全文获取类型
收费全文 | 2500篇 |
免费 | 134篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 25篇 |
综合类 | 2篇 |
化学工业 | 631篇 |
金属工艺 | 41篇 |
机械仪表 | 56篇 |
建筑科学 | 73篇 |
矿业工程 | 2篇 |
能源动力 | 103篇 |
轻工业 | 170篇 |
水利工程 | 8篇 |
石油天然气 | 4篇 |
无线电 | 286篇 |
一般工业技术 | 489篇 |
冶金工业 | 133篇 |
原子能技术 | 11篇 |
自动化技术 | 601篇 |
出版年
2024年 | 2篇 |
2023年 | 30篇 |
2022年 | 43篇 |
2021年 | 66篇 |
2020年 | 63篇 |
2019年 | 53篇 |
2018年 | 74篇 |
2017年 | 62篇 |
2016年 | 90篇 |
2015年 | 63篇 |
2014年 | 103篇 |
2013年 | 184篇 |
2012年 | 186篇 |
2011年 | 229篇 |
2010年 | 177篇 |
2009年 | 147篇 |
2008年 | 148篇 |
2007年 | 151篇 |
2006年 | 107篇 |
2005年 | 88篇 |
2004年 | 68篇 |
2003年 | 50篇 |
2002年 | 54篇 |
2001年 | 49篇 |
2000年 | 34篇 |
1999年 | 40篇 |
1998年 | 58篇 |
1997年 | 42篇 |
1996年 | 20篇 |
1995年 | 18篇 |
1994年 | 20篇 |
1993年 | 18篇 |
1992年 | 20篇 |
1991年 | 10篇 |
1990年 | 12篇 |
1989年 | 6篇 |
1988年 | 4篇 |
1987年 | 9篇 |
1986年 | 6篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1978年 | 2篇 |
1977年 | 4篇 |
1976年 | 3篇 |
1970年 | 1篇 |
1962年 | 1篇 |
1960年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有2635条查询结果,搜索用时 15 毫秒
991.
Youchao Wang Dr. Patrick S. Felder Dr. Pierre Mesdom Dr. Olivier Blacque Prof. Dr. Thomas L. Mindt Dr. Kevin Cariou Prof. Dr. Gilles Gasser 《Chembiochem : a European journal of chemical biology》2023,24(19):e202300467
The search for new metal-based photosensitizers (PSs) for anticancer photodynamic therapy (PDT) is a fast-developing field of research. Knowing that polymetallic complexes bear a high potential as PDT PSs, in this study, we aimed at combining the known photophysical properties of a rhenium(I) tricarbonyl complex and a ruthenium(II) polypyridyl complex to prepare a ruthenium-rhenium binuclear complex that could act as a PS for anticancer PDT. Herein, we present the synthesis and characterization of such a system and discuss its stability in aqueous solution. In addition, one of our complexes prepared, which localized in mitochondria, was found to have some degree of selectivity towards two types of cancerous cells: human lung carcinoma A549 and human colon colorectal adenocarcinoma HT29, with interesting photo-index (PI) values of 135.1 and 256.4, respectively, compared to noncancerous retinal pigment epithelium RPE1 cells (22.4). 相似文献
992.
Diego L. Brítez Michael B. Prime Sana Werda Raynald Laheurte Philippe Darnis Olivier Cahuc 《Strain》2023,59(1):e12430
Many destructive methods for measuring residual stresses such as the slitting method require an inverse analysis to solve the problem. The accuracy of the result as well as an uncertainty component (the model uncertainty) depends on the basis functions used in the inverse solution. The use of a series expansion as the basis functions for the inverse solution was analysed in a previous work for the particular case where functions orders grew consecutively. The present work presents a new estimation of the model uncertainty and a new improved methodology to select the final basis functions for the case where the basis is composed of polynomials. Including nonconsecutive polynomial orders in the basis generates a larger space of possible solutions to be evaluated and allows the possibility to include higher-order polynomials. The paper includes a comparison with two other inverse analyses methodologies applied to synthetically generated data. With the new methodology, the final error is reduced and the uncertainty estimation improved. 相似文献
993.
