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Physicochemical properties and biological activities of polysaccharides from the peel of Dioscorea opposita Thunb.extracted by four different methods 被引量:4
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作者 Zuowei Zhao Li Wang +4 位作者 Yuan Ruan Chunnan Wen Menghuan Ge Yanyan Qian Bingji Ma 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期130-139,共10页
Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-com... Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-compressed water extraction(HCW)and enzyme-assisted extraction(EAE),on the yields,physicochemical properties,hypoglycemic and antioxidant activities of polysaccharides from DTTP were studied and compared.Among these DTTP polysaccharides,DTTP-HA was outstanding in several respects.DTTP-HA was the most water soluble;it had the highest total carbohydrate content(85.08%),the highest uronic acid(13.20%)and the highest thermal stability.DTTP-HA and DTTP-W possessed a triple-helix structure.These 4 kinds of polysaccharides have the same types of monosaccharides,but in different molar percentages.Extraction method had a significant impact on the microstructures of the extracted polysaccharides.DTT-HA exhibited irregular structure with many holes.Among the 4 extracted methods,the DTTP-HA and DTTP-W initially exhibited higher hypoglycemic and antioxidant activities.The better bioactivities of DTTP-HA may be related to the above factors.The findings indicated that acid extraction is an effective method to extract polysaccharides with high biological activities from DTTP. 展开更多
关键词 Dioscorea opposita Thunb peel POLYSACCHARIDES Different extraction methods physicochemical characteristics biological activities
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Improvements of marine clay slurries using chemicale-physical combined method(CPCM) 被引量:1
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作者 Dongqing Wu Wenyu Xu Romy Tjuar 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第2期220-225,共6页
In this paper, the effectiveness, applicability and validity of chemicalephysical combined methods(CPCMs) for treatment of marine clay (MC) slurries were evaluated. The method CPCM1 combineschemical stabilization ... In this paper, the effectiveness, applicability and validity of chemicalephysical combined methods(CPCMs) for treatment of marine clay (MC) slurries were evaluated. The method CPCM1 combineschemical stabilization and vacuum preloading (VP), while CPCM2 is similar to CPCM1 but includes boththe application of surcharge and use of geo-bags to provide confinement during surcharge preloading.The key advantage of CPCM2 using geo-bags is that the surcharge can be immediately applied on thechemically stabilized slurries. Two types of geo-bags were investigated under simulated land filling anddyke conditions, respectively. The test results show that the shear strength (cu) of treated slurry byCPCM2 is generally much higher than that by CPCM1. Besides, the use of CPCM2 can significantly reducethe treatment time due to the short drainage paths created by geo-bags. Overall, CPCM2 allows fasterconsolidation and higher preloading that help to achieve higher mechanical properties of the stabilizedslurry. There are consistent relationships between cU and water content of slurries treated by CPCM2.Several important observations were also made based on comparisons of experimental data. 2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved. 展开更多
关键词 chemical e physical combined method(CPCM) Soil improvement Marine clay(MC) slurry Land reclamation chemical stabilization Vacuum preloading(VP) Geo-bags SURCHARGE
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Effects of Varieties and Cooking Methods on Physical and Chemical Characteristics of Cooked Rice 被引量:1
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作者 Merynda Indriyani SYAFUTRI Filli PRATAMA +1 位作者 Friska SYAIFUL Achmad FAIZAL 《Rice science》 SCIE CSCD 2016年第5期282-286,共5页
To analyze the effect of different lowland rice varieties and different cooking methods on physical and chemical characteristics of cooked rice. A factorial randomized block design with two factors was used and each c... To analyze the effect of different lowland rice varieties and different cooking methods on physical and chemical characteristics of cooked rice. A factorial randomized block design with two factors was used and each combination of the factors was repeated three times. The first factor was rice variety(Ciherang and Ciliwung) and the second factor was the cooking method(stovetop, boiling and steaming, and rice cooker). Results showed that Ciherang and Ciliwung varieties were classified into slender grain rice type with yellowred color. The amylose content of Ciherang was classified as moderate, while the amylose content of Ciliwung classified as low. The most abundant amino acid contained in Ciherang and Ciliwung varieties was glutamic acid. Statistical analysis showed that cooking method had significant effects on texture, lightness, chroma, hue and moisture content of cooked rice. Rice cooked with liwet method had the lowest texture value, lowest lightness value, highest chroma value, and highest moisture content. 展开更多
