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11.
12.
Yoshito Mitani Judith Velina Lara-Manzano Aaron Rodriguez-Lopez 《Accreditation and quality assurance》2008,13(7):421-426
According to the experience of the successful implementation of proficiency tests (PT) by using the certified reference value
as the assigned value, a new scheme of evaluation is presented by suggesting the use of the uncertainty associated with the
certified value. The technical performance of laboratories is evaluated by the parameter quadratic mean error (QME), which
is the square root of the sum of the square of the bias and that of the standard deviation of the laboratory. This parameter
is considered as the estimate of the measurement uncertainty of the laboratory and is compared to the uncertainty (U) associated with the certified value provided by an NMI. Considering that the calibration and measurement capability, known
as the CMC, is recognized among NMIs, the ratio QME/U enables us to compare the PT relative to the CMC of an NMI, and, consequently, to any other comparison results based on the
CMC of signatories of the mutual recognition arrangement (MRA) of the International Committee of Weights and Measure (CIPM).
Presented at BERM-11, October 2007, Tsukuba, Japan. 相似文献
13.
14.
Y. Ben-Aryeh 《Foundations of Physics Letters》2006,19(7):747-756
Pseudo-Hermitian Hamiltonians and pseudo-Hermitian coupling between two electromagnetic modes are analyzed by using similarity
transformations of Hermitian Hamiltonians or of Hermitian operators, including a special metric and biorthogonal relations
replacing the usual orthogonal relations used in quantum mechanics. The coupling between two electromagnetic (em) modes including
certain decay and amplification processes is related to a coupling matrix G which has parity-time (PT) symmetry and which obeys the pseudo-Hermiticity condition ηGη−1 = G
† where η is a metric. The linear equations representing the pseudo-Hermitian coupling between the two em modes are diagonalized,
in the interaction picture, by introducing ‘dressed’ αˉ and β~ operators which have real or pure imaginary eigenfrequencies.
The commutation-relations (CR) for the α~ and β~ operators and for the two-mode operators ā and b~, in the interaction picture
and under the condition of real eigenfrequencies are obtained by the use of the pseudo-Hermiticity property of the G matrix. These CR for real eigenfrequencies, are preserved in time without any Langevin noise terms. 相似文献
15.
In this paper, for the first time, an inorganic–organic hybrid material based on ZnO nanoparticles was anchored to a composite made from polythiophene and hexagonally ordered silica (ZnO/PT/SBA-15) for use in solid-phase fibre microextraction (SPME) of medicinal plants. A homemade SPME apparatus was used for the extraction of volatile components of Ziziphora tenuior L. A simplex method was used for optimisation of five different parameters affecting the efficiency of the extraction. The main constituents extracted by ZnO/PT/SBA-15 and PDMS fibres and hydrodistillation (HD) methods, respectively, included pulegone (51.25%, 53.64% and 56.68%), limonene (6.73%, 6.58% and 8.3%), caryophyllene oxide (5.33%, 4.31% and 4.53%) and 1,8-cineole (4.21%, 3.31% and 3.18%). In comparison with the HD method, the proposed technique could equally monitor almost all the components of the sample, in an easier way, in a shorter time and requiring a much lower amount of the sample. 相似文献
16.
Promotion is an essential stage of any product life cycle. All firms either concerned with single or multiple products promote their products. Advertising is the most dominated form of promotion for most of the products. Our research focuses on firms which produces a multiple range of products and advertise them using available media options. The budget constraint forms the major restriction. The existing research in media allocation of multiple products ignores the market segmentation and formulates the media plan assuming all segments alike. In this paper we formulate a media planning problem for allocating the available budget in multiple media that are found suitable for the advertising of multiple products considering marketing segmentation aspect of advertising. The objective is to maximize the total reach in all the segments. Goal programming technique is used to solve the problem. A case study is presented to show the real life application of the model. 相似文献
17.
文章针对铝厂每月的总供电量与总用电量之间存在较大误差的情况 ,结合分公司的电能计量网络分布情况及电网运行现状 ,详细分析了可能引起误差的各种原因 ,以求得相应对策 相似文献
18.
吴学谋 《应用数学和力学(英文版)》1993,(2)
A new type of philosophy and mathematics from the pansystems view is introduced here,including the7 philosophy theories(7PT)and related mathematizing researches.Many second/third philosophies are developed within pansystems framework and related applications to APTMS. 相似文献
19.
该文用标准方法,计算了schrdinger电子与双荷子束缚系统的电偶极矩,证明了此系统违反通常意义下的PT不变性。 相似文献
20.
We report some highly unusual phase behavior, of general implication for condensed matter, on the polymer poly(4-methyl-pentene-1) (P4MP1) induced by changes in pressure and temperature, as observed in situ by x-ray diffraction. Upon increasing pressure beyond a threhold, the polymer, crystalline under ambient conditions, loses its crystalline order isothermally, passing through a continuously varying sequence of mesomorphic states, the process being reversible. This behavior is observed in two widely separated temperature regions, suggesting, for the first time in a single component system, the possibility of reentrant liquid-crystal and amorphous phases. At the upper temperature region (ca. 250°C) there is a consecutive increase and decrease of melting point with pressure. In the lower temperature region (room temperature) the pressure converts the crystal into an amorphous-like glass obviating the need for going through the melt first, and this in a reversible manner. The latter pressure-induced disordered phase converts into crystal on raising the temperature, and reverts to the glassy, disordered phase on lowering the temperature. Some aspects of this behavior have been found quite recently in water-ice and silica but the process of “melting on cooling” has no precedent in any known system. Other unexpected findings include a new pressure-induced modification of P4MP1 with a one-way only entry with temperature, but full reversibility with pressure leading to a triple point in the PT phase diagram. The above highly uncommon results are putting several prevailing preconceptions to test which are being scrutinized. In the course of it some early expectations on general phase behavior, allowing among others for reentrant phases in one component systems, are being invoked as potentially appropriate for certain polymeric systems, if not for condensed matter in general. © 1993 John Wiley & Sons, Inc. 相似文献