970 resultados para ANESTHETICS, Volatile: sevoflurane


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本论文由三部分共四章组成。第一部分介绍丁香化学成分的研究成果,第二部分为升麻的化学成分研究,第三部分综述了环菠萝蜜烷三萜结构和活性关系的研究现状。 第一部分包括第一和第二章。第一章介绍了丁香(Eugenia caryophyllataThunb.)花蕾的化学成分和结构鉴定。采用正、反相硅胶柱层析等各种分离方法,从其乙醇提取物的乙酸乙酯萃取物和正丁醇萃取物中共分离出34 个化合物,它们的结构类型分属黄酮、三萜、鞣质等。其中1 个为新的酚苷类化合物,其结构经波谱分析鉴定为2-O-(6'-O-没食子酰基)-b-D-葡萄糖基苯甲酸甲酯(24),另外还有12 个化合物为首次从该植物中分离得到。第二章介绍了丁香挥发油的气相色谱- 质谱联用( GC-MS )和正丁醇萃取物的高效液相色谱- 质谱联用(HPLC-MS/MS)分析,尝试简单快速地检测丁香挥发油及极性部分的主要化学成分的方法。 第二部分为第三章。本章介绍了传统中药升麻(Cimicifuga foetida L.)根部乙醇提取物化学成分的分离纯化和结构鉴定。通过正、反相硅胶柱层析等分离纯化方法和MS、NMR 等波谱解析技术,共分离鉴定了20 个化合物,主要为环菠萝蜜烷三萜,其中5 个新三萜化合物分别鉴定为cimicidol-3-one(38)、3'-O-乙酰基升麻苷H-1(41)、2'-O-乙酰基升麻苷H-1(42)、(3b,12b,16b)-12-乙酰氧-16,23-环氧-9,19-环羊毛甾烷-22-烯-24-酮3-O-b-D-吡喃木糖苷(44)和升麻碱(54)。新化合物54 为结构新颖的环菠萝蜜烷三萜皂苷生物碱,这是首个发现的具有环菠萝蜜烷三萜骨架的生物碱,也是从升麻属植物中发现的第一个三萜生物碱,它的结构通过多种波谱解析,特别是2D-NMR 的充分应用,并结合化学降解和反应得到证实。此外,还介绍了分离得到的一种具有明显抑制破骨细胞活性的化合物(QS29)的体外活性研究。 第三部分即第四章,综述了升麻属植物中环菠萝蜜烷三萜与其生物活性的构效关系研究现状。 This dissertation consists of three parts. In the first and the second parts, thechemical constituents from the flower buds of Eugenia caryophyllata and therhizomes of Cimicifuga foetida were reported. The third part is a review on astructure-activity relationship of the cycloartane triterpenoid from Cimicifuga species. The first part is composed of two chapters. The chapter 1 is about the isolationand identification of the chemical constituents from the flower buds of E.caryophyllata. A new phenolic glucoside gallate, methyl 2-O-(6’-O-galloyl)-b-D-glucopyranosylbenzoate (24), together with thirty-three known compounds has beenisolated from the ethanol extract of the flower buds of E. caryophyllata throughrepeated column chromatography on normal and reversed phase silica gel. Thestructure of the new compound was elucidated on the basis of spectral and chemicalevidence. Those kno wn compounds were belonged to flavone, triterpenoid, tannin andsome simple compounds. Among them, 12 compounds were isolated from the titleplant for the first time. The second chapter describes the capillary GC-MS analysis ofthe volatile components and the HPLC-MS/MS analysis of the polar constituents fromthe flower buds of E. caryophyllata, in order to detect the main constituents in thecrude extract rapidly and precisely. The third chapter is about the chemical constituents of the rhizomes C. foetida, atraditional Chinese medicine which was used as anti-inflammatory, analgesic andantipyretic agents. Our investigation of the bioactivities constituents of the rhizomesof C. foetida led to the isolation of five new cycloartane triterpenoids, which werecharacterized as cimicidol-3-one (38), 3'-O-acetyl cimicifugoside H-1 (41),2'-O-acetyl cimicifugoside H-1 (42), (3b,12b,16b)-12-acetoxy-16,23-epoxy-9,19-cyclolanost-22-ene-24-one 3-O-b-D-xylopyranoside (44) and cimicifugadine (54),along with fifteen known compounds through repeated column chromatography onnormal and reversed phase silica gel. Among them, 54 is a novel cycloartanealkaloid and first discovered as a new type alkaoid from nature. The structures ofthese compounds were elucidated on the basis of spectral and chemical evidence, andcimicidol-3-one was confirmed by X-ray crystallography analysis. Moreover, onecompound exhibited strong anti-osteoporosis activity in vitro experiment. The fourth part is a review on a structure-activity relationship analysis of thecycloartane triterpenoid from Cimicifuga species.

