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191.
Two siloxane‐containing polyazomethines (PAZx) blended with SiO2 were investigated. SiO2 was obtained by sol‐gel method. The size of obtained SiO2 particles was about 408 nm as was confirmed by SEM technique. For the blended with silica polymers absorption UV‐vis properties were tested and compare with unblended ones. Electrical behavior of the two kind devices indium tin oxide (ITO)/PAZx : SiO2/Al and ITO/PEDOT : PSS/PAZx : SiO2/Al were tested by impedance spectroscopy in dark and under illumination (halogen lamp, 100 mW/cm2) in the frequency range of 1 Hz to 1 MHz with maximum voltage value of 20 mV. For all measured devices, Nyquist plots were presented. PEDOT : PSS interlayer improved electrical properties of made prototype polymeric solar cells. Blending PAZx with silica increased conductivity from 10–15 to 10–8 S/cm. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
192.
Marta Klak Ilona ojszczyk Andrzej Berman Grzegorz Tymicki Anna Adamiok-Ostrowska Maciej Sierakowski Radosaw Olkowski Andrzej Antoni Szczepankiewicz Artur Kamiski Agnieszka Dobrzy Micha Wszoa 《International journal of molecular sciences》2021,22(13)
Due to the limited number of organ donors, 3D printing of organs is a promising technique. Tissue engineering is increasingly using xenogeneic material for this purpose. This study was aimed at assessing the safety of decellularized porcine pancreas, together with the analysis of the risk of an undesirable immune response. We tested eight variants of the decellularization process. We determined the following impacts: rinsing agents (PBS/NH3·H2O), temperature conditions (4 °C/24 °C), and the grinding method of native material (ground/cut). To assess the quality of the extracellular matrix after the completed decellularization process, analyses of the following were performed: DNA concentration, fat content, microscopic evaluation, proteolysis, material cytotoxicity, and most importantly, the Triton X-100 content. Our analyses showed that we obtained a product with an extremely low detergent content with negligible residual DNA content. The obtained results confirmed the performed histological and immuno-fluorescence staining. Moreover, the TEM microscopic analysis proved that the correct collagen structure was preserved after the decellularization process. Based on the obtained results, we chose the most favorable variant in terms of quality and biology. The method we chose is an effective and safe method that gives a chance for the development of transplant and regenerative medicine. 相似文献
193.
Dorota Pierzchaa Kamila Liput Agnieszka Korwin-Kossakowska Magdalena Oguszka Ewa Poawska Agata Nawrocka Pawe Urbaski Aleksandra Ciepoch Edyta Juszczuk-Kubiak Adam Lepczyski Brygida
laska Krzysztof Kowal Marinus F. W. te Pas Magdalena
miech Pawe Leszczyski Hiroaki Taniguchi Leyland Fraser Przemysaw Sobiech Mateusz Sachajko Magdalena Herudzinska Chandra S. Pareek Mariusz Pierzchaa 《International journal of molecular sciences》2021,22(13)
The molecular mechanism underlying embryonic implantation is vital to understand the correct communications between endometrium and developing conceptus during early stages of pregnancy. This study’s objective was to determine molecular changes in the uterine endometrial proteome during the preimplantation and peri-implantation between 9 days (9D), 12 days (12D), and 16 days (16D) of pregnant Polish Large White (PLW) gilts. 2DE-MALDI-TOF/TOF and ClueGOTM approaches were employed to analyse the biological networks and molecular changes in porcine endometrial proteome during maternal recognition of pregnancy. A total of sixteen differentially expressed proteins (DEPs) were identified using 2-DE gels and MALDI-TOF/TOF mass spectrometry. Comparison between 9D and 12D of pregnancy identified APOA1, CAPZB, LDHB, CCT5, ANXA4, CFB, TTR upregulated DEPs, and ANXA5, SMS downregulated DEPs. Comparison between 9D and 16D of pregnancy identified HP, APOA1, ACTB, CCT5, ANXA4, CFB upregulated DEPs and ANXA5, SMS, LDHB, ACTR3, HP, ENO3, OAT downregulated DEPs. However, a comparison between 12D and 16D of pregnancy identified HP, ACTB upregulated DEPs, and CRYM, ANXA4, ANXA5, CAPZB, LDHB, ACTR3, CCT5, ENO3, OAT, TTR down-regulated DEPs. Outcomes of this study revealed key proteins and their interactions with metabolic pathways involved in the recognition and establishment of early pregnancy in PLW gilts. 相似文献
194.
Lakshmipriya Perincherry Monika Urbaniak Izabela Pawowicz Karolina Kotowska Agnieszka Wakiewicz ukasz Stpie 《International journal of molecular sciences》2021,22(18)
Fusarium species are common plant pathogens that cause several important diseases. They produce a wide range of secondary metabolites, among which mycotoxins and extracellular cell wall-degrading enzymes (CWDEs) contribute to weakening and invading the host plant successfully. Two species of Fusarium isolated from peas were monitored for their expression profile of three cell wall-degrading enzyme coding genes upon culturing with extracts from resistant (Sokolik) and susceptible (Santana) pea cultivars. The extracts from Santana induced a sudden increase in the gene expression, whereas Sokolik elicited a reduced expression. The coherent observation was that the biochemical profile of the host plant plays a major role in regulating the fungal gene expression. In order to uncover the fungal characteristics in planta, both pea cultivars were infected with two strains each of F. proliferatum and F. oxysporum on the 30th day of growth. The enzyme activity assays from both roots and rhizosphere indicated that more enzymes were used for degrading the cell wall of the resistant host compared to the susceptible host. The most commonly produced enzymes were cellulase, β-glucosidase, xylanase, pectinase and lipase, where the pathogen selectively degraded the components of both the primary and secondary cell walls. The levels of beauvericin accumulated in the infected roots of both cultivars were also monitored. There was a difference between the levels of beauvericin accumulated in both the cultivars, where the susceptible cultivar had more beauvericin than the resistant one, showing that the plants susceptible to the pathogen were also susceptible to the toxin accumulation. 相似文献
195.
