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101.
This text summarises the PhD thesis that Roel Leus presented to obtain the degree of Doctor in Applied Economics at the Katholieke Universiteit Leuven, in September 2003. The promotor of the thesis was professor Willy Herroelen. The thesis is written in English and is available from the authors website. The goal of the thesis was to provide recommendations for the detailed scheduling of multi-project organisations, when a certain degree of uncertainty exists about a number of characteristics of the project. Up till now, the majority of the literature on project scheduling has consisted of deterministic models for planning a single project: both the uncertainty aspect as well as the intrinsic difficulty of coordination of a portfolio of projects have been largely ignored.Received: October 2003, MSC classification:
09B35, 90B36 相似文献
102.
Ilya?KuselmanEmail author Alexander?Weisman Wolfhard?Wegscheider 《Accreditation and quality assurance》2003,8(11):530-531
The current situation in the pharmaceutical industry is discussed, when the traceability of measurement (analytical) results to certified values of pharmacopoeial reference standards is required, without evaluating their uncertainties. It is shown that the evaluation of measurement uncertainty is necessary for understanding the level of confidence of the analytical results and their comparability, particularly during preparation and characterisation of the reference standards.Papers published in this section do not necessarily reflect the opinion of the Editors, the Editorial Board and the Publisher. Apart from exceptional circumstances, they are not submitted to the usual referee procedure and go essentially unaltered. 相似文献
103.
Clifford algebraic geometry corresponds to Minkowski space. Using the discrete structure of Minkowski space, we can abstract
a class n-dimensional hyperbolic Hilbert phase space. To discussing the causality of physical event in Minkowski space, we
can obtain the geometrical interpretation of uncertainty relation. 相似文献
104.
105.
106.
Roland Wittje 《Physics in Perspective (PIP)》2007,9(4):406-433
In the late 1940s and the 1950s, Norwegian nuclear scientists, engineers, and administrators were deeply split over their
nation’s goals, organization, politics, and tools for research in nuclear physics. One faction was determined to build a nuclear
reactor in Norway, while another fiercely opposed the reactor plans and focused on particle accelerators. The first faction
comprised scientific entrepreneurs and research technologists, the second academic scientists, most of whom began their research
careers in nuclear physics in the 1930s. To understand this conflict, I trace the development of nuclear research in Norway
from the early 1930s to the mid-1950s, placing it within an international context.
Roland Wittje is working on his habilitation thesis in the History of Science Unit at the University of Regensburg, Germany. 相似文献
107.
108.
C. S. Unnikrishnan 《Foundations of Physics Letters》2000,13(2):197-200
An experiment proposed earlier by Karl Popper in his critique of the Copenhagen interpretation was realized recently by Kim and Shih. We show that the Copenhagen interpretation is consistent with the results, contrary to Popper's expectation. We examine the role of signal locality and momentum conservation in Popper's experiment and in the realization by Kim and Shih. 相似文献
109.
Sampling errors can be divided into two classes, incorrect sampling and correct sampling errors. Incorrect sampling errors arise from incorrectly designed sampling equipment or procedures. Correct sampling errors are due to the heterogeneity of the material in sampling targets. Excluding the incorrect sampling errors, which can all be eliminated in practice although informed and diligent work is often needed, five factors dominate sampling variance: two factors related to material heterogeneity (analyte concentration; distributional heterogeneity) and three factors related to the sampling process itself (sample type, sample size, sampling modus). Due to highly significant interactions, a comprehensive appreciation of their combined effects is far from trivial and has in fact never been illustrated in detail. Heterogeneous materials can be well characterized by the two first factors, while all essential sampling process characteristics can be summarized by combinations of the latter three. We here present simulations based on an experimental design that varies all five factors. Within the framework of the Theory of Sampling, the empirical Total Sampling Error is a function of the fundamental sampling error and the grouping and segregation error interacting with a specific sampling process. We here illustrate absolute and relative sampling variance levels resulting from a wide array of simulated repeated samplings and express the effects by pertinent lot mean estimates and associated Root Mean Squared Errors/sampling variances, covering specific combinations of materials’ heterogeneity and typical sampling procedures as used in current science, technology and industry. Factors, levels and interactions are varied within limits selected to match realistic materials and sampling situations that mimic, e.g., sampling for genetically modified organisms; sampling of geological drill cores; sampling during off-loading 3-dimensional lots (shiploads, railroad cars, truckloads etc.) and scenarios representing a range of industrial manufacturing and production processes. A new simulation facility “SIMSAMP” is presented with selected results designed to show also the wider applicability potential. This contribution furthers a general exposé of all essential effects in the regimen covered by “correct sampling errors”, valid for all types of materials in which non-bias sampling can be achieved. 相似文献
110.