A field experiment was conducted in 2009 and 2010 growing seasons, to study the effect of foliar application of iron-chelated ＂Fe-EDTA＂ at concentration 0, 100 and 200 mg/L on the seasonal dynamic of mineral composi...A field experiment was conducted in 2009 and 2010 growing seasons, to study the effect of foliar application of iron-chelated ＂Fe-EDTA＂ at concentration 0, 100 and 200 mg/L on the seasonal dynamic of mineral composition of N, P, K, Fe and Zn in petioles and berries of Halwani Lebanon and Kamali grape cultivars, grown on a calcareous soil in Mosul region, Iraq. The results revealed that the foliar application of 200 mg Fe/L caused a significant increase of N, P, K, Fe and Zn concentrations in petioles and berries compared with the control for both seasons. Additionally, the N, P, K, Fe and Zn concentration in petioles were high at the beginning of the growth season, whereas, decrease towards in the end of the growth season in both cultivars and seasons. While the N, P, K, Fe and Zn in berry content was increased towards from berry set to veraison and ripening stage in both cultivars and seasons. So there are various element contents in the cultivars.展开更多
Generation, morphology, and distribution of authigenic minerals directly reflect sedimentary environment and material sources. Surface sediments were collected from the western Gulf of Thailand during 2011–2012, and ...Generation, morphology, and distribution of authigenic minerals directly reflect sedimentary environment and material sources. Surface sediments were collected from the western Gulf of Thailand during 2011–2012, and 159 samples were analyzed to determine detrital minerals. Authigenic minerals, including siderite, pyrite, and glauconite, are abundant whereas secondary minerals, such as chlorite and limonite, are distributed widely in the study area. Siderite has a maximum content of 19.98 g/kg and appears in three types from nearshore to continental shelf, showing the process of forming-maturity-oxidation. In this process, the Mn O content in siderite decreases, but FeOand Mg O content increase. Colorless or transparent siderite pellets are fresh grains generated within a short time and widely distributed throughout the region; high content appears in coastal area where river inputs are discharged. Translucent cemented double pellets appearing light yellow to red are mature grains; high content is observed in the central shelf. Red-brown opaque granular pellets are oxidized grains,which are concentrated in the eastern gulf. Pyrite is mostly distributed in the central continental shelf with an approximately north–south strip. Pyrite are mainly observed in foraminifera shell and distributed in clayey silt sediments, which is similar to that in the Yangtze River mouth and the Yellow Sea. The pyrite in the gulf is deduced from genetic types associated with sulfate reduction and organic matter decomposition. Majority of glauconite are granular with few laminar. Glauconite is concentrated in the northern and southern parts within the boundary of 9.5° to 10.5°N and is affected by river input diffusion. The distribution of glauconite is closely correlated with that of chlorite and plagioclase, indicating that glauconite is possibly derived from altered products of chlorite and plagioclase. The KO content of glauconite is low or absent, indicating its short formation time.展开更多
Gas hydrate(GH)is an unconventional resource estimated at 1000-120,000 trillion m^(3)worldwide.Research on GH is ongoing to determine its geological and flow characteristics for commercial produc-tion.After two large-...Gas hydrate(GH)is an unconventional resource estimated at 1000-120,000 trillion m^(3)worldwide.Research on GH is ongoing to determine its geological and flow characteristics for commercial produc-tion.After two large-scale drilling expeditions to study the GH-bearing zone in the Ulleung Basin,the mineral composition of 488 sediment samples was analyzed using X-ray diffraction(XRD).Because the analysis is costly and dependent on experts,a machine learning model was developed to predict the mineral composition using XRD intensity profiles as input data.However,the model’s performance was limited because of improper preprocessing of the intensity profile.Because preprocessing was applied to each feature,the intensity trend was not preserved even though this factor is the most important when analyzing mineral composition.In this study,the profile was preprocessed for each sample using min-max scaling because relative intensity is critical for mineral analysis.For 49 test data among the 488 data,the convolutional neural network(CNN)model improved the average absolute error and coefficient of determination by 41%and 46%,respectively,than those of CNN model with feature-based pre-processing.This study confirms that combining preprocessing for each sample with CNN is the most efficient approach for analyzing XRD data.The developed model can be used for the compositional analysis of sediment samples from the Ulleung Basin and the Korea Plateau.In addition,the overall procedure can be applied to any XRD data of sediments worldwide.展开更多
The mineral composition of the sinter affects the quality of cold-bonded briquettes(CBB),which are prepared from returned sinter fines and serve as a cleaner blast furnace charge.Pulverization rate,compressive strengt...The mineral composition of the sinter affects the quality of cold-bonded briquettes(CBB),which are prepared from returned sinter fines and serve as a cleaner blast furnace charge.Pulverization rate,compressive strength,reduction disintegration index(RDI)and compressive strength after reduction experiment were tested to analyze the experimental parameters of CBB under the influence of different basicities and sintering time.The results show that when the basicity of CBB is increased from 0.5 to 1.5,the pulverization rate increases,and performance indexes such as compressive strength,RDI,and compressive strength exhibit a decreasing trend.When the basicity is increased from 1.5 to 3.0,all the aforementioned performance indexes are improved.When the sintering time is extended from 0 to 8 h,the properties mentioned above are improved.The results of X-ray diffraction,microstructure,and thermodynamic calculations confirm that the hematite in the mineral composition of CBB tends to convert into calcium ferrite,which leads to the increased compressive strength of CBB.The reasonable basicity and sintering time during sinter preparation not only form the desired mineral composition but also improve the properties of the CBB.展开更多
Rock strength evaluation is critical in oil and gas exploration,but traditional methods,such as empirical formulas,laboratory tests,and numerical simulations,often struggle with accuracy,generalizability,and alignment...Rock strength evaluation is critical in oil and gas exploration,but traditional methods,such as empirical formulas,laboratory tests,and numerical simulations,often struggle with accuracy,generalizability,and alignment with field conditions.This study proposes the use of Random Forest and Transformer algorithms to predict rock strength from Elemental Capture Spectroscopy(ECS)logs.By utilizing the dry weight of minerals as input,the model predicts key mechanical properties,including Young's modulus,Poisson's ratio,bulk modulus,shear modulus,and uniaxial compressive strength.The findings demonstrate that mineral compositions,such as clay,quartz-feldspar-mica,carbonate,anhydrite,and pyrite,significantly influence rock strength.Specifically,clay content impacts Young's modulus,bulk modulus,and shear modulus,while quartz-feldspar-mica affects Poisson's ratio,and anhydrite is the primary factor influencing compressive strength.Positive correlations were observed between rock strength and the dry weight of anhydrite and carbonate minerals,while negative correlations emerged with clay,pyrite,and quartz-feldspar-mica.The Random Forest model outperformed the Transformer model in terms of predictive accuracy and computational efficiency.Its training time is only one three hundredth of the latter and its prediction time is just one tenth of the later,making it highly suitable for welllogging interpretation.Although the Transformer model was less computationally efficient,it exhibited strengths in predicting subsurface strength parameters,particularly in capturing spatial variations and forecasting these parameters across different spatial locations.This study introduces a novel AI-driven approach to rock strength evaluation,bridging the gap between mineral composition and mechanical properties,with significant implications for resource extraction and reservoir management.展开更多
