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Flexible Hierarchical TiO2/Fe2O3 Composite Membrane with High Separation Efficiency for Surfactant‐Stabilized Oil‐Water Emulsions 下载免费PDF全文
Globally, efficient oil‐water separation for surfactant‐stabilized oil‐water emulsions has been in urgent demand. The current options available for separation are neither sustainable nor resistant to fouling. Herein, we introduce a hierarchically nanostructured TiO2/Fe2O3 composite membrane, which is capable of separating surfactant‐stabilized oil‐water emulsions with high separation efficiency. The high oil rejection rate is contributed by the acquisition of an interconnected delicate network and underwater superoleophobic interface. Meanwhile, its self‐cleaning function promote the facile recovery of the contaminated membrane. Furthermore, the mechanical flexible characteristic of the TiO2/Fe2O3 composite membrane widens its applicability in industrial employment. Thanks to these properties, this novel membrane can be considered as a practical option for treating surfactant‐stabilized oil‐water emulsions. 相似文献
114.
激光水下距离选通成像系统要想获得有效的目标图像,必须精确地给出合适的触发信号和控制接收器ICCD的门控延迟时间和选通门宽等门控参数。针对这一关键问题,设计了不存在成像距离盲区的激光器电源提供源触发信号的外触发方式,并应用二分查找的方法确定成像系统的门控参数,利用实验确定的门控参数,获得了5至23m水下不同深度的有效目标激光图像48张。获取的水下激光目标图像的信噪比可达10dB以上,可满足目标探测的实际应用要求。 相似文献
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Mohamed K. Watfa Samir Selman Hovig Denkilkian 《International Journal of Communication Systems》2010,23(4):485-506
As over 70% of the earth's surface is covered by water, it is desirable to deploy underwater sensor networks (UWSNs) to support oceanic research. UWSNs use acoustic waves and are characterized by long and variable propagation delays, intermittent connectivity, limited bandwidth and low bit rates. Energy savings have always been the primary concern in wireless sensor network protocols; however, there are applications where the latency and throughput are prioritized over energy efficiency and are so significant that the application would not be able to satisfy its requirements without them. Although existing duty‐cycle MAC protocols are power efficient, they introduce significant end‐to‐end delivery latency, provide poor throughput and are not suitable for the challenging environment of a UWSN. In this paper, we utilize CDMA as the underlying multiple access technique, due to its resilience to multi‐path and Doppler's effects prevalent in underwater environments. We propose UW‐MAC, a CDMA‐based power‐controlled medium access protocol that uses both transmitter‐based and receiver‐based CDMA inside a formed cluster, and uses a TDMA schedule to make the cluster heads communicate with the base station. Our MAC algorithm targets the latency and throughput needs in addition to its ability to increase the overall network lifetime. We discuss the design of UW‐MAC, and provide a head‐to‐head comparison with other protocols through extensive simulations focusing on the performance in terms of latency, throughput, and energy consumption. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
117.
The one-dimensional ballistic aggregation process is considered when the initial mass density or the initial particle velocities vanish outside of a finite or semi-infinite interval. In all cases, we compute the mass distributions in closed analytical form and study their long time asymptotics. The relevant length scales are found different (of the order t, t
2/3, t
1/2) if, at the initial time, particles occupy a finite (or semi-infinite) interval and if a finite (or infinite) number of them are set into motion. 相似文献
118.
Curing kinetics of anisotropic conductive adhesive film 总被引:1,自引:0,他引:1
Polymer-based conductive-adhesive materials have become widely used in many electronic packaging interconnect applications,
such as chip-on-glass, chip-on-flex, etc. Among all the conductive-adhesive materials, anisotropic conductive adhesive film
(ACF) is an attractive interconnect material because of its fine pitch capability. Anisotropic conductive-adhesive film is
a thermosetting, epoxy matrix impregnated with a small amount of electrically conductive particles. During component assembly,
the epoxy resin is cured to provide mechanical connection, and the conducting medium provides electrical connection in the
z direction. The thermal cure process is critical to develop the ultimate electrical and mechanical properties of the ACF.
In this paper, the curing reaction of ACF was studied with a differential scanning calorimeter (DSC) under isothermal conditions
in the range of 120–180°C. An autocatalyzed kinetic model was used to describe the curing reaction. The rate constant and
the reaction orders were determined and used to predict the progress of the curing reaction. A good agreement is found between
the proposed kinetic model and the experimental reaction-rate data. The reaction-rate constants were correlated with the isothermal
temperature by the Arrhenius equation. The glass-transition temperature also has been studied as a function of cure degree
and moisture absorption. 相似文献
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V. I. Boyarintsev A. K. Lednev A. S. Prudnikov A. S. Savin E.O. Savina 《Fluid Dynamics》2004,39(6):972-978
The data of a laboratory experiment to observe the small perturbations of a free surface by a thin hydrofoil profile moving horizontally in water are presented and compared with the calculation results obtained for a hydrofoil modeled by a system of distributed sources and sinks within the framework of the small-wave approximation.Translated from Izvestiya Rossiiskoi Academii Nauk, Mekhanika Zhidkosti i Gaza, No. 6, 2004, pp. 145–152.Original Russian Text Copyright – 2004 by Boyarintsev, Lednev, Prudnikov, Savin, and Savina. 相似文献