中医治疗痤疮的临床应用

痤疮,又称为\"粉刺\",是毛囊皮脂腺单位的一种慢性炎症性皮肤病,其发病机理不甚清楚,辨证施治复杂,临床表现以好发于人颜面部、胸背部皮肤的粉刺、丘疹、脓疱、结节,甚至疤痕等多形性皮损为特点。主要好发于青少年,青春期后往往能自然减轻或痊愈。随着社会节奏的加快、饮食或(和)睡眠的失调以及心理压力的剧增,导致痤疮患者越来越多,对患者的心理和社交影响很大,也影响年青人的爱美

均匀设计法筛选茵陈蒿汤抗脂肪肝脂质代谢异常的效应组分

目的:运用均匀设计法筛选茵陈蒿汤抗脂肪肝脂质代谢紊乱的效应组分及其最优剂量配比,探讨揭示复方配伍理论科学内涵的研究方法。方法:将茵陈蒿汤(茵陈、栀子、大黄)进行分组设计,分为6种中药组合,对高脂饮食诱导的大鼠脂肪肝模型进行干预,观察各组大鼠肝脏的病理变化,并以血清三酰甘油(TG)、肝组织TG、血清低密度脂蛋白(LDL)测定作为筛选指标,分析不同作用途径的效应组分及其最优剂量配比。结果:较之正常组,模型组血清TG、LDL和肝组织TG含量均明显升高(P<0.05~0.01),肝组织存在明显脂肪变性;各药物组上述脂肪病理改变程度均明显减轻。根据均匀设计实验逐步回归分析,降低血清TG和降低肝组织TG的效应组分分别是茵陈、栀子。而茵陈与大黄对降低血清LDL有明显疗效,以茵陈0.3g+大黄0.15g为最优剂量组合。结论:茵陈蒿汤通过多途径调节脂肪肝的脂质代谢,其不同作用途径存在特定的效应组分及相应的最优剂量配比

丙烷选择氧化用VPO/SiO_2催化剂的研究

对比研究了VPO和VPO/SiO2 催化剂的结构、表面元素氧化态、还原性及其对丙烷选择氧化反应的催化性能 .与VPO催化剂相比 ,VPO/SiO2 催化剂具有较大的比表面积 ;VPO主要以 (VO) 2 P2 O7的形式高度分散于SiO2 表面 ;VPO/SiO2 催化剂的还原温度较低 ;VPO/SiO2 催化剂与丙烷的相互作用较强 ;在反应条件下 ,VPO/SiO2 催化剂的活性较高 ,但产物丙烯的选择性较低 ,并有丙烯醛等C3含氧化合物生成 .这可能是由于VPO/SiO2 催化剂表面的V与Si发生了相互作用之故 .随着VPO担载量的增加 ,VPO/SiO2 催化剂的比表面积减小 ;催化剂的还原温度略有升高 ,可还原的晶格氧量增加 ;催化剂表面与丙烷的相互作用增强 ;丙烷转化率升高而丙烯选择性降低 ,丙烯醛选择性在 5 %VPO/SiO2 催化剂上最高 .这可能是由于随着VPO担载量的增加 ,催化剂表面晶格氧的密度增大所

丙烷选择氧化用VPO/SiO_2催化剂的研究

对比研究了VPO和VPO/SiO2 催化剂的结构、表面元素氧化态、还原性及其对丙烷选择氧化反应的催化性能 .与VPO催化剂相比 ,VPO/SiO2 催化剂具有较大的比表面积 ;VPO主要以 (VO) 2 P2 O7的形式高度分散于SiO2 表面 ;VPO/SiO2 催化剂的还原温度较低 ;VPO/SiO2 催化剂与丙烷的相互作用较强 ;在反应条件下 ,VPO/SiO2 催化剂的活性较高 ,但产物丙烯的选择性较低 ,并有丙烯醛等C3含氧化合物生成 .这可能是由于VPO/SiO2 催化剂表面的V与Si发生了相互作用之故 .随着VPO担载量的增加 ,VPO/SiO2 催化剂的比表面积减小 ;催化剂的还原温度略有升高 ,可还原的晶格氧量增加 ;催化剂表面与丙烷的相互作用增强 ;丙烷转化率升高而丙烯选择性降低 ,丙烯醛选择性在 5 %VPO/SiO2 催化剂上最高 .这可能是由于随着VPO担载量的增加 ,催化剂表面晶格氧的密度增大所

一种增益自举运算放大器的分析与优化设计

基于开关电容的流水线ADC设计中,运算放大器的建立时间和精度是关键指标。而增益自举运算放大器的建立时间分析比较复杂。本文通过理论推导和模型简化的方法分析其主运放和辅助运放的单位增益带宽及相位裕度对建立时间的影响。提出了一种P型与N型传输函数相同的辅助运放电路,并以此设计了一个高速、低功耗的自举运算放大器