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环境突发污染事故给人民生活、经济发展和生态环境造成重大影响,研究污染物泄漏造成河流突发污染事故的应急处理方法十分必要。本论文选取苯酚、苯胺和亚甲基蓝等典型污染物为实验对象,采用吸附容量大、密度与水接近的活性炭纤维(ACF)为吸附剂。在自制的河流模型中,研究了ACF以苯酚、苯胺和亚甲基蓝为典型污染物的吸附过程,考察了吸附剂投加量、污染物浓度、吸附剂比表面积、吸附剂投加方式、水流速度与水质等对吸附速率与吸附效果的影响。实验结果表明,ACF能以较快的速率吸附苯酚、苯胺和亚甲基蓝,吸附率都在95%以上; ACF投加量是影响吸附速率最重要的因素,当一次性投加ACF质量之比为 1:2:4时,吸附速率常数之比近似为1:2:4;污染物浓度对吸附速率的影响显著,浓度较低时吸附速率较高。苯酚初始浓度为7mg·L-1时,经过86分钟的吸附,处理后的浓度可以达到地表水Ⅴ类水中挥发酚的限值要求(0.1mg·L-1);在吸附11分钟左右追加适量的ACF,能够明显提高吸附速率;河水流速和河流中的天然有机物、浊度、河水硬度对ACF吸附都不产生显著影响,这说明ACF作为河流突发污染事故应急处理的吸附剂,有广泛的适应性。在实际河水中,ACF对苯酚的吸附过程与在模拟河水中相似,吸附效果显著。实验结果还表明,ACF对苯酚的吸附是放热反应,符合Freundlich模型和Langmuir模型。事故应急处理后,应该及时将吸附了污染物的ACF打捞上来,有利于进行后续处理。 Emergency environmental pollution accidents pose significant impacts on our living, economic development and ecological environment. The study on the approach of emergency control for the contingency caused by leakage of pollutants in rivers is very necessary. In the experiment, phenol, aniline and methylene blue were selected as representative pollutant and activated carbon fiber (ACF) was selected as adsorbent, which has strong adsorption capacity and similar density to water. In the self-made river model, the effects of ACF dosage, pollutant concentration, ACF surface area, ACF adding ways, water flow rate and water quality on adsorption courses were investigated. The experimental results showed that ACF could adsorb pollutant quickly and effectively. The ACF dosage was the most important factor that affected adsorption rate .When the ACF dosage rate was 1:2:4, the constants of adsorption rate was approximately 1:2:4. The effect of pollutant concentrations on the adsorption rate was notable. Faster adsorption rates were achieved at low pollutant concentrations. Phenol concentration reached the limits of volatile phenol in Category Ⅴ surface water (0.1 mg·L-1) after 86 minutes of adsorption with initial phenol concentration of 7 mg·L-1. After 11 minutes of adsorption, certain amount of ACF was added and the adsorption rate was improved significantly. River flow rate and water quality have little effect on the adsorption rate. The adsorption results obtained in actual river water were comparable with that in simulating river water. The results also showed that, ACF on the absorption of phenol is exothermic reaction, witch matched with the Freundlich model and the Langmuir model. After emergency treatment, the ACF absorbed pollutants should be promptly salvaged for follow-up treatment.

