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科技商品“二因素”及其辩证统一——从马克思商品理论和劳动价值论维度的考察 被引量:2
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作者 刘冠军 《洛阳师范学院学报》 2008年第4期40-46,共7页
在现代科技商品经济社会中,占统治地位的社会财富表现为庞大的科技商品的堆积,而单个的科技商品表现为这种财富的元素形式。从马克思商品理论和劳动价值论的维度看,科技商品的"二因素"是科技使用价值和科技价值。科技使用价... 在现代科技商品经济社会中,占统治地位的社会财富表现为庞大的科技商品的堆积,而单个的科技商品表现为这种财富的元素形式。从马克思商品理论和劳动价值论的维度看,科技商品的"二因素"是科技使用价值和科技价值。科技使用价值是科技商品的基础性因素,它主要是从"物"的属性方面对科技商品进行考察的结果,它所展示的是科技商品的"物"的属性,在实质上所反映的是人与物的关系;科技使用价值与一般物质性商品的使用价值相比较,既有相同之处即"科技使用价值之一般",同时又表现出自身的独有的特征即"科技使用价值之特殊"。科技价值是科技商品的核心因素,它主要是从"人"的属性方面对科技商品进行考察的结果,它所体现的是科技商品的"人"的属性,在实质上所反映的是人与人的关系;科技价值与一般物质性商品的价值相比较,既有相同之处即"科技价值之一般",同时又表现出独特的属性和特征即"科技价值之特殊"。作为科技商品"二因素"的科技使用价值和科技价值,既相互区别、各不相同,又相互依赖、相互依存,有机结合在一起共同构成了科技商品,因此科技商品是科技使用价值和科技价值的辩证统一体。而这种辩证统一性,是从"物"的属性和"人"的属性相统一的角度进行考察的结果,在实质上体现的是科技商品之"物"的属性和"人"的属性的辩证统一的关系。 展开更多
关键词 科技商品 “二因素” “物”的属性 “人”的属性 马克思 商品理论 劳动价值论
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从“二因素”到“二重性”:论马克思经济学术语转换的内在逻辑--评晏智杰教授的《对财富与价值二分论的解析》
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作者 任洲鸿 《当代经济研究》 CSSCI 北大核心 2008年第9期27-31,共5页
从商品"二因素"到商品"二重性"之间的经济学术语转换体现了马克思实现理论批判的内在逻辑。其中,商品"二因素"对应商品的使用价值与交换价值,商品"二重性"对应商品的使用价值与价值。商品二重... 从商品"二因素"到商品"二重性"之间的经济学术语转换体现了马克思实现理论批判的内在逻辑。其中,商品"二因素"对应商品的使用价值与交换价值,商品"二重性"对应商品的使用价值与价值。商品二重性学说并没有在古典政治经济学家那里得到"明确表述",也没有随着李嘉图学派的解体而"终结",更不是将实物财富与价值财富"截然加以分裂"的学说。 展开更多
关键词 商品“二因素” 商品“二重性” 劳动重性 唯物辩证法 内在逻辑
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2012:世界经济的悬念与风险
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作者 王东 《开放导报》 CSSCI 北大核心 2012年第1期106-109,共4页
2011年世界经济经历大半年跌宕起伏后,临近年底仍笼罩在浓浓的阴霾中,世界经济复苏与停滞形成胶着态势。留给2012年世界经济的悬念是什么?各种风险的变化则是决定2012年世界经济走向的关键性因素。
关键词 复苏悬念 风险因素“二次探底”
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Potential risk factors for nonalcoholic steatohepatitis related to pancreatic secretions following pancreaticoduodenectomy 被引量:5
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作者 Sun Choon Song Seong Ho Choi +3 位作者 Dong Wook Choi Jin Seok Heo Woo Seok Kim Min Jung Kim 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第32期3716-3723,共8页
AIM: To identify risk factors for nonalcoholic steatohepatitis following pancreaticoduodenectomy, with a focus on factors related to pancreatic secretions. METHODS: The medical records of 228 patients who had a pancre... AIM: To identify risk factors for nonalcoholic steatohepatitis following pancreaticoduodenectomy, with a focus on factors related to pancreatic secretions. METHODS: The medical records of 228 patients who had a pancreaticoduodenectomy over a 16-mo period were reviewed retrospectively. The 193 patients who did not have fatty liver disease preoperatively were included in the final analysis. Hepatic steatosis was diagnosed using the differences between splenic and hepatic attenuation and liver-to-spleen attenuation as measured by non-enhanced computed tomography. RESULTS: Fifteen patients (7.8%) who showed postoperative hepatic fatty changes were assigned to Group A, and the remaining patients were assigned to Group B. Patient demographics, preoperative laboratory findings (including levels of C-peptide, glucagon, insulin and glucose tolerance test results), operation types, and final pathological findings did not differ significantly between the two groups; however, the frequency of pancreatic fistula (P = 0.020) and the method of pancreatic duct stenting (P = 0.005) showed significant differences between the groups. A multivari- ate analysis identified pancreatic fistula (HR = 3.332, P = 0.037) and external pancreatic duct stenting (HR = 4.530, P = 0.017) as independent risk factors for the development of postoperative steatohepatitis. CONCLUSION: Pancreatic fistula and external pancreatic duct stenting were identified as independent risk factors for the development of steatohepatitis following pancreaticoduodenectomy. 展开更多
关键词 Nonalcoholic fatty liver diseases Nonalcoholic steatohepatitis Pancreatic duct stenting Pancreatic fistula Pancreatic surgery
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Geochemical characteristics of Guizhou Permian coal measure strata and analysis of the control factors 被引量:11
