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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Abstract This paper proposes a simple scheme to decompose an n×n nonpositive definite matrix, A, associated with simultaneous equations, A X = B, into a triple‐factors (lower triangular, diagonal, and upper triangular matrices), i.e., Å = L D U, without interchanging rows or columns of A, but with A expanded with new rows and new columns to an m×m matrix Å. Whenever a near‐zero diagonal element, say āii , is encountered and used as a pivoting element, an appropriate positive real number, say p, is added to this diagonal element, and a new term —pxk is also added to the i‐th equation, where xk is a new variable called “dummy variable'’. If we also add a new equation —pxi + pxk = 0 to enforce the new added variable xk equal to xi then the modified i‐th equation has the same effect as the original equation. Therefore, the original solution X can be found directly from the expanded solution of the modified expanded equation. The method is very useful in solving the following problems: (1) nonlinear problems near the limit state, (2) postbuckling analysis, (3) system equations with constraint conditions, and (4) getting eigenvectors from eigenvalues. 相似文献
992.
Phosphorene as a Polysulfide Immobilizer and Catalyst in High‐Performance Lithium–Sulfur Batteries 下载免费PDF全文
993.
994.
Abstract A novel filter is proposed to improve the noise robustness and discrimination capability for shift and scale invariant pattern recognition. This filter is a combination of mellin radial harmonic filter (RHF) and the bidimensional empirical mode decomposition. The basic principle of this method is to make use of partial reconstructions of the image by the relevant intrinsic mode functions corresponding to the most important structures of the image. A criterion is proposed to determine the proper number of intrinsic mode functions to be discarded for denoising by discussing the characteristic of the noise. The proposed filter provides a wider allowable scale change of the object. Within this range, the correlation peak intensity is relatively uniform even in the case of noise. This proposed filter has been tested experimentally to confirm the result from numerical simulations for cases with and without additive white Gaussian noise. 相似文献
995.
Carbon Nanotubes Disrupt Iron Homeostasis and Induce Anemia of Inflammation through Inflammatory Pathway as a Secondary Effect Distant to Their Portal‐of‐Entry 下载免费PDF全文
Juan Ma Ruibin Li Yin Liu Guangbo Qu Jing Liu Wenli Guo Haoyang Song Xinghong Li Yajun Liu Tian Xia Bing Yan Sijin Liu 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(15)
Although numerous toxicological studies have been performed on carbon nanotubes (CNTs), a few studies have investigated their secondary and indirect effects beyond the primary target tissues/organs. Here, a cascade of events are investigated: the initiating event and the subsequent key events necessary for the development of phenotypes, namely CNT‐induced pro‐inflammatory effects on iron homeostasis and red blood cell formation, which are linked to anemia of inflammation (AI). A panel of CNTs are prepared including pristine multiwall CNTs (P‐MWCNTs), aminated MWCNTs (MWCNTs‐NH2), polyethylene glycol MWCNTs (MWCNTs‐PEG), polyethyleneimine MWCNTs (MWCNTs‐PEI), and carboxylated MWCNTs (MWCNTs‐COOH). It has been demonstrated that all CNT materials provoke inflammatory cytokine interleukin‐6 (IL‐6) production and stimulate hepcidin induction, associated with disordered iron homeostasis, irrespective of exposure routes including intratracheal, intravenous, and intraperitoneal administration. Meanwhile, PEG and COOH modifications can ameliorate the activation of IL‐6‐hepcidin signaling. Long‐term exposure of MWCNTs results in AI and extramedullary erythropoiesis. Thus, an adverse outcome pathway is identified: MWCNT exposure leads to inflammation, hepatic hepcidin induction, and disordered iron metabolism. Together, the combined data depict the hazardous secondary toxicity of CNTs in incurring anemia through inflammatory pathway. This study will also open a new avenue for future investigations on CNT‐induced indirect and secondary adverse effects. 相似文献
996.
Philipp Scheiderer Matthias Schmitt Judith Gabel Michael Zapf Martin Stübinger Philipp Schütz Lenart Dudy Christoph Schlueter Tien‐Lin Lee Michael Sing Ralph Claessen 《Advanced materials (Deerfield Beach, Fla.)》2018,30(25)
The Mott transistor is a paradigm for a new class of electronic devices—often referred to by the term Mottronics—which are based on charge correlations between the electrons. Since correlation‐induced insulating phases of most oxide compounds are usually very robust, new methods have to be developed to push such materials right to the boundary to the metallic phase in order to enable the metal–insulator transition to be switched by electric gating. Here, it is demonstrated that thin films of the prototypical Mott insulator LaTiO3 grown by pulsed laser deposition under oxygen atmosphere are readily tuned by excess oxygen doping across the line of the band‐filling controlled Mott transition in the electronic phase diagram. The detected insulator to metal transition is characterized by a strong change in resistivity of several orders of magnitude. The use of suitable substrates and capping layers to inhibit oxygen diffusion facilitates full control of the oxygen content and renders the films stable against exposure to ambient conditions. These achievements represent a significant advancement in control and tuning of the electronic properties of LaTiO3+x thin films making it a promising channel material in future Mottronic devices. 相似文献
997.
Wanasinghe Arachchige Dumith Madushanka Jayathilaka Kun Qi Yanli Qin Amutha Chinnappan William Serrano‐García Chinnappan Baskar Hongbo Wang Jianxin He Shizhong Cui Sylvia W. Thomas Seeram Ramakrishna 《Advanced materials (Deerfield Beach, Fla.)》2019,31(7)
Together with the evolution of digital health care, the wearable electronics field has evolved rapidly during the past few years and is expected to be expanded even further within the first few years of the next decade. As the next stage of wearables is predicted to move toward integrated wearables, nanomaterials and nanocomposites are in the spotlight of the search for novel concepts for integration. In addition, the conversion of current devices and attachment‐based wearables into integrated technology may involve a significant size reduction while retaining their functional capabilities. Nanomaterial‐based wearable sensors have already marked their presence with a significant distinction while nanomaterial‐based wearable actuators are still at their embryonic stage. This review looks into the contribution of nanomaterials and nanocomposites to wearable technology with a focus on wearable sensors and actuators. 相似文献
998.
999.
Approaching Gas Phase Electrodeposition: Process and Optimization to Enable the Self‐Aligned Growth of 3D Nanobridge‐Based Interconnects 下载免费PDF全文
1000.
Abstract This study develops an analytical expression to describe the cyclic stress‐strain curve obtained from a series of fully‐reversed fatigue tests. A set of stress‐strain relationships is proposed to simulate the tensile branch of the stable hysteresis loop. The complete shape of the stable hysteresis loop is then constructed and the associated theoretical plastic work calculated by integrating the area within the enclosed curve. The theoretical plastic work is employed to predict the fatigue lives of the investigated materials on the basis of their respective stable plastic work per cyclelife curves. In this paper, the current mathematical derivations are based upon the endochronic theory of plasticity. The accuracy of the proposed set of stress‐strain relationships is verified by conducting fully‐reversed constant strain amplitude fatigue tests on AISI 316 and AISI 304 stainless steels. The experimental and simulation results are found to be in good agreement, hence confirming the accuracy of the proposed analytical stress‐strain relationships. Again, comparing the obverted and predicted fatigue lives, a good agreement is found between the two sets of results. 相似文献