272 resultados para Tauberian Constants


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The electronic properties of wide energy gap zinc-blende structure GaN, AlN and their alloys Ga1-xAlxN are investigated using the empirical pseudopotential method. Electron and hole Effective mass parameters, hydrostatic and shear deformation potential constants of the valence band at Gamma and those of the conduction band at Gamma and X are obtained. The energies of Gamma, X, L conduction valleys of Ga1-xAlxN alloy versus Al fraction x are also calculated. The information will be useful for the design of lattice mismatched heterostructure optoelectronic devices in the blue light range.

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GaP/Si is a promoting heterostructure for Si-based optoelectronic devices since lattice constants of GaP and Si are so closed that they can match with each other. GaP was successfully grow on (100) Si subtracts by Gas-Source Molecular Bean Epitaxy (GS-MBE) in the study. The GaP/Si heterostructure was characterized by X-ray double crystal diffraction, Anger electron spectrograph, X-ray photonic spectrograph and photoluminescence (PL) measurements. The results showed that the epitaxial GaP layers are single crystalline, in which a parallel to and a (perpendicular to)are 0.54322 and 0.54625 nm, respectively. The peaks in PL spectra of GaP epitaxial layer grown on Si are 650, 627 and 640 nm, respectively. The study demonstrated that GaP/Si is a kind of lattice matched heterostructures and will be a promoting materials for future integrated photonics.

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The crystallographic and intrinsic magnetic properties of hydride R3Fe29-xTxHy (R=Y, Ce, Nd, Sm, Gd, Tb, and Dy; T=V and Cr) have been investigated. The lattice constants and the unit cell volume of R3Fe29-xTxHy decrease with increasing R atomic number from Nd to Dy, except for Ce, reflecting the lanthanide contraction. Regular anisotropic expansions, mainly along the a- and b-axis rather than along the c-axis, are observed for all the compounds upon hydrogenation. Hydrogenation leads to an increase in Curie temperature. First-order magnetization processes (FOMP) occur in magnetic fields of around 1.5 T and 4.0 T at 4.2 K for Nd3Fe24.5Cr4.5H5.0 and Tb(3)Fc(27.0)Cr(2.0)H(2.8), and around 1.4 T at room temperature for Gd3Fe28.0Cr1.0H4.2 Abnormal crystallographic and magnetic properties of Ce3Fe29-xTxHy suggest that the Ce ion is non-triply ionized.

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A kind of Faraday glass with a size of 40 mm x 14 mm and 100-300 mm x 25 mm, respectively, was prepared by the melting and casting process, which had neither a Pt particulate nor a bubble or striation. The measurement results showed that the surface homogeneity of the samples was up to +/- 1 x 10-6, the laser threshold reached 10 J/cm2 (1 omega, 3 ns), and the Verdet constants of the glasses were -0.273 min/Oe/cm at 632.8 nm and -0.076 min/Oe/cm at 1064 nm, respectively.

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Nano-fibrillar adhesives can adhere strongly to surfaces as a gecko does. The size of each fiber has significant effects on the adhesion enhancement, especially on rough surfaces. In the present study, we report the size effects on the normal and shear strength of adhesion for a single viscoelastic fiber. It is found that there exists a limited region of the critical sizes under which the interfacial normal or tangential tractions uniformly attain the theoretical adhesion strength. The region for a viscoelastic fiber under tension with similar material constants to a gecko's spatula is 135-255 nm and that under torque is 26.5-52 nm. This finding is significant for the development of artificial biomimetic attachment systems.

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This study experimentally explored the fine structures of the successive period-doubling bifurcations of the time-dependent thermocapillary convection in a floating half zone of 10 cSt silicone oil with the diameter d (0)=3.00 mm and the aspect ratio A=l/d (0)=0.72 in terrestrial conditions. The onset of time-dependent thermocapillary convection predominated in this experimental configuration and its subsequent evolution were experimentally detected through the local temperature measurements. The experimental results revealed a sequence of period-doubling bifurcations of the time-dependent thermocapillary convection, similar in some way to one of the routes to chaos for buoyant natural convection. The critical frequencies and the corresponding fractal frequencies were extracted through the real-time analysis of the frequency spectra by Fast-Fourier-Transformation (FFT). The projections of the trajectory onto the reconstructed phase-space were also provided. Furthermore, the experimentally predicted Feigenbaum constants were quite close to the theoretical asymptotic value of 4.669 [Feigenbaum M J. Phys Lett A, 1979, 74: 375-378].

