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贮存过程中酒花新鲜度的判别 被引量:4
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作者 孙军勇 李崎 顾国贤 《酿酒》 CAS 北大核心 2001年第6期51-52,共2页
对 6种贮存了不同时间的酒花进行测定 ,研究酒花贮存指数 (H .S .I值 )
关键词 酒花 酒花 定存指数 劣化度 啤酒 新鲜度 评价
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Extraction Storage and Qualitative Analysis of Free Radicals Scavenging Substances from Sweet Potato Leaves 被引量:9
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作者 王友升 董银卯 +1 位作者 宋彦 黑维俭 《Agricultural Science & Technology》 CAS 2008年第2期1-5,9,共6页
[ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging sub... [ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging substances from sweet potato leaves were optimized by orthogonal test and the bioactive components in extracts were investigated by correlation analysis. [ Result] Sweet potato leaves contain the bioactive substances scavenging DPPH free radical and hydroxyl free radical. Extracting solvent species is the most important factor that influencing extraction yield. The optimal extraction and storage conditions are as following: water as solvent, pH 8.0 of extracting liquid, storage at 25 ℃. There is a good positive linear relationship between the content of total phenols in sweet potato leaves and corresponding scavenging rates against both the DPPH free radical and hydroxyl free radical. For the content of total flavones in sweet potato leaves, just a correlation with scavenging rate against hydroxyl free radical shown in test. [ Conclusion] The phenols in ex- tracts could effectively scavenge both the DPPH free radical and hydroxyl free radical, whereas the flavones in extracts can only function on the hydroxyl free radical. 展开更多
关键词 Sweet potato leaves Free radicals scavenging Total phenol Total flavones
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Study on ternary polymerization of toluene diisocyanate 被引量:1
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作者 祁争健 罗振扬 +4 位作者 李祥新 孙岳明 冯卫东 王华林 颜大志 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期265-269,共5页
For the production of reactive polyurethane cross-linkinger and curing agents, 2, 4-diisocyanate toluene (TDI) terpolymer, which possesses the rigid structures of hexatomic ring and three reactive functional groups,... For the production of reactive polyurethane cross-linkinger and curing agents, 2, 4-diisocyanate toluene (TDI) terpolymer, which possesses the rigid structures of hexatomic ring and three reactive functional groups, was synthesized and characterized by the Fourier transform infrared (FFIR), the gel permeation chromatography (GPC) and the chemical analysis methods. The reaction conditions were studied and optimized. A tracking research on the polymerization process of TDI was taken by using the GPC. The formation processes of the terpolymer, oligomers and higher-polymers were also dealt with. Results show that the TDI terpolymer can be prepared in the presence of Cat-3 catalyst and at the reaction temperature of (60 ±2)℃. The reaction time is short, its outcomes have narrow molecular weights distribution, namely molecular weights from 530 to 550, Mw/Mn =1.10, and the mass fraction of NCO is (25. 0 ± 0. 5)%. With the reaction time prolonging, however, TDI can be further higher-polymedzed to form higher-polymers. Benzoyl chloride (0. 4%, mass fraction), as the stabilizing agent, can effectively inhibit the occurrence of higher-polymerization. The obtained TDI terpolymer can be stable for more than half a year. 展开更多
关键词 2 4-diisocyanate toluene TERPOLYMER gel permeation chromatography curing agent storage stability
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Analysis of stability and bullwhip effect in production-inventory systems 被引量:5
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作者 张冲 王海燕 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期101-106,共6页
To discuss the relationship between stability and bullwhip effect in the supply chain system,a basic model in a production-inventory control system is developed using difference equations.Z-transform techniques are ap... To discuss the relationship between stability and bullwhip effect in the supply chain system,a basic model in a production-inventory control system is developed using difference equations.Z-transform techniques are applied to investigate the production ordering and inventory dynamics.For the two operational regimes of sufficient inventory coverage and insufficient inventory coverage,the scope of decision parameters which make the system stable or instable is investigated.Under two operational regimes and the actual system,production release rates,stability/instability and bullwhip effect in the stable region and instable region are examined based on different demand functions,and then the numerical simulation results are given.The results show that reasonable choices of fractional adjustment of inventory and supply line can make the system stable and decrease bullwhip effect.It is summarized that the piecewise linearization based on the stability analysis approach is a valid approximation to the analysis of production-inventory ordering systems with nonlinearities.Some interesting results are obtained and they have important implications for improving inventory and order decisions in supply chain systems. 展开更多