Jeannine Grüne Giacomo Londi Alexander J. Gillett Basil Stähly Sebastian Lulei Maria Kotova Yoann Olivier Vladimir Dyakonov Andreas Sperlich 《Advanced functional materials》2023,33(12):2212640
The great progress in organic photovoltaics (OPV) over the past few years has been largely achieved by the development of non-fullerene acceptors (NFAs), with power conversion efficiencies now approaching 20%. To further improve device performance, loss mechanisms must be identified and minimized. Triplet states are known to adversely affect device performance, since they can form energetically trapped excitons on low-lying states that are responsible for non-radiative losses or even device degradation. Halogenation of OPV materials has long been employed to tailor energy levels and to enhance open circuit voltage. Yet, the influence on recombination to triplet excitons has been largely unexplored. Using the complementary spin-sensitive methods of photoluminescence detected magnetic resonance and transient electron paramagnetic resonance corroborated by transient absorption and quantum-chemical calculations, exciton pathways in OPV blends are unravelled employing the polymer donors PBDB-T, PM6, and PM7 together with NFAs Y6 and Y7. All blends reveal triplet excitons on the NFA populated via non-geminate hole back transfer and, in blends with halogenated donors, also by spin-orbit coupling driven intersystem crossing. Identifying these triplet formation pathways in all tested solar cell absorber films highlights the untapped potential for improved charge generation to further increase plateauing OPV efficiencies. 相似文献
994.
Narayanaswamy Kamatham Olzhas A. Ibraikulov Pablo Durand Jing Wang Olivier Boyron Benoît Heinrich Thomas Heiser Patrick Lévêque Nicolas Leclerc Stéphane Méry 《Advanced functional materials》2021,31(6):2007734
Herein reported is the impact of the functionalization of four different semiconducting polymer structures by a linear siloxane-terminated side-chains. The latter is tetrasiloxane (Si4) or trisiloxane (Si3) chains, substituted at their extremity to a pentylene linker. The polymer structure is based on 5,6-difluorobenzothiadiazole comonomer (PF2), a diketopyrrolopyrrole unit (PDPP-TT), a naphtalediimide unit (PNDI-T2), and a poly[bis(thiophen-2-yl)thieno[3,2,b]thiophene (PBTTT). The properties of these siloxane-functionalized polymers are scrutinized and compared with the ones of their alkyl-substituted polymer analogues. The impact of the alkyl-to-siloxane chain substitution clearly depends on the molecular section of the side chains. When a branched 2-octyldodecyl chain (C20) is replaced by a Si4 chain of same molecular section, the greatest impact is the strong increase of the π-stacking overlap of the polymer backbones. This effect leads to a significative enhancement of the charge mobility values of the polymers. As in-plane and out-of-plane mobility are increased simultaneously, this π-overlap enhancement effect happens to be preponderant over the polymer orientation variations. When a linear tetradecyl chain (C14) is replaced by a linear Si3 chain of twice larger molecular section, the polymer structure is profoundly affected. While PBTTT-C14 is crystalline and purely edge-on, PBTTT-Si3 is mesomorphic and shows a mixed face-on/edge-on orientation. 相似文献
995.
Anna K. Puszko Piotr Sosnowski Rachel Rignault-Bricard Olivier Hermine Grard Hopfgartner Karolina Puka-Ziach Yves Lepelletier Aleksandra Misicka 《International journal of molecular sciences》2021,22(1)
Neuropilin-1 (NRP-1), the major co-receptor of vascular endothelial growth factor receptor-2 (VEGFR-2), may also independently act with VEGF-A165 to stimulate tumour growth and metastasis. Therefore, there is great interest in compounds that can block VEGF-A165/NRP-1 interaction. Peptidomimetic type inhibitors represent a promising strategy in the treatment of NRP-1-related disorders. Here, we present the synthesis, affinity, enzymatic stability, molecular modeling and in vitro binding evaluation of the branched urea–peptide hybrids, based on our previously reported Lys(hArg)-Dab-Oic-Arg active sequence, where the Lys(hArg) branching has been modified by introducing urea units to replace the peptide bond at various positions. One of the resulting hybrids increased the affinity of the compound for NRP-1 more than 10-fold, while simultaneously improving resistance for proteolytic stability in serum. In addition, ligand binding to NRP-1 induced rapid protein stock exocytotic trafficking to the plasma membrane in breast cancer cells. Examined properties characterize this compound as a good candidate for further development of VEGF165/NRP-1 inhibitors. 相似文献
996.
