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Correlations between mineral composition and mechanical properties of granite using digital image processing and discrete element method 被引量:3
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作者 Changdi He Brijes Mishra +3 位作者 Qingwen Shi Yun Zhao Dajun Lin Xiao Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第8期949-962,共14页
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
关键词 GRANITE Digital image processing Discrete element method Mineral composition Mechanical properties
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Effects of different processing methods on the lipid composition of hazelnut oil:a lipidomics analysis 被引量:3
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作者 Jiayang Sun Xiaonuo Feng +2 位作者 Chunmao Lyu Shuang Zhou Zixuan Liu 《Food Science and Human Wellness》 SCIE 2022年第2期427-435,共9页
Although hazelnut oil is rich in nutrients,its quality is greatly affected by how it is processed.However,no studies to date have comprehensively analyzed the lipid composition of hazelnut oil using different processi... Although hazelnut oil is rich in nutrients,its quality is greatly affected by how it is processed.However,no studies to date have comprehensively analyzed the lipid composition of hazelnut oil using different processing methods.Here,we conducted a lipidomics analysis using UPLC-QTOF-MS to characterize the lipid composition of cold-pressed hazelnut oil(CPO),ultrasonic-assisted hexane hazelnut oil(UHO)and enzyme-assisted aqueous hazelnut oil(EAO).A total of 10 subclasses of 98 lipids were identified,including35 glycerolipids(GLs),56 glycerophospholipids(GPs)and 7 sphingolipids(SPs).The total lipid and GL content were the highest in CPO,GP content was the highest in UHO and the ceramide content in SPs was most abundant in EAO.Multivariate statistical analysis showed that the lipid profiles of hazelnut oil prepared with different processing methods varied.Twelve significantly different lipids(TAG 54:3,TAG 52:2,TAG54:4,TAG 54:2,TAG 52:3,TAG 54:5,DAG 36:2,DAG 36:4,DAG 36:3,PC 36:2,PA 36:2 and PE 36:3)were identified,and these lipids could potentially be used as biomarkers to distinguish between hazelnut oil subjected to different processing methods.Our results provide useful information for hazelnut oil applications and new insight into the effects of edible oil processing. 展开更多
关键词 LIPIDOMICS Hazelnut oil processing method Lipid composition
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Impact of three different processing methods on the digestibility and allergenicity of Chinese mitten crab(Eriocheir sinensis)tropomyosin 被引量:1
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作者 Yufeng Lu Huafeng Cheng +2 位作者 Shaotong Jiang Lin Lin Jianfeng Lu 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期903-911,共9页
The tropomyosin(TM)fractions of crab protems may cause allergic reactions in mdividuals susceptible to allergies;however,efficient and safe methods by which to reduce such allergenicity are not currently available.The... The tropomyosin(TM)fractions of crab protems may cause allergic reactions in mdividuals susceptible to allergies;however,efficient and safe methods by which to reduce such allergenicity are not currently available.Therefore,in this study,the effects of three different processing methods,i.e.,microwave,ultrasound,and high temperature-pressure(HTP)treatments,on the digestion stability of TM from Chinese mitten crab muscle and the allergenicity of TM digestion products were explored.sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that microwaving had little effect on the digestion stability of TM.In contrast,ultrasound and HTP treatments facilitated the degradation of TM.Similarly,Western blotting and inhibition ELISA indicated that the IgE-binding activity of TM was significantly reduced after treatment with ultrasound or HTP.Among the three different proces sing methods,HTP was the most effective method for improving digestibility of TM and reducing immunoreactivity.This finding provides new insights into treatments for crab allergies. 展开更多
关键词 Chinese mitten crab TROPOMYOSIN processing methods IMMUNOREACTIVITY