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作者 YANG Rui-dong LIU Ling +2 位作者 WEI Huai-rui CUl Yu-chao CHENG Wei 《Journal of Coal Science & Engineering(China)》 2011年第1期55-68,共14页
Based on element geochemical studies of the main Permian exploitable coal measure strata in Western Guizhou, the element geochemical distribution characteristics of the main exploitable coal measures were revealed in ... Based on element geochemical studies of the main Permian exploitable coal measure strata in Western Guizhou, the element geochemical distribution characteristics of the main exploitable coal measures were revealed in the regions of Dafang, Qianxi, Weining, Hezhang, Zhijin, etc., of Guizhou Province, and the results show that their element contents are mainly affected by terrestrial material supply. Coal measures formed in the delta plain environment where sufficient terrestrial materials are supplied contain relatively abundant trace elements and rare-earth elements, whereas those formed in the tidal-fiat environment influenced greatly by seawater have relatively low contents of trace elements and rare-earth elements, mainly con- trolled by the geological fact that basalts the parent rocks from source regions contain high trace elements and rare-earth elements. In addition, coal measures affected by later hydrothermal activities and fault tectonics contain a large amount of harmful elements. According to the rules of distribution of elements in coal measures, a new idea was put forward to classify coal-forming environments by using the geochemical composition characteristics, which is of great significance in dissolving the problem of whether coal measures were fbrmed either in delta environments or in tidal-flat environments in Western Gui- zhou. At the same time, the rules of distribution of elements in the main exploitable coal measures in Western Guizhou were fully understood, which is of direct significance in utilizing coal resources on the basis of classification of coals, as well as in developing the coal chemical industry. 展开更多
关键词 element geochemistry sedimentary environment major exploitable coal measures PERMIAN Western Guizhou
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Early graft dysfunction following adult-to-adult livingrelated liver transplantation:Predictive factors and outcomes 被引量:2
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作者 Salvatore Gruttadauria Fabrizio di Francesco +7 位作者 Giovanni Battista Vizzini Angelo Luca Marco Spada Davide Cintorino Sergio Li Petri Giada Pietrosi Duilio Pagano Bruno Gridelli 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第36期4556-4560,共5页
AIM:To describe a condition that we define as early graft dysfunction(EGD)which can be identified preoperatively. METHODS:Small-for-size graft dysfunction following living-related liver transplantation(LRLT)is charact... AIM:To describe a condition that we define as early graft dysfunction(EGD)which can be identified preoperatively. METHODS:Small-for-size graft dysfunction following living-related liver transplantation(LRLT)is characterized by EGD when the graft-to-recipient body weight ratio(GRBWR)is below 0.8%.However, patients transplanted with GRBWR above 0.8%can develop dysfunction of the graft.In 73 recipients of LRLT(GRBWR>0.8%),we identified 10 patients who developed EGD.The main measures of outcomes analyzed were overall mortality,number of re-transplants and length of stay in days(LOS).Furthermore we analyzed other clinical pre-transplant variables,intraoperative parameters and post transplant data.RESULTS:A trend in favor of the non-EGD group(3-mo actuarial survival 98%vs 88%,P=0.09;3-mo graft mortality 4.7%vs 20%,P=0.07)was observed as well as shorter LOS(13 d vs 41.5 d;P=0.001)and smaller requirement of peri-operative Units of Plasma (4 vs 14;P=0.036).Univariate analysis of pre- transplant variables identified platelet count,serum bilirubin,INR and Meld-Na score as predictors of EGD. In the multivariate analysis transplant Meld-Na score (P=0.025,OR:1.175)and pretransplant platelet count(P=0.043,OR:0.956)were independently associated with EGD. CONCLUSION:EGD can be identified preoperatively and is associated with increased morbidity after LRLT. A prompt recognition of EGD can trigger a timely treatment. 展开更多
