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排序方式: 共有511条查询结果,搜索用时 15 毫秒
411.
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413.
Deniz Arslan Metin Gürü M. Kürşat Çubuk Meltem Çubuk 《Construction and Building Materials》2011,25(10):3863-3868
This study investigates the modification of bitumen with triethylene glycol based polyboron (TEGPB). TEGPB is a new additive material which was chemically synthesized at laboratory conditions. Four different TEGPB concentrations were used to modify 50/70 penetration grade bitumen: 1%(w/w), 2%(w/w), 3%(w/w) and 5%(w/w). The effects of TEGPB modification on the bitumen and bituminous mixture properties were determined by means of softening point, Marshall stability, Nicholson stripping, rotational viscosity (RV), Dynamic Shear Rheometer (DSR) and Bending Beam Rheometer (BBR) tests. Amount of TEGPB to be used within the bitumen has been chosen as 2%(w/w) according to RV test results. BBR and Nicholson stripping test results have showed that creep properties and stripping resistance of the modified bitumen was not adversely affected. It was also found out that softening point and rutting resistance of the bitumen as well as Marshall stability of the bituminous mixtures were increased by TEGPB modification. 相似文献
414.
The aim of the study is to determine the optimum cure temperatures and kinetics for two different epoxy resin systems without using solvent. Two resin systems consist of EPIKOTE 828® epoxy resin–EPIKURE® 3090 polyamidoamine curing agent and DURATEK® KLM 606A epoxy resin–DURATEK® KLM 606B polyamide curing agent. The ratio of resin to curing agent was kept as 1:1 for both the systems. Curing temperatures of both the systems were determined and kinetic parameters were calculated with respect to the experimental results following nth‐order kinetics. Then, a series of isothermal temperatures was applied to the resin systems in order to assess the cure process in terms of conversion, time, and temperature by using differential scanning calorimeter (DSC). The test results of both systems show that the rate of degree of cure for EPIKOTE 828® epoxy resin–EPIKURE® 3090 polyamidoamine curing agent system is approximately 10 times higher than that of DURATEK® KLM 606A epoxy resin–DURATEK® KLM 606B polyamide curing agent system at 230°C. POLYM. COMPOS., 28:762–770, 2007. © 2007 Society of Plastics Engineers 相似文献
415.
Alican Güran Yanlong Ji Pan Fang Kuan-Ting Pan Henning Urlaub Metin Avkiran Christof Lenz 《International journal of molecular sciences》2021,22(22)
β-adrenergic receptor (β-AR) stimulation represents a major mechanism of modulating cardiac output. In spite of its fundamental importance, its molecular basis on the level of cell signalling has not been characterised in detail yet. We employed mass spectrometry-based proteome and phosphoproteome analysis using SuperSILAC (spike-in stable isotope labelling by amino acids in cell culture) standardization to generate a comprehensive map of acute phosphoproteome changes in mice upon administration of isoprenaline (ISO), a synthetic β-AR agonist that targets both β1-AR and β2-AR subtypes. Our data describe 8597 quantitated phosphopeptides corresponding to 10,164 known and novel phospho-events from 2975 proteins. In total, 197 of these phospho-events showed significantly altered phosphorylation, indicating an intricate signalling network activated in response to β-AR stimulation. In addition, we unexpectedly detected significant cardiac expression and ISO-induced fragmentation of junctophilin-1, a junctophilin isoform hitherto only thought to be expressed in skeletal muscle. Data are available via ProteomeXchange with identifier PXD025569. 相似文献
416.
The α-Discounting Method was developed to be an alternative to and extension of the Analytical Hierarchy Process (AHP) to solve multi-criteria decision-making (MCDM) problems with non-commensurable and conflicting criteria. In contrast to the AHP, this method works not only for pairwise comparisons but also for n-wise comparisons if relative importance of criteria can be expressed in a system of linear homogenous equations. This method also has a comparative advantage as it can transform those MCDM problems, classified as inconsistent by the AHP, into a consistent form. This study briefly compares the two methods and then develops the Fuzzy α-Discounting Method for Multi-Criteria Decision Making (Fα-DM MCDM). Two illustrative fuzzy MCDM problems from the literature have been solved to show how the Fα-DM MCDM works. 相似文献
417.
