934 resultados para Refusal to Treat
Resumo:
About 18% of Uganda’s surface area is covered with water from which about 300,000 metric tonnes of fish are produced. Fish are currently the second most important export commodity generating approximately US$100 million annually. Fish provides 50% of protein diet for the 20 million people translating into per capita consumption of 12 kg. Close to the production system, this figure rises to 50 – 100 kg. It is estimated that fishery-related activities employ at least one million people countrywide (i.e. 5% of the population). Fish exports to regional markets are worth at least US $ 20 million annually. Fish flesh contains an anticholesterol which assists in reducing heart diseases. Some fishes are of medicinal value e.g. haplochromines (Nkejje) are used to treat measles. Most of the fish in Uganda is got from lakes Victoria, Kyoga, Albert and Albert Nile, Edward and George production systems as well as from the 160 minor lakes and rivers and the associated wetland systems. Capture fisheries based in these systems contribute up to 99% of the fish production in Uganda but aquaculture is also picking up. The fishing industry employs up to one million Ugandans
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Following the global stringent legislations regulating the wastes generated from the drilling process of oil exploration and production activities, the management of hazardous drill cuttings has become one of the pressing needs confronting the petroleum industry. Most of the prevalent treatment techniques adopted by oil companies are extremely expensive and/or the treated product has to be landfilled without any potential end-use; thereby rendering these solutions unsustainable. The technique of stabilisation/solidification is being investigated in this research to treat drill cuttings prior to landfilling or for potential re-use in construction products. Two case studies were explored namely North Sea and Red Sea. Given the known difficulties with stabilising/solidifying oils and chlorides, this research made use of model drill cutting mixes based on typical drill cutting from the two case studies, which contained 4.2% and 10.95% average concentrations of hydrocarbons; and 2.03% and 2.13% of chlorides, by weight respectively. A number of different binders, including a range of conventional viz. Portland cement (PC) as well as less-conventional viz. zeolite, or waste binders viz. cement kiln dust (CKD), fly ash and compost were tested to assess their ability to treat the North Sea and Red Sea model drill cuttings. The dry binder content by weight was 10%, 20% and 30%. In addition, raw drill cuttings from one of the North Sea offshore rigs were stabilised/solidified using 30% PC. The characteristics of the final stabilised/solidified product were finally compared to those of thermally treated cuttings. The effectiveness of the treatment using the different binder systems was compared in the light of the aforementioned two contaminants only. A set of physical tests (unconfined compressive strength (UCS)), chemical tests (NRA leachability) and micro-structural examinations (using scanning electron microscopy (SEM), and X-ray diffraction (XRD)) were used to evaluate the relative performance of the different binder mixes in treating the drill cuttings. The results showed that the observed UCS covered a wide range of values indicating various feasible end-use scenarios for the treated cuttings within the construction industry. The teachability results showed the reduction of the model drill cuttings to a stable non-reactive hazardous waste, compliant with the UK acceptance criteria for non-hazardous landfills: (a) by most of the 30% and 20% binders for chloride concentrations, and (b) by the 20% and 30% of compost-PC and CKD-PC binders for the Red Sea cuttings. The 20% and 30% compost-PC and CKD-PC binders successfully reduced the leached oil concentration of the North Sea cuttings to inert levels. Copyright 2007, Society of Petroleum Engineers.
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The unscented Kalman filter (UKF) is a widely used method in control and time series applications. The UKF suffers from arbitrary parameters necessary for a step known as sigma point placement, causing it to perform poorly in nonlinear problems. We show how to treat sigma point placement in a UKF as a learning problem in a model based view. We demonstrate that learning to place the sigma points correctly from data can make sigma point collapse much less likely. Learning can result in a significant increase in predictive performance over default settings of the parameters in the UKF and other filters designed to avoid the problems of the UKF, such as the GP-ADF. At the same time, we maintain a lower computational complexity than the other methods. We call our method UKF-L. ©2010 IEEE.