关键词 physical and chemical characteristic cooking method rice variety amino acid
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Bound-Preserving Discontinuous Galerkin Methods with Modified Patankar Time Integrations for Chemical Reacting Flows
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作者 Fangyao Zhu Juntao Huang Yang Yang 《Communications on Applied Mathematics and Computation》 EI 2024年第1期190-217,共28页
In this paper,we develop bound-preserving discontinuous Galerkin(DG)methods for chemical reactive flows.There are several difficulties in constructing suitable numerical schemes.First of all,the density and internal e... In this paper,we develop bound-preserving discontinuous Galerkin(DG)methods for chemical reactive flows.There are several difficulties in constructing suitable numerical schemes.First of all,the density and internal energy are positive,and the mass fraction of each species is between 0 and 1.Second,due to the rapid reaction rate,the system may contain stiff sources,and the strong-stability-preserving explicit Runge-Kutta method may result in limited time-step sizes.To obtain physically relevant numerical approximations,we apply the bound-preserving technique to the DG methods.Though traditional positivity-preserving techniques can successfully yield positive density,internal energy,and mass fractions,they may not enforce the upper bound 1 of the mass fractions.To solve this problem,we need to(i)make sure the numerical fluxes in the equations of the mass fractions are consistent with that in the equation of the density;(ii)choose conservative time integrations,such that the summation of the mass fractions is preserved.With the above two conditions,the positive mass fractions have summation 1,and then,they are all between 0 and 1.For time discretization,we apply the modified Runge-Kutta/multi-step Patankar methods,which are explicit for the flux while implicit for the source.Such methods can handle stiff sources with relatively large time steps,preserve the positivity of the target variables,and keep the summation of the mass fractions to be 1.Finally,it is not straightforward to combine the bound-preserving DG methods and the Patankar time integrations.The positivity-preserving technique for DG methods requires positive numerical approximations at the cell interfaces,while Patankar methods can keep the positivity of the pre-selected point values of the target variables.To match the degree of freedom,we use polynomials on rectangular meshes for problems in two space dimensions.To evolve in time,we first read the polynomials at the Gaussian points.Then,suitable slope limiters can be applied to enforce the positivity of the solutions at those points,which can be preserved by the Patankar methods,leading to positive updated numerical cell averages.In addition,we use another slope limiter to get positive solutions used for the bound-preserving technique for the flux.Numerical examples are given to demonstrate the good performance of the proposed schemes. 展开更多
关键词 Compressible Euler equations chemical reacting flows Bound-preserving Discontinuous Galerkin(DG)method Modified Patankar method
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Analysis of the Cicatricial Acceleration Method (MAC®) in Skin Repair in Wistar Rattus norvegicus with Induced Chemical Burns
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作者 Marcus Vinicius de Mello Pinto Sandroval Francisco Torres +9 位作者 Aline Ronis Sampaio Karin Yuri Fernandez Iturra Miriam Viviane Baron Patricia Froes Carlos Ruiz da Silva Daiane Paza Maria Elena Silva Alvarez Josefa Jeanette Ugalde Juliano Tibola Esteban Fortuny 《Journal of Biosciences and Medicines》 2024年第9期204-214,共11页
