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21.
Effective organizations need capabilities relevant to their missions and must manage those capabilities efficiently. We anticipate capability is more important in industries in which labor is highly paid, while efficiency is more important in industries in which labor is inexpensive. We explore the contributions of capability and efficiency to effectiveness for Major League Baseball teams from 1901 through 2002. Our analysis measures team capability using offensive and defensive statistics and uses Network Data Envelopment Analysis to derive efficiency scores to capture managerial performance. We define effectiveness as the team’s winning percentage. Both capability and efficiency are significant contributors to regular season effectiveness. Capability is more important. Finally, we examine the post-season performance of post-season teams between 1903 and 2002. Our analysis measures post-season performance based on the team’s winning percentage and that of its opponent. Post-season performance is unrelated to capability and managerial performance, accounting for about 1% of post-season success.  相似文献   
22.
 In the literature and in daily work there exist many different models to describe detection limits and quantitation limits in the chemical measurement process (CMP). It is still an open question whether the evaluation of detection and quantitation limits should be an one-off process carried out during the validation of a CMP, or whether it should be a continuous process. Because of these reasons many laboratories have difficulties to interprete such values. It is necessary that the official standardization bodies should do some efforts in the international harmonization of the special standards concerning detection and quantitation limits. Received: 3 November 1997 · Accepted: 25 January 1998  相似文献   
23.
All-solid-state batteries (ASSBs) with inorganic solid electrolytes (SEs) have attracted significant interest as next-generation energy storage. Halides such as Li3YCl6 are promising candidates for SE because they combine high oxidation stability and deformability. However, the ionic conductivities of halide SEs are not as high as those of other SEs, especially sulfides. Here, we discover new lithium-metal-oxy-halide materials, LiMOCl4 (M=Nb, Ta). They exhibit extremely high ionic conductivities of 10.4 mS cm−1 for M=Nb and 12.4 mS cm−1 for M=Ta, respectively, even in cold-pressed powder forms at room temperature, which are comparable to or surpass those of organic liquid electrolytes used in lithium-ion batteries. Bulk-type ASSB cells using the oxyhalides as the cathode SE demonstrate an outstanding rate capability with a capacity retention of 80 % at 5 C/0.1 C. We believe that the proposed oxyhalides are promising SE candidates for the practical applications of ASSBs.  相似文献   
24.
杨卫华 《光谱实验室》2006,23(2):331-333
为了解K2FeO4扣式电池的放电性能和电解液含量对其放电性能的影响,本文自制并采用恒流放电手段测试了含有不同含量饱和KOH电解液的K2FeO4扣式电池的放电性能.恒流放电结果显示,K2FeO4扣式电池中饱和KOH电解液的含量越多,其放电容量越高.  相似文献   
25.
Due to the possibility of making analytical determinations in the presence of non-modelled interferents and to identify the analyte of interest, calibrations based on scores of PARAFAC decomposition of three-way data are becoming increasingly important in routine analysis.Furthermore, the IUPAC and EU (European Decision 2002/657/EC) have accepted the definition given by the ISO 11843 for the capability of detection as the minimum net quantity detectable with a pre-set probability of false positive and false negative. What is more, recently our research group has generalised this definition of capability of detection, CCβ, to multivariate calibrations. In practice, CCβ is a good measure of the quality of the calibration because in its definition it brings together analytical sensitivity with precision in analytical determinations.This paper studies the effect of the pre-treatment of the sample, the signal/noise ratio and the second-order advantage on CCβ when using second-order signals modelled by PARAFAC. All of them are experimental factors which influence the quality of the calibration. Analytical pre-treatment is habitual in the analysis of real samples. Specifically, we analyse the effect of the extraction phase and the clean-up of milk samples on the determination of chlortetracycline by HPLC-DAD. It is shown that it is more efficient to do the joint PARAFAC decomposition of the pure standards with the milk samples.Secondly, the effect of asymmetry on CCβ, according to the path of the noise of the signals, is studied. Specifically, in the determination of naphthalene by excitation-emission spectroscopy, EEM, it is the emission spectrum which limits the capability of detection. It is shown that by eliminating the spectra with the poorest signal/noise ratio in this path, the capability of detection can be substantially improved.Thirdly, the impact on CCβ when the second-order advantage is used, that is when PARAFAC calibration is used over samples with an unknown interference not modelled in the calibration step. This is important to apply a PARAFAC calibration to routine analysis in the IUPAC and European Decision framework. Specifically, in the determination of enrofloxacine in poultry feeding water through excitation-emission fluorescence CCβ is evaluated when the PARAFAC is built only with calibration samples or with the calibration samples plus the test samples with uncalibrated and unknown interferent.  相似文献   
26.
