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41.
刘冬虹  胡晓露  谢永萍  谢文缄  戴航  贾芳  廖惠媚 《当代化工》2017,(12):2451-2453,2586
总结了婴儿纸尿裤(片/垫)和隔尿垫巾的相关标准,通过不同方法方式对婴儿纸尿裤(片/垫)和隔尿垫巾中荧光增白剂进行研究,结果发现有部分婴儿纸尿裤(片/垫)和隔尿垫巾有荧光现象;隔尿垫巾通过擦拭和尿液浸泡时发现荧光迁移的现象;并且检出FWA393(4,4’-双(苯并噁唑-2-基)二苯乙烯)和FWA1842,2’-(2,5-二苯基硫代)双[5-(1,1-二甲基乙基)苯并噁唑])两种荧光增白剂,且大部分的检出值较高。婴幼儿纸尿裤/片、隔尿垫巾等产品其使用对象为免疫系统未发育完善、皮肤较为薄弱且社会关注度极高的婴幼儿,且使用部位非常敏感,该类产品中荧光增白剂含量如此之高应引起有关部门的关注。  相似文献   
42.
Docosahexaenoic acid (DHA)-rich diacylglycerol (DAG)-rich oil was prepared by lipase-catalyzed glycerolysis of microbial oil from Schizochytrium sp. in a solvent-free system. The reaction parameters including lipase type, substrate molar ratio, temperature, lipase concentration, and reaction time were screened. The selected conditions were determined as follows: Novozym® 435 (Novozymes A/S, Bagsvaerd, Denmark) as biocatalyst at 8 wt%, substrate ratio (DHA-rich microbial TAG/glycerol) of 1:1 mol/mol, temperature of 50 °C, and reaction time of 12 hours. Under these conditions, the triacylglycerol (TAG), DAG, and monoacylglycerol (MAG) contents in the product were 36.4%, 48.2%, and 15.4%, respectively. The lipase was reused successively for 18 cycles without significant loss of activity under the conditions given above. Fatty acid composition analysis of the final product showed that the contents of DHA in TAG, DAG, and MAG were 53.9%, 44.9%, and 34.8%, respectively. DHA-rich DAG has the potential to be used as an ingredient in infant formula to increase the bioavailability of DHA.  相似文献   
43.
王俭 《陶瓷研究》2020,(1):108-110
婴戏纹饰即描绘儿童游戏时的画作,是中国人物画的一种,更是陶瓷装饰中常见的传统题材。其主要以儿童为主要绘画对象,表现儿童纯真,或借以其他物象,组成吉祥图案,在我国陶瓷绘画上广泛运用,有着深刻的社会形态特征和思想文化的背景。其始于唐代,兴盛于宋金,明清两朝日臻成熟,并延续至今。在西方艺术史当中,儿童形象大都通过神话人物或宗教相关的艺术品走进人们视野,用以表现某些宗教思想或精神诉求。本文主要探讨陶瓷婴戏纹饰在我国历史发展历程中的演变概况,以及笔者对我国陶瓷婴戏纹饰和西方艺术品中儿童形象横向对比下的一些思考。  相似文献   
44.
Since the safety issue of lysinoalanine (LAL) still remains unresolved, its concentration in infant formulae should be reduced to a minimum. Data collected in the 1980s indicated that LAL is formed in higher amounts in liquid than in powdered formulae. Recently the market of liquid infant formulae is increasing rapidly and there are no new data, so 23 commercial powdered or liquid samples were investigated. In powdered samples, LAL was below the detection limit, whereas liquid adapted formulae contained up to 86 μg/g protein, liquid follow-on formulae up to 390 μg/g protein, and liquid growing milks up to 514 μg/g protein. The concentration of LAL in liquid formulae is considerably lower than in the past; however, the level in a few products remains rather high, especially compared with normal UHT-treated milk. Great differences were observed among products of different companies, which suggests that labelling with the thermal treatment applied would be very advisable. The investigation of some beicost products indicates that LAL is present only in products certainly containing milk proteins. Considering the rather low levels in comparison with liquid infant formulae, the contribution of beicost products to the total LAL daily intake does not seem to be particularly relevant.  相似文献   
45.
国内外婴幼儿配方食品管理体系研究   总被引:1,自引:0,他引:1  
为分析比较国际婴幼儿配方食品法规管理体系,作为我国相关标准制定的参考。收集了食品法典(CODEX)、美国、欧盟和澳新婴幼儿配方食品相关管理法规,包括定义,法规体系和具体规定,进行纵向与横向的比较分析。不同国家或国际组织对于婴幼儿配方食品管理的法规体系各不相同,但对包括特殊医学用途婴儿配方食品的定义,营养成分限量,可添加物质以及安全性指标的规定基本一致,而且强调生产过程的监控和管理。我国在制修订婴幼儿配方食品标准时应充分考虑不同法规标准的协调一致性,尤其对于不同政府部门颁布的法规,以及生产过程管理,确保产品质量与安全。对于国内标准未涉及但在国外有较长安全使用历史的产品,例如各种特殊医学用途婴儿配方食品,应考虑增设标准或通过专门审批和管理渠道进口,确保为具有医学状况的婴儿提供合理膳食促进健康生长,满足我国市场需求。  相似文献   
46.