Introduction: The cicatricial acceleration method (MAC®) promotes photobiological effects of an anti-inflammatory and healing nature. Its therapeutic radiation is emitted, producing photobiostimulant effects that... Introduction: The cicatricial acceleration method (MAC®) promotes photobiological effects of an anti-inflammatory and healing nature. Its therapeutic radiation is emitted, producing photobiostimulant effects that result in rapid tissue repair and better tissue quality. The treatment of burns has always been a challenge, which involves both performing surgery and controlling and guiding scar regeneration, avoiding possible morbidities. Objective: To evaluate the effects of applying the MAC methodology with an AlGa (aluminum, gallium arsenide) laser on the time and quality of tissue repair in the skin of rats after induced chemical burns. Method: 22 adult male rats were subjected to a second-degree chemical burn on the back using 50% trichloroacetic acid. After the burns, the animals were randomly separated into 2 groups: control and experimental. The control group (G1) received placebo laser therapy and the laser group (G2) underwent laser irradiation with an energy density of 100 J/cm2. Histological analysis and macroscopic evaluation were carried out by means of the paper template method. Results: Group G1 showed (53%) of the necrosis area and group G2 showed (11%) necrosis area. Conclusion: The cicatricial acceleration method (MAC®) favored the repair of wounds caused by a 2nd-degree chemical burn, optimizing time and improving quality. 展开更多
关键词 chemical Burn HEALING SCARRING Cicatricial Acceleration method (MAC®) Tissue Repair
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Effects of Different Farming Methods and Their Effects on Soil Physicochemical Properties of Guilin Maojian Tea Gardens
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作者 Lingyun ZHANG Shuyi LI +5 位作者 Sisi Qin Changjian JIANG Qifa LONG Min SU Chusheng LIU Qianhua WU 《Agricultural Biotechnology》 CAS 2018年第5期186-190,共5页
In order to further optimize the cultivation and agronomic technology of Guilin Maojian tea gardens, the effects, efficiencies and costs of different farming methods and their effects on the physiochemical properties ... In order to further optimize the cultivation and agronomic technology of Guilin Maojian tea gardens, the effects, efficiencies and costs of different farming methods and their effects on the physiochemical properties of tea garden soil were studied through the modification of the test sites with the non-farming land as the control. The results showed that human farming, mini-tiller farming and crawler tractor farming could improve the physical and chemical properties of soil. After farming, the soil had good water retention but low moisture content compared to the control group, while the soil bulk density and hardness value were significantly lower than those of the control, and the porosity of soil was significantly higher than that of contrast. With the passage of time, soil bulk density and hardness value gradually increased after farming, while the porosity of soil decreased gradually. There were great differences in the effects, efficiencies and costs of different farming methods. Crawler tractor had the best and most stable farming effect, and the operation efficiency was 10 times that of human farming while the cost was only 0.39 times of human farming. Therefore, it was feasible to adopt mini-tiller or crawler tractor to carry out mechanical farming of Guilin Maojian tea garden, which provided theoretical references for the soil property improvement using mechanical farming and was favorable for promoting the popularization of farming machines and the acceleration of mechanization of tea gardens. But for tea plantations that are intended to be mechanized, apart from the mechanical and technical personnel to be configured in place, the site conditions, planting modes and mechanical way reservation of tea garden should be planned accordingly. It is recommended to select flat or gentle slope for reclamation, and preference is given to non-sexual tea tree varieties with big line spacing over 180 cm long. Moreover, the main road construction should be more than 3.0 m, and trunk road 2.0 m or above. And isolation ditch and drain should be set between the tea garden and the surrounding mountain forests and farmland. 展开更多
关键词 Guilin Maojian tea Tea garden Farming methods SOIL physical and chemical properties
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Emergency control of Spartina alterniflora re-invasion with a chemical method in Chongming Dongtan,China 被引量:11
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作者 Zhi-yuan Zhao Yuan Xu +3 位作者 Lin Yuan Wei Li Xiao-jing Zhu Li-quan Zhang 《Water Science and Engineering》 EI CAS CSCD 2020年第1期24-33,共10页
