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Study of Total Process Energy Integration
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作者 俞红梅 姚平经 袁一 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1999年第2期182-188,共7页
The energy utilization consistency method in process integration extracts the key component of process energy utilization, and simplifies the procedure of process analysis and integration. The method allows the conver... The energy utilization consistency method in process integration extracts the key component of process energy utilization, and simplifies the procedure of process analysis and integration. The method allows the conversion of the total process energy integration into a synthesis problem of a pseudo-heat exchanger network. The advantages of using the energy utilization consistency and the pseudo-temperature methods are presented by two examples of integration of large-scale complex processes. The improved genetic algorithm is proved to be an effective tool in the retrofitting procedures. 展开更多
关键词 total process energy integration global optimization synthesis of heat exchanger net-works ethylene process
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Existence of spontaneous symmetry breaking in two-lane totally asymmetric simple exclusion processes with an intersection 被引量:1
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作者 Bo Tian Ping Xia +2 位作者 Li Liu Meng-Ran Wu Shu-Yong Guo 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第5期182-187,共6页
We study two-lane totally asymmetric simple exclusion processes(TASEPs)with an intersection.Monte Carlo simulations show that only symmetric phases exist in the system.To verify the existence of asymmetric phases,we c... We study two-lane totally asymmetric simple exclusion processes(TASEPs)with an intersection.Monte Carlo simulations show that only symmetric phases exist in the system.To verify the existence of asymmetric phases,we carry out a cluster mean-field analysis.Analytical results show that the densities of the two upstream segments of the intersection site are always equal,which indicates that the system is not in asymmetric phases.It demonstrates that the spontaneous symmetry breaking does not exist in the system.The density profiles and the boundaries of the symmetric phases are also investigated.We find that the cluster mean-field analysis shows better agreement with simulations than the simple mean-field analysis where the correlation of sites is ignored. 展开更多
关键词 spontaneous symmetry breaking cluster mean-field analysis simple mean-field analysis totally asymmetric simple exclusion process(TASEP)
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Extraction Process and Content Determination of Total Flavonoids in Ginkgo( Ginkgo biloba L. ) Leaves 被引量:2
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作者 Dengfeng ZOU Hua ZHU +1 位作者 Binghua QIN Xiaohua WANG 《Agricultural Biotechnology》 CAS 2019年第1期171-175,共5页
[Objectives]This study was conducted to study the extraction process and the content determination of flavonoids in ginkgo( Ginkgo biloba L.) leaves.[Methods]Ethanol extraction and methanol extraction of total flavono... [Objectives]This study was conducted to study the extraction process and the content determination of flavonoids in ginkgo( Ginkgo biloba L.) leaves.[Methods]Ethanol extraction and methanol extraction of total flavonoids in ginkgo leaves were studied,and the optimal extraction conditions for flavonoids were determined by orthogonal test; and with quercetin as reference substance,total flavonoid content in ginkgo leaves was determined by UV spectrophotometry.[Results]The optimal extraction process was 4 h of Soxhlet extraction with methanol; and the total flavonoid contents had a good linear relation in the range of 0. 006 5-0. 039 mg/ml( R^2= 0. 999 9),the average content was stabilized at 1. 135%,and the average recovery of the method was 102. 0%. [Conclusions]This study selected the optimal extraction process for total flavonoids in ginkgo leaves. The test method is simple with high accuracy and precision,and is suitable for the extraction and determination of total flavonoids in ginkgo leaves. 展开更多
关键词 GINKGO biloba L. total FLAVONOIDS EXTRACTION process Content determination
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Optimization of Extraction Process of Clerodendrum philippinum Schauer var. simplex Mlodenke Total Flavonoids(CPTF) by Central Composite Design-Response Surface Methodology 被引量:3
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作者 Bo LI Simao HUANG +3 位作者 Xiaohua PANG Boting XI Houkang CAO Kefeng ZHANG 《Medicinal Plant》 CAS 2018年第3期17-20,共4页
[Objectives] The research aimed to optimize extraction process of Clerodendrum philippinum Schauer var. simplex Mlodenke total flavonoids( CPTF),and provide reference for its development and utilization. [Methods] Bas... [Objectives] The research aimed to optimize extraction process of Clerodendrum philippinum Schauer var. simplex Mlodenke total flavonoids( CPTF),and provide reference for its development and utilization. [Methods] Based on single-factor test,ethanol concentration,extraction temperature and extraction time were taken as independent variables,and total flavonoids yield was taken as dependent variable. The test was conducted according to central composite design principle. Multivariate linear regression and binomial equation fitting of the result were conducted,and extraction process of CPTF was optimized by using response surface methodology. [Results]The optimal extraction process of CPTF was as below: ethanol concentration 54. 76%,extraction temperature 83. 92℃,extraction time 102. 64 min,solid-liquid ratio 1:20,extraction for twice. [Conclusions] The extraction process of CPTF by central composite design-response surface methodology was simple and feasible,with reliable prediction result,which was suitable for industrial production. 展开更多
