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31.
This paper reports on a microfluidic device for the screening of organophosphonate nerve agent degradation products. The miniaturized system relies on an efficient chip-based separation of alkyl methylphosphonic acids (breakdown products of Sarin, Soman, and VX nerve agents) followed by their sensitive contactless conductivity detection. Experimental parameters relevant to the separation and detection processes have been optimized to yield high sensitivity (with 48-86 microg L(-1) detection limits), fast response (50 s for a three alkyl methylphosphonic acid mixture), high precision (RSD = 3.8-5.0%), and good linearity (over the 0.3-100 mg L(-1) range). Applicability to natural (river) water samples is demonstrated. The new microsystem offers promise for monitoring degradation products of chemical warfare agents, with advantages of speed/warning, efficiency, portability, sample size, and cost compared to conventional ion chromatography or capillary electrophoresis systems. 相似文献
32.
The Ferroelectric relaxor ternary system 0.5PZN-(0.5 – x)PFN-xBZN was prepared using the columbite precursor method. The stability of the perovskite phase was studied as a function of BZN content in the system. It was observed that BZN is a good stabilizer of perovskite phase because of the high value of electronegativity difference between its cation and anion. It has also been observed that addition of BZN increases the dielectric maxima peak value and decrease the Curie temperature of the ceramics. The ternary composition 0.5PZN-0.425PFN-0.075BZN has been identified for MLCs applications. It has a T
c of around room temperature with a peak dielectric constant 6400 and tan 0.05. The mechanical properties of relaxor materials have also been studied and reported. 相似文献
33.
34.
This paper presents and studies the Canadian Truck Driver Scheduling Problem (CAN-TDSP), which is the problem of determining whether a sequence of locations can be visited within given time windows in such a way that driving and working activities of truck drivers comply with Canadian Commercial Vehicle Drivers Hours of Service Regulations. Canadian regulations comprise the provisions found in US hours of service regulations as well as additional constraints on the maximum amount of driving and the minimum amount of off-duty time on each day. We present two heuristics and an exact approach for solving the CAN-TDSP. Computational experiments demonstrate the effectiveness of our approaches and indicate that Canadian regulations are significantly more permissive than US hours of service regulations. 相似文献
35.
In this paper we have proposed a dynamic pricing scheme for the contributing peers in the Video on Demand (VoD) system. The
scheme provides an effective mechanism to maximize the profit through the residual resources of the contributing peers. A
utilization function is executed for each contributing peer to estimate the utility factor based on the parameters such as
initial setup cost, holding cost, chaining cost and salvage cost. In this paper, we urge an effective dynamic pricing algorithm
that efficiently utilizes a range of parameters with a varying degree of complexity. The key findings of the algorithm are
(i) each contributing peers are benefitted by the monetary based on its resource contributions to the VoD system and (ii)
a high degree of social optimum is established by proficiently aggregating the contributing peer’s resources with the overall
resources of the VoD system. We validate our claim by simulating the proposed dynamic pricing scheme with other standard pricing
schemes such as altruism, cost model and game theory perspective. The result of our dynamic pricing scheme shows the best
utility factor than other standard pricing schemes. 相似文献
36.
Jajoo Gaurav Kumar Yogesh Kumar Ashok Yadav Sandeep Kumar 《Wireless Personal Communications》2020,115(4):3137-3153
Wireless Personal Communications - Cluster analysis is a commonly used technique by investors to create a diversified portfolio. The approach aims at maximizing returns for a tolerable degree of... 相似文献
37.
Gupta Naveen Singh Akash Deep Shrivastava Parth Bohara Vivek Ashok 《Wireless Personal Communications》2019,109(1):579-593
Wireless Personal Communications - This paper analyzes the performance of two-way OFDMA based cooperative device-to-device communication (C-D2D) framework in a heterogeneous cellular network. In... 相似文献
38.
Shweta Bhat Sheon Mary Reema Banarjee Ashok P. Giri Mahesh J. Kulkarni 《Proteomics. Clinical applications》2014,8(1-2):19-34
Both enzymatic and nonenzymatic PTMs of proteins involve chemical modifications. Some of these modifications are prerequisite for the normal functioning of cell, while other chemical modifications render the proteins as “neo-self” antigens, which are recognized as “non-self” leading to aberrant cellular and humoral immune responses. However, these modifications could be a secondary effect of autoimmune diseases, as in the case of type I diabetes, hyperglycemia leads to protein glycation. The enigma of chemical modifications and immune response is akin to the “chick-and-egg” paradox. Nevertheless, chemical modifications regulate immune response. In some of the well-known autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis, chemically modified proteins act as autoantigens forming immune complexes. In some instances, chemical modifications are also involved in regulating immune response during pathogen infection. Further, the usefulness of proteomic analysis of immune complexes is briefly discussed. 相似文献
39.
Low Cycle Fatigue (LCF) on smooth hour glass specimens and Fatigue Crack Propagation (FCP) studies on Single Edge Notch (SEN) specimens were carried out at room temperature on four Cu-Al polycrystalline alloys to investigate the effects of Stacking Fault Energy (SFE) and mechanical property variations on fatigue characteristics. Significant improvements in fatigue properties were observed for alloys of low SFE. A microhardness technique was used to delineate the fatigue plastic zone ahead of stopped cracks at several stress intensity ranges for all the alloys. Planar slip was associated with a less than a second power dependence of plastic zone size on the stress intensity range. Transmission Electron Microscopy (TEM) was used to observe the substructures that developed both in LCF at different strain ranges and also ahead of fatigue cracks at different stress intensity ranges. Fractography was carried out to study the micromechanisms of crack propagation using a two stage replication technique. The experimental results were in good agreement with a theoretical model for FCP developed previously by the authors which incorporates mechanical and microstructural variables. 相似文献
40.
Goel R.K. 《中国矿业大学学报(英文版)》2014,(6)
A considerable amount of tunnelling has been going on in India for various projects such as hydroelectric power, irrigation, roads and railways. Most of these projects are located in Himalayas, far awa... 相似文献