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连铸混浇坯的过度时间及影响因素 被引量:6
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作者 陆云威 崔素兰 《炼钢》 CAS 北大核心 1995年第4期30-33,12,共5页
为提高连铸比实现全连铸,鞍钢二炼钢在小方坯连浇不同钢种过渡段铸坯成分差异上做了试验研究,并指出小方坯连铸机增设钢水快速分析和快速调节装置的必要性。
关键词 小方坯连铸机 混浇坯 试验 过度时间
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保险享有能缓解农民工过度劳动吗? 被引量:2
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作者 杨术 黄怡丹 赵昕东 《浙江学刊》 CSSCI 北大核心 2022年第3期144-150,共7页
我国农民工群体的工作时间普遍过长,存在过度劳动问题。本文基于2016和2017年中国乡城人口流动调查数据,建立了农民工过度劳动选择和过度劳动时间面板固定效应模型,实证研究了保险享有对农民工群体过度劳动的影响。研究结果显示,保险享... 我国农民工群体的工作时间普遍过长,存在过度劳动问题。本文基于2016和2017年中国乡城人口流动调查数据,建立了农民工过度劳动选择和过度劳动时间面板固定效应模型,实证研究了保险享有对农民工群体过度劳动的影响。研究结果显示,保险享有能够有效降低农民工群体过度劳动的概率,有助于缩减该群体过度劳动及重度过度劳动的时间。据此,为有效缓解农民工群体的过度劳动,政府部门在严格限制劳动者的工作时间和规范加班工资制度的同时,还应采取措施保证农民工群体享有基本保险。 展开更多
关键词 农民工 过度劳动 保险享有 过度劳动时间
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The Neglected Significance of Glomerular Density as a 5-year Progression Indicator for IgA Nephropathy 被引量:4
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作者 陈振杰 李航 +8 位作者 蔡建芳 张鑫 李超 邹佩美 李明喜 陈丽萌 李雪梅 李学旺 文煜冰 《Chinese Medical Sciences Journal》 CAS CSCD 2017年第3期145-151,共7页
Objective To investigate whether glomerular density (GD) could be an independent prognostic factor for patients of IgA nephropathy with estimated glomerular filtration rate (eGFR) of 30 to 60 ml/min per 1.73 m2, ... Objective To investigate whether glomerular density (GD) could be an independent prognostic factor for patients of IgA nephropathy with estimated glomerular filtration rate (eGFR) of 30 to 60 ml/min per 1.73 m2, or for patients with time-average proteinuria 〈 0.5 g/d. Methods A total of 173 patients with biopsy-confirmed IgA nephropathy diagnosed from January 2000 to December 2010 were included. All of these patients were followed up for more than 5 years. The endpoint was a 〉 30% of decline in eGFR from baseline after 5-year follow-up. The optimal cut-off value of GD was calculated by ROC curve. Kaplan-Meier method and Cox regression analysis was used for survival analysis. Results A 30% of decline in eGFR occurred in 14.5% of all patients. The optimal diagnostic cut-off value of GD was 1.99/mm2 (AUC = 0.90, sensitivity = 84.0%, specificity = 81.8%) determined by ROC curve. The low GD group (GD 〈 1.99 per mm2) experienced a significant increase in renal endpoint for patients with eGFR of 30 to 60 ml/min per 1.73 m2 (six patients in lower GD group, while one patient in the other group). For patients with time-average proteinuria 〈 0.5 g/d, the lower GD group showed a higher eGFR decline from baseline (4.5±16.7 ml/min per 1.73 m2 vs. –8.1±21.4 ml/min per 1.73 m2, P = 0.038); two patients in this group reached the endpoint, while no patients in the higher GD group did. Conclusion GD could be an independent prognostic factor for patients of IgA nephropathy with eGFR at 30 to 60 ml/min per 1.73 m2 of body surface, particularly for those with time-averaged amount of urine protein less than 0.5 g per day. 展开更多
关键词 glomerular density IgA nephropathy renal progression
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频谱音乐的曲式原则 被引量:1
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作者 肖武雄 《星海音乐学院学报》 CSSCI 2012年第4期131-141,共11页
曲式通常表示音乐的"时空结构",频谱音乐对此的最大贡献是通过仪器分析,频谱显现,使得这本来属于纯理论范畴的内容,成为了一种可视的、具有生命力的"视在声源"。自此,我们不仅可以用文本分析去了解曲式,用耳朵去感... 曲式通常表示音乐的"时空结构",频谱音乐对此的最大贡献是通过仪器分析,频谱显现,使得这本来属于纯理论范畴的内容,成为了一种可视的、具有生命力的"视在声源"。自此,我们不仅可以用文本分析去了解曲式,用耳朵去感受曲式,还增加了一种重要的方法———用眼睛去实事观察声音状态由生到死的变化全过程。文章从时间过渡性原则、自我繁殖与自我破坏(阻断)原则、可预测与不可预测原则,以及协和序进原则等四个方面,对频谱音乐的曲式领域进行研究。 展开更多
关键词 频谱 曲式 时间过度 协和序进
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Multiscale entropy:A tool for understanding the complexity of postural control 被引量:5
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作者 Michael A.Busa Richard E.A.van Emmerik 《Journal of Sport and Health Science》 SCIE 2016年第1期44-51,共8页