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Alunite processing method selection using the AHP and TOPSIS approaches under fuzzy environment 被引量:3
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作者 Alizadeh Shahab Salari Rad Mohammad Mehdi Bazzazi Abbas Aghajani 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期1017-1023,共7页
Alunite is the most important non bauxite resource for alumina. Various methods have been proposed and patented for processing alunite, but none has been performed at industrial scale and no technical,operational and ... Alunite is the most important non bauxite resource for alumina. Various methods have been proposed and patented for processing alunite, but none has been performed at industrial scale and no technical,operational and economic data is available to evaluate methods. In addition, selecting the right approach for alunite beneficiation, requires introducing a wide range of criteria and careful analysis of alternatives.In this research, after studying the existing processes, 13 methods were considered and evaluated by 14 technical, economic and environmental analyzing criteria. Due to multiplicity of processing methods and attributes, in this paper, Multi Attribute Decision Making methods were employed to examine the appropriateness of choices. The Delphi Analytical Hierarchy Process(DAHP) was used for weighting selection criteria and Fuzzy TOPSIS approach was used to determine the most profitable candidates. Among 13 studied methods, Spanish, Svoronos and Hazan methods were respectively recognized to be the best choices. 展开更多
关键词 Alunite Mineral processing methods Multi Attribute Decision Making Delphi Analytical Hierarchy process (DAHP)Fuzzy TOPSIS
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Simulation of fluid-structure interaction in a microchannel using the lattice Boltzmann method and size-dependent beam element on a graphics processing unit
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作者 Vahid Esfahanian Esmaeil Dehdashti Amir Mehdi Dehrouye-Semnani 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期389-395,共7页
Fluid-structure interaction (FSI) problems in microchannels play a prominent role in many engineering applications. The present study is an effort toward the simulation of flow in microchannel considering FSI. The b... Fluid-structure interaction (FSI) problems in microchannels play a prominent role in many engineering applications. The present study is an effort toward the simulation of flow in microchannel considering FSI. The bottom boundary of the microchannel is simulated by size-dependent beam elements for the finite element method (FEM) based on a modified cou- ple stress theory. The lattice Boltzmann method (LBM) using the D2Q13 LB model is coupled to the FEM in order to solve the fluid part of the FSI problem. Because of the fact that the LBM generally needs only nearest neighbor information, the algorithm is an ideal candidate for parallel computing. The simulations are carried out on graphics processing units (GPUs) using computed unified device architecture (CUDA). In the present study, the governing equations are non-dimensionalized and the set of dimensionless groups is exhibited to show their effects on micro-beam displacement. The numerical results show that the displacements of the micro-beam predicted by the size-dependent beam element are smaller than those by the classical beam element. 展开更多
关键词 fluid-structure interaction graphics processing unit lattice Boltzmann method size-dependentbeam element
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Combing the Entropy Weight Method with Fuzzy Mathematics for Assessing the Quality and Post-Ripening Mechanism of High-Temperature Daqu during Storage
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作者 YANG Junlin YANG Shaojuan +8 位作者 WU Cheng YIN Yanshun YOU Xiaolong ZHAO Wenyu ZHU Anran WANG Jia HU Feng HU Jianfeng WANG Diqiang 《食品科学》 北大核心 2025年第9期48-62,共15页
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar... This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu. 展开更多
关键词 microbial community high-temperature Daqu comprehensive quality evaluation entropy weight method maturation process
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A Distributed Newton Method for Processing Signals Defined on the Large-Scale Networks
