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Geochronologic Constraints on the Magmatic Underplating of the Gangdisê Belt in the India-Eurasia Collision: Evidence of SHRIMP II Zircon U-Pb Dating

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Acta Geologica Sinica(English Edition) 2005年第6期79卷 787-794页

作者： DONG Guochen MO Xuanxue ZHAO Zhidan GUO Tieying wang liangliang CHEN Tao State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 School of Earth Science and Resources China University of Geosciences Beijing 100083 Hebei B.rea. of Geology and Mineral Exploration and Development Shijiazhuang Hebei 050081

Abundant small mafic intrusions occur associated with granitoids along the Gangdise^ magmatic belt. In addition to many discrete gabbro bodies within the granitoid plutons, a gabbro-pyroxenite zone occurs along the southern margin of the Gangdise^ belt to the north of the Yarlung Zangbo suture. The mafic intrusion zone spatially corresponds to a strong aeromagnetic anomaly, which extends -1400 km. The mafic intrusions consist of intermittently distributed small bodies and dikes of gabbro and dolerite with accumulates of pyroxenite, olivine pyroxenite, pegmatitic pyroxenite and amphibolite. Much evidence indicates that the Gangdise^ gabbro-pyroxenite assemblage is most likely a result of underplating of mantle-derived magma. Detailed field investigation and systematic sampling of the mafic rocks was conducted at six locations along the Lhasa-Xigaze^ segment of the mafic intrusive zone, and was followed by zircon SHRIMP Ⅱ U-Pb dating. In addition to the ages of two samples previously published （47.0±1 Ma and 48.9±1.1 Ma）, the isotopic ages of the remaining four gabbro samples are 51.6±1.3Ma, 52.5±3.0 Ma, 50.2±4.2Ma and 49.9±1.1Ma. The range of these ages （47-52.5 Ma） provide geochronologic constraints on the Eocene timing of magma underplating beneath the Gangdise^ belt at ca. 50 Ma. This underplating event post-dated the initiation of the India-Eurasia continental collision by 15 million years and was contemporaneous with a process of magma mixing. The SHRIMP Ⅱ U-Pb isotopic analysis also found several old ages from a few zircon grains, mostly in a range of 479-526 Ma （weighted average age 503±10 Ma）, thus yielding information about the pre-existing lower crust when underplating of mafic magma took place. It is believed that magma underplating was one of the major mechanisms for crustal growth during the Indian-Eurasia collision, possibly corresponding in time to the formation of the 14-16 km-thick ＂crnst-mantle transitional zone＂ characterized by Vp=6.85-6.9 km/s.

关键词： SHRIMP U-Pb dating mafic intrusion gabbro underplating the Gangdise^ Tibet

Disclosure of government financial information and the cost of local government's debt financing——Empirical evidence from provincial investment bonds for urban construction

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China Journal of Accounting Research 2016年第3期9卷 191-206页

作者： Zhibin Chen Jun Pan liangliang wang Xiaofeng Shen School of Economics & Management Southeast University School of Finance & Economics Jiangsu University

China's slowing economic growth and rapid urbanization have made local government debt financing a significant *** study uses a sample of China's provincial government data for the 2006–2012 period to examine the effect of the disclosure of financial information by local governments on their debt financing *** results show that financial information disclosure is conducive to public supervision and enhances government credibility,leading to a decrease in the cost of debt ***,increased government economic intervention increases the strength of the association between financial information disclosure and the cost of debt *** government audit prevention function weakens the strength of the association between financial information disclosure and the cost of debt financing.