Increasing K＋ adsorption can be an effective alternative in building an available K pool in soils to optimize crop recovery and minimize losses into the environment. We hypothesized that long-term fertilization might...Increasing K＋ adsorption can be an effective alternative in building an available K pool in soils to optimize crop recovery and minimize losses into the environment. We hypothesized that long-term fertilization might change K＋ adsorption because of changes in the chemical and mineralogical properties of a rice （Oryza sativa L.）. The aims of this study were （i） to determine clay minerals in paddy soil clay size fractions using X-ray diffraction methods and a numerical diagramdecomposition method; （ii） to measure K＋ adsorption isotherms before and after H202 oxidation of organic matter, and （iii） to investigate whether K＋ adsorption is correlated with changes in soil chemical and mineral properties. The 30-yr longterm fertilization treatments caused little change in soil organic C （SOC） but a large variation in soil mineral composition. The whole-clay fraction （〈5 Jam） corresponded more to the fertilization treatment than the fine-clay fraction （〈1 gin） in terms of percentage of illite peak area. The total percentage of vermiculite-chlorite peak area was significantly negatively correlated with the total percentage ofillite peak area in the 〈5 lam soil particles （R=-0.946, P〈0.0006）. Different fertilization treatments gave significantly different results in K＋ adsorption. The SOC oxidation test showed positive effects of SOC on K＋ adsorption at lower K＋ concentration （≤120 mg L-0 and negative effects at higher K＋ concentration （240 mg L-l）. The K＋ adsorption by soil clay minerals after SOC oxidization accounted for 60-158% of that by unoxidized soils, suggesting a more important role of soil minerals than SOC on K＋ adsorption. The K＋ adsorption potential was significantly correlated to the amount of poorly crystallized illite present （R--0.879, P=0.012）. The availability of adsorbed K＋ for plant growth needs further study.展开更多
The Xinjie layered intrusion in the Panxi region,SW China,hosts both Fe-Ti oxide and platinum-group element（PGE） sulfide mineralization.The intrusion can be divided,from the base upward,into UnitsⅠ,ⅡandⅢ,in terms...The Xinjie layered intrusion in the Panxi region,SW China,hosts both Fe-Ti oxide and platinum-group element（PGE） sulfide mineralization.The intrusion can be divided,from the base upward,into UnitsⅠ,ⅡandⅢ,in terms of mineral assemblages.UnitsⅠandⅡare mainly composed of wehrlite and clino-pyroxenite, whereas UnitⅢis mainly composed of gabbro.PGE sulfide-rich layers mainly occur in Unit I, whereas thick Fe-Ti oxide-rich layers mainly occur in UnitⅢ.An ilmenite-rich layer occurs at the top of UnitⅠ.Fe-Ti oxides include magnetite and ilmenite.Small amounts of cumulus and intercumulus magnetite occur in UnitsⅠandⅡ.Cumulus magnetite grains are commonly euhedral and enclosed within olivine and clinopyroxene.They have high Cr2O3 contents ranging from 6.02 to 22.5 wt.%,indicating that they are likely an early crystallized phase from magmas.Intercumulus magnetite that usually displays ilmenite exsolution occupies the interstices between cumulus olivine crystals and coexists with interstitial clinopyroxene and plagioclase.Intercumulus magnetite has Cr2O3 ranging from 1.65 to 6.18 wt.%, lower than cumulus magnetite.The intercumulus magnetite may have crystallized from the trapped liquid.Large amounts of magnetite in UnitⅢcontains Cr2O3（＆lt;0.28 wt.%） much lower than magnetite in UnitsⅠandⅡ.The magnetite in UnitⅢis proposed to be accumulated from a Fe-Ti-rich melt.The Fe-Ti-rich melt is estimated to contain 35.9 wt.%of SiO2,26.9 wt.%of FeOt,8.2 wt.%of TiO2,13.2 wt.%of CaO, 8.3 wt.%of MgO,5.5 wt.%of Al2O3 and 1.0 wt.%of P2O5.The composition is comparable with the Fe-rich melts in the Skaergaard and Sept Iles intrusions.Paired non-reactive microstructures,granophyre pockets and ilmenite-rich intergrowths,are representative of Si-rich melt and Fe-Ti-rich melt,and are the direct evidence for the existence of an immiscible Fe-Ti-rich melt that formed from an evolved ferro-basaltic magma.展开更多
This study investigated the correlations between mechanical properties and mineralogy of granite using the digital image processing(DIP) and discrete element method(DEM). The results showed that the X-ray diffraction(...This study investigated the correlations between mechanical properties and mineralogy of granite using the digital image processing(DIP) and discrete element method(DEM). The results showed that the X-ray diffraction(XRD)-based DIP method effectively analyzed the mineral composition contents and spatial distributions of granite. During the particle flow code(PFC2D) model calibration phase, the numerical simulation exhibited that the uniaxial compressive strength(UCS) value, elastic modulus(E), and failure pattern of the granite specimen in the UCS test were comparable to the experiment. By establishing 351 sets of numerical models and exploring the impacts of mineral composition on the mechanical properties of granite, it indicated that there was no negative correlation between quartz and feldspar for UCS, tensile strength(σ_(t)), and E. In contrast, mica had a significant negative correlation for UCS, σ_(t), and E. The presence of quartz increased the brittleness of granite, whereas the presence of mica and feldspar increased its ductility in UCS and direct tensile strength(DTS) tests. Varying contents of major mineral compositions in granite showed minor influence on the number of cracks in both UCS and DTS tests.展开更多
Steel slag had lower activity and much lower hydration rate than cement. Quicklime and iron tailings were designed as modification agent to adjust the composition and properties of high temperature steel slag. The res...Steel slag had lower activity and much lower hydration rate than cement. Quicklime and iron tailings were designed as modification agent to adjust the composition and properties of high temperature steel slag. The results show that quicklime as modifier can greatly increase the content of cementitious minerals in modified steel slag and also promote the decomposition of RO phases and transformation of MgO in RO phase to f-MgO. After high temper- ature modification with compound modifier of quicklime and iron tailings, steel slag shows the main mineral phases of C3S, C2F and MgFe2O4. The activity index of modified steel slag at 28 days reaches 95.5% when the steel slag is modified by 15% of the compound modifier with the ratio of quicklime to iron tailings equal to 2 ： 1 at 1 350 ℃. Mo- reover, the sample with the modified steel slag exhibits the dense structure of hydration paste and the main hydration products of C-S-H gels and Ca（OH）2 crystals.展开更多
The Jiuyishan complex massif,located in the northern section of the Nanling region,is a combination of five plutons,namely,the Xuehuading,Jinjiling,Pangxiemu,Shaziling and Xishan plutons.Whole-rock geochemistry,Iminer...The Jiuyishan complex massif,located in the northern section of the Nanling region,is a combination of five plutons,namely,the Xuehuading,Jinjiling,Pangxiemu,Shaziling and Xishan plutons.Whole-rock geochemistry,Imineral electron microprobe analysis,zircon U-Pb dating and Hf isotope analysis were carried out for the Jinjiling and Pangxiemu plutons.The zircon U-Pb dating yields weighted mean ages of 152.9±0.9 Ma for the Jinjiling pluton and 151.7±1.5 Ma for the Pangxiemu pluton,with a narrow gap between them.The Jinjiling and Pangxiemu plutons both have geochemical characteristics of high SiO2,Al2 O3,Na2 O,K2 O and low TiO2,MgO,CaO,P2 O5 contents,with intense depletions in Sr,Ba,Ti,Eu and enrichments in Ga,FeoOT and HFSE,and these characteristics reflect an A-type affinity.From the Jinjiling to the Pangxiemu plutons,the mineral composition of mica changes from lepidomelane to zinnwaldite,with increases in F,Li2 O and Rb2 O contents.The mineral composition of zircon changes from low Zr/Hf to high Zr/Hf,with increasing HfO2,P2 O5 and UO2+ThO2+Y2 O3 contents.The mineral compositions of feldspar indicate that the Pangxiemu pluton contains more alkali feldspar than the Jinjiling pluton.The whole-rock geochemistry and mineral compositions reveal a higher degree of differentiation for the Pangxiemu pluton.The nearly uniformεHf(t)indicates the same source region for the two plutons:both were derived from partial melting of the lower crust,with small contributions of mantle materials.In addition,higher F,lower Nb/Ta and Zr/Hf ratios in the Pangxiemu Pluton suggest a closer relationship with the rare metal mineralization than for the Jinjiling pluton.展开更多
