174 research outputs found

    钌亚丙二烯基配合物与肼的反应性质:丙烯腈配合物的生成(英文)

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    以双齿P,N-配体8-(二苯基膦基)喹啉(DPPQ)为支撑配体的钌亚丙二烯基配合物[RuCl(=C=C=CR2)(DPPQ)2]-[BPh4](3a:R=苯基;3b:CR2=FN=亚芴基)可由双核钌配合物[Ru(μ-Cl)(DPPQ)2]2[BPh4]2(1)分别与过量的1,1-二苯基炔丙醇(2a)或9-乙炔-9-芴醇(2b)反应得到.配合物3易与肼在室温下反应生成丙烯腈的钌配合物[RuCl(N≡C—CH=CR)2)(DPPQ))2][BPh)4](4a:R=苯基;4b:CR)2=FN=亚芴基),该反应涉及肼对亚丙二烯基配体α-碳原子的分子间亲核进攻,是首例肼对金属亚丙二烯基加成生成丙烯腈的反应.配合物4与过量的丙炔醇2反应可释放出3,3-二苯基丙烯腈(5a)或3-芴基丙烯腈(5b),并再生亚丙二烯基配合物3.此外,初步考察了配合物1对端基炔丙醇与肼反应生成丙烯腈的催化活性,结果表明该催化反应的确可以进行,但是得到的丙烯腈产物的产率不高.尽管结果不是很理想,但是这些研究表明可望发展端基炔丙醇与肼经由过渡金属亚丙二烯基中间体转化为丙烯腈的新催化反应.Project supported by the National Basic Research Program of China(973 Program,No.2012CB821600);;the Program for Changjiang Scholars and Innovative Research Team in University(No.IRT_17R65)~

    Dynamic Response of a Life-saving Ball System to the Shock Wave of Gas Explosion

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    介绍矿难救生球系统(简称球)的原理及结构,构建巷道空间和球的分析模型,运用数值分析的方法,分别选择3种球体材料和3种球体厚度进行计算,对该系统在瓦斯爆炸冲击波作用下的动态响应进行研讨,分析冲击波作用下球表面的变形、等效应力、等效塑性应变以及球体材料、厚度等因素对球动态响应的影响。结果表明:运用数值分析的方法,可以为救生球系统设计建立一个仿真的实验环境,为优化系统设计、提高设计效率提供参考数据。The principle and structure of a life-saving ball system(referred to as 'ball' for short hereinafter)were introduced. Analytical model of the laneway space and the ball were established. By selecting three kinds of balls with different materials and thickness for calculation, the dynamic response of the ball to the shock wave of gas explosion was respectively analyzed with numerical analysis methods. The analysis focused on the deformation, the equivalent stress and the equivalent plastic strain of the surface of the ball under shock wave, and the effect of the material and thickness on the dynamic response of the ball. The analysis results show that a simulation experimental environment can be established and reference data can be provided for the design of a life-saving ball system by using numerical analysis methods.福建省重点项目(2006Z0027

    瓦斯爆炸冲击波传播过程的数值模拟

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    建立瓦斯爆炸沿巷道传播的分析模型,运用DYTRAN软件进行分析,得到瓦斯爆炸冲击波沿巷道的传播过程的参数变化及障碍物表面的等效应力分布。结果表明,应用DYTRAN可以很好地模拟瓦斯爆炸传播过程及冲击波对障碍物的短暂的瞬态动力学过程,对进行矿难救生系统的设计研究有重要意义