关键词： Local government debt Cost of debt financing Government financial information disclosure Government intervention Government audit

Asymmetric Total Synthesis towards the Simplified Analogs of Antibiotic Elansolid A

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有机化学 2024年第7期44卷 2350-2362页

作者： Yang Shuai Wu Jie wang liangliang State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201 University of Chinese Academy of Sciences Beijing 101408

Natural product elansolid A belongs to one type of polyketide macrolactone with promising antibiotic ***-viously,the first total synthesis of elansolid A in 28 longest linear sequence(LLS)and 41 steps in total has been ***,the simplified analog of elansolid A,featured with a cyclohexyl-fused 19-memebered macrolactone,was proposed,and its asymmetric total synthesis based on a convergent strategy and key reactions exemplified by desymmetric alcoholysis of anhydride,Pd-catalyzed Stille coupling,Suzuki-Miyaura coupling as well as Mukaiyama macrolactonization was finished.

关键词： asymmetric total synthesis coupling reaction simplified analog elansolid A

SR9009联合吲哚丙酸通过核因子κB信号通路减轻C2C12成肌细胞的炎症反应

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中国组织工程研究 2025年第6期29卷 1220-1229页

作者：姬慧慧蒋旭张志敏邢运虹王亮亮李娜宋雨庭罗旭光崔慧林曹锡梅山西医科大学组织学与胚胎学教研室山西省晋中市030604 山西医科大学法医学院山西省晋中市030604 山西医科大学微生物免疫学教研室山西省晋中市030604 山西医科大学山西省临床级细胞治疗转化中试基地山西省晋中市030604

背景:钟基因Rev-erbα参与调节炎症,但激活Rev-erbα会增加心脑血管疾病风险。为降低相关风险,探索Rev-erbα激动剂SR9009联合其他药物来减轻骨骼肌成肌细胞炎症,奠定治疗炎症相关性骨骼肌萎缩的理论基础。目的:探讨脂多糖刺激C2C12成... 详细信息

背景:钟基因Rev-erbα参与调节炎症,但激活Rev-erbα会增加心脑血管疾病风险。为降低相关风险,探索Rev-erbα激动剂SR9009联合其他药物来减轻骨骼肌成肌细胞炎症,奠定治疗炎症相关性骨骼肌萎缩的理论基础。目的:探讨脂多糖刺激C2C12成肌细胞时吲哚丙酸、SR9009与核因子κB信号通路的关系。方法:①1μg/mL脂多糖刺激C2C12成肌细胞,RNA转录组测序结合KEGG通路富集分析信号通路。②CCK-8法检测C2C12成肌细胞活性,筛选吲哚丙酸的最佳给药浓度;然后将细胞分为空白对照组、脂多糖(1μg/mL)组、SR9009(10μmol/L)+脂多糖组、吲哚丙酸(80μmol/L)+脂多糖组、吲哚丙酸+SR9009+脂多糖组,ELISA检测细胞上清液中白细胞介素6水平,RT-qPCR检测白细胞介素6、肿瘤坏死因子α、Toll样受体4、CD14 mRNA表达,Western blot检测NF-κB p65、p-NF-κB p65蛋白表达。③siRNA敲减Rev-erbα,RT-qPCR评估敲减效率,检测白细胞介素6、肿瘤坏死因子αmRNA表达。结果与结论:①与空白对照组比较,脂多糖时间依赖性抑制成肌细胞融合形成肌管,白细胞介素6、肿瘤坏死因子αmRNA表达水平升高,细胞上清液中白细胞介素6水平显著升高;KEGG通路分析支持脂多糖刺激激活核因子κB信号通路。②吲哚丙酸浓度>80μmol/L时抑制C2C12成肌细胞活性;吲哚丙酸和SR9009通过抑制核因子κB信号通路发挥抗炎作用,降低白细胞介素6、肿瘤坏死因子α、Toll样受体4、CD14 mRNA表达水平,p-NF-κB p65/NF-κB p65蛋白表达比值低于脂多糖组。SR9009联合吲哚丙酸显著降低脂多糖诱导的炎症,Toll样受体4、CD14、白细胞介素6和肿瘤坏死因子αmRNA表达水平进一步下调,p-NF-κB p65/NF-κB p65蛋白表达比值显著低于吲哚丙酸+脂多糖组和SR9009+脂多糖组。③Rev-erbα随脂多糖刺激时间依赖性升高;siRNA敲减Rev-erbα效率达58%以上,成功敲减Rev-erbα后添加脂多糖,白细胞介素6和肿瘤坏死因子αmRNA表达较脂多糖组显著上调。④结果说明,Rev-erbα可以作为调节炎症反应的靶点,SR9009靶向激活Rev-erbα联合吲哚丙酸能抑制核因子κB信号通路显著减轻C2C12成肌细胞的炎症反应,联合抗炎效果优于单独干预。

