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991.
The main goal of the present work was to compare and correlate the results of physicochemical parameters and antiradical performance of some oil blends during deep‐frying, which will be an initial indicator for applying antiradical tests for monitoring deep‐frying oils. Two oil blends were prepared. The first blend was a mixture (1 : 1, wt/wt) of sunflower seed oil and palm olein (SO/PO) and the second was a mixture (1 : 1, wt/wt) of cottonseed oil and palm olein (CO/PO). The oil blends were evaluated during intermittent frying of French fries on two consecutive days for 16 h, with oil replenishing after 8 h. Changes in the fatty acid profile and some physicochemical parameters (peroxide value, color index, viscosity, total polar compounds and UV absorbance at 232 and 270 nm) were used to evaluate the alterations during frying. A quick spectrophotometric method was developed to assess deep‐frying oil quality. With the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) method, the neutralization of the stable radical DPPH by antioxidants present in the oil during frying was measured. Radical‐scavenging activity (RSA) of both oil blends was recorded during frying, wherein the results showed that the SO/PO blend had the highest RSA. It was evident from the results that a proportional correlation and positive relationship existed between the levels of fatty acids and the physicochemical characteristics of the vegetable oil blends and their RSA. The initial results obtained allow us to suggest that antiradical measurements could be used to quantify the oxidative and hydrolytic deterioration of vegetable oils upon frying.  相似文献   
992.
The mechanical behavior of 316LVM 1 × 7 cables were evaluated in uniaxial tension and in cyclic strain-controlled fatigue with the use of a Flex tester operated to provide fully reversed bending fatigue. The magnitude of cyclic strains imparted to each cable tested was controlled via the use of different diameter mandrels. Smaller diameter mandrels produced higher values of cyclic strain and lower fatigue life. Multiple samples were tested and analyzed via scanning electron microscopy. The fatigue results were analyzed via a Coffin–Manson–Basquin approach and compared to fatigue data obtained from the literature where testing was conducted on similar materials, but under rotating bending fatigue conditions.  相似文献   
993.
Alpha-feto-protein (AFP) is the most popular tumor marker for hepatocellular carcinoma (HCC). It is used in diagnosis and follow up of cases by estimating its rise in the serum. The aim of this work is to study the value of estimating AFP in ascitic fluid of HCC patients with ascites. This work is a case control study on 32 patients, including 22 cases with ascites and HCC and 10 control group with ascites due to liver cirrhosis without HCC. The level of AFP was estimated in serum and in ascitic fluid by Radio-immuno assay RIA. The serum ascites albumin gradient (SAAG) was assessed by measuring albumin in all samples using bromocresole green dye binding. Guided aspiration liver biopsy and ascitic fluid cytology was done, stained with H & E. It was found that, AFP level in serum was elevated in 72.7% of HCC patients, and in ascitic fluid was elevated 63.6% HCC patients. Also, there was a highly significant, direct positive correlation between elevation of AFP in serum and in ascitic fluid (r = 0.778). No elevation of AFP in serum and in ascitic fluid was detected in control group. Ascitic fluid cytology showed malignant cells in one case only. SAAG was significantly lower in the HCC group 0.83 gm/dl than the control group 2.43 gm/dl (p-value < 0.001). Elevation of AFP in ascitic fluid is of high importance in evaluation of HCC, and is as significant as serum and runs parallel to it. Estimation of AFP in ascitic fluid is much more significant in evaluation of HCC cases than ascitic fluid cytology.  相似文献   
994.
Compaction grouting is an important soil improvement and underpinning technique that involves injection of a very stiff grout material into the soil. The objective is to displace and compact the surrounding soil without permeating or hydrofracturing it. Compaction grouting has been developed and used almost entirely on the basis of practical experience. The present study proposes a theoretical model that describes the mechanics of the compaction grouting process and rationally considers the different soil and grouting parameters that govern the overall design and performance of the method. The theoretical basis of the model draws from the theory of cavity expansion as well as the conical shear failure above the grout bulb. This model was validated using limited available data. The results indicate reasonable agreement and show a good potential of the proposed model for rationally optimizing the design of compaction grouting operations.  相似文献   
995.
Recently nanomaterials have attracted interest for increasing efficiency of polymerase chain reaction (PCR) systems. Here, the authors report on the usefulness of green graphene oxide/gold (GO/Au) nanocomposites for enhancement of PCR reactions. In this study, green GO/Au nanocomposite was prepared with Matricaria chamomilla extract as reducing/capping agent for site‐directed nucleation of Auo atoms on surface of GO sheets. The as‐prepared green GO/Au nanocomposites were then characterised with UV–VIS spectrophotometer and scanning electron microscopy. Later, the effect of these nanocomposites was studied on end‐point and real‐time PCR employed for amplification of human glyceraldehyde‐3‐phosphate dehydrogenase gene. The results indicated that GO/Au nanocomposite can improve both end‐point and real‐time PCR methods at the optimum concentrations, possibly through interaction between GO/Au nanocomposite and the materials in PCR reaction, and through providing increased thermal convection by the GO surface as well as the Au nanostructures. In conclusion, it can be suggested that green GO/Au nanocomposite is a biocompatible and eco‐friendly candidate as enhancer of in‐vitro molecular amplification strategies.Inspec keywords: graphene, molecular biophysics, nucleation, enzymes, gold, nanofabrication, nanocomposites, scanning electron microscopy, nanoparticles, DNA, nanomedicine, ultraviolet spectra, visible spectra, graphene compoundsOther keywords: green GO/Au nanocomposite, polymerase chain reaction systems, green graphene oxide/gold, PCR reaction, as‐prepared green GO/Au nanocomposites, real‐time PCR methods, Au nanostructures, in‐vitro amplification, human DNA, Matricaria chamomilla extract, site‐directed nucleation, Au, CO, CO‐Au  相似文献   
996.
