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Syntheses,Crystal Structures,and Fluorescence Properties of Three Coordination Polymers Constructed Based on Benzoic Acid and Its Derivatives

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Chinese Journal of Structural Chemistry 2017年第12期36卷 2058-2066页

作者： LIU Guang-Zeng CHEN Hong-tai ZHANG Xiu-tang Advanced Material Institute of Research College of Chemistry and Chemical EngineeringQilu Normal UniversityJinan 250013China

Three new different dimensional coordination polymers, namely, [Zn（BA-）2（4,4？-bib）-1.5]n（1）, [Zn（4-Br BA-）2（1,4-bmb）]n（2） and [Mn（4-Br BA）2（4,4？-bib）]n（3） have been assembled through the mixed-ligand synthetic strategy（4-HBr BA = 4-bromobenzoic acid, HBA = benzoic acid, 1,4-bmb = 1,4-bis（1 H-imidazol-4-yl）benzene, 4,4？-bib = 4,4？-bis（imidazolyl）biphenyl）. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses（EA）, powder X-ray diffraction（PXRD）, and thermogravimetric（TG） analyses. Single-crystal X-ray diffraction analysis reveals that the crystals of complexes 1~3 are all in triclinic systems, space group P1. Complexes 1 and 2 are 0D binuclear structures, and 3 is a 1 D chain. Moreover, the solid state fluorescence properties of 1 and 2 have been investigated.

关键词： 4-bromobenzoic acid benzoic acid 1 4-bis[(1H-imidazol-1-yl)methyl]benzene 4 4΄-bis(imidazolyl)biphenyl

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数字经济影响商业经济韧性的实证研究

兰州财经大学学报 2024年第3期40卷 92-108页

作者：唐红涛熊望台谢婷湖南工商大学经济与贸易学院湖南长沙410205 广东财经大学经济学院广东广州510320

商业已成为国民经济运行发展的晴雨表及综合国力的象征,提升商业经济韧性对城市经济高质量发展具有重要意义。基于2011—2020年中国276个地级及以上城市面板数据,构建综合指标体系测度城市商业经济韧性,以2014年我国首次颁布的“宽带中... 详细信息

商业已成为国民经济运行发展的晴雨表及综合国力的象征,提升商业经济韧性对城市经济高质量发展具有重要意义。基于2011—2020年中国276个地级及以上城市面板数据,构建综合指标体系测度城市商业经济韧性,以2014年我国首次颁布的“宽带中国”试点政策为准自然实验,通过多期双重差分模型实证分析数字经济对城市商业经济韧性的影响效应,运用PSM-DID方法、安慰剂检验等进行稳健性检验,研究显示:2011—2020年,全国城市商业经济韧性呈整体上升趋势,年均增长率达6.09%;从各区域来看,城市商业经济韧性呈现沿海向内陆递减趋势;“宽带中国”政策显著提升了城市商业经济韧性,对城市商业创新力的促进作用最明显,其次是恢复力和抵抗力,且作用是即期的。进一步进行异质性检验发现,受城市行政等级及规模影响,“宽带中国”政策对城市商业经济韧性的影响效应在非省会城市和中小规模城市表现为促进作用,但在省会城市和大规模城市影响不显著。为深化数字经济对城市商业经济韧性的推动作用,应促进数字技术同商业企业深入融合;优化数字基础设施建设,充分释放数字经济效能;以数字经济为着力点,推进区域间城市商业经济韧性协调发展。

关键词：数字经济商业经济韧性宽带中国多期双重差分法

Rice OsRAD21-2 is Expressed in Actively Dividing Tissues and its Ectopic Expression in Yeast Results in Aberrant Cell Division and Growth

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Journal of Integrative Plant Biology 2011年第1期53卷 14-24页

作者： Chunyan Gong tang Li Qi Li Longfeng Yan tai Wang Research Center forMolecular &-Deveiopmental Biology Key Laboratory of Photosynthesis & Environmental Molecular Physiology Institute of Botany. the Chinese Academy of Sciences and National Center for Plant Gene Research Beijing 100093 China Graduate School of the Chinese Academy of Sciences. Beiiina 100049 China

