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101.
Dixiong Wang Michael B. Clark Jr Susan Trolier‐McKinstry 《Journal of the American Ceramic Society》2018,101(8):3443-3451
Low‐temperature processed bismuth niobate (BNO) thin films were explored in this work as a potential candidate for high‐energy density capacitors. The BNO samples were fabricated by the chemical solution deposition method followed by a series of ultraviolet (UV) exposure and heat treatments. A UV treatment prior to the final pyrolysis step was found to be useful in eliminating bound carbon. X‐ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS) demonstrated that the residual carbon could be effectively removed at 350°C after UV exposure. Following a heat treatment at 450°C, the energy storage density of the BNO thin film reached 39 J/cm3 with an efficiency of 72%. Furthermore, 350°C and 375°C treated BNO samples showed high‐temperature stability such that the efficiencies of the films remained above 97% up to 150°C at 10 kHz under 1 MV/cm applied field. 相似文献
102.
Susan Masten Brent Simpson Susan Hengemuehle Paramjeet Pati Alla Alpatova Boubacar Dembele 《臭氧:科学与工程》2015,37(1):29-35
Jatropha curcas is a well-known source of non-edible vegetable oil that is being promoted as an energy source and high quality feedstock in biodiesel production, especially in developing countries. The potential that the resulting seedcake by-product from jatropha oil extraction (?70% by volume) could also be used as a component in animal feed raises the prospect that a commercially viable jatropha-based industry could be developed. To date, however, the use of jatropha seedcake in livestock feed formulation has been constrained by the presence of phorbol esters (PE), which are known promutagenic and toxic compounds, and by the inability to eliminate PE by cost-effective means. Using seedcake by-product collected from a commercial facility in West Africa that processes jatropha biodiesel, this study demonstrates cost-effective measures of eliminating PE from jatropha seedcake using a combination of solar irradiation and ozonation. 相似文献
103.
Correlation between Physical Properties and Shear Adhesion Strength of Enzymatically Modified Soy Protein-Based Adhesives 下载免费PDF全文
Min Jung Kim Xiuzhi Susan Sun 《Journal of the American Oil Chemists' Society》2015,92(11-12):1689-1700
This work was to correlate physical properties with adhesion properties of soy protein‐based adhesives. By building such a correlation, the adhesion properties can be predicted by measuring physical properties of soy protein‐based adhesives. In this context, three important physical properties, viscosity, tacky force, and water resistance, were selected to correlate with adhesion strength of enzymatically modified soy protein‐based adhesives (ESP). Response surface methodology, specifically central composite design, was used with three independent variables to prepare ESP: trypsin concentration (X1), incubation time (X2), and glutaraldehyde (GA) concentration (X3). The three physical properties measured were all greatly affected by our three independent variables with significance at the 95 % confidence level. The responses were then correlated with the adhesion properties of ESP. In conclusion, viscosity can be used to predict the dry adhesion strength of ESP based on the coefficient of determination (R2) of 0.8558. In addition, tacky force and water resistance can be used to represent wet adhesion strength of ESP based on R2 of 0.7082 and 0.6930, respectively (P < 0.05). This work preliminarily identified the significant physical properties that can predict the adhesion strength of the ESP system crosslinked with GA, but the results need to be further confirmed by another protein modification system to give a generic conclusion. 相似文献
104.
Daniel M. Marincel Huairuo Zhang Stephen Jesse Alex Belianinov Mahmut B. Okatan Sergei V. Kalinin W. Mark Rainforth Ian M. Reaney Clive A. Randall Susan Trolier‐McKinstry 《Journal of the American Ceramic Society》2015,98(6):1848-1857
Domain wall movement at and near engineered 10°, 15°, and 24° tilt and 10° and 30° twist grain boundaries was measured by band excitation piezoresponse force microscopy for Pb(Zr,Ti)O3 films with Zr/Ti ratio of 45/55 and 52/48. A minimum in nonlinear response was observed at the grain boundary for the highest angle twist and tilt grain boundaries, while a maximum in nonlinear response was observed at the 10° tilt grain boundaries. The observed nonlinear response was correlated with the domain configurations imaged in cross section by transmission electron microscopy. 相似文献
105.
