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41.
Vitaliy Kholodnyy Borys Dzyuba Marek Rodina Hermes Bloomfield-Gadêlha Manabu Yoshida Jacky Cosson Sergii Boryshpolets 《International journal of molecular sciences》2021,22(17)
The fertilization of freshwater fish occurs in an environment that may negatively affect the gametes; therefore, the specific mechanisms triggering the encounters of gametes would be highly expedient. The egg and ovarian fluid are likely the major sources of these triggers, which we confirmed here for rainbow trout (Oncorhynchus mykiss). The ovarian fluid affected significantly spermatozoa performance: it supported high velocity for a longer period and changed the motility pattern from tumbling in water to straightforward moving in the ovarian fluid. Rainbow trout ovarian fluid induced a trapping chemotaxis-like effect on activated male gametes, and this effect depended on the properties of the activating medium. The interaction of the spermatozoa with the attracting agents was accompanied by the “turn-and-run” behavior involving asymmetric flagellar beating and Ca2+ concentration bursts in the bent flagellum segment, which are characteristic of the chemotactic response. Ovarian fluid created the optimal environment for rainbow trout spermatozoa performance, and the individual peculiarities of the egg (ovarian fluid)–sperm interaction reflect the specific features of the spawning process in this species. 相似文献
42.
Jacky M. K. Kwong Joseph Caprioli Ying H. Sze Feng J. Yu King K. Li Chi H. To Thomas C. Lam 《International journal of molecular sciences》2021,22(16)
To investigate the retinal proteins associated with primary and secondary retinal ganglion cell (RGC) degeneration and explore their molecular pathways, SWATH label-free and target-based mass spectrometry was employed to identify the proteomes in various retinal locations in response to localized optic nerve injury. Unilateral partial optic nerve transection (pONT) was performed on adult Wistar rats and their retinas were harvested 2 weeks later. To confirm the separation of primary and secondary RGC degeneration, immunohistochemistry of RNA binding protein with multiple splicing (RBPMS) and glial fibrillary acidic protein (GFAP) was performed on retinal whole-mounts. Retinal proteomes in the temporal and nasal quadrants were evaluated with high resolution hybrid quadrupole time-of-flight mass spectrometry (QTOF-MS), and SWATH-based acquisition, and their expression was compared to the corresponding retinal quadrant in contralateral control eyes and further validated by multiple reaction monitoring mass spectrometry (MRM-MS). A total of 3641 proteins (FDR < 1%) were identified using QTOF-MS. The raw data are available via ProteomeXchange with the identifier PXD026783. Bioinformatics data analysis showed that there were 37 upregulated and 25 downregulated proteins in the temporal quadrant, whereas 20 and five proteins were upregulated and downregulated, respectively, in the nasal quadrant, respectively (n = 4, p < 0.05; fold change ≥ 1.4-fold or ≤0.7). Six proteins were regulated in both the temporal and the nasal quadrants, including CLU, GFAP, GNG5, IRF2BPL, L1CAM, and CPLX1. Linear regression analysis indicated a strong association between the data obtained by means of SWATH-MS and MRM-MS (temporal, R2 = 0.97; nasal, R2 = 0.96). Gene ontology analysis revealed statistically significant changes in the biological processes and cellular components of primary RGC degeneration. The majority of the significant changes in structural, signaling, and cell death proteins were associated with the loss of RGCs in the area of primary RGC degeneration. The combined use of SWATH-MS and MRM-MS methods detects and quantifies regional changes of retinal protein expressions after localized injury. Future investigation with this integrated approach will significantly increase the understanding of diverse processes of progressive RGC degeneration from a proteomic prospective. 相似文献
43.
Optical image encryption based on interference has attracted a lot of attention recently. The technique employs two pure phase masks derived from the complex field of the image in the Fresnel diffraction domain. The image decryption procedure can be carried out by inverse Fresnel transformation of the summation of two pure phase masks. However, the silhouette of the original image, which is recovered by either of the two phase-only masks, impedes the application of this technique. In this paper, a very simple method for binary image encryption based on interference of two phase-only masks is proposed without any silhouette problem. The binary image in combination with a random phase mask is separated into two phase-only masks directly, and the decryption by summation of the two masks can be performed digitally or optically. In this paper, the encryption and decryption processes are analyzed, after which both the optical simulation and the experimental results based on single-beam holography are given to demonstrate the feasibility of the encryption method. As information nowadays is mainly digitized into binary codes, the proposed encryption method may find applications in the information processing field. 相似文献
44.
Helander MG Morse GE Qiu J Castrucci JS Bender TP Lu ZH 《ACS applied materials & interfaces》2010,2(11):3147-3152
A fluorinated phenoxy boron subphthalocyanine (BsubPc) is shown to function as a fluorescent dopant emitter in small molecule organic light emitting diodes (OLEDs). Narrow electroluminescence (EL) emission with a full width at half-maximum of ~30 nm was observed regardless of the host used, indicating that this narrow EL is intrinsic to the BsubPc molecule. A bathochromic shift and the growth of a new EL peak at higher wavelengths with increasing doping concentration were found to be a result of molecular aggregation. Excitation of BsubPc by direct charge trapping as well as Fo?rster resonant energy transfer were shown using different host molecules. A maximum efficiency of 1.5 cd/A was achieved for a 4,4'-N,N'-dicarbazole-biphenyl (CBP) host. 相似文献
45.
