Improving the flame retardancy of polypropylene foam with piperazine pyrophosphate via multilayering coextrusion of film/foam composites

A series of 16-layer polypropylene/flame retardant (PP/FR) film/foam composite structures were produced by microlayer coextrusion. A highly branched PP was used in the foam layers to increase strain hardening and cell stability, while the PP used in the film layers was a high shear viscosity grade to confine bubble growth. In addition to improved tensile properties, the PP/FR composite film/foams exhibited five times the compression modulus of PP/FR composite foams at each FR loading level. The thermal stabilities of the composites were investigated, exhibiting three step decompositions. The FR particles were effective in decreasing flammability by forming intumescent char. The PP/FR-film/foam-20 showed self-extinguishing behavior in a modified vertical burn test, while the PP/FR-foam-20 sample continued to burn. Cone calorimetry demonstrated that PP/FR film/foams had lower heat release than PP/FR foams due to the unique alternating film/foam structure of PP/FR film/foams. Scanning electron microscopy imaging of the residual chars from fire testing that the PP/FR composite film/foams showed a more continuous protective char surface when compared with PP/FR composite foams at each FR concentration. The combined data indicate that the formation of a surface film on top of a foam ensures a robust intumescent fire protective barrier for partly foamed materials and shows a new way toward lightweight materials with improved fire safety performance. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48552.     

反渗透/电去离子：食品和饮料实验室首选净水技术

目前,人们对食品饮料的分析检验的要求越来越严格.随着分析灵敏度的提高,人们对食品饮料分析中用水的质量提出了更高的要求.许多实验室仍然采用蒸馏的方法来生产纯水,但是采用能够提供更高水质的反渗透和电去离子系统更经济.     

Quantifying the extent of space shortages: English dwellings

Lack of internal space is a problem in UK homes, and is often linked to a lack of space standards for housing in the UK. Although previous studies have examined new-build housing, this paper uses a new method to study 16 000 dwellings in the English Housing Survey (EHS) 2010 to examine existing housing and compare them with a modern space standard in an attempt to quantify the extent and magnitude of the problem. Dwellings in the survey were compared against a slightly modified version of the London Housing Design Guide 2010 internal space standard. It was found that between 21% and 55% of dwellings failed to meet the standard; and that flats and small terraced houses were most commonly below the standard. Dwellings were also frequently found to be under-occupied in comparison with the number of bedrooms. This research hypothesized that this was a result of the lack of space. To illustrate the use of this new analysis method, a recent change to the Housing Benefit system (colloquially known as the ‘Bedroom Tax’) has been considered. Households receiving Housing Benefit were more likely to be undersized, suggesting that the policy to withdraw housing benefits from these households may be misguided.     

An Experimental Study on the Additional Settlement of Footings Resting on Granular Soils by Water Table Rise

When the water table rises in a granular soil mass, a large additional settlement of footing resting on such a soil mass is commonly expected. Laboratory model tests show that when the water table rises to the footing level, there can be an additional 400 to 500% of the settlements compared to when the soil is dry. To understand the mechanics of the additional settlements of footings resting on the granular soil masses caused by water table rise, an investigation into the change in the Young's modulus of soil was therefore made using oedometer tests. A relation between the saturated and the dry Young's moduli of the granular soils is presented for use in the elastic analysis of footing settlements. The findings of the investigation were then used to predict the additional settlements of a model footing when subjected to a water table rise, using elastic analysis. The theoretical predictions of the additional settlements are lower than the actual additional settlements observed in the settlement tests conducted in the laboratory using model tests. The model tests show that the additional settlements are larger in loose sands than in dense sands.     

Metabolic profile biomarkers of metal contamination in a sentinel terrestrial species are applicable across multiple sites

In this study, we addressed the question of whether an omic approach could genuinely be useful for biomarker profile analysis across different field sites with different physicochemical characteristics. We collected earthworms (Lumbricus rubellus) from seven sites with very different levels of metal contamination and prevailing soil type and analyzed tissue extracts by 1H nuclear magnetic resonance spectroscopy. Pattern recognition analysis of the data showed that both site- and contaminant-specific effects on the metabolic profiles could be discerned. Zinc was identified as the probable major contaminant causing a metabolic change in the earthworms. Individual sites could be resolved on the basis of NMR spectral profiles by principal component analysis; these site differences may also have been caused by additional abiotic factors such as soil pH. Despite an inevitable degree of confounding between site and contaminant concentrations, it was possible to identify metabolites which were correlated with zinc across all different sites. This study therefore acts as a proof of principle for the use of NMR-based metabolic profiling as a diagnostic tool for ecotoxicological research in polluted field soils.     

Interrelationships of breed type, USDA quality grade, cooking method, and degree of doneness on consumer evaluations of beef in Dallas and San Antonio, Texas, USA

The objective of this research was to evaluate the consumer controlled factors of cooking method and degree of doneness on top loin steaks from different USDA quality grades (Low Choice, High Select or Low Select) and breed-types (English, Continental European Cross or Brahman Cross). In addition, cities within the same region were evaluated for differences in consumer controlled factors and palatability responses. The in-home product test was conducted in Dallas and San Antonio, Texas, USA. Consumers (n=173) evaluated steaks for overall like (OSAT), tenderness (TEND), juiciness (JUIC), and flavor (FLAV) using 23-point hedonic scales. Respondents in Dallas cooked their steaks to higher degrees of doneness than did those in San Antonio. Outdoor grilling was the most frequently used method of cookery for steaks in both cities. Generally, consumers in San Antonio gave higher palatability ratings to Choice steaks and Dallas consumers gave higher ratings to Select steaks. The interactions of city×cooking method, breed-type×cooking method, and degree of doneness×cooking method were significant for all palatability attributes. In addition, the interaction of cooking method×quality grade was significant for TEND, JUIC, and FLAV. Warner-Bratzler shear (WBS) force was determined on a steak from each strip loin. Steaks from Continental European Cross cattle and Low Choice carcasses had the lowest WBS values. Differences in consumer preparation of beef top loin steaks present very unique challenges for the beef industry. Consumer information programs may serve a valuable role in connecting consumer perceptions with the preparation techniques needed to consistently achieve satisfaction.     

An Open Grid Services Architecture Primer

To expand the use of distributed computer infrastructures as well as facilitate grid interoperability, OGSA has developed standards and specifications that address a range of scenarios, including high-throughput computing, federated data management, and service mobility.     

Drying kinetics,physico‐chemical properties,antioxidant activity and phenolic composition of foam‐mat dried germinated rice bean (Vigna umbellata) hydrolysate

This research was aimed to study physico‐chemical properties and antioxidant activities of foam‐mat dried germinated rice bean (Vigna umbellata) hydrolysate. Germination led to an increase in released phenolic content and antioxidant activity (DPPH radical scavenging activity and FRAP) of rice bean hydrolysate. The hydrolysate obtained from germinated rice bean (GRB) and non‐germinated rice beans (NGRBs) was foam‐mat dried at 60 and 70 °C. Semi‐theoretical and empirical model could suitably describe the drying characteristic of foamed bean hydrolysate. Total phenolic content and antioxidant activities of foam‐mat dried samples decreased with increasing air‐drying temperature (P ≤ 0.05). Gallic acid, catechol and epicatechin were major phenolic compounds in foam‐mat dried samples prepared from both GRB and NGRB. The higher phenolic content and antioxidant activities were found in foam‐mat dried hydrolysate of GRB. Electron spin resonance spectrometry revealed that foam‐mat dried rice bean hydrolysate showed a strong ability to scavenge free radicals, especially carbon‐centred radicals.