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51.
Effect of vacuum‐drying,hot air‐drying and freeze‐drying on polyphenols and antioxidant capacity of lemon (Citrus limon) pomace aqueous extracts
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Konstantinos Papoutsis Penta Pristijono John B. Golding Costas E. Stathopoulos Michael C. Bowyer Christopher J. Scarlett Quan V. Vuong 《International Journal of Food Science & Technology》2017,52(4):880-887
The aim of this study was to investigate the effect of freeze‐drying, hot air‐drying and vacuum‐drying at 70, 90 and 110 °C, on dried lemon pomace polyphenols and antioxidant capacity. The total phenolic content and antioxidant capacity were higher in lemon pomace dried by hot air or under vacuum than those dried by freeze‐drying and increased as the temperature increased. The highest total flavonoid content was recorded in the pomace dried under vacuum at 70 and 90 °C. Lemon pomace dried by freeze‐drying had the highest neohesperidin content, whereas pomace dried under vacuum at 70 °C had the highest rutin and p‐coumaric acid content. The highest gallic acid content was recorded in the pomace dried by hot air at 110 °C. The results of this study indicate that drying technique should be carefully selected according to the bioactive compounds aimed to be extracted. 相似文献
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53.
Konstantinos Stavropoulos 《电信网技术》2014,(1)
正1引言时至今日,移动用户对他们手中终端的性能要求越来越高,特别是那些目前已经广泛使用的智能终端。如果不能满足这些期望和要求,用户很可能感到失望并减少使用手中的终端进行通信业务,甚至考虑更换可以提供更优质终端的移动运营商。这就是移动运营商为何现在如此关注并且投入大量人力物力在终端的品质验证上。 相似文献
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Konstantinos B. Baltzis John N. Sahalos 《Electrical Engineering (Archiv fur Elektrotechnik)》2009,91(4-5):211-219
In this paper, we propose a three-dimensional geometrically based stochastic model for the study of co-channel interference in cellular mobile systems. Exact analytical expressions for the statistics of the angle-of-arrival (AoA) of the interfering signals at the base station and the outage performance of a cellular network are derived. Simulated results show the merits of our proposal compared to the two-dimensional approach. The uplink AoA distribution statistics are examined in relation to cell size, antennas’ height and frequency reuse factor. Furthermore, the impact of base station antenna radiation pattern, beam tilting and cell sectorization on system performance is investigated. 相似文献
56.
Athena Roumboutsos Konstantinos P. Anagnostopoulos 《Construction Management & Economics》2013,31(7):751-763
Project participants, through experience, have an initial perception and predisposition towards risk and the types of risks they are willing and able to undertake. This is equally true for parties interested in public–private partnership (PPP) projects. These initial positions have been registered for the major Greek PPP market stakeholders potentially involved in a PPP arrangement through a survey covering all candidate construction companies, interested financing institutes and a number of public sector entities to be involved in PPPs. Findings revealed that stakeholders were, for the majority of risks identified, in agreement as to preferred risk allocation. Risk allocation preferences for construction companies were compared with similar findings for the UK, a mature PPP market, indicating a possible learning/maturing process based on the particular country background. Conclusions add to other surveys carried out on the subject and should enable public sector clients to establish a more efficient framework for risk allocation, thus reducing negotiations prior to contract award and minimizing the risk of poor risk distribution. 相似文献
57.
Structure–properties investigations in hydrophilic nanocomposites based on polyurethane/poly(2–hydroxyethyl methacrylate) semi‐interpenetrating polymer networks and nanofiller densil for biomedical application
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Panagiotis Klonos Vasileia Chatzidogiannaki Konstantinos Roumpos Ellas Spyratou Panayiotis Georgiopoulos Evagelia Kontou Polycarpos Pissis Yuriy Gomza Stanislav Nesin Oksana Bondaruk Lyudmyla Karabanova 《应用聚合物科学杂志》2016,133(11)
Nanocomposites based on sequential semi–interpenetrating polymer networks (semi–IPNs) of crosslinked polyurethane and linear poly(2‐hydroxyethyl methacrylate) filled with 1–15 wt % of nanofiller densil were prepared and investigated. Nanofiller densil used in an attempt to control the microphase separation of the polymer matrix by polymer–filler interactions. The morphology (SAXS, AFM), mechanical properties (stress–strain), thermal transitions (DSC) and polymer dynamics (DRS, TSDC) of the nanocomposites were investigated. Special attention has been paid to the raising of the hydration properties and the dynamics of water molecules in the nanocomposites in the perspective of biomedical applications. Nanoparticles were found to aggregate partially for higher than 3 and 5 wt % filler loading in semi–IPNs with 17 and 37 wt % PHEMA, respectively. The results show that the good hydration properties of the semi–IPN matrix are preserved in the nanocomposites, which in combination with results of thermal and dielectric techniques revealed also the existence of polymer–polymer and polymer–filler interactions. These interactions results also in the improvement of physical and mechanical properties of the nanocomposites in compare with the neat matrix. The improvement of mechanical properties in combination with hydrophilicity and biocompatibility of nanocomposites are promising for use these materials for biomedical application namely as surgical films for wound treatment and as material for producing the medical devises. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43122. 相似文献
58.