Eva Ogire Olivier Diaz Pierre-Olivier Vidalain Vincent Lotteau Philippe Desprs Marjolaine Roche 《International journal of molecular sciences》2021,22(4)
La Reunion island in the South West Indian Ocean is now endemic for dengue following the introduction of dengue virus serotype 2 (DENV-2) cosmopolitan-I genotype in 2017. DENV-2 infection causes a wide spectrum of clinical manifestations ranging from flu-like disease to severe dengue. The nonstructural glycoprotein 1 (NS1) has been identified as playing a key role in dengue disease severity. The intracellular NS1 exists as a homodimer, whereas a fraction is driven towards the plasma membrane or released as a soluble hexameric protein. Here, we characterized the NS1 glycoproteins from clinical isolates DES-14 and RUN-18 that were collected during the DENV-2 epidemics in Tanzania in 2014 and La Reunion island in 2018, respectively. In relation to hepatotropism of the DENV, expression of recombinant DES-14 NS1 and RUN-18 NS1 glycoproteins was compared in human hepatoma Huh7 cells. We observed that RUN-18 NS1 was poorly stable in Huh7 cells compared to DES-14 NS1. The instability of RUN-18 NS1 leading to a low level of NS1 secretion mostly relates to lysine residues on positions 272 and 324. Our data raise the issue of the consequences of a defect in NS1 stability in human hepatocytes in relation to the major role of NS1 in the pathogenesis of the DENV-2 infection. 相似文献
997.
Nicolas Barnich Michael Rodrigues Pierre Sauvanet Caroline Chevarin Sylvain Denis Olivier Le Goff Danielle Faure-Imbert Thierry Hanh Christian F Roques Benoit Chassaing Monique Alric 《International journal of molecular sciences》2021,22(9)
Natural mineral water (NMWs) intake has been traditionally used in the treatment of various gastrointestinal diseases. We investigated the effect of two French NMWs, one a calcium and magnesium sulphate, sodium chloride, carbonic, and ferruginous water (NMW1), the other a mainly bicarbonate water (NMW2) on the prevention of intestinal inflammation. Intestinal epithelial cells stimulated with heat inactivated Escherichia coli or H2O2 were treated with NMWs to evaluate the anti-inflammatory effects. Moderate colitis was induced by 1% dextran sulfate sodium (DSS) in Balbc/J mice drinking NMW1, NWW2, or control water. General signs and histological features of colitis, fecal lipocalin-2 and pro-inflammatory KC cytokine levels, global mucosa-associated microbiota, were analyzed. We demonstrated that both NMW1 and NMW2 exhibited anti-inflammatory effects using intestinal cells. In induced-colitis mice, NMW1 was effective in dampening intestinal inflammation, with significant reductions in disease activity scores, fecal lipocalin-2 levels, pro-inflammatory KC cytokine release, and intestinal epithelial lesion sizes. Moreover, NMW1 was sufficient to prevent alterations in the mucosa-associated microbiota. These observations, through mechanisms involving modulation of the mucosa-associated microbiota, emphasize the need of investigation of the potential clinical efficiency of such NMWs to contribute, in human beings, to a state of low inflammation in inflammatory bowel disease. 相似文献
998.
