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991.
Yuya Ishii Taiki Nobeshima Heisuke Sakai Keisho Omori Sei Uemura Mitsuo Fukuda 《大分子材料与工程》2018,303(1)
Amorphous electrically actuating submicron fiber waveguides are promising building blocks for creating novel opto‐electromechanical devices. In this study, waveguiding and electrically actuating properties of the waveguides composed of racemic poly(lactic acid) and a dye are investigated. The fibers have mean diameters of <0.4 µm, and each fiber demonstrates subwavelength waveguiding with a loss coefficient of 1.5 × 10?4–8.3 × 10?4 µm?1 at 0.63 µm wavelength. Light propagates with a near‐light speed group velocity between wavelengths of 0.59 and 0.63 µm, where the fraction of power inside the core is 0.13–0.28. The fiber mat thicknesses change in response to both the polarity and the magnitude of an applied voltage, similar to the inverse‐piezoelectric effect. The estimated values for both the apparent piezoelectric constant (29 000 × 10?12 m V?1) and Young's modulus (1.5 kPa) indicate a high degree of electricity actuation and a soft mat. Extremely small, soft, and electrically actuating waveguides can produce novel opto‐electromechanical devices. 相似文献
992.
为了能有效解决柔性基底体声波谐振器热稳定性不足及功率容量不足等问题,该文提出了一种新型的基于柔性基底的薄膜体声波谐振器。该谐振器的硅衬底上开设有一定数量的垂直上凸型结构,该结构既能有效抑制寄生模量,又能减小器件最高稳态温度和最大热应力。通过有限元分析软件Comsol Multiphics对谐振器进行仿真,结果表明,器件每增加一个上凸型结构,其最高稳态温度下降了4 ℃,最大热应力下降了1×104 GPa。与以往的柔性基底薄膜体声波谐振器相比,它具有更好的热传导能力和热应力稳定性。 相似文献
993.
GONG Bo LAI Zuhan Northeast University of Technology Shenyang ChinaNIINOMI Mitsuo KOBA YASHI Toshiro Toyohashi University of Technology Toyohashi Japan Department of Physics Northeast University of Technology Shenyang China 《金属学报(英文版)》1993,6(2):121-124
A new process to refine the microstructure of α+βtvpe Ti alloys was developed by usinghydrogen as a temporary alloying element.It involves hydrogenating the alloys below thehydrogenated β transus temperature about 0-40 K,air cooling to room temperature and thendehydrogenating at 948 K.Ti-6AI-4V and Ti-5AI-2.5Fe alloys treated hy this new processshow much refined microstructures,and the yield strength,ultimate strength as well as theelongation increase 8—15,5—13 and 7—14% respectively 相似文献
994.
995.
1 INTRODUCTIONCu basedshapememoryalloys (SMA )werestudiedbymanyauthorsinrecentyears[1~ 13 ] .Itisconvincedthattheshapememoryeffectisass 相似文献
996.
对"均衡凝固技术"几个基本问题的讨论--球墨铸铁缩松、缩孔问题探讨(三) 总被引:2,自引:2,他引:2
就球铁件缩松、缩孔问题对“均衡凝固技术”几个基本问题进行讨论。指出作为该理论的基础的缩胀叠加图不完全符合实际情况;石墨化膨胀提前不利于消除缩松、缩孔。对薄小件缩松倾向大的原因、冒口是否应当靠近和离开铸件热节、是否可以早于铸件热节凝同、冷铁能否使膨胀提前,以及顶注的优点等问题提出不同的看法。认为按比例进行的均衡凝同不可能实现,而且依靠膨胀提前达到的均衡凝同对防止缩松、缩孔不利。 相似文献
997.
998.
Kun Zhai Da‐Shan Shang Yi‐Sheng Chai Gang Li Jian‐Wang Cai Bao‐Gen Shen Young Sun 《Advanced functional materials》2018,28(9)
The cross‐coupling between electric polarization and magnetization in multiferroic materials provides a great potential for creating next‐generation memory devices. Current studies on magnetoelectric (ME) applications mainly focus on ferromagnetic/ferroelectric heterostructures because single‐phase multiferroics with strong magnetoelectric coupling at room temperature are still very rare. Here a type of nonvolatile memory device is presented solely based on a single‐phase multiferroic hexaferrite Sr3Co2Fe24O41 which exhibits nonlinear magnetoelectric effects at room temperature. The principle is to store binary information by employing the states (magnitude and sign) of the first‐order and the second‐order magnetoelectric coefficients (α and β), instead of using magnetization, electric polarization, and resistance. The experiments demonstrate repeatable nonvolatile switch of α and β by applying pulsed electric fields at room temperature, respectively. Such kind of memory device using single‐phase multiferroics paves a pathway toward practical applications of spin‐driven multiferroics. 相似文献
999.
Au Catalyzed Carbon Diffusion in Ni: A Case of Lattice Compatibility Stabilized Metastable Intermediates 下载免费PDF全文
Jian‐Xin Kang Dong‐Feng Zhang Gen‐Cai Guo Hai‐Jun Yu Li‐Hua Wang Wei‐Feng Huang Ru‐Zhi Wang Lin Guo Xiao‐Dong Han 《Advanced functional materials》2018,28(21)
Nickel is a crucial catalyst for its excellent performance in active carbon atom–related catalysis such as hydrocarbon steam reforming and 1D carbon nanostructures preparation. The carbon diffusion activity in Ni is of critical importance in understanding the catalytic behavior and thereby the performance optimization. However, the carbonization process is still vague because of the hardly identified intermediates. In this paper, the metastable intermediates of nickel carbonization process are successfully stabilized by taking advantage of the epitaxial growth to elevate the structure transformation energy barrier. X‐ray diffraction, high‐resolution transmission electron microscopy, and synchrotron X‐ray absorption near edge structure data evidence the face‐centered cubic (fcc)? Ni x C nature of the intermediates and thus an fcc? Ni x C‐intermediated nickel carbonization process from fcc? Ni to hexagonal close‐packed (hcp)‐Ni3C is revealed, which is also confirmed by the Vienna ab initio simulation package calculation from the viewpoint of energy evolution. To the best of the knowledge, it is the first time to report the identification of the fcc? Ni x C. More importantly, the introduction of Au is found promoted the catalytic growth of graphitic carbon using either oleylamine or C2H4 as carbon resource. The Au@Ni‐based hybrid catalysts exhibit lower reaction temperature and much higher carbon output than pure Ni. 相似文献
1000.
Carbon Diffusion: Au Catalyzed Carbon Diffusion in Ni: A Case of Lattice Compatibility Stabilized Metastable Intermediates (Adv. Funct. Mater. 21/2018) 下载免费PDF全文