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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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FREE VIBRATION ANALYSIS AND PHYSICAL PARAMETER IDENTIFICATION OF NON-UNIFORM BEAM CARRYING SPRING-MASS SYSTEMS 被引量:1
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作者 马蕾 芮筱亭 +2 位作者 Abbas Laith 杨富锋 张建书 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第4期345-353,共9页
To analyze a multibody system composed of non-uniform beam and spring-mass subsystems, the model discretization is carried on by utilizing the finite element method(FEM), the dynamic model of non-uniform beam is dev... To analyze a multibody system composed of non-uniform beam and spring-mass subsystems, the model discretization is carried on by utilizing the finite element method(FEM), the dynamic model of non-uniform beam is developed by using the transfer matrix method of multibody system(MS-TMM), the transfer matrix of non-u- niform beam is derived, and the natural frequencies are computed. Compared with the numerical assembly method (NAM), the results by MS-TMM have good agreement with the results by FEM, and are better than the results by NAM. When using the high precision method, the global dynamic equations of the complex multibody system are not needed and the orders of involved system matrices are decreased greatly. For the investigation on the re- verse problem of the physical parameter identification of multibody system, MS-TMM and the optimization tech- nology based on genetic algorithms(GAs) are combined and extended. The identification problem is exchanged for an optimization problem, and it is formulated as a global minimum solution of the objective function with respect to natural frequencies of multibody system. At last, the numerical example of non-uniform beam with attach- ments is discussed, and the identification results indicate the feasibility and the effectivity of the proposed aop- proach. 展开更多
关键词 non-uniform beam physical parameter identification natural frequency transfer matrix method multibody system genetic algorithms
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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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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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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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Research of Physical Parameter Identification and Damage Localization based on the Gibbs Sampling
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作者 Ziyan Wu Zongming Cai Shukui Liu 《建筑工程(中英文版)》 2017年第1期1-6,共6页
A new method for structural physical parameter identification is proposed for linear structure.Firstly,a linear structural identification model was obtained based on a series of transformation of the dynamic character... A new method for structural physical parameter identification is proposed for linear structure.Firstly,a linear structural identification model was obtained based on a series of transformation of the dynamic characteristic equation.Then the posterior distribution of the model is obtained by the Bayesian updating theory.Using the structural modal parameters and considering their randomness,the structural stiffness parameter is obtained from the conditional posterior distribution of the linear structural identification model.The Gibbs sampling based on the Markov Chain Monte Carlo(MCMC)method is employed during the process.In order to illustrate the proposed method,a 3-DOF linear shear building is used as an example to detect and quantify its damage based on model data measured before and after a severe loading event.The research shows that damage level and locations can be identified with little error by using proposed method. 展开更多
关键词 physical PARAMETERS identification DAMAGE LOCALIZATION MCMC method Gibbs Sampling
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Systematic Evaluation of Pharmacognostic Identification of Polygonum capitatum 被引量:1
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作者 Bo TU Xu ZHANG +3 位作者 Minghui HE Shanggao LIAO Yongqin ZENG Yan LIN 《Medicinal Plant》 CAS 2023年第4期9-13,共5页
