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161.
The environmental sustainability of the current global energy system is under serious question. A major transition away from fossil fuels to one based on energy efficiency and renewable energy is required.The development of a wide range of renewable energy technologies is continuing at an impressive rate. Cost reductions have been real and impressive. With few exceptions however, the relative contribution of renewable energy to the total energy mix remains quite small in most countries. There are still a wide range of barriers preventing renewables from making a much more significant contribution.The paper utilises a range of case studies from around the world which demonstrate some of the lessons of successful renewable energy implementation, and suggest a set of coordinated policies which would lead to a growing role for renewable energy in the commercial energy market. 相似文献
162.
In a companion article we have reviewed a number of available modelling approaches employed in estimating the influence of age, period and cohort effects on chronic disease rates. Here we review some of the graphical methods for displaying disease rates with a view to extracting information about the separate and joint effects of age, period and cohort. The more traditional displays such as line charts are compared to approaches based on smoothing and two- and three-dimensional plots which have recently been proposed. Other graphical techniques which are principally concerned with displaying interactions, such as biplots and correspondence analysis, are also considered. These techniques are illustrated with examples to compare the techniques revealing their strengths and weaknesses. It is clear that graphical approaches can be useful tools in understanding the behaviour of chronic disease time trends. 相似文献
163.
cDNA cloning and characterization of A3i, an alternatively spliced rat A3 adenosine receptor variant
Programmed cell death of antigen specific T cells (apoptosis) may be an important process in the pathogenesis of autoimmune diseases such as multiple sclerosis (MS). Fas antigen was recognized as an apoptosis-related antigen. To investigate Fas antigen in multiple sclerosis (MS), we measured the expression rate of Fas antigen and activation markers on T cells in peripheral blood (PB) of 19 MS patients, 18 controls and in cerebrospinal fluid (CSF) of nine MS patients by flow cytometry. The positive rate of Fas antigen in MS patients was higher than that of healthy controls in PB. In patients with MS, the expression rates of Fas antigen and activation markers were higher in CSF than in PB. The above findings suggest that there is acceleration or impairment of apoptosis on activated T cells in MS. 相似文献
164.
WA Zatonski AB Lowenfels P Boyle P Maisonneuve HB Bueno de Mesquita P Ghadirian M Jain K Przewozniak P Baghurst CJ Moerman A Simard GR Howe AJ McMichael CC Hsieh AM Walker 《Canadian Metallurgical Quarterly》1997,89(15):1132-1138
BACKGROUND: There are few previous epidemiologic studies of gallbladder cancer, a rare but nearly always lethal gastrointestinal cancer with a demonstrated greater frequency in adult women and older subjects of both sexes, and also in the members of populations throughout central and eastern Europe and certain racial groups such as native American Indians. Unfortunately, the prospects for the prevention of this form of cancer are poor. PURPOSE: Our purpose in conducting this study was to investigate possible new risk factors for gallbladder cancer and to strengthen our understanding of established causal agents that may be involved in this disease. METHODS: A large, collaborative, multicenter, case-control study of cancer of the gallbladder was conducted in five centers located in Australia (Adelaide), Canada (Montreal and Toronto), The Netherlands (Utrecht), and Poland (Opole) from January 1983 through July 1988. Case subjects with gallbladder cancer were accrued by the centers from hospital pathology records and from reports to regional cancer registries. Cancer diagnosis was confirmed by either biopsy, cholecystectomy, or at the time of autopsy. Control subjects were randomly assigned at each center from the population. The pooled analysis included 196 case subjects and 1515 control subjects (who did not report previous cholecystectomy). Ninety-eight percent of the subjects were white. Personal interviews of case subjects, control subjects, and surrogates (spouse or next of kin) were conducted by trained personnel. RESULTS: After adjusting for potential confounding factors (age, sex, center, type of interview, years of schooling, alcohol intake, and lifetime cigarette smoking), a history of gallbladder symptoms requiring medical attention (e.g., reduced bile secretion from the gallbladder into the small intestine due to obstructions of the common bile or cystic ducts) was the major risk factor associated with this form of cancer (odds ratio [OR] = 4.4; 95% confidence interval [CI] = 2.6-7.5). This association was present even in subjects who had their first gallbladder examination because of symptoms present more than 20 years earlier (OR = 6.2; 95% CI = 2.8-13.4). Other variables associated with gallbladder cancer risk included an elevated body mass index, high total energy intake, high carbohydrate intake (after adjustment for total energy intake), and chronic diarrhea. All of these risk factors have been previously associated with gallstone disease. CONCLUSIONS: These findings are consistent with a major role of gallstones, or risk factors for gallstones, in the cause of gallbladder cancer. Additional information on whether or not screening high-risk subjects for gallstones or gallbladder cancer is needed. 相似文献
165.
166.
In this paper a simple method of deriving lower bound limit loads for thin plates is presented. This method is based on the method of elastic compensation, an iterative elastic technique, which has recently been extended to allow the analysis of structures using thin shell finite element analysis using generalised yield criteria. Here the method is modified to allow analysis of plates, including the effects of transverse shear. The elastic compensation method, combined with generalised yield criteria, is implemented using the finite element numerical analysis technique. Convergence studies are carried out and limit loads are obtained for a range of geometries, boundary conditions and loading. The calculated limit loads are compared with results available in the literature and with new elasto-plastic results and show that the method can be used to quickly obtain practical results. 相似文献
167.
