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51.
Case-based reasoning (CBR) is based on the use of past experience in finding the solution to a new but similar problem. CBR is composed of five main phases: input of the new problem, retrieval of the most similar cases from the knowledge base, adaptation of retrieved cases, validation of the new solution, and learning of the system by adding the approved solution to the knowledge base. Adaptation is the most difficult and the most important step in the successful use of the CBR strategy. Two adaptation methods that are based on fuzzy and rough sets are presented in this paper. The given example illustrates selection of a vibrofluidized bed (VFB) dryer, determination of a drying time, and evaluation of the final moisture content based on application of both adaptation methods.  相似文献   
52.
Vegetables used by the people of Assam (India) found to be highly nutritious to maintain general balance diet. Nutritional information is used increasingly by public agencies and agricultural industries to promote different traditional fresh product. The work aimed at determining few nutritionally important minerals (calcium, iron, magnesium, phosphorus, and potassium) in leafy green vegetables widely consumed in Assam. The objective of the present work was to examine the variability in the mineral content.  相似文献   
53.
This study aimed to evaluate retention of folate in vegetables caused by different processes used in modern large-scale service systems and the food industry. The concentration of folates present in raw samples of peas, broccoli and potatoes was measured during different cooking methods, warm and cold holding and reheating. The main folate forms in vegetables, tetrahydrofolates and 5-methyltetrahydrofolates, were analysed using a validated high-performance liquid chromatography (HPLC) method.  相似文献   
54.
A sensitive method for the determination of the herbicides nitralin and oryzalin by adsorptive stripping voltammetry (AdSV) at a hanging mercury drop electrode (HMDE) (pH 6.0) was described. The cyclic voltammograms demonstrate the adsorption of these compounds at the mercury electrode. A symmetric study of the various operational parameters that affect the stripping response was carried out by differential pulse voltammetry. With an accumulation potential of −0.5 V and a 80 s accumulation time, the limit of detection was 2.47 × 10−8 mol/L and 1.5 × 10−8 mol/L, the relative standard deviation (n = 10), correlation coefficient values 1.14%, 0.998, 1.48%, 0.999 at concentration levels of 8.3 × 10−8 mol/L to 1.5 × 10−6 mol/L and 2 × 10−8 mol/L to 1.0 × 10−5 mol/L for both compounds. The degree of interference of some other pesticides on the differential pulse adsorptive stripping signal for nitralin and oryzalin was evaluated. Finally the proposed method was applied for determination of nitralin and oryzalin in agricultural formulations, vegetables and grape juice samples.  相似文献   
55.
Emerging evidence strongly suggests that dietary nitrate, derived in the diet primarily from vegetables, could contribute to cardiovascular health via effects on nitric oxide (NO) status. NO plays an essential role in cardiovascular health. It is produced via the classical L-arginine–NO-synthase pathway and the recently discovered enterosalivary nitrate–nitrite–NO pathway. The discovery of this alternate pathway has highlighted dietary nitrate as a candidate for the cardioprotective effect of a diet rich in fruit and vegetables. Clinical trials with dietary nitrate have observed improvements in blood pressure, endothelial function, ischemia-reperfusion injury, arterial stiffness, platelet function, and exercise performance with a concomitant augmentation of markers of NO status. While these results are indicative of cardiovascular benefits with dietary nitrate intake, there is still a lingering concern about nitrate in relation to methemoglobinemia, cancer, and cardiovascular disease. It is the purpose of this review to present an overview of NO and its critical role in cardiovascular health; to detail the observed vascular benefits of dietary nitrate intake through effects on NO status as well as to discuss the controversy surrounding the possible toxic effects of nitrate.  相似文献   
56.
The majority of children in the U.S. do not consume enough fruits and vegetables (FV). Children’s liking of and preferences for FV are consistent predictors of intake, as are factors such as availability and accessibility, which are largely under the control of parents and caregivers. This study was designed to examine parents’ and caregivers’ current purchasing habits regarding child-friendly (CF)-shaped foods and pre-cut produce; determine their sensory perceptions of CF-shaped vs. regular-shaped pre-cut FV; and, to ascertain their willingness to pay slightly more for CF-shaped FV compared to fresh, whole produce. Healthy, CF-shaped fruit and vegetable snacks were developed by cutting FV into CF shapes (butterfly, chick, flower, teddy bear). Participants (n = 298) were adults, the majority of whom (66.1%) reported having children at home. Participants who reported having children at home consistently recognized CF-shaped fruit and vegetable samples as CF-shaped foods, while 64.4% of participants with children at home perceived regular-shaped pre-cut fruit and vegetable samples as CF-shaped foods. Participants rated CF-shaped samples as more visually appealing than regular-shaped samples, (p < 0.0001) and were 34% more likely to select CF-shaped samples. Female gender, the presence of children in the home, and frequent self-reported purchase of pre-cut produce were also significant positive predictors of visual appeal. Taste and texture ratings were not consistently significantly higher for CF-shaped fruit and vegetable samples. CF shape predicted higher willingness to pay extra for the fruit and vegetable product (p = 0.0057), as did frequent purchase of pre-cut produce and CF-shaped foods. Adults, particularly females and individuals with children in the household, find CF-shaped FV highly visually appealing and are willing to pay slightly more for these foods. Healthy, ready-to-eat, CF-shaped fruit and vegetable snacks may be a promising marketing strategy to help increase fruit and vegetable intake among children.  相似文献   
57.
