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排序方式: 共有714条查询结果,搜索用时 15 毫秒
41.
为解决无重金属盐皮蛋易出现的碱伤、烂头等问题,改善无重金属盐皮蛋品质,本研究以鸡蛋为原料,采用清料法腌制皮蛋,加入葡萄糖、单宁、葡萄糖酸-δ-内酯三种非金属腌制剂,通过单因素实验选择最佳添加量,之后进行复配,以蛋清硬度、游离碱度、色度以及蛋黄硬化率为指标,结合腌制20 d皮蛋的感官评价及蛋壳微观结构,考察各复配...  相似文献   
42.
Brominated dioxins (PBDD/Fs) and 17 polybrominated diphenylether (PBDE) congeners including BDE-209 were analysed in 100 composite samples of commonly consumed foods of animal origin, prepared from ten to 40 individual subsamples of each type. These included 30 samples of milk from farms; eggs from chickens; fat from cows, pigs, sheep, and poultry; and liver from cows, pigs, sheep, horses, and poultry. The ISO 17025-accredited analytical methodology used, follows similar guidelines as given for chlorinated dioxins and polychlorinated biphenyls (PCBs) in European Commission Directive 2002/69/EC. Apart from some samples of milk, PBDD/Fs and PBDEs were detected in all food types. Concentrations ranged from 0.31 µg kg?1 Σ17 PBDEs for a sample of milk to 37.5 µg kg?1 Σ17 PBDEs for a sample of liver. The corresponding range for the PBDD/F toxicity (computed using analogous PCDD/F toxic equivalency factors (TEFs)) was 0.09 ng TEQ kg?1 to approximately 3.5 ng TEQ kg?1. The detection of these compounds, in particular PBDD/Fs, is consistent with the increased use and disposal of brominated organic compounds.  相似文献   
43.
This paper describes a rapid method for arsenic (As) speciation by LC-ICP-MS in several types of food samples. Prior to analysis, samples were milled and the As species extracted from biological tissues by sonication in only 2?min with a solution containing MeOH (10%, v/v) plus HNO3 (2%, v/v). As species were separated by LC using an anion exchange column. Method detection limits for AsB, As3+, DMA, MMA and As5+ were 1.3, 0.9, 0.6, 0.7 and 0.8?ng?g?1, respectively. Method accuracy and precision were traceable to Certified Reference Materials SRM1577 bovine liver from the National Institute of Standards and Technology, CE278 mussel tissue from the Institute of Reference Materials and Measurements and DOLT-3 dogfish liver tissue and DORM-3 fish protein from the National Research Council of Canada. Finally, the method was applied to speciate As in food samples (egg, fish muscle, beef and chicken) purchased in Brazilian markets.  相似文献   
44.
45.
常压、真空和脉冲真空渗透脱水加工芒果脯   总被引:4,自引:0,他引:4  
在24℃下,以60%蔗糖水溶液作为渗透溶液,在常压、真空和脉冲真空(压力为510 mmHg)条件下对芒果进行渗透脱水,然后置于热风干燥箱中70℃干燥制成芒果脯,测定芒果脯的硬度、颜色、含水量、复水率.通过感官评定及统计分析得出,真空和脉冲真空渗透脱水制成的芒果脯品质明显优于常压渗透脱水制成的芒果脯.  相似文献   
46.
马勇 《中国酿造》2005,(10):42-43
商丘古称归德,归德白糖蒜是河南商丘传统的土特产品之一,风味独特,深受消费者喜爱。该文介绍了归德白糖蒜的原辅料配比、工艺流程、操作要点、成品质量要求及注意事项等。  相似文献   
47.
以水仙芒为原料,探索芒果果脯加工的新干燥方法,并进一步研究微波-热风联合干燥芒果果脯的工艺条件。分别研究微波功率、转换点含水率以及热风温度3个因素对芒果果脯感官评价的影响,然后采用三因素三水平Box-Behnken设计对芒果果脯的干燥工艺进行优化改良。结果表明,微波与热风联合干燥芒果果脯的最优干燥工艺条件参数为:微波功率395 W、转换点含水率64%、热风温度55℃。  相似文献   
48.