关键词 Central composite design-response surface methodology Guoqiangfeng total flavonoids Extraction process
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A Polynomial Time Algorithm for Checking Regularity of Totally Normed Process Algebra
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作者 杨非 黄浩 《Journal of Shanghai Jiaotong university(Science)》 EI 2015年第3期273-280,共8页
A polynomial algorithm for the regularity problem of weak and branching bisimilarity on totally normed process algebra(PA) processes is given. Its time complexity is O(n3+ mn), where n is the number of transition rule... A polynomial algorithm for the regularity problem of weak and branching bisimilarity on totally normed process algebra(PA) processes is given. Its time complexity is O(n3+ mn), where n is the number of transition rules and m is the maximal length of the rules. The algorithm works for totally normed basic process algebra(BPA) as well as basic parallel process(BPP). 展开更多
关键词 regularity checking totally normed process algebra(PA) weak bisimulation
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Optimization of Extraction Process of Total Flavonoids from Akebia trifoliata (Thunb.) Koidz. by Central Composite Design-Response Surface Methodology 被引量:4
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作者 Houkang CAO Boting XI +2 位作者 Simao HUANG Xiaohua PANG Kefeng ZHANG 《Medicinal Plant》 2017年第2期15-18,共4页
[Objectives]To optimize extraction process of total flavonoids from Akebia trifoliata( Thunb.) Koidz.,so as to provide references for development and use of Akebia trifoliata( Thunb.) Koidz. [Methods]The extraction ra... [Objectives]To optimize extraction process of total flavonoids from Akebia trifoliata( Thunb.) Koidz.,so as to provide references for development and use of Akebia trifoliata( Thunb.) Koidz. [Methods]The extraction rate of total flavonoids of Akebia trifoliata( Thunb.)Koidz. was taken as observation indicator. On the basis of single factor experiment,central composite design( CCD) was used to evaluate the effects of the extraction temperature,extraction time,and ethanol concentration on the extraction process. Multiple linear regression and binomial fitting were used,and response surface methodology( RSM) was used to select the optimum extraction process. [Results] The optimum extraction process conditions for total flavonoids of Akebia trifoliata( Thunb.) Koidz. was extraction temperature: 83. 92 ℃; extraction time:96. 47 min; ethanol concentration: 63. 92%; extraction times: two times; solid to liquid ratio: 1 ∶ 20; extraction rate of total flavonoids:4. 55%. [Conclusions] The central composite design-response surface methodology( CCD-RSM) is simple,convenient,and feasible for extraction of total flavonoids from Akebia trifoliata( Thunb.) Koidz.,and the prediction results are reliable. 展开更多
关键词 CENTRAL composite design-response surface methodology(CCD-RSM) Akebia trifoliata(Thunb.) Koidz. total FLAVONOIDS Extraction process
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Optimization of Extraction Process and Content Determination of Total Flavonoids from Sanguisorbae Radix and Carbonized Sanguisorba Root by Orthogonal Experimental Design 被引量:1
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作者 Fenglin WANG Yunzhang XU +1 位作者 Jingxia WANG Yuan LIU 《Medicinal Plant》 2017年第6期5-9,共5页
[Objectives] To optimize the extraction process of total flavonoids from Sanguisorbae Radix and carbonized Sanguisorba root,compare quality of different batches of Sanguisorbae Radix,study the effects of processing on... [Objectives] To optimize the extraction process of total flavonoids from Sanguisorbae Radix and carbonized Sanguisorba root,compare quality of different batches of Sanguisorbae Radix,study the effects of processing on the content of flavonoids,and provide scientific basis for reasonable utilization of Sanguisorbae Radix. [Methods] Test samples were prepared by heating,refluxing,and extraction,the extraction process was optimized by orthogonal experiment design,color was developed by NaNO_2-Al( NO_3)3-NaOH,and total flavonoids were measured by UV method at the wavelength of 510 nm. [Results] The linear relationship of rutin was excellent in the concentration range of 0. 1248 mg/mL-0. 5712 mg/mL,R^2= 0. 9997; the average recovery was 99. 67% and the RSD was 0. 70%. The optimum extraction conditions were as follows: the volume fraction of ethanol was 50%,the extraction temperature was 90℃,the extraction time was 90 min,and the solid-to-liquid ratio was 1∶ 20( g/mL). [Conclusions] After optimization of the extraction process,the extraction rate of total flavonoids in samples of Sanguisorbae Radix was significantly increased; there was certain difference in the content of total flavonoids between different batches of Sanguisorbae Radix and processed products; the total flavonoids significantly declines in carbonized sanguisorba root,and the influence of processing on its curative effect was to be further studied. 展开更多
关键词 Sanguisorbae RADIX Carbonized sanguisorba ROOT total FLAVONOIDS EXTRACTION process CONTENT determination
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Effect of Different Processing Techniques on the Content of Total Alkaloids in Toddalia asiatica Lam.
