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21.
Today, many procedures for assessing the indoor environment rely on both subjective and objective indicators (e.g. ANSI/ASHRAE 55-2004; ISO 10551). It is however unclear how these two types of measurements are related to perceived comfort. This article aims at assessing the relative utility of subjective (rating scale measures) and objective indicators of perceived comfort of indoor environments. In a hospital setting, physical environmental variables (e.g. temperature, relative humidity and noise level) were simultaneously measured as respondents (both patients and staff) rated their perception of the indoor environment. Regression analyses indicated that the subjective sensory ratings were significantly better than objective indicators at predicting overall rated indoor comfort. These results are discussed in relation to existing measurement procedures and standards.  相似文献   
22.
During early-stage drug development, drug and metabolite distribution studies are carried out in animal tissues using a range of techniques, particularly whole body autoradiography (WBA). While widely employed, WBA has a number of limitations, including the following: expensive synthesis of radiolabeled drugs and analyte specificity and identification. WBA only images the radiolabel. MALDI MSI has been shown previously to be advantageous for imaging the distribution of a range of drugs and metabolites in whole body sections. Ion mobility separation (IMS) adds a further separation step to imaging experiments; demonstrated here is MALDI-IMS-MS whole body imaging of rats dosed at 6 mg/kg i.v. with an anticancer drug, vinblastine and shown is the distribution of the precursor ion m/z 811.4 and several product ions including m/z 793, 751, 733, 719, 691, 649, 524, and 355. The distribution of vinblastine within the ventricles of the brain is also depicted. Clearly demonstrated in these data are the removal of interfering isobaric ions within the images of m/z 811.4 and also of the transition m/z 811-751, resulting in a higher confidence in the imaging data. Within this work, IMS has shown to be advantageous in both MS and MS/MS imaging experiments by separating vinblastine from an endogenous isobaric lipid.  相似文献   
23.
Reviews of stream monitoring data suggest that there has been significant acidification (>1.0 pH unit at some sites) of Victorian streamwaters over the past 3 decades. To assess whether these declines are within the range of natural variability, we developed a diatom model for inferring past pH and applied it to a ca. 3500-yr diatom record from a flood plain lake, Callemondah 1 Billabong, on the Goulburn River, which has among the most substantial observed pH declines. The model has a jackkniffed r2 between diatom inferred and measured pH of 0.77 and a root mean square error of prediction of 0.35 pH units. In the pre-European period, pH was stable (range 6.5-6.7) for approximately 3000 yr. Since European settlement around 160 yr ago, diatom-inferred billabong pH has increased significantly by >0.5 units. We hypothesize that this increase in pH is related to processes associated with land clearance (e.g., increased base cation load and decreased organic acid load). There is no evidence of the recent monitored declines in the Callemondah record, which may indicate that that flood plain lakes and the main stream are experiencing divergent pH trends or that the temporal resolution in the billabong sediment record is insufficient to register recent declines.  相似文献   
24.
Females who have been sexually abused in childhood are at significantly higher risk to be revictimized in adolescence and adulthood. Revictimization is associated with a raft of adverse mental and physical health outcomes, and so understanding why victims of childhood sexual abuse are more vulnerable to later sexual assaults has critical implications for their development. It has been hypothesized that sexual abuse in childhood results in reduced ability to recognize and/or respond effectively to sexual threats later in life, but studies examining these ideas have produced inconsistent results. Further, this research has failed to incorporate the powerful physiological reaction elicited by threats of imminent harm to the self, which has the potential to disrupt cognitive processing and coping behavior. In the present paper, we propose a model of revictimization that integrates contemporary theory and research on the biological stress response with cognitive, affective, and behavioral factors believed to be involved in adaptive responding to sexual threats. The model provides a conceptual guide for understanding why females with a history of sexual abuse are more vulnerable to revictimization and offers ideas for improving prevention programs designed to strengthen females' ability to resist sexual coercion. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
25.

Purpose

To describe a ranked symptoms scale (RSS) discriminating subjective responses in contact lens (CL) wear in various situations.

Method

Forty experienced clinical trial participants were interviewed for their perceptions of ocular comfort scales, resulting in a numerical RSS. For further evaluation, 20 CL wearers enrolled into a prospective, randomised, crossover trial. Two silicone-hydrogel CLs and a lens care solution (LCS) [Combinations A & B] were selected based on prior performance identifying best/worst combinations for end-of-day comfort. The RSS and a numerical rating scale (NRS) were administered at two time-points (insertion/removal) on alternating days for 6 days.

Results

Both NRS and RSS showed acceptable internal consistency for comfort, vision and handling (Cronbach alpha = 0.71 for both scales) and similar repeatability for comfort and handling (coefficients-of-repeatability within 0.1 and 0.2 units, respectively, for each scale). The NRS and RSS discriminated differences between combinations for comfort (p  0.031) and vision (p  0.026) at both time-points. Additionally, the RSS showed lens/edge awareness influenced discomfort the most, ranking higher at insertion (p = 0.038) and higher for Combination-B at both time-points (p  0.002). Symptoms of dryness and tired eyes increased for both combinations at removal (p < 0.02). The RSS also showed haziness and blurred distance vision influenced vision dissatisfaction with Combination-B at lens removal (p  0.038) while eye strain/headache increased for both combinations by time of removal (p  0.013).

