12 research outputs found

    Effects of Jiangu Granules on the proliferation of osteoblasts through G_1/S phase cell-cycle regulated proteins

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    目的观察健骨颗粒对成骨细胞G_1/S期调控的影响,探讨健骨颗粒促进成骨细胞增殖的作用机制。方法制备健骨颗粒血清组、模型血清组和雌二醇血清组。采用酶消化法培养SD大鼠成骨细胞,健骨颗粒含药血清干预,以模型血清和雌二醇血清为对照。运用流式细胞术检测成骨细胞增殖周期,荧光定量PCR法检测成骨细胞G_1/S期调控蛋白Cyclin E、CDK2、p21和转录因子E2F-1 m RNA的表达。结果 15%的雌二醇血清与健骨颗粒血清干预48 h,成骨细胞增殖速度均明显快于模型血清组(P<0.01);G_0/G_1期成骨细胞比例明显降低(P<0.01),S期、G_2/M期细胞比例及增殖指数则明显高于模型血清组(P<0.01);与模型血清组比较,雌二醇血清组与健骨颗粒血清组能提高成骨细胞Cyclin E、CDK2及转录因子E2F-1 m RNA的表达(P<0.01),而降低p21的表达(P<0.01)。结论健骨颗粒通过调节成骨细胞G_1/S期调控机制,推进成骨细胞顺利通过G_1/S检测点,促进成骨细胞增殖。Objective To observe the effects of Jiangu Granules on the G_1/S phase cell-cycle regulated proteins of osteoblasts, so as to reveal the mechanism of Jiangu Granules in promoting osteoblasts proliferation. Methods The Jiangu Granules-serum group, model-serum group and estradiol-serum group were prepared. Osteoblasts of SD rats were cultivated by enzymatic digestion and intervened with Jiangu Granules-serum, model-serum and estradiol-serum(as control) respectively. The cell cycles were analyzed by flow cytometry, while the fluorescence quantitative PCR was applied to measure cyclin E, CDK2, p21 and E2F-1 m RNA. Results The cell proliferation rates of osteoblasts intervened with estradiol serum and Jiangu Granules-serum for 48 hours were faster than that with the same concentration model-serum(P < 0.01). Compared with the model-serum group, the proportion of osteoblasts in the G_0/G_1 phase were significantly reduced after intervention with 15% of estradiol serum and Jiangu Granules-serum for 48 hours(P < 0.01),while the proportion of cells in S phase, G_2/M phase and proliferation index was much higher(P < 0.01). The expression of cycling E, CDK 2 and transcription factor E2F-1 m RNA of osteoblasts in the Jiangu Granules-serum group and the estradiol-serum group was higher than that of model-serum group(P < 0.01), while the expression of p21 m RNA was lower than the model-serum group(P < 0.01). Conclusion Jiangu Granules-serum can adjust the G_1/S phase cellcycle regulated mechanism in osteoblast, so as to push the cells passing G_1/S checkpoint and accelerate the proliferation of osteoblast.国家自然科学基金资助项目(81473706

    一种合成气直接制二甲醚的催化剂制备方法

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    一种合成气直接制二甲醚的催化剂制备方法,采用含有Cu,Zn和Al或Cu,Zn和Zr或Cu,Zn,Al和Zr的硝酸盐作为催化剂制备的原料,各组份的原子比为Cu/Zn/(Al+Zr)=1/0.4-0.7/0.03-0.3,脱水组分为固体酸,合成组分和脱水组分比例为1∶1-5∶1(重量比)。本发明制作过程简单,重复性好,所制备的催化剂粒度小,比表面高,各组份间接触紧密因而协同作用强,从而使催化剂对二甲醚合成具有较高的活性。带填

