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111.
The authors investigated the effectiveness and specificity of the Penn Resiliency Program (PRP; J. E. Gillham, L. H. Jaycox, K. J. Reivich, M. E. P. Seligman, & T. Silver, 1990), a cognitive-behavioral depression prevention program. Children (N = 697) from 3 middle schools were randomly assigned to PRP, Control (CON), or the Penn Enhancement Program (PEP; K. J. Reivich, 1996; A. J. Shatté, 1997), an alternate intervention that controls for nonspecific intervention ingredients. Children's depressive symptoms were assessed through 3 years of follow-up. There was no intervention effect on average levels of depressive symptoms in the full sample. Findings varied by school. In 2 schools, PRP significantly reduced depressive symptoms across the follow-up relative to both CON and PEP. In the 3rd school, PRP did not prevent depressive symptoms. The authors discuss the findings in relation to previous research on PRP and the dissemination of prevention programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
112.
The conserved VPS13 proteins constitute a new family of lipid transporters at membrane contact sites. These large proteins are suspected to bridge membranes and form a direct channel for lipid transport between organelles. Mutations in the 4 human homologs (VPS13A–D) are associated with a number of neurological disorders, but little is known about their precise functions or the relevant contact sites affected in disease. In contrast, yeast has a single Vps13 protein which is recruited to multiple organelles and contact sites. The yeast model system has proved useful for studying the function of Vps13 at different organelles and identifying the localization determinants responsible for its membrane targeting. In this review we describe recent advances in our understanding of VPS13 proteins with a focus on yeast research.  相似文献   
113.
The Theory of Planned Behaviour (TPB) plus moral norms, anticipated regret, past behaviour, self-identity and perceived susceptibility was applied to predicting motorcyclists’ intention to ride above the speed limit and ride at inappropriate speeds. Past behaviour, control beliefs, attitudes, moral norm, normative beliefs, age and self-identity explained 60% of the variance in motorcyclists’ intention to exceed the speed limit on motorways (N = 1381). A total of 62% of the variance in motorcyclists’ intention to really go for it on rural roads was accounted for, with past behaviour, attitudes, control beliefs, age, normative beliefs, anticipated regret, self-identity, behavioural beliefs and training status being significant (N = 1116). Finally, attitudes, past behaviour, control beliefs, moral norm, anticipated regret, behavioural beliefs, normative beliefs, engine size and self-identity explained 57% of the variance in motorcyclists’ intention to ride faster than felt safe in order to keep up with the group (N = 1940). The belief-based measures also successfully differentiated between those who intended to speed and those who did not. Theoretical and practical implications of the findings are discussed.  相似文献   
114.
Microgravity is potentially a powerful tool for investigating processes that are sensitive to the presence of solid walls, since fluid containment can be achieved by surface tension. One such process is the transformation of protein in solution into amyloid fibrils; these are protein aggregates associated with neurodegenerative diseases such as Alzheimer’s and Parkinson’s. In addition to solid walls, experiments with gravity are also subject to influences from sedimentation of aggregates and buoyancy-driven convection. The ring-sheared drop (RSD) module is a flow apparatus currently under development to study formation of amyloid fibrils aboard the International Space Station (ISS). A 25 mm diameter drop of protein solution will be contained by surface tension and constrained by a pair of sharp-edged tubes, forming two contact rings. Shear can be imparted by rotating one ring with the other ring kept stationary. Here we report on parabolic flights conducted to test the growth and pinning of 10 mm diameter drops of water in under 10 s of microgravity. Finite element method (FEM) based fluid dynamics computations using a commercial package (COMSOL) assisted in the design of the parabolic flight experiments. Prior to the parabolic flights, the code was validated against experiments in the lab (1 g), on the growth of sessile and pendant droplets. The simulations show good agreement with the experiments. This modeling capability will enable the development of the RSD at the 25 mm scale for the ISS.  相似文献   
115.
A 12 week study was conducted on the egg albumen from both pasteurized and non-pasteurized shell eggs using visible-near infrared spectroscopy. Prediction models of the chemical changes detected in the spectra to the measurement of Haugh units (measure of interior egg quality) were calculated using principal component regression analysis. Additionally, the study sought to determine how pasteurization affects both shelf life and egg quality. 84 dozen eggs were involved in this study, with 12 dozen eggs scanned initially and biweekly for the remainder of the study. Eggs were stored at 4 °C throughout the study. Haugh unit measurements were conducted followed by the visible/near infrared spectra of the albumen. The changes in the spectra over the 12 week period were very subtle and consisted mainly of an approximately 10 % decrease in transmission across the 400–1,200 nm range. The 400–550 nm region can be used to distinguish between the spectra of control eggs and pasteurized eggs. The results suggest that spectral data can be used to confirm and/or predict the storage time of eggs. The correlation coefficients of the spectra models for storage time are 0.97 and 0.98 for the control (untreated) and pasteurized eggs, respectively. Correlation values for predicting Haugh units from the spectra of the samples resulted in less useful predictive models in this study, especially for pasteurized samples.  相似文献   
116.
