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福州人饮食性味凉热和温度高低与体质关系研究 被引量:27
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作者 郑承铎 郑立升 +1 位作者 杨晓云 张萍 《中国中医基础医学杂志》 CAS CSCD 2002年第2期58-61,共4页
目的 :探讨饮食性味凉热和温度高低对人体影响的规律性与体质的关系。方法 :通过对 2 2 4例的问卷调查 ,了解福州人对饮食性味凉热和 /或温度高低的不同反应 ,用统计学方法探讨其中的相关性和规律性。结果 :①女性恶热性饮食的发生率高... 目的 :探讨饮食性味凉热和温度高低对人体影响的规律性与体质的关系。方法 :通过对 2 2 4例的问卷调查 ,了解福州人对饮食性味凉热和 /或温度高低的不同反应 ,用统计学方法探讨其中的相关性和规律性。结果 :①女性恶热性饮食的发生率高于男性 ,其余与性别无关 ;②年龄与恶低温饮食、恶凉性饮食及喜较烫饮食的发生率之间呈显著中度正相关 ;③既往慢性病或症的发生率与恶低温饮食、恶凉性饮食、喜较烫饮食及恶热性饮食的发生率之间呈高度正相关 ;④低温饮食和寒凉性质饮食引发不同系统症状的发生率之间呈高度正相关 ,主要诱发胃肠不适和咳喘 ;⑤热性饮食所引发的症状与中医对“火热”症状的表述相符 ;⑥恶低温饮食、恶凉性饮食、喜较烫饮食及恶热性饮食等不同体质状态 ,在同一人体中重叠出现率大于单独出现率。结论 :饮食性味凉热和温度高低对人体的影响是客观存在的 ,且有明确的规律可循。这种规律与中医对人体现象的观察及关于寒热的理论相一致 ,可作为临床体质辨证的依据 ,进一步深入研究对中医理论及人体科学的发展都有重要意义。 展开更多
关键词 饮食性味凉热 饮食温度高低 体质 福州人 中医药学
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基于流变学的玄武岩矿物纤维改性岩沥青高低温性能研究 被引量:16
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作者 何东坡 左惠宇 《功能材料》 EI CAS CSCD 北大核心 2020年第10期10081-10088,共8页
为改善岩改性沥青低温性能不足的问题,选用玄武岩矿物纤维对其进行复合改性,改变两者不同掺量组合制备复合改性沥青,通过动态剪切流变仪(DSR)和弯曲梁流变仪(BBR)对复合改性沥青进行试验,计算得出复合改性沥青高低温连续分级温度TLH和TL... 为改善岩改性沥青低温性能不足的问题,选用玄武岩矿物纤维对其进行复合改性,改变两者不同掺量组合制备复合改性沥青,通过动态剪切流变仪(DSR)和弯曲梁流变仪(BBR)对复合改性沥青进行试验,计算得出复合改性沥青高低温连续分级温度TLH和TLC作为评价复合改性沥青高低温性能的指标。试验结果表明:沥青TLH会随岩沥青的加入而增高,TLC也随之上升;玄武岩矿物纤维的加入对沥青TLH影响不大,但TLC明显下降,有效地解决了岩沥青低温性能不足问题。根据试验得出的复合改性沥青高低温连续分级温度区间,发现在基质沥青中掺入6%(质量分数)玄武岩矿物纤维和4%(质量分数)伊朗岩沥青复合改性沥青连续分级温度区间跨度最大,高低温综合性能最佳,且通过扫描电镜测试观察发现岩沥青充分融解,纤维分散均匀。 展开更多
关键词 道路工程 玄武岩矿物纤维 岩沥青 沥青流变性能 高低温连续分级温度
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High density dislocations enhance creep ageing response and mechanical properties in 2195 alloy sheet
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作者 WEI Shuo MA Pei-pei +3 位作者 CHEN Long-hui YANG Jian-shi ZHAN Li-hua LIU Chun-hui 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2194-2209,共16页
The creep strain of conventionally treated 2195 alloy is very low,increasing the difficulty of manufacturing Al-Cu-Li alloy sheet parts by creep age forming.Therefore,finding a solution to improve the creep formabilit... The creep strain of conventionally treated 2195 alloy is very low,increasing the difficulty of manufacturing Al-Cu-Li alloy sheet parts by creep age forming.Therefore,finding a solution to improve the creep formability of Al-Cu-Li alloy is vital.A thorough comparison of the effects of cryo-deformation and ambient temperature large pre-deformation(LPD)on the creep ageing response in the 2195 alloy sheet at 160℃with different stresses has been made.The evolution of dislocations and precipitates during creep ageing of LPD alloys are revealed by X-ray diffraction and transmission electron microscopy.High-quality 2195 alloy sheet largely pre-deformed by 80%without edge-cracking is obtained by cryo-rolling at liquid nitrogen temperature,while severe edge-cracking occurs during room temperature rolling.The creep formability and strength of the 2195 alloy are both enhanced by introducing pre-existing dislocations with a density over 1.4×10^(15)m^(−2).At 160℃and 150 MPa,creep strain and creep-aged strength generally increases by 4−6 times and 30−50 MPa in the LPD sample,respectively,compared to conventional T3 alloy counterpart.The elongation of creep-aged LPD sample is low but remains relevant for application.The high-density dislocations,though existing in the form of dislocation tangles,promote the formation of refined T1 precipitates with a uniform dispersion. 展开更多
关键词 creep ageing Al-Cu-Li alloy high dislocation density cryogenic rolling dislocation strengthening
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Interpretation of 850 hPa Temperature in Temperature Forecast of Jiamusi Area 被引量:1
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作者 尹嫦姣 孙洪伟 《Agricultural Science & Technology》 CAS 2017年第4期660-664,共5页
