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Bisphenol A (BPA) is used as an additive in polyvinyl chloride (PVC) products, including stretch films used for food packaging. The BPA contents were investigated of several brands of stretch film bought locally but marketed internationally or throughout Spain and which were presumably produced at different manufacturing plants. Their major components were identified by FTIR (Fourier Transform Infrared Spectrometry) and horizontal attenuated total reflectance, and the migration of BPA from these materials into the standard European Union food simulants was determined by high-performance liquid chromatography (HPLC) using both fluorescence (FL) and ultraviolet (UV) detection, the identity of the analyte being confirmed by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS). The two HPLC detection methods had different detection limits (30 μg l-1 for UV, 3 μg l-1 for FL), but afforded virtually identical BPA determinations for the samples tested. BPA contents ranging from 40 to 100 mg kg-1 were found in three of the five PVC-based films analysed, and a content of 500 mg kg-1 was found in a fourth; for these determinations, extraction into acetonitrile was used. In standard tests of migration into water, 3% acetic acid and olive oil over 10 days at 40°C, migration from a given film was in all cases greatest into olive oil. Migration from the films with non-zero BPA contents ranged from 3 to 31 μg dm-2, values higher than those reported for many other food-contact materials, but lower than the European Union specific migration limit for BPA. PVC stretch film nevertheless may make a significant contribution to contamination of foodstuffs by BPA, and should be taken into account in estimating BPA intake or exposure to this substance.  相似文献   
3.
The capacity of the natural antioxidant to retard oxidation of polyunsaturated fatty acids in hake (Merluccius merluccius) muscle was investigated. Hake fillets were packaged in low‐density polyethylene with the natural antioxidant (sample C1 = 7 mg/dm2 film and sample C2 = 24 mg/dm2 film) or without the antioxidant (control sample) and frozen for 12 months at ?20°C. The results confirm the efficacy of an active packaging with a natural antioxidant derived from barley husks to slow the progress of lipid hydrolysis and increase oxidative stability in hake muscle. Determination of peroxide value, conjugated dienes, free fatty acids, thiobarbituric acid reactive substances (TBARS) and anisidine value (AV) proved suitable for studying lipid hydrolysis and primary and secondary lipid oxidation over time. After 6 months of frozen storage, the TBARS levels were lower in hake packed with low‐density polyethylene with the natural antioxidant (C1 and C2) than in the control sample; at month 12, the TBARS values of C1 and C2 were lower (16 and 21%, respectively) than the control samples. AVs observed in samples C1 and C2 at month 9 were lower than those observed in the control sample at month 12. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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The main results of the bloodstream infection (BSI) component of the Belgian National Programme for the Surveillance of Hospital Infections (NSIH project) are reported. From October 1992 to September 1996, 117 hospitals (59.1% of Belgian acute-care institutions) reported 13678 nosocomial BSIs. The incidence was 7.05 BSI episodes per 10000 patient-days. The incidence of BSI increased with hospital size and over time. Bloodstream infections were secondary to an infectious body site in 40.3% of the episodes, catheter-related in 23.5%, and of unknown origin in 36.2%. The associated in-hospital mortality was 31.4% and was highest in BSIs secondary to a respiratory tract infection (49.3%). In intensive care units, the incidence of BSI was 38.5 per 10000 patient-days. Coagulase-negative staphylococci were the most prevalent microorganisms (22%), followed by Staphylococcus aureus (14.1%) and Escherichia coli (13.5%). In catheter-related BSIs, these proportions were 41.9%, 18.8%, and 2.3%, respectively. The proportion of polymicrobial episodes was 9.9%. Methicillin resistance in Staphylococcus aureus was 22.3%. With its high participation rate, the NSIH project has characterized the epidemiology of nosocomial BSIs in Belgium during the period studied.  相似文献   
6.
