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排序方式: 共有286条查询结果,搜索用时 3 毫秒
41.
Marion Brunner Róbert Katona Zsolt Stefánka Thomas Prohaska 《European Food Research and Technology》2010,231(4):623-634
This case study presents a fast and reliable method of combining strontium isotope ratios (87Sr/86Sr) with a multielement pattern (Rb, Sr, Y, Zr, Mo, Cd, Ba, Pb, Th, U, Mg, Ca, Sc, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, As and
rare earth elements) by means of inductively coupled plasma mass spectrometry (ICP-MS) to establish a unique fingerprint of
authentic Szegedi Fűszerpaprika (PDO) and classify authentic and purchased paprika from different known, declared and unknown geographical origin using multivariate
statistical tools (principal component and canonical discriminant analysis). Since paprika represents a processed spice, alterations
in element and Sr isotopic composition throughout the production process were investigated. The Sr source in the final product
was identified to stem from bioavailable Sr sources in soil. Therefore, the ammonium nitrate extract of a soil is sufficient
to establish a Sr fingerprint for agricultural products of a region. As a consequence, the spice paprika can be traced back
to its geographical origin even after processing. 相似文献
42.
Mariana Tasso Thomas Pons Nicolas Lequeux Julie Nguyen Zsolt Lenkei Diana Zala 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(47)
Single‐particle tracking with quantum dots (QDs) constitutes a powerful tool to track the nanoscopic dynamics of individual cell membrane components unveiling their membrane diffusion characteristics. Here, the nano‐resolved population dynamics of QDs is exploited to reconstruct the topography and structural changes of the cell membrane surface with high temporal and spatial resolution. For this proof‐of‐concept study, bright, small, and stable biofunctional QD nanoconstructs are utilized recognizing the endogenous neuronal cannabinoid receptor 1, a highly expressed and fast‐diffusing membrane protein, together with a commercial point‐localization microscope. Rapid QD diffusion on the axonal plasma membrane of cultured hippocampal neurons allows precise reconstruction of the membrane surface in less than 1 min with a spatial resolution of tens of nanometers. Access of the QD nanoconstructs to the synaptic cleft enables rapid 3D topological reconstruction of the entire presynaptic component. Successful reconstruction of membrane nano‐topology and deformation at the second time‐scale is also demonstrated for HEK293 cell filopodia and axons. Named “nanoPaint,” this super‐resolution imaging technique amenable to any endogenous transmembrane target represents a versatile platform to rapidly and accurately reconstruct the cell membrane nano‐topography, thereby enabling the study of the rapid dynamic phenomena involved in neuronal membrane plasticity. 相似文献
43.
Wireless Personal Communications - Wireless mesh networks represent a key architecture on which several communication systems are relaying. Implementations of these networks which apply... 相似文献
44.
Recently, there has been remarkable growth of interest in the development and applications of time-of-flight (ToF) depth cameras. Despite the permanent improvement of their characteristics, the practical applicability of ToF cameras is still limited by low resolution and quality of depth measurements. This has motivated many researchers to combine ToF cameras with other sensors in order to enhance and upsample depth images. In this paper, we review the approaches that couple ToF depth images with high-resolution optical images. Other classes of upsampling methods are also briefly discussed. Finally, we provide an overview of performance evaluation tests presented in the related studies. 相似文献
45.
Wiesel O Tóth IE Boldogkoi Z Hornyák A Bokor V Halász B Gerendai I 《Microscopy research and technique》2004,63(4):244-252
Using the transneuronal viral tracing method, the central nervous system (CNS) connections of the uterine horn were studied in virgin, pregnant, and in lactating rats. The frequency of viral labeling in the brain and the distribution of virus-infected neurons from the uterine horn were compared among groups. There was a marked difference in the frequency of viral labeling in the brain stem. In virgin rats more than half of the brain stems (5 out of 9) were labeled. In contrast, in pregnant animals viral-labeled neurons were detected in only a few cases (3 out of 16) and almost each brain stem of the lactating group was labeled (12 out of 13). A similar, less marked difference was observed in the hypothalamus. The pattern of distribution of infected neurons was similar in each group. In the brain stem, the nucleus of the solitary tract, dorsal motor nucleus of the vagus, area postrema, gigantocellular and paragigantocellular nucleus, ventrolateral medulla, A5 cell group, and caudal raphe nuclei were the most frequently labeled structures. In the diencephalon, viral-infected neurons were detected primarily in the hypothalamic paraventricular nucleus. The telencephalon was devoid of infected cells. Data suggest that the CNS control of the uterine horn varies depending on reproductive status. The low frequency of brain labeling in pregnant rats may be related to the almost complete lack of sympathetic fibers in the uterus prior to parturition and the very high frequency of labeling in lactating animals to the postpartum hyperinnervation of the uterus. 相似文献
46.