关键词 production-inventory systems stability analysis bullwhip effect Z-TRANSFORM
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试论我国企业年金的计划设计与会计处理
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作者 彭洋 《湖南财经高等专科学校学报》 2006年第1期60-61,共2页
企业年金又称企业补充养老保险,它作为老年收入的一个补充来源,已成为养老保险体系中的一个重要支柱。文章分析了在我国发展企业年金的必要性;结合我国企业实际情况,对企业年金计划进行了具体设计;并初步探讨了对其会计处理的规范。
关键词 企业年金 定存养老金计划 会计处理
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STABILITY OF THE HIGH-ORDER BAM AND ITS PERFORMANCE ANALYSIS
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作者 陈松灿 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1997年第1期15-18,共4页
High order bidirectional associative memory (HOBAM) by Tai et al is extension to Kosko′s bidirectional associative memory(BAM). It not only possesses merits of the BAM, but also relaxes the continuity assumption for... High order bidirectional associative memory (HOBAM) by Tai et al is extension to Kosko′s bidirectional associative memory(BAM). It not only possesses merits of the BAM, but also relaxes the continuity assumption for reliable recalls and significantly improves the storage capacity and error correcting capability of the BAM. However, Tai′s performance analysis for the HOBAM is only limited in the computer simulations, in the other words, they did not give a theoretical analysis result. This paper fills the blank and gives a theoretical proof for HOBAM′s stability and storage capacity analysis so that the system can theoretically ensure all the training pattern pairs to become its stable points. 展开更多
关键词 neural networks associative memories STABILITY storage capacity
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定投及其他投资策略的收益与风险比较研究——基于世界主要股指的模拟
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作者 沈立 陈一昕 易超 《中国物价》 2022年第8期96-98,113,共4页
本文使用1995年到2021年中国、美国以及日本主要股票市场指数,模拟定投和其他投资策略,考察并对比各个策略的收益和风险。研究发现:(1)当风险收益平均超过无风险收益时,一次性投资(Lump-sum)能战胜成本平均投资(Dollar-cost averaging)... 本文使用1995年到2021年中国、美国以及日本主要股票市场指数,模拟定投和其他投资策略,考察并对比各个策略的收益和风险。研究发现:(1)当风险收益平均超过无风险收益时,一次性投资(Lump-sum)能战胜成本平均投资(Dollar-cost averaging),而定期投资(Periodic investment)能战胜定存(Periodic saving);(2)在控制波动和降低回撤方面,成本平均投资以绝对优势超过一次性投资。因此,定投在控制成本、降低风险和维持收益方面是一种理想的投资策略。 展开更多
关键词 定投 一次性投资 成本平均 定存
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Existence of Positive Solutions for Nonlinear Conjugate Boundary Value Problems
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作者 菅典兵 董正华 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期87-93,共7页
The present paper is concerned with the existence of positive solutions of the (k,n-k) conjugate boundary value problems(-1) n-k u (h) (t)=λa(t)f(u(t)),t∈(0,1), u (i) (0)=0,0≤i≤k-1, u (j) (0)=0,0... The present paper is concerned with the existence of positive solutions of the (k,n-k) conjugate boundary value problems(-1) n-k u (h) (t)=λa(t)f(u(t)),t∈(0,1), u (i) (0)=0,0≤i≤k-1, u (j) (0)=0,0≤j≤n-k-1,where λ is a positive parmeter. Krasnoselsii’s fixed point theorem is employed to obtain the existence criteria for positive solution. 展开更多
关键词 existence theorem positive solutions conjugate boundary value problem
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Studies on Ultra-dry Storage and Genetic Stability of Vegetable Seeds 被引量:2
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作者 孟淑春 李秀清 +2 位作者 马连平 卢艳 刘玲 《Agricultural Science & Technology》 CAS 2011年第12期1853-1856,共4页
[Objective] To study the long-term ultra-dry storage method and genetic stability of vegetable seeds.[Method] Seeds of Lycopersicum esculentum,Raphanus satuvus and Apium graveolen.were chosen as material.The changes o... [Objective] To study the long-term ultra-dry storage method and genetic stability of vegetable seeds.[Method] Seeds of Lycopersicum esculentum,Raphanus satuvus and Apium graveolen.were chosen as material.The changes of seed vigor,viability and genetic stability after ultra-storage were discussed by studying the seed potentiality,shoot length,germination percentage and the chromosome aberration rate of root tip cells.[Results] Maintaining the low moisture content,different vegetable species had different storage effects of the long-term storage seeds under normal temperature.The Lycopersicum esculentum and Raphanus satuvus seeds were more suitable to ultra-dry storage at normal temperature,and could keep good genetic stability,while the seeds of Apium graveolen had bad performance.[Conclusion] This study established the foundation of studying ultra-dry storage of vegetable seeds. 展开更多