418.
Umut T. Sanli Hakan Ceylan Iuliia Bykova Markus Weigand Metin Sitti Gisela Schütz Kahraman Keskinbora 《Advanced materials (Deerfield Beach, Fla.)》2018,30(36)
High‐performance focusing of X‐rays requires the realization of very challenging 3D geometries with nanoscale features, sub‐millimeter‐scale apertures, and high aspect ratios. A particularly difficult structure is the profile of an ideal zone plate called a kinoform, which is manufactured in nonideal approximated patterns, nonetheless requires complicated multistep fabrication processes. Here, 3D fabrication of high‐performance kinoforms with unprecedented aspect ratios out of low‐loss plastics using femtosecond two‐photon 3D nanoprinting is presented. A thorough characterization of the 3D‐printed kinoforms using direct soft X‐ray imaging and ptychography demonstrates superior performance with an efficiency reaching up to 20%. An extended concept is proposed for on‐chip integration of various X‐ray optics toward high‐fidelity control of X‐ray wavefronts and ultimate efficiencies even for harder X‐rays. Initial results establish new, advanced focusing optics for both synchrotron and laboratory sources for a large variety of X‐ray techniques and applications ranging from materials science to medicine. 相似文献
419.
Metin Arslan 《Korean Journal of Chemical Engineering》2010,27(3):991-998
Poly(ethylene terephthalate) (PET) fibers were grafted with acrylamide (AAm) and 2-hydroxyethylmethacrylate (HEMA) using benzoyl
peroxide (Bz2O2) as initiator in aqueous media. PET fibers were swelled in dichloroethane (DCE) for 2 h at 90 °C to promote the incorporation
and the subsequent polymerization of AAm/HEMA onto PET fibers. Variations of graft yield with time, temperature, initiator
concentration and monomer mixture ratio were investigated. The optimum initiator concentration was found to be 10 mmol/L.
The maximum graft yield was obtained (prep.) 273%. The optimum temperature and polymerization time were found to be 85 °C
and 120 min, respectively. The rate of grafting was found to be proportional of the 1.39 and 0.37 powers of AAm/HEMA and Bz2O2 concentrations, respectively. The grafted PET fibers were characterized by FTIR spectroscopy and scanning electron microscopy
(SEM). Further changes in properties of grafted PET fibers such as water absorption capacity and diameter were determined.
The dyeability of the PET fibers increased with an increase in grafting with acidic and basic dyes. 相似文献
420.
Summary Poly(ethylene terephthalate) (PET) fibers were grafted with 4-vinyl pyridine (4-VP) and 2-hydroxyethylmethacrylate (HEMA)
using benzoyl peroxide (Bz2O2) as initiator in aqueous media. PET fibers were swelled in dichloroethane (DCE) for 2 h at 90 °C to promote the incorporation
and the subsequent polymerization of 4-VP/HEMA onto PET fibers. Variations of graft yield with time, temperature, initiator
concentration and monomer mixture ratio were investigated. The optimum initiator concentration was found to be 8×10-3 mol/L. The maximum graft yield was obtained 280%. The optimum temperature and polymerization time was found to be 85 °C and
100 min. respectively. The rate of grafting was found to be proportional of the 1.5 and 0.3 powers of 4-VP/HEMA and Bz2O2 concentrations, respectively. The grafted PET fibers were characterized by thermo gravimetric analysis and scanning electron
microscopy (SEM). Further changes in properties of grafted PET fibers such as water absorption capacity, intrinsic viscosity
and diameter were determined. The dye ability of the PET fibers increased with an increase in grafting with diazo and basic
dyes. 相似文献