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Chinese Science Bulletin 2010年第23期55卷 2512-2516页

作者： quan NanNan bao ShaoHua YANG JianGuo Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal University Shanghai 200062 China

A highly efficient procedure has been developed for the conjugate addition of amines to electron deficient *** novel ionic liquid [HO3S-bPy][FeCl4] with both Lewis and Brφnsted acid sites has been synthesized successfully for the *** results show that the catalyst was very efficient for the conjugate addition of amines to electron deficient alkenes with excellent yields in several *** method has several key features including operational simplicity,no need of any solvent,low cost of the catalyst used,high yields,reusability,excellent chemoselectivity,and wide applicability.

关键词：共轭烯烃离子液体共轭加成催化剂电子程序胺化学选择性

Resilience and response:Unveiling the impacts of extreme droughts on forests through integrated dendrochronological and remote sensing analyses

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Forest Ecosystems 2024年第4期11卷 491-501页

作者： Han Shi Xi Peng Yong-Jiao Zhou ai-Ying Wang Xue-Kai Sun Na Li quan-Sheng bao Gude Buri Guang-You Hao CAS Key Laboratory of Forest Ecology and Silviculture Institute of Applied EcologyChinese Academy of SciencesShenyang110016China Daqinggou Ecological Research Station Institute of Applied EcologyChinese Academy of SciencesShenyang110016China University of Chinese Academy of Sciences Beijing100049China School of Life Science and Engineering Shenyang UniversityShenyang110044China Wudantala Forestry Forestry and Grassland Administration of Horqin Northeast CountyTongliao028100China

Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate ***,considerable uncertainty remains regarding the patterns in species-specific responses to extreme ***,we conducted a study integrating dendrochronology and remote sensing methods to investigate the mosaic-distributed maple-oak(native)natural forests and poplar plantations(introduced)in the Horqin Sandy Land,Northeast *** assessed the impacts of extreme droughts on tree performances by measuring interannual variations in radial growth and vegetation *** results showed that precipitation and self-calibrated palmer drought severity index(scPDSI)are the major factors influencing tree-ring width index(RWI)and normalized difference vegetation index(NDVI).The severe droughts between 2000 and 2004 resulted in reduced RWI in the three studied tree species as well as led to NDVI reductions in both the maple-oak natural forests and the poplar *** RWI reached the nadir during the2000-2004 severe droughts and remained at low levels two years after the severe drought,creating a legacy *** contrast to the lack of significant correlation between RWI and scPDSI,NDVI exhibited a significant positive correlation with scPDSI indicating the greater sensitivity of canopy performance to droughts than radial ***,interspecific differences in RWI and NDVI responses were observed,with the fast-growing poplar species experiencing a more significant RWI decrease and more negative NDVI anomaly during severe droughts than native species,highlighting the species-specific trade-offs between drought resilience and growth *** study emphasizes the importance of combining tree-level radial growth with landscape-scale canopy remote sensing to understand forest resilience and *** study improves our understanding of forest responses to extreme drought and highlights species di

关键词： Introduced tree species Native tree species NDVI Severe drought Tree-ring width

Formation of the Fertilization Pore during Oogenesis of the Fern Ceratopteris thalictroides

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Journal of Integrative Plant Biology 2010年第6期52卷 518-527页

作者： Jian-Guo Cao quan-Xi Wang Wen-Mei bao College of Life and Environment Sciences Shanghai Normal University Shanghai 200234 China

The development of the fertilization pore during oogenesis of the fern Ceratopteris thalictroides was followed using transmission electron microscopy. The newly formed egg is appressed closely to the adjacent cells. There are well-developed plasmodesmata between the egg and the ventral canal cell, but none between the egg and the jacket cells of the archegonium. During maturation, a separation cavity is formed around the egg. However, a pore region persistently connects the egg and the ventral canal cell. The extra egg membrane is formed by deposition of sheets of endoplasmic reticulum （ER）, but no ER is deposited on the inner surface of the pore region. Thus, a fertilization pore, covered by a layer of plasmalemma, is formed. The ventral canal cell undoubtedly participates the formation of the fertilization pore, probably by absorbing the sheets of ER beneath the pore region. The functional significance of the ventral canal cell in formation of the fertilization pore is discussed. The features of the mature egg include that abundant concentric membranes and osmiophilic vesicles occur in the cytoplasm of the mature egg. The initial, round nucleus of the egg eventually becomes cup-shaped. This investigation gives some new insights about the cells participating oogenesis in ferns.

