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91.
92.
93.
Yu Chen Weimin Zhao Quanhai Zhang Guangzhi Yang Jianming Zheng Wei Tang Qunjie Xu Chunyan Lai Junhe Yang Chengxin Peng 《Advanced functional materials》2020,30(19)
Ternary layered oxide materials have attracted extensive attention as a promising cathode candidate for high‐energy‐density lithium‐ion batteries. However, the undesirable electrochemical degradation at the electrode–electrolyte interface definitively shortens the battery service life. An effective and viable approach is proposed for improving the cycling stability of the LiNi1/3Co1/3Mn1/3O2 cathode using lithium difluorophosphate (LiPO2F2) paired with fuoroethylene carbonate (FEC) as co‐additives into conventional electrolytes. It is found that the co‐additives can greatly reduce the interface charge transfer impedance and significantly extend the life span of LiNi1/3Co1/3Mn1/3O2//Li (NMC//Li) batteries. The developed cathode demonstrates exceptional capacity retention of 88.7% and remains structural integrity at a high current of 5C after 500 cycles. Fundamental mechanism study indicates a dense, stable fluorinated organic–inorganic hybrid cathode‐electrolyte interphase (CEI) film derived from LiPO2F2 in conjunction with FEC additives on the surface of NMC cathode material, which significantly suppresses the decomposition of electrolyte and mitigates the dissolution of transition metal ions. The interfacial engineering of the electrode materials stabilized by the additives manipulation provides valuable guidance for the development of advanced cathode materials. 相似文献
94.
Chen L. Crnic M. Zonghe Lai Johan Liu 《Electronics Packaging Manufacturing, IEEE Transactions on》2002,25(4):273-278
Liquid crystal polymer (LCP) has potentially a very wide application as substrate material in electronic packaging applications because of its unique advantages. The work in this paper was performed to realize the metallization of LCP for the purpose of board fabrication, and to study the adhesion between deposited copper and LCP. A homogenous electroless plated copper layer on LCP with 4 to 5 /spl mu/m thickness was achieved, while it increased up to 40 /spl mu/m with the subsequent electroplating. The timescale of etching, deposit ion rate, and pH value were gradually changing during the plating process and the influences on copper layer quality were investigated. The adhesion force of the copper-LCP layer system was measured by a shear-off-method. Scanning electron microscopy (SEM) was used to check the surface morphology after etching and the interface after shearing on both the backside of the copper layer and the LCP side. The relationship between the shear-off adhesion of copper and the time of chemical etching before plating was examined, and the optimal etching time is discussed. Heat treatment after plating was used, and it was shown that this significantly improved the adhesion strength. 相似文献
95.
Wei Kuang Lai Mu‐Lung Weng Yo‐Ho Lin 《Wireless Communications and Mobile Computing》2014,14(7):704-716
A hop‐aware and energy‐based buffer management scheme (HEB) is proposed in this paper. HEB can provide better quality of service to packets with real‐time requirements and improve MANET power efficiency. In our algorithm, the buffer is divided into real‐time and non‐real‐time partitions. We consider the number of hops passed, the power levels of the transmitting node, the predicted number of remaining hops, and waiting time in the buffer to determine packet transmission priority. In addition, specialized queue management and a probabilistic scheduling algorithm are proposed to decrease retransmissions caused by packet losses. Mathematical derivations of loss rates and end‐to‐end delays are also proposed. Coincidence between mathematical and simulation results is also shown. Finally, the HEB is compared with first in first out, random early detection, and hop‐aware buffering scheme. Simulation results show that the proposed algorithm reduces loss rates, power consumption, and end‐to‐end delays for real‐time traffic, considerably improving the efficiency of queue management in MANET. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
96.