Julie-Anne Fenger Gregory T. Sigurdson Rebecca J. Robbins Thomas M. Collins M. Mnica Giusti Olivier Dangles 《International journal of molecular sciences》2021,22(9)
Red cabbage (RC) and purple sweet potato (PSP) are naturally rich in acylated cyanidin glycosides that can bind metal ions and develop intramolecular π-stacking interactions between the cyanidin chromophore and the phenolic acyl residues. In this work, a large set of RC and PSP anthocyanins was investigated for its coloring properties in the presence of iron and aluminum ions. Although relatively modest, the structural differences between RC and PSP anthocyanins, i.e., the acylation site at the external glucose of the sophorosyl moiety (C2-OH for RC vs. C6-OH for PSP) and the presence of coordinating acyl groups (caffeoyl) in PSP anthocyanins only, made a large difference in the color expressed by their metal complexes. For instance, the Al3+-induced bathochromic shifts for RC anthocyanins reached ca. 50 nm at pH 6 and pH 7, vs. at best ca. 20 nm for PSP anthocyanins. With Fe2+ (quickly oxidized to Fe3+ in the complexes), the bathochromic shifts for RC anthocyanins were higher, i.e., up to ca. 90 nm at pH 7 and 110 nm at pH 5.7. A kinetic analysis at different metal/ligand molar ratios combined with an investigation by high-resolution mass spectrometry suggested the formation of metal–anthocyanin complexes of 1:1, 1:2, and 1:3 stoichiometries. Contrary to predictions based on steric hindrance, acylation by noncoordinating acyl residues favored metal binding and resulted in complexes having much higher molar absorption coefficients. Moreover, the competition between metal binding and water addition to the free ligands (leading to colorless forms) was less severe, although very dependent on the acylation site(s). Overall, anthocyanins from purple sweet potato, and even more from red cabbage, have a strong potential for development as food colorants expressing red to blue hues depending on pH and metal ion. 相似文献
999.
Wenjuan Wei Claire Dassonville Sutharsini Sivanantham Anthony Gregoire Fabien Mercier Barbara Le Bot Laeticia Malingre Olivier Ramalho Mickaël Derbez Corinne Mandin 《Indoor air》2021,31(1):156-169
The indoor environmental quality in classrooms can largely affect children's daily exposure to indoor chemicals in schools. To date, there has not been a comprehensive study of the concentrations of semivolatile organic compounds (SVOCs) in French schools. Therefore, the French Observatory for Indoor Air Quality (OQAI) performed a field study of SVOCs in 308 nurseries and elementary schools between June 2013 and June 2017. The concentrations of 52 SVOCs, including phthalates, polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), synthetic musks, and pesticides, were measured in air and settled dust (40 SVOCs in both air and dust, 12 in either air or dust). The results showed that phthalates had the highest concentrations among the SVOCs in both the air and dust. Other SVOCs, including tributyl phosphate, fluorene, phenanthrene, gamma-hexachlorocyclohexane (gamma-HCH, lindane), galaxolide, and tonalide, also showed high concentrations in both the air and dust. Theoretical equations were developed to estimate the SVOC partitioning between the air and settled dust from either the octanol/air partition coefficient or the boiling point of the SVOCs. The regression constants of the equations were determined using the data set of the present study for phthalates and PAHs. 相似文献
1000.
Fanlin Zeng Jürgen Malzbender Stefan Baumann Wenyu Zhou Mirko Ziegner Arian Nijmeijer Olivier Guillon Ruth Schwaiger Wilhelm Albert Meulenberg 《Journal of the American Ceramic Society》2021,104(4):1814-1830
Ce0.8Gd0.2O2−δ-FeCo2O4 composites are attractive candidate materials for high-purity oxygen generation providing robust chemical stability. Aiming for future industrial applications, a feasible solid-state reaction process with one thermal processing step was used to synthesize 50 wt% Ce0.8Gd0.2O2−δ:50 wt% FeCo2O4 and 85 wt% Ce0.8Gd0.2O2−δ:15 wt% FeCo2O4 composites. Mechanical reliabilities of the sintered membranes were assessed based on the characterized mechanical properties and subcritical crack growth behavior. In general, the fracture strengths of as-sintered membranes were reduced by tensile residual stresses and microcracks. In particular, the enhanced subcritical crack growth behavior, which leads to limited stress tolerance and high failure probability after a 10-year operation, was evaluated in more detail. Further materials and processing improvements are needed to eliminate the tensile stress and microcracks to warrant a long-term reliable operation of the composites. 相似文献