目的测定市场上所售喷码鸡蛋所用喷码油墨的主要成分,为食品安全监管提供数据支撑。方法采用高效液相色谱仪(high performance liquid chromatography,HPLC)、超高效液相色谱-离子阱-飞行时间串联质谱仪(ultra high performance liquid chromatography-ion trap-time of flight tandem mass spectrometry,UPLC-MS-IT-TOF)和气相色谱仪(gas chromatography,GC)对鸡蛋喷码油墨的着色剂和溶剂进行成分分析;采用原子吸收仪(atomic absorption spectrometer,AAS)和原子荧光仪(atomic fluorescence spectrometer,AFS)对油墨中可溶性元素进行定性定量分析。结果市场上所售喷码鸡蛋所用喷码油墨的着色剂大部分为GB2760-2014《食品安全国家标准食品添加剂使用标准》规定中允许使用的"赤藓红"和"亮蓝",溶剂为允许使用的助剂丙酮和乙醇,但个别企业采用的喷码油墨为食品中禁止使用的工业染料"溶剂红49"。当喷码油墨着色剂为食品级"赤藓红"时,生鸡蛋及蒸煮鸡蛋的蛋白和蛋黄里均无喷码用着色剂,蛋壳表面着色剂含量为0.2~2.0 mg/kg,远低于其在食品中允许使用的最大限量值;当喷码油墨着色剂为"溶剂红49"时,鸡蛋的可食用部分均未检出"溶剂红49",但鸡蛋壳、煮鸡蛋的水、与鸡蛋同蒸的馒头中,均检出不同含量的"溶剂红49"。结论市场上所售大多数喷码鸡蛋所用油墨不会给人体健康带来安全风险,但个别企业采用的喷码油墨为食品国家标准禁止使用的工业染料,虽单个鸡蛋表面油墨含量较少,但食用采用这种喷码油墨的鸡蛋可能会危害人体健康,建议相关管理部门加强监管,从源头上避免该现象的发生,保障消费者的食品安全。  相似文献   
49.
Pyrrolizidine alkaloids (PAs) are secondary metabolites of plant families such as Asteraceae or Boraginaceae and are suspected to be genotoxic carcinogens. Recent investigations revealed their frequent occurrence in honey and particularly in tea. To obtain a comprehensive overview of the PA content in animal- and plant-derived food from the European market, and to provide a basis for future risk analysis, a total of 1105 samples were collected in 2014 and 2015. These comprised milk and milk products, eggs, meat and meat products, (herbal) teas, and (herbal) food supplements collected in supermarkets, retail shops, and via the internet. PAs were detected in a large proportion of plant-derived foods: 91% of the (herbal) teas and 60% of the food supplements contained at least one individual PA. All types of (herbal) teas investigated were found to contain PAs, with a mean concentration of 460 µg kg?1 dry tea (corresponding to 6.13 µg L?1 in [herbal] tea infusion). The highest mean concentrations were found in rooibos tea (599 µg kg?1 dry tea, 7.99 µg L?1 tea infusion) and the lowest in camomile tea (274 µg kg?1 dry tea, 3.65 µg L?1 tea infusion). Occurrence of PAs in food supplements was found to be highly variable, but in comparable ranges as for (herbal) tea. The highest concentrations were present in supplements containing plant material from known PA-producing plants. In contrast, only 2% of the animal-derived products, in particular 6% of milk samples and 1% of egg samples, contained PAs. Determined levels in milk were relatively low, ranged between 0.05 and 0.17 µg L?1 and only trace amounts of 0.10–0.12 µg kg?1 were found in eggs. No PAs were detected in the other animal-derived products.  相似文献   
50.
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