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VPD modifies CO_(2) fertilization effect on tomato plants via abscisic acid and jasmonic acid signaling pathways
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作者 Dalong Zhang Huihua Yang +5 位作者 xiaolu chen Yan Li Yunzhou Li Hongye Liu Xulin Wu Min Wei 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第5期1165-1176,共12页
Atmospheric CO_(2)concentration is elevated globally,which has“CO_(2)fertilization effects”and potentially improves plant photosynthesis,yield,and productivity.Despite the beneficial effect of CO_(2)fertilization be... Atmospheric CO_(2)concentration is elevated globally,which has“CO_(2)fertilization effects”and potentially improves plant photosynthesis,yield,and productivity.Despite the beneficial effect of CO_(2)fertilization being modulated by vapor pressure deficit(VPD),the underlying mechanism is highly uncertain.In the present study,the potential roles of hormones in determining CO_(2)fertilization effects under contrasting high and low VPD conditions were investigated by integrated physiological and transcriptomic analyses.Beneficial CO_(2)fertilization effects were offset under high VPD conditions and were constrained by plant water stress and photosynthetic CO_(2)utilization.High VPD induced a large passive water driving force,which disrupted the water balance and consequently caused plant water deficit.Leaf water potential,turgor pressure,and hydraulic conductance declined under high VPD stress.The physiological evidence combined with transcriptomic analyses demonstrated that abscisic acid(ABA)and jasmonic acid(JA)potentially acted as drought-signaling molecules in response to high VPD stress.Increased foliar ABA and JA content triggered stomatal closure to prevent excessive water loss under high VPD stress,which simultaneously increased the diffusion resistance for CO_(2)uptake from atmosphere to leaf intercellular space.High VPD also significantly increased mesophyll resistance for CO_(2)transport from stomatal cavity to fixation site inside chloroplast.The chloroplast“sink”CO_(2)availability was constrained by stomatal and mesophyll resistance under high VPD stress,despite the atmospheric“source”CO_(2)concentration being elevated.Thus,ABA-and JA-mediated drought-resistant mechanisms potentially modified the beneficial effect of CO_(2)fertilization on photosynthesis,plant growth,and yield productivity.This study provides valuable information for improving the utilization efficiency of CO_(2)fertilization and a better understanding of the physiological processes. 展开更多
关键词 Abscisic acid CO_(2) fertilization Jasmonic acid Mesophyll conductance Stomatal conductance Vapor pressure deficit
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Morphological Development of Sambong (Blumea balsamifera (L.) DC.) Leaf Studied by Frozen Section and Thin Section
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作者 Liwei Liu xiaolu chen +1 位作者 Quan Yang Yuxin Pang 《Journal of Biosciences and Medicines》 2016年第4期10-13,共4页
The sambong (Blumea balsamifera (L.) DC.) leaf was investigated by applying frozen section and thin section technology, and observed through optical microscope. The results showed that the sambong leaf was firstly ori... The sambong (Blumea balsamifera (L.) DC.) leaf was investigated by applying frozen section and thin section technology, and observed through optical microscope. The results showed that the sambong leaf was firstly originated nearby the apical bud at the stem tip. The first leaf grows fast, that the mitosis happens frequently and the cytoplasm manufacture rapidly. The cells in the first few leaves have not yet differentiated into the spongy parenchyma and palisade parenchyma. In the mature leaf, the spongy parenchyma and palisade parenchyma were fully developed. The epidermal hairs were firstly developed on the abaxial side of the first leaf. 展开更多
关键词 Sambong Blumea balsamifera Ainaxiang Nalong Morphological Development Thin Section