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作者 Long CHEN Miao ZHANG +2 位作者 Daogen LAO Jiaying TANG Qiuyan HUANG 《Agricultural Biotechnology》 CAS 2019年第4期165-168,共4页
[Objectives]Effects of different processing techniques on the total alkaloid content in Toddalia asiatica Lam.were investigated by ultraviolet spectrophotometry.[Methods]T.asiatica was processed by the water washing m... [Objectives]Effects of different processing techniques on the total alkaloid content in Toddalia asiatica Lam.were investigated by ultraviolet spectrophotometry.[Methods]T.asiatica was processed by the water washing method,water boiling method,water steaming method,wine steaming method and wine processing method,and the total alkaloid content was determined by ultraviolet spectrophotometry.[Results]Different processing methods can affect the total alkaloid content in the medicinal materials.Among them,the water steaming method and the wine processing method can increase the total alkaloid content of the medicinal materials,and the degree of improvement was higher in the water steaming method;and the water boiling method,water washing method and wine steaming method can reduce the total alkaloid content of the materials,and showed a reduction order of water boiling method>water washing method>wine steaming method.[Conclusions]The water steaming method and the wine processing method can increase the total alkaloid content in T.asiatica,and the water boiling method,water washing method and wine steaming method can reduce the total alkaloid content of the medicinal material. 展开更多
关键词 Toddalia asiatica Lam. processING technique total ALKALOIDS ULTRAVIOLET SPECTROPHOTOMETRY
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Theoretical investigation of total-asymmetric simple exclusion processes with attachment and detachment
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作者 Xiao Song Liu Ming-Zhe +1 位作者 Shang Jing Wang Hua 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期218-223,共6页
In this paper, traffic systems with attachment and detachment have been studied by total-asymmetric simple exclusion processes (TASEPs). Attachment and detachment in a one-dimensional system is a type of complex geo... In this paper, traffic systems with attachment and detachment have been studied by total-asymmetric simple exclusion processes (TASEPs). Attachment and detachment in a one-dimensional system is a type of complex geometry that is relevant to biological transport with the random update rule. The analytical results are presented and have shown good agreement with the extensive Monte Carlo computer simulations. 展开更多
