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961.
Evaluation of pre-rigor injection of beef with proteases on cooked meat volatile profile after 1day and 21days post-mortem storage 总被引:2,自引:0,他引:2
This research was carried out to determine the effects of pre-rigor injection of beef semimembranosus muscle with nine proteases from plant and microbial sources, on the volatile profile of cooked beef after 1 day and 21 days post-mortem (PM) storage using Solid-phase microextraction gas chromatography mass spectrometry analysis. A total of 23 aldehydes, 5 ketones, 3 furans, 8 nitrogen and sulphur compounds, 4 alkanes, 7 alcohols and 6 terpenes were detected. Eleven volatile compounds characteristic of ginger flavour were detected in zingibain-treated meat. Benzaldehyde significantly increased (p<0.05) only in kiwifruit juice (KJ), fungal 31 protease and Asparagus protease (ASP) treated samples from 1day to 21days PM storage. A significant increase (p<0.05) in 3-methylbutanal was observed in KJ, bacterial and fungal protease treated samples at 21days PM storage. Treatments with bromelain, papain, ASP, actinidin, and KJ (except KJ 21days) proteases resulted in flavour profiles closer to that of the control beef sample. 相似文献
962.
Ali ME Hashim U Mustafa S Che Man YB Dhahi TS Kashif M Uddin MK Abd Hamid SB 《Meat science》2012,91(4):454-459
A test for assessing pork adulteration in meatballs, using TaqMan probe real-time polymerase chain reaction, was developed. The assay combined porcine-specific primers and TaqMan probe for the detection of a 109 bp fragment of porcine cytochrome b gene. Specificity test with 10 ng DNA of eleven different species yielded a threshold cycle (Ct) of 15.5 ± 0.20 for the pork and negative results for the others. Analysis of beef meatballs with spiked pork showed the assay can determine 100-0.01% contaminated pork with 102% PCR efficiency, high linear regression (r(2) = 0.994) and ≤ 6% relative errors. Residuals analysis revealed a high precision in all determinations. Random analysis of commercial meatballs from pork, beef, chicken, mutton and goat, yielded a Ct between 15.89 ± 0.16 and 16.37 ± 0.22 from pork meatballs and negative results from the others, showing the suitability of the assay to determine pork in commercial meatballs with a high accuracy and precision. 相似文献
963.
A weakly nonlinear analysis is carried out to derive the appropriate Korteweg–de Vries–Burgers-like equation for small, but finite amplitude, ion-acoustic waves in a dissipative plasma consisting of relativistic ions, Maxwell–Boltzmann distributed positrons and superthermal electrons. Our results show that in a such plasma, ion-acoustic shock waves, the spatial patterns of which are significantly modified by the relativistic and dissipative effects, may exist. Interestingly, we found that because of ion kinematic viscosity, an initial solitonic profile develops into a shock wave. This later evolves towards a monotonic profile (dissipation–dominant case) as the electrons deviate from their thermodynamic equilibrium. As the relativistic character of the plasma becomes important, the shock wave amplitude decreases. Our investigation may be taken as a prerequisite for the understanding of the shock-waves observed in the ionosphere and the auroral acceleration regions. We recall that when a high energy cosmic ray interacts with the earth’s atmosphere, it may produce an electron–positron pair with enormous velocities. The data obtained during the Alpha Magnetic Spectrometer (AMS) flight permitting to probe the radiation belts in the Earth’s innermost magnetosphere provided an evidence of the presence of positrons. 相似文献
964.
Hamid Mala Mohammad Dakhilalian Mohsen Shakiba 《International Journal of Communication Systems》2012,25(4):415-426
mCrypton is a 64‐bit lightweight block cipher designed for use in low‐cost and resource‐constrained applications such as RFID tags and sensors in wireless sensor networks. In this paper, we investigate the strength of this cipher against related‐key impossible differential cryptanalysis. First, we construct two 6‐round related‐key impossible differentials for mCrypton‐96 and mCrypton‐128. Then, using these distinguishers, we present 9‐round related‐key impossible differential attacks on these two versions. The attack on mCrypton‐96 requires 259.9 chosen plaintexts, and has a time complexity of about 274.9 encryptions. The data and time complexities for the attack on mCrypton‐128 are 259.7 chosen plaintexts and 266.7 encryptions, respectively. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
965.
Peyman Abdeshahian Najeeb Kaid Nasser Al-Shorgani Noura K.M. Salih Hafiza Shukor Abudukeremu Kadier Aidil Abdul Hamid Mohd Sahaid Kalil 《International Journal of Hydrogen Energy》2014
In view of increasing attempts for the production of renewable energy, the production of biohydrogen energy by a new mesophilic bacterium Clostridium sp. YM1 was performed for the first time in the dark fermentation. Experimental results showed that the fermentative hydrogen was successfully produced by Clostridium sp. YM1 with the highest cumulative hydrogen volume of 3821 ml/L with a hydrogen yield of 1.7 mol H2/mol glucose consumed. Similar results revealed that optimum incubation temperature and pH value of culture medium were 37 °C and 6.5, respectively. The study of hydrogen production from glucose and xylose revealed that this strain was able to generate higher hydrogen from glucose compared to that from xylose. The profile of volatile fatty acids produced showed that hydrogen generation by Clostridium sp. YM1 was butyrate-type fermentation. Moreover, the findings of this study indicated that an increase in head space of fermentation culture positively enhanced hydrogen production. 相似文献
966.