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The Biomass Dosage Influences the Effects of Diethyl Aminoethyl Hexanoate on Micropropagation of Echinacea purpurea (L.) Moench
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作者 xiaolu chen Dongliang Li +3 位作者 Junjie Zhang Qingling Li Yuesheng Yang Hong Wu 《Journal of Biosciences and Medicines》 2016年第12期97-110,共15页
The plant growth regulator diethyl aminoethyl hexanoate (DA-6) has proved highly effective on micropropagation of the medicinal plant purple coneflower (Echinacea purpurea (L.) Moench), however, sharp variation of the... The plant growth regulator diethyl aminoethyl hexanoate (DA-6) has proved highly effective on micropropagation of the medicinal plant purple coneflower (Echinacea purpurea (L.) Moench), however, sharp variation of the effects existed among explants in the same treatment, making the application of DA-6 in micropropagation difficult. In order to clarify factors that influencing the treating results of DA-6, explants with different biomass dosage were prepared and inoculated onto medium supplemented with different concentrations of DA-6. It was found that among the three kinds of biomass dosage explants, the lowest biomass explants required the lowest concentration of DA-6, and the highest biomass explants required the highest concentration of DA-6 for the best results on adventitious buds regeneration. Similar results were obtained when regenerated buds of three different biomass dosages were cultured. It could be concluded from the above experimental results that for achieving better DA-6 application results, the concentration of DA-6 should be determined not only by the types but also by the biomass dosage of the explants. The present finding might help to improve the micropropagation efficiency in E. purpurea, and might be applicable for other species 展开更多
关键词 Plant Growth Regulator DA-6 MICROPROPAGATION Biomass Dosage Echinacea purpurea
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Microscopic Structural Comparison between Epidermal Trichomes in Blumea balsamifera (L.) DC. and Blumea laciniata (Roxb.) DC
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作者 xiaolu chen Yingbo Zhang +1 位作者 Yuxin Pang Qian Jiang 《Journal of Biosciences and Medicines》 2016年第12期70-75,共6页
Immature leaves and stems, which were about one to three centimeters nearby the stem tips, of Blumea balsamifera (L.) DC. (BB) and Blumea laciniata (Roxb.) DC. (BL) were cut into sections under ?18?C with a frozen sec... Immature leaves and stems, which were about one to three centimeters nearby the stem tips, of Blumea balsamifera (L.) DC. (BB) and Blumea laciniata (Roxb.) DC. (BL) were cut into sections under ?18?C with a frozen section machine, and observed under an optical microscope. Results show that the most significant difference is that the BB has only one kind of glandular trichomes, while the BL has two. The glandular trichomes found on BB terms were all short glandular hairs (SGH), which were not longer than 100 μm. On BL stems, besides the SGH, the long glandular hairs (LGH), which were longer than 200 μm, were also found. By the factors pointed out in present study, the BB and BL and be distinguished from each other. 展开更多
关键词 Blumea balsamifera Blumea laciniata Sambong Ainaxiang Glandular Hair
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Anther Culture and Plant Regeneration of Tetraploid Purple Coneflower (Echinacea purpurea L.)
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作者 xiaolu chen Dahanayake Nilanthi +1 位作者 Yuesheng Yang Hong Wu 《Journal of Biosciences and Medicines》 2016年第12期89-96,共8页