A set of laboratory practices is proposed in which evaluation of the quality of the analytical measurements is incorporated explicitly by applying systematically suitable methodology for extracting the useful information contained in chemical data. Non-parametric and robust techniques useful for detecting outliers have been used to evaluate different figures of merit in the validation and optimization of analytical methods. In particular, they are used for determination of the capability of detection according to ISO 11843 and IUPAC and for determination of linear range, for assessment of the response surface fitted using an experimental design to optimize an instrumental technique, and for analysis of a proficiency test carried out by different groups of students. The tools used are robust regression, least median of squares (LMS) regression, and some robust estimators as median absolute deviation (m.a.d.) or Huber estimator, which are very useful as an alternatives to the usual centralization and dispersion estimators.  相似文献   
27.
《Analytica chimica acta》2004,515(1):55-63
Clenbuterol has been extracted by mixed solid-phase extraction from two biological matrices (bovine hair and urine) and detected by GC/MS (selected ion monitoring (SIM) and full-SCAN modes). The analytical signal has been modelled with univariate and three-way models, namely DTLD, PARAFAC, PARAFAC2, Tucker3 and trilinear PLS. Since clenbuterol is a banned substance a comparative study of the capability of detection (CCβ, X0=0) has been performed as a function of the sample (hair, 74 μg kg−1 and urine, 0.36 μg l−1), the mode in which the signals are monitored (SCAN, 283 μg kg−1 and SIM, 74 μg kg−1) and the statistical model (univariate, 283 μg kg−1 and trilinear PLS, 20.91 μg kg−1). The capability of detection has been calculated as stated in ISO 11843 and Decision 2002/657/EC setting in all cases the probabilities of false positive and of false negative at 0.05.The identification of the mass spectra must be done to confirm the presence of clenbuterol and has been carried out through PARAFAC. The correlation coefficient between the spectra estimated by PARAFAC and the library spectra is 0.96 (hair, SCAN mode) and 1.00 (hair and urine, SIM mode).The Decision 2002/657/EC advocates the use of independent mass fragments to identify banned compounds. These recommendations together with the effect of the number of ions registered on the capability of detection have lead us to select five uncorrelated fragments (86, 243, 262, 264 and 277) from the data set of 210 ions by hierarchical clustering of variables.  相似文献   
28.
Herein, a chemical pre-potassiation strategy via simultaneously treating both glucose derived carbon (GDC) anode and commercial activated carbon (CAC) cathode in potassium-naphthalene-tetrahydrofuran solution is developed for potassium ion hybrid capacitor (PIHC). Combined with in situ and ex situ characterizations, a radical reaction between pre-potassiation reagent and carbon electrodes is confirmed, which not only deactivates electrochemical irreversible sites, but also promotes to pre-form a uniform and dense KF-rich electrolyte film on the electrodes. As a result, the pre-potassiation treatment presents multiple advantages: (I) the initial Coulombic efficiency (CE) of the GDC anode increases from 45.4 % to 84.0 % with higher rate capability; (II) the CAC cathode exhibits the improved cycling CEs and stability due to the enhanced resistance to electrolyte oxidation at 4.2 V; (III) the assembled PIHC achieves a high energy density of 172.5 Wh kg−1 with cycling life over 10000 cycles.  相似文献   
29.
Heterogeneous catalysts are highly advantageous for industrial applications owing to their distinctive merits including easy separation and effective recovery. However, utilizing heterogeneous photocatalysts to harness longer wavelength light remains a critical area of research. This contribution explores the use of edge-functionalized metal-free polyphthalocyanine networks (PPc-x) to promote efficient polymer synthesis under near infrared (NIR) light irradiation. Our screening process revealed that both phenyl-edged PPc-x (PPc-p) and naphthyl-edged PPc-x (PPc-n) offer promising performance for photopolymerization. With the assistance of ppm-level PPc-n catalyst, well-defined polymers were synthesized within a few hours under the regulation of three NIR lights, regardless of shielded by synthetic and biological barriers. An excellent control over the molecular weight and molecular weight distribution was achieved. Furthermore, PPc-x can be easily recovered and reused for multiple cycles, with negligible leaching and maintenance of the catalytic performance. This study expands a new avenue in developing versatile photocatalysts for the modern synthetic toolkits and offer benefits in diverse applications.  相似文献   
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