Clinical disorders often are characterized by a breakdown in dynamical processes that contribute to the control of upright standing.Disruption to a large number of physiological processes operating at different time s... Clinical disorders often are characterized by a breakdown in dynamical processes that contribute to the control of upright standing.Disruption to a large number of physiological processes operating at different time scales can lead to alterations in postural center of pressure(Co P)fluctuations.Multiscale entropy(MSE) has been used to identify differences in fluctuations of postural Co P time series between groups with and without known physiological impairments at multiple time scales.The purpose of this paper is to:1) review basic elements and current developments in entropy techniques used to assess physiological complexity;and 2) identify how MSE can provide insights into the complexity of physiological systems operating at multiple time scales that underlie the control of posture.We review and synthesize evidence from the literature providing support for MSE as a valuable tool to evaluate the breakdown in the physiological processes that accompany changes due to aging and disease in postural control.This evidence emerges from observed lower MSE values in individuals with multiple sclerosis,idiopathic scoliosis,and in older individuals with sensory impairments.Finally,we suggest some future applications of MSE that will allow for further insight into how physiological deficits impact the complexity of postural fluctuations;this information may improve the development and evaluation of new therapeutic interventions. 展开更多
关键词 Aging Movement disabilities Multiscale entropy Postural control Sensory loss
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The Onset of the Monsoon over the Bay of Bengal:The Year-to-Year Variations 被引量:7
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作者 YU Wei-Dong LI Kui-Ping +3 位作者 SHI Jian-Wei LIU Lin WANG Hui-Wu LIU Yan-Liang 《Atmospheric and Oceanic Science Letters》 2012年第4期342-347,共6页
In situ buoy observation data spanning four years(2008-2011) were used to demonstrate the year-to-year variations of the monsoon onset processes in the Bay of Bengal(BoB).A significant early(late) monsoon onset event ... In situ buoy observation data spanning four years(2008-2011) were used to demonstrate the year-to-year variations of the monsoon onset processes in the Bay of Bengal(BoB).A significant early(late) monsoon onset event in 2009(2010) was analyzed in detail.It is found that the year-to-year variations of monsoon onset can be attributed to either the interannual variability in the BoB SST or the irregular activities of the intra-seasonal oscillation(ISO).This finding raises concern over the potential difficulties in simulating or predicting the monsoon onset in the BoB region.This uncertainty largely comes from the unsatisfactory model behavior at the intra-seasonal time scale. 展开更多
关键词 monsoon onset interannual variations Bay of Bengal SST
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Determination of metastable zone and induction time of analgin for cooling crystallization 被引量:7
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作者 Ling Zhou Zhao Wang +3 位作者 Meijing Zhang Mingxia Guo Shijie Xu Qiuxiang Yin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第3期313-318,共6页
The solubility, metastable zone width, and induction time of analgin for unseeded batch cooling crystallization in ethanol–aqueous system were experimentally determined. The solubility data could be well described by... The solubility, metastable zone width, and induction time of analgin for unseeded batch cooling crystallization in ethanol–aqueous system were experimentally determined. The solubility data could be well described by the van't Hoff equation model. The metastable zone width at various cooling rates was measured, and some parameters of nucleation kinetic were calculated using the Ny'vlt theory. Furthermore, the induction period of various temperatures and supersaturation ratios was also measured. According to classical nucleation theory, some nucleation parameters and interfacial energy was calculated through the induction time(t_(ind)) data. Homogeneous nucleation tended to occur when the supersaturation is high, whereas heterogeneous nucleation was more likely to occur when the supersaturation is low. 展开更多
关键词 ANALGIN Cooling crystallization Primary nucleation Metastable zone Induction time
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Study on Collecting Efficiency of Lube-oil Filtration Media
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作者 付海明 苏小红 《Journal of Donghua University(English Edition)》 EI CAS 2009年第4期374-378,共5页