Rad21 and its meiotic counterpart Rec8, the key components of the cohesin complex, are essential for sister chromatid cohesion and chromosome segregation in mitosis and meiosis, respectively. In contrast to yeast and vertebrates, which have only two RAD211REC8 genes, the rice genome encodes four Rad21/Rec8 proteins. Here, we report on the cloning and characterization of OsRAD21-2 from rice （Oryza sativa L.）. Phylogenetic analysis of the full-length amino acids showed that OsRad21-2 was grouped into the plant-specific Rad21 subfamily. Semi-quantitative reverse transcription-polymerase chain reaction revealed OsRAD21-2 preferentially expressed in premeiotic flowers. Further RNA in situ hybridization analysis and promoter：：β-glucuronidase staining indicated that OsRAD21-2 was mainly expressed in actively dividing tissues including premeiotic stamen, stem intercalary meristem, leaf meristem, and root pericycle. Ectopic expression of OsRAD21.2 in fission yeast resulted in cell growth delay and morphological abnormality. Flow cytometric analysis revealed that the *** cells were arrested in G2 phase. Our results suggest that OsRad21-2 functions in regulation of cell division and growth.

关键词： Genomes Meristems Growth Hybridization Rice Cells Lymphocytes Yeasts

Liquid-Solid Phase Equilibria of Nb-Si-Ti Ternary Alloys

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Chinese Journal of Aeronautics 2008年第3期21卷 275-280页

作者： Bao Jing Huang Qiang tang Liang Geng tai Zhao Xinqing Ma Chaoli School of Materials Science and Engineering Beijing University of Aeronautics and Astronauties Beijing 100083 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

To determine the liquid-solid phase equilibria of the Nb-Si-Ti ternary system, Nb-Si-Ti alloys of different compositions are prepared. By means of scanning electron microscopy （SEM）, X-ray diffraction （XRD） and electron probe microanalysis （EPMA）, the phases in the alloys, such as Si-based solutions, Ti（Nb）Si, Ti（Nb）Si2, Nb（Ti）Si2, Ti（Nb）5Si4, Nb（Ti）5Si3, Ti（Nb）5Si3, Nb（Ti）3Si and Nb-based solutions are identified, and the phase evolution is analyzed. As a result, the microstmctural and microchemical evidence provides a clear definition of the Nb-Si-Ti liquidus surface projection and indicates that the ternary phase diagram has seven transition reactions.

关键词： Nb-Si-Ti ternary phase equilibria liqudus projection

Increased hsp70 of glucocorticoid receptor complex induced by scald and heat stress and its possible effect on the affinity of glucocorticoid receptor

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Chinese Medical Journal 2010年第13期123卷 1780-1785页

作者： WANG Xiao-hui tang Hong-tai LU Jian XIA Zhao-fan Department of Physiology Shanghai University of Sport Shanghai 200438 China Department of Bums Changhai Hospital the Second Military Medical University Shanghai 200433 China Department of Pathophysiology the Second Military Medical University Shanghai 200433 China

Background Glucocorticoid （GC） insensitivity/GC resistance is an important etiological and prognostic factor in multiple diseases and pathophysiological processes such as scald, shock and asthma. The function of GC was mediated by glucocorticoid receptor （GR）. Scald not only decreased the expression of GR but also reduced the affinity of GR, which played an important role in GC resistance in scalded rats. Whereas the molecular mechanism responsible for the decrease of GR affinity resulted from scald remains unclear. Recent studies showed that the changes of heat shock proteins （hsp） especially hsp90 and hsp70 of GR heterocomplex were associated with GR low affinity in vitro. Methods The affinity of GR in hepatic cytosols and in the cytosols of SMMC-7721 cells were determined by radioligand binding assay and scatchard plot. GR heterocomplex in cytosols were captured by coimmunoprecipation and the levels of hsp90 and hsp70 of GR complex were detected by quantitative Western blotting. Results Similar with that of hepatic cytosol of scalded rats, a remarkable decrease of GR affinity was also found in the cytosol of heat stressed SMMC-7721 cells. The level of hsp70 of GR complex in hepatic cytosol of scalded rats （30% total body surface area immersion scald） and in cytosol of heat stressed human hepatocarcinoma cell line SMMC-7721 were both increased by 1.5 fold, whereas no change of hsp90 in GR heterocomplex was found. According to the correlation analysis, there may be a positive relationship between increased hsp70 of GR complex and decreased GR affinity in the cytosols. Conclusions The primary results indicated that the level of hsp70 of GR heterocomplex was increased in the hepatic cytosol of scalded rats and the cytosol of heat stressed SMMC-7721 cells. The increase of hsp70 of GR complex might be associated with the decrease of GR affinity.

