74 resultados para Choruses, Sacred (Mixed voices, 3 parts), Unaccompanied.
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The first thermodynamic dissociation constants of glycine in 5, 15 mass % glucose + water mixed solvents at five temperatures from 5 to 45-degrees-C have been determined from precise emf measurements of a cell without liquid junction using hydrogen and Ag-AgCl electrodes and a new method of polynomial approximation proposed on the basis of Pitzer's electrolytic solution theory in our previous paper. The results obtained from both methods agree within experimental error. The standard free energy of transfer for HCl from water to aqueous mixed solvent have been calculated and the results are discussed.
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随着化工行业的发展,大量有毒有害难降解有机物随工业废水的排放进入环境,这些物质能够在环境中长期存在、积累和扩散,通过食物链对动植物的生存及人类的健康造成不良影响。本文以苯酚、对氯硝基苯、氯苯和十六烷为模拟污染物,以前期研制的功能菌剂为对象,经过紫外线线诱变筛选出优于出发菌株的功能菌,对诱变后功能菌的理化性能进行了研究,对菌种进行了鉴定,在此基础上,就其相互之间的微生态关系进行研究,为混合发酵提供理论基础,并就其最佳发酵条件及发酵参数进行了研究,最后对发酵产品的性能进行了检测。目前,国内外有关功能菌剂的研究还存在多方面的不足,主要包括:①由于多菌种混合发酵过程较为复杂,各菌之间存在复杂的相互作用,影响因素较多,关于菌种之间的相互关系研究得很少,环境功能菌剂的发酵方法大多采用单独发酵后混合的方式。单独发酵对原材料、设备和能源的利用率较低,对于多菌种制剂发酵,在设备、能源和原材料的方面造成的浪费更大,将会大幅增加菌剂的生产成本,影响多菌种功能菌剂的发展;②功能菌剂生产过程的质量控制方面研究得较少;③功能菌剂产品的稳定性、抗冲击性能研究得较少,对环境微生物制剂的研究主要集中在菌种选育和培养条件优化方面。 通过本论文研究,得到以下主要结论。 (1)在紫外线诱变处理中,用紫外线对发生一定程度退化的出发菌株进行诱变处理后,六株具有高效降解性能的菌株被筛选出来,诱变筛选出的菌株形态和ERIC-PCR指纹图谱与出发菌株相比发生了明显改变;而且诱变后的菌株对目标难降解底物的降解能力均得到改善,其中,FPN、FCB、F14、FEm对目标底物的降解率提高了20%以上;诱变后菌株经过7次连续传代接种后,对目标难降解底物的降解率无显著变化,具有一定的遗传稳定性。并对诱变后的功能菌进行了初步的鉴定,这6株菌都分别是芽孢杆菌。 (2)对诱变后的功能菌相互之间的微生态关系进行了研究,通过抑菌实验、生长量以及基质消耗量的比较,确定它们之间的生长关系是无害共栖关系,可以进行混合发酵。 (3)对该功能菌剂进行发酵培养条件研究,结果表明发酵培养基的最佳成分(g/L):葡萄糖 31.0g/L、玉米粉10.0g/L、磷酸氢二钾1.0g/L、硫酸铵1.1g/L、硫酸镁0.55g/L。通过研究不同的培养条件对菌体生长和降解性能的影响,确定了最佳培养条件:培养基初始pH7.5;最适温度32℃;培养基装液量125mL(250 mL三角瓶),以及培养时间对降解性能的影响,培养20 h的产物对降解最为有利。通过研究添加不同目标污染物对菌体生长和降解性能的影响,确定了添加目标污染物的最佳量以及最佳时间:苯酚投加量:1.125 g/L,对氯硝基苯投加量:0.1 g/L;最佳投加时间为发酵培养开始后4 h。 (4)以摇瓶分批发酵最优条件为基础,对FPN、F10、FCB、FNa、F14 和 FEm进行了摇瓶分批发酵试验。以摇瓶分批发酵试验数据为依据,对功能菌剂分批发酵动力学进行了研究,建立了菌体生长和基质消耗的动力学模型,拟合模型能较好的反映功能菌剂分批发酵过程。 (5)功能菌剂和活性污泥协同作用,可以提高系统的生物降解能力,功能菌剂投加量为2%,新鲜活性污泥3500 mg/L,降解24 h条件下,功能菌剂和活性污泥的协同作用对COD的去除率和对照组相比,最多的提高了36.8%。功能菌剂和活性污泥协同作用以及活性污泥的单独作用,其生物降解过程均符合一级反应动力学过程,功能菌剂和活性污泥协同作用的生物降解动力学方程为:,相关系数97%。采用SBR运行方式,引入功能菌剂的SBR系统明显能够改善和提高生物降解的效率。与仅有活性污泥的系统相比,系统对COD的平均去除率可以提高27.1%,同时,系统的耐负荷冲击以及耐毒害冲击的性能比仅有活性污泥的SBR系统强,特别是负荷冲击对引入功能菌剂的SBR系统影响很小。仅有活性污泥的SBR系统经过负荷冲击和毒害冲击之后,不能恢复到冲击之前的水平,而且系统有效作用时间的周期比引入功能菌剂的SBR系统相比大大缩短,而引入功能菌剂的SBR系统处理效果较为稳定,恢复能力很强。 Along with the development of industries, many recalcitrant organic chemicals have been discharged into natural environments together with wastewaters and can exist in waters, soil and sediments for a long time without degradation. These haz-ardous substances, their byporducts and metabolizabilities can be highly toxic, mu-tagenic and carcinogenic, thereby threatening animals, plants and human health through food chain. Consequently the removal of these compounds is of significant interest in the area of wastewater treatment. In this dissertation, the phenol, hydro-quinone, chlorobenzene and hexadecane treated as the model pollutants, the func-tional microorganism agent was used as the starting strains, they treated with ultra-violet light, and then the mutant strains with high degradation ability were screened out and identified primarily, the relationship between these stains were studied, the medium composition and fermentation conditions were optimized, the degradation ability of the fermented production was tested. The literature survey indicates that the study of the microorganism agent is far from complete and more information is re-quired on following problems. 