关键词 total-asymmetric simple exclusion process attachment and detachment mean-field approach Monte Carlo simulations
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The migration of total dissolved solids during natural freezing process in Ulansuhai Lake 被引量:13
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作者 Yan ZHANG ChangYou LI +1 位作者 XiaoHong SHI Chao LI 《Journal of Arid Land》 SCIE 2012年第1期85-94,共10页
High total dissolved solids (TDS) content is one of the most important pollution contributors in lakes in arid and semiarid areas. Ulansuhai Lake, located in Urad Qianqi, Inner Mongolia, China, was selected as the o... High total dissolved solids (TDS) content is one of the most important pollution contributors in lakes in arid and semiarid areas. Ulansuhai Lake, located in Urad Qianqi, Inner Mongolia, China, was selected as the object of study. Temperatures and TDS contents of both ice and under-ice water were collected together with corresponding ice thickness. TDS profiles were drawn to show the distribution of TDS and to describe TDS migration. The results showed that about 80% (that is 3.602x108 kg) of TDS migrated from ice to water during the whole growth period of ice. Within ice layer, TDS migration only occurred during initial ice-on period, and then perished. The TDS in ice decreased with increasing ice thickness, following a negative exponential-like trend. Within un- der-ice water, the TDS migrated from ice-water interface to the entire water column under the effect of concentra- tion gradient until the water TDS content was uniform. In winter, 6.044x 107 kg (16.78% of total TDS) TDS migrated from water to sedirnent, which indicated that winter is the best time for dredging sediment. The migration effect gives rise to TDS concentration in under-ice water and sediment that is likely to affect ecosystem and water quality of the Yellow River. The trend of transfer flux of ice-water and water-sediment interfaces is similar to that of ice growth rate, which reveals that ice growth rate is one of the determinants of TDS migration. The process and mechanism of TDS migration can be referenced by research on other lakes with similar TDS content in cold and arid areas. 展开更多
关键词 arid and semiarid areas Ulansuhai Lake total dissolved solids (TDS) migration natural freezing process transferflux ice growth rate
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Asymptotic Evaluations of the Stability Index for a Markov Control Process with the Expected Total Discounted Reward Criterion
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作者 Jaime Eduardo Martínez-Sánchez 《American Journal of Operations Research》 2021年第1期62-85,共24页
