same region. The compared parameters were bulk density (Db), total porosity (α), soil resistance to penetration (Rp) and pore size distribution, analyzed by water retention curves (WRC). The grazed soils had significant differences with respect to the natural forest reference values: Db was 53.7% higher, α was reduced by 11.0% and Rp in the first 7.5 cm of the top soil was more than double, with an average increase of 275.2 to 527.2 kPa. The analysis indicated that compacted soils had relatively uniform reduction in distribution of macro, meso and micropores. It was concluded that deforestation followed by pasture land destination in steep headwaters generates significant compaction processes that can affect the infiltration, percolation and soil water storage, which would have important hydrological implications: augmentation of surface runoff and soil erosion, decreased the base flow and increased direct runoff. For this reasons, it is considered that forest restoration of headwaters is important for the maintenance of hydrological functions of large river systems. 展开更多
关键词 Forest Influences DEFORESTATION Soil Compaction HEADWATERS
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Nutritional Situation of Rural Communities in Narino,Colombia 2013
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作者 Sara Eloísa Del Castillo Matamoros Teresa Mosquera Vásquez +1 位作者 Eliana Lorena Suárez Higuera Ana Patricia Heredia Vargas 《Food and Nutrition Sciences》 2014年第15期1521-1528,共8页
Objective: To evaluate the nutritional situation by anthropometry of the rural families population aged 0 to 64 years in the municipalities of Pasto, Túquerres, Guachucal, Cumbal and Cuaspud in the Nari?o Departm... Objective: To evaluate the nutritional situation by anthropometry of the rural families population aged 0 to 64 years in the municipalities of Pasto, Túquerres, Guachucal, Cumbal and Cuaspud in the Nari?o Department (Colombia). Materials and Methods: As part of the research “Improving potato production as a food security contribution of native communities in Nari&#241;o, Colombia”, aged October and December in 2013, an initial diagnosis of the food security situation in farmer families was conducted, through direct visits to the households selected in the sample, where in the household members, after standardization of field team, the anthropometric measures of weight and height were taken, using electronic scales, infantometers and stadiometers. Conclusions: A significant stunting was reported in children up to 7 years. In children aged 0 - 5 years group and children aged 5 - 17 years group, the results exceed by more than double the department data (according to National Survey of the Nutritional Situation in Colombia ENSIN 2010), and almost three times the national data. The underweight was generally low in all the analysed groups, although concerned the significant overweight percentage. In children aged 0 - 5 years group, the overweight data (above 2 SD) exceeded twice the department and national data according to the ENSIN 2010, although in the children aged 5 - 17 years group, the overweight and obesity was lower than the departmental and national data. In adults, the results reported that one of each two people in the range of 18 to 64 years in the five municipalities had excess weight (overweight or obesity) which was similar data respected to the department and national data. Additionally, it was noted that 18% of households were found among adults with overweight, and simultaneously, children with stunting, this situation has been called double burden of malnutrition and this is an aspect that must be analysed to identify intervention strategies. 展开更多
关键词 Nutritional Situation ANTHROPOMETRY STUNTING Excess Weight Narino’s Rural Families
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A study of fire propagation in coal seam with numerical simulation of heat transfer and chemical reaction rate in mining field 被引量:10
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作者 Moisés Oswaldo Bustamante Rúa Alan José Daza Aragón Pablo Bustamante Baena 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第6期873-879,共7页