1, Because of the complexity of relationship in mixed fermentation and the complicated factors, the study is hardly to process.2, There is a lack of information on the quality control of the producing process .3, And there is a lack of information on the stability about the microorganism agent. In this dissertation, the main results of the present study could be summarized as follows: (1)The degenerate starting strains were treated with the ultraviolet light, and six mutant strains with high biodegradation ability were screened out by using the me-dium with selective pressure of model pollutants. The mutant strains had great changes in colonialmorphology and ERIC-PCR fingerprinting. And the mutant strains got obvious advantages over the starting strains in degradation ability and over 20% improvement of removal rates was achieved for FPN、FCB、F14 and FEm. The de-gradation ability of the mutant strains was stable after seven generations. After that, the mutant strains were primarily identified as bacillus respectively. (2) The relationship between these mutant strains was studied. By the compari-son of antibiosis effect, biomass and consumption of substrate, the relationships were neutralism and they could be mixed fermented. (3) The optimized cultivation conditions were as follows: glucose 31.0 g/L, corn power 10 g/L, K2HPO4 1.0 g/L, (NH4)2SO4 1.1 g/L, MgSO4 0.55 g/L, initial pH7.5, temperature 32℃, working volume 125 mL/250 mL, and cultivation time 20h (con-sidering the time effect on degradation ability), adding pollutants phenol (1.125 g/L) and hydroquinone (0.1 g/L) into the broth at 4 h after cultivation. (4) Based on the above optimum condition, the batch fermentation was per-formed with strains FPN, F10, FCB, FNa, F14 and FEm in shake flask. The batch fermentation kinetics was studied based on the experimental data. Two kinetic models were constructed which could reflect the regularity of growth and substrate consump-tion in the process of batch fermentation. (5) The co-operation of functional microorganism agent and activated sludge could raise biodegradation of system by adding some microorganism agent and 3500 mg/L fresh activated sludge. Bioaugumentation by the addition of high effective deg-radation culture enhanced the treatment effect of SBR system and the COD removal rate was increased by 20%-36.8%. Its biodegradation matched first-order dynamical reaction equation, and the reaction equation was ln0.2327.391ct=−+. The micro-organism agent had the effect of optimization to activated sludge micro-ecosystem. The SBR system adding 2% microorganism agent, the average COD removal rate of that was increased by 27.1% and stronger anti-shock ability to load and toxicant were achieved (compared with SBR system just adding activated sludge). Especially the load-shock has barely effect to the SBR system adding microorganism agent. After the load and toxicant shock, the SBR system just adding activated sludge couldn’t come back to original level and the activated sludge micro-ecosystem was frustrated. The applying of microorganism agent increased biological activity and system’s re-sistance ability to load shock and toxicant shock.