关键词 Small-for-size graft dysfunction Livingrelated liver transplantation Graft-to-recipient bodyweight ratio Partial liver transplantation Allograftdysfunction
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Prime Factorization in the Duality Computer 被引量:8
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作者 WANG Wan-Ying SHANG Bin +1 位作者 WANG Chuan LONG Gui-Lu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期471-473,共3页
We give algorithms to factorize large integers in the duality computer. We provide three duality algorithms for factorization based on a naive factorization method, the Shor algorithm in quantum computing, and the Fer... We give algorithms to factorize large integers in the duality computer. We provide three duality algorithms for factorization based on a naive factorization method, the Shor algorithm in quantum computing, and the Fermat's method in classical computing. All these algorithms may be polynomial in the input size. 展开更多
关键词 duality computer prime factorization Fermat's method
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The Enhancement of CO2 Chemical Absorption by K2CO3 Aqueous Solution in the Presence of Activated Carbon Particles 被引量:10
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作者 卢素敏 马友光 +1 位作者 朱春英 沈树华 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第6期842-846,共5页
The enhancement of chemical absorption of CO2 by K2CO3/H2O absorbents in the presence of activated carbon (AC) particles was investigated. The results show that the gas absorption rates can be enhanced significantly... The enhancement of chemical absorption of CO2 by K2CO3/H2O absorbents in the presence of activated carbon (AC) particles was investigated. The results show that the gas absorption rates can be enhanced significantly in the presence of AC particles, and the maximum enhancement factor 3.7 was observed at low stirring intensities. The enhancement factor increased rapidly with the solid loading during the initial period of absorption and then be- came mild gradually to a maximum value. Both the liquid-solid contact area and the probability of solid particles residing at the gas-liquid interface decreased with the increase of the particle size, leading to a negative effect on the enhancement of mass transfer. The influence of the particles on gas absorption decreased with the reaction rate. The stirring speed changed the interfacial coverage and mass transfer rate on the liquid side and consequently affected the mass transfer between the gas and liquid phases; the enhancement factor decreased with the stirring intensity. A heterogeneous two-zone model was proposed for predicting the enhancement factor and the calculated results agreed well with the experimental data. 展开更多
关键词 chemical absorption enhancement factor mass transfer activated carbon particle
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Enrichment of Resveratrol in Wine through a New Vinification Procedure 被引量:2
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作者 Raul Francisco Pastor Magdalena Raquel Gargantini +6 位作者 Marcelo Murgo Sebastian Prieto Humberto Manzano Carla Aruani Claudia In6s Quini Maria-Isabel Covas Roberto H6ctor Iermoli 《Journal of Life Sciences》 2015年第7期327-333,共7页
Sulphur dioxide is used in the vinification process as an antimicrobial agent, but it is also considered as an important risk factor for liver diseases. Stilbenes have inhibitory effects on the growth of lactic acid b... Sulphur dioxide is used in the vinification process as an antimicrobial agent, but it is also considered as an important risk factor for liver diseases. Stilbenes have inhibitory effects on the growth of lactic acid bacteria strains isolated from wine. The authors investigated the viability of obtaining free-SO2 resveratrol-enriched red wines. Substitution of sulfite (7 g/100kg) for resveratrol (150 mg/L and 300 mg/L) in the vinification process did not change the basic physical and chemical properties of wine or its sensorial profile To the best of the authors' knowledge this is the first time that this type of vinification procedure is reported. 展开更多
关键词 Vinification sulfur dioxide RESVERATROL WINE enrichment.
