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91.
92.
基于宽带毫米波工作体制的雷达目标识别方法探讨 总被引:1,自引:0,他引:1
对基于宽带毫米波工作体制的雷达目标特征获取和识别方法进行了综合分析和探讨.表明:在毫米波照射下,雷达目标可模型化为由多个散射中心组成的扩展目标;只要发射信号有足够的带宽,就可以从回波信号中获得各散射中心的空间分布、类型等特征;仿真结果说明,这种方法对高频区复杂目标的识别是有效的. 相似文献
93.
An integrated process based on simultaneous solid-liquid extraction and liquid membrane separation is proposed for recovery and isolation of valuable species from botanicals. This integration provides complete exhausting of the solid material even in the case of very low solubility of the specified solute in the extracting solvent. Selectivity of the liquid membrane ensures a preferential transport of the desired solute from the native extract into the strip solution, while the other co-extracted species remain predominantly in the native extract. 相似文献
94.
E. Gomez 《Chemical engineering science》2006,61(14):4595-4604
The influence of oxygen transport rate on Rhodococcus erythropolis cultures has been studied in a stirred tank bioreactor under different transport and uptake conditions. Oxygen uptake rate has been measured by applying a modified dynamic method and a kinetic model is proposed, obtaining the kinetic parameter values: specific maintenance and yield coefficients. The volumetric mass transfer coefficients under inert conditions, kLa, and during the bioprocess, KLa, have been determined. The values obtained are different and a biological enhancement factor E, has been considered. These parameters have been predicted by the theoretical model and good agreement with experimental data under the conditions studied has been found. The oxygen limitation has been expressed by a modified dimensionless Damköhler number, Da, the relationship between transport and biological reaction rates. This number decreases with increasing stirrer speed; that is, when mass transport resistance decreases. The efficiency of oxygen utilization can be determined by a film effectiveness factor, η. The effectiveness factor was found to be a strong function of Damköhler number and decrease with increasing Da. Furthermore, oxygen concentration into culture depends on the mass transfer and consumption rates. The theoretical model proposed is able to reasonably predict the evolution of dissolved oxygen concentration with time of cultivation. 相似文献
95.
96.
陆晓君 《安徽水利水电职业技术学院学报》2003,3(4):56-59
介绍在VB6.0中如何使用API函数和自定义函数实现屏幕分辨率和色彩度的获取和更改。 相似文献
97.
震源延迟叠加技术及应用效果 总被引:2,自引:0,他引:2
延迟叠加爆炸是针对高分辨率和深层地震勘探而提出来的一种激发方式。这种激发方式能在保证地震分辨率的前提下有效提高地震波能量 ,在地震波的入射角范围内 ,有效克服非球形炸药激发引起的地震波传播的方向性。应用弹性波动力学对多级延迟爆炸进行理论研究 ,结合实际试验资料 ,研究了延迟爆炸情况下激发参数对地震波能量、主频、频宽等的影响。从几何地震学出发 ,分析了不同时间激发的地震波在地下空间中的干涉情况 ,对其能量传播的方向性进行了研究。理论分析和试验效果表明 ,延迟叠加震源与相同药量的普通震源相比 ,激发地震波的主频高 ,频带宽 ,增强了下传能量 ,降低了次生干扰 ,在高分辨率和深层地震勘探中具有明显的优势。 相似文献
98.
Fincham Frank D.; Beach Steven R. H.; Davila Joanne 《Canadian Metallurgical Quarterly》2007,21(3):542
Does forgiveness predict later conflict resolution in married couples? Twelve-month follow-up data on conflict resolution were collected from the couples studied by F. D. Fincham, S. R. Beach, and J. Davila (see record 2004-11293-007), who had provided earlier reports of forgiveness and conflict resolution. For wives, the positive dimension of forgiveness or benevolence predicted husbands' later reports of better conflict resolution controlling for initial levels of conflict resolution. This finding was independent of wives' marital satisfaction and the degree of hurt engendered by husbands' transgressions. For husbands, the only predictor of wives' reports of later conflict resolution was initial level of conflict resolution. The findings are discussed in terms of the direction of effect between forgiveness and conflict resolution and of the mechanisms that might link them. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
The wireless connectivity in pervasive computing has ephemeral character and can be used for creating ad hoc networks, sensor
networks, connection with RFID (Radio Frequency Identification) tags etc. The communication tasks in such wireless networks
often involve an inquiry over a shared channel, which can be invoked for: discovery of neighboring devices in ad hoc networks,
counting the number of RFID tags that have a certain property, estimating the mean value contained in a group of sensors etc.
Such an inquiry solicits replies from possibly large number of terminals n. This necessitates the usage of algorithms for resolving batch collisions (conflicts) with unknown conflict multiplicity n. In this paper we present a novel approach to the problem of collision resolution for batch conflicts. We show how the conventional
tree algorithms for collision resolution can be used to obtain progressively accurate estimation of the multiplicity. We use
the estimation to propose a more efficient binary tree algorithm, termed Estimating Binary Tree (EBT) algorithm. The EBT algorithm
is suited for implementation when the conflicting nodes are passive, such as e.g. RFID tags. We extend the approach to design
the Interval Estimation Conflict Resolution (IECR) algorithm. For n→∞ we prove that the efficiency achieved by IECR for batch arrivals is identical with the efficiency that Gallager’s FCFS
algorithm achieves for Poisson packet arrivals. For finite n, the simulation results show that IECR is, to the best of our knowledge, the most efficient batch resolution algorithm reported
to date. 相似文献
100.
大规模定制为生产带来了变革和影响。针对新的生产方式的要求,根据推动大规模定制的过程方法和技术来分析他们对于质量控制产生的影响和要求,给出了大规模定制条件下的质量控制系统的建议,并给出了一个简要的系统模型。 相似文献