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71.
Purpose: Determinants of self-efficacy related to food preparation using store-bought food were examined in women belonging to the Atikamekw Nation. Also examined was whether self-efficacy was associated with household food insecurity. Methods: A cross-sectional survey was conducted with 107 women responsible for household food supplies. Two self-efficacy scores were calculated, one for healthy food preparation and one for food preparation in general. Household food insecurity was measured with an adapted version of the United States Food Security Core Module. The other variables were household composition, income sources, food supplies, tobacco use, participants' health status, and lifestyle and sociodemographic characteristics. Multiple linear regression was used to analyze associations between self-efficacy and household food insecurity in 99 participants. Results: Severe household food insecurity was associated with significantly lower healthy food preparation scores in Atikamekw women. Other associated variables were food supplies, marital status, alcohol consumption, weight status, and understanding of the native language. Conclusions: Application of the concept of self-efficacy contributes to a better understanding of the factors influencing food preparation in Atikamekw women. In this study, self-efficacy in healthy food preparation was linked to food insecurity and obesity, particularly in the most serious cases. Efforts to improve diet will require not only behavioural interventions, but public policies.  相似文献   
72.
In this study, the effects of fiber surface modification and hybrid fiber composition on the properties of the composites is presented. Jute fibers are cellulose rich (>65%) modified by alkali treatment, while the lignin rich (>40%) coconut coir fibers consist in creating quinones by oxidation with sodium chlorite in the lignin portions of fiber and react them with furfuryl alcohol (FA) to create a coating around the fiber more compatible with the epoxy resins used to prepare polymer composites. The maximum improvement on the properties was achieved for the hybrid composite containing the jute–coir content of 50 : 50. The tensile and flexural strength are recorded as 25 and 63 MPa at modified coir fiber content of 50 vol %, respectively, which are 78% and 61% higher than those obtained for unmodified fiber reinforced composites, i.e., tensile and flexural strength are 14 and 39 MPa, respectively. The reinforcement of the modified fiber was significantly enhanced the thermal stability of the composites. SEM features correlated satisfactorily with the mechanical properties of modified fiber reinforced hybrid composites. SEM analysis and water absorption measurements have confirmed the FA-grafting and shown a better compatibility at the interface between chemically modified fiber bundles and epoxy novolac resin. Hailwood–Horrobin model was used to predict the moisture sorption behavior of the hybrid composite systems. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
73.
The Magnetic Reynolds Number (MRN) in neon is computed as a function of Neon shock speed. The magnetic field profiles at various positions in the axial run down phase of the INTI Plasma Focus device are measured over a range of pressures from 2 to 20 Torr. These profiles are assessed for good electromagnetic coupling including measuring the current per unit current sheet thickness as a comparative measure of current sheet diffusion. It was found that at an axial current sheet speed of over 3.5 cm/μs (corresponding to MRN > 15), the current sheet has a compact profile with current density of 55 kA/cm of sheet thickness whereas at speeds below 2.8 cm/μs (corresponding to MRN < 10) the profile is more diffuse with current density less than 30 kA/cm of sheet thickness. Based on these studies it is proposed to take a speed of 3 cm/μs corresponding to an MRN of 10 as the minimum speed of neon current sheet below which the electromagnetic coupling begins to weaken.  相似文献   
74.
Theory and empirical research suggest that perceived self-efficacy, or one's perceived ability to perform personally significant tasks, is related to individuals' psychological well-being and mental health. Thus, the authors hypothesized that bicultural individuals' perceived ability to function competently in 2 cultures, or perceived bicultural self-efficacy, would be related positively to their psychological well-being and mental health. Three studies were conducted to develop and validate a measure of perceived bicultural self-efficacy and to explore its relationships with indices of psychological well-being and mental health. Exploratory (n = 268) and confirmatory (n = 164) factor analyses on the theoretically derived Bicultural Self-Efficacy Scale (BSES) items support a measurement model that taps into the 6 dimensions of bicultural competence proposed by T. LaFromboise, H. L. K. Coleman, and J. Gerton (1993). Furthermore, initial evidence for internal consistency (Studies 1, 2, and 3) and test–retest reliability (n = 51 Asian Americans) for each of the 6 subscales were found. Finally, perceived bicultural self-efficacy was found to be related to bicultural college students' psychological well-being and mental health. Research implications of the perceived bicultural self-efficacy construct and the potential utility of the BSES as a multidimensional measure of the construct are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
The present work reports the effect of bentonite clay on methane hydrate formation and dissociation in synthetic seawater of salinity 3.55 % of total dissolved salts. Extensive observations of pressure‐temperature equilibrium during formation and decomposition of methane hydrate under different conditions have been made. It is observed that phase equilibrium conditions of hydrate are affected on changing the concentration of bentonite clay in synthetic seawater. Induction time for hydrate nucleation has been measured under different concentrations of clay and subcooling conditions. The presence of bentonite clay in synthetic seawater reduces the induction time of hydrate formation. Enthalpy of hydrate dissociation is calculated by Clausius‐Clapeyron equation using measured phase equilibrium data. The amount of gas consumed during hydrate formation has been calculated using real gas equation. It is found that a larger amount of gas is consumed upon addition of bentonite clay in synthetic seawater.  相似文献   
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77.
The Meats Research Unit (MRU) methods, developed by MRU scientists of the U.S. Meat Animal Research Center, have been used to study the prevalence of Escherichia coli O157:H7 in cattle carcass, hide, and fecal samples. The sensitivity of these methods for recovery of injured E. coli O157:H7 cells from inoculated and uninoculated samples was determined, and potential improvements to these methods were evaluated. When using the conventional MRU methods, 91% of the pre-evisceration carcass samples tested positive for E. coli O157:H7 when inoculated with 5 to 10 CFU, 100% of hide samples tested positive for E. coli O157:H7 when inoculated with 30 to 50 CFU, and 96% of the fecal samples produced positive results when inoculated with 300 to 400 CFU per 10 g. The addition of a phosphate buffer to the tryptic soy broth enrichment improved recovery of E. coli O157:H7 from feces. Using the modified enrichment, 92% of the samples were identified as positive when inoculated with 10 to 30 CFU per 10 g. Substituting a commercially available wash buffer for the phosphate-buffered saline (PBS) plus Tween 20 wash buffer during immunomagnetic separation of hide samples improved recovery of the target organism at lower inoculum concentrations. When comparing uninoculated samples, substituting a PBS buffer plus a zwitterionic detergent for PBS plus Tween 20 also had a positive effect on recovery of E. coli O157:H7 from hide samples. Data presented here indicate that the MRU methods are highly effective at recovering injured E. coli O157:H7 from fecal, hide, and beef carcass samples; however, modifications can be added to increase the sensitivity.  相似文献   
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79.
Numerical experiments are carried out, using the Lee model code to compute the neutron yield Yn of PF1000 as a function of pressure. Computed results are compared with available published results of neutron yield. Relevant plasma focus properties such as peak discharge current Ipeak, pinch current Ipinch, pinch ion density ni and energy input into the pinch EINP are also discussed as functions of pressures so as to provide correlation of Yn with relevant plasma focus properties over the operational range of pressures.  相似文献   
80.
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