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31.
32.
Drug‐Loaded Multifunctional Nanoparticles Targeted to the Endocardial Layer of the Injured Heart Modulate Hypertrophic Signaling 下载免费PDF全文
Mónica P. A. Ferreira Sanjeev Ranjan Sini Kinnunen Alexandra Correia Virpi Talman Ermei Mäkilä Brianda Barrios‐Lopez Marianna Kemell Vimalkumar Balasubramanian Jarno Salonen Jouni Hirvonen Heikki Ruskoaho Anu J. Airaksinen Hélder A. Santos 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(33)
Ischemic heart disease is the leading cause of death globally. Severe myocardial ischemia results in a massive loss of myocytes and acute myocardial infarction, the endocardium being the most vulnerable region. At present, current therapeutic lines only ameliorate modestly the quality of life of these patients. Here, an engineered nanocarrier is reported for targeted drug delivery into the endocardial layer of the left ventricle for cardiac repair. Biodegradable porous silicon (PSi) nanoparticles are functionalized with atrial natriuretic peptide (ANP), which is known to be expressed predominantly in the endocardium of the failing heart. The ANP–PSi nanoparticles exhibit improved colloidal stability and enhanced cellular interactions with cardiomyocytes and non‐myocytes with minimal toxicity. After confirmation of good retention of the radioisotope 111‐Indium in relevant physiological buffers over 4 h, in vivo single‐photon emission computed tomography (SPECT/CT) imaging and autoradiography demonstrate increased accumulation of ANP–PSi nanoparticles in the ischemic heart, particularly in the endocardial layer of the left ventricle. Moreover, ANP–PSi nanoparticles loaded with a novel cardioprotective small molecule attenuate hypertrophic signaling in the endocardium, demonstrating cardioprotective potential. These results provide unique insights into the development of nanotherapies targeted to the injured region of the myocardium. 相似文献
33.
Davor Janjatović Maja Benković Siniša Srečec Damir Ježek Igor Špoljarić Ingrid Bauman 《Advanced Powder Technology》2012,23(5):620-631
Soup mixtures represent specific flow characteristics while particles of different sizes and properties form a homogeneous mixture. In such mixtures, particle–particle interactions differ with addition of different fat types. This study was done to present a characterization and comparison of the cohesion index, powder flow speed dependency and caking properties of four different aggregates of fat particles with three different moisture contents, used in various compositions of powdered soup concentrates. ESEM micrographs have shown that different fat types bind particles differently. The moisture content of cream soup concentrates has a significant influence on cake height ratio of all cycles – more moisture causes higher cake height ratios (from rs = 0.86 to rs = 0.76; p < 0.05). Cream soup concentrates cake strength values are also significantly influenced by the mixtures moisture content – higher moisture content samples showed higher cake strength values (rs = 0.73, p < 0.05). There is a significant correlation between compaction coefficients of all speeds and cake height ratios of all cycles for the cream soup concentrates. Combination of measuring techniques (Powder Flow Analyzer, ESEM and Mastersizer) together with Spearman’s Rank Order Correlation, as a method of non-parametric statistics, provides parturient results in characterization of extremely non-homogenous powder mixtures. 相似文献
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35.
Zusammenfassung Es wird ein Verfahren zur kostenminimalen Festlegung einer kapazitätsorientierten Jahresarbeitszeitverteilung für den Produktionsbereich vorgestellt. Dazu wird auf Basis einer vorgegebenen Menge von Schichtplänen eine simultane Auswahl- und Reihenfolgeplanung durchgeführt, die die Jahresarbeitszeitverteilung optimiert. Im Gegensatz zu den gängigen Verfahren zur Jahresarbeitszeitplanung können bei dieser Vorgehensweise die durch die Schichtpläne auferlegten Arbeitszeitrestriktionen sowie die damit verbundenen Kosten im Detail berücksichtigt werden. Der Einfluß planungsrelevanter Parameter auf die resultierende Jahresarbeitszeitverteilung wird ausführlich diskutiert. 相似文献
36.
