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Journal of Integrative Agriculture 2016年第3期15卷 502-511页

作者： ZHAO Yong-ying WANG Xiang WEI Li WANG Jing-xuan yin jun National Engineering Research Center for Wheat Collaborative Innovation Center of Henan Grain CropsState Key Laboratory of Wheat and Maize Crop ScienceCollege of AgricultureHenan Agricultural UniversityZhengzhou 450002P.R.China National Laboratory of Wheat Engineering Key Laboratory of Wheat Biology and Genetic Breeding in Central Huang-Huai RegionMinistry of AgriculturalKey Laboratory of Wheat Biology of Henan ProvinceWheat Research InstitutionHenan Academy of Agricultural SciencesZhengzhou 450002P.R.China

Photoperiodic response is an important characteristic that plays an important role in plant adaptability for various environments. Wheat cultivars grow widely and have high yield potential for the strong photoperiod adaptibility. To assess the photoperiodic response of different genotypes in wheat cultivars, the photoperiodic effects of the Ppd-D1 alleles and the expressions of the related TaGI, TaCO and Ta FT genes in Liaochun 10 and Ningchun 36 were investigated under the short-day（6 h light, SD）, moderate-day（12 h light, MD） and long-day（24 h light, LD） conditions. Amplicon length comparison indicated that the promoter of Ppd-D1 in Ningchun 36 is intact, while Liaochun 10 presented the partial sequence deletion of Ppd-D1 promoter. The durations of all developmental stages of the two cultivars were reduced by subjection to an extended photoperiod, except for the stamen and pistil differentiation stage in the Liaochun 10 cultivar. The expression levels of the Ppd-D1 alleles and the TaGI, TaCO and TaFT genes associated with the photoperiod pathway were examined over a 24-h period under SD and MD conditions. The relationships of different photoperiodic responses of the two cultivars and the expression of photoperiod pathway genes were analyzed accordingly. The photoperiod insensitive（PI） genotype plants flower early under SD; meanwhile, the abnormal expression of the Ppd-D1 a allele is accompanied with an increase in Ta FT1 expression and the TaCO expression variation. The results would facilitate molecular breeding in wheat.

关键词： wheat photoperiod spike differentiation heading gene expression Ppd-D1

数字经济的僵尸企业治理效应——来自中国工业企业的证据

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财经问题研究 2024年第6期 55-66页

作者：尹俊雅王海毛丰付浙江工商大学泰隆金融学院浙江杭州310018 浙江工商大学经济学院浙江杭州310018

数字经济是推进中国式现代化的重要驱动力,依托数字经济助力僵尸企业治理对于推动中国经济高质量发展至关重要。本文基于全国工商企业注册数据和中国工业企业数据,采用双向固定效应模型实证研究了数字经济对僵尸企业的影响及其作用机制... 详细信息

数字经济是推进中国式现代化的重要驱动力,依托数字经济助力僵尸企业治理对于推动中国经济高质量发展至关重要。本文基于全国工商企业注册数据和中国工业企业数据,采用双向固定效应模型实证研究了数字经济对僵尸企业的影响及其作用机制。研究结果显示:数字经济发展水平提高能够显著降低僵尸企业比重,可发挥僵尸企业治理效应;数字经济的僵尸企业治理效应在非资本密集型行业、非出口型行业、非资源型地区和经济发展压力较小地区更明显;数字经济主要通过强化市场竞争、激励技术创新、缓解融资约束和增强企业自生能力发挥僵尸企业治理效应。本文可以为更好地释放数字经济红利和加速推进中国经济高质量发展提供借鉴。

关键词：数字经济僵尸企业市场竞争技术创新融资约束

The phenylalanine ammonia-lyase gene family in Isatis indigotica Fort.:molecular cloning,characterization,and expression analysis

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Chinese Journal of Natural Medicines 2016年第11期14卷 801-812页

作者： MA Rui-Fang LIU Qian-Zi XIAO ying ZHANG Lei LI Qing yin jun CHEN Wan-Sheng Development and Utilization Key Laboratory of Northeast Plant Materials School of Traditional Chinese Materia MedicaShenyang Pharmaceutical University College of Pharmacy Jiamusi University Department of Pharmacy Changzheng Hospital Second Military Medical University Department of Pharmaceutical Botany School of Pharmacy Second Military Medical University

