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61.
The rates of oxidation of Fe(II) by H(2)O(2) in the presence of sodium perchlorate, sodium nitrate, sodium chloride and sodium sulfate salts (0-1M) have been compared in the study. Experiments were carried out in a batch reactor, in the dark, at pH <3, 25+/-0.5 degrees C and at controlled ionic strength (< or =1M). The experimental results showed that the rates of oxidation of Fe(II) in the presence of chloride, nitrate and perchlorate were identical. In the presence of sulfate, the rate of oxidation of Fe(II) was faster and depended on the pH and the concentration of sulfate. The pseudo second-order rate constants for the reaction of H(2)O(2) with Fe(2+), FeCl(+) and FeSO(4) were determined as 55+/-1, 55+/-1 and 78+/-3 M(-1) s(-1), respectively. 相似文献
62.
LAN emulation on an ATM network 总被引:1,自引:0,他引:1
Hong Linh Truong Ellington W.W. Jr. Le Boudec J.Y. Meier A.X. Pace J.W. 《Communications Magazine, IEEE》1995,33(5):70-85
The authors evaluate architecture alternatives relating to the provision of a LAN emulation service over a connection-oriented ATM network, and present the LAN emulation architecture as actually adopted by the ATM Forum LANE SWG. The role of servers is discussed as is the provision of broadcast/multicast services 相似文献
63.
基于激光扫描技术的三维模型重建 总被引:4,自引:1,他引:4
通过分析三维激光扫描系统获取的点云数据,得到了利用点云数据构建三维模型的技术、方法和流程。介绍了利用地面三维激光扫描仪获取点云数据的过程以及结合RiSCAN PRO软件和Geomagic Studio软件进行建模的方法。对原始测量的点云数据进行处理(去除噪声,平滑,对多站点数据做拼接配准,提取目标建筑物等)得到正确和完整的目标建筑物的表面信息,然后构建三角网建立它的三维表面模型,最后通过所拍的照片进行纹理映射得到真实的三维模型。实验结果表明,利用上述方法可以有效地处理三维激光扫描获取的点云数据,实现对建筑物快速三维可视化建模。 相似文献
64.
This article considers energy‐efficient power control schemes for interference management in uplink spectrum‐sharing heterogeneous networks that maximize the energy efficiency of users, protect the macro base station, and support users with QoS consideration. In the first scenario, we define the objective function as the weighted sum of the energy efficiencies and develop an efficient global optimization algorithm with global linear and local quadratic rate of convergence to solve the considered problem. To ensure fairness among individual user equipments (UEs) in terms of energy efficiency, we consider the max‐min problem, where the objective is defined as the weighted minimum of the energy efficiencies, and a fractional programming theory and the dual decomposition method are jointly used to solve the problem and investigate an iterative algorithm. As by‐products, we further discuss the global energy efficiency problem and consider near‐optimal schemes. Numerical examples are provided to demonstrate significant improvements of the proposed algorithms over existing interference management schemes. 相似文献
65.
B. Adhikari T. Howes B. R. Bhandari V. Truong 《International Journal of Food Properties》2013,16(3):323-351
Levitation and free‐flight techniques applied to investigate the drying kinetics and morphology of single drops containing dissolved solids and suspensions are reviewed. A review of works related to receding interface model proposed to quantify the drying kinetics of single drops along with techniques to measure the kinetic parameters such as moisture diffusivity, thermal conductivity and specific heat capacity is presented. Problems associated with spray drying of sugar‐rich compounds are briefly discussed and possible links of stickiness and flavor retention with glass transition temperature (Tg), temperature history, drying rate and morphological changes including skin formation, as monitored through single drop experiments, are explored. 相似文献
66.
Iva Blazkova Hoai Viet Nguyen Simona Dostalova Pavel Kopel Maja Stanisavljevic Marketa Vaculovicova Marie Stiborova Tomas Eckschlager Rene Kizek Vojtech Adam 《International journal of molecular sciences》2013,14(7):13391-13402
Magnetic particle mediated transport in combination with nanomaterial based drug carrier has a great potential for targeted cancer therapy. In this study, doxorubicin encapsulation into the apoferritin and its conjugation with magnetic particles was investigated by capillary electrophoresis with laser-induced fluorescence detection (CE-LIF). The quantification of encapsulated doxorubicin was performed by fluorescence spectroscopy and compared to CE-LIF. Moreover, the significant enhancement of the doxorubicin signal was observed by addition of methanol into the sample solution. 相似文献
67.
Abowd G.D. Hayes G.R. Iachello G. Kientz J.A. Patel S.N. Stevens M.M. Truong K.N. 《Pervasive Computing, IEEE》2005,4(4):67-73
Conducting user-centered design is a primary challenge in ubiquitous computing. Two kinds of prototyping techniques can be particularly effective for developing mobile and ubiquitous computing applications: compound prototypes and situated experience prototypes. Compound prototypes combine the final product's user interface (UI) with a computational implementation that runs on a separate system without the resource constraints of the target device. This model lets researchers and designers evaluate a new application's physicality and aesthetics as well as its functionality. Situated experience prototypes, or paratypes, include experimental protocols that attempt to reproduce user interaction with the system in real situations, and can optionally use common prototyping instruments such as paper mock-ups or physical props. Using our Personal Audio Loop (PAL) project as a case study, we discuss how you can fruitfully employ compound prototypes and paratypes when designing and developing mobile and ubiquitous computing applications. 相似文献
68.
While existing work concentrates on developing QoS models of business workflows and Web services, few tools have been developed
to support the monitoring and performance analysis of scientific workflows in Grids. This paper describes novel Grid services
for dynamic instrumentation of Grid-based applications, performance monitoring and analysis of Grid scientific workflows.
We describe a Grid dynamic instrumentation service that provides a widely accessible interface for other services and users
to conduct the dynamic instrumentation of Grid applications during the runtime. We introduce a Grid performance analysis service
for Grid scientific workflows. The analysis service utilizes various types of data including workflow graphs, monitoring data
of resources, execution status of activities, and performance measurements obtained from the dynamic instrumentation of invoked
applications, and provides a rich set of functionalities and features to support the online monitoring and performance analysis
of scientific workflows. Workflows and their relevant information including performance metrics are stored and utilized for
comparing the performance of constructs of different workflows and for supporting multi-workflow analysis.
The work described in this paper is supported in part by the Austrian Science Fund as part of the Aurora Project under contract
SFBF1104 and by the European Union through the IST-2002-511385 project K-WfGrid. 相似文献
69.
70.
NK Leidy 《Canadian Metallurgical Quarterly》1995,27(1):23-34
The extent to which individuals with a chronic physical illness perform their day-to-day activities and maintain the independence and autonomy they desire is both an indicator of adaptation and an important clinical outcome criterion. Yet the concept of functional performance is not well understood. Studies of people with chronic obstructive pulmonary disease (COPD) have attempted to identify physiologic and psychosocial factors that contribute to functioning in this population. These studies have used a melange of terms, including functional status, functional ability, quality of life, and health status interchangeably. They have also employed a variety of instruments to operationalize functional performance and an assortment of predictors to understand the phenomena. Perhaps as a result of this disarray, no attempt has been made to synthesize the literature for nursing research and practice. The purpose of this paper is to summarize the research on functional performance in people with COPD, indicate areas of understanding and quandary, suggest possible flaws, and propose several new directions for practice and research. 相似文献