Plasticization effects of dihydroxyl soybean oil improve flexibilities of epoxy‐based films for coating applications 下载免费PDF全文
Novel bio‐based coating materials were developed through cationic ring‐opening photopolymerization of dihydroxyl soybean oil (DSO) with commercial epoxy monomers [i.e., epoxidized soybean oil (ESO) and 3,4‐epoxycyclohexylmethyl‐3,4‐epoxycyclohexanecarboxylate (ECHM). The ether cross‐linking and post‐polymerization of the polymeric network were observed using Fourier transform infrared spectroscopy. Thermal properties of the bio‐based coating materials and their copolymerization behaviors were examined using differential scanning calorimetry and a thermogravimetric analyzer. Cross‐link density and molecular weight between cross‐link were obtained from dynamic mechanical analysis. ECHM/DSO (1 : 1.43 weight ratio) films showed the highest elongation at break (49.2%) with a tensile strength of 13.7 MPa. After 2 months of storage, the elongation at break and tensile strength of films were 32% and 15.1 MPa, respectively. ESO/DSO films (w/w ratios of 1 : 0.1, 1 : 0.15, and 1 : 0.2) exhibited stable flexibility of 11–13% of elongation at break without significant reductions in tensile strength (2.5–4.4 MPa) during a 2‐month shelf life. Optical transparencies of the films were comparable to commercial glass and polymers, and water uptake properties (0.72% and 2.83%) were significantly low. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41773. 相似文献
106.
Teri Smith Susan Sharp Ann M. Manzardo Merlin G. Butler 《International journal of molecular sciences》2015,16(3):4416-4428
Advances made in genetic testing and tools applied to pharmacogenetics are increasingly being used to inform clinicians in fields such as oncology, hematology, diabetes (endocrinology), cardiology and expanding into psychiatry by examining the influences of genetics on drug efficacy and metabolism. We present a clinical case example of an adolescent male with anxiety, attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder who did not tolerate numerous medications and dosages over several years in attempts to manage his symptoms. Pharmacogenetics testing was performed and DNA results on this individual elucidated the potential pitfalls in medication use because of specific pharmacodynamic and pharmacokinetic differences specifically involving polymorphisms of genes in the cytochrome p450 enzyme system. Future studies and reports are needed to further illustrate and determine the type of individualized medicine approach required to treat individuals based on their specific gene patterns. Growing evidence supports this biological approach for standard of care in psychiatry. 相似文献
107.
Loss of fluorescence from cis-parinaric acid (cPnA) is a sensitive indicator of lipid peroxidation. The purpose of this study was to utilize cPnA to determine,
at the level of the intact immune cell, whether enrichment of membranes with polyunsaturated fatty acids (PUFA) increased
lipid peroxidation. P388D1 macrophages were labeled by addition of cPnA as an ethanolic solution. Within two minutes of addition,
in the absence of serum, cPnA rapidly intercalated into the plasma membrane. Lipid peroxidation was initiated by addition
of Fe2+-EDTA resulting in a dose-dependent decrease in fluorescence with increased oxidant concentration. Cells previously enriched
with PUFA and labeled by intercalation showed no differences in spontaneous or Fe2+-induced lipid peroxidation. In separate experiments, 20 μM cPnA in ethanolic solution was injected into cell culture media
containing 0.1% essentially fatty acid free bovine serum albumin (BSA). Cells were resuspended and incubated for 90 min at
37°C. After washing with BSA to remove cPnA which had not incorporated, 0.5% (0.1 μM) of the added cPnA was found esterified
within cellular lipids. This level of cPnA provided a 100-fold increase over basal autofluorescence levels. Cells labeled
in this manner also lost fluorescence in a dose-dependent manner as levels of oxidant stress increased. Cells enriched with
PUFA and labeled by esterification had significantly increased rates and total amounts of lipid peroxidation. Co-incubation
with α-tocopherol and PUFA resulted in a decrease in lipid peroxidation which was not significantly different from control
cells. In conclusion, esterification of cPnA into membrane phospholipids can sensitively detect changes in lipid peroxidation
induced by alteration of membrane PUFA and/or vitamin E content.