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STUDY ON OBESITY RELATED FACTORS: FFA, LEPTIN AND ADIPONECTIN IN SUBJECTS WITH VARYING GLUCOSE TOLERANCE 被引量:1
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作者 顾卫琼 洪洁 +3 位作者 张翼飞 宁光 陈名道 唐金凤 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2005年第1期18-22,共5页
Objective To study the fasting serum levels of obesity related factors: FFA, leptin and adi-ponectin in subjects with varying glucose tolerance and their relationship with BMI, insulin sensitivity index and isletbeta-... Objective To study the fasting serum levels of obesity related factors: FFA, leptin and adi-ponectin in subjects with varying glucose tolerance and their relationship with BMI, insulin sensitivity index and isletbeta-cell function. Methods Serum levels of FFA, leptin and adiponectin in 24 normal, 32 simple obese, 34IGT and 36 T2DM subjects were measured by ACS-ACOD assay or RIA. Results The serum levels of leptin andFFA in three groups:simple obese, IGT and DM were much higher than those in normal control (P <0. 001). Incontrast, serum level of adiponectin of simple obese, IGT and DM groups were significant lower than that of normalcontrol, among them DM subjects had the lowest level (P <0. 001). Correlation analysis showed that FFA was pos-itively correlated to BMI, WHR, FBG, fasting insulin level and negatively correlated to SI; adiponectin was negativelycorrelated to BMI, WHR, FBG, PBG, but positively correlated to SI and AIRg; and leptin was positively correlated toBMI, fasting insulin and AIRg when negatively correlated to FBG and SI. None of them was correlated to age.Conclusion Subjects with insulin resistance have high serum FFA and leptin levels but low serum adiponectin level.With the glucose tolerance deterioration, serum FFA level increases much higher while the adiponectin deceases muchlower. Unlike insulin, none of these obesity related factors can be used as the simple indicating or determining factorof SI, though each of them, to different extent, takes part in the development of insulin resistance. 展开更多
关键词 FFA leptin adiponectin glucose tolerance obesity
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Root Causes of China’s Trade Surplus and How to Balance It
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作者 华民 《China Economist》 2015年第1期26-30,共5页
This paper explains the root cause of China's trade surplus and argues that it is rooted in structural factors. China's dual economic structure and the relatively slow growth in wages due to the abundant supply of l... This paper explains the root cause of China's trade surplus and argues that it is rooted in structural factors. China's dual economic structure and the relatively slow growth in wages due to the abundant supply of labor have led to a large supply glut between China's domestic demand and output, which has been balanced by export. This is a structural problem that cannot be solved by currency appreciation or the readjustment of capital account deficits. A potentially viable option is to adjust the current account by developing a new opening-up system featuring more freedom and compliance. 展开更多
关键词 trade surplus capital account deficit current account adjustment opening-up
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Driving Factors for Forest Fire Occurrence in Durango State of Mexico:A Geospatial Perspective 被引量:3
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作者 Diana Avila-Flores Marin Pompa-Garcia +3 位作者 Xanat Antonio-Nemiga Dante A Rodriguez-Trejo Eduardo Vargas-Perez Javier Santillan-Perez 《Chinese Geographical Science》 SCIE CSCD 2010年第6期491-497,共7页
Forest fire is one of the major causes of forest loss and therefore one of the main constraints for sustainable forest management worldwide.Identifying the driving factors and understanding the contribution of each fa... Forest fire is one of the major causes of forest loss and therefore one of the main constraints for sustainable forest management worldwide.Identifying the driving factors and understanding the contribution of each factor are essential for the management of forest fire occurrence.The objective of this study is to identify variables that are spatially related to the occurrence and incidence of the forest fire in the State of Durango,Mexico.For this purpose,data from forest fire records for a five-year period were analyzed.The spatial correlations between forest fire occurrence and intensity of land use,susceptibility of vegetation,temperature,precipitation and slope were tested by Geographically Weighted Regression(GWR) method,under an Ordinary Least Square estimator.Results show that the spatial pattern of the forest fire in the study area is closely correlated with the intensity of land use,and land use change is one of the main explanatory variables.In addition,vegetation type and precipitation are also the main driving factors.The fitting model indicates obvious link between the variables.Forest fire was found to be the consequence of a particular combination of the environmental factors,and when these factors coexist with human activities,there is high probability of forest fire occurrence.Mandatory regulation of human activities is a key strategy for forest fire prevention. 展开更多