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Surface initiated polymerization (SIP) is a valuable tool in synthesizing functional polymer brushes, yet the kinetic understanding of SIP lags behind the development of its application. We apply quartz crystal microbalance (QCM) to address two issues that are not fully addressed yet play a central role in the rational design of functional polymer brushes, namely quantitative determination of the kinetics and the initiator efficiency (IE) of SIP. SIP are monitored online using QCM. Two quantitative frequency-thickness (f-T) relations make the direct determination and comparison of the rate of polymerization possible even for different monomers. Based on the bi-termination model, the kinetics of SIP is simply described by two variables, which are related to two polymerization constants, namely a = 1/(k (p,s,app)-[M][R center dot](0)) and b = k (t,s,app)/(k (p,s,app)[M]). Factors that could alter the kinetics of SIP are studied, including (i) the molecular weight of monomers, (ii) the solvent used, (iii) the initial density of the initiator, (iv) the concentration of monomer, [M], and (v) the catalyst system (ratio among the ingredients, metal, ligands, and additives). The dynamic nature of IE is also described by these two variables, IE = a/(a + bt). Instead of the molecular weight and the polydispersity, we suggest that film thickness, the two kinetic parameters (a and b), and the initial density of the initiator and IE be the parameters that characterize ultra-thin polymer brushes. Besides the kinetics study of SIP, the reported method has many other applications, for example, in the fast screening of catalyst system for SIP and other polymerization systems.