Based on the initial field temperature data of ECMWF 850 hPa from Jan- uary 2012 to December 2015, linear interpolation method of ECMWF was employed to calculate the 850 hPa temperature values at 8:00 and 20:00 of 7... Based on the initial field temperature data of ECMWF 850 hPa from Jan- uary 2012 to December 2015, linear interpolation method of ECMWF was employed to calculate the 850 hPa temperature values at 8:00 and 20:00 of 7 stations (Jiamusi, Tangyuan, Huachuan, Huanan, Fujin, Tongjiang, Fuyuan). Combined with the observed daily minimum and maximum air temperatures at the same time of the 7 stations, the correlations of the 850 hPa temperature values at 8:00 and 20:00 with the daily maximum or minimum air temperature of the ground meteorological obser- vation stations were established, and the ground observation data in accordance with the relevant analysis and correlation test principle of the prediction equation for factor were primarily selected. Regression method was used to establish forecast e- quation dividing into counties, month by month. The results showed that the 850 hPa temperature values at 8:00 and 20:00 were significantly correlated with the daily maximum or minimum air temperature, and the established temperature fore- cast equation was of certain guiding significance for the forecast of daily minimum and maximum temperature, which could help to improve the forecast accuracy. 展开更多
关键词 850 hPa temperature Daily air temperature Regression equation Cor- relation
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也探鸡蛋在稀盐酸溶液中的沉浮问题
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作者 党文祥 《中学教学参考》 2021年第26期76-79,共4页
鸡蛋在稀盐酸溶液中的沉浮,是一种很有趣的实验现象。鸡蛋的沉浮过程涉及两个重要参数:鸡蛋沉底的时间长短;鸡蛋自动下沉的次数多少。通过对比性实验探究和分析归纳得出:鸡蛋沉浮与盐酸浓度和温度有关。(1)温度相同,浓度较大时,鸡蛋沉... 鸡蛋在稀盐酸溶液中的沉浮,是一种很有趣的实验现象。鸡蛋的沉浮过程涉及两个重要参数:鸡蛋沉底的时间长短;鸡蛋自动下沉的次数多少。通过对比性实验探究和分析归纳得出:鸡蛋沉浮与盐酸浓度和温度有关。(1)温度相同,浓度较大时,鸡蛋沉底的时间较短,自动下沉的次数较少。(2)浓度相同,温度较高时,鸡蛋沉底的时间较短,自动下沉的次数较少。鸡蛋沉浮的本质是由密度决定的。当鸡蛋与溶液的密度大小出现交替变化时,就会发生自动沉浮现象。文章大致确定了与温度相对应的浓度参考值,举例说明了参考值在实际应用中的灵活处理方法,使鸡蛋的沉浮实验得到了推广。 展开更多
关键词 鸡蛋沉浮 密度关系 浓度大小 温度高低
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A successful mountain rescue operation in Yushu Earthquake 被引量:15
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作者 Wu Tianyi Li Suzhi +1 位作者 Hou Shike Ouzhu Luobu 《Engineering Sciences》 EI 2012年第1期2-7,共6页
On April 14, 2010, an earthquake reaching 7.1 Richter scale struck Jiegu Town of Yushu. More than 2 698 people were confirmed dead, and 12 135 were injured, of which 1 434 were severely injured. Rescue operation was c... On April 14, 2010, an earthquake reaching 7.1 Richter scale struck Jiegu Town of Yushu. More than 2 698 people were confirmed dead, and 12 135 were injured, of which 1 434 were severely injured. Rescue operation was carried out soon after the disaster; however, the rescue teams face great challenges of altitude hypoxia, freezing temperature and very bad weather. Thus, 1 434 severe injuries were rapidly transported airlifted to hospitals in Xining and neighboring provinces for effective treatment. The extremity trauma (49.9 % ) was the most common patteru of injuries. Asphyxia (40.8 % ) was by far the most important reason for death. A high incidence of acute altitude illness in the lowland rescuers was a special medical problem during the highest earthquake in Yushu. We have learned more lessons from Yushu Earthquake. 展开更多
关键词 Yushu Earthquake mountain rescue medical emergency acute altitude illness
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Observed trends in diurnal temperature range over Nigeria 被引量:1
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作者 DIKE Victor Nnamdi LIN Zhaohui +1 位作者 WANG Yuxi NNAMCHI Hyacinth 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第2期131-139,共9页
The long-term trend of diurnal temperature range(DTR)over Nigeria was examined using daily station-based datasets for the period 1971–2013.The results show that the regionally averaged DTR has decreased significantly... The long-term trend of diurnal temperature range(DTR)over Nigeria was examined using daily station-based datasets for the period 1971–2013.The results show that the regionally averaged DTR has decreased significantly(-0.34°C per decade)over the Nigerian Sahel(north of 10°N),but there has been a slight increasing trend(0.01°C per decade)over the Nigerian Guinea Coast.The annual decreasing trend of DTR in the Nigerian Sahel is mainly attributable to the significant