Spontaneous combustion of coal is a problem that affects the mining operation and generates environ-mental,economic,social and geotechnical impacts.This phenomenon has been divided into two pro-cesses:ignition and pro... Spontaneous combustion of coal is a problem that affects the mining operation and generates environ-mental,economic,social and geotechnical impacts.This phenomenon has been divided into two pro-cesses:ignition and propagation.Fire propagation develops in coal seams because of a set of factors such as direction and wind speed,fracturing and temperature.In this work,heat transfer and chemical kinetics are studied from conservation equations of energy and species,respectively,using the software COMSOL Multiphysics to simulate the propagation of fires in coal seams.Two possible scenarios were analyzed that usually occur in the walls of the coal seams,such as fire focus and fire complete screens.It was found that the propagation kinetics of the fire changes depending on the temperature,the fractur-ing of rock mass and the area of fire influence.For temperature values lower than 300℃,there is con-sumption around 250 cm^3/h,values around 700℃,the consumption is 1500 cm^3/h,and for fires of 1200℃ have values of 3000 cm^3/h.Depending on the speed of propagation can vary from 4 to 17cm/day,considering on the level and fracturing of the final wall of the open pit. 展开更多
关键词 SPONTANEOUS COMBUSTION of COAL Open PIT mines Simulation Heat transfer Chemical reaction COMSOL
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Molecular and in vitro Characterization of Field Isolates of Bovine Herpesvirus-1 被引量:4
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作者 Julian Ruiz-Saenz Jairo Jaime +1 位作者 Gloria Ramirez Victor Vera 《Virologica Sinica》 SCIE CAS CSCD 2012年第1期26-37,共12页
Bovine Herpesvirus-1 (BoHV-1) is distributed worldwide and is a major pathogen in cattle, being the causal agent of a variety of clinical syndromes. The aim of this study was to isolate and to characterize (molecular ... Bovine Herpesvirus-1 (BoHV-1) is distributed worldwide and is a major pathogen in cattle, being the causal agent of a variety of clinical syndromes. The aim of this study was to isolate and to characterize (molecular and biological characterization) BoHV-1 from 29 immunosuppressed animals. It was possible to obtain 18 isolates, each from a different animal, such as from the respiratory and reproductive tracts. In some cases the cytopathic effect was visible 12 hours post-inoculation, and became characteristic after 36-48 hours. Biological characteristics were evaluated and compared with Iowa and Colorado-1 reference strains, and differences were found in plaque size, virus titer measured by TCID50 and PFU/mL, and one step virus curves. These results showed that some isolates had a highly virulent-like behavior in vitro, compared to the reference strains, with shorter eclipse periods, faster release of virus into the supernatants, and higher burst size and viral titer. There were no differences in glycoprotein expression of BoHV-1 isolates, measured by Western blot on monolayers. Moreover, using restriction endonucleases analysis, most of the viruses were confirmed as BoHV-1.1 and just one of them was confirmed as BoHV-1.2a subtype. These findings suggest that some wild-type BoHV-1 isolates could be useful as seeds to develop new monovalent vaccines. 展开更多
关键词 分子生物学特性 牛疱疹病毒 表征 体外 WESTERN印迹 分离 细胞病变效应 TCID50
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An Inactivated Vaccine from a Field Strain of Bovine Herpesvirus-1(BoHV-1) has High Antigenic Mass and Induces Strong Efficacy in a Rabbit Model 被引量:2
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作者 Julian Ruiz-Sáenz Jairo Jaime Victor Vera 《Virologica Sinica》 SCIE CAS CSCD 2013年第1期36-42,共7页
Bovine Herpesvirus-1 (BoHV-1) is a DNA virus belonging to the family Herpesviridae, subfamily Alfaherpesvirinae; it is a worldwide pathogen, causing serious economic losses in livestock. In Colombia there have been mu... Bovine Herpesvirus-1 (BoHV-1) is a DNA virus belonging to the family Herpesviridae, subfamily Alfaherpesvirinae; it is a worldwide pathogen, causing serious economic losses in livestock. In Colombia there have been multiple isolates of BoHV-1 that have been subjected to molecular characterization, classifying most of the country isolates as BoHV-1.1. In the present study we developed and evaluated an ethyleneimine binary inactivated isolate from the native BoHV-1 strain (Córdoba-2) in a rabbit model of vaccination and infection. The vaccine was evaluated in two phases, one of immunogenicity with vaccination and a booster after 21 days, and an evaluation phase of protection against challenge with a highly virulent reference strain. The results demonstrate optimum serum-conversion, with protective neutralizing antibody titers 28 days post vaccination and optimal protection against challenge with the reference strain with decreased clinical signs of infection, protection against the onset of fever and decrease of virus excretion post challenge. In conclusion, our results show the enormous potential that an immunogenic inactivated vaccine has produced from the native BoHV-1.1 strain, which produces a high antigen mass to the vaccine to induce optimal immunity and protection, and it is a strong candidate for evaluation and possible future use in different cattle populations. 展开更多