In this work, for a control consumption-investment process with the discounted reward optimization criteria, a numerical estimate of the stability index is made. Using explicit formulas for the optimal stationary poli... In this work, for a control consumption-investment process with the discounted reward optimization criteria, a numerical estimate of the stability index is made. Using explicit formulas for the optimal stationary policies and for the value functions, the stability index is explicitly calculated and through statistical techniques its asymptotic behavior is investigated (using numerical experiments) when the discount coefficient approaches 1. The results obtained define the conditions under which an approximate optimal stationary policy can be used to control the original process. 展开更多
关键词 Control Consumption-Investment process Discrete-Time Markov Control process Expected total Discounted Reward Probabilistic Metrics Stability Index Estimation
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ABSOLUTE CONTINUITIES OF EXIT MEASURES AND TOTAL WEIGHTED OCCUPATION TIME MEASURES FOR SUPER-α-STABLE PROCESSES
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作者 张静 任艳霞 《Acta Mathematica Scientia》 SCIE CSCD 2006年第2期358-370,共13页
Suppose X is a super-α-stable process in R^d, (0 〈 α〈 2), whose branching rate function is dr, and branching mechanism is of the form ψ(z) = z^1+β (0 〈0 〈β ≤1). Let Xγ and Yγ denote the exit measur... Suppose X is a super-α-stable process in R^d, (0 〈 α〈 2), whose branching rate function is dr, and branching mechanism is of the form ψ(z) = z^1+β (0 〈0 〈β ≤1). Let Xγ and Yγ denote the exit measure and the total weighted occupation time measure of X in a bounded smooth domain D, respectively. The absolute continuities of Xγ and Yγ are discussed. 展开更多
关键词 Super-α-stable process absolute continuity exit measure total weighted occupation time measure
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兰州软儿梨梨膏加工工艺优化及对其活性成分与品质的影响
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作者 张芳 易昊 +4 位作者 吾拉力森·赛力克哈孜 李明泽 周媛媛 孙霞芝 黄玉龙 《食品安全质量检测学报》 2026年第6期118-127,共10页
目的探究不同工艺处理对兰州软儿梨膏抗氧化活性和可溶性固形物的影响,以及软儿梨梨膏制备的最佳工艺条件。方法以兰州软儿梨为原料,采用先单因素后正交试验设计的方法,通过研究不同后熟期、浓缩时间、浓缩温度、加水量、D-异抗坏血酸... 目的探究不同工艺处理对兰州软儿梨膏抗氧化活性和可溶性固形物的影响,以及软儿梨梨膏制备的最佳工艺条件。方法以兰州软儿梨为原料,采用先单因素后正交试验设计的方法,通过研究不同后熟期、浓缩时间、浓缩温度、加水量、D-异抗坏血酸钠添加量对制备的梨膏中可溶性固形物、总黄酮及总酚及感官评价等指标的影响,分析上述各因素对各评价指标的影响次序,确定最优梨膏制备工艺条件。结果上述工艺因素对梨膏的总酚和总黄酮含量影响显著。通过优化确定最佳制备工艺条件为:后熟时间30 d、浓缩时间35 min、浓缩温度65℃、加水量20%、D-异抗坏血酸钠添加量0.70%。经验证,该工艺下所得梨膏的可溶性固形物含量为87%,总黄酮和总酚含量分别为682.00 mg/kg、484.67 mg/kg,表明其活性成分保留良好,抗氧化特性显著,感官品质评分平均评分81.5分。结论本研究优化得到了兰州软儿梨梨膏的最佳制备工艺,该工艺能有效保留总黄酮、总酚等活性成分,显著提升产品可溶性固形物含量与感官品质,为兰州软儿梨梨膏的标准化生产提供了可靠的理论依据与工艺参考。 展开更多
