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31.
32.
Jamilson R. Campos 《Linear and Multilinear Algebra》2013,61(3):322-346
Considering the successful theory of multiple summing multilinear operators as a prototype, we introduce the classes of multiple Cohen strongly p-summing multilinear operators and polynomials. The adequacy of these classes under the viewpoint of the theory of multilinear and polynomial ideals and holomorphy types is discussed in detail. 相似文献
33.
凌啼 《电信工程技术与标准化》2012,25(6):78-81
全业务运营环境下,为提升运营商竞争力,某移动公司推出无线座机业务,其业务资费比普通的号码套餐较为优惠.本文提出了一种无线座机锁小区的技术方案及系统,该方案及系统能主动适应复杂多变的无线环境和不断调整优化的无线系统,从而有效限制住无线座机终端的优惠范围. 相似文献
34.
芶清泉 《原子与分子物理学报》2011,28(5):785-788
我在一篇论文中提出了一个冷聚变的全原子论,阐明氘原子进入钯晶体间隙位置时扩展成为一个封闭的球形全原子,其价电子完全在球内,围绕氘核运动使氘核对邻近氘核的排斥作用被屏蔽掉,使氘核易于接近而产生聚变。对离子晶体两个负氘离子相互作用是怎样引起聚变的没做详细讨论,本文将对此问题进一步进行详细讨论。 相似文献
35.
We formulate a sufficient condition for the existence of a consistent price system (CPS), which is weaker than the conditional full support condition (CFS). We use the new condition to show the existence of CPSs for certain processes that fail to have the CFS property. In particular this condition gives sufficient conditions, under which a continuous function of a process with CFS admits a CPS, while the CFS property might be lost. 相似文献
36.
E. Almasi N. Kirshen H. Kern 《International journal of environmental analytical chemistry》2013,93(1-4):39-48
Abstract Trace level Volatile Organic Compounds (VOCs) in ambient air are normally determined according to EPA Method TO-14. This method describes the analysis in ambient air of 41 VOCs, ranging in boiling point from -29 to 215°C. It covers a concentration range from 0.2 to 20 parts per billion, volume/volume (ppb), and specifies sample enrichment of a 400 mL air sample on glass beads at -160°C. While this sample volume provides sub-ppb levels of VOC detection for target analytes when using a quadrupole mass spectrometer detector in SIM mode or when using GC detectors, the identification of non-target analytes may only be done in full scan mode for higher concentrations. Also with this sample volume a Nafion dryer is needed for water removal thereby lowering the recovery of polar VOCs. Because of the very high sensitivity of the ion trap MS, relatively small air volumes (60 mL) are adequate to obtain the required or lower detection levels. An integrated air analysis system based on a GC-ion-trap MS has been investigated and is described. This system has a built-in cryogenic trap and necessary valving, internal standard gas sampling loop, and is controlled from the GC-MS workstation. The linearity, precision, and method detection levels obtainable with this system when using small volumes are reported. In addition, examples of the quantitative and qualitative analysis of ambient air samples are shown. 相似文献
37.
Dr. Yao-Yao Wang Dr. Hong-Hong Fan Zhi-Wei Wang Wan-Yue Diao Dr. Chao-Ying Fan Prof. Xing-Long Wu Prof. Jing-Ping Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(66):15173-15181
Owing to low ion/electron conductivity and large volume change, transitional metal dichalcogenides (TMDs) suffer from inferior cycle stability and rate capability when used as the anode of lithium-ion batteries (LIBs). To overcome these disadvantages, amorphous molybdenum sulfide (MoSx) nanospheres were prepared and coated with an ultrathin carbon layer through a simple one-pot reaction. Combining X-ray photoelectron spectroscopy (XPS) with theoretical calculations, MoSx was confirmed as having a special chain molecular structure with two forms of S bonding (S2− and S22−), the optimal adsorption sites of Li+ were located at S22−. As a result, the MoSx electrode exhibits superior cycle and rate capacities compared with crystalline 2H-MoS2 (e.g., delivering a high capacity of 612.4 mAh g−1 after 500 cycles at 1 A g−1). This is mainly attributed to more exposed active S22− sites for Li storage, more Li+ transfer pathways for improved ion conductivity, and suppressed electrode structure pulverization of MoSx derived from the inherent chain-like molecular structure. Quantitative charge storage analysis further demonstrates the improved pseudocapacitive contribution of amorphous MoSx induced by fast reaction kinetics. Moreover, the morphology contrast after cycling demonstrates the dispersion of active materials is more uniform for MoSx than 2H-MoS2, suggesting the MoSx can well accommodate the volume stress of the electrode during discharging. Through regulating the molecular structure, this work provides an effective targeted strategy to overcome the intrinsic issues of TMDs for high-performance LIBs. 相似文献
38.