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环糊精(Cyclodextrins, CDs)经化学修饰后可以得到各种类型的衍生物,不仅可以扩展其原有的键合能力,而且还可以改变其选择性,是当代超分子化学的一个研究热点。环糊精第二面的仲羟基比第一面的伯羟基有着更好的催化性能,第二面的选择性修饰将产生更多有价值的衍生物,可用于催化、酶模拟、手性识别等方面。 取代苯甲酰基修饰环糊精对顺式环辛烯(cis-cyclooctene)光异构化反应有非常重要的影响作用,苯环上取代基的性质和取代位置与产物的%ee值和对映体构型之间存在某种内在联系。有目的地选择适宜取代基,设计、合成新型环糊精光增感剂, 有可能按预定目的得到更高%ee值的反式环辛烯;同时,取代苯甲酰基修饰环糊精对cis-cyclooctene光异构化的增感机理有待于进一步阐明。 本论文工作对环糊精的化学修饰以及超分子体系对cis-cyclooctene不对称光异构化反应方面的进展进行了调研。合成了一系列单-6-位取代苯甲酰基修饰环糊精,用于cis-cyclooctene光异构化增感反应,并用圆二色光谱滴定法研究这些环糊精衍生物与cis-cyclooctene的相互作用,以探索光增感反应机理。在此基础上,探讨了环糊精第二面的选择性修饰方法。内容主要包括: 1. 简要介绍了超分子化学的概况,并对环糊精的选择性修饰方法和超分子体系对cis-cyclooctene不对称光异构化反应的主要成果和最新进展进行了评述。 2. 合成了12种单-6-O-(取代苯甲酰基)-β-环糊精,其中10种为新化合物。采用紫外光谱、红外光谱、核磁共振波谱以及质谱等手段对化合物的结构进行了表征。 3. 探索了直接选择性修饰环糊精第二面的便捷新方法。用取代苯甲酰咪唑酯为酰化试剂,0.2M碳酸盐缓冲溶液(pH=9.9)作催化剂,能够有效地活化2-位仲羟基,对环糊精第二面进行选择性修饰,此方法既简便又经济;同时,发现取代苯甲酰基能够在β-CD第二面的2-位、3-位羟基间相互迁移。 4. 用单-6-O-(取代苯甲酰基)-β-环糊精作光增感剂,对cis-cyclooctene光异构化反应进行研究。实验结果证明:取代苯甲酰基上的取代基性质、位置、长度对反应的对映选择性有很大影响;此外,反应体系溶剂极性对产物的%ee值和对映体构型也有重大影响。用单-6-O-(3-甲氧苯甲酰基)-β-CD作增感剂,cis-cyclooctene光异构化反应产物(R)-trans-cyclooctene的对映选择性为45.8%ee,是到目前为止取得的最好对映选择性。 5. 采用圆二色光谱滴定法研究环糊精衍生物与cis-cyclooctene的相互作用,计算包结物的平衡常数,研究包结物的相对稳定性,为探索光增感反应机理提供基础。我们猜测:电子效应对cis-cyclooctene光异构化反应的影响,可能比取代基位置对反应的影响更大,借助电子效应有希望获得更高的%ee值。 Cyclodextrins can be subjected to diverse modifications to give a wide variety of cyclodextrin derivatives, which could not only extend their original molecular binding ability, but also alter their molecular selectivity. Therefore, cyclodextrin chemistry is currently a significant topic in supramolecular chemistry. The more open secondary hydroxyl side of CDs is stated to be catalytically very important, modifications of this face are believed to produce valuable derivatives for catalysis, enzyme mimic, chiral discrimination, etc. Mono-6-O-(substituted benzoyl)-β-CDs as novel supramolecular photosensitizing hosts have recently excited considerable attention in photochirogenesis. The supramolecular photosenstization of cis-cyclooctene mediated by them gave chiral trans-cyclooctene, enantiomeric excess of which was critically affected by the substituent introduced to the sensitizer moiety. In order to enhance the photoenantiodifferentiating ability, and elucidate the origin mechanisms of substituent-dependent enantioselectivity, in this work a series of mono-6-O-(substituted benzoyl)-β-CDs have been synthesized, and applied for enantiodifferentiating photoisomerization of cis-cyclooctene. The major contents are as follows: 1. The general aspects of supramolecular chemistry were descibed briefly. The new progress and important achievements on methods of selective modification of cyclodextrin and supramolecular enantiodifferentiating photoisomerization of cis-cyclooctene were reviewed. 2. Twelve mono-6-O-(substituted benzoyl)-β-CDs including ten novel compounds have been synthesized. Their structures have been characterized by using UV-vis, IR, NMR and MS methods. 3. A new convenient strategy for direct acylation of β-cyclodextrin on the secondary hydroxyl face was achieved by using the combination of N-benzoylimidazole and carbonate buffer in DMF, and the acyl migration between the C-2 and C-3 hydroxyl groups of β-cyclodextrin was found. 4. Experiments using mono-6-O-(substituted benzoyl)-β-CDs as chiral sensitizing hosts for mediating the enantiodifferentiating photoisomerization of cis-cyclooctene, were carried out. The results indicate that enantiomeric excess was critically affected, or even switched in sign, by the substituent introduced to the sensitizer moiety, and polarity of solvent. Using mono-6-O-(3-methoxybenzoyl)-β-CD as chiral sensitizing host, (R)-trans-cyclooctene was obtained in up to 45.8% enantiomeric excess, which is the highest value ever reported for supramolecular photochirogenesis with analogous hosts. 5. The conformational variation of these modified CDs and their complexation behaviors with cis-cyclooctene were examined by circular dichroism spectroscopy in water-methanol mixed solvents, which reveal that the orientation of chromophore was highly sensitive to the type, position and length of the introduced substituents. In the end, the complex stability constants(Ks) were calculated, and the mechanisms of reaction were discussed. Maybe, electronic effects are more important than positions of substituents for mediating the enantiodifferentiating photoisomerization of cis-cyclooctene.

