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排序方式: 共有1137条查询结果,搜索用时 15 毫秒
81.
Jan Bilski Agnieszka Irena Mazur-Bialy Marcin Surmiak Magdalena Hubalewska-Mazgaj Janusz Pokorski Jacek Nitecki Ewa Nitecka Joanna Pokorska Aneta Targosz Agata Ptak-Belowska Jerzy A. Zoladz Tomasz Brzozowski 《International journal of molecular sciences》2020,21(22)
Physical exercise is known to influence hormonal mediators of appetite, but the effect of short-term maximal intensity exercise on plasma levels of appetite hormones and cytokines has been little studied. We investigated the effect of a 30 s Wingate Test, followed by a postprandial period, on appetite sensations, food intake, and appetite hormones. Twenty-six physically active young males rated their subjective feelings of hunger, prospective food consumption, and fatigue on visual analogue scales at baseline, after exercise was completed, and during the postprandial period. Blood samples were obtained for the measurement of nesfatin-1, ghrelin, leptin, insulin, pancreatic polypeptide (PP), human growth factor (hGH) and cytokine interleukin-6 (IL-6), irisin and plasma lactate concentrations, at 30 min before exercise, immediately (210 s) after exercise, and 30 min following a meal and at corresponding times in control sedentary males without ad libitum meal intake, respectively. Appetite perceptions and food intake were decreased in response to exercise. Plasma levels of irisin, IL-6, lactate, nesfatin-1 and ghrelin was increased after exercise and then it was returned to postprandial/control period in both groups. A significant rise in plasma insulin, hGH and PP levels after exercise was observed while meal intake potentiated this response. In conclusion, an acute short-term fatiguing exercise can transiently suppress hunger sensations and food intake in humans. We postulate that this physiological response involves exercise-induced alterations in plasma hormones and the release of myokines such as irisin and IL-6, and supports the notion of existence of the skeletal muscle–brain–gut axis. Nevertheless, the detailed relationship between acute exercise releasing myokines, appetite sensations and impairment of this axis leading to several diseases should be further examined. 相似文献
82.
Anna Mroczek Joanna Zawitkowska Jerzy Kowalczyk Monika Lejman 《International journal of molecular sciences》2021,22(2)
Acute lymphoblastic leukaemia (ALL) is a relevant form of childhood neoplasm, as it accounts for over 80% of all leukaemia cases. T-cell ALL constitutes a genetically heterogeneous cancer derived from T-lymphoid progenitors. The diagnosis of T-ALL is based on morphologic, immunophenotypic, cytogenetic, and molecular features, thus the results are used for patient stratification. Due to the expression of surface and intracellular antigens, several subtypes of T-ALL can be distinguished. Although the aetiology of T-ALL remains unclear, a wide spectrum of rearrangements and mutations affecting crucial signalling pathways has been described so far. Due to intensive chemotherapy regimens and supportive care, overall cure rates of more than 80% in paediatric T-ALL patients have been accomplished. However, improved knowledge of the mechanisms of relapse, drug resistance, and determination of risk factors are crucial for patients in the high-risk group. Even though some residual disease studies have allowed the optimization of therapy, the identification of novel diagnostic and prognostic markers is required to individualize therapy. The following review summarizes our current knowledge about genetic abnormalities in paediatric patients with T-ALL. As molecular biology techniques provide insights into the biology of cancer, our study focuses on new potential therapeutic targets and predictive factors which may improve the outcome of young patients with T-ALL. 相似文献
83.
Tomasz Pawlak Antoni Ryniecki Jerzy Stangierski Idzi Siatkowski Barbara Peplińska 《Drying Technology》2019,37(2):156-163
Tenderization based on papain and microwave vacuum drying and puffing (MVDP) as well as adequate processing conditions enabled expansion of slices of the raw meat tissue. The main aim of the study was to use the response surface method and find the conditions of puffing that could maximize the expansion of meat during MVDP. The bound was set on the expansion: the most expanded puffings should be of good quality, including a desirable porous structure. The best combination of values of the MVDP process conditions (e.g., the initial moisture content in meat slices, microwave energy, and the vacuum absolute pressure) was found during experiments using the central composite design. The volume of slices puffed under these conditions was 1.60–1.78 times greater than the volume of slices before MVDP, and the sensory quality index remained acceptable. The research showed that pretreatment reduced the hardness of sample by over 25% and increased its crispiness, which was confirmed in cryo-scanning electron microscopy images. 相似文献
84.
