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81.
混合工业污泥热解及动力学特性实验研究 总被引:1,自引:0,他引:1
工业污泥中一般都含有大量的病原菌、寄生虫、致病微生物,以及砷、铜、铬、汞等重金属和二恶英、放射性元素等难以降解的有毒有害物质,工业污泥处理与处置已成为我国突出的环境问题之一.文中针对三种典型工业污泥(制药、造纸、啤酒的工业污泥)及其不同的质量混合比,采用热重法研究了其单一及混合物的热解及动力学机理与特性,研究了其不同热解温度阶段的动力学参数,并得到不同条件下的热解特征温度和特征指数.研究结果表明,制药、造纸、啤酒工业污泥在低温区、中温区、高温区的热解反应级数分别为1.、2、1. 相似文献
82.
83.
MgCNi3, an intermetallic compound superconductor with a cubic perovskite crystal structure, has been synthesized using fine Mg and Ni powders and carbon nanotubes (CNTs) as starting materials by the conventional powder metallurgy method. The composition, microstructure and superconductivity are characterized using x-ray diffraction (XRD), energy dispersive x-ray (EDX) analysis, scanning electron microscopy (SEM), and superconducting quantum interference device (SQUID) magnetometer. The results indicate that the phases of the synthesized samples are MgCNi3 (major phase) and traces of C and MgO. The MgCNi3 particle sizes range from several hundreds of nanometres to several micrometres. The onset superconducting transition temperature Tc of the MgCNi3 sample is about 7.2 K. The critical current density Jc is about 3.44 × 10^4 A/cm^2 calculated according to the Bean model from the magnetization hysteresis loop of the slab MgCNi3 sample at 5 K and zero applied field. 相似文献
84.
KE Jian-Hong LIN Zhen-Quan CHEN Xiao-Shuang 《理论物理通讯》2006,46(1):161-166
An aggregation-migration-annihilation model is proposed for a two-species-group system. In the system, aggregation reactions occur between any two aggregates of the same species and migration reactions between two different species in the same group and joint annihilation reactions between two species from different groups. The kinetics of the system is then investigated in the framework of the mean-field theory. It is found that the scaling solutions of the aggregate size distributions depend crucially on the ratios of the equivalent aggregation rates of species groups to the annihilation rates. Each species always scales according to a conventional or modified scaling form; moreover, the governing scaling exponents are nonuniversal and dependent on the reaction details for most cases. 相似文献
85.
The thermoelastic properties of CaO over a wide range of pressure and
temperature are studied using density functional theory in the
generalized gradient approximation. The transition pressure taken
from the enthalpy calculations is 66.7GPa for CaO, which accords
with the experimental result very well. The athermal elastic moduli
of the two phases of CaO are calculated as a function of pressure up
to 200GPa. The calculated results are in excellent agreement with
existing experimental data at ambient pressure and compared
favourably with other pseudopotential predictions over the pressure
regime studied. It is also found that the degree of the anisotropy
rapidly decreases with pressure increasing in the B1 phase, whereas
it strongly increases as the pressure increases in the B2 phase. The
thermodynamic properties of the B1 phase of CaO are predicted using
the quasi-harmonic Debye model; the heat capacity and entropy are
consistent with other previous results at zero pressure. 相似文献
86.
研究了一系列钌(Ⅱ)多吡啶配合物对pBR 322DNA的光断裂作用,并与光谱法和粘度法的研究结果进行了对比.实验结果表明,钌(Ⅱ)多吡啶配合物光断裂DNA的能力不仅与配合物与DNA相互作用的结合模式和结合强度有关,还与配合物自身的电子结构有关;钌(Ⅱ)多吡啶配合物对DNA的光断裂存在立体选择性;其断裂机理是激发态的配合物与溶液中的氧分子发生能量转移生成单线态氧活性氧化物种,将鸟嘌呤碱基氧化而导致DNA断裂.本研究对于遗传工程中的化学核酸酶以及以DNA为靶标的药物设计有重要的意义. 相似文献
87.
近年来 ,以钌 ( )多吡啶配合物为探针研究 DNA的结构已成为生物无机化学领域中的一个热点[1,2 ] .这些配合物由于热力学稳定性好 ,光化学和光物理信息丰富 ,在研究 DNA内部的电子转移和Fig.1 Structures of the ligandsDNA的结构识别等方面均有重要的作用[3~ 7] .在配合物与 DNA的相互作用中 ,配合物的形状、大小以及中心离子电荷等都有一定的影响[8] ,其中 ,配合物的形状起着至关重要的作用 ,与 DNA的形状匹配的配合物与DNA的结合较强 .这些配合物中通常含有平面性较大的芳香环配体 ,可插入到 DNA的碱基对之间 ,并与 DNA具有… 相似文献
88.
We study the kinetic behavior of a two-species aggregation-migration model in which an irreversible aggregation
occurs between any two clusters of the same species and a reversible migration occurs simultaneously between two different species. For a simple model with constant aggregation rates and
with the migration rates
KA(i;j)=K'A(i;j) ∝ijv1 and
KB(i;j)=K'B(i;j) ∝ijv2, we find that the evolution behavior of the system depends crucially on the
values of the indexes v1 and v2. The aggregate size
distribution of either species obeys a conventional scaling law for most cases. Moreover, we also generalize the two-species system to the multi-species case and analyze its kinetic behavior
under the symmetrical conditions. 相似文献
89.
GUO Jian-Hong 《理论物理通讯》2004,41(1):37-40
The interaction of $N$ two-level atoms with both a two-mode cavity
field and an external classical pumping field, and with the fields being
degenerate in frequency, is studied in the regime where the atoms
and fields are highly detuned. This dispersive interaction
can be used to generate a large number of important entangled coherent states
conditional on the initial atomic states and state-selective measurements.
A dynamical relation is established between the results for the case with continuous
pumping and the case without external driving where the coherent field is
put in as the initial condition. 相似文献
90.
We have studied the kinetic behaviours of irreversible aggregation-annihilation models with cluster removals. In the models, an irreversible aggregation reaction occurs between any two clusters of the same species and an irreversible annihilation reaction occurs simultaneously between two different species; meanwhile, the clusters of large size are gradually removed from the system. In a mean-field limit, we obtain the general solutions of the cluster-mass distributions for the cases with an arbitrary removal probability. We found that the cluster-mass distribution of either species satisfies a generalized or modified scaling form. The results also indicate that the evolution behaviours of the systems depend strongly on the details of the reaction events. 相似文献