关键词 牛疱疹病毒 灭活疫苗 抗原 诱导 模型 疗效 疫苗接种
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Microencapsulation of Banana Passion Fruit (<i>Passiflora tripartita Var. Mollissima</i>): A New Alternative as a Natural Additive as Antioxidant 被引量:2
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作者 Maritza Gil Ana Restrepo +2 位作者 Leonidas Millán Luz Alzate Benjamín Rojano 《Food and Nutrition Sciences》 2014年第8期671-682,共12页
Banana passion fruit (P. tripartita var. Mollissima) is one of the most promising tropical fruits giving its antioxidant activity (AOA) to replace synthetic additives. Despite this property, there are no studies about... Banana passion fruit (P. tripartita var. Mollissima) is one of the most promising tropical fruits giving its antioxidant activity (AOA) to replace synthetic additives. Despite this property, there are no studies about the metabolites responsible for its biological function or proposals for the application of technologies, such as microencapsulation by spray drying, to improve its properties and ease its incorporation in several food matrices. The aim of this study is to microencapsulate the pulp of banana passion fruit with several mixtures of encapsulants and identify which one of these mixtures is better to preserve its AOA. The antioxidant activity values for the banana passion fruit pulp were as follows: DPPH: 6630.2 ± 91 μMtrolox/100g;ABTS: 18764.3 ± 270.4 μMtrolox/100g;FRAP: 1703.6± 938.2 mgAA/100g, ORAC: 8105.4 ± 424.2 μmol TEAC/100g of sample;Total phenols: 8862.2 ± 451.4 gallic ac. mg/100g. The concentrations of the bioactive compounds expressed in mg of gallic acid per 100 g of the pulp on a dry base were 13.9 ± 0.004;5.9 ± 0.001 and 126.3 ± 0.004 for caffeic, p-coumaric and ferulic acids, respectively. The best shelf-life followed by ABTS in eight assays was between 28.8 and 31.5 weeks using maltodextrin and modified starch, MD:MS (1/4:3/4) and MD:MS (0:1), respectively. In conclusion, ABTS is the best method to measure the AOA in banana passion fruit because it correlated with the phenolic compounds better than DPPH and FRAP methods. Additionally, two options were found to protect the AOA and to extent the shelf-life of the passion fruit by spray-drying, with mixtures of encapsulants widely used in the food industry. 展开更多
关键词 PASSIFLORA tripartite ABTS MALTODEXTRIN MICROENCAPSULATION Phenolic Compound
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NPV risk simulation of an open pit gold mine project under the O'Hara cost model by using Gas 被引量:1
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作者 Franco-Sepulveda Giovanni Campuzano Carlos Pineda Cindy 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第3期557-565,共9页
This paper analyzes an open pit gold mine project based on the O'Hara cost model. Hypothetical data is proposed based on different authors that have studied open pit gold projects, and variations are proposed acco... This paper analyzes an open pit gold mine project based on the O'Hara cost model. Hypothetical data is proposed based on different authors that have studied open pit gold projects, and variations are proposed according to the probability distributions associated to key variables affecting the NPV, like production level, ore grade, price of ore, and others, so as to see what if, in a gold open pit mine project of 3000 metric tons per day of ore. Two case scenarios were analyzed to simulate the NPV, one where there is low certainty data available, and the other where the information available is of high certainty. Results based on genetic algorithm metaheuristic simulations, which combine basically Montecarlo simulations provided by the Palisade Risk software, the O'Hara cost model, net smelter return and financial analysis tools offered by Excel are reported, in order to determine to which variables of the project is more sensitive the NPV. 展开更多
