全文获取类型
收费全文 | 387篇 |
免费 | 27篇 |
专业分类
电工技术 | 4篇 |
化学工业 | 122篇 |
金属工艺 | 9篇 |
机械仪表 | 7篇 |
建筑科学 | 15篇 |
能源动力 | 9篇 |
轻工业 | 62篇 |
水利工程 | 5篇 |
石油天然气 | 2篇 |
无线电 | 20篇 |
一般工业技术 | 49篇 |
冶金工业 | 75篇 |
原子能技术 | 1篇 |
自动化技术 | 34篇 |
出版年
2023年 | 4篇 |
2022年 | 12篇 |
2021年 | 23篇 |
2020年 | 8篇 |
2019年 | 12篇 |
2018年 | 6篇 |
2017年 | 18篇 |
2016年 | 11篇 |
2015年 | 11篇 |
2014年 | 18篇 |
2013年 | 29篇 |
2012年 | 15篇 |
2011年 | 32篇 |
2010年 | 16篇 |
2009年 | 16篇 |
2008年 | 23篇 |
2007年 | 20篇 |
2006年 | 13篇 |
2005年 | 11篇 |
2004年 | 10篇 |
2003年 | 12篇 |
2002年 | 6篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 6篇 |
1998年 | 2篇 |
1997年 | 6篇 |
1996年 | 2篇 |
1995年 | 6篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 5篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1986年 | 5篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1980年 | 2篇 |
1978年 | 3篇 |
1975年 | 2篇 |
1961年 | 2篇 |
1957年 | 1篇 |
1955年 | 1篇 |
1954年 | 1篇 |
1953年 | 1篇 |
1952年 | 1篇 |
1949年 | 1篇 |
1920年 | 1篇 |
排序方式: 共有414条查询结果,搜索用时 15 毫秒
401.
Andrei Rogalev José Goulon Gérard Goujon Fabrice Wilhelm Isamu Ogawa Toshitaka Idehara 《Journal of Infrared, Millimeter and Terahertz Waves》2012,33(7):777-793
X-ray Detected Magnetic Resonance (XDMR) is a novel spectroscopy which makes use of X-ray Magnetic Circular Dichroism (XMCD) to probe the resonant precession of local magnetization components in a strong microwave pump field. In Sections?1 and 2, we briefly review the conceptual bases of XDMR and the potential interest of increasing the pumping frequency up to the THz frequency range. In Sections?3–5, we discuss the feasibility of such challenging experiments. Starting from a comparison of experiments carried out either in the transverse (TRD) or longitudinal (LOD) detection geometries, we show that XDMR measurements at sub-THz frequencies require a substantial increase in pumping power: this is where a gyrotron source looks most appropriate. It is the aim of this paper to discuss how to conduct such experiments, emphasis being laid on feasibility tests recently carried out at the ESRF using a refurbished version of Gyrotron FU-II built at the FIR-FU. In this context, we propose a new detection scheme of sub-THz XDMR spectra based on the concept of frequency-mixing in LOD geometry. 相似文献
402.
Funda Inceoglu Julien Ville Nessim Ghamri Jean Laurent Pradel Audrey Durin Rudy Valette Bruno Vergnes 《Polymer Composites》2011,32(11):1842-1850
The inter‐relationship between processing conditions and fiber breakage has been studied for glass fiber‐reinforcedpolyamide 12, prepared using (i) an internal batch mixer, (ii) a laboratory scale corotating twin screw extruder, and (iii) an industrial scale twin screw extruder. The average fiber lengths and fiber length distributions were measured for various compounding conditions (screw or rotor speed, mixing time, feed rate). Experimental results have shown that fiber breakage depends on both screw speed and mixing time, the later being controlled, in an extruder, by the feed rate. For a given compounding system (batch mixer or twin screw extruder), the energy input (specific mechanical energy, SME) during the compounding process is found to be a reliable parameter, which governs fiber length (average, minimal, and maximal) evolution. Experimental data are correctly described with a model defining change in fiber length as a function of SME. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers 相似文献
403.
404.
Fanuel A. Demas Ahmed Hassanali Esther N. Mwangi Edna C. Kunjeku Audrey R. Mabveni 《Journal of chemical ecology》2000,26(4):1079-1093
The response of mated naive Ixodiphagus hookeri females to cattle and Amblyomma variegatum nymphal odors was tested in a Y-tube olfactometer. I. hookeri females were attracted to cattle urine, dung, and odors from tick-free feeding sites of A. variegatum nymphs on cattle, e.g., dewlaps, front heels, and hind heels. Tick-free scrotal odors did not attract the parasitoids. Furthermore, odors from off-host unfed and fed A. variegatum nymphs did not attract the parasitoids, despite an increase in the number of the nymphs to amplify any odor signal. A blend of odors from feeding on-host nymphs and cattle scrota attracted the parasitoids. In T-tube bioassays, I. hookeri females were attracted to hexane washes and fecal extracts of A. variegatum nymphs. 相似文献
405.
Elodie Hedou Sara Douceau Arnaud Chevilley Alexandre Varangot Audrey M. Thiebaut Hortense Triniac Isabelle Bardou Carine Ali Mike Maillasson Tiziana Crepaldi Paolo Comoglio Eloïse Lemarchand Vronique Agin Benoit D. Roussel Denis Vivien 《International journal of molecular sciences》2021,22(24)
Tissue-type plasminogen activator (tPA) plays roles in the development and the plasticity of the nervous system. Here, we demonstrate in neurons, that by opposition to the single chain form (sc-tPA), the two-chains form of tPA (tc-tPA) activates the MET receptor, leading to the recruitment of N-Methyl-d-Aspartate receptors (NMDARs) and to the endocytosis and proteasome-dependent degradation of NMDARs containing the GluN2B subunit. Accordingly, tc-tPA down-regulated GluN2B-NMDAR-driven signalling, a process prevented by blockers of HGFR/MET and mimicked by its agonists, leading to a modulation of neuronal death. Thus, our present study unmasks a new mechanism of action of tPA, with its two-chains form mediating a crosstalk between MET and the GluN2B subunit of NMDARs to control neuronal survival. 相似文献
406.