关键词 SEEDS Ultra-dry storage Chromosome aberration Genetic stability
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Storage stability of SBS modified bitumen based on mixed-level orthogonal array design
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作者 杨群 何文华 《Journal of Southeast University(English Edition)》 EI CAS 2012年第3期337-343,共7页
The styrene-butadiene-styrene(SBS) modified bitumens with different contents of SBS modifiers are stored in different conditions to study the storage stability of SBS modified bitumen.Mixed-level orthogonal array de... The styrene-butadiene-styrene(SBS) modified bitumens with different contents of SBS modifiers are stored in different conditions to study the storage stability of SBS modified bitumen.Mixed-level orthogonal array design(OAD) is used and factors such as SBS modifier content,storage time,storage temperature and container size are chosen in a mixed-level OAD with an OA16(31×44) matrix.Parameters like the separation softening point difference(the separation difference of the ring and ball softening point of the top and bottom samples) and the average softening point(the arithmetic mean of the softening points of the top and bottom samples) are proposed to evaluate the separation and the ageing of modified bitumen during storage in this experiment,respectively.The results reveal that the separation and the ageing during storage exhibit a complicated variation for storage temperature and time.The separation softening point difference decreases with the storage temperature rising from 20 to 120 ℃ and increases with the temperature exceeding 120 ℃,and the average softening point drops with the storage time being prolonged.Different storage conditions have various effects on the storage stability of SBS modified bitumen. 展开更多
关键词 storage stability mixed-level orthogonal array design separation softening point difference average softening point
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Implementing VMI service pricing strategy for 3PL corporation considering recovery costs
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作者 赵林度 唐磊 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期1-7,共7页
The collector managed inventory(CMI)management idea is introduced based on the comparison of manufacturer and third-party logistics(3PL)implementing vendor managed inventory(VMI)services.Considering recovery costs,the... The collector managed inventory(CMI)management idea is introduced based on the comparison of manufacturer and third-party logistics(3PL)implementing vendor managed inventory(VMI)services.Considering recovery costs,the service pricing strategies for 3PL corporations implementing VMI are studied to meet two conditions of participation constraints and incentive-compatibility constraints.The numerical simulation results indicate that the supply chain partners' profits change after considering recovery costs,and the 3PL corporation's profits and the total profits increase first,and then decrease.The retailers' and manufacturers' profits also increase.The total profits of the supply chain have a characteristic of increasing first and then decreasing with the increase of the callback ratio of unsold products.The concrete extremum point is codetermined by price flexibility,service pricing of the 3PL corporation,callback price and callback ratio. 展开更多
关键词 recovery costs vendor managed inventory Stackelberg game service pricing
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The Stability of Endomorphin-1 Solution
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作者 刘晖 杨顶建 +1 位作者 倪京满 王锐 《Journal of Chinese Pharmaceutical Sciences》 CAS 2003年第3期131-134,共4页
Aim To study the most stable pH value of endomorphin-1 solution and toestimate the shelf-life of EM-1 solution. Methods The content of EM-1 in its solution was determinedby HPLC, and stability was studied by accelerat... Aim To study the most stable pH value of endomorphin-1 solution and toestimate the shelf-life of EM-1 solution. Methods The content of EM-1 in its solution was determinedby HPLC, and stability was studied by accelerated tests. Results The most stable pH value of EM-1solution was observed. By the accelerated tests we obtained the Arrhe-nius relationship and thepharmacokinetic parameters. Conclusion The most stable pH value of EM-1 solution is 4.5 -4.8. Thet_(1/2)(25℃) is 45 d. 展开更多
关键词 ENDOMORPHIN-1 most stable pH value accelerated tests HPLC
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Positive Periodic Solutions for Nonautonomous Differential Equations with Delay 被引量:2
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作者 PENG Shi-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第4期561-566,共6页
By utilizing a fixed point theorem on cone, some new results on the existence ofpositive periodic solutions for nonautonomous differential equations with delay are derived.
