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Dendrobium offi cinale flowers flavonoids enriched extract protects against acute ethanol-induced gastric ulcers via AMPK/PI3K signaling pathways
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作者 Zhiyu Zhang Hualing Xie +3 位作者 Mohamed A.Farag Zhenhao Li Qingping Wu Ping Shao 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第6期3661-3679,共19页
Gastric ulcer is a widespread disease caused by various etiologies.Dendrobium offi cinale flowers exert several health benefits owing to their rich flavonoid content.In this study,protective effects and possible actio... Gastric ulcer is a widespread disease caused by various etiologies.Dendrobium offi cinale flowers exert several health benefits owing to their rich flavonoid content.In this study,protective effects and possible action mechanisms of D.offi cinale flowers’flavonoid enriched extract(DOFF)were assessed against gastric ulcer.The result of sodium nitrite-aluminum nitrate colorimetry showed that 52.34%of the total extractive was flavonoid,and ultra-high performance liquid chromatography time of flight mass spectrometer(UPLC-QTOF/MS)revealed the presence of 28 components in DOFF of which 14 belonged to flavonoids.In addition,in vivo assay revealed DOFF potential in reducing the formation of ethanol-induced gastric mucosal lesions,with drop-in ulcer index from 64.33±8.76 to 32.00±4.47.Similar results were revealed in human gastric mucosal epithelia cells,with cells viability to increase from 27.2%to 61.6%post DOFF administration.To analyzed the protect effect of DOFF,we used Western blotting and immunofluorometric assay to revealed the expression levels of key proteins in cell pathways.The results showed that DOFF(320μg/mL)could increase the level of oxidation marker protein(HO-1),apoptosis regulatory protein(Bcl-2)and autophagy marker(LC3β)by 50.84%,43.85%,and 59.21%compared with ethanol-treated group respectively.Further analyzed of the mitochondrial activity and apoptosis pathway,we found that DOFF appeared to mitigate against ethanolinduced gastric mucosal injury via AMPK/mTOR/ULK1 and PI3K/AKT autophagy signaling pathways. 展开更多
关键词 dendrobium offi cinale flower ETHANOL FLAVONOIDs Gastric injury Autophagy
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Effects of Hormone Factors on the in vitro Culture Flowering Induction of Dendrobium officinate Kimura et Migo 被引量:8
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作者 岑秀芬 黄春红 韦鹏霄 《Agricultural Science & Technology》 CAS 2010年第4期75-79,共5页