关键词 Genetic algorithms(GAs) O’Hara cost model Montecarlo simulation Open pit gold mine NPV risk analysis
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Bacterial extracts and bioformulates as a promising control of fruit body rot and root rot in avocado cv. Hass 被引量:1
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作者 David GRANADA Lorena LÓPEZ-LUJAN +4 位作者 Sara RAMIREZ-RESTREPO Juan MORALES Carlos PELÁEZ-JARAMILLO Galdino ANDRADE Juan Carlos BEDOYA-PEREZ 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第3期748-758,共11页
At least 20-40% of annual losses of avocado crops are caused by pathogenic fungi.The chemical treatments of these diseases are inefficient,cause environmental pollution and are increasingly restricted by international... At least 20-40% of annual losses of avocado crops are caused by pathogenic fungi.The chemical treatments of these diseases are inefficient,cause environmental pollution and are increasingly restricted by international laws.This work aimed to assess the biocontrol capacity of a bacterial extract to protect avocado fruits and plants from pathogen infections.Extracts from the bacterial isolate Serratia sp.ARP5.1 were obtained from liquid fermentations in a biorreactor.A body rot postharvest infection model with Colletotrichum gloeosporioides on fruits was developed.Moreover,packaging conditions were simulated using the bacterial extract and the commercial fungicide prochloraz as a positive control.Additionally,seedlings infections with Phytophthora cinnamomi were performed on two types of avocado(West Indian race and cv.Hass).The Area Under Disease Progress Curve(AUDPC) was recorded using the bacterial extract and a commercial product with fosetyl-aluminium as treatments.The bacterial extract significantly reduced infections by C.gloeosporioides on injured avocado fruits at 31.1 μg mL^-1.Intact fruits were also protected against body rot infections at the same concentration and showed no significant differences with the commercial fungicide.On the other hand,AUDPC in the seedlings was significantly reduced with the extract treatment at 3 μg mL^-1 compared to the control.However,a possible phytotoxicity effect of the extract was evidenced in the seedlings and confirmed by pathogen recovery and tests on Raphanus sativus seedlings.Finally,formulations of the extracts(emulsion and emulsifiable concentrate) were prepared,and bioactive stability was assessed for 8 wk.The emulsion formulates demonstrated very stable bioactivity against P.cinnamomi.The extract and the emulsion formulate showed promising results for the control of avocado pathogens.New bioproducts based on this type of active principles could be developed for the benefit of avocado industry. 展开更多
关键词 Colletotrichum gloeosporioides Phytophthora cinnamomi Serratia sp. antagonistic microbes secondary metabolites BIOFUNGICIDE
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Modelling the Spatial Distribution of Arsenic in Water and Its Correlation with Public Health, Central Indus Basin, Pakistan 被引量:1
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作者 Yawar Hussain Adil Dilawar +4 位作者 Sadia Fida Ullah Gulraiz Akhter Hernan Martinez-Carvajal Muhammad Babar Hussain Abdul Qayyum Aslam 《Journal of Geoscience and Environment Protection》 2016年第2期18-25,共8页
Like India, Bangladesh and China, Pakistan also has some regions where concentration of Arsenic in water has crossed the WHO safe drinking water limits, 10 ppb. Presence of Arsenic in drinking water is causing serious... Like India, Bangladesh and China, Pakistan also has some regions where concentration of Arsenic in water has crossed the WHO safe drinking water limits, 10 ppb. Presence of Arsenic in drinking water is causing serious human health issues for the local residents of Sindh and southern Punjab, which needs serious attention. The present study is focused on the spatial distribution of Arsenic in groundwater and its relationship with the major reported human diseases at settlement level of District Layyah. Data collection is done by taking water samples from hand pumps and health issues reported at the local health care centers adjoining to that sampling pump. The spatial distribution of Arsenic concentration in groundwater is done by using Inversion Distance Weight (IDW) technique. Arsenic Risk Index (ARI) is developed based of WHO health standards, and then used to divide study area into two Arsenic Risk Zones as no risk and high risk with As values less or equal to 10 ng·ml<sup>-1</sup> and greater than 10 ng·ml<sup>-1</sup>, respectively . In the final step these zones were correlated with the diseases at village level. The results show that, Arsenic is high near the Indus River and it decreases in central and eastern parts towards Chenab River. Same trend of Indo-Chenab Arsenic gradient is followed by skin diseases among the people especially, in tehsil Layyah and tehsil Koror. It is concluded that high Arsenic amount in water and skin diseases are highly dependent on the recharge from Indus River. 展开更多