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作者 Yanhai Zhang Junzheng Jiang +1 位作者 Haitao Wang Mou Ma 《China Communications》 SCIE CSCD 2023年第5期315-329,共15页
In the graph signal processing(GSP)framework,distributed algorithms are highly desirable in processing signals defined on large-scale networks.However,in most existing distributed algorithms,all nodes homogeneously pe... In the graph signal processing(GSP)framework,distributed algorithms are highly desirable in processing signals defined on large-scale networks.However,in most existing distributed algorithms,all nodes homogeneously perform the local computation,which calls for heavy computational and communication costs.Moreover,in many real-world networks,such as those with straggling nodes,the homogeneous manner may result in serious delay or even failure.To this end,we propose active network decomposition algorithms to select non-straggling nodes(normal nodes)that perform the main computation and communication across the network.To accommodate the decomposition in different kinds of networks,two different approaches are developed,one is centralized decomposition that leverages the adjacency of the network and the other is distributed decomposition that employs the indicator message transmission between neighboring nodes,which constitutes the main contribution of this paper.By incorporating the active decomposition scheme,a distributed Newton method is employed to solve the least squares problem in GSP,where the Hessian inverse is approximately evaluated by patching a series of inverses of local Hessian matrices each of which is governed by one normal node.The proposed algorithm inherits the fast convergence of the second-order algorithms while maintains low computational and communication cost.Numerical examples demonstrate the effectiveness of the proposed algorithm. 展开更多
关键词 graph signal processing distributed Newton method active network decomposition secondorder algorithm
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PREPROCESSING AND POSTPROCESSING SYSTEM FOR FINITE ELEMENT COMPUTATION
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作者 李俊 潘梅园 陈钟鸣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第2期108-112,共5页
This paper discusses some aspects of finite element computation,such as the automatic generation of finite element ,refinement of mesh,process of node density, distribution of load,optimum design and the drawing o... This paper discusses some aspects of finite element computation,such as the automatic generation of finite element ,refinement of mesh,process of node density, distribution of load,optimum design and the drawing of stress contour, and describes the developing process of software for a planar 8 node element. 展开更多
关键词 finite element method optimum design stress CONTOUR preprocessing and post processing load distribution
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SMALL PERTURBATION CRAMER METHODS AND MODERATE DEVIATIONS FOR MARKOV PROCESSES 被引量:2
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作者 高付清 《Acta Mathematica Scientia》 SCIE CSCD 1995年第4期394-405,共12页
This paper presents a small perturbation Cramer method for obtaining the large deviation principle of a family of measures (β,ε> 0) on a topological vector space. As an application, we obtain the moderate deviati... This paper presents a small perturbation Cramer method for obtaining the large deviation principle of a family of measures (β,ε> 0) on a topological vector space. As an application, we obtain the moderate deviation estimations for uniformly ergodic Markov processes. 展开更多
关键词 Large deviations Cramer methods Markov processes moderate deviations.
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ANALYSIS OF THE THERMOPHYSICAL PARAMETERS OF MOIST WOOD PARTICLE MATERIAL IN A COUPLED HEAT AND MASS TRANSFER PROCESS OF FREEZING BY USING FINITE ELEMENT METHOD
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作者 Shang DekuNortheast Forestry University 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1991年第2期69-76,共8页