关键词： Rev-erbα SR9009 吲哚丙酸脂多糖核因子κB信号通路 C2C12成肌细胞

Interference at the single-photon level based on silica photonics robust against channel disturbance

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Photonics Research 2021年第2期9卷 222-228页

作者： XIAO LI MEIZHEN REN JIASHUN ZHANG liangliang wang WEI CHEN YUE wang XIAOJIE YIN YUANDA WU JUNMING AN State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Division of Quantum Materials and Devices Beijing Academy of Quantum Information SciencesBeijing 100193China Laboratory of Quantum Information CASUniversity of Science and Technology of ChinaHefei 230026China

Quantum key distribution(QKD) provides a solution for communication of unconditional security. However,the quantum channel disturbance in the field severely increases the quantum bit-error rate, degrading the performance of a QKD system. Here we present a setup comprising silica planar light wave circuits(PLCs), which is robust against the channel polarization disturbance. Our PLCs are based on the asymmetric Mach–Zehnder interferometer(AMZI), integrated with a tunable power splitter and thermo-optic phase modulators. The polarization characteristics of the AMZI PLC are investigated by a novel pulse self-interfering method to determine the operation temperature of implementing polarization insensitivity. Over a 20 km fiber channel with 30 Hz polarization scrambling, our time-bin phase-encoding QKD setup is characterized with an interference fringe visibility of 98.72%. The extinction ratio for the phase states is kept between 18 and 21 d B for 6 h without active phase correction.

关键词： polarization channel interferometer

纳米微粒及其分散剂对溴化锂溶液表面张力和沸腾温度的影响

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化工学报 2014年第11期65卷 4315-4320页

作者：解国珍王亮亮北京建筑大学环境与能源工程学院建筑热能系北京100044

在纯溴化锂溶液中加入纳米微粒或分散剂,对比测试其与纯溴化锂溶液的表面张力和沸腾温度的数据,并从所用分散剂的分子结构和纳米微粒的尺寸及外部轮廓的角度出发,定性推测不同种类分散剂及纳米微粒对溴化锂溶液表面张力和沸腾温度的影... 详细信息

在纯溴化锂溶液中加入纳米微粒或分散剂,对比测试其与纯溴化锂溶液的表面张力和沸腾温度的数据,并从所用分散剂的分子结构和纳米微粒的尺寸及外部轮廓的角度出发,定性推测不同种类分散剂及纳米微粒对溴化锂溶液表面张力和沸腾温度的影响。试验发现,添加分散剂溶液的表面张力明显降低,其沸腾温度也相应减小;固体纳米微粒因其填充加热表面凹坑使溶液的沸腾温度有所升高。对于加入纳米微粒及其分散剂的溴化锂溶液,溶液表面张力衰减的正效应因素和纳米微粒填充凹坑的负效应因素的耦合影响将对其沸腾温度产生重要影响。

关键词：纳米微粒分散剂溴化锂溶液表面张力沸腾温度

Research on Changes in Risk of Chilling Damage to Maize in Heilongjiang Province since 1980

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Meteorological and Environmental Research 2014年第4期5卷 23-27页

作者： Li Shuai Chen Li wang liangliang Qin Xue Heilongjiang Research Institute of Meteorological Science Harbin Meteorological Bureau

