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使用价值量的计量问题分析
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作者 谭顺 《集团经济研究》 北大核心 2004年第8期62-63,共2页
传统政治经济学认为使用价值是物品具有的能够满足人的某种需要的属性,这种属性是物品的客观自然属性,是物品本身的固有属性.正是把使用价值看作物品本身固有的一成不变的属性,传统政治经济学形成了关于使用价值量问题的基本认识:使用... 传统政治经济学认为使用价值是物品具有的能够满足人的某种需要的属性,这种属性是物品的客观自然属性,是物品本身的固有属性.正是把使用价值看作物品本身固有的一成不变的属性,传统政治经济学形成了关于使用价值量问题的基本认识:使用价值量等同于有某种有用性的物品的数量.可见,物品的数量的多少是衡量使用价值量大小的标准,换言之,使用价值量通过具有某种使用价值的物品的数量来表示.其实,这些传统认识是值得商榷的. 展开更多
关键词 政治经济学 使用价值 物品性能 物品数量 商品
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Fabrication of a Knitted Biodegradable Stents for Tracheal Regeneration 被引量:3
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作者 李毅 张佩华 冯勋伟 《Journal of Donghua University(English Edition)》 EI CAS 2004年第2期98-101,共4页
Endoluminal stents for reinforcement and regeneration of human trachea have been developed by weft-knitting method on a small-diameter circular knitting machine. The constituent materials of the stent are Polyglactin,... Endoluminal stents for reinforcement and regeneration of human trachea have been developed by weft-knitting method on a small-diameter circular knitting machine. The constituent materials of the stent are Polyglactin, Polypropylene and Chitosan with Polyglactin and Polypropylene plate-stitched fabric acting as backbone while chitosan as matrix, respectively. The fabrication procedures including knitting and coating are described in this paper. Mechanical and animal tests have been carried out to evaluate the mechanical properties of the stents. 展开更多
关键词 medical stent weft knitting biodegradable material mechanical properties
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Bioactive compounds of sea cucumbers and their therapeutic effects 被引量:10
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作者 时淑娟 冯文静 +3 位作者 胡松 梁世秀 安妮娜 毛拥军 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第3期549-558,共10页
Abstract Sea cucumbers belong to the Class Holothuroidea of marine invertebrates. They are commercially valuable and prized as a food and folk medicine in Asia. Nutritionally, sea cucumbers have an impressive profile ... Abstract Sea cucumbers belong to the Class Holothuroidea of marine invertebrates. They are commercially valuable and prized as a food and folk medicine in Asia. Nutritionally, sea cucumbers have an impressive profile of valuable nutrients such as vitamins, minerals and amino acids. A number of unique biological and pharmacological activities/properties, including anticancer, anticoagulant/antithrombotic, antimicrobial, antioxidant, antihyperlipidemic, antihyperglycemic, anti-inflammatory, antihypertension and radioprotective, have been ascribed to various compounds isolated from sea cucumbers. The therapeutic properties and medicinal benefits of sea cucumbers can be linked to the presence of a wide array ofbioactives, especially triterpene glycosides, acid mucopolysaccharide, sphingoid bases, glycolipids, fucosylated chondroitin sulfate, polysaccharides, phospholipids, cerebrosides, phosphatidylcholines, and other extracts and hydrolysates. This review highlights the valuable bioactive components as well as the multiple therapeutic properties of sea cucumbers with a view to exploring their potential uses as functional foods and a natural source of new multifunctional drugs. 展开更多
关键词 sea cucumber bioactive compounds biological activities pharmacological activities therapeutic effects
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Partial Substitution of Cocoa Butter with Processed Shea Butter in Milk Chocolate
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作者 Francis Alemawo rJacob K. Agbenorhevi Adrian K. Poku 《Journal of Food Science and Engineering》 2014年第4期212-217,共6页
Natural cocoa butter is expensive but a major ingredient used for the manufacture of chocolate. The search for alternative cheaper cocoa butter substitute with the similar physical properties, fatty acid and triglycer... Natural cocoa butter is expensive but a major ingredient used for the manufacture of chocolate. The search for alternative cheaper cocoa butter substitute with the similar physical properties, fatty acid and triglyceride content has been proposed. The objective of this study was to evaluate the potential ofcbeaper and processed (fractionated- or deodorized-) shea butter (FSB or DSB) to partly substitute 5% and 7.5% cocoa butter in chocolate production. The proximate composition, microbiological and sensory qualities, as well as estimated cost of the formulated chocolate products were determined and compared with that of the 100% cocoa butter chocolate as control. Results showed that all the shea butter substituted chocolate samples varying in percentages of incorporation had acceptable proximate composition and microbial quality according to the international standards. Also, there were no significant differences (P 〉 0.05) among all the five samples in terms of flavour, after-taste and texture except for the 7.5% FSB substituted chocolate which differed significantly (P 〈 0.05) from the other samples in terms of overall acceptability, thus 7.5% FSB was less preferred by consumers. FSB is cheaper than DSB based on the world market price quotes. Thus the current study recommends the use of FSB for chocolate confectioneries at 5% substitution rate for cocoa butter could help reduce the cost of chocolate production and increase turnovers. 展开更多
关键词 Shea butter cocoa butter chocolate production.