[Objectives] To investigate the systematic evaluation of pharmacognostic identification of Polygonum capitatum . [Methods] 10 batches of P. capitatum cultivated in Guizhou were chosen for plant samples. Macroscopical ... [Objectives] To investigate the systematic evaluation of pharmacognostic identification of Polygonum capitatum . [Methods] 10 batches of P. capitatum cultivated in Guizhou were chosen for plant samples. Macroscopical identification was conducted on plant roots, stems, leaves, flowers and fruits. The P. capitatum powder was processed for physical and chemical distinction by FeCl 3 chromogenic reaction, hydrochloric acid magnesium powder reaction, AlCl 3 color development reaction and thin-layer chromatography.Microscope identification was carried out on the powder. Plant genome DNeasy Plant Kit was adopted for DNA molecular marker identification. [Results] The results showed that the stem of P. capitatum was tufted, the leaves were oval, 2 to 5 cm long, and 1 to 2 cm wide;the leaf apex was acute and cuneate at the base, the inflorescence was capitate, paired or solitary;the raceme was erect and nearly spherical, and the perianth was light red. Furthermore, for the chromogenic reaction of FeCl 3 ethanol extract of P. capitatum , appeared blue and turned to dark blue after long time storing at room temperature. For the reaction of hydrochloric acid magnesium powder, the alcohol extract of P. capitatum , exhibited deep red. In the color reaction of AlCl 3, the alcohol extract revealed yellow fluorescence under 360 nm UV lamp. Microscope identification of the powder displayed pollen grains, crystal sheath fibers, cellulose, vessels, starch grains, cork cells, and other characteristic fragments. In addition, DNA barcoding electrophoresis results showed that P. capitatum showed a clear and bright single band near 500 bp, and further sequencing results showed that the sequence differences were mainly concentrated in ITS1 and ITS2 region. [Conclusions] Systematic evaluation for the identification of P. capitatum is established, which combines with macroscopic identification, physicochemical identification, powder microscope identification, and DNA molecular identification. Finally, the original medicinal material is identified as P. capitatum Buch.-Ham. ex D. Don. 展开更多
关键词 Chinese herbal medicine Polygonum capitatum Pharmacognostic identification Character identification physical and chemical identification Microscopic identification DNA molecular marker identification
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Different Methods of Analysis for the Identification of Materials Dated to Different Periods in Egypt
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作者 Safaa Abd El Salam 《Journal of Physical Science and Application》 2011年第2期85-99,共15页
Different questions may be raised during the course of analysis concerning in particular the characterization of materials used, their preparation and application techniques. The different methods used to identify the... Different questions may be raised during the course of analysis concerning in particular the characterization of materials used, their preparation and application techniques. The different methods used to identify the materials of mud brick, limestone, plaster, mortar and pigments, collected from different sites and periods from Egypt, in order to identify and characterize the materials, their structure, composition and their mineralogical compounds were: (Op) optical microscopy, which was used to examine and to identify the materials structures. Methods used in initial examination were: (1) (MCA): Micro-chemical analysis, to identify the nature of the materials and for water-soluble salts, to identify sulphates, chlorides, carbonates, nitrites and nitrates; (2) (SM): Standard methods of wet chemical analysis were used to identify the quantitative and qualitative nature of the, mud building, mortars and their mixtures; (3) (SEM & EDS): Analytical scanning electron microscope with energy dispersive X-ray analysis system was used to examine the micro-morphology and determine the chemical composition of the different materials; (4) (XRD & XRPD): X-ray diffraction to identify the mineralogical compound of the plaster, limestone, mortars and pigments used. From all the results obtained, it was possible to establish the nature of the mortars and their binders as well as some other inclusion. In addition to the identification of the stratigraphy of the layers applied in some samples, the examination and analysis gave details of the materials and the approximate ratio of the amount of additives used. Furthermore, the mineralogical analysis provided information on the main mineralogical phases present in the materials analyzed from the different periods. 展开更多
关键词 Characterization different materials chemical and physical methods.
