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排序方式: 共有1333条查询结果,搜索用时 31 毫秒
1.
Food- and waterborne viruses, such as human norovirus, hepatitis A virus, hepatitis E virus, rotaviruses, astroviruses, adenoviruses, and enteroviruses, are major contributors to all foodborne illnesses. Their small size, structure, and ability to clump and attach to inanimate surfaces make viruses challenging to reduce or eliminate, especially in the presence of inorganic or organic soils. Besides traditional wet and dry methods of disinfection using chemicals and heat, emerging physical nonthermal decontamination techniques (irradiation, ultraviolet, pulsed light, high hydrostatic pressure, cold atmospheric plasma, and pulsed electric field), novel virucidal surfaces, and bioactive compounds are examined for their potential to inactivate viruses on the surfaces of foods or food contact surfaces (tools, equipment, hands, etc.). Every disinfection technique is discussed based on its efficiency against viruses, specific advantages and disadvantages, and limitations. Structure, genomic organization, and molecular biology of different virus strains are reviewed, as they are key in determining these techniques effectiveness in controlling all or specific foodborne viruses. Selecting suitable viral decontamination techniques requires that their antiviral mechanism of action and ability to reduce virus infectivity must be taken into consideration. Furthermore, details about critical treatments parameters essential to control foodborne viruses in a food production environment are discussed, as they are also determinative in defining best disinfection and hygiene practices preventing viral infection after consuming a food product.  相似文献   
2.
介绍了紫外线消毒技术在二次供水中的应用情况,并进行了二次供水紫外线消毒实验。结果表明:①紫外线消毒会使二次供水中的余氯略有降低,但是仍满足我国《生活饮用水卫生标准》(GB 5749—2006)的限值要求;②紫外线消毒在80 m J/cm2辐射剂量内仅小幅改变水中部分有机物的官能团;③紫外线消毒对二次供水中消毒副产物(DBPs)的浓度和生成几乎没有影响。  相似文献   
3.
为提高金枪鱼副产物的利用率,减少资源浪费,本试验基于1,2-二氯乙烷体系结合丙酮沉淀法,建立从金枪鱼副产物中同时提取脂质和鱼油的新方法。采用气相色谱法和液相色谱-质谱联用法分别对提取脂质中鱼油和磷脂进行脂质组学研究。通过调节溶剂体系得到1,2-二氯乙烷-甲醇的最佳体积比为1∶2。进一步优化提取条件,得到磷脂和鱼油的得率分别为0.944%和17.306%。利用气相色谱法分析甲酯化的鱼油中的脂肪酸甲酯成分,同时在负离子全扫描模式下利用液相色谱-质谱联用技术对磷脂分子进行分离鉴定和相对定量分析。结果显示:鱼油中主要含有DHA、棕榈酸、油酸、EPA等18种脂肪酸,其中多不饱和脂肪酸占36.678%。从磷脂样品中共检出16种磷脂酰胆碱,14种磷脂酰乙醇胺,11种磷脂酰肌醇和12种磷脂酰丝氨酸,同时,结果显示所有磷脂分子种中包含ω-3多不饱和脂肪酸链的磷脂所占比例较高。研究表明,基于1,2-二氯乙烷的提取方法可提取金枪鱼副产物中的磷脂和鱼油,相比传统方法更安全,更适用于食品加工业。  相似文献   
4.
The conversion of food industry by-products to compounds with high added value is nowadays a significant topic, for social, environmental, and economic reasons. In this paper, calcium phosphate-based materials were obtained from black scabbardfish (Aphanopus carbo) bones and grey triggerfish (Balistes capriscus) skin, which are two of the most abundant fish by-products of Madeira Island. Different calcination temperatures between 400 and 1000°C were employed. Materials obtained from calcination of bones of black scabbard fish were composed by homogeneous mixtures of hydroxyapatite (Ca10(PO4)6(OH)2, HAp) and β-tricalcium phosphate (β-Ca3(PO4)2, β-TCP). Because of the high biocompatibility of HAp and the good resorbability of β-TCP, these natural biphasic materials could be very relevant in the field of biomaterials, as bone grafts. The ratio between HAp and β-TCP in the biphasic compound was dependent on the calcination temperature. Differently, the material obtained from skin of grey triggerfish contained HAp as the main phase, together with small amounts of other mineral phases, such as halite and rhenanite, which are known to enhance osteogenesis when used as bone substitutes. In both cases, the increase of calcination temperature led to an increase in the particles size with a consequent decrease in their specific surface area. These results demonstrate that from the fish by-products of the most consumed fishes in Madeira Island it is possible to obtain bioceramic materials with tunable composition and particle morphology, which could be promising materials for the biomedical field.  相似文献   
5.
针对协同消毒工艺在水厂实际应用中存在的问题和难点,通过对水厂协同消毒工艺的控制进行升级改造及模拟实验,研究了传统控制与智慧控制协同消毒在多种因素影响下的实验结果。相较传统控制,智慧控制协同消毒可将消毒剂控制指标精度提高72%左右、消毒剂投加量减少16%左右、消毒副产物的生成量减少22%左右。在水厂协同消毒应用中智慧控制较传统控制具有更好的控制效果及推广价值。  相似文献   
6.