Anthersisolated from tetraploid purple coneflowerplants were cultured in vitro. The highest callus induction rate was obtained when the medium was consisted of N6 basal elements, 4% sucrose, 0.5 mg?L?1 BA, and 0.10 mg... Anthersisolated from tetraploid purple coneflowerplants were cultured in vitro. The highest callus induction rate was obtained when the medium was consisted of N6 basal elements, 4% sucrose, 0.5 mg?L?1 BA, and 0.10 mg?L?1 NAA. Various morphogenesis such as globular, heart-shape, torpedo-shapeand final state embryos as well asvarious texture calluses around were observed. Out of 110 plantlets regenerated, 104 were confirmed as diploid and the rest were as tetraploid. Plants of one diploid offspring strain presented aspecialcharacter in pot: unlike the original tetraploid plants, it grown tubular, bisexual ray florets. The results obtained in the present studies indicated that although the tetraploid purple coneflower plants produced only diploid microspores, the recovery of some useful mutants through in vitro anther cultures might be reasonably expected. 展开更多
关键词 Purple Coneflower Echinacea purpurea Anther Culture TETRAPLOID
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Mannitol and Sorbitol Improve Uniformity of Adventitious Shoots Regeneration in Echinacea purpurea L. Moench
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作者 xiaolu chen Dongliang Li +1 位作者 Yuesheng Yang Hong Wu 《Journal of Biomedical Science and Engineering》 2016年第10期58-64,共7页
Mannitol or sorbitol was added into the Murashige and Skoog (MS) medium contain-ing certain concentrations of 6-Benzyladenine (BA) which was used to induce adventi-tious buds of Echinacea purpurea L. Results showed th... Mannitol or sorbitol was added into the Murashige and Skoog (MS) medium contain-ing certain concentrations of 6-Benzyladenine (BA) which was used to induce adventi-tious buds of Echinacea purpurea L. Results showed that the induced adventitious buds growing from medium added with 15 g·L-1 mannitol or sorbitol of the same con-centration were more consistent in height. The regeneration rates in MS medium containing 0.2 mg·L-1 BA and 15 g·L-1 mannitol were increased, while in MS medium containing 0.2 and 0.5 mg·L-1 BA, and 15 g·L-1 sorbitol, the regeneration rates were suppressed. On the other hand, genotype of explants and the concentration of BA in-fluenced the incidence of hyperhydricity, and the hyperhydricity of regenerated buds was more severe when the petiole explants were inoculated on medium with 15 g·L-1 mannitol or 15 g·L-1 sorbitol. The present study offers new possibility to the production of uniform plantlets for commercial cultivation in this important medicinal plant. 展开更多
关键词 Echinacea purpurea MICROPROPAGATION Tissue Culture MANNITOL SORBITOL Osmotic Pressure
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Analysis of Volatile Components in Fresh Fruit of Morinda citrifolia L.from Different Origins Based on HS-SPME-GC/MS 被引量:1
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作者 Dan WANG Qian JIANG +5 位作者 Qinglong WANG Chao YUAN Maoyuan WANG Zuowang FAN xiaolu chen Fulai YU 《Agricultural Biotechnology》 CAS 2022年第4期107-112,共6页
[Objectives]This study was conducted to clarify the differences of volatile components in fresh fruit of Morinda citrifolia L.from different origins.[Methods]The method of HS-SPME-GC/MS detection was used to determine... [Objectives]This study was conducted to clarify the differences of volatile components in fresh fruit of Morinda citrifolia L.from different origins.[Methods]The method of HS-SPME-GC/MS detection was used to determine the volatile chemical components in fresh fruit of M.citrifolia.[Results]52,52 and 45 volatile components were identified from the fresh fruit of M.citrifolia from Xisha,Wanning and Haikou,respectively.Among them,the number and content of the identified esters were relatively high,mainly methyl caprylate,ethyl caprylate,4-pentenyl caproate,3-methylbuten-2-enyl caprylate,methyl caproate,and ethyl caproate.There were also fatty acids,alcohols,phenols,ketones,aldehydes and other substances.There were 33 common ingredients in the fruit from the three origins,mainly including caprylic acid,caproic acid,capric acid,methyl caprylate,ethyl caprylate,4-pentenyl caproate,3-methylbutene-2-enyl caprylate,methyl caproate,ethyl caproate,methyl caprate and hexyl caproate.[Conclusions]The types and contents of volatile components in fresh fruit of M.citrifolia from different origins were significantly different. 展开更多