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Binding Media: Methods of Identification: Part 1, Theoretical Work
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作者 Safaa Ahmed Abd El Salam 《Journal of Physical Science and Application》 2011年第3期204-215,共12页
The identification of binding media presents a major difficulty in the investigation of painting techniques. The materials used in ancient times as a media for the pigments were varied, such as glues, gums and egg whi... The identification of binding media presents a major difficulty in the investigation of painting techniques. The materials used in ancient times as a media for the pigments were varied, such as glues, gums and egg white. These adhesives were mixed with the pigments to adhere to the surface or to prepare the ground. This medium serves to protect the pigments more or less perfectly, from chemical and mechanical injury. Binding media determines the technique of painting. Artists' techniques used through the centuries differ more in the binding media than in the pigments used. They are all organic substances containing the same common elements, and in the small samples which can be removed from paintings, occur only in micro quantities, moreover, binding media undergo considerable degradation over long periods of time. In the examination of works of art, only very small specimens can be taken and, the proportion of binding medium to pigment being small, sensitive methods of analysis have to be adopted in an attempt to detect and identify the medium that may have been used. On the other hand, the use of such methods possesses the disadvantage that impurities present in the painting materials may also be detected and may lead to erroneous conclusions. There is no general microanalysis technique existed in the identification of binding media, and the materials commonly used as media are highly complex compared with the simple inorganic compounds employed as pigments. However, several methods can be used in the identification of binding media such as micro-chemical, chemical and physical methods. 展开更多
关键词 Painting media chemical physical methods
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Separation and Preliminary Identification of Intestinal Probiotics of Laying Hens