《Ceramics International》2022,48(9):12660-12674
Zinc oxide is one of the most versatile nanostructured materials with a broad range of applications. Besides, its physicochemical properties can be tuned easily by synthesis conditions to be optimal for a specific application. In our group, we aim for the production of visible light-active materials with enhanced antimicrobial activity. Thus, we synthesize ZnO–Cu2+and Ag@ZnO–Cu2+ by using a fast and robust microwave solvothermal reaction. We investigate the limit of solubility of Cu2+into ZnO lattice producing Cu doped ZnO materials with different doping levels (1, 2, 3, 4, and 5 at. %, Cu/Zn). We also investigate the role of the copper precursor, using copper(II) acetate or copper(II) sulfate as model precursors. Copper acetate incorporates more efficiently into ZnO lattice by decreasing the Eg value of the doped materials at low doping levels. Furthermore, we study the composites Ag@ZnO–Cu2+ aiming to reduce doping levels and to improve antimicrobial activity. Characterization of the materials by different techniques demonstrates their uniform size, purity, crystallinity, and visible light activity. In this study, we evaluate airborne fungal contamination and demonstrate the capacity of ZnO–Cu2+ and Ag@ZnO–Cu2+ to inhibit fungal growth. We studied the microbiological quality of indoor air (vivarium) by sampling air under different conditions. By sampling air with a photocatalytic prototype, the amount of fungi in the air decreases considerably, particularly fungi that can enter the lung. In addition, ZnO–Cu2+ shows excellent antifungal activity against Candida sp at low doses. We use Atomic force microscopy (AFM) and holotomographic microscopy (HTM) to provide further evidence on the capacity of the prepared materials to achieve effective damage to fungal cells and to inhibit biofilm formation.  相似文献   
7.
Campylobacteriosis is one of the most common bacterial infections worldwide causing economic costs. The high prevalence of Campylobacter spp. in poultry meat is a result of several contamination and cross‐contamination sources through the production chain. Moreover, survival mechanisms, such as biofilm formation, viable but nonculturable state, and antimicrobial resistance, enable its persistence during food processing. Therefore, mitigation strategies are necessary in order to avoid and/or inactivate Campylobacter at farm, abattoir, industry, and retail level. In this review, a number of potential strategies and novel technologies that could reduce the prevalence of Campylobacter in poultry meat have been identified and evaluated to provide a useful overview. At farm level for instance, biosecurity, bacteriocins, probiotics, feed and water additives, bacteriophages, and vaccination could potentially reduce colonization in chicken flocks. However, current technologies used in the chicken slaughter and processing industry may be less effective against this foodborne pathogen. Novel technologies and strategies such as cold plasma, ultraviolet light, high‐intensity light pulses, pulsed electric fields, antimicrobials, and modified atmosphere packaging are discussed in this review for reducing Campylobacter contamination. Although these measures have achieved promising results, most have not been integrated within processing operations due to a lack of knowledge or an unwillingness to implement these into existing processing systems. Furthermore, a combination of existing and novel strategies might be required to decrease the prevalence of this pathogen in poultry meat and enhance food safety. Therefore, further research will be essential to assess the effectiveness of all these strategies.  相似文献   
8.
Rhenium disulfide (ReS2) differs fundamentally from other group‐VI transition metal dichalcogenides (TMDs) due to its low structural symmetry, which results in its optical and electrical anisotropy. Although vertical growth is observed in some TMDs under special growth conditions, vertical growth in ReS2 is very different in that it is highly spontaneous and substrate‐independent. In this study, the mechanism that underpins the thermodynamically favorable vertical growth mode of ReS2 is uncovered. It is found that the governing mechanism for ReS2 growth involves two distinct stages. In the first stage, ReS2 grows parallel to the growth substrate, consistent with conventional TMD growth. However, subsequent vertical growth is nucleated at points on the lattice where Re atoms are “pinched” together. At such sites, an additional Re atom binds with the cluster of pinched Re atoms, leaving an under‐coordinated S atom protruding out of the ReS2 plane. This under‐coordinated S is “reactive” and binds to free Re and S atoms, initiating growth in a direction perpendicular to the ReS2 surface. The utility of such vertical ReS2 arrays in applications where high surface‐to‐volume ratio and electric‐field enhancement are essential, such as surface enhanced Raman spectroscopy, field emission, and solar‐based disinfection of bacteria, is demonstrated.  相似文献   
9.
10.
通过优化二氧化氯结合加热法处理新鲜鸡蛋提高其杀菌效率,缩短其消毒时间,并对蛋液的理化及功能性质进行分析。结果表明,最佳蛋源前处理方法为浓度为125 mg/L的二氧化氯溶液浸泡5 min后,65℃热水冲洗120 s,对蛋壳表面的微生物的杀菌率达到99.9%。前处理方法对蛋液起泡性、泡沫稳定性、挥发性盐基氮没有显著影响;经前处理后的蛋液储存8周后,菌落总数、起泡性和挥发性盐基氮均明显优于对照组。该方法可以有效延长液蛋制品的保质期。  相似文献   
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