The exotic species Spartina alterniflora(S.alterniflora)seriously threatens the stability and functioning of saltmarsh ecosystems in the Yangtze Estuary.Ambitious efforts have been undertaken to control this species,b... The exotic species Spartina alterniflora(S.alterniflora)seriously threatens the stability and functioning of saltmarsh ecosystems in the Yangtze Estuary.Ambitious efforts have been undertaken to control this species,but subsequent re-invasion is frequent,presenting a significant barrier to restoration.The complexity and high cost of integrated physical control programs has necessitated a shift in focus,leading to considerable attention being paid to the potential of herbicides to control S.alterniflora.To find a strategy for emergency control of small and scattered patches of re-invading S.alterniflora,an in situ field experiment using Gallant(Haloxyfop-R-methyl)herbicide was conducted.The growth parameters of plant density and height were used to evaluate the control efficiency of different treatment dosages and times and sediment samples were taken for environmental toxicity analysis.The results show the following:(1)the control efficacy of the maximum proposed application dose(2.70 g/m2)was 92%for continuous swards and 100%for small patches,while those of other dosages(0.45 g/m2,0.90 g/m2,and 1.35 g/m2)were lower than 40%;(2)the appropriate implementation time was July to August with 100%mortality resulting from a single application,while S.alterniflora was shown to be capable of recovering rapidly after treatment in May;and(3)there were no significant differences in the community structure of meiofauna among the herbicide treatments and the control,and no herbicide residues were detected in sediment samples collected from treatment areas.This chemical control method was implemented in the Shanghai Chongming Dongtan National Bird Nature Reserve(CDNR).The results of this study indicate that Gallant is an environmentally friendly herbicide with high efficiency,which can be adopted for emergency control of re-invading S.alterniflora. 展开更多
关键词 SPARTINA alterniflora Re-invasion chemical control method Gallant YANGTZE ESTUARY
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Synthesis and Characterization of Y-Doped Mesoporous CeO_2 Using A Chemical Precipitation Method 被引量:5
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作者 宋晓岚 江楠 +2 位作者 李宇焜 徐大余 邱冠周 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第4期428-433,共6页
Using cetyltrimethylammonium bromide (CTAB) as the template agent, cerium nitrate as the cerium resource, yttrium nitrate as the yttrium resource, and ammonium carbonate as the precipitating agent, mesoporous CeO2 p... Using cetyltrimethylammonium bromide (CTAB) as the template agent, cerium nitrate as the cerium resource, yttrium nitrate as the yttrium resource, and ammonium carbonate as the precipitating agent, mesoporous CeO2 powders doped with different yttrium contents were successfully synthesized using a chemical precipitation method, under an alkalescent condition. Properties of the obtained samples were characterized and analyzed with X-ray diffraction (XRD), energy dispersive analysis of X-rays (EDAX), transmission electron microscopy (TEM), infrared (IR) absorbance, and the BET method. For the prepared samples with 20% (molar ratio) Y-doped content, a BET specific surface area of 106. 6 m^2 · g^- 1, with an average pore size of3~27 nm were obtained. XRD patterns showed that the doped samples were with a cubic fluorite structure. TEM micrographs revealed that the doped samples showed a spherical morphology with a diameter ranging from 20 to 30 nm and a round pore shape. IR results indicated that the Ce-O-Ce vibration intensity decreased as the Y-doped content increased. N2 adsorption-desorption isotherms showed that the samples possessed typical mesopore characteristics. The average pore size of the samples decreased alter mesoporous CeO2 was doped with yttrium, and the average pore size decreased largely as the Y-doped content increased. 展开更多
关键词 mesoporous ceria Y-doped chemical precipitation method SYNTHESIS characterization rare earths
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Modified Augmented Lagrange Multiplier Methods for Large-Scale Chemical Process Optimization 被引量:6
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作者 梁昔明 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第2期167-172,共6页
Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studi... Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studied in this paper. The Lagrange function contains the penalty terms on equality and inequality constraints and the methods can be applied to solve a series of bound constrained sub-problems instead of a series of unconstrained sub-problems. The steps of the methods are examined in full detail. Numerical experiments are made for a variety of problems, from small to very large-scale, which show the stability and effectiveness of the methods in large-scale problems. 展开更多
关键词 modified augmented Lagrange multiplier methods chemical engineering optimization large-scale non- linear constrained minimization numerical experiment
