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1.
This study examined airborne emissions from cigarette butts for styrene, 2-methyl-2-cyclopenten-1-one, naphthalene, triacetin, and nicotine. Ten experiments were conducted by placing butts in a stainless steel chamber and measuring the chemical concentrations in chamber air. Emission rates were determined from the concentrations. Triacetin and nicotine concentrations were roughly 50% of initial concentrations after 100 hours, while concentrations of other chemicals decayed to less than 10% of initial concentrations within 24 hours. Initial emission rates per cigarette butt ranged from 200 to 3500 ng h−1. Triacetin and nicotine emission rates at 25°C were 1.6 to 2.2 times higher than the rates at 20°C, while the emission rates of other chemicals at 25°C were 1.1 to 1.3 times higher than the rates at 20°C only during the first sampling period. The chemical concentrations and emission rates at 30°C were comparable or lower than the values at 25°C, possibly due to different batches of cigarettes used. The 24-hours emitted mass of nicotine from a cigarette butt at 25°C could be up to 14% of the literature reported nicotine masses emitted from a burning cigarette.  相似文献   
2.
The paper reports a health risk assessment of pesticide exposure among chilli-growing farmers living in Na-Krasaeng Sub-District, Det Udom District, Ubon Ratchathani Province, Thailand. Personal air samples were collected from 46 participants spraying pesticide. These samples were analysed to investigate the farmers’ exposure by inhalation of the organophosphate, chlorpyrifos, which is the predominant pesticide used in the study area. The potential health risk of the farmers through inhalation was estimated by calculating the Hazard Quotient (HQ). The results showed that chlorpyrifos concentrations in inhaled air samples from the farmers ranged from less than the limit of detection, <LOD, to 0.041 mg/m3 with an average of 0.0072 mg/m3. Average daily doses (ADD) of exposure were calculated to be in the range 0–0.007 mg/kg/day with a mean value of 0.0014 mg/kg/day. The estimated risk quotient was 0 to 2.35 and the mean value was 0.84. Accordingly, the chilli-growing farmers were not considered to be a population at risk (mean value of HQ ≤ 1). But, the estimated risk of 17.38% of the study population was higher than the acceptable level (HQ > 1). This indicated that some participants were considered as an individual risk which should be of concern.  相似文献   
3.
We are surrounded by sensory food cues, such as odors, that may trigger (un)conscious decisions and even lead to (over)eating, it is therefore crucial to better understand the effect of food odors on behavioral responses. Food odor exposure has been shown to enhance appetite for food products with similar properties: sensory-specific appetite. This suggests that based on previous encounters with foods, we have learned to detect the nutritional content of foods, through our sense of smell. We investigated the influence of aware exposure of macronutrient-related odors on various measures of eating behavior, in a cross-over intervention study. Thirty two normal-weight healthy and unrestrained Dutch females took part in five test sessions. On each test session, they were exposed to one of five conditions (active smelling of clearly noticeable odors representing food high in carbohydrates, protein, and fat, low in calories, and a no-odor condition for 3-min) and assessed on specific appetite, food preferences and intake. Odor exposure increased congruent appetite after protein-related odor exposure. Similarly, protein-related odor exposure influenced the liking for protein foods and the preference ranking for savory products. However, food intake was not affected by smelling congruent food odors. Together this indicates that exposure to (aware) food odors may mostly influence appetite, but does not impact subsequent food intake. Moreover, appetite seems to be triggered by taste qualities rather than macronutrient information of the food, as signaled by olfactory cues. Future studies should investigate the role of awareness in more detail, to fully understand how odors might be used to steer people towards healthier food choices.  相似文献   
4.
Polychlorinated biphenyl (PCB) contamination of buildings continues to pose an exposure threat, even decades after their application in the form of calks and other building materials. In this research, we investigate the ability of clothing to sorb PCBs from contaminated air and thereby influence exposure. The equilibrium concentration of PCB‐28 and PCB‐52 was quantified for nine used clothing fabrics exposed for 56 days to air in a Danish apartment contaminated with PCBs. Fabric materials included pure materials such as cotton and polyester, or blends of polyester, cotton, viscose/rayon, and/or elastane. Air concentrations were fairly stable over the experimental period, with PCB‐28 ranging from 350 to 430 ng/m3 and PCB‐52 ranging from 460 to 550 ng/m3. Mass accumulated in fabric ranged from below detection limits to 4.5 mg/g of fabric. Cotton or materials containing elastane sorbed more than polyester materials on a mass basis. Mass‐normalized partition coefficients above detection limits ranged from 105.7 to 107.0 L/kg. Clothing acts as a reservoir for PCBs that extends dermal exposure, even when outside or in uncontaminated buildings.  相似文献   
5.
Dampness affects a substantial percentage of homes and is associated with increased risk of respiratory ailments; yet, the effects of dampness on indoor chemistry are largely unknown. We hypothesize that the presence of water‐soluble gases and their aqueous processing alters the chemical composition of indoor air and thereby affects inhalation and dermal exposures in damp homes. Herein, we use the existing literature and new measurements to examine the plausibility of this hypothesis, summarize existing evidence, and identify key knowledge gaps. While measurements of indoor volatile organic compounds (VOCs) are abundant, measurements of water‐soluble organic gases (WSOGs) are not. We found that concentrations of total WSOGs were, on average, 15 times higher inside homes than immediately outside (N = 13). We provide insights into WSOG compounds likely to be present indoors using peer‐reviewed literature and insights from atmospheric chemistry. Finally, we discuss types of aqueous chemistry that may occur on indoor surfaces and speculate how this chemistry could affect indoor exposures. Liquid water quantities, identities of water‐soluble compounds, the dominant chemistry, and fate of aqueous products are poorly understood. These limitations hamper our ability to determine the effects of aqueous indoor chemistry on dermal and inhalation exposures in damp homes.  相似文献   
6.