Agnieszka Wrblewska Anna Fajdek Joanna Wajzberg Eugeniusz Milchert 《Journal of hazardous materials》2009,170(1):405-410
Epoxidation of allyl alcohol with 30 wt% hydrogen peroxide over Ti-MCM-41 catalyst under atmospheric pressure and in the presence of methanol as a solvent has been studied. The influence of the following parameters: temperature (20–60 °C), the molar ratio of AA/H2O2 (0.5–5), methanol concentration (5–90 wt%), catalyst concentration (0.1–5.0 wt%) and reaction time (5–180 min) has been investigated. The process has been described by the following functions: the selectivity of transformation to glycidol in relation to allyl alcohol consumed, conversions of the substrates and selectivity of transformation to organic compounds in relation to hydrogen peroxide consumed. The technological parameters, at which the functions describing the process take the optimum values, have been established. 相似文献
196.
197.
Agnieszka Lisowska 《Journal of Mathematical Imaging and Vision》2011,39(2):180-192
In the paper the moments-based fast wedgelet transform has been presented. In order to perform the classical wedgelet transform one searches the whole wedgelets’ dictionary to find the best matching. Whereas in the proposed method the parameters of wedgelet are computed directly from an image basing on moments computation. Such parameters describe wedgelet reflecting the edge present in the image. However, such wedgelet is not necessarily the best one in the meaning of Mean Square Error. So, to overcome that drawback, the method which improves the matching result has also been proposed. It works in the way that the better matching one needs to obtain the longer time it takes. The proposed transform works in linear time with respect to the number of pixels of the full quadtree decomposition of an image. More precisely, for an image of size N×N pixels the time complexity of the proposed wedgelet transform is O(N 2log 2 N). 相似文献
198.
Application of lyophilization to prepare the nitrifying bacterial biofilm for imaging with scanning electron microscopy 总被引:1,自引:0,他引:1
Structure of bacterial biofilms may be investigated using several variants of scanning electron microscopy (SEM). We apply lyophilization to prepare nitrifying bacterial biofilm for conventional SEM imaging in high-vacuum mode (CSEM). We therefore replace standard biofilm fixation in glutaraldehyde cross-linking, ethanol dehydration, and critical-point drying (CPD) with less-invasive low-temperature drying by sublimation in vacuum. We compare this approach with: (1) standard preparation with glutaraldehyde fixation, ethanol dehydration, and CPD before CSEM, (2) cryo-sputter preparation of rapidly frozen biofilm in hydrated state (cryo-SEM), and (3) in situ observation without any sample pretreatment in environmental SEM. Combined imaging with these modalities revealed two distinct immobilization patterns on the polyurethane foam: (1) large irregular aggregates (flocs) of bacterial biofilm that exist as irregular biofilm fragments, rope-like structures, or biofilm layers on the foam surface; (2) biofilm threads adherent to the surface of polyurethane foam. Our results indicate that lyophilization was suitable for preservation of bacterial cells and many forms of structure of extracellular matrix. The lyophilized material could be imaged with high resolution (using CSEM) to generate structural information complementary to that obtained with other SEM techniques. 相似文献
199.
200.
Synthesis of Novel Phosphonic‐Type Activity‐Based Probes for Neutrophil Serine Proteases and Their Application in Spleen Lysates of Different Organisms 下载免费PDF全文
Dr. Renata Grzywa Dr. Ewa Burchacka Maria Łęcka Dr. Łukasz Winiarski Maciej Walczak Agnieszka Łupicka‐Słowik Dr. Magdalena Wysocka Prof. Timo Burster Dr. Kamila Bobrek Dr. Keri Csencsits‐Smith Prof. Adam Lesner Dr. Marcin Sieńczyk 《Chembiochem : a European journal of chemical biology》2014,15(17):2605-2612
Neutrophils are a type of granulocyte important in the “first line of defense” of the innate immune system. Upon activation, they facilitate the destruction of invading microorganisms by the production of superoxide radicals, as well as the release of the enzymatic contents of their lysozymes. These enzymes include specific serine proteases: cathepsin G, neutrophil elastase, proteinase 3, as well as the recently discovered neutrophil serine protease 4 (NSP4). Under normal conditions, the proteolytic activity of neutrophil proteases is tightly regulated by endogenous serpins; however, this mechanism can be subverted during tissue stress, thereby resulting in the uncontrolled activity of serine proteases, which induce chronic inflammation and subsequent pathology. Herein, we describe the development of low‐molecular‐weight activity‐based probes that specifically target the active sites of neutrophil proteases. 相似文献