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1.
交叉试验     
发生了质量事故,是设备、操作等硬件的缘故,抑或药液的缘故?通过交叉试验的故事,把真相找了出来。  相似文献   
2.
Several frameworks incorporate social and psychological elements of environmentally significant behaviour, and most assume cognitive and deliberate decision-making. Household energy consumption behaviours, however, span a spectrum from reasoned and deliberate to unplanned and automatic. The aim of this paper is to advance knowledge of reasoned and unplanned behaviours in the context of pro-environmental action. Using results of a survey administered to occupants of an urban residential green building, this study explores five household consumption behaviours and tests the hypothesis that unplanned behaviours will be poorly predicted by a reasoned, values-based behavioural framework. Using path analyses, variables in a values-based framework are used to predict surveyed behaviours. Findings indicate that behaviours hypothesized to be unplanned were not well predicted by the values-based framework. The framework successfully predicted what was hypothesized to be a fully reasoned behaviour. Three potential reasons are discussed for the lack of prediction of some behaviours. A deeper understanding of how unplanned, automatic or habitual behaviours intervene in conservation intentions can help policy-makers and building designers better respond to influences of occupant behaviour on building performance.  相似文献   
3.
The susceptibility of 16 noncompetitive cardiac pacemakers to radiation from a powerful radar system was investigated in the laboratory and in the vicinity of its prototype. From comparative in vitro tests in air, fat, water, and saline it was concluded that only tests in fat or air represent the worst case condition after implantation. In air all pacemakers showed signs of interference at pulse power densities between 0.025 mW/cm2 and 62.5 mW/CM2. Three of six implanted pacemakers were triggered or inhibited depending on their mode of operation when tested at a location 1.2 km away from the radar station by the radar beam occurring every 5.5 sec. Because interfering radiation can enter the pacemaker circuitry directly along the electrode, acting as an antenna, metal encapsulation of the pulse generator does not provide sufficient shielding against microwave radiation. However, pacemakers modified by metal encapsulation and a low-pass filter at the electrode remained undistrubed at pulse power densities of greater than 10 W/cm2 when tested under worst case condition in air.  相似文献   
4.
5.
The purpose of this retrospective study was to evaluate the utility of routine measurement of amniotic fluid alpha-fetoprotein levels at the time of second trimester genetic amniocentesis (mean gestational age, 17.3 weeks +/- 2.5 weeks standard deviation; median, 16.8 weeks; range, 15 to 22 weeks). During the study period 7174 patients underwent second trimester genetic amniocentesis. Outcome data were available in all cases. In 79 (1.1%) cases the amniotic fluid alpha-fetoprotein level was > or = 2.0 multiples of the median. Thirty-three of the 79 (42%) patients had normal ultrasonograms, and in 31 of 33 (94%) the amniotic fluid alpha-fetoprotein level was between 2.0 and 3.0 multiples of the median. Forty-six of the 79 (58%) patients had abnormal ultrasonographic findings, and of these, 82% were neural tube defects, abdominal wall defects, or cystic hygromas. Acetylcholinesterase was positive in 37 cases, all of which had abnormal ultrasonographic findings. None of the fetuses with negative findings on sonographic screening had detectable abnormalities at birth. In this study, with over 7000 patients, amniotic fluid alpha-fetoprotein and acetylcholinesterase levels did not increase the detection of fetal abnormalities. On the basis of these results, routine measurement of amniotic fluid alpha-fetoprotein level at the time of routine genetic amniocentesis (15 to 22 weeks) does not appear justified.  相似文献   
6.
BACKGROUND/AIMS: In the current state of knowledge of the pathophysiology of hepatic encephalopathy, a reduction in hyperammonemia is the most important evidence of effective treatment. Therefore, the therapeutic efficacy of oral L-ornithine-L-aspartate, which improves impaired ammonia detoxification, was investigated in patients with cirrhosis, hyperammonemia and stable, overt, chronic hepatic encephalopathy, and in subclinical hepatic encephalopathy in a randomized, double-blind, placebo-controlled clinical trial. METHODS: Oral L-ornithine-L-aspartate was administered three times daily at fixed times for 14 consecutive days in a total dose of 18 g per day. The design was chosen to prevent an increase in ammonia induced by a protein meal of 0.25 g/kg body weight, given at the start of the daily treatment period. Efficacy variables were: fasting and postprandial ammonia concentration, Number-Connection-Test time, mental state grades, and a Portosystemic Encephalopathy Index. Analyses were based on the total study sample of 32 placebo- and 34 L-ornithine-L-aspartate-treated patients as well as on the subgroup samples in the overt (20 placebo- and 23 L-ornithine-L-aspartate-treated) and subclinical hepatic encephalopathy (12 placebo- and 11 L-ornithine-L-aspartate-treated) patients. RESULTS: Number Connection Test performance times (p<0.01) as well as fasting (p<0.01) and postprandial (p<0.05) venous blood ammonia concentrations in the L-ornithine-L-aspartate-treated group showed improvement in comparison to placebo. Also, the mental state grade (p<0.05) and the Portosystemic Encephalopathy Index (p<0.01), improved to a much greater degree in the L-ornithine-L-aspartate group than in the placebo group. Adverse events were observed in neither the placebo nor the L-ornithine-L-aspartate-treated patients. CONCLUSION: Oral L-ornithine-L-aspartate is a safe, well-tolerated treatment with a good compliance rate and a beneficial therapeutic effect in patients with cirrhosis and stable, overt, chronic hepatic encephalopathy.  相似文献   
7.
Molsidomine was shown to have a strong pain-relieving action in 22 coronary patients investigated one hour after oral intake of 2 mg of the substance. During comparable maximal exercise load the ST interval lowering was reduced from an average of 0.22 mV to 0.09 mV (P less than 0.0005). At the termination of exercise it was still reduced from 0.23 mV to 0.12 mV (P less than 0.0005). At the same time the exercise tolerance increased from 570 to 717 Watt-minutes (P less than 0.0025). Pectanginal complaints were clearly reduced at the same exercise loads, 11 patients became symptom-free at the same load. Even when exercise loading was stopped at higher loads a decrease of the severity of angina pectoris could be shown. Seven patients became symptom-free at that stage. The heart rate was not influenced markedly at rest and during exercise. Systolic blood pressure was reduced from 135 mm Hg to 118 mm Hg (P less than 0.0005), and in comparable submaximal loads from 177 to 165 mm Hg (P less than 0.005).  相似文献   
8.
淀粉微胶囊改善香精在洗衣粉中的作用与功效   总被引:1,自引:0,他引:1  
采用光离子检测仪(PID)、溶剂萃取和评香的方法测定评估了淀粉微胶囊增强香精在洗衣粉中的作用及提高香精在储存过程中稳定性的功效.结果表明,当淀粉微胶囊包裹香精与液体香精复配使用时,即使在香精总量较低时,仍能够增强香精在洗涤过程中及漂洗后的表现力.淀粉微胶囊包裹香精能有效地提高挥发性香原料在45℃条件下的储存稳定性.  相似文献   
9.
通过"临时"法庭的故事,作者表达这样一个观点在寻找事故的原因时,符合宏观逻辑行为是断案的第一依椐.  相似文献   
10.
围挠着"为了那个窄窄的板边"所展开的故事,展现在读者面前是守旧、一成不变与求新、与时俱进两种观点的矛盾与斗争。  相似文献   
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