The Lower Cretaceous Xiagou Formation contains the major source rocks for the crude oils discovered in the Qingxi Sag and the South Uplift in the Jiuquan Basin, northwestern China. The Xiagou Formation source rock was...The Lower Cretaceous Xiagou Formation contains the major source rocks for the crude oils discovered in the Qingxi Sag and the South Uplift in the Jiuquan Basin, northwestern China. The Xiagou Formation source rock was formed in a closed,anoxic, reducing, alkaline lacustrine environment with a high salinity. Its high content of brittle minerals is favorable for the fracturing of reservoirs in source rock formations in the Qingxi Sag. The Xiagou Formation contains a great number of fair to excellent source rocks, and their organic matter（OM） came chiefly from plankton/algae and high plants as well as possibly bacterial organisms. The Xiagou Formation source rocks mainly contain Type II OM and some Type III and Type I OM, with good oil-generating potential. The source rock maturity is mainly in the early-mature and mature stages, and its Rovalue corresponding to oil peak is about 0.8%, which is lower than classic oil peak Rovalue of 1.0%; therefore, a great deal of hydrocarbon was generated before the classic oil peak Ro= 1.0%. Mature source rock in the Xiagou Formation tends to be distributed in the older members and at a greater depth. There is a better exploration potential of tight oil in the deep Qingxi Sag.展开更多
Spectra are sensitive in detecting main minerals on the lunar surface from visible light to infrared light. Since spectral characteristics of minerals are closely related to their compositions and the maturity level o...Spectra are sensitive in detecting main minerals on the lunar surface from visible light to infrared light. Since spectral characteristics of minerals are closely related to their compositions and the maturity level of soil on the Moon, studying the compositions and distribution of elements and minerals on the lunar surface can help to understand the evolution of the Moon through remote sensing technology. The correlation between the spectral characteristics of Chang＇e-1 interference imaging spectrometry（IIM） reflectance images and the mineral contents of LSCC（Lunar Soil Characterization Consortium） lunar surface mineral samples was discussed and the spatial distributions of Fe O and Al_2O_3 contained in both pyroxene and plagioclase on LQ-4 were studied using the improved angle parameter method, MNF, and band ratio statistics. A comparison of the mapping results of the optical models by Lucey, Shkuractov and other researchers on Clementine and the gamma ray spectrometry data shows that the content error is within 0.6% for lunar mare areas and close to 1% for the highland areas. The tectonic framework on the lunar surface was also investigated. And based on integrated analysis of previous findings on topography of the lunar surface, Chang＇e LAM, CCD and LOLA images and the gravity anomalies data（Clementine GLGM-2）, the tectonic unit subdivision was established for LQ-4, the idea of subdividing the lunar tectonic units was proposed, and this will provide a good foundation for studying the lunar tectonic evolution.展开更多
Shale oil is one of the most promising alternative unconventional energies in the world,and Lucaogou Formation shows significant exploration potential,becoming the primary target in northwestern China.This paper compa...Shale oil is one of the most promising alternative unconventional energies in the world,and Lucaogou Formation shows significant exploration potential,becoming the primary target in northwestern China.This paper compared the mechanical properties of shale layered samples from oil layer and interlayer of Lucaogou Formation,using uniaxial compressive tests with real-time micro-CT scanning.After that,the mineral analysis was conducted on one cross-section of the fractured sample to analyze the influence of mineral composition and distribution on micro-crack propagation.Such research has rarely been reported before.The results showed the surface porosity and elastic modulus of oil-bearing samples is larger than that of the interlayer samples,while the uniaxial compressive strength is lower.Besides,when there is only one dominant mineral with a content greater than 60%,a main crack tends to form at this area;When there are 2~3 major minerals with a content of 10%-60%,a fractured zone with many fine micro-cracks is more likely to form here.Finally,the higher the Moh's hardness of the mineral,the more difficult it is for micro-cracks to develop through it.展开更多
Mechanical properties of shales are key parameters influencing hydrocarbon production – impacting borehole stability, hydraulic fracture extension and microscale variations in in situ stress. We use Ordovician shale(...Mechanical properties of shales are key parameters influencing hydrocarbon production – impacting borehole stability, hydraulic fracture extension and microscale variations in in situ stress. We use Ordovician shale(Sichuan Basin, China) as a type-example to characterize variations in mineral particle properties at microscale including particle morphology, form of contact and spatial distribution via mineral liberation analysis(MLA) and scanning electron microscopy(SEM). Deformation-based constitutive models are then built using finite element methods to define the impact of various architectures of fracture and mineral distributions at nanometer scale on the deformation characteristics at macroscale.Relative compositions of siliceous, calcareous and clay mineral particles are shown to be the key factors influencing brittleness. Shales with similar mineral composition show a spectrum of equivalent medium mechanical properties due to differing particle morphology and mineral heterogeneity. The predominance of small particles and/or point-point contacts are conducive to brittle failure, in general, and especially so when quartz-rich. Fracture morphology, length and extent of filling all influence shale deformability. High aspect-ratio fractures concentrate stress at fracture tips and are conducive to extension, as when part-filled by carbonate minerals. As fracture spacing increases, stress transfer between adjacent fractures weakens, stress concentrations are amplified and fracture extension is favored. The higher the fractal dimension of the fracture and heterogeneity of the host the more pervasive the fractures. Moreover, when fractures extend, their potential for intersection and interconnection contributes to a reduction in strength and the promotion of brittle failure. Thus, these results provide important theoretical insights into the role of heterogeneity on the deformability and strength of shale reservoirs with practical implications for their stimulation and in the recovery of hydrocarbons from them.展开更多
Based on the principle of ENV 196-4 ＂Methods of testing cement - Part 4 Quantitative determination of constituents or Chinese Standard GB/12960-2007 Quantitative measurement of mineral admixtures in cement, methods w...Based on the principle of ENV 196-4 ＂Methods of testing cement - Part 4 Quantitative determination of constituents or Chinese Standard GB/12960-2007 Quantitative measurement of mineral admixtures in cement, methods were developed for quantitative determination of fly ash, slag and limestone powder in fresh cement pastes, mortars and concretes. Limestone powder was determined using thermal analysis method. The residue content of fly ash on an 80um sieve, and silt contents of aggregate were also considered during the quantitative determination of mineral composition of quaternary cementitious system. With the developed methods, the deviations between the measured and the actual mineral contents of the constituent in the eemantitious material in fresh cement paste, mortar and concrete, were within 3%.展开更多
