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41.
This paper presents the current situation and projected planning of the electricity generation sector for Iskandar Malaysia by implementing a model to optimise the cost, utilise the usage of available renewable energy sources, and achieve carbon dioxide reduction targets. This Mixed Integer Linear Programming model was developed with the main objective of minimising the total cost of electricity generation, taking into consideration energy demand, reserve margin, electricity generation, peak and base generation, resource availability, and CO2 emission. Data for the year 2013 were forecasted until 2025 to illustrate the analysis for this study, and are represented via four scenarios. This optimal model is capable of balancing types of fuel and switching coal plants to natural gas power plants. It also enhances the use of renewable energy (RE) to meet CO2 emission targets. The model is further integrated with several other considerations related to energy systems, such as suitability of power plants as peak or base plants, RE resource availability, intermittency of solar power, losses during transmission, fuel selection for biomass, decision to retrofit existing coal power plant to NG power plant, and construction lead time of power plants. The results for this study determined that the optimal scenario is Scenario 3 (CS3). This research proves that Iskandar Malaysia can reduce CO2 emission by 2025 via utilisation of RE. This model is generic and can be applied to any case study, which would be useful for assisting government policy-making.  相似文献   
42.
ABSTRACT

Magnesium layered hydroxide (MLH) intercalated with anionic 3-(4-methoxyphenyl)propionic acid (MPP) was synthesised by a direct reaction method using magnesium oxide and MPP as precursors. A further coating of chitosan was applied on the external surface of MLH–MPP nanocomposite to form a new material, named MLH–MPP/chitosan nanocomposite. The XRD pattern showed an intense and sharp peak at basal spacing 18.9 Å, proving that MPP anions were successfully intercalated into the interlayer gallery of MLH in a monolayer arrangement. The XRD pattern of the MLH–MPP/chitosan nanocomposite shows similar peaks with the MLH–MPP nanocomposite. The result was also supported by FTIR spectra and elemental analysis. TGA/DTG spectra showed that the thermal stabilities of the guest anion in the both nanocomposites were markedly enhanced. A controlled-release study of the MPP ion from the MLH–MPP/chitosan nanocomposite showed a slower release compared to MLH–MPP nanocomposite with an initial rapid release and slow release thereafter. Meanwhile, the release behaviours of MPP ions from both nanocomposites were governed by pseudo-second order kinetics. This result highlights the potential of the nanocomposite as an encapsulated material for the controlled-release formulation of MPP anions.  相似文献   
43.
In this study, nanocrystalline magnesium zinc ferrite nanoparticles were successfully prepared by a simple sol–gel method using copper nitrate and ferric nitrate as raw materials. The calcined samples were characterised by differential thermal analysis/thermogravimetric analysis, Fourier transform infrared spectroscopy and X‐ray diffraction. Transmission electron microscopy revealed that the average particle size of the calcined sample was in a range of 17–41 nm with an average of 29 nm and has spherical size. A cytotoxicity test was performed on human breast cancer cells (MDA MB‐231) and (MCF‐7) at various concentrations starting from (0 µg/ml) to (800 µg/ml). The sample possessed a mild toxic effect toward MDA MB‐231 and MCF‐7 after being examined with MTT (3‐[4, 5‐dimethylthiazol‐2‐yl]‐2, 5 diphenyltetrazolium bromide) assay for up to 72 h of incubation. Higher reduction of cells viability was observed as the concentration of sample was increased in MDA MB‐231 cell line than in MCF‐7. Therefore, further cytotoxicity tests were performed on MDA MB‐231 cell line.Inspec keywords: sol‐gel processing, nanoparticles, nanofabrication, magnesium compounds, zinc compounds, toxicology, biological organs, cancer, cellular biophysics, nanomedicine, calcination, differential thermal analysis, Fourier transform infrared spectra, X‐ray diffraction, transmission electron microscopy, particle size, organic compoundsOther keywords: sol‐gel method, cytotoxic effects, breast cancer cell line, MDA MB‐231 in vitro, nanocrystalline magnesium zinc ferrite nanoparticles, copper nitrate, ferric nitrate, raw materials, calcined samples, differential thermal analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, average particle size, cytotoxicity testing, human breast cancer cells, mild toxic effect, 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5 diphenyltetrazolium bromide) assay, cell viability, MCF‐7, MDA MB‐231 cell line, size 17 nm to 41 nm  相似文献   
44.
An investigation is reported of the 75 at% nickel section of the Ni-Cr-Al-Ru system at 1523 and 1273 K. Constitutional data obtained by electron probe microanalysis, X-ray diffraction and microscopical examination are presented as partial isothermal sections. At 1523 K, the major part of the section consists of phase, while the aluminium-rich region contains a and+ region; the extent of the solid solution of chromium and ruthenium in totals ~ 4 at%. The ruthenium-rich corner of the section shows a two-phase region consisting of + ruthenium-rich solid solution. At 1273 K the,+ and + ruthenium regions increase in extent. The/ mismatch values in the equilibrated alloys studied lie in the range ~ –0.08 to –0.39%. Constitutional features of as-cast alloys are also reported.  相似文献   
45.
