检索结果-南通市图书馆

Journal of Mountain Science 2019年第11期16卷 2679-2686页

作者： wu jian-bo WANG Xiao-dan Key Laboratory of Mountain Environment Evolution and Ecological Regulation Institute of Mountain Hazard and Environment CAS

The mechanism that sustains the temporal stability of aboveground net primary production(ANPP)respond to nitrogen deposition is still ***,we investigated the mechanism of temporal stability of ANPP through the effect of N addition on diversity,species asynchrony andportfolio effects in northern Tibet alpine steppe over a period of three *** results showed that the community temporal stability did not significantly correlate with the species richness and Shannon–Wiener *** asynchrony and stability was also not significantly affected by N addition(p>0.05).Furthermore,there was no significant relationship between species asynchrony and temporal *** the value of portfolio effects(z)(z=1.304,95%confidence intervals:1.029–1.597)was more than 1,the portfolio effects was not a primary driver of temporal stability due to the biodiversity being *** above results suggested that the richness,species asynchrony and portfolio effect could not support for mechanism of stability at the alpine *** the results of path analysis,species temporal stability positively supports the community temporal stability in the alpine steppe *** to the character of environment and vegetation of alpine steppe at North Tibet,we inferred that dominance species stability is more important than species richness for the community temporal stability.

关键词： Community temporal stability Species richness Species asynchrony Species temporal stability Portfolio effects Nitrogen deposition

Variation in carbon,nitrogen and phosphorus partitioning between above-and belowground biomass along a precipitation gradient at Tibetan Plateau

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Journal of Mountain Science 2016年第4期13卷 661-671页

作者： HONG jiang-tao WANG Xiao-dan wu jian-bo Institute of Mountain Hazards and Environment Academy of Sciences of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China

Precipitation is a potential factor that significantly affects plant nutrient pools by influencing biomass sizes and nutrient concentrations. However, few studies have explicitly dissected carbon(C), nitrogen(N) and phosphorus(P) pools between above- and belowground biomass at the community level along a precipitation gradient. We conducted a transect(approx. 1300 km long) study of Stipa purpurea community in alpine steppe on the Tibet Plateau of China to test the variation of N pool of aboveground biomass/N pool of belowground biomass(AB/BB N) and P pool of aboveground biomass/P pool of belowground biomass(AB/BB P) along a precipitation gradient. The proportion of aboveground biomass decreased significantly from mesic to drier sites. Along the belt transect, the plant N concentration was relatively stable; thus, AB/BB N increased with moisture due to the major influences by above- and belowground biomass allocation. However, P concentration of aboveground biomass decreased significantly with increasing precipitation and AB/BB P did not vary with aridity because of the offset effect of the P concentration and biomass allocation. Precipitation gradients do decouple the N and P pool of a S. purpurea community along a precipitation gradient in alpine steppe. The decreasing of N:P in aboveground biomass in drier regions may indicate much stronger N limitation in more arid area.

关键词： Biomass allocation Nutrient concentration Qinghai-Tibetan Plateau Alpine steppe Stipa purpurea

Role of PAI-1 in adipose tissue senescence and inflammation in obesity

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西南医科大学学报 2021年第5期44卷 439-444页

作者： XU Jin GAO Qian wu jian-bo Department of Gastroenterology the Affiliated Hospital of Southwest Medical UniversityLuzhou 646000China Drug Discovery Research Center Southwest Medical UniversityLuzhou 646000China Laboratory for Cardio-vascular Pharmacology Department of PharmacologySchool of PharmacySouthwest Medical UniversityLuzhou 646000China

Plasminogen activator inhibitor-1(PAI-1)is a member of the evolutionarily conserved serine pro⁃tease inhibitor *** increased expression of PAI-1 leads to pathological diseases such as vascular diseases,obesity,and metabolic ***-associated secretory phenotype(SASP)mediates tissue damage and plays a role in adipose tissue *** inflammation in adipose tissue is associated with the development of metabolic diseases,including obesity,insulin resistance,and type 2 ***-1 plays a vital role in adipose tissue physiology,glucose metabolism,insulin secretion and sensitivity,inflammation,and macrophage *** article reviews the possible role of PAI-1,as one of the SASP markers,and speculates the potential role of PAI-1 in adipose tissue senescence and inflammatory macrophage infiltration in obesity.

