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991.
文化要素与文化内涵是旅游度假景区规划中需要重点关注的设计要素。本文试图通过句容“曼地茅山”国际旅游度假景区规划这一案例,从“文化探源、内涵表现、要素延展”等层面,探讨如何合理有效利用旅游度假景区的文化要素及其相关信息,并在此基础上有效组织与整合景区内的文化景观与生态景观资源,从而构建功能合理、景观优美、交通流畅、文化脉络清晰的旅游度假景区,借此最终达到景区及其周边区域整体机能良性发展的目标。 相似文献
992.
分析了电液复合式水下分配单元的基本构成与功能。为提供多个水下设备的阀门执行器同时动作所需的液压动力,提出液压分配单元的管路结构优化设计方案,并对其流动情况进行了模拟仿真验证。提出以光功率分配器为核心的电气分配单元设计方案,建立基于光功率分配器的下行控制信号传输模型,并采用Optisystem软件模拟验证了其可行性。 相似文献
993.
基于光纤陀螺仪的基本原理与动力定位的结构和原理,通过光纤陀螺仪的数学模型和动力定位的基本数学模型,分析该设备在海洋石油动力定位中应用的可行性。结果表明:在近海范围,光纤陀螺仪自身就可以实现作业船只的姿态测量和动力定位;而在深海地区,光纤陀螺仪可以作为位置测量系统的核心器件,实现更加复杂的船舶动力定位。 相似文献
994.
Design and synthesis of organosoluble and transparent polyimides containing bulky substituents and noncoplanar structures
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A new diamine monomer, 3,3′‐diisopropyl‐4,4′‐diaminophenyl‐4″‐phenyltouene, was designed, synthesized, and then polymerized with five commercial dianhydrides to obtain a series of novel polyimides via a one‐step method. The obtained polymers showed excellent solubility in most common solvents, even in low‐boiling solvents, such as chloroform, dichloromethane, and tetrahydrofuran. They exhibited a high thermal stability with the glass‐transition temperature in the range 262–318°C and 10% weight loss temperatures in the range 464–488°C under a nitrogen atmospheres. Meanwhile, these polymer films also displayed a high optical transparency with a cutoff wavelength in the range 305–365 nm; prominent mechanical properties with a tensile strength of 65.6–94.9 MPa, a Young's modulus of 1.6–2.8 GPa, and an elongation at break of 9.3–13.7%; a low dielectric constant in the range of 2.91–3.18 at 1 MHz; and an outstanding hydrophobicity with a contact angle above 90.6°. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43266. 相似文献
995.
Stepwise cure and properties of silicone resin for high‐ultraviolet‐transmission optical elements
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Zhiyong Lv Chonggang Wu Jing Li Xiao Fang Dongdong Yu Huchuan Qin Peng Yu Xuhuang Chen 《应用聚合物科学杂志》2016,133(16)
A new high‐ultraviolet (UV)‐transmission silicone‐resin polymeric material was prepared via curing during hydrosilylation of tetramethyltetravinylcyclotetrasiloxane with tetramethylcyclotetrasiloxane by a liquid‐surface supernatant method, using a stepwise heating program to avoid spontaneous combustion of the reaction mixture. The relationships were investigated in detail between reactive groups, cross‐linking density, mechanical and UV‐transmission properties. For this purpose, UV transmittance and dynamic mechanical properties, respectively, of the silicone resin were measured with UV–visible spectrophotometry and dynamic mechanical thermal analysis. In addition, surface roughness was evaluated with an atomic force microscope as well as an interferometer. The curing process was monitored by Fourier transform infrared spectroscopy and rotational rheometry. The cyclic silicone oils were compared with linear ones in structure and product properties. The results indicated that stepwise temperature control during curing process was particularly indispensible due to the presence of active Si? H bonds, and that the silicone resin of high modulus, high UV transmittance (92.7%) and low surface‐roughness was largely homogeneous in cross‐linking points distribution. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43308. 相似文献
996.
Synthesis and characterization of a novel fluorene‐alt‐carbazole polymer to host green,blue, and red phosphorescence
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A novel fluorene‐alt‐carbazole polymer host Poly(9,9‐dioctyl‐9H‐fluorene‐2,7‐diyl‐alt‐N‐tetrahydropyran‐3,6‐carbazole) (PFCz), composed of N‐tetrahydropyran‐3,6‐carbazole and 9,9‐dioctyl‐2,7‐fluorene in the polymer backbone, was synthesized by Suzuki coupling. The PFCz possesses good thermal stability and proper lowest unoccupied molecular orbital (LUMO)/highest occupied molecular orbital (HOMO) energy levels to facilitate the injection and transport of electrons and holes. Upon doping with blue, green, and red phosphors, red ‐ green ‐ blue (R‐G‐B) phosphorescent devices hosted by PFCz have been fabricated and investigated. In contrast to those of blue and green devices, the red devices give better performances with a maximum luminous efficiency of 4.88 cd/A and a maximum power efficiency of 1.85% at 149.84 cd/m2, due to favorable triplet energy level (ET) of PFCz for red phosphor, bis(2‐methyldibenzo[f,h]quinoxaline)(acetylacetonate)iridium(III) [Ir(MDQ)2(acac)]. Additionally, with different doped concentrations of Ir(MDQ)2(acac), the PFCz‐related red devices emit nearly pure red light with Commission Internationale de L'Eclairage (CIE) coordinates of (0.57, 0.38), (0.60, 0.38), (0.61, 0.38), and (0.62, 0.38), which were very close to the standard red (0.66, 0.34) by the National Television System Committee. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43234. 相似文献
997.