Objective: To investigate the proximate and mineral composition of the Piper retrofractum(P. retrofractum) vahl. Fruit and to evaluate its total alkaloids, phenol and flavonoid. Methods: The proximate composition of P...Objective: To investigate the proximate and mineral composition of the Piper retrofractum(P. retrofractum) vahl. Fruit and to evaluate its total alkaloids, phenol and flavonoid. Methods: The proximate composition of P. retrofractum fruit was ananlyzed using standard protocols according to Indonesian Standard and Association of Official Analytical Chemist. Meanwhile, mineral composition of the fruit was analyzed using inductively coupled plasma-mass spectrometry. Phytochemical screening and quantification were performed using standard protocols according to Harborn and spectrophotometric methods. Results: The results showed that P. retrofractum fruit contained carbohydrate(63.4%), crude protein(11.4%), total ash(4.29%), dietary fiber(28.8%) and total fat(2.97%). The fruit also contained calcium, copper, iron, magnesium, phosphor, potassium, sodium and zinc in different concentrations. Additionally, quinone, sterol, glycosides and alkaloid were detected in both n-hexane and ethyl acetate extracts. Moreover, tannin was presented also in ethylacetate and methanol extracts. Meanwhile, methanol extract contained sterol, glycosides, flavones, tannin and alkaloid. The results also revealed that methanol extract of the fruit contained highest phenol compared to other extract. Finally, small quantity of flavonoid(0.060 0%±0.000 2%) was observed. Conclusions: The overall results show that P. retrofractum contains potential nutritional and phytochemicals values, which support their function for pharmaceutical purposes.展开更多
Natural fractures are widely distributed in shale reservoirs.During the hydraulic fracturing process,frictional slip occurring on natural fractures can increase the reservoir permeability and is of great significance ...Natural fractures are widely distributed in shale reservoirs.During the hydraulic fracturing process,frictional slip occurring on natural fractures can increase the reservoir permeability and is of great significance to improve the efficiency of reservoir stimulation.Shale contains a large amount of clay and organic matter,and its frictional behavior is different from that of other previously studied lithologies.In this paper,the frictional behavior of shale is analyzed,and the results show that the frictional behavior is controlled by the content of clay and organic matter.As the content of clay and organic matter increases,the micro support type transforms from the particle support mode by hard quartz mineral to matrix support mode by plastic clay and organic matter.Accordingly,the shear strength and friction coefficient of shale both decrease,and the shear type transforms from brittle to plastic.When the content of clay and organic matter is low,the asperity of friction surfaces will break in a brittle manner and the wear degree of surfaces is low.Therefore,fractures are still featured by moderate apertures after friction.The lower the content of clay and organic matter is,the easier the asperity of crack surfaces supports themselves,and the higher the fracture residual permeability is.Thus,promoting shear slip is the main measure of reservoir stimulation.However,when the content of clay and organic matter is high,the remaining post-slip fracture aperture is small.It is difficult to increase reservoir permeability through the frictional slip of natural fractures,and in this situation,the proppant support efficiency needs to be improved.展开更多
Spices which are widely used in Southwest Nigeria have aroma, enhance taste of food and possess medicinal values. Proximate, mineral composition and phytochemical screening of ten randomly selected spices were carried...Spices which are widely used in Southwest Nigeria have aroma, enhance taste of food and possess medicinal values. Proximate, mineral composition and phytochemical screening of ten randomly selected spices were carried out. Recommended procedures were used for the analyses. Mineral composition was determined using flame photometer, colorimeter and （Atomic Absorption Spectrophotometer）. The proximate composition showed that protein was high at 12.04% in Zingiber officinale and low at 2.1% in Xylopia aethiopica. Ocimium gratissium contained high moisture content at 82.1%, while Tetrapleura tetraptera had the least value of 3.5%. High ash content was recorded in Ocimum gratissium at 13.68% and lowest 0.98% in Allium cepa. For carbohydrate, Allium cepa had the highest value of 78.36%, while Allium setiva had the least value of 19.48%. Mineral composition showed high value of calcium 712 mg/100g, magnesium 172.2 mg/100g, potassium 868.5 mg/100g, sodium 75.85 mg/100g, and manganese 95.38 mg/100g in Allium sativa, Xylopia aethiopica, Momodara myristica, Ocimum gratissimum, Tetrapleura tetraptera respectively. Aframomium meleghueta had high value of iron and zinc at 85 mg/100g and 97 mg/100g respectively and also high presence of alkaloids, glycosides, saponins and tarmis. High values of saponins and triterpenoids were observed in Zingiber officinale and Ocimum gratissimum respectively. This study showed that spices have greater use in medicine and as food supplement.展开更多
The expansion of hydroponics in many countries of the world in the last few decades may be ascribed to the ability of soilless growing systems to avoid various problems arising from the use of the soil. Cucumber （Cuc...The expansion of hydroponics in many countries of the world in the last few decades may be ascribed to the ability of soilless growing systems to avoid various problems arising from the use of the soil. Cucumber （Cucurnis sativus L.） and zucchini （Cucurbita pepo L.） plants were grown in closed-soilless culture under unheated-greenhouse conditions at the experimental farm of University of Tuscia, Central Italy to evaluate the effects of four substrates （rockwool, pumice, perlite, and cocofiber） on growth, yield and plant mineral composition. For both cultures, plants grown in cocofiber, perlite and pumice yielded more than those grown in rockwool. The better temperature regime in cocofiber, perlite and pumice was due to the greater thermal inertia compared to rockwool slabs. Thc concentration of N in zucchini and cucumber leaves was significantly higher in cocofiber, perlite and pumice in comparison to the rockwool treatment. The concentration of K was significantly affected by the substrate only for the zucchini squash with the highest value recorded on the organic substrate （cocofiber）, whereas the Ca concentration was significantly influenced by the growing media only for cucumber with the highest value observed on pumice. Finally, the lowest Mg concentration in leaf tissue was observed on plants grown with the rockwool substrate for both zucchini squash and cucumber. We can conclude that cocofiber, perlite and pumice are suitable for zucchini and cucumber production in closed soilless system, whereas the use of rockwool is more suitable for crops grown under heated greenhouse conditions.展开更多
Ferrimagnetic materials such as natural magnetite are used for practical applications because of their electronic, magnetic and catalytic properties in the degradation of organic compounds. In order to determine its p...Ferrimagnetic materials such as natural magnetite are used for practical applications because of their electronic, magnetic and catalytic properties in the degradation of organic compounds. In order to determine its physicochemical properties in relation to its catalytic activity, the natural magnetite of Ofoud Mount (Niger) is characterized by X-ray florescence (XRF), X-ray diffraction (DRX), specific surface area (BET) and Fourier transformed infrared (FTIR). The result shows an iron content of 97.09% and a specific surface area of 69.742 m<sup>2</sup>/g. The crystal structure of magnetite is cubic with lattice parameters <i>α</i> = <i>β</i> = <i>γ</i> = 90°, a (Å) = b (Å) = c (Å) = 8.3740. The results of this study suggest that the natural magnetite of Ofoud Mount can be used as iron source in various fields of science despite the presence of a few impurities that can improve its catalytic activity.展开更多
文摘A field experiment was conducted in 2009 and 2010 growing seasons, to study the effect of foliar application of iron-chelated ＂Fe-EDTA＂ at concentration 0, 100 and 200 mg/L on the seasonal dynamic of mineral composition of N, P, K, Fe and Zn in petioles and berries of Halwani Lebanon and Kamali grape cultivars, grown on a calcareous soil in Mosul region, Iraq. The results revealed that the foliar application of 200 mg Fe/L caused a significant increase of N, P, K, Fe and Zn concentrations in petioles and berries compared with the control for both seasons. Additionally, the N, P, K, Fe and Zn concentration in petioles were high at the beginning of the growth season, whereas, decrease towards in the end of the growth season in both cultivars and seasons. While the N, P, K, Fe and Zn in berry content was increased towards from berry set to veraison and ripening stage in both cultivars and seasons. So there are various element contents in the cultivars.