关键词 Morinda citrifolia L. Fresh fruit Different origins Volatile chemical components GC-MS
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Design and verification of a satellite-terrestrial integrated IP network model for the Global Energy Interconnection 被引量:2
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作者 Yun Liang Yao Wang +3 位作者 Li Huang Jun Ma xiaolu chen Jingtao Huang 《Global Energy Interconnection》 2019年第6期497-504,共8页
In order to meet the pressing demand for wide-area communication required by the Global Energy Interconnection(GEI),accelerating the construction of satellite-terrestrial Integra怕d networks that can achieve network e... In order to meet the pressing demand for wide-area communication required by the Global Energy Interconnection(GEI),accelerating the construction of satellite-terrestrial Integra怕d networks that can achieve network extension and seamless global coverage has become the focus of power communication tech no logy development.In this study,we propose a satellite-terrestrial integrated network model that can support interconnection and interoperation on the IP layer between the satellite system and the怕rrestrial segment of the existing power communication system.First,the composition and function of the satellite-terrestrial collaborative network are explained.Then,the IP-based protocol stack is described,and a typical applicati on experime nt is con ducted to illustrate the particular process of this protocol stack.Fin ally,a use case of IP interconn ection that depends on GEO satellite communication is detailed.The experime ntal study has showed that the satellite-terrestrial collaborative network can efficiently support various IP applications for the GEI. 展开更多
关键词 Global Energy Interconnection(GEI) Satellite-terrestrial integrated network IP network
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The Effect of Magnesium on Accumulations of Primary Metabolites and Yield of Blumea balsamifera
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作者 Dan WANG Huiping LAN +4 位作者 Yingbo ZHANG Xuan HU xiaolu chen Yuxin PANG Fulai YU 《Agricultural Biotechnology》 CAS 2020年第4期56-59,67,共5页
[Objectives]This study was conducted to investigate the effects of magnesium on the yield of Blumea balsamifera(L.)DC.and the accumulation of primary metabolites that affect yield of the medicinal material.[Methods]Th... [Objectives]This study was conducted to investigate the effects of magnesium on the yield of Blumea balsamifera(L.)DC.and the accumulation of primary metabolites that affect yield of the medicinal material.[Methods]The annual seedlings of B.balsamifera were selected as experimental materials.The treatment concentrations of magnesium(Mg)were set as 0,1.5,15 and 150 mg/ml supplied by MgSO4·7H2O.The yield of the medicinal material was measured dynamically.And the content of total sugar was determined by 3,5-dinitrosalicylic acid colorimetry;the content of crude protein was determined by the Kjeldahl method;the ash content was determined by the high-temperature burning method;the crude fat content was determined with a crude fat instrument;and the crude fiber content was determined by the acid-base washing and weighing method.[Results]Mg significantly increased the yield of B.balsamifera medicinal material,especially 15 mg/ml Mg.It was found that in September,October and November,1.5 mg/ml and 15 mg/ml Mg significantly increased the contents of primary metabolites including total sugar,ash,crude protein,crude fat and crude fiber,and 150 mg/ml of Mg increased the accumulation of total sugar,ash,crude protein and crude fiber to different degrees,but had certain inhibitory effect on the accumulation of crude fat.In December,the application of Mg inhibited the accumulation of total sugar,ash and crude protein to different degrees,but significantly promoted the accumulation of crude fat and fiber.[Conclusions]This study provides a theoretical basis for clarifying the effects of different concentrations of magnesium on plant growth. 展开更多
