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41.
In the past decade, remarkable progress has been made in the domain of augmented reality/virtual reality (AR/VR). The need for realistic and immersive augmentation has propelled the development of haptics interfaces-enabled AR/VR. The haptics interfaces facilitate direct interaction and manipulation with both real and virtual objects, thus augmenting the perception and experiences of the users. The level of augmentation can be significantly improved by thermal stimulation or sensing, which facilitates a higher degree of object identification and discrimination. This review discusses the thermal technology-enabled augmented reality and summarizes the recent progress in the development of different thermal technology such as thermal haptics including thermo-resistive heater and Peltier devices, thermal sensors including resistive, pyroelectric, and thermoelectric sensors, which can be utilized to improve the realism of augmentation. The fundamental mechanism, design strategies, and the rational guidelines for the adoption of these technologies in AR/VR is explicitly discussed. The conclusion provides an outlook on the existing challenges and outlines the future roadmap for the realization of next-generation thermo-haptics enabled augmented reality. 相似文献
42.
The development of immersive virtual reality (IVR) applications for design reviews is a major trend in the design field. While many different applications have been developed, there is little consensus on the functionalities necessary for these applications. This paper proposes a classification scheme for IVR functionalities related to design reviews (DRs), combining conceptual-to-empirical and empirical-to-conceptual strategies. The classification scheme consists of eight class categories (Input, Representation, Navigation, Manipulation, Collaboration, Edit, Creation, and Output), 22 class subcategories, and 55 classes. The classification scheme has been validated by analysing several commercial IVR applications for DRs. As part of the classification scheme development, Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was utilised to review 70 articles that develop IVR applications for DRs. The results from systematic literature reviews suggest the development of solutions that integrate several class categories, are better connected to current design workflows, include various design information, support a DR planning cycle, and support distributed work. The proposed classification scheme helps to orient the future development of IVR applications for DRs and provides a framework to systematically accumulate evidence on the effect of such applications on DRs. 相似文献
43.
为了更好模拟横断山在气象、植被、土壤、水分等垂直地带性影响下的水文过程,本文采用分布式流域水文模型 WEP,提出反映空间分异特征的垂直带参数化方案,并选择横断山流域 14 个水文控制断面 1960—2015 年的逐月径流数据进行了模拟验证。结果显示,垂直带参数化方案较好地模拟了横断山区的水循环过程;通过两种对照方案和垂直带参数化方案的对比表明,“垂直带参数化方案”比“普通的参数方案”的 NS 提高 0.03、RE 降低1%,比“均一化参数方案”的 NS 提高 0.3、RE 降低 19.6%。通过考虑参数的垂直变化影响,能够提高模型模拟效果,且可更好地反映气象、植被、土壤、水分等信息的垂直地带性,弥补以往水文模型对参数的垂直变化描述不足的问题。 相似文献
44.
《Journal of the European Ceramic Society》2014,34(1):63-68
The phase stability and thermophysical properties of InFeO3(ZnO)m (m = 2, 3, 4, 5) compounds were investigated, which are a general family of homologous layered compounds with general formula InFeO3(ZnO)m (m = 1–19). InFeO3(ZnO)m (m = 2, 3, 4, 5) ceramics were synthesized using cold pressing followed by solid-state sintering. They revealed an excellent thermal stability after annealing at 1450 °C for 48 h. No phase transformation occurred during heating to 1400 °C. InFeO3(ZnO)3 exhibited a thermal conductivity of 1.38 W m−1 K−1 at 1000 °C, which is about 30% lower than that of 8 wt.% yttria stabilized zirconia (8YSZ) thermal barrier coatings. The thermal expansion coefficients (TECs) of InFeO3(ZnO)m bulk ceramics were in a range of (10.97 ± 0.33) × 10−6 K−1 to (11.46 ± 0.35) × 10−6 K−1 at 900 °C, which are comparable to those of 8YSZ ceramics. 相似文献
45.
46.
The equilibrium and dynamic surface tension of three sulfosuccinate surfactants at the air/aqueous solution interface were investigated. Wilhelmy plate method was used to determine critical micelle concentration (CMC) and the equilibrium surface tension (γ eq). The dynamic surface tensions in the range 10–100 s were measured by maximum bubble pressure method. The well-known Ward–Tordai equation was employed to analyze the adsorption of the sulfosuccinate surfactants. The parameters and effective diffusion coefficients (D eff) of dynamic surface tension have been calculated and analyzed. The equilibrium surface tension results showed that disodium laureth (3) sulfosuccinate (AEO3-SS), disodium laureth (6) sulfosuccinate (AEO6-SS) and disodium alkyl ethoxy glucoside sulfosuccinate (AEG-SS) are surfactants possessing strong surface activity, adsorbing to the interface rapidly and their γ eq values were in the range 25–32 mN/m. CMC of the three surfactants increases with the number of hydrophilic groups and AEO3-SS has the lowest CMC. According to the values of some dynamic surface tension parameters, AEG-SS is the most hydrophilic surfactant of them and AEO3-SS is energetically more favorable to adsorb to the interface than the others. According to Ward–Tordai equation, the D eff values were calculated, the adsorption mechanism was diffusion controlled at short times and toward the end good evidence was found for an activated-diffusion mechanism with an energy barrier. 相似文献
47.
