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51.
In this paper, the fuzzy eigenvalues and fuzzy eigenvectors of a fuzzy matrix have been found. To do this, the spreads are allocated to the obtained core from the corresponding crisp matrix which it makes a fuzzy number surely.  相似文献   
52.
Pyrolysis fuel oil cracking by low‐temperature plasma was investigated in a dielectric barrier discharge reactor at ambient pressure. The promoting effect of methane and ethane in the formation of products was evaluated by altering the working gas from methane to ethane. In addition, the production of hydrocarbons and hydrogen was analyzed. The main parameters were working gas type, flow rate, and applied voltage. Increasing the applied voltage enhanced the production rate of valuable petrochemical compounds like gas and liquid. Alteration of the working gas flow rate led to a higher production rate of H2, C2, C3, and C4. Chemical investigations were performed by optical emission spectroscopy of plasma and the main mechanisms are described.  相似文献   
53.
Previous studies have demonstrated improved nose-to-lung aerosol drug delivery with controlled condensational growth methods using a mixer-heater developed to synchronize aerosol delivery with patient inhalation. The goal of this study was to develop a new mixer-heater that delivers aerosols with a transient flow profile similar to a sinusoidal breathing waveform. The mixer-heater consisted of a chamber with two blowers delivering aerosol during the inhalation cycle of three sinusoidal breathing profiles. The effects of breathing profiles and mode of condensational growth delivery were studied using two in vitro extrathoracic airway models (closed- and open-mouth options). In excipient enhanced growth (EEG) delivery mode, increasing peak exhalation breathing flow rate decreased the emitted dose from the mixer-heater using the closed-mouth model. The mean (SD) emitted doses were 92 (2)%, 77 (2)%, and 70 (2)%, with 23, 35, and 44 L/min peak exhalation breathing flow rates, respectively. Using the in vitro open-mouth model mitigated the effect of breathing and the emitted doses were 93 (0.5)%, 83 (3)%, and 90 (4)% using the breathing profiles. The emitted doses in enhanced condensational growth (ECG) delivery mode using the breathing profiles with peak flow rates of 23, 35, and 44 L/min were 63 (4)%, 58 (2)%, and 58 (1)%, which were consistently lower than with EEG. Similarly, using the open-mouth model in ECG mode increased emitted doses to 77 (3)%, 73 (2)%, and 77 (8)%, respectively. The developed aerosol mixer-heater delivered greater than 50% of the nominal dose using a flow profile of sinusoidal inhalation, which represents a significant improvement compared to the current methods.

Copyright 2014 American Association for Aerosol Research  相似文献   

54.
Dynein is a ~1.2 MDa cytoskeletal motor protein that carries organelles via retrograde transport in eukaryotic cells. The motor protein belongs to the ATPase family of proteins associated with diverse cellular activities and plays a critical role in transporting cargoes to the minus end of the microtubules. The motor domain of dynein possesses a hexameric head, where ATP hydrolysis occurs. The presented work analyzes the structure–activity relationship (SAR) of dynapyrazole A and B, as well as ciliobrevin A and D, in their various protonated states and their 46 analogues for their binding in the AAA1 subunit, the leading ATP hydrolytic site of the motor domain. This study exploits in silico methods to look at the analogues’ effects on the functionally essential subsites of the motor domain of dynein 1, since no similar experimental structural data are available. Ciliobrevin and its analogues bind to the ATP motifs of the AAA1, namely, the walker-A (W-A) or P-loop, the walker-B (W-B), and the sensor I and II. Ciliobrevin A shows a better binding affinity than its D analogue. Although the double bond in ciliobrevin A and D was expected to decrease the ligand potency, they show a better affinity to the AAA1 binding site than dynapyrazole A and B, lacking the bond. In addition, protonation of the nitrogen atom in ciliobrevin A and D, as well as dynapyrazole A and B, at the N9 site of ciliobrevin and the N7 of the latter increased their binding affinity. Exploring ciliobrevin A geometrical configuration suggests the E isomer has a superior binding profile over the Z due to binding at the critical ATP motifs. Utilizing the refined structure of the motor domain obtained through protein conformational search in this study exhibits that Arg1852 of the yeast cytoplasmic dynein could involve in the “glutamate switch” mechanism in cytoplasmic dynein 1 in lieu of the conserved Asn in AAA+ protein family.  相似文献   
55.
One of the major themes in tissue engineering is scaffold fabrication. The porosity and pore size of scaffolds play a critical role in tissue engineering. Different methods are used to measure the porosity and pore size of scaffolds, although none can predict the cell infiltration for various cell sizes, shapes, and configurations. The aim of this study was to predict the cell infiltration of various cells with different sizes, shapes, and configurations through the use of image analysis. In this study, cell models were used to predict cell infiltration into nanofiber scaffolds. The results of this study showed that with increases in the cell size and the number of layers of nanofibers, the number of cells that could infiltrate the scaffolds decreased. In addition, the cell configuration had some effect on cell infiltration into the nanofiber scaffolds. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
56.
57.