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本文从新鲜大熊猫粪便和实验室保存的沼气发酵富集物中筛选得到 4 株厌氧纤维素分解菌B5、C3、D3-2、D4-1,利用这4 株菌预处理秸秆,然后将预处理后的秸秆用本实验室保存的厌氧产氢菌来发酵进行生物产氢。同时还比较研究了:○1 用1% H2SO4、25% NH3 · H2O和12% NaOH对秸秆进行化学预处理;○2 用厌氧纤维素分解菌对秸秆进行生物预处理;○3 化学与生物组合预处理对秸秆发酵生物产氢的影响。实验结果表明:12% NaOH和生物组合预处理后的秸秆发酵产氢效果最好,其产氢量为21.04 mL g-1,是未经预处理秸秆的75 倍;最高氢气浓度为57.3%,是未经预处理秸秆的96 倍;其产氢的最适pH 为4.5 ~ 6.0,最佳底物浓度为45 ~ 55 g L-1;其发酵过程中的挥发性脂肪酸(VFAs)以乙酸和丁酸为主。 本实验筛选到的 4 株厌氧纤维素分解菌株中,B5 和D4-1 在降解纤维素的同时还具有直接以纤维素为底物产氢的功能,因此本文分别对菌株B5 和D4-1 以及二者的组合菌株B5+D4-1 直接利用秸秆为基质发酵生物产氢做了初步探索研究。结果发现:组合菌株发酵产氢的效果以及对秸秆纤维素和半纤维素的降解率要比单菌株好。菌株B5+D4-1 发酵,秸秆的产氢量为11.4 mL g-1,分别是B5 和D4-1 单菌株的1.6 倍和3.1 倍;组合菌株B5+D4-1 发酵的最大氢气浓度为31.6%,分别是B5 和D4-1 单菌株的1.3 倍和2.4 倍。在发酵过程中,组合菌株B5+D4-1 对秸秆纤维素和半纤维素的最高降解率分别为35.0%和11.8%,分别是菌株B5 的1.2 倍和1.1 倍,是菌株D4-1的1.5 倍和1.3 倍。菌株B5,D4-1 以及组合菌株B5+D4-1 发酵过程产生的挥发性脂肪酸(VFAs)均以乙酸为主。菌株B5 单独发酵过程中只检测到乙酸和丁酸,菌株D4-1 单独发酵以及组合菌株B5+D4-1 发酵过程检测到有乙醇、乙酸和丁酸。 The fermentative bio-hydrogen production by anaerobic hydrogen bacteria preserved in our laboratory from the straw which had been pretreated by four anaerobic cellulolytic decomposition strains of B5, C3, D3-2, D4-1 which were isolated and screened from giant panda’s excrement and biogas fermentation enrichments conserved in our laboratory was studied. Besides, the impact of chemical(1% H2SO4、25% NH3·H2O and 12% NaOH), biological (cellulolytic strains of B5, C3, D3-2, D4-1) and chemical-biological combination pretreatment on bio-hydrogen production from straw by fermentation was also comparatively studied. The experiments showed that the best results of bio-hydrogen production were obtained from the straw with 12% NaOH-biological combination pretreatment method, its capability of bio-hydrogen production was 21.04 mL g-1, which was 75 times higher than the straw without pretreatment; the maximum concentration of H2 was 57.3%, which was 96 times higher than the straw without pretreatment; its optimum pH range was 4.5 ~ 6.0, and its optimum range of substrate concentration was 45 ~ 55 g L-1; In the process of fermentation, the main composition of VFAs were acetate and butyrate. Among the four strains of B5, C3, D3-2, D4-1, B5 and D4-1 have the function of hydrogen-producing by cellulose used as substrate when it decompose cellulose, so the preliminary exploration and research on fermentative bio-hydrogen production by B5, D4-1 and B5+D4-1 which directly used straw as substrate was carried out. The results showed that the combination strains of B5+D4-1 was strikingly better than either B5 or D4-1 strain in the fermentative hydrogen production. The hydrogen-production capability of B5+D4-1 was 11.4 mL g-1 which was respectively 1.6 times and 3.1times higher than B5 and D4-1; the maximum hydrogen concentration of B5+D4-1 was 31.6% which was respectively 1.3 times and 2.4 times higher than B5 and D4-1. In the process of fermentation, the maximum degradation rate of cellulose and hemicellulose in straw was respectively 35.0% and 11.8% by B5+D4-1, which was 1.2 times and 1.1 times higher than B5, and was 1.5 times and 1.3 times higher than D4-1 respectively. The Volatile Fattty Acids(VFAs) generated in the process of fermentation with strains of B5, D4-1 and B5+D4-1 were all mainly acetate. Acetate and butyrate were detected in the process of fermentation with B5, ethonal, acetate and butyrate were detected in the process of fermentation with D4-1 and B5+D4-1.

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Based on Monte Carlo method the microscopic gas-phase adsorption chromatographic behaviors of volatile chemical compounds were simulated,and the migration process of those compounds followed by the carrier gases along the chromatographic surface and the process of adsorption-desorption were also described.The programs have been compiled to simulate the processes of thermochromatography and isothermal chromatography with different experimental conditions and properties.The calculated results agree well with ...中文摘要:用蒙特卡罗方法模拟了易挥发化合物的气相色谱微观动力学行为,描述了化合物随气流在固体色谱柱表面的迁移以及吸附-解吸等过程。按气相色谱微观动力学模型编译的计算机程序模拟了超重元素化合物在等温色谱及热色谱的动力学过程,并根据不同实验条件进行了大量计算。计算结果与实验数据较为吻合。讨论了超重元素的半衰期、吸附态的周期、载气流量以及化合物的质量密度等对实验结果的影响及该理论模型的优点和待改进的地方。