[Objective]The aim was to select the suitable hormone factors for flowering induction in vitro culture of Dendrobium officinate Kimura et Migo.[Method]The test-tube plantlets from the stems of Dendrobium officinate Ki... [Objective]The aim was to select the suitable hormone factors for flowering induction in vitro culture of Dendrobium officinate Kimura et Migo.[Method]The test-tube plantlets from the stems of Dendrobium officinate Kimura et Migo were used as the experimental materials and MS medium as the basic medium.Comparative tests have been done between single-factor hormone treatments(different concentrations of PP333 or TDZ) and multi-factor hormone treatments(different combinations of PP333,TDZ,6-BA and NAA) to research the effects of hormone factors on the flowering induction of the plantlets.[Result]Among the single-factor hormone treatments,the suitable concentration and the rate of flower buds formation of PP333 treatment were 0.2 mg/L and 8.5%,the that of TDZ treatment were 0.06 mg/L and 15.5%;the effects of multi-factor hormone treatments on the flowering induction were ordered as follow:(PP333 + 6-BA + NAA + TDZ)〉 (PP333 + 6-BA + NAA)〉 (PP333 + 6-BA) and(PP333 + NAA) ;the most suitable treatment was PP333 0.3 mg/L + 6-BA 0.5 mg/L + NAA 0.5 mg/L + TDZ 0.06 mg/L,the rate of flower bud formation and the rate of the blossomed flower were respectly reached to 80.4% and 90.3%.[Conclusion]PP333 and TDZ showed the important effect on the flowering induction in vitro culture of Dendrobium officinate Kimura et Migo.The effect of TDZ was better than that of PP333.It is much more conducive to the flower bud formation,when using appropriate concentration of TDZ combined with other hormones properly. 展开更多
关键词 dendrobium officinate Kimura et Migo in vitro culture Hormone factor flowering induction
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Bougainvillea spectabilis flowers extract protects against the rotenone-induced toxicity 被引量:2
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作者 Omar M.E.Abdel-Salam Eman R.Youness +4 位作者 Nadia A.Ahmed Sayed A.El-Toumy Ahmed M.A.Souleman Nermeen Shaffie Dalia M.Abouelfadl 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第5期457-466,共10页
Objective:To investigate the effect of two extracts of Bougainvillea spectabilis(B. spectabilis) flowers with yellow and pink/purple on brain oxidative stress and neuronal damage caused in rats by systemic rotenone in... Objective:To investigate the effect of two extracts of Bougainvillea spectabilis(B. spectabilis) flowers with yellow and pink/purple on brain oxidative stress and neuronal damage caused in rats by systemic rotenone injection. Methods:Rotenone 1.5 mg/kg was given three times per week alone or in combination with B. spectabilis flowers extracts(25 mg or 50 mg) via the subcutaneous route for 2 weeks. Brain concentrations of the lipid peroxidation marker malondialdehyde(MDA),reduced glutathione,nitric oxide(nitrite),the pro-inflammatory cytokine interleukin-1beta(Il-1β) as well as butyrylcholinesterase,and paraoxonase-1(PON-1) activities,were determined. Histopathology and caspase-3 immunohistochemistry were also performed. Results:Rotenone resulted in significant increases of brain MDA(the product of lipid peroxidation),and nitric oxide