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This review examines the application, limitations, and potential alternatives to the Hagberg–Perten falling number (FN) method used in the global wheat industry for detecting the risk of poor end-product quality mainly due to starch degradation by the enzyme α-amylase. By viscometry, the FN test indirectly detects the presence of α-amylase, the primary enzyme that digests starch. Elevated α-amylase results in low FN and damages wheat product quality resulting in cakes that fall, and sticky bread and noodles. Low FN can occur from preharvest sprouting (PHS) and late maturity α-amylase (LMA). Moist or rainy conditions before harvest cause PHS on the mother plant. Continuously cool or fluctuating temperatures during the grain filling stage cause LMA. Due to the expression of additional hydrolytic enzymes, PHS has a stronger negative impact than LMA. Wheat grain with low FN/high α-amylase results in serious losses for farmers, traders, millers, and bakers worldwide. Although blending of low FN grain with sound wheat may be used as a means of moving affected grain through the marketplace, care must be taken to avoid grain lots from falling below contract-specified FN. A large amount of sound wheat can be ruined if mixed with a small amount of sprouted wheat. The FN method is widely employed to detect α-amylase after harvest. However, it has several limitations, including sampling variability, high cost, labor intensiveness, the destructive nature of the test, and an inability to differentiate between LMA and PHS. Faster, cheaper, and more accurate alternatives could improve breeding for resistance to PHS and LMA and could preserve the value of wheat grain by avoiding inadvertent mixing of high- and low-FN grain by enabling testing at more stages of the value stream including at harvest, delivery, transport, storage, and milling. Alternatives to the FN method explored here include the Rapid Visco Analyzer, enzyme assays, immunoassays, near-infrared spectroscopy, and hyperspectral imaging.  相似文献   
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Reports an error in "Recovery of spatial alternation deficits following selective hippocampal destruction with kainic acid" by J. Patrick Kesslak and Fred H. Gage (Behavioral Neuroscience, 1986[Apr], Vol 100[2], 280-283). In the aforementioned article, the degrees of freedom reported in the Results section are incorrect. In the sixth paragraph on page 281, the second sentence should read as follows: Results of the ANOVA indicated a significant effect for surgical treatments. F(2, 25)=25.44, p1986-21445-001.) Examined whether the sympathetic ingrowth of superior cervical ganglion (SCG) fibers sprouting into the hippocampus following kainic acid (KA) lesion of CA3 and CA4 pyramidal cells in male Sprague-Dawley rats would contribute to behavioral recovery. 31 Ss were trained on a forced-choice task. After reaching criterion performance levels, Ss received either KA (8 nM/0.4 μl) or saline injections into the hippocampus and were again tested on the forced-choice task. Half of the Ss had their SCG removed 35 days after injections, and all were again tested on the forced-choice task. Analysis of variance (ANOVA) showed Ss receiving KA took significantly longer to reach criterion following injections. Removal of the SCG after recovery reintroduced the performance deficit of KA-treated Ss on the alternation task; no other group showed any effect for SCG removal. Results indicate that the SCG may have a modulatory effect in behavioral recovery, although other mechanisms may also be operating. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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通过深层搅拌与喷锚技术在珠海明星大厦基坑支护中的应用,对实验结果进行分析研究。  相似文献   
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通过论述重型工业厂房和大面积地面堆载仓库对基产生的不良影响,介绍用水泥-水玻璃化学灌浆进行全面加固,具有快速,有效,经济等优点,值得推广使用。  相似文献   
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Recent studies have suggested that factors in the target tissue influence the degree of plasticity and regeneration following aging and/or specific insults. We have investigated whether young or aged targets differ in their noradrenergic innervation from fetal locus coeruleus (LC) neurons, and also if a specific growth factor, glial cell line-derived neurotrophic factor (GDNF) can affect this innervation pattern. Tissue pieces of fetal brainstem and young (3 months) or old (18 months) iris tissue were transplanted simultaneously into the anterior chamber of the eye of adult hosts. We found that aged iris transplants became innervated to a significantly lesser degree by the cografted LC neurons than young iris transplants. Fetal hippocampal tissue was then grafted to adult hosts, and a fetal brainstem graft containing LC neurons was placed adjacent to the first graft, either at 3 or 21 months post-grafting. Thus, old/young chimeras of the noradrenergic coeruleo-hippocampal pathway were created. Aged hippocampal grafts received a much less dense innervation from co-grafted LC neurons than young hippocampal grafts. Tyrosine hydroxylase-positive-immunoreactive innervation was only found in the outskirts of aged grafts, while the young hippocampal grafts contained an even innervation pattern. The innervation density of hippocampal grafts was significantly enhanced by GDNF treatment. These findings demonstrate that target-derived factors may regulate neuronal plasticity, and that the age of the target is more important for innervation properties than the age of the neuron innervating a particular target.  相似文献   
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BACKGROUND: In Citrus the inhibitory effect of fruit on flower formation is the main cause of alternate bearing. Although there are some studies reporting the effect on flowering of the time of fruit removal in a well‐defined stage of fruit development, few have investigated the effect throughout the entire fruit growth stage from early fruitlet growth to fruit maturity. The objective of this study was to determine the phenological fruit developmental stage at which the fruit begins its inhibitory effect on flowering in sweet orange by manual removal of fruits, and the role of carbohydrates and nitrogen in the process. RESULTS: Fruit exerted its inhibitory effect from the time it was close to reaching its maximum weight, namely 90% of its final size (November) in the present experiments, to bud sprouting (April). The reduction in flowering paralleled the reduction in bud sprouting. This reduction was due to a decrease in the number of generative sprouted buds, whereas mixed‐typed shoots were largely independent of the time of fruit removal, and vegetative shoots increased in frequency. The number of leaves and/or flowers per sprouted shoot was not significantly modified by fruit load. CONCLUSION: In ‘Valencia’ sweet orange, fruit inhibits flowering from the time it completes its growth. Neither soluble sugar content nor starch accumulation in leaves due to fruit removal was related to flowering intensity, but some kind of imbalance in nitrogen metabolism was observed in trees tending to flower scarcely. Copyright © 2010 Society of Chemical Industry  相似文献   
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汪洪涛  陈成  余芳  陈宝宏 《食品与机械》2015,31(1):30-32,163
研究青豆、黑豆和黄豆发芽过程中营养成分的变化规律,为发芽大豆食品生产和加工提供试验依据。采用一定的温度与湿度对大豆发芽条件进行控制,定期抽样测定发芽大豆中的粗蛋白、粗脂肪、还原糖、Vc和异黄酮的含量。结果表明:与发芽1d后相比,发芽7d后青豆、黄豆、黑豆中蛋白质含量分别比发芽1d后增加了24.03%,24.28%,22.88%,还原糖含量分别增加了129.06%,127.17%,125.73%,VC的含量分别增加了831.37%,663.97%,807.07%,粗脂肪的含量分别减少了37.28%,35.68.28%,36.69%。3种大豆都在发芽4d后异黄酮的含量达到最大值,其中黑豆中异黄酮的含量最高为0.531%。  相似文献   
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