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101.
Evaluation of papaya seeds as a novel non-conventional low-cost adsorbent for removal of methylene blue 总被引:1,自引:0,他引:1
Hameed BH 《Journal of hazardous materials》2009,162(2-3):939-944
The feasibility of using papaya seeds (PS), abundantly available waste in Malaysia, for the cationic dye (methylene blue) adsorption has been investigated. Batch adsorption studies were conducted to study the effects of contact time, initial concentration (50-360 mg/L), pH (3-10) and adsorbent dose (0.05-1.00 g) on the removal of methylene blue (MB) at temperature of 30 degrees C. The equilibrium data were analyzed by the Langmuir, the Freundlich and the Temkin isotherms. The data fitted well with the Langmuir model with a maximum adsorption capacity of 555.557 mg/g. The pseudo-second-order kinetics was the best for the adsorption of MB by PS with good correlation. The results demonstrated that the PS is very effective to remove methylene blue from aqueous solutions. 相似文献
102.
Physicochemical and bacteriological status of a local textile mill effluent showed considerably high values of temperature (40 degrees C), pH (9.50), EC (3.57mus/m), BOD (548mgl(-1)), COD (1632mgl(-1)), TSS (5496mgl(-1)), TDS (2512mgl(-1)), heavy metals ions (0.28-6.36mgl(-1)) and color above the prescribed fresh water limits. However, a considerable decline in almost all pollution indicators from source to sink indicated signs of natural remediation. Ten bacteria strains isolated from effluent showed comparatively higher resistance (MRL) (mgl(-1)) (average) for 10 heavy metals than against four structurally different dyes tested on solid media of mineral salt. Overall bacterial resistance was quite high against Fe(3+) (2820), Cr(3+) (1203), Zn(2+) (1122), Mn(2+) (804) and Pb(2+) (435), whereas, it varied amid 300-500 in four dyes. Bacterial decolorization/degradation of dyes indicated on solid media was confirmed through experiments carried out in liquid broth. 相似文献
103.
M. Abbas Ali Ayesha Nargis Noor Hidayu Othman Ahmadil Fitri Noor Golam Sadik Jewel Hossen 《International Journal of Food Properties》2017,20(11):2569-2580
The oxidative stability and compositional characteristics of the pumpkin seed oil (PSO) exposed to microwaves were studied during heating at 170°C. The oxidative indices such as free fatty acid (FFA), peroxide value (PV), p-anisidine value (p-AV), TOTOX, specific extinctions and thiobarbituric acid (TBA) value of oils were significantly increased, and the increments were found to be significantly higher (P < 0.05) in unroasted seed oil as compared to roasted seed oil. The relative contents of polyunsaturated fatty acids (PUFAs) were decreased to 84.7%, and saturated fatty acids (SFAs) were increased to 119.5% in unroasted sample, after 9 h of heating. On the other hand, in 12 min roasted samples, the relative contents of PUFAs were decreased to 97.0%, and SFAs were increased to 102.6% after 9 h of heating. The triacylglycerol species LLL and OLL levels were decreased as a consequence of increased heating time, and the reduction tended to be significantly higher in unroasted samples as compared to roasted ones. The oxidation products formed were also investigated by FTIR. The present results indicated that microwave roasting of pumpkin seeds markedly enhanced the oxidative stability of the oils during heating. 相似文献
104.
Ayesha Kausar 《Fullerenes, Nanotubes and Carbon Nanostructures》2017,25(2):109-123
This review focuses on an inimitable multilayer fullerene material commonly referred as carbon nano onion (CNO). Among carbon nanomaterials, CNO is the least studied form. CNO has unique 0-D structure, small diameter of <10 nm, high electrical conductivity, fine dispersibility, and other superior structural and physical features. Different preparation and functionalization routes have been used for this unique nanocarbon structure. The article summarizes essential available categories of polymer/CNO composite such as polyaniline/CNO, polypyrrole/CNO, polythiophene/CNO, poly(?-caprolactone)/CNO, polystyrene/CNO, poly(diallyldimethyl-ammonium chloride)/CNO, and polyenediyne/CNO. Moreover, significant technical application of CNO-based materials has been discussed in supercapacitor, solar cell, Li-ion battery, dielectric, and biomedical materials. 相似文献
105.
Alfakeer M. Abdallah M. Abdel Hameed R. S. 《Protection of Metals and Physical Chemistry of Surfaces》2020,56(1):225-232
Protection of Metals and Physical Chemistry of Surfaces - The inhibiting action of nonionic surfactants, namely, propoxylated fatty esters (PFE) with different number of propylene oxide toward the... 相似文献
106.