Alexandra Kiss Csaba Csikos Zsolt Regdon Zsuzsanna Polgr Lszl Virg Csaba Hegeds 《International journal of molecular sciences》2021,22(16)
Osteosarcoma is a frequent and extremely aggressive type of pediatric cancer. New therapeutic approaches are needed to improve the overall survival of osteosarcoma patients. Our previous results suggest that NMNAT1, a key enzyme in nuclear NAD+ synthesis, facilitates the survival of cisplatin-treated osteosarcoma cells. A high-throughput cytotoxicity screening was performed to identify novel pathways or compounds linked to the cancer-promoting role of NMNAT1. Nine compounds caused higher toxicity in the NMNAT1 KO U2OS cells compared to their wild type counterparts, and actinomycin D (ActD) was the most potent. ActD-treatment of NMNAT1 KO cells increased caspase activity and secondary necrosis. The reduced NAD+ content in NMNAT1 KO cells was further decreased by ActD, which partially inhibited NAD+-dependent enzymes, including the DNA nick sensor enzyme PARP1 and the NAD+-dependent deacetylase SIRT1. Impaired PARP1 activity increased DNA damage in ActD-treated NMNAT1 knockout cells, while SIRT1 impairment increased acetylation of the p53 protein, causing the upregulation of pro-apoptotic proteins (NOXA, BAX). Proliferation was decreased through both PARP- and SIRT-dependent pathways. On the one hand, PARP inhibitors sensitized wild type but not NMNAT1 KO cells to ActD-induced anti-clonogenic effects; on the other hand, over-acetylated p53 induced the expression of the anti-proliferative p21 protein leading to cell cycle arrest. Based on our results, NMNAT1 acts as a survival factor in ActD-treated osteosarcoma cells. By inhibiting both PARP1- and SIRT1-dependent cellular pathways, NMNAT1 inhibition can be a promising new tool in osteosarcoma chemotherapy. 相似文献
47.
We demonstrate, for what is believed to be the first time, the design of diamondlike photonic crystals made by holographic lithography based on five-beam interference. All five beams are launched from the same half-space, and the exposure can easily be realized by a single diffractive optical element. The photonic structure can be constructed through the translation of the interference pattern controlled by the phase shift of laser beams. The proposed holographic lithography is capable of creating series photonic crystals with large photonic bandgaps by adjusting the phase and the wave vector of interfering beams. 相似文献
48.
Katalin Balla Galina A. Kurina Roswitha März 《Journal of Dynamical and Control Systems》2006,12(3):289-311
The index of DAE systems arising from linear quadratic optimal control problems is considered. Necessary and sufficient conditions
ensuring regularity with tractability index one are proved. Then, it is shown that if the control problem DAE is regular with
index one and if the leading term of the DAE to be controlled is given by one full-column-rank and one full-row-rank matrix,
then it has a Hamiltonian inherent explicit ODE. For problems with regular index zero or index one DAEs to be controlled,
the DAE of the control problem is shown to be regular with tractability index one or three, depending on whether the control
coefficient R is singular.
2000 Mathematics Subject Classification.
49N10, 49J15, 34A09.
Supported by the DFG research center MATHEON in Berlin. This work was partially
supported by the Russian Fundamental Research Foundation Project Nos. 02-01-00351
and 06-01-00296. 相似文献
49.
Artur Thernesz Zoltan Varga Istvan Rabi Zsolt Czaltig Maria Lörincova 《Clean Technologies and Environmental Policy》2010,12(2):97-103
The paper presents the results of feasibility study for increase of crude processing capacity and improves of energy efficiency
of crude oil distillation units. Results introduce that boosting up the distillation capacity was solved while keeping the
flexibility of units for processing different type crude oils. Analysis of heat exchanger network resulted significant reduction
in fuel consumption and in CO2 emission (93 × 106 GJ year−1 and 3,030 tCO2 year−1, respectively). Modification of furnace of one of the distillation units showed 63 GJ ktcrude−1 saving in energy and 4.5 tCO2 ktcrude−1 decrease in emission. 相似文献
50.
Mihály Tapolyai Mária Faludi Virág Réti Zsolt Lengvárszky Tibor Szarvas Tibor Fülöp Gabriella Bekő Klára Berta 《Hemodialysis international. International Symposium on Home Hemodialysis》2013,17(3):406-412
Correct estimation of the dialysis patients' hydration status remains an important clinical challenge. Bioimpedance measurements have been validated by various physiological tests, and the use of brain‐type natriuretic peptide (BNP) has been validated by inferior vena cava diameter measurements. This is an observational cohort study that evaluated the correspondence between bioimpedance‐measured overhydration percentage (OH%) and BNP. We measured predialysis OH% by bioimpedance apparatus (Body Composition Monitor) and BNP by microparticle enzyme‐linked immunoassay in 41 prevalent stable hemodialysis patients, 19 (46%) women, aged 58.9 ± 14.5 years. The cohort's average BNP was 2694 ± 3278 pg/mL and 10 (24.4%) of these 41 patients had BNP < 500 pg/mL (average 260.7 ± 108.5). The OH% was 8.5 ± 7.0% among those with a BNP < 500 pg/mL, while the rest of the population had an OH% of 21.4 ± 8.0%, corresponding to excess volumes of 1.6 ± 1.3 and 4.4 ± 3.8 L, respectively. The OH% vs. BNP relationship was best described by the exponential regression of y = 216.4e0.097x, predicting a BNP of 216.4 pg/mL at 0% overhydration status (r 0.61). Receiver‐operating curves revealed an area under the curve of 0.885 for BNP when the OH% was set ≥15% of overhydration and an area under the curve of 0.918 for OH% when the BNP was set ≥500 pg/mL for being abnormal. We conclude that in our cohort there was a high degree of correspondence between these two tests with an exponential relationship between the measurements. 相似文献