关键词 Magnesium(Mg) Blumea balsamifera YIELD Primary metabolites Total sugar ASH Crude protein
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Visibility graph approach to extreme event series
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作者 张晶 陈晓露 +2 位作者 王海英 顾长贵 杨会杰 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期317-327,共11页
An extreme event may lead to serious disaster to a complex system.In an extreme event series there exist generally non-trivial patterns covering different time scales.Investigations on extreme events are currently bas... An extreme event may lead to serious disaster to a complex system.In an extreme event series there exist generally non-trivial patterns covering different time scales.Investigations on extreme events are currently based upon statistics,where the patterns are merged into averages.In this paper from extreme event series we constructed extreme value series and extreme interval series.And the visibility graph is then adopted to display the patterns formed by the increases/decreases of extreme value or interval faster/slower than the linear ones.For the fractional Brownian motions,the properties for the constructed networks are the persistence,threshold,and event-type-independent,e.g.,the degree distributions decay exponentially with almost identical speeds,the nodes cluster into modular structures with large and similar modularity degrees,and each specific network has a perfect hierarchical structure.For the volatilities of four stock markets(NSDQ,SZI,FTSE100,and HSI),the properties for the former three's networks are threshold-and market-independent.Comparing with the factional Brownian motions,their degree distributions decay exponentially but with slower speeds,their modularity behaviors are significant but with smaller modularity degrees.The fourth market behaves similar qualitatively but different quantitatively with the three markets.Interestingly,all the transition frequency networks share an identical backbone composed of nine edges and the linked graphlets.The universal behaviors give us a framework to describe extreme events from the viewpoint of network. 展开更多
关键词 extreme events visibility graph
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艾纳香内生真菌粉红粘帚霉抗菌次生代谢产物 被引量:7
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作者 舒雪纯 张影波 +5 位作者 官玲亮 陈振夏 黄梅 陈晓鹭 袁媛 元超 《生物工程学报》 CAS CSCD 北大核心 2020年第8期1650-1658,共9页
植物内生真菌一直是发现结构新颖、活性广泛的化合物的重要宝库。文中对一株艾纳香内生真菌粉红粘帚霉Clonostachysrosea进行化学研究,通过活性跟踪手段,结合硅胶柱色谱、凝胶色谱、以及半制备液相色谱技术从该菌株的发酵提取物中共分... 植物内生真菌一直是发现结构新颖、活性广泛的化合物的重要宝库。文中对一株艾纳香内生真菌粉红粘帚霉Clonostachysrosea进行化学研究,通过活性跟踪手段,结合硅胶柱色谱、凝胶色谱、以及半制备液相色谱技术从该菌株的发酵提取物中共分离获得6个单体化合物,经波谱学技术结合质谱鉴定其分别为verticillin A(1)、(S)-(+)-fusarinolic acid(2)、8-hydroxyfusaric acid(3)、cerebroside C(4)、3-Maleimide-5-oxime(5)以及bionectriol A(6)。所有化合物进行了体外抗大肠埃希菌、金黄色葡萄球菌、枯草芽孢杆菌以及铜绿假单胞菌4株细菌的活性评价,其中1、4和6对3株细菌表现出显著的抑菌活性,MIC值2-16μg/mL。研究结果为从黎药植物艾纳香的内生真菌中寻找新型抗生素提供重要参考。 展开更多
关键词 艾纳香 内生真菌 次生代谢产物 抗菌活性
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热性感染相关性癫痫综合征患儿的临床及随访分析
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作者 邓瑶 喻韬 +1 位作者 陈小璐 罗蓉 《中华妇幼临床医学杂志(电子版)》 CAS 2022年第6期645-651,共7页
目的探讨热性感染相关性癫痫综合征(FIRES)患儿的临床表现、脑电图及医学影像学特点。方法选择2016年8月至2019年9月,于四川大学华西第二医院诊治的5例FIRES患儿(患儿1~5)为研究对象。回顾性分析其临床病例资料,包括临床表现与实验室检... 目的探讨热性感染相关性癫痫综合征(FIRES)患儿的临床表现、脑电图及医学影像学特点。方法选择2016年8月至2019年9月,于四川大学华西第二医院诊治的5例FIRES患儿(患儿1~5)为研究对象。回顾性分析其临床病例资料,包括临床表现与实验室检查、脑电图及医学影像学检查、治疗和随访结果等。本研究遵循的程序符合2013年新修订的《世界医学协会赫尔辛基宣言》要求。结果本研究患儿1~5的研究结果如下。①一般临床资料:年龄为4~9岁,男性与女性患儿比为2∶3,发热至首次抽搐发作间隔时间为4~7 d,入院时均处于昏迷状态,改良Glasgow昏迷评分为3~7分。②脑电图检查结果:其脑电图背景节律呈慢化、多灶性癫痫样放电。③医学影像学检查结果:其病程早期头颅影像学检查结果正常,后期均可见脑萎缩改变,在额、顶、枕叶皮质或皮质下及脑室旁白质区等部位出现异常信号影。④治疗结果:对其采取多种抗癫痫药物、激素、丙种球蛋白、血浆置换等治疗均无效;采用生酮饮食(KD)治疗1~14 d后,其抽搐发作频率降低。⑤随访结果:在随访1~6个月时,2例(患儿3、5)癫痫发作得到完全控制,1例(患儿1)癫痫发作得到明显控制,2例(患儿2、4)遗留难治性癫痫发作;除1例(患儿3)仅伴轻度学习障碍外,其余4例(患儿1~2、4~5)均存在中至重度认知障碍。结论FIRES是一种严重癫痫性脑病,多数FIRES患儿经治疗后,可遗留严重认知功能损害和难治性癫痫发作,预后差,接受药物治疗如常规抗癫痫药物、麻醉剂、免疫调节等效果不理想,KD治疗可能有助于控制癫痫发作。 展开更多
关键词 热性感染相关性癫痫综合征 难治性癫痫 生酮饮食 抗惊厥药 抽搐 发育障碍 儿童