Panagiotis Theofilis Marios Sagris Evangelos Oikonomou Alexios S. Antonopoulos Konstantinos Tsioufis Dimitris Tousoulis 《International journal of molecular sciences》2022,23(6)
Platelets are at the forefront of human health and disease following the advances in their research presented in past decades. Platelet activation, their most crucial function, although beneficial in the case of vascular injury, may represent the initial step for thrombotic complications characterizing various pathologic states, primarily atherosclerotic cardiovascular diseases. In this review, we initially summarize the structural and functional characteristics of platelets. Next, we focus on the process of platelet activation and its associated factors, indicating the potential molecular mechanisms involving inflammation, endothelial dysfunction, and miRs. Finally, an overview of the available antiplatelet agents is being portrayed, together with agents possessing off-set platelet-inhibitory actions, while an extensive presentation of drugs under investigation is being given. 相似文献
59.
Angeliki Gardikioti Theodora-Maria Venou Eleni Gavriilaki Evangelia Vetsiou Ioulia Mavrikou Konstantinos Dinas Angelos Daniilidis Efthymia Vlachaki 《International journal of molecular sciences》2022,23(7)
Preeclampsia (PE) constitutes one of the principal reasons for maternal and perinatal morbidity and mortality worldwide. The circumstance typically implicates formerly healthful normotensive women, after 20 weeks of gestation, typically withinside the third trimester, without regarded threat elements or past deliveries. PE can be further complicated with hemolysis and thrombocytopenia, leading to the emergence of HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low platelets). Both conditions are classified as hypertensive diseases of pregnancy (HDP), and their pathogenesis has been linked to an excessive maternal inflammatory response, accompanied by enhanced endothelial activation. Several studies have found that in pregnancies affected by PE/HELLP, von Willebrand factor (vWF) antigen levels (vWF:Ag) are significantly elevated, while its cleaving protease (ADAMTS-13, A Disintegrin-like and Metalloprotease with Thrombospondin type 1 motif, member 13) activity is normal to decreased. Furthermore, the higher urine excretion of the terminal complement complex C5b-9, as well as its greater deposition in the placental surface in preeclamptic women, imply that the utero-placental unit’s distinctive deficits are intimately tied to disproportionate complement activation. The goal of this updated evaluation is to provide the most up-to-date molecular advances in the pathophysiology of PE/HELLP syndromes. Recent medical data on vWF:Ag levels in patients with PE, ADAMTS-13, and dysregulation of the complement system, are highlighted and evaluated. Furthermore, we discuss the relationship between those entities and the progression of the disease, as well as their significance in the diagnostic process. Finally, considering the difficulties in analyzing and controlling those symptoms in pregnant women, we can provide a current diagnostic and therapeutic algorithm. 相似文献
60.
An advanced centrifugal technique was developed to characterize the stickiness of tomato pulp at various moisture contents and temperatures. To provide tomato pulp samples with different moisture contents, tomato powder produced by a laboratory spray dryer was wetted to six different moisture levels. By noting the rotational speed for a tomato pulp droplet detachment and weighing the mass of the droplet remaining on the surface it is possible to gauge the approximate attachment forces holding the droplet to the substrate. The effects of droplet mass and centrifugation time after reaching the desired rotor speed on the detachment rate were also studied. The detachment force was found to increase at the beginning and then started decreasing as the moisture content decreased presenting a maximum at moisture content of about 34%. In addition, the higher the droplet temperature, the higher the attachment force. 相似文献