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111.
AIM: Patients with various disorders of gastric function were studied with radiolabeled test meals of different consistency to elaborate the effect of ingested media on gastric peristalsis and emptying. METHODS: In 12 patients parameters of gastric function were intraindividually compared after ingestion of a semiliquid and a solid test meal. In addition to the standard evaluation derived from time activity curves condensed images were established from two fixed time intervals (early and late period). These images were used to evaluate the amplitude and frequency of gastric contractions using Fourier analysis. RESULTS: As expected gastric emptying was influenced by the consistency of the test meal. Mean emptying rates for the solid meal were significant lower than those for the semiliquid one (p < 0.01). The amplitude and frequency of gastric contractions, however, did not depend on the consistency of the test meal. Within the course of the examination contraction amplitudes significantly increased (p < 0.05) from the early to the late period using both, solid as well as semiliquid test meals. The frequency of gastric contractions remained unchanged. CONCLUSION: As shown by an intraindividual data comparison amplitude and frequency of gastric contractions seem to be independent of the consistency of ingested test meals whereas gastric emptying is significantly influenced by the administered media. Semiliquid meals offer advantages with respect to the shorter examination time and simpler preparation and therefore may be preferred for routine use. Since amplitudes seem to vary within the observation period standardized acquisition protocols are recommended for the evaluation of this parameter.  相似文献   
112.
113.
The purpose of this article is to present a treatment of unbounded dependencies which is currently being experimented with in Eurotra. The treatment is based on the coindexation tool designed by the authors as an extension to the E-Framework, Eurotra's NLP formalism. At present, the tool has been tested in a systematic way in the Danish, French, Italian, and Spanish modules of the Eurotra translation system. Testing work on other languages (especially German) is in progress. Our article is organized as follows: in section 1, we discuss the linguistic and translational motivations for the treatment presented here; in section 2, we give the syntax and semantics of the two main components of the coindexation tool, namely the recursion markers and the copy operator; section 3 shows how this machinery can be applied for the implementation of unbounded dependency constructions according to our approach.
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114.
The authors addressed 5 issues bearing on the validity of the construct of depressive personality disorder (DPD): its relationship with the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) mood and personality disorders and normal personality dimensions of negative and positive affectivity, its stability over 30-months, and its impact on the course of Axis I depressive disorders. Two samples were used: 156 outpatients with mood disorders, personality disorders, or both, and 267 of their 1st-degree relatives. The association between DPD and dysthymia was fairly modest, whereas the associations with major depression and the personality disorders were quite low. DPD was moderately correlated with both negative and positive affectivity; however, it contributed unique information beyond that available from the 2 emotional superfactors. Finally, DPD was moderately stable over a 30-month period and was associated with a poorer course of depression.  相似文献   
115.
Very High-Speed True Random Noise Generator   总被引:1,自引:0,他引:1  
In this work an original CMOS implementation of a discrete-time deterministic-chaos algorithm for random bit generation is presented. The proposed circuit topology prevents the degradation of the generated-sequence statistical properties that can be caused by several factors, including the parameter spreading of the technological processes. Experimental results show that, with a final rate of 3 Mbit/s, the circuit is compliant with the most recent security requirements for cryptographic modules issued by the American National Institute of Standards and Technologies.  相似文献   
116.
The literature was reviewed to quantify the risk of complications related to the relief of obstruction in urinary retention. We also sought to determine whether the risk of complications is higher with rapid or gradual decompression (or "clamping") of the obstructed urinary bladder. The medical literature was identified by a search of the MEDLINE database and a manual review of the bibliographies of the identified articles. Studies show that, after quick, complete relief of obstruction, hematuria occurs in 2 to 16% of patients; however, clinically significant hematuria is rare. After relief of obstruction, blood pressure often decreases, but it usually normalizes and does not progress to clinically significant hypotension. Postobstructive diuresis occurs after relief of obstruction in 0.5 to 52% of patients; however, it is easily managed and rarely of clinical significance. We were unable to identify any randomized controlled studies that directly compared quick, complete emptying with gradual emptying of the obstructed bladder. Moreover, we identified no studies supporting the practice of gradual emptying of the obstructed bladder. The available published studies support quick, complete emptying for relief of the obstructed urinary bladder. We conclude that hematuria, hypotension, and postobstructive diuresis may occur after decompression of the obstructed urinary bladder, but these complications are rarely clinically significant. Quick, complete emptying of the obstructed bladder is safe, simple, and effective and is recommended as the optimal method for decompressing the obstructed urinary bladder. Prudent, supportive care is needed for all patients, with special attention to elderly patients and those with hypovolemia.  相似文献   
117.