Phenolic compounds, metabolites of the phenylpropanoid pathway, play an important role in the growth and environmental adaptation of many plants. Phenylalanine ammonia-lyase(PAL) is the first key enzyme of the phenylpropanoid pathway. The present study was designed to investigate whether there is a multi-gene family in I. Indigotic and, if so, to characterize their properties. We conducted a comprehensive survey on the transcription profiling database by using tBLASTn analysis. Several bioinformatics methods were employed to perform the prediction of composition and physicochemical characters. The expression levels of IiPAL genes in various tissues of I. indigotica with stress treatment were examined by quantitative real-time PCR. Protoplast transient transformation was used to observe the locations of IiPALs. IiPALs were functionally characterized by expression with pET-32a vector in Escherichia colis strain BL21(DE3). Integration of transcripts and metabolite accumulations was used to reveal the relation between IiPALs and target compounds. An new gene(IiPAL2) was identified and both IiPALs had the conserved enzymatic active site Ala-Ser-Gly and were classified as members of dicotyledon. IiPAL1 and IiPAL2 were expressed in roots, stems, leaves, and flowers, with the highest expression levels of IiPAL1 and IiPAL2 being observed in stems and roots, respectively. The two genes responded to the exogenous elicitor in different manners. Subcellular localization experiment showed that both IiPALs were localized in the cytosol. The recombinant proteins were shown to catalyze the conversion of L-Phe to trans-cinnamic acid. Correlation analysis indicated that Ii PAL1 was more close to the biosynthesis of secondary metabolites than IiPAL2. In conclusion, the present study provides a basis for the elucidation of the role of Ii PALs genes in the biosynthesis of phenolic compounds, which will help further metabolic engineering to improve the accumulation of bioactive components in I.indigotica.

关键词： Phenylalanine ammonia-lyase Isatis indigotica Fort Phenolic compounds Lignan Correlation analysis

准低温条件下不同含水量玉米储存品质和微观结构变化

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粮油食品科技 2024年第1期32卷 129-138页

作者：谭晓雨丁玉琴丁明军张忠杰尹君中南林业科技大学食品科学与工程学院湖南长沙410000 保定市粮油质量检测中心河北保定071000 国家粮食和物资储备局科学研究院粮食储运研究所北京100037 粮食储运国家工程研究中心北京100037

玉米因富含营养物质、自身胚部大,易受到虫霉等侵染,造成其品质劣变,因此玉米保质保鲜储存具有一定的挑战,为此需要明晰玉米的储存品质规律与变化。以初始含水量分别为13.04%、14.03%、14.99%玉米为研究对象,以常温储藏环境(25℃)为对... 详细信息

玉米因富含营养物质、自身胚部大,易受到虫霉等侵染,造成其品质劣变,因此玉米保质保鲜储存具有一定的挑战,为此需要明晰玉米的储存品质规律与变化。以初始含水量分别为13.04%、14.03%、14.99%玉米为研究对象,以常温储藏环境(25℃)为对照研究在温度20℃准低温储存期间玉米的容重、脂肪酸值、发芽率、霉菌活动等品质与安全指标变化规律及玉米籽粒微观结构变化。实验结果表明:在20℃下,三个不同初始含水量的玉米的发芽率、脂肪酸值、容重较25℃储存环境下变化均较慢,均处于宜存范围。真菌孢子数随储存时间延长而急剧上升,且与玉米初始水分含量具有显著性相关,即14.99%的玉米储存至120d,真菌孢子数量级别已达到严重危害程度,13.04%、14.03%、14.99%玉米的安全储存期分别为180d、180d和100d。储存期间的玉米微观结构发生了渐变,即表面由平滑整齐变为凹凸褶皱,淀粉颗粒排列由结构紧密逐渐变为稀疏无序。由此可知,玉米在(准)低温储存条件下,储存时间和初始含水量是影响玉米储存品质和微观结构变化的主要因素。研究结果为实现玉米产后保质减损提供新的视角。

关键词：玉米准低温储藏品质储存微观结构

Study on Absorption and Regeneration Performance of Novel Hybrid Solutions for CO_2 Capture

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China Petroleum Processing & Petrochemical Technology 2016年第1期18卷 66-72页

作者： Gao Jie yin jun Zhu Feifei Chen Xin Tong Ming Kang Wanzhong Zhou Yanbo Lu jun Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education East China University of Science & Technology SINOPEC Ningbo Engineering Co. Ltd.