关键词： Oogenesis Ferns Cells Eggs Lymphocytes

Possible Involvement of Anti-Oxidant Enzymes in the Cross-Tolerance of the Germination/Growth of Wheat Seeds to Salinity and Heat Stress

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Journal of Integrative Plant Biology 2005年第10期47卷 1211-1219页

作者： Yan-bao LEI Song-quan SONG Jia-Rui FU Xishuangbanna Tropical Botanical Garden the Chinese Academy of Sciences Yunnan 666303 China School of Life Sciences Sun Yat-Sen University Guangzhou 510275 China

The germination/growth of wheat （Triticum aestivum L. cv. Zimai 1） seeds and changes in the activities of superoxide dismutase （SOD）, ascorbate peroxidase （APX）, and catalase （CAT）, as well as in the content of thiobarbituric acid-reactive substances （TBARS）, in response to salt and heat stress, as well as cross-stress, were investigated in the present study. With increasing temperature and decreasing water potential caused by NaCI solution, the germination percentage of seeds and the fresh weight of seedlings decreased markedly, SOD activity increased, activities of APX and CAT decreased distinctly, and the TBARS content increased gradually. Seeds pretreated at 33℃ for different times displayed increased tolerance to subsequent salt stress, enhanced SOD, APX, and CAT activities, and decreased TBARS content. Seeds pretreated at -0.8 MPa NaCI for different times displayed increased tolerance to subsequent heat stress and marked increases in SOD, APX, and CAT activities, which were associated with decreased TBARS content. It is considered that the common component in the cross-tolerance of the germination and growth of wheat seeds to salinity and heat stress is the anti-oxidant enzyme system.

关键词： anti-oxidant enzymes cross tolerance germination growth heat stress salinity stress Triticum aestivum seeds.

Are the Nitro-and Amino-substituted Piperidine High-energy-density Compounds?

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Chinese Journal of Structural Chemistry 2020年第7期39卷 1266-1270页

作者： LI Bu-Tong LI Lu-Lin ZHOU quan-bao School of Chemistry and Materials Science Guizhou Education UniversityGuiyang 550018China Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of TechnologyNanchang 330013China

Nitro and amino groups were introduced into piperidine skeleton to design derivatives of piperidine(labeled asα,β1,β2,β3,γandδ).Heats of formation(HOFs)are calculated in detail at the B3PW91/6-311+G(d,p)level for these *** results show that all derivatives have negative heats of formation,which were affected by the positions of substituted *** molecular stability is estimated and analyzed based on bond dissociation energies(BDE)and characteristic heights(H50).All derivatives designed in this paper are confirmed with lower impact sensitivity than 1,3,5-trinitro-1,3,5-triazinane(RDX)and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX).Furthermore,the detonation velocities(D)and the detonation pressures(P)are predicted via the Kamlet-Jacobs *** all these molecules,δhas comparable detonation character with that of RDX and HMX and can be the candidate of high-energy-density compounds(HEDCs).

关键词： piperidine derivatives high-energy-density compounds detonation performance

Strong coupling without touching

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National Science Review 2014年第4期1卷 472-473页

作者： Ren-bao Liu quan Li Department of Physics and Centre for quantum Coherence The Chinese University of Hong Kong

If an excited atom is put in between highrelectance mirrors,the light emited by the atom can be bounced back and be re-absorbed and be re-emited,again and again until the light leaks out of the mirrors or is re-emited into a wrong *** coherent oscillation between atom and light,called vacuum Rabi oscillation,results from interference between

关键词： high Strong coupling without touching than

Intestinal endotoxemia plays a central role in development of hepatopulmonary syndrome in a cirrhotic rat model induced by multiple pathogenic factors

