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101.
102.
Photovoltaic (PV) panel temperature plays a vital role in the performance of PV panels. When PV temperature increases, the electrical power and efficiency decrease. In the present study, a simple simulated model is derived and implemented for a 70‐W finned PV panel and the results are compared with those for a reference (unfinned) PV panel. The effect of various parameters including fin diameter, fin height, ambient temperature, fin coverage‐to‐area ratio, and solar irradiance level on PV performance are examined. It is concluded that more electrical power is generated under moving air than under still air conditions as solar irradiance increases. The optimum values for fin diameter, fin height, and fin coverage‐to‐area ratio are 0.005 m, 0.25 m, and 50%, respectively. The maximum simulated power difference between the finned and unfinned PV panels is 5 W under realistic weather conditions. The amount of power generated during the summer season would be about 3.32 kW·h greater than that by the reference PV panel over the same period. The root square percent deviation values between the results of the proposed model and previously published experimental data for panel temperature, electrical power, and electrical efficiency are 3.36%, 5.26%, and 5.48%, respectively.  相似文献   
103.
Encapsulation of Ganciclovir in lipophilic vesicular structure may be expected to enhance the oral absorption and prolong the existence of the drug in the systemic circulation. So the purpose of the present study was to improve the oral bioavailability of Ganciclovir by preparing nanosized niosomal dispersion. Niosomes were prepared from Span40, Span60, and Cholesterol in the molar ratio of 1:1, 2:1, 3:1, and 3:2 using reverse evaporation method. The developed niosomal dispersions were characterized for entrapment efficiency, size, shape, in vitro drug release, release kinetic study, and in vivo performance. Optimized formulation (NG8; Span60:Cholesterol 3:2 molar ratio) has shown a significantly high encapsulation of Ganciclovir (89±2.13%) with vesicle size of 144±3.47 nm (polydispersity index [PDI]=0.08). The in vitro release study signifies sustained release profile of niosomal dispersions. Release profile of prepared formulations have shown that more than 85.2±0.015% drug was released in 24 h with zero-order release kinetics. The results obtained also revealed that the types of surfactant and Cholesterol content ratio altered the entrapment efficiency, size, and drug release rate from niosomes. In vivo study on rats reveals five-time increment in bioavailability of Ganciclovir after oral administration of optimized formulation (NG8) as compared with tablet. The effective drug concentration (>0.69 μg/mL in plasma) was also maintained for at least 8 h on administration of the niosomal formulation. In conclusion, niosomes can be proposed as a potential oral delivery system for the effective delivery of Ganciclovir.  相似文献   
104.
The evaluated spectroscopic data are presented for known nuclides of mass 78 (Ni,Cu,Zn,Ga,Ge,As,Se,Br,Kr,Rb,Sr,Y,Zr). Excited-state data are nonexistent for 78Ni, 78Cu and 78Zr. For 78Zr, only the isotopic identification is established without any knowledge of its half-life and decay modes. Only limited excited state data exist for 78Y. The radioactive decays of the following isotopes are not considered by the evaluators as well established: 78Cu, 78mRb, 78Sr and 78Y. High-spin excitations are known for 78As, 78Se, 78Br, 78Kr, 78Rb and 78Sr. Significant amounts of new data have been added since the last NDS publication of A = 78 evaluation more than 18 years ago.This work supersedes earlier full evaluations of A = 78 published by 1981Si13 and 1975Ru01 and the one published in ‘update’ mode by 1991Ra06.  相似文献   
105.
106.
Objective: The conventional liposomal amphotericin B causes many unwanted side effects like blood disorder, nephrotoxicity, dose-dependent side effects, highly variable oral absorption and formulation-related instability. The objective of the present investigation was to develop cost-effective nanoemulsion as nanocarreir for enhanced and sustained delivery of amphotericin B into the skin.

Methods and characterizations: Different oil-in-water nanoemulsions were developed by varying the composition of hydrophilic (Tween® 80) surfactants and co-surfactant by the spontaneous titration method. The developed formulation were characterized, optimized, evaluated and compared for the skin permeation with commercial formulation (fungisome 0.01% w/w). Optimized formulations loaded with amphotericin B were screened using varied concentrations of surfactants and co-surfactants as decided by the ternary phase diagram.

