全文获取类型
收费全文 | 3508篇 |
免费 | 200篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 66篇 |
综合类 | 1篇 |
化学工业 | 885篇 |
金属工艺 | 45篇 |
机械仪表 | 74篇 |
建筑科学 | 165篇 |
矿业工程 | 1篇 |
能源动力 | 109篇 |
轻工业 | 252篇 |
水利工程 | 11篇 |
石油天然气 | 3篇 |
武器工业 | 1篇 |
无线电 | 315篇 |
一般工业技术 | 641篇 |
冶金工业 | 243篇 |
原子能技术 | 27篇 |
自动化技术 | 873篇 |
出版年
2024年 | 5篇 |
2023年 | 42篇 |
2022年 | 138篇 |
2021年 | 157篇 |
2020年 | 78篇 |
2019年 | 90篇 |
2018年 | 99篇 |
2017年 | 97篇 |
2016年 | 148篇 |
2015年 | 118篇 |
2014年 | 148篇 |
2013年 | 235篇 |
2012年 | 214篇 |
2011年 | 239篇 |
2010年 | 202篇 |
2009年 | 202篇 |
2008年 | 186篇 |
2007年 | 177篇 |
2006年 | 124篇 |
2005年 | 103篇 |
2004年 | 128篇 |
2003年 | 101篇 |
2002年 | 71篇 |
2001年 | 59篇 |
2000年 | 54篇 |
1999年 | 42篇 |
1998年 | 65篇 |
1997年 | 55篇 |
1996年 | 59篇 |
1995年 | 36篇 |
1994年 | 33篇 |
1993年 | 25篇 |
1992年 | 22篇 |
1991年 | 13篇 |
1990年 | 7篇 |
1989年 | 14篇 |
1987年 | 13篇 |
1986年 | 6篇 |
1985年 | 15篇 |
1984年 | 21篇 |
1983年 | 10篇 |
1982年 | 8篇 |
1981年 | 8篇 |
1980年 | 3篇 |
1979年 | 6篇 |
1978年 | 4篇 |
1977年 | 10篇 |
1976年 | 7篇 |
1975年 | 3篇 |
1973年 | 4篇 |
排序方式: 共有3712条查询结果,搜索用时 15 毫秒
91.
Isabella Panfoli Daniela Calzia Silvia Ravera Paolo Bianchini Alberto Diaspro 《Microscopy research and technique》2010,73(12):1086-1090
We describe a procedure for the labeling of membranous vesicular purified subcellular fractions, to image them, typically by confocal laser scanning microscopy. Being intracellular organelles, these fractions, once purified cannot be attached to glass slides as for cells. Fractions are labeled “in batch” without prior embedding or freezing. Each labeling step performed by passages of resuspension/centrifugation is followed by washings. Then samples are dispersed on the glass slides. Mammalian retinal rod outer segment disks, intact brain stem myelin vesicles, and brain synaptosomes were chosen, as these subcellular fractions can be purified by well established procedures. These fractions were immunolabeled with specific antibodies. Moreover, by the earlier procedure, we show that the mitochondrial vital membrane potential probe MitoTracker Deep Red 633 stains myelin vesicles and rod disks before fixation, consistently with our previous reports of a respiring capacity of these membranes. Therefore, the technique seems adequate to become an instrument to study the structure and the function of these and other subcellular fractions. Microsc. Res. Tech. 73:1086–1090, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
92.
This paper presents a novel system for production of pure oxygen based on the integration of a solid oxide fuel cell (SOFC) and a solid oxide electrolyzer (SOEC). In the proposed arrangement, the SOFC provides electricity, heat and H2O in vapour phase to the SOEC which carries out the inverse reactions of the SOFC, that is the separation of H2O into H2 (used as a fuel for the SOFC) and O2 (representing the yield of the system). Simulations carried out in different operating conditions show that when the integrated SOFC–SOEC device runs at low current densities (less than 1000 A m−2), pure oxygen can be generated with an electric consumption comparable to mid-size cryogenic air separation units, and significantly lower than small scale systems based on the PSA technology. 相似文献
93.
Metal–Organic Frameworks: Biomimetic Replication of Microscopic Metal–Organic Framework Patterns Using Printed Protein Patterns (Adv. Mater. 45/2015) 下载免费PDF全文
94.
95.
96.
Gian Paolo Cimellaro Stephen Mahin Marco Domaneschi 《Computer-Aided Civil and Infrastructure Engineering》2019,34(1):3-20
Several studies on Emergency Management are available in the literature, but most of them do not consider how the human behavior during an emergency can affect the evacuation process. Therefore, the novel contribution of this article is the implementation of an agent‐based model to describe the evacuation, due to a blast in a public area, integrated with a human behavior analytical model. Each agent has its own behavior that is described in a layered framework. The first layer simulates the “agent's features” function. Then, an “individual module” describes dynamically the emotional aspects using (i) the Decision Field Theory, (ii) a stationary stochastic model, and (iii) the results coming from a questionnaire. An agent‐based model with integrated human behavior is proposed to test critical infrastructures in emergency conditions without performing full scale evacuation tests. Analyses could be performed both in real time with a hazard scenario and at the design level to predict the system response to identify the optimal configuration. Therefore, the development of the proposed methodology could support both designers and policy makers in the decision‐making process. 相似文献
97.