increasing trend in daily minimum temperature(Tmin,0.51°C per decade),which far outstrips the rate of increase in the daily maximum(Tmax,0.17°C per decade).In contrast,the comparable trends in Tmin(0.19°C per decade)and Tmax(0.20°C per decade)may explain the non-significant trend of the DTR averaged over the Guinea Coast region.It is observed that the DTR has decreased more in boreal summer(June–July–August)than in boreal winter(December–January–February)for the regions.Furthermore,it is found that the significant DTR declining trend over the Nigerian Sahel is closely associated with an increasing trend of annual and summer precipitation in the region,but the increasing DTR trend in the Nigerian Guinea Coast region can be attributed to the decreasing trend of cloud cover over the region. 展开更多
关键词 Diurnal temperature range maximum/minimum temperature TREND NIGERIA
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Metabolism of polychaete Neanthes japonica Izuka: relations to temperature,salinity and body weight 被引量:3
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作者 刘勇 线薇薇 孙世春 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第2期356-364,共9页
Polychaete Neanthes japonica is a species geographically specific in China and Japan with important scientific implication and commercial value. In this study, the relations of body weight, salinity and temperature to... Polychaete Neanthes japonica is a species geographically specific in China and Japan with important scientific implication and commercial value. In this study, the relations of body weight, salinity and temperature to oxygen consumption and ammonia excretion of N. japonica were determined. Three different groups in body weight (large: 2.34±0.36 g, middle: 1.50±0.21 g and small: 0.62±0.12 g) were set for all experiments. Results show that the body weight is negatively related to the rates of oxygen consumption and ammonia excretion; and the relationship is significant. The oxygen consumption and ammonia excretion at 24℃ decreased at salinity from 5 to 30 and increased above 30, indicating that both lower and higher salinity are adverse and certain degree of salinity stress is necessary for enhancing the energy demand. At salinity 30, rising temperature from 18℃ to 30℃, the oxygen consumption increased before 27℃ and then decreased. However, the relation of ammonia excretion and temperature seems more complex. Two-way ANOVA shows that salinity, temperature and body weight all have a significant effect on the oxygen consumption and ammonia excretion of the worm. Moreover, interaction between salinity/temperature and body weight is also significant. O:N (oxygen/nitrogen) ratio varies greatly in this case from 5.97 to 463.22, indicating that N. japonica can regulate the type of metabolic substrate against environment changes. 展开更多
关键词 Neanthes japonica SALINITY TEMPERATURE body weight ammonia excretion Oxygen consumption
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Microstructure and isothermal oxidation of 3Al_2O_3·2SiO_2/SiC coating on high and low density carbon-carbon composites 被引量:1
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作者 L.GBOLOGAH 熊翔 +2 位作者 郝安林 曾毅 张武装 《Journal of Central South University》 SCIE EI CAS 2013年第1期30-36,共7页
Carbon-carbon composite (C/C) materials are prone to severe oxidation and volatilization problems. To address these issues, mullite (3Al2O3.2SiO2)/silicon carbide (SIC) coatings were deposited on C/C composite s... Carbon-carbon composite (C/C) materials are prone to severe oxidation and volatilization problems. To address these issues, mullite (3Al2O3.2SiO2)/silicon carbide (SIC) coatings were deposited on C/C composite substrates characterized into high and low densities. The coatings were applied by a two-step approach: pack cementation and silica sol based slurry coating processes. The relationship between the microstructure of 3Al2O3·2SiO2/SiC coatings and C/C substrates during isothermal oxidation cycle at 1 500 ℃ was investigated using X-ray diffractometer (XRD) and scanning electron microscope (SEM) mounted with energy dispersive spectrometer (EDS). The results indicate that the density of the substrates has a marked effect on the coatings. Dense, thick and well-bonded coatings are obtained in the high density substrate. After 106 h of isothermal oxidation, the high density substrate with 3Al2O3-2SiO2/SiC coating offers effective protection as compared to low density substrate suffering recession. 展开更多