关键词 兰州软儿梨 梨膏 工艺优化 总酚 总黄酮 可溶性固形物 感官品质
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千里光总黄酮响应面法提取优化与抗氧化活性研究
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作者 罗春燕 林锦霞 +4 位作者 许钧西 林淑贞 陈艳锦 张宽 林诗莹 《中医药导报》 2026年第3期44-50,共7页
目的:研究千里光总黄酮提取工艺的优化,并测定其抗氧化性。方法:基于单因素试验结合响应面法优化千里光总黄酮的提取工艺,并评估其体外抗氧化能力。结果:溶剂体系选用52%乙醇溶液,料液比控制在1∶47(g/mL),提取温度在79℃条件下进行41 ... 目的:研究千里光总黄酮提取工艺的优化,并测定其抗氧化性。方法:基于单因素试验结合响应面法优化千里光总黄酮的提取工艺,并评估其体外抗氧化能力。结果:溶剂体系选用52%乙醇溶液,料液比控制在1∶47(g/mL),提取温度在79℃条件下进行41 min水浴提取。经验证实验测得总黄酮提取达53.27 mg/g(以原料干质量计),该工艺参数显著提高了黄酮类物质的溶出效率。抗氧化试验中千里光总黄酮在DPPH和ABTS自由基清除中IC_(50)分别为0.40 mg/mL和3.76 mg/mL。结论:响应面法优化千里光总黄酮提取工艺方案设计稳定可行,且千里光具有良好的抗氧化能力。 展开更多
关键词 千里光 总黄酮 响应面法 抗氧化 工艺优化
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黄芩趁鲜切制饮片的指纹图谱建立与抗氧化活性成分的化学模式识别
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作者 李莎莎 毛阿娟 +4 位作者 黄杰 李芳 李凡 张红 王卫锋 《时珍国医国药》 北大核心 2026年第6期1062-1068,共7页
目的 评价黄芩趁鲜切制饮片体外抗氧化活性,并建立其指纹图谱,通过化学模式识别进行分析。方法 采用1,1-二苯基-2-三硝基苯肼(DPPH)自由基及2,2’-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS)自由基清除实验考察黄芩趁鲜切制饮片的抗... 目的 评价黄芩趁鲜切制饮片体外抗氧化活性,并建立其指纹图谱,通过化学模式识别进行分析。方法 采用1,1-二苯基-2-三硝基苯肼(DPPH)自由基及2,2’-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS)自由基清除实验考察黄芩趁鲜切制饮片的抗氧化活性;采用高效液相色谱(HPLC)法,以黄芩苷为参照峰,采用《中药色谱指纹图谱相似度评价系统(2012版)》对24批黄芩趁鲜切制饮片绘制指纹图谱并进行相似度评价,确定共有特征峰;采用SPSS 26.0软件进行Spearman相关性分析,筛选可能具有体外抗氧化活性的潜在化合物,结合灰色关联度分析和偏最小二乘法回归分析探讨成分与活性之间关系。结果 DPPH自由基清除实验的半数抑制浓度(IC_(50))为0.127~0.672 mg·mL^(-1),ABTS自由基清除实验的IC_(50)为9.758~18.740μg·mL^(-1)。24批黄芩趁鲜切制饮片共有20个共有峰,相似度达到0.999~1.000;共指认其中4个共有峰,分别为峰6(黄芩苷)、峰12(汉黄芩苷)、峰15(黄芩素)、峰17(汉黄芩素)。灰色关联度分析和偏最小二乘法回归分析表明,峰7、峰12(汉黄芩苷)、峰3、峰6(黄芩苷)、峰15(黄芩素)、峰4、峰5、峰8、峰10、峰9和峰17(汉黄芩素)是黄芩趁鲜切制饮片抗氧化活性的主要特征峰。结论 所建立的指纹图谱能够有效评价黄芩趁鲜切制饮片的质量;黄芩趁鲜切制饮片的抗氧化活性是由多成分协同作用的结果,揭示了其抗氧化活性的潜在药效物质基础。 展开更多
关键词 黄芩 趁鲜切制 总黄酮 抗氧化 指纹图谱
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富集生物活性成分发芽糙米的制备工艺优化
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作者 贾春艳 李祥 +4 位作者 武陈晨 丁春阳 郑秋鹛 张娜 刘晓飞 《哈尔滨商业大学学报(自然科学版)》 2026年第2期223-232,239,共11页
为拓宽糙米在全谷物食品领域的应用,采用单因素实验联用Box-Behnken优化富含生物活性成分发芽糙米的制备工艺,以发芽糙米中γ-氨基丁酸、总酚质量比为响应值,对富集生物活性成分的发芽糙米制备工艺进行研究,探究浸泡温度、浸泡时间、氯... 为拓宽糙米在全谷物食品领域的应用,采用单因素实验联用Box-Behnken优化富含生物活性成分发芽糙米的制备工艺,以发芽糙米中γ-氨基丁酸、总酚质量比为响应值,对富集生物活性成分的发芽糙米制备工艺进行研究,探究浸泡温度、浸泡时间、氯化钙溶液浓度、发芽温度、发芽时间对发芽糙米中生物活性成分含量的影响.结果表明最佳制备工艺为:浸泡温度35℃、浸泡时间8 h、氯化钙溶液浓度3 mmol/L、发芽温度30℃,发芽时间25 h,γ-氨基丁酸、总酚质量比较高,分别为1.84 mg/g和3.13 mg/g,与未发芽糙米相比,分别增加4.59、8.74倍.经过发芽处理后,糙米中还原糖含量增加8.95倍,膳食纤维、γ-谷维素和谷胱甘肽含量有所增加,蛋白质、淀粉、脂肪和植酸含量有所减少. 展开更多
关键词 发芽糙米 Γ-氨基丁酸 总酚 工艺优化 营养成分 活性物质
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牛蒡根总多酚提取工艺以及含量测定
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作者 张雅婷 郑彧 +1 位作者 孙翌勋 曲扬 《药学研究》 2026年第3期275-280,共6页