关键词： hsp70 glucocorticoid receptor affinity scald heat stress

用于农药喷施的液力式喷头雾化与沉积分布特性分析

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农药学学报 2024年第1期26卷 168-178页

作者：王士林陆岱鹏 Jonathan van BEEK Ingrid ZWERTVAEGHER 王伟徐陶刘春唐玉新李雪 David NUYTTENS 江苏省农业科学院农业设施与装备研究所南京210014 农业部长江中下游设施农业工程重点实验室南京210014 佛兰德斯农业、渔业和食品研究所比利时梅勒尔贝克9820

在众多类型的喷头中,液力式雾化喷头因其雾化量大、能耗低、设备简单、经济性好而得到更广泛应用。研究液力式喷头的雾化与沉积特性对改善农药喷施效果具有重要的指导意义。为明确液力式喷头的类型和喷雾参数对其雾化和沉积特性的影响,... 详细信息

在众多类型的喷头中,液力式雾化喷头因其雾化量大、能耗低、设备简单、经济性好而得到更广泛应用。研究液力式喷头的雾化与沉积特性对改善农药喷施效果具有重要的指导意义。为明确液力式喷头的类型和喷雾参数对其雾化和沉积特性的影响,本文对6种类型的液力式喷头(标准扇形雾XR 110-015、防飘扇形雾DG 110-015、射流扇形雾AIXR 110-015、射流扇形雾AI 110-015、空心圆锥雾TXA 80-015和射流空心圆锥雾AITXA 80-015)的雾滴粒径、雾滴沉降速度以及沉积分布进行了测试。结果表明:6种供试喷头的雾滴粒径均随喷雾压力的增大而减小,不同喷雾压力下细雾滴(XR 110-015)和中等雾滴喷头(DG 110-015)的体积中值直径(D_(v0.5))差异较小,而粗雾滴(AIXR 110-015)和超粗雾滴喷头(AI 110-015和AITXA 80-015)对喷雾压力的敏感性更强,其雾滴的D_(v0.5)值随着喷雾压力的增加而急剧下降。雾滴沉降速度与分布特征主要由喷头类型决定,喷雾压力对雾滴沉降速度的影响较小,同一喷头在不同喷雾压力下的雾滴沉降速度分布趋势相似。相同喷雾压力下,细雾滴喷头的平均沉降速度(Vavg)高于其体积中值沉降速度(V_(v0.5)),但随着喷头雾滴的增大,中雾滴喷头和粗雾滴喷头的V_(v0.5)超过其Vavg,且雾滴的粒径越大两者差值越明显。雾滴的沉积结果显示,不同喷雾压力下各喷头的喷雾液流失率均在7.82%~9.75%范围内,各喷头在不同喷雾压力下的流量相似,且略低于其名义流量。喷雾压力对DG 110-015、XR 110-015和AIXR 110-015喷头的雾滴沉积分布均匀性无显著影响,但较高的喷雾压力可提高AITXA 80-015和TXA 80-015喷头的雾滴沉积分布均匀性。本研究可为田间施药时液力式喷头的选择和作业参数的优化提供理论指导和技术参考。

关键词：农药喷施液力式喷头喷雾雾滴谱雾滴沉降速度沉积

数智化背景下全周期农业创新人才培养模式与实践路径研究

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安徽农业科学 2024年第16期52卷 276-278页

作者：梁远唐立强毕文泰渤海大学管理学院辽宁锦州121013

数字化与智能化是新时期高等教育研究的热点议题。当前,农业创新人才培养要主动适应数字化、智能化的时代要求,培养具备高附加值的高质量人才,贯穿农业创新人才培养全周期。从逻辑起点、价值取向和最终目标3个方面探析数智化背景下全周... 详细信息