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The Study of Diversities of Marine Microbes in China 被引量:2
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作者 ZHANG Si ZHANG Changsheng TIAN Xinpeng WANG Fazuo LI Jie 《Bulletin of the Chinese Academy of Sciences》 2010年第4期228-234,共7页
The oceans account for 71% of the Earth’s surface and are rich in the most advantageous and characteristic resources of marine microbes. The research on diversity is the key point for exploring and exploiting marine ... The oceans account for 71% of the Earth’s surface and are rich in the most advantageous and characteristic resources of marine microbes. The research on diversity is the key point for exploring and exploiting marine microbial resources. Giving attention to species diversity and genetic diversity of marine microbes, discovering novel metabolites with multiple functions, revealing key secondary metabolic process and the main regulation mechanisms in marine microbes, and developing a new technology of biosynthesis, are the important foundation for discovering innovative drugs and developing functional products with characteristics. The present paper has reviewed the recent advances in the four research areas of marine microbial species diversity, genetic diversity, chemical diversity and metabolic diversity in China. 展开更多
关键词 marine microbes DIVERSITY SPECIES GENETIC CHEMICAL METABOLIC
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Investigation on Water Jet Treated Polyester/cotton Blended Cambric
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作者 黄故 《Journal of Donghua University(English Edition)》 EI CAS 2004年第1期104-108,共5页
Analytical examination was made to ascertain the effect of the high pressure water flow on the fabric properties.Polyester/cotton blended cambric was spurted by high pressure water flow. Fabric properties such as hand... Analytical examination was made to ascertain the effect of the high pressure water flow on the fabric properties.Polyester/cotton blended cambric was spurted by high pressure water flow. Fabric properties such as handle,thickness, tensile strength , stiffness and air permeability after the water treatment were investigated. 展开更多
关键词 Cambric High pressure water jet Fabric treatment
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Energy and Nutritional Properties of the White Mulberry (Morus alba L.)
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作者 Malgorzata Lochynska 《Journal of Agricultural Science and Technology(A)》 2015年第9期709-716,共8页
The white mulberry (Morus alba L.) had been forgotten in Europe or known only as a plant associated with breeding of mulberry silkworms (Bombyx mori L.). The initial studies have shown great potential of this plan... The white mulberry (Morus alba L.) had been forgotten in Europe or known only as a plant associated with breeding of mulberry silkworms (Bombyx mori L.). The initial studies have shown great potential of this plant in energy, food and pharmaceutical industries. The leaves and fruits contain very valuable bioactive substances, which may be used in health care. Antioxidants of plant origin include flavonoids and vitamin C (ascorbic acid), and these substances are present in high amounts in anatomical parts of white mulberry. It has also been reported on the medicinal properties of this plant and its use in preventing diseases, such as atherosclerosis, diabetes, obesity and cancer. The food industry increasingly uses the white mulberry in food to provide human organism with precious bioactive substances. Functional food, due to the presence in its composition of valuable components, is beneficial to human health. What is more, very fast growth of mulberry causes that biomass of the plant may be used as biofuel or energy plant. The aim of this paper is to present the possibility of using the white mulberry as a raw material for functional foods and as an energy plant. 展开更多
关键词 Energy plant ANTIOXIDANTS functional food diseases of civilization.
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Characterization and Drying of Green Mint
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作者 Belgacem Chandoul Bechir Dbira Ahmed Bellagi 《Journal of Chemistry and Chemical Engineering》 2014年第10期955-959,共5页
Mint is a medicinal and aromatic plant. It is very important for the pharmacopoeia, perfumes, confectionery and liquor industry. Some green mint leaves without rods are used as samples. Physical and mechanical propert... Mint is a medicinal and aromatic plant. It is very important for the pharmacopoeia, perfumes, confectionery and liquor industry. Some green mint leaves without rods are used as samples. Physical and mechanical properties of the sample such as the desorption isotherms, the density and volumetric withdrawal are determined. The kinetics of drying, where it follows the changes of the water content of the sample as a function of the drying time for the three temperatures 30, 40 and 50℃, is also presented and discussed. 展开更多
关键词 MINT ISOTHERM DESORPTION SHRINKAGE KINETICS drying.
