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21.
为开发牛血肽相关功能性产品提供理论依据,作者研究了含铁牛血肽对于大鼠缺铁性贫血的治疗效果。以低铁鼠粮饲喂初离乳雌性SD大鼠3周,建立缺铁性贫血模型。以含铁鼠粮为正常对照,以生血宁为阳性对照,用含铁牛血肽灌胃至血红蛋白质质量浓度达到100 g/L以上。结果表明:含铁牛血肽显著地改善了缺铁性贫血引起的大鼠体质量以及白细胞、红细胞、血红蛋白和红细胞压积等血常规指标的下降,同时改善铁代谢指标血清铁和血清铁蛋白。低剂量牛血肽效果相当于生血宁,中高剂量牛血肽效果优于生血宁,证明饲喂含铁牛血肽可以改善大鼠缺铁性贫血。 相似文献
22.
在市场上逐步推广的液晶模块(LCM)生产中,其LCD系列驱动电路的封装工艺主要采用裸芯片的COB(chip on Board)封装方式。文中通过总结自行设计和加工的LCD系列电路在应用厂商批量使用过程中出现的COB封装问题,对COB的工艺流程、COB工艺中的关键工艺——键合以及主要的失效点以及常见的失效原因进行分析,并结合在实际推广过程中问题的解决方法,对LCD系列驱动电路和其他芯片在COB应用中主要出现的键合不良、边缘铝层颜色异常、钝化孔残留、键合参数、COB环境等方面问题加以整理归纳,并提出了可行的解决办法。 相似文献
23.
Nanoengineering Hybrid Supramolecular Multilayered Biomaterials Using Polysaccharides and Self‐Assembling Peptide Amphiphiles 下载免费PDF全文
Developing complex supramolecular biomaterials through highly dynamic and reversible noncovalent interactions has attracted great attention from the scientific community aiming key biomedical and biotechnological applications, including tissue engineering, regenerative medicine, or drug delivery. In this study, the authors report the fabrication of hybrid supramolecular multilayered biomaterials, comprising high‐molecular‐weight biopolymers and oppositely charged low‐molecular‐weight peptide amphiphiles (PAs), through combination of self‐assembly and electrostatically driven layer‐by‐layer (LbL) assembly approach. Alginate, an anionic polysaccharide, is used to trigger the self‐assembling capability of positively charged PA and formation of 1D nanofiber networks. The LbL technology is further used to fabricate supramolecular multilayered biomaterials by repeating the alternate deposition of both molecules. The fabrication process is monitored by quartz crystal microbalance, revealing that both materials can be successfully combined to conceive stable supramolecular systems. The morphological properties of the systems are studied by advanced microscopy techniques, revealing the nanostructured dimensions and 1D nanofibrous network of the assembly formed by the two molecules. Enhanced C2C12 cell adhesion, proliferation, and differentiation are observed on nanostructures having PA as outermost layer. Such supramolecular biomaterials demonstrate to be innovative matrices for cell culture and hold great potential to be used in the near future as promising biomimetic supramolecular nanoplatforms for practical applications. 相似文献
24.
制备了不同类型的单皂和复皂润滑脂,测定了其理化性能。采用分子模拟技术对润滑脂滴点进行了初步预测,并计算了润滑脂中各种金属皂分子间氢键键长和分子体积模量。结果表明,复合钙皂和复合锂皂的分子体积模量分别大于钙皂和锂皂的分子体积模量。金属皂分子体积模量与其所形成的润滑脂的滴点呈对应关系,即分子体积模量大的,其形成的润滑脂滴点也高,反之则反。采用分子模拟技术可以从分子的层次指导润滑脂的研究。 相似文献
25.
利用催化加氢热解技术提取沉积 有机质中生物标志化合物 总被引:4,自引:2,他引:4
利用催化加氢热解技术提取了高演化沉积有机质中共价键结合的生物标志化合物,探讨了干酪根催化加氢热解反应机理,并考察了反应产物分布和影响反应的关键变量.实验表明,程序升温固定床催化加氢热解反应条件:温度上限为520℃,升温速率为5℃/min,氢压大于10MPa,氢气流量为5L/min,分散型催化剂为MoS2(Mo的质量分数为1%).实验结果表明,催化加氢热解对提取高产率、结构重排少的干酪根中共价键结合的生物标志化合物有独特作用,该方法可以应用于有机地球化学领域. 相似文献
26.
This paper describes the results of structural, electronic and elastic properties of silicon nitride(in its high-pressure P61 and P62 phases) through the first-principles calculation combined with an ultra-soft pseudopotential. The computed equilibrium lattice constants agree well with the experimental data and the theoretical results. The strongest chemical bond(N–Si bond) shows a covalent nature with a little weaker ionic character. P61-Si3N4 is more stable than P62-Si3N4 due mainly to the fact that the shorter N–Si bond in the P61 phase allows stronger electron hybridizations. We have also predicted the phase stability of Si3N4 using the quasi-harmonic approximation, in which the lattice vibration and phonon effect are both considered. The results show that the β→P61 phase transition is very likely to occur at 42.9 GPa and 300 K. The reason why the β→P61→δ phase transitions had never been observed is also discussed. 相似文献
27.
Yu Hin Chan Jang-Kyo Kim Deming Liu Peter C. K. Liu Yiu Ming Cheung Ming Wai Ng 《Journal of Electronic Materials》2004,33(2):146-155
The process windows are presented for low-temperature Au wire bonding on Au/Ni/Cu bond pads of varying Au-layer thicknesses
metallized on an organic FR-4 printed circuit board (PCB). Three different plating techniques were used to deposit the Au
layers: electrolytic plating, immersion plating, and immersion plating followed by electrolytic plating. Wide ranges of wire
bond force, bond power, and bond-pad temperature were used to identify the combination of these processing parameters that
can produce good wire bonds, allowing the construction of process windows. The criterion for successful bonds is no peel off
for all 20 wires tested. The wire pull strengths and wire deformation ratios are measured to evaluate the bond quality after
a successful wire bond. Elemental and surface characterization techniques were used to evaluate the bond-pad surfaces and
are correlated to wire bondability and wire pull strength. Based on the process windows along with the pull strength data,
the bond-pad metallization and bonding conditions can be further optimized for improved wire bondability and product yields.
The wire bondability of the electrolytic bond pad increased with Au-layer thickness. The bond pad with an Au-layer thickness
of 0.7 μm displayed the highest bondability for all bonding conditions used. The bondability of immersion bond pads was comparable
to electrolytic bond pads with a similar Au thickness. Although a high temperature was beneficial to wire bondability with
a wide process window, it did not improve the bond quality as measured by wire pull strength. 相似文献
28.
29.
研究了A位Ba2+取代对(Ca1-xBax)[(Li1/3Nb2/3)0.95Zr0.15]O3+δ (0≤x≤0.2,CBLNZ)陶瓷的微观结构及微波介电特性的影响.当0≤x≤0.025时,体系为单一钙钛矿相,随Ba2+含量的增加,谐振频率温度系数(τf)由-9.4×10-6/℃增加到18×10-6/℃,而品质因数(Q)先增大;当x=0.025时,开始下降.用键价理论分析了谐振频率温度系数随B位键价的变化关系.当x(Ba2+)=2.5%时,陶瓷微波介电性能最佳,即介电常数εr=34.3,品质因数与频率的乘积Q·f =13 400 GHz,τf =-2.1×10-6/℃. 相似文献
30.