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Thai pangas, Pangasius hypophthalmus is one of the important aquaculture species in Bangladesh. Over the last few years spectacular development has been taking place in Thai pangas farming in Mymensingh district. Due to availability of easy breeding and culture techniques as well as quick return, more and more people are converting their rice fields into pangas farms overnight. The present study was carried out to examine health and disease status of Thai pangas mainly through clinical, histopathological and bacteriological techniques. In addition, for collecting primary data on disease and health status of Thai pangas and the resultant socioeconomic impacts on rural households, questionnaire interview and participatory rural appraisal tools were used with selected farming households in three upazilas of Mymensingh district. The most prevalent diseases as reported by the farmers were red spot, followed by anal protrusion, tail and fin rot, pop eye, dropsy and gill rot. Other conditions like cotton wool type lesion, ulceration and white spot were reported but with lower incidence. Four isolates of Aeromonas hydrophila were recovered from kidney and lesion of diseased fish. Hemorrhage over the body especially near mouth and caudal region was noticed in the fishes associated with aeromonad infection. Internally, kidney, liver and spleen became swollen and enlarged. The isolates varied with their pathogenicity. All the four isolates were sensitive to Nitrofurantoin, Cotrimoxazole and Tetracycline but were resistant to Amoxycilline. An attempt was made to treat diseased fish with extracts from neem leaf, garlic and turmeric. Recovery of infection was monitored through mortality and histopathology. General histopathological changes of different organs were also studied. Extract from neem (Azadirachta indica) leaf gave better result. Telangiectasis, lamellar hypertrophy and hyperplasia hemorrhage, lamellar fusion, necrosis of lamellar epithelial cells, presence of parasites and their cysts were the major pathology of gills. Hemorrhagic lesion, pyknotic nuclei and melanomacrophage centers (MMC) were found in the liver of fish. Major pathologies in kidney of fish included presence of MMC, necrotic and ruptured kidney tubules, severe haemopoietic necrosis, and hemorrhage. The economic loss due to disease in Thai pangas farming was estimated from the difference between expected production and actual production. On an average, Thai pangas farmers of Mymensingh incur a loss of Tk. 23,104/ha/cycle due to fish disease (3.6% of expected total production). The loss, however, varied with location and size of farms, type of farmers and management practices. The study also highlighted fish health management related problems and recommended further work for the development of user-friendly farmer-oriented fish health management packages.
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The unscented Kalman filter (UKF) is a widely used method in control and time series applications. The UKF suffers from arbitrary parameters necessary for sigma point placement, potentially causing it to perform poorly in nonlinear problems. We show how to treat sigma point placement in a UKF as a learning problem in a model based view. We demonstrate that learning to place the sigma points correctly from data can make sigma point collapse much less likely. Learning can result in a significant increase in predictive performance over default settings of the parameters in the UKF and other filters designed to avoid the problems of the UKF, such as the GP-ADF. At the same time, we maintain a lower computational complexity than the other methods. We call our method UKF-L. © 2011 Elsevier B.V.
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We describe new results on the vibrations of rolling tyres, aimed at noise prediction for tyres of given design on a smooth road surface. This new approach incorporates our existing models, of smooth road-tyre interaction and belt vibration but includes additional features that are required for real tyre patterns. To this end, the model allows variable tread block size and grooves along the belt circumference; the density and angle of these grooves may also vary laterally. The key innovation is to treat the tyre belt as a laterally stacked series of rings, each of which is equipped with a set of viscoelastic springs around its circumference. It is shown how to use this construction to mimic the details of actual tyre patterns and, in conjunction with existing models, predict belt vibrations. The construction is applied to develop a ring discretisation for a real tyre that shows strong lateral variations. It is shown that the vibration amplitude is concentrated on a set of parallel lines in frequency-wavenumber space and that the tread pattern dictates the occurrence and spacing of these lines. Linkage to a boundary element calculation then allows quantification of the influence of tread parameters on radiated noise. Keywords: Vibration, tread pattern, tyre noise. Copyright © (2011) by the Institute of Noise Control Engineering.
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Amplitude demodulation is an ill-posed problem and so it is natural to treat it from a Bayesian viewpoint, inferring the most likely carrier and envelope under probabilistic constraints. One such treatment is Probabilistic Amplitude Demodulation (PAD), which, whilst computationally more intensive than traditional approaches, offers several advantages. Here we provide methods for estimating the uncertainty in the PAD-derived envelopes and carriers, and for learning free-parameters like the time-scale of the envelope. We show how the probabilistic approach can naturally handle noisy and missing data. Finally, we indicate how to extend the model to signals which contain multiple modulators and carriers.