关键词 ARSENIC GIS Human Health IDW Indus Basin Layyah
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Entropy Corrections for a Charged Black Hole of String Theory
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作者 Alexis Larraaga 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第1期72-74,共3页
我们学习控告的 GibbonsMaedaGarfinkleHorowitzStrominger (GMGHS ) 的熵黑洞,从出现在的有效行动发源绳理论低精力,在半古典作品近似以外。为三个变量把准确 differentials 的性质用于我们导出的第一法律热力学量修正到黑洞的熵。带... 我们学习控告的 GibbonsMaedaGarfinkleHorowitzStrominger (GMGHS ) 的熵黑洞,从出现在的有效行动发源绳理论低精力,在半古典作品近似以外。为三个变量把准确 differentials 的性质用于我们导出的第一法律热力学量修正到黑洞的熵。带(对数) 并且到区域法律的非领先的修正被获得。 展开更多
关键词 带电黑洞 黑洞熵 弦理论 更正 热力学第一定律 半经典近似 低能量
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Statistical analysis to establish an ignition scenario based on extrinsic and intrinsic variables of coal seams that affect spontaneous combustion
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作者 M.O.Bustamante Rúa A.J.Daza Aragón +1 位作者 P.Bustamante Baena J.D.Osorio Botero 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第5期731-737,共7页
Spontaneous combustion of coal seams in open pit mines is a problem that occurs in coal mines around the world.Theories have been developed that express several factors which generate self-heating in the coal and favo... Spontaneous combustion of coal seams in open pit mines is a problem that occurs in coal mines around the world.Theories have been developed that express several factors which generate self-heating in the coal and favor combustion.The synergy of these factors contributes to the increase in the temperature of oxidation reactions,facilitating the culmination of the activation energy of the system,in which the ignition develops and the reaction is spontaneous.Currently,the incidence of each variable’s susceptibility to coal combustion is unknown,so in this work a methodology was developed to determine statistically which of the variables has the greatest contribution in the phenomenon.Descriptive statistics,atypical values detection,principal component determination,cluster analysis,and logistic regression were used to determine how many indicator variables are necessary to describe susceptibility to coal combustion.For the analysis,21,000 data from different seams of two open-pit coal mines in endwalls and abandoned pits were processed with consideration given to extrinsic and intrinsic factors.Seam temperature,atmospheric pressure,wind speed,oxygen,methane,height,ash,volatile matter,heat power,vitrinite,liptinite and the Hardgrove Index are the most influential variables in the phenomenon. 展开更多
关键词 Coal fire SELF-IGNITION Statistics analysis Open PIT mines SPONTANEOUS combustion
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Predictive models of drought tolerance indices based on physiological,morphological and biochemical markers for the selection of cotton(Gossypium hirsutum L.)varieties
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作者 Yeison M QUEVEDO Liz P MORENO Eduardo BARRAGAN 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第5期1310-1320,共11页
The use of tolerant crop varieties is a strategy that mitigates the water deficit effect in a sustainable way.The generation of these varieties is more efficient when variables associated with this tolerance have been... The use of tolerant crop varieties is a strategy that mitigates the water deficit effect in a sustainable way.The generation of these varieties is more efficient when variables associated with this tolerance have been identified,since they can facilitate the breeding processes.This study aimed to establish the relationships between water deficit tolerance of four cotton varieties(Nevada-123,Oasis-129,Guatapuri,and Festivalle)and morphological variables(monopodial branches,boll weight,root/shoot ratio,and leaf and root dry matter),physiological variables(relative water content,net photosynthesis,stomatal conductance,electron transport rate,photochemical quenching,photochemical efficiency of PSII,chlorophyll