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Fischer–Tropsch synthesis using Co and Co-Ru bifunctional nanocatalyst supported on carbon nanotube prepared via chemical reduction method 被引量:2
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作者 Jafar Shariati Ali Haghtalab Amir Mosayebi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第1期9-22,共14页
We used a chemical reduction method to synthesize the catalysts of cobalt(Co) and cobalt-ruthenium(Co-Ru) bifunctional supported on carbon nanotubes(CNTs) for Fischer–Tropsch synthesis(FTS) in a fixedbed reactor. The... We used a chemical reduction method to synthesize the catalysts of cobalt(Co) and cobalt-ruthenium(Co-Ru) bifunctional supported on carbon nanotubes(CNTs) for Fischer–Tropsch synthesis(FTS) in a fixedbed reactor. These Co-Ru/CNTs catalysts were synthesized with various weight proportions of Ru/Co(0.1 to 0.4 wt%) with keeping a fixed amount of cobalt(10 wt%). Moreover, for comparison purpose, CNTs supported Co-and Co(Ru)-based catalysts at same loading as the above catalysts were prepared through impregnation method. We characterize the present catalysts through the various techniques such as Energy–dispersive X-ray(EDX), Transmission Electron Microscopy(TEM), Brunauer–Emmett–Teller(BET),Hydrogen-Temperature-Programmed Reduction(H_2-TPR), Hydrogen-Temperature-Programmed Desorption(H_2-TPD) and O_2 titration. Thus using the chemical reduction method, a narrow particle size distribution was obtained so that the small cobalt particles were confined inside the CNTs. The Co-based catalyst prepared by impregnation was compared with the Co-Ru catalysts at the same loading. The results demonstrated that the use of chemical reduction method led to decrease the average Co oxide cluster size to8.7 nm so that the reduction enhanced about 24% and stabilized an earlier time at the stream. Among the prepared catalysts, the results indicated that the Co-Ru/CNTs catalysts demonstrated high catalytic activity with the highest long-chain hydrocarbons(C_(5+)), selectivity up to 74.76%, which was higher than those we obtained by the Co-Ru/γ-Al_2O_3(61._20%), Co/CNTs(43.68%) and Co/γ-Al_2O_3(37.69%). At the same time, comparing with those catalyst synthesized by impregnation, the use of chemical reduction led to enhancement of the C_(5+) selectivity from 59.30% to 68.83% and increment in FTS rate about 11% for the Co-Ru/CNTs catalyst. 展开更多
关键词 Cobalt-ruthenium Carbon nanotubes FISCHER-TROPSCH SYNTHESIS Catalyst nanoparticles chemical reduction method
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Effects of Different Application Methods and Application Rates of Biological Nano-Selenium on the Quality of Passion Fruit 被引量:5
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作者 Wei HUANG Minying SHEN +2 位作者 Zhaoliang LIU Yu ZHANG Daobo WANG 《Medicinal Plant》 CAS 2020年第3期68-69,92,共3页
[Objectives]To study the effects of different application methods and application rates of biological nano-selenium on the quality of passion fruit.[Methods]In this experiment,passion fruit Tainong 1 was sprayed with ... [Objectives]To study the effects of different application methods and application rates of biological nano-selenium on the quality of passion fruit.[Methods]In this experiment,passion fruit Tainong 1 was sprayed with biological nano-selenium.The concentration of spraying refers to the recommended application rate of biological nano-selenium manufacturers.Three treatments with different concentrations were carried out:3,4.5 and 6 L/ha biological nano-selenium was sprayed on 100%root,(50%root+50%leaf surface)and 100%leaf surface of passion fruit,respectively.[Results]From the aspects of economic cost and rational utilization of resources,spraying 3 L/ha selenium fertilizer on the leaves of passion fruit played the best role in improving the quality of passion fruit.[Conclusions]To study the selenium-rich production technology of agricultural products and improve the quality of agricultural products is of great significance for improving human health and producing high-quality agricultural products. 展开更多
关键词 biological nano-selenium Fertilization method Passion fruit QUALITY
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Analytical methods for determination of terbinafine hydrochloride in pharmaceuticals and biological materials 被引量:2
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作者 Basavaiah Kanakapura Vamsi Krishna Penmatsa 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第3期137-149,共13页
