881 resultados para substance ause
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近年来,我国炼油行业发展迅速,炼油能力全世界第二,炼油行业已成为污染大户。本研究针对炼油废水生物处理中存在的稳定达标难、抗冲击负荷能力差、建设投资与运行成本高等问题,就菌剂强化处理炼油废水中试与工程应用展开了研究,以期为菌剂的工程应用与推广提供理论参考与技术支持;并以炼油废水中的主要特征污染物苯酚为研究对象,考察了不同浓度苯酚冲击下功能菌的响应机制,并以此为指导研制功能菌激活促进剂,考察其对功能菌生物学指标的调控效果,以期为废水生物处理有毒污染物冲击调控提供理论依据与技术支持。 中试研究表明,菌剂强化处理炼油废水,出水COD、NH4+-N 平均值为86.7、7.6 mg/L,其平均去除率较常规生物处理系统分别提高了35.47%、59.28%,其耐受COD、NH4+-N 容积负荷分别高达2.42、0.139kg/(m3·d),具有良好的耐冲击能力。工程应用研究表明,菌剂强化处理炼油废水,出水COD、NH4+-N 平均值分别为85.05、8.4mg/L,其去除率较常规生物处理系统提高了25.1%、28.7%,出水水质各项指标均达到了国家《污水综合排放标准GB 8978-1996》一级排放标准。技术经济分析表明,菌剂强化处理炼油废水在建设成本、运行成本上分别降低38%、49%,具有良好的技术经济优势。 苯酚冲击下功能菌响应机制研究表明:不同浓度苯酚冲击下,生物学指标生物量、脱氢酶酶活、1,2-双加氧酶酶活对冲击都有不同程度的响应,其响应敏感程度为脱氢酶酶活>生物量>1,2-双加氧酶酶活。1,2-双加氧酶酶活与COD 降解率相关性良好,可表征苯酚降解过程,确认为调控重点。以此为指导研制出苯酚降解功能菌抗冲击激活促进剂,可有效调控功能菌对有毒污染物苯酚的降解效果,1000mg/L 苯酚冲击下,经调控,其COD 去除率较对照提高20%,降解时间缩短16%以上。其对生物学指标的调控效果为1,2-双加氧酶酶活>生物量>脱氢酶酶活,验证了功能菌在苯酚冲击下的响应机制。研究表明菌剂强化处理炼油废水切实可行,具有良好的技术经济优势。有毒污染物冲击下废水生物处理系统响应机制研究为抗冲击调控提供了新的研究思路。 Currently, China’s oil refining industry is developing rapidly and has become the second largest all over the world. The oil refining industry is one of the major pollution industries in our country. The pilot scale study and engineering application research were conducted aiming at the problems in refining wastewater such as poor treatment stability and water quality, poor anti-shock capacity and expensive running cost, etc., so as to provide theoretical references and technological supports for the engineering application and popularization of microbial preparation in wastewater treatment. Also, the response mechanism of functional microbe under shock of different phenol concentrations, which is the main pollutants in refinery wastewater, was studied. Based on this result, functional microbe activation accelerator was developed, and the regulation effect of functional microbe biological index under phenol shocking were studied, in order to provide theoretical basis and technological support for regulation of toxic shocking of wastewater biological treatment. The result of pilot scale research indicated: for treatment of refinery wastewater in bioaugmention treatment system of microbial preparation, the COD and NH4+-N average value of effluent was 86.7 and 7.6 mg/L, Comparing with normal biological treatment system, the average removal rates of COD, NH4+-N increased 35.47%,59.28% separately by bioaugmention treatment system, which showed better anti-shocking capacity, the volumetric load r of COD and NH4+-N reached 2.42 kg/(m3·d) and 0.139 kg/(m3·d), respectively. The research on engineering application of refinery wastewater bioaugmentation treatment by microbial preparation indicated:the average concentrations of effluent COD and NH4+-N in the bioaugmentation treatment system were 85.05 and 8.4mg/L, which increased by 25.1% and 28.7% comparing with normal biological treatment system of refinery wastewater, And the effluent quality meets the first grade of discharging standard of National Integrated Wastewater Discharge Standard GB 8978-1996. The economic analysis of technology indicated: the demonstration project of bioaugmentation treatment of refinery wastewater by microbial preparation decreased by 38% in construction cost and 49% in running cost. This technology has economic benefits. The response mechanism of functional microbe under phenol shock indicated: biological index such as the biomass concentration, dehydrogenase and 1,2-dioxygenase had different responses under phenol shocking of different concentrations. The response sensitivity of different biological index under phenol shocking of different concentrations is: dehydogenase activity > biomass >1,2-dioxygenase activity, and high correlation of 1,2-dioxygenase and COD degradation percentage is achieved, thus 1,2-dioxygenase could be used to reflect the degradation situation of pollutants. So, 