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作者 Guo Shijin Zhang Zhimei +4 位作者 Fu Shijun Mo Ling Zhang Ying Shen Zhiqiang Huang Baohua 《Animal Husbandry and Feed Science》 CAS 2018年第1期72-74,共3页
[Objective] The paper was to isolate and identify probiotics in the intestine of laying hens. [Method] The intestinal probiotics in laying hens at peak period were isolated using conventional separation methods; the p... [Objective] The paper was to isolate and identify probiotics in the intestine of laying hens. [Method] The intestinal probiotics in laying hens at peak period were isolated using conventional separation methods; the physical and chemical properties of target strains and in vitro antibacterial effects were measured. Moreover, the safety test of chicks was conducted. [Result] Four strains of lactobacillus were isolated from the jejunum of laying hens, including Lactobacillus plantarum, Bacillus acidophilus, L. delbrueckii subsp. Delbrueckii and L. delbrueckii subsp. Lactis, and their inhibition zone diameters were 18.30, 16.07, 11.45, 17.26 mm, respectively. One strain of Lactobacillus, L. brevis, was isolated from the cecum, with the inhibition zone diameter of 10.26 mm. Three strains of bacillus were isolated from the cecum, including Bacillus subtilis, B. cereus and B. licheniformis, and their inhibition zone diameters were 9.25, 8.46 and 8.37 mm, respectively. Daily drinking 2 billion units of viable bacteria was the safe dosage for chicks. [Conclusion] Eight strains of probiotics had certain inhibitory effect on Escherichia coli O;, and had no toxic side effects to chicks. Lactobacillus had strong antibacterial effect on E. coli O;, while the antibacterial effect of bacillus was relatively weak. 展开更多
关键词 Laying hen Intestine Probiotics Isolation identification physical and chemical properties Antibacterial Safety test
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复合助剂对低温喷雾干燥蓝靛果粉理化性质的影响 被引量:2
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作者 郑先哲 鲁天麟 +5 位作者 陈启明 张雨涵 沈柳杨 付科森 朱海辉 柏才宇 《农业工程学报》 EI CAS CSCD 北大核心 2024年第2期93-106,共14页