Preparation and Characterization of Sinter-Resistant RhSm2O3/SiO2 Catalyst and Its Performance for Partial Oxidation of Methane to Syngas

以乙酰丙酮铑(Rh(acac)_3)和乙酰丙酮钐(Sm(acac)_3)为前驱体,用浸渍法制备了Rh/SiO_2和Rh-Sm_2O_3/SiO_; 2催化剂。采用原位红外光谱、热重分析、低温N_2吸附、X射线粉末衍射、高分辨透射电子显微镜、H_2-程序升温还原和X射线光电子能谱等实验技术对催; 化剂的制备过程,比表面积和物相以及Rh与Sm_2O_3间的相互作用进行了表征,并以甲烷部分氧化制合成气为目标反应对催化剂的稳定性进行了考察。研究; 表明:以Rh(acac)_3和Sm(acac)_3为前驱体采用简单的浸渍法即可制备出Rh平均粒径为2.3; nm且具有良好抗烧结性能的Rh-Sm_2O_3/SiO_2催化剂。在浸渍过程中乙酰丙酮化合物通过与SiO_2表面羟基形成氢键而负载于载体表面。S; m(acac)_3在SiO_2表面的单层负载量(质量分数)约为31%,对应于Sm_2O_3的质量分数约为15%,只要Sm(acac)_3的质量分; 数低于这一阈值,均可保证分解后生成的Sm_2O_3以高分散形式负载于SiO_2上,且不会因高温(800; °C)焙烧而团聚。高分散于SiO_2表面的Sm_2O_3与Rh之间存在强的相互作用,可显著提高Rh的分散度,防止其在高温反应条件下烧结,进而使低; Rh负载量的催化剂表现出良好的甲烷部分氧化制合成气反应活性和稳定性。Rh/SiO2 and Rh-Sm2O3/SiO2 catalysts were synthesized by the conventional impregnation method using rhodium acetylacetonate (Rh(acac)(3)) and samarium acetylacetonate (Sm(acac)(3)) as precursors. The preparation and catalytic properties, as well as the interaction between Rh and Sm2O3, were characterized in detail by in situ infrared spectroscopy (IR), thermogravimetric analysis (TG), N-2 physisorption (Brunauer-Emmett-Teller (BET) method), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), temperature-programmed reduction (H-2-TPR) and X-ray photoelectron spectroscopy (XPS). The performance of the catalysts for the partial oxidation of methane (POM) to syngas was also investigated. The results showed that a sinter-resistant Rh-Sm2O3/SiO2 catalyst with an average Rh particle size of similar to 2.3 nm could be synthesized using the conventional impregnation method with Rh(acac)(3) and Sm(acac)(3) as precursors. The surface silanol groups of SiO2 acted as the centers to interact with M(acac)(3) (M=Rh, Sm) molecules when SiO2 was impregnated in the M(acac)(3) solution, leading to the formation of a hydrogen-bonded M(acac)(3) layer on the SiO2 surface. In this experiment, the monolayer coverage of Sm(acac)(3) on the SiO2 surface was equal to a Sm(acac)(3) loading (mass fraction) of approximately 31%, which in turn corresponded to a Sm2O3 loading of approximately 15%. When a Sm(acac)(3)/SiO2 sample with Sm(acac)(3) loading below 31% was heated in air to approximately 360?, the monolayer Sm(acac)(3) species decomposed into highly dispersed Sm2O3 species on the SiO2 surface, which displayed superior stability against sintering at high temperature. No aggregation of the Sm2O3 species was observed even when the sample was heated to 800 degrees C in air. The strong interaction between the highly dispersed Sm2O3 and Rh plays a key role in increasing the dispersion of Rh species in the catalyst and preventing the Rh species from sintering under high temperature conditions. This factor should also be responsible for the superior activity and stability of the Rh-Sm2O3/SiO2 catalyst with extremely low Rh loading for the catalytic partial oxidation of methane to syngas.国家重点基础研究发展规划项目（2013CB933102）,国家自然科学基金（21473144,21373168）,国家基础科学人才培养基金项目（J1310024）及教育部创新研究团队项目（IRT_14R31）资