1,2-dioxygenase is the keypoint of regulation. The anti-shock activation accelerator of phenol degradation functional microbe was primarily developed. The results indicated: the activation accelerator could regulate the degradation effect of toxic substance-phenol by functional microbe effectively. For the functional microbe treatment system under phenol shocking of 1000mg/L, the COD degradation rate increased by 20% and the degradation time reduced by more than 16% under regulation of activation accelerator. The regulation effects of biological index are: 1,2-dioxygenase > biomass > dehydrogenase. In this way, the response mechanism of functional microbe under toxic shocking is verified. The result indicated: the augmented microbial preparation treatment of refinery wastewater is applicable. It has many technical and economical advantages. The research results of responses mechanism of wastewater treatment system on toxic pollutants would offer a new idea for regulation of anti-shock.
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Low-temperature heat capacities of the 9-fluorenemethanol (C14H12O) have been precisely measured with a small sample automatic adiabatic calorimeter over the temperature range between T = 78 K and T = 390 K. The solid-liquid phase transition of the compound has been observed to be T-fus = (376.567 +/- 0.012) K from the heat-capacity measurements. The molar enthalpy and entropy of the melting of the substance were determined to be Delta(fus)H(m) = (26.273 +/- 0.013) kJ (.) mol(-1) and Delta(fus)S(m) = (69.770 +/- 0.035) J (.) K-1 (.) mol(-1). The experimental values of molar heat capacities in solid and liquid regions have been fitted to two polynomial equations by the least squares method. The constant-volume energy and standard molar enthalpy of combustion of the compound have been determined, Delta(c)U(C14H12O, s) = -(7125.56 +/- 4.62) kJ (.) mol(-1) and Delta(c)H(m)degrees(C14H12O, s) = -(7131.76 +/- 4.62) kJ (.) mol(-1), by means of a homemade precision oxygen-bomb combustion calorimeter at T = (298.15 +/- 0.001) K. The standard molar enthalpy of formation of the compound has been derived, Delta(f)H(m)degrees (C14H12O, s) = -(92.36 +/- 0.97) kJ (.) mol(-1), from the standard molar enthalpy of combustion of the compound in combination with other auxiliary thermodynamic quantities through a Hess thermochemical cycle. (C) 2004 Elsevier Ltd. All rights reserved.
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本文通过生物追踪实验法 ,研究了鸡粪中有机酸的生物活性成分 ,并从中筛选出了一种强活性物质 .通过红外光谱和质谱及生源关系初步确定其分子式为C36H56O18Na,名称为 3-O -D -葡萄糖 -6,1 -0 -葡萄糖酸 2 β ,2 ,2 0 -二羟基蛋甾酸钠
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In this report, matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) was used to study the binding interactions between calmodulin and two target peptides (melittin and substance P). Various matrix conditions were tested and the less acidic matrix DHAP and THAP were found to favor the survival of the intact calcium-calmodulin as well as the calmodulin-peptide complexes. However, the application of direct MALDI-MS to detect the intact complexes turned out to be very difficult due to the dissociation of the complexes and the formation of nonspecific aggregates. In contrast, the specific binding of the target peptides to calmodulin could be easily deduced using intensity-fading (IF) MALDI-MS. Compared with the nonbinding control, clear reduction in the ion abundances of the target peptides was observed with the addition of calmodulin.
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Sialic acid and lysine as an internal standard substance,the ESI-MS fingerprinting of extracts of Compound Indigowoad Root Granule which from different origin was studied.The fingerprinting was obtained with better precision and reproducibility.This work can provide a reference for the quality control of Compound Indigowoad Root Granule.