In this study, we considered the efficacy of seed treatments for the inactivation of some seedborne viruses in tomato, pepper, melon, squash, bean and lettuce seeds, which are essential for human nutrition and seed production in our country. A total of 325 seed samples obtained from various farmers and foundations were tested by DAS-ELISA and RT-PCR procedures. Eight seed lots infected with Tomato mosaic tobamovirus (ToMV), Tobacco mosaic tobamovirus (TMV), Cucumber mosaic cucumovirus (CMV), Soybean mosaic potyvirus (SMV) and Lettuce mosaic potyvirus (LMV) were selected as research materials. Virus inactivation treatments were made by using acetic acid (CH3COOH), hydrogen peroxide (H2O2), hydrochloric acid (HCl), sodium hypochlorite (NaClO), Triton X 100, dry heat, heated water, ozone (O3), and UV (305 nm wavelength). The most effective treatments for reducing virus concentration were HCl, heated water (65 °C) and ozone (10 g m?3). These treatments reduced concentrations of seed-borne viruses in ranges of 51%, 42%, and 32%, respectively. Other treatments were less effective and reduced virus concentrations in the range of 27%–12%. HCl and ozone treatments were the most effective and applicable methods because they did not have negative effect on seed germination.  相似文献   
58.
Min Zhang  Hao Jiang 《Drying Technology》2014,32(15):1743-1750
Drying of fresh produce and marine products to develop high-quality dried products cost-effectively has been the theme of extensive research carried out at the School of Food Science & Technology of Jiangnan University, Wuxi, China. Both conventional and innovative hybrid drying techniques encompassing the enhancement of drying rates and quality through utilization of modern ultrasonic and nanotechnology have been examined in detail and reported in the open literature. Some of the work was funded by the industry and eventually utilized in industrial-scale processing. The objective of this article is to summarize the key developments for a wider global readership. An outline of ongoing drying R&D will be provided in the closing section.  相似文献   
59.
Heavy metal contamination of soils resulting from mining and smelting is causing major concern due to the potential risk involved. This study was designed to investigate the heavy metal (Cu, Zn, Pb and Cd) concentrations in soils and food crops and estimate the potential health risks of metals to humans via consumption of polluted food crops grown at four villages around the Dabaoshan mine, South China. The heavy metal concentrations in paddy and garden soils exceeded the maximum allowable concentrations for Chinese agricultural soil. The paddy soil at Fandong village was heavily contaminated with Cu (703 mg kg− 1), Zn (1100 mg kg− 1), Pb (386 mg kg− 1) and Cd (5.5 mg kg− 1). Rice tended to accumulated higher Cd and Pb concentration in grain parts. The concentrations of Cd, Pb and Zn in vegetables exceeded the maximum permissible concentration in China. Taro grown at the four sampled villages accumulated high concentrations of Zn, Pb and Cd. Bio-accumulation factors for heavy metals in different vegetables showed a trend in the order: Cd > Zn > Cu > Pb. Bio-accumulation factors of heavy metals were significantly higher for leafy than for non-leafy vegetable. The target hazard quotient (THQ) of rice at four sites varied from 0.66-0.89 for Cu, 0.48-0.60 for Zn, 1.43-1.99 for Pb, and 2.61-6.25 for Cd. Estimated daily intake (EDI) and THQs for Cd and Pb of rice and vegetables exceeded the FAO/WHO permissible limit. Heavy metal contamination of food crops grown around the mine posed a great health risk to the local population through consumption of rice and vegetables.  相似文献   
60.
目的建立基于QuEChERS与液相串联质谱(liquidchromatographytandemmassspectrometry,LC-MS/MS)联用技术快速测定蔬菜水果中氟吗啉和烯酰吗啉残留量的分析方法。方法样品经乙腈提取后,用QuEChERS法净化, Symmetry C18色谱柱分离, LC-MS/MS外标法定量。结果方法学验证,该方法具有较高的灵敏度,氟吗啉和烯酰吗啉的检出限为0.05μg/kg,定量限为0.1μg/kg;在0.1~25μg/kg浓度范围,线性相关系数大于等于0.9963,回收率在82.4%~106.3%之间,相对标准偏差为1.5%~8.8%,该方法具有较好的回收率和良好的再现性,满足国家相关标准要求。结论该方法处理过程快速简便,灵敏度高、专属性强。  相似文献   
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