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1.
Recent studies by R. J. Ivnik et al (see record 1993-04116-001), J. F. Malec et al (see record 1993-04120-001), and J. J. Ryan et al (see record 1991-08835-001) have provided age-extended norms for the Wechsler Adult Intelligence Scale—Revised (WAIS—R). The current study compared IQ scores based on these newer age-extended norms in 216 elderly Alzheimer's disease (AD) patients. Results showed that when the norms from Ryan et al were used, IQ scores were consistently the same as or higher than when WAIS—R manual norms were used. When the norms provided by Ivnik et al and Malec et al were used, IQ scores tended to be lower than WAIS—R manual norms for younger patients with more intellectual impairment. Results illustrate the importance of reporting the normative sample upon which IQ test scores for older adults are based and provide guidelines for selecting which set of age-extended WAIS—R norms to use with cognitively impaired elderly Ss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
Previous research has shown multihue scales to be well‐suited to code categorical features and shown lightness scales to be well‐suited to code ordinal quantities. We introduce an algorithm, Motley, that produces color scales varying in both hue and lightness, intended to be effective for both categorical and ordinal coding, allowing users to determine both absolute and relative quantities efficiently and accurately. The algorithm first determines the lightnesses of scale colors to maximize perceived lightness differences and establish the lightness ordering, generating separate search spaces for each scale position. It then selects hues by heuristic search to maximize the discriminability of the scale. It produces scales that are ordered with respect to lightness but unordered with respect to hue and thus more discriminable than typical multihue lightness scales. In an experimental evaluation on human subjects, Motley's scales enabled accurate judgments of relative quantity, with response times superior to unordered multihue scales and comparable to ordered lightness scales, and enabled accuracy and speed of judgments of absolute quantity superior to lightness scales and comparable to multihue scales. Published 2009 Wiley Periodicals, Inc., Col Res Appl, 2010.  相似文献   
3.
The performance of a silicone-lubricated electrostatic clutch, as originally reported by Fitch [IBM J. Res. Develop. 61, No. 1 (1957)], differs considerably from that of one using dry surfaces or boundary lubricants. The study reported here, of constriction resistance and the dependence of the coefficient of friction on the bearing modulus (μ v/p), provides a qualitative and quantitative explanation of this behavior. The existence of an air film was experimentally observed for the first time. This film, occurring under proper speed and loading conditions, explains the low residual torque. Effects due to voltage, rotor surface speed, fluid viscosity, band width, and surface roughness are shown to exist and are discussed. The lubricating film thickness, determined by a radioactive tracer technique, is shown to depend on rotor surface speed and voltage.  相似文献   
4.
In an effort to decrease the high cost associated with the design, testing, and production of electrocatalysts, a completely electrochemical scheme has been developed to deposit and platinize a nanoporous Au (NPG) based catalyst for formic acid oxidation. The proposed route enables synthesis of an alternative to the most established, nanoparticles based catalysts and addresses issues of the latter associated with either contamination inherent from the synthetic route or poor adhesion to the supporting electrode. The synthetic protocol includes as a first step, electrochemical codeposition of a Au((1-x))Ag(x) alloy in a thiosulfate based electrolyte followed by selective electrochemical dissolution (dealloying) of Ag as the less noble metal, that generates an ultrathin and preferably continuous porous structure featuring thickness of less than 20 nm. NPG is then functionalized with Pt (no thicker than 1 nm) by surface limited redox replacement (SLRR) of underpotentially deposited Pb layer to form Pt-NPG. SLRR ensures complete coverage of the surface with Pt, believed to spread evenly over the NPG matrix. Testing of the catalyst at a proof-of-concept level demonstrates its high catalytic activity toward formic acid oxidation. Current densities of 40-50 mA cm(-2) and mass activities of 1-3 A.mg(-1) (of combined Pt-Au catalyst) have been observed and the Pt-NPG thin films have lasted over 2600 cycles in standard formic acid oxidation testing.  相似文献   
5.