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Although respiration of organisms and biomass as well as fossil fuel burning industrial production are identified as the major sources, the CO2 flux is still unclear due to the lack of proper measurements. A mass-balance approach that exploits differences in the carbon isotopic signature (delta(13)C) of CO2 Sources and sinks was introduced and may provide a means of reducing uncertainties in the atmospheric budget. delta(13)C measurements of atmospheric CO2 yielded an average of - 10.3 parts per thousand relative to the Peedee Belemnite standard; soil and plants had a narrow range from -25.09 parts per thousand to -26.51 parts per thousand and averaged at -25.80 parts per thousand. Based on the fact of steady fractionation and enrichment during respiration of mitochondria, we obtained the emission Of CO2 of 35.451 mol m(-2) a(-1) and CO2 flux of 0.2149 mu mol m(-2) s(-)1. The positive CO2 flux indicated the Haibei Alpine Meadow Ecosystem a source rather than a sink. The mass-balance model can be applied for other ecosystem even global carbon cycles because it neglects the complicated process of carbon metabolism, however just focuses on stable carbon isotopic compositions in any of compartments of carbon sources and sinks. (C) 2005 Elsevier B.V. All rights reserved.
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Catalytic NO decomposition on LaSrMn1-x Ni (x) O4+delta (0 a parts per thousand currency sign x a parts per thousand currency sign 1) is investigated. The activity of NO decomposition increases dramatically after the substitution of Ni for Mn, but decreases when Mn is completely replaced by Ni (x = 1.0). The optimum value is at x = 0.8. These indicate that the catalytic performance of the samples is contributed by the synergistic effect of Mn and Ni. O-2-TPD and H-2-TPR experiments are carried out to explain the change of activity. The former indicates that only when oxygen vacancy is created, could the catalyst show enhanced activity for NO decomposition; the latter suggests that the best activity is obtained from catalyst with the most matched redox potentials (in this work, the biggest Delta T and Delta E values).
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A new polyoxometalate [Co(phen)(3)](2)[HPMo4V Mo-4(VI) V-6(IV) M2O44]center dot 4H(2)O (M = 0.78Mo(V)+ 0.22V(IV)) 1 was hydrothermally synthesized and characterized by IR, elemental analyses, X-ray photoelectron spectrum, ESR and single crystal X-ray diffraction. The title compound is in the triclinic space group P (1) over bar with a = 12.0953(7) angstrom, b = 14.0182(6) angstrom, c = 14.6468(7) angstrom, V=2402.55(18) angstrom(3), alpha = 105.134(2), beta = 91.841(3), gamma = 91.401(2), Z = 1, and R-1 (wR(2)) = 0.0617 (0.1701). The compound was prepared from tetra-capped pseudo-Kepin with phosphorus-centered polyoxoanions [PMo8V6M2O44](5-) , [Co(phen)(3)](2+) cations and linked through hydrogen bonds and pi-pi stacking interaction into three-dimensional supramolecular framework. Astudy of the magnetic properties of 1 demonstrates that it exhibits antiferromagnetic coupling interactions.
