Catalytic Behaviors and Stability of Y_2O_3-Modified Ni/SiO_2 for Partial Oxidation of Methane into Synthesis Gas

采用常规浸渍法制备Y_2O_3修饰的Ni/SiO_2催化剂,并考察其催化甲烷部分氧化(POM)制合成气反应性能。结果表明,Y_2O_3的引入减小了金属Ni的粒径,有效提高了Ni在载体表面的分散性,增强了金属Ni与载体SiO_2间的相互作用,从而使催化剂的抗烧结、抗积碳能力,以及催化剂的POM反应性能得以改善。A series of Y_2O_3-modified Ni SiO_2 catalysts were synthesized by a conventional impregnation method.Catalytic performances for the partial oxidation of methane(POM) to synthesis gas were investigated.The addition of Y_2O_3 promotes a decrease in size of Ni particles supported on silica,increased the dispersion of Ni particles,and enhanced the interaction between Ni and silica.These properties gave the catalysts increased anti-sintering and resistance to carbon deposits.The catalytic behaviors of the Ni-based catalysts for POM were significantly improved when Y_2O_3 was introduced.国家自然科学基金(21373169);; 教育部创新团队项目(IRT1036)资助~

VPO催化剂前驱体的溶液法合成和结构研究

VPO polymer β NH 4(VO 2)(HPO 4) was synthesized from the mixture of NH 4VO 3 and NH 4H 2PO 4 in aqueous acidic solution. This hydrogenphosphate vanadate crystallizes in the orthorhombic space group Pbca with a=0.680 60(8) nm, b=0.925 70(5) nm, c=1.773 70(2) nm, V=1.117 5(3) nm 3, Z=8, D c=1.743 g·cm -3 , μ=88.54 cm -1 and R=0.051. The structure is built up from VO 5 square pyramid linked by trans vertices through the bridged oxygen atom to form an one dimensional isolated chain of {VO 2HPO 4} n- nunning along the a axis

不同措施对倾斜柔性圆柱结构涡激振动抑制研究

海洋工程中的立管和系泊缆线等柔性圆柱结构轴线与来流常存在一定倾斜角度。由于轴向二次流的存在,倾斜圆柱涡激振动(VIV)相比于垂直圆柱更为复杂。如何对VIV有效抑制一直是工程界和学术界关注的焦点问题之一。本研究设计了室内拖曳水池模型实验,拖曳速度间隔为0.05m/s,范围为0.05～1.0m/s。观测了螺旋列板和控制杆对大长径比(L/D=350,L为圆柱长度,D为圆柱外直径)柔性圆柱横流向VIV的抑制效果,对比了垂直状态(α=0°,其中α为倾角)和倾斜状态(α=45°)附带抑制装置的圆柱模型振动特性。实验中采用方形截面、螺距/螺高组合为17.5D/0.25D的螺旋列板。控制杆则选取了四根环向均布于圆柱外周的排布方式,控制杆直径比为0.25D,距主体圆柱0.5D。通过在圆柱模型不同空间位置粘贴应变片,获取随时间变化的弯曲应变数据,并运用模态法对位移进行重构。重点分析了横流向应变变化、位移和VIV抑制效率。研究发现:螺旋列板对45°柔性倾斜圆柱涡激振动抑制效果较垂直状态下明显降低,甚至会增大圆柱的振动响应。而四根的多控制杆排列方式在45度倾斜圆柱上仍能保持较好的抑制涡激振动

柠檬酸镍前驱体热分解制备镍酸镁复氧化物纯相

以组成和结构确定的柠檬酸配合物Mg2NiHcit2·10H2O和MgNiHcitH2O2·8H2OH4cit为柠檬酸为前驱体热分解得到Ni和Mg摩尔比分别为1∶2和2∶1的镍酸镁纯相Mg2NiO3和MgNi2O3。粉末衍射实验证实它们是由半径相近、价态相等的Ni2+和Mg2+形成的固溶体

Catalytic Behaviors and Stability of Aerogel Silica-Supported Ni Catalysts for the Partial Oxidation of Methane into Synthesis Gas

以常压有机溶剂置换(A)和溶剂置换-表面改性(b)方式制备的两种SIO2气凝胶(SIO2-A(或b)型气凝胶,记为SIO2-A(Or b)g)为载体,采用常规浸渍法和聚乙烯吡咯烷酮(PVP)添加浸渍法合成不同SIO2气凝胶负载的nI/SIO2催化剂,并考察其催化的甲烷部分氧化(POM)制合成气的反应性能.结果表明,各催化剂的初始反应性能相近,但nI/SIO2-bg的POM稳定性明显较nI/SIO2-Ag的差,而PVP添加制备的催化剂稳定性则获明显改善,nI/SIO2-Ag-PVP、nI/SIO2-bg-PVP上POM稳定性相近.结合X射线衍射(Xrd)、程序升温还原反应(H2-TPr)、高分辨透射电镜(TEM)和brunAuEr-EMMETT-TEllEr(bET)等表征结果的分析发现:(1)SIO2-Ag表面上存在一定量的羟基,可促进亲水性金属物种与其的相互作用,而SIO2-bg表面上基本为有机基团,与亲水性金属物种几乎无作用;(2)PVP的存在可使金属物种进入亲/疏水载体孔道深处,抑制焙烧中载体骨架的收缩和金属颗粒的生长,进而促进金属载体的相互作用.这二者均能有效地提高催化剂的POM反应稳定性.Two types of aerogel silica,denoted as SiO2- A(or B)G are synthesized with either solvent substitution(A) or solvent substitution-surface modification(B) under atmospheric conditions.Aerogel silicasupported Ni catalysts are then prepared via impregnated(IM) and polyvinylpyrrolidone(PVP)-added IM methods,and their performances for the partial oxidation of methane(POM) are investigated.The similar initial catalytic performances(activity and selectivity) are observed over the different Ni/SiO2catalysts.With respect to POM stability,Ni/SiO2-BG is significantly worse than Ni/SiO2-AG,while catalysts with PVP addition(during preparation) exhibit a significant improvement.In this case,Ni/SiO2-BG-PVP is comparable to Ni/SiO2-AG-PVP.We characterize the catalysts with X-ray diffraction(XRD),temperature-programmed hydrogen reduction(H2-TPR),transmission electron microscopy(TEM),and Brunauer-Emmett-Teller(BET) analysis.We find that there are hydroxyls on the SiO2-AG surface that favor their interaction with hydrophilic metal species,while on the SiO2-BG surface there are organic groups that do not interact with hydrophilic metal species.In addition,with the help of PVP,metal species can access the deep pores of hydrophilic/hydrophobic silica gels.Then,the contraction of the silica framework and the growth of metal particles are inhibited during calcinations,enhancing interactions between Ni and the silica gels.These(benefits from surface hydroxyls and PVP) result in significant improvements in the catalysts with respect to POM stability.国家重点基础研究发展计划(973)(2010CB732303); 国家自然科学基金(21033006;21373169); 长江学者和创新团队发展计划(IRT1036)资助~