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Effect of volatile oil from Blumea Balsamifera(L.) DC. leaves on wound healing in mice 被引量:2
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作者 Yuxin Pang Dan Wang +5 位作者 Xuan Hu Hui Wang Wanjin Fu Zuowang Fan xiaolu chen Fulai Yu 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2014年第6期716-724,共9页
OBJECTIVE: To assess the effectiveness of violateoil from Blumea Balsamifera(L.) DC. leaves(BB oil)on wound healing in mice.METHODS: Undiluted BB oil and its diluted solutions with olive oil to 1/5 and 1/10 to yield B... OBJECTIVE: To assess the effectiveness of violateoil from Blumea Balsamifera(L.) DC. leaves(BB oil)on wound healing in mice.METHODS: Undiluted BB oil and its diluted solutions with olive oil to 1/5 and 1/10 to yield BB oil1/5and BB oil1/10 were applied to the wounded skin before wound healing conditions were assessed by healing rate, histopathology, and contents of collagen, hydroxyproline, and Neuropeptide Substance P(SP). All above results were compared with the efficacies of the control, pure olive oil, basic fibroblast growth factor(BFGF), and cream of Jing Wan Hong(JWH).RESULTS: BB oil1/5and BB oil1/10 improved wound contraction and closure. Histopathology study further confirmed a desirable histological organization of wound tissues. BB oil1/5and BB oil1/10 reduced the number of inflammatory cells, increased wound-healing rates, and significantly increased the hydroxyproline content. Both BB oil1/5and BB oil1/10 improved formation of collagen, and reduced the frequency of fibroblasts. Moreover, BB oil1/5and BB oil1/10 markedly promoted SP expression. However, undiluted BB oil may induce skin thickening and hardening, inhibite collagen synthesis and delay complete skin wound healing.CONCLUSION: The BB oil1/5and BB oil1/10 promoted capillary regeneration, blood circulation, collagen deposition, granular tissue formation, epithelial deposition, and wound contraction. The mechanism underlying the action might be related to induction of SP secretion, and the proliferation and differentiation of mesenchymal cells. 展开更多
关键词 WoundBlumea Balsamifera (L.)cumhealing NEUROPEPTIDES DC. Borneolum Synthciticum
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Synergetic effect of polydopamine particles and in-situ fabricated gold nanoparticles on charge-dependent catalytic behaviors
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作者 Xia Han xiaolu chen +1 位作者 Mengfei Yan Honglai Liu 《Particuology》 SCIE EI CAS CSCD 2019年第3期63-70,共8页
The versatile catechol unit of polydopamine (PDA) endows this molecule with a broad ranging adhesive properties and reducibility.We prepared free-standing PDA particles by a simple self-polymerization and these partic... The versatile catechol unit of polydopamine (PDA) endows this molecule with a broad ranging adhesive properties and reducibility.We prepared free-standing PDA particles by a simple self-polymerization and these particles served as both an effective reductant and scaffold for a hybrid catalyst.The raspberrylike nanocomposites featured a high density of AuNPs uniformly deposited on PDA particles (PDA@Au).This system was prepared in-situ with assistance from the active catechol and amine groups of the PDA particles.To quantify the effect of the PDA carriers,we studied the catalytic activity of the PDA and PDA@Au particles.The PDA particles showed a pronounced charge-dependent catalytic activity for reduction of cationic methylene blue,negatively-charged 4-nitrophenolate,and zwitterionic rhodamine B in the presence of borohydride,whereas PDA@AuNPs showed catalytic activity with a less pronounced charge-dependence of the catalytic efficiency of the AuNPs.The PDA particles served as a redox mediator and adsorbent accelerator in degradation of the dyes owing to its unique chemical structure. 展开更多
关键词 Poiydopamine Gold NANOPARTICLE Hybrid catalyst ADSORBENT Redox MEDIATOR
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Theoretical investigation on the elusive biomimetic iron(Ⅲ)-iodosylarene chemistry: An unusual hydride transfer triggers the Ritter reaction