Shivani Chaturvedi Ayesha Sadaf Amrik Bhattacharya Prasant Kumar Rout Lata Nain Sunil Kumar Khare 《European Journal of Lipid Science and Technology》2021,123(11):2000376
The microbial lipids isolated from oleaginous yeasts are a potential alternative to tree borne oils. There is a need to optimize and enhance the production of lipid by various stress approaches. In the present study, yeasts are subjected to physico-chemical stresses, and growth, as well as lipid concentration at different time intervals are monitored. It is found that the nanoparticles (NP) such as Ag-NP and Zn-NP have an inhibitory effect on yeast growth. Most yeast strains show an increase in growth and lipid accumulation when ionic liquid (1-ethyl-3-methylimidazolium acetate) ([EMIM][OAc]) and table salt (NaCl) stress are applied. Lipid is chemically characterized using gas chromatography furnished with flame ionization detector (GC-FID), GC/MS, and NMR techniques. It contains a higher percentage of saturated fatty acids (SFA: 74.3%), monounsaturated fatty acids (19.1%) with low amounts of polyunsaturated fatty acids (1.9%). The thermo-stability study reveals that the lipid have higher volatility (380–410 °C) as closely compared with coconut oil, and much lower with respect to the winged bean oil (430–470 °C). The melting point of the lipids (37 °C) is determined through differential scanning calorimetry (DSC). The DSC and physico-chemical properties are supported that the yeast lipids may use as a cocoa-butter substitute. Production of lipid under NaCl stress (200 × 10−3 m ) is more than 60.4% higher as compared to the control. However, the combined stress effect of NaCl (200 × 10−3 m ) and 15 × 10−3 m of [EMIM][OAc] results in more than 96.4% yield of lipid. The exchange of inorganic and organic ions in combined treatment forces the microbial cells to accumulate more amounts of lipid, which may form a lipid-emulsion layer to protect the cell from osmosis. It is interestingly observed that the stress cells shift the flux to accumulate a significantly improved percentage of SFA, which could be provided better protection cover due to its expanded structure, less reactive characteristics, and completely insoluble nature in ionic-aqueous solvent. Practical applications: Oleaginous yeast is multiplied in a very limited space, and easily scalable for sustainable production of lipid to meet its commercial demand. This novel approach for enhancing the yield of lipid with the application of synergistic stress in between NaCl and the green solvent (ionic liquid) is being reported for the first time. This lipid has potential alternative applications as cocoa-butter. 相似文献
107.
A novel multistage solar desalination system with a photovoltaic heater was manufactured. The base of the down basin of the solar still had a layer of paraffin wax with a mass of 13 kg as a phase change material. The system has been studied to evaluate the enhancement of freshwater. Saltwater was heated by solar radiation and by a direct current water heater. The surfaces of condensation vapor, such as the pyramid glass cover and lower surface of two stacked trays, were designed. This is to improve the productivity of freshwater by decreasing the resistance of condensation. The high temperature of the glass cover is modified by using a cooling water shower, especially at the highest intensity. The study includes parameters, such as cooling water shower flow rate, down basin water level, and the effect of the heater. It is observed that the novel solar desalination is proportional to solar radiation, paraffin wax, the heat input from a heater, cooling water shower flow rate, and down basin water level. The Multiple Stage Effect Photovoltaic Heater (MSEPVH) can produce 15 L/day of distilled water. The excellent flow rate of cooling water, the total freshwater, and the efficiency of MSEPVH for the optimal day were mathematically and experimentally determined. 相似文献
108.
Khadom Anees A. Abod Baker M. Mahood Hameed B. Kadhum Abdul Amir H. 《Journal of Failure Analysis and Prevention》2018,18(5):1300-1310
Journal of Failure Analysis and Prevention - Control of galvanic corrosion of steel–brass couples in petroleum waste water solution by Curcuma longa was studied at different temperatures,... 相似文献
109.
Hameed Khalid W. Eya Nnabuike Noras James M. Abd-Alhameed Raed A. 《Telecommunication Systems》2020,73(1):105-112
Telecommunication Systems - Multi-user transmission, whereby users share time and frequency resources has been an active research area in the past decade in which the uniform linear array (ULA) was... 相似文献
110.
Salman Ayesha Qureshi Ijaz Mansoor Saleem Shahryar Saeed Sarah Alyaei Bahman R. 《Wireless Networks》2018,24(6):2205-2219
Wireless Networks - Cognitive radios and femtocell networks are gaining much popularity due to the formers ability to carry out unlicensed transmission in licensed bands and the latter’s... 相似文献