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51.
In addition to two well‐recognized proteasome subtypes—constitutive proteasomes and immunoproteasomes—mounting evidence also suggests the existence of intermediate proteasome subtypes containing unconventional mixtures of catalytic subunits. Although they appear to play unique biological roles, the lack of practical methods for detecting distinct proteasome subtypes has limited functional investigations. Here, we report the development of activity‐based probes that crosslink two catalytic subunits within intact proteasome complexes. Identification of the crosslinked subunit pairs provides direct evidence of the catalytic subunit composition of proteasomes. Using these probes, we found that U266 multiple myeloma cells contain intermediate proteasomes comprising both β1i and β2, but not β1 and β2i, consistent with previous findings with other cell types. Our bifunctional probes can be utilized in functional investigations of distinct proteasome subtypes in various biological settings.  相似文献   
52.
Thermoduric bacteria (TDB), including sporeformers and their spores, can be present in milk and dairy products even after pasteurization. They have the potential to adversely affect the quality and shelf life of products. The objectives of this study were to identify the origin and common species of heat-resistant bacteria occurring during summer and winter on Midwest dairy farms. Bulk tank milk samples were taken from 10 dairy farms located along the South Dakota section of Interstate 29, with herd sizes ranging from 650 to 3,500 lactating dairy cows. Milk samples were profiled for the prevalence of TDB and spore counts (SC). Corn silage samples and swabs of the milking clusters were also taken at the dairies to further profile the potential sources of TDB and SC. The samples were taken 3 times during 2 seasons [winter (January–March) and summer (June–August)] to track seasonal changes in the farm bacterial flora. During winter, the average TDB counts in bulk tank milk were 2.61 log compared with 2.76 log TDB counts in the summer. The SC was 1.08 log in the winter, which was half the 2.06 log SC present in the summer season. Corn silage sampled in winter contained a 7.57 log TDB count compared with an increased 10.77 log TDB count during summer sampling. Concentrations of SC in corn silage reached an average of 6.3 log in winter compared with 11.81 log for summer. The seasonal effect was evident with an increase in summer counts across the board for TDB and SC, both in the feed and bulk tank milk samples. Bacillus licheniformis was the predominant species identified in 62.4% of winter (85 total) and 49.4% of summer (83 total) samples. Bacillus subtilis made up 9.4% of the remaining winter isolates, followed by Bacillus sonorensis at 8.2%. Conversely, B. sonorensis made up 12% of the summer isolates followed by Bacillus pumilus at 10.8%. Bacillus licheniformis is a ubiquitous microbe and was isolated from both TDB and sporeformer categories in all 3 sample types. There were larger increases in SC than TDB, indicating that summer temperatures and conditions may favor proliferation of sporeforming bacteria over that of TDB. In conclusion, samples from bulk tank milk, milking cluster swabs, and corn silage samples at each of the 10 sites indicated that B. licheniformis was the major contaminant species, regardless of season. In this experiment, corn silage was the major environmental source of both TDB and SC with higher concentrations in summer when compared with winter.  相似文献   
53.
A data acquisition program was written to allow independent triggering of multiple test sections of a thin flexible pavement. A total of 129 electronic sensors were installed in 17 test sections and subjected to 2,100 truck passes over several months immediately after construction. The measured strains were highly variable in the thin flexible pavement, but the program was still able to successfully trigger each section independently. The majority of signal processing was also performed within the program, which was written in Lab VIEW 7 Express. This approach significantly reduced the amount of postprocessing effort that would have otherwise been required. The quality of the triggering approach was compared to independently collected weigh in motion data. The majority of the test sections recorded within 0.5% of the number of vehicles recorded by the weigh in motion system. Key components of all major facets of the data acquisition and programming performed are discussed in detail.  相似文献   
54.