关键词 positive periodic solutions NONAUTONOMOUS differential equations with delay fixed point theorem CONE
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Quantitative analysis of Boehm' s GC 被引量:2
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作者 GUAN Xue-tao ZHANG Yuan-rui +1 位作者 GOU Xiao-gang CHENG Xu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期259-264,共6页
The term garbage collection describes the automated process of finding previously allocated memorythatis no longer in use in order to make the memory available to satisfy subsequent allocation requests. Wehave reviewe... The term garbage collection describes the automated process of finding previously allocated memorythatis no longer in use in order to make the memory available to satisfy subsequent allocation requests. Wehave reviewed existing papers and implementations of GC, and especially analyzed Boehm' s C codes, which isa real-time mark-sweep GC running under Linux and ANSI C standard. In this paper, we will quantitatively an-alyze the performance of different configurations of Boehm' s collector subjected to different workloads. Reportedmeasurements demonstrate that a refined garbage collector is a viable alternative to traditional explicit memorymanagement techniques, even for low-level languages. It is more a trade-off for certain system than an all-or-nothing proposition. 展开更多
关键词 CONSERVATIVE garbage collection INCREMENTAL mark-sweep REAL-TIME
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Existence results for a class of parabolic evolution equations in Banach spaces
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作者 王静 薛星美 《Journal of Southeast University(English Edition)》 EI CAS 2003年第2期182-187,共6页
We discuss the existence results of the parabolic evolution equation d(x(t)+g(t,x(t)))/dt+A(t)x(t)=f(t,x(t)) in Banach spaces, where A(t) generates an evolution system and functions f,g are continuous. We get the theo... We discuss the existence results of the parabolic evolution equation d(x(t)+g(t,x(t)))/dt+A(t)x(t)=f(t,x(t)) in Banach spaces, where A(t) generates an evolution system and functions f,g are continuous. We get the theorem of existence of a mild solution, the theorem of existence and uniqueness of a mild solution and the theorem of existence and uniqueness of an S-classical (semi-classical) solution. We extend the cases when g(t)=0 or A(t)=A. 展开更多
关键词 evolution system analytic semigroup mild solution semi-classical solution classical solution
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Non-zero Solution for the Quasi-linear Elliptic Equation 被引量:2
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作者 RAO Ruo-feng HE Qing-gao 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第1期117-124,共8页
In this paper, the author has given an existence theorem for the resonant equation,-△pu=λ1|u|p-2u+f(u)+h(x),without any Landesman-Lazer conditions on h(x).
