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81.
A case undergoing conduit procedure for tetralogy of Fallot with pulmonary atresia was complicated postoperatively by bacteremia due to non-fermentative Gram-negative rods and by disseminated intravascular coagulation. He was able to be cured without any sequela. The patient was a 16-year-old male, who had undergone Blalock-Taussig anastomosis in his infancy. The present operation was carried out as follows: ventricular septal defect was closed with a Teflon-patch and discontinuity between the right ventricle and the pulmonary artery was corrected using a Hancock's valved conduit. Two weeks after the operation, pleural effusion in the right chest cavity was shown by a chest X-ray film. On the 32nd postoperative day, high fever with chills occurred, and subsequently developed pulmonary edema, shock and hemorrhagic tendencies with petechia. Pseudomonas aeruginosa, Flavobacterium and Alcaligenes faecalis were detected by the culture of pleural effusion. The platelet count decreased to about 10,000/microliters. Carbenicillin, tobramycin and minocycline were administered for the infection, and heparin and aprotinin were used for disseminated intravascular coagulation. By these treatments for about 6 months, the patient became well and was discharged without any sequela.  相似文献   
82.
A spectrum of oxidative lesions was observed in a bacteriophage-based model system that is very sensitive to the photodynamic activity of selected dyes. When suspensions of the intact bacteriophage Q beta were exposed to methylene blue plus light (MB + L), inactivating events, or "hits" occurred that were oxygen-dependent and that were associated with the formation of several specific lesions: (1) carbonyl moieties on proteins, (2) 8-oxo-7,8-dihydroguanine (8-oxoGua), and (3) single-strand breaks (ssb) in the RNA genome and (4) RNA-protein crosslinks. Formation of carbonyl groups associated with protein in the Q beta phage preparation correlated positively with photoinactivation of the phage with increasing doses of either of the sensitizers MB or rose bengal. Strand breaks in the Q beta genomic RNA were observable at high MB concentrations but appeared not to be significant at the lower concentrations of MB, as full-length Q beta RNA was observable well beyond the 99% inactivation point in MB dosage. It was shown that the number of 8-oxoGua lesions were unlikely to be sufficient to account for the number of lethal events. Following exposure to MB + L, crosslink formation between Q beta RNA and protein was observed by virtue of the location of RNA at the interface of phenol-aqueous extractions of phage suspensions. A significant increase over background of RNA-protein complexes (including full-length Q beta RNA) was observed at the lowest concentration of MB tested (0.5 microM), which corresponded roughly to an average of 2 lethal hits per phage or approximately 13% survival compared to the zero MB control (100% survival). Due to its close correlation with Q beta inactivation and its expected lethality, RNA-protein crosslink formation may be important as an inactivating lesion in bacteriophage Q beta following MB + L exposure.  相似文献   
83.
Six core-penetrating Rydberg series have been assigned in the CaCl molecule by a combination of double-resonance spectroscopic techniques. Two 2Sigma+ series, with approximate quantum defects (delta) of 0.51 and 0.25, have been observed with effective principal quantum numbers (n*) in the range of 5-8 using the D2Sigma+ state as the resonant intermediate state for REMPI and/or ion-dip detection. A third 2Sigma+ series with delta approximately 0.84 and a 2Delta series with delta approximately 0.95 have been observed with n* = 16-18 using the A2Pi3/2 state as the resonant intermediate state for preparation of v+ = 1 vibrationally autoionizing states. Two additional series in the same region with delta approximately 0.90 and 0.07 are tentatively identified as the expected core-penetrating 2Pi series. Vibrational assignments have been confirmed in many cases on the basis of isotope shifts between the 35Cl and 37Cl isotopomers. The ion-dip and REMPI spectra display linewidths systematically broadened by predissociation. In addition to the assigned core-penetrating series, both the REMPI and the ion-dip spectra display some sharper features that have not yet been assigned. These sharper features most likely arise from perturbations of optically "bright" core-penetrating states by nominally "dark" higher-l core-nonpenetrating states. Copyright 1999 Academic Press.  相似文献   
84.
A patient with chronic idiopathic mediastinal fibrosis (MF) without concomitant retroperitoneal fibrosis is reported. He presented with pleuritis, malaise and pain and stiffness in the thoracic spine. During the 3.5 years of observation no clinical signs of obstruction of adjacent visceral structures in the chest cavity have developed. The diagnosis was made by CT, X-rays of the chest remained normal throughout the observation period, except for thickening of the involved pleura. The administration of high doses of oral corticosteroids did not appear to influence either clinical symptoms or the manifestations of MF as seen by CT.  相似文献   
85.
To investigate the effects of loading rate and plate thickness on the fracture toughness of PMMA (polymethyl methacrylate) under impact loading, two methods, A method and B method, are applied as follows. In the A method, a dynamic finite element method and a strain gage method are applied to measure the dynamic fracture toughness in the fracture test using an air gun. In the B method, a single axis strain gage method is applied to measure the critical dynamic stress intensity factor, namely dynamic fracture toughness, in the fracture test using a weight dropping type apparatus. The dimensions of the PMMA specimen are L = 140 mm length and W = 30 mm width. Three values of the plate thickness B, 15.0 mm, 10.0 mm and 5.0 mm, are selected to investigate the plate thickness effect in the fracture test. Both results by the A and B methods precisely indicated the minimum value and the loading rate effect on the dynamic fracture toughness.  相似文献   
86.
