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991.
This paper presents interactive stereoscopic artwork and an algorithm for natural artistic expression using hand-painted images expressed by the artist’s manual brush strokes. The system proposes a new interactive method that allows a viewer to experience the painting process representing the consecutive process of an actual artist’s oil painting. The combination of analog and digital techniques stimulates emotions of the audience. The system architecture is composed of the Kinect sensor, which recognizes the movement of the user, a module that generates real-time stereoscopic images, and a projection module that displays the generated image. The survey is conducted to evaluate the effects of the 3D modeling method and the artistic modeling method. The statistical result show that the proposed hand-painted method provides more artistic satisfaction to the viewers than the 3D modeling method. 相似文献
992.
Low-fidelity scale factor improves Bayesian multi-fidelity prediction by reducing bumpiness of discrepancy function 总被引:1,自引:0,他引:1
Chanyoung Park Raphael T. Haftka Nam H. Kim 《Structural and Multidisciplinary Optimization》2018,58(2):399-414
This study explores why the use of the low-fidelity scale factor can substantially improve the accuracy of the Bayesian multi-fidelity surrogate (MFS). It is shown analytically that the Bayesian MFS framework utilizes the scale factor to reduce the waviness and variation of the discrepancy function by maximizing the Gaussian process-based likelihood function. Less wavy functions are more accurately fitted, and variation reduction mitigates the effect of fitting error. Bumpiness is another way used to combine waviness and variation. Two examples, Borehole3 and Hartmann6, illustrated that indeed the Bayesian MFS reduced bumpiness using the scale factor. The finding may be useful for MFS using surrogates lacking uncertainty structure, so that likelihood is not an option, but bumpiness may be. 相似文献
993.
Data deduplication (dedupe for short) is a special data compression technique. It has been widely adopted to save backup time as well as storage space, particularly in backup storage systems. Therefore, most dedupe research has primarily focused on improving dedupe write performance. However, backup storage dedupe read performance is also a crucial problem for storage recovery. This paper designs a new dedupe storage read cache for backup applications that improves read performance by exploiting a special characteristic: the read sequence is the same as the write sequence. Consequently, for better cache utilization, by looking ahead for future references within a moving window, it evicts victims from the cache having the smallest future access. Moreover, to further improve read cache performance, it maintains a small log buffer to judiciously cache future access data chunks. Extensive experiments with real-world backup workloads demonstrate that the proposed read cache scheme improves read performance by up to 64.3% 相似文献
994.
Porous Hollow‐Structured LaNiO3 Stabilized N,S‐Codoped Graphene as an Active Electrocatalyst for Oxygen Reduction Reaction
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Tran Duy Thanh Nguyen Dinh Chuong Jayaraman Balamurugan Hoa Van Hien Nam Hoon Kim Joong Hee Lee 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(39)
A nanohybrid based on porous and hollow interior structured LaNiO3 stabilized nitrogen and sulfur codoped graphene (LaNiO3/N,S‐Gr) is successfully synthesized for the first time. Such a nanohybrid as an electrocatalyst shows high catalytic activity for oxygen reduction reaction (ORR) in O2‐saturated 0.1 m KOH media. In addition, it demonstrates a comparable catalytic activity, longer working stability, and much better alcohol tolerance compared with commercial Pt/C behavior in same experiment condition. The obtained results are attributed to synergistic effects from the enhanced electrocatalytic active sites on the rich pore channels of porous hollow‐structured LaNiO3 spheres and heteroatom doped efficiency on graphene structure. In addition, N,S‐Gr can meritoriously stabilize monodispersion of the LaNiO3 spheres, and act as medium bridging for high electrical conductivity, thereby providing large active surface area for O2 adsorption, accelerating reduction reaction, and improving electrochemical stability. Such a hybrid opens an interesting class of highly efficient non‐Pt catalysts for ORR in alkaline media. 相似文献
995.
Hong Yonghoon Kim Hee Jin Yang Daehee Lee Gaehang Nam Ki Min Jung Myung-Hwa Kim Young-Min Choi Sang-Il Seo Won Seok 《Nano Research》2017,10(8):2866-2880
We report a simple one-step approach for the synthesis of ~4 nm uniform and fully L10-ordered face-centered tetragonal (fct) FePt nanopartides (NPs) embedded in ~60 nm MCM-41 (fct-FePt NPs@MCM-41).We controlled the Pt-shell thickness of the fct-FePt NPs by treating the fct-FePt NPs@MCM-41 with acetic acid (HOAc) or hydrochloric acid (HC1) under sonication,thereby etching the surface Fe atoms of the NPs.The fct-FePt NPs deposited onto the carbon support (fct-FePt NP/C) were prepared by mixing the fct-FePt NPs@MCM-41 with carbon and subsequently removing the MCM-41 using NaOH.We also developed a facile method to synthesize acid-treated fct-FePt NP/C by using a HF solution for simultaneous surface-Fe etching and MCM-41 removal.We studied the effects of both surface-Fe etching and Pt-shell thickness on the electrocatalytic properties of fct-FePt NPs for the methanol oxidation reaction (MOR).Compared with the non-treated fct-FePt NP/C catalyst,the HOAc-treated and HCl-treated catalysts exhibit up to 34% larger electrochemically active surface areas (ECASAs);in addition,the HCl-treated fct-FePt NP (with ~1.0 nm Pt shell)/C catalyst exhibits the highest specific activity.The HF-treated fct-FePt NP/C exhibits an ECASA almost 2 times larger than those of the other acid-treated fct-FePt NP/C catalysts and shows the highest mass activity (1,435 mA.mg~,2.3 times higher than that of the commercial Pt/C catalyst) and stability among the catalysts tested.Our findings demonstrate that the surface-Fe etching for the generation of the Pt shell on fct-FePt NPs and the Pt-shell thickness can be factors for optimizing the electrocatalysis of the MOR. 相似文献
996.
