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91.
Rancidity development during frozen storage (?20 °C) of an underutilised medium‐fat‐content fish species, horse mackerel (Trachurus trachurus), was studied. Special attention was given to the effect of previous chilled storage (0, 1, 3 and 5 days) on the quality of the frozen fish. For this, chemical (free fatty acid and conjugated diene contents; peroxide value, PV; thiobarbituric acid index, TBA‐i; fluorescent compound formation) and sensory (rancid odour and taste) analyses were carried out. Hydrolytic rancidity showed an increase with frozen storage time; however, no effect of previous chilling time was observed on the frozen product. Oxidative rancidity measured by chemical (PV, TBA‐i and fluorescence) and sensory (odour and taste) indices increased with frozen storage time and also with previous chilling time. Satisfactory quality was maintained up to 7 months of frozen storage of horse mackerel provided that a short chilling time (not longer than 3 days) was employed. © 2002 Society of Chemical Industry  相似文献   
92.
The overall goal of this study was to evaluate the environmental performance of the process currently used to package and palletize ceramic floor and wall tiles, and to propose and analyse improvements from an environmental point of view. After developing a life cycle inventory of the primary and tertiary packaging, the life cycle assessment was applied according to mandatory and optional elements of ISO 14042. The results are presented in three parts: the first quantifies the environmental behaviour of the current packaging system, the second examines strategies focused on minimizing the environmental burdens of such critical elements, and the third quantifies the environmental improvements, compared with the initial situation, that are obtained with the application of each improvement. The simultaneous incorporation of all the proposed improvements into the packaging system can reduce impact within the 18–45% range, depending on the impact method that is applied. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
93.
The layer-by-layer deposition of thin films of CdTe nanoparticles and three different polyelectrolytes has been investigated. Photoluminescence spectra were used to monitor the energy transfer properties within the films. As the number of bilayers in a thin film was increased a decrease in the energy of the light emitted was observed. The wavelength change is a two-stage process. Deposition of the first one to two bi-layers of a thin film produced a sharp energy change (626 nm to 637 nm with the addition of a single bi-layer) whereas deposition of subsequent bi-layers produced a more gradual energy change (642 nm-646 nm with the addition of 5 bi-layers). A space-filling mechanism is suggested to account for these changes; smaller nanoparticles penetrate the earlier levels of a thin film and increase the inter-particle energy transfer opportunities within the layers.  相似文献   
94.
Four strains of Aujeszky's Disease virus (ADV) were included in this study; three Mexican field isolates (215,145 and C-8) in conjunction with the Shope reference strain of ADV, which has known pathogenic characteristics. All four strains were included in each treatment, which consisted of heat treatment, trypsin treatment and passed ten times on chicken embryo fibroblasts. Both virus titer and plaque size were determined on the first and tenth passage and on treated and untreated strains. On each of the treatments, the plaque size had significant differences (p = 0.001) which had relation to the two factors studied, namely strain and passage level. There was no significant variation related to the type of treatment between strains. With the strains under study, the authors also made rabbit pathogenicity tests, and it was found that on passage one, the strains caused clear nervous symptoms and death, while on the tenth passage level, the Mexican strains produced slight pruritus, few nervous symptoms and allowed the rabbits to survive. The mouse test revealed an increased median death time after the treatments, as well as a large increase in standard deviations. These data are interpreted as an increased heterogeneity of the strains in all of the treatments to the strains of viruses.  相似文献   
95.
Tardive dyskinesia (TD) is the most feared and troublesome extrapyramidal side-effect of prolonged neuroleptic (NL) treatment. We present a review of TD. Its pathophysiology remains elusive, although extrapyramidal symptoms (EPS) increase the liability for TD. Nowadays, therefore, avoidance of all EPS remains the best preventive strategy, as it is not possible to predict which liable patients will develop TD, or of what type or severity. TD frequently includes dystonic features, and is more disabling when these dystonias are present. Clozapine (CLZ) has been reported to be effective in suppressing nearly 60% of TD syndromes, specially those with dystonic features. Based on the few reports in the literature on CLZ and TD by the early 1980s, we started to videotape the first severe TD patient treated with CLZ in 1984. We present the first three case reports of severe TD, with prominent disabling dystonic features, treated with CLZ and videotaped since pretreatment and then periodically for 12, 8 and 5 years of follow-up, respectively. The patients' current diagnosis, gender and age are: Case 1, DSM-IV Schizophrenia Residual Type, male, 39 years; Case 2, DSM-IV Polysubstance Related Disorder, Borderline Personality Disorder, female, 28 years; Case 3, DSM-IV Schizoaffective Disorder, male, 40 years. Two of them presented with a recurrence of TD because of CLZ interruption within the first 2 months of treatment, with no further breakthrough to date. The first two cases have complete remission of TD; the third case is still improving after 5 years of CLZ treatment, with only minor dystonic features persisting that constitute no impairment for work or daily routines at present. All patients, independent of their psychiatric primary diagnosis, have shown significant and progressive improvement in both motor and psychosocial aspects. None of them has been rehospitalized. Long-term treatment and follow-up is required to avoid TD recurrence and to assure full assessment of treatment effectiveness. Ideally, periodic video recording with standardized examination is advisable for long-term follow-up and outcome assessment. At present, CLZ could be regarded as the drug of choice for patients with TD, specially for those with disabling and or dystonic features and who require ongoing NL therapy. The use of novel antipsychotic agents for TD treatment and prevention, with their low EPS liability, is promising, but has yet to be tested.  相似文献   
96.