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A novel mixed-valence molybdenum(IV, VI) arsenate(III), Ni(H2NCH2CH2NH2)(3)[((MoO6)-O-IV)(Mo6O18)-O-VI((As3O3)-O-III)(2)]H2O, hydrothermally synthesized and characterized by single-crystal X-ray diffraction and thermogravimetric analysis. The polyanion cage derives from the Anderson structure, in which the central octahedron was filled up by molybdenum(IV) and it was capped on both sides by a novel As3O63- cyclo-triarsenate(III). The title compound had a high catalytic activity for the oxidation of benzaldehyde to benzoic acid using H2O2 as oxidant in a liquid-solid biphase system. (C) 1999 Elsevier Science B.V. All rights reserved.
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The mixed oxides LaNiO3, La0.1Sr0.9NiO3, La2NiO4 and LaSrNiO4 with perovskite (ABO(3)) and related(A(2)BO(4)) structures were prepared and the adsorption property for NO and the catalytic activity for NO decomposition over these oxidse were also tested. The catalysts were characterized by means of BET surface measurement, chemical analysis, NO-TPD etc.. It was shown that the adsorption amount of NO is correlated with the concentration of oxygen vacancy formed and the adsorption type and strength of NO are related to the valence of metallic ion. Generally there are three kinds of adsorption species, NO-, NO+ and NO on the mixed oxides, among them the negative adsorpion species (NO-) are active for NO decomposition. The weaker the adsorption of oxygen on the catalyst is, the faster the mobility of oxygen is and the easier the redox process takes place in reproducing the active sites in which the oxygen species (O-, O2-) would participate.
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Three series of samples LaMnyCo1-yO3+/-lambda, LaFeyMn1-yO3+/-lambda, and LaFeyCo1-yO3+/-lambda (y = 0.0 to 1.0) with Perovskite structure were prepared by an explosion method different from the generally used ceramic techniques. The variation of crystal
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The chloroplasts, mitochondria, and protoplasm devoid of mature chloroplasts (PMC) of Bryopsis hypnoides Lamouroux were isolated by low-speed and sucrose density centrifugation. The PMC aggregated in artificial seawater, and then protoplasts without mature chloroplasts (PtMCs) were formed. Transmission electron microscopy and cytochemical studies indicated that there were mitochondria, nuclei, vesicles, and other small cell organelles in the PtMCs. Scanning electron microscopy showed that there were holes on the surface of 1-h PtMCs and then fewer holes on the surface of 24-h PtMCs, suggesting that a healing process occurred. The plasma membrane was formed over the surface of the PtMCs. However, the cell wall was not regenerated, and the newly formed PtMCs were ruptured and died in 3 days. Light intensity during alga maintenance before use influenced significantly (one-way ANOVA, P < 0.0001) on the number of PtMCs formed; the highest number of PtMCs was formed at 20A mu mol/(m(2) s). When isolated chloroplasts were transferred into seawater, there were only two or three chloroplasts aggregated together. However, isolated mitochondria and the mixed six layers of cell organelles (separated by sucrose density centrifugation) could not aggregate in the artificial seawater. This indicates that the conjunction of cell organelles is important for their aggregation.
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thermal conduction, and acoustic wave propagation are included. This
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研究了卤化铅调整Tm^3+/Yb^3+共掺碲酸盐玻璃的热稳定性能、Raman光谱和上转换发光光谱,分析了Tm^3+/Yb^3+共掺氧卤碲酸盐玻璃的上转换发光机理.结果发现:混合卤化铅调整Tm^3+/Yb^3+共掺碲酸盐玻璃具有好的热稳定性能、低的声子能量、强的上转换蓝光.这表明混合卤化铅调整Tm^3+/Yb^3+共掺碲酸盐玻璃是一种上转换蓝光激光器的潜在基质材料.