Malignant histiocytosis (MH)-like B-cell lymphoma (BCL) is a neoplastic proliferation of large B cells clinically characterized by fever, hepatosplenomegaly, haemophagocytosis and abnormal laboratory data, without lymphadenopathy or skin lesions. Interestingly, most cases have been reported in Asian patients, and it is unclear whether MH-like BCL is biologically distinct from conventional large B-cell lymphomas. We report five Japanese patients with MH-like BCL. Biopsied specimens of bone marrow, liver and/or spleen showed infiltration of neoplastic B cells accompanied by haemophagocytosing histiocytes. Lymphoma cells were positive for CD19, CD20 and HLA-DR surface antigens, and negative for CD5 and CD10. In four cases elevated serum levels of interleukin (IL)-6 and the soluble IL-2 receptor isoform were noted, but not IL-1beta, IL-2 or tumour necrosis factor-alpha. Autopsies of two cases were pathologically diagnosed as intravascular lymphomatosis (IVL). Based on these observations, the current and nine previous cases reported as MH-like BCL in Japan were re-evaluated. They appear to form a peculiar variant of IVL, characterized by bone marrow involvement at presentation, haemophagocytic syndrome, and a rapidly aggressive clinical course, but rarely neurological complications or skin lesions. This variant may merit separate consideration because of the problems posed in the initial diagnosis and therapeutic approaches.  相似文献   
87.
The Inter-university Upper atmosphere Global Observation NETwork (IUGONET) project focuses on handling ground-based observational data of the upper atmosphere. To this end, the project members have been developing a data analysis software package which is based on Interactive Data Language (IDL). Filling the spatial gaps in observational data requires the use of numerical models. In this paper, we discuss an IDL software package for global ionospheric conductivity by integration of 3rd party numerical models. The model can be used to create further derived models.  相似文献   
88.
Avoiding premature convergence to local optima and rapid convergence towards global optima has been the major concern with evolutionary systems research. In order to avoid premature convergence, sufficient amount of genetic diversity within the evolving population is considered necessary. Several studies have focused to devise techniques to control and preserve population diversity throughout the evolution. Since mutation is the major operator in many evolutionary systems, such as evolutionary programming and evolutionary strategies, a significant amount of research has also been done for the elegant control and adaptation of the mutation step size that is proper for traversing across the locally optimum points and reach for the global optima. This paper introduces Diversity Guided Evolutionary Programming, a novel approach to combine the best of both these research directions. This scheme incorporates diversity guided mutation, an innovative mutation scheme that guides the mutation step size using the population diversity information. It also takes some extra diversity preservative measures to maintain adequate amount of population diversity in order to assist the proposed mutation scheme. An extensive simulation has been done on a wide range of benchmark numeric optimization problems and the results have been compared with a number of recent evolutionary systems. Experimental results show that the performance of the proposed system is often better than most other algorithms in comparison on most of the problems.  相似文献   
89.
The electrochemical reduction of NO in alkaline solutions was investigated at gas diffusion electrodes with various metal (Ru, Rh, lr, Pd and Pt) catalysts at various NO flow rates. Reduction currents are observed at potentials more negative than 0.95 V, which increase with the decrease in potential and also with increasing gas flow rate. The faradaic efficiencies of N2O formation decrease with decreasing NO flow rate and with decrease in potential. The faradaic efficiencies of N2 formation increase with decreasing flow rate and with decrease in potential. The reduction of NO to N2 at a flow rate of 5mlmin–1 occurs selectively at potentials more negative than 0.1V; the faradaic efficiency of N2 formation is approximately 95 at Pd catalysts.Electricity production and NO decomposition can be carried out simultaneously using an H2NO fuel cell reactor. The faradaic efficiency of N2 formation at a flow rate of 5mlmin–1 is approximately 80 at a cell voltage of 0.25 V.  相似文献   
90.
Linoleic and linolenic acid hydroperoxides in malt, mash, or wort were determined with high sensitivity and high selectivity by the chemiluminescence-high performance liquid chromatography (CL-HPLC) method using isoluminol-microperoxidase solution as a luminescing reagent. The determination limit of this method for both hydroperoxides was 0.1 μM in mash or wort. During the mashing in a laboratory mash bath, the hydroperoxides started to increase just after mashing-in, reached a maximum at 65°C, and then decreased. Though the hydroperoxides were detected in mash just before the lautering in a pilot scale brewing, they disappeared during the lautering and could not be detected during the subsequent stages of wort production. Therefore, it was thought that the mashing process is the most important of the lipid oxidation reactions during wort production. It is also expected that the CL-HPLC method can give useful information on lipid oxidation mechanisms during wort production.  相似文献   
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