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Effects of water adsorption on active site-dependent H_(2)activation over MgO nanoflakes

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Nano Research 2023年第7期16卷 9059-9064页

作者： Aiyi Dong Kun Li Rentao Mu Conghui Liu Rongtan Li haoran jia Le Lin Qiang Fu School of Science Dalian Maritime UniversityDalian 116026China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Understanding the effect of H_(2)O adsorption on reactant activation is of great importance in heterogeneous catalysis,which remains a grand challenge particularly in oxide catalyst systems with structural ***,the effect of D_(2)O adsorption on D_(2)activation over MgO nanocatalysts at different temperatures has been investigated by transmission Fourier transform infrared(FT-IR)and temperature-programmed desorption(TPD).Two sets of hydride and hydroxyl species produced from D_(2)dissociation at more active and less active Mg-O pairs can be observed by FT-IR,which all desorb via the product of D_(2)as confirmed by TPD *** find that the physically adsorbed D_(2)O overlayer does not affect the dissociation of D_(2)since D_(2)may pass through the molecular layer and access the surface-active *** D_(2)O is partially dissociated on the MgO surface,D_(2)can only dissociate at the remaining active sites until that dissociated-ODw groups from D_(2)O occupy all active *** findings provide a fundamental understanding of the effect of water adsorption on D_(2)activation on oxide catalysts.

关键词： H_(2)activation MgO hydride hydroxyl H_(2)O

DNA methylation controlling abscisic acid catabolism responds to light to mediate strawberry fruit ripening

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Journal of Integrative Plant Biology 2024年第8期66卷 1718-1734页

作者： Yunfan Sun Xiaofang Yang Rongrong Wu Shouzheng Lv Yunduan Li haoran jia Yuying Yang Baijun Li Wenbo Chen Andrew C.Allan Guihua jiang Yan-Na Shi Kunsong Chen College of Agriculture&Biotechnology Zhejiang UniversityZijingang CampusHangzhou 310058China Institute of Horticulture Zhejiang Academy of Agricultural SciencesHangzhouZhejiang 310021China Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology Zhejiang UniversityZijingang CampusHangzhou 310058China The State Agriculture Ministry Laboratory of Horticultural Plant Growth Development and Quality ImprovementZhejiang UniversityZijingang CampusHangzhou 310058China New Zealand Institute for Plant&Food Research Limited Private Bag 92169AucklandNew Zealand School of Biological Sciences University of AucklandPrivate Bag 92019AucklandNew Zealand

Phytohormones,epigenetic regulation and environmental factors regulate fruit ripening but their interplay during strawberry fruit ripening remains to be *** this study,bagged strawberry fruit exhibited delayed ripening compared with fruit grown in normal light,correlating with reduced abscisic acid(ABA) *** of the key ABA catabolism gene,ABA 8′-hydroxylase FaCYP707A4,was induced in bagged *** light exclusion whole genome DNA methylation levels were up-regulated,corresponding to a delayed ripening process,while DNA methylation levels in the promoter of FaCYP707A4 were suppressed,correlating with increases in transcript and decreased ABA *** indicated FaCRY1,a blue light receptor repressed in bagged fruit and FaAGO4,a key protein involved in RNA-directed DNA methylation,could bind to the promoter of *** interaction between FaCRY1 and FaAGO4,and an increased enrichment of FaAGO4 directed to the FaCYP707A4 promoter in fruit grown under light suggests FaCRY1 may influence FaAGO4 to modulate the DNA methylation status of the FaCYP707A4 ***,transient overexpression of FaCRY1,or an increase in FaCRY1 transcription by blue light treatment,increases the methylation level of the FaCYP707A4 promoter,while transient RNA interference of FaCRY1 displayed opposite *** findings reveal a mechanism by which DNA methylation influences ABA catabolism,and participates in light-mediated strawberry ripening.