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We have conducted triaxial deformation experiments along different loading paths on prism sediments from the Nankai Trough. Different load paths of isotropic loading, uniaxial strain loading, triaxial compression (at constant confining pressure, Pc), undrained Pc reduction, drained Pc reduction, and triaxial unloading at constant Pc, were used to understand the evolution of mechanical and hydraulic properties under complicated stress states and loading histories in accretionary subduction zones. Five deformation experiments were conducted on three sediment core samples for the Nankai prism, specifically from older accreted sediments at the forearc basin, underthrust slope sediments beneath the megasplay fault, and overthrust Upper Shikoku Basin sediments along the frontal thrust. Yield envelopes for each sample were constructed based on the stress paths of Pc-reduction using the modified Cam-clay model, and in situ stress states of the prism were constrained using the results from the other load paths and accounting for horizontal stress. Results suggest that the sediments in the vicinity of the megasplay fault and frontal thrust are highly overconsolidated, and thus likely to deform brittle rather than ductile. The porosity of sediments decreases as the yield envelope expands, while the reduction in permeability mainly depends on the effective mean stress before yield, and the differential stress after yield. An improved understanding of sediment yield strength and hydromechanical properties along different load paths is necessary to treat accurately the coupling of deformation and fluid flow in accretionary subduction zones. © 2012 American Geophysical Union All Rights Reserved.
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BACKGROUND: Nanomedicine has the potential to revolutionize medicine and help clinicians to treat cardiovascular disease through the improvement of stents. Advanced nanomaterials and tools for monitoring cell-material interactions will aid in inhibiting stent thrombosis. Although titanium boron nitride (TiBN), titanium diboride, and carbon nanotube (CNT) thin films are emerging materials in the biomaterial field, the effect of their surface properties on platelet adhesion is relatively unexplored. OBJECTIVE AND METHODS: In this study, novel nanomaterials made of amorphous carbon, CNTs, titanium diboride, and TiBN were grown by vacuum deposition techniques to assess their role as potential stent coatings. Platelet response towards the nanostructured surfaces of the samples was analyzed in line with their physicochemical properties. As the stent skeleton is formed mainly of stainless steel, this material was used as reference material. Platelet adhesion studies were carried out by atomic force microscopy and scanning electron microscopy observations. A cell viability study was performed to assess the cytocompatibility of all thin film groups for 24 hours with a standard immortalized cell line. RESULTS: The nanotopographic features of material surface, stoichiometry, and wetting properties were found to be significant factors in dictating platelet behavior and cell viability. The TiBN films with higher nitrogen contents were less thrombogenic compared with the biased carbon films and control. The carbon hybridization in carbon films and hydrophilicity, which were strongly dependent on the deposition process and its parameters, affected the thrombogenicity potential. The hydrophobic CNT materials with high nanoroughness exhibited less hemocompatibility in comparison with the other classes of materials. All the thin film groups exhibited good cytocompatibility, with the surface roughness and surface free energy influencing the viability of cells.
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Nostoc sphaeroides Kuetzing has been used as a traditional medicine in China to treat a variety of ailments. This research identified the antioxidant activities of polysaccharide extract from Nostoc sphaeroides. The extract, which contains 46.2% carbohydrates, exhibited an effective scavenging capability on superoxide radical, hydroxyl radicals in non site-specific as well as site-specific assays, and also performed lipid peroxidation inhibition in a dose-dependent manner. Polysaccharide extract had no 1,1-diphenyl-2-picrylhydrazyl radical scavenging potential at all test concentrations. Activities of superoxide dismutase, catalase, and glutathione peroxidase in human embryo kidney 293 cells were increased effectively when Nostoc sphaeroides extract was applied. These results suggested that the use of N. sphaeroides in treating ailments may be based on the antioxidant capacities of polysaccharide composition.
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The annealing behavior of the hexagonal phase content in cubic GaN (c-GaN) thin films grown on GaAs (001) by MOCVD is reported. C-GaN thin films are grown on GaAs (001) substrates by metalorganic chemical vapor deposition (MOCVD). High temperature annealing is employed to treat the as-grown c-GaN thin films. The characterization of the c-GaN films is investigated by photoluminescence (PL) and Raman scattering spectroscopy. The change conditions of the hexagonal phase content in the metastable c-GaN are reported. There is a boundary layer existing in the c-GaN/GaAs film. When being annealed at high temperature, the intensity of the TOB and LOB phonon modes from the boundary layer weakens while that of the E-2 phonon mode from the hexagonal phase increases. The content change of hexagonal phase has closer relationship with annealing temperature than with annealing time period.
