全文获取类型
收费全文 | 2224篇 |
免费 | 81篇 |
国内免费 | 6篇 |
专业分类
电工技术 | 18篇 |
综合类 | 2篇 |
化学工业 | 662篇 |
金属工艺 | 71篇 |
机械仪表 | 48篇 |
建筑科学 | 79篇 |
矿业工程 | 5篇 |
能源动力 | 64篇 |
轻工业 | 198篇 |
水利工程 | 11篇 |
石油天然气 | 1篇 |
无线电 | 207篇 |
一般工业技术 | 463篇 |
冶金工业 | 104篇 |
原子能技术 | 36篇 |
自动化技术 | 342篇 |
出版年
2023年 | 13篇 |
2022年 | 29篇 |
2021年 | 47篇 |
2020年 | 25篇 |
2019年 | 26篇 |
2018年 | 41篇 |
2017年 | 52篇 |
2016年 | 47篇 |
2015年 | 35篇 |
2014年 | 71篇 |
2013年 | 131篇 |
2012年 | 128篇 |
2011年 | 159篇 |
2010年 | 115篇 |
2009年 | 124篇 |
2008年 | 137篇 |
2007年 | 110篇 |
2006年 | 113篇 |
2005年 | 80篇 |
2004年 | 68篇 |
2003年 | 63篇 |
2002年 | 79篇 |
2001年 | 42篇 |
2000年 | 40篇 |
1999年 | 33篇 |
1998年 | 39篇 |
1997年 | 39篇 |
1996年 | 31篇 |
1995年 | 30篇 |
1994年 | 25篇 |
1993年 | 30篇 |
1992年 | 16篇 |
1991年 | 21篇 |
1990年 | 22篇 |
1989年 | 18篇 |
1988年 | 17篇 |
1987年 | 13篇 |
1986年 | 16篇 |
1985年 | 13篇 |
1984年 | 16篇 |
1983年 | 15篇 |
1982年 | 15篇 |
1981年 | 18篇 |
1980年 | 11篇 |
1979年 | 16篇 |
1978年 | 14篇 |
1976年 | 16篇 |
1975年 | 10篇 |
1974年 | 9篇 |
1972年 | 7篇 |
排序方式: 共有2311条查询结果,搜索用时 15 毫秒
71.
72.
Alexandre Ruellan Violette Ducruet Audrey Gratia Lidia Saelices Jimenez Alain Guinault Cyrille Sollogoub Guillaume Chollet Sandra Domenek 《Polymer International》2016,65(6):683-690
Polylactide (PLA) is the most used biodegradable and biobased food packaging polymer for rigid containers and films. However, its low ductility is a hurdle for increasing its applications in flexible food packaging. A solution is the use of additives. Palm oil deodorizer distillate (PODC) is revealed to be an excellent additive promoting PLA ductility. PODC is a by‐product of vegetable oil refining, which is available in stable quality and in sufficient amounts. Amorphous PLA/PODC blends had an elongation at break of around 130% and that of semi‐crystalline blends was still around 55% compared to the initial 5% of neat PLA. At the same time the PLA rigidity and high glass transition temperatures were kept. PODC was also a very efficient processing aid, allowing for film blow extrusion. The blends were stable in properties during six months without exudation. They complied with legal norms of Food Contact Materials (EU 10/2011) and induced no sensorial alteration of packed food. Therefore PODC is a very interesting alternative to common plasticizers for the production of flexible PLA packaging films. © 2016 Society of Chemical Industry 相似文献
73.
Densification of 8Y‐Tetragonal‐Stabilized Zirconia Optoceramics with Improved Optical Properties by Y Segregation 下载免费PDF全文
Mythili Prakasam François Weill Eric Lebraud Oudomsack Viraphong Sonia Buffiére Alain Largeteau 《International Journal of Applied Ceramic Technology》2016,13(5):904-911
8% Yttria‐stabilized zironcia (8YSZ) transparent ceramics have a wide technological applications. Segregation of the Y around the grain boundaries is favored by slow heating rate. The optimized sintering parameters helped in obtaining transparent ceramics of 8YSZ with a high percentage of cubic phase in addition to the presence of tetragonal phase. HRTEM was used to verify the grain growth suppression and to observe the presence of the cubic phase. The presence of cubic phase has suppressed the grain growth, which increased the transparency in the visible and infrared region without the addition of dopants or by utilizing high pressure. 相似文献
74.
Topics in Catalysis - This Synthetic Gas Bench (SGB) study focuses on the effect of cell geometry and wall thickness on the gasoline NO x trap functionality. The data show that besides a NO x trap... 相似文献
75.
Smet C Leroy A Sillen A Wieruszeski JM Landrieu I Lippens G 《Chembiochem : a European journal of chemical biology》2004,5(12):1639-1646
A combined strategy to obtain a partial NMR assignment of the neuronal Tau protein is presented. Confronted with the extreme spectral degeneracy that the spectrum of this 441 amino acid long unstructured protein presents, we have introduced a graphical procedure based on residue type-specific product planes. Combining this strategy with the search for pairwise motifs, and combining the spectra of different Tau isoforms and even of peptides derived from the native sequence, we arrive at a partial assignment that is sufficient to map the interactions of Tau with its molecular partners. The obtained assignments equally confirm the absence of regular secondary structure in the isolated protein. 相似文献
76.