Terbinafine is a new powerful antifungal agent indicated for both oral and topical treatment of myco- sessince. It is highly effective in the treatment of determatomycoses. The chemical and pharmaceutical analysis of ... Terbinafine is a new powerful antifungal agent indicated for both oral and topical treatment of myco- sessince. It is highly effective in the treatment of determatomycoses. The chemical and pharmaceutical analysis of the drug requires effective analytical methods for quality control and pharmacodynamic and pharmacokinetic studies. Ever since it was introduced as an effective antifungal agent, many methods have been developed and validated for its assay in pharmaceuticals and biological materials. This article reviews the various methods reported during the last 25 years. 展开更多
关键词 Terbinafine hydrochloride Analytical methods Pharmaceuticals biological materials
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Numerical simulation of non-Archie electrophysical property of saturated rock with lattice Boltzmann method 被引量:2
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作者 Yue Wenzheng Tao Guo +1 位作者 Liu Dongming Yang Wendu 《Petroleum Science》 SCIE CAS CSCD 2009年第1期24-28,共5页
The electrophysical property of saturated rocks is very important for reservoir identification and evaluation. In this paper, the lattice Boltzmann method (LBM) was used to study the electrophysical property of rock... The electrophysical property of saturated rocks is very important for reservoir identification and evaluation. In this paper, the lattice Boltzmann method (LBM) was used to study the electrophysical property of rock saturated with fluid because of its advantages over conventional numerical approaches in handling complex pore geometry and boundary conditions. The digital core model was constructed through the accumulation of matrix grains based on their radius distribution obtained by the measurements of core samples. The flow of electrical current through the core model saturated with oil and water was simulated on the mesoscopic scale to reveal the non-Archie relationship between resistivity index and water saturation (I-Sw). The results from LBM simulation and laboratory measurements demonstrated that the I-Sw relation in the range of low water saturation was generally not a straight line in the log-log coordinates as described by the Archie equation. We thus developed a new equation based on numerical simulation and physical experiments. This new equation was used to fit the data from laboratory core measurements and previously published data. Determination of fluid saturation and reservoir evaluation could be significantly improved by using the new equation. 展开更多
关键词 Non-Archie relation digital core model lattice Boltzmann method numerical simulation rock physical experiment
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Preparation of calcium stannate by modified wet chemical method 被引量:3
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作者 何则强 李新海 +3 位作者 刘恩辉 侯朝辉 邓凌峰 胡传跃 《Journal of Central South University of Technology》 2003年第3期195-197,共3页
A modified wet chemical route for low-temperature synthesis of the calcium stannate CaSnO3, a potentialmaterial for dielectric applications is reported. Firstly, a precursor CaSn(OH)6 was prepared using tin tetrachlor... A modified wet chemical route for low-temperature synthesis of the calcium stannate CaSnO3, a potentialmaterial for dielectric applications is reported. Firstly, a precursor CaSn(OH)6 was prepared using tin tetrachloride,calcium chloride and sodium hydroxide at room temperature. Then the precursor was annealed at relatively low tem-perature of 600 ℃ to obtain CaSnO3. The phase identification, thermal behavior and surface morphology of the sam-ples were characterized by element analysis, X-ray diffraction (XRD), thermo-gravimetric (TG) analysis and deriva-tive thermo-gravimetric (DTG) analysis, Fourier transform infrared spectroscopy (FTIR) and scanning electron mi-croscopy (SEM) in detail. The results show that CaSnO3 obtained by this method possesses a cubic perovskitestructure with average grain size of 5 μm. 展开更多
关键词 CaSnO3 WET chemical method PREPARATION characterization
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A simple physical mixing method for MnO2/MnO nanocomposites with superior Zn^2+storage performance 被引量:3
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作者 Xiao-bei ZANG Ling-tong LI +5 位作者 Zhi-xin SUN Rabah BOUKHERROUB Jia-xin MENG Kun-peng CAI Qing-guo SHAO Ning CAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第12期3347-3355,共9页