Resumo:
本论文由四部分组成,前三部分为实验论文,第四部分为文献综述。第一、二部分分别报道了中药西藏胡黄连和鸡矢藤的化学成分研究结果。从两种药用植物中共分离和鉴定了32个化学成分,其中3个为新化合物。第三部分为黄芪多糖的提取工艺研究。第四部分概述了近年来植物多糖的研究进展。 第一章为西藏胡黄连化学成分研究。通过正、反相硅胶柱层析等分离方法从药用植物西藏胡黄连(Picrorhiza scrophulariiflora Pennell)的根茎中共分离纯化出7个化合物。运用MS、1H-NMR、13C-NMR、DEPT、HSQC和HMBC等现代谱学方法,结合理化分析对这些化合物的结构进行了分析鉴定。7个化合物中有两个是酚性的葡萄糖苷类成分:西藏胡黄连酚苷D (1)、4-O-β-D-(6-O-vanilloyl glucopyranosyl) vanillic acid (6);四个苯乙基苷类化合物:plantamajoside (2)、plantainoside D (3)、西藏胡黄连苷A (4) 和西藏胡黄连苷F (5);一个苯基小分子化合物:香豆酸甲酯 (7)。其中化合物1和5未见文献报道,确定为新化合物;化合物3为首次从该种植物中分到。 第二章为鸡矢藤化学成分研究。从鸡矢藤(Paederia scandense (Lour) Merrill)全草中分离出25个化合物,通过理化常数和波谱数据鉴定了它们的结构。25个化合物中包括一个蒽醌类成分:茜根定-1-甲醚 (1);两个香豆素:异东莨菪香豆素 (2)和5-羟基-8-甲氧基吡喃香豆素 (3);两个香豆素-木脂素化合物:臭矢菜素 B (4)和臭矢菜素 D (5);一个木脂素:异落叶松树脂醇 (6);两个黄酮:diadzein (7)和蒙花苷 (8);三个三萜类化合物:齐墩果酸 (9)、乌苏酸 (10)和 3-O-β-D-吡喃葡萄糖基乌苏烷 (11);三个甾体及其糖苷:b-谷甾醇 (12)、胡萝卜苷 (13)和(24R)-豆甾-4-烯-3-酮 (14);六个小分子化合物:对羟基苯甲酸 (15),咖啡酸 (16),香豆酸 (17),丁烯二酸 (18),3,5-二甲氧基-4-羟基苯甲酸(19),咖啡酸-4-O-β-D-吡喃葡萄糖苷(20);五个环烯醚萜类化合物:鸡矢藤苷 (21),鸡矢藤酸 (22),鸡矢藤酸甲酯 (23),saprosmoside E (24)和paederoside B (25)。其中化合物25未见文献报道,为新化合物。化合物1~8、11、14、15~20为首次从该化合物中分离得到。同时对鸡矢藤中环烯醚萜类化合物做了高效液相-串联质谱(HPLC-MSn)分析,探讨了这类化合物的质谱裂解规律。 第三章为黄芪多糖的提取工艺研究。首先确定了黄芪多糖含量的测定方法,并进行了方法学验证;其次探讨了黄芪中黄芪多糖的提取工艺,确定以酶法-Sevag法联用来去除黄芪多糖中的蛋白质,可使其提取物中黄芪多糖总含量达到70%以上。 第四章为近年来植物多糖的研究进展。主要包括植物多糖的提取纯化、多糖的定性定量检测方法、多糖的结构分析和多糖的药理活性。 This dissertation consists of four parts. The first and second parts reports the studies on the chemical constituents of medicinal plants of Picrorhiza Scrophulariiflora and Paederia scandens. The third part is about the extract technique of Astragalan Polysaccharide (APS). The last part reviews the progress of the studies on plant polysaccharides. The first chapter is about the chemical constituents of P. Scrophulariiflora which is widely used as an important medicine to treat various immune-related diseases. A new phenyl glycoside, scrophenoside D (1) and a new phenylethyl glycoside, scroside F (5), together with five known compounds, plantamajoside (2), plantainoside D (3), scroside A (4), 4-O-β-D-(6-O-vanilloylglucopyranosyl) vanillic acid (6); and methyl-p-coumarate (7) were isolated from the stems of P. scrophulariiflora. Their structures were elucidated by spectroscopic and chemical methods. The second chapter is about the chemical constituents of medicinal herb of P. scandens. Twenty-five compounds were isolated and purified by normal and reversed phase silica gel column chromatography. By physicochemical properties and spectral analysis, their structures were identified as rubiadin-1-methylether (1), isoscopoletin (2), 5-hydroxyl-8-methoxyl-coumarin (3), cleomiscosin B (4), cleomiscosin D (5), isolariciresinol (6), diadzein (7), linarin (8), oleanolic acid (9), ursolic acid (10), 3-O-β-D-glucopyranosyloxyl-ursane (11), b-sitosterol (12), b-daucosterol (13), (24R)-stigmast-4-ene-3-one (14), p-hydroxyl-benzoic acid (15), caffic acid (16), coumaric acid (17), trans-butenedioic acid (18), 3,5-dimethoxyl-4-hydroxylbenzoic acid (19), caffeic acid 4-O-β-D-glucopyranoside (20), paederoside (21), paederosidic acid (22), paederosidic acid methyl ester (23), saprosmoside E (24), paederoside B (25). Among them, compound 25 is a new compound. Compounds 1~8、11、14、15~20 were isolated from this plant for the first time. Futhermore, we studied the HPLC-MSn analysis and investigation of fragmentation behavior of the sulfur-containing iridoid glucosides. The third chapter is about the extracting process of Astragalan Polysaccharide (APS). The method of the content determination is built. The optimum condition of extraction of polysaccharides from Radix Astragali is defined and the more effective way to remove protein is combined enzyme method with Sevag method, by which the content of polysaccharides extract can be up to 70%. The last part is a review of the research progress of the plant polysaccharides, which includes its extraction, isolation, purification, determination, structure analysis, and pharmacology.
Resumo:
本学位论文报道了西藏产三种藏族传统植物药材的化学成分研究。论文由四章组成,前三章是实验部分,分别报道了尼泊尔黄堇(Corydalis hendersonii Hemsl.)、藏波罗花(Incarvillea younghusbandii Sprague)和全缘叶绿绒蒿(Meconopsis interifolia Franch.)的化学成分研究结果。从这三种青藏高原药用植物中共分离鉴定出33 个化合物,其中1 个是新化合物。第四章概述了罂粟科紫堇属植物的化学和药理研究进展。 第一章为尼泊尔黄堇的化学成分研究。通过正、反相硅胶柱色谱等分离方法从药用植物尼泊尔黄堇的地上部分共分离纯化得到12 个化合物。运用MS、1H-NMR、13C-NMR、DEPT、HMBC、NOESY 等现代波谱学方法将它们的结构鉴定为:刺罂粟碱(1) , 普托品(2) , 新那亭(3) , 斯可任(4) , tetrahydrothalifendine (5) ,9-methyl-decumbenine C (6),tetrahydroberberrubine (7),隐品碱(8),α-别隐品碱(9),6,7-methylenedioxy-1(2H)-oxoisoquinolinone (10),6-丙酮基-5,6 -二氢血根碱(11)和β-谷甾醇(12)。其中化合物6 为新化合物,为首次发现的分子骨架上C-9 位连有甲基的苯肽异喹啉类型生物碱。另外,除化合物1 和2 外,其它9 个生物碱(3~11)均为首次从该种植物中分离得到。同时,我们还对对尼泊尔黄堇中的总生物碱进行了串联质谱分析。 第二章为藏波罗花的化学成分研究。从该药用植物的地上部分共分离得到16个化合物,通过理化常数和波谱数据鉴定为:异佛手柑内酯(1),6-甲氧基当归素(2),欧前胡素(3),花椒毒内酯(4),珊瑚菜素(5),水合氧化前胡素(6),rivulobirin A (7),齐墩果酸甲酯(8),咖啡酸甲酯(9),银桦酸(10),(D)-boschniakinic acid (11),对羟基苯甲酸(12) , tert-O-β-D-glucopyranosyl-(R)-heraclenol (13) , 5-methoxy-8-O-β-D-glucopyranosyloxypsoralen (14),前胡苷V(15)和苯乙醇-O-β-D-吡喃葡萄糖-(1→2)-O-β-D-吡喃葡萄糖苷(16)。所有以上化合物均为首次从该种植物中分离得到。另外我们还首次对藏波罗花挥发油的化学成分进行了气相色谱-质谱(GC-MS)联用分析,共鉴定出39 个挥发性成分。 第三章为全缘叶绿绒蒿化学成分的分离鉴定。从传统藏药材全缘叶绿绒蒿地上部分共分离纯化出8 个化合物。通过理化常数和波谱数据将他们的结构分别鉴定为:去甲血根碱(1),β-谷甾醇(2),3-羟基-齐墩果烷-12(13)-烯-30-酸(3),6-丙酮基-5,6-二氢血根碱(4),木犀草素(5),胡萝卜苷(6),quercetin 3-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (7)和普托品(8)。