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排序方式: 共有1042条查询结果,搜索用时 15 毫秒
41.
Aminu Umar Kura Nooraini Mohd Ain Mohd Zobir Hussein Sharida Fakurazi Samer Hasan Hussein-Al-Ali 《International journal of molecular sciences》2014,15(4):5916-5927
Layered hydroxide nanoparticles are generally biocompatible, and less toxic than most inorganic nanoparticles, making them an acceptable alternative drug delivery system. Due to growing concern over animal welfare and the expense of in vivo experiments both the public and the government are interested to find alternatives to animal testing. The toxicity potential of zinc aluminum layered hydroxide (ZAL) nanocomposite containing anti-Parkinsonian agent may be determined using a PC 12 cell model. ZAL nanocomposite demonstrated a decreased cytotoxic effect when compared to levodopa on PC12 cells with more than 80% cell viability at 100 μg/mL compared to less than 20% cell viability in a direct levodopa exposure. Neither levodopa-loaded nanocomposite nor the un-intercalated nanocomposite disturbed the cytoskeletal structure of the neurogenic cells at their IC50 concentration. Levodopa metabolite (HVA) released from the nanocomposite demonstrated the slow sustained and controlled release character of layered hydroxide nanoparticles unlike the burst uptake and release system shown with pure levodopa treatment. 相似文献
42.
Metallurgical and Materials Transactions A - The increase in use of dual-phase (DP) steel grades by vehicle manufacturers to enhance crash resistance and reduce body car weight requires the... 相似文献
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The effect of addition of essential oils of marjoram (Origanum marjorana L.) and rosemary (Rosmarinus officinalis L.) at concentration of 200 mg/kg to beef patties formulated with 200 g/kg mechanically deboned poultry meat (MDPM) was studied. The proximate composition, lipid oxidation, sensory characteristics and microbial counts of beef patties manufactured with 200 g/kg MDPM (percentage of lean portion) were assessed during frozen storage at ?18 °C. Beef patties formulated with MDPM (200 g/kg) showed significant (P < 0.05) reduction in protein content and significant (P < 0.05) increase in fat content. Incorporating MDPM in beef patties formulation significantly (P < 0.05) increased the TBARS (Thiobarbituric acid reactive substance) values and significantly (P < 0.05) reduced the flavor and overall acceptability scores. Addition of essential oils of marjoram and rosemary at level of 200 mg/kg significantly (P < 0.05) reduced the TBARS and significantly (P < 0.05) increased the sensory scores of beef patties during frozen storage period. Overall, the study indicated the potential use of natural herbal essential oils to protect against lipid oxidation and improve the sensory attributes of beef patties formulated with MDPM. 相似文献
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Ultrasound‐based,in‐line monitoring of anaerobe yeast fermentation: model,sensor design and process application
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Sven Hoche Daniel Krause Mohamed A. Hussein Thomas Becker 《International Journal of Food Science & Technology》2016,51(3):710-719
In order to implement process analytical technology in beer manufacturing, an ultrasound‐based in‐line sensor was developed which is capable to determine sound velocity and density via the multiple reflection method. Based on a systematic study of the ternary system water–maltose–ethanol, two models were established to estimate the critical process parameters: sugar and ethanol mass fraction. The sound velocity‐based model showed unreasonable high errors although temperature variations and deviations due to dissolved CO2 were corrected. In contrast, the sound velocity–density–temperature model provided an average root mean square error of 0.53%g/g sugar and 0.26%g/g ethanol content for the main fermentation. Method, sensor and model showed the capability to capture the process signature which may be related to product and process quality. 相似文献
47.
Performance of PAM/PEI gel system for water shut‐off in high temperature reservoirs: Laboratory study
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Khalid S. M. ElKarsani Ghaithan A. Al‐Muntasheri Abdulla S. Sultan Ibnelwaleed A. Hussein 《应用聚合物科学杂志》2015,132(17)
A polymer gel is one of the common remediate methods to either reduce or totally block excessive water production in oilfields. Some systems demonstrated an excellent performance in treating the problem like polyacrylamide tert‐butyl acrylate (PAtBA)/polyethylenimine (PEI). In this study, polyacrylamide (PAM) was introduced as a cheap alternative to PAtBA that can tolerate high salinity reservoirs. The thermal stability of the PAM/PEI polymeric gel in saline water was examined at 150°C (302F). Samples prepared in sea water showed better stability compared with distilled and field water. Dynamic rheology and core‐flooding experiments were used to evaluate the PAM / PEI gel system at high temperatures. NaCl and NH4Cl were evaluated as a possible retarders for delaying the gelation time in order to achieve a successful placement. NH4Cl was found to be more effective retarder. Core‐flooding tests were conducted in sandstone and carbonate cores. The subject polymer gel was injected at rates typical of those in field applications. The injectivity of PAM/PEI was tested in Berea sandstone cores with initial permeability of ~45 mD. The post‐treatment of the system showed a permeability reduction of ~94% for a period of two weeks. The injectivity in low permeability carbonate cores required more retardation compared with the injectivity in sandstone cores. The gel reduced the permeability to brine in Indiana limestone core by 99.8% for more than 5 months. Rheology of cured gel samples indicated that the gel strength needs about one day of curing in the core for the strength to stabilize. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41869. 相似文献
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Hussein Saad Amr Mohamed Tamer ElBatt 《Wireless Communications and Mobile Computing》2015,15(15):1929-1944
In this paper, we address the problem of distributed interference management of femtocells that share the same frequency band with macrocells using distributed multi‐agent Q‐learning. We formulate and solve two problems representing two different Q‐learning algorithms, namely, femto‐based distributed and sub‐carrier‐based distributed power controls using Q‐learning (FBDPC‐Q and SBDPC‐Q). FBDPC‐Q is a multi‐agent algorithm that works on a global basis, for example, deals with the aggregate macrocell and femtocell capacities. Its complexity increases exponentially with the number of sub‐carriers in the system. Also, it does not take into consideration the sub‐carrier macrocell capacity as a constraint. To overcome these problems, SBDPC‐Q is proposed, which is a multi‐agent algorithm that works on a sub‐carrier basis, for example, sub‐carrier macrocell and femtocell capacities. Each of FBDPC‐Q and SBDPC‐Q works in three different learning paradigms: independent (IL), cooperative (CL), and weighted cooperative (WCL). IL is considered the simplest form for applying Q‐learning in multi‐agent scenarios, where all the femtocells learn independently. CL and WCL are the proposed schemes in which femtocells share partial information during the learning process in order to strike a balance between practical relevance and performance. We prove the convergence of the CL paradigm when used in the FBDPC‐Q algorithm. We show via simulations that the CL paradigm outperforms the IL paradigm in terms of the aggregate femtocell capacity, especially in networks with large number of femtocells and large number of power levels. In addition, we propose WCL to address the CL limitations. Finally, we evaluate the robustness and scalability of both FBDPC‐Q and SBDPC‐Q, against several typical dynamics of plausible wireless scenarios (fading, path loss, random activity of femtocells, etc.). We show that the CL paradigm is the most scalable to large number of femtocells and robust to the network dynamics compared with the IL and WCL paradigms. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
50.
Production of lipid from depolymerised lignocellulose using the biocontrol yeast,Rhodotorula minuta: The fatty acid profile remains stable irrespective of environmental conditions
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