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Field identification of morphological and physiological traits in two special mutants with strong tolerance and high sensitivity to drought stress in upland rice(Oryza sativa L.)

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Journal of Integrative Agriculture 2019年第5期18卷 970-981页

作者： huaNG Min XU Yu-hui wang hua-qi College of Agronomy and Biotechnology China Agricultural University

The two mutants idr1-1 and 297-28, which were obtained from the radiation mutation of HD297 and IAPAR9, were used as experimental materials in this study for a 2-year(2012 and 2013) experiment about field drought resistance identification in Beijing, China. Key agronomic traits and water-related physiological indexes were observed and measured, including the leaf anti-dead level(LADL), days to heading, plant height, setting percentage, aboveground biomass, leaf water potential(LWP), net photosynthetic rate(Pn) and transpiration rate. The results showed that the mutant idr1-1 that was under drought stress(DS) conditions for 2 years had the highest LADL grades(1.3 and 2.0) among all the materials, and they were 2–3 grades stronger than the wild-type IAPAR9 with an average that was 21.4% higher for the setting percentage than the wild type. Compared with the IAPAR9 for the 2-year average delay in the days to heading and the reduction rates in the plant height, setting percentage, and aboveground biomass under DS compared with the well-watered(WW) treatment, idr1-1 showed 3.2% less delay and 19.1, 16.4, and 6.1% less reduction, respectively. The idr1-1 in the LWP always exhibited the highest performance among all the materials. The Pn of idr1-1 under severe and mild DS comparing with that under WW was slightly decreased and even slightly increased, respectively, leading to an average reduction rate of only 0.92%, which was 26.93% less than that of IAPAR9. Under the severe DS, idr1-1 still showed the highest value of 16.88 μmol CO2 m–2 s–1 among all the materials and was significantly higher than that of IAPAR9(11.66 μmol CO2 m–2 s–1). Furthermore, only idr1-1 had the increased and the highest transpiration rate values(7.6 and 6.04 mmol H2 O m–2 s–1) under both mild and severe DS compared with the values under WW, when the transpiration rate of all the other materials significantly decreased. By contrast, the 297-28 in terms of the LADL grade under DS was the lowest(7.0)

关键词： rice mutants morphological and physiological traits drought resistance field identification

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Progress and Yield Bottleneck of Aerobic Rice in the North China Plain: A Case Study of Varieties Handao 297 and Handao 502

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Agricultural Sciences in China 2008年第6期7卷 641-646页

作者： XIE Guang-hui YU Jun wang hua-qi BAM Bouman College of Agronomy and Biotechnology China Agricultural University Beijing 100094 P.R.China Crop Soil and Water Science Division International Rice Research Institute DAPO Box 7777 Metro Manila Philippines

Aerobic rice has been considered a promising rice cultivation system as water scarcity is increasing in the world. This article summarizes the advances in aerobic rice management researches in the North China Plain, focusing on yield formation and its bottleneck. High-yielding and good-quality aerobic rice varieties adapted to aerobic soil conditions have been released officially and adopted by farmers in North China. The varieties Handao 502 and Handao 297 have been recognized as the most promising varieties reaching a yield level ranging 3.5-5.0 t ha-1 with 450-650 mm water input. Compared with lowland rice, water input in aerobic rice was more than 50% lower, and water productivity was 60% higher. Researches on responses of rice cultivars to nitrate nitrogen （N） and ammonium N supplied at early growth stages provided the first evidence for a preference of aerobic rice HD297 for nitrate N supply, compared with the lowland rice variety. Zinc uptake studies demonstrated that introduction of aerobic rice system on calcareous soils may increase zinc deficiency problems. Sink size was identified as the limitation of aerobic rice yield, because its spikelet number m-2 was too low （20000-24 000） compared with the lowland rice. For future research, more attention is suggested to be paid to yield formation focusing on effects of water regimes on tiller dynamics. Understanding of nutrient uptake and response to fertilization effects are also urgently required to establish optimized crop management technology. Additionally, alternative cropping systems based on aerobic rice should be established, and key sustainability and environmental impact issues in the systems need to be identified.

关键词： aerobic rice review water saving yield formation nitrogen zinc the North China Plain

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Effects of degradation succession of alpine wetland on soil organic carbon and total nitrogen in the Yellow River source zone,west China

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Journal of Mountain Science 2021年第3期18卷 694-705页

作者： LIN Chun-ying LI Xi-lai ZHANG Jing SUN hua-fang ZHANG Juan HAN Hui-bang wang qi-hua MA Cheng-biao LI Cheng-yi ZHANG Yu-xing MA Xue-qian State Key Laboratory of Plateau Ecology and Agriculture Qinghai UniversityXining 810016China qinghai Province Weather Modification Office Xining 810001China College of Agriculture and Animal Husbandry Qinghai UniversityXining 810016China Meteorological Institute of qinghai Province Xining 810001China qinghai Province geographic situation monitoring Institute Xining 810001China

Wetland is an important carbon pool,and the degradation of wetlands causes the loss of organic carbon and total *** study aims to explore how wetland degradation succession affects soil organic carbon(SOC)and total nitrogen(TN)contents in alpine wetland.A field survey of 180 soilsampling profiles was conducted in an alpine wetland that has been classified into three degradation succession *** SOC and TN contents of soil layers from 0 to 200 cm depth were studied,including their distribution characteristics and the relationship between *** results showed that SOC and TN of different degradation succession gradients followed the ranked order of Non Degradation(ND)>Light Degradation(LD)>Heavy Degradation(HD).SWC was positively correlated with SOC and TN(p<0.05).As the degree of degradation succession worsened,SOC and TN became more sensitive to the *** was closely related to the degree of wetland degradation succession,SWC,SOC and TN,especially in the topsoil(0-30 cm).This result showed that SWC was an important indicator of SOC/TN in alpine *** is highly recommended to strengthen water injection into the wetland as a means of effective restoration to reverse alpine meadow back to marsh alpine wetland.