Thomas Schareina Xiao-Feng Wu Alexander Zapf Alain Cotté Matthias Gotta Matthias Beller 《Topics in Catalysis》2012,55(7-10):426-431
The first copper-catalyzed trifluoromethylation of aryl halides was developed that utilizes inexpensive trifluoroacetates. Providing low concentrations of the most economically attractive and atom-efficient trifluoromethylation reagent this new protocol is advantageous compared to known procedures both economically and ecologically. 相似文献
77.
Dr. Morgan Le Naour Dr. Veronique Leclerc Dr. Amaury Farce Dr. Daniel‐Henri Caignard Dr. Nathalie Hennuyer Prof. Bart Staels Dr. Valérie Audinot‐Bouchez Dr. Jean‐Albert Boutin Dr. Michel Lonchampt Dr. Catherine Dacquet Prof. Alain Ktorza Prof. Pascal Berthelot Dr. Nicolas Lebegue 《ChemMedChem》2012,7(12):2179-2193
Compounds that simultaneously activate peroxisome proliferator‐activated receptor (PPAR) subtypes α and γ have the potential to effectively treat dyslipidemia and type 2 diabetes (T2D) in a single pharmaceutically active molecule. The frequently observed side effects of selective PPARγ agonists, such as edema and weight gain, were expected to be overcome by using additive PPARα activity, leading to dual PPARα/γ agonists with balanced activity for both subtypes. Herein we report the discovery, synthesis, and optimization of a new series of α‐ethoxyphenylpropionic acid bearing 5‐ or 6‐substituted indoles. The incorporation of oxime ethers on the carbonyl portion of the benzoyl group can bring the PPARα/γ potency ratio equal to or slightly greater than one, as is the case for compounds 20 c and 21 a . Compound 20 c shows high efficacy in an ob/ob mouse model of T2D and dyslipidemia, similar to that of rosiglitazone and tesaglitazar, but with a significant increase in body weight gain. In contrast, compound 21 a , less potent as a dual PPARα/γ activator than 20 c , showed an interesting pharmacological profile, as it elicits a decrease in body weight relative to reference compounds. 相似文献
78.
79.
Dual,Site‐Specific Modification of Antibodies by Using Solid‐Phase Immobilized Microbial Transglutaminase 下载免费PDF全文
Dr. Philipp R. Spycher Christian A. Amann Jöri E. Wehrmüller David R. Hurwitz Olivier Kreis Daniel Messmer Andreas Ritler Dr. Andreas Küchler Alain Blanc Dr. Martin Béhé Prof. Dr. Peter Walde Prof. Dr. Roger Schibli 《Chembiochem : a European journal of chemical biology》2017,18(19):1923-1927
Microbial transglutaminase (MTG) was stably solid‐phase immobilized on glass microbeads by using a second‐generation dendronized polymer. Immobilized MTG enabled the efficient generation of site‐specifically conjugated proteins, including antibody fragments, as well as whole antibodies through distinct glutamines and, unprecedentedly, also through lysines with various bifunctional substrates with defined stoichiometries. With this method, we generated dual, site‐specifically modified antibodies comprising a fluorescent probe and a metal chelator for radiolabeling—a strategy anticipated to design antibodies for imaging and simultaneous therapy. Furthermore, we provide evidence that immobilized MTG features higher siteselectivity than soluble MTG. 相似文献
80.
Alain Tundidor-Camba Nélida Araya Carmen M. González-Henríquez Luis H. Tagle René A. Hauyon Patricio A. Sobarzo Fidel E. Rodríguez-González Ignacio A. Jessop Gonzalo Recabarren-Gajardo Claudio A. Terraza 《应用聚合物科学杂志》2019,136(42):48055
Three new diamines derived from epoxide compounds were synthesized. The preparation of diamine monomers implied the reaction between a phenoxyalkyloxirane (alkyl: H, methyl, isopropyl) and bisphenol A, obtaining the respective aliphatic diols, which produced the corresponding dinitro derivatives. Finally, these derivatives were reduced by using palladium/carbon activated as catalyst and hydrazine as a hydrogen source. Then, six oligomeric poly(ether-azomethine)s (PEAzMs) were obtained from a polycondensation reaction between the new diamines and bis(4-formylbiphenyl-4-yl)dialkylsilane (alkyl: methyl, phenyl) with 84–93% yields. The structural characterization of the diamines and PEAzMs was performed by elemental analysis, infrared spectroscopy, and nuclear magnetic resonance spectroscopy (1H, 13C, and 29Si). Furthermore, polymers were analyzed by solubility tests, gel permeation chromatography, ultraviolet–visible (UV–vis) spectroscopy, thermogravimetry, and differential scanning calorimetry analysis. The results showed PEAzMs with 2–11 repetitive units, where the design of the monomers allowed to obtain improved solution processability in comparison with previously reported silylated poly(azomethine)s and good thermal stability. Additionally, all samples showed high transparency in the UV–vis region. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48055. 相似文献