content along with decreased brain reduced glutathione. There were also marked and significant inhibition of brain PON-1 and BCh E activities and increased Il-1β in brain of rotenone-treated rats. B. spectabilis flowers extract itself resulted in brain oxidative stress increasing both lipid peroxidation and nitrite content whilst inhibiting PON-1 activity. The yellow flowers extract inhibited BCh E activity and increased brain Il-1β. When given to rotenone-treated rats,B. spectabilis extracts,however,decreased lipid peroxidation while their low administered doses increased brain GSH. Brain nitrite decreased by the pink extract but showed further increase by the yellow extract. Either extract,however,caused further inhibition of PON-1 activity while the yellow extract resulted in further inhibition of BChE activity. Histopathological studies indicated that both extracts protected against brain,liver and kidney damage caused by the toxicant. Conclusions:These data indicate that B. spectabilis flowers extracts exert protective effect against the toxic effects of rotenone on brain,liver and kidney. B. spectabilis flowers extracts decreased brain lipid peroxidation and prevented neuronal death due to rotenone and might thus prove the value in treatment of Parkinson's disease. 展开更多
关键词 Bougainvillea spectabilis flowers EXTRACT ROTENONE Oxidative stress Parkinson’s disease
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Studies on Relationship Between Low Temperature Exotherms and Freezing Injury in Stem Tissues and Flower Buds of Mei Flower and David's Peach
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作者 Zhang Qixiang Liu WanxiaDepartment of Landscape Architecture. Beijing Forestry University 《北京林业大学学报》 CAS CSCD 北大核心 1992年第S2期93-101,共9页
Differential thermal analysis was utilized to determine midwinter hardiness of stem tissues and flower buds of mei flower (Prunus mume) and David’s peach (Prunus davidiana). Low temperature freezing exotherms were fo... Differential thermal analysis was utilized to determine midwinter hardiness of stem tissues and flower buds of mei flower (Prunus mume) and David’s peach (Prunus davidiana). Low temperature freezing exotherms were found to occur at -35℃ in Green Calyxs’ David’s peach and -18℃ in mei flower. A Low temperature exotherm was produced by the freezing of deep supercooling water which was detected in the wood tissues but not in the bark. Freezing processes of the wood and those of the bark appeared to be independent. Deep supercooling points of both species were found to be closely related to freezing injury and to their respective distributions. 展开更多
关键词 MEI flower David’s PEACH sUPERCOOLING LT exotherm
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Detection of " Candidatus Phytoplasma asteris" in Brussels Sprout and Its Possible Association with Flower Bud Failure in Poland
