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851.
852.
The claviform BaFe12O19 crystals were synthesized by the precipitation-toptactic reaction method using α-FeOOH and γ-FeOOH as raw materials respectively. The synthesis processes of BaFe12O19, studied by XRD, SEM, EDS, FT-IR, and TG-DTA techniques, included preparations of precursor γ and precursor α, formations of α-Fe2O3 and BaFe2O4, and production of rod-like BaFe12O19 through dehydroxylation of pod-like FeOOH, followed by reactions of α-Fe2O3 with BaCO3 and BaFe2O4. The crystallinity of α-Fe2O3 and BaCO3 from precursor α was better than from precursor γ due to the direct dehydroxylation of α-FeOOH, resulting in a lower nucleation rate and better crystallinity of BaFe2O4. BaFe12O19 prepared from precursor α showed lower crystallinity and purity with a higher length-diameter ratio than from precursor γ. The VSM results proved that the appearance of final products had an important influence on magnetic properties. 相似文献
853.
Radon-Nikodym theorem in signed Loeb space 总被引:1,自引:0,他引:1
MA Chunhui LI Shenggang SHI Yanwei . College of Mathematics Information Science Shaanxi Normal University Xi’an Shaanxi China . School of Science Xi’an Architecture Technology University Xi’an . Department of Basic Courses Xi’an Peihua University Xi’an 《武汉大学学报:自然科学英文版》2010,15(1):21-24
This paper gives the Radon-Nikodym theorem in signed Loeb space under 1-saturated nonstandard model. First,the nonstandard characterization of absolute continuity is discussed,on which Radon-Nikodym theorem in signed Loeb space is obtained. Then,some facts about a finite signed Loeb measure and its variation are shown. 相似文献
854.
Birds of a Feather Protest Together: Theorizing Self-Organizing Political Protests with Flock Theory 总被引:1,自引:0,他引:1
The current research theorizes decentralized and self-organized political protests via flock theory (Rosen 2002), a theory of emergent self-organization in communicative human interaction. Flock theory draws from a theoretical basis
of emergence and self-organizing systems, and is presented as a theory of decentralized communication structures. Focusing
on the optimization of decentralized networks and roadmap based coordination of organizationally homopholous foci; the current
theory poses a model of human interaction that captures the potentially egalitarian effects of cooperative evolution and collective
action. Case studies of two separate decentralized political protests against Korean government and FARC are offered as evidences
of such phenomena. 相似文献
855.
In order to improve removal for nitrogen in a pilot-scale submerged membrane bioreactor (SMBR), intermittent aeration was
conducted, and the effect on the treatment performance under four kinds of operation condition (run 1, continuous aeration;
run 2, 60/60 min aeration on/off time; run 3, 60/90 min aeration on/off time; run 4, 60/75 min aeration on/off time) was evaluated.
The results showed that depending on the specific on/off of the aeration time ratio, removal efficiency of nitrogen could
be improved significantly, and the removal rates of total nitrogen (TN) under different operation conditions were 28.0%, 59.5%,
66.8% and 70.7%, respectively. There were no obvious differences for removal rates for CODCr and ammonia among different operation conditions. In general, intermittent aeration could be used as a feasible way to improve
treatment performance for nitrogen in the SMBR. 相似文献
856.
Viability criteria for differential inclusions 总被引:2,自引:0,他引:2
Yan Gao 《系统科学与复杂性》2011,24(5):825-834
A method of verifying the viability criterion at a given point for a region with nonsmooth boundary, which is expressed by
a quasidifferentiabl function, under a differential inclusion which is a convex hull of finitely many functions, is proposed.
By this method, determining the viability is transformed into solving a number of systems of linear inequalities, or equivalently
solving a number of linear programming problems. For the other differential inclusion, called the generalized convex process,
it is shown that viability condition holds for a polytope if and only if it holds at all of its vertices. This result is an
extension of corresponding one for a linear control system. 相似文献
857.
858.
The state transfer under control fields is analyzed based on the Bloch sphere representation of a single qubit. In order to
achieve the target from an arbitrary initial state to a target state, the conditions that parameters should satisfy are deduced
separately in two different requirements: One is in the case of the rotation angle around the x-axis being fixed and another is in the situation with a given evolution time. Several typical states trajectories are demonstrated
by numerical simulations on the Bloch sphere. The relations between parameters and the trajectories are analyzed. 相似文献
859.
公路填方路基质量往往难以控制,造成路基沉陷,路面出现反射裂缝等病害,其原因是多方面的,结合多年的施工经验介绍了路基土方填筑施工的质量控制要点,从填方路基到挖方路基的一般规定、施工中的排水、取土坑和护坡道,机械工作要点作了较全面的论述。 相似文献
860.
A rapid process of hybridisation of man and technology, organisation and technology and society and technology is currently
sweeping the world. This process requires a way of (scientific) thinking that takes hybrid systems as the starting point.
Such an approach makes it increasingly important for hybrid systems to be interlinked, enabling them to exchange and share
information through these links. This linking of (hybrid) systems to enable them to exchange and share information can also
be denoted as the realisation of interoperability between (hybrid) systems. Five principles from Luhmann’s systems theory
can help us understand interoperability. Interoperability enables (hybrid) systems to join random coalitions and networks.
The network centric warfare concept is currently the basis for international efforts aimed at the development and application
of interoperability that would enable armed forces to act effectively and efficiently. This paper demonstrates what we can
learn from Luhmann’s system’s theory. 相似文献