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31.
Minati Satpathy Liya Wang Rafal Zielinski Weiping Qian Malgorzata Lipowska Jacek Capala Gee Young Lee Hong Xu Y. Andrew Wang Hui Mao Lily Yang 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(3):544-555
Despite advances in cancer diagnosis and treatment, ovarian cancer remains one of the most fatal cancer types. The development of targeted nanoparticle imaging probes and therapeutics offers promising approaches for early detection and effective treatment of ovarian cancer. In this study, HER‐2 targeted magnetic iron oxide nanoparticles (IONPs) are developed by conjugating a high affinity and small size HER‐2 affibody that is labeled with a unique near infrared dye (NIR‐830) to the nanoparticles. Using a clinically relevant orthotopic human ovarian tumor xenograft model, it is shown that HER‐2 targeted IONPs are selectively delivered into both primary and disseminated ovarian tumors, enabling non‐invasive optical and MR imaging of the tumors as small as 1 mm in the peritoneal cavity. It is determined that HER‐2 targeted delivery of the IONPs is essential for specific and sensitive imaging of the HER‐2 positive tumor since we are unable to detect the imaging signal in the tumors following systemic delivery of non‐targeted IONPs into the mice bearing HER‐2 positive SKOV3 tumors. Furthermore, imaging signals and the IONPs are not detected in HER‐2 low expressing OVCAR3 tumors after systemic delivery of HER‐2 targeted‐IONPs. Since HER‐2 is expressed in a high percentage of ovarian cancers, the HER‐2 targeted dual imaging modality IONPs have potential for the development of novel targeted imaging and therapeutic nanoparticles for ovarian cancer detection, targeted drug delivery, and image‐guided therapy and surgery. 相似文献
32.
Thorsten Falk Ralf Heese Christian Kaspar Malgorzata Mochol Daniel Pfeiffer Michael Thygs Robert Tolksdorf 《Informatik-Spektrum》2006,29(3):201-209
Zusammenfassung The importance of the Internet for job procurement is increasing for the reason that three quarters of the people in the employment age are online. On the other hand because ever more companies are publishing their job offers on the Web. However, due to the large number of openings published online it is almost impossible for job seekers and job portals to gain an overview of the entire employment market. Since job offers lack semantically meaningful annotations, the search and integration into databases are made highly difficult. Applying Semantic Web technologies to the e-recruitment process provides advantages for all participants in the market. In this paper we describe a method for analysing the domain-specific language of an application domain. We use this method to describe the e-recruitment process and the necessary ontologies for annotating job offers and job applications. In conclusion, we present the prototypical implementation of the scenario based on Semantic Web, especially semantic matching. 相似文献
33.
Let wt be a wire in a combinational Boolean network. There may exist a wire wa such that when wa is added and wt is removed, the overall circuit functionality is unchanged. Redundancy-addition-and-removal (RAR) is an efficient technique to find such a wa. The idea is to add a redundant alternative wire wa to make the target wire wt redundant. However, as long as the addition of wa together with the removal of wt does not change the overall functionality of the circuit, wires that are added and removed do not necessarily need to be redundant. This raises a question about the existence of alternative wires. Why can one wire replace another wire in a combinational Boolean network? In this paper, we analyze theoretically the existence of alternative wires and model it as an error-cancellation problem. The two existing rewiring techniques, the redundancy-addition-and-removal and the global flow optimization, are unified under the proposed generalized model. 相似文献
34.
Any solid oxide-originated catalyst is extremely heterogeneous due to several factors. First, it may consist of various phases,
each exposing different surfaces characterized by different electronic, and thus catalytic, properties. However, even a particular
surface of a chosen phase is heterogeneous as it consists of different chemical elements connected in polyhedra bonded with
each other via corners and/or edges and/or walls. In addition, dopants and supports change properties of the surface by enriching
its heterogeneity. In the following, the role of dopants as potential sources of surface heterogeneity is discussed, using
vanadia as an example. 相似文献
35.
Maciej Wisniewski Jan Szymanowski Wladyslaw Walkowiak Malgorzata Michalewska 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1992,53(3):243-251
Interfacial tension isotherms were determined in hydrocarbon-water systems for 4-alkylphenylamines containing from 6 to 16 carbon atoms in their alkyl chains, and the surface excess isotherms were computed and interpreted using various adsorption isotherms. Palladium(II) was extracted with 4-alkylphenylamines from 3 M HCI solutions. The maximum extraction rate of palladium(II) is observed for 4-decyl- and 4-dodecylphenylamines which exhibit good interfacial activity. Compounds soluble in the aqueous phase (4-hexylphenylamine) or in toluene (4-hexadecylphenylamine) extract palladium(II) slower than 4-decyl- and 4-dodecyl- phenylamines. 相似文献
36.