The mutual separation of a mixture of cetyltrimethyl ammonium chloride (CTAC), methyl trioctyl ammonium bromide (MTOB), dodecyltrimethyl ammonium chloride (DTAC), benzyltrimethyl ammonium chloride (BTAC) and tetrabutyl ammonium bromide (TBAB), was achieved on silica high performance thin layer chromatographic plates using dimethyl sulfoxide with aqueous sodium-l-tartrate dibasic dihydrate as the solvent system. The effect of concentration of sodium-l-tartrate dibasic dihydrate on the mobility of all the five quaternaries was examined. The limit of detection of CTAC, MTOB, DTAC, BTAC and TBAB was estimated as 0.6, 0.6, 0.3, 0.6 and 0.3 μg/zone, respectively. The method developed was utilized to identify these surfactants in different spiked water samples after their preliminary separation.  相似文献   
46.
Carboxymethyl sago pulp (CMSP)/pectin hydrogel beads were synthesized by calcium crosslinking and further crosslinked by electron beam irradiation to form drug carrier for colon‐targeted drug. Sphere‐shaped CMSP/pectin 15%/5% hydrogel beads is able to stay intact for 24 h in swelling medium at pH 7.4. It shows pH‐sensitive behavior as the swelling degree increases as pH increases. Fourier transform infrared spectroscopy analysis confirmed the absence of chemical interaction between hydrogel beads and diclofenac sodium. Differential scanning calorimetric and X‐ray diffraction studies indicate the amorphous nature of entrapped diclofenac sodium. The drug encapsulation efficiency is up to about 50%. Less than 9% of drug has been released at pH 1.2 and the hydrogel beads sustain the drug release at pH 7.4 over 30 h. This shows the potential of CMSP/pectin hydrogel beads as carrier for colon‐targeted drug. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43416.  相似文献   
47.
Medium density fiberboard (MDF) is one of the widely used wood-based panels to manufacture building components such as furniture units for interior applications. Although MDF is an excellent product it is prone to fire hazard which should be enhanced using flame retardants during its manufacture. Properties of the flame retardant urea formaldehyde (UF) MDF made using a dry process from rubberwood fibers were investigated. Flame retardant chemicals that were evaluated include sodium aluminate, zinc borate and aluminum trihydrate, which were incorporated with rubberwood fibers to manufacture experimental MDF. Four concentration levels, 10%, 15%, 20% and 30% of fire retardants and 15% urea formaldehyde resin based on oven dry fiber weight were used to manufacture experimental panels. Physical and mechanical properties including thickness swelling, water absorption, bending characteristics, and internal bond strength of the samples were determined. Flame retardant properties of the panels were also investigated using a Cabinet Method along with char index, weight loss and size of ellipse area. Finally, thermogravimetry method was employed to analyze thermal properties of the MDF panels. The results showed that thickness swell and water absorption decreased as the flame retardant increased. The MOR was not affected by the flame retardant treatment for boards bonded with urea formaldehyde resin. The internal bond strength showed a small reduction compared with the controls as the flame retardant chemicals increased but not for boards treated with 5% aluminum trihydrate. When the concentration of flame retardant chemicals increased to 30%, the internal bond generally decreased. Char index, area of ellipse and weight loss reduced as the percentage of flame retardant increased. Sodium aluminate showed the best performance in reducing thermal degradation followed by aluminum trihydrate and zinc borate. Aluminum trihydrate cured closely resemble that of the control during the gelation test.  相似文献   
48.
Colloidal gas aphrons (CGAs), generated from dilute solutions of four surfactants, were used to clarify palm oil mill effluent (POME), suspensions of microalgae and suspensions of three inorganic minerals. In POME and the algal suspensions, each CGA was most effective at a pH value close to the pK value of the surfactant concerned. This effect was not tested in the inorganic suspensions. The efficiency of air utilization was directly related to the concentration of solids in the suspensions, the size, density and nature of the solids having secondary effects. Comparison with data in the literature led to a general correlation embracing a variety of suspensions and flotation systems. Shedding of collected material from the foam layer was also a direct function of solids concentration. CGAs offer advantages over other systems of air-assisted flotation in relation to the requirements for equipment and to the management of process operations.  相似文献   
49.
Multimedia Tools and Applications - Analysis of facial images decoding familial features has been attracting the attention of researchers to develop a computerized system interested in determining...  相似文献   
50.
Soy protein is known for its eco-friendly, sustainable, and biodegradable qualities that are likely used as raw material in producing bioadhesive. However, soy protein-based adhesive are lacking in terms of adhesive strength and water-resistance compared to commercial formaldehyde-based adhesives such as phenol and urea-formaldehyde resin. Therefore, continuous research has been done to improve adhesive performance. This can be done via physical or modification methods, including the usage of cross-linking agents, structural modification, enzymatic modification, and the addition of additives. This review will cover these modification methods that give significant enhancement to the water-resistance and adhesive strength of soy protein-based adhesives.  相似文献   
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