关键词： ABA catabolism DNA methylation light ripening strawberry

岩体裂隙的生态学意义研究：以河南省宜阳县锦屏山采石场为例

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环境科学与技术 2014年第9期37卷 48-54页

作者：贾昊冉宁立波李明陈娇中国地质大学环境学院湖北武汉430074

在高陡岩质边坡覆绿工程中,岩体裂隙有着非常重要的生态学意义。岩体裂隙可以截留和储存土壤、水分以及营养物质并保持稳定,同时导通水分和空气,构建出完整的适宜植物生长的地境。这对边坡的生态恢复具有较强的现实意义。文章在整合锦... 详细信息

在高陡岩质边坡覆绿工程中,岩体裂隙有着非常重要的生态学意义。岩体裂隙可以截留和储存土壤、水分以及营养物质并保持稳定,同时导通水分和空气,构建出完整的适宜植物生长的地境。这对边坡的生态恢复具有较强的现实意义。文章在整合锦屏山高陡岩质边坡进行岩体裂隙调查结果的基础上,依据生态地质学理论,通过对岩体裂隙空间、裂隙的优势方向、裂隙的连通性以及裂隙内的温湿度条件等当地岩体裂隙特点进行分析,得出如下结论:良好的裂隙条件可以满足植物生长所需的地境条件要求,为人工构建地境提供了有利的条件和理论依据。通过对岩体裂隙的有效利用,能够使复绿工作种植的植物长期稳定的生长,从而帮助生态环境向可自我调节的方向发展。

关键词：岩体裂隙生态学地境锦屏山

Evaluation of the therapeutic significance of Glehniae Radix polysaccharides on the ulcerative colitis through DSS-induced rat model

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Food Science and Human Wellness 2025年

作者： Jie Liu Xufang Geng Yuxin Yang jiao Xu haoran Feng Tianshuo Zhang Guangzhao Zhou Man Wang Changshun Wang Dongsheng jia Yuting Chen Bin Cong Ding Zhao The Postdoctoral Mobile Station of Basic Medicine， Hebei Medical University The Department of Pharmacognosy， School of Pharmacy， Hebei Medical University Hebei Key Laboratory of Forensic Medicine， College of Forensic Medicine， Hebei Medical University

Glehniae Radix has a wide range of pharmaceutical applications， and research on its main components has mainly focused on coumarins， alkaloids， lignans， and flavonoids， while neglecting the research on polysaccharides. Literature reports and our previous studies have shown that polysaccharides have certain therapeutic significance in immune regulation， antioxidant， anti-inflammatory and other aspects. Herein， the rat model of ulcerative colitis (UC) was established to evaluate the anti-inflammatory efficacy of the prepared Glehniae Radix polysaccharide (GLP) from the perspectives of inflammatory factors， intestinal tissue morphology， and microflora changes. The polysaccharides are mainly composed of galacturonic acid， rhamnose， glucose， galactose， and arabinose in molar ratios of 1.4:9.2:33.3:2.5:2.9， and GLP could downregulate the expression pro-inflammatory factors (interleukin-6， tumor necrosis factor-α， and interferon-γ) and significantly upregulate the expression of anti-inflammatory factor (interleukin-10). In addition， Glehniae Radix aqueous extract (GLA)， GLP with low dosage (GLPL) and GLP with high dosage (GLPH) could increase the number of goblet cells， enhance the integrity of crypt structure， and reverse the status of inflammatory infiltrating cells. Moreover， GLA and GLPH could upregulate Lactobacillus and Lachnoclostridium in UC rats， and appropriately downregulate Lachnospiraceae＿NK4A136＿group， thereby optimizing the proportion of bacterial flora and improving the intestinal microbial environment. Our findings not only be valuable as theoretical materials for the further clinical applications of GLP， but the identified biomarkers and metabolic pathways also provide new clues for the diagnosis of UC.