MnO2/MnO cathode material with superior Zn^2+storage performance is prepared through a simple physical mixing method.The MnO2/MnO nanocomposite with a mixed mass ratio of 12:1 exhibits the highest specific capacity(36... MnO2/MnO cathode material with superior Zn^2+storage performance is prepared through a simple physical mixing method.The MnO2/MnO nanocomposite with a mixed mass ratio of 12:1 exhibits the highest specific capacity(364.2 mA·h/g at 0.2C),good cycle performance(170.4 mA·h/g after 100 cycles)and excellent rate performance(205.7 mA·h/g at 2C).Analysis of cyclic voltammetry(CV)data at various scan rates shows that both diffusioncontrolled insertion behavior and surface capacitive behavior contribute to the Zn2+storage performance of MnO2/MnO cathodes.And the capacitive behavior contributes more at high discharge rates,due to the short paths of ion diffusion and the rapid transfer of electrons. 展开更多
关键词 zinc-ion battery MnO2/MnO cathode material physical mixing method reaction kinetics
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Homotopy Analysis Method for Solving Biological Population Model 被引量:2
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作者 A.A.M.Arafa S.Z.Rida H.Mohamed 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第11期797-800,共4页
In this paper,the homotopy analysis method (HAM) is applied to solve generalized biological populationmodels.The fractional derivatives are described by Caputo's sense.The method introduces a significant improveme... In this paper,the homotopy analysis method (HAM) is applied to solve generalized biological populationmodels.The fractional derivatives are described by Caputo's sense.The method introduces a significant improvementin this field over existing techniques.Results obtained using the scheme presented here agree well with the analyticalsolutions and the numerical results presented in Ref.[6].However,the fundamental solutions of these equations stillexhibit useful scaling properties that make them attractive for applications. 展开更多
关键词 biological populations model fractional calculus homotopy analysis method Mittag-Leffier function
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Preparation methods,biological activities,and potential applications of marine algae oligosaccharides:a review 被引量:2
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作者 Lixin Zheng Yang Liu +2 位作者 Shijie Tang Wancong Zhang Kit-Leong Cheong 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期359-370,共12页
Marine algae are valuable sources of health-promoting molecules that have been consumed by Asians for decades.Among aquatic flora,marine algae stand out in terms of high content of marine algae polysaccharides(MAP)suc... Marine algae are valuable sources of health-promoting molecules that have been consumed by Asians for decades.Among aquatic flora,marine algae stand out in terms of high content of marine algae polysaccharides(MAP)such as carrageenan,alginate,fucoidan,laminaran,agarose,rhamnan,and ulvan.When hydrolyzed,MAP generate marine algae oligosaccharides(MAO),which have attracted interest in recent years due to their superior solubility compared with MAP.Besides,MAO have been demonstrated numerous biological activities including antioxidant,antidiabetic,anti-inflammatory,antimicrobial,and prebiotic activities.Thus,this review summarizes the main chemical classes of MAO,their sources,and the main processes used for their production(i.e.,physical,chemical,and biological methods),coupled with a discussion of the advantages and disadvantages of these methods.Highlights of the biological activities of MAO and their potential applications in food,nutraceutical,and pharmaceuticals would also be discussed and summarized. 展开更多
关键词 Marine algae MAO Preparation methods biological activities Potential applications
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A Physical Method of Analyzing theMechanism of Continental StrongShocks from Crustal Movement 被引量:4
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作者 Shen Chongyang,Wu Yun,and Gan Jiasi Institute of Seismology. CSB, Wuhan 430071,China 《Earthquake Research in China》 2001年第3期282-297,共16页
In order to analyze the mechanism of continental strong shocks from the angle of crustal movement using the data of repeated geodetic survey, this paper has proposed a physical method; it analyzes the mechanism of den... In order to analyze the mechanism of continental strong shocks from the angle of crustal movement using the data of repeated geodetic survey, this paper has proposed a physical method; it analyzes the mechanism of density change due to the occurrence of strong shocks by use of the physical quantity that reflects the time change of crustal density. (1) The general theory of the time change of density in the earth’ s interior and the theory of the time change of single layer density have been introduced, and an algorithm of stepwise iteration has been proposed; (2) The effect of the change of single layer density caused by fault dislocation has been analyzed in brief; (3) The characteristics of the time change of crustal density in the south of the seismogenic region before the 1996 Lijiang earthquake with M_L =7.0 have been studied; (4) The precursor model or causal mechanism of strong shocks possibly existing in the time change of crustal density has been investigated preliminarily. 展开更多