茵陈蒿汤抗游离脂肪酸对HepG2细胞脂毒性作用的效应中药研究

目的:探讨对游离脂肪酸(FFA)诱导人肝癌细胞株(HepG2)细胞脂肪沉积和对肿瘤坏死因子(TNF-α)分泌有显著抑制作用的茵陈蒿汤的效应中药或组合。方法:采用FFA诱导HepG2细胞脂肪沉积和TNF-α分泌的体外细胞模型和药物血清技术,运用数学模型"均匀设计法",根据复方中的3味中药(茵陈、栀子、大黄),选用U7(76)表进行组方设计所得6种中药组合进行干预,以对甘油三酯(TG)及TNF-α的抑制效应作为考察指标,筛选效应中药或组合,并重新区间分组验证。结果:茵陈和栀子在高剂量组合时有显著降低细胞TG及TNF-α含量的效应,与全方无显著性差异,其中单一茵陈也可显著降低细胞TG及TNF-α含量。结论:茵陈及其与栀子的组合是茵陈蒿汤抑制FFA诱导HepG2细胞脂肪沉积和TNF-α分泌作用的效应中药

A Novel Method for Preparation of Activated Alumina

[中文文摘]将结晶氯化铝与柠檬酸及淀粉等造孔剂混合,经直接干燥和焙烧制得了一种无定形活性氧化铝,并通过X射线粉末衍射、N2物理吸附及氨程序升温脱附等手段对活性氧化铝样品进行了表征,探讨了各组分对活性氧化铝样品性质所起的作用.与常规的活性氧化铝制备方法相比,这种制法省去了中和、老化、过滤和洗涤等步骤,缩短制备周期且过程容易控制.活性氧化铝具有适宜且可调节的比表面积和孔径分布,作为载体负载镍金属组分制成负载型催化剂后,对乙苯加氢饱和与加氢裂化表现出较高的催化活性.[英文文摘]A novel and simple method was developed to prepare alumina with suitable specific surface area and pore size distribution. First,AlCl3·6H2O and citric acid were heated without water in a water bath at 90 ℃ with stirring until a homogenous solution was obtained.Then starch was added into is solution.After the solution was dried at 110 ℃ and calcined at indicated temperature, activated alumina was obtained.The activated alumina was characterized by N2 adsorption,X-ray diffraction,and NH3 temperature-programmed desorption. Compared with the usual technology , this novel preparation did not include some steps such as aging , filtering , and washing. Moreover , the specific surface area and pore size distribution of the activated alumina could be controlled and modified by changing the preparation parameters. The supported Ni/ Al2O3 catalyst with the activated alumina as support showed higher activity for hydrogenation and hydrocracking of ethylbenzene.国家重点基础研究发展计划(973计,2004CB217805); 福建省“百千万人才工程”项目; 福建省自然科学基金(U0750016)

MoPO/SiO_2催化剂上丙烷选择氧化制丙烯醛反应机理

考察了丙烷以及丙烷选择氧化反应的有关中间体或其探针分子(如丙烯、烯丙醇、异丙醇和正丙醇)和产物(如丙烯醛、丙酮和丙醛)在MoPO/SiO2催化剂上的反应行为,用以探明该催化剂上丙烷选择氧化制丙烯醛反应的可能路径.结果表明,异丙氧基是MoPO/SiO2催化剂上丙烷选择氧化制丙烯醛反应的主要中间体,异丙氧基脱β-H生成丙烯或脱α-H生成丙酮,而丙烯则经σ-氧烯丙基转化为丙烯醛

Preparation and Characterization of Presulfidation-Free MoNiP/Al_2O_3 Catalyst for Thiophene Hydrodesulfurization

[中文文摘]在Mo-Ni-P-O浸渍液中添加一定量的极性有机物如柠檬酸等,采用共浸渍法制备了一种不需预硫化和焙烧也具有较高加氢脱硫活性的MoNiP/Al2O3催化剂,并用N2吸附、程序升温还原、X射线光电子能谱、红外光谱和元素分析对催化剂进行了表征.结果表明,柠檬酸的添加削弱了金属组分与载体间的相互作用,有利于金属组分在载体表面的分散,且改善了催化剂的还原性,使催化剂在与含硫反应物料接触过程中自发硫化,从而有利于催化剂加氢脱硫活性的提高.[英文文摘]A new type of MoNiP/Al2O3 catalyst for thiophene hydrodesulfurization was prepared by the co-impregnation method, wherein a suitable amount of citric acid was added in the Mo-Ni-P-O impregnation solution. The catalyst exhibits high activity for thiophene hydrodesulfurization under presulfidation- and calcination-free conditions. The catalyst was characterized by N2 adsorption, temperature-programmed reduction, X-ray photoelectron spectroscopy, infrared spectroscopy, and elemental analysis methods. The effect s of cit ric acid on the structure and activity of the MoNiP/ Al2O3 catalyst were studied. The result s show that the addition of cit ric acid weakens the interaction between the active metal components and support , improves dispersion of active metal component s on the support surface , and promotes the reduction and sulfidation of the catalyst by sulfur-containing feedstocks. Therefore, the hydrodesulfurization activity of the catalyst is improved.国家重点基础研究发展计划(973计划, 2004CB217805); 厦门大学科技创新项目(XDKJCX20051002)