其中化合物1,4 和7 为首次从该种药用植物中分离得到。 第四章为综述,总结和归纳了近年来罂粟科紫堇属植物的化学和药理研究进展。 This dissertation consists of four parts. The first, second and third parts report the studies on the chemical constituents from the medicinal plants of Corydalis hendersonii, Incarvillea younghusbandii and Meconopsis interifolia. The forth part reviews the progress of the studies on Corydalis species. The first chapter is about the isolations and identifications of alkalids from the aerial parts of C. hendersonii which is a traditional Tibetan medicine to treat febrifuge, high blood pressure and hepatitis. A new isoquinoline alkaloid, 9-methyl-decumbenine C (6), together with ten known alkaloids, stylopine (1), protopine (2), canadine (3), scoulerine (4), tetrahydrothalifendine (5), tetrahydroberberrubine (7), cryptopine (8), α-allocryptopine (9), 6,7-methylenedioxy-1(2H)-isoquinolinone (10) and 6-acetonyl-5,6-dihydrosanguinarine (11), and β-sitosterol (12) were isolated. Their structures were elucidated by spectroscopic methods. Furthermore, the total alkaloids were analyzed by ESI-MSn. The second chapter is about the isolations and identifications of chemical constituents from the aerial parts of I. younghusbandii. Sixteen compounds were isolated and purified by normal and reversed phase silica gel column chromatography. By spectral analysis, there structures were identified as isobergapten (1), sphondin (2), imperatorin (3), xanthotoxin (4), phellopterin (5), heraclenol (6), rivulobirin A (7), methyl oleanolate (8), methyl caffeate (9), grevillic acid (10), (D)-boschniakinic acid (11), 4-hydroxybenzoic acid (12), tert-O-β-D-glucopyranosyl-(R)-heraclenol (13), 5-methoxy-8-O-β-D-glucopyranosyloxypsoralen (14), decuroside Ⅴ(15), and phenylethyl-O-β-Dglucopyranosyl-(1→2)-β-D-glucopyranoside (16). All of these compounds were isolated from this plant for the first time.By the way, the chemical components of the essential oil from I. younghusbandii were analyzed by GC-MS for the first time. The third chapter is about the the isolations and identifications of the chemical constituents of M. interifolia. Eight compounds were isolated and identified as norsanguinarine (1), β-sitosterol (2), 3-hydroxyolean-12(13)-en-30-oic acid (3), 6-acetonyl-5,6-dihydrosanguinarine (4), luteolin (5), daucosterol (6), quercetin 3-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (7) and protopine (8). The compounds 1, 4 and 7 were isolated from this herb for the first time. The last chapter is a review of the research progress of the studies on Corydalis species, which includes the chemical constituents in this genus and their pharmacology.