Conclusions

The RSS is able to discriminate subjective responses between combinations and time-of-day. The RSS’s ability to rank symptoms may be a useful tool in understanding perceptions of discomfort or dissatisfaction with CL wear.  相似文献   
26.
C4-substituted fluoroprolines (4R)-fluoroproline ((4R)-Flp) and (4S)-fluoroproline ((4S)-Flp) have been used in protein engineering to enhance the thermodynamic stability of peptides and proteins. The electron-withdrawing effect of fluorine can bias the pucker of the pyrrolidine ring, influence the conformational preference of the preceding peptide bond, and can accelerate the cis/trans prolyl peptide bond isomerisation by diminishing its double bond character. The role of 4,4-difluoroproline (Dfp) in the acceleration of the refolding rate of globular proteins bearing a proline (Pro) residue in the cis conformation in the native state remains elusive. Moreover, the impact of Dfp on the thermodynamic stability and bioactivity of globular proteins has been seldom described. In this study, we show that the incorporation of Dfp caused a redox state dependent and position dependent destabilisation of the thioredoxin (Trx) fold, while the catalytic activities of the modified proteins remained unchanged. The Pro to Dfp substitution at the conserved cisPro76 in the thioredoxin variant Trx1P did not elicited acceleration of the rate-limiting trans-to-cis isomerization of the Ile75-Pro76 peptide bond. Our results show that pucker preferences in the context of a tertiary structure could play a major role in protein folding, thus overtaking the rules determined for cis/trans isomerisation barriers determined in model peptides.  相似文献   
27.
Feed efficiency and energy balance are important traits underpinning profitability and environmental sustainability in animal production. They are complex traits, and our understanding of their underlying biology is currently limited. One measure of feed efficiency is residual feed intake (RFI), which is the difference between actual and predicted intake. Variation in RFI among individuals is attributable to the metabolic efficiency of energy utilization. High RFI (H_RFI) animals require more energy per unit of weight gain or milk produced compared with low RFI (L_RFI) animals. Energy balance (EB) is a closely related trait calculated very similarly to RFI. Cellular energy metabolism in mitochondria involves mitochondrial protein (MiP) encoded by both nuclear (NuMiP) and mitochondrial (MtMiP) genomes. We hypothesized that MiP genes are differentially expressed (DE) between H_RFI and L_RFI animal groups and similarly between negative and positive EB groups. Our study aimed to characterize MiP gene expression in white blood cells of H_RFI and L_RFI cows using RNA sequencing to identify genes and biological pathways associated with feed efficiency in dairy cattle. We used the top and bottom 14 cows ranked for RFI and EB out of 109 animals as H_RFI and L_RFI, and positive and negative EB groups, respectively. The gene expression counts across all nuclear and mitochondrial genes for animals in each group were used for differential gene expression analyses, weighted gene correlation network analysis, functional enrichment, and identification of hub genes. Out of 244 DE genes between RFI groups, 38 were MiP genes. The DE genes were enriched for the oxidative phosphorylation (OXPHOS) and ribosome pathways. The DE MiP genes were underexpressed in L_RFI (and negative EB) compared with the H_RFI (and positive EB) groups, suggestive of reduced mitochondrial activity in the L_RFI group. None of the MtMiP genes were among the DE MiP genes between the groups, which suggests a non-rate limiting role of MtMiP genes in feed efficiency and warrants further investigation. The role of MiP, particularly the NuMiP and OXPHOS pathways in RFI, was also supported by our gene correlation network analysis and the hub gene identification. We validated the findings in an independent data set. Overall, our study suggested that differences in feed efficiency in dairy cows may be linked to differences in cellular energy demand. This study broadens our knowledge of the biology of feed efficiency in dairy cattle.  相似文献   
28.
29.
Book reviews     

Foley, James D., van Dam, Andrles, Feiner, Steven K., and Hughes, John. Computer Graphics: Principles and Practice (2nd Ed.), Reading, MA: Addison‐Wesley (1990), pp. 1774. $59.95 (U.S. dollars), ISBN 0–201–12110–7.

Berry, Dianne and Hart, Anna (Eds.). Expert Systems: Human Issues. Cambridge, MA: MIT Press (1990), pp. 263. $35.00 (U.S. dollars), ISBN 0–262–02307–5.  相似文献   
30.
Abstract

A major initiative of the Sandia National Laboratories Technical Library is to provide desktop access to information for Sandia researchers. During 1995 the Library created a home page, with information about how to link to its client-server based OPAC. Through multiple access points Sandians can now search the catalog from their desks. A new and evolving initiative within Sandia Laboratories is to improve desktop access to Sandia-generated documents (full-text) by converting them to electronic form, placing them on Sandia's “internal Web,” and linking them to the OPAC bibliographic record, enabling desktop viewing and printing. This paper addresses the processes developed in the Library to accomplish the preceding activities. It also addresses procedures for cataloging these electronic reports, including identification of the bibliographic information and MARC tags to be used. Open issues and lessons learned are identified.  相似文献   
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