Abdolrasoul Rangrazi Hamid Niazmand Hamid Momahedi Heravi 《Korean Journal of Chemical Engineering》2013,30(8):1588-1593
The effects of nitrogen and argon dilution on NO X emission of turbulent propane-air non-premixed flame in a furnace are experimentally investigated. Dilution is an effective process in reducing NO X emission, since diluents cause an increase in the mass flow of the fuel, and consequently the temperature in the combustion chamber and NO X emission decreases. We measured NO X emission and temperature for a wide range of dilution and equivalence ratios. The results show that nitrogen dilution is more effective than argon dilution in reducing NO X emission. In addition, both dilutions caused the yellow color of the non-premixed flame to turn blue, which indicates more complete combustion and better mixing of fuel and oxidant. 相似文献
967.
Hossein Eisazadeh Hamid Reza Khorshidi 《Polymer-Plastics Technology and Engineering》2013,52(15):1591-1596
Nanocomposite of polyaniline containing Fe3O4 and Fe2O3 was synthesized by a chemical method using hydroxypropylcellulose as a steric stabilizer. The characteristics of product such as, morphology, conductivity, and particle size were studied. The results indicate that, these properties were dependent on the surfactant, amount and type of metallic oxide. When the concentration of Fe2O3 and Fe3O4 increased from 1 to 5 g/L, in PAn/Fe2O3 and PAn/Fe3O4 composites the conductivity decreased from 1.2 × 10?6 to 1.1 × 10?8 and 2.8 × 10?6 to 1.1 × 10?8S/cm, respectively, while the particle size of nanocomposite increased from 96 to 110, and 97 to 115 nm, respectively. 相似文献
968.
Saffron is the most expensive spice and Iran is the largest producer of this crop in the world. Saffron quality is profoundly affected by the drying method. Recent research has shown that hybrid photovoltaic–thermal solar power systems are more efficient in comparison with individual photovoltaic and thermal systems. In addition, heat pump dryers are highly energy efficient. Furthermore, they are suitable for heat-sensitive crops such as saffron. Therefore, in the present study, the performance of a hybrid photovoltaic–thermal solar dryer equipped with a heat pump system was considered for saffron drying, in order to obtain a high-quality product and reduce fossil fuel consumption. The effect of air mass flow rate at three levels (0.008, 0.012, and 0.016 kg/s), drying air temperature at three levels (40, 50, and 60°C), and two different dryer modes (with and without the heat pump unit) on the operating parameters of the dryer was investigated. The results of the investigation showed that total drying time and energy consumption decreased as air flow rate and drying air temperature increased. Applying a heat pump with the dryer led to a reduction in the drying time and energy consumption and an increase in electrical efficiency of the solar collector. The average total energy consumption was reduced by 33% when the dryer was equipped with a heat pump. Maximum values for electrical and thermal efficiency of the solar collector were found to be 10.8 and 28%, respectively. A maximum dryer efficiency of 72% and maximum specific moisture extraction rate (SMER) of 1.16 were obtained at an air flow rate of 0.016 kg/s and air temperature of 60°C when using the heat pump. 相似文献
969.
Md. Mamun-Or-Rashid Muhammad Mahbub Alam Md. Abdul Hamid Choong Seon Hong 《Wireless Networks》2010,16(3):713-729
Fair scheduling is an ideal candidate for fair bandwidth sharing and thereby achieving fairness among the contending flows
in a network. It is particularly challenging for ad hoc networks due to infrastructure free operation and location dependent
contentions. As there is no entity to serve coordination among nodes, we need a mechanism to overcome inherent unreliability
of the network to provide reduced collision and thereby higher throughput and adequate fair allocation of the shared medium
among different contending flows. This paper proposes a flow rank based probabilistic fair scheduling technique. The main
focus is to reduce the collision probability among the contending flows while maintaining the prioritized medium access for
those flows, which ensures a weighted medium access control mechanism based on probabilistic round robin scheduling. Each
flow maintains a flow-table upon which the rank is calculated and backoff value is assigned according to the rank of the flow, i.e., lower backoff interval
to lower ranked flow. However, flow-table instability due to joining of a new flow, partially backlogged flow, hidden terminal and partially overlapped region exhibits
a challenging problem that needs to be mitigated for our mechanism to work properly. We take appropriate measures to make
the flow-table stabilized under such scenarios. Results show that our mechanism achieves better throughput and fairness compared to IEEE
802.11 MAC and existing ones. 相似文献
970.