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11.
This study was designed to: (a) identify the perceptions of retirees about changes in their life patterns during retirement; (b) investigate the kinds of adjustment problems occurring in retirement as a basis for developing prevention oriented pre-retirement programs; and (c) identify extant factors which could demonstrate underlying themes relating to retirement adjustment. A 72-item, multiple response questionnaire was used to gather demographic data, information on use of time, pre-retirement planning, health problems, changing life patterns, and adjustment to retirement. It is the latter which is reported in these findings. The population included 1565 retirees from a designated company living in the south-eastern United States of America, with a response of 764 subjects (48.82%). Findings suggest the respondents were generally healthy and well adjusted; however, numerous adjustment problem areas were identified within the six life patterns. Additional factor analysis (principal components) demonstrated four factors of particular importance: satisfaction with retirement, retirement concerns, spousal relationships, and pre-retirement preparation outcomes.  相似文献   
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A panel of colorimetric assays was assessed for sensitivity, reproducibility, and performance in the investigation of the biocompatibility of a representative range of orthopædic biomaterials, using a commercially available human osteosarcoma-derived cell line. The MTT assay was the most sensitive, with a detection limit of 4×102 cells per well against background, while the NR assay was the least sensitive, with no colour change until the cell density reached 2×104 per well. All of the assays investigated showed a highly significant edge effect when within-plate reproducibility was examined; between-plate reproducibility was good for all assays except the MTT assay. When the assays were tested on cells adherent on biomaterials, there was a wide variation in the results obtained; in particular, the MTS assay showed poor reproducibility in the presence of materials. The MTT and BrdU assays both showed sufficient precision to detect cells on two of the materials studied. The study demonstrates that colorimetric assays are potentially useful in biocompatibility assessment but must be fully validated for the application chosen.  相似文献   
14.
The polymerase chain reaction was employed to correlate Salmonella serovars isolated from fecal material of greyhounds suffering from gastroenteritis with those isolated from the diet fed to the greyhounds prior to onset of diarrhea. Kennels around the Abilene, Kansas, area were contacted and supplied with materials needed to collect a portion of the diet each day. With the onset of diarrhea, the kennels were instructed to ship the fecal material and diet from the previous 10 days to the laboratory for testing. Forty-one fecal samples and corresponding diets were screened for Salmonella, Clostridium perfringens, Campylobacter jejuni, Staphylococcus aureus, Staphylococcus intermedius, and pathogenic (piliated) Escherichia coli by direct culture using standard procedures. The fecal material was also screened for coronavirus and parvovirus using electron microscopy. Thirty-five "normal" fecal samples were screened for all of the above mentioned microorganisms as a control. In addition, the fecal material was screened for E. coli verotoxins I and II and clostridial enterotoxins. A total of 61 Salmonella isolates were recovered from the 41 samples of feces and diet submitted for testing; 31 were recovered from the feces and 30 from the diet. Four Salmonella isolates were recovered from the normal fecal samples. Results obtained by PCR, plasmid profiles, antigenic analysis, and antibiogram profiles indicated that 16 of the 31 isolates recovered from the fecal material were the same strain as that recovered from the diet.  相似文献   
15.
Three experiments with 204 undergraduates examined the hypothesis that an audience can inhibit overt practice and thereby impair learning of unfamiliar words and enhance learning of familiar words. This hypothesis was derived from an analysis of motoric and symbolic mediation during learning. In comparison with learning while alone, the results show that the audience inhibited overt practice of unfamiliar and familiar words and that reduced practice was detrimental to learning unfamiliar words. Inhibition of overt practice with an audience enhanced learning of familiar words in only 1 of the experiments. Instructions to practice overtly reduced the audience-inhibition effect in learning unfamiliar words. The studies are discussed in the context of drive-theory explanations for social facilitation effects in learning. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A dynamical model for generating synthetic electrocardiogram signals   总被引:14,自引:0,他引:14  
A dynamical model based on three coupled ordinary differential equations is introduced which is capable of generating realistic synthetic electrocardiogram (ECG) signals. The operator can specify the mean and standard deviation of the heart rate, the morphology of the PQRST cycle, and the power spectrum of the RR tachogram. In particular, both respiratory sinus arrhythmia at the high frequencies (HFs) and Mayer waves at the low frequencies (LFs) together with the LF/HF ratio are incorporated in the model. Much of the beat-to-beat variation in morphology and timing of the human ECG, including QT dispersion and R-peak amplitude modulation are shown to result. This model may be employed to assess biomedical signal processing techniques which are used to compute clinical statistics from the ECG.  相似文献   
18.
There is an urgent demand for higher performance resists with superior resolution, sensitivity, and line edge roughness for both electron-beam and extreme ultraviolet lithography applications. Chemically amplified resists provide superior sensitivity compared to non-chemically amplified resists, but often suffer from resolution limitations and poor line edge roughness. A new class of negative tone chemically amplified molecular resists has been developed based on epoxide cross-linking that combines high sensitivity with low line edge roughness and excellent resolution. The most recent compound of this class (2-Ep) simultaneously demonstrates resolution of 25 nm half-pitch, sensitivity of 38 μC/cm2, and line edge roughness (3σ) of 2.9 nm under 100 keV e-beam exposure.  相似文献   
19.
提供了一种用于安德鲁反射测量样品制备新方法.该方法采用聚焦粒子束刻蚀和磁控溅射,可以获得可控的、干净的、无应力的纳米接触用于自旋极化探测.所制备的样品中,磁性和非磁性材料样品的反射谱都表现出复杂的峰和谷结构,这些结构可能源于与界面相关的零偏压反常以及与激发态相关的准离子相互作用.对另一个Co40Fe40B20合金样品采用简单的钕针尖压针方法进行了对比性测量,反射谱中没有观察到谷结构,但谱结构出现较明显的热扩展,这种热扩展可能来源于界面处的非弹性输运.所有的反射谱目前还不能由现有的理论给出令人满意的解释.利用点接触反射方法获得可靠的自旋极化信息还有赖于接触界面特征的进一步分析.而一个更切合实际的、更完善的理论成为迫切的需要.  相似文献   
20.
An essential component of today's embedded system is an instruction-set processor running real-time software. All variations of these core components contain at least the minimum data-flow processing capabilities, while a certain class contain specialized units for highly data-intensive operations for Digital Signal Processing (DSP). For the required level of memory interaction, the parallel executing Address Calculation Unit (ACU) is often used to tune the architecture to the memory access characteristics of the application. The design of the ACU is performance critical. In today's typical design flow, this design task is somewhat driven by intuition as the transformation from application algorithm to architecture is complex and the exploration space is immense. Automatic utilities to aid the designer are essential; however, the key compilation techniques which map high-level language constructs onto addressing units have lagged far behind the emergence of these units. This paper presents a new retargetable approach and prototype tool for the analysis of array references and traversals for efficient use of ACUs. In addition to being an enhancement to existing compiler systems, the ArrSyn utility may be used as an aid to architecture exploration. A simple specification of the addressing resources and basic operations drives the available transformations and allows the designer to quickly evaluate the effects on speed and code size of his/her algorithm. Thus, the designer can tune the design of the ACU toward the application constraints. ArrSyn has been successfully used together with a C compiler developed for a VLIW architecture for an MPEG audio decoding application. The combination of these methods with the C compiler showed on average a 39% speedup and 29% code size reduction for a representative set of DSP benchmarks.  相似文献   
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