    Significance of Mangrove Pollen in Research of Marine Geology

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    红树林是热带—亚热带海岸潮间带的一种特有的植被类型和指示植物 .根据沉积物中出现的红树植物花粉种类和数量 ,推测了海滨红树林的演化、海面升降、海岸线变迁 ,追溯了古海流和沉积物来源 ,阐述了红树植物花粉在海洋地质研究中对深入探讨古环境变化和海陆相互作用等方面的重要意义 .Mangrove flora are special vegetation and indicative plants existing in certain areas of tropical and subtropical coasts.According to the variety and quantity of mangrove pollen discoveried in the sediments,this paper inferred the evolution of mangrove flora and changes of sea level and paleo-shoreline.Mangrove pollen also provide evidence for tracing paleo-ocean current and sediments source.In marine geological research,the study on mangrove pollen is also important for exploring paleoenvironment changes and ocean-continent interaction.国家自然科学基金资助项目 ( 4 95 76 2 87) ;; 华东师范大学河口海岸国家重点实验室资助项目 ( 2 0 0 0 0 1) ;; 国家海洋局海底科学 重点实验室资助项目 ( 2 0 0 1-4

    Succession of phytoplankton community in exalted shrimp ponds during culture process

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    通过对湛江东海岛北寮村和庵里村各2个高位虾池养殖过程的浮游植物演替和主要理化因子进行调查,研究浮游植物群落的演替过程对高位虾池的健康养殖的影响。结果表明:4池共检出浮游植物7门76属140种;对虾生长正常的北寮高位虾池演替优势种主要有螺旋环沟藻、椭圆扁胞藻、海链藻、湖泊束球藻密胞变种、裸甲藻、卵囊藻、微囊藻、锥形斯克里普藻、色球藻和尖尾蓝隐藻等,而对虾发病的庵里高位虾池演替优势种主要有铜绿微囊藻、柔弱布纹藻、咖啡形双眉藻、小席藻、卷曲鱼腥藻、水生集胞藻、衣藻、尖尾蓝隐藻和螺旋环沟藻等,北寮正常虾池浮游植物种类(包括优势种)较对虾发病的庵里虾池多而复杂;对虾生长正常池优势种的演替快而门类交替,而对虾发病池呈现硅藻到蓝藻优势的演替;对虾生长正常池浮游植物密度随养殖过程延伸呈上升态势,而对虾发病池浮游植物密度初期增加病害后下降;养殖过程浮游植物密度与主要理化因子的相关关系不显著;对虾生长正常的北寮高位池多样性指数与均匀度高于对虾发病的庵里高位池,而优势度却较低。水体理化因子变化平缓,浮游植物有较高的多样性指数和均匀度、较低的优势度对于稳定虾池养殖水环境有重要作用。An investigation was made on the succession of phytoplankton community and the main physical and chemical factors of water body in exalted shrimp ponds in Beiliao and Anli villages of Donghai Island,Zhanjiang during culture process,with the influence of the succession on the culture process analyzed.A total of 140 species of phytoplankton belonging to 76 genera and 7 phyla were identified.The dominant species in the two ponds with normal shrimp growth in Beiliao village were Gyrodinium spirale,Platymonas elliptica,Thalassiosira sp.2,Gomphosphaeria lacustris var.compacta,Gymnodinium sp.1,Oocystis sp.,Microcystis sp.,Scrippsiella trochoidea,Chroococcus sp.,and Chroomonas acuta,while those in the two ponds with shrimp disease occurrence in the process of culture in Anli village were Microcystis aeruginosa,Gyrosigma tenuissimum,Amphora coffeaeformis,Phormidium tenue,Anabaena circinlis,Synechocydtis aquetilis,Chlamydomonas sp.2,Chroomonas acuta,and Gyrodinium spirale.The phytoplankton species,including dominant ones,were more abundant and complex in normal ponds than in disease-affected ponds.In normal ponds,the dominant species succeeded rapidly and alternated in phyla,while in disease-affected ponds,only Bacillariophyta species were replaced by Cyanophyta species during the succession.The phytoplankton cell density increased during the culture process in normal ponds,but decreased after a temporary increase at early culture stage in disease-affected ponds.No significant relationships were observed between the phytoplankton cell density and the main physical and chemical factors in the ponds during culture process.The diversity and evenness of phytoplankton species were higher in the normal ponds in Beiliao than in the disease-affected ponds in Anli,while the dominance degree of species was in reverse.The mild variability of water body's physical and chemical factors as well as the high diversity and evenness but low dominance degree of phytoplankton species played important roles in keeping aquatic environment steady and healthy during the culture process in exalted shrimp pond.广东省自主创新重大科技资助项目(2007A032600004