We report a substantial advance in dye laser performance using a zig-zag optical cavity. This configuration drastically reduces the effects of intrapulse medium disturbances due to acoustics and thermal lensing on pulse duration, beam quality, and extraction efficiency. Laser outputs of up to 2 J were observed from Coumarin-498 dye pumped by a KrF excimer laser. The dye laser output faithfully replicates the hat-top KrF laser pump pulse over the entire 1.7-μs pulse duration. An intrinsic laser photon conversion efficiency (Photonsin/Photonsabsorbed) of 44% was measured. When unstable resonator optics were used, beam qualities of about 2 XDL were measured 相似文献
37.
Klimek D. Hsia J. Jacob J. Trainor D. Duzy C. Hyman H. 《Quantum Electronics, IEEE Journal of》1981,17(9):1847-1855
Various kinetic issues that are important for modeling the performance of large-scale-size krypton fluoride lasers have been investigated. These kinetic issues include: electron quenching, photoionization from excited rare gas atoms, fuel burn-up, and the accessibility of higher lying levels of KrF* to be effectively stimulated by the laser cavity flux. The results of these studies have been incorporated into a laser kinetics code. Absorption and gain measurements have been carried out over a broad range of conditions to provide a data base to test the code's accuracy and to make subsequent refinements. The code projections for short-pulse operating conditions important for laser-fusion applications are presented. 相似文献
38.
Regulation of progesterone biosynthesis in human placental mitochondria by Krebs cycle metabolites 总被引:1,自引:0,他引:1
J Klimek W Boguslawski B Tialowska L Zelewski 《Canadian Metallurgical Quarterly》1976,23(2-3):185-192
1. 2-Oxoglutarate, succinate, fumarate, malate and citrate, cis-aconitate and isocitrate stimulate conversion of cholesterol to progesterone in human placental mitochondria. 2. The stimulatory effect of dicarboxylic and tricarboxylic acids depends on the activity of malate dehydrogenase (decarboxylating) (NADP+) (EC 1.1.1.40) and isocitrate dehydrogenase (NADP+) (EC 1.1.1.42), respectively. 相似文献
39.
Effects of a nonuniform vertical profile of chlorophyll concentration on remote-sensing reflectance of the ocean 总被引:2,自引:0,他引:2
Numerical simulations of radiative transfer were used to examine the effects of a nonuniform vertical profile of the inherent optical properties of the water column associated with the vertical profile of chlorophyll concentration, Chl(z), on the spectral remote-sensing reflectance, Rrs(gamma), of the ocean. Using the Gaussian function that describes the Chl(z) profile, we simulated a relatively broad range of open-ocean conditions characterized by the presence of a subsurface Chl maximum at depths greater than or equal to 20 m. The simulations for a vertically nonuniform Chl(z) were compared with reference simulations for a homogeneous ocean whose Chl was identical to the surface Chl of inhomogeneous cases. The range of values for the Gaussian parameters that produce significant differences in Rrs(gamma) (> 5%) was determined. For some vertical structures of Chl(z) considered, the magnitude of Rrs(gamma) and the blue-to-green band ratios of Rrs(gamma) differ significantly from the reference values of homogeneous ocean (> 70% in extreme cases of low surface chlorophyll of 0.02 mg m(-3) and shallow pigment maximum at 20 m). The differences are small or negligible when the nonuniform profiles are characterized by a surface Chl greater than 0.4 mg m(-3) or a depth of Chl maximum greater than 45 m (65 m in extremely clear waters with a surface Chl of 0.02 mg m(-3) or less). The comparison of modeling results with the current algorithm for retrieving the global distribution of chlorophyll from satellite imagery of ocean color suggests that strong effects of the subsurface chlorophyll maximum on reflectance at low surface chlorophyll concentrations can lead to a severalfold overestimation in the algorithm-derived surface chlorophyll. Examples of field data from the Sea of Japan and the north polar Atlantic Ocean are used to illustrate various nonuniform pigment profiles and their effect on the blue-to-green ratio of Rrs(gamma). 相似文献
40.
Mariusz Andrzejczuk Marcin Rasiski Agata Roguska Marcin Pisarek Malgorzata Lewandowska 《Microscopy research and technique》2019,82(3):173-177
To characterize complex, three‐dimensional nanostructures, modern microscopy techniques are needed, such as electron tomography and focused ion beam (FIB) sectioning. The aim of this study was to apply these two techniques to characterize TiO2 nanotubes in terms of their size, shape, volume, porosity, geometric surface area, and specific surface area (SSA). For these experiments, titania nanotubes were fabricated by means of the electrochemical oxidation of titanium at a voltage of 20 V for 2 hr followed by heat treatment at 450°C for 3 hr to change the amorphous structure into a crystalline anatase structure. The quantitative data obtained from the FIB and electron tomography reconstructions show a high similarity in porosity and some differences in SSA. These might be the result of differences in resolution between the two reconstruction techniques. 相似文献