Study of Total Process Energy Integration

1 INTRODUCTIONIt is known that a process system,typically a chemical process system,is composed of subsystemsof reaction,separation,heat recovery and utility with strong interactions among them.In thepast,in order to reduce the complexity of the problem,the decomposition strategy was oftenused in process energy analysis and optimization design.According to the decomposition strategy,analysis and optimization of a system are performed heuristically in several steps which

Existence of spontaneous symmetry breaking in two-lane totally asymmetric simple exclusion processes with an intersection

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.

Extraction Process and Content Determination of Total Flavonoids in Ginkgo( Ginkgo biloba L. ) Leaves

[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.

Optimization of Extraction Process of Clerodendrum philippinum Schauer var. simplex Mlodenke Total Flavonoids(CPTF) by Central Composite Design-Response Surface Methodology

[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.

Optimization of Extraction Process of Total Flavonoids from Akebia trifoliata (Thunb.) Koidz. by Central Composite Design-Response Surface Methodology

[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.

Optimization of Extraction Process and Content Determination of Total Flavonoids from Sanguisorbae Radix and Carbonized Sanguisorba Root by Orthogonal Experimental Design

[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.

Effect of Different Processing Techniques on the Content of Total Alkaloids in Toddalia asiatica Lam.

[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.

Theoretical investigation of total-asymmetric simple exclusion processes with attachment and detachment

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.

The migration of total dissolved solids during natural freezing process in Ulansuhai Lake

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.

Separation and Purification Process of Total Flavones from Litchi Pericarp by Macroporous Absorption Resin

[Objective] This study aimed to optimize the conditions for purification of total flavones from litchi pericarp by macroporous absorption resin.[Method] The flavones adsorption rates and desorption rates of macroporous absorption resins(AB-8,HPD-600,D101) were compared,and the technological parameters of D101 during the purification process were investigated.[Result] D101 macroporous absorption resin was appropriate for the purification of total flavonoids from litchi pericarp.The optimal technological conditions were selected:the pH of sample solution was 5.0;concentration of sample solution was 4 mg/ml,with a volume of 2.5BV;80% ethanol was used as elution solution,with a volume of 2.0BV.[Conclusion] The content of total flavones achieved 83% after separation by D101 macoporous absorption resin.

响应面法优化芡实露酒浸提工艺

以湿芡实和食用酒精为原料,采用浸提工艺制备露酒。在单因素试验基础上,采用响应面试验优化芡实露酒浸提工艺条件,并测定其理化指标及抗氧化活性。结果表明:最佳浸提工艺条件为食用酒精体积分数63%、芡实添加量34 g、浸提时间6 d、浸提温度25℃。在此条件下,芡实露酒总酚含量为46.4 mg/L、黄酮含量7.2 mg/L,对DPPH·和ABTS^(+)·的清除率分别为66.33%和52.08%。

Asymptotic Evaluations of the Stability Index for a Markov Control Process with the Expected Total Discounted Reward Criterion

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.

响应面法优化马齿苋总多酚提取工艺及其抗氧化活性分析

以马齿苋为原料,采用超声辅助提取马齿苋总多酚。以总多酚提取量为指标,在单因素试验的基础上通过响应面法优化提取工艺,并分析马齿苋总多酚的抗氧化活性。结果表明:最佳提取工艺为液料比30:1(mL/g)提取温度45℃、乙醇体积分数60%、提取时间40min,在此条件下马齿苋总多酚提取量为6.89mg/g。抗氧化试验表明,马齿苋总多酚具有较好的抗氧化活性。

ABSOLUTE CONTINUITIES OF EXIT MEASURES AND TOTAL WEIGHTED OCCUPATION TIME MEASURES FOR SUPER-α-STABLE PROCESSES

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.

火麻仁中水溶性活性蛋白质与糖类成分的研究进展

火麻仁为药食同源中药,应用历史久远,含有丰富的火麻油、大麻素类、木脂素酰胺类、火麻蛋白、多糖等成分,具有润肠通便的功效,在食品和医药领域都表现出较好的开发前景。笔者通过查阅近10年火麻仁的相关文献报道,对其主要水溶性活性蛋白质与糖类的最新研究进行了分析整理,发现火麻仁蛋白是一种优质的植物蛋白,主要由天冬氨酸、精氨酸、赖氨酸等氨基酸构成,具有通便、抗疲劳、抗衰老、抗氧化等药理作用,可通过碱提(酸沉)法、盐析法、酶解法等方法提取纯化,毒理学研究证实其应用较为安全;火麻仁中水溶性总糖含量约为3%~6%,主要具有免疫调节及抗氧化作用,可通过微波辅助提取进行制备,但相关单糖组成、糖链连接等结构研究还未深入开展。