    甲酸甲酯氢解制甲醇铜基催化剂上吸附物种的现场红外光谱表征

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    应用原位红外光谱的方法,在反应现场条件下,研究了促进型甲酸甲酯(MF)氢解制甲醇铜铬催化剂上的化学吸附物种.结果表明,在MF氢解反应条件下,工作态催化剂上主要的化学吸附物种和反应中间物种是CH3O-CHO…H-O(a)(1751,2730,1455cm-1)、CH3O-CHO…Cu+(a)(1654,2730,1455cm-1)、CH3O-CHO…Cr3+(a)(1552,2730,1445cm-1)和OCH3(3012,2946,1455cm-1).结合对该催化剂活性位本质的探讨,推断了甲酸甲酯氢解制甲醇的主要反应途径

    过渡金属团簇Cr_n结构的理论研究

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    应用量子化学从头算方法研究了纯过渡金属Cr团簇中的各种组态及金属键,在HF/Lanl2DZ水平进行了研究,并用MP2做了电子相关能校正.通过对其几何结构和电子结构的研究预测:Cr3团簇有直线、V形、正三角形构型;Cr4有平面构型也有立体构型,平面构型原子间存在强弱键现象,即原子间存在定域键;Cr5、Cr6则有平面构型也有立体构型,平面构型有定域键也有离域键,立体构型则都是离域键

    Pregnane X receptor involves in the effect of aflatoxin B1 on necroptosis in human normal L02 liver cells

