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181.
Participatory modelling has provided a new approach to overcome the problem of data scarcity which formerly interfered with the environmental planning for the restoration of the Kolleru-Upputeru wetland ecosystem on the east coast of Andhra Pradesh in South India. New ways had to be found to address the shortcomings of traditionally validated simulation models. The traditional validation process was replaced by joint plausibility discussions and shared vision building in order to improve the understanding of cause-effect relationships and proposals for restoration measures. This study has aimed to match the tacit knowledge of the local stakeholders with explicit scientific knowledge in order to create (i) a mutual basis for an integrated approach as opposed to single-issue measures and (ii) a mutual agreement on follow-up steps needed to sustain both the livelihood of the people as well as the wetland ecosystem. The challenge was to address the hydrological and social complexity. On the basis of a literature review, input data for model simulations were generated from the location-specific knowledge of stakeholders and a rapid field appraisal. The model simulations were used to predict the effects of a number of restoration options. In two workshops, these restoration options were discussed with the stakeholders in order to improve the mutual understanding of the complexity of the wetland system and to reach an agreement on the outlines of an integrated action plan. The participatory modelling approach proved to be a useful tool to obtain a consensus of opinions among the stakeholders.  相似文献   
182.
Summary Transformations of attributed program trees form an essential part of compiler optimizations. A strategy of repeatedly applying alternate attribute evaluation and tree transformation phases is discussed. An attribute evaluation phase consists of a sequence of passes over the tree. A tree transformation phase consists of a single pass, which is never interrupted to carry out a re-evaluation. Both phases can be performed in parallel. This strategy requires a distinction between consistent (i.e., correct) and approximate attribute values. Tree transformations can be considered safe if they guarantee that the attribute values everywhere in the program tree will remain consistent or will become at least approximations of the consistent values, so that subsequent transformations can be applied correctly.This attribute evaluation and tree transformation strategy shows similarities with the evaluation methods for circular attribute grammars.  相似文献   
183.
Since the paper by Hammons e.a. [1], various authors have shown an enormous interest in linear codes over the ring ℤ4. A special weight function on ℤ4 was introduced and by means of the so called Gray map ϕ : ℤ4→ℤ2 2 a relation was established between linear codes over ℤ4 and certain interesting non-linear binary codes of even length. Here, we shall generalize these notions to codes over ℤ p2 where p is an arbitrary prime. To this end, a new weight function will be proposed for ℤ p2 . Further, properties of linear codes over ℤ p2 will be discussed and the mapping ϕ will be generalized to an isometry between ℤ p2 and ℤ p p , resp. between ℤ p2 n and ℤ p pn . Some properties of Galois rings over ℤ q will be described and two dual families of linear codes of length n = p m − 1, gcd(m, p) = 1, over ℤ q will be constructed. Taking q = p 2, their images under the new mapping can be viewed as a generalization of the binary Kerdock and the Preparata code, although they miss some of their nice combinatorial properties. Received: June 19, 2000; revised version: November 6, 2000  相似文献   
184.
Long-term exercise induces physiological cardiac adaptation, a condition referred to as athlete’s heart. Exercise tolerance is known to be associated with decreased cardiac passive stiffness. Passive stiffness of the heart muscle is determined by the giant elastic protein titin. The adult cardiac muscle contains two titin isoforms: the more compliant N2BA and the stiffer N2B. Titin-based passive stiffness may be controlled by altering the expression of the different isoforms or via post-translational modifications such as phosphorylation. Currently, there is very limited knowledge about titin’s role in cardiac adaptation during long-term exercise. Our aim was to determine the N2BA/N2B ratio and post-translational phosphorylation of titin in the left ventricle and to correlate the changes with the structure and transverse stiffness of cardiac sarcomeres in a rat model of an athlete’s heart. The athlete’s heart was induced by a 12-week-long swim-based training. In the exercised myocardium the N2BA/N2B ratio was significantly increased, Ser11878 of the PEVK domain was hypophosphorlyated, and the sarcomeric transverse elastic modulus was reduced. Thus, the reduced passive stiffness in the athlete’s heart is likely caused by a shift towards the expression of the longer cardiac titin isoform and a phosphorylation-induced softening of the PEVK domain which is manifested in a mechanical rearrangement locally, within the cardiac sarcomere.  相似文献   
185.
Full‐fat soya beans were separated into hulls and cotyledons. After separation the cell wall fraction was extracted from the cotyledons. These purified cell walls were sequentially extracted with 0.05 M cyclohexane‐trans‐1,2‐diamine‐N,N,N ′,N ′‐tetraacetate (CDTA) + 0.05 M NH4 oxalate (extract 1), 0.05 M NaOH (extract 2), 1 M KOH (extract 3) and 4 M KOH (extract 4) to fractionate the cell wall into its polysaccharide fractions. The extraction procedure was designed to first extract the pectic fraction (extracts 1 and 2), after which more hemicellulose was extracted in subsequent steps (extracts 3 and 4). In addition to the polysaccharides solubilised during extraction, the residues after each extraction step were collected. Extracts and residues were analysed for their fermentation characteristics using an in vitro gas production procedure. Fermentability of the sequential extracts increased for each subsequent extraction step, as witnessed by an increasing rate of fermentation (from 2.2 to 10.0% h−1) and decreasing half‐time of gas production (from 56.0 to 18.7 h). Fermentability of the residues increased after pectins had been removed in the first two extraction steps, as witnessed by a shorter half‐time of gas production (from 47.0 to 29.7 h). Fermentability was similar for residues 2 and 3, but decreased again for residue 4, which was deemed to consist mainly of cellulose. The different cell wall sugars were degraded at different rates, with a rapid rate of degradation for galactose and arabinose, an intermediate rate for xylose and uronic acids and a slow rate for glucose. The sugar degradation rates for extract 1 had a similar ranking. These results are discussed in light of the concept that pectins determine the pore size of the cell wall matrix (Carpita NC and Gibeant DM, Planta J 3 : 1–30 (1993) and the model of the cell wall architecture of legumes of Hatfield (Hatfield RD, in Forage Cell Wall Structure and Digestibility, Ed by Jung HG, Buxton DR, Hatfield RD and Ralph J. American Society of Agronomy/Crop Science Society of America/Soil Science Society of America, Madison, WI, pp 285–313 (1993)). © 2000 Society of Chemical Industry  相似文献   
186.