关键词 forest fire Geographically Weighted Regression(GWR) land use forest management Durango State Mexico
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Metabolic and Anthropometric Effects of NADH RAPID ENERGY in Diabetic Type 2
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作者 Rahal Lotfi Joerg George Birkmayer Ahmed Ghouini 《Journal of Food Science and Engineering》 2016年第5期280-285,共6页
Twenty patients with diabetes type-2, aged between 38 and 61 years, with at least one cardiovascular risk factor were divided in two groups (Group-1 included newly diagnosed type 2 diabetic patients without treatment... Twenty patients with diabetes type-2, aged between 38 and 61 years, with at least one cardiovascular risk factor were divided in two groups (Group-1 included newly diagnosed type 2 diabetic patients without treatment with oral antidiabetic OAD, Group-2: patients with diabetes type 2 under OAD +/- insulin (N = 11)). Patients from both groupswere taking Nicotinamide Adenine Dinucleotide (NADH) Rapid Energy 80 mg/day in two takes for a period of 56 days. A greater reduction in average fasting glucose and HbAlc after 56 days was observed in the patients of group 1 not taking metformin compared to patients of group-2 which were taking metformin. Why metformin reduces the anti-diabetic effect of NADH will be discussed. 展开更多
关键词 NADH Coenzmye-1 diabetes type 2 metabolic profile ANTHROPOMETRY mitochondrial diseases.
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Ultrastructural Study of Dermatic Tissues in Secondary Syphilis
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作者 张晓东 脱朝伟 +1 位作者 张庆瑞 宋芳吉 《Chinese Journal of Sexually Transmitted Infections》 2001年第2期38-40,共3页
Objective: For the purpose of understanding the changingprocess of syphilis histomorphology and its injury mechanism,the ultrastructure of dermatic tissues of secondary syphiliswas studied. Methods: Different skin inj... Objective: For the purpose of understanding the changingprocess of syphilis histomorphology and its injury mechanism,the ultrastructure of dermatic tissues of secondary syphiliswas studied. Methods: Different skin injury tissues of secondary syphilispatients, whose serum RPR and TPHA tests in the lab bothappeared positive reaction, were observed throughtransmission electron microscope(TEM). Results: Inflammations appeared on epidermides and coria,a great deal of neutrocytes, lymphocytes and a small amountof plasma innltrated them. Karyopyknosis, karyorrhexis,epicyte lysis and mitochondrion vacular degenerationoccurred. Spirocheta pallida was distributed on intercellularsubstances, epicytes and collagenous fibers. The epicytes werepressed to foveation. Conclusion The pathological change ofcharacteristic tissue ultrastructure reported here is ahistomorphological foundation to study the organism injurymechanism caused by syphilis. 展开更多
关键词 secondary syphilis dermatic tissue ULTRASTRUCTURE
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Recognition of Production and Morphological Traits in Macoei Sheep Breed
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作者 A. Lavvaf M. B. Zandi 《Journal of Agricultural Science and Technology(A)》 2011年第8期1314-1317,共4页
In this study, the data of Macoei sheep from 1994 to 2008 were collected in Affair Animal Breeding Unit, Agriculture Organization of West Azerbijan province of Iran for recognition of reproductive and morphological ch... In this study, the data of Macoei sheep from 1994 to 2008 were collected in Affair Animal Breeding Unit, Agriculture Organization of West Azerbijan province of Iran for recognition of reproductive and morphological characteristics. The trait in this research include birth weight (BW), 3 (W3), 6 (W6), 9 (W9), 12 (W12) months weight, fleece weight (WF) (as production traits), body length(BL), size of femur(F), thorax(TX), testis(TS), height of lumber(L) and shoulder(SH) (as morphological traits). Variance components, least square means and standard error of production and morphological traits were estimated and environmental factors (including effects of year of birth, season, sex, type of birth and age of dam) were studied with GLM procedure of SAS 9.1 software. The results showed that the all environmental factors have significant effect, male lambs weight more than females, and twins were more performance than single. Production and apparent performance characteristics of phenotypic traits was different in year of birth, maternal age, season. This study shows that Macoie sheep breed at the various management environment have suitable performance and genetic potential. 展开更多
关键词 Macoei sheep production and morphological traits variance component.