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    目的初步探讨孕烷X受体(PXr)对黄曲霉毒素b1(Afb1)诱导肝细胞dnA损伤和坏死性凋亡的影响。方法采用已构建的PXr高表达l02-PXr和空白载体对照l02-P b细胞;实时荧光定量PCr(Q rT-PCr)检测细胞nr1I2和CyP3A4 M rnA水平改变;蛋白免疫印迹(WESTErn blOTTIng)检测细胞内PXr和坏死性凋亡下游效应自噬分子lC3-Ⅰ和lC3-Ⅱ蛋白相对表达含量;双核微核试验(CbMn)检测细胞遗传损伤情况;采用噻唑蓝(MTT)法测定Afb1对细胞活性抑制影响;利用坏死性凋亡抑制剂nEC-1构建坏死性凋亡抑制的细胞模型,验证Afb1诱导的坏死性凋亡的效应。结果与l02-P b细胞相比,l02-PXr细胞nr1I2 M rnA和PXr蛋白显著上调(均P<0.001)。Afb1显著地诱导l02-P b和l02-PXr细胞中CyP3A4 M rnA上调(均P<0.05),在l02-PXr细胞中的效应更为明显。与对照组相比,Afb1在5~30μMOl/l呈剂量反应关系诱导l02-P b和l02-PXr细胞的微核率增高(均P<0.05),l02-PXr细胞更为明显;同时,Afb1明显地诱导两株细胞的核芽率和核桥率,但随Afb1剂量增高都有下降趋势。细胞活性随Afb1浓度(1.875~120μMOl/l)增加呈剂量反应关系抑制(均P<0.05);且相对于l02-P b细胞,l02-PXr细胞对Afb1处理48 H诱导的细胞活性抑制作用更为敏感(P<0.05)。nEC-1可显著性抑制Afb1诱导的l02-PXr细胞活性抑制率(P<0.05),然而却不能降低Afb1诱导l02-P b细胞活性抑制率。此外,Afb1显著性诱导l02-P b和l02-PXr坏死性凋亡下游lC3-Ⅱ的上调(均P<0.05);且与l02-P b细胞相比,nEC-1对Afb1诱导的l02-PXr细胞活性抑制和lC3-Ⅱ上调的抑制效果更为明显(P<0.05)。结论 PXr参与Afb1诱导人肝细胞dnA损伤介导的坏死性凋亡,与PXr促进Afb1诱导CyP3A4基因上调有关。Objective To investigate the effects of pregnane X receptor(PXR) over expression on aflatoxin B1(AFB1)-induced DNA damage and necroptosis in human normal liver L02 cells.Methods The established cells models of stable transfection of over expression PXR(L02-PXR) and null vector p Babe-puro(L02-p B) were used.The background levels of NR1I2 m RNA and PXR protein, and the expression of AFB1-induced CYP3A4 m RNA and LC3-I / LC-3II protein were determined by the real time PCR(q RT-PCR) and Western blotting, respectively.The cytokinesis-block micronucleus(CBMN)assay was adopted to evaluate the genotoxicity.The cell viability inhibition rate was determined by MTT assay, after treatment with different doses of AFB1.The inhibition models of necroptosis were established by treatment with necroptosis inhibitor Nec-1.Results The expression of NR1I2 m RNA and PXR protein in L02-PXR cells were higher than that in L02-p B cells(all P<0.001).The level of CYP3A4 m RNA was significantly up regulated in L02-p B and L02-PXR cells by treatment with AFB1(all P<0.05).Compared with control group(Ctrl), MN frequencies in L02-p B and L02-PXR cells were significantly increased by treatment with AFB1 in a dose-dependent manner(all P <0.05), especially, in L02-PXR cells.Meanwhile, NBD and NBP frequencies were significantly increased by treatment with AFB1.However, AFB1 with a higher dose induced downward trends in frequencies of NBD and NBP.Moreover, the inhibition rate of cell viability was increased after treatment with AFB1(1.875~120 μmol / L) in a dose-dependent manner(all P <0.05); specifically, the inhibitory effects of AFB1-treatment after 48 h were significantly stronger in L02-PXR cells than in L02-p B cells(P <0.05).Interestingly, necroptosis inhibitor Nec-1 could inhibit AFB1-induced cell death in L02-PXR cells(P<0.05).On the contrary, Nec-1 could not prevent L02-p B cells from death by treatment with AFB1.In addition, the expression of necroptotic LC3-II, a classical marker of autophagy, was significantly increased by treatment with AFB1 in two cell lines(all P <0.05).Notably, pre-treatment with Nec-1 was able to block the inducement of necroptotic LC3-II in a more efficiently way in L02-PXR cells than in L02-p B cells(P <0.05).Conclusion PXR involved in the effect of AFB1 on necroptosis by DNA damage mediation in human liver cells;specifically, the up regulation of CYP3A4 gene may relate to the AFB1-induced DNA damage.国家自然科学基金(81172705;81072334); 广东省自然科学基金(S2011020002769); 福建省自然科学基金(2014J01372

    Effects of cadmium on promoter methylation and transcriptional level of PPP2R1A gene in hepatocytes