压水堆核电厂通常采用天然硼进行反应性的化学补偿控制,研究表明采用富集硼替代天然硼,可以优化一回路水化学,降低一回路结构材料腐蚀风险和堆芯沉积风险,降低职业照射剂量。本文分析压水堆核电厂采用富集硼的优势与可行性,介绍国内外核电厂富集硼的应用情况。最后对我国华龙一号堆型和在役压水堆核电厂富集硼的应用提出建议。  相似文献   
7.
目的评估上海市市售韭菜中农药腐霉利的残留情况及居民膳食暴露风险。方法通过2016~2018年间市售韭菜中腐霉利残留的监测数据,结合本市居民食物消费量调查结果,基于蒙特卡罗分析法,采用@Risk7.5软件和风险商值(%ADI)进行风险评估。结果根据GB 2763-2016《食品安全国家标准食品中农药最大残留限量》进行判定,近3年市售韭菜中腐霉利超标率为23.2%,残留量均值和95%分位值(P_(95))分别为0.76 mg/kg和4.81 mg/kg。本市居民通过韭菜腐霉利暴露量均值为6.17×10~(-5) mg·(kg·bw)~(-1)·d~(-1),风险商为0.06%ADI;高端暴露量(P_(95))为1.68×10~(-3)mg·(kg·bw)~(-1)·d~(-1),风险商为1.68%ADI。本市全人群居民通过韭菜、番茄、茄子等8种食用农产品摄入的腐霉利暴露量均值为8.44×10~(-5) mg·(kg·bw)~(-1)·d~(-1)。结论近3年来上海市市售韭菜中腐霉利残留检出率和超标率呈现下降趋势,食品安全监管工作取得一定成效。本市居民通过韭菜摄入腐霉利的风险商值很小,健康风险不大。  相似文献   
8.
Data regarding chewing gum consumption habits and attitudes were collected for 963 children and adolescents (aged 6–14) and 3150 adolescents and adults (aged 13 years+) in the United States (U.S.) using a dedicated online food frequency questionnaire. A total of 79.6% of children/adolescents reported using chewing gum in the last 3 months, whereas 61.8% of adolescents/adults chewed gum in the previous 6 months. The mean and 90th percentile of consumption among children/adolescents aged 6–14 were 1.95 and 4.71 g day?1, equivalent to 0.75 and 1.78 pieces per day, respectively. Stratification by gender and age brackets revealed that the consumption of chewing gum was more heavily reported in boys compared to girls. Among adolescents/adults aged 13 years and older, the mean and 90th percentile of consumption of chewing gum was estimated to be 2.98 and 7.67 g day?1, or 1.05 and 3.00 pieces per day, respectively. Stratification by gender and by age brackets in this cohort did not reveal any marked patterns although it was noted that there was a decrease in the percent consuming with age (from 87.0 to 34.5%). The most commonly reported chew frequency among all ages was ‘two or three times a week’ (23.7 to 26.8%). The average and high-level estimates reported herein provide up-to-date estimates of chewing gum consumption in the U.S. Comparisons of the calculated intake values with those reported from the National Health and Nutrition Examination Survey dataset suggests that national nutrition surveys may result in an under-reporting of the percent consumers, but similar estimates for the daily intakes in g day?1.  相似文献   
9.
Whereas large-scale consumption of energy-dense foods contributes to climate change, we investigated whether exposure to climate change-induced food scarcity affects preferences toward these foods. Humans’ current psychological mechanisms have developed in their ancestral evolutionary past to respond to immediate threats and opportunities. Consequently, these mechanisms may not distinguish between cues to actual food scarcity and cues to food scarcity distant in time and space. Drawing on the insurance hypothesis, which postulates that humans should respond to environmental cues to food scarcity through increased energy consumption, we predicted that exposing participants to climate change-induced food scarcity content increases their preferences toward energy-dense foods, with this effect being particularly pronounced in women. Three experiments—including one preregistered laboratory study—confirm this notion. Our findings jointly demonstrate that receiving information about food shortages distant in time and space can influence current food preferences.  相似文献   
10.
Package design influences consumers’ expectations of a product’s sensory properties and expected healthiness and/or tastiness, and potentially also changes actual product perception during consumption. The robustness of these effects is far from clear, however. This study investigated the influence of package cues signalling either hedonic or healthy product properties on expectations and subsequent product evaluation over repeated consumption.In a between-subjects design, 92 participants evaluated product expectations and taste perceptions of a chocolate-sesame flavoured biscuit with a package emphasizing either its healthy (n = 44) or hedonic (n = 48) aspects, both at a central location (CLT) and during six home use tests (HUT), using both explicit (questionnaires) and implicit (IAT) measures.Package design significantly affected (p < 0.05) consumers’ expectations of the product. They expected the biscuit to be tastier, less attractive and less healthy in the hedonic package condition, and less tasty, more attractive and healthier in the healthy package condition. However, these effects did not transfer to actual product evaluations upon tasting, either blind or tasting in combination with viewing the package during the HUTs. Implicit attitudes did change as a result of repeated exposures, depending on the package consumers were provided with, indicating product-package interactions over time (p < 0.05).In conclusion, package design influences product expectations and associations with its healthiness and attractiveness, which is of relevance in product choice and purchase settings. However, at the stage of (repeated) consumption, intrinsic (sensory) properties become the dominant drivers of products’ sensory and hedonic evaluations, and the impact of package cues seems less potent.  相似文献   
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