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作者 Lanping Gao xiaolu chen +4 位作者 Dongru Sun Hua Zhao Yufen Zhao Wonwoo Nam Yong Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第12期3857-3861,共5页
Introduction of iodosylarnes into biomimetic nonheme chemistry has made great achievement on identification of the subtle metal-oxygen reaction intermediates. However, after more than three decades of experimental and... Introduction of iodosylarnes into biomimetic nonheme chemistry has made great achievement on identification of the subtle metal-oxygen reaction intermediates. However, after more than three decades of experimental and theoretical efforts the nature of the metal-iodosylarene adducts and the related dichotomous one-oxidant/multiple-oxident controversy have remained a matter of speculation. Herein, we report a theoretical study of the structure-activity relationship of the noted iron(Ⅲ)-iodsylarene complex,FeⅢ(Ph IO)(OTf)3(1), in oxygenation of cyclohexene. The calculated results revealed that 1 behaves like a chameleon by adapting its roles as a 2 e-oxidant or an oxygen donor, as a response to the regioselective attack of the C–H bond and the C=C bond. The oxidative C–H bond activation by 1 was found, for the first time, to proceed via a novel hydride transfer process to form a cyclohexene carbonium intermediate,such non-rebound step triggers the Ritter reaction to uptake an acetonitrile molecule to form the amide product, or proceeds with the rebound of the hydroxyl group return to the solvent cage to form the hydroxylated product. While in the C=C bond activation, 1 is a normal oxygen donor and shows two-state reactivity to present the epoxide product via a direct oxygen atom transfer mechanism. These mechanistic findings fit and explain the famous Valentine’s experiments and enrich the non-rebound scenario in bioinorganic chemistry. 展开更多
关键词 Reaction mechanism DFT calculations Metal-iodosylbenzene Ritter reaction Olefin oxidation
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Multi-ratio optical thermometry and energy storage characteristics of Yb^(3+)/Er^(3+)/Tm^(3+)doped BaNb_(2)O_(6)transparent glass-ceramics
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作者 Junhao Xing Feng Luo +6 位作者 Yaoyi Qin xiaolu chen Yingying Liang Zhixin Gao Fei Shang Huarui Xu Guohua chen 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第7期138-148,共11页
In order to meet the needs of new materials gradually developing towards miniaturization,integration,and light weight,multifunctional BaNb_(2)O_(6):Yb^(3+)/Er^(3+)/Tm^(3+)transparent glass-ceramics were success-fully ... In order to meet the needs of new materials gradually developing towards miniaturization,integration,and light weight,multifunctional BaNb_(2)O_(6):Yb^(3+)/Er^(3+)/Tm^(3+)transparent glass-ceramics were success-fully prepared by melt quenching and controllable crystallization.Its structure,luminescence,and en-ergy transmission were studied.Using the opposite temperature dependence of the Tm^(3+)emission band and the corresponding large energy level gap,a maximum relative sensitivity of 2.3%K^(-1)based on thermal coupling levels(TCLs)is obtained in a wide temperature range(298-673 K).The multi-ratio optical thermometry based on TCLs and non-TCLs is successfully realized by using the different emission bands of double emission centers,which makes it possible for self-reference optical temperature measurement modes.In addition,the transparent glass-ceramic exhibits excellent electrical properties under 700 kV cm^(-1)electric field:high discharge energy density(W_(d)=0.99 J cm^(-3)),huge instantaneous power density(225.3 MW cm^(-3)),and ultra-fast discharge rate(T_(0.9)≤15.8 ns).The prepared glass-ceramic is expected to be a new type of lead-free multifunctional photoelectric material for temperature sensors and transparent electronic devices. 展开更多
关键词 Glass ceramics Luminescence Optical thermometry Energy storage
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