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    目的分析镉染毒处理肝细胞中蛋白磷酸酶2A(PP2A)-Aα支架亚基基因PPP2r1A启动子区甲基化状态及其转录水平的改变。方法采用永生化人正常肝l02细胞及肝细胞癌HEP g2细胞为研究对象,对其进行以下分组和处理:1低、中和高剂量氯化镉(Cd Cl2)处理组,分别予浓度为20.0、40.0和60.0μMOl/l Cd Cl2处理24 H;2低、中和高剂量5-氮杂-2’-脱氧胞苷(5-AzA-d C)处理组,分别予浓度为2.5、5.0和10.0μMOl/l 5-AzA-d C处理48 H;3 5-AzA-d C组予浓度为5.0μMOl/l的5-AzA-d C处理48 H,Cd Cl2组予浓度为40.0μMOl/l的Cd Cl2处理24 H,(5-AzA-d C+Cd Cl2)组予浓度为5.0μMOl/l的5-AzA-d C预处理48 H后再予浓度为40.0μMOl/l Cd Cl2处理24 H;4 Cd Cl2处理组予浓度为40.0μMOl/l Cd Cl2处理24 H。上述4种分组均设对照组,予等体积生理氯化钠溶液或二甲基亚砜处理。经1~3处理后的细胞采用实时荧光定量聚合酶链反应(PCr)检测PPP2r1A、金属硫蛋白1b(MT1b)和dnA甲基转移酶3A(dnMT3A)的MrnA转录水平(以对照组水平为1.00)。经4处理后的细胞采用亚硫酸氢盐修饰后PCr扩增PPP2r1A启动子区克隆测序检测CP g岛的甲基化情况。结果 l02细胞和HEP g2细胞中,不同剂量Cd Cl2处理组PPP2r1A MrnA转录水平随镉处理剂量增高呈剂量依赖性下降(P0.05)。结论外源化学物Cd Cl2可诱导肝细胞中PPP2r1A转录水平降低,可能与镉能够引起目的基因启动子区甲基化状态改变有关,提示PP2A亚基基因的表观遗传学调控可影响镉诱导的肝细胞功能。Objective To analyze the effects of cadmium on the promoter methylation and transcriptional level of protein phosphatase 2A( PP2A)-Aα supported subunit gene PPP2R1 A gene in hepatocytes.Methods The immortalized human fetal liver cell line L02 and the hepatocellular carcinoma cell line Hep G2 were selected as the research objects: 1 Cells were treated with low-,medium- and high-dose( 20.0,40.0 and 60.0 μmol / L) cadmium chlorid( Cd Cl2) for 24 h.2Cells were treated with low-,medium- and high-dose( 2.5,5.0 and 10.0 μmol / L) 5-aza-2'-deoxycytidine( 5-Aza-d C)for 48 h.3 Cells were given 5.0 μmol / L for 48 h in 5-Aza-d C group,cells were exposed to 40.0 μmol / L Cd Cl2 for 24 h in Cd Cl2 group and cells were exposed to 40.0 μmol / L Cd Cl2 for 24 h after 48 h pretreatment of 5.0 μmol / L 5-Aza-d C in( 5-Aza-d C + Cd Cl2) group.4 Cells were treated with 40.0 μmol/L Cd Cl2 for 24 h in Cd Cl2 group.The above groups were all given the controls with the same volumes of physiological sodium chloride solution or dimethyl sulfoxide.Real-time fluorescent quantitative polymerase chain reaction( PCR) detection was used to detect the mRNA transcriptional levels of PPP2R1 A,Metallothionein 1B( MT1B),DNA methyltransferase 3A( DNMT3A) after treatments 1-3.After treatment4,cloning sequencing was used to detect the Cp G island methylation status of PPP2R1 A promoter after bisulfite sequencing PCR.Results In L02 and Hep G2 cells,the transcriptional levels of PPP2R1 A mRNA in Cd Cl2 group were decreased in a dose-dependent manner( P 0.05).Conclusion It was indicated the Cd Cl2 could lead to the transcription inhibition of PPP2R1 A,and the effect may be related with the change of its promoter methylation status.These data showed epigenetic regulation of PP2 A subunit genes may affect the function of hepatocytes exposed to cadmium.国家自然科学基金(81172705;81072334;81130052); 广东省自然科学基金重点项目(S2011020002769

    一种浮动复合型人工鱼巢

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    一种浮动复合型人工鱼巢,包括浮动框架,在浮动框架的四周设有多个固定装置,并且浮动框架与固定装置之间是采用活动连接,在浮动框架上分布设有多根缆绳,在缆绳的端部固接有沉子,在沉子与浮动框架之间的缆绳上固定连接多个粘附基质,本实用新型提供一种能为产粘性卵鱼类提供产卵场所的浮动复合型人工鱼巢,能有效促进鱼类资源的保护和可持续利用。</p
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