响应面法对金银花叶总黄酮与绿原酸同步萃取工艺的优化

采用响应面法,对加压辅助溶剂同步萃取金银花叶总黄酮和绿原酸的工艺进行了优化。在单因素试验的基础上,综合评价总黄酮和绿原酸的得率“OD值”作为因变量,通过响应面法优化了液料比、萃取压力、溶剂体积分数、萃取温度和萃取时间。结果表明,优化后的加压辅助溶剂同步萃取工艺参数为:液料比26.5 mL/g,萃取压力3.1 MPa,溶剂体积分数60.5%,萃取温度90.3℃,萃取时间32 min。该工艺条件下,从金银花叶中萃取总黄酮得率为205.3 mg/g,绿原酸得率为24.5 mg/g, OD值与理论预测值的相对误差为1.0%。

人参不定根总皂苷的提取工艺优化及其抗氧化与抗疲劳作用

目的:探究人参不定根总皂苷(ginseng adventitious roots total saponins,GARS)的最佳提取工艺及抗氧化和抗疲劳作用。方法:利用乙醇回流法提取GARS,通过正交试验考察乙醇浓度、料液比、提取温度、提取时间对GARS含量的影响;以1,1-二苯基-2-三硝基苯肼(DPPH)、2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS+)、3-氧代-2-苯基-4,4,5,5-四甲基咪唑啉-1-氧(PTIO)、羟自由基(·OH)、超氧阴离子自由基(O_(2)^(-)·)清除能力及还原力作为测定抗氧化活性指标;通过测定小鼠力竭游泳和爬杆时间,测定肌/肝糖原、乳酸(LD)、尿素氮(BUN)含量及乳酸脱氢酶(LDH)活性来判定GARS抗疲劳能力。结果:通过正交试验得到最佳提取工艺条件为乙醇浓度70%、料液比1:30 g/mL、提取温度70℃、提取时间40 min,得到GARS含量为107.85 mg/g;GARS对DPPH、ABTS^(+)、PTIO、OH、O_(2)^(-)自由基都有一定程度清除作用,且具有还原性,其清除能力和还原性与浓度呈正比;GARS能够显著延长小鼠力竭游泳和爬杆时间(P<0.05),显著增加肌/肝糖原含量(P<0.05),降低LD、BUN含量,提高LDH活性,并与其浓度呈正比。结论:GARS提取的最优条件为乙醇浓度70%、料液比1:30 g/mL、提取温度70℃、提取时间40 min,可为GARS产业化生产提供依据,且GARS具有一定的抗氧化和抗疲劳作用,可为明确人参不定根营养成分和活性物质提供理论支持,为开发人参不定根药食同源的相关产品提供技术参考。

大亳菊总黄酮的提取及其颗粒剂制备工艺研究

优选大亳菊总黄酮的提取及其颗粒剂制备工艺。采用正交试验,以总黄酮提取率为判断标准,优选大亳菊总黄酮的提取工艺;以成型率为判断标准,优选大亳菊总黄酮颗粒剂的制备工艺。结果表明,优选的大亳菊总黄酮提取工艺为:液料比为25∶1,乙醇体积分数75%,提取温度85℃,回流时间1.25h;优选的制粒工艺为:可溶性淀粉∶糊精=1∶1,浸膏粉∶辅料=1∶3,干燥温度60℃,干燥时间2h。该工艺简便、稳定,可以用于大亳菊总黄酮的提取及其颗粒剂的制备。

金银花总黄酮低共熔溶剂提取工艺优化

目的优化金银花总黄酮低共熔溶剂提取工艺。方法在单因素试验基础上,以1,3-丁二醇与氯化胆碱比例、液料比、超声时间为影响因素,总黄酮得率为评价指标,响应面法和BP神经网络优化提取工艺。结果BP神经网络优化总黄酮得率高于响应面法优化。最优条件为1,3-丁二醇与氯化胆碱比例2.7∶1,液料比27∶1,超声时间29 min,总黄酮得率为7.85%。结论该方法稳定可靠,可用于低共熔溶剂提取金银花总黄酮。

基于TLS的改进子空间投影算法

针对经典MUSIC算法在信源相干、低信噪比、小快拍数等非理想环境下性能失效的问题,提出了一种改进的基于TLS的加权子空间投影算法。首先对阵列接收的数据协方差矩阵进行重构处理,以达到解相干目的;其次充分利用子空间信息,基于总体最小二乘拟合方法对特征值进行拟合修正,基于修正MUSIC算法思想,利用校正后的噪声特征值和信号特征值分别对噪声子空间和信号子空间进行加权处理,得到改进后的噪声子空间和信号子空间,并将两者结合得到新的空间谱函数;最后进行谱峰搜索,完成信号源的波达方向估计。仿真结果表明,改进后的算法既适用于相干信号环境,在低信噪比、小快拍数及信号入射角度间隔较小的情况下,又能有效估计出信源的波达方向。