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World Journal of Gastroenterology 2007年第47期13卷 6385-6395页

作者： Hui-Ying Zhang De-Wu Han ai-Rong Su Li-Tong Zhang Zhong-Fu Zhao Jing-quan Ji bao-Hong Li Cheng Ji Department of Pathophysiology Changzhi Medical College Changzhi 046000 Shanxi Province China Institute of Hepatology Shanxi Medical University Taiyuan 030001 Shanxi Province China Department of Physiology Bengbu Medical College Bengbu 233030 Anhui Province China Department of Gynaecology Shanxi Modem Women Hospital Taiyuan 030012 Shanxi Province China Department of Medicine University of Southern California Los Angeles CA 90033 United States

aiM: To characterize the correlation between severity of hepatopulmonary syndrome (HPS) and degree of hepatic dysfunction,and to explore how intestinal endotoxemia (IETM) affects the development of HPS in cirrhotic rats. METHODS: Male Wister rats were fed with a diet containing maize flour,lard,cholesterol,and alcohol and injected subcutaneously with CCl4 oil solution every two days for 8 wk to induce typical cirrhosis and development of HPS. The animals were also given a nitric oxide (NO) production inhibitor,Nω-nitro-L-arginine methyl ester (L-NAME) intraperitoneally,and an iNOS inhibitor,aminoguanidine hydrochloride (AG) via gavage daily from the end of the 4th wk to the end of the 6th or 8th wk,or a HO-1 inhibitor,zinc protoporphyrin (ZnPP) intraperitoneally 12 h prior to killing. Blood,liver and lung tissues were sampled. RESULTS: Histological deterioration of the lung paralleled to that of the liver in the cirrhotic rats. The number of pulmonary capillaries was progressively increased from 6.1 ± 1.1 (count/filed) at the 4th wk to 14.5 ± 2.4 (count/filed) at the 8th wk in the cirrhotic rats. Increased pulmonary capillaries were associated with increased blood levels of lipopolysaccharide (LPS)(0.31 ± 0.08 EU/mL vs control 0.09 ± 0.03 EU/mL),alanine transferase (ALT,219.1 ± 17.4 U/L vs control 5.9 ± 2.2 U/L) and portal vein pressure. Compared with normal control animals,the number of total cells in bronchoalveolar lavage fluid (BALF) of the cirrhotic rats at the 8th wk was not changed,but the number of macrophages and the ratio of macrophages to total cells were increased by nearly 2-fold,protein expression of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) started to increase significantly at the 4th wk,and reached its peak at the 8th wk in the lung of cirrhotic rats. The increase of iNOS expression appeared to be quicker than that of eNOS. NO2-/NO3-was also increased,which was correlated to the increase of iNOS (r = 0.7699,P

关键词： Endotoxin Alcohol Nitric oxide synthase Hemeoxygenase-1 Capillary tacrophage Cirrhosis Hepatopulmonary syndrome

Pathogenesis of liver cirrhosis

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World Journal of Gastroenterology 2014年第23期20卷 7312-7324页

作者： Wen-Ce Zhou quan-bao Zhang Liang Qiao Department of General Surgery Ⅱ the First Hospital of Lanzhou University Liver Cancer Institute Zhongshan HospitalFudan University and Key Laboratory of Carcinogenesis and Cancer InvasionMinistry of Education Storr Liver Unit Westmead Millennium InstituteDepartment of Medicine and Western Clinical Schoolthe University of SydneyWestmeadNSW 2145Australia

Liver cirrhosis is the final pathological result of various chronic liver diseases,and fibrosis is the precursor of *** types of cells,cytokines and miRNAs are involved in the initiation and progression of liver fibrosis and *** of hepatic stellate cells(HSCs)is a pivotal event in *** and capillarization of liver sinusoidal endothelial cells are major contributing factors to hepatic dysfunction in liver *** Kupffer cells destroy hepatocytes and stimulate the activation of *** cycles of apoptosis and regeneration of hepatocytes contribute to pathogenesis of *** the molecular level,many cytokines are involved in mediation of signaling pathways that regulate activation of HSCs and ***,miRNAs as a post-transcriptional regulator have been found to play a key role in fibrosis and *** animal models of liver fibrosis and cirrhosis,as well as the recently identified critical cellular and molecular factors involved in the development of liver fibrosis and cirrhosis will facilitate the development of more effective therapeutic approaches for these conditions.