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The spatial distribution of commuting CO_2 emissions and the influential factors:A case study in Xi'an,China 被引量:2
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作者 LIU Yuan-Yuan WANG Yuan-Qing +1 位作者 AN Rui LI Chao 《Advances in Climate Change Research》 SCIE CSCD 2015年第1期46-55,共10页
As the transport sector is a major source of greenhouse gas emissions, the effect of urbanization on transport CO2 emissions in developing cities has become a key issue under global climate change. Examining the case ... As the transport sector is a major source of greenhouse gas emissions, the effect of urbanization on transport CO2 emissions in developing cities has become a key issue under global climate change. Examining the case of Xi'an, this paper aims to explore the spatial distribution of commuting CO2 emissions and influencing factors in the new, urban industry zones and city centers considering Xi'an's transition from a monocentric to a polycentric city in the process of urbanization. Based on household survey data from 1501 respondents, there are obvious differences in commuting CO2 emissions between new industry zones and city centers: City centers feature lower household emissions of 2.86 kg CO2 per week, whereas new industry zones generally have higher household emissions of 3.20 kg CO2 per week. Contrary to previous research results, not all new industry zones have high levels of CO2 emissions; with the rapid development of various types of industries, even a minimum level of household emissions of 2.53 kg CO2 per week is possible. The uneven distribution of commuting CO2 emissions is not uniformly affected by spatial parameters such as job-housing balance, residential density, employment density, and land use diversity. Optimum combination of the spatial parameters and travel pattern along with corresponding transport infrastructure construction may be an appropriate path to reduction and control of emissions from commuting. 展开更多
关键词 Sustainable urbanization Spatial distribution FACTORS Commuting CO2 emissions Xi'an
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Influence factors on thermal conductivity of ammonia-water nanofluids 被引量:4
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作者 杨柳 杜垲 张小松 《Journal of Central South University》 SCIE EI CAS 2012年第6期1622-1628,共7页
In order to investigate the mechanism of nanoparticles enhancing the heat and mass transfer of the ammonia-water absorption process,several types of binary nanofluids were prepared by mixing Al2O3 nanoparticles with p... In order to investigate the mechanism of nanoparticles enhancing the heat and mass transfer of the ammonia-water absorption process,several types of binary nanofluids were prepared by mixing Al2O3 nanoparticles with polyacrylic acid(PAA),TiO2 with polyethylene glycol(PEG 1000),and TiN,SiC,hydroxyapatite(noodle-like) with PEG 10000 to ammonia-water solution,respectively.The thermal conductivities were measured by using a KD2 Pro thermal properties analyzer.The influences of surfactant and ammonia on the dispersion stabilities of the binary nanofluids were investigated by the light absorbency ratio index methods.The results show that the type,content and size of nanoparticles,the temperature as well as the dispersion stability are the key parameters that affect the thermal conductivity of nanofluids.For the given nanoparticle material and the base fluid,the thermal conductivity ratio of the nanofluid to the ammonia-water liquid increases as the nanoparticle content and the temperature are increased,and the diameter of nanoparticle is decreased.Furthermore,the thermal conductivity ratio increases significantly by improving the stabilities of nanofluids,which is achieved by adding surfactants or performing the proper ammonia content in the fluid. 展开更多
关键词 binary nanofluids AMMONIA-WATER thermal conductivity size effect dispersion stability
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Synthesis of Vanillin 1, 2-Propylene Glycol Acetal Catalyzed by H3PMo6W6O40·nH2O 被引量:1
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作者 Zongrui Liu Zhe Dong Xiaohong Wang Lijuan Xie Limei Duan 《Journal of Chemistry and Chemical Engineering》 2010年第2期22-26,共5页
Vanillin 1, 2-propylene glycol acetal was synthesized from vanillin and 1, 2-propylene glycol using H3PMo6W6O40·nH2O as catalyst, The factors influencing the synthesis were discussed and the better reaction condi... Vanillin 1, 2-propylene glycol acetal was synthesized from vanillin and 1, 2-propylene glycol using H3PMo6W6O40·nH2O as catalyst, The factors influencing the synthesis were discussed and the better reaction conditions were found as follows: The amount of vanillin was 3.8 g, the molar ratio of vanillin was 1, 2-propylene glycol 1.0 to 2.4, the amount of catalyst was 1.6% in proportion to the total reacting materials, the volume ofcyclohexane as the water-carrying agent 4 mL, the refluxing time was 2 h at 88-96℃ and thus the product yield reached over 87%. The results show that the catalyst's activity is high and the reaction time is short. 展开更多
关键词 Vanillin 1 2-propylene glycol acetal H3PMo6W6O40 polyoxometalate catalysis.
