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71.
The effects of physical refining on the formation of 3-monochloropropane-1,2-diol esters in relation to palm oil minor components 总被引:2,自引:0,他引:2
The formation of 3-monochloropropane-1,2-diol (3-MCPD) esters in refined palm oil during deodorisation is attributed to the intrinsic composition of crude palm oil. Utilising D-optimal design, the effects of the degumming and bleaching processes on the reduction in 3-MCPD ester formation in refined palm oil from poor-quality crude palm oil were studied relative to the palm oil minor components that are likely to be their precursors. Water degumming remarkably reduced 3-MCPD ester formation by up to 84%, from 9.79 mg/kg to 1.55 mg/kg. Bleaching with synthetic magnesium silicate caused a further 10% reduction, to 0.487 mg/kg. The reduction in 3-MCPD ester formation could be due to the removal of related precursors prior to the deodorisation step. The phosphorus content of bleached palm oil showed a significant correlation with 3-MCPD ester formation. 相似文献
72.
73.
Hani Hafeeza Halim Elfy Williams Dee Mohd Sabri Pak Dek Azizah Abdul Hamid Ahmad Ngalim Nazamid Saari 《International Journal of Food Properties》2018,21(1):2378-2389
The present work aimed to compare the main ergogenic attributes of two commercialized stages (young and mature) of coconut water (CW) obtained from four coconut varieties. The changes of electrolytes and sugars in CW upon maturation were quantified by inductively coupled plasma mass spectrophotometer and high-performance liquid chromatography, respectively. Based on the electrolyte profiling, potassium yielded the highest amount (ranging from 237.41 to 361.20 mg/100 mL) followed by sodium, magnesium, calcium, iron, manganese, copper, selenium, and zinc across all the maturity stages tested. For sugars, there were lower amounts of fructose and glucose, but a higher amount of sucrose with the maturation of the fruits. In conclusion, the amount of beneficial nutrients in the form of sugars and minerals was higher than that of young CW, and the ergogenic attributes of mature CW especially from MATAG variety (M-MATAG) were the best to be exploited further in the development of natural energy drinks. 相似文献
74.
Potential Use of FTIR-ATR Spectroscopic Method for Determination of Virgin Coconut Oil and Extra Virgin Olive Oil in Ternary Mixture Systems 总被引:1,自引:0,他引:1
The aim of this study was to investigate the feasibility of Fourier-transform infrared (FTIR) spectroscopy combined with multivariate
calibrations of partial least square (PLS) and principle component regression (PCR) for analysis of virgin coconut oil (VCO)
in the ternary mixture with palm oil (PO) and olive oil, and for analysis of extra virgin olive oil (EVOO) mixed with soybean
oil (SO) and corn oil (CO). The spectra of individual oils and their blends with certain concentrations were scanned using
horizontal attenuated total reflectance accessory at mid-infrared region of 4,000–650 cm−1. The optimal frequency regions selected for calibration models were based on its ability to give the highest values of coefficient
of determination (R
2) and the lowest values of root mean standard error of calibration (RMSEC). PLS was slightly better for quantitative analysis
of VCO and EVOO compared with PCR. VCO in ternary mixtures is successfully determined at frequency region of 1,200–1,000 using
second derivative FTIR spectra with R
2 and RMSEC values of 0.999 and 0.200, respectively. Meanwhile, EVOO is best determined at 1,200–1,000 using first derivative
FTIR spectra with R
2 and RMSEC values of 0.999 and 0.975, respectively. The results showed that FTIR spectroscopy offers accurate and reliable
technique for quantitative analysis of VCO and EVOO in ternary systems. In addition, the developed method can be used for
the monitoring of VCO and EVOO adulteration with cheaper oils like PO in VCO as well as SO and CO in EVOO. 相似文献
75.
Thirty randomly selected Aeromonas isolates from food and the environment in Abu Dhabi, United Arab Emirates, were characterized for putative virulence determinants, such as production of cytotoxin, cytotonic toxin, and hemolysin and their capacity to adhere to and invade Henle 407 cells in vitro. Seventy percent of the tested isolates were cytotoxin producers, and 80% were hemolytic. Cytotoxin was produced by 6 of 7 A. hydrophila strains, 6 of 13 A. caviae strains, and 6 of 7 A. veronii bv. sobria strains, mostly from food sources. A. schubertii, A. jandaei, and A. trota also produced both cytotoxin and hemolysin. All of the 30 isolates tested adhered to Henle 407 cells, but none were able to invade the cells, as determined with the in vitro assay. However, no significant correlation of the presence of these putative virulence factors was found among these aeromonad food isolates. 相似文献
76.