Nemaline myopathy (NM) is characterized by skeletal muscle weakness and atrophy. No curative treatments exist for this debilitating disease. NM is caused by mutations in proteins involved in thin-filament function, turnover, and maintenance. Mutations in nebulin, encoded by NEB, are the most common cause. Skeletal muscle atrophy is tightly linked to upregulation of MuRF1, an E3 ligase, that targets proteins for proteasome degradation. Here, we report a large increase in MuRF1 protein levels in both patients with nebulin-based NM, also named NEM2, and in mouse models of the disease. We hypothesized that knocking out MuRF1 in animal models of NM with muscle atrophy would ameliorate the muscle deficits. To test this, we crossed MuRF1 KO mice with two NEM2 mouse models, one with the typical form and the other with the severe form. The crosses were viable, and muscles were studied in mice at 3 months of life. Ultrastructural examination of gastrocnemius muscle lacking MuRF1 and with severe NM revealed a small increase in vacuoles, but no significant change in the myofibrillar fractional area. MuRF1 deficiency led to increased weights of various muscle types in the NM models. However, this increase in muscle size was not associated with increased in vivo or in vitro force production. We conclude that knocking out MuRF1 in NEM2 mice increases muscle size, but does not improve muscle function.  相似文献   
187.
Herein, a simple, solvent-free method to fabricate polymer-encapsulated halide perovskite photoconductors is described. Dry mechanochemical synthesis is used to prepare CsPbBr3 in the presence of poly(butyl methacrylate) (PBMA). The resulting composite powder is then heated and pressed into a free-standing disk with a thickness controlled by a metallic spacer ring. The disk can be laminated on a glass substrate patterned with interdigitated electrodes, resulting in a planar photoconductor device. The best photoconductive performance is obtained for disks that consist of 75 wt.% CsPbBr3 in PBMA, reaching a detectivity of ≈2 × 1011 Jones. Moreover, by adjusting the thickness of the disk, narrowband detectors can be obtained due to charge collection narrowing. Depending on the thickness of the pressed disk, the position and width of the detectivity peak can be tuned. At last, the disks are tested as possible absorber materials for X-ray detectors, where ow detection limit, and fast and linear response are measured for perovskite-polymer disks with 50 wt.% perovskite content. This work shows a simple and versatile approach toward the fabrication of halide perovskite photodetectors, which can be carried out in air and without the use of solvents.  相似文献   
188.
Establishing the rapid and accurate diagnosis of sepsis is a key component to the improvement of clinical outcomes. The ability of analytical platforms to rapidly detect pathogen-associated molecular patterns (PAMP) in blood could provide a powerful host-independent biomarker of sepsis. A novel concept was investigated based on the idea that a pre-bound and fluorescent ligand could be released from lectins in contact with high-affinity ligands (such as PAMPs). To create fluorescent ligands with precise avidity, the kinetically followed TEMPO oxidation of yeast mannan and carbodiimide coupling were used. The chemical modifications led to decreases in avidity between mannan and human collectins, such as the mannan-binding lectin (MBL) and human surfactant protein D (SP-D), but not in porcine SP-D. Despite this effect, these fluorescent derivatives were captured by human lectins using highly concentrated solutions. The resulting fluorescent beads were exposed to different solutions, and the results showed that displacements occur in contact with higher affinity ligands, proving that two-stage competition processes can occur in collectin carbohydrate recognition mechanisms. Moreover, the fluorescence loss depends on the discrepancy between the respective avidities of the recognized ligand and the fluorescent mannan. Chemically modulated fluorescent ligands associated with a diversity of collectins may lead to the creation of diagnostic tools suitable for multiplex array assays and the identification of high-avidity ligands.  相似文献   
189.
The aim of the present field study is to expand the understanding of how characteristics of recruiters relate to their adoption of new selection technology. In two studies, among 198 recruiters, we used the Technology Acceptance Model (TAM), together with two measures of personality (i.e., openness to experience and neuroticism), two information technology specific individual differences (i.e., personal innovativeness in information technology and computer self-efficacy), and reactions to and actual usage of new technology. Both studies showed that all recruiter characteristics (except openness to experience) relate to perceptions of usefulness and ease of use, and that these perceptions relate to intentions to use new selection technologies. Study 2 showed that recruiter characteristics predict perceptions of usefulness and ease of use over and above established predictors of the TAM. Perceptions of usefulness and ease of use were better predictors of intentions to use new technology than perceptions of face validity, predictive validity, and fairness. Thus, when it comes to the adoption of new selection technology, recruiter characteristics, and perceptions of usefulness and ease of use play an important role.  相似文献   
190.
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