Maria Leżańska Andrzej Olejniczak Jerzy P. Łukaszewicz 《Journal of Porous Materials》2018,25(6):1633-1648
Nitrogen-containing mesoporous carbons with the use of colloidal silica spheres of (14 nm) and chitosan as a carbon precursor were obtained. A removal of such small template particles from carbonized silica–chitosan composite is difficult and HF with a minimum concentration of 15 wt% should be used. By varying the silica-to-chitosan ratio, the porous characteristic of products is controlled. The modification by ZnCl2 with a molar Zn-to-C (in chitosan mass) ratio of ‘6’ results in the development of microporosity; however it is accompanied by a significant reduction of mesopore volume (Vmes). The addition of ZnCl2 in a ratio of ‘5.25’ and pH adjustment to 5.8 increase the volumes of micropores, small mesopores, BET surface area to 1975 m2/g, and preserve Vmes of 4.15 cm3/g. The novelty of the presented strategy is the creation of microporosity in the hard-templated materials by incorporating ZnCl2 into the mixture of Ludox HS-40 template and chitosan precursor, as well as the investigation on how the pH of synthesis influences the final porosity. The pH of a silica–chitosan–zinc solution, equal to 3.9, provides some coordination of Zn2+ by –OH and –NH2 groups, whereas pH adjustment to 5.8 results in the precipitation of a new template—Zn(OH)2. 相似文献
85.
Elisabeth Altmaier Gabi Kastenmüller Werner Römisch‐Margl Barbara Thorand Klaus M. Weinberger Jerzy Adamski Thomas Illig Angela Döring Karsten Suhre 《Molecular nutrition & food research》2009,53(11):1357-1365
The effect of coffee consumption on human health is still discussed controversially. Here, we report results from a metabolomics study of coffee consumption, where we measured 363 metabolites in blood serum of 284 male participants of the Cooperative Health Research in the Region of Augsburg study population, aged between 55 and 79 years. A statistical analysis of the association of metabolite concentrations and the number of cups of coffee consumed per day showed that coffee intake is positively associated with two classes of sphingomyelins, one containing a hydroxy‐group (SM(OH)) and the other having an additional carboxy‐group (SM(OH,COOH)). In contrast, long‐ and medium‐chain acylcarnitines were found to decrease with increasing coffee consumption. It is noteworthy that the concentration of total cholesterol also rises with an increased coffee intake in this study group. The association observed here between these hydroxylated and carboxylated sphingolipid species and coffee intake may be induced by changes in the cholesterol levels. Alternatively, these molecules may act as scavengers of oxidative species, which decrease with higher coffee intake. In summary, we demonstrate strong positive associations between coffee consumption and two classes of sphingomyelins and a negative association between coffee consumption and long‐ and medium‐chain acylcarnitines. 相似文献
86.
Dubis Eligiusz Poplawski Janusz Wróbel Jerzy T. Kúsmierz Józef Maliński Edmund Szafranek Janusz 《Lipids》1986,21(7):434-439
The exoskeleton triglyceride fraction isolated from the Colorado beetle,Leptinotarsa decemlineata Say, was studied. Analysis of the hydrolysis products and direct capillary column gas chromatography showed that, apart from
triglycerides, the fraction contained no diol lipids. The composition of the natural triacylglccerol mixture was assessed
by gas chromatography and by field desorption and electron impact mass spectrometry. Triglycerides isolated from the Colorado
beetle are typical glycerol triesters, with long chain (mainly oleic or palmitic) fatty acids. The structures of two major
components (91%), i.e., trioleoyl glycerol and 1,2-dioleoyl-3-palmitoyl glycerol, were determined. 相似文献
87.