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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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猪场废水COD浓度高、氨氮浓度高、悬浮物浓度高,已成为农村面源污染的主要来源,并严重威胁到农村饮用水安全。猪场废水氨氮浓度高、处理难度大,如何采用经济高效的方法,去除氨氮使其达到排放标准,一直是猪场废水处理中面临的重要难题。 厌氧氨氧化是近年受到国内外水处理研究者广泛关注的新型生物脱氮技术,具有不需要外加有机碳源、节省供氧量、降低能耗等优点。虽然国内外研究者对厌氧氨氧化过程的脱氮机理、厌氧氨氧化菌的生理生化特性等进行了多方面的研究,但已有的报道大多以模拟废水为研究对象,以猪场废水为研究对象的报道,在国内外文献中极少有报导。 本论文以猪场废水为主要研究对象,考察了猪场废水的亚硝化过程、厌氧氨氧化的启动过程,并对亚硝化和厌氧氨氧化联合用于猪场废水脱氮进行了探索。 1.论文首先研究了猪场废水的亚硝化过程,考察了废水水质和主要运行条件对亚硝化过程的影响。实验表明:(1)亚硝化阶段反应时间为8到10h时,出水中氨氮和亚硝酸盐浓度比可达到1:1~1:1.23,满足厌氧氨氧化反应对二者比例的要求;达到前述要求时,氨氮去除率达到58.3~65.6 %,亚硝化率在整个过程均保持在97 %以上,COD去除率在59.2~68.6 %;(2)曝气量(溶解氧)对亚硝化过程影响显著,随着曝气量增大,达到厌氧氨氧化要求的氨氮与亚硝酸盐氮浓度比例所需水力停留时间τ越短,pH出现明显下降的时间越短;(3)τ对应的pH在7.8~8.1之间,无需进行pH调节即可满足厌氧氨氧化反应对pH的要求;(4)氨氮和COD降解过程遵循一级反应动力学,氨氮和COD降解的速率常数分别为0.0656~0.0724 1/h和0.0491~0.0664 1/h。 2.在进行亚硝化过程研究的同时,以模拟废水为试验对象,进行厌氧氨氧化启动研究。以反硝化污泥和养殖厂储水池厌氧底泥的混合污泥作为接种污泥,历时大约100天,培育出具有厌氧氨氧化活性的污泥,氨氮和亚硝酸盐氮最高进水浓度分别为223.8 mg/L和171.4 mg/L,去除率最高分别达48%和41.5%,此时二者消耗比例为1.33:1。 3.在猪场废水的亚硝化研究完成和厌氧氨氧化过程初步启动成功后,在模拟废水中逐步加入猪场废水的亚硝化处理出水,逐步实现亚硝化和厌氧氨氧化的组合。亚硝化出水添加到厌氧反应器后,厌氧氨氧化反应仍可继续进行,且去除效率逐步提高。研究发现添加的亚硝化出水中携带的亚硝化细菌在厌氧氨氧化菌膜外层生长并累积,增加了厌氧氨氧化反应基质的传质阻力,妨碍了厌氧氨氧化效率的提高。 4.亚硝化-厌氧氨氧化实际工程应用探索中,生物接触氧化池可在有效去除废水中的有机物的同时实现亚硝化,出水中氨氮和亚硝酸盐比例平均为1.10,可满足后续厌氧氨氧化的要求;在适宜的进水浓度和温度下,ABR池出现了厌氧氨氧化启动的迹象;研究同时发现,水质的波动和气温的变化是工程中影响厌氧氨氧化菌活性的重要因素。 论文的主要创新点在于:(1)以猪场废水为研究对象,以实现厌氧氨氧化为目标,对亚硝化过程进行了比较详细的考察,获得了亚硝化出水满足厌氧氨氧化要求的工艺条件,通过对其COD和氨氮降解过程的考察,得出亚硝化阶段COD降解和氨氮去除的动力学模型;(2)对亚硝化-厌氧氨氧化处理猪场废水进行了探索,确立了影响其污染物去除率稳定的重要因素。 论文的上述研究成果,为厌氧氨氧化技术的实用性研究提供理论依据。 Piggery wastewater, which is characterized by high concentration of COD、ammonium and suspend substance, has become a most important source of non-point source pollution and also severely threats drinking water security in rural area. How to discharge piggery wastewater with the ammonium concentration meeting standard by economical and effective method? This is the most urgent problem in piggery wastewater treatment. As a new biological nitrogen removal technology, Anammox process has been paid more and more attention by researchers all over the world. Anammox has advantages of no need of organic carbon addition, low oxygen consumption and energy consumption. Plenty of investigations have been carried out to the mechanism, physiological and biochemical characteristic of bacteria about Anammox. Most of researches focused on synthetic wastewater, there is rare report about its application in piggery wastewater. In this paper,experimental studies were performed to investigate Sharon process in treatment of piggery wastewater,the start up process of Annammox using synthetic wastewater were studied, the feasibility of applying Sharon-Anammox process in the nitrogen removal of piggery wastewater was evaluated. 