为保证低温喷雾干燥后蓝靛果粉品质,采用黄金分割法研究复合助剂(麦芽糊精、β-环糊精和乳清蛋白)对喷雾干燥蓝靛果粉理化性质的影响,分析低温进风温度(50~90℃)对蓝靛果粉花青素保留率、集粉率和含水率的影响规律。结果表明,在麦芽糊... 为保证低温喷雾干燥后蓝靛果粉品质,采用黄金分割法研究复合助剂(麦芽糊精、β-环糊精和乳清蛋白)对喷雾干燥蓝靛果粉理化性质的影响,分析低温进风温度(50~90℃)对蓝靛果粉花青素保留率、集粉率和含水率的影响规律。结果表明,在麦芽糊精、β-环糊精的质量比例为85.4%、14.6%时,集粉率高达37.96%;随进料溶液中麦芽糊精质量比例增加,蓝靛果粉玻璃化转变温度、水溶性指数、堆积密度、亮度L^(*)值、红度a^(*)值和色差值ΔE呈增加趋势,含水率、花青素含量和黄度b^(*)值呈下降趋势;在麦芽糊精、β-环糊精和乳清蛋白质量比例为72.9%、12.5%、14.6%时,集粉率达到最高(40.11%);随料液中乳清蛋白质量比例增加,蓝靛果粉含水率、花青素含量呈上升趋势,其玻璃化转变温度、水溶性指数、亮度L^(*)值、红度a^(*)值、黄度b^(*)值和色差值ΔE等指标呈下降趋势;复合助剂显著提高蓝靛果粉集粉率(P<0.05),对其中的花青素起到较强保护作用,其含水率、水溶性指数、堆积密度等理化指标均接近于最优水平。低温喷雾干燥研究发现,随进风温度上升,集粉率和含水率呈负相关,在进风温度90℃时,集粉率最高的配方中可实现较高花青素保留率(89.94%)。低频核磁共振波谱以及质子密度图像信息分析表明,加入的助剂与蓝靛果果汁中水分通过氢键、静电结合力和疏水作用等分子间作用力,形成稳定性高水合物、增强液滴聚结抵抗力,提高料液玻璃态转换温度,从而实现高集粉率和高花青素保留率的蓝靛果果粉低温喷雾干燥;红外光谱分析表明,复合助剂可在蓝靛果果粉中形成分子间氢键,并对花青素等活性物质进行固定包埋保护。研究结果可为蓝靛果粉喷雾干燥加工生产提供理论支撑和参考依据。 展开更多
关键词 干燥 理化特性 低温喷雾干燥 复合助剂 蓝靛果 黄金分割法 花青素 核磁共振
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关苍术亲脂性化学成分研究
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作者 周媛媛 孙杰 +5 位作者 江冰悦 杨咏琪 董柯杉 王萍 方振兴 张晓娟 《中医药信息》 2024年第1期32-35,43,共5页
目的:研究关苍术亲脂性成分的化学成分。方法:使用硅胶柱色谱、Sephadex LH-20柱色谱、中压液相色谱和半制备HPLC等方法对关苍术中的化学成分进行分离纯化,并通过理化性质和MS与NMR等波谱技术对其化学成分进行结构鉴定。结果:从关苍术... 目的:研究关苍术亲脂性成分的化学成分。方法:使用硅胶柱色谱、Sephadex LH-20柱色谱、中压液相色谱和半制备HPLC等方法对关苍术中的化学成分进行分离纯化,并通过理化性质和MS与NMR等波谱技术对其化学成分进行结构鉴定。结果:从关苍术药材中分离并鉴定了12种化合物,分别鉴定为osthol(1)、Atractylochromene(2)、6,7-二羟基-8-甲氧基香豆素(3)、8-羟基-6,7-二甲氧基香豆素(4)、7-甲氧基香豆素(5)、豆甾-4-烯-3-酮(6)、蒲公英萜醇乙酸酯(7)、白术内酯Ⅱ(8)、白术内酯Ⅰ(9)、桉叶-4(15)-烯-7β,11-二醇(10)、反式对羟基桂皮酸甲酯(11)、丁香醛(12)。结论:化合物1,3~6,10~12为首次从关苍术中分离的化合物。 展开更多
关键词 关苍术 化学成分 理化性质 分离鉴定 结构鉴定
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压热及酶解脱支处理对莲藕淀粉品质的影响
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作者 王青 朱双全 +4 位作者 周庆新 李晓红 张丰香 李美蓉 孙金月 《山东农业科学》 北大核心 2024年第6期120-127,共8页
淀粉是莲藕的主要成分。本研究通过压热处理、酶解脱支处理进行莲藕淀粉改性,并对其品质进行比较。结果发现:改性后莲藕淀粉中直链淀粉与碘结合能力显著增强,其中普鲁兰酶脱支处理莲藕淀粉(ELRS)的碘结合力最高,即可溶性直链淀粉含量最... 淀粉是莲藕的主要成分。本研究通过压热处理、酶解脱支处理进行莲藕淀粉改性,并对其品质进行比较。结果发现:改性后莲藕淀粉中直链淀粉与碘结合能力显著增强,其中普鲁兰酶脱支处理莲藕淀粉(ELRS)的碘结合力最高,即可溶性直链淀粉含量最高;水合能力显著增强,其中压热法处理莲藕淀粉(HLRS)的持水性、持油性和膨胀度(21.766%)最高,析水率(14.300%)最低;压热后普鲁兰酶脱支处理莲藕淀粉(HELRS)的溶解度(63.555%)、透明度(0.717%)最高;改性后莲藕淀粉的糊化起始温度(T0)、热焓值(ΔH)、糊化温度(ΔT)均有所下降,其中HELRS的ΔH最低,表明改性后熔解莲藕淀粉所需的能量减少;检测改性后淀粉的凝胶特性表明,莲藕淀粉的硬度、弹性、内聚性、粘性和回弹性均有所下降。该研究结论为食品生产中针对不同需求进行淀粉改性提供了理论依据,并为莲藕淀粉的高附加值产品开发提供指导。 展开更多
关键词 莲藕淀粉 压热法 酶解脱支处理 理化性质
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阴道环体外理化评价方法研究进展