Recently, a kind of hybrid solution MEA-methanol shows a better CO_2 capture performance over aqueous MEA solution. However, the vaporization of methanol is the biggest disadvantage that hinders its application, so it is necessary to minimize the vaporization of methanol during both the absorption and regeneration processes. In this work, two kinds of hybrid solutions were studied and compared with aqueous MEA solution and MEA-methanol solution, including MEA/TEA/methanol solution and MEA/glycerol/methanol solution. The absorption property of MEA/glycerol/methanol solution is better than aqueous MEA solution within a certain period of time and the absorption property of MEA/TEA/methanol solution is too poor to be used in CO_2 capture. By increasing the concentration of TEA and decreasing the concentration of MEA, the absorption rate, CO_2 capture efficiency and absorption capacity all decreased. Upon adding glycerol, the cyclic capacity decreased and the generation temperature increased, and moreover, the density and viscosity also increased considerably. So after adding TEA and glycerol, the CO_2 capture performance of MEAmethanol solvent cannot be improved.

关键词：混合溶液吸收特性捕集效率再生性能二氧化碳甲醇溶液捕获性能 MEA

Study on CO_2 Absorption by Aqueous Benzylamine and Its Formulations with Monoethanolamine as a Component for Post-Combustion Capture Process

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China Petroleum Processing & Petrochemical Technology 2016年第3期18卷 7-14页

Benzylamine(BZA) has been identified as a promising candidate for CO_2 capture process; however the evaluation of BZA in the packed column was very few. Thus, in this work, the absorption and regeneration performance of unblended BZA solvent as well as a series of amine concentrations and ratios in the formulations were studied using a semibatch bubbling reactor. And due to the formation of ivory-white precipitates in solvents containing higher BZA ratios, a 4:1 molar ratio of MEA/BZA mixed solvent was used to study its performance in a pilot-scale test bed. The results showed that a higher BZA ratio in the MEA/BZA mixed solvent resulted in a faster absorption rate, a higher mass transfer and heat transfer rate and a better cyclic performance, but the mass transfer rate of BZA decreased more quickly than MEA with the increase of CO_2 loading of the solvents. In addition, at high CO_2 loading in the MEA/ BZA mixed solvent with a molar ratio of 4:1, the ivory-white precipitates were generated which could cause blockage of the packing in the absorber, the stripper and the liquid pipelines.

关键词： benzylamine (BZA) monoethanolamine (MEA) post combustion CO2 capture pilot plant mass transfer

基于视觉语义与激光点云交融构建的SLAM算法

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控制与决策 2024年第1期39卷 103-111页

作者：佟国峰杨宇航彭浩孟祥政殷旗君东北大学信息科学与工程学院沈阳110004

激光雷达作为同时定位与地图构建(SLAM)传感器之一,因精度高、性能稳定等特点而被广泛研究使用.但其获得的点云数据较稀疏,包含特征信息少,会导致误匹配、位姿估计误差大等问题,影响SLAM的定位和建图精度.对此,提出一种将视觉语义信息... 详细信息

激光雷达作为同时定位与地图构建(SLAM)传感器之一,因精度高、性能稳定等特点而被广泛研究使用.但其获得的点云数据较稀疏,包含特征信息少,会导致误匹配、位姿估计误差大等问题,影响SLAM的定位和建图精度.对此,提出一种将视觉语义信息与激光点云数据融合的SLAM算法(VSIL-SLAM).首先,基于投影思想将聚类后的点云映射到语义检测框内,生成语义物体,解决原始激光点云特征稀缺问题;然后,在形状特征的基础上引入拓扑特征对语义物体进行表述,提出基于匹配的拓扑相似性度量方法,解决单一特征造成的误匹配问题,提高匹配准确度;最后,加入语义物体点到点的几何约束,基于几何特征和语义物体构建前端里程计,并完成后端回环检测和位姿图优化设计.实验结果表明,所提出算法在定位和建图效果上都有显著提高,改善了激光SLAM算法的性能.