The way in which a cascade mechanism from the C3Pi(u) state affects the population of the v = 0 level of the B3Pi(g) state in a N2 laser is studied. The spectra of the 0-1 IR laser band are fit by using simple theoretical calculations that account for the population of the three laser levels involved, C3Pi(u) B3Pi(g) and A3Sigma(u)+ and two excitation mechanisms, direct electron impact and cascade. The inhibition of the 0-0 UV laser band showed a strong influence on the 0-1 IR laser band output.  相似文献   
97.
The data link layer protocol for the integrated services digital network (ISDN) user/network interface, known as link access protocol-D (LAPD), is a protocol that operates at layer 2 of the open systems interconnection (OSI) architecture. Its purpose is to safely convey information between layer 3 entities using the D-channel. The information types that LAPD is intended to transport include call control signaling, packet mode communications, and management information. Observations are made in this article about what are, in the authors' opinion, the most confusing points of CCITT Recommendation Q.921 with comments related to data link layer address field, broadcast connections, terminal endpoint identifier (TEI) management procedures, layer 2 frames exchange, and connection management entity response to MDL-error indication primitives. This article intends solely to clarify the recommendations so that their concepts and procedures become easier to understand and implement, which can lead to significant saving of time for those who must eventually use LAPD procedures or develop the software for handling them  相似文献   
98.
The objective of this work is to identify the causes that led to a failure of the crane hook in service. The study of the accident includes: (1) a summary and analysis of the peculiarities inherent to the standards that determine the manufacture and use of this type of device, (2) metallographic, chemical and fractographic analyses, (3) assessment of the steel mechanical behaviour in terms of Vickers hardness profile, its tensile strength and fracture energy, and (4) simulation of the thermal history of the hook. The visual and microstructural inspections reveal some evidences that a weld bed was deposited on the hook surface. Several cracks grew from that area into the material. Fracture surface shows features typical of brittle failures (transgranular cleavage fracture). The unalloyed, low-carbon steel contains a relatively low aluminium (<0.025%) and high non-combined nitrogen (>0.0075%) content. All the gathered evidences are in agreement with a strain-aging process triggering the embrittlement of the material, with the fracture starting from a crack generated at the heat affected zone of an uncontrolled welding of the hook.  相似文献   
99.
Software model checking consists in applying the most powerful results in formal verification research to programming languages such as C. One general technique to implement this approach is producing a reduced model of the software in order to employ existing and efficient tools, such as SPIN . This paper focusses on the application of this approach to the avionics software constructed on top of the Application Executive Software (APEX ) Interface, which is widely employed by manufacturers in the avionics industry. It presents a method to automatically extract PROMELA models from the C source code. In order to close the extracted model during verification, we built a reusable APEX ‐specific environment. This APEX environment models the execution engine (i.e. an APEX compliant real‐time operating system) that implements APEX services. In particular, it explains how to deal with aspects such as real‐time and APEX scheduling. Time is modelled in such a way that the we save time and memory by avoiding the analysis of irrelevant steps. This model of time and the construction of a deterministic scheduler guarantees the scalability of our approach. The paper also presents a tool that can verify realistic applications, and that has been used as a novel testing method to ensure the correctness of our APEX environment. This testing method uses SPIN to execute official APEX test cases. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
100.
BACKGROUND/AIMS/METHODS: The distribution characteristics of a human colon carcinoma cell line, KM12-HX cells, were examined. After intraportal vein (i.p.v.) or intravenous (i.v.) injection into rats, almost all the injected tumor cells are distributed to liver or lung, respectively, both after 30 s and 30 min. Our previous kinetic analysis of the fate of tumor cells revealed that the cumulative amount of tumor cells distributed in the liver is a factor determining the degree of metastasis. Thus, we examined the mechanism of initial efficient trapping of tumor cells by the liver in more detail. RESULTS: Thirty minutes after tumor cells were injected into the left ventricle of the heart, the distribution of tumor cells was more restricted in several tissues (kidney, small intestine, large intestine and spleen), as compared with the distribution of microspheres undergoing 100% extraction, indicating that the first-pass extraction of KM12-HX cells is incomplete in these organs. The hepatic first-pass distribution of these tumor cells was unaffected by pretreatment of liposomes, such that the preinjected amount was sufficient to saturate the phagocytotic function of macrophages. Thus, the mechanism of initial distribution of the tumor cells to the liver is different from the mechanism of liposome uptake by macrophages. Considering that the diameter of microvessels in sinusoid and KM12-HX cells is approximately 7 and 12 microm, respectively, it is possible that these tumor cells are trapped physically in hepatic microvessels. In fact, after i.p.v. injection of microspheres 5 microm in diameter, only 20% of the dose was distributed to liver and the rest to other tissues. In contrast, almost 100% of microspheres 10 microm in diameter were distributed to the liver. CONCLUSIONS: These results support the hypothesis that the initial organ distribution of blood-borne tumor cells is determined by mechanical and physical properties of the cells.  相似文献   
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