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作者 Maria Kamiflska Hanna Bemiak Piotr Kamifiski 《Journal of Life Sciences》 2012年第3期253-259,共7页
Severe growth abnormalities including shoot stunting, leaf blade reduction and flower bud failure of Brussels sprout were observed in Poland. The presence of phytoplasma in diseased as well as in healthy looking plant... Severe growth abnormalities including shoot stunting, leaf blade reduction and flower bud failure of Brussels sprout were observed in Poland. The presence of phytoplasma in diseased as well as in healthy looking plants, was demonstrated by nested polymerase chain reaction assay employing phytoplasma universal rRNA primer pairs-P1/P7 followed by R16F2n/R16R2. Products of PCR primed by R 16F2n/R 16R2 primer pair from naturally infected Brussels sprouts were sequenced. Comparison of the obtained 16S rDNAs revealed high nucleotide sequence identity between analyzed phytoplasma isolates (99.8%-100%). They were also nearly identical with the sequences of other phytoplasmas isolates from sub-group 16SrI-B, and they were classified as members of "Candidatus Phytoplasma asteris". 展开更多
关键词 Brussels sprout flower bud failure PHYTOPLAsMA 16s rDNA.
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Beijing’s Flower Markets
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《ChinAfrica》 2011年第5期62-62,共1页
Whether you want to keep your green thumb in shape, bring Mother Nature into your apartment, or buy flowers for a special occasion, you will find everything you want and even more in Beijing’s specialized markets. he... Whether you want to keep your green thumb in shape, bring Mother Nature into your apartment, or buy flowers for a special occasion, you will find everything you want and even more in Beijing’s specialized markets. here are some of the most popular and what they offer. 展开更多
关键词 BEIJING s flower Markets
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The Peony, China's King of Flowers
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作者 Huo Jianying 《China Today》 1995年第4期36-,41,共2页
ThePeony,China'sKingofFlowersBystaffreporterHUOJLANYINGFORSOMETHINGlike1,500yearsthepeonyhasbeenregardedasth... ThePeony,China'sKingofFlowersBystaffreporterHUOJLANYINGFORSOMETHINGlike1,500yearsthepeonyhasbeenregardedasthesymbolofwealth,l... 展开更多
关键词 China’s King of flowers
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GC-MS分析金钗石斛花挥发性成分 被引量:14
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作者 宋小蒙 王洪新 +2 位作者 马朝阳 寇兴然 贾启海 《食品与生物技术学报》 CAS CSCD 北大核心 2019年第9期133-138,共6页
分别采用顶空固相微萃取(SPME)和水蒸气蒸馏法(SD)提取金钗石斛花挥发性成分,用气相色谱-质谱联用技术(GC-MS)对其进行成分分析,采用峰面积归一化法计算各组分的相对质量分数。两种方法分别鉴定出63种和24种化合物,占总挥发性成分的80.... 分别采用顶空固相微萃取(SPME)和水蒸气蒸馏法(SD)提取金钗石斛花挥发性成分,用气相色谱-质谱联用技术(GC-MS)对其进行成分分析,采用峰面积归一化法计算各组分的相对质量分数。两种方法分别鉴定出63种和24种化合物,占总挥发性成分的80.49%和54.92%。其中,SPME法提出的挥发性成分质量分数较高的有柠檬烯(25.87%)、四氢柠檬醛(11.1%)、松油烯(8.7%)、2-呋喃甲醛(6.51%)、甲酸己酯(2.12%)等;SD法提出的挥发性成分质量分数较高的有亚油酸(36.92%)、庚烷(7.69%)、肉豆蔻酸(3.51%)、亚油酸甲酯(2.12%)等。 展开更多
