全文获取类型
收费全文 | 424篇 |
免费 | 41篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 2篇 |
综合类 | 1篇 |
化学工业 | 113篇 |
金属工艺 | 2篇 |
机械仪表 | 15篇 |
建筑科学 | 12篇 |
能源动力 | 15篇 |
轻工业 | 23篇 |
水利工程 | 11篇 |
无线电 | 55篇 |
一般工业技术 | 92篇 |
冶金工业 | 50篇 |
原子能技术 | 12篇 |
自动化技术 | 66篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 9篇 |
2021年 | 16篇 |
2020年 | 4篇 |
2019年 | 10篇 |
2018年 | 15篇 |
2017年 | 30篇 |
2016年 | 19篇 |
2015年 | 15篇 |
2014年 | 17篇 |
2013年 | 20篇 |
2012年 | 27篇 |
2011年 | 37篇 |
2010年 | 18篇 |
2009年 | 24篇 |
2008年 | 18篇 |
2007年 | 16篇 |
2006年 | 14篇 |
2005年 | 16篇 |
2004年 | 11篇 |
2003年 | 8篇 |
2002年 | 10篇 |
2001年 | 8篇 |
2000年 | 9篇 |
1999年 | 12篇 |
1998年 | 13篇 |
1997年 | 15篇 |
1996年 | 14篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1988年 | 2篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1973年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有469条查询结果,搜索用时 15 毫秒
21.
Ha Nee Jang Jin Hyun Kim Myeong Hee Jung Taekil Tak Jung Hwa Jung Seunghye Lee Sehyun Jung Se-Ho Chang Hyun-Jung Kim 《International journal of molecular sciences》2022,23(3)
Ischemia-reperfusion injury (IRI) is a major cause of acute kidney injury (AKI) and progression to chronic kidney disease (CKD). However, no effective therapeutic intervention has been established for ischemic AKI. Endothelial progenitor cells (EPCs) have major roles in the maintenance of vascular integrity and the repair of endothelial damage; they also serve as therapeutic agents in various kidney diseases. Thus, we examined whether EPCs have a renoprotective effect in an IRI mouse model. Mice were assigned to sham, EPC, IRI-only, and EPC-treated IRI groups. EPCs originating from human peripheral blood were cultured. The EPCs were administered 5 min before reperfusion, and all mice were killed 72 h after IRI. Blood urea nitrogen, serum creatinine, and tissue injury were significantly increased in IRI mice; EPCs significantly improved the manifestations of IRI. Apoptotic cell death and oxidative stress were significantly reduced in EPC-treated IRI mice. Administration of EPCs decreased the expression levels of NLRP3, cleaved caspase-1, p-NF-κB, and p-p38. Furthermore, the expression levels of F4/80, ICAM-1, RORγt, and IL-17RA were significantly reduced in EPC-treated IRI mice. Finally, the levels of EMT-associated factors (TGF-β, α-SMA, Snail, and Twist) were significantly reduced in EPC-treated IRI mice. This study shows that inflammasome-mediated inflammation accompanied by immune modulation and fibrosis is a potential target of EPCs as a treatment for IRI-induced AKI and the prevention of progression to CKD. 相似文献
22.
Ultrasonic Chemistry: Carbon–Heteroatom Bond Formation by an Ultrasonic Chemical Reaction for Energy Storage Systems (Adv. Mater. 47/2017) 下载免费PDF全文
23.
Kwang Su Kim Jong Uk Kim Sori Lee Ju Seung Lee Young Jin Jo Byeonghak Park Hyowon Tak Pil J. Yoo Tae‐il Kim 《Advanced functional materials》2017,27(38)
Nanofabrication is an indispensable process in nanoscience and nanotechnology. Unconventional lithographic techniques are often used for fabrication as alternatives to photolithography because they are faster, more cost‐effective, and simpler to use. However, these techniques are limited in scalability and utility because of the collapse of preprinted structures during step‐and‐repeat processes. This study proposes a new class of temperature‐controllable polymeric molds that are coated with a metal such that any site‐specific patterning can be accomplished in a programmable manner using selective contact‐dewetting lithography. The lithography allows sub‐100 nm patterning, step‐and‐repeat processing, and hierarchical structure fabrication. The programmable feature of the lithography can be utilized for the structural coloring and shaping of objects. Large‐area programmable patterning, semiconductor device manufacturing, and the fabrication of iridescent security devices would benefit from the unique features of the proposed strategy. 相似文献
24.