关键词 MULLITE carbon-carbon composite slurry coating isothermal oxidation
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环境应力筛选(ESS)在电子装备中的应用
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作者 李浙军 《通信对抗》 2003年第1期48-57,共10页
本文介绍了ESS的目的、作用、基本特性及印制板组件级以上的电子产品在ESS中的实际应用,以及ESS的最新发展动态.
关键词 环境应力筛选 ESS 质量控制检查 随机振动 高低温度循环 产品可靠性 电子装备
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Wall Sticking of High Water-Cut, Highly Viscous and High Gel-Point Crude Oil Transported at Low Temperatures 被引量:18
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作者 Zheng Haimin Huang Qiyu +1 位作者 Wang Changhui Wang Xi 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第4期20-29,共10页
Some crude oils with high water cut have the capability to flow below the oil gel point, while the oil particles adhere to the pipe wall in the form of paste, also called "wall sticking". Wall sticking is a ... Some crude oils with high water cut have the capability to flow below the oil gel point, while the oil particles adhere to the pipe wall in the form of paste, also called "wall sticking". Wall sticking is a serious problem during the pipeline transportation, leading to partial or total blockage of the pipeline and energy wastage. In this paper, a series of laboratory flow loop experiments were conducted to observe the wall sticking characteristics of crude oil with high water cut, high viscosity and high gel point at low transportation temperatures. The effects of shear stress and water cut on the wall sticking rate and occurrence temperature were investigated. Experimental results indicated that the wall sticking rate and occurrence temperature were lower under stronger shear stress and higher water cut conditions. A criterion of wall sticking occurrence temperature(WSOT) and a regression model of wall sticking rate were then established. Finally, the software was developed to calculate the pressure drop along the pipelines of crude oils with high water-cut. It was able to predict the wall sticking thickness of gelled oil and then calculate the pressure drop along the pipelines. A typical case study indicated that the prediction results obtained from the software were in agreement with actual measured values. 展开更多
关键词 wall sticking high viscosity high water cut flow loop regression model
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Thin Film Chip Resistors with High Resistance and Low Temperature Coefficient of Resistance 被引量:5
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作者 王秀宇 张之圣 +1 位作者 白天 刘仲娥 《Transactions of Tianjin University》 EI CAS 2010年第5期348-353,共6页
High resistance thin film chip resistors(0603 type) were studied,and the specifications are as follows:1 k? with tolerance about ±0.1% after laser trimming and temperature coefficient of resistance(TCR) less than... High resistance thin film chip resistors(0603 type) were studied,and the specifications are as follows:1 k? with tolerance about ±0.1% after laser trimming and temperature coefficient of resistance(TCR) less than ±15×10-6/℃.Cr-Si-Ta-Al films were prepared with Ar flow rate and sputtering power fixed at 20 standard-state cubic centimeter per minute(sccm) and 100 W,respectively.The experiment shows that the electrical properties of Cr-SiTa-Al deposition films can meet the specification requirements of 0603 ty... 展开更多
关键词 thin film chip resistor high resistance low temperature coefficient of resistance alloy target magnetic sputtering Cr-Si-Ta-Al film
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Characteristics and Changes of Cold Surge Events over China during 1960-2007 被引量:13
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作者 DING Ting QIAN Wei-Hong YAN Zhong-Wei 《Atmospheric and Oceanic Science Letters》 2009年第6期339-344,共6页