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Evaluation of Kenyan Orange Fleshed Sweet Potato (Ipomoea batatas Lam,) Purees for Functional Food Production
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作者 Muchiri M. Njeri McCartney Anne L. 《Journal of Life Sciences》 2014年第2期128-133,共6页
Consumption of functional foods with health promoting benefits and/or disease prevention has been on the increase globally. The study aimed at evaluating the potential of utilizing Kenyan orange fleshed sweet potato ... Consumption of functional foods with health promoting benefits and/or disease prevention has been on the increase globally. The study aimed at evaluating the potential of utilizing Kenyan orange fleshed sweet potato (Ipomoea batatas Lam.) for functional food production with aesthetics benefits. Purees from three different varieties of orange fleshed sweet potato (OFSP) were analyzed for nutritional, physicochemical and microbial quality, The findings of the study show that the three purees were all microbiologically safe and of near neutral pH, but differed significantly (P 〈 0.05) in nutrient content (dry matter content, 12.76-28.23%; crude fiber, 1.37-2.90% fresh weight basis (FWB); 13-carotene, 0.94-9.27 mg/100g dry weight basis (DWB); starch, 10.20-18.30% FWB & total sugar 27.08-31.76% DWB). The purees had attractive appearance (ranging from yellow to dark orange), with varying significantly different spectrophotometer hunters color scale (P 〈 0.05), and flow ability. Conclusions from the findings show great potential of utilizing the varying properties of OFSP puree to produce enriched functional food products such as probiotic/prebiotic dairy, beverages, bakery and baby foods. 展开更多
关键词 Orange fleshed sweet potato puree functional foods sustainable nutrition.
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Investigation of Dyeing Properties of Different Fabric Species with Alkanna Orientalis Root Extract
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作者 Adem Onal Ferda Eser Seda Bayrak 《Journal of Food Science and Engineering》 2017年第4期213-220,共8页
In this study, the dyeing properties of different fabric species were investigated using root extract of yellow sormunen (Alkanna orientalis). For this purpose, the cotton and wool fabrics were dyed using the root e... In this study, the dyeing properties of different fabric species were investigated using root extract of yellow sormunen (Alkanna orientalis). For this purpose, the cotton and wool fabrics were dyed using the root extract of yellow sormunen by pre-mordanting, together-mordanting and last-mordanting methods with copper sulfate (CuSO4), iron sulfate (FeSO4) and aluminum sulfate (AiK(SO4)2) at medium pH. The same procedure was applied to cotton and wool fabrics that allowed in Artifical Urinary System (AUS) [%3 NH3 + %3 urea + %3 CAC2O4(g/v)] for 24 h. The color codes were determined with Pantone Color Quide, and K/S and L* a* b* values were detected with color measurement spectrophotometer, and also washing-, crocking-fastness levels were evaluated using gray scale. According to the evaluations, the fabrics dyed pre-treated with AUS have higher fastness values than the unpre-treated dyed fabrics with AUS. 展开更多
关键词 Yellow sormunen Alkanna orientalis MORDANT WOOL cotton fastness.
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Estimating antiwear properties of esters as potential lubricantbased oils using QSTR models with CoMFA and CoMSIA 被引量:5
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作者 Zhan WANG Tingting WANG +2 位作者 Guoyan YANG Xinlei GAO Kang DAI 《Friction》 SCIE CSCD 2018年第3期289-296,共8页
Comparative molecular field analysis and comparative molecular similarity indices analysis were employed to analyze the antiwear properties of a series of 57 esters as potential lubricant-based oils. Predictive 3D-qua... Comparative molecular field analysis and comparative molecular similarity indices analysis were employed to analyze the antiwear properties of a series of 57 esters as potential lubricant-based oils. Predictive 3D-quantitative structure tribo-ability relationship models were established using the SYBYL multifit molecular alignment rule with a training set and a test set. The optimum models were all shown to be statistically significant with cross-validated coefficients q^2 > 0.5 and conventional coefficients r^2 > 0.9, indicating that the models are sufficiently reliable for activity prediction, and may be useful in the design of novel ester-based oils. 展开更多
关键词 quantitative structure tribo-ability relationship antiwear properties lubricant-based oils
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Synthesis and application of a novel combined kinetic hydrate inhibitor 被引量:6
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作者 HU Jun WANG YanHong +3 位作者 LANG XueMei DU Juan LI QingPing FAN ShuanShi 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第12期3289-3295,共7页