Image‐ and data‐parallel rendering across multiple nodes on high‐performance computing systems is widely used in visualization to provide higher frame rates, support large data sets, and render data in situ. Specifically for in situ visualization, reducing bottlenecks incurred by the visualization and compositing is of key concern to reduce the overall simulation runtime. Moreover, prior algorithms have been designed to support either image‐ or data‐parallel rendering and impose restrictions on the data distribution, requiring different implementations for each configuration. In this paper, we introduce the Distributed FrameBuffer, an asynchronous image‐processing framework for multi‐node rendering. We demonstrate that our approach achieves performance superior to the state of the art for common use cases, while providing the flexibility to support a wide range of parallel rendering algorithms and data distributions. By building on this framework, we extend the open‐source ray tracing library OSPRay with a data‐distributed API, enabling its use in data‐distributed and in situ visualization applications.  相似文献   
118.
Metal halide perovskites are maturing as materials for efficient, yet low cost solar cells and light‐emitting diodes, with improving operational stability and reliability. To date however, most perovskite‐based devices contain Pb, which poses environmental concerns due to its toxicity; lead‐free alternatives are of importance to facilitate the development of perovskite‐based devices. Here, the germanium‐based Ruddledsen–Popper series (CH3(CH2)3NH3)2(CH3NH3)n?1GenBr3n+1 is investigated, derived from the parent 3D (n = ∞) CH3NH3GeBr3 perovskite. Divalent germanium is a promising, nontoxic alternative to Pb2+ and the layered, 2D structure appears promising to bolster light emission, long‐term durability, and moisture tolerance. The work, which combines experiments and first principle calculations, highlights that in germanium bromide perovskites the optical bandgap is weakly affected by 2D confinement and the highly stereochemically active 4s2 lone pair preludes to possible ferroelectricity, a topic still debated in Pb‐containing compounds.  相似文献   
119.
We present an algorithm to compute an approximation of the generalized Voronoi diagram (GVD) on arbitrary collections of 2D or 3D geometric objects. In particular, we focus on datasets with closely spaced objects; GVD approximation is expensive and sometimes intractable on these datasets using previous algorithms. With our approach, the GVD can be computed using commodity hardware even on datasets with many, extremely tightly packed objects. Our approach is to subdivide the space with an octree that is represented with an adjacency structure. We then use a novel adaptive distance transform to compute the distance function on octree vertices. The computed distance field is sampled more densely in areas of close object spacing, enabling robust and parallelizable GVD surface generation. We demonstrate our method on a variety of data and show example applications of the GVD in 2D and 3D.  相似文献   
120.
The glutamate dehydrogenase gene from the hyperthermophilicarchaeon Pyrococcus furiosus has been functionally expressedin Escherichia coli under the control of the X, PL promoter.The P.furiosus glutamate dehydrogenase amounted to 20% of thetotal E.coli cell protein, and the vast majority consisted ofhexamers. Following activation by heat treatment, an enzymecould be purified from E.coli that was indistinguishable fromthe glutamate dehydrogenase purified from P.furiosus. Hybridgenes, that consisted of the coding regions for the homologousglutamate dehydrogenases from P.furiosus and the mesophilicbacterium Clostridium difficile, were constructed and successfullyexpressed in E.coli. One of the resulting hybrid proteins, containingthe glutamate binding domain of the C.difficile enzyme and thecofactor binding domain of the P.furiosus enzyme, did not showa detectable activity. In contrast, the complementary hybridcontaining the P.furiosus glutamate and the C.difficile cofactorbinding domain was a catalytically active hexamer that showeda reduced substrate affinity but maintained efficient cofactorbinding with the specificity found in the Clostridium symbiosumenzyme. Compared with the C.difficile glutamate dehydrogenase,the archaeal-bacterial hybrid is slightly more thermoactive,less thermostable but much more stable towards guanidinium chloride-inducedinactivation and denaturation  相似文献   
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