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Bio-Demographic Factors Impacting on Employment in Namibia: A Binary Logistic Regression Model.
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作者 Camilla Tjikune Lillian Pazvakawambwa 《Journal of Mathematics and System Science》 2013年第9期426-436,共11页
Despite concerted efforts to create employment opportunities and the realized economic growth between 2000 and 2005, the unemployment rate in Namibia currently stands at 27.4%, according to the Labour Force Survey rel... Despite concerted efforts to create employment opportunities and the realized economic growth between 2000 and 2005, the unemployment rate in Namibia currently stands at 27.4%, according to the Labour Force Survey released in April 2013. The percentage of employed males in Namibia stands at 41.6% while that of employed females stand at 28.8% according to the National Human Resources Plan of May 2013. Analysts have put the blame on adverse climatic conditions, limited levels of skills, access to finance, and the structure of the economy. The frustration and discomfort caused by unemployment, especially among the youth, can threaten the country's peace and stability as it negatively impacts on the standard of living, crime rates, family happiness, and drug abuse.To date, studies on employment in Namibia have mainly concentrated on the micro and macro econometric approaches. It is important to examine how bio-demographic characteristics affect employment. This paper uses data from the 2010 Income and expenditure survey to establish the bio-demographic determinants of employment by fitting a binary logistic model. The outcome variable is employment status which is dichotomous. The independent variables which were guided by review of related literature and availability of data in the Income and Expenditure survey data set, included age-group, region, place of residence, marital status, education level, and gender. Results indicated that employment prospects in Namibia were influenced by the region, gender, marital status, and education level. 展开更多
关键词 EMPLOYMENT Namibia logistic regression
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Variation in Rubisco and other photosynthetic parameters in the life cycle of Haematococcus pluvialis
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作者 CHEN Zhangfan WANG Guangce NIU Jianfeng 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第1期136-145,共10页
Cells of Haematococcus pluvialis Flot. et Will were collected in four different growth phases. We quantified the initial and total enzyme activity of ribulose-1,5-bisphosphate carboxylase (Rubiseo) in crude extracts... Cells of Haematococcus pluvialis Flot. et Will were collected in four different growth phases. We quantified the initial and total enzyme activity of ribulose-1,5-bisphosphate carboxylase (Rubiseo) in crude extracts, and the relative expression of large-subunit ribulose-1,5-bisphosphate caboxylase / oxygenase (rbcL) mRNA. We measured the ratio of photosynthetic rate to respiration rate (P/R), maximal effective quantum yield of photosystem II (Fv/Fm), electron transport rate (ETR), actual photochemical efficiency of PSI1 in the light (ФPSII), and non-photochemical quenching (NPQ). Green vegetative cells were found to be in the most active state, with a relatively higher P/R ratio. These cells also displayed the lowest NPQ and the highest Fv/Fm, ETR, and ФPSII, indicating the most effective PSII. However, both Rubisco activity and rbcL mRNA expression were the lowest measured. In orange resting cysts with relatively lower P/R and NPQ, Rubisco activity and rbcL expression reached a peak, while Fv/Fm, ETR, and ФPSII were the lowest measured. Taking into account the methods of astaxanthin induction used in industry, we suggest that Rubisco may participate in astaxanthin accumulation in H. pluvialis. A continuous and sufficient supply of a carbon source such as CO2 may therefore aid the large scale production of astaxanthin. 展开更多
关键词 Haematococcus pluvialis RUBISCO ASTAXANTHIN life cycle growth phase
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