We made an experimental study and analysis on the relationships between filtration collecting efficiency and porosity, fiber diameter, and particles diameters for differential porosity media when fibrous media collect... We made an experimental study and analysis on the relationships between filtration collecting efficiency and porosity, fiber diameter, and particles diameters for differential porosity media when fibrous media collecting lube-oil. The influencing extent of porosity, dust concentration, and velocity impacting on collecting efficiency were researched by orthogonal experimental test. The results showed that porosity had the best salience affection on collecting efficiency, and the affection of velocity and dust concentration was less. The main factors of impacting on collecting efficiency were porosity, fiber diameter, particles diameter, dust concentration, filtration time and filtration velocity. The correlation formula between collecting efficiency and porosity, aperture diameter, fiber diameter, particles diameter, the thickness of media, and filtration time was obtained. It can forecast the collecting efficiency of lube-oil filtration media and provide a guide for selecting suitable fibrous filtration media. 展开更多
关键词 lube-oil filtration media collecting efficiency orthogonal experiment
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Sinking of particulates ^(234)Th_(xs),~7Be and ^(210)Pb_(xs) in the Changjiang estuary,China
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作者 黄德坤 杜金洲 +2 位作者 吴云峰 李道季 张经 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第6期1152-1159,共8页
The time scale of transport and reaction processes in the ocean can be evaluated using natural radionuclides of different half-lives.In the present study,we evaluated the residence times of particulate reactive radion... The time scale of transport and reaction processes in the ocean can be evaluated using natural radionuclides of different half-lives.In the present study,we evaluated the residence times of particulate reactive radionuclides 7 Be,210 Pb xs and 234 Th in the Changjiang (Yangtze River) estuary,which is a high turbidity estuary,in June,2006.The residence times of particulate 7 Be,234 Th xs and 210 Pb xs in the Changjiang estuary were calculated to be 0.7-20.4,0.18-4.1 and 0.6-89.8 d,respectively.The obtained residence times of those nuclides are comparable with those of other estuaries and bays.For 234 Th xs and 7 Be,the residence times decreased with increasing concentrations of suspended particulate matter (SPM);however,those of 210 Pb xs increased.Moreover,scavenging residence times of 234 Th and 7 Be increased from coast to offshore,while those of 210 Pb xs decreased. 展开更多
关键词 thorium-234 beryllium-7 lead-210 residence times Changjiang (Yangtze River) estuary
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A New Codebook Design Scheme for Fast Beam Searching in Millimeter-Wave Communications 被引量:1
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作者 ZOU Weixia GUO Chao +2 位作者 DU Guanglong WANG Zhenyu GAO Ying 《China Communications》 SCIE CSCD 2014年第6期12-22,共11页
To overcome imperfection of exhaustive based beam searching scheme in IEEE 802.15.3c and IEEE 802.11 ad and accelerate the beam training process, combined with the fast beam searching algorithm previously proposed, th... To overcome imperfection of exhaustive based beam searching scheme in IEEE 802.15.3c and IEEE 802.11 ad and accelerate the beam training process, combined with the fast beam searching algorithm previously proposed, this paper proposed a beam codebook design scheme for phased array to not only satisfy the fast beam searching algorithm's demand, but also make good use of the advantage of the searching algorithm. The simulation results prove that the proposed scheme not only performs well on flexibility and searching time complexity, but also has high success ratio. 展开更多
关键词 wireless communication 60GHz phased array BEAM-FORMING beam searching beam codebook design
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A unified approach of PID controller design for unstable processes with time delay
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作者 Ashraf RAZA Md Nishat ANWAR 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第9期2643-2661,共19页