关键词 P-LAPLACIAN non-zero solution first eigenvalue saddle point theorem
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Existence of Multiple Positive Solutions for Higher-Order p-Laplacian Boundary Value Problems
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作者 贺小明 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期212-216,共5页
The existence of multiple positive solutions for a class of higher order p Laplacian boundary value problem is studied. By means of the Leggett Williams fixed point theorem in cones, existence criteria which e... The existence of multiple positive solutions for a class of higher order p Laplacian boundary value problem is studied. By means of the Leggett Williams fixed point theorem in cones, existence criteria which ensure the existence of at least three positive solutions of the boundary value problem are established. 展开更多
关键词 positive solutions cone Leggett Williams fixed point theorem p Laplacian boundary value problems
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An Existence Theorem of Solution for a Singular Third-order Two-point Boundary Value Problem 被引量:1
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作者 姚庆六 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第1期61-66,共6页
By constructing suitable Banach space, an existence theorem is established under a condition of linear growth for the third-order boundary value problem u″′(t)+f(t,u(t),u′(t))=0,0〈t〈1,u(0)=u′(0)=u′... By constructing suitable Banach space, an existence theorem is established under a condition of linear growth for the third-order boundary value problem u″′(t)+f(t,u(t),u′(t))=0,0〈t〈1,u(0)=u′(0)=u′(1)=0, where the nonlinear term contains first and second derivatives of unknown function. In this theorem the nonlinear term f(t, u, v, w) may be singular at t = 0 and t = 1. The main ingredient is Leray-Schauder nonlinear alternative. 展开更多
关键词 singular ordinary differential equation boundary value problem existence theorem nonlinear alternative
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Laboratory investigation on effects of organic montmorillonite on performance of crumb rubber modified asphalt 被引量:2
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作者 TAN Zhi-hua WANG Ji-jing SHI Zhen-ning 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第12期3888-3898,共11页
In this paper,organic montmorillonite(OMMT)was added into crumb rubber modified asphalt(CRMA)to improve its high temperature performance,anti-aging performance and storage stability.The effects of different OMMT conte... In this paper,organic montmorillonite(OMMT)was added into crumb rubber modified asphalt(CRMA)to improve its high temperature performance,anti-aging performance and storage stability.The effects of different OMMT content on properties of CRMA were studied.The rutting factor obtained by dynamic shear rheological(DSR)test was adopted to evaluate the high-temperature performance.The creep stiffness and m value determined by the bending beam rheometer(BBR)test were employed to evaluate the low-temperature performance.The softening point,ductility,rutting factor before and after rolling thin film ovens test(RTFOT)and pressure aging vessel test(PAV)were compared to characterize the aging properties.Moreover,the segregation test after being reserved for 48 h and 7 d was conducted,and the softening point and rutting factor of upper and lower layers of segregation pipe were adopted to evaluate the storage stability.The results indicated that the high-temperature performance and anti-aging performance were developed with the increasing content of OMMT,while the low-temperature performance deteriorated.The storage stability was improved with the increasing content of OMMT before the content exceeded 4%,after which the storage stability declined.Taking account of all factors,it is suggested that the optimum content of OMMT is 3%−4%. 展开更多
关键词 crumb rubber modified asphalt organic montmorillonite high-temperature performance low-temperature performance storage stability.
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Immobilization of Papain in Biosflica Matrix and Its Catalytic Property 被引量:8
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作者 ZHOU Liya WANG Cui +1 位作者 JIANG Yanjun GAO Jing 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第6期670-675,共6页
A novel method was developed for papain immobilization through a biomimetic silicification process induced by papain. By incubating papain in a silica precursor solution, the papain-silica composite formed rapidly and... A novel method was developed for papain immobilization through a biomimetic silicification process induced by papain. By incubating papain in a silica precursor solution, the papain-silica composite formed rapidly and oanain was encansulated. The encansulation efficiency and the recovery activity were 82.60% and 83.09%, re-spectively. Compared with enzymes and biomolecules immobilized in biosilica matrix in the presence of additaonal silica-precipitating species, this papaln encapsulation process, a biomimetic approach, realized high encapsulation efficiency by its autosilification activity under mild conditions (near-neutral pH and ambient temperature). Fur-thermore, the encapsulated papain exhibits enhanced thermal, pH, recycling and storage stabilities. Kinetic analysis showed that the biomimetic silica matrix did not significantly hinder the mass transport of substrate or the release of product. 展开更多
关键词 PAPAIN silica matrix ENCAPSULATION biosilicification BIOMIMETIC
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