基金The National Programme on Global Change and Air-sea Interaction under contract No.GASI-02-SCS-CJ03China Geological Survey:Continental Shelf Drilling Program under contract No.GZH201100202China-Thailand Cooperation Project"Research on Vulnerability of Coastal Zones"
文摘Generation, morphology, and distribution of authigenic minerals directly reflect sedimentary environment and material sources. Surface sediments were collected from the western Gulf of Thailand during 2011–2012, and 159 samples were analyzed to determine detrital minerals. Authigenic minerals, including siderite, pyrite, and glauconite, are abundant whereas secondary minerals, such as chlorite and limonite, are distributed widely in the study area. Siderite has a maximum content of 19.98 g/kg and appears in three types from nearshore to continental shelf, showing the process of forming-maturity-oxidation. In this process, the Mn O content in siderite decreases, but FeOand Mg O content increase. Colorless or transparent siderite pellets are fresh grains generated within a short time and widely distributed throughout the region; high content appears in coastal area where river inputs are discharged. Translucent cemented double pellets appearing light yellow to red are mature grains; high content is observed in the central shelf. Red-brown opaque granular pellets are oxidized grains,which are concentrated in the eastern gulf. Pyrite is mostly distributed in the central continental shelf with an approximately north–south strip. Pyrite are mainly observed in foraminifera shell and distributed in clayey silt sediments, which is similar to that in the Yangtze River mouth and the Yellow Sea. The pyrite in the gulf is deduced from genetic types associated with sulfate reduction and organic matter decomposition. Majority of glauconite are granular with few laminar. Glauconite is concentrated in the northern and southern parts within the boundary of 9.5° to 10.5°N and is affected by river input diffusion. The distribution of glauconite is closely correlated with that of chlorite and plagioclase, indicating that glauconite is possibly derived from altered products of chlorite and plagioclase. The KO content of glauconite is low or absent, indicating its short formation time.
基金supported by the Gas Hydrate R&D Organization and the Korea Institute of Geoscience and Mineral Resources(KIGAM)(GP2021-010)supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.2021R1C1C1004460)Korea Institute of Energy Technology Evaluation and Planning(KETEP)grant funded by the Korean government(MOTIE)(20214000000500,Training Program of CCUS for Green Growth).
文摘Gas hydrate(GH)is an unconventional resource estimated at 1000-120,000 trillion m^(3)worldwide.Research on GH is ongoing to determine its geological and flow characteristics for commercial produc-tion.After two large-scale drilling expeditions to study the GH-bearing zone in the Ulleung Basin,the mineral composition of 488 sediment samples was analyzed using X-ray diffraction(XRD).Because the analysis is costly and dependent on experts,a machine learning model was developed to predict the mineral composition using XRD intensity profiles as input data.However,the model’s performance was limited because of improper preprocessing of the intensity profile.Because preprocessing was applied to each feature,the intensity trend was not preserved even though this factor is the most important when analyzing mineral composition.In this study,the profile was preprocessed for each sample using min-max scaling because relative intensity is critical for mineral analysis.For 49 test data among the 488 data,the convolutional neural network(CNN)model improved the average absolute error and coefficient of determination by 41%and 46%,respectively,than those of CNN model with feature-based pre-processing.This study confirms that combining preprocessing for each sample with CNN is the most efficient approach for analyzing XRD data.The developed model can be used for the compositional analysis of sediment samples from the Ulleung Basin and the Korea Plateau.In addition,the overall procedure can be applied to any XRD data of sediments worldwide.
基金supported by Distinguished Professor(Tracking Plan)of Oriental Scholars of Shanghai Universities(Grant No.GZ2020013)National 111 Project(The Program of Introducing Talents of Discipline to University)(Grant No.Dl7002)+1 种基金Independent Research Project of State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced Ferrometallurgy and Shanghai University(Grant No.SKLASS 2022-Z011)Additionally,the authors are appreciative of the funding from the Academy of Finland with Grant No.349833.
文摘The mineral composition of the sinter affects the quality of cold-bonded briquettes(CBB),which are prepared from returned sinter fines and serve as a cleaner blast furnace charge.Pulverization rate,compressive strength,reduction disintegration index(RDI)and compressive strength after reduction experiment were tested to analyze the experimental parameters of CBB under the influence of different basicities and sintering time.The results show that when the basicity of CBB is increased from 0.5 to 1.5,the pulverization rate increases,and performance indexes such as compressive strength,RDI,and compressive strength exhibit a decreasing trend.When the basicity is increased from 1.5 to 3.0,all the aforementioned performance indexes are improved.When the sintering time is extended from 0 to 8 h,the properties mentioned above are improved.The results of X-ray diffraction,microstructure,and thermodynamic calculations confirm that the hematite in the mineral composition of CBB tends to convert into calcium ferrite,which leads to the increased compressive strength of CBB.The reasonable basicity and sintering time during sinter preparation not only form the desired mineral composition but also improve the properties of the CBB.
基金funded by General Program of National Natural Science Foundation of China(No.52274016,52374016)the Foundation of State Key Laboratory of Petroleum Resources and Prospecting(PRE/DX-2402)。
文摘Rock strength evaluation is critical in oil and gas exploration,but traditional methods,such as empirical formulas,laboratory tests,and numerical simulations,often struggle with accuracy,generalizability,and alignment with field conditions.This study proposes the use of Random Forest and Transformer algorithms to predict rock strength from Elemental Capture Spectroscopy(ECS)logs.By utilizing the dry weight of minerals as input,the model predicts key mechanical properties,including Young's modulus,Poisson's ratio,bulk modulus,shear modulus,and uniaxial compressive strength.The findings demonstrate that mineral compositions,such as clay,quartz-feldspar-mica,carbonate,anhydrite,and pyrite,significantly influence rock strength.Specifically,clay content impacts Young's modulus,bulk modulus,and shear modulus,while quartz-feldspar-mica affects Poisson's ratio,and anhydrite is the primary factor influencing compressive strength.Positive correlations were observed between rock strength and the dry weight of anhydrite and carbonate minerals,while negative correlations emerged with clay,pyrite,and quartz-feldspar-mica.The Random Forest model outperformed the Transformer model in terms of predictive accuracy and computational efficiency.Its training time is only one three hundredth of the latter and its prediction time is just one tenth of the later,making it highly suitable for welllogging interpretation.Although the Transformer model was less computationally efficient,it exhibited strengths in predicting subsurface strength parameters,particularly in capturing spatial variations and forecasting these parameters across different spatial locations.This study introduces a novel AI-driven approach to rock strength evaluation,bridging the gap between mineral composition and mechanical properties,with significant implications for resource extraction and reservoir management.