The objective of this study was to obtain and characterise curcumin‐loaded proliposomes by the method of coating of micronised sucrose. Proliposomes incorporating curcumin were characterised in terms of coating, morphology, crystallinity, solubility and water sorption. The powders showed a good capacity to preserve curcumin, as after 60 days of storage about 80% of the initial amount of curcumin was preserved. The water adsorption on the proliposomes was very low, as was the hygroscopicity (3.4%). The evaluation of the capacity of the multilamellar liposomes produced by the hydration of phospholipid powders to preserve encapsulated curcumin was assessed. Liposome dispersions were produced with different thickeners, and the best results of average size (around 800 nm) and curcumin preservation (72% after 30 days of storage) were obtained with xanthan gum and guar gum. These results evidenced the coating of micronised sucrose is a promising technique to produce liposomes to be incorporated into food.  相似文献   
117.
118.
A series of copoly(imide alkyl ether)s were synthesized to explore surface migration of fluorinated alkyl ether blocks (AEFO)s. Mechanical and surface properties of solution cast, thermally imidized films were determined. Incorporation of the AEFO oligomers at loading levels up to 5 wt % resulted in a slight decrease (usually less than 10%) in tensile modulus. Surface migration of the AEFOs raised the advancing water contact angle from approximately 80° to above 95° for the copolymer systems. The composition at which addition of more AEFO further increased water contact angle values was related to the number of fluorine atoms in the perfluorinated side chains. Surface excess concentration of the AEFO at different loading levels was calculated from X‐ray photoelectron spectroscopy results. At higher AEFO loading levels, the surface excess concentration was relatively constant suggesting formation of stable structures within the bulk similar to micelle formation in surfactant solutions. Based on these results, it was determined that surface saturation occurred with the fluorinated AEFO species at loading levels as low as 1 wt % engendering changes in surface properties while retaining the bulk imide properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41538.  相似文献   
119.
The performance of a novel, transmission‐mode, portable, Fourier transform infrared (FTIR) analyzer was evaluated and compared to that of a benchtop attenuated total reflection (ATR)‐FTIR spectrometer. The total concentration of trans fatty acids in the fat extracted from 19 representative fast foods was rapidly (<5 min) quantified in a single measurement after conversion to fatty acid methyl esters (FAME). While the FTIR determination is rapid, the time required for extraction and derivatization is not. For all extracts, the total trans FAME concentration varied from approximately 0.5 to 11 % (of total FAME) as determined using the portable FTIR analyzer. The trans fat contents (mean ± SD), expressed in grams per serving and calculated on the basis of total fat content and FTIR determination of trans fat content, were found to be 1.00 ± 0.42 for hamburgers, 0.67 ± 0.78 for chicken tenders, 1.00 ± 1.24 for French fries, and 0.27 ± 0.23 for apple pies. Determinations of total trans‐unsaturated FAME were consistent with those obtained by use of ATR‐FTIR and GC official methods (AOCS Cd 14e‐09 and AOCS Ce 1j‐07, respectively). These results indicate that the portable FTIR analyzer is suitable for the rapid and routine quantification of total trans fat measured as FAME prepared from fats extracted from fast foods.  相似文献   
120.
Zirconium umbite, K2ZrSi3O9·H2O, is a microporous framework ion exchanger whose potential as a carrier for Zn2+ ions in antimicrobial formulations has not yet been investigated. Accordingly, batch Zn2+-exchange kinetics of synthetic zirconium umbite (K-UM) and the subsequent antimicrobial action of the zinc-bearing phase (Zn-UM) against Staphylococcus aureus and Escherichia coli are reported. Nonstoicheiometric over-exchange of Zn2+ for K+ was observed and attributed to hydrolysis and complexation reactions of Zn2+ within the umbite framework. The exchange process, which was described by a simple pseudo-first-order model (k 1 = 2.69 × 10−4 min−1, R 2 = 0.992), did not achieve equilibrium within 120 h at 25 °C, by which time the uptake of zinc was found to be 1.04 mmol g−1. The minimal bactericidal concentrations of Zn-UM for E. coli and S. aureus were found to be >10 g cm3 and <1.0 g cm3, respectively.  相似文献   
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