A framework is proposed for estimating the lifetime of wireless body area sensor network (WBASN) using probabilistic analysis and Monte Carlo simulation. WBASN implements real-time health monitoring by outfitting patients with wireless, wearable vital sign sensors. In health monitoring, the loss of critical or emergency information is a serious issue so there is a need to ensure quality of service. It is important to have an estimate of the lifetime of the network in order to replace or recharge the batteries because the loss of critical data is not acceptable. The lifetime of the WBASN is defined as the duration of time until the first node fails due to battery depletion. Heart rate and blood glucose are monitored at a central location in a managed health care environment for this evaluation of WBASN performance. A parametric model of a health monitoring network (HMN) is created with sets of random input distributions. Probabilistic analysis is used to determine the timing and distribution of node failure in the HMN.  相似文献   
55.
This paper is a summary report of the “Teamed Internships Program” (TIP), an Advanced Technological Education (ATE) grant through the National Science Foundation (NSF). This three‐year project created internships encompassing regional industries, federal research facilities, and two‐ and four‐year educational institutions. The project cultivated teamwork and communication skills for environmental technician and engineering students, developed instructional materials, and provided valuable contacts with industry. To foster faculty and teacher enhancement and student interest in environmental science and technology, insights from the program were incorporated into instructional materials and educational modules for dissemination to local secondary schools.  相似文献   
56.
Motivational assessment instruments typically measure clients' attributions about their readiness to change problem behaviors. They do not indicate why a client may be motivated to change, or provide guidance on how to retain an unmotivated client in treatment. The authors interviewed 415 substance abuse clients about their reasons for entering treatment and scored their responses along the dimensions of (a) negative versus positive treatment-entry pressures, (b) internal versus external sources of those pressures, and (c) the life domain from which the pressures emanated. Exploratory cluster analysis yielded 5 types of clients characterized by different profiles of perceived treatment-entry pressures. Cluster membership was predictive of treatment outcomes, and the clusters differed by demographic variables. These data support the discriminative and predictive utility of performing a multidimensional assessment of pressures to enter treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
57.
The present research contrasted theoretical models depicting the nature of the relation among drinking beliefs, drinking tendencies, and behavioral consequences in 266 incoming freshman college students. It also examined the theoretical relations between mother–teen communications and drinking beliefs relevant to behavioral consequences. The findings revealed direct relations between binge-drinking consequences and the drinking beliefs: Alcohol can make positive transformations, can enhance social behavior, and can increase negative affect and normative approval. Direct relations were not observed between consequences and the drinking beliefs regarding physical risk and health orientation. Finally, the present research found consistent support for the relation between mother–teen communications and drinking beliefs relevant to binge-drinking consequences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
The collapse of a suspended soffit consisting of portland cement plaster stucco on metal lath was investigated to determine the probable cause of collapse after over 30 years of service. Soffits of this type are often constructed with minimal, if any, details provided by the project architect or engineer. Without design guidance, the builder usually relies on typical industry practices and prior experience to construct these soffits. While experience may result in a safe installation in many instances, long-term performance without distress is no guarantee that no defects exist.  相似文献   
59.
The present study investigated the ability of a light and tone (LT) compound stimulus paired with cocaine infusions to reinstate cocaine-seeking behavior. Rats were trained to self-administer cocaine in the presence or absence of the LT during daily 3-hr sessions (maintenance). During Maintenance Days 5 and 10, rats underwent classical conditioning, whereby passive cocaine infusions were paired with either short-delayed, random, or no presentations of an LT. After extinction sessions, rats underwent test sessions in which the LT was presented in a noncontingent or response-contingent manner to measure conditioned cocaine-seeking behavior. The results demonstrated that response-contingent LT presentations significantly increased cocaine-seeking behavior and that the LT trained in a classical conditioning format transferred to an operant secondary reinforcer. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
60.
This article is a qualitative review of 32 publications appearing since J. Bossard and E. Boll's (1950) seminal work on family rituals was conducted. Definitions are offered whereby a distinction is made between family routines as observable practices and family rituals as symbolic representations of collective events. The relative occurrence of family routines, as described in the literature, appears to follow a developmental course and is affected by the cultural environment. Family routines and rituals were found to be related to parenting competence, child adjustment, and marital satisfaction. The studies were limited by inconsistent methods of assessing family routines, reliance on samples of convenience, and a failure to distinguish between direct and indirect effects. Recommendations are made to better integrate theory with empirical efforts to demonstrate the importance of family routines and rituals in contemporary life. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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