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嘧草醚在水稻中的残留消解动态及膳食风险评估

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环境科学学报 2020年第4期40卷 1491-1499页

作者：贾浩然张月李卫李保同周雯雯江西农业大学国土资源与环境学院南昌330045 江西农业大学食品科学与工程学院南昌330045

为了评价嘧草醚在水稻生长过程中使用的安全性,于2018-2019年分别在佳木斯、济宁、南昌、宁波4地进行了为期2年的田间试验,研究了嘧草醚在田水、土壤、稻株中的消解动态及稻米、稻壳、稻杆中的最终残留.结果表明:嘧草醚在田水、土壤及... 详细信息

为了评价嘧草醚在水稻生长过程中使用的安全性,于2018-2019年分别在佳木斯、济宁、南昌、宁波4地进行了为期2年的田间试验,研究了嘧草醚在田水、土壤、稻株中的消解动态及稻米、稻壳、稻杆中的最终残留.结果表明:嘧草醚在田水、土壤及稻株中的消解规律均符合一级动力学模型,在4地田水中的消解半衰期(t1/2)为1.07~3.48 d,土壤中的消解半衰期(t1/2)为3.14~5.42 d,稻株中的消解半衰期(t1/2)为4.47~8.08 d.通过对消解半衰期与土壤性质和气候条件的线性回归分析可得,嘧草醚在不同基质中的消解速率均与土壤有机质含量和平均气温呈显著相关.施用1.5倍或2倍推荐使用剂量的嘧草醚后(90或120 g·hm^-2),收获的稻米籽实中检测出嘧草醚的残留量均未超过日本和韩国规定的最大残留限量(MRL)值(0.05 mg·kg^-1).通过计算得出每人每天从稻米中所摄入的嘧草醚为0.0037 mg,其风险商值(RQ)为0.0028,处于安全水平.

关键词：嘧草醚水稻消解动态残留水平

Comparative analysis of fruit firmness and genes associated with cell wall metabolisms in three cultivated strawberries during ripening and postharvest

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Food Quality and Safety 2023年第3期7卷 516-524页

作者：任奕博李柏君贾浩然杨肖芳孙云帆寿佳涵蒋桂华石艳娜陈昆松 College of Agriculture and Biotechnology Zhejiang UniversityZijingang CampusHangzhouChina Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology Zhejiang UniversityZijingang CampusHangzhouChina State Agriculture Ministry Laboratory of Horticultural Plant Growth Development and Quality ImprovementZhejiang UniversityZijingang CampusHangzhouChina Institute of Horticulture Zhejiang Academy of Agricultural SciencesHangzhouChina

Cultivated strawberry(Fragaria×ananassa),a world-famous fruit,is subjected to rapid softening during ripening,resulting in a shorter shelf life and severe economic losses during storage and ***,there is limited understanding of the molecular mechanism underlying differences in fruit firmness during ripening and postharvest among cultivated ***,we explored this molecular mechanism by comparing three cultivated strawberries via firmness measurement,transcriptome analysis,quantitative real-time polymerase chain reaction,and correlation analysis,and revealed FaEXP7,FaPG2,FaPLA,and Faβ-Gal4 as potential softening activators expressed before harvest to determine fruit with more softened texture and shorter shelf life,and that extremely high expression levels of FaCEL1-1 and FaCEL1-3 during ripening might be accelerators to intensify this ***,both the enzyme activities of FaCEL and the expression pattern of FaCEL1-3 showed a significantly negative correlation with fruit firmness after harvest,suggesting that FaCEL1-3 might play a key role in promoting strawberry fruit softening not only during ripening but also *** results showed that the difference in fruit firmness and shelf life among cultivated strawberries was controlled by the temporal expression pattern of a legion of cell wall-associated genes during ripening and postharvest.

关键词： Fragaria×ananassa fruit cell wall softening ripening postharvest

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基于云模型的盾构隧道开挖面稳定性评价

北京交通大学学报 2019年第3期43卷 43-49页

作者：刘敦文贾昊燃周唱晓贡永志刘则悦中南大学资源与安全工程学院长沙410083 衡阳市城市建设投资有限公司湖南衡阳421000

随着国内盾构开挖技术的不断成熟,各大型盾构隧道相继建成,与此同时盾构施工中所遇到的各类安全性问题也日益凸显.因此,基于过江隧道盾构掘进时由于开挖面的不稳定造成的安全隐患问题,针对衡阳湘江隧道盾构开挖施工区段岩溶-侵蚀耦合作... 详细信息