The first structural examples of tricitratotitanate [Ti(H(2)cit)(3)](2-) dianions

The crystal structures of the mixed-cation compounds Mg-1/2[Ti(H(2)cit)(3)].6H(2)O and (NH4)Mg-1/2[Ti(H(2)cit)(3)].-6H(2)O (H(4)cit = citric acid), which were synthesized by a modified Pechini process, feature three bidentate [(HO2CCH2)(2)C(CO2-)O-] citrato groups that chelate to the titanium atom through their negatively-charged alpha-alkoxyl and alpha-carboxyl oxygen atoms; the other two beta-carboxylic acid groups are free

Effect of sorafenib and celecoxib combination therapy on proliferation of the human cholangiocarcinoma cell line SK-ChA-1 in vitro

目的研究索拉非尼联合塞来昔布在体外对胆管癌细胞株Sk-CHA-1增殖的影响。方法体外培养人胆管癌细胞株Sk-CHA-1,通过MTT法检测索拉非尼单用或与塞来昔布联用时对胆管癌细胞株增殖的抑制作用,WESTErn blOT分析索拉非尼单用或与塞来昔布联用时对胆管癌细胞株内多聚AdP核糖聚合酶(PArP)蛋白表达的影响。结果索拉非尼抑制胆管癌细胞株Sk-CHA-1的增殖并诱导细胞凋亡。索拉非尼联合塞来昔布协同抑制胆管癌细胞株Sk-CHA-1的增殖。塞来昔布使索拉非尼诱导的胆管癌细胞株Sk-CHA-1的凋亡增加。结论索拉非尼联合塞来昔布能协同抑制胆管癌细胞株Sk-CHA-1的增殖,这与塞来昔布使索拉非尼诱导的细胞凋亡增加有关。Objective To investigate the effect of sorafenib and celecoxib combination therapy on proliferation of human cholangiocarcinoma(CC) cells,using the cultured SK-ChA-1 cell line.Methods Inhibition of SK-ChA-1 cell proliferation by sorafenib alone and in combination with celecoxib was studied in vitro using the MTT assay.The anti-neoplastic mechanisms of sorafenib alone and in combination with celecoxib were assessed by Western blot detection of changes in the caspase cleavage substrate poly ADP-ribose polymerase(PARP).Results SK-ChA-1 cells treated with sorafenib alone showed a dose-dependent growth inhibition and degradation of PARP.Combination treatment with sorafenib and celecoxib synergistically increased the growth inhibition effects and enhanced the degradation of PARP.Conclusion Combination treatment with sorafenib and celecoxib results in a synergistic anti-proliferative effect in the human CC cell line SK-ChA-1;the addition of celecoxib enhances sorafenib-induced apoptosis.国家自然科学基金资助项目(81072014

江西南昌西汉海昏侯刘贺墓出土玉器

江西南昌西汉海昏侯刘贺墓（M1）出土玉器[1]约400件（套）,包括约40种器形。全部玉器分散存放在墓室的不同区域（墓室平面图参见本期第5页图一）,表现为不同区域器形有别,具有不同的功能属性。据此特点,本文按出土玉器的不同区域划分,共甄选出具有代表性的38件玉器介绍如下。一西藏椁（一）娱乐用器库共出土玉器13件,其中舞人玉佩、双龙首国家社科基金重大委托项目“海昏侯墓考古发掘与历史文化资料整理研究”(项目编号:16@ZH022)子课题“海昏侯墓出土文物研究”成果之

Preparations of pure alkaline earth molybdate phases from single molecular precursors

The pure phases of alkaline earth molybdates MMoO4, where M=Mg, Ca, Sr or Ba, were synthesized via the calcination of the related citrato oxomolybdate complexes. The mixed metal oxides can be highly dispersed at the atomic level due to the existence of uniform citrato oxomolybdenum precursors in definite composition. The complexing effect helps to produce the fine-grained oxides with particle size in the ultrafine scale(<100 nm) at heat-treatment temperatures below 500 degreesC. The structures of the precursor complexes and the finally heat-treated particles were studied by means of IR, XRD, DSC, DTA and TG techniques. The morphologies of the particles were observed by using the SEM technique. The average particle sizes were calculated to be in the range of 30-50 nm based on X-ray diffraction line-broadening and SEM images, indicating the poor conglomeration of crystallite at low temperatures