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The electrochemiluminescence (ECL) in the S2O82- system occurs under conventional cyclic voltammetry, when the Pt working electrode was coated with Cd elementary substance. The ECL mechanism was proposed, due to the reaction between the strongly oxidizing intermediate SO4 center dot- and the transitory production, CdO, generated by oxidation of Cd with SO4 center dot-. Moreover the ECL behavior was studied in different pHs and concentrations of S2O82- solution. It was showed that the ECL signal was strongest at pH 8.0, and its intensity increased with S2O82-. The experimental results verified well with the proposed ECL mechanism.
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The electrochemical behavior of catechol, hydroquinone and resorcinol on GC and PPy/GC electrode surface were studied by CV and RDE method. The results indicated that these three substance could be oxidized electrocatalytically on PPy film electrode. The possibility of fabrication of amperometric electrochemical sensor for catechol was also studied.
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The corrosion behaviour of titanium substance and the XPS characterization of Ti surface in the H2C2O4 solution have been first studied by X-ray photoelectron spectroscopy, The experimental results show that there am mile Ti-2 and Ti2+ on sample surface in 10% H2C2O4 solution for two boars corrosion at 80 degrees C, but if corrosion is extended to 4 hones, the surface composition is mainly TiO2 with a small amount of Ti2+. This result corresponds to the structure of TiH1.642 composion in sample surface found by XRD analysis. Since bath TiO2 and the surface coating RuO2 are of Gald-Redstone structure, therefore electrode materials of Ti-Ru are stable in chemical industry.
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Coral bleaching, which is defined as the loss of colour in corals due to the loss of their symbiotic algae (commonly called zooxanthellae) or pigments or both, is occurring globally at increasing rates, and its harm becomes more and more serious during these two decades. The significance of these bleaching events to the health of coral reef ecosystems is extreme, as bleached corals exhibited high mortality, reduced fecundity and productivity and increased susceptibility to diseases. This decreased coral fitness is easily to lead to reef degradation and ultimately to the breakdown of the coral reef ecosystems. Recently, the reasons leading to coral bleaching are thought to be as follows: too high or too low temperature, excess ultraviolet exposure, heavy metal pollution, cyanide poison and seasonal cycle. To date there has been little knowledge of whether mariculture can result in coral bleaching and which substance has the worst effect on corals. And no research was conducted on the effect of hypoxia on corals. To address these questions, effects of temperature, hypoxia, ammonia and nitrate on bleaching of three coral species were studied through examination of morphology and the measurement of the number of symbiotic algae of three coral species Acropora nobilis, Palythoa sp. and Alveopora verrilliana. Results showed that increase in temperature and decrease in dissolved oxygen could lead to increasing number of symbiotic algae and more serious bleaching. In addition, the concentration of 0.001 mmol/L ammonia or nitrate could increase significantly the expulsion of the symbiotic algae of the three coral species. Except for Acropora nobilis, the numbers of symbiotic algae of other two corals did not significantly increase with the increasing concentration of ammonia and nitrate. Furthermore, different hosts have different stress susceptibilities on coral bleaching.
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Porphyra yezoensis Ueda (Rhodophyta) is a seaweed of economic importance with a typical dimorphic life cycle consisting of a leafy gametophyte and a filamentous sporophyte. Recently, it has been recognized as a model system for fundamental and applied studies in marine biological sciences. Conchospore, a major spore linking the two distinct multicellular phases in the life cycle, is most widely used in the breeding of P. yezoensis. In this paper, the early-stage development of conchospore, including the attachment and the cell wall formation, was studied with fluorescent reagents staining and Scanning Electron Microscopy detection. Results displayed: (I) the cell wall began to be generated after culturing for 4 h in the attached conchospores; (2) the initially released conchospores were plastids with some filmy, amorphous substance on the surface, and they attached to the fibers firmly via the actively secreted mucilaginous substances after their touch to the fibers; (3) cellulase and pectolase prohibited the attachment of conchospores in the different ways; and (4) only attached conchospores generated cell walls and developed normally, while the suspending ones could not. It indicated that the cellulose played crucial roles in the permanent attachment as the pectin did in the initial attachment. The conchospore attachment seemed to trigger the cell wall formation and the further development. Affects of light on the development of conchospores were also discussed. The results showed that high intensity (200 mu mol.m(-2).s(-1)) and long-wave (>= 580 nm) light facilitated the division rate of conchospores. (C) 2008 Elsevier B.V. All rights reserved.