This paper demonstrates regional characteristics, a long-term decreasing trend, and decadal variations in the frequency of cold surge events based on daily mean temperature and daily minimum temperature data in China&... This paper demonstrates regional characteristics, a long-term decreasing trend, and decadal variations in the frequency of cold surge events based on daily mean temperature and daily minimum temperature data in China's Mainland from 1960 to 2008. During these 48 years four high frequency centers of cold surge events were located in Xinjiang, central North China, northeast China, and southeast China. A main frequency peak of cold surge events occurs in autumn for the four regions and another peak is detected in spring over northeast China and southeast China. The regional pattern of cold surge frequencies is in accordance with the perturbation kinetic energy distribution in October December, January, and February April. The long-term decreasing trend ( 0.2 times/decade) of cold surge frequencies in northeast China and decadal variations in China are related to the variations of the temperature difference between southern and northern China in the winter monsoon season; these variations are due to the significant rising of winter temperatures in high latitudes. 展开更多
关键词 cold surge extreme event TEMPERATURE climate change TREND
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Influence of CaO-based expansive agent,superabsorbent polymers and curing temperature on pore structure evolution of early-age cement paste
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作者 ZHAO Hai-tao LI Xiao-long +5 位作者 XIE Dong-sheng DI Yun-fei HUANG Jie XU Wen WANG Peng-gang ZUO Jun-qing 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第5期1663-1673,共11页
Cracks easily generate in concrete at early age owing to the shrinkage deformation.CaO-based expansion agent(CEA)and superabsorbent polymers(SAP)have been extensively used for the mitigation of concrete shrinkage.The ... Cracks easily generate in concrete at early age owing to the shrinkage deformation.CaO-based expansion agent(CEA)and superabsorbent polymers(SAP)have been extensively used for the mitigation of concrete shrinkage.The macroscopic properties of concrete are highly determined by the microstructure.In this study,the influence of CEA and SAP addition on the pore structure evolution of cement paste under different curing temperatures was evaluated via low-field nuclear magnetic resonance spectroscopy.Test results indicated that,in cement paste,a higher CEA content led to a higher porosity and a larger most probable pore diameter(MPPD).Meanwhile,SAP addition increased the porosity and MPPD of CEA cement paste at early age but decreased them after 7 d,and a higher SAP content always brought a higher porosity and MPPD.Furthermore,the addition of SAP led to a lower porosity and MPPD of CEA cement paste than that of plain cement paste after 14 d.Moreover,the porosity and MPPD of CEA cement paste decreased first and subsequently increased as the curing temperature raised. 展开更多
关键词 cement paste pore structure CaO-based expansion agent superabsorbent polymers curing temperature low-field nuclear magnetic
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High-temperature treatment induced carbon anode with ultrahigh Na storage capacity at low-voltage plateau 被引量:8
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作者 Chenglong Zhao Qidi Wang +3 位作者 Yaxiang Lu Baohua Li Liquan Chen Yong-Sheng Hu 《Science Bulletin》 SCIE EI CSCD 2018年第17期1125-1129,共5页