关键词 金钗石斛花 挥发性成分 顶空固相微萃取 水蒸气蒸馏法 气相色谱-质谱联用
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4种香花型石斛花朵挥发性成分GC-MS分析 被引量:11
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作者 曹桦 许凤 +4 位作者 陆琳 姬语潞 陈翔 张宝琼 李涵 《中国农学通报》 2021年第13期56-62,共7页
旨在利用固相微萃取方法结合气相色谱-质谱联用仪(SPME/GC-MS),对香花型石斛花朵挥发性成分进行分析,为云南省香花型石斛兰种质资源筛选、新品种培育和石斛花精油产品的开发提供参考。通过SPME/GC-MS方法,对兜唇石斛、金钗石斛、铁皮石... 旨在利用固相微萃取方法结合气相色谱-质谱联用仪(SPME/GC-MS),对香花型石斛花朵挥发性成分进行分析,为云南省香花型石斛兰种质资源筛选、新品种培育和石斛花精油产品的开发提供参考。通过SPME/GC-MS方法,对兜唇石斛、金钗石斛、铁皮石斛和美花石斛4种香花型石斛盛花期花朵的挥发性成分进行测定和分析。从4种石斛花朵中共鉴定出挥发性成分80种,所共有的挥发性成分为反式α-罗勒烯和月桂烯。其中,兜唇石斛的主要挥发性成分为乙酸异辛酯和反式-α-罗勒烯,相对含量为45.86%和37.3%;金钗石斛的主要挥发性成分为β-石竹烯,相对含量最高为20.7%;铁皮石斛的主要挥发性成分为α-蒎烯、柠檬烯和桉叶油醇,其相对含量分别为31.49%、14.6%和13.6%;美花石斛的主要挥发性成分为乙酸异辛酯,相对含量为83.21%。石斛花朵中的挥发性成分及相对含量具有明显差异,主要挥发性成分对其香味起决定性作用。 展开更多
关键词 石斛属 香花型 挥发性成分 固相微萃取方法 气相色谱-质谱联用仪
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GC-MS法检测云南产细茎石斛花中挥发性成分 被引量:10
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作者 张聪 刘守金 +1 位作者 杨柳 胡江苗 《云南农业大学学报(自然科学版)》 CSCD 北大核心 2017年第1期174-178,共5页
利用气相色谱-质谱联用(GC-MS)方法研究细茎石斛花挥发性化学成分,为细茎石斛花茶质控标准以及与其他石斛花区分提供科学依据。采用正己烷回流法从云南产细茎石斛花中提取挥发性成分,并用气相色谱-质谱(GC-MS)联用技术对其化学成分进行... 利用气相色谱-质谱联用(GC-MS)方法研究细茎石斛花挥发性化学成分,为细茎石斛花茶质控标准以及与其他石斛花区分提供科学依据。采用正己烷回流法从云南产细茎石斛花中提取挥发性成分,并用气相色谱-质谱(GC-MS)联用技术对其化学成分进行分析鉴定。结果表明:分离出了91个色谱峰,鉴定出72个化合物。其中相对含量较高的有二十一烷(38.957%)、二十三烷(13.558%)、二十二烷(5.245%)、2-十七烷酮(2.072%)等。云南产细茎石斛花的挥发油中主要化学成分包括烷烃、烯烃、醇、酮、酸、酯、酚等,其中长链烷烃含量最多,该研究为对云南产细茎石斛的进一步开发应用提供理论依据。 展开更多
关键词 细茎石斛 石斛花茶 挥发性化学成分 GC-Ms
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ICP-OES测定铁皮石斛干花中多种元素 被引量:9
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作者 张珍林 韩邦兴 +3 位作者 刘莉彬 蹇敏 刘帅 陈存武 《中国野生植物资源》 CSCD 2020年第1期4-8,共5页
用微波消解和马弗炉灰化消解分别处理云南、浙江、霍山三种产地的铁皮石斛干花,再用电感耦合等离子体发射光谱仪(ICP-OES)定量分析多种元素含量,构建一种快速测定石斛干花元素含量的方法。结果表明,微波消解结合ICP-OES测出三产地石斛... 用微波消解和马弗炉灰化消解分别处理云南、浙江、霍山三种产地的铁皮石斛干花,再用电感耦合等离子体发射光谱仪(ICP-OES)定量分析多种元素含量,构建一种快速测定石斛干花元素含量的方法。结果表明,微波消解结合ICP-OES测出三产地石斛花存在常量元素K、Ca、Na、Mg和微量元素Se、Co、Cu、Mn、Fe、Cr、Sr、Zn、B,且含量均高于马弗炉消解结合ICP-OES测定结果;有害元素As、Pb、Cd、Hg和潜在有害元素Sb、Ba、Sn、Al、Ni均未检出;内标回收率均在92.5%-110.0%之间,相对标准偏差(RSD)<10%。试验探究出微波消解和ICP-OES的结合不仅效率高,检测成本低,运行稳定且测定结果准确可靠,可用于铁皮石斛干花中多元素分析研究。 展开更多
关键词 微波消解 马弗炉灰化消解 ICP-OEs 铁皮石斛干花 元素
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霍山石斛多糖通过激活GSK-3β信号通路减轻大鼠心肌缺血-再灌注损伤 被引量:9
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作者 房雪 韩吉春 +2 位作者 李德芳 王凤华 郑秋生 《中药材》 CAS 北大核心 2017年第4期925-930,共6页
目的:研究霍山石斛多糖抗心肌缺血-再灌注损伤的作用。方法:采用Langendorff离体灌流系统建造大鼠离体缺血-再灌注损伤模型。实验分为正常对照组(不停灌处理)、模型组(停灌20 min)及霍山石斛多糖低、中、高浓度(停灌前灌流已配制浓度为... 目的:研究霍山石斛多糖抗心肌缺血-再灌注损伤的作用。方法:采用Langendorff离体灌流系统建造大鼠离体缺血-再灌注损伤模型。实验分为正常对照组(不停灌处理)、模型组(停灌20 min)及霍山石斛多糖低、中、高浓度(停灌前灌流已配制浓度为0.1、0.5、1.0 mg/L的KH液10 min)组。利用生物多导记录仪连续测定血流动力学参数。通过TTC染色检测心肌梗死面积。并用ELISA法检测冠脉流出液中肌酸激酶(CK)和乳酸脱氢酶(LDH)的活性。ELISA法检测心肌组织中超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量、还原型谷胱甘肽/氧化型谷胱甘肽(GSH/GSSG)比率、白介素6(IL-6)和肿瘤坏死因子α(TNF-α)的含量。利用HE染色和TUNEL法分别检测心肌细胞的坏死和凋亡。Western blot检测心肌组织中GSK-3β的磷酸化水平。结果:与正常对照组比较,模型组出现严重的心肌坏死和极高的凋亡率,心功能下降,冠脉流出液中LDH和CK水平显著升高,心肌组织中MDA、IL-6和TNF-α含量显著升高,SOD的活性与GSH/GSSG比值均显著降低(P<0.01)。与模型组比较,霍山石斛多糖中、高剂量组的心肌坏死程度、梗死面积和细胞凋亡率显著降低,心功能显著改善;冠脉流出液中LDH、CK水平逐渐降低;心肌组织中MDA、TNF-α及IL-6含量显著降低,SOD活性和GSH/GSSG比值显著升高(P<0.01)。高剂量霍山石斛多糖可显著降低心肌细胞凋亡指数,提高心肌组织中GSK-3β磷酸化水平。结论:霍山石斛多糖具有显著的抗心肌缺血-再灌注损伤作用,其作用机制可能与激活GSK-3β信号通路发挥抗氧化、抗炎和抗凋亡有关。 展开更多