Primary chemically formed lead dioxide (PbO2) was used as positive electrode in preparation of lead–acid bipolar batteries. Chemical oxidation was carried out by both mixing and dipping methods using an optimized amount of ammonium persulfate as a suitable oxidizing agent. X-ray diffraction studies showed that the weight ratio of β-PbO2 to α-PbO2 is more for mixing method before electrochemical forming. The electrochemical impedance spectroscopy (EIS) was used to investigate charge transfer resistance of the lead dioxide obtained by mixing and dipping methods before and after electrochemical forming. Four types of bipolar lead–acid batteries were produced with: (1) lead substrate and conventional electroforming; (2) carbon doped polyethylene substrate with conventional electroforming; (3) carbon doped polyethylene substrate with chemical forming after curing and drying steps in oxidant bath, followed by electrochemical forming, and (4) carbon doped polyethylene substrate with primary chemical oxidation in mixing step, followed by conventional electroforming. The capacity and cycle-life tests of the prepared bipolar batteries were performed by a home-made battery tester and using the pulsed current method. The prepared batteries showed low weight, high capacity, high energy density and high power density. The first capacities of bipolar batteries of type 1–4 were found to be 152, 150, 180 and 198 mAh g−1, respectively. The experimental results showed that the prepared 6 V bipolar batteries of type 1–4 have power density (per cell unit) of 59.7, 57.4, 78.46 and 83.30 mW g−1 (W kg−1), respectively.  相似文献   
997.
The distribution patterns of methylhomologs of naphthalene and phenanthrene in five crude oils from the southern part of the Gulf of Suez, Egypt, have been examined by quantitative capillary gas chromatography (GC) and computerized gas chromatography/mass spectrometry (GC/MS). In general, the relative abundance of individual naphthalenes and phenanthrenes were not significantly different in the five oil samples. Correlation between the source rock deposition and the abundance of specific methylnaphthalene and melhylphenanthrene isomers are consistent with a marine type source materials for the analyzed Gulf of Suez oils. Maturity parameters based on methylnaphthalene and methylphenanthrene isomers were almost identical and are consistent with an advanced stage of maturity. Further, calculated vitrinite reflectance (Re) confirmed that the sediments have a range of maturity within the “oil window”.  相似文献   
998.
Effect of some important parameters on low-velocity impact response of the active thin-walled hybrid composite plates embedded with the shape memory alloy (SMA) wires is investigated in this paper. The interaction between the impactor and the composite plate is considered in the impact analysis. The SMA wires are embedded within the layers of the composite laminate. The effect of the SMA wires on contact force history, deflection, in-plane strains and stresses of the structure was studied. The first-order shear deformation theory as well as the Fourier series method is utilized to solve the governing equations of the composite plate analytically. The interaction between the impactor and the plate is modeled with the help of two degrees-of-freedom system, consisting of springs-masses. The Choi's linearized Hertzian contact model is used in the impact analysis of the laminated hybrid composite plate. The results indicate that some of the important geometrical and physical parameters like the SMA volume fraction, orientation of composite medium fibers, impactor mass, impactor velocity, and length-to-thickness ratio of the plate (a/h ratio) are important factors affecting the impact process and the design of structures.  相似文献   
999.
Rheological and morphological properties of low‐density polyethylene (LDPE) and thermoplastic starch (TPS) with low‐density polyethylene‐grafted‐maleic anhydride as a compatibilizer were investigated. The results showed that the circularity of the droplets decreased with increasing TPS content. The presence of compatibilizer led to finer morphology and higher continuity. The rheological analyses showed that TPS and compatibilizer can increase elasticity and viscosity of the blend dramatically. In addition, the compatibilizer enhanced the compatibility of the blends, as evidenced by the shifting of the relaxation time peak of TPS to longer times. The rheological properties of the neat components and their blends were discussed by the Carreau‐Yasuda and fractional Zener models. The fractional Zener model results proved the existence of network structure in the compatibilized blends. The transient properties of blends showed that TPS and compatibilized blends had strong overshoot compared with the uncompatibilized blend, owing to the formation of high elastic network in their structure. J. VINYL ADDIT. TECHNOL., 20:250–259, 2014. © 2014 Society of Plastics Engineers  相似文献   
1000.
A series of 4-(substituted)-N-(guanidinyl)benzenesulfonamides bearing biologically active pyrazole, pyrimidine and pyridine moieties were prepared and evaluated for their anticancer activity against human tumor breast cell line (MCF7). These sulfonamides showed promising activity with IC50 values ranging from 49.5 to 70.2 μM. The structure-activity relationship of the synthesized compounds was studied. Interestingly, it was found that the most potent compounds in this study were the corresponding 2-cyanoacrylate 3, 3-oxobutanoate 4, pyrazole 6, pyridine 9 and pyrazole 13. Compounds 7 and 8 are nearly as active as Doxorubicin as reference drug with (IC50 values = 70.2, 68.1 μM), while compounds 5, 10 and 11 exhibited a moderate activity.  相似文献   
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