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Using guanidine-HCl extraction, acetone precipitation, ultra-filtration and chromatography, a novel polypeptide with potent anti-angiogenic activity was purified from cartilage of the shark, Prionace glauca. N-terminal amino acid sequence analysis and SDS-PAGE revealed that the substance is a novel polypeptide with MW 15500 (PG155). The anti-angiogenic effects of PG155 were evaluated using zebrafish embryos model in vivo. Treatment of the embryos with 20 mu g/ml PG155 resulted in a significant reduction in the growth of subintestinal vessels (SIVs). A higher dose resulted in almost complete inhibition of SIV growth, as observed by endogenous alkaline phosphatase (EAP) staining assay. An in vitro transwell experiment revealed that the polypeptide inhibited vascular endothelial growth factor (VEGF) induced migration and tubulogenesis of human umbilical vein endothelial cells (HUVECs). Exposure of HUVECs in 20 mu g/ml PG155 significantly decreased the density of migrated cells. Almost complete inhibition of cell migration was found when HUVECs were treated with 40-80 mu g/ml PG155. PG155 (20 mu g/ml) markedly inhibited the tube formation of HUVECs and a dose-dependent effect was also found when treatment of HUVECs with PG155 at the concentration from 20 to 160 mu g/ml.
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浅海波浪、潮汐风暴潮相互作用的研究是当今国际热点研究方向之一.该项研究针对典型浅海海域渤海,研究了在这个海域的波浪、潮汐风暴潮的相互作用以及物质输运规律.建立了一个渤海波浪和潮汐风暴潮运动相互作用的数值模式.模式主要由两部分组成:一个物理上先进的第三代浅海波浪数值模式和一个二维潮汐风暴潮数值模式,实现了两个模式耦合.运用这个模式,重点研究了波浪对表面拖曳系数的影响;波浪对底摩擦应力的作用;辐射应力对潮汐风暴潮水位的影响以及潮汐风暴潮对波浪的作用.在这个基础上,对物质输运规律进行了研究.
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Under laboratory conditions, the potential influence of diatom diets on reproduction of zoo-plankton Calanus sinicus was studied. Four diatom diet ingredients: Skeletonema costatum (SC), Chaetoceros muelleri (CM), Phaeodactylum tricornutum (PT), diatom mixture (MIX) and a control diet: the flagellate Platymonas subordiformis (PS), were used at the same carbon concentrations of 2.0 mu g mL(-1) C. In a period of 17-day laboratory experiment, the effects of these algae diets on egg production and hatching success of the copepod Calanus sinicus were examined. The diets were analyzed for fatty acid content as an indicator of food quality. The results showed that the female survival of all treatments reached more than 80% except PT. Comparing to the initial value, egg production of Calanus sinicus was reduced in diatom diets (PT, CM), but remained in normal level in SC and MIX, indicating that some single diatom diets had a negative effect on the egg production of Calanus sinicus. Feeding with mixed food however can eliminate this negative effect. Among all the treatments, hatching success in filtered seawater was significantly higher than in algal exudates, indicating that not only diatoms but also other phytoplankton in certain concentration can release extracelluar substance that may inhibit eggs from hatching. Fatty acid analysis showed that both egg production rate and hatching success were negatively correlated to the ratio of 20:5 omega 3 and 14:0 in fatty acid composition.