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作者 李莉 黄元礼 +1 位作者 赵丹妹 柯林楠 《中国药事》 CAS 2024年第10期1213-1221,共9页
目的:研究分析阴道环体外理化评价方法的研究进展和应用情况,并对存在的问题进行探讨,为我国该类产品的质量控制和科学监管提供参考。方法:梳理国内外阴道环研发和上市产品现状,对体外理化评价方法如药物释放测试、机械性能测试等进行... 目的:研究分析阴道环体外理化评价方法的研究进展和应用情况,并对存在的问题进行探讨,为我国该类产品的质量控制和科学监管提供参考。方法:梳理国内外阴道环研发和上市产品现状,对体外理化评价方法如药物释放测试、机械性能测试等进行总结和分析。结果:阴道环作为一种新型药械组合产品,目前国内外缺乏该类产品体外理化评价的标准方法。结论:阴道环在艾滋病预防及妇科疾病的治疗方面展现出巨大的应用前景,由于其具备药品和器械双重特点,决定了其质量控制和评价手段不能单纯地按照药品的相关要求来进行,亟需开展阴道环体外评价试验方法标准化的相关研究。 展开更多
关键词 阴道环 药械组合产品 体外理化评价方法 药物释放
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不同研磨方式对小米粉理化特性的影响
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作者 李苏红 邓超群 +5 位作者 代增君 王晓颖 刘鹏 岳佳豪 赵起越 李拖平 《沈阳农业大学学报》 CAS CSCD 北大核心 2024年第1期47-53,共7页
小米与大米、玉米和小麦等其他谷物相比具有优越的营养特性,是组成现代食品多样化中重要的一部分。为了研究不同研磨方法对小米粉理化性质的影响,分别采用直接粉碎、球磨以及湿磨的方法对原料进行处理,用Mastersize 2000激光粒度仪检测... 小米与大米、玉米和小麦等其他谷物相比具有优越的营养特性,是组成现代食品多样化中重要的一部分。为了研究不同研磨方法对小米粉理化性质的影响,分别采用直接粉碎、球磨以及湿磨的方法对原料进行处理,用Mastersize 2000激光粒度仪检测3种处理方式下小米粉的粒径,分析小米粉的散落性,并利用快速黏度分析仪(RVA)分析3种处理下小米粉的糊化特性。结果表明:3种研磨方式所获得的小米粉粒径差异显著,其中湿磨处理方式得到的小米粉平均粒径最小,为19.88μm,直接粉碎制得小米粉的平均粒径最大,为34.424μm。3种研磨方式中湿磨处理后的小米粉休止角最小,但滑角无明显变化。小米粉的堆积密度和持油性受其粒径大小影响并与其成反比关系。而滑角、休止角和持水性则随小米粉粒径减小先增大后减小。不同研磨方式获得的小米粉颜色略有差异,其中球磨和湿磨制得小米粉L*值较高。不同研磨方式处理的小米粉糊化特性存在差异。RVA分析结果显示,与直接粉碎、球磨相比,湿磨小米粉具有更高的峰值黏度。综上可见,湿磨在加工过程中可以减小小米粉粒径,使淀粉颗粒损伤较小,理化性质变化较小,对小米加工食品产业发展具有重要意义。 展开更多
关键词 研磨方式 小米粉 理化性质
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护肤类化妆品功效评价理化试验方法的现状和分析
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作者 顾宇翔 周羽 刘恕 《日用化学工业(中英文)》 CAS 北大核心 2024年第6期727-732,共6页
根据《化妆品功效宣称评价规范》的规定,实验室试验的结果可以用于支撑多类的化妆品功效宣称。实验室试验包括多种,其中以物理、化学或生物化学的方式进行测试的理化法虽然可能难以准确外推到人体实际使用的效果,但是具有结果重复性较... 根据《化妆品功效宣称评价规范》的规定,实验室试验的结果可以用于支撑多类的化妆品功效宣称。实验室试验包括多种,其中以物理、化学或生物化学的方式进行测试的理化法虽然可能难以准确外推到人体实际使用的效果,但是具有结果重复性较好、方法简单、费用便宜等优点,被广泛使用于抗皱、舒缓、保湿功效评价以及量化指标测试等方面。所用的方法包括抑制基质金属蛋白酶法、抑制弹性蛋白酶法、抑制非酶糖基化反应法、自由基清除法、抑制透明质酸酶法、称重法和持妆(防水抗汗)法等。但目前理化测试方法存在着覆盖面不广、方法使用存在局限性、检测结果支撑功效宣称不恰当、缺乏统一标准等问题,因而现有方法的应用存在不科学的地方。今后建议加强理化试验方法的标准制订,完善化妆品功效评价标准化体系。 展开更多
关键词 化妆品 功效 理化试验方法 现状 护肤
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真空微波干燥对草莓脯品质的影响 被引量:1
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作者 何茸茸 牛丽影 +6 位作者 李大婧 张钟元 唐冬妹 刘春菊 肖亚冬 聂梅梅 肖丽霞 《食品工业科技》 CAS 北大核心 2024年第16期64-72,共9页
