The flux growth of some rare-earth and iron group complex oxides

The flux growth of crystals of the following rare-earth complex oxides is reported here for the first time: (Nd, Pb)MnO₃, (Eu, Pb)MnO₃. Tm₂Ge₂O₇ and Pr₂MoO₆. Starting compositions for the flux growth of RBO₃ (R=Nd, Pr, La), (La, Pb)MnO₃, Pb₃Mn₇O₁₅, R₂Ti₂O₇ (R=Tm to Pr), R₂SiO₅ (R=Er, Ho, Dy) and LiCoPO₄ are also given; these compositions have yielded larger crystals than previously reported. In many cases, only a small number of crystals was obtained by spontaneous nucleation.     

Flexural and Split Cylinder Strengths of HSC at Elevated Temperatures

This paper investigates the effect of elevated temperature on the flexural strength (FS) and split cylinder strength (SCS) of high strength concrete (HSC). Four concrete mixes of 50, 90, 110, and 130 MPa grade were prepared and subjected to elevated temperature exposure of 200°C and 400°C, and cooled under slow and quick cooling conditions. In addition, 130 MPa grade concrete specimens were also subjected to 100°C and 600°C exposure temperatures to compare FS and SCS under elevated temperatures. It was observed that with the increase in the elevated temperature, the FS and SCS experienced significant losses. The loss was found to be higher for richer concretes. FS was observed to experience a sharp loss at low temperatures that became gradual later at high temperatures. SCS, however, experienced a gradual loss, though sharper than FS, with the increase in temperature. The results indicated that cooling had a significant effect on the residual values and quick cooling caused greater loss in FS and SCS, than slow cooling at elevated temperatures. The quick cooling was noted to produce maximum loss over slow cooling at temperatures around 400°C.     

Approximation of planar offset curves with globally bounded error for B-spline NC tool paths

The topic of representing the offset of a 2D B-spline curve in the same form has been a topic of research for a long time, and it has many industrial applications, especially in NC tool path generation for pocketing. For B-spline tool paths, it is often required that the tool paths have fewer control points, lower base function degree, and the approximation error is guaranteed within a given tolerance over the entire curve. However, the existing methods utilising global error control approximate the offsets of 2D free-form curves with high function degree and many control points. Although these offsets are useful in computer-aided design, they are inappropriate for the use of CNC machining. To address the problems in order to generate high quality B-spline tool paths, this original work formulates an error function of the offset approximation and then constructs a NURBS curve to globally bound the errors. By checking the maximum coefficient of the bounding curve, the upper bound of all the approximated offset errors is found and the errors can be reduced by segmenting the curve at appropriate knot values. The proposed new approach is more efficient, and the resulting offset approximations are more accurate, with fewer control points and lower function degree. It is useful to generate B-spline tool paths for CNC pocketing, which have the potential for other applications in industry.     

Investigating the state-of-the-art in whole-body MR-based attenuation correction: an intra-individual,inter-system,inventory study on three clinical PET/MR systems

Objective

We assess inter- and intra-subject variability of magnetic resonance (MR)-based attenuation maps (MRμMaps) of human subjects for state-of-the-art positron emission tomography (PET)/MR imaging systems.

Materials and methods

Four healthy male subjects underwent repeated MR imaging with a Siemens Biograph mMR, Philips Ingenuity TF and GE SIGNA PET/MR system using product-specific MR sequences and image processing algorithms for generating MRμMaps. Total lung volumes and mean attenuation values in nine thoracic reference regions were calculated. Linear regression was used for comparing lung volumes on MRμMaps. Intra- and inter-system variability was investigated using a mixed effects model.

Results

Intra-system variability was seen for the lung volume of some subjects, (p = 0.29). Mean attenuation values across subjects were significantly different (p < 0.001) due to different segmentations of the trachea. Differences in the attenuation values caused noticeable intra-individual and inter-system differences that translated into a subsequent bias of the corrected PET activity values, as verified by independent simulations.

Conclusion

Significant differences of MRμMaps generated for the same subjects but different PET/MR systems resulted in differences in attenuation correction factors, particularly in the thorax. These differences currently limit the quantitative use of PET/MR in multi-center imaging studies.

     

Effect of Kiam (Cotylelobium lanceolatum Craib) Wood Extract on the Haemoglobin-Mediated Lipid Oxidation of Washed Asian Sea Bass Mince

Introduction

Effect of ethanolic kiam wood extract (EKWE; 12 0.05% and 0.1%, w/w) on the retardation of haemoglobin-mediated lipid oxidation of washed Asian sea bass mince added without and with menhaden oil stored in ice up to 10 days was investigated.