Public health professionals assert that parents could prevent a substantial portion of infant mortality due to unintentional injury (IMUI) by creating a safe environment for the infant. Examples of safe parenting behaviors include attending to a bathing infant, properly securing a child safety seat in a motor vehicle, and removing soft pillows from a crib. The contraction of regional economies, an ambient phenomenon previously reported to affect salutary behaviors, may distract parents from these routine infant monitoring tasks. I test this distraction hypothesis that the monthly incidence of IMUI will vary inversely with the performance of the economy. I retrieve economic data from the Bureau of Labor Statistics and use data from the Birth Cohort File on 2 618 752 infants in all 26 metropolitan areas of California. Results support the hypothesis in that a 1% decline in employed persons coincides with an 8% increase of IMUI in that month. Findings remain robust to control for individual covariates that could confound observed associations. I discuss my findings in relation to the literature concerned with parental distraction, describe other mechanisms through which the economy may affect IMUI, and recommend further investigation.  相似文献   
47.
Iron solubility, dialysability and transport and uptake (retention + transport) by Caco-2 cells as indicators of iron availability have been estimated in the in vitro gastrointestinal digests of infant foods (adapted, follow-up and toddler milk-based formulas and fruit juices containing milk and cereals (FMC)). Low correlation coefficients (in all cases R-squared ? 37.1%) were obtained between iron solubility or dialysability versus transport or uptake efficiency – a fact emphasizing the importance of incorporating Caco-2 cell cultures to in vitro systems in order to adapt the conditions to those found in in vivo assays. The highest uptake efficiency corresponded to FMC (25.6–26.1%) and toddler formulas (32.1–41.9%), the samples with the highest ascorbic acid contents and ascorbic acid/iron molar ratios. In addition, the toddler formulas contained caseinphosphopeptides with the cluster sequence SpSpSpEE, representing the binding site for minerals. In adapted formulas, greater iron uptake efficiency was obtained for the formulation containing ferrous lactate (22.7%) versus ferrous sulfate (4.7%).  相似文献   
48.
Francisella tularensis is a Gram-negative bacterium that can cause gastrointestinal or oropharyngeal tularemia in humans from ingestion of contaminated food or water. Despite the potential for accidental or intentional contamination of foods with F. tularensis, there are few studies on the long-term survivability of this organism in food matrices. Infant formula has previously been implicated as a vehicle for the transmission of a variety of bacterial pathogens in infants. In this study, we investigated the survival of F. tularensis in dehydrated infant formula under various storage conditions. F. tularensis was stored for up to 12 weeks in dehydrated infant formula in an ambient air, dry or nitrogen atmosphere. Viable counts of fresh F. tularensis at 12 weeks in infant formula revealed a 4.15, 3.37 and 3.72-log decrease in ambient air, dry and nitrogen atmosphere, respectively. D-values were calculated (in weeks) as 3.99, 4.68 and 4.47 in air, dry and nitrogen atmosphere, respectively.  相似文献   
49.
Sphingolipids are a group of lipids present in all eukaryotic cells. They consist of a long-chain sphingoid base that is amide-bound to a fatty acid and a polar group on C-1 sphingosine. Sphingosine is the most widespread base in mammals. The goal of this study is to determine the concentrations of free and total sphingosine and sphinganine in infant formulas and human milk. Following the extraction of sphingolipids, base and acidic hydrolysis was preformed. Sphinganine and sphingosine were determined by means of high-performance liquid chromatography. The results of this research illustrate the differences between the concentrations of sphingoid bases in infant formulas and human milk. On the basis of the obtained results, it can be concluded that despite all efforts made to produce infant formulas as similar to human milk as possible, in terms of their structure and the amount of their constituents, there are differences that could be biologically significant and thus need to be further researched.  相似文献   
50.
The presence of Enterobacter sakazakii and other Enterobacteriaceae was surveyed in 82 powdered infant formula milk (IFM) and 404 other food products. The presence of Ent. sakazakii was detected using the conventional method (growth on violet red bile glucose agar plus yellow pigment production on TSA) and a new chromogenic medium (Druggan–Forsythe–Iversen agar, DFI) which enables results to be obtained 2 days earlier than the conventional method. Ent. sakazakii was isolated from 2/82 powdered IFM, 5/49 dried infant foods, 3/72 milk powder, 2/62 cheese products and various dry food ingredients, especially herbs and spices (40/122). Ent. sakazakii was isolated from 67 samples using the DFI medium, however only 19 of the samples were positive following the conventional method. The largest difference in isolation between the two methods was with dry food ingredients.Although Enterobacteriaceae were enumerated from one powdered IFM sample (Klebsiella ozaenae, 200 cfu/g), 7/82 had detectable Enterobacteriaceae after enrichment in EE broth. Using the ISO 6579 2002 method and immuno-magnetic separation technique no Salmonella serovars were isolated from powdered IFM, dried infant foods or milk samples. Therefore hygienic production of powdered IFM and milk production as monitored by control of Salmonella and enumeration of Enterobacteriaceae did not control Ent. sakazakii.  相似文献   
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