Arijit Lodh Ujjal Tewary Ram Pratap Singh Tawqeer Nasir Tak Aditya Prakash Alankar Alankar P. J. Guruprasad Indradev Samajdar 《Metallurgical and Materials Transactions A》2018,49(12):5946-5952
Orientation-dependent developments in misorientation and residual stress, in rolled aluminum, were quantified experimentally and simulated numerically. The latter involved analysis using a crystal plasticity finite element model, accounting for anisotropies in slip system hardening but neglecting near-neighbor interactions, and discrete dislocation dynamics of the single crystals. Both were successful in capturing the experimental patterns of orientation dependence. Numerical simulations, without slip transfer across the neighboring grains, thus established the defining role of dislocation interactions in establishing orientation-sensitive microstructural evolution. 相似文献
25.
Distrust hinders disputing parties and mediators from achieving mediation success. Mediators therefore often use different trust-building tactics to generate some degree of trust in themselves and in the mediation process. This paper reports a study that identified the trust-building tactics used by construction mediators and examined the efficacy of these tactics with respect to their outcomes. Three study stages were designed. With reference to the mediation model of Sloan (1998), trust-building tactics and outcomes were first identified in Stage I. Next, the data were collected from accredited mediators with a questionnaire survey in Stage II. The collected data were then validated via reliability assessments in Stage III. With the use of multiple regression analyses, the efficacy of the trust-building tactics was examined by relating these tactics to their outcomes. The findings of this study suggest that the trust-building tactics used in Step 4 (i.e., explore interests) of Sloan’s (1998) mediation model are influential in developing trust among disputing parties and that they can also act as a time-saving tool in the mediation process. Furthermore, it was found that mediators can earn trust by adopting the trust-building tactics used in Step 3 (i.e., issues and trust) of Sloan’s (1998) model. These tactics can also serve to improve the relationships between the disputing parties. The results show that the trust-building tactics used in the final step (i.e., solutions) of Sloan’s (1998) model seem to have low efficacy in developing trust among disputing parties. 相似文献
26.
Feng-Jin Li Byeong-Gyu Roh Hyun-Taek Lim Ji-Soo Kim Jae-Yong Park Hong-Woo Yu Seung-Chul Park Yoon-Heung Tak Byung-Chul Ahn 《Thin solid films》2009,517(9):2941-2944
Thin silver film is widely used as the cathode in organic light-emitting diode displays and it is generally fabricated using the thermal evaporation method. But during the evaporation process, there is an inevitable outgassing problem and this creates high viscosity bubbles in melted silver. When the bubbles break, the high energy released scatters silver droplets which damage the silver surface. In this study, we were able to decrease the number of droplets from 6,171 to 278 with a degassing process of 400 °C for 6 h before proceeding with a thermal evaporation process. 相似文献
27.
To improve the input-output coupling loss of a vertically coupled microring resonator filter, we fabricated microring resonators on an antiresonant reflecting optical waveguide (ARROW) with a large spot size and on the rectangular busline waveguide with a spot-size transformer. The spot size and the tapered structure were optimally designed from the viewpoint of spot-size matching to single-mode fibers and the reduction of radiation loss. Clear dropping responses were demonstrated for the ARROW-based microring resonator filters, and the coupling loss was successfully reduced by 22 dB. 相似文献
28.
29.
ac losses have been investigated experimentally as well as theoretically in tapes having on the surface several normal conducting and/or superconducting layers. The superconducting layers under investigation have been Nb3Sn on a niobium substrate and Nb3Ge on a stainless steel substrate. It has been proved that the layered structure of the tapes is well reflected by the stepwise character of the ac losses dependence on the amplitude of the surface magnetic field. The magnetic flux passing through a surperconducting layer or surface barrier into the inside of the tape enhances the losses in the passed barrier or layer. 相似文献
30.
In this paper, the problem of robust discretisation of linear time-invariant (LTI) systems with polytopic uncertainties is introduced. More specifically, the main objective is to provide a systematic way to find an approximate discrete-time (DT) model of a continuous-time (CT) plant with uncertainties in polytopic domain. The system matrices of polytopic DT model to be found are expressed as parameter-dependent matrices which are homogeneous polynomials of arbitrary degree with respect to the uncertain variables in the simplex, and is obtained in such a way that the norm between the system matrices and the truncated power series of the exact DT model is minimised while preserving the polytopic structure of the original CT plant. The solution procedures proposed are presented in terms of single-parameter minimisation problems subject to linear matrix inequality (LMI) constraints which are numerically tractable via LMI solvers. Finally, examples are given to show the validity and effectiveness of the proposed techniques. 相似文献