基金funded by the the Public Service Sectors (Agriculture) Research Special Funds, China(201203013-06)supported in partial by the International Plant Nutrition Institute (IPNI ChinaProgram: Hunan-16)the Key Technologies R&D Program of China during the 12th Five-Year-Plan period(2012BAD05B05-3)
文摘Increasing K＋ adsorption can be an effective alternative in building an available K pool in soils to optimize crop recovery and minimize losses into the environment. We hypothesized that long-term fertilization might change K＋ adsorption because of changes in the chemical and mineralogical properties of a rice （Oryza sativa L.）. The aims of this study were （i） to determine clay minerals in paddy soil clay size fractions using X-ray diffraction methods and a numerical diagramdecomposition method; （ii） to measure K＋ adsorption isotherms before and after H202 oxidation of organic matter, and （iii） to investigate whether K＋ adsorption is correlated with changes in soil chemical and mineral properties. The 30-yr longterm fertilization treatments caused little change in soil organic C （SOC） but a large variation in soil mineral composition. The whole-clay fraction （〈5 Jam） corresponded more to the fertilization treatment than the fine-clay fraction （〈1 gin） in terms of percentage of illite peak area. The total percentage of vermiculite-chlorite peak area was significantly negatively correlated with the total percentage ofillite peak area in the 〈5 lam soil particles （R=-0.946, P〈0.0006）. Different fertilization treatments gave significantly different results in K＋ adsorption. The SOC oxidation test showed positive effects of SOC on K＋ adsorption at lower K＋ concentration （≤120 mg L-0 and negative effects at higher K＋ concentration （240 mg L-l）. The K＋ adsorption by soil clay minerals after SOC oxidization accounted for 60-158% of that by unoxidized soils, suggesting a more important role of soil minerals than SOC on K＋ adsorption. The K＋ adsorption potential was significantly correlated to the amount of poorly crystallized illite present （R--0.879, P=0.012）. The availability of adsorbed K＋ for plant growth needs further study.
基金supported by a National Program on Key Basic Research Project(973 Program,Grant No.2011CB808903)National Natural Science Foundation of China(Grant Nos.41073030 and 41121002)a 'CAS Hundred Talents' project under Chinese Academy of Sciences to CYW and a GIGCAS 135 project Y234041001
文摘The Xinjie layered intrusion in the Panxi region,SW China,hosts both Fe-Ti oxide and platinum-group element（PGE） sulfide mineralization.The intrusion can be divided,from the base upward,into UnitsⅠ,ⅡandⅢ,in terms of mineral assemblages.UnitsⅠandⅡare mainly composed of wehrlite and clino-pyroxenite, whereas UnitⅢis mainly composed of gabbro.PGE sulfide-rich layers mainly occur in Unit I, whereas thick Fe-Ti oxide-rich layers mainly occur in UnitⅢ.An ilmenite-rich layer occurs at the top of UnitⅠ.Fe-Ti oxides include magnetite and ilmenite.Small amounts of cumulus and intercumulus magnetite occur in UnitsⅠandⅡ.Cumulus magnetite grains are commonly euhedral and enclosed within olivine and clinopyroxene.They have high Cr2O3 contents ranging from 6.02 to 22.5 wt.%,indicating that they are likely an early crystallized phase from magmas.Intercumulus magnetite that usually displays ilmenite exsolution occupies the interstices between cumulus olivine crystals and coexists with interstitial clinopyroxene and plagioclase.Intercumulus magnetite has Cr2O3 ranging from 1.65 to 6.18 wt.%, lower than cumulus magnetite.The intercumulus magnetite may have crystallized from the trapped liquid.Large amounts of magnetite in UnitⅢcontains Cr2O3（＆lt;0.28 wt.%） much lower than magnetite in UnitsⅠandⅡ.The magnetite in UnitⅢis proposed to be accumulated from a Fe-Ti-rich melt.The Fe-Ti-rich melt is estimated to contain 35.9 wt.%of SiO2,26.9 wt.%of FeOt,8.2 wt.%of TiO2,13.2 wt.%of CaO, 8.3 wt.%of MgO,5.5 wt.%of Al2O3 and 1.0 wt.%of P2O5.The composition is comparable with the Fe-rich melts in the Skaergaard and Sept Iles intrusions.Paired non-reactive microstructures,granophyre pockets and ilmenite-rich intergrowths,are representative of Si-rich melt and Fe-Ti-rich melt,and are the direct evidence for the existence of an immiscible Fe-Ti-rich melt that formed from an evolved ferro-basaltic magma.
基金This research was supported by the Department of Mining Engineering at the University of Utah.In addition,the lead author wishes to acknowledge the financial support received from the Talent Introduction Project,part of the Elite Program of Shandong University of Science and Technology(No.0104060540171).
文摘This study investigated the correlations between mechanical properties and mineralogy of granite using the digital image processing(DIP) and discrete element method(DEM). The results showed that the X-ray diffraction(XRD)-based DIP method effectively analyzed the mineral composition contents and spatial distributions of granite. During the particle flow code(PFC2D) model calibration phase, the numerical simulation exhibited that the uniaxial compressive strength(UCS) value, elastic modulus(E), and failure pattern of the granite specimen in the UCS test were comparable to the experiment. By establishing 351 sets of numerical models and exploring the impacts of mineral composition on the mechanical properties of granite, it indicated that there was no negative correlation between quartz and feldspar for UCS, tensile strength(σ_(t)), and E. In contrast, mica had a significant negative correlation for UCS, σ_(t), and E. The presence of quartz increased the brittleness of granite, whereas the presence of mica and feldspar increased its ductility in UCS and direct tensile strength(DTS) tests. Varying contents of major mineral compositions in granite showed minor influence on the number of cracks in both UCS and DTS tests.
基金Sponsored by National Key-tech Research and Development Program of China(2011BAB03B05,2013BAC12B04)
文摘Steel slag had lower activity and much lower hydration rate than cement. Quicklime and iron tailings were designed as modification agent to adjust the composition and properties of high temperature steel slag. The results show that quicklime as modifier can greatly increase the content of cementitious minerals in modified steel slag and also promote the decomposition of RO phases and transformation of MgO in RO phase to f-MgO. After high temper- ature modification with compound modifier of quicklime and iron tailings, steel slag shows the main mineral phases of C3S, C2F and MgFe2O4. The activity index of modified steel slag at 28 days reaches 95.5% when the steel slag is modified by 15% of the compound modifier with the ratio of quicklime to iron tailings equal to 2 ： 1 at 1 350 ℃. Mo- reover, the sample with the modified steel slag exhibits the dense structure of hydration paste and the main hydration products of C-S-H gels and Ca（OH）2 crystals.