关键词 霍山石斛多糖 心脏保护 抗氧化 抗炎 抗凋亡 GsK-3Β
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应用ICP-MS测定油菜蜜、油菜花和油菜杆中微量元素(英文) 被引量:6
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作者 陈辉 王志斌 +3 位作者 常巧英 王伟 范春林 庞国芳 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2014年第2期548-552,共5页
应用电感耦合等离子体质谱(ICP-MS)测定了收集于9个采样点的油菜蜜及其蜜源油菜花和油菜杆中Na,Mg,P,K,Ca,Mn,Zn,Rb,Sr和Ba等10种元素。在油菜蜜、油菜花和油菜杆中K,P,Ca,Mg和Na等五种元素含量均明显高于Zn,Rb,Mn,Sr和Ba,前五种元素含... 应用电感耦合等离子体质谱(ICP-MS)测定了收集于9个采样点的油菜蜜及其蜜源油菜花和油菜杆中Na,Mg,P,K,Ca,Mn,Zn,Rb,Sr和Ba等10种元素。在油菜蜜、油菜花和油菜杆中K,P,Ca,Mg和Na等五种元素含量均明显高于Zn,Rb,Mn,Sr和Ba,前五种元素含量大小顺序为K>P>Ca>Mg>Na,后五种元素含量在三者中的大小顺序则不尽相同。油菜花和油菜杆中K,P和Ca三种元素的含量均高于1 000mg·kg-1,油菜花中P,Ca,Mn,Zn和Rb等五种元素的平均含量均高于油菜杆,可以初步推断油菜花富集元素的能力略强于油菜杆。在上述测定结果基础上,首次应用雷达图对油菜蜜及其蜜源油菜花和油菜杆中10种元素的关系进行了研究,主要是为了对将油菜花中元素含量用于蜂蜜溯源研究的可能性进行探索。从雷达图可以看出,10种元素在油菜蜜、油菜花和油菜杆中的星形基本类似。此研究为油菜蜜的相关研究提供基础数据,同时为利用油菜花中元素含量代替油菜蜜中元素含量进行油菜蜜溯源提供了一定的科学依据。 展开更多
关键词 油菜蜜 油菜花 油菜杆 微量元素 雷达图谱
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天然脱落酸(S-ABA)在月季切花保鲜上的应用 被引量:13
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作者 叶姝 李凌 《现代农业科学》 2008年第1期31-33,36,共4页
天然脱落酸(S-ABA)是一种高效的植物生长调节剂,它具有促进植物在水分胁迫下自动关闭气孔的功效,从而达到减少水分蒸发的作用。将不同浓度的S-ABA应用到月季切花保鲜上,并且对其生理变化进行追踪测定,结果表明:低浓度的S-ABA对月季切花... 天然脱落酸(S-ABA)是一种高效的植物生长调节剂,它具有促进植物在水分胁迫下自动关闭气孔的功效,从而达到减少水分蒸发的作用。将不同浓度的S-ABA应用到月季切花保鲜上,并且对其生理变化进行追踪测定,结果表明:低浓度的S-ABA对月季切花具有延长花期、保持切花品质的效果,而高浓度的S-ABA对月季切花具有促进切花短时间内开花的效果。实验过程中,月季切花保鲜的最佳浓度为:1.0mg/L和2.0mg/L。 展开更多
关键词 月季 切花 保鲜 天然脱落酸 气孔关闭
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花状Zn_(0.76)Co_(0.24)S纳米材料的制备及电化学性能研究 被引量:3
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作者 方林霞 兰梦迪 +1 位作者 刘冰 曹悦 《信阳师范学院学报(自然科学版)》 CAS 北大核心 2022年第4期615-620,共6页
采用简单的水热合成法制备了双过渡金属硫化物Zn_(0.76)Co_(0.24)S纳米材料,并作为超级电容器电极材料。该材料具有花状多孔的微观形貌,花瓣为超薄纳米片结构。这样独特的结构能为电化学反应提供丰富的活性位点,为离子的传输提供便利的... 采用简单的水热合成法制备了双过渡金属硫化物Zn_(0.76)Co_(0.24)S纳米材料,并作为超级电容器电极材料。该材料具有花状多孔的微观形貌,花瓣为超薄纳米片结构。这样独特的结构能为电化学反应提供丰富的活性位点,为离子的传输提供便利的通道,同时也为反复充放电过程中材料体积的变化提供了缓冲空间。三电极体系测试结果表明:Zn_(0.76)Co_(0.24)S电极在电流密度为1 mA/cm^(2),比电容高达2031.0 C/g;当电流密度增大到30 mA/cm^(2)时,电容量仍可保持在888.9 C/g;在电流密度为10 mA/cm^(2)下循环充放电5000圈,电容量保持率为90.25%,表现出较高的电容量、优异电容稳定性以及循环性能。采用Zn_(0.76)Co_(0.24)S电极与活性炭(AC)构建的混合超级电容器Zn_(0.76)Co_(0.24)S∥AC也展现了令人满意的性能。 展开更多
关键词 Zn_(0.76)Co_(0.24)s 双过渡金属硫化物 花状纳米结构 超级电容器 电化学性能
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Valentine’s Day
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作者 王宗文 《语言教育》 2002年第2期15-17,共3页
Every February,across the country,candy,flowers,and gifts are exchanged between loved ones,all in the name of St.Valentine.But who is thismysterious saint and why do we celebrate thisholiday?