数字化与智能化是新时期高等教育研究的热点议题。当前,农业创新人才培养要主动适应数字化、智能化的时代要求,培养具备高附加值的高质量人才,贯穿农业创新人才培养全周期。从逻辑起点、价值取向和最终目标3个方面探析数智化背景下全周期农业创新人才培养的理论逻辑,提出数智化背景下全周期农业创新人才培养的“战略引导+政策扶持”模式、“知识供给+产教融合”模式和“高校+企业+政府三方协同”模式,并在此基础上进一步提出全周期农业创新人才培养的四螺旋上升路径和三方循环路径,进而以数字经济与高质量农业创新人才助推国家富强与民族振兴。

关键词：全周期数字技术农业创新人才培养模式实践路径

Pressure fluctuation characteristics in the pressurization unit of a multiphase pump

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Journal of Hydrodynamics 2021年第6期33卷 1230-1241页

作者： Guang-tai Shi Zong-ku Liu Ye-xiang Xiao Xue-lin tang Xiao-bing Liu Key Laboratory of Fluid and Power Machinery Ministry of EducationXihua UniversityChengdu 610039China College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China State Key Laboratory of Hydroscience and Engineering and Department of Energy and Power Engineering Tsinghua UniversityBeijing 100084China Beijing Engineering Research Centre of Safety and Energy Saving Technology for Water Supply Network System China Agricultural UniversityBeijing 100083China

The tip clearance induces the tip leakage vortex(TLV),which has a great impact on the pressure fluctuation characteristics of the multiphase *** investigate the effect of the tip clearance on the pressure fluctuations,based on the Reynolds time-averaged Navier-Stokes equation and the shear stress transfer(SST)k-ωturbulence model,the three-dimensional turbulent flow in the pump is numerically simulated for different tip clearances in the water and gas-liquid two-phase cases by using the ANSYS CFX software and the results are verified with experimental *** is shown the greater pressure fluctuation intensity corresponds with the TLV both in the water and gas-liquid two-phase *** the meantime,the location of the maximum pressure fluctuation intensity is related to the tip clearance *** addition,for different tip clearances,the pressure fluctuation intensity with the rotor and stator interaction(RSI)is relatively *** difference is that when R_(tc)=1.5 mm,the pressure fluctuation intensity near the impeller middle point is also relatively *** the whole,the pressure fluctuation intensity in the gas-liquid two-phase case is larger than that in the water ***,the gas causes the frequency of the high-amplitude pressure fluctuation in the impeller and the diffuser to be shifted from 7 f_(n)(f_(n) denotes impeller rotational frequency)and 3 f_(n) to the low-frequency region,*** pressure fluctuations at the blade-passing frequency(BPF)and the multiple BPFs gradually ***,the amplitude at the dominant frequency in the gas-liquid two-phase case is at least one order of magnitude smaller than that in the water case,and the peak-to-peak value of the pressure fluctuation is also much smaller.

关键词： Multiphase pump gas void faction pressure fluctuation intensity tip leakage vortex(TLV) numerical simulation

Development and application of a throughflow method for high-loaded axial flow compressors

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Science China(Technological Sciences) 2016年第1期59卷 93-108页

作者： LI Bo GU Chun Wei LI Xiao tang LIU tai Qiu XIAO Yao Bing Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Thermal EngineeringTsinghua UniversityBeijing 100084China Shenyang Engine Design and Research Institute Shenyang 110015China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100191China

In this paper, a novel engineering platform for throughflow analysis based on streamline curvature approach is developed for the research of a 5-stage compressor. The method includes several types of improved loss and deviation angle models, which are combined with the authors' adjustments for the purpose of reflecting the influences of three-dimensional internal flow in high-loaded multistage compressors with higher accuracy. In order to validate the reliability and robustness of the method, a series of test cases, including a subsonic compressor P&W 3S1, a transonic rotor NASA Rotor 1B and especially an advanced high pressure core compressor GE E^3 HPC, are conducted. Then the computation procedure is applied to the research of a 5-stage compressor which is designed for developing an industrial gas turbine. The overall performance and aerodynamic configuration predicted by the procedure, both at design- and part-speed conditions, are analyzed and compared with experimental results, which show a good agreement. Further discussion regarding the universality of the method compared with CFD is made afterwards. The throughflow method is verified as a reliable and convenient tool for aerodynamic design and performance prediction of modern high-loaded compressors. This method is also qualified for use in the further optimization of the 5-stage compressor.

关键词： throughflow method multi-stage compressor high-loaded loss and deviation angle models streamline curvature aerodynamic design performance prediction