关键词： PAI-1 Adipose tissue Macrophage Senescence

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有机溶剂-微波-水热法制备氢氧化镁晶须

化学工程 2006年第10期34卷 55-58页

作者：吴健松吴健柏李财花石晓波湛江师范学院生命科学与化学学院广东湛江524048 广东省东莞理工学校广东东莞523006 广东省吴川市第一中学广东吴川524500

以青海东台水氯镁石混合物为原料,以含一定量有机溶剂的氢氧化钠为沉淀剂,采用微波-水热法制备了氢氧化镁晶须。实验发现在水热温度为180℃,反应时间为1.5 h的条件下,氢氧化镁晶须产率与有机溶剂在反应体系中的质量分数有关,当质量分数... 详细信息

以青海东台水氯镁石混合物为原料,以含一定量有机溶剂的氢氧化钠为沉淀剂,采用微波-水热法制备了氢氧化镁晶须。实验发现在水热温度为180℃,反应时间为1.5 h的条件下,氢氧化镁晶须产率与有机溶剂在反应体系中的质量分数有关,当质量分数为30%时可获得产率为80%的氢氧化镁晶须,但继续增加有机溶剂的质量分数晶须产率不再增加。扫描电镜照片显示粒子呈晶须形状、粒度分布均匀、分散性好、晶形好、纯度高。本实验不仅生产工艺简单,且生产成本低,具有较高的经济效益,可望充分利用盐湖镁资源进一步中试。

关键词：有机溶剂微波-水热法水氯镁石氢氧化镁晶须

纳米CoO的制备及对MH-Ni电池正极性能的影响

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电源技术 2008年第9期32卷 617-619页

作者：吴建波台州学院物理与电子工程学院物理与材料工程系浙江台州318000

CoO添加剂可以有效地提高MH-Ni电池正极活性材料Ni(OH)2的放电深度,改善正极的综合放电性能。采用真空分解棒状超微CoCO3前驱体制备了粒度均匀的短棒状CoO纳米颗粒,并研究了纳米CoO对氢镍电池正极性能的影响。研究发现,纳米CoO代替普通... 详细信息

CoO添加剂可以有效地提高MH-Ni电池正极活性材料Ni(OH)2的放电深度,改善正极的综合放电性能。采用真空分解棒状超微CoCO3前驱体制备了粒度均匀的短棒状CoO纳米颗粒,并研究了纳米CoO对氢镍电池正极性能的影响。研究发现,纳米CoO代替普通亚微米CoO,可以使电极内部的CoOOH导电网络更均匀、更完整,并抑制g-NiOOH的生成,从而缩短电池制备的静置时间,提高正极的放电比容量和放电中值电压,并缓解电池放电比容量和放电中值电压的退化速度。

关键词： MH-Ni电池正极添加剂纳米CoO 放电比容量

The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel

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Journal of wuhan University of Technology(Materials Science) 2025年第1期40卷 275-282页

作者： GAO Qian LI Jun WANG Xianhui CAO Laifu GONG jian LI bo Central Iron and Steel Research Institute Group Beijing 100081China Shougang Zhixin Electromagnetic Material R&D(Beijing)Co. Ltd.Beijing 101300China Beijing Shougang Co. Ltd.Qian’an 064404China

Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were *** illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically *** effect of precipitate ripening on the Goss texture and magnetic property was *** indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate *** recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}oriented grains growing abnormally and a magnetic induction intensity of ***,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss ***,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 *** a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this *** heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties.

