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1.
In the last two decades protection against electrostatic hazards became a very important topic. The increase in the range of possible faults fast automated systems and complex fault analysis is required.The tools of artificial intelligence and expert systems have been applied successfully on this field and this paper aims to take a step further. While giving some insight to the currently used tools, another AI method, the 'support vector machines' are introduced in this paper. Besides a brief review on SVMs they are introduced to the SCOUT system, a novel approach to electrostatic hazard management.  相似文献   
2.
The main aim of the project reported in this paper was twofold. One of the primary goals was to produce an extensive source of network data for bibliometric analyses of field dynamics in the case of Computer and Information Science. To this end, we rendered the raw material of the DBLP computer and infoscience bibliography into a comprehensive collection of dynamic network data, promptly available for further statistical analysis. The other goal was to demonstrate the value of our data source via its use in mapping Computer and Information Science (CIS). An analysis of the evolution of CIS was performed in terms of collaboration (co-authorship) network dynamics. Dynamic network analysis covered three quarters of the XX. century (76 years, from 1936 to date). Network evolution was described both at the macro- and the mezo level (in terms of community characteristics). Results show that the development of CIS followed what appears to be a universal pattern of growing into a “mature” discipline.  相似文献   
3.
A simple one-pot, three-step synthetic route to chiral 1,3-amino alcohols and 1,3-diols has been established. Considering the overall stereocontrol of the synthetic protocol, the first and key step is an enantioselective β-boration of α,β-unsaturated imines and ketones, respectively. The enantioselectivity provided by the Cu(I) catalyst modified with Josiphos- and Mandyphos-type ligands has been examined. The oxidative substitution of the boryl unit with a hydroxyl group proceeds with complete retention of configuration at the C(β)-atom. In parallel, the stoichiometric reduction of the imino or carbonyl group provides a second stereogenic centre. Depending on the nature of the reducing reagent, exceptionally high diastereoselectivity is achieved, especially for syn-1,3-amino alcohols and 1,3-diols.  相似文献   
4.
γ-spectra and excitation functions of the100Mo(p, nγ)100Tc reaction were measured in the 1.2–3.6 MeV proton energy range by using thick, enriched targets, Ge(Li) and low energy photon (hyperpure Ge) spectrometers. These detectors were used inγγ-coincidence experiments, too. Conversion electron spectrum measurements were performed by means of a superconducting magnet transporter Si(Li) spectrometer (SMS) atE p =4 MeV and multipolarities of some transitions have been determined. Based on the experimental results a level scheme of100Tc has been constructed. Level energies of100Tc were calculated on the basis of the parabolic rule, derived from the cluster-vibration model.  相似文献   
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6.
The modeling of the lightning channel's propagation has been a major issue in lightning protection. Several solutions are already existing based on different assumptions revealing different properties of the lightning, including return strokes, the orientation point (and distance), and several other factors. The path of the lightning channel however is very hard to model using the physical equations and laws only, since a lot of the boundary conditions and starting conditions are unknown. Thus for these purposes the probabilistic approach is practically used. In this paper a lightning path simulation method is shown based on a probabilistic approach. The lightning path is mainly influenced by the electric field, and the existence of the start electrons. These conditions can't always be calculated, thus in many cases a probabilistic model shall be used. The model proposed in this article has a modular approach, it consists of several components. Each of these components can be improved based on existing theories, and empirical data, and this makes this simulation method – besides the realization – “open source”, as the components can be improved individually. At this stage of the development, many lightning parameters are yet omitted, but the model structure of course allows further improvement on this field as well.  相似文献   
7.
Boron compounds have been traditionally regarded as "Lewis acids" preferring to accept electrons rather than donate them in the course of their reactions but current examples of unusual reactivity between tricoordinated boranes and electrophilic sites suggest a new conceptual context for the boryl moieties, based on their nucleophilic character which can be enhanced depending on the substituents on boron.  相似文献   
8.
From the ripe fruits of red mamey (Pouteria sapota), two new carotenoids, 3′‐deoxycapsorubin and 3,3′‐dideoxycapsorubin, were isolated and identified based on their UV/VIS, CD, 1H‐NMR, and mass spectral data.  相似文献   
9.
Complex networks have been extensively studied in the past 15 years and with increasing details. However, research on the temporal dynamics of complex networks is largely a new territory yet to map out. The present volume presents a collection of papers dealing with various aspects of the problem and this editorial introduces the field as well as the papers.  相似文献   
10.
3-Substituted and 3,4-disubstituted pyrroline nitroxides containing an ethynyl group or two ethynyl groups were achieved by the reaction of a paramagnetic aldehydes with dimethyl (1-diazo-2-oxopropyl)phosphonate (Bestmann–Ohira reagent). The new compounds containing an ethynyl group were found to be useful building blocks in Sonogashira coupling, cyclization, and cycloaddition reactions producing potentially “azido-specific” cross-linking spin labels, paramagnetic ligands, and polyradical scaffolds.  相似文献   
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