The coupled heat and moisture transfer in a freezing process of wood particle material was mathematically modeled in the paper. The models were interactively solved by using the numerical method(the finite element met... The coupled heat and moisture transfer in a freezing process of wood particle material was mathematically modeled in the paper. The models were interactively solved by using the numerical method(the finite element method and the finite difference method). By matching the theoretical calculation to an experiment, the nonlinear problem was analyzed and the variable thermophysical parameters concerned was evaluated. The analysis procedure and the evaluation of the parameters were presented in detail. The result of the study showed that by using the method as described in the paper, it was possible to determine the variable (with respect to temperature, moisture content and freezing state) thermophysical parameters which were unknown or difficult to measure as long as the governing equations for a considered process were available. The method can significantly reduces the experiment efforts for determining thermophysical parameters which arc very complicated to measure. The determined variable of the effective heat conductivity of wood particle material was given in the paper. The error of the numerical calculation was also estimated by the comparison with a matched experiment. 展开更多
关键词 Finite element method Freezing process Coupled heat and mass transfer Variable thermophysical parameters
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Compute Unified Device Architecture Implementation of Euler/Navier-Stokes Solver on Graphics Processing Unit Desktop Platform for 2-D Compressible Flows
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作者 Zhang Jiale Chen Hongquan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第5期536-545,共10页
Personal desktop platform with teraflops peak performance of thousands of cores is realized at the price of conventional workstations using the programmable graphics processing units(GPUs).A GPU-based parallel Euler/N... Personal desktop platform with teraflops peak performance of thousands of cores is realized at the price of conventional workstations using the programmable graphics processing units(GPUs).A GPU-based parallel Euler/Navier-Stokes solver is developed for 2-D compressible flows by using NVIDIA′s Compute Unified Device Architecture(CUDA)programming model in CUDA Fortran programming language.The techniques of implementation of CUDA kernels,double-layered thread hierarchy and variety memory hierarchy are presented to form the GPU-based algorithm of Euler/Navier-Stokes equations.The resulting parallel solver is validated by a set of typical test flow cases.The numerical results show that dozens of times speedup relative to a serial CPU implementation can be achieved using a single GPU desktop platform,which demonstrates that a GPU desktop can serve as a costeffective parallel computing platform to accelerate computational fluid dynamics(CFD)simulations substantially. 展开更多
关键词 graphics processing unit(GPU) GPU parallel computing compute unified device architecture(CUDA)Fortran finite volume method(FVM) acceleration
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Assessment of Effects of Green Construction by Analytic Hierarchy Process and Fuzzy Synthetic Judgment Method
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作者 申琪玉 李惠强 《Journal of Southwest Jiaotong University(English Edition)》 2008年第3期260-265,共6页
The index system, code system, and weights of indexes are established to assess the effects of green construction. The index system consists of index level, factor level and sub-factor level. The analytic hierarchy pr... The index system, code system, and weights of indexes are established to assess the effects of green construction. The index system consists of index level, factor level and sub-factor level. The analytic hierarchy process is used to determine the weights of indexes, and the consistency test indicate that the weight assignment is reasonable. Using fuzzy synthetic judgment method, the assessment model is built, which includes factor set, weight set and conclusion set. An example is given to demonstrate the assessment procedures. 展开更多
关键词 Green construction Assessment system Analytic hierarchy process Fuzzy synthetic judgment method
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A Pole Assignment Design Method of Process Control System for Tubular Heat Exchanger