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Interactions between Prorocentrum donghaiense and Alexandrium tamarens, two bloom-forming dinoflagellates, were investigated using bi-algal cultures. All R donghaiense died, but A. tamarense was hardly affected by the end of the experiment when the initial cell density was set at 1.0 X 10(4) cells mL(-1) for P. donghaiense and 0.28 x 10(4) cells mL(-1) for A. tamarense. However, significant growth suppression occurred in either species when the initial cell density of P donghaiense increased to I. 0 X 105 Cells mL(-1) in the bi-algal culture, but no out-competement was observed. The simultaneous assay on the culture filtrates showed that P donghaiense filtrate prepared at a lower initial density (1.0 X 10(4) cells mL(-1)) stimulated growth of the co-cultured A. tanzarense (0.28 x 10(4) cells mL(-1)), but filtrate at a higher initial density (1.0 x 10(5) cells mL(-1)) depressed its growth. The filtrate of A. tamarense at a density of 0.28 x 10(4) cells mL(-1) killed all R donghaiense at a lower density (1.0 x 10(4) cells mL(-1)), but only exhibited an inhibitory effect on it at a higher density (1.0 x 10(5) cells mL(-1)). It is likely that these two species of microalgae interfere with each other mainly by releasing allelochemical substance(s) into the culture medium, and a direct cell-to-cell contact was not necessary for their mutual interaction. The allelopathic test further proved that A. tamarense could affect the growth of co-cultured P. donghaiense by producing allelochemical(s); moreover, A. tamarense culture filtrate at the stationary growth phase (SP) had a strongly inhibitory effect on P donghaiense compared to that at the exponential phase (EP). Results also demonstrated a dose-dependent relationship between the microalgal initial cell density and the degree of the allelopathic effect. The growth of R donghaiense and A. tamarense in the bi-algal cultures was simulated using a mathematical model to quantify the interaction. The estimated parameters from the model showed that the inhibition exerted by A. tamarense on P. donghaiense was about 17 and 8 times stronger than the inhibition P. donghaiense exerted on A. tamarense, when the initial cell density was set at 1.0 X 10(4) and 1.0 X 10(5) cells mL(-1) for P donghaiense, respectively. and 0.28 x 10(4) cells mL(-1) for A. tamarense in the bi-algal cultures. A. tamarense seems to have a survival strategy that is superior to that of P. donghaiense in bi-algal cultures under controlled laboratory conditions. (c) 2006 Elsevier B.V. All rights reserved.
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Bayan Obo giant REE-Nb-Fe deposit in the northen margin of the North China Craton (NCC) is well known in the world for its abundant rare earth element resources. There is nearly one hundred year of studying history in substance component, chronology and geochemistry of the ore deposit, since the main ore body was found in 1927. However, there still exist remarkable divergences in genesis, mineralized age and material origin. Especially the REE enrichment mechanism leaves us a secret. Recent research shows that the Bayan Obo ore deposit likely resulted from the carbonatite magma activity, which is a favorable factor for REE accumulation. Based on the analysis of tectonic evolution history of north margin of NCC this thesis mainly discussed the formation background of cratonic margined rifts in Bayan Obo, and presented the analytical results of formation environment, intrusion age and deep origin of Proterozoic carbonatite magma. These research results can provide evidence for ore genesis. LA ICP-MS U-Pb dating on zircon shows that the Neoarchean basement was mainly composed of calc-alkaline TTG gneisses (2588±16Ma). The collision orogeny movement of the northen margin of the NCC between 2.0 Ga to 1.9 Ga brought the swarm of diorite-granodiotite magma (2023±16Ma) and intense regional metamorphism event (1906.3±7.7 Ma to 1892.7±6.7 Ma). In the sequent super continent break up background, intense metamorphic and deformed basement complex was uplifted to the surface suffered denudation, forming Mesoproterozoic Bayan Obo group in the contemporary continental margin rifts. The uplift of basement complex and formation of continental rifts were likely related with mantle plume activity. Evidence from petrological and geochemical data suggests that abundant alkaline-basic magma resulted from enhancement of continental breakup activity, that separated into carbonatite veins and mafic dykes by melt immiscibility mechanism, intruded in Bayan Obo margin rifts at the late stage of extension movement. Carbonatite veins can be divided into three main types by mineral composition: dolomite carbonatite, dolomite-calcite coexistent carbonatite and calcite carbonatite. Intrusion relationship between different types of carbonatite veins show that the calcite carbonatite veins were formed latter than the dolomite type as well as the coexistent type. Moreover, geochemical data also reveals successive and evolutive character between them. The content of REE increases together with the calcite minerals component. That is to say that REE gradually accumulated as the evolution of carbonatite magma. High precision Sm-Nd isochron data shows that the intrusion age of carbonatite veins was at 1319±48Ma. Moreover, the REE mineralization age in calcite carbonatite veins was around 1275±87Ma that is consistent with the intrusion age in error range. According to these data the abundant REE already existed in the carbonatite magma before intrusion and result in the earlier ore mineralization. The average age of mineralized dolomite was at 1353±100Ma, and the mineralization age of apatite in coarse grain dolomite was around 1329±150Ma. These data is consistent with carbonatite. Considering the coincident rare, trace element and isochron composition between them, it is presumed that mineralized dolomite was also the carbonatite intrusion and was the mainly factor for huge REE enrichment.