关键词： Cirrhosis Pathogenesis Hepatic stellate cells Cytokine miRNA Animal model Therapy

Response of vegetation to temperature and precipitation in Xinjiang during the period of 1998-2009

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Journal of Arid Land 2011年第2期3卷 94-103页

作者： XiaoMing CAO Xi CHEN AnMing bao quan WANG Key Laboratory of Oasis Ecology and Desert Environment Xinjiang Institute of Ecology and Geography CAS Urumqi 830011China Graduate University of Chinese Academy of Sciences Beijing 100039 China Faculty of Agriculture Shizuoka University Shizuoka 422-8529 Japan

In this paper,10-day spatio-temporal response of vegetation to the change of temperature and precipitation in spring,summer,autumn and whole year during the period of 1998―2009 was analyzed based on the data of SPOT VEGETATION-NDVI and 10-day average temperature or precipitation from 54 meteorological stations in *** results show that the response of 10-day NDVI to temperature was more significant than that to precipitation,and the maximal response of vegetation to temperature and precipitation lagged for two 10-day ***,the effect of temperature and precipitation on vegetation NDVI was most marked in autumn,then in spring,and it was not significant in *** response of vegetation to 10-day change of meteorological factors was positive with a long affecting duration in spring,and it had a relatively short affecting duration in autumn and ***,the 10-day maximal response of NDVI to temperature in northern Xinjiang was higher than that in southern *** correlation between the 10-day NDVI in whole year and the temperature in the 0-8th 10-day period was significantly higher than that between the annual NDVI and the annual temperature at all meteorological stations;the interannual change of NDVI was accordant well with the change of annual ***,the effect of precipitation within a year on NDVI was not *** results indicated that interannual change of temperature was not the dominant factor affecting the change of vegetation NDVI in Xinjiang,but the decrease of annual precipitation was the main factor resulting in the fluctuation of vegetation ***-day average temperature was an important factor to promote vegetation growth in Xinjiang within a year,but the effect of precipitation on vegetation growth within a year was not strong.

关键词： NDVI temperature precipitation correlation scale

Coordinated control of carbon and oxygen for ultra-low-carbon interstitial-free steel in a smelting process

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1252-1259页

作者： Min Wang Yan-ping bao quan Yang Li-hua Zhao Lu Lin State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing National Engineering Research Center of Flat Rolling Equipment University of Science and Technology Beijing

Low residual-free-oxygen before fmal de-oxidation was beneficial to improving the cleanness of ultra-low-carbon steel. For ultra-low-carbon steel production, the coordinated control of carbon and oxygen is a precondition for achieving low residual oxygen during the Ruhrstahl Heraeus （RH） decarburization process. In this work, we studied the coordinated control of carbon and oxygen for ultra-low-carbon steel during the basic oxygen furnace （BOF） endpoint and RH process using data statistics, multiple linear regressions, and thermodynamics computations. The results showed that the aluminum yield decreased linearly with increasing residual oxygen in liquid steel. When the mass ratio of free oxygen and carbon （[O]/[C]） in liquid steel before RH decarburization was maintained between 1.5 and 2.0 and the carbon range was from 0.030wt% to 0.040wt%, the residual oxygen after RH natural decarburization was low and easily controlled. To satisfy the requirement for RH decarburization, the carbon and free oxygen at the BOF endpoint should be controlled to be between 297 × 10^6 and 400 × 10^-6 and between 574 × 10^-6 and 775 × 10^-6, respectively, with a temperature of 1695 to 1715℃ and a furnace campaign of 1000 to 5000 heats.

关键词： low carbon steel smelting decarburization cleanness