1. Sharon process of piggery wastewater was firstly investigated to analyze the effects of water quality and main running parameters, which meet the NH4+-N to NO2--N ratio requirement of successive Anammox. Results showed: (1)During Sharon Process,after 8~10 hours’ reaction the NH4+-N to NO2--N ratio in effluent reached 1:1.0~1:1.23, when the removal percentage of NH4+-N was 58.3~65.6 %, a semi-nitration rate of above 97 % was achieved during the process; meanwhile 59.2~68.6 % of the COD was also removed. (2)The aeration rate(oxygen) had obvious effect on the hydraulic retention time(τ) which met the NH4+-N to NO2--N ratio requirement of Anammox. As aeration rate increased, the hydraulic retention time(τ) was shortened. (3) The pH corresponding to τ was between 7.8 and 8.1, thus it needed no artificial adjustment. (4) The reduction of ammonia and COD followed the first-order reaction kinetics. The velocity constants of ammonia and COD were 0.0656~0.0724 1/h and 0.0491~0.0664 1/h, respectively. 2. The startup of Anammox process using the artificial wastewater was performed simultaneously with Sharon. The aim was to investigate the running parameters of Anammox and make foundation for the combination stage. By using the mixture of denitrifying sludge and anaerobic sludge in tank of the breeding factory, sludge of Anammox activity was cultivated in UASB after 100 days. The removal percentage of NH4+-N and NO2-N were up to 48% and 41.5%, respectively, when the NH4+-N and NO2-N influent concentration were 223.8 mg/L and 171.4 mg/L, respectively, the NH4+-N and NO2-N removal rate was 1.33:1. 3. After investigation of Sharon and startup of Anammox, effluent of Sharon process was added into the synthetic wastewater to combine Sharon and Anammox step by step. It took some time after the addition of Sharon effluent that Anammox reaction continued and the removal rate kept increasing. It indicated that nitrifying bacteria were carried by the Sharon effluent cumulated in the outer layer of Anammox. This enhanced transfer resistance of Anammox reaction and the increasing removal rate was restrained. 4. In the bio-contact oxidation pond of practical project, Sharon process were carried out successfully and organic compounds were removed effectively. An average NO2-N/ NH4+-N rate of 1:1.0 was achieved in the effluent, which met the requirement of successive Anammox. Under condition of suitable influent concentration and temperature, there was evidence that Anammox could start up in ABR. The variety of wastewater and temperature had great affects on Anammox activity in practical engineering. Innovation of this paper: (1) The Sharon process for treating piggery wastewater was discussed in details. Technological parameters that met requirement of Anammox were obtained. The dynamic models of COD and ammonium removal in the process were educed. (2) Sharon-Ananmmox for treatment of piggery wastewater was investigated, and the primary influencing factors was studied. This paper could be a theoretical consult for research of Anammox utility.