This paper addresses a unified approach of the PID controller design for low as well as high order unstable processes with time delay.The design method is based on the direct synthesis(DS)approach to achieve the enhan... This paper addresses a unified approach of the PID controller design for low as well as high order unstable processes with time delay.The design method is based on the direct synthesis(DS)approach to achieve the enhanced load disturbance rejection.To improve the servo response,a two-degree of freedom control scheme has been considered.A suitable guideline has been provided to select the desired reference model in the DS scheme.The direct synthesis controller has been approximated to the PID controller using the frequency response matching method.A consistently better performance has been obtained in comparison with the recently reported methods. 展开更多
关键词 unstable process maximum sensitivity time delay higher order process direct synthesis method frequency response matching
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Expression and significance of cyclooxygenase-2 in human lung cancer
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作者 Weiying Li Wentao Yue +7 位作者 Niu Niu Lina Zhang Xiaoting Zhao Li Ma Xuehui Yang Chunyan Zhang Yue Wang Meng Gu 《The Chinese-German Journal of Clinical Oncology》 CAS 2014年第5期203-206,共4页
Objective: We aimed to examine the expression of cyclooxygenase-2 and the relationship with the pathological types, TNM stage, lymph node metastasis, the degree of differentiation, smoking and the survival. Methods: I... Objective: We aimed to examine the expression of cyclooxygenase-2 and the relationship with the pathological types, TNM stage, lymph node metastasis, the degree of differentiation, smoking and the survival. Methods: Immunohistochemical staining method was used to examine the expression of cyclooxygenase-2 of 121 cases of lung cancer and three control groups. The data were statistically analyzed. Results: Compared with the health group, cyclooxygenase-2 was over expressed in the inflammatory tissue(P = 0.036), lung adenocarcinoma(P = 0.005) and squamous carcinoma(P = 0.047). Compared with patients without lymph node metastasis, cyclooxygenase-2 was over expressed(P = 0.033) in patients with lymph node metastasis. Compared with high differentiation group, cyclooxygenase-2 was over expressed(P = 0.004) in low differentiation group. Compared with non-smokers, the expression of cyclooxygenase-2 increased in smokers(P = 0.000). The median survival time of patients that the expression of cyclooxygenase-2 were negative was 9 months(95% CI, 5.6–12.4 months). The median survival time of patients that the expression of cyclooxygenase-2 were positive was 5 months(95% CI, 3–7 months). They was statistical difference(P = 0.001). Conclusion: Overexpression of cyclooxygenase-2 is associated with pathological types, TNM stage, lymph node metastasis, degrees of differentiation, smoking and prognosis in lung cancer. 展开更多
关键词 CYCLOOXYGENASE-2 lung neoplasms IMMUNOHISTOCHEMISTRY
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Mechanisms of resistance to trastuzumab:an updated review 被引量:1
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作者 Yan Zhang Jinsheng Zhang 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第11期660-665,共6页
Human epidermal growth factor receptor 2 (HER2) is over-expressed in 20%-25% of invasive breast cancer and is associated with an aggressive tumor phenotype and reduced survival rate. As a clinically widely applied H... Human epidermal growth factor receptor 2 (HER2) is over-expressed in 20%-25% of invasive breast cancer and is associated with an aggressive tumor phenotype and reduced survival rate. As a clinically widely applied HER2-targeted monoclonal antibody, trastuzumab (Herceptin), combined with chemotherapy significantly increases the no tumor survival time of the patient. However, the majority of the cancers that initially respond to Herceptin begin to counter against the treat- ment within 1 year. This review describes several important well-known trastuzumab resistance mechanisms as well as the updated advancement in this field. The sufficiently investigated mechanisms are over-activation of PI3K/AKT pathway, activa- tion of PI3K/AKT via alternative pathway, steric hindrance of receptor-antibody interaction, increase of serum HER2 extracel- lular domain, and abnormal expression of epidermal growth factor receptor (EGFR) family and their ligands. And the newly investigated mechanisms involve Darpp-32 and t-Darpp, autophagy of tumor cells, HSP27, HsP90, c-MYC, ADAM proteases, EphA2, Racl, MUCI*, HER2△16, and mesenchymal CD44(pos)CD24(neg/low) phenotype. 展开更多