关键词：视觉语义信息点云聚类融合算法拓扑相似性度量前端里程计激光SLAM

海洋真菌Aspergillus sp.LW152抗细菌活性代谢产物研究

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中国抗生素杂志 2024年第6期49卷 627-633页

作者：刘仟茜王茹蔡磊殷军刘玲沈阳药科大学中药学院沈阳110016 中国科学院微生物研究所真菌学国家重点实验室北京100101 中国科学院大学北京100049

目的对海洋真菌Aspergillus sp.LW152发酵提取物的抗细菌成分进行研究。方法利用硅胶柱层析、葡聚糖凝胶Sephadex LH-20柱层析、半制备高效液相色谱等方法,对该菌株发酵提取物进行分离纯化;化合物结构通过核磁共振波谱(NMR)、质谱(MS)... 详细信息

目的对海洋真菌Aspergillus sp.LW152发酵提取物的抗细菌成分进行研究。方法利用硅胶柱层析、葡聚糖凝胶Sephadex LH-20柱层析、半制备高效液相色谱等方法,对该菌株发酵提取物进行分离纯化;化合物结构通过核磁共振波谱(NMR)、质谱(MS)等数据并与文献数据对比进行确定;采用微量肉汤稀释法对化合物抗菌活性进行体外评价。结果从真菌LW152发酵的乙酸乙酯提取物中分离得到了7个化合物,其结构分别鉴定为7-脱氧-7,14-二脱氢水杨酸(1)、7-脱氧-7,8-二脱氢水杨酸(2)、pseudaboydin B(3)、(Z)-5-(羟甲基)-2-(6'-甲基庚-2'-烯-2'-基)苯酚(4)、aspergillusene A(5)、2,4-二羟基-6-甲基苯甲酸甲酯(6)和1-亚油酸单甘油酯(7)。结论海洋真菌Aspergillussp.LW152能产生具有抗细菌活性的次级代谢产物,其中化合物4和5对6种致病细菌的生长均具有一定的抑制作用,化合物7对青枯雷尔菌的生长具有抑制作用。

关键词：海洋真菌曲霉属分离纯化结构鉴定次级代谢产物抗菌活性

沱沱河辫状河道多尺度形态特征及非活跃汊道的影响

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泥沙研究 2024年第1期49卷 38-44页

作者：何育聪李志威夏军强周银军武汉大学水资源工程与调度全国重点实验室湖北武汉430072 长江科学院湖北武汉430010

目前对长江源辫状河流的形态特征已有初步认识,但缺乏河段多尺度形态特征与非活跃汊道的影响研究。基于GEE和PyRIS,使用Landsat 8、Sentinel-2遥感影像、STRM V4地形数据和沱沱河站2013-2018年逐日流量数据,分析沱沱河多尺度的辫状平面... 详细信息

目前对长江源辫状河流的形态特征已有初步认识,但缺乏河段多尺度形态特征与非活跃汊道的影响研究。基于GEE和PyRIS,使用Landsat 8、Sentinel-2遥感影像、STRM V4地形数据和沱沱河站2013-2018年逐日流量数据,分析沱沱河多尺度的辫状平面形态特征及非活跃汊道的影响。结果表明:全河段平面形态呈宽窄相间的藕节状,且汊道随流量增大呈先增多后增宽的阶段性变化特征。子河段辫状强度与活动水域面积比呈先增后减的抛物线型变化规律,与水面展宽呈正幂律关系。非活跃汊道仍具有辫状河道的辫状强度特征,其地形较高,缺少漫滩机会,内部非活跃汊道形态稳定,年内摆幅小于10 m。

关键词：辫状河道形态特征非活跃河道日均流量遥感影像长江源