Results and discussion: The maximum % transmittance obtained were 96.9?±?1.0%, 95.9?±?3.0% and 93.7?±?1.2% for the optimized formulations F-I, F-III and F-VI, respectively. These optimized nanoemulsions were subjected to thermodynamic stability study to get the most stable nanoemulsions (F-I). The results of the particle size and zeta potential value were found to be 67.32?±?0.8 nm and –3.7?±?1.2?mV for the final optimized nanoemulsion F-I supporting transparency and stable nanoemulsion for better skin permeation. The steady state transdermal flux for the formulations was observed between 5.89?±?2.06 and 18.02?±?4.3?µg/cm2/h whereas the maximum enhancement ratio were found 1.85- and 3.0-fold higher than fungisome and drug solution, respectively, for F-I. The results of the skin deposition study suggests that 231.37?±?3.6?µg/cm2 drug deposited from optimized nanoemulsion F-I and 2.11-fold higher enhancement ratio as compared to fungisome. Optimized surfactants and co-surfactant combination-mediated transport of the drug through the skin was also tried and the results were shown to have facilitated drug permeation and skin perturbation (SEM).

Conclusion: The combined results suggested that amphotericin B nanoemulsion could be a better option for localized topical drug delivery and have greater potential as an effective, efficient and safe approach.  相似文献   
107.
The dynamic and living characteristics of monolayers at the air-water interface of a cyclohexapeptide ( C6G ) and a cyclooctapeptide ( C8G ), both composed of glutamic acid and 3-aminobenzoic acid subunits in an alternating sequence, were investigated using the Langmuir balance technique, Brewster angle microscopy (BAM), and X-ray reflectivity (XR). An alanine-containing cyclohexapeptide ( C6A ) was included in this study for comparison. All three cyclopeptides preferentially adopt an orientation parallel to the subphase at low surface pressure. Continuous compression then causes the molecules to flip to a perpendicular state, thus minimizing their molecular area. In contrast to C8G and C6A , a pronounced hysteresis observed during the compression-expansion cycle of C6G indicates that strong intermolecular interactions between the cyclopeptide rings occur in the monolayers of this peptide. This result is supported by BAM measurements that show the formation of crystallite structures for C6G at high surface pressures, whereas no structures were observed for C8G and C6A . These results indicate that C6G is able to self-assemble upon surface compression, an ability that is obviously critically dependent on the correct ring size and composition of the peptide. The presence of hydrogen bond acceptors in the side chains of C6G suggests that the structural stabilization of the monolayer is due to H-bonding, possibly between ring NH groups and side chain CO groups. Our in situ study thus provides a detailed understanding of the molecular dynamics and uninterrupted interfacial behavior of the three peptides in a real-time frame.  相似文献   
108.
109.
Aegle marmelos, a plant indigenous to India has been used by the inhabitants of the Indian subcontinent for over 5000 years. The leaves, bark, roots, fruits and seeds are used extensively in the Indian traditional system of medicine the Ayurveda and in various folk medicine to treat myriad ailments. Bael fruits are of dietary use and the fruit pulp is used to prepare delicacies like murabba, puddings and juice. Bael fruits are also used in the treatment of chronic diarrhea, dysentery, and peptic ulcers, as a laxative and to recuperate from respiratory affections in various folk medicines. Scientific studies have validated many of the ethnomedicinal uses and reports indicate that the fruit possesses broad range of therapeutic effects that includes free radical scavenging, antioxidant, inhibition of lipid peroxidation, antibacterial, antiviral, anti-diarrheal, gastroprotective, anti-ulcerative colitis, hepatoprotective, anti-diabetic, cardioprotective and radioprotective effects. For the first time, this review critically assesses the nutritional values, phytochemistry and preclinical pharmacological properties of the bael fruit. Attempts are also made at emphasizing the dietary and pharmaceutical potential of bael fruit that has been largely underutilized and neglected.  相似文献   
110.
The functional and nutraceutical importance of various foods is often attributed to the bioactive molecules present in them. A number of components have been studied but dietary fiber and its different constituents are of prime consideration. Among these, arabinoxylan (AX) and arabinogalactan (AG) are of significant importance in that they hold potential in improving the quality of the baked products along with providing health benefits against various ailments. However, the improvements are dependent on their molecular weights, cross linkages, and solubility. Water-Extractable Arabinoxylan (WEAX) is more effective as compared to Water-Unextractable Arabinoxylan (WUEAX). In this review article, efforts were directed to describe the structural and molecular conformations of these functional ingredients. The discussion has been made regarding the functional properties of AX and AG, for example, improvements in water absorption capacities, dough stability time, and viscosity. They also improve the baking absorption of flour that is positively correlated with bread volume, the most important criterion for stakeholders. The arguments are also provided on the detrimental effects on gluten quality with some possible solutions. Their role in improving the quality and extending the shelf life of bread by reducing the process of staling and retrogradation is the main idea presented in the article. The nutraceutical perspectives were also highlighted as they are helpful in regulating blood cholesterol which thereby protect the body from cardiovascular disorders like atherosclerosis. Additionally, they act as prebiotics for microorganisms residing in the gastrointestinal tract.  相似文献   
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