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21.
提出了一种基于移动平台的食品分拣机械手,给出其设计指标、机械以及控制系统结构,对其工作空间进行了仿真计算,并对该机械手的末端定位精度进行了实验研究,结果表明基于移动平台的食品分拣机械手设计合理,可以有效地完成精确操作。 相似文献
22.
采用电感耦合等离子发射光谱仪(ICP-AES)对食品中铝含量测定方法的研究。样品经全自动微波消解仪(硝酸+过氧化氢)进行预处理,消解液用ICP-AES进行检测。结果表明,采用ICP-AES对食品中铝的测定方法具有灵敏度高、检测限低、高效、稳定的优点。此方法检出限为2μg/L,相对标准偏差低于1%,在0~10.0 mg/L 范围内,线性良好(R=0.9997),回收率为92.8%~99.6%。测定结果满意。 相似文献
23.
作者通过分析现行白酒行业标准体系构成,从原辅材料、酿造、勾调、包装及检测等环节剖析了白酒行业的食品安全管理现状,提出了深刻的思考。 相似文献
24.
Foodborne illnesses are syndromes including nausea, vomiting, abdominal cramps and diarrhea caused by the ingestion of food contaminated by chemical substances or microorganisms and/or their toxins. Reporting of food poisoning has been mandatory for European Union member states since 2003. Data collected by the European Food Safety Authority (EFSA) include number of outbreaks per causative agent, number of human cases as well as hospitalization and death rates. This paper will focus on meat products as food vehicles for FBOs. Following the legal definition of meat and meat products and the European reporting scheme, the main pathogenic bacteria will be presented. 相似文献
25.
介绍了灰色预测理论的基本原理、建立灰色预测模型GM(1,1)的过程及求解方法,并将此种方法应用到企业易腐食品需求预测中,取得了较好的预测效果,为企业减少产品损耗,提高盈利提供了有力支撑。 相似文献
26.
添加剂及储藏温度对糯性粉团抗老化的研究 总被引:1,自引:0,他引:1
研究了在不同储藏温度(-18、4、25和37℃)下的糯性粉团,通过分析储藏0-5 d中的水分含量、水分活度、质构特性和热力学特性的变化来研究老化性质,并对食品添加剂对其抗老化作用作了研究。研究表明:(1)在各个储藏温度条件下,食品添加剂的加入可以有效地抑制糯性粉团的老化回生,可使糯性粉团的硬度较小、水分含量较高、水分活度较低、DSC测定的ΔH较小。(2)在-18℃条件下储藏的糯性粉团的老化速率最慢,经过自然解冻后其品质接近于新鲜糯性粉团。当储藏温度位于冰点温度(0℃)以上时,在4℃储藏的糯性粉团的老化速率相比25℃和37℃要快很多,且37℃条件下储藏的糯性粉团的老化速率低于在25℃条件下储藏的糯性粉团。表明糯性粉团最适宜的储藏温度应是-18℃。而当储藏温度位于冰点温度(0℃)以上时,温度越低,糯性粉团的老化回生愈加显著。 相似文献
27.
28.
《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(4):723-733
Due to the 2011 labelling of styrene monomer as “reasonably anticipated to be a human carcinogen” by the National Institutes of Health’s National Toxicology Program (NTP) and the controversy over whether styrene oligomers mimic the physiological effects of estrogen, an updated review of styrene monomer and oligomers in food and food contact materials (FCMs) was performed. The concentrations of styrene monomer and oligomers were determined in 24 polystyrene (PS) products and ranged from 9.3 to 3100 mg kg–1 for the styrene monomer, 130–2900 mg kg–1 for the sum of three styrene dimers, and 220–16,000 mg kg–1 for the sum of six styrene trimers. Foods in contact with PS packaging had styrene monomer concentrations ranging from 2.6 to 163 ng g–1; dimer concentrations from the limit of quantitation (LOQ) to 4.8 ng g–1 and trimer concentrations were all below the LOQ (2 ng g–1). Diffusion coefficients (Dp) and partition coefficients (K) were also calculated for styrene dimers and trimers. The results presented here indicate that styrene monomer concentrations in foods have not significantly changed since the 1980s and monomer concentrations in food packaging quantified in this study were all below USFDA limits. Although styrene dimers and trimers are present in higher concentrations in PS FCMs than the monomer, their migration to food is limited because of their high K values (4 × 102 to 2 × 106) and their low diffusion coefficients in PS products. Additionally, diffusion coefficients calculated using USFDA-recommended food simulants and Arrhenius plots describing the temperature dependence of styrene dimers and trimers can be used in future calculations of dietary intake of the styrene oligomers. 相似文献
29.
《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(9):1584-1595
ABSTRACTPolybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants whose use has contaminated foods and caused subsequent human exposures. To address the issue of possible human exposure, samples from a 2012–13 US meat and poultry (beef, pork, chicken, turkey) study were analysed for seven PBDEs. The mean summed concentrations of the seven BDE congeners (ΣPBDE) from beef, pork, chicken and turkey were 0.40, 0.36, 0.19, and 0.76 ng g–1 lipid weight (lw). The range of ΣPBDEs for all meat classes was 0.01–15.78 ng g–1 lw. A comparison of this study with a 2007–08 study revealed a decline in the median ΣPBDEs for all four meat classes, a reduction of 25.9% to 70.0%, with pork, chicken and turkey PBDE residues being statistically lower relative to the 2007–08 study. BDEs 47 and 99 contributed the most to the ΣPBDE concentrations, indicating likely animal exposures to the penta-BDE formulation. Based on the reported data an estimate of US consumer daily intake of PBDEs from meat and poultry was 6.42 ng day–1. 相似文献
30.