关键词： Degradation succession Soil organic carbon(SOC) Total nitrogen(TN) Soil water content(SWC) Microtopography Soil depth

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Effects of low molecular weight heparin on clot rate and activated clotting time： an in vitro study

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Chinese Medical Journal 2013年第18期126卷 3553-3556页

作者： SHI Xu-bo BAI Ying LI Jie XIAO Jie wang Jian-qi ZHENG hua Cardiovascular Center Beijing Tongren Hospital Capital Medical University Beijing 100730 China

Background Due to lack of point-of-care testing, the use of low-molecular-weight heparin （LMWH） therapy in some special patients is restricted. This study was designed to explore the effects of LMWH on clot rate （CR） and activated clotting time （ACT）, and to search for an appropriate method for bedside monitoring of anticoagulant activity of LMWH. Methods Thirty-two healthy volunteers were selected from the staff of Beijing Tongren Hospital. CR and ACT were measured with different reagents （glass beads, diatomite, kaolin and magnetic bar） on blood samples spiked with increasing concentrations of LMWH （dalteparin, 0.2-1.8 IU/ml）. Correlations between concentrations of LMWH and values of CR and ACT were analysed based on the data obtained and regression analysis was performed to establish a regression equation. Results With the increase in doses of dalteparin, CR values reduced gradually. The values of CR of four reagents （glass beads, diatomite, kaolin and magnetic bar） were 20.4-4.5 IU/min, 27.4-6.9 IU/min, 27.5-7.9 IU/min and 7.8-0.1 IU/min respectively and an linear relationship was observed between the CR values and dalteparin concentrations （P〈0.05）. The values of ACT were 173-615 seconds, 130-270 seconds, 123-226 seconds, 337-1411 seconds respectively, which showed a linear regression between the ACT values and dalteparin concentrations （P〈0.01）. Differences in slope of the regression curves of ACT were observed with all the reagents tested （glass beads 248.2 s/IU, diatomite 74.8 s/IU, kaolin 58.2 s/IU and magnetic bar 1112.2 s/IU, P〈0.01）. While the minimum concentration of dalteparin was 0.2 IU/ml, 0.4 IU/ml, 1.4 IU/ml and 0.2 IU/ml separately, the ACT values of the four coagulants （glass beads, diatomite, kaolin and magnetic bar） were beyond the normal limit and showed a noticeable increase respectively （P〈0.01）. Conclusions This study showed that there was an excellent linear relationship between the CR and ACT values and dalteparin concentrations for all t

关键词： clot rate activated clotting time low molecular weight heparin

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ADDITION OF SODIUM BISULFITE TO BILIVERDIN

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Chinese Chemical Letters 1990年第2期1卷 171-172页

作者： Jin Shi MA Fang YAN Chang qi wang Jin hua CHEN Institute of Photographic Chemistry,Academia Sinica,Beijing,100101,China

Summary:Sodium bisulfite could add to the central methine bridge of biliver- din in methanol,and give sodium bilirubin-10-sulfonate,however no bilirubin was formed.

关键词： BV ADDITION OF SODIUM BISULFITE TO BILIVERDIN PP NH

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A Commented Translation of Three Short Stories from Amber Sparks’s The Unfinished World Under the Guidance of the Principle of Three Aes-thetics by XU Yuanchong

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海外英语 2020年第13期 203-204页

作者：王启华上海理工大学

Classical Chinese Poetry is known for its rich prosodies,paralleled forms and profound *** better retain po⁃ems’aesthetic appeal for its readers,Xu Yuanchong proposed and applied his“Principle of Three Aesthetics”-aesthetic of proso⁃dy,forms and ambiance-into his *** Literatures,to some extent,share the similarities with those of *** Western literatures,prosody is the musical side of language while the intertwining of sentence rhythm and metric rhythm in poetry yields strong *** translating Amber Sparks’s The Unfinished World,I found it reasonable to apply Xu’s“Principle of Three Aesthetics”into my translation due to the fact that between the lines are full of musical rhythm,paralleled structures and del⁃icate ambience cultivated by author.

关键词： Principle of Three Aesthetics Rhetoric

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碳纤维织物增强PES-C/PTFE复合材料的摩擦学性能研究

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摩擦学学报 2008年第6期28卷 551-555页

作者：赵普贾倩王齐华中国科学院兰州化学物理研究所固体润滑国家重点实验室甘肃兰州730000

利用热压成型方法制备了不同PES-C/PTFE含量的碳纤维织物增强复合材料,用LJ-500万能材料试验机和MRH-5A环块试验机分别考察了复合材料的力学性能和摩擦磨损性能,并研究了压制成型温度和等离子处理碳纤维织物对复合材料力学性能的影响.... 详细信息

利用热压成型方法制备了不同PES-C/PTFE含量的碳纤维织物增强复合材料,用LJ-500万能材料试验机和MRH-5A环块试验机分别考察了复合材料的力学性能和摩擦磨损性能,并研究了压制成型温度和等离子处理碳纤维织物对复合材料力学性能的影响.结果表明,碳纤维织物极大提高了PES-C/PTFE树脂弯曲强度,并且有效增加PES-C/PTFE树脂的耐磨性;PES-C/PTFE含量分别为42%和8%的碳纤维织物增强复合材料性力学及摩擦磨损综合性能最好.

关键词：碳纤维织物复合材料 PES-C 力学性能摩擦磨损

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