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991.
The recent miniaturization and increased complexity of electrical devices have increased the influence of impurities on device performance, especially the influence of small conductive particles with a size on the order of micrometers. Therefore, the inspection of devices during the manufacturing process has become important. In this study, changes in the resonance properties of a microwave cavity were used to detect a metal particle. The decrease in the resonant frequency for a 100‐µm stainless steel sphere was about 0.1 MHz, which was less than 1 ppm of the resonant frequency used. This frequency change is too small to detect directly in the output of a particle detector. Transmission measurements (the scattering parameter S21) at a frequency that was a few megahertz higher than the resonant frequency where the S21 changes sharply were used to magnify signal changes resulting from the introduction of a small conductive particle. A resonant frequency of 13.3 GHz and a frequency 3 MHz higher were chosen for obtaining measurements in the present study. By applying a filtering technique, it was shown that the minimum detectable sphere size is around 50 µm. This sensitivity was experimentally shown to be uneven along the long axis of the cavity. The unevenness was related to the electrical field strength of the standing wave at the resonant frequency. For practical industrial inspection of devices, multiple frequencies should be employed in view of the present discussion. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(2): 61–67, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22490 相似文献
992.
Masayuki Ishihara Satoko Kishimoto Makoto Takikawa Hidemi Hattori Shingo Nakamura Masafumi Shimizu 《International journal of molecular sciences》2015,16(5):11785-11803
Low molecular weight heparin (LMWH)/protamine (P) nano/micro particles (N/MPs) (LMWH/P N/MPs) were applied as carriers for heparin-binding growth factors (GFs) and for adhesive cells including adipose-derived stromal cells (ADSCs) and bone marrow-derived mesenchymal stem cells (BMSCs). A mixture of LMWH and P yields a dispersion of N/MPs (100 nm–3 μm in diameter). LMWH/P N/MPs can be immobilized onto cell surfaces or extracellular matrix, control the release, activate GFs and protect various GFs. Furthermore, LMWH/P N/MPs can also bind to adhesive cell surfaces, inducing cells and LMWH/P N/MPs-aggregate formation. Those aggregates substantially promoted cellular viability, and induced vascularization and fibrous tissue formation in vivo. The LMWH/P N/MPs, in combination with ADSCs or BMSCs, are effective cell-carriers and are potential promising novel therapeutic agents for inducing vascularization and fibrous tissue formation in ischemic disease by transplantation of the ADSCs and LMWH/P N/MPs-aggregates. LMWH/P N/MPs can also bind to tissue culture plates and adsorb exogenous GFs or GFs from those cells. The LMWH/P N/MPs-coated matrix in the presence of GFs may provide novel biomaterials that can control cellular activity such as growth and differentiation. Furthermore, three-dimensional (3D) cultures of cells including ADSCs and BMSCs using plasma-medium gel with LMWH/P N/MPs exhibited efficient cell proliferation. Thus, LMWH/P N/MPs are an adequate carrier both for GFs and for stromal cells such as ADSCs and BMSCs, and are a functional coating matrix for their cultures. 相似文献
993.
Clusters of Phospholipid Vesicles as Platforms for Glucose Oxidase‐Catalyzed Reaction in a Bubble‐Column Bioreactor
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Makoto Yoshimoto Yuki Sakakida Ryota Tamura Tomotaka Natsume Tomoaki Ikeda 《化学工程与技术》2016,39(6):1130-1136
Clusters of negatively charged liposomes encapsulated with glucose oxidase were prepared in the presence of Ca2+ and used to catalyze the oxidation of glucose in an external loop airlift bubble column. The clusters exhibited higher catalytic activity compared to nonclustered glucose oxidase‐containing liposomes (GOLs) when the liposome membranes were incorporated with cholesterol. The clusters were structurally altered in shear flow to give sufficient interfacial area accessible to glucose. The reactivity of GOL clusters could be modulated on the basis of lipid composition of the membranes which affected the mode of interaction among liposomes through Ca2+. Part of GOL clusters could be separated from the reaction mixture by centrifugation, which would be advantageous for reusing liposomal catalysts. The liposome clusters can be the platforms to regulate the catalytic performance of glucose oxidase in the airlift. 相似文献
994.
995.
Tomoyo Andachi Naoki Yamamoto Atsuo Tamura Keisuke Tominaga 《Journal of Infrared, Millimeter and Terahertz Waves》2014,35(1):147-157
We have investigated the low-frequency spectra of a phospholipid bilayer composed of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) by terahertz time-domain spectroscopy (THz-TDS). We focused on the temperature and hydration dependence of the low-frequency spectra of a gel-phase sample. The spectra of the dehydrated and hydrated samples showed shoulder bands at 45 and 30 cm-1, respectively. In contrast to the dehydrated sample, in the hydrated sample spectra the slope of the temperature change of the absorption coefficient increased sharply around 240 K. This result suggests that water molecules affect the change in the low-frequency dynamics. We obtained the absorption coefficient difference spectra for different hydration levels to clarify the mechanism of the spectral change. 相似文献
996.