a/b ratio(Chl a/b),C^(12)/C^(13)isotope ratio,and electrolyte leakage),and biochemical variables(contents of sugars,proline,carotenoids,and malondialdehyde).Furthermore,calibrated predictive models of the drought tolerance indices were developed based on the key variables identified.For this purpose,a pot experiment was established where plants were subjected to a moderate or severe water deficit during the blooming stage for 12 days.The stress tolerance index(STI)and mean productivity(MP)were calculated.For the evaluated variables,the differences between well-watered and water deficit plants(Δ)were calculated and ANOVA,partial least squares,Pearson’s correlation,and multiple linear regression analyzes were performed.A model was generated that explained 95% of the STI and was composed of Δmalondialdehyde,Δproline,and Δboll weight.For MP,the model was comprised of Δstomatal conductance,Δroot/shoot ratio,and ΔChl a/b,and explained 89% of the MP.The analysis of the assessed variables allowed the identification of key variables and the development of calibrated predictive models that can be used in screening to obtain cotton varieties with different levels of water deficit tolerance. 展开更多
关键词 drought tolerance tolerance index PROLINE CHLOROPHYLL stomatal conductance MALONDIALDEHYDE yield multivariate analysis
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SINGULAR LIMITS FOR INHOMOGENEOUS EQUATIONS OF ELASTICITY
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作者 陆云光 Christian Klingenberg 《Acta Mathematica Scientia》 SCIE CSCD 2009年第3期645-649,共5页
Based on the framework introduced in [4] or [5], the singular limits of stiff relaxation and dominant diffusion for the Cauchy problem of inhomogeneous equations of elasticity is studied. We are able to reach equilibr... Based on the framework introduced in [4] or [5], the singular limits of stiff relaxation and dominant diffusion for the Cauchy problem of inhomogeneous equations of elasticity is studied. We are able to reach equilibrium even though the nonlinear stress term is not strictly increasing. 展开更多
关键词 relaxation limit equations of elasticity compensated compactness invariantregions theory
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Simulation of Biogas Production from Solid Organic Wastes
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作者 Ignacio Contreras-Andrade Jonathan Parra-Santiago Carlos Alberto Guerrero-Fajardo 《Journal of Chemistry and Chemical Engineering》 2015年第2期107-112,共6页
关键词 燃料生产 有机废弃物 沼气 微分方程模型 保留时间 仿真 固体 替代燃料
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Spectrophotometric Determination of the pKa, Isosbestic Point and Equation of Absorbance vs. pH for a Universal pH Indicator
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作者 L. E. Vidal Salgado C. Vargas-Hernández 《American Journal of Analytical Chemistry》 2014年第17期1290-1301,共12页
The pKa and the isosbestic point of the universal pH indicator Carlo Ebra 1-11 (catalog number 45712) were determined using UV-Vis spectrophotometry. Aqueous buffer solutions with pHs ranging from 3.83 to 10.85 were m... The pKa and the isosbestic point of the universal pH indicator Carlo Ebra 1-11 (catalog number 45712) were determined using UV-Vis spectrophotometry. Aqueous buffer solutions with pHs ranging from 3.83 to 10.85 were mixed. Four methods—two graphical and two mathematical— were used to estimate the acid dissociation constant (pKa) and isosbestic point using absorbance measurements. The equation for the dependence of the absorbance on pH at λ = 600 nm was obtained using calibration curves. The resulting average pKa of the four methods was 8.277 with a standard deviation of 0.1728. The results obtained using the mathematical methods were very similar, with a deviation of 0.0014;the average pKa determined using these methods was 8.263 ± 0.001. The literature contains no previous reports of the pKa of this indicator. The isosbestic point occurs at a wavelength of 494 nm, with an absorbance of 0.46. 展开更多
关键词 Design of BUFFERS SPECTROPHOTOMETRIC Titration Determination of PKA Isosbestic Point UNIVERSAL PH Indicator
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The implementation of the Acoustic Impedance for the Monitoring of Industrial Processes
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作者 Jovani Alberto Jimenez Builes Juan Jose Gonzalez Espana 《通讯和计算机(中英文版)》 2012年第12期1343-1350,共8页
关键词 声阻抗 工业生产过程 监控 无损检测技术 玻璃样品 机器人 超声波 丙烯酸
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