A portable respirometer has been used to measure oxygen uptake and production rates, by fixed and suspended organisms in an East Devon river which receives papermill effluent. Benthic respiration dominates the oxygen balance in the stretch most affected by the effluent and increases the effective BOD decomposition rate by a factor of up to 12: Values of decomposition rate of 3.5–4.5 (day−1) have been measured in the stream. 相似文献
168.
VK O'Donnell E Smitsaart B Cetra S Duffy J Finelli D Boyle G Draghi N Fondevila AA Schudel 《Canadian Metallurgical Quarterly》1997,16(3):833-840
The analysis of sera obtained from animals vaccinated or revaccinated with inactivated vaccines against foot and mouth disease (FMD) virus showed that these vaccines induced antibodies against the virus infection-associated (VIA) antigen, detectable by agar gel immunodiffusion (AGID). The present study evaluates the antibody response to protein 3D and the VIA antigen (VIAA) of FMD virus induced by different vaccines in a group of 51 calves. This response was detected using AGID and a liquid-phase blocking sandwich enzyme-linked immunosorbent assay (ELISA) for anti-3D antibodies (ELISA-3D). No anti-VIAA or anti-3D antibodies were detected after the initial vaccination. Following revaccination, animals giving positive results were detected by both methods. This immune response disappeared 60-120 days post-revaccination (dprv) according to the AGID method, and 90-180 dprv when ELISA-3D was used. Samples of oesophageal-pharyngeal fluid obtained from animals that remained positive for anti-VIAA antibodies at 90-120 dprv gave negative results for viral isolation, indicating that the transitional antibody response induced by the vaccine was due to the presence of non-structural antigens in the vaccine and not to viral infection. These results indicate that the ELISA-3D method could be used as a complementary method for sero-epidemiological studies as an indirect indicator of viral activity, as long as the age and vaccination status of the animals being sampled are taken into consideration. 相似文献
169.
RF Heller RJ Walker CA Boyle DL O'Connell S Rusakaniko AJ Dobson 《Canadian Metallurgical Quarterly》1994,161(9):529-531
OBJECTIVE: To compare two interventions for reducing dietary fat intake in first degree relatives of recent heart attack victims. DESIGN: A randomised controlled trial comparing a low cost mail-out advice program; referral to a general practitioner (GP); and no intervention (control group). PARTICIPANTS: Adult children or siblings, aged less than 70 years, of survivors of definite or suspected heart attack who had been admitted to hospitals in the Lower Hunter Region of New South Wales. MAIN OUTCOME MEASURES: Dietary fat intake (evaluated with a validated short questionnaire) and measurement of blood cholesterol levels at six months. RESULTS: Of the 342 relatives who participated (36% of those invited), 109, 120 and 113, respectively, were randomly assigned to receive a mail-out intervention, advice from their GP or to be part of a control group. The six-month follow-up questionnaire was completed by only 59% of those in the mail-out intervention group compared with 71% of the GP group and 77% of the control group. Younger participants, cigarette smokers and children (compared with siblings) were less likely to return a follow-up questionnaire. The mail-out group showed a statistically significant 20% reduction in self-reported dietary fat intake, but this was not seen in either the GP group or the controls. The low response rate meant the study had insufficient power to detect hypothesised changes in blood cholesterol. CONCLUSION: Because of the poor response rate and possible biases from a differential response to follow-up, we conclude that this low intensity intervention for relatives of people with recent heart attack produces only a modest improvement in reported dietary fat intake. Alternative strategies may be more effective in reducing the risk of heart disease. 相似文献
170.
T Zheng TR Holford Y Chen BA Jones J Flannery P Boyle 《Canadian Metallurgical Quarterly》1997,33(1):96-100
BACKGROUND: Surgical procedures used to remove genital warts (cryotherapy, electrodesiccation) are painful. Attempts to reduce the discomfort of surgery by prior lidocaine infiltration anesthesia are compromised by the pain of the infiltration. OBJECTIVE: Our purpose was to determine the efficacy of topically applied lidocaine/prilocaine cream to reduce the pain of lidocaine infiltration and the pain associated with cryotherapy to remove genital warts. METHODS: Men, scheduled for removal of genital warts by cryotherapy, were randomly selected to receive one of three treatments: (1) lidocaine/prilocaine cream application, (2) 1% lidocaine infiltration, and (3) lidocaine/prilocaine cream application followed by infiltration of 1% lidocaine. RESULTS: Application of lidocaine/prilocaine cream for 15 minutes markedly reduced the pain of lidocaine infiltration. The combination of lidocaine/prilocaine cream followed by infiltration of 1% lidocaine gave greater pain relief from the cryotherapy than did either anesthetic alone. CONCLUSION: The application of lidocaine/prilocaine cream as an adjunct to lidocaine infiltration reduced the pain of infiltration and the pain associated with cryotherapy for the removal of genital warts. 相似文献