关键词 flowers exchanged celebrate GREETING BEGIN Valentine s DAY FERTILITY himself TODAY
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硫化氢信号对大白菜FLCs时空表达模式的调控作用
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作者 张丽萍 张林林 +6 位作者 曹海艳 郝雪峰 刘纹琪 刘志强 刘旦梅 金竹萍 裴雁曦 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2023年第7期972-979,共8页
硫化氢(H_(2)S)是一种气体信号分子,可以促进植物的开花,且这一过程与开花的关键因子FLOWERING LOCUS C(FLC)有关。大白菜中已报道的FLC同源基因有4种。本研究对这4种FLC同源基因进行了时空表达模式和功能分化研究,以及H_(2)S对BrFLCs... 硫化氢(H_(2)S)是一种气体信号分子,可以促进植物的开花,且这一过程与开花的关键因子FLOWERING LOCUS C(FLC)有关。大白菜中已报道的FLC同源基因有4种。本研究对这4种FLC同源基因进行了时空表达模式和功能分化研究,以及H_(2)S对BrFLCs的表达模式的调控作用进行了探讨。结果表明:4种BrFLCs同源基因的表达表现出不同的时空特异性。其中,BrFLC 1、2和3的发育时期表达模式与拟南芥AtFLC相似,而BrFLC 5未表现出发育时期特异性。BrFLC 1只在叶中表达,而BrFLC 2在不同组织中均有表达,BrFLC 3在各组织中的表达量最高,但组织特异性差异不明显,BrFLC 5表达量不高且不具有组织特异性。经外源H_(2)S处理,BrFLCs表达略有下调,叶片中的BrFLC 2表达量最低。H_(2)S还能够不同程度地调节BrFLCs下游基因的表达,这可能和BrFLCs的表达模式改变有关。综上所述,H_(2)S可能通过调节大白菜中4个BrFLCs基因的表达模式影响其植株的开花时间。 展开更多
关键词 大白菜 FLC同源基因 硫化氢 时空表达模式 下游基因
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值得的十五年——从SLG到SCR/SP11 被引量:5
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作者 崔海洋 赖钊 薛勇彪 《Acta Botanica Sinica》 CSCD 2001年第1期1-5,共5页
Self_incompatibility (SI) is a major genetic mechanism to prevent self_fertilization in flowering plants and, in most cases, controlled by a single multiallelic locus, known as the S locus. In Brassica , the genes med... Self_incompatibility (SI) is a major genetic mechanism to prevent self_fertilization in flowering plants and, in most cases, controlled by a single multiallelic locus, known as the S locus. In Brassica , the genes mediating both stylar ( SRK, S receptor kinase) and pollen (SCR/SP11, S locus cystein rich protein/ S locus protein 11) expression of self_incompatible reaction have been characterized though the first S locus_encoded gene, SLG (S locus glycoprotein), was isolated nearly fifteen years ago. These findings have finally unveiled the molecular partners in pollen recognition during self_incompatible reaction in Brassica . 展开更多
关键词 显花植物 自交不亲和性 s位点基因 芸苔基因 花粉识别 受精
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龙首山南麓新发现的地震地表破裂带——兼论1954年山丹M_(S)71/4地震发震构造 被引量:2
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作者 赵迪 陈鹏 +4 位作者 李荣西 吴小力 赵帮胜 刘齐 王晓雪 《地质力学学报》 CSCD 北大核心 2022年第4期501-512,共12页
基于详细的遥感解译和野外调查,发现龙首山南缘断裂发育有较新的地震地表破裂遗迹,包括断层坎、地震鼓包、河道的系统位错等断层地貌标志,破裂带总长度超过20 km,沿断裂走向其垂向位移介于0.35~4 m,水平位移介于0.3~1.9 m,龙首山南缘断... 基于详细的遥感解译和野外调查,发现龙首山南缘断裂发育有较新的地震地表破裂遗迹,包括断层坎、地震鼓包、河道的系统位错等断层地貌标志,破裂带总长度超过20 km,沿断裂走向其垂向位移介于0.35~4 m,水平位移介于0.3~1.9 m,龙首山南缘断裂主体表现为逆冲性质,仅在西端表现为局部左旋走滑的性质。通过剖面和探槽揭示,龙首山南麓地区全新世以来发生多次断层活动,最新的一次在约3.96 ka以来。经过与区域内的强震记录比对,认为此次新发现的地震地表破裂带可能是1954年山丹M_(S)71/4地震所致。1954年山丹M_(S)71/4地震在浅表沿两条断裂同时发生了地表破裂,表现为正花状构造的变形样式。这种同震位移分配现象以往多发现于走滑型地震中,此次在逆冲型地震中发现。龙首山南缘断裂地表破裂带的发现为揭示1954年山丹地震的震源过程和破裂样式提供了新的证据和思路。 展开更多