为了研究真空环境下不同微波干燥条件对草莓脯质地和营养品质的影响,本文以热风干燥为对照,对3种真空微波处理条件(2.5 w/g-1.5 h、3.5 w/g-1 h、4.5 w/g-0.5 h)获得的草莓脯的水分迁移特性、质构特性、微观结构、色泽及花色苷和酚类物... 为了研究真空环境下不同微波干燥条件对草莓脯质地和营养品质的影响,本文以热风干燥为对照,对3种真空微波处理条件(2.5 w/g-1.5 h、3.5 w/g-1 h、4.5 w/g-0.5 h)获得的草莓脯的水分迁移特性、质构特性、微观结构、色泽及花色苷和酚类物质进行了测定。结果显示,真空微波干燥将草莓脯干燥至含水量20%±2%所需时间显著低于热风,微波功率越大,干燥时间越短。另外,干燥后获得的草莓脯中水分主要呈现结合水与不易流动水2种状态。真空微波干燥获得草莓脯的弛豫时间T2随微波功率增加而增大,说明水分自由度增加;横截面显微观察发现,真空微波干燥使细胞壁发生破裂,微波功率越大,裂隙形成部位越靠近髓芯,裂隙越大,孔隙率越小,而热风干燥的样品细胞完整性、孔隙率高于微波干燥。另外,真空微波干燥的草莓脯硬度、粘力、a^(*)值均低于热风干燥的样品,但L^(*)值、总糖、花青素以及酚类物质的含量均较高。综上所述,真空微波干燥具有更高的干燥效率,并能更好保留草莓脯中花色苷等营养物质。 展开更多
关键词 草莓脯 干燥 真空微波 理化品质
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环境中微塑料检测分析方法研究进展 被引量:2
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作者 万青云 黄燕平 +4 位作者 秦嘉 蓝公仆 安林 谭海曙 许景江 《环境监测管理与技术》 CSCD 北大核心 2024年第2期1-6,共6页
概述了目前较为常见的微塑料检测方法,包括目检法、光谱分析法和热分析法,归纳分析了各种方法的技术进展、研究成果及优缺点,指出微塑料形状、大小、聚合物种类等方面的定性、定量分析尤为重要,能够为微塑料污染防治、溯源和影响评估提... 概述了目前较为常见的微塑料检测方法,包括目检法、光谱分析法和热分析法,归纳分析了各种方法的技术进展、研究成果及优缺点,指出微塑料形状、大小、聚合物种类等方面的定性、定量分析尤为重要,能够为微塑料污染防治、溯源和影响评估提供依据。通过对现有方法的调研总结,提出多种检测分析方法联用将成为研究微塑料的发展方向,未来仍需要改进现有技术或者开发新的检测方法,结合图像处理、深度学习、计算机视觉等手段,缩短识别时间,提高检测精度,进而为微塑料污染防治工程提供技术支撑。 展开更多
关键词 微塑料 检测方法 物理表征 化学分析 环境污染
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氢氧化镁阻燃剂的制备工艺研究进展与发展趋势 被引量:1
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作者 曾书航 李智力 +3 位作者 陈红兵 安建平 廖杰 何东升 《精细石油化工》 CAS 2024年第1期60-64,共5页
介绍了氢氧化镁(MH)阻燃剂的应用特点和作用机理,综述了MH阻燃剂的制备方法,包括物理粉碎法和化学合成法(固相法、气相法、液相法),着重介绍了液相法中的直接沉淀法、溶剂热及水热法、沉淀-共沸蒸馏法、超声化学法和微波辅助法。结合MH... 介绍了氢氧化镁(MH)阻燃剂的应用特点和作用机理,综述了MH阻燃剂的制备方法,包括物理粉碎法和化学合成法(固相法、气相法、液相法),着重介绍了液相法中的直接沉淀法、溶剂热及水热法、沉淀-共沸蒸馏法、超声化学法和微波辅助法。结合MH阻燃剂的工业应用特点,从微细纳米化、表面改性、多种制备工艺融合化研究、复合协同化和固体废弃物制备MH等5个方面对MH阻燃剂的未来发展趋势进行了展望。 展开更多
关键词 氢氧化镁 阻燃 制备方法 研究进展 发展趋势 物理粉碎法 化学合成法
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壳聚糖的改性研究进展及其应用 被引量:1
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作者 丁兆坤 郭荣辉 《纺织科学与工程学报》 CAS 2024年第1期68-74,共7页
壳聚糖被发现以来存在极大的优势,是一种可被修饰的自然生物聚合物。因为其具有丰富的官能团,在功能材料中被广泛应用。简要综述壳聚糖及其改性材料的最新进展,重点详述其物理、化学和生物等改性方法并得到功能材料。其改性功能材料在... 壳聚糖被发现以来存在极大的优势,是一种可被修饰的自然生物聚合物。因为其具有丰富的官能团,在功能材料中被广泛应用。简要综述壳聚糖及其改性材料的最新进展,重点详述其物理、化学和生物等改性方法并得到功能材料。其改性功能材料在水处理、食品加工、制药/生物医学、纺织和农业等领域展示出优异的应用性能。最后,作了简短总结展望,其改性研究和应用仍有更大的探索前景。 展开更多
关键词 壳聚糖 壳聚糖应用 物理法 化学法 生物法
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