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排序方式: 共有1021条查询结果,搜索用时 15 毫秒
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彭海文 《数字社区&智能家居》2011,(7)
该文先简要介绍了Android平台和Android平台的下的开发,并针对通话拦截和强插所需要的两个知识Broadcast Receiver和Telephony Manager类进行说明,再介绍如何通过AIDL及JAVA反射机制,使用隐藏的ITelephony接口,并研究了通话拦截和强插技术在Android下的实现,最后总结全文,并引出对Android权限管理的一些思考。 相似文献
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循环插入排序法 总被引:2,自引:0,他引:2
唐开山 《计算机工程与应用》2005,41(12):88-91
文章提出了一种循环插入的排序方法。给出了算法思想、算法描述、算法分析和实验结果。其理论意义是改进了一类时间复杂度为O(N2)排序法的时间复杂度,其实用价值是该排序法在一类时间复杂度为O(N2)排序法中排序效率较高的,其平均排序速度比直接插入排序法、选择排序法、冒泡排序快50%~63%。 相似文献
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为实现含分布式电源的电力系统实时仿真,研究了一种基于实时数字仿真器(RTDS)和现场可编程门阵列(FPGA)联合仿真平台的多速率实时仿真方法。采用局部延迟插入方法分解电力系统网络,并利用拟合法和外插法实施并行多速率接口电气量交互。为减小通信延时对仿真精度的影响,提出了一种FPGA数据发送适当早于RTDS数据发送的接口电气量异步交互方法。在RTDS和FPGA联合仿真平台上以50μs/1μs混合仿真步长实时仿真了一个含2个光伏发电的IEEE 5节点电力系统,并与PSCAD平台下的仿真数据进行对比,验证了所提联合仿真平台的可行性和实时仿真方法的准确性。 相似文献
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Guixiang Tang Xuanbo Zhong Wei Hong Jianfei Li Yue Shu Lulu Liu 《International journal of molecular sciences》2022,23(12)
Soybean cyst nematode (SCN, Heterodera glycines Ichinohe) causes an estimated economic loss of about USD 3 billion each year in soybean (Glycine max L.) production worldwide. Overexpression of resistance genes against SCN provides a powerful approach to develop SCN resistance cultivars in soybean. The clarification of molecular characterization in transformation events is a prerequisite for ecological risk assessment, food safety, and commercial release of genetically modified crops. Here, we generated transgenic events harboring the BCN (beet cyst nematode) resistance Hs1pro−1 gene using the Agrobacterium-mediated method in soybean, evaluated their resistance to SCN infection, and clarified the molecular characterization of one of the transformation events. Five independent and stable inheritable transformation events were generated by an Agrobacterium-mediated transformation method. SCN resistance tests showed the average number of developed females per plant and female index (FI) in T4 ZHs1-1, ZHs1-2, ZHs1-3, ZHs1-4, and ZHs1-5 transformation events were significantly lower than that in the nontransgenic control. Among these, the ZHs1-2 transformation event had the lowest number of developed females per plant and FI. Southern hybridization showed the exogenous target Hs1pro−1 gene was inserted in one copy and the Bar gene was inserted two copies in the ZHs1-2 transformation event. The exogenous T-DNA fragment was integrated in the reverse position of Chr02: 5351566–5231578 (mainly the Bar gene expression cassette) and in the forward position of Chr03: 17083358–17083400 (intact T-DNA, including Hs1pro−1 and Bar gene expression cassette) using a whole genome sequencing method (WGS). The results of WGS method and Southern hybridization were consistent. All the functional elements of exogenous T-DNA fragments were verified by PCR using specific primer pairs in the T5 and T6 ZHs1-2 transformation events. These results demonstrated that the overexpression of Hs1pro−1 gene enhanced SCN resistance, and provide an important reference for the biosafety assessment and the labeling detection in transformation event ZHs1-2. 相似文献
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大功率矿用防爆变频器大都采用PWM调制技术,使用IGBT作为开关器件,IGBT在开通和关断过程中会产生很大的du/dt,di/dt,由于线路中寄生电容和寄生电感的存在,会导致很严重的电磁干扰,严重影响系统安全稳定运行。对防爆变频系统EMI干扰源进行了分析建模,设计了防爆变频调速系统EMI滤波器,在分析阻抗失配对EMI滤波器插入损耗影响的基础上,建立带EMI滤波器的传导干扰的高频模型,通过有无EMI滤波器传导干扰频谱仿真图对比,验证了EMI滤波器对传导干扰的抑制作用。经过现场的实验测试,加入EMI滤波器后传导干扰得到很好的抑制,传导干扰频谱幅值在规定的范围内。 相似文献
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Development and Validation of an Artificial Mechanical Skin Model for the Study of Interactions between Skin and Microneedles 下载免费PDF全文
Sahan A. Ranamukhaarachchi Thomas Schneider Sarah Lehnert Lisa Sprenger Jonathon R. Campbell Iman Mansoor Jacqueline C. Y. Lai Kimit Rai Jan Dutz Urs O. Häfeli Boris Stoeber 《大分子材料与工程》2016,301(3):306-314
Microneedles are small needle‐like structures that are almost invisible to the naked eye. They have an immense potential to serve as a valuable tool in many medical applications, such as painless vaccination. Microneedles work by breaking through the stratum corneum, the outermost barrier layer of the skin, and providing a direct path for drug delivery into the skin. A lot of research has been presented over the past two decades on the applications of microneedles, yet the fundamental mechanism of how they interact, pressure, and penetrate the skin in its native state is worth examining further. As such, a major difficulty with understanding the mechanism of microneedle–skin interaction is the lack of an artificial mechanical human skin model to use as a standardized substrate. In this research news, the development of an artificial mechanical skin model based on a thorough mechanical study of fresh human and porcine skin samples is presented. The artificial mechanical skin model can be used to study the mechanical interactions between microneedles and skin, but not diffusion of molecules across skin. This model can assist in improving the performance of microneedles by enhancing the reproducibility of microneedle depth insertions for optimal drug delivery and biosensing.