Recent research indicates that by 4.5 months, infants use shape and size information as the basis for individuating objects but that it is not until 11.5 months that they use color information for this purpose. The present experiments investigated the extent to which infants' sensitivity to color information could be increased through select experiences. Five experiments were conducted with 10.5- and 9.5-month-olds. The results revealed that multimodal (visual and tactile), but not unimodal (visual only), exploration of the objects prior to the individuation task increased 10.5-month-olds' sensitivity to color differences. These results suggest that multisensory experience with objects facilitates infants' use of color information when individuating objects. In contrast, 9.5-month-olds did not benefit from the multisensory procedure; possible explanations for this finding are explored. Together, these results reveal how an everyday experience--combined visual and tactile exploration of objects--can promote infants' use of color information as the basis for individuating objects. More broadly, these results shed light on the nature of infants' object representations and the cognitive mechanisms that support infants' changing sensitivity to color differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
In this article, the authors review the literature regarding evidence-based psychological treatments (EBTs) for behavioral disturbances in older adults with dementia, as proposed by the American Psychological Association's Committee on Science and Practice of the Society for Clinical Psychology. Fifty-seven randomized clinical trials were reviewed for inclusion on the basis of titles or abstract information. Forty-three were excluded either because they did not meet EBT methodological criteria or because they involved environmental or psychoeducational nursing interventions in which the psychological component could not be separately evaluated. Fourteen studies were considered for inclusion as EBTs; of these, 8 showed significant differences between treatment and control groups. Results of this review indicate that behavioral problem-solving therapies that identify and modify antecedents and consequences of problem behaviors and increase pleasant events and individualized interventions based on progressively lowered stress threshold models that include problem solving and environmental modification meet EBT criteria. Additional randomized clinical trials are needed to evaluate the generalizability and efficacy of these and other promising psychological interventions in a variety of settings with individuals who have a range of cognitive, functional, and physical strengths and limitations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
Drinking water treatment and disinfection byproduct (DBP) research can be complicated by natural organic matter (NOM) temporal variability. NOM preservation by lyophilization (freeze-drying) has been long practiced to address this issue; however, its applicability for drinking water research has been limited because the selected NOM sources are atypical of most drinking water sources. The purpose of this research was to demonstrate that reconstituted NOM from a lyophilized reverse-osmosis (RO) concentrate of a typical drinking water source closely represents DBP formation in the original NOM. A preliminary experiment assessed DBP formation kinetics and yields in concentrated NOM, which demonstrated that chlorine decays faster in concentrate, in some cases leading to altered DBP speciation. Potential changes in NOM reactivity caused by lyophilization were evaluated by chlorination of lyophilized and reconstituted NOM, its parent RO concentrate, and the source water. Bromide lost during RO concentration was replaced by adding potassium bromide prior to chlorination. Although total measured DBP formation tended to decrease slightly and unidentified halogenated organic formation tended to increase slightly as a result of RO concentration, the changes associated with lyophilization were minor. In lyophilized NOM reconstituted back to source water TOC levels and then chlorinated, the concentrations of 19 of 21 measured DBPs, constituting 96% of the total identified DBP mass, were statistically indistinguishable from those in the chlorinated source water. Furthermore, the concentrations of 16 of 21 DBPs in lyophilized NOM reconstituted back to the RO concentrate TOC levels, constituting 86% DBP mass, were statistically indistinguishable from those in the RO concentrate. This study suggests that lyophilization can be used to preserve concentrated NOM without substantially altering the precursors to DBP formation.  相似文献   
8.