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目前对PVA生物降解研究重点逐渐转移到对PVA降解菌和PVA降解酶的研究开发上,随着对PVA降解高效新菌株的不断发现和PVA降解酶作用机理和分泌机制的深入了解,利用高效微生物或酶法治理PVA这类高聚物的污染将具有较大的应用潜力。本论文研究工作正是基于这种客观条件下进行的,对本实验室前期分离的PVA降解菌株P1、共生菌B1+B2、Pa、Pb为研究对象,重点研究了菌株P1和共生菌B1+B2的产酶条件和产酶特性,验证找出了影响菌株P1产酶的生长因子,论证了菌株B1+B2的产酶特性,优化得出了菌株B1+B2的最佳产酶条件;然后对共生菌B1+B2的PVA降解酶的稳定性进行了研究;最后研究了最佳组合菌的产酶特性和最佳产酶条件。主要研究结果如下: 1 通过对菌株P1产酶因子的研究,找出了核黄素是菌株P1产酶的必须因子,在以淀粉为碳源时,核黄素只是产酶的必须因子,而不是菌体生长的必须因子;在以PVA为碳源时,核黄素既是生长的必须因子,也是产酶的必须因子,是菌株P1的生长因子。 2 对共生菌B1+B2的产酶条件和产酶特性进行了研究,并通过正交实验找出了影响菌株产酶的主要条件和菌株产酶的最佳条件。 3 对共生菌PVA降解酶的稳定性进行了研究,确定了影响酶稳定性的主要理化条件。 4 通过对菌株降解性能的比较,确定菌株Pa、Pb、共生菌、P1的作为组合菌的组成菌,然后通过复配实验确定出菌株的最佳组合为菌株Pa、P1、共生菌,最后通过正交实验确定最佳组合菌的最佳配比。 5对影响组合菌产酶的因素进行了研究,通过正交实验确定了影响组合菌产酶的主要因素和最佳产酶条件。 本文通过对PVA降解菌株产酶条件和特性的研究,旨在为PVA降解菌生产酶制剂及进一步优化PVA降解菌在PVA废水治理中的应用提供理论和应用依据。 Now the PVA-degrading bacteria and polyvinyl alcohol-degrading enzyme are the key studies on the PVA biological degradation. It has great application potential using special bacteria and enzyme to treat pollution of PVA, with some high efficient Strain and enzyme were found. The study of this paper was based on that objective condition. The stain P1, symbiotic bacteria B1+B2, stain Pa and strain Pb were studied .The conditions of enzyme production and enzyme production characteristic of stain P1, symbiotic bacteria B1+B2 were our key study, we tested and verified the growth factor which effected enzyme production of strain P1, demonstrated enzyme production characteristic of symbiotic bacteria B1+B2, optimized and obtained the optimum conditions of enzyme production; then we studied the stability of polyvinyl alcohol-degrading enzyme of strain B1+B2; last the enzyme characteristic and the optimum conditions of alcohol-degrading enzyme production of optimum combination stains were studied. The main study results are below: 1. Through the study of enzyme production factor we found that lactoflavin is the necessary factor in strain P1 enzyme production. When we used starch to be carbon energy, lactoflavin is only the necessary factor of enzyme production, but not growth factor. When we used PVA to be carbon energy, lactoflavin was not only the necessary growth factor ,but also the necessary enzyme production factor.So it was the growth factor of strain P1 2. The enzyme production conditions and enzyme production characteristic of symbiotic bacteria B1+B2 were studied. Through the orthogonal experimental design, the main conditions which effected the enzyme production and the optimum conditions of enzyme production were obtained 3. Through the study of the stability of polyvinyl alcohol-degrading enzyme, the main physical and chemical conditions which effected the enzyme stability were 4. The stain P1,symbiotic bacteria B1+B2, stain Pa and strain Pb were selected to form combination bacteria. The stain P1,symbiotic bacteria B1+B2,stain Pa were the optimum combination through duplication experiment. Then the optimum ratio was obtained through orthogonal experiment. 5. Studied the factors which effected the polyvinyl alcohol-degrading enzyme activity, then through orthogonal experiment, the main factors and condition of enzyme production which effected the combination bacteria were achieved. The result of the study was valuable for the ferment of the PVA-degrading enzyme and the optimization of the PVA-degrading performance in the PVA wastewater.