Poly[6‐(2,6‐bis(1′‐methylbenzimidazolyl)pyridin‐4‐yloxy)hexyl acrylate] (PBIP) and its terbium (III) complex (PBIP‐Tb3+): Homopolymerization,optical, and magnetic performance
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Poly[6‐(2,6‐bis(1′‐methylbenzimidazolyl)pyridin‐4‐yloxy)hexyl acrylate] (PBIP) and its terbium complex (PBIP‐Tb3+) were prepared and characterized by 1H NMR and FT‐IR. The optical properties of PBIP‐Tb3+ complex were characterized by UV–vis spectroscopy and fluorescence spectroscopy. Both polymer PBIP and PBIP‐Tb3+ complex show good thermal stability. The magnetic property of PBIP‐Tb3+ complex was measured as a function of temperature (5–300 K) at 30 kOe and as a function of an external field (?50 to 50 kOe) at 5 K. Magnetic hysteresis loop of PBIP‐Tb3+ complex at 5 K shows typical “S” shape and PBIP‐Tb3+ complex is soft ferromagnetic. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44249. 相似文献
998.
Enhancement of physical and optical performances of polycarbonate‐based diffusers for direct‐lit LED backlight unit by incorporation of nanoclay platelets
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Using twin‐extrusion compounding followed by compression molding processes, polycarbonate/clay nanocomposite optical diffusers with highly intercalated and exfoliated nanostructure could be prepared for application in direct‐lit LED backlight unit. The incorporation of nanoclay platelets with an appropriate level of content substantially improved thermal resistance, as well as thermo‐mechanical, and mechanical flexural properties. The optical property of luminance uniformity with respect to both location and viewing angle was also enhanced by the load of nanoclay platelets along with silicone bead, probably due to efficient scattering and diffusion action of the nanoclay. However, excess loading of nanoclay had insignificant effect on the improvement of properties for the nanocomposite diffusers. In addition, the presence of nanoclay platelets in the PC matrix effectively suppressed the moisture absorption rate, suggesting the feasibility of avoiding the warpage phenomena of the optical diffuser during use. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42973. 相似文献
999.
Ultrathin buffer layer at organic/organic interface for managing the recombination profile in organic light‐emitting diodes: Metal versus dielectric buffer
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Davood Kalhor Ezeddin Mohajerani Omid HashemiPour Akram SalehiKian Mohsen Shojaeifar Mohammad Rasoul Babaei 《应用聚合物科学杂志》2016,133(36)
We report on the utilization of an ultrathin buffer layer at the organic/organic (O/O) interface to enhance device efficiency in organic light‐emitting diodes. Two different kinds of buffer layers are examined: metal and dielectric. It is shown that employment of an ultrathin Ag layer with a thickness of 1–2 nm enhances the device performance, while a MgF2 dielectric buffer cannot affect the device properties considerably. In particular, the turn‐on voltage of the device with an appropriate buffer layer is reduced about 3 V, its current efficiency increases by a factor of more than three, and the power efficiency increases by a factor of more than five in comparison to the control device when a Ag buffer layer is introduced at the O/O interface. By employment of the buffer layer at the interface, an accumulation of current carriers appears within the device that redistribute the recombination profile toward the interior part of the emissive layer. Also, morphological examinations reveal that distinguishable phase segregation occurs in the blend of the hole‐transport layer. In particular, the polymer component remains at the surface and facilitates the hole transport into the successive layers. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43894. 相似文献
1000.
Takuya Orihashi Toshihiro Nakamura Sadao Adachi 《Journal of the American Ceramic Society》2016,99(9):3039-3046
The europium titania materials, pyrochlore Eu2Ti2O7 and orthorhombic Eu2TiO5, were synthesized from a mixture of Eu2O3 and TiO2 using the solid‐state reaction method. The structural and optical properties of these titania materials were investigated using X‐ray diffraction analysis, photoluminescence (PL) analysis, PL excitation (PLE) spectroscopy, and diffuse reflectance spectroscopy. Temperature dependence of the PL intensity was measured between T = 20 and 450 K and analyzed on the basis of various theoretical models. A remarkable increase in the PL intensity with increasing T was observed in these titania materials at higher temperatures, above ~140 K, and well explained by a trap/reservoir model. Interestingly, a dramatic decrease in the electric‐dipole emission component relative to the magnetic‐dipole one was observed in Eu2Ti2O7 above T ~ 140 K. The schematic energy‐level diagram for Eu3+ in the Eu2Ti2O7 host was proposed for the sake of a better understanding of the PL and PLE processes in this type of phosphorescent material. 相似文献