Nazarian Arbi; Rodarte-Freeman Audrey L.; McDougall Sanders A. 《Canadian Metallurgical Quarterly》1999,113(4):816
The purpose of this study was to determine whether dopamine (DA) systems modulate kappa opioid-mediated ultrasonic vocalizations (USVs), antinociception, and locomotion in young rats. Seventeen-day-old rats were injected with the kappa agonist U-50,488 (0.0-7.5 mg/kg) and saline, the D?-like receptor agonist R(-)-propylnorapomorphine (NPA; 0. 1 or 1.0 mg/kg), the indirect DA agonist cocaine (10 or 20 mg/kg), or the DA antagonist flupenthixol (0.25 or 0.5 mg/kg). USVs and locomotion were measured for 6 min, with antinociception being assessed with a tail-flick test. Kappa receptor stimulation produced analgesia and increased USVs and locomotion. U-50,488-induced analgesia was potentiated by NPA, whereas U-50,488-induced USVs were attenuated by both DA agonists. NPA and flupenthixol depressed U-50,488's locomotor effects. These results show that DA systems interact with kappa opioid systems to modulate USVs, antinociception, and locomotion in preweanling rats. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
407.
Audrey Biloon 《International Journal of Network Management》1999,9(4):209-211
A standard contract (one printed on a standard form, with standard language) can be changed or fully rewritten to meet your company's specific needs. Buying equipment without a contract that meets your company's specific needs and that is drafted or reviewed by legal counsel (specifically a lawyer who knows your company's needs well) is the equivalent of buying a potential lawsuit. Prevention of problems with a good contract and legal help is your company's best insurance against waste and/or litigation. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
408.
Lisa Schlicher Paulina Kulig Audrey von Münchow Mark J. Murphy Marcel P. Keller 《International journal of molecular sciences》2022,23(3)
Cenerimod is a potent, selective sphingosine 1-phosphate receptor 1 (S1P1) modulator currently investigated in a Phase IIb study in patients with systemic lupus erythematosus (SLE) (). S1P1 receptor modulators sequester circulating lymphocytes within lymph nodes, thereby reducing pathogenic autoimmune cells (including T and B lymphocytes) in the bloodstream and inflamed tissues, making them an effective therapeutic concept for autoimmune disorders. Although the effect of S1P receptor modulators in reducing circulating lymphocytes is well documented, the precise molecular role of the S1P1 receptor on these cell types is not fully understood. In this study, the mode of action of cenerimod on human primary lymphocytes in different activation states was investigated focusing on their chemotactic behavior towards S1P in real-time, concomitant to S1P1 receptor expression and internalization dynamics. Here, we show that cenerimod effectively prevents T and B cell migration in a concentration-dependent manner. Interestingly, while T cell activation led to strong S1P1 re-expression and enhanced migration; in B cells, an enhanced migration capacity and S1P1 receptor surface expression was observed in an unstimulated state. Importantly, concomitant treatment with glucocorticoids (GCs), a frequently used treatment for autoimmune disorders, had no impact on the inhibitory activity of cenerimod on lymphocytes. NCT03742037相似文献
409.
Synthesis and characterization of poly(2,5‐didecyl‐1,4‐phenylene vinylene), poly(2,5‐didecyloxy‐1,4‐phenylene vinylene), and their alternating copolymer
下载免费PDF全文
![点击此处可从《应用聚合物科学杂志》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Crystal A. Young Sairoong Saowsupa Audrey Hammack Andrew A. Tangonan Piched Anuragudom Huiping Jia Andrew C. Jamison Sukon Panichphant Bruce E. Gnade T. Randall Lee 《应用聚合物科学杂志》2014,131(23)
The preparation of dialkyl‐substituted poly(2,5‐didecyl‐1,4‐phenylene vinylene) ( PDDPV ) by the Horner‐Emmons polycondensation is described. Its performance in an organic light‐emitting diode (OLED) device architecture is compared with devices prepared from the analogous dialkoxy‐substituted poly(2,5‐didecyloxy‐1,4‐phenylene vinylene) ( PDOPV ) and the corresponding alkyl‐alkoxy‐substituted alternating copolymer. Additionally, the structure, stability, electrochemical, and optical properties of the PPVs were characterized by gel permeation chromatography, thermogravimetric analysis, NMR spectroscopy, cyclic voltammetry, UV‐Visible spectroscopy, and fluorescence spectroscopy. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41162. 相似文献
410.
Nitrate and nitrite concentrations were determined for sweet basil and scallions over 24 h to determine if time of sampling or harvest impacts concentrations in raw vegetables. Also, nitrate and nitrite concentrations were determined separately for various edible parts of these plants. Basil had significant changes in nitrate and nitrite concentrations over a 24 h period. Nitrate was correlated to changes in light intensity with a 3 h lag time. The highest nitrate concentrations in basil (2777 ppm) occurred around 3 h after the light intensity peaked and had low values (165–574 ppm) during the dark period. The scallion nitrate and nitrite concentrations were always low but nitrate showed a peak a few hours before sunrise. Nitrate and nitrite concentrations in some raw vegetables may be reduced by harvesting at the best time of day for each type of plant. Nitrate concentrations were different in the edible plant parts tested. 相似文献