Michael H. Gordon Ibrahim Abdul Rahman 《Journal of the American Oil Chemists' Society》1991,68(8):574-576
The effect of various processing procedures on the composition and oxidative stability of coconut oil has been studied. The
crude oil is relatively stable but major reductions in oxidative stability occur during the bleaching of oil degummed with
phosphoric acid; during alkali refining; during the deodorization of oil degummed with citric acid and bleached; and during
the deodorization of oil processed with a combined phosphoric acid degumming and bleaching operation. The reasons for the
loss of oxidative stability during processing are discussed with reference to changes in the composition of the oil. Residual
traces of citric acid or phosphoric acid play an important role in stabilizing processed oils. The tocopherol content is also
important, although no additional stabilization of the oil occurs on adding levels of tocopherol above those present naturally
in the crude oil. A combined phosphoric acid degumming and bleaching process leads to smaller losses of tocopherols than sequential
treatments. 相似文献
77.
Yew Joon Tam Morvarid Akhavan Rezaei Mohd Lila Mohd Azmi Abdul Rani Bahaman Sewn Cen Lo 《分离科学与技术》2016,51(5):816-829
Univariate screening on factors affecting the purification performance of recombinant hepatitis B surface antigen (HBsAg) on ion exchange chromatography (IEC) and size exclusion chromatography (SEC) and the establishment of a two-step purification strategy were performed. Amongst four IEC adsorbents examined, the use of Q Sepharose XL IEC adsorbent under optimized conditions together with optimized SEC purification was able to efficiently purify HBsAg. An established purification strategy comprising the two techniques further demonstrated adaptability for scale-up operations with a final total purification factor (PF) of 94.82 ± 16.20, HBsAg purity of 95.48% and recovery yield of 78.07%. 相似文献
78.
Abdul Latif Ahmad Choe Peng Leo Syamsul Rizal Abd. Shukor 《Journal of Porous Materials》2009,16(1):33-40
Porous γ-alumina with well arranged secondary mesopores has been contrived using nanosized templating units. The pore size
of templated mesopores is precisely controlled as the pore shrinkage is insignificant. The primary pore diameter is ca. 4 nm
and the secondary pore diameter is ca. 50 nm. The porous material was characterized using N2 adsorption/desorption, TEM, XRD and FT-IR. γ-alumina with bimodal pore size distribution shows improved intra-particle diffusion
compared to γ-alumina with unimodal pore size distribution in a simple dye adsorption test. γ-alumina with different porous
structures were then impregnated with vanadium oxide for catalytic effect comparison. It was perceived that secondary pores
improve the styrene oxidation rate after the conversion of styrene reaches 30%. 相似文献
79.
Synthesis and characterization of (poly (N-vinyl formamide)—pregelled starch—graft copolymer 总被引:1,自引:0,他引:1
Khaled M. Mostafa Abdul Rahim Samarkandy Azza A. El-Sanabary 《Journal of Polymer Research》2010,17(6):789-800
Bromate / cyclohexanone redox system was investigated as a novel initiator for graft copolymerization of N-vinyl formamide
onto pregelled starch. A number of variables in the grafting reaction were investigated including N-vinyl formamide, cyclohexanone,
bromate ion, sulphuric acid and pregelled starch concentrations, material to liquor ratio along with polymerization time and
temperature. The graft copolymers were evaluated in terms of graft yield, graft reaction efficiency and homopolymer formation
(%). The optimum conditions for grafting of N-vinyl formamide onto pregelled starch are: N-vinyl formamide 50% based on weight
of substrate, cyclohexanone 15 mmol / l, bromate ion, 30 mmol / l, liquor ratio 10, pH 6, time 120 min., and temperature 40°C.
On the other hand, characterizations of the resultant copolymers with respect to swelling capacity, solubility %, metal ion
up-take and suitability as a sizing agent for cotton textiles were investigated. The results obtained reflect that, the resultant
copolymer shows better results for the aforementioned properties in comparison with that obtained from native pregelled starch
as a starting substrate. 相似文献
80.
Weldalite 050, a high-strength Al-Mg-Li alloy, was evaluated for its corrosion resistance in deaerated and air saturated Arabian
Gulf water to determine its suitability for marine applications. Weight loss and electrochemical studies showed that the alloy
had minimum corrosion rates of 1.82 and 4.82 mpy (mils per year), respectively, in deaerated and air saturated Arabian Gulf
water with very high total dissolved solids (TDS) content. Weldalite 050 exhibited good resistance to corrosion at velocities
up to 3.9 m/s. The formation of Al2MgLi, Al-Li, Al12Mg17, and Al-Li precipitates has a pronounced effect on its corrosion resistance. The corrosion resistance of Weldalite 050 compares
favorably with that of alloys 5052 and 5054, wrought alloys 6061 and 6013, and silicon carbide (SiC) reinforced alloys 6061
and 6013. 相似文献