森林火灾“爆燃”现象的特征是突然发生的高强度、高蔓延速度的燃烧。目前为止,关于“爆燃火”的原因还没有达成共识。以无人机视角下对林木爆燃火特性研究,以四川木里特大森林火灾为研究对象,通过分析凉山州某森林扑火部队3月31日木里森林火灾当天KWT(科卫泰)无人机航拍火场画面,结合无人机实时影像及实地调研数据,分析了峡谷地形林火蔓延时空特征,探讨了峡谷中风向风速变化时空分布规律,研究了地形变化条件下,不同海拔高度风速特征,建立了无人机倾角测量风速模型(其中为风速m·s-1,为无人机倾角°)。结果表明,高山峻岭特殊地形环境下每天4:00—12:00时间段为静风期,为峡谷林火扑救最佳时期;午后15:00—17:00和晚上20:00—22:00为山谷地形风速活跃期;仿真软件数据显示山顶、谷底与山腰不同海拔位置的风速风向不统一,谷底会产生乱流现象,且风速与海拔不存在正相关关系,小气候在复杂地形中占主导影响地位;在谷口至山谷深处的中间位置会出现气流速度的波峰状态,并易形成乱流,为爆燃火发生提供了客观必要条件。该研究可为复杂地形环境下,森林草原火灾扑救安全提供数据和技术支撑。 相似文献
39.
The performance of active queue management (AQM) is measured in terms of throughput, delay, queue size, and loss rate. We have carried out the optimized performance measure of throughput for AQM scheme random early detection (RED) using full factorial design (FDD) technique that is a new approach of performance analysis particularly for congestion control algorithms. We have considered the input factors, viz, buffer size, maximum threshold, and the number of file transfer protocol (FTP) sources for the evaluation of RED that can be used for other AQM schemes, viz, adaptive RED, three‐section RED (TRED), and adaptive queue management with random dropping (AQMRD). The effect of each input factor as well as their interactions are evaluated using factorial design technique that results to obtain the nonlinear equation for performance measure in terms of input factors buffer size, maximum threshold, and the number of FTP sources. Finally, we show the contour plots for variation of performance measure throughput (steady state) from minimum to maximum values with respect to the different setting of input parameters. 相似文献
40.
Saurabh B. Ganorkar Suraj R. Chaudhari Preeti S. Bobade Sagar H. Pawar Atul A. Shirkhedkar 《Biomedical chromatography : BMC》2022,36(5):e5345
Rufinamide is used presently to treat Lenaux–Gastaut syndrome. A full factorial design and desirability approach was investigated for the optimization of hydrolytic stress via response surface curves (RSCs). The degradation impurities were identified and resolved using reversed-phase high-performance liquid chromatography (RP-HPLC) on the Qualisil® BDS C8 column. Acetonitrile–water (29:71, v/v) was optimized for the mobile phase and used at a flow rate of 1.0 ml/min with detection at a wavelength of 230 nm. Rufinamide showed appreciable susceptibility to hydrolysis under acidic and alkaline stress, and substantial degradation in the neutral condition. It degraded much less under oxidative stress. Exposure towards thermal and photolytic stress conditions indicated appreciable stability. The developed method was subjected to validation as per the recommendations of the International Conference on Harmonization. The proposed method showed no influence from the excipients and the degradation products. As well as good precision and accuracy in determination, the method showed a linear response between 2 and 12 μg ml−1. The method was extended for determination in a human plasma sample, which resulted in excellent recovery without interference from matrix effects. The combined use of desirability and design for the optimization of acidic and alkaline hydrolytic stress led to simple and rapid analysis. 相似文献