Based on data of daily average temperature observed during maize growing period as well as data of different growing periods of maize at 24 meteorological stations in Heilongjiang Province from 1980 to 2010, changes in risk of chilling damage to maize since 1980 were analyzed. Initially, the risk of the hazard factor was calculated by adopting the criterion of ＂Comprehensive Decision System of Chilling Damage to Maize in Heilongjiang Province＂. Then, choosing the planting area of maize at 75 stations as the exposure degree index, risk zones of exposure degree were concluded. Afterwards, risk zones of maize sensitivity to chilling damage were outlined based on maize yield per unit area. At last, a comprehensive evaluation model of chilling damage to maize in Heilongjiang Province was established, and Heilongjiang Province was divided into 5 grades of risk zones according to the model. The results showed that compared with the period before 1995, the risk of chilling damage to maize was severer in the west area of Songnen Plain, and previous sub-low or medium risk of chilling damage to maize in the west of Sanjiang Plain changed into subhigh or hi qh risk since the middle 1980s.

关键词： Chilling damage to maize Change of risk Heilongjiang Province China

25 × 50 Gbps wavelength division multiplexing silicon photonics receiver chip based on a silicon nanowire-arrayed waveguide grating

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Photonics Research 2019年第6期7卷 659-663页

作者： ZHI LIU JIASHUN ZHANG XIULI LI liangliang wang JIANGUANG LI CHUNLAI XUE JUNMING AN BUWEN CHENG State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of SciencesBeijing 100083 China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049 China

A high-performance monolithic integrated wavelength division multiplexing silicon(Si) photonics receiver chip is fabricated on a silicon-on-insulator platform. The receiver chip has a 25-channel Si nanowire-arrayed waveguide grating, and each channel is integrated with a high-speed waveguide Ge-on-Si photodetector. The central wavelength, optical insertion loss, and cross talk of the array waveguide grating are 1550.6 nm, 5–8 dB, and-12 –-15 dB, respectively. The photodetectors show low dark current density of 16.9 mA∕cm^2 at-1 V and a high responsivity of 0.82 A/W at 1550 nm. High bandwidths of 23 and 29 GHz are achieved at 0 and-1 V, respectively. Each channel can operate at 50 Gbps with low input optical power even under zero bias,which realizes an aggregate data rate of 1.25 Tbps.

关键词： division chip Gbps optical bias has can dB

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金融危机冲击、融资约束与公司避税

南开管理评论 2016年第1期19卷 155-168页

作者：王亮亮东南大学经济管理学院财务与会计系

金融危机对公司行为的影响吸引了理论界和实务界的共同关注。由于企业所得税是公司重要的现金支出,而且公司避税在世界范围内普遍存在,因而从公司避税活动视角探究金融危机的影响显得尤为重要,然而已有文献关注此问题的还不多。鉴于此,... 详细信息

金融危机对公司行为的影响吸引了理论界和实务界的共同关注。由于企业所得税是公司重要的现金支出,而且公司避税在世界范围内普遍存在,因而从公司避税活动视角探究金融危机的影响显得尤为重要,然而已有文献关注此问题的还不多。鉴于此,本文首先检验金融危机对公司避税的影响,并进一步检验融资约束程度、外部金融市场环境等对二者间关系的调节作用。检验结果表明,金融危机期间,伴随外部融资环境恶化,公司的内源融资需求提高,另外风险转移倾向也会变得更为明显,这些都使得公司的避税程度显著提高;与融资不受约束公司相比,融资约束公司金融危机期间避税程度提高更为明显;伴随公司所处地区金融市场化程度的提高,金融危机对公司避税程度的影响被削弱。本文的研究成果不仅丰富了金融危机微观作用机制方面的学术文献,而且还提供了公司避税程度影响因素方面新的经验证据。

关键词：金融危机公司避税融资约束金融市场化