基金financially supported by the Key R&D Program of China(Grant No.2017YFC0602402)the Innovationdriven Plan of Central South University,China(Grant No.2015CX008)+2 种基金the China Postdoctoral Science Foundation(Grant No.2017M622597)Open Research Fund Program of Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring(Central South University),Ministry of Education(Grant No.2019YSJS23)the Natural Science Foundation of Hunan Province(Grant No.2017JJ3138)
文摘The Jiuyishan complex massif,located in the northern section of the Nanling region,is a combination of five plutons,namely,the Xuehuading,Jinjiling,Pangxiemu,Shaziling and Xishan plutons.Whole-rock geochemistry,Imineral electron microprobe analysis,zircon U-Pb dating and Hf isotope analysis were carried out for the Jinjiling and Pangxiemu plutons.The zircon U-Pb dating yields weighted mean ages of 152.9±0.9 Ma for the Jinjiling pluton and 151.7±1.5 Ma for the Pangxiemu pluton,with a narrow gap between them.The Jinjiling and Pangxiemu plutons both have geochemical characteristics of high SiO2,Al2 O3,Na2 O,K2 O and low TiO2,MgO,CaO,P2 O5 contents,with intense depletions in Sr,Ba,Ti,Eu and enrichments in Ga,FeoOT and HFSE,and these characteristics reflect an A-type affinity.From the Jinjiling to the Pangxiemu plutons,the mineral composition of mica changes from lepidomelane to zinnwaldite,with increases in F,Li2 O and Rb2 O contents.The mineral composition of zircon changes from low Zr/Hf to high Zr/Hf,with increasing HfO2,P2 O5 and UO2+ThO2+Y2 O3 contents.The mineral compositions of feldspar indicate that the Pangxiemu pluton contains more alkali feldspar than the Jinjiling pluton.The whole-rock geochemistry and mineral compositions reveal a higher degree of differentiation for the Pangxiemu pluton.The nearly uniformεHf(t)indicates the same source region for the two plutons:both were derived from partial melting of the lower crust,with small contributions of mantle materials.In addition,higher F,lower Nb/Ta and Zr/Hf ratios in the Pangxiemu Pluton suggest a closer relationship with the rare metal mineralization than for the Jinjiling pluton.
基金supported by the Fourth Petroleum Resource Evaluation Project of China (Grant No. 2013E050209)the National S&T Major Project of China (Grant No. 2012E330)
文摘The Lower Cretaceous Xiagou Formation contains the major source rocks for the crude oils discovered in the Qingxi Sag and the South Uplift in the Jiuquan Basin, northwestern China. The Xiagou Formation source rock was formed in a closed,anoxic, reducing, alkaline lacustrine environment with a high salinity. Its high content of brittle minerals is favorable for the fracturing of reservoirs in source rock formations in the Qingxi Sag. The Xiagou Formation contains a great number of fair to excellent source rocks, and their organic matter（OM） came chiefly from plankton/algae and high plants as well as possibly bacterial organisms. The Xiagou Formation source rocks mainly contain Type II OM and some Type III and Type I OM, with good oil-generating potential. The source rock maturity is mainly in the early-mature and mature stages, and its Rovalue corresponding to oil peak is about 0.8%, which is lower than classic oil peak Rovalue of 1.0%; therefore, a great deal of hydrocarbon was generated before the classic oil peak Ro= 1.0%. Mature source rock in the Xiagou Formation tends to be distributed in the older members and at a greater depth. There is a better exploration potential of tight oil in the deep Qingxi Sag.
基金jointly supported by a grant from the National Natural Science Foundation of China(No.41490634)the National Key Basic Research Special Foundation of China(No.2015FY210500)
文摘Spectra are sensitive in detecting main minerals on the lunar surface from visible light to infrared light. Since spectral characteristics of minerals are closely related to their compositions and the maturity level of soil on the Moon, studying the compositions and distribution of elements and minerals on the lunar surface can help to understand the evolution of the Moon through remote sensing technology. The correlation between the spectral characteristics of Chang＇e-1 interference imaging spectrometry（IIM） reflectance images and the mineral contents of LSCC（Lunar Soil Characterization Consortium） lunar surface mineral samples was discussed and the spatial distributions of Fe O and Al_2O_3 contained in both pyroxene and plagioclase on LQ-4 were studied using the improved angle parameter method, MNF, and band ratio statistics. A comparison of the mapping results of the optical models by Lucey, Shkuractov and other researchers on Clementine and the gamma ray spectrometry data shows that the content error is within 0.6% for lunar mare areas and close to 1% for the highland areas. The tectonic framework on the lunar surface was also investigated. And based on integrated analysis of previous findings on topography of the lunar surface, Chang＇e LAM, CCD and LOLA images and the gravity anomalies data（Clementine GLGM-2）, the tectonic unit subdivision was established for LQ-4, the idea of subdividing the lunar tectonic units was proposed, and this will provide a good foundation for studying the lunar tectonic evolution.
基金supported by the National Natural Science Foundation of China(No.42090023,42102323,51734009,42102322)the Scientific Research and Technology Development Project of China National Petroleum Corporation(2022DJ5503)the Joint Geological Funds of the National Natural Science Foundation of China(U2244223)。
文摘Shale oil is one of the most promising alternative unconventional energies in the world,and Lucaogou Formation shows significant exploration potential,becoming the primary target in northwestern China.This paper compared the mechanical properties of shale layered samples from oil layer and interlayer of Lucaogou Formation,using uniaxial compressive tests with real-time micro-CT scanning.After that,the mineral analysis was conducted on one cross-section of the fractured sample to analyze the influence of mineral composition and distribution on micro-crack propagation.Such research has rarely been reported before.The results showed the surface porosity and elastic modulus of oil-bearing samples is larger than that of the interlayer samples,while the uniaxial compressive strength is lower.Besides,when there is only one dominant mineral with a content greater than 60%,a main crack tends to form at this area;When there are 2~3 major minerals with a content of 10%-60%,a fractured zone with many fine micro-cracks is more likely to form here.Finally,the higher the Moh's hardness of the mineral,the more difficult it is for micro-cracks to develop through it.
基金supported by the National Natural Science Foundation of China (Grant No. 42072194, U1910205)the Fundamental Research Funds for the Central Universities (800015Z1190, 2021YJSDC02)。
文摘Mechanical properties of shales are key parameters influencing hydrocarbon production – impacting borehole stability, hydraulic fracture extension and microscale variations in in situ stress. We use Ordovician shale(Sichuan Basin, China) as a type-example to characterize variations in mineral particle properties at microscale including particle morphology, form of contact and spatial distribution via mineral liberation analysis(MLA) and scanning electron microscopy(SEM). Deformation-based constitutive models are then built using finite element methods to define the impact of various architectures of fracture and mineral distributions at nanometer scale on the deformation characteristics at macroscale.Relative compositions of siliceous, calcareous and clay mineral particles are shown to be the key factors influencing brittleness. Shales with similar mineral composition show a spectrum of equivalent medium mechanical properties due to differing particle morphology and mineral heterogeneity. The predominance of small particles and/or point-point contacts are conducive to brittle failure, in general, and especially so when quartz-rich. Fracture morphology, length and extent of filling all influence shale deformability. High aspect-ratio fractures concentrate stress at fracture tips and are conducive to extension, as when part-filled by carbonate minerals. As fracture spacing increases, stress transfer between adjacent fractures weakens, stress concentrations are amplified and fracture extension is favored. The higher the fractal dimension of the fracture and heterogeneity of the host the more pervasive the fractures. Moreover, when fractures extend, their potential for intersection and interconnection contributes to a reduction in strength and the promotion of brittle failure. Thus, these results provide important theoretical insights into the role of heterogeneity on the deformability and strength of shale reservoirs with practical implications for their stimulation and in the recovery of hydrocarbons from them.