Stefan Ivić Siniša Družeta Ivana Hreljac 《Structural and Multidisciplinary Optimization》2017,56(2):297-313
The paper deals with the optimization of the S-Lay submarine pipe-laying. The considered laying model is based on a nonlinear elastic beam model with elastic contact interactions with rigid structures of roller supports and the seabed, solved in the Abaqus software. The optimization problem is formulated so as to determine the main parameters of pipe-laying. In order to maximize the efficiency of the optimization procedure, a specialized Particle Swarm Optimization variant is developed. The introduced δ-PSO employs an additional displacement of agent positions, through which the optimization is directed towards solutions based on offshore engineering practice. Two different cases of submarine pipe laying were used for testing. In these tests, the specialized PSO was compared to standard PSO and Mesh Adaptive Direct Search, which it both outperformed. The δ-PSO specialization is easy to implement in PSO or other swarm intelligence methods, and hopefully can provide similar improvements in other applications. 相似文献
37.
Study of the influence of processing parameters on the production of carboxymethylchitin 总被引:1,自引:0,他引:1
Carboxymethylchitin was prepared at different reaction temperatures and from alkali chitin with different concentrations of alkali. Properties of the product were studied. Alkali chitin were prepared using freshly prepared sodium hydroxide of 45, 50, 55, 60 and 65% (w/w) concentration and carboxymethylated using monochloroacetic acid at controlled (35-40 °C) and uncontrolled (30-80 °C) temperature conditions. Molecular weight, viscosity, degree of deacetylation, etc. of the resultant product, i.e. carboxymethylchitin were determined. It was found that the reaction temperature has a profound influence on the property of the product than alkali concentration. A hygroscopic and completely water-soluble product was formed. Optimum conditions for the production of carboxymethylchitin were found to be 60% NaOH concentration and at 35-40 °C reaction temperature. At these conditions, it was obtained with a molecular weight of 4.11×106 Da, viscosity 1926 cP and degree of deacetylation 45.02%. 相似文献
38.
Structure and Disorder in Squaraine–C60 Organic Solar Cells: A Theoretical Description of Molecular Packing and Electronic Coupling at the Donor–Acceptor Interface 下载免费PDF全文
Yao‐Tsung Fu Demetrio A. da Silva Filho Gjergji Sini Abdullah M. Asiri Saadullah Gary Aziz Chad Risko Jean‐Luc Brédas 《Advanced functional materials》2014,24(24):3790-3798
Organic solar cells based on the combination of squaraine dyes (as electron donors) and fullerenes (as electron acceptors) have recently garnered much attention. Here, molecular dynamics simulations are carried out to investigate the evolution of a squaraine–C60 bilayer interface as a function of the orientation and order of the underlying squaraine layer. Electronic couplings between the main electronic states involved in exciton dissociation and charge (polaron pair) recombination are derived for donor–acceptor complexes extracted from the simulations. The results of the combined molecular‐dynamics?quantum‐mechanics approach provide insight into how the degree of molecular order and the dynamics at the interface impact the key processes involved in the photovoltaic effect. 相似文献
39.
Interfaces: Structure and Disorder in Squaraine–C60 Organic Solar Cells: A Theoretical Description of Molecular Packing and Electronic Coupling at the Donor–Acceptor Interface (Adv. Funct. Mater. 24/2014) 下载免费PDF全文
40.
Heikkinen JJ Riihimäki TA Määttä JA Suomela SE Kantomaa J Kulomaa MS Hytönen VP Hormi OE 《ACS applied materials & interfaces》2011,3(7):2240-2245
A stable, bioactive cellulose acetate (CA) surface was developed by functionalizing the surface with highly thermostable avidin form. The CA films were first functionalized with a mixture of 3-aminopropyltrimethoxysilane and tetraethoxysilane to introduce free amino groups onto the surface of CA films. Free amino groups were functionalized with glutaraldehyde to obtain an activated surface for covalent biomolecule immobilization. A genetically engineered, high-affinity biotin-binding protein chimeric avidin, ChiAVD(I117Y), was used for biofunctionalization of the surface. The chimeric avidin protein has an increased stability in chemically harsh conditions and at high temperature when compared to wt (strept)avidin. The biological activity, i.e., biotin-binding capacity, of the immobilized protein was probed by [(3)H]-biotin. The activity of the chimeric avidin on functionalized CA films was fully retained over the three months' study period. The biotin-binding capacity of the immobilized chimeric avidin was compared to that of immobilized streptavidin, chicken avidin, and rhizavidin and significant differences between proteins were detected. The developed material offers a valuable platform for the development of inexpensive in vitro diagnostics and also supports biosensing applications that are required to operate under demanding conditions. 相似文献