关键词 CRUSTAL MOVEMENT Mechanism of STRONG SHOCKS Density change physical method
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Physical Parameter Identification Method Based on Modal Analysis for Two-axis On-road Vehicles:Theory and Simulation 被引量:3
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作者 ZHENG Minyi ZHANG Bangji +1 位作者 ZHANG Jie ZHANG Nong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第4期756-764,共9页
Physical parameters are very important for vehicle dynamic modeling and analysis.However,most of physical parameter identification methods are assuming some physical parameters of vehicle are known,and the other unkno... Physical parameters are very important for vehicle dynamic modeling and analysis.However,most of physical parameter identification methods are assuming some physical parameters of vehicle are known,and the other unknown parameters can be identified.In order to identify physical parameters of vehicle in the case that all physical parameters are unknown,a methodology based on the State Variable Method(SVM) for physical parameter identification of two-axis on-road vehicle is presented.The modal parameters of the vehicle are identified by the SVM,furthermore,the physical parameters of the vehicle are estimated by least squares method.In numerical simulations,physical parameters of Ford Granada are chosen as parameters of vehicle model,and half-sine bump function is chosen to simulate tire stimulated by impulse excitation.The first numerical simulation shows that the present method can identify all of the physical parameters and the largest absolute value of percentage error of the identified physical parameter is 0.205%;and the effect of the errors of additional mass,structural parameter and measurement noise are discussed in the following simulations,the results shows that when signal contains 30 d B noise,the largest absolute value of percentage error of the identification is 3.78%.These simulations verify that the presented method is effective and accurate for physical parameter identification of two-axis on-road vehicles.The proposed methodology can identify all physical parameters of 7-DOF vehicle model by using free-decay responses of vehicle without need to assume some physical parameters are known. 展开更多
关键词 Parameter identification free-decay response state variable method modal parameter physical parameter
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Source Apportionment of Ambient PM_(10) in the Urban Area of Longyan City,China:a Comparative Study Based on Chemical Mass Balance Model and Factor Analysis Method 被引量:1
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作者 QIU Li-min LIU Miao +2 位作者 WANG Ju ZHANG Sheng-nan FANG Chun-sheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第2期204-208,共5页
In order to identify the day and night pollution sources of PM10 in ambient air in Longyan City,the authors analyzed the elemental composition of respirable particulate matters in the day and night ambient air samples... In order to identify the day and night pollution sources of PM10 in ambient air in Longyan City,the authors analyzed the elemental composition of respirable particulate matters in the day and night ambient air samples and various pollution sources which were collected in January 2010 in Longyan with inductivity coupled plasma-mass spectrometry(ICP-MS).Then chemical mass balance(CMB) model and factor analysis(FA) method were applied to comparatively study the inorganic components in the sources and receptor samples.The results of factor analysis show that the major sources were road dust,waste incineration and mixed sources which contained automobile exhaust,soil dust/secondary dust and coal dust during the daytime in Longyan City,China.There are two major sources of pollution which are soil dust and mixture sources of automobile exhaust and secondary dust during the night in Longyan.The results of CMB show that the major sources are secondary dust,automobile exhaust and road dust during the daytime in Longyan.The major sources are secondary dust,soil dust and automobile exhaust during the night in Longyan.The results of the two methods are similar to each other and the results will guide us to plan to control the PM10 pollution sources in Longyan. 展开更多
关键词 Factor analysis(FA) method chemical mass balance(CMB) model Source apportionment Atmospheric particle PM10
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