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By including the scalar isovector meson delta, we extend the relativistic mean field model and the one-boson exchange model of changing K-meson in the framework of Schaffner's relativistic mean field model. We re-consider the coupling constants for the interactions between the meson and the baryon and the interactions of the K meson with different mesons as well in various parameter sets. Using our model, we discuss the effective masses of K mesons in the hyperon-rich nuclear matter. We find that the density modification of the K meson mass in the strange nuclear matter is smaller than that in the pure nuclear matter. The influence of the scalar isovector meson 6 on the effective mass of kaon is rather evident. But the extent of the influence is different in different parameter sets.

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A phenol-degrading. microorganism, Alcaligenes faecalis, was used to study the substrate interactions during cell growth on phenol and m-cresol dual substrates. Both phenol and m-cresol could be utilized by the bacteria as,the sole carbon and energy sources. When cells grew on the mixture of phenol and m-cresol, strong substrate interactions were observed. m-Cresol inhibited the degradation of phenol, on the other hand, phenol also inhibited the utilization of m-cresol, the overall cell growth rate was the co-action of phenol and m-cresol. In addition, the cell growth and substrate degradation kinetics of phenol, m-cresol as single and mixed substrates for A. faecalis in batch cultures were also investigated over a wide range of initial phenol concentrations (10-1400 mg L-1) and initial m-cresol concentrations (5-200 mg L-1). The single-substrate kinetics was described well using the Haldane-type kinetic models, with model constants of it mu(m1) = 0.15 h(-1), K-S1 = 2.22 mg L-1 and K-i1 = 245.37 mg L-1 for cell growth on phenol and mu(m2) = 0.0782 h(-1), K-S2 = 1.30 mg L-1 and K-i2 = 71.77 mgL(-1), K-i2' = 5480 (mg L-1)(2) for cell growth on m-cresol. Proposed cell growth kinetic model was used to characterize the substrates interactions in the dual substrates system, the obtained parameters representing interactions between phenol and m-cresol were, K = 1.8 x 10(-6), M = 5.5 x 10(-5), Q = 6.7 x 10(-4). The results received in the experiments demonstrated that these models adequately described the dynamic behaviors of phenol and m-cresol as single and mixed substrates by the strain of A. faecalis.

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The relative partial cross sections for C-13(6+)-Ar collisions at 4.15-11.08 keV/u incident energy are measured. The cross-section ratios sigma(2E)/sigma(SC), sigma(3E)/sigma(SC), sigma(4E)/sigma(SC) and sigma(5E)/sigma(SC) are approximately the constants of 0.51 +/- 0.05, 0.20 +/- 0.03, 0.06 +/- 0.03 and 0.02 +/- 0.01 in this region. The significance of the multi-electron process in highly charged ions (HCIs) with argon collisions is demonstrated (sigma(ME)/sigma(SC) as high as 0.79 +/- 0.06). In multi-electron processes, it is shown that transfer ionization is dominant while pure electron capture is weak and negligible. For all reaction channels, the cross-sections are independent of the incident energy in the present energy region, which is in agreement with the static characteristic of classic models, i.e. the molecular Coulomb over-the-barrier model (MCBM), the extended classical over-the-barrier (ECBM) and the semiempirical scaling laws (SL). The result is compared with these classical models and with our previous work of C-13(6+)-Ne collisions

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The cross-section ratios of double-, triple-, quadruple-, and the total multi-electron processes to the single electron capture process sigma(DE)/sigma(SC), sigma(TE)/sigma(SC), sigma(QE)/sigma(SC) and sigma(ME)/sigma(SC)) as well as the relative ratios among reaction channels in double-electron active, triple-electron active and quadruple- electron active are measured in C-13(6+) -Ne collision in the energy region of 4.15-11.08 keV/u by employing position-sensitive and time-of-flight coincident techniques. It is determined that the cross-section ratios sigma(DE)/sigma(SC), sigma(TE)/sigma(SC), sigma(QE)/sigma(SC) and sigma(ME)/sigma(SC) are approximately the constants of 0.20 +/- 0.03, 0.16 +/- 0.04, 0.06 +/- 0.02 and 0.42 +/- 0.05. These values are obviously smaller than the predictions of the molecular Coulomb over-the-barrier model (MCBM) [J. Phys. B 23 (1990) 4293], the extended classical over-the-barrier model (ECBM) [J. Phys. B 19 (1986) 2925] and the semiempirical scaling laws (SL) [Phys. Rev. A 54 (1996) 4127]. However, the relative ratios among partial processes of DE, TE and QE are found to depend on collision energy, which suggests that the collision dynamics depends on the collision velocity. The limitation of velocity-independent character of ECBM, MCBM and SL is undoubtedly shown.

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The light-front quark model has been applied to calculate the transition matrix elements of heavy hadron decays. However, it is noted that using the traditional wave functions of the light-front quark model given in the literature, the theoretically determined decay constants of the Gamma(nS) obviously contradict the data. This implies that the wave functions must be modified. Keeping the orthogonality among the nS states and fitting their decay constants, we obtain a series of the wave functions for Gamma(nS). Based on these wave functions and by analogy with the hydrogen atom, we suggest a modified analytical form for the Gamma(nS) wave functions. Using the modified wave functions, the obtained decay constants are close to the experimental data. Then we calculate the rates of radiative decays of Gamma(nS) -> eta(b) + gamma. Our predictions are consistent with the experimental data on decays Gamma(3S) -> eta(b) + gamma within the theoretical and experimental errors.