关键词 human epidermal growth factor receptor 2 (HER2) TRASTUZUMAB resistance PI3K/AKT IGF-1R MUC4 epidermal growth factor receptor (EGFR) family
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Time Dependent Gaussian Equivalent Linearization of Duffing Oscillator Using Continuous Wavelet Transform
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作者 Arunasis Chakraborty Prateek Mittal Sabarethinam Kameshwar 《Journal of Civil Engineering and Architecture》 2013年第8期1006-1017,共12页
Evolutionary response analysis of Duffing oscillator using Gaussian equivalent linearization in wavelet based time-frequency frame work is presented here. Cubic (i.e., odd type) non-linearity associated with stiffne... Evolutionary response analysis of Duffing oscillator using Gaussian equivalent linearization in wavelet based time-frequency frame work is presented here. Cubic (i.e., odd type) non-linearity associated with stiffness and damping is modeled. The goal of this research is to develop the mathematical model of an equivalent linear system which is applicable for different non-stationary input processes (i.e., either summation of amplitude modulated stationary orthogonal processes or digitally simulated non-stationary processes). The instantaneous parameters of the ELTVS (equivalent linear time varying system) are evaluated by minimizing the error between the displacements of non-linear and equivalent linear systems in wavelet domain. For this purpose, three different basis functions (i.e., Mexican Hat, Morlet and a modified form of Littlewood-Paley) are used. The unknown parameters (i.e., natural frequency and damping) of the ELTVS are optimized in stochastic least square sense. Numerical results are presented for different types of input to show the applicability and accuracy of the proposed wavelet based linearization technique. 展开更多
关键词 Statistical linearization wavelet analysis Duffing oscillator evolutionary process.
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Determination of Trihalomethanes in Water Samples Using Headspace Solid-Phase Microextraction Gas Chromatography
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作者 Nitaya Saesim Wanna Kanchanamayoon 《Journal of Chemistry and Chemical Engineering》 2010年第6期1-7,共7页
The chlorination process is one of the water treatment method used for the disinfection of water. The disinfection by products are trihalomethanes such as chloroform, dichloromethane, dibromochloromethane and bromofor... The chlorination process is one of the water treatment method used for the disinfection of water. The disinfection by products are trihalomethanes such as chloroform, dichloromethane, dibromochloromethane and bromoform. A headspace solid-phase microextraction method has been developed for determination oftrihalomethanes in water samples. The experimental parameters such as the stirring rate, extraction time, extraction temperature and desorption time were investigated. The linearity, detection limits and percentage recovery were evaluated. The optimum conditions were stirring rate 800 rpm/min, extraction time 6 min, extraction temperature 20 ~C, desorption time 2.5 min and desorption temperature 220 ~C. The detection limits were 0.01 ~g/L and the recoveries were in the range of 86-110 %, The proposed method was successfully applied to determination of THM4 in tap water samples. The THM4 contents were varied depending on the sample sites and the season. The total THM4 contents in cool, summer and rainy season were in the range of 27.58-41.89, 32.06-60.73 and 46.26-69.87 p.g/L, respectively. Confirmation of the detected compounds in water samples were performed by gas chromatograph-mass spectrometer. The mass spectra of the target compounds in water samples is in good agreement with trihalomethanes standard spectra. 展开更多
关键词 Water analysis gas chromatography TRIHALOMETHANES disinfection by product solid-phase microextraction.