We describe a novel method of angle measurement by borrowing the concept of the circular Dammann grating (CDG). A three-order CDG is employed in this experiment. The displacement of the tilted angle can be determined accurately by measuring the projection from the distorted CDG image. This method is controlled only by the initial radius of the image and the converging ratio of the lens. Compared with conventional techniques, this technique has the advantages of a simple design with superior resolution to within 1 degree, low cost, and compactness. A theoretical analysis together with experimental results is presented. 相似文献
46.
Caroline A Toussaint Franoise Mdale Armel Davenel Benoît Fauconneau Pierrick Haffray Serge Akoka 《Journal of the science of food and agriculture》2002,82(2):173-178
A low‐cost, accurate NMR method was developed to determine the lipid content in fish flesh. The fish samples are dried before NMR measurements, and the method is self‐calibrated with an oil reference. The NMR technique gave an intermediate fat content value, 4.7% lower in relative value than those obtained by a chemical cold extraction method and 6.7% higher than those from a petroleum ether extraction method at high temperature. Taking into account this systematic bias, the prediction error was only 3 g kg?1 fat content between NMR and Soxhlet method determinations (R2 = 0.98). The NMR technique thus offers a promising alternative method for determining the lipid content in previously dried fish flesh, since it is rapid, easily usable and solvent‐free, unlike chemical extraction methods. Furthermore, this accurate NMR method should be valuable to calibrate the fast but less accurate NMR, NIR and microwave methods based on fresh samples and to estimate the fat content in other animal meats when the fat is maintained in an amorphous state. © 2001 Society of Chemical Industry 相似文献
47.
This study characterized chemicals released into a chamber in the process of cooking microwave popcorn. Seventeen types of microwave popcorn from eight different brands were studied. The work proceeded in two phases: phase one investigated chemicals emitted during popping and opening, phase two investigated chemicals emitted at discrete intervals from 0-40 minutes post-pop opening. The research was performed using a microwave oven enclosed in a chamber with ports for air sampling of particulate matter (PM) and volatile organic compounds (VOCs). VOCs in the air samples were identified and quantified using gas chromatography/mass spectrometry (GC/MS). PM was characterized using both an aerodynamic particle sizer (APS) and a scanning mobility particle sizer (SMPS) to cover a full range of emitted sizes. The compounds measured during popping and opening included butter flavoring components such as diacetyl, butyric acid, acetoin, propylene glycol, 2-nonanone, and triacetin and bag components such as p-xylene and perfluorinated alcohol 8:2 telomer. The greatest chemical quantity is emitted when the bag is opened post-popping; more than 80% of the total chemical emissions occur at this time. 相似文献
48.
The yeast Zygosaccharomyces rouxii is known for its high tolerance to osmotic stress, which is thought to be caused by sets of specific genes. Relatively few Z. rouxii genes have been identified so far, all of them having homologues in Saccharomyces cerevisiae; none of them was Z. rouxii-specific. Most of the known Z. rouxii genes were isolated from two wild-type strains, ATCC 2623 and ATCC 42981. In this study, we compared these two strains with regard to some of their morphological, physiological and genomic properties. Important differences were found in their salt tolerance and assimilation of glycerol and karyotype; slight differences were also present in their cell morphology. The ATCC 42981 strain showed a higher resistance to salts, higher glycerol production and, unlike ATCC 2623, was able to assimilate glycerol. Under conditions of osmotic stress, the glycerol production in both Z. rouxii strains was much lower than in a S. cerevisiae S288c culture, which suggested the presence of a system that efficiently retains glycerol inside Z. rouxii cells. The karyotype analysis revealed that ATCC 42981 cells contain more chromosomes and have a bigger genome size than those of ATCC 2623. 相似文献
49.
The strength of the orienting response (OR) to a light and its associability was studied in three experiments. In Experiment 1, three groups of rats received serial conditioning in which the light served as the first element of a serial compound. For Group Diff the light was followed by a conditioned stimulus (CS) of 10-s duration on some trials and by a different CS of 30-s duration on others. For the other groups, the light was also followed by a different stimuli, but these had equivalent durations. This procedure resulted in stronger OR toward the light in Group Diff than in either of the other groups. In Experiments 2 and 3 the OR was stronger to a light that was followed by a 10-s CS on some trials and on a 30-s CS on others than to one that was followed by different CSs that were both randomly either 10 s or 30 s. Following this training, both excitatory and inhibitory conditioning with the light was faster in those groups for which the light elicited a strong rather than a weak OR. These results are most readily explained by the proposal that the strength of the OR toward a CS is determined by the accuracy with which the value of its immediate consequences can be predicted and that this OR can be used as an index of the associability of the CS. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Ruth M. E. Greene Kenneth J. Ivin Jacky Kress John A. Osborn John J. Rooney 《Polymer International》1989,21(3):237-242
Eight tungsten-carbene complex catalysts of the type W(CHCMe3)L1L2L3L4, where the ligands L are various combinations of OCH2CMe3, SO3CF3, OSiPh3, Br and I, have been used, in the presence and absence of GaBr3, to polymerize norbornene and six of its methyl derivatives by ring opening. The microstructure of the polymers was determined from their 13C NMR spectra; values of cis content, cis-trans blockiness, ring-dyad tacticity and head-tail bias were derived as appropriate to each system. The results are discussed in terms of electronic and steric effects in the propagating carbene complexes. 相似文献