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In order to study the gas-phase chemical behavior of transactinides, an on-line isothermal chromatography apparatus has been developed and applied to separate short-lived technetium isotopes in the form of TcO3 from fission products. The fission products from a Cf-252 source were continuously and rapidly transported through the capillary to the isothermal chromatography apparatus using the N-2/KBr gas-jet techniques. Volatile oxide molecules were formed at the reaction zone kept at 900 degrees C since a trace amount of oxygen existed in the N-2 carrier gas. With the new developed isothermal chromatography apparatus, a selective separation of Tc from fission products was achieved. After isothermal chromatographic separation, Tc-101,Tc-103,Tc-104,Tc-105,Tc-106,Tc-107,Tc-108 were dominantly observed together with their Ru daughters in the gamma-spectrum, The chemical yields of Tc-101, and Tc-104 and Tc-105 isotopes with longer half-lives are about 55-57%, and those of Tc-103, Tc-106 and Tc-108 isotopes with shorter half-lives dropped down to 25-28%. The adsorption enthalpy of the investigated compounds on quartz surfaces was determined to be -150 +/- 5 kJ/mol by fitting the measured retention curves with a Monte Carlo model. The observed species of technetium oxide is attributed to TcO3, which is in good agreement with previous experimental results. That means our system worked properly and it can be used to investigate the gas-phase chemical behavior of transactinides.

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本文对ECR离子源强流高电荷态离子的产生、金属离子的产生、强流多电荷态混合离子束的传输做了深入细致的研究。设计建造了一台全新的高电荷态ECR离子源-LECR3(兰州第三台高电荷态ECR离子源),该离子源的目标是产生强流高电荷态离子,设计上应用了多种提高高电荷态离子产额的关键技术:采用了高磁场模式;在保证弧腔内壁处径向磁场的前提下尽量增大弧腔的内径;使用铝制等离子弧腔;应用负偏压技术;新的微波馈入方式。经过调试和优化,其结果达到了国际同类离子源最好水平,其中O7+和Ar11+的束流强度为240eμA,O6+为780eμA,Xe26+为90eμA,Xe30+也有6eμA。目前该离子源已经投入原子物理实验平台供束近两年。进行了金属离子产生的研究,并且成功地为加速器提供了5种金属离子。设计了一种结构紧凑的微小型金属加热炉,经过调试和优化,用炉子加热法在离子源上产生了多种金属的高电荷态离子,其中Ca11+可以达到140eμA,针对该种炉子的缺点又设训一了一种高温炉;用MIVOC(Metallic Ionfrom VOlatile Colnpounds)法调试了镍和铁的离子,其中Fe13+的束流强度为140eμA,为目前国际同类离子源最好水平。提出了一种全新的研究低能强流多电荷态混合离子束传输的方法,包括理论和实验两部分,理论上采用蒙特卡罗方法来模拟离子的传输轨迹,考虑电荷交换和空间电荷效应的影响,自行编写了MCIB计算程序,并进行了初步计算;实验上采用单丝和Wien-Filter探测技术来监测混合束的传输路径和某一截而上的各不同元素种类和不同电荷态离子的密度分布,做了初步实验,并且对计算结果和实验结果做了比较和分析,给出了该类束流的传输特性。

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Soil samples from a Louisiana Barataria Basin brackish marshes were fractionated into acid-volatile sulfides (AVS), HCl-soluble sulfur, elemental sulfur, pyrite sulfur, ester-sulfate sulfur, and carbon-bonded sulfur. Inorganic sulfur composed 13% of total sulfur in brackish marsh soil with HCl-soluble sulfur representing 63–92% of the inorganic sulfur fraction. AVS represented less than 1% of the total sulfur pool. Pyrite sulfur and elemental sulfur together accounted for 8–33% of the inorganic sulfur pool. Organic sulfur, in the forms of ester-sulfate sulfur and carbon-bonded sulfur, was the most dominant pool representing the majority of total sulfur in brackish marsh. Results were compared to values reported for fresh and salt marshes. Reported inorganic sulfur fractions were greater in adjacent marshes, constituting 24% of total sulfur in salt marsh, and 22% in freshwater marshes. Along a salinity gradient, HCl-soluble sulfur represented 78–86% of the inorganic sulfur fraction in fresh, brackish, and salt marsh. Organic sulfur in the forms of ester-sulfate sulfur and carbon-bonded sulfur was the major constituent (76–87%) of total sulfur in all marshes. Reduced sulfur species, except elemental sulfur, increased seaward along the salinity gradient. Accumulation of reduced sulfur forms through sedimentation processes was significant in marsh energy flow in fresh, brackish and salt marshes.