Results and discussion

Samples containing haemoglobin had the highest peroxide value (PV) within the first 8 days and possessed the greater amount of thiobarbituric acid-reactive substances (TBARS), compared to those added with no haemoglobin (P?<?0.05), regardless of 5% menhaden oil addition. Incorporation of 5% (v/w) menhaden oil to the washed mince had no impact on the formation of PV and TBARS, compared with oil-free samples during the storage (P?>?0.05). With addition of EKWE, lipid oxidation in washed mince added with haemoglobin and menhaden oil was retarded, especially when the higher level (0.1%; w/w) was used, as evidenced by lowered PV and TBARS. Formation of volatile lipid oxidation compounds was retarded in the sample containing oil and haemoglobin and treated with 0.1% EKWE, compared with that without the addition of EKWE after 10 days of storage in ice (P?<?0.05).

Conclusion

Sensory analysis revealed that samples containing haemoglobin without and with oil added had the highest intensity of fishy odour, compared to those treated with EKWE (0.05% and 0.1%) and the control sample (washed mince; P?<?0.05). Thus, EKWE, especially at a level of 0.1%, could serve as a potential natural antioxidant in prevention of lipid oxidation and retardation of development of fishy odour and volatile lipid oxidation compounds in washed mince during iced storage.     

Controlled release of Montelukast Sodium from pH-sensitive injectable hydrogels

pH sensitive hydrogels showed excellent drug release properties, with promise for other biomedical applications. Also, the impact of molecular weight (MW) and degree of deacetylation (DDA) of chitosan on the fabricated chitosan/poly (vinyl alcohol) (3:1 mol ratio) hydrogel with selective silane crosslinker amount was evaluated for controlled drug delivery. The FTIR spectroscopy confirmed the incorporated components and the developed interactions among the polymer chains. The hydrogel characteristics were expressed by their responsive behaviour in different environments (water, ionic media and pH). The hydrogel sample (CH1000) having chitosan with higher MW and DDA exhibited more thermal stability and bacterial growth inhibition against E.coli. All hydrogels exhibited maximum swelling at basic and neutral pH and less swelling was observed in acidic media. For drug release analysis performed in simulated gastric fluid, hydrogel showed controlled drug release in 2 h but it was more than 10%, consequently cannot be used for oral purpose. In simulated intestinal fluid, hydrogels exhibited more than 80% release within 90 min. This characteristic phenomenon at neutral pH empowered hydrogel appropriate towards injectable and targeted controlled release of applicable drug. It was concluded that the prepared hydrogel can be administered directly into the venous circulation through syringe and can be used with better results for biomedical applications.     

Comparison of compression properties of stretchable knitted fabrics and bi-stretch woven fabrics for compression garments

Stretchable fabrics have diverse applications ranging from casual apparel to performance sportswear and compression therapy. Compression therapy is the universally accepted treatment for the management of hypertrophic scarring after severe burns. Mostly stretchable knitted fabrics are used in compression therapy; but in the recent past, some studies have also been found on bi-stretch woven fabrics being used as compression garments as they also have been found quite effective in the treatment of edema. Therefore, the objective of the present study is to compare the compression properties of stretchable knitted and bi-stretch woven fabrics for compression garments. For this purpose, four woven structures and four knitted structures were produced having same areal density and their compression, comfort and mechanical properties were compared before and after 5, 10 and 15 washes. The four knitted structures used were single jersey, single locaste, plain pique and honeycomb, whereas the four woven structures produced were 1/1 plain, 2/1 twill, 3/1 twill and 4/1 twill. The compression properties of the produced samples were tested by using kikuhime pressure sensor and it was found that bi-stretch woven fabrics possessed better compression properties before and after washes and retain their durability after repeated use, whereas knitted stretchable fabrics lost their compression ability after repeated use and the required sub-garment pressure of the knitted structures after 15 washes was almost half that of woven bi-stretch fabrics.     

Utilization of moringa oleifera and nanofiltration membrane to treat palm oil mill effluent (POME)

The palm oil mill effluent imposes environmental issues because of natural and supplement substance. This waste has a significant amount of biological oxygen demand, total suspended solids, chemical oxygen demand, and turbidity. Moringa oleifera seeds′ performance analysis as natural coagulants during the pretreatment stage of palm oil mill effluent before it is filtered through commercial nanofiltration membrane is the focus of the current study. The untreated palm oil mill effluent has 2,410 mg/L biological oxygen demand, 3,900 mg/L chemical oxygen demand, 865 NTU turbidity, 41,900 mg/L total suspended solids, and 4.61 pH. The significant reduction occurred in the feed parameters viz., 91.7 % for biological oxygen demand, 83.0 % for chemical oxygen demand, 67.7 % for total dissolved solids, and 72.8 % for turbidity after the pretreatment; however, the pH increased to 4.88. Design expert® was used to design the experiments and optimize the palm oil mill effluent pretreatment process via a one-factor experimental design. The optimized solution has a 0.994 desirability index. Finally, it was concluded that with ever-tightening environmental standards, moringa oleifera could provide a cheap, green, and potential natural alternative to the existing coagulants employed to treat the palm oil mill effluent.