基金Funded by the National Natural Science Foundation of China(50978093 and 51072050)the National Key Research Program(973 Project)(No.2009CB6231001)
文摘Based on the principle of ENV 196-4 ＂Methods of testing cement - Part 4 Quantitative determination of constituents or Chinese Standard GB/12960-2007 Quantitative measurement of mineral admixtures in cement, methods were developed for quantitative determination of fly ash, slag and limestone powder in fresh cement pastes, mortars and concretes. Limestone powder was determined using thermal analysis method. The residue content of fly ash on an 80um sieve, and silt contents of aggregate were also considered during the quantitative determination of mineral composition of quaternary cementitious system. With the developed methods, the deviations between the measured and the actual mineral contents of the constituent in the eemantitious material in fresh cement paste, mortar and concrete, were within 3%.
基金supported by Directorate General of Resources for Science,Technology and Higher Education,Ministry of Research,Technology and Higher Education of the Republic of Indonesia(grant No.653/PKS/ITS/2017)
文摘Objective: To investigate the proximate and mineral composition of the Piper retrofractum(P. retrofractum) vahl. Fruit and to evaluate its total alkaloids, phenol and flavonoid. Methods: The proximate composition of P. retrofractum fruit was ananlyzed using standard protocols according to Indonesian Standard and Association of Official Analytical Chemist. Meanwhile, mineral composition of the fruit was analyzed using inductively coupled plasma-mass spectrometry. Phytochemical screening and quantification were performed using standard protocols according to Harborn and spectrophotometric methods. Results: The results showed that P. retrofractum fruit contained carbohydrate(63.4%), crude protein(11.4%), total ash(4.29%), dietary fiber(28.8%) and total fat(2.97%). The fruit also contained calcium, copper, iron, magnesium, phosphor, potassium, sodium and zinc in different concentrations. Additionally, quinone, sterol, glycosides and alkaloid were detected in both n-hexane and ethyl acetate extracts. Moreover, tannin was presented also in ethylacetate and methanol extracts. Meanwhile, methanol extract contained sterol, glycosides, flavones, tannin and alkaloid. The results also revealed that methanol extract of the fruit contained highest phenol compared to other extract. Finally, small quantity of flavonoid(0.060 0%±0.000 2%) was observed. Conclusions: The overall results show that P. retrofractum contains potential nutritional and phytochemicals values, which support their function for pharmaceutical purposes.
基金sponsored by the Natural Science Youth Project of University Scientific Research Plan in Xinjiang(XJEDU2021Y053)the Talent introduction research project of China University of Petroleum-Beijing at Karamay(XQSQ20200056)the Strategic Cooperation Tech-nology Projects of CNPC and CUPB(Grant No.ZLZX2020-01).
文摘Natural fractures are widely distributed in shale reservoirs.During the hydraulic fracturing process,frictional slip occurring on natural fractures can increase the reservoir permeability and is of great significance to improve the efficiency of reservoir stimulation.Shale contains a large amount of clay and organic matter,and its frictional behavior is different from that of other previously studied lithologies.In this paper,the frictional behavior of shale is analyzed,and the results show that the frictional behavior is controlled by the content of clay and organic matter.As the content of clay and organic matter increases,the micro support type transforms from the particle support mode by hard quartz mineral to matrix support mode by plastic clay and organic matter.Accordingly,the shear strength and friction coefficient of shale both decrease,and the shear type transforms from brittle to plastic.When the content of clay and organic matter is low,the asperity of friction surfaces will break in a brittle manner and the wear degree of surfaces is low.Therefore,fractures are still featured by moderate apertures after friction.The lower the content of clay and organic matter is,the easier the asperity of crack surfaces supports themselves,and the higher the fracture residual permeability is.Thus,promoting shear slip is the main measure of reservoir stimulation.However,when the content of clay and organic matter is high,the remaining post-slip fracture aperture is small.It is difficult to increase reservoir permeability through the frictional slip of natural fractures,and in this situation,the proppant support efficiency needs to be improved.
文摘Spices which are widely used in Southwest Nigeria have aroma, enhance taste of food and possess medicinal values. Proximate, mineral composition and phytochemical screening of ten randomly selected spices were carried out. Recommended procedures were used for the analyses. Mineral composition was determined using flame photometer, colorimeter and （Atomic Absorption Spectrophotometer）. The proximate composition showed that protein was high at 12.04% in Zingiber officinale and low at 2.1% in Xylopia aethiopica. Ocimium gratissium contained high moisture content at 82.1%, while Tetrapleura tetraptera had the least value of 3.5%. High ash content was recorded in Ocimum gratissium at 13.68% and lowest 0.98% in Allium cepa. For carbohydrate, Allium cepa had the highest value of 78.36%, while Allium setiva had the least value of 19.48%. Mineral composition showed high value of calcium 712 mg/100g, magnesium 172.2 mg/100g, potassium 868.5 mg/100g, sodium 75.85 mg/100g, and manganese 95.38 mg/100g in Allium sativa, Xylopia aethiopica, Momodara myristica, Ocimum gratissimum, Tetrapleura tetraptera respectively. Aframomium meleghueta had high value of iron and zinc at 85 mg/100g and 97 mg/100g respectively and also high presence of alkaloids, glycosides, saponins and tarmis. High values of saponins and triterpenoids were observed in Zingiber officinale and Ocimum gratissimum respectively. This study showed that spices have greater use in medicine and as food supplement.
文摘The expansion of hydroponics in many countries of the world in the last few decades may be ascribed to the ability of soilless growing systems to avoid various problems arising from the use of the soil. Cucumber （Cucurnis sativus L.） and zucchini （Cucurbita pepo L.） plants were grown in closed-soilless culture under unheated-greenhouse conditions at the experimental farm of University of Tuscia, Central Italy to evaluate the effects of four substrates （rockwool, pumice, perlite, and cocofiber） on growth, yield and plant mineral composition. For both cultures, plants grown in cocofiber, perlite and pumice yielded more than those grown in rockwool. The better temperature regime in cocofiber, perlite and pumice was due to the greater thermal inertia compared to rockwool slabs. Thc concentration of N in zucchini and cucumber leaves was significantly higher in cocofiber, perlite and pumice in comparison to the rockwool treatment. The concentration of K was significantly affected by the substrate only for the zucchini squash with the highest value recorded on the organic substrate （cocofiber）, whereas the Ca concentration was significantly influenced by the growing media only for cucumber with the highest value observed on pumice. Finally, the lowest Mg concentration in leaf tissue was observed on plants grown with the rockwool substrate for both zucchini squash and cucumber. We can conclude that cocofiber, perlite and pumice are suitable for zucchini and cucumber production in closed soilless system, whereas the use of rockwool is more suitable for crops grown under heated greenhouse conditions.
文摘Ferrimagnetic materials such as natural magnetite are used for practical applications because of their electronic, magnetic and catalytic properties in the degradation of organic compounds. In order to determine its physicochemical properties in relation to its catalytic activity, the natural magnetite of Ofoud Mount (Niger) is characterized by X-ray florescence (XRF), X-ray diffraction (DRX), specific surface area (BET) and Fourier transformed infrared (FTIR). The result shows an iron content of 97.09% and a specific surface area of 69.742 m<sup>2</sup>/g. The crystal structure of magnetite is cubic with lattice parameters <i>α</i> = <i>β</i> = <i>γ</i> = 90°, a (Å) = b (Å) = c (Å) = 8.3740. The results of this study suggest that the natural magnetite of Ofoud Mount can be used as iron source in various fields of science despite the presence of a few impurities that can improve its catalytic activity.
