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11.
以氨基树脂585-1、0.5 s硝化棉为成膜物质,再加入助溶剂、催干剂,并以无水乙醇作为稀释剂进行溶合,制得一种醇溶性纸张上光涂料。讨论了树脂、硝化棉、助溶剂、催干剂等组分及其用量对涂料性能的影响。结果表明:树脂、硝化棉、助溶剂、催干剂配比为4∶10∶21∶1时,上光涂料的干燥速率最大,涂膜综合性能良好。 相似文献
12.
Recently, Internet energy efficiency is paid more and more attention. New Internet architectures with more energy efficiency were proposed to promote the scalability in energy consumption. The eontent-eentrie networking (CCN) proposed a content-centric paradigm which was proven to have higher energy efficiency. Based on the energy optimization model of CCN with in-network caching, the authors derive expressions to tradeoff the caching energy and the transport energy, and then design a new energy efficiency cache scheme based on virtual round trip time (EV) in CCN. Simulation results show that the EV scheme is better than the least recently used (LRU) and popularity based cache policies on the network average energy consumption, and its average hop is also much better than LRU policy. 相似文献
13.
In-network caching is one of the most important issues in content centric networking (CCN), which may extremely influence the performance of the caching system. Although much work has been done for in-network caching scheme design in CCN, most of them have not addressed the multiple network attribute parameters jointly during caching algorithm design. Hence, to fill this gap, a new in-network caching based on grey relational analysis (GRA) is proposed. The authors firstly define two newly metric parameters named request influence degree (RID) and cache replacement rate, respectively. The RID indicates the importance of one node along the content delivery path from the view of the interest packets arriving The cache replacement rate is used to denote the caching load of the node. Then combining hops a request traveling from the users and the node traffic, four network attribute parameters are considered during the in-network caching algorithm design. Based on these four network parameters, a GRA based in-network caching algorithm is proposed, which can significantly improve the performance of CCN. Finally, extensive simulation based on ndnSIM is demonstrated that the GRA-based caching scheme can achieve the lower load in the source server and the less average hops than the existing the betweeness (Betw) scheme and the ALWAYS scheme. 相似文献
14.
Because of its potential applications in agriculture, environment monitoring and so on, wireless underground sensor network(WUSN) has been researched more and more extensively in recent years. The main and most important difference of WUSN to terrestrial wireless sensor network(WSN) is the channel characteristics, which determines the design methodology of it. In this paper, the propagation character of electromagnetic(EM) wave in the near surface WUSN is analyzed, as well as the path loss model of it is given. In addition, the influence of human's ankle to the channel characteristics of near surface WUSN is investigated by electromagnetic theory analysis, simulation and experiment. A novel path loss model of near surface WUSN which takes the interference of human's ankle into consideration is proposed. It is verified that the existing of human above the WUSN system may cause additional attenuation to the signal of near surface WUSN which propagates as lateral wave along the ground. Moreover, the relation of the attenuation and operating frequency is deduced, which gives a reference to extend the frequency band applied in WUSN. 相似文献
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16.
以丙烯酰胺(AM)和工业单体二甲基二烯丙基氯化铵(DMDAAC)为原料,过硫酸铵(APS)和亚硫酸氢钠(RH)复合物为引发体系,采取一次性加料方法,以特征黏度为考核指标,对几种阳离子度二甲基二烯丙基氯化铵与丙烯酰胺的共聚物PDA进行了制备工艺研究。通过正交优化等实验方法考察了单体起始质量分数、引发剂用量和聚合反应温度3个因素对选定的每一种阳离子度PDA共聚合反应结果的影响,得到了制备系列化具不同阳离子度PDA的各自最佳点的制备工艺条件,比较了在各阳离子度条件下,最佳制备工艺点时单体起始质量分数、引发剂用量和聚合反应温度的变化规律。结果表明,对于制备5%、10%、20%、30%和50%阳离子度的PDA产物,当单体起始质量分数分别为16%、18%、25%、35%和65%,引发剂用量占单体的质量分数分别为8.62×10-5、8.82×10-5、7.35×10-5、5.40×10-5和9.19×10-5,聚合反应温度分别为25、30、30、30℃和25℃时,特征黏度可分别达到17.0、15.0、11.6、9.0 dL/g和6.2 dL/g。此外还对共聚产物PDA进行了红外光谱结构表征。该工艺简单方便、清洁安全,适合于工业化生产。 相似文献
17.
对二合一石墨盐酸合成炉进行了多项技术改造,系统运行更加稳定、可靠,解决了废气污染环境的问题.对各项改造措施进行了介绍. 相似文献
18.
脉冲编码调制(pulse code modulation,PCM)是最基本和最常用的模拟信号数字化方法.由于抗干扰能力强,被广泛应用于数字通信领域.本文在介绍了PCM编码原理基础上,以LabVIEW软件为平台对PCM编译码的方法和过程仿真.仿真软件可实现多种信号类型的PCM编译码实现,为人们理解PCM编译码提供了简单、... 相似文献
19.
针对移动小波树数据流异常检测算法的不足,提出了一种改进的移动小波树异常检测方法,利用比率阈值去除颠簸数据的干扰,提高了检测精度;利用二分查找检测算法,提高了检测的效率;结合实时增量更新算法满足了数据流在线处理的要求;改进了阈值设定方法,可实现双边异常检测。用射线数据和电能质量扰动数据进行仿真实验,结果验证了方法的有效性。 相似文献
20.
苏丹红Ⅰ多克隆抗体的制备研究 总被引:1,自引:0,他引:1
研究制备抗苏丹红Ⅰ的多克隆抗体.采用混合酸酐法合成免疫抗原苏丹红Ⅰ明胶,按照常规免疫程序免疫新西兰大白兔制备抗苏丹红Ⅰ多克隆抗体.采用酶联免疫吸附法鉴定抗血清中抗苏丹红Ⅰ多克隆抗体效价.结果表明,苏丹红Ⅰ抗体的效价为1:8 000,可用于苏丹红Ⅰ的免疫学检测. 相似文献