Presented in part at the Experimental Biology Meetings, Anaheim, California, April 1994.
Contribution from the Missouri Agriculture Extention Station, Journal #12,495. 相似文献
108.
Peter T. Witte Peter H. Berben Susan Boland Evert H. Boymans Dieter Vogt John W. Geus Johannes G. Donkervoort 《Topics in Catalysis》2012,55(7-10):505-511
An innovative BASF catalyst manufacturing technology (NanoSelect?) is introduced which allows production of heterogeneous catalysts with excellent control over metal crystallite sizes. NanoSelect? technology enabled the development of Pd catalysts which are lead-free Lindlar catalyst replacements in alkyne-to-cis-alkene hydrogenations. NanoSelect? Pt catalysts showed excellent chemoselectivity in substituted nitro-arene hydrogenation reactions without build-up of hydroxylamine intermediates. All NanoSelect? produced catalysts show markedly higher activity per gram of metal leading to ten-fold less use of precious metal. 相似文献
109.
Sung Wook Hwang Jin Kie Shim Susan EM Selke Herlinda Soto‐Valdez Laurent Matuana Maria Rubino Rafael Auras 《Polymer International》2012,61(3):418-425
Poly(L ‐lactic acid) (PLLA) films containing various concentrations of two natural antioxidants, α‐tocopherol and resveratrol, were fabricated by a melt compounding and compression molding process. The influence of the antioxidants on the optical properties such as color and UV‐visible light transmission was analyzed. The thermal, mechanical, rheological and physical properties of PLLA films with added antioxidants were assessed. PLLA films with added α‐tocopherol and resveratrol showed a yellowish brown color and the lightness was influenced by the presence of the antioxidants. The glass transition and melting temperatures were significantly reduced with the addition of antioxidants while enhanced thermal stability was observed, which could be a benefit and important for processing and production. PLLA films with added antioxidants were slightly more hydrophobic than neat PLLA. The combination effect of plasticizing and enhancement of the elastic modulus with differing concentrations of two antioxidants played a critical role in the mechanical and thermomechanical properties of PLLA films. The melt viscosity of the PLLA films with added antioxidants was substantially higher than that of neat PLLA. The higher melt viscosity and G′(ω) could be an indication of formation of entanglement between PLLA and the two antioxidants. Copyright © 2012 Society of Chemical Industry 相似文献
110.
Soini HA Linville SU Wiesler D Posto AL Williams DR Novotny MV 《Journal of chemical ecology》2012,38(2):145-156
We investigated head- and cheek-rubbing behavior in four species of large felines, lions (Leo panther), leopards (Panthera pardus), tigers (Panthera tigris), and cougars (Puma concolor), in captivity. Preliminary behavioral observations found that lions and tigers, but not leopards and cougars, showed behavioral
responses to cardboard rubbing samples from head and cheek areas from conspecific felines, compared to the blank cardboard
controls. In this context, surface samples on the facial areas of each species were collected to analyze volatile organic
compounds that could be involved in the facial marking of felines. Previously developed stir bar surface sampling methodology
was used. From all cheek and forehead samples, 100 volatile organic compounds were identified or tentatively identified. Among
these, 41 have been previously reported to be present in feline urine and marking secretions. Several new compounds were identified
on facial surfaces. Some of the compounds showed substantial quantitative differences among the species. One compound, that
has not been reported previously in mammals, 3-acetamidofuran, was found in all investigated species. It was synthesized and
tested for behavioral responses. No responses were elicited in a preliminary test. Future research will test other potential
signaling compounds and their mixtures for ability to elicit behavioral responses. 相似文献