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钻井废水是油气井开采钻探过程中产生的废水,钻井废水成分复杂,有机物浓度高、色度高、悬浮物浓度高,水质变化大,排放点分散,不经处理排放会污染环境,破坏生态。随着石油工业的不断发展和国家环保法律法规的日益严格,钻井废水的治理也越来越受到重视。如何采用经济有效的方法处理废弃钻井液,对油气井开采业的可持续发展具有重要意义。本论文以遂宁磨153 井的钻井废水为主要研究对象,在对废水进行絮凝沉降预处理和生物法处理探索的基础上,针对钻井废水可生化性差的特点,采用水解酸化和Fenton 试剂改善钻井废水的可生化性,对反应过程进行了比较详细的考察,对可生化性改善的机理进行了探索。主要研究结论如下:1 用PFS 和PAC 配制的混合混凝剂对钻井废水COD 的去除效果比较显著,在最佳条件下COD 的去除率可达75%,且絮体沉降速度较快,出水pH 保持中性;2 水解酸化法处理钻井废水可显著改善废水的可生化性。经48 小时水解酸化处理,钻井废水的理论BOD5可提高约22 倍,表观BOD5/COD值由0.004 提高到0.034。用接触氧化反应器处理经水解酸化处理后的废水,处理效果比较稳定,COD平均去除率达35.5%;3 研究了Fenton反应中各影响因子对废水COD去除率、BOD5/COD的影响并分析其作用机制,确定了最佳条件:初始pH为4.0,H2O2/Fe2+(摩尔浓度比)为20,H2O2/COD(质量浓度比)为1,反应时间为2 个小时。此条件下,废水的COD去除率约为40%,BOD5/COD值从0.002~0.003 提高至0.15~0.2,可生化性得到很大提高。本论文的主要创新点在于:1 以成分复杂、水质变化大的气井钻井废水为研究对象,从理论BOD 和表观BOD 两方面对水解酸化过程中废水可生化性的变化进行了分析;2 对Fenton 试剂改善钻井废水可生化性的过程、主要影响因素进行了比较详细的考察。本论文的研究成果,可为生物法处理钻井废水的深入研究提供理论依据。Drilling wastewater is produced in the process of oil-gas well drilling,because of its complicated composition, high concentrate of organic compound andsuspended solid, high chroma, levity of water quality and decentralization ofdischarge point, it pollutes environment seriously if discharged without treatment.With the development of petroleum industry and the issuing of more strict laws forenvironmental protection, it has been paid more and more attention on drillingwastewater treatment. It is of great importance for the sustainable development ofoil-gas well drilling to treat drilling wastewater by economical and effective methods.In this paper, drilling wastewater of Mo No.153 well in Suining was studied asthe main object. On the basis of research on pre-treatment with flocculant andbiological treatment, and according to the character of poor biodegradability, thedrilling wastewater was treated by hydrolytic acidification and Fenton’s reagent toimprove its biodegradability. The process and mechanism of biodegradabilitychanging were investigated. The primary conclusions are:1 It is effective to treat drilling wastewater with mixing PFS and PAC asflocculant. The removal rates of COD came up to 75% under optimal conditions, thesedimentation rate of flocculation is rapid, and the pH value of treated water remainedneutral;2 The biodegradability of drilling wastewater was highly improved afterhydrolytic acidification process. The theoretic BOD5 of drilling wastewater increasedby 22 times and its detected BOD5/COD ratio increased from 0.004 to 0.034 afterhydrolytic acidification for 48 hours. The wastewater after hydrolytic acidificationwas treated by biological contact oxidation reactor. Stable treatment performance was achieved, and the average removal rates of COD came up to 35.5%;3 The effects of various affection factors on the removal efficiency of COD andBOD5/COD radio in treating drilling wastewater by Fenton’s reagent wereinvestigated and the mechanism was analyzed. The optimal conditions were: initialpH of solution was 4.0, the molar ratio of H2O2 and Fe2+ was 20, the concentrationratio of H2O2 and COD was 1 and the reaction time was 120 min. Under the aboveconditions, the removal efficiency was about 40% and the ratio of BOD5 and CODincreased from 0.002 ¡« 0.003 to 0.15 ¡« 0.2. The biodegradability of drillingwastewater was greatly improved.The innovations of this thesis are:1 The drilling wastewater was taken as the research object which hascomplicated composition and variational water quality, and the changes ofbiodegradability were analyzed from theoretic BOD and detected BOD aspects duringhydrolytic acidification process;2 The biodegradability changing process and primary affection factors of drillingwastewater treating by Fenton’s reagent were investigated.The results of this study could provide theoretic foundation for further researchon biological treatment of drilling wastewater.