关键词： high temperature annealing heating rate secondary recrystallization grain oriented silicon steel

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan Guo Hong-bo Jin Cong-Feng Qiao Yue-Liang wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

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多方向编组站设计配置的思考

铁道运输与经济 2010年第8期32卷 42-46页

作者：吴健波成都铁路局重庆西站重庆400052

针对多方向编组站的特点,以重庆枢纽新建兴隆场编组站设计为例,提出从改进编组站交换场、编组场、到发场、机车走行线和机务段设置,调整编组站到、解、集、编、发系统功能分工,疏解车站两端咽喉联络线布局等方面入手,改善多方向编组站... 详细信息

针对多方向编组站的特点,以重庆枢纽新建兴隆场编组站设计为例,提出从改进编组站交换场、编组场、到发场、机车走行线和机务段设置,调整编组站到、解、集、编、发系统功能分工,疏解车站两端咽喉联络线布局等方面入手,改善多方向编组站的设计配置,减少多方向车流在编组站接发列车、调车作业中的相互交叉干扰,有效提高编组站的运输效率。

关键词：编组站运输能力配置重庆枢纽

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具有PCSK9调控作用的天然产物研究进展

中草药 2019年第9期50卷 2229-2234页

作者：刘艳罗培吴剑波澳门科技大学中医药学院西南医科大学药物与功能性食品研究中心四川泸州646000

前蛋白转化酶枯草溶菌素9(PCSK9)对血浆低密度脂蛋白胆固醇(LDL-C)的代谢具有调节作用,使PCSK9抑制剂成为心血管领域调脂治疗的热点和生物制剂的开发热点,但生物制剂不良反应大,价格昂贵。目前文献报道许多天然产物具有调节PCSK9的作用... 详细信息

前蛋白转化酶枯草溶菌素9(PCSK9)对血浆低密度脂蛋白胆固醇(LDL-C)的代谢具有调节作用,使PCSK9抑制剂成为心血管领域调脂治疗的热点和生物制剂的开发热点,但生物制剂不良反应大,价格昂贵。目前文献报道许多天然产物具有调节PCSK9的作用,综述天然产物对PCSK9的调节作用及其作用机制,以期为PCSK9的小分子抑制剂开发提供参考。

关键词：前蛋白转化酶枯草溶菌素9 天然产物 PCSK9抑制剂调脂作用作用机制

Biochemical and Morphological Changes in the Lenses of Selenium and/or Vitamin E Deficient Rats

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Biomedical and Environmental Sciences 1994年第2期7卷 109-115页

作者： CAI QIU-YIN CHEN XIAO-SHU ZHU LIAN-ZHEN XUE AN-NA LI WEN-XIAN WANG SHU-QIN PIAO jian-HUA LI JIE SUN CUN-PU wu KE AND CONG jian-bo(Institute of Nutrition and Food Hygiene, Chinese Academy of Preventive Medicine, 29 Nan Wet Road, Beijing 100050, Chin Institute of Nutrition and Food Hygiene Chinese Academy of Preventive Medicine Beijing.

The activities of glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R),superoalde dismutase (SOD) and the contents of malondialdehyde (MDA) and free radicals were measured, and the morphological changes were observed in the lens of control rats, selenium-deficient (SeD) and/or vitamin E deficient (VED) rats. The activities of GSH-Px in the lens of SeD rats decreased significantly. The GSH-Px activities of lens were positively related to erythrocytes selenium level. There was a free radical at g = 2.0015 in the rat lens of all groupe, but the content of free radicals in the lens of SeD group was significantly higher than that of the control group. The free radical content of lens was negatively related to erythrocytes selenium level, as well as the GSH-Px activities in the lens. In vitro, ultraviolet radiation caused the generation of another kind of free radical (g = 2.0097) in the lens of all groups, but the amount of the free radical in the lens of the SeD group was also significantly higher than that of the control group. The activities of SoD and GSSG-R in VED rat lens were significantly decreased. The amount of MDA in the lens of SeD and/or VED rats were significantly increased. The results showed that the decrease of antioaldative capability in the lenses of SeD and/or VED rats accelerated the lipid peroxidation and generation of free radicals. Although only early morphological changes in SeD and/or VED rat lens were observed, it is considered that selenium and vitamin E deficiency may be involved in the occurrence of cataract

关键词： Res GSH Biochemical and Morphological Changes in the Lenses of Selenium and/or Vitamin E Deficient Rats