    NiMo/ZrO2加氢脱硫催化剂的研究

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    采用共浸法制备了未经焙烧直接硫化的NiMo/ZrO2(550)、NiMo/ZrO2(650)催化剂及550℃焙烧后再硫化的NiMo/ZrO2(550)-1催化剂,在连续流动微反装置上考察了NiMo/ZrO2系列催化剂对噻吩加氢脱硫反应的催化活性,并对催化剂进行了X射线光电子能谱(XPS)和Raman光谱表征.表征结果显示,以四方相ZrO2为载体的NiMo/ZrO2(650)催化剂,由于被硫化的更完全,催化活性高于以无定形相ZrO2为载体的NiMo/ZrO2(550)催化剂,说明载体的结构影响催化剂的催化活性;550℃焙烧后的NiMo/ZrO2(550)-1催化剂的催化活性低于未经焙烧直接硫化的NiMo/ZrO2(550)催化剂,这是由于高温焙烧增加了活性组分和载体之间的相互作用,降低了催化剂的硫化程度,进而降低了其催化活性,说明这种强相互作用不利于提高催化剂的催化活性

    合成气制备工艺和二甲醚合成工艺的集成

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    在固定床反应器中,用3种典型的天然气造气工艺制备的合成气制备二甲醚,考察了温度、压力、空速等反应条件对催化剂性能的影响.实验结果表明,由于合成气一步法合成二甲醚是一个体积减小的反应,随着压力的增加,CO转化率增加;随着空速的增加,CO转化率降低;随着温度的升高,CO转化率先增加,达到一定值后,逐渐开始下降.分别用丹麦Topscpe甲醇合成催化剂和国产甲醇合成催化剂制备了DME合成催化剂,对其性能进行比较发现,前者具有较好的低温催化性能.用CH4-Air-H2O-CO2转化工艺制备的合成气,即含氮合成气合成二甲醚在适当增加压力的条件下,可取得较高的CO单程转化率和二甲醚回收率,且天然气的消耗量较少

    Ni-V-O催化剂上丙烷氧化脱氢制丙烯的反应

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    考察了Ni-V-O系列催化剂对丙烷氧化脱氢反应的催化性能,结合XRD和电导法等表征结果研究了催化剂的物相结构与仙化活性之间的关系。结果表明:同n型半导体氧化物相比,p型半导体具有优良的催化性能,并且丙烯的选择性与催化剂中NiO及Ni3V2O8相的共存有关。适当控制反应条件,452℃时该系列催化剂可达到18.6%的丙烷转化率和49.9%的丙烯选择性

    丙烷氧化脱氢Ni-V-O催化剂的原位电导

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    应用原位电导方法测定了Ni-V-O系列催化剂的在氧+丙烷→氧→丙烷连续变化气氛下的电导率,确定其导电类型并与其丙烷氧化脱氢制丙烯催化性能的相关联,结果表明,p型半导体较n型半导体具有优良的催化氧化脱氢性能:在反应气氛下催化剂的p型半导性越大,n型半导性越小,其催化活性越高,这是由于p型半导体空穴导电,而n幸导体则为电子迁移导电,使得表面活性氧物种形成机理不同所致

    甲烷空气催化部分氧化制合成气与含氮合成气制二甲醚的研究

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    采用常规浸渍法制备了经镧和镁改性的镍基催化剂,以铜锌铝甲醇合成催化剂和HZSM-5分子筛通过机械混合制造了二甲醚合成催化剂,采用固定床流动反应色谱装置研究了甲烷空气催化部分氧化制合成气的催化性能,同时开展了以含氮合成气制备二甲醚的研究,结果说明,镍基催化剂对甲烷空气部分氧化制合成气在常压下具有高的转化率,随压力升高,随压力升高,转化率明显下降,并且催伦剂严重积炭,通过向反应体系添加H2O和CO2可以提高加压条件下的CH4转化率并抑制催化剂积炭,还可获得n(H2)/n(CO)接近2的合成气,满足合成二甲醚的要求,采用含氮合成气制备二甲醚,在压力7.0MPa,空速1000h^-1条件下,催化剂连续使用200h性能基本稳定,CO转化率在93%左右,DME选择性在77%左右,DME收率在72%左右

    JUNO Sensitivity on Proton Decay pνˉK+p\to \bar\nu K^+ Searches

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    The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in pνˉK+p\to \bar\nu K^+ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via pνˉK+p\to \bar\nu K^+ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is 9.6×10339.6 \times 10^{33} years, competitive with the current best limits on the proton lifetime in this channel
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