997.
998.
Biological Functions and Current Advances in Isolation and Detection Strategies for Exosome Nanovesicles
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Kseniia Boriachek Md. Nazmul Islam Andreas Möller Carlos Salomon Nam‐Trung Nguyen Md. Shahriar A. Hossain Yusuke Yamauchi Muhammad J. A. Shiddiky 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(6)
Exosomes are nanoscale (≈30–150 nm) extracellular vesicles of endocytic origin that are shed by most types of cells and circulate in bodily fluids. Exosomes carry a specific composition of proteins, lipids, RNA, and DNA and can work as cargo to transfer this information to recipient cells. Recent studies on exosomes have shown that they play an important role in various biological processes, such as intercellular signaling, coagulation, inflammation, and cellular homeostasis. These functional roles are attributed to their ability to transfer RNA, proteins, enzymes, and lipids, thereby affecting the physiological and pathological conditions in various diseases, including cancer and neurodegenerative, infectious, and autoimmune diseases (e.g., cancer initiation, progression, and metastasis). Due to these unique characteristics, exosomes are considered promising biomarkers for the diagnosis and prognosis of various diseases via noninvasive or minimally invasive procedures. Over the last decade, a plethora of methodologies have been developed for analyzing disease‐specific exosomes using optical and nonoptical tools. Here, the major biological functions, significance, and potential role of exosomes as biomarkers and therapeutics are discussed. Furthermore, an overview of the most commonly used techniques for exosome analysis, highlighting the major technical challenges and limitations of existing techniques, is presented. 相似文献
999.
Euijung Yang Hyeong‐Joon Ahn Nam‐Hyo Kim Hee‐Seok Jung Kyoung‐Rock Kim Wonil Hwang 《人机工程学与制造业中的人性因素》2015,25(5):573-584
Driver and passengers recognize the interior spaces of cars psychologically as well as physically. Since the car companies have difficulty extending the physical spaces of cars due to the cost and physical constraints, they tend to make an effort to widen the perceived space instead of the physical space. In this study, we aim to investigate the effectiveness of car interior designs to which optical illusions are applied to increase their perceived roominess. Instrument panels, door‐trim armrests, and A‐pillars were chosen as the interior spaces of cars that optical illusions were applied to because drivers most frequently recognize and use them. To get alternative car interior designs, the original car designs were modified by applying optical illusions. Also, the questionnaire that includes 28 questions was used to measure “perceived roominess,” “space completeness,” “openness,” “dullness,” and “narrowness” for original interior design and alternative designs based on optical illusions, and 30 people participated in the experiments that were conducted to compare among original and optical illusion–based designs. As a result, optical illusion–based designs were significantly better than original designs in terms of perceived roominess, and the following alternative designs were recommended: the instrument panel design of a 30% longer converging point than the original design, the horizontal door‐trim armrest design, and the A‐pillar design whose cross section is rectangular. We can conclude that the optical illusions can be applied to designing in‐vehicle spaces to increase perceived roominess. 相似文献
1000.
Do Hyung Park Han Wool Park Jong Won Chung Kyungah Nam Shinyoung Choi Yoon Sun Chung Haejung Hwang BongSoo Kim Do Hwan Kim 《Advanced functional materials》2019,29(18)
Highly stretchable, high‐mobility, and free‐standing coplanar‐type all‐organic transistors based on deformable solid‐state elastomer electrolytes are demonstrated using ionic thermoplastic polyurethane (i‐TPU), thereby showing high reliability under mechanical stimuli as well as low‐voltage operation. Unlike conventional ionic dielectrics, the i‐TPU electrolyte prepared herein has remarkable characteristics, i.e., a large specific capacitance of 5.5 µF cm?2, despite the low weight ratio (20 wt%) of the ionic liquid, high transparency, and even stretchability. These i‐TPU‐based organic transistors exhibit a mobility as high as 7.9 cm2 V?1 s?1, high bendability (Rc, radius of curvature: 7.2 mm), and good stretchability (60% tensile strain). Moreover, they are suitable for low‐voltage operation (VDS = ?1.0 V, VGS = ?2.5 V). In addition, the electrical characteristics such as mobility, on‐current, and threshold voltage are maintained even in the concave and convex bending state (bending tensile strain of ≈3.4%), respectively. Finally, free‐standing, fully stretchable, and semi‐transparent coplanar‐type all‐organic transistors can be fabricated by introducing a poly(3,4‐ethylenedioxythiophene):polystyrene sulfonic acid layer as source/drain and gate electrodes, thus achieving low‐voltage operation (VDS = ?1.5 V, VGS = ?2.5 V) and an even higher mobility of up to 17.8 cm2 V?1 s?1. Moreover, these devices withstand stretching up to 80% tensile strain. 相似文献