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81.
Described herein is a case study of long-term reverse osmosis (RO) plant operation without applying chemical pretreatments to the feed water. This project was undertaken with the financial support from the Department of Bio-Technology, New Delhi, and the work was carried out by a research team from Central Salt and Marine Chemicals Research Institute (CSMCRI), Bhavnagar (Gujarat), India. A prototype plant with a 30,000 L/d capacity was designed, manufactured, installed and operated at the village of Mocha-Gorsar, located in the Porbandar district, to provide drinking water. The village was to be developed as a model Bio-Village where other projects related to village problems are also operated by other research institutes. Thin-film composite (TFC) membrane-based RO technology was indigenously developed by the institute for treatment of brackish water and waste water for the first time in India; it was used successfully in this plant, which gave a typical NaCl rejection of about 95%. This is a typical case study of RO plant installation where physical methods of pretreatment such as sand and micron cartridge filters were used; no chemical pretreatment of feed was employed for long-term brackish water desalination study. The idea was to avoid the usage of chemicals, which concentrate in the effluent water, might affect the environment and may not suit the village community. Plant performance during 24 months of continuous operation with respect to variable feed salinity, membrane cleaning and regenerations is discussed.  相似文献   
82.
Layered Li[Li0.12NizMg0.32−zMn0.56]O2 oxide cathodes containing lithium atoms in the transition metal layers were synthesized and characterized using X-ray diffraction (XRD), galvanostatic cycling, and differential scanning calorimetry (DSC). The Li[Li0.12NizMg0.32−zMn0.56]O2 cathodes deliver a specific discharge capacity of about 190 mAh/g at room temperature and 236 mAh/g at 55 °C when cycled between 2.7 and 4.6 V versus Li/Li+. Excellent capacity retention and smooth potential profiles at room and elevated temperatures over extended cycles suggest that this material does not convert into a spinel structure.  相似文献   
83.
84.
We successfully prepared La1?xBixFeO3 (LxB1?xFO, x?=?0.01–0.1) nanoparticles using a sol-gel technique, and studied their photocatalytic, magnetic, and electrochemical properties. Structural refinement studies of the prepared nanoparticles revealed a gradual structural transition from rhombohedral to orthorhombic. The average grain size was observed to decrease with increasing the concentration of La. The photocatalytic degradation of Rhodamine B (RhB) in the presence of the prepared nanoparticles was studied under visible light irradiation. The L0.06B0.94FO nanoparticles showed higher degradation efficiency compared to pure BiFeO3 (BFO) nanoparticles. Magnetic studies showed that La doping improved the magnetization of BFO due to the reduction in grain size and destruction of cycloid coupling of spins. Higher specific capacitance values were obtained for La doped BFO (LBFO) nanoparticles compared to BFO nanoparticles. A maximum specific capacitance of 219?F?g?1 was obtained at a current density of 1?A?g?1 for LBFO nanoparticles.  相似文献   
85.
A phytogenic feed additive (PFA) formulation was prepared with bioactive molecules—curcuminoids, gingerol, and carvacrol by encapsulating in nanofiber isolated from turmeric spent (turmeric nanofiber, TNF). This formulation was completely characterized by scanning electron microscope, ultra performance liquid chromatography, and gas chromatography and evaluated for its efficacy. PFA-encapsulated TNF (PFA@TNF) considerably increased mean body weight, decreased cholesterol level, mortality rate, and reduced Escherichia coli content of broilers than antibiotic growth promoter (AGP). The depth of crypts in the ileum of broilers was considerably reduced by the inclusion of PFA@TNF in diets compared with the AGP.  相似文献   
86.