The adsorptive and catalytic characteristics of waste-reclaimed adsorbent (WR), which is a calcined mixture of bottom-ash and dredged-soil, was investigated for its application to treating BTEX contamination. BTEX adsorption in WR was 54%, 64%, 62%, and 65%, respectively, for a 72 h reaction time. Moreover, the catalytic characteristics of WR were observed when three types of oxidation systems (i.e., H(2)O(2), persulfate (PS), and H(2)O(2)/Fe(III)/oxalate) were tested, and these catalytic roles of WR could be due to iron oxide on its surface. In PS/WR system, large amounts of metal ions from WR were released because of large drops of solution pH, and the surface area of WR was also greatly reduced. Moreover, the BTEX that was removed per consumed oxidant (ΔC(rem)/ΔOx) increased with increasing PS. In H(2)O(2)/Fe(III)/oxalate with WR system, the highest BTEX degradation rate constants (k(deg)) were calculated as 0.338, 0.365, 0.500 and 0.716 h(-1), respectively, when 500 mM of H(2)O(2) was used, and the sorbed BTEX on the surface of WR was also degraded, which suggests the regeneration of WR. Therefore, the oxidant-injected permeable reactive barrier filled in WR could be an alternative to treating BTEX with both adsorption and catalytic degradation.  相似文献   
9.
A microfluidic Deans switch was used as a comprehensive two-dimensional gas chromatography (GCxGC) modulator. The simplicity and wide temperature range of the Deans switch make it a promising alternative to existing modulation techniques. However, the Deans switch is a low duty cycle modulator; that is, it samples only a small portion of the primary column effluent. Like all low duty cycle modulators, the Deans switch produces inconsistent transfer of components from the primary to the secondary column if the primary peaks are undersampled. Theoretical simulations and experimental studies show that the relative standard deviation (RSD) of the fraction of material transferred from the primary column to the secondary column is less than 1% if the modulation ratio is greater than 2.5. But the RSDs increase rapidly as the modulation ratio is decreased below 2.5. Deans switch GCxGC was validated by analyzing the aromatic content of gasoline. A fast analysis (<10 min) produced narrow primary peaks and a modulation ratio of 1.7. The quantitative results were in good agreement with results obtained with differential flow modulation GCxGC and GC/MS, but the RSDs of single-component levels were approximately three times greater. The Deans switch modulator was also used for a slower gasoline analysis (33 min run time) that produced modulation ratios near 5. In this case, the quantitative results and RSDs were in excellent agreement with the differential flow GCxGC and GC/MS results. These studies demonstrate that a Deans switch can be an effective modulator provided that modulation ratios greater than approximately 2.5 are employed.  相似文献   
10.
OBJECTIVE: The antenatal and intrapartum management of women with autoimmune thrombocytopenia is controversial. The current approach emphasizes an effort to identify maternal characteristics predictive of severe neonatal thrombocytopenia or to measure fetal platelet counts and perform cesarean section in patients considered to be at risk for neonatal intracranial hemorrhage. In the current study we review our experience with maternal autoimmune thrombocytopenia and neonatal outcome. STUDY DESIGN: Fifty-five pregnancies with autoimmune thrombocytopenia over a 10-year period in three major medical centers in San Diego, California, were evaluated. Maternal characteristics and neonatal outcomes were assessed and compared with those in other recent reports. Data were submitted to Fisher's exact (two-tailed), chi2, and Student t tests, with linear regression performed to analyze the association between variables. RESULTS: Maternal characteristics including platelet count, presence of antiplatelet antibody, antecedent history of autoimmune thrombocytopenia, and corticosteroid therapy were not predictive of severe neonatal thrombocytopenia. Maternal history of splenectomy was significantly correlated with fetal platelet counts <50 x 10(9)/L (odds ratio 5.63; 95% confidence interval 2.2 to 14.3). There were four neonates with severe neonatal thrombocytopenia (8%), and one who was delivered by cesarean section had intracranial hemorrhage. CONCLUSIONS: These findings, combined with others in the literature, confirm that severe neonatal thrombocytopenia is an infrequent complication of maternal autoimmune thrombocytopenia and is not reliably predicted by maternal characteristics. Intracranial hemorrhage is also a rare event and is not related to mode of delivery. Cesarean section should be reserved for obstetric indications only.  相似文献   
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