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61.
News     
J. Farkas 《Scientometrics》1989,15(5-6):633-638
This section ofScientometrics will carry fresh and reliable news of people, programs, recent and forthcoming meetings and publications etc. Its effectiveness depends greatly on your assistance. Items for inclusion should be submitted to the Co-ordinating Editor, Dr.J. Farkas.With the assistance ofJudith Balázs Library of the Hungarian Academy of Sciences, Budapest, Hungary.  相似文献   
62.
In M. Weiser's (ibid., pp. 19-25) vision of ubiquitous computing, computers will disappear from conscious thought. From a hardware perspective, the authors examine how far we've succeeded in implementing this vision and how far we have to go.  相似文献   
63.
In the present work, a thermal evaluation and optimisation for the components of a solar water heating system was studied. An implicit graphical method was developed to estimate the optimum Ac and V on the basis of the load requirements as well as maximum system efficiency. This method depends on the temperature of hot water extracted for the load, as well as the annual solar factor. The developed method was applied to estimate the optimum dimensions when a daily quantity of hot water (175 l) at 60°C was extracted. The final results showed that with the given load requirements and a solar factor 70%, the optimum Ac and V were 16 m2 and 700 l, respectively.  相似文献   
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AIM OF THE STUDY: The prevention of diabetic nephropathy is as yet an unresolved issue. The aim of our study was to assess the effects of transplantation of long-term cultured and cryopreserved fetal pancreas islets on metabolic control and the development of diabetic nephropathy. METHODS: Serum C-peptide, glucose, HbA1c, insulin requirements, urinary albumin excretion rate, and blood pressure of 10 insulin-dependent diabetic patients after transplantation were compared with a group of 27 insulin-dependent diabetic controls on insulin therapy only during a 10-year follow-up. RESULTS: In the first year after transplantation mean insulin requirement decreased from 53.6+/-2.2 to 35.8+/-1.2 units. C-peptide levels appeared (0.55+/-0.08 ng/ml) and remained detectable throughout the follow-up. Blood glucose and HbA1c were significantly (P<0.05) lower than in the controls. Mean albumin excretion rates of the transplant and the control groups during the follow up were 18.8+/-8.5 and 11.7+/-2.0, 16.6+/-6.6 and 14.0+/-2.3, 15.0+/-5.0 and 15.1+/-2.7, 15.3+/-7.5 and 20.4+/-4.2, 19.8+/-6.2 and 36.7+/-11.1, 11.7+/-3.6 and 51.3+/-14.6, 14.1+/-4.2 and 71.4+/-23.1, 22.7+/-8.6 and 92.0+/-28.1, 18.0+/-5.9 and 107.6+/-35.6, 21.7+/-11.0 and 101.5+/-29.3 microg/min respectively. From the 6th year the difference between the two groups was significant (P<0.001). In the transplant group initial mean systolic and diastolic blood pressure values were 132.0+/-3.3 and 81.5+/-1.5 mmHg, in the controls 130.4+/-3.4 and 79.6+/-1.6 mmHg respectively. Significant changes (P<0.05) of blood pressure during the follow-up or differences between the two groups were not observed. CONCLUSIONS: We conclude that fetal islet transplantation is effective in achieving good long-term diabetes control and in the prevention of diabetic nephropathy.  相似文献   
65.
The objective of this work was to develop a near‐infrared reflectance spectrometry (NIRS) calibration estimating the tocopherol and phytosterol contents in sunflower seeds. Approximately 1000 samples of grinded sunflower kernels were scanned by NIRS at 2‐nm intervals from 400 to 2500 nm. For each sample, standard measurements of tocopherol and phytosterol contents were performed. The total tocopherol content was obtained by high‐performance liquid chromatography coupled with a fluorescence detector, while the total phytosterol content was assessed by gas chromatography. For tocopherol, the calibration data set ranged from 175 to 1005 mg/kg oil (mean value around 510 ± 140 mg/kg oil), whereas for the phytosterol content, the calibration data set ranged from 180 to 470 mg/100 g oil (mean value of 320 ± 50 mg/100 g oil). The NIRS calibration showed a relatively good correlation (R2 = 0.64) between predicted by NIRS and real values for the total tocopherol content but a poor correlation for the total phytosterol content (R2 = 0.27). These results indicate that NIRS could be useful to classify samples with high and low tocopherol content. In contrast, the estimation of phytosterol contents by NIRS needs further investigation. Moreover, in this study, calibration was obtained by a modified partial least‐squares method; the use of other mathematical treatments can be suitable, particularly for total phytosterol content estimation.  相似文献   
66.
A unique approach to attain enhanced, natural safety at low costs is given with a new, low temperature, low power level, nuclear energy plant of advanced design: the Geyser. The Geyser District Heating Nuclear Energy Plant (GDHNEP) and an ordinary low-temperature steam-cycle, the Geyser Thermal Energy Converter (GTEC), represent together a system possessing of remarkable features. Estimates project, that relatively small district heating plants distributed over a district heating network, or operating autonomously, would be cost effective. As a co-generation device the Geyser system may supply ample heating power and/or electricity opening new alternatives.  相似文献   
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Six female primary affective disorder patients who had gained an average of 9.5 kg while taking lithium lost an average of 2.9 kg on a 10-day 900 calorie a day hospital diet containing 100 mEq of sodium per day. No evidence of lithium toxicity was observed on this regimen. There was no evidence that fluid retention played a major role in the weight gain.  相似文献   
70.
Radiation decontamination of dry ingredients, herbs and enzyme preparations is a technically feasible, economically viable and safe physical process. The procedure is direct, simple, requires no additives and is highly efficient. Its dose requirement is moderate. Radiation doses of 3–10 kGy (0·3–1 mrad) have proved sufficient to reduce the viable counts to a satisfactory level.Ionising radiations do not cause any significant rise in temperature. The flavour, texture or other important technological or sensory properties of most ingredients are not influenced at radiation doses necessary for satisfactory decontamination, and radiation obviates the chemical residue problem.The microflora surviving radiation decontamination of dry ingredients are more susceptible to subsequent antimicrobial treatments. Recontamination can be prevented as the product can be irradiated in its final packaging. Irradiation could be carried out in commercial containers and would result in considerable savings of energy and labour as compared to alternative decontamination techniques.It appears that time is on the side of radiation. The demand for dry ingredients of good microbiological quality is ever-increasing and the food industries could well accommodate the cost of irradiation treatment. Radiation processing of these commodities is an established technology in several countries and more clearances on irradiated foods are expected to be granted in the near future.  相似文献   
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