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Influence of Conditions on Reuterin Accumulation by the Resting Cell Biotransformation Process
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作者 陈国 杨道茂 +1 位作者 肖雅琴 陈宏文 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第6期1023-1027,共5页
3-Hydroxypropionaldehyde (3-HPA) is a potential valuable chemical and new broad-spectrum antim-icrobial substance. In order to improve the conversion of 3-HPA/glycerol, our work studied the two-step process from gly... 3-Hydroxypropionaldehyde (3-HPA) is a potential valuable chemical and new broad-spectrum antim-icrobial substance. In order to improve the conversion of 3-HPA/glycerol, our work studied the two-step process from glycerol to 3-HPA, and investigated the influence of cell harvest time, glycerol concentration, biomass con-centration, pH and temperature on the production of 3-HPA by Lactobacillus reuteri CG001, respectively. The re-sults showed that molar conversion yield of 3-HPA/glycerol reached 97.9% under the condition that 200 mmol·L-1 glycerol was converted by 25.3 g·L-1 resting cell for 1 h at 30 ℃. The cells could not be reused directly because the L. reuteri almost lost its bioconversion activity completely, but the ability of glycerol conversion could gradually recover if the fresh medium was added to the deactivated cell for 4 h. 展开更多
关键词 Lactobacillus reuteri 3-HYDROXYPROPIONALDEHYDE REUTERIN bioconversion
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Process Engineering Considerations of Electrochemical Storage
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作者 Wolfgang Georg Winkler 《Journal of Energy and Power Engineering》 2014年第10期1763-1776,共14页
Thermodynamically, electric storages can be generally characterized as a type of regenerative machines able to operate in a work and a power machine mode. A consideration of the concentration term of the Nernst equati... Thermodynamically, electric storages can be generally characterized as a type of regenerative machines able to operate in a work and a power machine mode. A consideration of the concentration term of the Nernst equation already shows a first principal difference between batch and flow processes, because the reaction coordinate depends on time for batch processes and on the flow coordinate for flow processes. Ionic substances may be stored within a volume surrounding the electrodes or on the surface of the electrodes itself. The volume concentrations of the reactants are thus a determining parameter of electrochemical storage beside voltage and the ratio of released electrons per reacting reference substance. Surface storage allows only batch processes while volume storage allows batch and flow processes. This characterization identifies the benefits of certain reactions regarding mass and volume related energy density in a simple way at a very early stage of development. It also allows a simple calculation of possible discharging times. 展开更多
关键词 Process analysis thermodynamic analysis storage principles BATTERIES fuel cells.