In oil and gas exploration and transportation, low dosage hydrate inhibitors (LDHIs) are more favorably utilized to inhibit the formation of hydrates than thermodynamic inhibitors (THs) as a trend. However, there ... In oil and gas exploration and transportation, low dosage hydrate inhibitors (LDHIs) are more favorably utilized to inhibit the formation of hydrates than thermodynamic inhibitors (THs) as a trend. However, there are no industrial products of LDHIs available domestically, and the corresponding application experience is in urgent need. In this paper, a combined hydrate inhibitor (HY-1) was synthesized after a series of reaction condition optimization, and its performance on THF hydrate inhibition was investigated using kinetic hydrate inhibitor evaluation apparatus with 6 cells bathing in air. The results show that when the reaction temperature is 60℃, the reaction time is 6 h, and the monomer: solvent ratio is 1:2, the product has the best kinetic hydrate inhibitor performance on THF hydrate. On these bases, the scale-up production of this combined hydrate inhibitor was carried out. Although the scale-up product (HY-10) performs less effectively on the THF hydrate inhibition than HY-1, it functions better than a commercial product (Inhibex501) during in-house tests. HY-10 was successfully applied to the gas production process. Field trials in northem Shaanxi PetroChina Changqing Oilfield Company (PCOC) show that 2 wt% of HY-10 is effective on natural gas hydrate inhibition. It is found through economic analysis that the use of HY-10 has obvious economi- cal advantage over methanol and Inhibex501. 展开更多
关键词 natural gas hydrate combined hydrate inhibitor kinetic hydrate inhibitors natural gas production
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Chemical resistance tests on PP-ternary nanocomposite for its application in bioreactor liner fabrication 被引量:1
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作者 FARIDA Yusof SALAWUDEEN T.Olalekan +2 位作者 QASIM H.Shah MA'AN F.Alkhatib SULEYMAN A.Muyibi 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第8期2217-2223,共7页
Continuous usage of bioreactor causes early degradation of most bioreactor liner materials due to the effects of various chemicals, consequently resulting in contamination in the bioprocess. Performance of PP-ternary ... Continuous usage of bioreactor causes early degradation of most bioreactor liner materials due to the effects of various chemicals, consequently resulting in contamination in the bioprocess. Performance of PP-ternary nanocomposite (PPTN) for its potential application in the fabrication of bioreactor liner material was investigated in this study. The chemical resistance of the composite samples obtained was tested by exposing them to chemicals such as acid, alkaline, water and bacterial solutions, according to ASTM 543-06, and their effects on the composite samples were carefully observed. Specifically, the investigation focused on the changes in the physico-mechanical properties of PPTN following long term of exposure to these chemicals. The results show slight increase in the weight and dimensions of samples in the first few days, followed by constant reading for the period of 4 weeks. The performance in terms of physical properties was in the range of PPTN with 0.61% MWCNT > PPTN 0.45% > PPTN 0.17%. The maximum percentage change in tensile properties, observed in this study, was approximately 10% against PPTN (0.17%), which indicates stable mechanical properties of the composite and invariably suggests that the nanocomposites could serve as a better alternative for bioreactor liner fabrication. 展开更多
关键词 BIOREACTOR chemical resistance liner material MWCNT melt intercalation polypropylene ternary nanocomposite
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Comparison of pretreatment,preservation and determination methods for foliar pH of plant samples 被引量:1
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作者 Sining Liu Jiashu Chen Wenxuan Han 《Journal of Plant Ecology》 SCIE CSCD 2022年第4期673-682,共10页
To compare current methods of pretreatment/determination for plant foliar pH,we proposed a method for longperiod sample preservation with little interference with the stability of foliar pH.Four hundred leaf samples f... To compare current methods of pretreatment/determination for plant foliar pH,we proposed a method for longperiod sample preservation with little interference with the stability of foliar pH.Four hundred leaf samples from 20 species were collected and four methods of pH determination were used:refrigerated(stored at 4°C for 4 days),frozen(stored at−16°C for 4 days),oven-dried and fresh green-leaf pH(control).To explore the effects of different leaf:water mixing ratio on the pH determination results,we measured oven-dried green-leaf pH by leaf:water volume ratio of 1:8 and mass ratio of 1:10,and measured frozen senesced-leaf pH by mass ratio of 1:10 and 1:15.The standard major axis regression was used to analyze the relationship and the conversion equation between the measured pH with different methods.Foliar pH of refrigerated and frozen green leaves did not signifcantly differ from that of fresh green-leaf,but drying always overrated fresh green-leaf pH.During the feld sampling,cryopreservation with a portable refrigerator was an advisable choice to get a precise pH.For long-duration feld sampling,freezing was the optimal choice,and refrigeration is the best choice for the shorttime preservation.The different leaf:water mixing ratio signifcantly infuenced the measured foliar pH.High dilution reduced the proton concentration and increased the measured pH.Our fndings provide the conversion relationships between the existing pretreatment and measurement methods,and establish a connection among pH determined by different methods.Our study can facilitate foliar pH measurement,thus contributing to understanding of this interesting plant functional trait. 展开更多
关键词 green/senesced leaf leaf pH plant functional traits sample preservation specifcation/standard/protocol leaf water ratio transformation/conversion equation
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