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作者 周清泉 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第4期13-19,共7页
This Paper has first studied the simplified model of tubular heat exchanger which is widely used in the industry and other field.On the basis of reference 2,a new pole assignment design method of pro-cess control syst... This Paper has first studied the simplified model of tubular heat exchanger which is widely used in the industry and other field.On the basis of reference 2,a new pole assignment design method of pro-cess control system with derivative control action is found.For the above system,the method and the for-mation which calculate the feedback matrix K and gain matrix L is given,and the simulation of the system is made. 展开更多
关键词 tubular heat exchanger process control system pole assignment design method feedback matrix Gain matrix
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Label-Free and Real-Time Monitor of Binding and Dissociation Processes between Protein A and Swine IgG by Oblique-Incidence Reflectivity Difference Method
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作者 何立平 刘爽 +6 位作者 戴俊 吴琳 刘国振 韦汉福 吕惠宾 金奎娟 杨国桢 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期35-38,共4页
Life science has a need for detection methods that are label-free and real-time. In this paper, we have selected staphylococcal protein A (SPA) and swine immunoglobulin G (IgG), and monitor the bindings between SP... Life science has a need for detection methods that are label-free and real-time. In this paper, we have selected staphylococcal protein A (SPA) and swine immunoglobulin G (IgG), and monitor the bindings between SPA and swine IgG with different concentrations, as well as the dissociations of SPA-swine IgG complex in different pH values of phosphate buffer by oblique-incidence reflectivity difference (OIRD) in a label-free and real-time fashion. We obtain the ON and OFF reaction dynamic curves corresponding to the bindings and dissociations of SPA and swine IgG. Through our analysis of the experimental results, we have been able to obtain the damping coefficients and the dissociation time of SPA and swine IgG for different pH values of the phosphate buffer. The results prove that the OIRD technique is a competing method for monitoring the dynamic processes of biomolecule interaction and achieving the quantitative information of reaction kinetics. 展开更多
关键词 SPA pH Label-Free and Real-Time Monitor of Binding and Dissociation processes between Protein A and Swine IgG by Oblique-Incidence Reflectivity Difference method IGG
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Analysis of application range of simplified models for field to thermo-field to thermionic emission processes from the cathode
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作者 Li SUN Zhuo DAI +2 位作者 Ming XU Wei WANG Zengyao LI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第9期51-60,共10页
Electron emission plays a dominant role in plasma-cathode interactions and is a key factor in many plasma phenomena and industrial applications.It is necessary to illustrate the various electron emission mechanisms an... Electron emission plays a dominant role in plasma-cathode interactions and is a key factor in many plasma phenomena and industrial applications.It is necessary to illustrate the various electron emission mechanisms and the corresponding applicable description models to evaluate their impacts on discharge properties.In this study,detailed expressions of the simplified formulas valid for field emission to thermo-field emission to thermionic emission typically used in the numerical simulation are proposed,and the corresponding application ranges are determined in the framework of the Murphy-Good theory,which is commonly regarded as the general model and to be accurate in the full range of conditions of the validity of the theory.Dimensionless parameterization was used to evaluate the emission current density of the Murphy-Good formula,and a deviation factor was defined to obtain the application ranges for different work functions(2.5‒5 eV),cathode temperatures(300‒6000 K),and emitted electric fields(10^(5) to 10^(10) V·m^(-1)).The deviation factor was shown to be a nonmonotonic function of the three parameters.A comparative study of particle number densities in atmospheric gas discharge with a tungsten cathode was performed based on the one-dimensional implicit particle-in-cell(PIC)with the Monte Carlo collision(MCC)method according to the aforementioned application ranges.It was found that small differences in emission current density can lead to variations in the distributions of particle number density due to changes in the collisional environment.This study provides a theoretical basis for selecting emission models for subsequent numerical simulations. 展开更多