Guanhong Xu Yue Chen Kun Shen Xiuzhen Wang Fei Li Yan He 《International journal of molecular sciences》2014,15(5):8553-8569
Neuronal nitric oxide synthase (nNOS) plays an important role in neurotransmission and smooth muscle relaxation. Selective inhibition of nNOS over its other isozymes is highly desirable for the treatment of neurodegenerative diseases to avoid undesirable effects. In this study, we present a workflow for the identification and prioritization of compounds as potentially selective human nNOS inhibitors. Three-dimensional pharmacophore models were constructed based on a set of known nNOS inhibitors. The pharmacophore models were evaluated by Pareto surface and CoMFA (Comparative Molecular Field Analysis) analyses. The best pharmacophore model, which included 7 pharmacophore features, was used as a search query in the SPECS database (SPECS®, Delft, The Netherlands). The hit compounds were further filtered by scoring and docking. Ten hits were identified as potential selective nNOS inhibitors. 相似文献
48.
Jing Li Nan Zhou Kun Luo Wei Zhang Xinru Li Chuanfang Wu Jinku Bao 《International journal of molecular sciences》2014,15(9):15994-16011
Angiogenesis is the growth of new capillaries from existing blood vessels that supply oxygen and nutrients and provide gateways for immune surveillance. Abnormal vessel growth in term of excessive angiogenesis is a hallmark of cancer, inflammatory and eye diseases. VEGFR-2 (vascular endothelial growth factor receptor 2) dominating the process of angiogenesis has led to approval of therapeutic inhibitors and is becoming a promising target for anti-angiogenic drugs. Notwithstanding these successes, the clinical use of current VEGFR-2 blockers is more challenging than anticipated. Taking axitinib as a reference drug, in our study we found three potent VEGFR-2 inhibitors (ZINC08254217, ZINC08254138, and ZINC03838680) from natural derivatives. Each of the three inhibitors acquired a better grid score than axitinib (−62.11) when docked to VEGFR-2. Molecular dynamics simulations demonstrated that ZINC08254217– and ZINC08254138–VEGFR-2 complexes were more stable than axitinib. Similar to bind free energy for axitinib (−54.68 kcal/mol), such for ZINC03838680, ZINC08254217, and ZINC08254138 was −49.37, −43.32, and −32.73 kcal/mol respectively. These results suggested these three compounds could be candidate drugs against angiogenesis, with comparable VEGFR-2 binding affinity of axitinib. Hence findings in our study are able to provide valuable information on discovery of effective anti-angiogenesis therapy. 相似文献
49.
Target Hopping as a Useful Tool for the Identification of Novel EphA2 Protein–Protein Antagonists 下载免费PDF全文
Dr. Daniele Pala Dr. Simonetta Russo Dr. Riccardo Castelli Dr. Iftiin Hassan‐Mohamed Dr. Carmine Giorgio Dr. Alessio Lodola 《ChemMedChem》2014,9(1):67-72
Lithocholic acid (LCA), a physiological ligand for the nuclear receptor FXR and the G‐protein‐coupled receptor TGR5, has been recently described as an antagonist of the EphA2 receptor, a key member of the ephrin signalling system involved in tumour growth. Given the ability of LCA to recognize FXR, TGR5, and EphA2 receptors, we hypothesized that the structural requirements for a small molecule to bind each of these receptors might be similar. We therefore selected a set of commercially available FXR or TGR5 ligands and tested them for their ability to inhibit EphA2 by targeting the EphA2‐ephrin‐A1 interface. Among the selected compounds, the stilbene carboxylic acid GW4064 was identified as an effective antagonist of EphA2, being able to block EphA2 activation in prostate carcinoma cells, in the micromolar range. This finding proposes the “target hopping” approach as a new effective strategy to discover new protein–protein interaction inhibitors. 相似文献
50.
Predicted Ligands for the Human Urotensin‐II G Protein‐Coupled Receptor with Some Experimental Validation 下载免费PDF全文
Dr. Soo‐Kyung Kim Prof. William A. Goddard III Dr. Kyu Yang Yi Dr. Byung Ho Lee Chae Jo Lim Prof. Bartosz Trzaskowski 《ChemMedChem》2014,9(8):1732-1743
Human Urotensin‐II (U‐II) is the most potent mammalian vasoconstrictor known. 1 Thus, a U‐II antagonist would be of therapeutic value in a number of cardiovascular disorders. 2 Here, we describe our work on the prediction of the structure of the human U‐II receptor (hUT2R) using GEnSeMBLE (GPCR Ensemble of Structures in Membrane BiLayer Environment) complete sampling Monte Carlo method. With the validation of our predicted structures, we designed a series of new potential antagonists predicted to bind more strongly than known ligands. Next, we carried out R‐group screening to suggest a new ligand predicted to bind with 7 kcal mol?1 better energy than 1‐{2‐[4‐(2‐bromobenzyl)‐4‐hydroxypiperidin‐1‐yl]ethyl}‐3‐(thieno[3,2‐b]pyridin‐7‐yl)urea, the designed antagonist predicted to have the highest affinity for the receptor. Some of these predictions were tested experimentally, validating the computational results. Using the pharmacophore generated from the predicted structure for hUT2R bound to ACT‐058362, we carried out virtual screening based on this binding site. The most potent hit compounds identified contained 2‐(phenoxymethyl)‐1,3,4‐thiadiazole core, with the best derivative exhibiting an IC50 value of 0.581 μM against hUT2R when tested in vitro. Our efforts identified a new scaffold as a potential new lead structure for the development of novel hUT2R antagonists, and the computational methods used could find more general applicability to other GPCRs. 相似文献