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We report a high molar extinction coefficient metal-free sensitizer composed of a triarylamine donor in combination with the 2-(2,2'-bithiophen-5-yl)acrylonitrile conjugation unit and cyanoacrylic acid as an acceptor. In conjugation with a volatile acetonitrile-based electrolyte or a solvent-free ionic liquid electrolyte, we have fabricated efficient dye-sensitized solar cells showing a corresponding 7.5% or 6.1% efficiency measured under the air mass 1.5 global sunlight. The ionic liquid cell exhibits excellent stability during a 1000 h accelerated test under the light-soaking and thermal dual stress. Intensity-modulated photocurrent and photovolatge spectroscopies were employed along with the transient photoelectrical decay measurements to detail the electron transport in the mesoporous titania films filled with these two electrolytes.

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The substantial crystallization suppression of poly(3-hexylthiophene) (P3HT) in the untreated P3HT:C60 composite film prepared from o-dichlorobenzene (ODCB) solution has been revealed. Besides, the effective conjugation length of P3HT in this composite has been nearly maintained to that in the solution. The different crystallization behaviors of P3HT in its composites with C60 and [6,6]-phenyl C-61 butyric acid methyl ester (PCBM) are mainly attributed to the relative solubility of C60 and PCBM with respect to P3HT in ODCB. The solution to overcome this disadvantage of chain conformation and crystallinity of P3HT in the composite with C60 is thus proposed and finalized by resorting to the addition of low volatile solvent with much higher solubility of C60 than P3HT into the main solvent used, so as P3HT can crystallize before C60 forms crystallites in the solution. The feasibility of this approach has been proven by the improved efficiency of devices based on composites of P3HT and the low cost C60 without resorting to post-treatments.

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As a kind of novel green solvent, Room Temperature Ionic Liquids (RTILs) have been paid ever-increasing attentions in RTIL-based extraction for metal separation, since they have many unique proper-ties, such as non-volatile and non-flammable. The progress of that is mainly composed of the partition properties, mechanisms, defects, overcome methods and forecasts of the processes on the environmental analytical chemistry, has been reviewed.

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Fast analysis of ofloxacin and lidocaine, as bactericide and analgesic or anesthetics, is of clinic importance for understanding the patient's medical process. This paper presented a high throughput, simple analysis method of lidocaine and ofloxacin by capillary electrophoresis coupled with electrochemiluminescence (ECL) using porous etched joint. To shorten the analysis time and to improve the analytical performance, a capillary with 10 cm in length was used as the separation channel. The cyclic voltammograms of Ru(bpy)(3)(2+) with different capillary length at same field strength showed that the porous etched joint eliminated the effect of electrophoretic current on the ECL detection. Following micro total analysis systems (muTAS), some advantages of which this approach has, the fabrication of channel in chip was not needed. Compared with capillary electrophoresis with 40-cm-long capillary, the high sample throughput and low zone broadening may be the main advantage of the present system. Under optimal condition, the detection limits of lidocaine and ofloxacin based on peak height were 3.0 x 10(-8) and 5.0 x 10(-7) mot L-1 and a 60 h(-1) of sampling frequency was obtained.

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Tramadol and lidocaine, used as analgesic and local anesthetic in surgery, are partly excreted by kidney. For the first time, we developed a simple and sensitive method, based on capillary electrophoresis with electrochemiluminescence (ECL) detection by end column mode without joint to monitor tramadol and lidocaine in urine. To eliminate the influence of ionic strength of urine sample, analytes were extracted by ether. Tripropylamine (TPA) was used as internal standard. ne recoveries of tramadol and lidocaine were between 94% and 97% at different levels. The method exhibited the linear range for the tramadol and lidocaine from 1.0 X 10(-7) to 1.0 X 10(-4) mol/L with correlation efficient of 0.998. The relative standard deviation (RSD) was 2.9% and 2.7% (n = 8) for tramadol and lidocaine, respectively. The limit of detection (LOD) was 6.0 x 10(-8) mol/L and 4.5 x 10(-8), mol/L (S/N = 3) for tramadol and lidocaine, respectively. The application for detecting tramadol and lidocaine in urine of patients showed that the method was valuable in clinical and biochemical laboratories for detecting tramadol, lidocaine and other tertiary amine pharmaceuticals for various purpose, such as metabolism investigation.