关键词 electron emission processes application range Murphy-Good theory implicit particlein-cell Monte Carlo collision method
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大型低温火箭准时发射技术研究与空间站应用
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作者 钟文安 余秀伟 +3 位作者 叶欣 晏政 陈少将 宋扬 《宇航学报》 北大核心 2025年第2期378-388,共11页
空间站建造中的交会对接任务对运载火箭提出了“零窗口”准时发射要求。大型低温液体火箭发射流程复杂,影响准时发射的因素众多,使得准时发射能力长期难以被定量描述,发射任务难度极大。为了提高运载火箭的准时发射能力,研究了准时发射... 空间站建造中的交会对接任务对运载火箭提出了“零窗口”准时发射要求。大型低温液体火箭发射流程复杂,影响准时发射的因素众多,使得准时发射能力长期难以被定量描述,发射任务难度极大。为了提高运载火箭的准时发射能力,研究了准时发射的概念和技术原理,提出了发射准时度来量化描述火箭的准时发射能力。以空间站建造发射任务为对象,根据准时发射技术原理对火箭的加注发射流程进行优化,并将零窗口拓展为窄窗口。利用蒙特卡罗方法分别对优化前后的流程进行仿真,结果表明:流程优化后发射准时度提高了0.214,验证了准时发射技术的有效性。准时发射技术已成功应用于空间站建造的发射任务中,有力保障了空间站建造任务的圆满成功。 展开更多
关键词 发射准时度 加注发射流程 零窗口 蒙特卡罗方法
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液压冷榨大豆饼粕蛋白提取工艺优化及其应用现状分析
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作者 蒋林斌 黄广君 《中国调味品》 北大核心 2025年第3期125-128,共4页
随着消费者对植物蛋白的需求不断增加,在植物蛋白市场中,大豆蛋白由于其营养价值和功能特性而被广泛应用。然而,工业生产的大豆饼粕中含有机溶剂,严重制约着大豆蛋白在绿色食品和有机食品领域中的应用。大豆的压榨方式主要为螺旋压榨法... 随着消费者对植物蛋白的需求不断增加,在植物蛋白市场中,大豆蛋白由于其营养价值和功能特性而被广泛应用。然而,工业生产的大豆饼粕中含有机溶剂,严重制约着大豆蛋白在绿色食品和有机食品领域中的应用。大豆的压榨方式主要为螺旋压榨法和液压冷榨压榨法,两种压榨方法对大豆饼粕中蛋白的品质均会产生影响。该研究基于此,对比螺旋压榨法和液压冷榨压榨法对大豆饼粕蛋白提取率和品质的影响,最终确定采用液压冷榨压榨法压榨大豆,获得的大豆饼粕中蛋白提取率和品质均更高。以液压冷榨压榨法压榨的大豆饼粕为原材料,对其蛋白和脂质的提取工艺进行研究和优化。结果表明,最佳的大豆饼粕蛋白和脂质提取工艺为pH值10、提取时间45 min和料液比例1∶20。 展开更多
关键词 液压冷榨法 大豆蛋白 副产物 工艺优化
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超声辅助酶法提取咖啡果皮花青素工艺优化及其体外抗氧化活性评价
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作者 李学玲 李雪 +3 位作者 任四妹 许苑南 郭洁 杨莉 《中国酿造》 北大核心 2025年第2期251-255,共5页
为探究咖啡果皮花青素的提取工艺和体外抗氧化能力,该研究采用超声辅助酶法提取咖啡果皮花青素,通过单因素试验及正交试验对咖啡果皮花青素提取工艺进行优化,并研究其体外抗氧化活性。结果表明,咖啡果皮花青素最佳提取工艺条件为:提取温... 为探究咖啡果皮花青素的提取工艺和体外抗氧化能力,该研究采用超声辅助酶法提取咖啡果皮花青素,通过单因素试验及正交试验对咖啡果皮花青素提取工艺进行优化,并研究其体外抗氧化活性。结果表明,咖啡果皮花青素最佳提取工艺条件为:提取温度60℃、乙醇体积分数60%、果胶酶添加量2%、料液比1∶50(g∶mL)、提取时间40 min。在此优化条件下,咖啡果皮花青素得率达0.274%。体外抗氧化试验结果表明,当样品质量浓度为30μg/mL时,其对DPPH、OH自由基的清除率最佳,分别为91.40%、67.28%,半抑制浓度(IC50)值分别为6.36μg/mL、12.16μg/mL;当样品质量浓度为5μg/mL时,总还原能力最高(吸光度值为0.987)。因此,咖啡果皮花青素具有一定的抗氧化能力。 展开更多
关键词 咖啡果皮 花青素 超声辅助酶法 提取工艺 体外抗氧化活性
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基于模糊层次分析的致密气储层广义平面阻流带识别
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作者 赖枫鹏 李彬册 +1 位作者 任广磊 张伟 《中国海上油气》 北大核心 2025年第1期129-138,共10页
致密气储层具有物性条件差、非均质性强、含水饱和度高等特点,储层中存在流体渗流受限区域,使得气井产量和控制储量受到影响。一般意义上的阻流带强调的是沉积、成岩作用,以及砂体边界发育等静态地质因素对生产的影响,缺少气水两相渗流... 致密气储层具有物性条件差、非均质性强、含水饱和度高等特点,储层中存在流体渗流受限区域,使得气井产量和控制储量受到影响。一般意义上的阻流带强调的是沉积、成岩作用,以及砂体边界发育等静态地质因素对生产的影响,缺少气水两相渗流过程中不同因素产生的动态阻流表征。首先明确了致密气储层广义平面阻流带的内涵,提出了从生产特征、储层特征和两相共渗特征三个方面进行分析。基于模糊层次分析法,建立了广义平面阻流带层次结构模型和综合评价指标(GI),以鄂尔多斯盆地某致密气藏井区为例,计算了不同因素的影响权重值,得到GI数值,通过插值绘制了研究区广义平面阻流带发育图。进一步对比研究了高产、中产、低产三类井无量纲产气量和无量纲产量递减率与GI数值的关系,结果表明:无量纲产气量与GI值呈负相关关系,无量纲产量递减率与GI值呈正相关关系。利用广义平面阻流带发育图可以为后续气井工作制度的优化调整提供科学支撑。 展开更多
关键词 致密气 广义平面阻流带 评价指标 识别方法 模糊层次分析 权重计算
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基于帧间特征点匹配的流速测量模型研究
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作者 刘明堂 张浩 《水利水电快报》 2025年第3期116-123,共8页
图像法在流速测量领域越发重要,提出了基于帧间特征点匹配的流速测量模型,在试验模型上进行了验证,并在黄河濮阳范县段进行了应用。对加速稳健特征(Speeded Up Robust Features,SURF)算法与暴力匹配(Brute Force,BF)算法进行改进,根据... 图像法在流速测量领域越发重要,提出了基于帧间特征点匹配的流速测量模型,在试验模型上进行了验证,并在黄河濮阳范县段进行了应用。对加速稳健特征(Speeded Up Robust Features,SURF)算法与暴力匹配(Brute Force,BF)算法进行改进,根据图像中的轮廓信息对河道区域进行分割,使得SURF算法的识别区域与识别结果更精准,识别速度更快。然后,根据特征点间的欧氏距离筛选特征点,计算出特征点的像素位移,根据帧速率计算得到特征点的像素速度并将其转化为实际速度。结果表明:与多普勒流速仪测量结果进行对比,所提算法测量结果的平均绝对误差为0.56 cm/s,平均相对误差为5.7%;与LK光流法相比,分别提高了0.3 cm/s与4.1%。该算法应用于黄河濮阳范县段的分析结果表明:平均相对误差为4.24%,比LK光流法提高了4.15%。基于帧间特征点匹配的流速测量模型在保证测量精度的情况下,能兼顾流速测量的实时性与便捷性,满足对河流流速实时、准确、便捷的测量要求。 展开更多
关键词 流速测量 智能检测 图像法 帧间特征点图像处理
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