随着国内盾构开挖技术的不断成熟,各大型盾构隧道相继建成,与此同时盾构施工中所遇到的各类安全性问题也日益凸显.因此,基于过江隧道盾构掘进时由于开挖面的不稳定造成的安全隐患问题,针对衡阳湘江隧道盾构开挖施工区段岩溶-侵蚀耦合作用下的特殊地形,提出了一种基于云模型理论的盾构隧道安全评价方法;建立了一套盾构隧道开挖面稳定性的评价因素体系,并通过云模型算法得出综合评价数字特征并生成云滴图.结果表明:基于云模型的安全评价方法可以量化开挖面稳定性评价的定性评价标准;采用云模型的评价方法能降低评价标准的主观性,在现有规范的基础上,能为隧道施工过程解决开挖面稳定性提供一定的对策和参考.

关键词：盾构施工开挖面稳定云模型岩溶-侵蚀地质

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20%辛酸乳油对非耕地杂草的田间防效

植物保护 2020年第1期46卷 285-288页

作者：李卫张月贾浩然李保同石绪根江西农业大学国土资源与环境学院

采用茎叶喷雾法测定了20%辛酸EC 3.6、10.8、32.4、48.6、64.8和97.2 kg/hm 2(有效成分,下同)对非耕地杂草的防除效果。结果表明,20%辛酸EC 64.8~97.2 kg/hm 2处理药后7 d对总草株防效为86.98%~95.65%,药后15 d鲜重防效为85.40%~94.86%... 详细信息

采用茎叶喷雾法测定了20%辛酸EC 3.6、10.8、32.4、48.6、64.8和97.2 kg/hm 2(有效成分,下同)对非耕地杂草的防除效果。结果表明,20%辛酸EC 64.8~97.2 kg/hm 2处理药后7 d对总草株防效为86.98%~95.65%,药后15 d鲜重防效为85.40%~94.86%,显著高于对照药剂41.7%草甘膦AS 1.0 kg/hm 2处理,与对照药剂20%百草枯AS 0.6 kg/hm 2处理相近;20%辛酸EC 3.6~32.4 kg/hm 2处理药后7 d对总草株防效及药后15 d鲜重防效均低于或显著低于对照药剂41.7%草甘膦AS 1.0 kg/hm 2处理和20%百草枯AS 0.6 kg/hm 2处理。20%辛酸EC可有效地控制非耕地杂草,推荐使用剂量为64.8~97.2 kg/hm 2。

关键词：杂草防除辛酸非耕地

基于虚拟现实技术的隧道火灾应急培训系统构建和研究

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中国安全生产科学技术 2019年第2期15卷 131-137页

作者：刘敦文贾昊燃翦英骅邱丰恺颜辉中南大学资源与安全工程学院湖南长沙410083 中南大学安全理论创新与促进研究中心湖南长沙410083 衡阳市城市建设投资有限公司湖南衡阳421000

为了解决现实中隧道火灾应急救援演练成本高、危险性大、适应能力弱的问题,基于建构主义安全培训理论,以3Dmax和Unity3D为技术手段,构建隧道火灾应急救援培训系统。系统功能下设体验模式、训练模式和底层模式,对应开发6个培训模块和15... 详细信息

为了解决现实中隧道火灾应急救援演练成本高、危险性大、适应能力弱的问题,基于建构主义安全培训理论,以3Dmax和Unity3D为技术手段,构建隧道火灾应急救援培训系统。系统功能下设体验模式、训练模式和底层模式,对应开发6个培训模块和15个场景科目,实现在高沉浸性的虚拟环境中对隧道救援人员、管理人员进行火灾应急培训。研究结果表明:该系统可以提高人员参加应急救援演练的积极性,降低应急演练成本,使学员在安全真实的虚拟环境中熟悉救援设备使用方法,增强学员处理事故场景的能力。

关键词：建构主义应急救援火灾虚拟现实培训系统