关键词 青藏高原东北缘 1954山丹M_(s)71/4地震 龙首山断裂带 同震地表破裂 花状构造
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Structural engineering of 3D hierarchical Cd0.8Zn0.2S for selective photocatalytic CO2 reduction 被引量:13
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作者 Lei Cheng Dainan Zhang +2 位作者 Yulong Liao Jiajie Fan Quanjun Xiang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期131-140,共10页
The solar-driven catalytic conversion of CO2 to useful chemical fuels is regarded as an environmentally friendly approach to reduce the consumption of fossil fuels and mitigate the greenhouse effect.However,it is high... The solar-driven catalytic conversion of CO2 to useful chemical fuels is regarded as an environmentally friendly approach to reduce the consumption of fossil fuels and mitigate the greenhouse effect.However,it is highly intriguing and challenging to promote the selectivity and efficiency of visible-light-responsive photocatalysts that favor the adsorption of CO2 in photoreduction processes.In this work,three-dimensional hierarchical Cd0.8Zn0.2S flowers(C8Z2S-F)with ultrathin petals were successfully synthesized through an in-situ self-assembly growth process using sodium citrate as a morphology director.The flower-like Cd0.8Zn0.2S solid solution exhibited remarkable photocatalytic performance in the reduction of CO2,generating CO up to 41.4μmol g^−1 under visible-light illumination for 3 h;this was nearly three times greater than that of Cd0.8Zn0.2S nanoparticles(C8Z2S-NP)(14.7μmol g^−1).Particularly,a comparably high selectivity of 89.9%for the conversion of CO2 to CO,with a turnover number of 39.6,was obtained from the solar-driven C8Z2S-F system in the absence of any co-catalyst or sacrificial agent.Terahertz time-domain spectroscopy indicated that the introduction of flower structures enhanced the light-harvesting capacity of C8Z2S-F.The in situ diffuse reflectance infrared Fourier transform spectroscopy unveiled the existence of surface-adsorbed species and the conversion of photoreduction intermediates during the photocatalytic process.Empirical characterizations and predictions of the photocatalytic mechanism demonstrated that the flower-like Cd0.8Zn0.2S solid solution possessed desirable CO2 adsorption properties and an enhanced charge-transfer capability,thus providing a highly effective photocatalytic reduction of CO2. 展开更多
关键词 Cd0.8Zn0.2s flowers self-assembly growth Photocatalytic CO2 reduction High selectivity Visible-light irradiation
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