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Er3+-doped lithium-potassium mixed alkali aluminophosphate glasses belonging to the oxide system xK(2)O-(15x)Li2O-4B(2)O(3)-11Al(2)O(3)-5BaO-65P(2)O(5) are obtained in a semi-continuous melting quenching process. Spectroscopic properties of Er3+-doped glass matrix have been analysed by fitting the experimental data with the standard Judd-Ofelt theory. It is observed that Judd-Ofelt intensity parameters-Omega(t)(t=2, 4 and 6) of Er3+ change when the second alkali is introduced into glass matrix. The variation of line strength S-ed[I-4(13/2),I-4(15/2)] follows the same trend as that of the Omega(6) parameter. The effect of mixed alkali on the spectroscopic properties of the aluminophosphate glasses, such as absorption cross-section, stimulated emission cross-section, spontaneous emission probability, branching ratio and the radiative lifetime, has also been investigated in this paper.
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Lithium sodium mixed alkali aluminophosphate glasses of the composition xNa(2)O-(15-x)Li2O-4B(2)O(3)-11Al(2)O(3)-5BaO-65P(2)O(5) (where x=0, 3.75, 7.5, 11.25 and 15 mol%) containing 0.5 mol% Er2O3 were prepared by melt quenching. The absorption spectra of Er3+ were studied from the experimental oscillator strengths and the Judd-Ofelt intensity parameters were obtained. The variations of Judd-Ofelt intensity parameters (Omega(2), Omega(4) and Omega(6)), experimental oscillator strengths of certain excited states of Er3+ and hypersensitive band positions with different mixed alkali content have been discussed in detail. It was found that there were similar effects of mixed alkali on both Judd-Ofelt intensity parameter 02 and the experimental oscillator strength of the hypersensitive transition, I-4(15/2) -> H-2(11/2). No shifts in the peak wavelength of the studied transitions were found in different glasses. (c) 2006 Elsevier B.V. All rights reserved.
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采用石墨电阻加热的温梯法生长了V:YAG晶体,晶体的不同部位呈现两种不同的颜色:浅绿色和黄褐色.通过对比分析不同颜色V:YAG晶体的室温吸收光谱,推断出石墨发热体高温下扩散出来的C可以起到还原作用,提高晶体中V^3+tetra离子的浓度,同时诱导了F心的形成.在1300℃下,对不同颜色的V:YAG晶体进行真空退火处理,发现处于八面体格位中的V^3+离子在热激发作用下与近邻的四面体格位Al^3+离子存在置换反应,由此产生一定浓度的四面体格位V^3+离子.同时,F心在退火过程中被完全消除,释放出来的自由电子被
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The objective of this study was to determine the effect of dietary vitamins A, D-3, E, and C on the gonad development, lipid peroxidation, and immune response of yearling rice field eel, Monopterus albus. A 6-wk feeding trial was designed according to an L-16(4(5)) orthogonal design, in which four vitamins, each at four supplementation levels, were arranged. Sixteen diets were mixed with the different vitamin levels and randomly assigned to 16 groups of fish. Increasing dietary vitamin E supplementation level significantly (P <= 0.05) increased the gonadosomatic index and lowered the serum content of malondialdehyde of rice field eel. Increasing dietary vitamin A and C levels also showed similar effect, but the differences were not statistically significant. Serum immunoglobulin M content increased significantly (P <= 0.01) as dietary vitamin C supplementation levels increased. The concentrations of calcium in bones showed significant (P <= 0.05) trend with vitamin D-3 and A supplementation levels, but the bone phosphorus content was not affected by the dietary vitamin levels.