Sodium-ion batteries (NIBs) show great prospect on the energy storage applications benefiting from thei low cost and the abundant Na resources despite the expected lower energy density compared wit lithium-ion batte... Sodium-ion batteries (NIBs) show great prospect on the energy storage applications benefiting from thei low cost and the abundant Na resources despite the expected lower energy density compared wit lithium-ion batteries (LIBs). To further enhance the competitive advantage, especially in energy densit3 developing the high-capacity carbon anode materials can be one of the effective approaches to realiz this goal. Herein, we report a novel carbon anode made from charcoal with a high capacity of ~400 Ah g i, wherein about 85% (〉330 mAh g^-1) of its total capacity is derived from the long plateau regio below ~0.1 V. which differs fiom those of typical hard carbon materials (~300 mAh g^-l) in NIBs but i similar to the graphite anode in LIBs. When coupled with air-stable Nao.gCuo.22Feo.3oMno.4802 oxid cathode, a high-energy density of ~240 Wh kg^-1 is achieved with good rate capability and cyclin stability. The discovery of this promising carbon anode is expected to further improve the energy densit of NIBs towards large-scale electrical energy storage. 展开更多
关键词 Sodium-ion battery Na storage Hard carbon Charcoal High-temperature carbonization Low-voltage plateau
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Air-promoted selective hydrogenation of phenol to cyclohexanone at low temperature over Pd-based nanocatalysts 被引量:2
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作者 Qing Guo Shiguang Mo +6 位作者 Pengxin Liu Weidong Zheng Ruixuan Qin Chaofa Xu Youyunqi Wu Binghui Wu Nanfeng Zheng 《Science China Chemistry》 SCIE EI CAS CSCD 2017年第11期1444-1449,共6页
Attaining high activity with high selectivity at low temperature is challenging in the selective hydrogenation of phenol to cyclohexanone due to its high activation energy (Ea, 55-70 kJ/mol). Here we report a simple... Attaining high activity with high selectivity at low temperature is challenging in the selective hydrogenation of phenol to cyclohexanone due to its high activation energy (Ea, 55-70 kJ/mol). Here we report a simple and efficient strategy for phenol hydrogenation catalyzed by Pd in aqueous phase at 30 ℃ by introducing air to promote the catalysis. With the assistance of air, 〉99% conversion and 〉99% selectivity were achieved over Pd(111)/Al2O3 with an overall turnover frequency (TOF) of 621 h-1, -80 times greater than that of the state-of-art Pd catalyst at 30 ℃. Mechanism studies revealed that phenol was activated to generate phenoxyl radicals. The radicals were yielded from the reaction between phenol and hydroxyl radicals in the presence of hydrogen, oxygen and protic solvent on Pd. The phenoxyl pathway resulted in a low apparent Ea (8.2 kJ/mol) and thus high activity. More importantly, this strategy of activating substrate by air can be adapted to other Pd based catalysts, offering a new thinking for the rational design of cyclohexanone production in industry. 展开更多
关键词 selective hydrogenation PHENOL PALLADIUM NANOCATALYSIS RADICAL
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Interaction between temperature and photoperiod in regulation of flowering time in rice 被引量:6
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作者 SONG YuanLi GAO ZhiChao LUAN WeiJiang 《Science China(Life Sciences)》 SCIE CAS 2012年第3期241-249,共9页
Photoperiod and temperature are two pivotal regulatory factors of plant flowering. The floral transition of plants depends on accurate measurement of changes in photoperiod and temperature. The flowering time of rice ... Photoperiod and temperature are two pivotal regulatory factors of plant flowering. The floral transition of plants depends on accurate measurement of changes in photoperiod and temperature. The flowering time of rice (Oryza sativa) as a facultative short-day (SD) plant is delayed under long-day (LD) and/or low temperature conditions. To elucidate the regulatory functions of photoperiod and temperature on flowering time in rice, we systematically analyzed the expression and regulation of several key genes (Hd3a, RFT1, Ehdl, Ghd7, RID1/Ehd2/OsIdl, Se5) involved in the photoperiodic flowering regulatory pathway under different temperature and photoperiod treatments using a photoperiod-insensitive mutant and wild type plants. Our re- sults indicate that the Ehdl-Hd3a/RFT1 pathway is common to and conserved in both the photoperiodic and temperature flow- ering regulatory pathways. Expression of Ehdl, Hd3a and RFT1 is dramatically reduced at low temperature (23~C), suggesting that suppression of Ehdl, Hd3a and RFT1 transcription is an essential cause of delayed