In the present study, we developed aptamer (Apt) conjugated mesoporous silica nanoparticles (MSNs) for specific delivery of epirubicin (EPI) to breast cancer cells. MSNs were synthesized and functionalized with 3-mercaptopropyltrimethoxysilane (3-MPTMS), followed by MUC1 aptamer conjugation through disulfide bonds. The nanoparticles were analyzed by transmission electron microscopy (TEM), particle size analyzer, zeta potential, elemental analysis (CHNS), aptamer conjugation efficiency, drug loading efficiency, and drug release profile. Cell uptake and in vitro cytotoxicity of different formulations were performed. The results of MSNs characterization confirmed spherical nanoparticles with thiol functional groups. Particle size of obtained nanoparticles was 163?nm in deionized water. After conjugation of MUC1 aptamer and EPI loading (MSN-MUC1-EPI), particle size increased to 258?nm. The aptamer conjugation to MSNs with disulfide bonds were confirmed using gel retardation assay. Cellular uptake studies revealed better cell uptake of MSN-MUC1-EPI compared to MSN-EPI. Moreover, cytotoxicity study results in MCF7 cell lines showed improved cytotoxicity of MSN-MUC1-EPI in comparison with MSN-EPI or EPI at the same concentration of drug. These results exhibited that MSN-MUC1-EPI has the potential for targeted drug delivery into MUC1 positive breast cancer cells to improve drug efficacy and alleviate side effects.  相似文献   
58.
Water resources policy making often involves consideration of a broader scope of environmental, economic, and social issues. This inevitably complicates policy making since consensus among multiple stakeholders with different interests is needed to implement decisions. This work employs several practical and popular voting methods to solve a multi-stakeholder hydro-environmental management problem. Conventionally, voting methods or social choice rules have been applied for consensus development in small groups and elections. This work combines voting methods with a Monte-Carlo selection, in order to help with social choice making under uncertainty. This process is intended to aid decision-makers with understanding of the risks associated with potential decision alternatives. The Sacramento-San Joaquin Delta’s water export conflict is solved here as a benchmark problem to illustrate the proposed framework for social decision making and analysis under uncertainty.  相似文献   
59.
In this study, porous scaffolds made of polycaprolactone (PCL)/β-tricalcium phosphate (BTCP) biocomposite were fabricated for bone tissue engineering (BTE) applications. The microsphere-aggregated scaffolds were prepared with various BTCP concentrations (10wt%, 20wt%, 50wt%) by the freeze-drying method. The porosity of obtained microsphere-aggregated scaffolds with various pore sizes was 80–85%, where this value was about 70% for the PCL/BTCP (50) sample with no microsphere formation. The results indicated that adding BTCP has enhanced mechanical strength, and the mineralization of PCL/BTCP composite scaffolds has been increased compared to the pure PCL scaffolds in simulated body fluid (SBF). The adhesion and proliferation of mouse bone marrow mesenchymal stem cells (mMSCs) seeded onto PCL/BTCP scaffolds were enhanced compared to the PCL. In addition, in terms of differentiation, the incorporation of BTCP led to increasing the mineral deposition and alkaline phosphatase activity of mMSCs. The synergistic effect of using microsphere-aggregated scaffolds along with BTCP as a reinforcing agent in PCL biocomposite showed that these porous biocomposite scaffolds have the potential application in BTE.  相似文献   
60.
BACKGROUND: The bio‐oxidation of ferrous iron is a potential industrial process in the regeneration of ferric iron and the removal of H2S in combustible gases. Bio‐oxidation of ferrous iron may be an alternative method of producing ferric sulfate, which is a reagent used for removal of H2S from biogas, tail gas and in the pulp and paper industry. For practical use of this process, this study evaluated the optimal pH and initial ferric concentration. pH control looks like a key factor as it acts both on growth rate and on solubility of materials in the system. RESULTS: Process variables such as pH and amount of initial ferrous ions on oxidation by A. ferrooxidans and the effects of process variables dilution rate, initial concentrations of ferrous on oxidation of ferrous sulfate in the packed bed bioreactor were investigated. The optimum range of pH for the maximum growth of cells and effective bio‐oxidation of ferrous sulfate varied from 1.4 to 1.8. The maximum bio‐oxidation rate achieved was 0.3 g L?1 h?1 in a culture initially containing 19.5 g L?1 Fe2+ in the batch system. A maximum Fe2+ oxidation rate of 6.7 g L?1 h?1 was achieved at the dilution rate of 2 h?1, while no obvious precipitate was detected in the bioreactor. All experiments were carried out in shake flasks at 30 °C. CONCLUSION: The monolithic particles investigated in this study were found to be very suitable material for A. ferrooxidans immobilization for ferrous oxidation mainly because of its advantages over other commonly used substrates. In the monolithic bioreactor, the bio‐oxidation rate was 6.7 g L?1 h?1 and 7 g L?1 h?1 for 3.5 g L?1 and 6 g L?1 of initial ferrous concentration, respectively. For higher initial concentrations 16 g L?1 and 21.3 g L?1, bio‐oxidation rate were 0.9 g L?1 h?1 and 0.55 g L?1 h?1, respectively. Copyright © 2008 Society of Chemical Industry  相似文献   
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