Giulio Destri Paolo Marenzoni 《International Journal of Circuit Theory and Applications》1996,24(3):397-407
In this paper is presented the use of the discrete-time cellular neural network (DTCNN) paradigm to develop algorithms devised for general-purpose massively parallel processing (MPP) systems. This paradigm is defined in discrete N-dimensional spaces (lattices) and is characterized by the locality of the direct information transmission between the space points (cells) and by continuous values of data and parameters; the DTCNN paradigm is thus able to express most of the typical MPP applications. A general version of a DTCNN has been implemented and optimized for three MPP architectures, namely the Connection Machines CM-2 and CM-5 and the Cray T3D. The comparison between the three machine performances with those achieved by a standard SPARC-20 workstation shows that, particularly with large lattices, the speed-up allowed in the computational times is significant and the range of solvable problem sizes is widely extended. 相似文献
98.
Parastoo Memarian Elham Pishavar Federica Zanotti Martina Trentini Francesca Camponogara Elisa Soliani Paolo Gargiulo Maurizio Isola Barbara Zavan 《International journal of molecular sciences》2022,23(3)
The successful clinical application of bone tissue engineering requires customized implants based on the receiver’s bone anatomy and defect characteristics. Three-dimensional (3D) printing in small animal orthopedics has recently emerged as a valuable approach in fabricating individualized implants for receiver-specific needs. In veterinary medicine, because of the wide range of dimensions and anatomical variances, receiver-specific diagnosis and therapy are even more critical. The ability to generate 3D anatomical models and customize orthopedic instruments, implants, and scaffolds are advantages of 3D printing in small animal orthopedics. Furthermore, this technology provides veterinary medicine with a powerful tool that improves performance, precision, and cost-effectiveness. Nonetheless, the individualized 3D-printed implants have benefited several complex orthopedic procedures in small animals, including joint replacement surgeries, critical size bone defects, tibial tuberosity advancement, patellar groove replacement, limb-sparing surgeries, and other complex orthopedic procedures. The main purpose of this review is to discuss the application of 3D printing in small animal orthopedics based on already published papers as well as the techniques and materials used to fabricate 3D-printed objects. Finally, the advantages, current limitations, and future directions of 3D printing in small animal orthopedics have been addressed. 相似文献
99.
Federico Bolognesi Nicola Fazio Filippo Boriani Viscardo Paolo Fabbri Davide Gravina Francesca Alice Pedrini Nicoletta Zini Michelina Greco Michela Paolucci Maria Carla Re Sofia Asioli Maria Pia Foschini Antonietta DErrico Nicola Baldini Claudio Marchetti 《International journal of molecular sciences》2022,23(3)
Defects of the peripheral nervous system are extremely frequent in trauma and surgeries and have high socioeconomic costs. If the direct suture of a lesion is not possible, i.e., nerve gap > 2 cm, it is necessary to use grafts. While the gold standard is the autograft, it has disadvantages related to its harvesting, with an inevitable functional deficit and further morbidity. An alternative to autografting is represented by the acellular nerve allograft (ANA), which avoids disadvantages of autograft harvesting and fresh allograft rejection. In this research, the authors intend to transfer to human nerves a novel technique, previously implemented in animal models, to decellularize nerves. The new method is based on soaking the nerve tissues in decellularizing solutions while associating ultrasounds and freeze–thaw cycles. It is performed without interrupting the sterility chain, so that the new graft may not require post-production γ-ray irradiation, which is suspected to affect the structural and functional quality of tissues. The new method is rapid, safe, and inexpensive if compared with available commercial ANAs. Histology and immunohistochemistry have been adopted to evaluate the new decellularized nerves. The study shows that the new method can be applied to human nerve samples, obtaining similar, and, sometimes better, results compared with the chosen control method, the Hudson technique. 相似文献
100.
Raffaele Raimondi Piero Zollet Francesco Paolo De Rosa Panagiotis Tsoutsanis Matteo Stravalaci Marianna Paulis Antonio Inforzato Mario R. Romano 《International journal of molecular sciences》2022,23(2)
The retinal pigmented epithelium (RPE) plays a pivotal role in retinal homeostasis. It is therefore an interesting target to fill the unmet medical need of different retinal diseases, including age-related macular degeneration and Stargardt disease. RPE replacement therapy may use different cellular sources: induced pluripotent stem cells or embryonic stem cells. Cells can be transferred as suspension on a patch with different surgical approaches. Results are promising although based on very limited samples. In this review, we summarize the current progress of RPE replacement and provide a comparative assessment of different published approaches which may become standard of care in the future. 相似文献