Zhi Jiang Yang Wang Shuoguo Yuan Lu Shi Ni Wang Jie Xiong Wenhui Lai Xuanyu Wang Feiyu Kang Wei Lin Ching Ping Wong Cheng Yang 《Advanced functional materials》2019,29(9)
Commercial aluminium electrolyte capacitors (AECs) are too large for integration in future highly integrated electronic systems. Supercapacitors, in comparison, possess a much higher capacitance per unit volume and can be embedded as passive capacitors to address such challenges in electronics scaling. However, the slow frequency response (<101 Hz) typical of supercapacitors is a major hurdle to their practical application. Here, it is demonstrated that 1T‐phase MoSe2 nanosheets obtained by laser‐induced phase transformation can be used as an electrode material in embedded micro‐supercapacitors. The metallic nature of MoSe2 nanosheet‐based electrodes provides excellent electron‐ and ion‐transport properties, which leads to an unprecedented high‐frequency response (up to 104 Hz) and cycle stability (up to 106 cycles) when integrated in supercapacitors, and their power density can be ten times higher than that of commercial AECs. Furthermore, fabrication processes of the present device are fully compatible with system‐in‐package device manufacturing to meet stringent specifications for the size of embedded components. The present research represents a critical step forward in in‐package and on‐chip applications of electrolytic capacitors. 相似文献
97.
98.
Nitride-Based ultraviolet metal-semiconductor-metal photodetectors with a low-temperature GaN layer 总被引:1,自引:0,他引:1
J. K. Sheu C. J. Kao M. L. Lee W. C. Lai L. S. Yeh G. C. Chi S. J. Chang Y. K. Su J. M. Tsai 《Journal of Electronic Materials》2003,32(5):400-402
The GaN metal-semiconductor-metal (MSM) ultraviolet (UV) photodetectors with a low-temperature (LT)-GaN layer have been demonstrated.
It was found that we could achieve a two orders of magnitude smaller, photodetector-dark current by introducing a LT-GaN layer,
which could be attributed to the larger Schottky-barrier height between the Ni/Au metal contact and the LT-GaN layer. It was
also found that photodetectors with the LT-GaN layer could provide a larger photocurrent to dark-current contrast ratio and
a larger UV-to-visible rejection ratio. The maximum responsivity was found to be 3.3 A/W and 0.13 A/W when the photodetector
with a LT-GaN layer was biased at 5 V and 1 V, respectively. 相似文献
99.
There has been a steadily increasing interest in using electrically conductive adhesives as interconnecting materials in electronics
manufacturing. In this paper, several anisotropic conductive adhesive (ACA) pastes were formulated, which consist of diglycidyl
ether of bisphenol F or diglycidyl ether of bisphenol A as polymer matrix, imidazoles as curing agents, and different sizes
of silver (Ag) powders or gold (Au)-coated polymer spheres as conductive particles. The effects of ACA resin and different
curing agents, as well as different conductive particles, on flexible substrate of the flip-chip joint were studied. The results
show that the size and type of different conductive particles have very limited influence on an ACA flip-chip joint. The ACA
resin as well as the curing agent can affect the reliability of the joint. The same results can be applied for the failure
analysis of ACA flip-chip technology. 相似文献
100.
Zhou Zhang Lai Mun Wong Hou Xiao Wang Zhi Peng Wei Wei Zhou Shi Jie Wang Tom Wu 《Advanced functional materials》2010,20(15):2511-2518
In‐plane growth of Mg2SiO4 nanowires on Si substrates is achieved by using a vapor transport method with Au nanoparticles as catalyst. The self‐assembly of the as‐grown nanowires shows dependence on the substrate orientation, i.e., they are along one, two, and three particular directions on Si (110), (100), and (111) substrates, respectively. Detailed electron microscopy studies suggest that the Si substrates participate in the formation of Mg2SiO4, and the epitaxial growth of the nanowires is confined along the Si <110> directions. This synthesis route is quite reliable, and the dimensions of the Mg2SiO4 nanowires can be well controlled by the experiment parameters. Furthermore, using these nanowires, a lithography‐free method is demonstrated to fabricate nanowalls on Si substrates by controlled chemical etching. The Au nanoparticle catalyzed in‐plane epitaxial growth of the Mg2SiO4 nanowires hinges on the intimate interactions between substrates, nanoparticles, and nanowires, and our study may help to advance the developments of novel nanomaterials and functional nanodevices. 相似文献