Masafumi Tasaki Hiroko Yamamoto Taiyo Yoshioka Makoto Hanesaka Tran Hai Ninh Kohji Tashiro Hye Jin Jeon Kwang Bok Choi Hak Seung Jeong Hyun Hoon Song Moon Hor Ree 《Polymer》2014
Relationship between the chain conformation in the crystal lattice and the ultimate Young's modulus has been discussed on the basis of the crystal structural information revealed by the X-ray diffraction analysis for a series of arylate polyesters with long methylene segments (–[–COC6H4CO–O(CH2)mO–]n–). The X-ray structural analysis revealed that the molecular chains take the all-trans-zigzag conformations for all of the even-numbered polyesters and their model compounds as well as the odd-numbered polyesters with the methylene segmental length longer than (CH2)14. These chain conformations have been correlated well to the ultimate Young's modulus along the chain axis or the crystallite modulus Ec, which has been estimated experimentally by the X-ray diffraction method under a constant stress and also predicted theoretically using the X-ray-analyzed crystal structures on the basis of the molecular mechanics method. The Ec was found to show the minimum at around m = 4–6 and increased gradually with an increment of m and approached the crystallite modulus of polyethylene, 235 GPa (X-ray value) ∼ 316 GPa (calculate) at an infinite m value. This behavior of Ec as a function of the number of methylene segmental units m was reasonably interpreted by developing the theoretical equation of Ec for a simplified zigzag chain model composed of a repetition of two linear rods representing the benzene–ester and methylene segmental parts respectively. These findings may promise that the mechanical property of arylate polyester can be controlled by adjusting the methylene segmental length m. 相似文献
997.
Wu-Shung Fu Wei-Hsiang Wang Chung-Gang Li Makoto Tsubokura 《Numerical Heat Transfer, Part B: Fundamentals》2017,71(1):66-83
Unstable phenomena induced by natural convection of parallel square plates are investigated numerically. The geometry belongs to the open boundary problem, and the compressibility of fluids is taken into consideration. The absorbing boundary condition and modified local one-dimensional inviscid relation method are adopted for open boundaries. Numerical methods of the Roe scheme, preconditioning, and dual time stepping matching the data-parallel lower-upper relaxation method are coordinated with multi-GPU implementation. Unstable phenomena of natural convection caused by the buoyancy force can be observed. Present results have good agreement with the experimental results in the overlap range of the existing study. 相似文献
998.
Yifei Du Kenji Aoki Makoto Sakamoto Kunihito Yamamori Hiroshi Furutani 《Artificial Life and Robotics》2017,22(1):17-23
Genetic algorithms (GAs) are stochastic optimization techniques, and the theoretical study of the process of GA evolution is very important in the application of GA. Mutation is one of most important operators in GA, and Markov chain theory has attracted researchers’ attention for the study of mutation. By applying Markov chain to study symmetric mutation model in GA, we have obtained the relation between the mutation rate and the evolution of the first order schema. This paper theoretically analyzes the effects of mutation rates on GA with asymmetric mutation, and studies the evolution and stationary distribution of the first order schema. This study focuses on effects of asymmetry to the linkage of loci, and shows the degree of asymmetry in mutation has a large effect on the evolution of the first order schema. 相似文献
999.
This paper discusses power flow analysis and DC capacitor voltage regulation of a modular multilevel cascaded converter (MMCC) based on double‐star chopper cells (DSCC). This analysis reveals the relationship between the circulating current through the DC link and the average power flowing out of or into each chopper cell. The DC component of the circulating current supplies half the active output power to the upper and lower strings of the chopper cells, while in contrast the fundamental frequency component transfers an amount of power between the upper and lower strings. Thus, the MDCC–DSCC can balance the capacitor voltages among the cells by controlling the amplitude of the fundamental frequency component of the circulating current. A new control method based on power flow analysis is employed, and its effectiveness is verified by circuit simulation. 相似文献
1000.
Makoto Hanabata 《Advanced functional materials》1994,4(2):75-82
The performance of novolac–diazonaphthoquinone-based positive-working resists is discussed in terms of the molecular weight distributions and microstructures of the novolac resins and the structural variations in the photoactive dissolution inhibitor. Modelling studies leading to recent improvements allosing the delineation of 0.35 μm line and space pattens by ensuring a focal depth of 105 μm are outlined. Consideration is also given to the new problems such as pivotal shift and halation that arise in the application of high-resolution photolithography using novolac–diazonaphthoquinone resists. 相似文献