Polycrystalline BiFeO3 (BFO) and Bi0.90Gd0.10Fe1?xZrxO3 (x = 0.0–0.10; BGFZx) ceramics were synthesized by solid‐state reaction method. Rietveld analysis of X‐ray diffraction patterns showed that BFO and BGFZx = 0.0 samples are stabilized in rhombohedral structure (space group R3c), whereas a small fraction of orthorhombic phase (space group Pn21a) is observed for BGFZx = 0.03–0.10 samples. Suppression and disappearance of some Raman modes indicated a structural phase transition with addition of Zr dopant at Fe site. Magnetic measurements exhibited weak ferromagnetic behavior of BGFZx samples with increasing Zr+4 concentrations. The insertion of Gd+3 ions at Bi+3 sites and nonmagnetic Zr+4 ions at Fe+3 sites in Fe–O–Fe network suppressed the spin cycloid structure of BFO which in turn enhanced the magnetization of these ceramics. Electron spin resonance spectra revealed the breaking of spin cycloid of BFO due to the development of free spins with addition of Zr+4 dopants at Fe sites. UV–Visible diffuse reflectance spectra showed one dd crystal field transition and two charge‐transfer (C–T) transitions along with a sharp absorption of light in visible region for all samples. Almost frequency‐independent dielectric constant and dielectric loss along with very low values of dielectric loss indicated greatly improved dielectric properties for BGFZx = 0.03–0.10 samples.  相似文献   
87.
To observe the effect of ENGAGE (a poly‐olefin elastomer) on compatibilization of industrially important incompatible blend, high‐density polyethylene (HDPE)/ethylene‐propylene diene elastomer (EPDM), 15 wt % ENGAGE is incorporated into the system and the latter is found satisfactorily efficient as compatibilizer for the above system. To improve some industrially pertinent properties another strategies are also followed in addition, incorporation of magnesium hydroxide [Mg(OH)2] and electron beam (EB) crosslinking into the system. The gel content was found to increase with radiation dose, EPDM content and Mg(OH)2 dispersion. ENGAGE interestingly increases the gel content that is, promotes crosslinking. It is unique that filler dispersion and crosslinked network formation maintain the compatibility of the ternary system, which is confirmed by X‐ray diffraction, differential scanning calorimetry, mechanical properties, and scanning electron microscope. The compatibilization, Mg(OH)2 dispersion, and EB crosslinking improve the mechanical, thermo mechanical, flame retardant properties, and phase morphology considerably. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44922.  相似文献   
88.
89.
A new bisphenol, 1,1-bis-[(4-hydroxyphenyl)-1-(4-phenylsulfonyl)phenyl)]ethane (DPSBP) was synthesized starting from diphenylsulfide and was characterized by spectroscopic methods. DPSBP was polycondensed with isophthalic acid chloride (IPC), terephthalic acid chloride (TPC) and a mixture of IPC and TPC (50:50 mol%) by phase-transfer catalysed interfacial polymerization method to obtain aromatic polyesters containing pendent 4-(phenylsulfonyl)phenyl groups. A series of copolyesters was also obtained by polycondensation of varying molar proportions of DPSBP and bisphenol-A (BPA) with TPC. (Co)polyesters exhibited inherent viscosities in the range 0.56–1.57 dLg?1 and number average molecular weights (Mn) were in the range 28,650–80,230 g/mol. Polyesters dissolved readily in common organic solvents such as dichloromethane, chloroform, tetrahydrofuran and aprotic polar solvents such as N-methylpyrrolidone, and N,N-dimethylacetamide. Tough, transparent and flexible films of polyesters could be cast from their chloroform solutions. X-Ray diffraction studies indicated amorphous nature of aromatic polyesters. Polyesters showed Tg values in the range 223–257 °C while T10 values were in the range of 469–484 °C indicating their excellent thermal stability.  相似文献   
90.
Energy demand, decreasing fossil fuel reserves, and health-related issues about pollutants have led researchers to search for renewable alternative fuels to either partially or fully replace fossil fuels. Among many alternative fuels, biodiesel became one of the most popular choices due to similar properties to that of conventional diesel. Biodiesel produces slightly lower brake thermal efficiency compared to that of conventional biodiesel, but has an advantage of reduced emissions of CO2, CO, HC, and smoke. However, biodiesel shows higher NOx emission which, when used in increased biodiesel market, may become a serious problem. Various strategies were attempted by different researcher to reduce NOx emissions. In this paper, various strategies, adapted for reducing NOx emissions of biodiesel fuel used in diesel engines for automobile applications, are reviewed and discussed. The strategies are grouped into three major groups, namely combustion treatments, exhaust after-treatments, and fuel treatments. Among various strategies discussed, fuel treatments, such as low temperature combustion, mixing fuel additives and reformulating fuel composition, reduce NOx emission without compromising other emission and performance characteristics and they seem to be promising for future biodiesel fuel.  相似文献   
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