flowering under low temperature con- dition. Under LD condition, Ghd7 mRNA levels are promoted at low temperature (23~C) compared with normal temperature condition (28℃), suggesting low temperature and LD treatment have a synergistic role in the expression of Ghd7. Therefore, upregulation of Ghd7 might be a crucial cause of delayed flowering under low temperature condition. We also analyzed Hdl regulatory relationships in the photoperiodic flowering pathway, and found that Hdl can negatively regulate Ehdl transcription under LD condition. In addition, Hdl can also positively regulate Ghd7 transcription under LD condition, suggesting that the heading-date of rice under LD condition is also regulated by the Hdl-Ghd7-Ehdl-RFT1 pathway. 展开更多
关键词 RICE PHOTOPERIOD TEMPERATURE flowering regulation INTERACTION
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Lattice instability of V_2AlC at high pressure
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作者 YANG ZeJin LIU Qiang +5 位作者 LI Jin WANG Zhao GUO AiMin LINGHU RongFeng CHENG XinLu YANG XiangDong 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第5期916-924,共9页
We investigate the elastic and thermodynamic properties of nanolaminate VzA1C by using the ab initio pseudopotential total energy method. The axial compressibility shows that the c axis is always stiffer than a axis. ... We investigate the elastic and thermodynamic properties of nanolaminate VzA1C by using the ab initio pseudopotential total energy method. The axial compressibility shows that the c axis is always stiffer than a axis. The elastic constants revealed the structural instability at about 500 and 732 GPa. Furthermore, elastic constants C44 reached its maximum at about 550 GPa, dif- fering with the other four C^1, G2, C13 and 6"33 constants. The Poisson's ratio investigations demonstrated that a higher ionic or weaker covalent contribution in intra-atomic bonding and the degree of ionicity increases with pressure. The G/B and B]C44 investigations revealed that VzAIC is brittle and the brittleness decreases with pressure. Also, we found that V2A1C is elastic anisotropic materials and the degree of anisotropy rapidly rises with pressure. Study on Debye temperature and Grtineisen pa- rameter observed weak temperature and strong pressure responses, whereas the sensitive dependence in the thermal expansion coefficient and Helmholtz free energy are clearly seen. 展开更多
关键词 ELASTICITY thermodynamicity first principles
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Diffusion process for efficiency improvement with high sheet resistance on traditional production lines of solar cell
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作者 JIA HeShun LUO Lei +3 位作者 JIANG YanSen XU ZhenHua REN XianKun ZHANG ChunYan 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第5期962-967,共6页
By optimizing the diffusion temperature and time,four groups of samples with different sheet resistances are achieved.The front screen printing pattern and firing temperature are fine-tuned according to the needs.The ... By optimizing the diffusion temperature and time,four groups of samples with different sheet resistances are achieved.The front screen printing pattern and firing temperature are fine-tuned according to the needs.The performance of the low-and-plateau-temperature doping recipe(as recipe A)is better than that of the low-and-multiple-temperature doping recipe(as recipe B).And the 19.24%efficiency of volume production of monocrystalline solar cells with 238.95 mm2 and 80?/sq sheet resistance is obtained in the traditional process line.0.48%more efficiency is achieved than 60?/sq due to the reduction of the phosphorus surface doping and shallow junction by the low-and-plateau-temperature diffusion recipe.The module test shows that by using two drive-in zones,not only do we have a higher efficiency,but also have a stabler and lower power loss in encapsulation manufacture.It is showed that power of a large improvement will be gotten by statistical analysis and PC1D simulation. 展开更多
关键词 SOLAR EFFICIENCY SIMULATION power loss
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