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Flexible gel(FG) for gas-drainage drilling sealing material based on orthogonal design
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作者 Zhai Cheng Xu Jizhao +1 位作者 Xiang Xianwei Zhong Chao 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第6期1031-1036,共6页
Aiming to resolve the technical problems of lower gas concentrations and a reduced effective drainage period caused by gas-drainage borehole fracture development, a flexible gel (FG) gas-drainage borehole sealing ma... Aiming to resolve the technical problems of lower gas concentrations and a reduced effective drainage period caused by gas-drainage borehole fracture development, a flexible gel (FG) gas-drainage borehole sealing material was developed that adapts to borehole deformation. In this study, based on orthogonal tests, the effect of the ratio of material to water, stirring time and stirring speed on the viscosity, filtration property, water retention and pumpability of the FG were studied. The results indicate that the stirring speed, ratio of material to water and stirring time in turn increased the viscosity and the ratio of material to water, stirring time and stirring speed enhanced the filtration property and water retention. The FG pumps smoothly and achieves the optimal state of high water retention, low fluid loss and low viscosity when the ratio of material to water is 1:10, the stirring speed is 800 r/min, and the stirring time is 12 min. The field test results indicate that, after using the FG, the average drainage gas concentration increases by 25.9% and 27.6g and the average negative pressure of extraction increases by 2.7 kPa and 3.5 kPa com- pared with expansive cement and polyurethane, respectively. 展开更多
关键词 Gas drainageFlexible gelOrthogonal designLiquidityFiltration propertyWater retention
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Oxidative desulfurization performance optimization of tert- amyl hydroperoxide
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作者 HUO Ning-boI Liu zhigang 《International Journal of Technology Management》 2014年第8期86-89,共4页
The desulphurization experiment of oil-soluble oxidant tert-amyl hydroperoxide with dibenzothiophene dissolved in decalin as model-oil was researched. Characterisation on oxidation product was made, and dibenzothiophe... The desulphurization experiment of oil-soluble oxidant tert-amyl hydroperoxide with dibenzothiophene dissolved in decalin as model-oil was researched. Characterisation on oxidation product was made, and dibenzothiophene removal rate was computed. The influence factors of the oxidative reaction regent amount and the condtions of reaction temperature and reaction time were optimized and compared. The best reaction condition was reaction temperature 90℃, reaction time 3 h, ratio of oxygen to sulfur 4:1, catalyst amount 0.12 g. Dibenzothiophene removal rate reached 97% in this reaction condition. 展开更多
关键词 tert-amyl hydroperoxide DIBENZOTHIOPHENE removal rate
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Effect of Storage Time and Temperature on Phenolic, Flavonoid Contents and Antioxidant Properties of Milled Rice
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作者 Pimpaporn Thanajiruschaya Wathinee Doksaku +1 位作者 Phanee Rattanachaisit Jirasak Kongkiattikajorn 《Journal of Life Sciences》 2011年第6期447-453,共7页
The objective of this study was to determine the phenolic, flavonoid contents and amioxidant properties in the milled rice cv. Khaw Dawk Mali 105 during storage for 0-7 months at different temperatures. The total phen... The objective of this study was to determine the phenolic, flavonoid contents and amioxidant properties in the milled rice cv. Khaw Dawk Mali 105 during storage for 0-7 months at different temperatures. The total phenolic content of non-stored rice was 17.02 mg/g and 7-month stored rice at 25℃ was 6.07 + 0.01 mg/g while storage for 7 months at 37 ℃, the phenolic contents was 7.29±0.35 mg/g. The total flavonoid content of non-stored rice was 13.26 ± 0.01 mg/g and 7 month stored rice at 25 ℃ was 6.74±0.01 mg/g while storage for 7 months at 37℃, the flavonoid content was 6.45 ± 0.12 mg/g. The antioxidant property determined by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical expressed in the value of EC50 (DPPH) of non-stored rice was 0.27 mg/mL and 7-month stored rice at 25℃ was 12.15 mg/mL while storage for 7 months at 37℃, the antioxidant property was 6.34 mg/mL. The antioxidant property determined by lipid peroxidation expressed in the value of EC50 (lipid peroxidation) of non-stored rice was 0.12 mg/mL and 7 month stored rice at 25℃ was 1.18 rag/mL while storage for 7-months at 37 ℃, the antioxidant property was 1.10 mg/mL. The results showed that storage time at 25℃ and 37 ℃ caused decrease of extractable phenolic and flavonoid contents and antioxidant activities of the milled rice however 7-month stored milled rice at 37 ℃ milled rice at 25 ℃. 展开更多
关键词 ANTIOXIDANT PHENOLIC flavonoid RICE storage.
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