目的优化牛蒡根总多酚的提取工艺,建立纯化富集方法并测定其特征指标成分含量,为后续研究提供基础。方法以总多酚含量为评价指标,通过单因素试验筛选乙醇体积分数、料液比、提取温度的最佳参数;经石油醚脱脂、正丁醇萃取及AB-8型大孔吸... 目的优化牛蒡根总多酚的提取工艺,建立纯化富集方法并测定其特征指标成分含量,为后续研究提供基础。方法以总多酚含量为评价指标,通过单因素试验筛选乙醇体积分数、料液比、提取温度的最佳参数;经石油醚脱脂、正丁醇萃取及AB-8型大孔吸附树脂富集纯化提取物;采用福林-酚法测定总多酚含量,高效液相色谱(HPLC)法定量7种指标性多酚成分。结果最佳提取工艺为70%乙醇、料液比1:15(g:mL)、60℃提取,粗提物总多酚含量2.71%;经纯化富集后,总多酚含量提升至59.84%。HPLC测定显示,新绿原酸、绿原酸等7种指标成分总占比达提取物的28.05%。结论本研究确定的提取与富集工艺高效可行,明确了提取物的主要成分含量,为牛蒡根多酚的开发利用提供了技术支撑。 展开更多
关键词 牛蒡根 总多酚 工艺优化 大孔树脂富集 高效液相色谱法
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银杏叶总黄酮提取工艺优化及抗氧化活性研究
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作者 陈亮互 刘珈梦 +7 位作者 陈惊鸿 刘文杰 贾美卉 释恒顺 胡合殊 卢轩 冯宝民 肖栋梁 《广州化工》 2026年第4期74-78,共5页
本研究旨在优化银杏叶中总黄酮的提取工艺,并评价其体外抗氧化活性。以总黄酮提取量为主要评价指标,首先通过单因素试验考察提取时间、乙醇浓度、料液比及提取次数对提取效果的影响,结果表明上述因素均对总黄酮提取量具有显著影响。在... 本研究旨在优化银杏叶中总黄酮的提取工艺,并评价其体外抗氧化活性。以总黄酮提取量为主要评价指标,首先通过单因素试验考察提取时间、乙醇浓度、料液比及提取次数对提取效果的影响,结果表明上述因素均对总黄酮提取量具有显著影响。在此基础上,采用正交试验对提取工艺进行优化,确定最佳提取条件为:超声温度40℃,超声提取时间2.0 h,乙醇浓度70%,料液比1∶25,提取次数4次。进一步通过ABTS自由基清除实验,测定银杏叶茶总黄酮的体外抗氧化活性,结果显示其具有良好的自由基清除能力,表明银杏叶总黄酮具有较强的抗氧化潜力。该研究为银杏叶资源的高效利用及其功能产品的开发提供了理论依据和实验参考。 展开更多
关键词 银杏叶茶 总黄酮 提取工艺优化 抗氧化活性
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VD调铝工艺对钢中夹杂物影响的机理研究
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作者 杨赵军 刘敏 +3 位作者 任英 李继新 胡显堂 李阳 《炼钢》 北大核心 2026年第2期25-30,38,共7页
通过对比传统VD高铝工艺(高铝钢水进站)与VD调铝工艺(低铝钢水进站、破空后调铝)对Q355风电钢的钢水洁净度影响,发现VD调铝工艺显著改善钢水质量并降低铝成本。试验表明:VD调铝工艺使钢中夹杂物数密度在VD进站阶段降幅达51.8%,夹杂物面... 通过对比传统VD高铝工艺(高铝钢水进站)与VD调铝工艺(低铝钢水进站、破空后调铝)对Q355风电钢的钢水洁净度影响,发现VD调铝工艺显著改善钢水质量并降低铝成本。试验表明:VD调铝工艺使钢中夹杂物数密度在VD进站阶段降幅达51.8%,夹杂物面积占比在浇铸阶段降幅达29.8%;同时夹杂物Al_(2)O_(3)占比大幅降低33.35%,而CaO占比上升,促使夹杂物从CA_(2)-C_(12)A_(7)向液态C_(12)A_(7)转变,钢板B类粗系夹杂物评级均值降低45%。钢中全氧质量分数在各阶段下降11.8%~24.8%,因铝含量降低脱硫效率减弱。成本方面,铝耗由3.09 kg/t降至2.67 kg/t,节省成本7.56元/t。结果表明,VD调铝工艺在提升钢水洁净度和经济性方面效果显著。 展开更多
关键词 VD调铝工艺 夹杂物 全氧含量 脱氮率 脱硫率 成本
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乌头茎叶总生物碱提取纯化工艺研究
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作者 乔继续 李春蓉 +3 位作者 初天哲 季宁平 谭玉柱 陈胡兰 《中药与临床》 2026年第1期7-12,共6页
目的:优化乌头茎叶中总生物碱的提取与纯化工艺条件。方法:以总生物碱提取率为评价指标,采用单因素实验考察盐酸浓度、料液比、提取温度、提取时间和提取次数对乌头茎叶总生物碱的影响,并根据单因素结果,采用L_(9)(3^(4))正交试验法优... 目的:优化乌头茎叶中总生物碱的提取与纯化工艺条件。方法:以总生物碱提取率为评价指标,采用单因素实验考察盐酸浓度、料液比、提取温度、提取时间和提取次数对乌头茎叶总生物碱的影响,并根据单因素结果,采用L_(9)(3^(4))正交试验法优选出乌头茎叶总生物碱的最佳提取工艺。通过阳离子交换树脂,分别以生物碱的吸附率和解吸率为指标,富集纯化总生物碱,优选最佳纯化工艺。结果:最佳提取工艺为盐酸浓度0.1 mol·L^(-1)、料液比1∶20、提取温度70℃、提取时间3 h、提取2次,乌头茎叶总生物碱的平均提取率为0.78%;最佳纯化工艺为选取001×12型阳离子交换树脂,上样液浓度为每l mL含原药材0.3 g、pH值=3,上样量0.5柱体积(BV),3 BV超纯水除杂,然后用4 BV的3 mol·L^(-1)氨水-95%乙醇洗脱。结论:本实验优选出的提取纯化工艺稳定可靠,为后续乌头茎叶研究开发奠定基础。 展开更多
关键词 乌头茎叶 提取纯化工艺 总生物碱 正交试验 阳离子树脂
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