The key block for the production of polycarbonate (PC) is bisphenol A (BPA). Recent studies have proven that this monomer is able to migrate from PC baby bottles into food simulants and, although this is a polemical subject, numerous investigations indicate that BPA may have an effect on the human health. For these reasons, BPA safety regarding human exposure has recently become an alarming issue.Amines are a class of chemicals which are present in foodstuffs, such as milk. For this reason PC baby bottles, while being used, are continuously in contact with several amines, some of which are able to cause PC aminolysis, resulting in the release of BPA.In this work, 16 substances (14 with amine groups and 2 with amide groups) were tested in order to verify if they were able to increase BPA release by increasing PC depolymerization. High-performance liquid chromatography (HPLC) with fluorescence detection (FLD) and gas chromatography coupled to mass spectrometry (GC–MS) were used to quantify and identify the BPA, respectively. Although most of the substances tested did not increase the release of BPA from PC, some of them had a significant effect and high levels of this monomer were measured in the solutions. Of all of the amines tested that originating the worst case of BPA release was 1,4-diaminobutane. Also known as putrescine, 1,4-diaminobutane is a biogenic amine that results from protein degradation and it may be present in milk. In this case, BPA concentration in the solution was more than 5000 times the level found in the control sample.  相似文献   
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Editorial     

Editorial Introduction

Editorial  相似文献   
8.
受控倒塌芯片连接新工艺是一种由IBM公司开发、由Suss Micro Tec公司推向商品化的新型焊凸形成技术。受控倒塌芯片连接新工艺采用各种无铅焊料合金致力于解决现有的凸台。形成技术限定,使低成本小节距焊凸形成成为可能。受控倒塌芯片连接新工艺是一种焊球转移技术,熔焊料被注入预先制成并可重复使用的玻璃模板(模具)。这种注满焊料的模具在焊料转入圆片之前先经过检查以确保高成品率。注满焊料的模具与圆片达到精确的接近后以与液态熔剂复杂性无关的简单工序转移在整个300mm(或300mm以下)圆片上。受控倒塌芯片连接新工艺技术能够在焊膏印刷中实现小节距凸台形成的同时提供相同合金选择的适应性。这种简单的受控倒塌芯片连接新工艺使低成本、高成品率以及快速封装周期的解决方法对于细节距FCiP以及WLCSP凸台形成均能适用。  相似文献   
9.
The aim is to develop active packaging films containing natural antioxidants and to evaluate their capacity to enhance the oxidative stability of beef during refrigeration. The antioxidant activity of a natural extract obtained from a brewery residual waste was evaluated and compared with that of a commercial rosemary extract and two synthetic antioxidants (BHT and propyl gallate). Different concentrations of each antioxidant were also added directly to beef samples, resulting in a reduction in lipid oxidation of up to 70–80% relative to the control. Active antioxidant films coated with PVPP-WS extract reduced lipid oxidation by up to 80%, relative to the control, during cold storage. The use of active packaging films containing natural extracts could improve the oxidative stability of meat products and should therefore be of great interest in the food industry.  相似文献   
10.
A packaging system combining a polyphenol-rich film and vacuum (PPRF–VP) was applied to farmed coho salmon (Oncorhynchus kisutch) muscle for an 18-month storage (−18 °C). For it, two different concentrations of polyphenol compounds (namely, p-coumaric and ferulic acids) obtained from a barley husk extract were applied (PPRF–VP conditions) and compared to vacuum packaging without polyphenol presence (vacuum control; VP condition) and to packaging in the absence of vacuum and polyphenols (control; CP condition). The study was addressed to lipid hydrolysis and oxidation development and to lipid changes related to nutritional value. Both PPRF–VP conditions provided an inhibitory effect (p < 0.05) on conjugated diene and fluorescent compound formation in frozen salmon. Compared to CP condition, vacuum packaging (PPRF–VP and VP conditions) led to lower (p < 0.05) peroxide and anisidine values and to an inhibitory effect (p < 0.05) on α- and γ-tocopherol losses. No effect (p > 0.05) of polyphenol presence and vacuum packaging could be inferred on free fatty acid formation (hydrolysis development) and on polyunsaturated fatty acid retention (polyene index assessment). A low rancid odour development was observed in all kinds of fish samples, this being lower (p < 0.05) in fish kept under vacuum (PPRF–VP and VP) conditions.  相似文献   
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