88.
Amorphous computing differs from the classical ideas about computations almost in every aspect. The architecture of amorphous
computers is random, since they consist of a plethora of identical computational units spread randomly over a given area.
Within a limited radius the units can communicate wirelessly with their neighbors via a single-channel radio. We consider
a model whose assumptions on the underlying computing and communication abilities are among the weakest possible: all computational
units are finite state probabilistic automata working asynchronously, there is no broadcasting collision detection mechanism
and no network addresses. We show that under reasonable probabilistic assumptions such amorphous computing systems can possess
universal computing power with a high probability. The underlying theory makes use of properties of random graphs and that
of probabilistic analysis of algorithms. To the best of our knowledge this is the first result showing the universality of
such computing systems.
This research was carried out within the institutional research plan AV0Z10300504 and partially supported by the GA ČR grant
No. 1ET100300517 and GD201/05/H014. A preliminary, shorter version of this paper has been presented at the Third Conference
on Computability in Europe, CiE 2007, Siena, Italy, June 2007 and published in the proceedings from this conference. 相似文献
89.
Jerzy Ratajski 《Surface & coatings technology》2009,203(16):2300-2306
The present work is devoted to an investigation of the influence of the micro-structural evolution of the compound zone (iron (carbo)nitrides zone) upon the development of hardness profiles in the diffusion zone. A different phase structure of iron (carbo)nitrides zone on steel as compared to iron, further changing with the process, may result in upsetting of the quasi-equilibrium of nitrogen concentration in the iron (carbo)nitrides zone/diffusion zone interface. This, as a result, may have an impact on the kinetics of this layer's growth. The research carried out was aimed at solving this problem. It was to evaluate the influence of (carbo)nitrides zone, with an intentionally created diametrically different phase composition, on hardness profiles in the diffusion zone. The nitrided layers were characterised by a light optical microscopy, X-ray diffraction and measurements of hardness. It was observed that the evolution of the phase structure and phase composition of the compound zone contributes significantly, regardless of nitrogen potential and temperature, to the formation of the diffusion zone and in particular to its effective thickness. It makes this complex picture of nitrided case development on steel even more intricate. 相似文献
90.
The experimental material was a myofibrillar preparation obtained from mechanically recovered poultry meat by the washing
and separation of fat and connective tissues. Changes occurring during frozen storage were investigated in the preparation
without and with the addition of the following substances: 2 g/kg carrageen, 2.5 g/kg sodium tripolyphosphate (TPP) mixture
and 80 g/kg polydextrose, and 3 g/kg enzymatic preparation (ACTIVA WM) containing microbial transglutaminase (MTG). Samples
with the addition of MTG were pre-incubated at the temperature of 7 ± 1 °C for 1, 3, 5, 24 h. All samples were stored at the
temperature of approx. −23 °C for 2, 30, 60, 90 days. The smallest change in protein solubility was observed in samples with
added TPP and polydextrose. Along with the extension of pre-incubation time of samples containing the enzyme a gradual decrease
was found in the amount of soluble protein. Also the results of the investigations obtained using the DSC technique showed
the most advantageous protective effect, i.e., causing the smallest decrease in enthalpy values of samples during freezer
storage, in case of the addition of TPP and polydextrose mixture. Analysis of thermal drip volume from gels showed that carrageen
was the most advantageous addition to the myofibrillar preparation. Moreover, a gradual increase was observed in the volume
of thermal drip along with the extension of pre-incubation time of the protein isolate with enzymatic preparation. Results
of gel texture testing indicated that the most advantageous effect on gel quality was found for ACTIVA applied in 3 and 5 h
pre-incubation with the myofibrils. Assuming that among the analyzed properties the most important were thermal drip and gel
texture, 3 g/kg MTG at pre-incubation time of 3 h was considered the most advantageous additive. 相似文献